Antinociceptive, anti-inflammatory and antipyretic properties of Melastoma malabathricum leaves aqueous extract in experimental animals.

PubMed

Zakaria, Z A; Raden Mohd Nor, R N S; Hanan Kumar, G; Abdul Ghani, Z D F; Sulaiman, M R; Rathna Devi, G; Mat Jais, A M; Somchit, M N; Fatimah, C A

2006-12-01

The present study was carried out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of the aqueous extract of Melastoma malabathricum leaves in experimental animals. The antinociceptive activity was measured using abdominal constriction, hot-plate, and formalin tests, whereas the anti-inflammatory and antipyretic activities were measured using carrageenan-induced paw edema and brewer's yeast-induced pyrexia tests, respectively. The extract, which was obtained after soaking the air-dried leaves in distilled water for 72 h and then preparing in concentrations of 10%, 50%, and 100% (v/v), was administered subcutaneously 30 min prior to subjection to the above mentioned assays. At all concentrations tested, the extract was found to exhibit significant (P < 0.05) antinociceptive, anti-inflammatory, and antipyretic activities in a concentration-independent manner. Our findings that the aqueous extract of M. malabathricum possesses antinociceptive, anti-inflammatory, and antipyretic activities supports previous claims on its traditional uses to treat various ailments.

Evaluation of antinociceptive effect of Petiveria alliacea (Guiné) in animals.

PubMed

de Lima, T C; Morato, G S; Takahashi, R N

1991-01-01

Petiveria alliacea (Phytolaccaceae) is a bush widely distributed in South America including Brazil, where it is popularly known as "guiné", "pipi", "tipi" or "erva-de-tipi". Brazilian folk medicine attributes to the hot water infusion of its roots or leaves the following pharmacological properties: antipyretic, antispasmodic, abortifacient, antirrheumatic, diuretic, analgesic and sedative. The present study has evaluated the alleged effects of P. alliacea on central nervous system (CNS), particularly, the sedative and analgesic properties of root crude aqueous extract of this plant in mice and rats. This extract showed an antinociceptive effect in acetic acid--acetylcholine--and hypertonic saline--induced abdominal constrictions, but not in hot-plate and tail flick tests. P. alliacea did not produce any CNS depressor effect. Thus its antinociceptive action in animals can be responsible by its popular use as an analgesic.

Mechanisms of Microgravity Effect on Vascular Function

NASA Technical Reports Server (NTRS)

Purdy, Ralph E.

1995-01-01

The overall goal of the project is to characterize the effects of simulated microgravity on vascular function. Microgravity is simulated using the hindlimb unweighted (HU) rat, and the following vessels are removed from HU and paired control rats for in vitro analysis: abdominal aorta, carotid and femoral arteries, jugular and femoral veins. These vessels are cut into 3 mm long rings and mounted in tissue baths for the measurement of either isometric contraction, or relaxation of pre- contracted vessels. The isolated mesenteric vascular bed is perfused for the measurement of changes in perfusion pressure as an index of arteriolar constriction or dilation. This report presents, in addition to the statement of the overall goal of the project, a summary list of the specific hypotheses to be tested. These are followed by sections on results, conclusions, significance and plans for the next year.

Efficacy of advice from healthcare professionals to pregnant women on avoiding constrictive clothing around the trunk: a study protocol for a randomised controlled trial

PubMed Central

Takehara, Kenji; Kato, Sachiko; Sasaki, Aiko; Jwa, Seung Chik; Kakee, Naoko; Sago, Haruhiko; Noguchi, Yuko; Aoki, Tomoko; Inoue, Eisuke; Nitta, Chieko; Ishii, Yumiko

2015-01-01

Introduction As a component of midwife care, eliminating clothing that constricts the trunk has been shown to markedly elevate the uterine fundus, soften the uterus and abdomen, and reduce the abdominal wall tension in women admitted to hospital due to the risk of miscarriage or premature delivery. However, no prospective study has conclusively verified the efficacy of avoiding constrictive clothes around the trunk in pregnant women. We aim to verify the efficacy of instructing pregnant women to wear loose clothing that does not constrict the trunk to reduce the risk of premature birth and improve quality of life (QoL) during pregnancy. Methods and analysis We will conduct a randomised controlled trial of pregnant women scheduled to deliver at the National Center for Child Health and Development in Tokyo, Japan. A total of 616 pregnant women, from whom written informed consent will be obtained, will be allocated randomly to an intervention group or a control group. Women in the control group will be provided with anaemia prevention leaflets at 20 weeks’ gestation and skin-care leaflets at 30 weeks’ gestation. Women in the intervention group will be provided with the same leaflets and will also receive health advice from health professionals to avoid constrictive clothing around the trunk. The primary outcome will be a difference between these groups in the frequency of any one of the following category variables: (1) cervical length <30 mm up to 28 weeks’ gestation, (2) hospital admission for threatened premature delivery, or (3) premature delivery. Secondary outcomes will include QoL during pregnancy, maternal state of health, and status of fetal development. Ethics and dissemination The Institutional Review Board and Ethics Committee at the National Center for Child Health and Development, Japan, has approved this study. Our findings will be widely disseminated through conference presentations and peer-reviewed publications. Trial registration number UMIN000016853. PMID:26423851

Design and Development of Variable-Load Energy Absorbers

DTIC Science & Technology

1981-06-16

Three concepts were developed and/or tested: a wire - bending mechanism, a tube-constricting mechanism, and a hydraulic energy absorber. Preliminary full...scale working models of the wire - bending mechanism and the tube-constricting mechanisms were built and tested. The hydraulic energy absorber was

Baclofen reversed thermal place preference in rats with chronic constriction injury.

PubMed

Salte, K; Lea, G; Franek, M; Vaculin, S

2016-06-20

Chronic constriction injury to the sciatic nerve was used as an animal model of neuropathic pain. Instead of frequently used reflex-based tests we used an operant thermal place preference test to evaluate signs of neuropathic pain and the effect of baclofen administration in rats with neuropathy. Chronic constriction injury was induced by four loose ligations of the sciatic nerve. Thermal place preference (45 °C vs. 22 °C and 45 °C vs. 11 °C) was measured after the ligation and after the administration of baclofen in sham and experimental rats. Rats with the chronic constriction injury spent significantly less time on the colder plate compared to sham operated animals at the combination 45 °C vs. 11 °C. After administration of baclofen (10 mg/kg s.c.), the aversion to the colder plate in rats with chronic constriction injury disappeared. At the combination 45 °C vs. 22 °C, no difference in time spent on colder and/or warmer plate was found between sham and experimental animals. These findings show the importance of cold allodynia evaluation in rats with chronic constriction injury and the effectiveness of baclofen in this neuropathic pain model.

Pressure Change in an Arterial Constriction

ERIC Educational Resources Information Center

Mungan, Carl E.

2015-01-01

Consider the following ConcepTest. A platelet is drifting with the blood flowing through a horizontal artery. As the platelet enters a constriction, does the blood pressure increase, decrease, or stay the same?

Efficacy of advice from healthcare professionals to pregnant women on avoiding constrictive clothing around the trunk: a study protocol for a randomised controlled trial.

PubMed

Takehara, Kenji; Kato, Sachiko; Sasaki, Aiko; Jwa, Seung Chik; Kakee, Naoko; Sago, Haruhiko; Noguchi, Yuko; Aoki, Tomoko; Inoue, Eisuke; Nitta, Chieko; Ishii, Yumiko

2015-09-30

As a component of midwife care, eliminating clothing that constricts the trunk has been shown to markedly elevate the uterine fundus, soften the uterus and abdomen, and reduce the abdominal wall tension in women admitted to hospital due to the risk of miscarriage or premature delivery. However, no prospective study has conclusively verified the efficacy of avoiding constrictive clothes around the trunk in pregnant women. We aim to verify the efficacy of instructing pregnant women to wear loose clothing that does not constrict the trunk to reduce the risk of premature birth and improve quality of life (QoL) during pregnancy. We will conduct a randomised controlled trial of pregnant women scheduled to deliver at the National Center for Child Health and Development in Tokyo, Japan. A total of 616 pregnant women, from whom written informed consent will be obtained, will be allocated randomly to an intervention group or a control group. Women in the control group will be provided with anaemia prevention leaflets at 20 weeks' gestation and skin-care leaflets at 30 weeks' gestation. Women in the intervention group will be provided with the same leaflets and will also receive health advice from health professionals to avoid constrictive clothing around the trunk. The primary outcome will be a difference between these groups in the frequency of any one of the following category variables: (1) cervical length <30 mm up to 28 weeks' gestation, (2) hospital admission for threatened premature delivery, or (3) premature delivery. Secondary outcomes will include QoL during pregnancy, maternal state of health, and status of fetal development. The Institutional Review Board and Ethics Committee at the National Center for Child Health and Development, Japan, has approved this study. Our findings will be widely disseminated through conference presentations and peer-reviewed publications. UMIN000016853. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Cardiac magnetic resonance radiofrequency tissue tagging for diagnosis of constrictive pericarditis: A proof of concept study.

PubMed

Power, John A; Thompson, Diane V; Rayarao, Geetha; Doyle, Mark; Biederman, Robert W W

2016-05-01

Invasive cardiac catheterization is the venerable "gold standard" for diagnosing constrictive pericarditis. However, its sensitivity and specificity vary dramatically from center to center. Given the ability to unequivocally define segments of the pericardium with the heart via radiofrequency tissue tagging, we hypothesize that cardiac magnetic resonance has the capability to be the new gold standard. All patients who were referred for cardiac magnetic resonance evaluation of constrictive pericarditis underwent cardiac magnetic resonance radiofrequency tissue tagging to define visceral-parietal pericardial adherence to determine constriction. This was then compared with intraoperative surgical findings. Likewise, all preoperative cardiac catheterization testing was reviewed in a blinded manner. A total of 120 patients were referred for clinical suspicion of constrictive pericarditis. Thirty-nine patients were defined as constrictive pericarditis positive solely via radiofrequency tissue-tagging cardiac magnetic resonance, of whom 21 were positive, 4 were negative, and 1 was equivocal for constrictive pericarditis, as defined by cardiac catheterization. Of these patients, 16 underwent pericardiectomy and were surgically confirmed. There was 100% agreement between cardiac magnetic resonance-defined constrictive pericarditis positivity and postsurgical findings. No patients were misclassified by cardiac magnetic resonance. In regard to the remaining constrictive pericarditis-positive patients defined by cardiac magnetic resonance, 10 were treated medically, declined, were ineligible for surgery, or were lost to follow-up. Long-term follow-up of those who were constrictive pericarditis negative by cardiac magnetic resonance showed no early or late crossover to the surgery arm. Cardiac magnetic resonance via radiofrequency tissue tagging offers a unique, efficient, and effective manner of defining clinically and surgically relevant constrictive pericarditis. Specifically, no patient who was identified with constriction via cardiac magnetic resonance underwent inappropriate sternotomy. However, catheterization had substantial and unacceptable false-positive and false-negative rates with important clinical ramifications. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salomon, G.; Park, E.J.; Quock, R.M.

This study was conducted to identify the opioid receptor subtype(s) responsible for RFR-induced analgesia. Male Swiss Webster mice, 20-25 g, were exposed to 20 mW/cm{sup 2} RFR in a 2,450-MHz waveguide system for 10 min, then tested 15 min later in the abdominal constriction paradigm which detects {mu}- and {kappa}-opioid activity. Immediately following RFR exposure, different groups of mice were pretreated intracerebroventricularly with different opioid receptor blockers with selectivity for {mu}- or {kappa}-opioid receptors. Results show that RFR-induced analgesia was attenuated by higher but not lower doses of the non-selective antagonist naloxone, but the selective {mu}-opioid antagonist {beta}-funaltrexamine and bymore » the selective {kappa}-opioid antagonist norbinaltorphimine. RFR-induced analgesia was also reduced by subcutaneous pretreatment with 5.0 mg/kg of the {mu}-/{kappa}-opioid antagonist({minus})-5,9-diethyl-{alpha}-5,9-dialkyl-2{prime}-hydroxy-6,7-benzomorphan(MR-2266). These findings suggest that RFR-induced analgesia may be mediated by both {mu}- and {kappa}-opioid mechanisms.« less

Diagnostic Challenges in Chronic Constrictive Pericarditis.

PubMed

Braga, Ana; Oliveira, Afonso; Domingues, Kevin; Andrade, Maria João; Abecacis, Miguel; Neves, José Pedro

2017-01-01

Chronic constrictive pericarditis (CCP) is a disease that has multiple possible causes and is associated with variable clinical findings, depending on its severity. It develops insidiously, and in many cases, particularly in developed countries, no antecedent diagnosis can be found. These cases are termed idiopathic. Tuberculosis is the leading cause of constrictive pericarditis in developing nations but represents only a small minority in developed countries. Here the authors describe two different case reports where tuberculosis was the probable cause of CCP. A 21-year-old man born in Cape Verde living in Europe for 4 years and a 24-year-old man born in Guiné Bissau were both admitted due to intense precordial pain and syncope after exertion. Interestingly both had fatigability, dyspnea, chest discomfort and palpitations on exertion, as well as progressive involuntary weight loss and decubitus cough. On physical examination they had tachycardia, jaundice, cachexia, elevated jugular venous pressure, hepatomegaly and ascites. Both electrocardiograms showed prominent P waves and chest X-ray showed bilateral pulmonary interstitial infiltrates and enlargement of the right cavities. Analytically, elevated bilirubin, leukopenia and thrombocytopenia was also found in both. Echocardiography revealed findings, in both cases, compatible with CCP including less common signs as annulus reversus and annulus paradoxus. Thoraco-abdomino-pelvic CT from both patients revealed chronic liver disease with congestion, pleural effusion, pericardial calcifications, ascites and massive mediastinal and abdominal adenopathies. Blood cultures and IGRA test were negative. However, given the presumptive diagnosis of tuberculosis (TB), anti-TB therapy was started. Despite the diagnosis of "end-stage" CCP with very high operative risk multidisciplinary team decided after informed consent, to perform total anterior pericardiectomy, that occurred without complications. Pericardial and mediastinal biopsies, pericardial/pleural fluid cultures/ immune-phenotyping were inconclusive. Anti- tuberculosis therapy was maintained. After surgery, the patients had a remarkable clinical improvement (NYHA I) that persisted in 6- month follow-up. These two case reports illustrate that despite the markedly elevated operative risk of pericardiectomy in "end-stage" forms of disease after patients informed consent must be a considered option. The other point to consider is that, despite rare, tuberculosis still is a possible diagnosis to consider in CCP in Portugal.

Management of the Amniotic Band Syndrome with Cleft Palate: Literature Review and Report of a Case

PubMed Central

Cortez-Ortega, Carolina; Flores-Velázquez, Joselín; Ruiz-Rodríguez, Socorro; Noyola-Frías, Miguel Ángel; Santos-Díaz, Miguel Ángel

2017-01-01

Amniotic Band Syndrome (ABS) is a group of congenital malformations that includes the majority of typical constriction rings and limb and digital amputations, together with major craniofacial, thoracic, and abdominal malformations. The syndrome is caused by early rupture of the amniotic sac. Some of the main oral manifestations include micrognathia, hyperdontia, and cleft lip with or without cleft palate, which is present in 14.6% of patients with this syndrome. The purpose of this report was to describe the clinical characteristics and the oral treatment provided to a 6-month-old male patient affected with ABS with cleft lip and palate. PMID:28246561

Studies in Hawaiian Diptera III: New Distributional Records for Canacidae and a New Endemic Species of Procanace

PubMed Central

2016-01-01

Abstract The distributions of Hawaiian Canacidae, comprising nearly 800 individual collection events, are reviewed and a total of four new island records are reported. These include Canaceoides angulatus from Kahoolawae and Procanace bifurcata from Molokai and Maui, and Procanace constricta from Oahu. A new species from Kauai, Procanace hardyi O'Grady and Pak, is described. This species is closely related to P. constricta from Oahu, Maui, Molokai and Hawaii and shares a similar constriction of the abdomen between tergites four and five but differs in the configuration of the seventh abdominal tergite. Detailed distribution maps for all species are included. PMID:27226743

Minoxidil accelerates heart failure development in rats with ascending aortic constriction.

PubMed

Turcani, M; Jacob, R

1998-06-01

To test the ability of the heart to express characteristic geometric features of concentric and eccentric hypertrophy concurrently, constriction of the ascending aorta was performed in 4-week-old rats. Simultaneously, these rats were treated with an arteriolar dilator minoxidil. An examination 6 weeks after induction of the hemodynamic overload revealed no signs of congestion in systemic or pulmonary circulation in rats with aortic constriction or minoxidil-treated sham-operated rats. The magnitude of hemodynamic overload caused by aortic constriction or minoxidil treatment could be considered as equivalent, because the same enlargement of left ventricular pressure-volume area was necessary to compensate for either pressure or volume overload. Myocardial contractility decreased in rats with aortic constriction, and the compensation was achieved wholly by the marked concentric hypertrophy. Volume overload in minoxidil-treated rats was compensated partially by the eccentric hypertrophy and partially by the increased myocardial contractility. In contrast, increased lung weight and pleural effusion were found in all minoxidil-treated rats with aortic constriction. Unfavorable changes in left ventricular mass and geometry, relatively high chamber stiffness, and depressed ventricular and myocardial function were responsible for the massive pulmonary congestion.

Anti-inflammatory and antinociceptive properties of blueberry extract (Vaccinium corymbosum).

PubMed

Torri, Eliane; Lemos, Marivane; Caliari, Vinícius; Kassuya, Cândida A L; Bastos, Jairo K; Andrade, Sérgio F

2007-04-01

Blueberries are among the edible fruits that are recognized best for their potential health benefits. The crude extract from Vaccinium corymbosum was assessed in anti-inflammatory and antinociceptive models. The crude hydroalcoholic extract was administered orally at doses of 100, 200 or 300 mg kg (-1) for all the assays. In the carrageenan test, the crude extract reduced rat paw oedema by 9.8, 28.5 and 65.9%, respectively. For the histamine assay, the reductions of oedema were 70.1, 71.7 and 81.9%, respectively. In the myeloperoxidase (MPO) assay, 300 mg kg (-1) crude extract produced a significant inhibition of the MPO activity, at 6 h and 24 h after injection of carrageenan, by 42.8 and 46.2%, respectively. With the granulomatous tissue assay dexamethasone displayed significant activity, whereas the blueberry extract was inactive. For the abdominal constriction test, inhibitions of 49.0, 54.5, 53.5%, respectively, were observed for the crude extract, and 61.4% for indometacin. In the formalin test, the crude extract (200 and 300 mg kg (-1)) and indometacin inhibited only the second phase by 36.2, 35.3 and 45.8%, respectively. Considering that the crude extract of blueberry displayed antinociceptive and anti-inflammatory activity, its consumption may be helpful for the treatment of inflammatory disorders.

Mast cell mediators in citric acid-induced airway constriction of guinea pigs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, C.-H.; Lai, Y.-L.

2005-08-15

We demonstrated previously that mast cells play an important role in citric acid (CA)-induced airway constriction. In this study, we further investigated the underlying mediator(s) for this type of airway constriction. At first, to examine effects caused by blocking agents, 67 young Hartley guinea pigs were divided into 7 groups: saline + CA; methysergide (serotonin receptor antagonist) + CA; MK-886 (leukotriene synthesis inhibitor) + CA; mepyramine (histamine H{sub 1} receptor antagonist) + CA; indomethacin (cyclooxygenase inhibitor) + CA; cromolyn sodium (mast cell stabilizer) + CA; and compound 48/80 (mast cell degranulating agent) + CA. Then, we tested whether leukotriene C{submore » 4} (LTC{sub 4}) or histamine enhances CA-induced airway constriction in compound 48/80-pretreated guinea pigs. We measured dynamic respiratory compliance (Crs) and forced expiratory volume in 0.1 s (FEV{sub 0.1}) during either baseline or recovery period. In addition, we detected histamine level, an index of pulmonary mast cell degranulation, in bronchoalveolar lavage (BAL) samples. Citric acid aerosol inhalation caused decreases in Crs and FEV{sub 0.1}, indicating airway constriction in the control group. This airway constriction was significantly attenuated by MK-886, mepyramine, cromolyn sodium, and compound 48/80, but not by either methysergide or indomethacin. Both LTC{sub 4} and histamine infusion significantly increased the magnitude of CA-induced airway constriction in compound 48/80-pretreated guinea pigs. Citric acid inhalation caused significant increase in histamine level in the BAL sample, which was significantly suppressed by compound 48/80. These results suggest that leukotrienes and histamine originating from mast cells play an important role in CA inhalation-induced noncholinergic airway constriction.« less

Purulent Pericarditis after Liver Abscess: A Case Report

PubMed Central

Fidalgo García, María; Rodríguez Sanjuán, Juan Carlos; Riaño Molleda, María; González Andaluz, Marta; Real Noval, Hector; Gómez Fleitas, Manuel

2014-01-01

We present the case of a 49-year-old woman, with previous clinical antecedents of recent hepatic metastasis, who was admitted to the ICU due to respiratory failure and hemodynamic instability. She was found to have purulent pericarditis complicated by pericardial tamponade and pleural effusion, as well as surgical site infection, which was the origin of the disease. Cultures of the surgical wound and the pericardial effusion were positive for Enterococcus faecalis and Escherichia coli. A pericardial tap was performed and the intra-abdominal abscess was surgically drained. Pleural effusion was also evacuated. She received antibiotic treatment and recovered successfully. The only after-effect was a well-tolerated effusive-constrictive pericarditis. PMID:24872819

Overexpression of SARAF Ameliorates Pressure Overload-Induced Cardiac Hypertrophy Through Suppressing STIM1-Orai1 in Mice.

PubMed

Dai, Fengdan; Zhang, Yan; Wang, Qiang; Li, De; Yang, Yongjian; Ma, Shuangtao; Yang, Dachun

2018-01-01

Activation of stromal interaction molecule 1 (STIM1) and Orai1 participates in the development of cardiac hypertrophy. Store-operated Ca2+ entry-associated regulatory factor (SARAF) is an intrinsic inhibitor of STIM1-Orai1 interaction. Thus, we hypothesized that SARAF could prevent cardiac hypertrophy. Male C57BL/6 mice, aged 8 weeks, were randomly divided into sham and abdominal aortic constriction surgery groups and were infected with lentiviruses expressing SARAF and GFP (Lenti-SARAF) or GFP alone (Lenti-GFP) via intramyocardial injection. At 4 weeks after aortic constriction, left ventricular structure and function were assessed by echocardiography and hemodynamic assays. The gene and protein expressions of SARAF, STIM1, and Orai1 were measured by quantitative PCR and Western blot, respectively. Gene and protein expressions of SARAF were significantly decreased, while STIM1 and Orai1 were increased in the heart tissue compared with sham group. Overexpression of SARAF in the heart prevented the upregulation of STIM1 and Orai1, and importantly, attenuated aortic constriction-induced decrease in maximal rate of left ventricular pressure decay and increases in thickness of interventricular septum and left ventricular posterior wall, heart weight/body weight ratio, and size of cardiomyocytes. Blood pressure detected through the carotid artery and left ventricular systolic function were not affected by SARAF overexpression. In addition, overexpression of SARAF also attenuated angiotensin II-induced upregulation of STIM1 and Orai1 and hypertrophy of cultured cardiomyocytes. Overexpression of SARAF in the heart prevents cardiac hypertrophy, probably through suppressing the upregulation of STIM1/Orai1. © 2018 The Author(s). Published by S. Karger AG, Basel.

Test of the movement expansion model: Anticipatory vowel lip protrusion and constriction in French and English speakers

PubMed Central

Noiray, Aude; Cathiard, Marie-Agnès; Ménard, Lucie; Abry, Christian

2011-01-01

The modeling of anticipatory coarticulation has been the subject of longstanding debates for more than 40 yr. Empirical investigations in the articulatory domain have converged toward two extreme modeling approaches: a maximal anticipation behavior (Look-ahead model) or a fixed pattern (Time-locked model). However, empirical support for any of these models has been hardly conclusive, both within and across languages. The present study tested the temporal organization of vocalic anticipatory coarticulation of the rounding feature from [i] to [u] transitions for adult speakers of American English and Canadian French. Articulatory data were synchronously recorded using an Optotrak for lip protrusion and a dedicated Lip-Shape-Tracking-System for lip constriction. Results show that (i) protrusion is an inconsistent parameter for tracking anticipatory rounding gestures across individuals, more specifically in English; (ii) labial constriction (between-lip area) is a more reliable correlate, allowing for the description of vocalic rounding in both languages; (iii) when tested on the constriction component, speakers show a lawful anticipatory behavior expanding linearly as the intervocalic consonant interval increases from 0 to 5 consonants. The Movement Expansion Model from Abry and Lallouache [(1995a) Bul. de la Comm. Parlée 3, 85–99; (1995b) Proceedings of ICPHS4, 152–155.] predicted such a regular behavior, i.e., a lawful variabilitywith a speaker-specific expansion rate, which is not language-specific. PMID:21303015

Test of the movement expansion model: anticipatory vowel lip protrusion and constriction in French and English speakers.

PubMed

Noiray, Aude; Cathiard, Marie-Agnès; Ménard, Lucie; Abry, Christian

2011-01-01

The modeling of anticipatory coarticulation has been the subject of longstanding debates for more than 40 yr. Empirical investigations in the articulatory domain have converged toward two extreme modeling approaches: a maximal anticipation behavior (Look-ahead model) or a fixed pattern (Time-locked model). However, empirical support for any of these models has been hardly conclusive, both within and across languages. The present study tested the temporal organization of vocalic anticipatory coarticulation of the rounding feature from [i] to [u] transitions for adult speakers of American English and Canadian French. Articulatory data were synchronously recorded using an Optotrak for lip protrusion and a dedicated Lip-Shape-Tracking-System for lip constriction. Results show that (i) protrusion is an inconsistent parameter for tracking anticipatory rounding gestures across individuals, more specifically in English; (ii) labial constriction (between-lip area) is a more reliable correlate, allowing for the description of vocalic rounding in both languages; (iii) when tested on the constriction component, speakers show a lawful anticipatory behavior expanding linearly as the intervocalic consonant interval increases from 0 to 5 consonants. The Movement Expansion Model from Abry and Lallouache [(1995a) Bul. de la Comm. Parlée 3, 85-99; (1995b) Proceedings of ICPHS 4, 152-155.] predicted such a regular behavior, i.e., a lawful variability with a speaker-specific expansion rate, which is not language-specific.

Division of constricted and urethane-treated sand dollar eggs: a test of the polar stimulation hypothesis.

PubMed

Rappaport, R; Rappaport, B N

1984-07-01

In spherical cells with a central mitotic apparatus, the centers of the asters are closer to the poles than to the equator. This circumstance is basic to several hypothetical explanations of the way in which the mitotic apparatus establishes the division mechanism. This investigation was designed to determine whether that geometrical relationship is necessary for division. Fertilized, mechanically denuded sand dollar eggs were inserted into glass loops, which reduced the diameter in the constriction plane from the normal 142 to 78-80 microns and partly constricted the cell into equal parts. The mitotic apparatus straddled the constriction, and its length was not significantly changed. The manipulation increased the distance from the astral centers to the poles and decreased the distance from the astral centers to the equator to a degree that reversed the normal distance relations. These cells divided normally. Ethyl urethane (0.06 M) reduces the size of the mitotic apparatus and blocks cleavage in spherical cells. When treated cells are confined in 80-microns i.d. capillaries, they divide. Treated cells also divide when they are constricted by an 80-microns i.d. glass loop if the mitotic apparatus straddles the constriction. An equal degree of constriction in the subfurrow and subpolar areas did not reverse the effect of urethane. The results demonstrate that cleavage does not depend on the normal distance relation between the mitotic apparatus and the poles, and that the urethane effect can be remedied only by reducing the distance between the mitotic apparatus and the equatorial surface. Both findings are inconsistent with the polar stimulation hypothesis.

Reconstruction of Moderately Constricted Ears by Combining V-Y Advancement of Helical Root, Conchal Cartilage Graft, and Mastoid Hitch.

PubMed

Elshahat, Ahmed; Lashin, Riham

2016-01-01

Despite the multitude of corrective procedures described in the literature, adequate surgical correction of the congenital constricted ear remains a challenge. The maintenance of the shape and size of the reconstructed upper neohelix poses a particular problem. In the present study, a total of 12 cases of reconstruction were undertaken. All of them were moderate (type IIA Tanzer classification) deformities. A combined procedure was adopted using a V-Y advancement of the helical root, cartilage scoring, and cartilage grafting from the contralateral concha to reconstruct the upper helix. A mastoid hitch was used as an adjunct to these procedures to maintain helical elevation and prevent recurrence. Mean follow-up period was 6 months. RESULTS were excellent (n = 7), good (n = 4), and fair (n = 1). Paired t test showed a significant increase in the height of the constricted ear postoperatively (P < .001) and a nonsignificant difference between the height of the constricted and contralateral ears postoperatively (P > .05). Apart from dislodgment of the mastoid hitch suture in 1 patient, no complications were recorded. This combined technique is useful in correcting moderately constricted ear deformities.

Transpalatal distraction for the management of maxillary constriction in pediatric patients.

PubMed

Adolphs, Nicolai; Ernst, Nicole; Hoffmeister, Bodo; Raguse, Jan-Dirk

2015-01-01

The management of severe maxillary constriction can be challenging. For that purpose surgically assisted maxillary expansion by transpalatal distraction (TPD) can typically be recommended after skeletal maturity. However in selected cases bone borne transpalatal distraction devices can contribute to improve maxillary constriction considerably earlier already during mixed dentition. To assess the possibility of bone borne transpalatal distraction in pediatric patients. Clinical paper. Since 2010 TPD has been applied to six pediatric patients during mixed dentition when severe maxillary constriction was present and conventional orthodontic widening has already failed. Individually selected devices (Surgitec, Belgium) were inserted in general anaesthesia and distraction was performed according to well known parameters. Maxillary constriction could be improved in all six patients without any drawbacks by bone borne devices during mixed dentition. Skeletal conditions were obviously improved for subsequent orthodontic or orthognathic therapy without functional impairment. Follow-up is up to 36 months after device removal. Transpalatal Distraction is recommendable in selected pediatric patients if massive growth disturbance is present or has to be expected. TPD allows for individually adapted maxillary expansion by selection and positioning of appropriate devices in combination with intraoperative testing of maxillary movements and controlled bone removal.

Beneficial role of tamoxifen in experimentally induced cardiac hypertrophy.

PubMed

Patel, Bhoomika M; Desai, Vishal J

2014-04-01

Protein kinase C (PKC) activation is associated with cardiac hypertrophy (CH), fibrosis, inflammation and cardiac dysfunction. Tamoxifen is a PKC inhibitor. Despite these, reports on effect of tamoxifen on cardiac hypertrophy are not available. Hence, we have investigated effect of tamoxifen (2mg/kg/day, po) on CH. In isoproterenol (ISO) induced CH, ISO (5mg/kg/day, ip) was administered for 10 days in Wistar rats. For partial abdominal aortic constriction (PAAC), abdominal aorta was ligated by 4-0 silk thread around 7.0mm diameter blunt needle. Then the needle was removed to leave the aorta partially constricted for 30 days. Tamoxifen was given for 10 days and 30 days, respectively, in ISO and PAAC models and at end of each studies, animals were sacrificed and biochemical and cardiac parameters were evaluated. ISO and PAAC produced significant dyslipidemia, hypertension, bradycardia, oxidative stress and increase in serum lactate dehydrogenase and creatine kinase-MB, C-reactive protein. Treatment with tamoxifen significantly controlled dyslipidemia, hypertension, bradycardia, oxidative stress and reduced serum cardiac markers. ISO control and PAAC control rats exhibited significantly increased cardiac and left ventricular (LV) hypertrophic index, LV thickness, cardiomyocyte diameter. Treatment with tamoxifen significantly reduced these hypertrophic indices. There was a significant increase in LV collagen level, decrease in Na(+)K(+)ATPase activity, and reduction in the rate of pressure development and decay. Tamoxifen significantly reduced LV collagen, increased Na(+)K(+)ATPase activity and improved hemodynamic function. This was further supported by histopathological studies, in which tamoxifen showed marked decrease in fibrosis and increase in extracellular spaces in the treated animals. Our data suggest that tamoxifen produces beneficial effects on cardiac hypertrophy and hence may be considered as a preventive measure for cardiac hypertrophy. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Novel experimental model of pressure overload hypertrophy in rats.

PubMed

Molina, Ezequiel J; Gupta, Dipin; Palma, Jon; Torres, Denise; Gaughan, John P; Houser, Steven; Macha, Mahender

2009-05-15

We studied a novel animal model of pressure overload hypertrophy in transition to heart failure following ascending aortic constriction. We sought to assess chronologic changes in hemodynamic parameters, echocardiographic signs of left ventricular (LV) remodeling, exercise tolerance, and profiles of systemic and local inflammation. A cohort of Sprague Dawley rats underwent aortic constriction proximal to the innominate artery and were followed by echocardiography. A group of animals were euthanized 20 wk after aortic constriction, before any detectable decline in fractional shortening (normal fractional shortening (FS) or control group; n = 6). When additional animals reached an absolute 25% decline in fractional shortening, they were randomized to be euthanized on d 0 (25% downward arrow FS group; n = 5), or d 21 (>25% downward arrow FS group; n = 6). Hemodynamic and echocardiographic assessment, swim testing to exhaustion, and measurement of systemic and local inflammatory markers was performed at each time interval. An absolute decline of 25% in FS after aortic constriction was observed between 24 and 28 wk for most animals. The transition from compensated to decompensated hypertrophy was associated with markedly decreased dP/dt(max) and dP/dt(min), increased LV end-systolic diameter and LV end-diastolic diameter, stabilization of LV free wall diameter, decreased exercise performance and up-regulation in expression of interleukin-1, interleukin-6, tumor necrosis factor-alpha, and atrial natriuretic peptide. All animals developed heart failure. This study demonstrates that proximal aortic constriction in young rats represents an excellent experimental model of pressure overload hypertrophy that may be useful for testing the efficacy of novel therapies for the treatment of heart failure.

Vinpocetine and piracetam exert antinociceptive effect in visceral pain model in mice.

PubMed

Abdel Salam, Omar M E

2006-01-01

The effect of vinpocetine or piracetam on thermal and visceral pain was studied in mice. In the hot plate test, vinpocetine (0.9 and 1.8 mg/kg), but not piracetam, produced a reduction in nociceptive response. Vinpocetine (0.45-1.8 mg/kg, ip) or piracetam (75-300 mg/kg, ip) caused dose-dependent inhibition of the abdominal constrictions evoked by ip injection of acetic acid. The effect of vinpocetine or piracetam was markedly potentiated by co-administration of propranolol, guanethidine, atropine, naloxone, yohimbine or prazosin. The marked potentiation of antinociception occurred upon a co-administration of vinpocetine and baclofen (5 or 10 mg/kg). In contrast, piracetam antagonized antinociception caused by the low (5 mg/kg), but not the high (10 mg/kg) dose of baclofen. The antinociception caused by vinpocetine was reduced by sulpiride; while that of piracetam was enhanced by haloperidol or sulpiride. Either vinpocetine or piracetam enhanced antinociception caused by imipramine. The antinociceptive effects of vinpocetine or piracetam were blocked by prior administration of theophylline. Low doses of either vinpocetine or piracetam reduced immobility time in the Porsolt's forced-swimming test. This study indicates that vinpocetine and piracetam possess visceral antinociceptive properties. This effect depends on activation of adenosine receptors. Piracetam in addition inhibits GABA-mediated antinociception.

A new species of the genus Obolopteryx Cohn et al. 2014 and a conspecific
gynandromorph (Ensifera: Tettigoniidae: Phaneropterinae).

PubMed

Barrientos-Lozano, Ludivina; Rocha-Sánchez, Aurora Y; Correa-Sandoval, Alfonso

2015-10-12

Obolopteryx truncoangulata n. sp., Barrientos-Lozano & Rocha-Sánchez, and a field collected conspecific gynandromorph are described, both from the northern Mexico's Highland. O. truncoangulata n. sp., may be separated from congeneric O. brevihastata based on morphological characters. The male's pronotum is more constricted mesally, and the tegmina are shorter. The disto-dorsal abdominal tergites sub-triangular projection broadly bilobated. Cerci broader proximally, and thumb and shaft more robust and shorter; subgenital plate deep "U" shape emarginated distally, lateral angles excised about mid portion. In females, tegmina, ovipositor, subgenital plate and basal sclerites are of different shape than analogous structures in O. brevihastata. Information on geographic distribution and ecology is provided.

Severe Craniofacial Involvement due to Amniotic Band Sequence.

PubMed

Becerra-Solano, Luis Eduardo; Castañeda-Cisneros, Gema; Corona-Rivera, Jorge Roman; Díaz-Rodríguez, Manuel; Figuera, Luis Eduardo; López-Muñoz, Eunice; Nastasi-Catanese, José Antonio; Toscano-Flores, José Jesús; Ramírez-Dueñas, María de Lourdes; García-Ortíz, José Elias

2018-02-01

Disruptive amniotic band sequence (DABS) is a sporadic, non-familial disorder with unclear etiology. Diagnosis is based on clinical features because there is currently no reliable laboratory diagnostic tests. We describe six cases of DABS with severe craniofacial deformations, three with and three without classical constrictive limb deformation. The craniofacial deformities were delimited by peripheral sharply demarcated scarring. When a sharply demarcated linear disruptive craniofacial lesion is observed, DABS should be considered despite the absence of constrictive limb scarring.

Myogenic constriction is increased in mesenteric resistance arteries from rats with chronic heart failure: instantaneous counteraction by acute AT1 receptor blockade

PubMed Central

Gschwend, S; Henning, R H; Pinto, Y M; de Zeeuw, D; van Gilst, W H; Buikema, H

2003-01-01

Increased vascular resistance in chronic heart failure (CHF) has been attributed to stimulated neurohumoral systems. However, local mechanisms may also importantly contribute to set arterial tone. Our aim, therefore, was to test whether pressure-induced myogenic constriction of resistance arteries in vitro – devoid of acute effects of circulating factors – is increased in CHF and to explore underlying mechanisms. At 12 weeks after coronary ligation-induced myocardial infarction or SHAM-operations in rats, we studied isolated mesenteric arteries for myogenic constriction, determined as the active constriction (% of passive diameter) in response to stepwise increase in intraluminal pressure (20 – 160 mmHg), in the absence and presence of inhibitors of potentially involved modulators of myogenic constriction. We found that myogenic constriction in mesenteric arteries from CHF rats was markedly increased compared to SHAM over the whole pressure range, the difference being most pronounced at 60 mmHg (24±2 versus 4±3%, respectively, P<0.001). Both removal of the endothelium as well as inhibition of NO production (L-NG-monomethylarginine, 100 μM) significantly increased myogenic constriction (+16 and +25%, respectively), the increase being similar in CHF- and SHAM-arteries (P=NS). Neither endothelin type A (ETA)-receptor blockade (BQ123, 1 μM) nor inhibition of perivascular (sympathetic) nerve conduction (tetrodotoxin, 100 nM) affected the myogenic response in either group. Interestingly, increased myogenic constriction in CHF was fully reversed after angiotensin II type I (AT1)-receptor blockade (candesartan, 100 nM; losartan, 10 μM), which was without effect in SHAM. In contrast, neither angiotensin-converting enzyme (ACE) inhibition (lisinopril, 1 μM; captopril, 10 μM) or AT2-receptor blockade (PD123319, 1 μM), nor inhibition of superoxide production (superoxide dismutase, 50 U ml−1), TXA2-receptor blockade (SQ29,548, 1 μM) or inhibition of cyclooxygenase-derived prostaglandins (indomethacin, 10 μM) affected myogenic constriction. Sensitivity of mesenteric arteries to angiotensin II (10 nM – 100 μM) was increased (P<0.05) in CHF (pD2 7.1±0.4) compared to SHAM (pD2 6.2±0.3), while the sensitivity to KCl and phenylephrine was not different. Our results demonstrate increased myogenic constriction in small mesenteric arteries of rats with CHF, potentially making it an important target for therapy in counteracting increased vascular resistance in CHF. Our results further suggest active and instantaneous participation of AT1-receptors in increased myogenic constriction in CHF, involving increased sensitivity of AT1-receptors rather than apparent ACE-mediated local angiotensin II production. PMID:12890711

Naltrexone-sensitive analgesia following exposure of mice to 2450-MHz radiofrequency radiation (RFR)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maillefer, R.H.; Quock, R.M.

1991-03-11

This study was conducted to determine whether exposure to RFR might induce sufficient thermal stress to activate endogenous opioid mechanisms and induce analgesia. Male Swiss Webster mice, 20-25 g, were exposed to 10, 15 or 20 mV/cm{sup 2} RFR in a 2,450-MHz waveguide system for 10 min, then tested in the abdominal constriction paradigm. Specific absorption rates (SAR) were 23.7 W/kg at 10 mW/cm{sup 2}, 34.6 W/kg at 15 mW/cm{sup 2} and 45.5 W/kg at 20 mW/cm{sup 2}. Confinement in the exposure chamber alone did not appreciably alter body temperature but did appear to induce a stress-associated analgesia that wasmore » insensitive to the opioid receptor blocker naltrexone. Exposure of confined mice to RFR elevated body temperature and further increased analgesia in SAR-dependent manner. The high-SAR RFR-induced analgesia, but not the hyperthermia, was reduced by naltrexone. These findings suggest that (1) RFR produces SAR-dependent hyperthermia and analgesia and (2) RFR-induced analgesia is mediated by opioid mechanisms while confinement-induced analgesia involves non-opioid mechanisms.« less

Rapidly progressive effusive constrictive pericarditis caused by methicillin sensitive Staphylococcus aureus (MSSA). samraakhtar@hotmail.com.

PubMed

Akhtar, Naveed; Khalid, Ayesha; Ahmed, Waqas; Rasheed, Khalid

2010-04-01

Effusive-constrictive pericarditis is a clinical syndrome characterized by concurrent pericardial effusion and pericardial constriction, where constrictive hemodynamics are persistent after effusion is drained. It may present at any point along the clinical course, from the occurrence of an effusion to the development of chronic pericardial constriction. We refer an unusual case of effusive constrictive pericarditis developing rapidly within days, following purulent pericarditis secondary to chest trauma.

Embryo as an active granular fluid: stress-coordinated cellular constriction chains

NASA Astrophysics Data System (ADS)

Holcomb, Michael; Gao, Guo-Jie; Thomas, Jeffrey; Blawzdziewicz, Jerzy

2016-11-01

Mechanical stress plays an intricate role in gene expression in individual cells and sculpting of developing tissues. Motivated by our observation of the cellular constriction chains (CCCs) during the initial phase of ventral furrow formation in the Drosophila melanogaster embryo, we propose an active granular fluid (AGF) model that provides valuable insights into cellular coordination in the apical constriction process. In our model, cells are treated as circular particles connected by a predefined force network, and they undergo a random constriction process in which the particle constriction probability P is a function of the stress exerted on the particle by its neighbors. We find that when P favors tensile stress, constricted particles tend to form chain-like structures. In contrast, constricted particles tend to form compact clusters when P favors compression. A remarkable similarity of constricted-particle chains and CCCs observed in vivo provides indirect evidence that tensile-stress feedback coordinates the apical constriction activity.

Reliability of constricted double-heterojunction AlGaAs diode lasers

NASA Technical Reports Server (NTRS)

Botez, D.; Connolly, J. C.; Ettenberg, M.; Gilbert, D. B.; Hughes, J. J.

1983-01-01

Constricted double-heterojunction diode lasers have been life tested at 70 C heatsink temperature and 3-4 mW/facet in CW operation. A median life of 7800 h is obtained at 70 C, which extrapolates to 400,000 h median life at room temperature. The extrapolated mean time to failure at room temperature is in excess of 1,000,000 h. Single-longitudinal-mode CW operation is maintained after 10,000 h of accelerated aging at 70 C.

Stochastic phase of ventral furrow formation in the Drosophila embryo: cellular constriction chains, mechanical feedback, and robustness

NASA Astrophysics Data System (ADS)

Blawzdziewicz, Jerzy; Gao, Guo-Jie J.; Holcomb, Michael C.; Thomas, Jeffrey H.

The key process giving rise to ventral furrow formation (VFF) in Drosophila embryo is apical constriction of cells in the ventral region. The constriction produces negative spontaneous curvature of the cell layer. During the initial slower phase of VFF approximately 40% of cells constrict in a seemingly random order. We show that this initial phase of VFF does not depend on random uncorrelated events. Instead, constricted cell apices form well-defined correlated structures, i.e., cellular constriction chains (CCCs), indicative of strong spatial and directional correlations between the constriction events. We argue that this chain formation is a signature of mechanical signaling that coordinates apical constrictions through tensile stress. To gain insights into the mechanisms involved in this correlated constriction process, we propose an active granular fluid (AGF) model which considers a tissue as a collection of mechanically active, stress-responsive objects. Our AGF molecular dynamics simulations show that cell constriction sensitivity to tensile stress results in formation of CCCs whereas compressive-stress sensitivity leads to compact constricted cell clusters; the CCCs, which can penetrate less-active regions, increase the robustness of the VFF process.

Characterization of superconducting nanowire single-photon detector with artificial constrictions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Ling; Liu, Dengkuan; Wu, Junjie

2014-06-15

Statistical studies on the performance of different superconducting nanowire single-photon detectors (SNSPDs) on one chip suggested that random constrictions existed in the nanowire that were barely registered by scanning electron microscopy. With the aid of advanced e-beam lithography, artificial geometric constrictions were fabricated on SNSPDs as well as single nanowires. In this way, we studied the influence of artificial constrictions on SNSPDs in a straight forward manner. By introducing artificial constrictions with different wire widths in single nanowires, we concluded that the dark counts of SNSPDs originate from a single constriction. Further introducing artificial constrictions in SNSPDs, we studied themore » relationship between detection efficiency and kinetic inductance and the bias current, confirming the hypothesis that constrictions exist in SNSPDs.« less

Numerical Simulations of the Motion and Deformation of Three RBCs during Poiseuille Flow through a Constricted Vessel Using IB-LBM.

PubMed

Wang, Rongyang; Wei, Yikun; Wu, Chuanyu; Sun, Liang; Zheng, Wenguang

2018-01-01

The immersed boundary-lattice Boltzmann method (IB-LBM) was used to examine the motion and deformation of three elastic red blood cells (RBCs) during Poiseuille flow through constricted microchannels. The objective was to determine the effects of the degree of constriction and the Reynolds (Re) number of the flow on the physical characteristics of the RBCs. It was found that, with decreasing constriction ratio, the RBCs experienced greater forced deformation as they squeezed through the constriction area compared to at other parts of the microchannel. It was also observed that a longer time was required for the RBCs to squeeze through a narrower constriction. The RBCs subsequently regained a stable shape and gradually migrated toward the centerline of the flow beyond the constriction area. However, a sick RBC was observed to be incapable of passing through a constricted vessel with a constriction ratio ≤1/3 for Re numbers below 0.40.

Numerical Simulations of the Motion and Deformation of Three RBCs during Poiseuille Flow through a Constricted Vessel Using IB-LBM

PubMed Central

Sun, Liang; Zheng, Wenguang

2018-01-01

The immersed boundary-lattice Boltzmann method (IB-LBM) was used to examine the motion and deformation of three elastic red blood cells (RBCs) during Poiseuille flow through constricted microchannels. The objective was to determine the effects of the degree of constriction and the Reynolds (Re) number of the flow on the physical characteristics of the RBCs. It was found that, with decreasing constriction ratio, the RBCs experienced greater forced deformation as they squeezed through the constriction area compared to at other parts of the microchannel. It was also observed that a longer time was required for the RBCs to squeeze through a narrower constriction. The RBCs subsequently regained a stable shape and gradually migrated toward the centerline of the flow beyond the constriction area. However, a sick RBC was observed to be incapable of passing through a constricted vessel with a constriction ratio ≤1/3 for Re numbers below 0.40. PMID:29681999

Flow of a Casson fluid through a locally-constricted porous channel: a numerical study

NASA Astrophysics Data System (ADS)

Amlimohamadi, Haleh; Akram, Maryammosadat; Sadeghy, Kayvan

2016-05-01

Flow of a Casson fluid through a two-dimensional porous channel containing a local constriction is numerically investigated assuming that the resistance offered by the porous medium obeys the Darcy's law. Treating the constriction as another porous medium which obeys the Darcy-Forcheimer model, the equations governing fluid flow in the main channel and the constriction itself are numerically solved using the finite-volume method (FVM) based on the pseudo-transient SIMPLE algorithm. It is shown that an increase in the porosity of the channel decreases the shear stress exerted on the constriction. On the other hand, an increase in the fluid's yield stress is predicted to increase the maximum shear stress experienced by the constriction near its crest. The porosity of the constriction itself is predicted to have a negligible effect on the plaque's shear stress. But, the momentum of the weak flow passing through the constriction is argued to lower the bulk fluid from separating downstream of the constriction.

Mechanics of Constriction during Cell Division: A Variational Approach

PubMed Central

Almendro-Vedia, Victor G.; Monroy, Francisco; Cao, Francisco J.

2013-01-01

During symmetric division cells undergo large constriction deformations at a stable midcell site. Using a variational approach, we investigate the mechanical route for symmetric constriction by computing the bending energy of deformed vesicles with rotational symmetry. Forces required for constriction are explicitly computed at constant area and constant volume, and their values are found to be determined by cell size and bending modulus. For cell-sized vesicles, considering typical bending modulus of , we calculate constriction forces in the range . The instability of symmetrical constriction is shown and quantified with a characteristic coefficient of the order of , thus evidencing that cells need a robust mechanism to stabilize constriction at midcell. PMID:23990888

Effects of nanosized constriction on thermal transport properties of graphene

PubMed Central

2014-01-01

Thermal transport properties of graphene with nanosized constrictions are investigated using nonequilibrium molecular dynamics simulations. The results show that the nanosized constrictions have a significant influence on the thermal transport properties of graphene. The thermal resistance of the nanosized constrictions is on the order of 107 to 109 K/W at 150 K, which reduces the thermal conductivity by 7.7% to 90.4%. It is also found that the constriction resistance is inversely proportional to the width of the constriction and independent of the heat current. Moreover, we developed an analytical model for the ballistic thermal resistance of the nanosized constrictions in two-dimensional nanosystems. The theoretical prediction agrees well with the simulation results in this paper, which suggests that the thermal transport across the nanosized constrictions in two-dimensional nanosystems is ballistic in nature. PACS 65.80.CK; 61.48.Gh; 63.20.kp; 31.15.xv PMID:25232292

Mechanism of Cytokinetic Contractile Ring Constriction in Fission Yeast

PubMed Central

Stachowiak, Matthew R.; Laplante, Caroline; Chin, Harvey F.; Guirao, Boris; Karatekin, Erdem; Pollard, Thomas D.; O’Shaughnessy, Ben

2014-01-01

SUMMARY Cytokinesis involves constriction of a contractile actomyosin ring. The mechanisms generating ring tension and setting the constriction rate remain unknown, since the organization of the ring is poorly characterized, its tension was rarely measured, and constriction is coupled to other processes. To isolate ring mechanisms we studied fission yeast protoplasts, where constriction occurs without the cell wall. Exploiting the absence of cell wall and actin cortex, we measured ring tension and imaged ring organization, which was dynamic and disordered. Computer simulations based on the amounts and biochemical properties of the key proteins showed that they spontaneously self-organize into a tension-generating bundle. Together with rapid component turnover, the self-organization mechanism continuously reassembles and remodels the constricting ring. Ring constriction depended on cell shape, revealing that the ring operates close to conditions of isometric tension. Thus, the fission yeast ring sets its own tension, but other processes set the constriction rate. PMID:24914559

Adaptation of mesenteric lymphatic vessels to prolonged changes in transmural pressure.

PubMed

Dongaonkar, R M; Nguyen, T L; Quick, C M; Hardy, J; Laine, G A; Wilson, E; Stewart, R H

2013-07-15

In vitro studies have revealed that acute increases in transmural pressure increase lymphatic vessel contractile function. However, adaptive responses to prolonged changes in transmural pressure in vivo have not been reported. Therefore, we developed a novel bovine mesenteric lymphatic partial constriction model to test the hypothesis that lymphatic vessels exposed to higher transmural pressures adapt functionally to become stronger pumps than vessels exposed to lower transmural pressures. Postnodal mesenteric lymphatic vessels were partially constricted for 3 days. On postoperative day 3, constricted vessels were isolated, and divided into upstream (UP) and downstream (DN) segment groups, and instrumented in an isolated bath. Although there were no differences between the passive diameters of the two groups, both diastolic diameter and systolic diameter were significantly larger in the UP group than in the DN group. The pump index of the UP group was also higher than that in the DN group. In conclusion, this is the first work to report how lymphatic vessels adapt to prolonged changes in transmural pressure in vivo. Our results suggest that vessel segments upstream of the constriction adapt to become both better fluid conduits and lymphatic pumps than downstream segments.

DPD simulation on the dynamics of a healthy and infected red blood cell in flow through a constricted channel

NASA Astrophysics Data System (ADS)

Hoque, Sazid Zamal; Anand, D. Vijay; Patnaik, B. S. V.

2017-11-01

The state of the red blood cell (either healthy or infected RBC) will influence its deformation dynamics. Since the pathological condition related to RBC, primarily originates from a single cell infection, therefore, it is important to relate the deformation dynamics to the mechanical properties (such as, bending rigidity and membrane elasticity). In the present study, numerical simulation of a healthy and malaria infected RBC in a constricted channel is analyzed. The flow simulations are carried out using finite sized dissipative particle dynamics (FDPD) method in conjunction with a discrete model that represents the membrane of the RBC. The numerical equivalent of optical tweezers test is validated against the experimental studies. Two different types of constrictions, viz., a converging-diverging type tapered channel and a stenosed microchannel are considered for the simulation. The effect of degree of constriction and the flow rate effect on the RBC is investigated. It was observed that, as the flow rate decreases, the infected RBC completely blocks the micro vessel. The transit time for infected cell drastically increases compared to healthy RBC. Our simulations indicate that, there is a critical flow rate below which infected RBC cannot pass through the micro capillary.

Patterned Ferroelectric Films for Tunable Microwave Devices

NASA Technical Reports Server (NTRS)

Miranda, Felix A.; Mueller, Carl H.

2008-01-01

Tunable microwave devices based on metal terminals connected by thin ferroelectric films can be made to perform better by patterning the films to include suitably dimensioned, positioned, and oriented constrictions. The patterns can be formed during fabrication by means of selective etching processes. If the width of the ferroelectric film in such a device is reduced at one or more locations, then both the microwave field and any applied DC bias (tuning) electric field become concentrated at those locations. The magnitudes of both the permittivity and the dielectric loss of a ferroelectric material are reduced by application of a DC field. Because the concentration of the DC field in the constriction(s) magnifies the permittivity- and loss-reducing effects of the applied DC voltage, the permittivity and dielectric loss in the constriction(s) are smaller in the constriction(s) than they are in the wider parts of the ferroelectric film. Furthermore, inasmuch as displacement current must flow through either the constriction(s) or the low-loss dielectric substrate, the net effect of the constriction(s) is equivalent to that of incorporating one or more low-loss, low-permittivity region(s) in series with the high-loss, high-permittivity regions. In a series circuit, the properties of the low-capacitance series element (in this case, the constriction) dominate the overall performance. Concomitantly, the capacitance between the metal terminals is reduced. By making the capacitance between the metal terminals small but tunable, a constriction increases the upper limit of the frequency range amenable to ferroelectric tuning. The present patterning concept is expected to be most advantageous for devices and circuits that must operate at frequencies from about 4 to about 60 GHz. A constriction can be designed such that the magnitude of the microwave electric field and the effective width of the region occupied by the microwave electric field become functions of the applied DC electric field, so that tunability is enhanced. It should even be possible to design the constriction to obtain a specific tuning-versus-voltage profile.

Embryo as an active granular fluid: stress-coordinated cellular constriction chains

NASA Astrophysics Data System (ADS)

Gao, Guo-Jie Jason; Holcomb, Michael C.; Thomas, Jeffrey H.; Blawzdziewicz, Jerzy

2016-10-01

Mechanical stress plays an intricate role in gene expression in individual cells and sculpting of developing tissues. However, systematic methods of studying how mechanical stress and feedback help to harmonize cellular activities within a tissue have yet to be developed. Motivated by our observation of the cellular constriction chains (CCCs) during the initial phase of ventral furrow formation in the Drosophila melanogaster embryo, we propose an active granular fluid (AGF) model that provides valuable insights into cellular coordination in the apical constriction process. In our model, cells are treated as circular particles connected by a predefined force network, and they undergo a random constriction process in which the particle constriction probability P is a function of the stress exerted on the particle by its neighbors. We find that when P favors tensile stress, constricted particles tend to form chain-like structures. In contrast, constricted particles tend to form compact clusters when P favors compression. A remarkable similarity of constricted-particle chains and CCCs observed in vivo provides indirect evidence that tensile-stress feedback coordinates the apical constriction activity. Our particle-based AGF model will be useful in analyzing mechanical feedback effects in a wide variety of morphogenesis and organogenesis phenomena.

Physical fitness and associations with anthropometric measurements in 7 to 15-year-old school children.

PubMed

Andreasi, Viviane; Michelin, Edilaine; Rinaldi, Ana Elisa M; Burini, Roberto Carlos

2010-01-01

To analyze associations between health-related physical fitness and the anthropometric and demographic indicators of children at three elementary schools in Botucatu, SP, Brazil. The sample for this cross-sectional study was 988 elementary school students, recruited from the second to ninth grades (an age range of 7 to 15 years). The children underwent anthropometric assessment (weight, height, waist circumference and tricipital and subscapular skin folds) and were tested for health-related physical fitness (flexibility: sit and reach test; abdominal strength/stamina: 1-minute abdominal test; and aerobic stamina: 9-minute running/walking test). Data were analyzed using descriptive statistics plus Student's t test, the chi-square test or Fisher's exact test and logistic regression with a significance level of 5%. The physical fitness levels observed were significantly influenced by age (all levels), sex (abdominal strength/stamina), obesity (all levels), body adiposity (flexibility, abdominal strength/stamina) and abdominal adiposity (abdominal strength/stamina and aerobic stamina). Females were more prone to be unfit in abdominal strength/stamina. Both obesity and excessive abdominal adiposity predisposed children to be unfit in abdominal strength/stamina and aerobic stamina. Excess body adiposity increased the likelihood of poor trunk flexibility. Unhealthy physical fitness levels were related to female sex, obesity and excessive abdominal adiposity. Implementing programs designed to effect lifestyle changes to achieve physical fitness and healthy nutrition in these schools would meet the objectives of promoting healthy body weight and increased physical fitness among these schoolchildren.

Mechanical roles of apical constriction, cell elongation, and cell migration during neural tube formation in Xenopus.

PubMed

Inoue, Yasuhiro; Suzuki, Makoto; Watanabe, Tadashi; Yasue, Naoko; Tateo, Itsuki; Adachi, Taiji; Ueno, Naoto

2016-12-01

Neural tube closure is an important and necessary process during the development of the central nervous system. The formation of the neural tube structure from a flat sheet of neural epithelium requires several cell morphogenetic events and tissue dynamics to account for the mechanics of tissue deformation. Cell elongation changes cuboidal cells into columnar cells, and apical constriction then causes them to adopt apically narrow, wedge-like shapes. In addition, the neural plate in Xenopus is stratified, and the non-neural cells in the deep layer (deep cells) pull the overlying superficial cells, eventually bringing the two layers of cells to the midline. Thus, neural tube closure appears to be a complex event in which these three physical events are considered to play key mechanical roles. To test whether these three physical events are mechanically sufficient to drive neural tube formation, we employed a three-dimensional vertex model and used it to simulate the process of neural tube closure. The results suggest that apical constriction cued the bending of the neural plate by pursing the circumference of the apical surface of the neural cells. Neural cell elongation in concert with apical constriction further narrowed the apical surface of the cells and drove the rapid folding of the neural plate, but was insufficient for complete neural tube closure. Migration of the deep cells provided the additional tissue deformation necessary for closure. To validate the model, apical constriction and cell elongation were inhibited in Xenopus laevis embryos. The resulting cell and tissue shapes resembled the corresponding simulation results.

The king of snakes: performance and morphology of intraguild predators (Lampropeltis) and their prey (Pantherophis).

PubMed

Penning, David A; Moon, Brad R

2017-03-15

Across ecosystems and trophic levels, predators are usually larger than their prey, and when trophic morphology converges, predators typically avoid predation on intraguild competitors unless the prey is notably smaller in size. However, a currently unexplained exception occurs in kingsnakes in the genus Lampropeltis Kingsnakes are able to capture, constrict and consume other snakes that are not only larger than themselves but that are also powerful constrictors (such as ratsnakes in the genus Pantherophis ). Their mechanisms of success as intraguild predators on other constrictors remain unknown. To begin addressing these mechanisms, we studied the scaling of muscle cross-sectional area, pulling force and constriction pressure across the ontogeny of six species of snakes ( Lampropeltis californiae , L. getula , L. holbrooki , Pantherophis alleghaniensis , P. guttatus and P. obsoletus ). Muscle cross-sectional area is an indicator of potential force production, pulling force is an indicator of escape performance, and constriction pressure is a measure of prey-handling performance. Muscle cross-sectional area scaled similarly for all snakes, and there was no significant difference in maximum pulling force among species. However, kingsnakes exerted significantly higher pressures on their prey than ratsnakes. The similar escape performance among species indicates that kingsnakes win in predatory encounters because of their superior constriction performance, not because ratsnakes have inferior escape performance. The superior constriction performance by kingsnakes results from their consistent and distinctive coil posture and perhaps from additional aspects of muscle structure and function that need to be tested in future research. © 2017. Published by The Company of Biologists Ltd.

A spinal thecal sac constriction model supports the theory that induced pressure gradients in the cord cause edema and cyst formation.

PubMed

Josephson, A; Greitz, D; Klason, T; Olson, L; Spenger, C

2001-03-01

Spinal cord cysts are a devastating condition that occur secondary to obstructions of the spinal canal, which may be caused by congenital malformations, trauma, spinal canal stenosis, tumors, meningitis, or arachnoiditis. A hypothesis that could explain how spinal cord cysts form in these situations has been presented recently. Therefore, a novel spinal thecal sac constriction model was implemented to test various aspects of this hypothesis. Thecal sac constriction was achieved by subjecting rats to an extradural silk ligature at the T8 spinal cord level. Rats with complete spinal cord transection served as a second model for comparison. The animals underwent high-resolution magnetic resonance imaging and histological analysis. Thecal sac constriction caused edema cranial and caudal to the ligation within 3 weeks, and cysts developed after 8 to 13 weeks. In contrast, cysts in rats with spinal cord transection were located predominantly in the cranial spinal cord. Histological sections of spinal cords confirmed the magnetic resonance imaging results. Magnetic resonance imaging provided the specific advantage of enabling characterization of events as they occurred repeatedly over time in the spinal cords of individual living animals. The spinal thecal sac constriction model proved useful for investigation of features of the cerebrospinal fluid pulse pressure theory. Edema and cyst distributions were in accordance with this theory. We conclude that induced intramedullary pressure gradients originating from the cerebrospinal fluid pulse pressure may underlie cyst formation in the vicinity of spinal canal obstructions and that cysts are preceded by edema.

The big squeeze: scaling of constriction pressure in two of the world's largest snakes, Python reticulatus and Python molurus bivittatus.

PubMed

Penning, David A; Dartez, Schuyler F; Moon, Brad R

2015-11-01

Snakes are important predators that have radiated throughout many ecosystems, and constriction was important in their radiation. Constrictors immobilize and kill prey by using body loops to exert pressure on their prey. Despite its importance, little is known about constriction performance or its full effects on prey. We studied the scaling of constriction performance in two species of giant pythons (Python reticulatus and Python molurus bivittatus) and propose a new mechanism of prey death by constriction. In both species, peak constriction pressure increased significantly with snake diameter. These and other constrictors can exert pressures dramatically higher than their prey's blood pressure, suggesting that constriction can stop circulatory function and perhaps kill prey rapidly by over-pressurizing the brain and disrupting neural function. We propose the latter 'red-out effect' as another possible mechanism of prey death from constriction. These effects may be important to recognize and treat properly in rare cases when constrictors injure humans. © 2015. Published by The Company of Biologists Ltd.

Cathode-constriction and column-constriction in high current vacuum arcs subjected to an axial magnetic field

NASA Astrophysics Data System (ADS)

Zhang, Zaiqin; Ma, Hui; Liu, Zhiyuan; Geng, Yingsan; Wang, Jianhua

2018-04-01

The influence of the applied axial magnetic field on the current density distribution in the arc column and electrodes is intensively studied. However, the previous results only provide a qualitative explanation, which cannot quantitatively explain a recent experimental data on anode current density. The objective of this paper is to quantitatively determine the current constriction subjected to an axial magnetic field in high-current vacuum arcs according to the recent experimental data. A magnetohydrodynamic model is adopted to describe the high current vacuum arcs. The vacuum arc is in a diffuse arc mode with an arc current ranged from 6 kArms to 14 kArms and an axial magnetic field ranged from 20 mT to 110 mT. By a comparison of the recent experimental work of current density distribution on the anode, the modelling results show that there are two types of current constriction. On one hand, the current on the cathode shows a constriction, and this constriction is termed as the cathode-constriction. On the other hand, the current constricts in the arc column region, and this constriction is termed as the column-constriction. The cathode boundary is of vital importance in a quantitative model. An improved cathode constriction boundary is proposed. Under the improved boundary, the simulation results are in good agreement with the recent experimental data on the anode current density distribution. It is demonstrated that the current density distribution at the anode is sensitive to that at the cathode, so that measurements of the anode current density can be used, in combination with the vacuum arc model, to infer the cathode current density distribution.

Selective kappa-opioid agonists: synthesis and structure-activity relationships of piperidines incorporating on oxo-containing acyl group.

PubMed

Giardina, G; Clarke, G D; Dondio, G; Petrone, G; Sbacchi, M; Vecchietti, V

1994-10-14

This study describes the synthesis and the structure-activity relationships (SARs) of the (S)-(-)-enantiomers of a novel class of 2-(aminomethyl)piperidine derivatives, using kappa-opioid binding affinity and antinociceptive potency as the indices of biological activity. Compounds incorporating the 1-tetralon-6-ylacetyl residue (30 and 34-45) demonstrated an in vivo antinociceptive activity greater than predicted on the basis of their kappa-binding affinities. In particular, (2S)-2-[(dimethylamino)methyl]-1-[(5,6,7,8-tetrahydro-5-oxo-2- naphthyl)acetyl]piperidine (34) was found to have a potency similar to spiradoline in animal models of antinociception after subcutaneous administration, with ED50s of 0.47 and 0.73 mumol/kg in the mouse and in the rat abdominal constriction tests, respectively. Further in vivo studies in mice and/or rats revealed that compound 34, compared to other selective kappa-agonists, has a reduced propensity to cause a number of kappa-related side effects, including locomotor impairment/sedation and diuresis, at antinociceptive doses. For example, it has an ED50 of 26.5 mumol/kg sc in the rat rotarod model, exhibiting a ratio of locomotor impairment/sedation vs analgesia of 36. Possible reasons for this differential activity and its clinical consequence are discussed.

Increasing the availability of l-arginine and nitric oxide increases sensitivity of nitrous oxide (N2O)-insensitive inbred mice to N2O-induced antinociception.

PubMed

Chung, Eunhee; Ohgami, Yusuke; Quock, Raymond M

2016-07-01

Nitrous oxide (N2O)-induced antinociception in mice is dependent on the neuromodulator nitric oxide (NO). In contrast to C57BL/6J (B6) mice, DBA/2J (D2) mice fail to respond to N2O with a robust antinociceptive response or with an increase in brain nitric oxide synthase (NOS) enzyme activity, suggesting that failure of D2 mice to respond to N2O might result from a deficit of NO function. Therefore, it was of interest to determine whether increasing the availability of NO might increase sensitivity of D2 mice to N2O. Male D2 mice were pretreated with sub-antinociceptive intracerebroventricular doses of the NO donor 3-morpholinosydnoimine or the NO precursor l-arginine then assessed for responsiveness to N2O-induced antinociception using the acetic acid abdominal constriction test. Both pretreatments increased the antinociceptive responsiveness of D2 mice to N2O. These results indicate that the NOS enzyme in D2 mice is functional and that the deficit in NO function that obstructs sensitivity to N2O-induced antinociception may lie in availability or utilization of l-arginine. Copyright © 2016 Elsevier Inc. All rights reserved.

In vivo analgesic and anti-inflammatory activities of ursolic acid and oleanoic acid from Miconia albicans (Melastomataceae).

PubMed

Vasconcelos, Maria Anita L; Royo, Vanessa A; Ferreira, Daniele S; Crotti, Antonio E Miller; Andrade e Silva, Márcio L; Carvalho, José Carlos T; Bastos, Jairo Kenupp; Cunha, Wilson R

2006-01-01

The aim of this work was to use in vivo models to evaluate the analgesic and anti-inflammatory activities of ursolic acid (UA) and oleanoic acid (OA), the major compounds isolated as an isomeric mixture from the crude methylene chloride extract of Miconia albicans aerial parts in an attempt to clarify if these compounds are responsible for the analgesic properties displayed by this plant. Ursolic acid inhibited abdominal constriction in a dose-dependent manner, and the result obtained at a content of 40 mg kg(-1) was similar to that produced by administration of acetylsalicylic acid at a content of 100 mg kg(-1). Both acids reduced the number of paw licks in the second phase of the formalin test, and both of them displayed a significant anti-inflammatory effect at a content of 40 mg kg(-1). It is noteworthy that the administration of the isolated mixture, containing 65% ursolic acid/35% oleanolic acid, did not display significant analgesic and anti-inflammatory activities. On the basis of the obtained results, considering that the mixture of UA and OA was poorly active, it is suggested that other compounds, rather than UA and OA, should be responsible for the evaluated activities in the crude extract, since the crude extract samples displayed good activities.

Anti-inflammatory, analgesic and ulcerogenic properties of S-(+)-ibuproxam, racemic ibuproxam-beta-cyclodextrin and S-(+)-ibuproxam-beta-cyclodextrin.

PubMed

Bole-Vunduk, B; Verhnjak, K; Zmitek, J

1996-11-01

The anti-inflammatory, analgesic and gastric mucosal damage-inducing activities of S-(+)-ibuproxam, and S-(+)-ibuproxam-beta-cyclodextrin, new propionic acid derivatives, and racemic ibuproxam-beta-cyclodextrin were investigated in three animal models and compared with those of racemic ibuproxam, racemic ibuprofen and its optical enantiomer S-(+)-ibuprofen. The anti-inflammatory activities of racemic ibuprofen, S-(+)-ibuprofen and racemic ibuproxam in carrageenan-induced paw oedema in rats were almost equipotent and slightly greater than those of S-(+)-ibuproxam and S-(+)-ibuproxam-beta-cyclodextrin, and significantly greater than that of racemic ibuproxam-beta-cyclodextrin. In abdominal constriction tests in mice, the analgesic effects of racemic ibuproxam, S-(+)-ibuproxam, racemic ibuproxam-beta-cyclodextrin and S-(+)-ibuproxam-beta-cyclodextrin were significantly less pronounced than those of racemic ibuprofen and S-(+)-ibuprofen. Ulcerogenic activity of S-(+)-ibuproxam-beta-cyclodextrin in rats was found to be significantly weaker than that of racemic ibuproxam-beta-cyclodextrin, racemic ibuproxam and S-(+)-ibuproxam and, most notably, weaker than those of racemic ibuprofen and S-(+)ibuprofen. These results indicate that S-(+)-ibuproxam-beta-cyclodextrin could be a novel potent anti-inflammatory and analgesic agent with a therapeutic index more favourable than that of the classical non-steroid anti-inflammatory drugs ibuprofen and ibuproxam.

A comparative study on the antinociceptive and anti-inflammatory activities of five Juniperus taxa.

PubMed

Akkol, Esra Küpeli; Güvenç, Ayşegül; Yesilada, Erdem

2009-09-07

Juniperus L. (Cupressaceae) species have been used to various inflammatory and infectious diseases such as bronchitis, colds, cough, fungal infections, hemorrhoids, gynecological diseases, and wounds in Turkish folk medicine. To evaluate this traditional information, anti-inflammatory and antinociceptive activities of the methanolic and aqueous extracts prepared from different parts (stem, fruit and leaves) of the five Turkish taxa under Juniperus section of the gender; J. drupacea, J. communis var. communis, J. communis var. saxatilis, J. oxycedrus subsp. oxycedrus, and J. oxycedrus subsp. macrocarpa growing were investigated. For the anti-inflammatory activity, carrageenan-induced and PGE(2)-induced hind paw edema models, and for the antinociceptive activity p-benzoquinone-induced writhing and hot plate tests in mice were employed. The methanolic extracts of fruit and leaves from J. oxycedrus subsp. oxycedrus and J. communis var. saxatilis exhibited notable inhibition in carrageenan-induced edema model at a dose of 100mg/kg. The same extracts also displayed significant activity against PGE(2)-induced edema model. While, the remaining extracts were found inactive against these edema models. A similar activity pattern was observed against p-benzoquinone-induced abdominal constriction test without inducing any gastric damage or apparent acute toxicity, whereas all extracts were inactive in hot plate test. The experimental data demonstrated that J. oxycedrus subsp. oxycedrus and J. communis var. saxatilis displayed remarkable anti-inflammatory and antinociceptive activities; however, further studies are warranted to define and isolate the active anti-inflammatory and antinociceptive components from these active species which may yield safe and effective agents to be used in the treatment of inflammatory disorders.

Snake constriction rapidly induces circulatory arrest in rats.

PubMed

Boback, Scott M; McCann, Katelyn J; Wood, Kevin A; McNeal, Patrick M; Blankenship, Emmett L; Zwemer, Charles F

2015-07-01

As legless predators, snakes are unique in their ability to immobilize and kill their prey through the process of constriction, and yet how this pressure incapacitates and ultimately kills the prey remains unknown. In this study, we examined the cardiovascular function of anesthetized rats before, during and after being constricted by boas (Boa constrictor) to examine the effect of constriction on the prey's circulatory function. The results demonstrate that within 6 s of being constricted, peripheral arterial blood pressure (PBP) at the femoral artery dropped to 1/2 of baseline values while central venous pressure (CVP) increased 6-fold from baseline during the same time. Electrocardiographic recordings from the anesthetized rat's heart revealed profound bradycardia as heart rate (fH) dropped to nearly half of baseline within 60 s of being constricted, and QRS duration nearly doubled over the same time period. By the end of constriction (mean 6.5±1 min), rat PBP dropped 2.9-fold, fH dropped 3.9-fold, systemic perfusion pressure (SPP=PBP-CVP) dropped 5.7-fold, and 91% of rats (10 of 11) had evidence of cardiac electrical dysfunction. Blood drawn immediately after constriction revealed that, relative to baseline, rats were hyperkalemic (serum potassium levels nearly doubled) and acidotic (blood pH dropped from 7.4 to 7.0). These results are the first to document the physiological response of prey to constriction and support the hypothesis that snake constriction induces rapid prey death due to circulatory arrest. © 2015. Published by The Company of Biologists Ltd.

A simplified method for correcting Tanzer's group II constricted ears: Construction of the superior crus as a strut with cartilage expansion grafting.

PubMed

Kim, Young Soo; Chung, Seum

2016-04-01

A constricted ear, also known as a cup ear or lop ear, is a deformity characterized by curling of the upper portion of the ear, including the helix, scapha, and antihelix. In Tanzer's classification, group II constricted ears have deformities involving the helix and the scapha. Although partial or total absence of the superior crus of the antihelix has been noted in group II constricted ears, most plastic surgeons have corrected group II constricted ears using the expansion technique and skin flaps, without formation of the superior crus. However, the expansion technique does not always yield satisfactory results in group II constricted ears. Between May 2011 and April 2014, the authors operated on 21 patients with group II constricted ears using the technique described in this study. The follow-up period ranged from 2 months to 2 years. In our procedure for correcting group II constricted ears, we focused on restoring the superior crus of the antihelix. As a strong superior crus acts as a strut in the upper third of the ear, it supports the helical rim and creates the scapha. Eventually, the newly formed superior crus enables the helical rim to expand in the upper third of the constricted ear. In this article, we present our method of correcting group II constricted ears, in which the superior crus is constructed as a strut and cartilage expansion grafts are used. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Methanol extract of Xanthium strumarium L. possesses anti-inflammatory and anti-nociceptive activities.

PubMed

Kim, In-Tae; Park, Young-Mi; Won, Jong-Heon; Jung, Hyun-Ju; Park, Hee-Juhn; Choi, Jong-Won; Lee, Kyung-Tae

2005-01-01

As an attempt to identify bioactive natural products with anti-inflammatory activity, we evaluated the effects of the methanol extract of the semen of Xanthium strumarium L. (MEXS) on lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2) and tumor necrosis factor-alpha (TNF-alpha) production in RAW 264.7 cells. Our data indicate that MEXS is a potent inhibitor of NO, PGE2 and TNF-alpha production. Consistent with these findings, the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and iNOS, COX-2 and TNF-alpha mRNA were down-regulated in a concentration-dependent manner. Furthermore, MEXS inhibited nuclear factor kappa B (NF-kappaB) DNA binding activity and the translocation of NF-kappaB to the nucleus by blocking the degradation of inhibitor of kappa B-alpha (IkappaB-alpha). We further evaluated the anti-inflammatory and anti-nociceptive activities of MEXS in vivo. MEXS (100, 200 mg/kg/d, p.o.) reduced acute paw edema induced by carrageenin in rats, and showed analgesic activities in an acetic acid-induced abdominal constriction test and a hot plate test in mice. Thus, our study suggests that the inhibitions of iNOS, COX-2 expression, and TNF-alpha release by the methanol extract of the semen of Xanthium strumarium L. are achieved by blocking NF-kappaB activation, and that this is also responsible for its anti-inflammatory effects.

Piracetam and aniracetam antagonism of centrally active drug-induced antinociception.

PubMed

Galeotti, N; Ghelardini, C; Bartolini, A

1996-04-01

The effects of the nootropic drugs piracetam and aniracetam on antinociception induced by baclofen, bicuculline, and picrotoxin and on baclofen-induced muscle relaxation were studied in mice. Antinociception was investigated using both the hot plate (thermal stimulus) and abdominal constriction (chemical stimulus) tests. Both behaviour inhibition and muscle relaxation were observed by using the rota-rod test. Piracetam (30 mg/kg, IP) and aniracetam (10 mg/kg, PO) reduced baclofen, bicuculline, and picrotoxin antinociception without modifying analgesia induced by non-GABAergic drugs such as morphine, physostigmine, clomipramine, and diphenhydramine. In this concentration range, piracetam, and aniracetam were also able to reduce the inhibition of rota-rod performance. At higher doses piracetam (100 mg/kg, IP) and aniracetam (100 mg/kg, PO) were able to completely prevent baclofen antinociception. However, when prevention of GABAergic antinociception was complete, piracetam and aniracetam were able to block non-GABAergic antinociception also. comparing the effects of piracetam and aniracetam with those exerted by the GABAB antagonist CGP 35348, a reduction of non-GABAergic analgesia was also observed using higher doses of CGP 35348 (2.5 micrograms per mouse ICV). The present results indicate that piracetam and aniracetam, by preventing both of the investigated effects of baclofen, have some selectivity against GABAB-mediated inhibition. The well-known activity of piracetam and aniracetam on learning and memory might, therefore, depend, at least in part, on the removal of inhibitory GABAB mechanisms that impair attention and cognitive functions.

A pressure-gradient mechanism for vortex shedding in constricted channels

PubMed Central

Boghosian, M. E.; Cassel, K. W.

2013-01-01

Numerical simulations of the unsteady, two-dimensional, incompressible Navier–Stokes equations are performed for a Newtonian fluid in a channel having a symmetric constriction modeled by a two-parameter Gaussian distribution on both channel walls. The Reynolds number based on inlet half-channel height and mean inlet velocity ranges from 1 to 3000. Constriction ratios based on the half-channel height of 0.25, 0.5, and 0.75 are considered. The results show that both the Reynolds number and constriction geometry have a significant effect on the behavior of the post-constriction flow field. The Navier–Stokes solutions are observed to experience a number of bifurcations: steady attached flow, steady separated flow (symmetric and asymmetric), and unsteady vortex shedding downstream of the constriction depending on the Reynolds number and constriction ratio. A sequence of events is described showing how a sustained spatially growing flow instability, reminiscent of a convective instability, leads to the vortex shedding phenomenon via a proposed streamwise pressure-gradient mechanism. PMID:24399860

Constrictive Pericarditis 5 Months after Radiation Therapy in a 62-Year-Old Woman with Esophageal Cancer.

PubMed

Yeneneh, Beeletsega T; Allen, Sorcha; Panse, Prasad; Mookadam, Farouk; Rule, William

2017-12-01

Most pericardial changes appear within a few weeks in patients who have undergone radiation therapy for thoracic neoplasms. Chronic pericardial constriction typically occurs decades later, consequent to fibrosis. Early constrictive pericarditis after chest irradiation is quite rare. We report the case of a 62-year-old woman who underwent radiation therapy for esophageal cancer and presented with constrictive pericarditis 5 months later. We searched the English-language medical literature from January 1986 through December 2015 for reports of early constrictive pericarditis after irradiation for thoracic malignancies. We defined "early" as a diagnosis within one year after radiation therapy. Five cases fit our criteria, and we summarize the findings here. To our knowledge, ours is the first definitive report of a patient with esophageal cancer to present with early radiation-induced constrictive pericarditis. We conclude that constrictive pericarditis can occur early after radiation for thoracic malignancies, albeit rarely. When planning care for cancer patients, awareness of this sequela is helpful.

Gas arc constriction for plasma arc welding

NASA Technical Reports Server (NTRS)

McGee, William F. (Inventor); Rybicki, Daniel J. (Inventor)

1994-01-01

A welding torch for plasma arc welding apparatus has an inert gas applied circumferentially about the arc column externally of the constricting nozzle so as to apply a constricting force on the arc after it has exited the nozzle orifice and downstream of the auxiliary shielding gas. The constricting inert gas is supplied to a plenum chamber about the body of the torch and exits through a series of circumferentially disposed orifices in an annular wall forming a closure at the forward end of the constricting gas plenum chamber. The constricting force of the circumferential gas flow about the arc concentrates and focuses the arc column into a more narrow and dense column of energy after exiting the nozzle orifice so that the arc better retains its energy density prior to contacting the workpiece.

Significance of fibrotic bands in utero--Amniotic band sequence with limb body wall complex: A rare case of fetal autopsy.

PubMed

Devi, P Lekshmi; Cicy, P J; Thambi, Renu; Poothiode, Usha

2015-01-01

Amniotic band sequence (ABS) includes a wide spectrum of abnormalities resulting from entrapment of various fetal parts from a disrupted amnion, ranging from a mere constriction ring affecting a finger to a fatal form called limb body wall complex (LBWC). Reported cases of ABS with LBWC are very few. The spectrum of anomalies depends on which part gets entrapped and at what point of gestation. Hence, the clinical presentation can be extremely variable. Early detection of such cases using sonology is really challenging due to the small size of the fibrotic bands. Here, we present a case of amniotic band syndrome with LBWC in a fetus at 24 weeks of gestation, which was referred for an autopsy. The fetus also showed scoliosis, gastroschisis, lumbosacral meningocele, congenital talipes equinovarus, and cleft palate, thus having features of placenta cranial and placenta abdominal phenotype which is very rare.

The effects of normal and therapeutic baths on the central vascular organs of persons with healthy hearts, as measured by X-ray

NASA Technical Reports Server (NTRS)

Boehm, G.; Ekert, FR.

1988-01-01

According to current information, baths have a four-fold effect on the circulation: (1) Dilation or constriction is produced in the area of the blood vessels in the skin as a result of thermal, chemical or mechanical stimuli; (2) This reaction in the dermal vascular system produces a further effect on the central vessels in the extremities, the area of the splanchnicus, and other body cavities; (3) The reflect transposition of other organ systems, i.e., the respiratory organs, has a reaction on the circulation; and (4) The water pressure of the bath has a hydrostatic effect, i.e., on the one hand it empties peripheral veins more rapidly, and on the other it increases the intra-abdominal pressure and this reduces once again the circulation in the area of the splanchnicus.

Widespread pain reliever profile of a flower extract of Tanacetum parthenium.

PubMed

Di Cesare Mannelli, Lorenzo; Tenci, Barbara; Zanardelli, Matteo; Maidecchi, Anna; Lugli, Andrea; Mattoli, Luisa; Ghelardini, Carla

2015-07-15

Tanacetum parthenium L., commonly called Feverfew, is known for anti-inflammatory and anti-migraine properties. Aimed to individuate new therapeutical strategies to control acute and persistent pain induced by different origins we tested two hydroalcoholic extracts obtained from Feverfew flowers and leaves, respectively. Extracts were characterized according to the European Pharmacopoeia monograph. Both the extracts were tested after acute per os administration in the dose range 30-1000 mg kg(-1). The anti-nociceptive properties were evaluated by the Writhing test in mice. The number of abdominal contractions was dose dependently reduced by the flower extract. It reduced mechanical hypersensitivity (Paw pressure test) related to the acute inflammatory phase induced by carrageenan similarly to diclofenac and ibuprofen. In the osteoarthritis model induced by intra articular injection of monoiodoacetate (MIA) the flower extract significantly increased the pain threshold peaking 30 min after treatment. Moreover, it was effective in the chronic constriction injury model of neuropathic pain showing activity similar to the anti-epileptic drug gabapentin. The flower extract activity was confirmed in rat models of chemotherapy-induced neuropathic pain. The mechanical hypersensitivity induced by repeated treatments with the anticancer drug oxaliplatin and with the antiviral dideoxycytidine was significantly reduced after a single injection of Feverfew flower extract. The leaf extract showed lesser efficacy and potency and it was devoid of any effect in carrageenan-, MIA- and chemotherapy-induced pain. The present Feverfew flower extract behaves as a potent pain reliever in acute, inflammatory, articular and neuropathic pain. It appears as a natural strategy potentially suitable for the treatment of different kinds of pain. Copyright © 2015 Elsevier GmbH. All rights reserved.

Modeling the acoustics of American English /r/ using configurable articulatory synthesis (CASY)

NASA Astrophysics Data System (ADS)

Lehnert-Lehouillier, Heike; Iskarous, Khalil; Whalen, Douglas H.

2004-05-01

The claim that articulatory variation in /r/ production exhibits systematic tradeoffs to achieve a stable acoustic signal (Guenther et al., 1999) was tested using configurable articulatory synthesis (CASY) and ultrasound data. In particular, the hypothesis was tested that multiple constrictions during /r/ production are necessary to achieve a low enough F3. Ultrasound and Optotrak data from four speakers pronouncing /r/ in different vocalic contexts were used to determine where in the vocal tract the tongue gestures are placed. This data was then modeled using CASY parameters and was used to determine how the three gestures in /r/ (labial, palatal, and pharyngeal) contribute to the F3 value observed in the speech signal simultaneously recorded with the ultrasound. This was done by varying the degree and location of the lingual constrictions and the degree of the labial constriction and determining the effect on F3. It was determined that the three gestures in /r/ contribute in differing amounts to the overall F3 lowering. Furthermore, it does not seem that all three gestures are necessary for F3 lowering. This lends support to the hypothesis that the goal in /r/ production is the simultaneous achievement of three gestures. [Work supported by NIH Grant DC-02717.

Modeling the Mechanics of Cell Division: Influence of Spontaneous Membrane Curvature, Surface Tension, and Osmotic Pressure

PubMed Central

Beltrán-Heredia, Elena; Almendro-Vedia, Víctor G.; Monroy, Francisco; Cao, Francisco J.

2017-01-01

Many cell division processes have been conserved throughout evolution and are being revealed by studies on model organisms such as bacteria, yeasts, and protozoa. Cellular membrane constriction is one of these processes, observed almost universally during cell division. It happens similarly in all organisms through a mechanical pathway synchronized with the sequence of cytokinetic events in the cell interior. Arguably, such a mechanical process is mastered by the coordinated action of a constriction machinery fueled by biochemical energy in conjunction with the passive mechanics of the cellular membrane. Independently of the details of the constriction engine, the membrane component responds against deformation by minimizing the elastic energy at every constriction state following a pathway still unknown. In this paper, we address a theoretical study of the mechanics of membrane constriction in a simplified model that describes a homogeneous membrane vesicle in the regime where mechanical work due to osmotic pressure, surface tension, and bending energy are comparable. We develop a general method to find approximate analytical expressions for the main descriptors of a symmetrically constricted vesicle. Analytical solutions are obtained by combining a perturbative expansion for small deformations with a variational approach that was previously demonstrated valid at the reference state of an initially spherical vesicle at isotonic conditions. The analytic approximate results are compared with the exact solution obtained from numerical computations, getting a good agreement for all the computed quantities (energy, area, volume, constriction force). We analyze the effects of the spontaneous curvature, the surface tension and the osmotic pressure in these quantities, focusing especially on the constriction force. The more favorable conditions for vesicle constriction are determined, obtaining that smaller constriction forces are required for positive spontaneous curvatures, low or negative membrane tension and hypertonic media. Conditions for spontaneous constriction at a given constriction force are also determined. The implications of these results for biological cell division are discussed. This work contributes to a better quantitative understanding of the mechanical pathway of cellular division, and could assist the design of artificial divisomes in vesicle-based self-actuated microsystems obtained from synthetic biology approaches. PMID:28579960

Roles of oxygen radicals and elastase in citric acid-induced airway constriction of guinea-pigs

PubMed Central

Lai, Y -L; Chiou, W -Y; Lu, F J; Chiang, L Y

1999-01-01

Antioxidants attenuate noncholinergic airway constriction. To further investigate the relationship between tachykinin-mediated airway constriction and oxygen radicals, we explored citric acid-induced bronchial constriction in 48 young Hartley strain guinea-pigs, divided into six groups: control; citric acid; hexa(sulphobutyl)fullerenes+citric acid; hexa(sulphobutyl)fullerenes+phosphoramidon+citric acid; dimethylthiourea (DMTU)+citric acid; and DMTU+phosphoramidon+citric acid. Hexa(sulphobutyl)fullerenes and DMTU are scavengers of oxygen radicals while phosphoramidon is an inhibitor of the major degradation enzyme for tachykinins. Animals were anaesthetized, paralyzed, and artificially ventilated. Each animal was given 50 breaths of 4 ml saline or citric acid aerosol. We measured dynamic respiratory compliance (Crs), forced expiratory volume in 0.1 (FEV0.1), and maximal expiratory flow at 30% total lung capacity (V[dot above]max30) to evaluate the degree of airway constriction. Citric acid, but not saline, aerosol inhalation caused marked decreases in Crs, FEV0.1 and V[dot above]max30, indicating marked airway constriction. This constriction was significantly attenuated by either hexa(sulphobutyl)fullerenes or by DMTU. In addition, phosphoramidon significantly reversed the attenuating action of hexa(sulphobutyl)fullerenes, but not that of DMTU. Citric acid aerosol inhalation caused increases in both lucigenin- and t-butyl hydroperoxide-initiated chemiluminescence counts, indicating citric acid-induced increase in oxygen radicals and decrease in antioxidants in bronchoalveolar lavage fluid. These alterations were significantly suppressed by either hexa(sulphobutyl)fullerenes or DMTU. An elastase inhibitor eglin-c also significantly attenuated citric acid-induced airway constriction, indicating the contributing role of elastase in this type of constriction. We conclude that both oxygen radicals and elastase play an important role in tachykinin-mediated, citric acid-induced airway constriction. PMID:10188991

Use of Cardiac Magnetic Resonance Imaging Based Measurements of Inferior Vena Cava Cross-Sectional Area in the Diagnosis of Pericardial Constriction.

PubMed

Hanneman, Kate; Thavendiranathan, Paaladinesh; Nguyen, Elsie T; Moshonov, Hadas; Wald, Rachel; Connelly, Kim A; Paul, Narinder S; Wintersperger, Bernd J; Crean, Andrew M

2015-08-01

To evaluate the value of cardiac magnetic resonance imaging (MRI)-based measurements of inferior vena cava (IVC) cross-sectional area in the diagnosis of pericardial constriction. Patients who had undergone cardiac MRI for evaluation of clinically suspected pericardial constriction were identified retrospectively. The diagnosis of pericardial constriction was established by clinical history, echocardiography, cardiac catheterization, intraoperative findings, and/or histopathology. Cross-sectional areas of the suprahepatic IVC and descending aorta were measured on a single axial steady-state free-precession (SSFP) image at the level of the esophageal hiatus in end-systole. Logistic regression and receiver-operating curve (ROC) analyses were performed. Thirty-six patients were included; 50% (n = 18) had pericardial constriction. Mean age was 53.9 ± 15.3 years, and 72% (n = 26) were male. IVC area, ratio of IVC to aortic area, pericardial thickness, and presence of respirophasic septal shift were all significantly different between patients with constriction and those without (P < .001 for all). IVC to aortic area ratio had the highest odds ratio for the prediction of constriction (1070, 95% confidence interval [8.0-143051], P = .005). ROC analysis illustrated that IVC to aortic area ratio discriminated between those with and without constriction with an area under the curve of 0.96 (95% confidence interval [0.91-1.00]). In patients referred for cardiac MRI assessment of suspected pericardial constriction, measurement of suprahepatic IVC cross-sectional area may be useful in confirming the diagnosis of constriction when used in combination with other imaging findings, including pericardial thickness and respirophasic septal shift. Copyright © 2015 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Bacopa monnieri: An evaluation of antihyperglycemic and antinociceptive potential of methanolic extract of whole plants.

PubMed

Taznin, Inin; Mukti, Mohsina; Rahmatullah, Mohammed

2015-11-01

Antihyperglycemic and antinociceptive activity studies were carried out with methanolic extract of whole plants of Bacopa monnieri, respectively, through oral glucose tolerance test and gastric pain model induced by acetic acid in Swiss albino mice. In OGTT (oral glucose tolerance tests) conducted with glucose-challenged mice, the extract, administered at four doses of 50, 100, 200 and 400mg per kg body weight, dose-dependently and significantly inhibited the increase in serum glucose concentrations, respectively, by 33.3, 34.2, 42.1 and 44.2%. A standard antihyperglycemic drug, glibenclamide, when administered at a dose of 10mg per kg body weight, inhibited increase in serum glucose concentration by 50.7%. From the results, it can be concluded that the methanolic extract of the plant possess significant antihyperglycemic potential. In antinociceptive activity tests, administration of the extract at the aforementioned four doses also significantly and dose-dependently reduced the number of acetic acid-induced gastric constrictions in mice. The percent inhibitions in gastric constrictions were, respectively, 43.4, 46.6, 50.0, and 53.4 at the above four doses. A reference antinociceptive drug, aspirin, when administered at a dose of 200 mg per kg body weight, reduced the number of gastric constrictions by 40.0%. Thus the extract at even the lowest dose of 50 mg, demonstrated antinociceptive activity better than that of aspirin, and which activity was much more than aspirin at the other three higher doses tested. The results demonstrate that the plant can be an excellent candidate for further studies towards isolation of antihyperglycemic and pain-killing compounds.

Chronic abdominal wall pain--a diagnostic challenge for the surgeon.

PubMed

Lindsetmo, Rolv-Ole; Stulberg, Jonah

2009-07-01

Chronic abdominal wall pain (CAWP) occurs in about 30% of all patients presenting with chronic abdominal pain. The authors review the literature identified in a PubMed search regarding the abdominal wall as the origin of chronic abdominal pain. CAWP is frequently misinterpreted as visceral or functional abdominal pain. Misdiagnosis often leads to a variety of investigational procedures and even abdominal operations with negative results. With a simple clinical test (Carnett's test), >90% of patients with CAWP can be recognized, without risk for missing intra-abdominal pathology. The condition can be confirmed when the injection of local anesthetics in the trigger point(s) relieves the pain. A fasciotomy in the anterior abdominal rectus muscle sheath through the nerve foramina of the affected branch of one of the anterior intercostal nerves heals the pain.

Seronegative rheumatoid arthritis: a rare cause of effusive-constrictive pericarditis requiring pericardiectomy.

PubMed

Soo, Alan; Graham, Alastair

2012-04-01

Effusive-constrictive pericarditis is a rare condition. In this report, we describe a case of effusive-constrictive pericarditis caused by seronegative rheumatoid arthritis which was successfully treated with surgical pericardiectomy.

Vasoconstrictive responses of the testicular and caudal arteries in bulls exposed to ergot alkaloids from tall fescue

USDA-ARS?s Scientific Manuscript database

Color Doppler ultasonography was used to evaluate vasoconstrictive responses of the testicular artery in yearling bulls to ergot alkaloids. Ergot alkaloid-induced constriction of the testicular artery could disrupt thermoregulation of the testes and reduce bull fertility. Luminal areas of the test...

Pump out the volume--The effect of tracheal and subelytral pressure pulses on convective gas exchange in a dung beetle, Circellium bacchus (Fabricus).

PubMed

Duncan, Frances D; Förster, Thomas D; Hetz, Stefan K

2010-05-01

Many flightless beetles like the large apterous dung beetle Circellium bacchus, possess a subelytral cavity (SEC) providing an extra air space below the elytra which connects to the tracheal system (TS) via metathoracic and abdominal spiracles. By measuring subelytral and intratracheal pressure as well as body movements and gas exchange simultaneously in a flow-through setup, we investigated the contribution of convection on Circellium respiratory gas exchange. No constriction phase was observed. TS and SEC pressures were always around atmospheric values. During interburst phase open abdominal spiracles and a leaky SEC led to small CO(2)-peaks on a continuous CO(2) baseline, driven by intermittent positive tracheal pressure peaks in anti-phase with small negative subelytral pressure peaks caused by dorso-ventral tergite action. Spiracle opening was accompanied by two types of body movements. Higher frequency telescoping body movements at the beginning of opening resulted in high amplitude SEC and TS pressure peaks. High frequency tergite movements caused subelytral pressure peaks and led to a saw tooth like CO(2) release pattern in a burst. We propose that during the burst open mesothoracic spiracles increase the compliance of the subelytral cavity allowing big volumes of tracheal air being pulled out by convection. Copyright 2009 Elsevier Ltd. All rights reserved.

[Constricted ear therapy with free auricular composite grafts].

PubMed

Liu, Tun; Zhang, Lian-sheng; Zhuang, Hong-xing; Zhang, Ke-yuan

2004-03-01

A simple and effective therapy for single side constricted ear. Transplanting normal side free composite auricular grafts to constricted ear (15 patients and 15 sides), then lengthening the helix, exposing the scapha, correcting deformity. The 15 patients composite grafts all survived. The helix has been lengthened, the scapha exposed, the normal ear reduced, the constricted ear augmented and two sides ear have become symmetry. This method is simple and results are satisfied.

Fully nonlinear Goertler vortices in constricted channel flows and their effect on the onset of separation

NASA Technical Reports Server (NTRS)

Denier, James P.; Hall, Philip

1992-01-01

The development of fully nonlinear Goertler vortices in high Reynolds number flow in a symmetrically constricted channel is investigated. Attention is restricted to the case of 'strongly' constricted channels considered by Smith and Daniels (1981) for which the scaled constriction height is asymptotically large. Such flows are known to develop a Goldstein singularity and subsequently become separated at some downstream station past the point of maximum channel constriction. It is shown that these flows can support fully nonlinear Goertler vortices, of the form elucidated by Hall and Lakin (1988), for constrictions which have an appreciable region of local concave curvature upstream of the position at which separation occurs. The effect on the onset of separation due to the nonlinear Goertler modes is discussed. A brief discussion of other possible nonlinear states which may also have a dramatic effect in delaying (or promoting) separation is given.

A corkscrew model for dynamin constriction

PubMed Central

Mears, Jason A.; Ray, Pampa; Hinshaw, Jenny E.

2007-01-01

SUMMARY Numerous vesiculation processes throughout the eukaryotic cell are dependant on the protein dynamin, a large GTPase that constricts lipid bilayers. We have combined x-ray crystallography and cryo-electron microscopy (cryo-EM) data to generate a coherent model of dynamin-mediated membrane constriction. X-ray structures of mammalian GTPase and pleckstrin homology (PH) domains of dynamin were fit to cryo-EM structures of human ΔPRD dynamin helices bound to lipid in non-constricted and constricted states. Proteolysis and immunogold labeling experiments confirm the topology of dynamin domains predicted from the helical arrays. Based on the fitting, an observed twisting motion of the GTPase, middle and GTPase-effector domains coincides with conformational changes determined by cryo-EM. We propose a corkscrew model for dynamin constriction based on these motions and predict regions of sequence important for dynamin function as potential targets for future mutagenic and structural studies. PMID:17937909

The role of microtubules in contractile ring function.

PubMed

Conrad, A H; Paulsen, A Q; Conrad, G W

1992-05-01

During cytokinesis, a cortical contractile ring forms around a cell, constricts to a stable tight neck and terminates in separation of the daughter cells. At first cleavage, Ilyanassa obsoleta embryos form two contractile rings simultaneously. The cleavage furrow (CF), in the animal hemisphere between the spindle poles, constricts to a stable tight neck and separates the daughter cells. The third polar lobe constriction (PLC-3), in the vegetal hemisphere below the spindle, constricts to a transient tight neck, but then relaxes, allowing the polar lobe cytoplasm to merge with one daughter cell. Eggs exposed to taxol, a drug that stabilizes microtubules, before the CF or the PLC-3 develop, fail to form CFs, but form stabilized tight PLCs. Eggs exposed to taxol at the time of PLC-3 formation develop varied numbers of constriction rings in their animal hemispheres and one PLC in their vegetal hemisphere, none of which relax. Eggs exposed to taxol after PLC-3 initiation form stabilized tight CFs and PLCs. At maximum constriction, control embryos display immunolocalization of nonextractable alpha-tubulin in their CFs, but not in their PLCs, and reveal, via electron microscopy, many microtubules extending through their CFs, but not through their PLCs. Embryos which form stabilized tightly constricted CFs and PLCs in the presence of taxol display immunolocalization of nonextractable alpha-tubulin in both constrictions and show many polymerized microtubules extending through both CFs and PLCs. These results suggest that the extension of microtubules through a tight contractile ring may be important for stabilizing that constriction and facilitating subsequent cytokinesis.

The role of microtubules in contractile ring function

NASA Technical Reports Server (NTRS)

Conrad, A. H.; Paulsen, A. Q.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)

1992-01-01

During cytokinesis, a cortical contractile ring forms around a cell, constricts to a stable tight neck and terminates in separation of the daughter cells. At first cleavage, Ilyanassa obsoleta embryos form two contractile rings simultaneously. The cleavage furrow (CF), in the animal hemisphere between the spindle poles, constricts to a stable tight neck and separates the daughter cells. The third polar lobe constriction (PLC-3), in the vegetal hemisphere below the spindle, constricts to a transient tight neck, but then relaxes, allowing the polar lobe cytoplasm to merge with one daughter cell. Eggs exposed to taxol, a drug that stabilizes microtubules, before the CF or the PLC-3 develop, fail to form CFs, but form stabilized tight PLCs. Eggs exposed to taxol at the time of PLC-3 formation develop varied numbers of constriction rings in their animal hemispheres and one PLC in their vegetal hemisphere, none of which relax. Eggs exposed to taxol after PLC-3 initiation form stabilized tight CFs and PLCs. At maximum constriction, control embryos display immunolocalization of nonextractable alpha-tubulin in their CFs, but not in their PLCs, and reveal, via electron microscopy, many microtubules extending through their CFs, but not through their PLCs. Embryos which form stabilized tightly constricted CFs and PLCs in the presence of taxol display immunolocalization of nonextractable alpha-tubulin in both constrictions and show many polymerized microtubules extending through both CFs and PLCs. These results suggest that the extension of microtubules through a tight contractile ring may be important for stabilizing that constriction and facilitating subsequent cytokinesis.

Effect of hexylene glycol-altered microtubule distributions on cytokinesis and polar lobe formation in fertilized eggs of Ilyanassa obsoleta

NASA Technical Reports Server (NTRS)

Conrad, A. H.; Stephens, A. P.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)

1994-01-01

Some effects of gravity on early morphogenesis are correlated with microtubule locations within cells. During first cleavage in Ilyanassa obsoleta embryos, a transitory polar lobe constriction forms and then relaxes, allowing the polar lobe to merge with one daughter cell. If the polar lobe is equally divided or removed, morphogenesis is severely disrupted. To examine microtuble locations during early Ilyanassa development, eggs were fixed and stained for polymerized alpha-tubulin during first cleavage. The mitotic apparatus assembles at the animal pole. The cleavage furrow forms between the asters, constricting to a stabilized intercellular bridge encircling midbody-bound microtubules, whereas the polar lobe constriction forms below and parallel to the spindle, constricting to a transitory intercellular bridge encircling no detectable microtubules. At metaphase an alpha-tubulin epitope is distributed throughout the spindle, whereas a beta-tubulin epitope is present predominantly in the asters. Incubation in hexylene glycol, a drug that increases microtubule polymerization, during mitosis causes the polar lobe constriction to tighten around polymerized alpha-tubulin and remain stably constricted. If hexylene glycol is removed, alpha-tubulin staining disappears from the polar lobe constriction, which relaxes, whereas microtubules remain in the cleavage furrow, which remains constricted. These observations suggest that asymmetric distribution of microtubules affects early Ilyanassa cleavage patterns, and that continued presence of microtubules extending through an intercellular bridge is important for stabilization of the bridge constriction prior to completion of cytokinesis. These data provide the basis for further analysis of the role of microtubules in possible microgravity disruptions of Ilyanassa development.

Gender and Racial Disparities in Life-Space Constriction Among Older Adults.

PubMed

Choi, Moon; O'Connor, Melissa L; Mingo, Chivon A; Mezuk, Briana

2016-12-01

"Life-space" is the spatial area through which a person experiences and interacts with the world. Life-space constriction, the shrinking of the spatial area that a person traverses, is associated with negative health outcomes in later life. Racial and gender disparities in mobility as indicated by life-space constriction are thought to contribute to broader disparities in health and functioning among older adults. Data come from the 5-year follow-up of the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) Study (N = 2,765; mean age = 73.6; 75.8% women; 73.7% White). Life-space constriction was defined as "not traveling beyond one's town." A series of logistic regression and Cox proportional hazard models were used to estimate risk for incident life-space constriction by race and gender. Blacks and women had greater likelihood of life-space constriction at baseline. Women were more likely to experience incident life-space constriction at follow-up relative to men (Hazard ratio [HR]: 1.89, 95% Confidence interval [CI]: 1.26-2.83). Blacks were associated with lower risk of life-space constriction over time (HR: 0.67, 95% CI: 0.45-0.99) relative to Whites. Disparities in life-space constriction by gender and race exist in later life. Understanding the processes underlying these mobility restrictions is important to developing intervention programs to enhance health and functioning for older adults. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Nanowire structures and electrical devices

DOEpatents

Bezryadin, Alexey; Remeika, Mikas

2010-07-06

The present invention provides structures and devices comprising conductive segments and conductance constricting segments of a nanowire, such as metallic, superconducting or semiconducting nanowire. The present invention provides structures and devices comprising conductive nanowire segments and conductance constricting nanowire segments having accurately selected phases including crystalline and amorphous states, compositions, morphologies and physical dimensions, including selected cross sectional dimensions, shapes and lengths along the length of a nanowire. Further, the present invention provides methods of processing nanowires capable of patterning a nanowire to form a plurality of conductance constricting segments having selected positions along the length of a nanowire, including conductance constricting segments having reduced cross sectional dimensions and conductance constricting segments comprising one or more insulating materials such as metal oxides.

Superconducting nanoribbon with a constriction: A quantum-confined Josephson junction

NASA Astrophysics Data System (ADS)

Flammia, L.; Zhang, L.-F.; Covaci, L.; Perali, A.; Milošević, M. V.

2018-04-01

Extended defects are known to strongly affect nanoscale superconductors. Here, we report the properties of superconducting nanoribbons with a constriction formed between two adjacent step edges by solving the Bogoliubov-de Gennes equations self-consistently in the regime where quantum confinement is important. Since the quantum resonances of the superconducting gap in the constricted area are different from the rest of the nanoribbon, such constriction forms a quantum-confined S-S'-S Josephson junction, with a broadly tunable performance depending on the length and width of the constriction with respect to the nanoribbon, and possible gating. These findings provide an intriguing approach to further tailor superconducting quantum devices where Josephson effect is of use.

Effects of carvedilol on structural and functional outcomes and plasma biomarkers in the mouse transverse aortic constriction heart failure model.

PubMed

Hampton, Caryn; Rosa, Raymond; Szeto, Daphne; Forrest, Gail; Campbell, Barry; Kennan, Richard; Wang, Shubing; Huang, Chin-Hu; Gichuru, Loise; Ping, Xiaoli; Shen, Xiaolan; Small, Kersten; Madwed, Jeffrey; Lynch, Joseph J

2017-01-01

Despite the widespread use of the mouse transverse aortic constriction heart failure model, there are no reports on the characterization of the standard-of-care agent carvedilol in this model. Left ventricular pressure overload was produced in mice by transverse aortic constriction between the innominate and left common carotid arteries. Carvedilol was administered at multiple dose levels (3, 10 and 30 mg/kg/day per os ; yielding end-study mean plasma concentrations of 0.002, 0.015 and 0.044 µM, respectively) in a therapeutic design protocol with treatment initiated after the manifestation of left ventricular remodeling at 3 weeks post transverse aortic constriction and continued for 10 weeks. Carvedilol treatment in transverse aortic constriction mice significantly decreased heart rate and left ventricular dP/dt (max) at all dose levels consistent with β-adrenoceptor blockade. The middle dose of carvedilol significantly decreased left ventricular weight, whereas the higher dose decreased total heart, left and right ventricular weight and wet lung weight compared to untreated transverse aortic constriction mice. The higher dose of carvedilol significantly increased cardiac performance as measured by ejection fraction and fractional shortening and decreased left ventricular end systolic volume consistent with the beneficial effect on cardiac function. End-study plasma sST-2 and Gal-3 levels did not differ among sham, transverse aortic constriction control and transverse aortic constriction carvedilol groups. Plasma b rain natriuretic peptide concentrations were elevated significantly in transverse aortic constriction control animals (~150%) compared to shams in association with changes in ejection fraction and heart weight and tended to decrease (~30%, p = 0.10-0.12) with the mid- and high-dose carvedilol treatment. A comparison of carvedilol hemodynamic and structural effects in the mouse transverse aortic constriction model versus clinical use indicates a strong agreement in effect profiles preclinical versus clinical, providing important translational validation for this widely used animal model. The present plasma brain natriuretic peptide biomarker findings support the measurement of plasma natriuretic peptides in the mouse transverse aortic constriction model to extend the translational utility of the model.

Effects of carvedilol on structural and functional outcomes and plasma biomarkers in the mouse transverse aortic constriction heart failure model

PubMed Central

Hampton, Caryn; Rosa, Raymond; Szeto, Daphne; Forrest, Gail; Campbell, Barry; Kennan, Richard; Wang, Shubing; Huang, Chin-Hu; Gichuru, Loise; Ping, Xiaoli; Shen, Xiaolan; Small, Kersten; Madwed, Jeffrey; Lynch, Joseph J

2017-01-01

Introduction: Despite the widespread use of the mouse transverse aortic constriction heart failure model, there are no reports on the characterization of the standard-of-care agent carvedilol in this model. Methods: Left ventricular pressure overload was produced in mice by transverse aortic constriction between the innominate and left common carotid arteries. Carvedilol was administered at multiple dose levels (3, 10 and 30 mg/kg/day per os; yielding end-study mean plasma concentrations of 0.002, 0.015 and 0.044 µM, respectively) in a therapeutic design protocol with treatment initiated after the manifestation of left ventricular remodeling at 3 weeks post transverse aortic constriction and continued for 10 weeks. Results: Carvedilol treatment in transverse aortic constriction mice significantly decreased heart rate and left ventricular dP/dt (max) at all dose levels consistent with β-adrenoceptor blockade. The middle dose of carvedilol significantly decreased left ventricular weight, whereas the higher dose decreased total heart, left and right ventricular weight and wet lung weight compared to untreated transverse aortic constriction mice. The higher dose of carvedilol significantly increased cardiac performance as measured by ejection fraction and fractional shortening and decreased left ventricular end systolic volume consistent with the beneficial effect on cardiac function. End-study plasma sST-2 and Gal-3 levels did not differ among sham, transverse aortic constriction control and transverse aortic constriction carvedilol groups. Plasma brain natriuretic peptide concentrations were elevated significantly in transverse aortic constriction control animals (~150%) compared to shams in association with changes in ejection fraction and heart weight and tended to decrease (~30%, p = 0.10–0.12) with the mid- and high-dose carvedilol treatment. Conclusion: A comparison of carvedilol hemodynamic and structural effects in the mouse transverse aortic constriction model versus clinical use indicates a strong agreement in effect profiles preclinical versus clinical, providing important translational validation for this widely used animal model. The present plasma brain natriuretic peptide biomarker findings support the measurement of plasma natriuretic peptides in the mouse transverse aortic constriction model to extend the translational utility of the model. PMID:28491305

­Back-to-back mechanisms drive actomyosin ring closure during Drosophila embryo cleavage

PubMed Central

2016-01-01

Contraction of actomyosin rings during cytokinesis is typically attributed to actin filaments sliding toward each other via Myosin-2 motor activity. However, rings constrict in some cells in the absence of Myosin-2 activity. Thus, ring closure uses Myosin-2–dependent and –independent mechanisms. But what the Myosin-2–independent mechanisms are, and to what extent they are sufficient to drive closure, remains unclear. During cleavage in Drosophila melanogaster embryos, actomyosin rings constrict in two sequential and mechanistically distinct phases. We show that these phases differ in constriction speed and are genetically and pharmacologically separable. Further, Myosin-2 activity is required for slow constriction in “phase 1” but is largely dispensable for fast constriction in “phase 2,” and F-actin disassembly is only required for fast constriction in phase 2. Switching from phase 1 to phase 2 seemingly relies on the spatial organization of F-actin as controlled by Cofilin, Anillin, and Septin. Our work shows that fly embryos present a singular opportunity to compare separable ring constriction mechanisms, with varying Myosin-2 dependencies, in one cell type and in vivo. PMID:27799369

[A commonly seen cause of abdominal pain: abdominal cutaneous nerve entrapment syndrome].

PubMed

Solmaz, Ilker; Talay, Mustafa; Tekindur, Şükrü; Kurt, Ercan

2012-01-01

Although abdominal cutaneous nerve entrapment syndrome (ACNES) is accepted as a rare condition, it is a syndrome that should be diagnosed more commonly when the clinical signs cannot explain the cause of abdominal pain. Abdominal pain is commonly considered by physicians to be based on intra-abdominal causes. Consequently, redundant tests and consultations are requested for these patients, and unnecessary surgical procedures may be applied. Patients with this type of pain are consulted to many clinics, and because their definitive diagnoses cannot be achieved, they are assessed as psychiatric patients. Actually, a common cause of abdominal wall pain is nerve entrapment on the lateral edge of the rectus abdominis muscle. In this paper, we would like to share information about the diagnosis and treatment of a patient who, prior to presenting to us, had applied to different clinics for chronic abdominal pain and had undergone many tests and consultations; abdominal surgery was eventually decided.

Effects of hawthorn on the progression of heart failure in a rat model of aortic constriction.

PubMed

Hwang, Hyun Seok; Boluyt, Marvin O; Converso, Kimber; Russell, Mark W; Bleske, Barry E

2009-06-01

To determine the effects of hawthorn (Crataegus oxycantha) on left ventricular remodeling and function in pressure overload-induced heart failure in an animal model. Randomized, parallel, dose-ranging animal study. University research facility. Seventy-four male Sprague-Dawley rats; 44 were included in the final analysis. Rats underwent a sham operation or aortic constriction. Rats subjected to the sham operation were treated with vehicle (10% agar-agar), and those subjected to aortic constriction were treated with vehicle or hawthorn (C. oxycantha special extract WS 1442) 1.3, 13, or 130 mg/kg for 5 months. Rats and their hearts were weighed, and echocardiographic measurements were performed at baseline and at 2, 3, 4, and 5 months after aortic constriction. Protein expression for markers of fibrosis and for atrial natriuretic factor was also measured. Aortic constriction increased the left ventricular:body weight ratio by 53% in vehicle-treated rats; Hawthorn treatment did not significantly affect the aortic constriction-induced increase in this ratio. Left ventricular volumes and dimensions at systole and diastole significantly increased 5 months after aortic constriction compared with baseline in rats given vehicle (> 20% increase, p<0.05) but not in those given hawthorn 130 mg/kg (< 10% increase). After aortic constriction, the velocity of circumferential shortening significantly decreased in the vehicle group but not in the medium- or high-dose groups. In the aortic constriction-vehicle group, the induced increases in messenger RNA expression for atrial natriuretic factor (approximately 1000%) and fibronectin (approximately 80%) were significantly attenuated by high-dose hawthorn treatment by approximately 80% and 50%, respectively. Hawthorn treatment exhibited modest beneficial effects on cardiac remodeling and function during long-term, pressure overload-induced heart failure in rats.

Single-Stage Resection of Type II Constriction Rings in Limbs on the Basis of Histologic and Magnetic Resonance Imaging Observations: A Retrospective Study of 21 Consecutive Patients.

PubMed

Jiang, Yongkang; Mao, Hailei; Yang, Xi; Zhou, Shengbo; Ni, Feng; Xu, Qiming; Wang, Bin

2016-07-01

The purpose of this study was to determine the feasibility of single-stage resection for type II congenital constriction rings by means of histologic examination of resected specimens and imaging examination of affected extremities, and to evaluate the appearance and function of the extremities after single-stage surgery. The features of the skin on the constriction rings and the subcutaneous tissues were identified through continuous sectioning, hematoxylin and eosin staining, and immunohistologic staining of specimens of type II constriction rings obtained by means of surgery. The relationship between the constriction rings and the deep main blood vessels was evaluated using magnetic resonance imaging. Single-stage resection of the constriction band, reduction of the fascial flap, and triangular flap-plasty were performed for 21 patients. The appearance, lymphedema, and movement of the extremities were compared before and after the operation. Type II constriction rings in the extremities had normal full-layer skin structures. Collagen was found deposited densely at the base of the grooves, but the normal subcutaneous tissue space remained, and the vital nerves and blood vessels were unaffected. Complete resection of the constriction rings was achieved in all 21 patients, and lymphedema subsided 2 months after the operation. No episode of recurrence was found, and limb function was not affected at 26-month follow-up. Type II congenital constriction rings in limbs possess normal subcutaneous tissue spaces. A single-stage operation, which includes complete resection of the rings, fascial flap reduction, and triangular flap-plasty, could achieve a satisfactory appearance and good function. Therapeutic, III.

Safe emergency department removal of a hardened steel penile constriction ring.

PubMed

Peay, Jeremy; Smithson, James; Nelson, James; Witucki, Peter

2009-10-01

Penile constriction devices are used for the enhancement of sexual performance. These devices have the potential to become incarcerated, leading to necrosis and amputation if not removed promptly. This article presents a step-by-step approach for the safe removal of a hardened steel penile constriction device using somewhat unorthodox tools found in a hospital. We present a case of an incarcerated hardened steel penile constriction ring that was not able to be removed with conventional techniques. We describe a novel technique using an electric grinder and laryngoscope blade. The technique described in this article is a valuable and relatively safe technique for the Emergency Physician to facilitate the timely removal of a hardened steel constriction device.

[Differential diagnosis of abdominal pain].

PubMed

Frei, Pascal

2015-09-02

Despite the frequency of functional abdominal pain, potentially dangerous causes of abdominal pain need to be excluded. Medical history and clinical examination must focus on red flags and signs for imflammatory or malignant diseases. See the patient twice in the case of severe and acute abdominal pain if lab parameters or radiological examinations are normal. Avoid repeated and useless X-ray exposure whenever possible. In the case of subacute or chronic abdominal pain, lab tests such as fecal calprotectin, helicobacter stool antigen and serological tests for celiac disease are very useful. Elderly patients may show atypical or missing clinical signs. Take care of red herrings and be skeptical whether your initial diagnosis is really correct. Abdominal pain can frequently be an abdominal wall pain.

Chronic Constriction Injury of the Infraorbital Nerve in the Rat using modified syringe needle

PubMed Central

Kernisant, Melanie; Gear, Robert; Jasmin, Luc; Vit, Jean-Philippe; Ohara, Peter T.

2008-01-01

Here we report a method for performing a chronic constriction injury (CCI) of the infraorbital nerve (ION) in the rat as a component of a chronic pain model. The surgical approach to the ION is described together with the use of a modified dental syringe needle that simplifies placing two chromic gut ligatures around the ION. This method makes the surgical procedure easier, the nerve injury more consistent across animals and reduces secondary damage to the ION and surrounding tissue. Pain behavior testing together with immunostaining for markers of nerve injury in the spinal trigeminal nucleus show the suitability of this procedure as a model of orofacial pain. PMID:18501433

Positive or negative fructose breath test results do not predict response to fructose restricted diet in children with recurrent abdominal pain: results from a prospective randomized trial.

PubMed

Wirth, S; Klodt, C; Wintermeyer, P; Berrang, J; Hensel, K; Langer, T; Heusch, A

2014-09-01

To perform a prospective, blinded, randomized interventional trial in patients with recurrent abdominal pain. The primary endpoint was to determine the abdominal pain intensity after 2 weeks of fructose restricted diet. Secondary endpoints were changes of pain frequency and a secondary symptom score (SSS). 103 individuals with recurrent abdominal pain for more than 3 months were randomized. 51 patients were allocated to group A (diet) and 52 to group B (no diet). 2 weeks later the patients underwent hydrogen breath test and were assigned to the test positive or negative group to identify patients with fructose malabsorption. 2 weeks after intervention the pain score decreased significantly from a median 5.5 in group A to 4 and did not change significantly in group B (5.3 to 5). In group A both patients with positive and negative breath tests had a significant lower pain score (-2 and -1.75, respectively). Frequency of abdominal pain decreased in both groups but without significant difference, SSS improved only in group A from median 6 to 3.5. Positive breath test was no predicting factor, neither was abdominal pain during the test. Fructose restricted diet in children and adolescents with recurrent abdominal pain may be of benefit to improve both abdominal pain symptoms and other secondary symptoms. Since a negative breath test result does not exclude a positive response to fructose restriction, the hydrogen breath test does not seem to be the appropriate diagnostic mean to predict the response to the diet. © Georg Thieme Verlag KG Stuttgart · New York.

Ultrasonographic identification of nerve pathology in neuralgic amyotrophy: Enlargement, constriction, fascicular entwinement, and torsion.

PubMed

Arányi, Zsuzsanna; Csillik, Anita; Dévay, Katalin; Rosero, Maja; Barsi, Péter; Böhm, Josef; Schelle, Thomas

2015-10-01

The aim of this study was to characterize the ultrasonographic findings on nerves in neuralgic amyotrophy. Fourteen patients with neuralgic amyotrophy were examined using high-resolution ultrasound. Four types of abnormalities were found: (1) focal or diffuse nerve/fascicle enlargement (57%); (2) incomplete nerve constriction (36%); (3) complete nerve constriction with torsion (50%; hourglass-like appearance); and (4) fascicular entwinement (28%). Torsions were confirmed intraoperatively and were seen on the radial nerve in 85% of patients. A significant correlation was found between no spontaneous recovery of nerve function and constriction/torsion/fascicular entwinement (P = 0.007). Ultrasonographic nerve pathology in neuralgic amyotrophy varies in order of severity from nerve enlargement to constriction to nerve torsion, with treatment ranging from conservative to surgical. We postulate that the constriction caused by inflammation is the precursor of torsion and that development of nerve torsion is facilitated by the rotational movements of limbs. © 2015 Wiley Periodicals, Inc.

Robust gap repair in the contractile ring ensures timely completion of cytokinesis

PubMed Central

Maiato, Helder; Pinto, Inês Mendes; Rubinstein, Boris

2016-01-01

Cytokinesis in animal cells requires the constriction of an actomyosin contractile ring, whose architecture and mechanism remain poorly understood. We use laser microsurgery to explore the biophysical properties of constricting rings in Caenorhabditis elegans embryos. Laser cutting causes rings to snap open. However, instead of disintegrating, ring topology recovers and constriction proceeds. In response to severing, a finite gap forms and is repaired by recruitment of new material in an actin polymerization–dependent manner. An open ring is able to constrict, and rings repair from successive cuts. After gap repair, an increase in constriction velocity allows cytokinesis to complete at the same time as controls. Our analysis demonstrates that tension in the ring increases while net cortical tension at the site of ingression decreases throughout constriction and suggests that cytokinesis is accomplished by contractile modules that assemble and contract autonomously, enabling local repair of the actomyosin network. Consequently, cytokinesis is a highly robust process impervious to discontinuities in contractile ring structure. PMID:27974482

Myosin concentration underlies cell size–dependent scalability of actomyosin ring constriction

PubMed Central

Wright, Graham D.; Leong, Fong Yew; Chiam, Keng-Hwee; Chen, Yinxiao; Jedd, Gregory; Balasubramanian, Mohan K.

2011-01-01

In eukaryotes, cytokinesis is accomplished by an actomyosin-based contractile ring. Although in Caenorhabditis elegans embryos larger cells divide at a faster rate than smaller cells, it remains unknown whether a similar mode of scalability operates in other cells. We investigated cytokinesis in the filamentous fungus Neurospora crassa, which exhibits a wide range of hyphal circumferences. We found that N. crassa cells divide using an actomyosin ring and larger rings constricted faster than smaller rings. However, unlike in C. elegans, the total amount of myosin remained constant throughout constriction, and there was a size-dependent increase in the starting concentration of myosin in the ring. We predict that the increased number of ring-associated myosin motors in larger rings leads to the increased constriction rate. Accordingly, reduction or inhibition of ring-associated myosin slows down the rate of constriction. Because the mechanical characteristics of contractile rings are conserved, we predict that these findings will be relevant to actomyosin ring constriction in other cell types. PMID:22123864

A new method for correcting type I and type II constricted (cup and lop) ears.

PubMed

Xiaogeng, Hu; Hongxing, Zhuang; Qinghua, Yang; Haiyue, Jiang; Yanyong, Zhao

2006-01-01

Tanzer suggested the term "constricted ear," denoting a spectrum of deformities limited to the superior third of the ear. Tanzer classified the constricted ear into three types. Type I ears have involvement of the helix, which usually is flattened. Type II ears show involvement of both the helix and the scapha. With type III ears, the auricle is rolled into a nearly tubular form that some authors regard as a form of microtia. The authors' new method for correcting the constricted ear varies in accordance with the diverse degree of deformity. The new method was used to correct constricted ears through a one-stage operation in eight type I cases. For the remaining six type 2 cases, the methods were combined with composite grafting. Most of the patients were satisfied with the final results. Therefore, the authors conclude that their approach is suitable for the treatment of type I and type II constricted ears.

Uncoupling apical constriction from tissue invagination

PubMed Central

Chung, SeYeon; Kim, Sangjoon; Andrew, Deborah J

2017-01-01

Apical constriction is a widely utilized cell shape change linked to folding, bending and invagination of polarized epithelia. It remains unclear how apical constriction is regulated spatiotemporally during tissue invagination and how this cellular process contributes to tube formation in different developmental contexts. Using Drosophila salivary gland (SG) invagination as a model, we show that regulation of folded gastrulation expression by the Fork head transcription factor is required for apicomedial accumulation of Rho kinase and non-muscle myosin II, which coordinate apical constriction. We demonstrate that neither loss of spatially coordinated apical constriction nor its complete blockage prevent internalization and tube formation, although such manipulations affect the geometry of invagination. When apical constriction is disrupted, compressing force generated by a tissue-level myosin cable contributes to SG invagination. We demonstrate that fully elongated polarized SGs can form outside the embryo, suggesting that tube formation and elongation are intrinsic properties of the SG. DOI: http://dx.doi.org/10.7554/eLife.22235.001 PMID:28263180

[Gallbladder contractility in children with functional abdominal pain or irritable bowel syndrome].

PubMed

Iwańczak, Franciszek; Siedlecka-Dawidko, Jolanta; Iwanczak, Barbara

2013-07-01

III Rome Criteria of functional gastrointestinal disorders in children, distinguished the disturbances with abdominal pain, to which irritable bowel syndrome, functional abdominal pains, functional dyspepsia and abdominal migraine were included. THE AIM OF THE STUDY was sonographic assessment of the gallbladder and its contractility in functional abdominal pain and irritable bowel syndrome in children. The study comprised 96 children aged 6 to 18 years, 59 girls and 37 boys. Depending on diagnosis, the children were divided into three groups. 38 children with functional abdominal pain constituted the first group, 26 children with irritable bowel syndrome were included to the second group, the third group consisted of 32 healthy children (control group). Diagnosis of functional abdominal pain and irritable bowel syndrome was made based on the III Rome Criteria. In irritable bowel syndrome both forms with diarrhea (13) and with constipation (13) were observed. Anatomy and contractility of the gallbladder were assessed by ultrasound examination. The presence of septum, wall thickness, thick bile, vesicle volume in fasting state and 30th and 60th minute after test meal were taken into consideration. Test meal comprised about 15% of caloric requirement of moderate metabolism. Children with bile stones and organic diseases were excluded from the study. Thickened vesicle wall and thick bile were present more frequently in children with irritable bowel syndrome and functional abdominal pain than in control group (p < 0.02). Fasting vesicle volume was significantly greater in children with functional abdominal pain than in irritable bowel syndrome and control group (p = 0.003, p = 0.05). Vesicle contractility after test meal was greatest in children with functional abdominal pain. Evaluation of diminished (smaller than 30%) and enlarged (greater then 80%) gallbladder contractility at 30th and 60th minute after test meal demonstrated disturbances of contractility in children with irritable bowel syndrome and functional abdominal pain. In children with functional abdominal pain and irritable bowel syndrome disturbances of gallbladder anatomy, fasting volume and contractility after test meal were demonstrated. The observed disturbances require further studies for explanation of their role in functional gastrointestinal disturbances with abdominal pain in children.

Effects of the tripeptide substance P antagonist, FR113680, on airway constriction and airway edema induced by neurokinins in guinea-pigs.

PubMed

Murai, M; Morimoto, H; Maeda, Y; Fujii, T

1992-06-24

FR113680 is a newly developed tripeptide substance P (SP) receptor antagonist. The effects of FR113680 on airway constriction and airway edema induced by neurokinins were investigated in guinea-pigs. In in vitro experiments, FR113680 inhibited the contraction of isolated guinea-pig trachea induced by SP and neurokinin A (NKA) in a dose-dependent manner with IC50 values of 2.3 x 10(-6) and 1.5 x 10(-5) M, respectively. The tracheal contraction induced by histamine and acetylcholine was not affected by FR113680. FR113680 (5 x 10(-5) M) also significantly inhibited the atropine-resistant contraction of isolated guinea-pig bronchi induced by electrical field stimulation. In in vivo experiments, FR113680 given i.v. inhibited SP-induced airway constriction in guinea-pigs at doses of 1 and 10 mg kg-1. However, FR113680 only inhibited NKA- and capsaicin-induced airway constriction by 40-50% even at a dose of 10 mg kg-1. FR113680 also inhibited SP-induced airway edema in guinea-pigs with the same potency as it inhibited SP-induced airway constriction. Histamine-induced airway constriction and airway edema were not affected at a dose of 10 mg kg-1. These results suggest that FR113680 preferentially inhibits responses induced by NK1 receptor activation (SP-induced airway constriction and airway edema), but is less effective on a NK2 receptor-induced response (airway constriction by NKA and neurogenic stimulation).

The influences of temperature and naloxone on the antinociceptive activity of Corchorus olitorius L. in mice.

PubMed

Zakaria, Z A; Safarul, M; Valsala, R; Sulaiman, M R; Fatimah, C A; Somchit, M N; Mat Jais, A M

2005-07-01

A series of preliminary studies was carried out to evaluate the antinociceptive (pain relief) activity of the aqueous extract of Corchorus olitorius L. leaves (COAE) and to determine the influence of temperature and opioid receptors on COAE activity using the abdominal constriction and hot plate tests in mice. COAE, at concentrations of 10, 25, 50, 75, and 100%, showed both peripheral and central antinociception that are non-concentration- and concentration-dependent respectively. The peripheral activity was clearly observed at a concentration of 25% and diminished at a concentration of 100%, while the central activity was observed at all the concentrations of COAE used. Furthermore, the insignificant results obtained indicated that this peripheral activity (at concentrations of 25 and 50%) was comparable to that of morphine (0.8 mg/kg). Pre-heating COAE at a temperature of 80 degrees C and 100 degrees C, or 60 degrees C and 80 degrees C was found to enhance its peripheral and central antinociception respectively. Pre-treatment with naloxone (10 mg/kg), a general opioid receptor antagonist, for 5 min, followed by COAE, was found to completely block its peripheral, but not central, antinociceptive activity. Based on this observation, we conclude that the antinociceptive activity exhibited by C. olitorius is enhanced by the increase in temperature and may be mediated peripherally, but not centrally, at least in part, via an opioid receptor.

A Microfluidic Technique to Probe Cell Deformability

PubMed Central

Hoelzle, David J.; Varghese, Bino A.; Chan, Clara K.; Rowat, Amy C.

2014-01-01

Here we detail the design, fabrication, and use of a microfluidic device to evaluate the deformability of a large number of individual cells in an efficient manner. Typically, data for ~102 cells can be acquired within a 1 hr experiment. An automated image analysis program enables efficient post-experiment analysis of image data, enabling processing to be complete within a few hours. Our device geometry is unique in that cells must deform through a series of micron-scale constrictions, thereby enabling the initial deformation and time-dependent relaxation of individual cells to be assayed. The applicability of this method to human promyelocytic leukemia (HL-60) cells is demonstrated. Driving cells to deform through micron-scale constrictions using pressure-driven flow, we observe that human promyelocytic (HL-60) cells momentarily occlude the first constriction for a median time of 9.3 msec before passaging more quickly through the subsequent constrictions with a median transit time of 4.0 msec per constriction. By contrast, all-trans retinoic acid-treated (neutrophil-type) HL-60 cells occlude the first constriction for only 4.3 msec before passaging through the subsequent constrictions with a median transit time of 3.3 msec. This method can provide insight into the viscoelastic nature of cells, and ultimately reveal the molecular origins of this behavior. PMID:25226269

Modulation of apical constriction by Wnt signaling is required for lung epithelial shape transition.

PubMed

Fumoto, Katsumi; Takigawa-Imamura, Hisako; Sumiyama, Kenta; Kaneiwa, Tomoyuki; Kikuchi, Akira

2017-01-01

In lung development, the apically constricted columnar epithelium forms numerous buds during the pseudoglandular stage. Subsequently, these epithelial cells change shape into the flat or cuboidal pneumocytes that form the air sacs during the canalicular and saccular (canalicular-saccular) stages, yet the impact of cell shape on tissue morphogenesis remains unclear. Here, we show that the expression of Wnt components is decreased in the canalicular-saccular stages, and that genetically constitutive activation of Wnt signaling impairs air sac formation by inducing apical constriction in the epithelium as seen in the pseudoglandular stage. Organ culture models also demonstrate that Wnt signaling induces apical constriction through apical actomyosin cytoskeletal organization. Mathematical modeling reveals that apical constriction induces bud formation and that loss of apical constriction is required for the formation of an air sac-like structure. We identify MAP/microtubule affinity-regulating kinase 1 (Mark1) as a downstream molecule of Wnt signaling and show that it is required for apical cytoskeletal organization and bud formation. These results suggest that Wnt signaling is required for bud formation by inducing apical constriction during the pseudoglandular stage, whereas loss of Wnt signaling is necessary for air sac formation in the canalicular-saccular stages. © 2017. Published by The Company of Biologists Ltd.

Phytochemical composition and antinociceptive activity of Bauhinia glauca subsp. hupehana in rats.

PubMed

Xu, Jinlong; Zhao, Qizhi; Wei, Lei; Yang, Yu; Xu, Rui; Yu, Nengjiang; Zhao, Yimin

2015-01-01

In traditional medicine, Bauhinia glauca subsp. hupehana has long been used as an analgesic agent in China. The aim of this study was to evaluate the antinociceptive activity of the ethanol extract of the aerial parts of B. glauca subsp. hupehana (BHE) in rats and its chemical fingerprint. The antinociceptive activity of BHE was assessed in mice using chemically and heat-induced pain models, such as the acetic acid-induced writhing, hot plate, tail-flick and glutamate tests. Naltrexone hydrochloride, a non-selective opioid receptor antagonist, was utilized to determine the involvement of the opioid system. In addition to this, the involvements of the cGMP and ATP-sensitive K+ channel pathways were also detected using methylene blue and glibenclamide. The oral administration of BHE (at doses of 50, 100 and 200 mg/kg) produced significant and dose-related inhibitions in both the chemically and heat-induced pain models. Interestingly, in the abdominal constriction test, when the dose of BHE was increased to 800 mg/kg (p.o., n = 10), the inhibition rate was 100%. The antinociceptive mechanism may involve the cGMP pathway and ATP sensitive K+ channel pathway. The central antinociceptive effect was not antagonized by naltrexone. One phenolic acid, one lignin and five flavonoids were isolated from BHE. The antinociceptive activity of BHE was most likely due to the presence of the flavonoids. The acute toxicity results showed that BHE was safe at a high dose (2 g/kg, p.o.). The current investigation demonstrates that B. glauca subsp. hupehana is a potential candidate for the development of novel, non-opioid, analgesic phytomedicines.

Development of a microfluidic device for cell concentration and blood cell-plasma separation.

PubMed

Maria, M Sneha; Kumar, B S; Chandra, T S; Sen, A K

2015-12-01

This work presents design, fabrication and test of a microfluidic device which employs Fahraeus-Lindqvist and Zweifach-Fung effects for cell concentration and blood cell-plasma separation. The device design comprises a straight main channel with a series of branched channels placed symmetrically on both sides of the main channel. The design implements constrictions before each junction (branching point) in order to direct cells that would have migrated closer to the wall (naturally or after liquid extraction at a junction) towards the centre of the main channel. Theoretical and numerical analysis are performed for design of the microchannel network to ensure that a minimum flow rate ratio (of 2.5:1, main channel-to-side channels) is maintained at each junction and predict flow rate at the plasma outlet. The dimensions and location of the constrictions were determined using numerical simulations. The effect of presence of constrictions before the junctions was demonstrated by comparing the performances of the device with and without constrictions. To demonstrate the performance of the device, initial experiments were performed with polystyrene microbeads (10 and 15 μm size) and droplets. Finally, the device was used for concentration of HL60 cells and separation of plasma and cells in diluted blood samples. The cell concentration and blood-plasma purification efficiency was quantified using Haemocytometer and Fluorescence-Activated Cell Sorter (FACS). A seven-fold cell concentration was obtained with HL60 cells and a purification efficiency of 70 % and plasma recovery of 80 % was observed for diluted (1:20) blood sample. FACS was used to identify cell lysis and the cell viability was checked using Trypan Blue test which showed that more than 99 % cells are alive indicating the suitability of the device for practical use. The proposed device has potential to be used as a sample preparation module in lab on chip based diagnostic platforms.

The effect of concentric constriction of the visual field to 10 and 15 degrees on simulated motor vehicle accidents

PubMed Central

Udagawa, Sachiko; Iwase, Aiko; Susuki, Yuto; Kunimatsu-Sanuki, Shiho; Fukuchi, Takeo; Matsumoto, Chota; Ohno, Yuko; Ono, Hiroshi; Sugiyama, Kazuhisa; Araie, Makoto

2018-01-01

Purpose Traffic accidents are associated with the visual function of drivers, as well as many other factors. Driving simulator systems have the advantage of controlling for traffic- and automobile-related conditions, and using pinhole glasses can control the degree of concentric concentration of the visual field. We evaluated the effect of concentric constriction of the visual field on automobile driving, using driving simulator tests. Methods Subjects meeting criteria for normal eyesight were included in the study. Pinhole glasses with variable aperture sizes were adjusted to mimic the conditions of concentric visual field constrictions of 10° and 15°, using a CLOCK CHART®. The test contained 8 scenarios (2 oncoming right-turning cars and 6 jump-out events from the side). Results Eighty-eight subjects were included in the study; 37 (mean age = 52.9±15.8 years) subjects were assigned to the 15° group, and 51 (mean = 48.6±15.5 years) were assigned to the 10° group. For all 8 scenarios, the number of accidents was significantly higher among pinhole wearing subjects. The average number of all types of accidents per person was significantly higher in the pinhole 10° group (4.59±1.81) than the pinhole 15° group (3.68±1.49) (P = 0.032). The number of accidents associated with jump-out scenarios, in which a vehicle approaches from the side on a straight road with a good view, was significantly higher in the pinhole 10° group than in the pinhole 15° group. Conclusions Concentric constriction of the visual field was associated with increased number of traffic accidents. The simulation findings indicated that a visual field of 10° to 15° may be important for avoiding collisions in places where there is a straight road with a good view. PMID:29538425

[Clinical Approach to Abdominal Pain as Functional Origin].

PubMed

Ryu, Han Seung; Choi, Suck Chei

2018-02-25

Abdominal pain is a common symptom that patients refer to a hospital. Organic causes should be differentiated in patients with abdominal pain and treatment should be administered in accordance with the causes. A meticulous history taking and physical examination are highly useful in making a diagnosis, and blood tests, imaging modalities, and endoscopy are useful for confirming diagnosis. However, in many cases, patients have functional disorders with no obvious abnormal findings obtained even if many diagnostic tests are performed. Patients with functional disorders usually complain the vague abdominal pain located in the center and other portions of the abdominal area. Although the most representative disease is irritable bowel syndrome, functional abdominal pain syndrome is currently researched as a new disease entity of functional abdominal pain. As various receptors related to functional abdominal pain have been discovered, drugs associated with those receptors are used to treat the disorders, and additional new drugs are vigorously developed. In addition, medical therapy with pharmacological or non-pharmacological psychiatric treatment is effective for treating functional abdominal pain.

Rate and topography of peptidoglycan synthesis during cell division in Escherichia coli: Concept of a leading edge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wientjes, F.B.; Nanninga, N.

1989-06-01

The rate at which the peptidoglycan of Escherichia coli is synthesized during the division cycle was studied with two methods. One method involved synchronization of E. coli MC4100 lysA cultures by centrifugal elutriation and subsequent pulse-labeling of the synchronously growing cultures with (meso-{sup 3}H)diaminopimelic acid (({sup 3}H)Dap). The second method was autoradiography of cells pulse-labeled with ({sup 3}H)Dap. It was found that the peptidoglycan is synthesized at a more or less exponentially increasing rate during the division cycle with a slight acceleration in this rate as the cells start to constrict. Apparently, polar cap formation requires synthesis of extra surfacemore » components, presumably to accommodate for a change in the surface-to-volume ratio. Furthermore, it was found that the pool size of Dap was constant during the division cycle. Close analysis of the topography of ({sup 3}H)Dap incorporation at the constriction site revealed that constriction proceeded by synthesis of peptidoglycan at the leading edge of the invaginating cell envelope. During constriction, no reallocation of incorporation occurred, i.e., the incorporation at the leading edge remained high throughout the process of constriction. Impairment of penicillin-binding protein 3 by mutation or by the specific {beta}-lactam antibiotic furazlocillin did not affect ({sup 3}H)Dap incorporation during initiation of constriction. However, the incorporation at the constriction site was inhibited in later stages of the constriction process. It is concluded that during division at least two peptidoglycan-synthesizing systems are operating sequentially.« less

Evaluating abdominal core muscle fatigue: Assessment of the validity and reliability of the prone bridging test.

PubMed

De Blaiser, C; De Ridder, R; Willems, T; Danneels, L; Vanden Bossche, L; Palmans, T; Roosen, P

2018-02-01

The aims of this study were to research the amplitude and median frequency characteristics of selected abdominal, back, and hip muscles of healthy subjects during a prone bridging endurance test, based on surface electromyography (sEMG), (a) to determine if the prone bridging test is a valid field test to measure abdominal muscle fatigue, and (b) to evaluate if the current method of administrating the prone bridging test is reliable. Thirty healthy subjects participated in this experiment. The sEMG activity of seven abdominal, back, and hip muscles was bilaterally measured. Normalized median frequencies were computed from the EMG power spectra. The prone bridging tests were repeated on separate days to evaluate inter and intratester reliability. Significant differences in normalized median frequency slope (NMF slope ) values between several abdominal, back, and hip muscles could be demonstrated. Moderate-to-high correlation coefficients were shown between NMF slope values and endurance time. Multiple backward linear regression revealed that the test endurance time could only be significantly predicted by the NMF slope of the rectus abdominis. Statistical analysis showed excellent reliability (ICC=0.87-0.89). The findings of this study support the validity and reliability of the prone bridging test for evaluating abdominal muscle fatigue. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Prolonged fever in peritoneal tuberculosis: A case report

NASA Astrophysics Data System (ADS)

Zein, U.; Irwandi, S.; Habib, H.; Lim, H.; Pasha, M.; Janis, I.; Saragih, R. H.; Ginting, Y.; Effendy-Y S, R.

2018-03-01

Peritoneal tuberculosis may lead to delayed diagnosis because of the nonspecific features such as fever, abdominal distension, abdominal tenderness, ascites, and weight loss. Here, wereported a case of prolonged fever and abdominal pain which was due to peritoneal tuberculosis. Initial examinations including acomplete blood test and serologic tests did not lead to the diagnosis. A final diagnosis was made by abdominal CT-scan and laparoscopy combined with histopathological studies. Antituberculous medications provided a good clinical response in this patient.

Pericardial constriction after cardiac transplantation.

PubMed

Bansal, Ramesh; Perez, Leandro; Razzouk, Anees; Wang, Nan; Bailey, Leonard

2010-03-01

In this study we present a series of 5 cases that developed constrictive pericarditis after orthotopic heart transplantation. All 5 patients had pericardial effusion of non-infectious etiology in the early post-transplant period. They subsequently presented with heart failure unresponsive to standard medical management. The diagnosis was made by comprehensive echo-Doppler studies. Findings were confirmed at surgical inspection and complete pericardiectomy led to improvement in hemodynamics in 4 patients. One patient had relief from constriction but died of non-cardiac complications. One patient with constriction has been re-listed for transplantation due to intermittent heart block and associated cardiac allograft vasculopathy. Early diagnosis of pericardial constriction after orthotopic heart transplantation requires a high index of clinical suspicion and optimal use of Doppler echocardiography. Early diagnosis and timely surgical pericardiectomy may correct this condition entirely and result in satisfactory long-term results.

Apical constriction: themes and variations on a cellular mechanism driving morphogenesis

PubMed Central

Martin, Adam C.; Goldstein, Bob

2014-01-01

Apical constriction is a cell shape change that promotes tissue remodeling in a variety of homeostatic and developmental contexts, including gastrulation in many organisms and neural tube formation in vertebrates. In recent years, progress has been made towards understanding how the distinct cell biological processes that together drive apical constriction are coordinated. These processes include the contraction of actin-myosin networks, which generates force, and the attachment of actin networks to cell-cell junctions, which allows forces to be transmitted between cells. Different cell types regulate contractility and adhesion in unique ways, resulting in apical constriction with varying dynamics and subcellular organizations, as well as a variety of resulting tissue shape changes. Understanding both the common themes and the variations in apical constriction mechanisms promises to provide insight into the mechanics that underlie tissue morphogenesis. PMID:24803648

A corkscrew model for dynamin constriction.

PubMed

Mears, Jason A; Ray, Pampa; Hinshaw, Jenny E

2007-10-01

Numerous vesiculation processes throughout the eukaryotic cell are dependent on the protein dynamin, a large GTPase that constricts lipid bilayers. We have combined X-ray crystallography and cryo-electron microscopy (cryo-EM) data to generate a coherent model of dynamin-mediated membrane constriction. GTPase and pleckstrin homology domains of dynamin were fit to cryo-EM structures of human dynamin helices bound to lipid in nonconstricted and constricted states. Proteolysis and immunogold labeling experiments confirm the topology of dynamin domains predicted from the helical arrays. Based on the fitting, an observed twisting motion of the GTPase, middle, and GTPase effector domains coincides with conformational changes determined by cryo-EM. We propose a corkscrew model for dynamin constriction based on these motions and predict regions of sequence important for dynamin function as potential targets for future mutagenic and structural studies.

Peptide-induced prostaglandin biosynthesis in the renal-vein-constricted kidney

PubMed Central

Myers, Stuart I.; Zipser, Robert; Needleman, Philip

1981-01-01

The ipsilateral kidney was removed from a rabbit 48h after unilateral partial renal-vein-constriction and was perfused with Krebs–Henseleit media at 37°C. Hourly administration of a fixed dose of bradykinin to the renal-vein-constricted kidney demonstrated a marked time-dependent increase in the release of bioassayable prostaglandin E2 and thromboxane A2 into the venous effluent as compared with the response of the contralateral control kidney. The renal-vein-constricted kidney produced up to 60 times more prostaglandin E2 in response to bradykinin after 6h of perfusion as compared with the contralateral kidney; thromboxane A2 was not demonstratable in the contralateral kidney. Inhibition of protein synthesis de novo in the perfused renal-vein-constricted kidney with cycloheximide lessened the hormone-stimulated increase in prostaglandin E2 by 94% and in thromboxane A2 by 90% at 6h of perfusion. Covalent acetylation of the renal cyclo-oxygenase by prior oral administration of aspirin to the rabbit inhibited initial bradykinin-stimulated prostaglandin E2 biosynthesis 71% at 1h of perfusion. However, there was total recovery from aspirin in the renal-vein-constricted kidney by 2h of perfusion after bradykinin stimulation. Total cyclo-oxygenase activity as measured by [14C]arachidonate metabolism to labelled prostaglandins by renal cortical and renal medullary microsomal fractions prepared from 6h-perfused kidneys demonstrated that renal-vein-constricted kidney-cortical cyclo-oxygenase activity was significantly greater than the contralateral-kidney-cortical conversion, whereas medullary arachidonate metabolism was comparable in both the renal-vein-constricted kidney and contralateral kidney. These data suggest that perfusion of a renal-vein-constricted kidney initiates a time-dependent induction of synthesis of prostaglandin-producing enzymes, which appear to be primarily localized in the renal cortex. The presence of the synthetic capacity to generate very potent vasodilator and vasoconstrictor prostaglandins in the renal cortex suggests that these substances could mediate or modulate changes in renal vascular resistance in pathological states. PMID:6798974

Effects of channel constriction on upstream steering of flow around Locke Island, Columbia River, Washington

NASA Astrophysics Data System (ADS)

Loy, G. E.; Furbish, D. J.; Covey, A.

2010-12-01

Landsliding of the White Bluffs along the Columbia River in Washington State has constricted the width of the river on one side of Locke Island, a two-kilometer long island positioned in the middle of the channel. Associated changes in flow are thought to be causing relatively rapid erosion of Locke Island on the constricted side. This island is of cultural significance to Native American tribes of south-central Washington, so there are social as well as scientific reasons to understand how the alteration of stream channel processes resulting from the landsliding might be influencing observed erosion rates. Simple hydrodynamic calculations suggest that the constriction on one side of the island creates an upstream backwater effect. As a consequence a cross-stream pressure gradient upstream of the island results in steering of flow around the island into the unobstructed thread. This diversion of water decreases the discharge through the constriction. Therefore, flow velocities within the constriction are not necessarily expected to be higher than those in the unobstructed thread, contrary to initial reports suggesting that higher velocities within the constriction are the main cause of erosion. We set up streamtable experiments with lapse rate imaging to illustrate the backwater effects of the channel constriction and the associated cross-stream steering of flow around a model island. Our experiments are scaled by channel roughness and slope rather than geometrically, as the main focus is to understand the mechanical behavior of flow in this type of island-landslide system. In addition, we studied the stream velocities and flow steering as well as the magnitude of the backwater effect in both the constricted and unobstructed channels using tracer particles in the time-lapse images. These experimental data are compared with calculated upstream backwater distances determined from the known water-surface slope, flow depth, total discharge, and bed roughness. Furthermore, this experimental work will inform subsequent numerical modeling of flow and field-based measurements at Locke Island.

Droplet squeezing through a narrow constriction: Minimum impulse and critical velocity

NASA Astrophysics Data System (ADS)

Zhang, Zhifeng; Drapaca, Corina; Chen, Xiaolin; Xu, Jie

2017-07-01

Models of a droplet passing through narrow constrictions have wide applications in science and engineering. In this paper, we report our findings on the minimum impulse (momentum change) of pushing a droplet through a narrow circular constriction. The existence of this minimum impulse is mathematically derived and numerically verified. The minimum impulse happens at a critical velocity when the time-averaged Young-Laplace pressure balances the total minor pressure loss in the constriction. Finally, numerical simulations are conducted to verify these concepts. These results could be relevant to problems of energy optimization and studies of chemical and biomedical systems.

Sentinel case of group A beta-hemolytic streptococcus causing constrictive pericarditis presenting as hypogammaglobulinemia.

PubMed

Ahmadian, Homayoun R; Tankersley, Michael; Otto, Hans

2011-05-01

This is a unique case of a previously healthy 7-year-old boy, which highlights the importance of considering immunodeficiency when a rare infection occurs. In the following case report, the patient develops constrictive pericarditis secondary to group A beta-hemolytic streptococcal infection. As a result of this infection, we speculate that he develops hypogammaglobulinemia secondary to the documented association between constrictive pericarditis and intestinal lymphangiectasia because an extensive work-up for a primary immunodeficiency was negative. This is the first case ever to present constrictive pericarditis because of group A beta-hemolytic streptococcal infection.

Abdominal insufflation for laparoscopy increases intracranial and intrathoracic pressure in human subjects.

PubMed

Kamine, Tovy Haber; Elmadhun, Nassrene Y; Kasper, Ekkehard M; Papavassiliou, Efstathios; Schneider, Benjamin E

2016-09-01

Laparoscopy has emerged as an alternative to laparotomy in select trauma patients. In animal models, increasing abdominal pressure is associated with an increase in intrathoracic and intracranial pressures. We conducted a prospective trial of human subjects who underwent laparoscopic-assisted ventriculoperitoneal shunt placement (lap VPS) with intraoperative measurement of intrathoracic, intracranial and cerebral perfusion pressures. Ten patients undergoing lap VPS were recruited. Abdominal insufflation was performed using CO2 to 0, 8, 10, 12 and 15 mmHg. ICP was measured through the ventricular catheter simultaneously with insufflation and with desufflation using a manometer. Peak inspiratory pressures (PIP) were measured through the endotracheal tube. Blood pressure was measured using a noninvasive blood pressure cuff. End-tidal CO2 (ETCO2) was measured for each set of abdominal pressure level. Pressure measurements from all points of insufflation were compared using a two-way ANOVA with a post hoc Bonferroni test. Mean changes in pressures were compared using t test. ICP and PIP increased significantly with increasing abdominal pressure (both p < 0.01), whereas cerebral perfusion pressure (CPP) and mean arterial pressure did not significantly change with increasing abdominal pressure over the range tested. Higher abdominal pressure values were associated with decreased ETCO2 values. Increased ICP and PIP appear to be a direct result of increasing abdominal pressure, since ETCO2 did not increase. Though CPP did not change over the range tested, the ICP in some patients with 15 mmHg abdominal insufflation reached values as high as 32 cmH2O, which is considered above tolerance, regardless of the CPP. Laparoscopy should be used cautiously, in patients who present with baseline elevated ICP or head trauma as abdominal insufflation affects intracranial pressure.

Validity and reliability of the abdominal test and evaluation systems tool (ABTEST) to accurately measure abdominal force.

PubMed

Glenn, Jordan M; Galey, Madeline; Edwards, Abigail; Rickert, Bradley; Washington, Tyrone A

2015-07-01

Ability to generate force from the core musculature is a critical factor for sports and general activities with insufficiencies predisposing individuals to injury. This study evaluated isometric force production as a valid and reliable method of assessing abdominal force using the abdominal test and evaluation systems tool (ABTEST). Secondary analysis estimated 1-repetition maximum on commercially available abdominal machine compared to maximum force and average power on ABTEST system. This study utilized test-retest reliability and comparative analysis for validity. Reliability was measured using test-retest design on ABTEST. Validity was measured via comparison to estimated 1-repetition maximum on a commercially available abdominal device. Participants applied isometric, abdominal force against a transducer and muscular activation was evaluated measuring normalized electromyographic activity at the rectus-abdominus, rectus-femoris, and erector-spinae. Test, re-test force production on ABTEST was significantly correlated (r=0.84; p<0.001). Mean electromyographic activity for the rectus-abdominus (72.93% and 75.66%), rectus-femoris (6.59% and 6.51%), and erector-spinae (6.82% and 5.48%) were observed for trial-1 and trial-2, respectively. Significant correlations for the estimated 1-repetition maximum were found for average power (r=0.70, p=0.002) and maximum force (r=0.72, p<0.001). Data indicate the ABTEST can accurately measure rectus-abdominus force isolated from hip-flexor involvement. Negligible activation of erector-spinae substantiates little subjective effort among participants in the lower back. Results suggest ABTEST is a valid and reliable method of evaluating abdominal force. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Role of sensory C fibers in hypoxia/ reoxygenation-impaired myogenic constriction of cerebral arteries

PubMed Central

Xie, Hui; Ray, Patricio E.; Short, Billie Lou

2009-01-01

Objective Hypoxia/reoxygenation (H/R) associated with extracorporeal membrane oxygenation disrupts cerebral autoregulation. However, the underlying mechanisms remain poorly understood. The present study was designed to investigate the role of sensory C-fibers in myogenic responsiveness of cerebral arteries. Methods Arterial diameter and intraluminal pressure were simultaneously measured in vitro on rat posterior cerebral arteries. Results Cerebral arteries constricted in response to graded increase in intraluminal pressure (20–100 mmHg, in 20 mmHg increments). In vitro C-fiber desensitization with capsaicin (1 μmol/l, 20 minutes) significantly suppressed myogenic constriction by over 50%, but did not affect 5-hydroxytryptamine (0.01–10 μmol/l) and KCl (120 mmol/l)-induced constriction. Capsazepine (5 μmol/l, 30 minutes), a selective blocker of neuronal vanilloid receptor TRPV1, had similar inhibitory effect on cerebral myogenic constriction to elevated pressure. Cerebral myogenic constriction was significantly attenuated by H/R; the impairment by H/R was further enhanced after C-fiber desensitization (except at a pressure level of 100 mmHg). Discussion These findings indicate that C-fiber activity contributes to myogenic constriction of cerebral arteries under normal and H/R conditions. H/R-impaired myogenic responsiveness is exaggerated by C-fiber dysfunction. These results raise the possibility that therapeutic strategies directed toward preserving C-fiber nerve endings or supplying its constituent neuropeptides could be developed. PMID:19570322

Behavioral and anatomical characterization of the bilateral sciatic nerve chronic constriction (bCCI) injury: correlation of anatomic changes and responses to cold stimuli

PubMed Central

2010-01-01

Background Unilateral constrictive sciatic nerve injury (uCCI) is a common neuropathic pain model. However, the bilateral constrictive injury (bCCI) model is less well studied, and shows unique characteristics. In the present study, we sought to correlate effects of bCCI on nocifensive responses to cold and mechanical stimuli with selected dorsal horn anatomic markers. bCCI or sham ligation of both rat sciatic nerves were followed up to 90 days of behavioural testing. Additional rats sacrificed at 15, 30 and 90 days were used for anatomic analyses. Behavioural tests included hindpaw withdrawal responses to topical acetone, cold plate testing, an operant thermal preference task and hindpaw withdrawal thresholds to mechanical probing. Results All nocifensive responses to cold increased and remained enhanced for >45 days. Mechanical withdrawal thresholds decreased for 25 days only. Densitometric analyses of immunoperoxidase staining in the superficial dorsal horn at L4-5 revealed decreased cholecystokinin (CCK) staining at all times after bCCI, decreased mu opiate receptor (MOR) staining, maximal at 15 days, increased neuropeptide Y (NPY) staining only at days 15 and 30, and increased neurokinin-1 receptor (NK-1R) staining at all time points, maximal at 15 days. Correlation analyses at 45 days post-bCCI, were significant for individual rat nocifensive responses in each cold test and CCK and NK-1R, but not for MOR or NPY. Conclusions These results confirm the usefulness of cold testing in bCCI rats, a new approach using CCI to model neuropathic pain, and suggest a potential value of studying the roles of dorsal horn CCK and substance P in chronic neuropathic pain. Compared to human subjects with neuropathic pain, responses to cold stimuli in rats with bCCI may be a useful model of neuropathic pain. PMID:20105332

Behavioral and anatomical characterization of the bilateral sciatic nerve chronic constriction (bCCI) injury: correlation of anatomic changes and responses to cold stimuli.

PubMed

Datta, Sukdeb; Chatterjee, Koel; Kline, Robert H; Wiley, Ronald G

2010-01-27

Unilateral constrictive sciatic nerve injury (uCCI) is a common neuropathic pain model. However, the bilateral constrictive injury (bCCI) model is less well studied, and shows unique characteristics. In the present study, we sought to correlate effects of bCCI on nocifensive responses to cold and mechanical stimuli with selected dorsal horn anatomic markers. bCCI or sham ligation of both rat sciatic nerves were followed up to 90 days of behavioural testing. Additional rats sacrificed at 15, 30 and 90 days were used for anatomic analyses. Behavioural tests included hindpaw withdrawal responses to topical acetone, cold plate testing, an operant thermal preference task and hindpaw withdrawal thresholds to mechanical probing. All nocifensive responses to cold increased and remained enhanced for >45 days. Mechanical withdrawal thresholds decreased for 25 days only. Densitometric analyses of immunoperoxidase staining in the superficial dorsal horn at L4-5 revealed decreased cholecystokinin (CCK) staining at all times after bCCI, decreased mu opiate receptor (MOR) staining, maximal at 15 days, increased neuropeptide Y (NPY) staining only at days 15 and 30, and increased neurokinin-1 receptor (NK-1R) staining at all time points, maximal at 15 days. Correlation analyses at 45 days post-bCCI, were significant for individual rat nocifensive responses in each cold test and CCK and NK-1R, but not for MOR or NPY. These results confirm the usefulness of cold testing in bCCI rats, a new approach using CCI to model neuropathic pain, and suggest a potential value of studying the roles of dorsal horn CCK and substance P in chronic neuropathic pain. Compared to human subjects with neuropathic pain, responses to cold stimuli in rats with bCCI may be a useful model of neuropathic pain.

Effects of microRNA-223 on morphine analgesic tolerance by targeting NLRP3 in a rat model of neuropathic pain

PubMed Central

Xie, Xiao-Juan; Ma, Li-Gang; Xi, Kai; Fan, Dong-Mei; Li, Jian-Guo; Zhang, Quan; Zhang, Wei

2017-01-01

Objective To investigate the effects of microRNA-223 on morphine analgesic tolerance by targeting NLRP3 in a rat model of neuropathic pain. Methods Our study selected 100 clean grade healthy Sprague-Dawley adult male rats weighing 200 to 250 g. After establishment of a rat model of chronic constriction injury, these rats were divided into 10 groups (10 rats in each group): the normal control, sham operation, chronic constriction injury, normal saline, morphine, miR-223, NLRP3, miR-223 + morphine, NLRP3 + morphine, and miR-223 + NLRP3 + morphine groups. The real-time quantitative polymerase chain reaction assay, Western blotting, and enzyme-linked immunosorbent assay were used for detecting the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, Interleukin (IL)-1β, and IL-18 in sections of lumbar spinal cord. Immunohistochemistry was applied for detecting the positive rates of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18. Results The paw withdrawal threshold and percentage maximum possible effect (%MPE) were higher in chronic constriction injury group when compared with the normal control and sham operation groups. Behavioral tests showed that compared with the chronic constriction injury and normal saline groups, the morphine and miR-223 + morphine groups showed obvious analgesic effects. Expressions of miR-223 in the miR-223, miR-223 + morphine, and miR-223 + NLRP3 + morphine were significantly higher than those in the chronic constriction injury, normal saline, and morphine groups. Compared with chronic constriction injury, normal saline and morphine groups, the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18 were significantly decreased in the miR-223 and miR-223 + morphine groups, while mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18 were significantly increased in the NLRP3 and NLRP3 + morphine group. Conclusion Our study provides strong evidence that miR-223 could suppress the activities of NLRP3 inflammasomes (NLRP3, apoptosis-associated speck-like protein, and Caspase-1) to relieve morphine analgesic tolerance in rats by down-regulating NLRP3. PMID:28580822

Waldmann's Disease (Primary Intestinal Lymphangiectasia) with Atrial Septal Defect.

PubMed

Aroor, Shrikiran; Mundkur, Suneel; Kanaparthi, Shravan; Kumar, Sandeep

2017-04-01

Waldmann's disease or Primary Intestinal Lymphangiectasia (PIL) is a rare disorder of gastrointestinal tract characterized by dilated lymphatics and widened villi causing leakage of lymph into intestinal lumen. Loss of lymph leads to hypoalbuminemia, hyogammaglobulinemia and lymphopenia. Secondary lymphangiectasia occurs secondary to an elevated lymphatic pressure as in lymphoma, systemic lupus erythematosus, constrictive pericarditis, cardiac surgeries (Fontan's procedure), inflammatory bowel disease and malignancies. We, hereby present a five-year-old male child who presented with abdominal distension and poor weight gain. He had hypoalbuminemia, lymphocytopenia and hypogammaglobulinemia. Upper gastrointestinal endoscopy showed normal gastric mucosa and punctate white lesions in duodenal mucosa with biopsy confirming intestinal lymphangiectasia. Secondary causes of intestinal lymphangiectasia were ruled out. Echocardiography revealed atrial septal defect which is an uncommon association with Waldmann's disease. He was started on low fat, high protein diet and medium chain triglyceride supplementation following which he improved symptomatically. High index of suspicion, early diagnosis and appropriate dietary treatment are necessary to alleviate symptoms as well as to achieve a sustainable growth and development in these children.

MRI facilitated a diagnosis of endometriosis of the rectum.

PubMed

Eguchi, S; Komuta, K; Haraguchi, M; Furui, J; Kanematsu, T

2000-01-01

A 51-year-old pre-menopausal Japanese woman suffering from chronic lower abdominal pain was referred to our hospital. A barium enema showed a stenotic lesion in the recto-sigmoid region, and a pelvic computed axial tomography (CAT) scan revealed a thickened rectal wall. A colonoscopic examination showed the rectum to be constrictive, but the mucosa appeared to be intact. Magnetic resonance imaging (MRI) with T1 high-intensity revealed a cystic lesion in the thickened wall of the rectum, which led us to suspect possible bowel endometriosis. Part of the biopsy specimen showed endometrial epithelium within the interstitial layer of histologically normal mucosa; finally, endometriosis of the rectum was diagnosed. The patient became asymptomatic after the initiation of hormonal treatment and later experienced spontaneous menopause. MRI was effective for diagnosis and the patient did not undergo unnecessary laparotomy. Although bowel endometriosis is generally diagnosed by means of resected specimens, in our patient, diagnosis was made using MRI and biopsy, and hormonal therapy had an effective role as a bridge to menopause.

Effects of exercise and Kinesio taping on abdominal recovery in women with cesarean section: a pilot randomized controlled trial.

PubMed

Gürşen, Ceren; İnanoğlu, Deniz; Kaya, Serap; Akbayrak, Türkan; Baltacı, Gül

2016-03-01

Abdominal muscle strength decreases and fat ratio in the waist region increases following cesarean section. Kinesio taping (KT) is an easily applicable method and stimulates muscle activation. The aim of this pilot randomized controlled trial (RCT) was to investigate the effects of KT combined with exercise in women with cesarean section on abdominal recovery compared to the exercise alone. Twenty-four women in between the fourth and sixth postnatal months who had cesarean section were randomly assigned to KT + exercise (n = 12) group or exercise group (n = 12). KT was applied twice a week for 4 weeks on rectus abdominis, oblique abdominal muscles and cesarean incision. All women were instructed to carry out posterior pelvic tilt, core stabilization and abdominal correction exercises. Outcome measures were evaluated with the manual muscle test, sit-up test, abdominal endurance test, Visual Analog Scale (VAS), circumference measurements and Roland Morris Disability Questionnaire (RMDQ). Mann-Whitney U and Wilcoxon tests were used to analyze data. p < 0.05 was considered as statistically significant. The improvement observed in the KT + exercise group was significantly greater compared to the exercise group in terms of the strength of the rectus abdominis muscle, sit-up test, VAS, measurements of the waist circumference and RMDQ (p < 0.05). It appears that the addition of KT to abdominal exercises in the postnatal physiotherapy program provides greater benefit for the abdominal recovery in women with cesarean section. Further studies with larger sample sizes and long-term follow-up are needed to verify these results.

Crucial role of rho-kinase in pressure overload-induced right ventricular hypertrophy and dysfunction in mice.

PubMed

Ikeda, Shohei; Satoh, Kimio; Kikuchi, Nobuhiro; Miyata, Satoshi; Suzuki, Kota; Omura, Junichi; Shimizu, Toru; Kobayashi, Kenta; Kobayashi, Kazuto; Fukumoto, Yoshihiro; Sakata, Yasuhiko; Shimokawa, Hiroaki

2014-06-01

Right ventricular (RV) failure is the leading cause of death in various cardiopulmonary diseases, including pulmonary hypertension. It is generally considered that the RV is vulnerable to pressure overload as compared with the left ventricle (LV). However, as compared with LV failure, the molecular mechanisms of RV failure are poorly understood, and hence therapeutic targets of the disorder remain to be elucidated. Thus, we aimed to identify molecular therapeutic targets for RV failure in a mouse model of pressure overload. To induce pressure overload to respective ventricles, we performed pulmonary artery constriction or transverse aortic constriction in mice. We first performed microarray analysis and found that the molecules related to RhoA/Rho-kinase and integrin pathways were significantly upregulated in the RV with pulmonary artery constriction compared with the LV with transverse aortic constriction. Then, we examined the responses of both ventricles to chronic pressure overload in vivo. We demonstrated that compared with transverse aortic constriction, pulmonary artery constriction caused greater extents of mortality, Rho-kinase expression (especially ROCK2 isoform), and oxidative stress in pressure-overloaded RV, reflecting the weakness of the RV in response to pressure overload. Furthermore, mice with myocardial-specific overexpression of dominant-negative Rho-kinase showed resistance to pressure overload-induced hypertrophy and dysfunction associated with reduced oxidative stress. Finally, dominant-negative Rho-kinase mice showed a significantly improved long-term survival in both pulmonary artery constriction and transverse aortic constriction as compared with littermate controls. These results indicate that the Rho-kinase pathway plays a crucial role in RV hypertrophy and dysfunction, suggesting that the pathway is a novel therapeutic target of RV failure in humans. © 2014 American Heart Association, Inc.

Flow Energy Piezoelectric Bimorph Nozzle Harvester

NASA Technical Reports Server (NTRS)

Walkemeyer, Phillip E. (Inventor); Tosi, Phillipe (Inventor); Corbett, Thomas Gary (Inventor); Hall, Jeffrey L. (Inventor); Lee, Hyeong Jae (Inventor); Arrazola, Alvaro Jose (Inventor); Sherrit, Stewart (Inventor); Colonius, Tim (Inventor); Kim, Namhyo (Inventor); Sun, Kai (Inventor)

2016-01-01

A flow energy harvesting device having a harvester pipe includes a flow inlet that receives flow from a primary pipe, a flow outlet that returns the flow into the primary pipe, and a flow diverter within the harvester pipe having an inlet section coupled to the flow inlet, a flow constriction section coupled to the inlet section and positioned at a midpoint of the harvester pipe and having a spline shape with a substantially reduced flow opening size at a constriction point along the spline shape, and an outlet section coupled to the constriction section. The harvester pipe may further include a piezoelectric structure extending from the inlet section through the constriction section and point such that the fluid flow past the constriction point results in oscillatory pressure amplitude inducing vibrations in the piezoelectric structure sufficient to cause a direct piezoelectric effect and to generate electrical power for harvesting.

Role of Copper and Homocysteine in Pressure Overload Heart Failure

PubMed Central

Hughes, William M.; Rodriguez, Walter E.; Rosenberger, Dorothea; Chen, Jing; Sen, Utpal; Tyagi, Neetu; Moshal, Karni S.; Vacek, Thomas; Kang, Y. James

2009-01-01

Elevated levels of homocysteine (Hcy) (known as hyperhomocysteinemia HHcy) are involved in dilated cardiomyopathy. Hcy chelates copper and impairs copper-dependent enzymes. Copper deficiency has been linked to cardiovascular disease. We tested the hypothesis that copper supplement regresses left ventricular hypertrophy (LVH), fibrosis and endothelial dysfunction in pressure overload DCM mice hearts. The mice were grouped as sham, sham + Cu, aortic constriction (AC), and AC + Cu. Aortic constriction was performed by transverse aortic constriction. The mice were treated with or without 20 mg/kg copper supplement in the diet for 12 weeks. The cardiac function was assessed by echocardiography and electrocardiography. The matrix remodeling was assessed by measuring matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinases (TIMPs), and lysyl oxidase (LOX) by Western blot analyses. The results suggest that in AC mice, cardiac function was improved with copper supplement. TIMP-1 levels decreased in AC and were normalized in AC + Cu. Although MMP-9, TIMP-3, and LOX activity increased in AC and returned to baseline value in AC + Cu, copper supplement showed no significant effect on TIMP-4 activity after pressure overload. In conclusion, our data suggest that copper supplement helps improve cardiac function in a pressure overload dilated cardiomyopathic heart. PMID:18679830

[Permanent constrictions of the jaws (author's transl)].

PubMed

Dupuis, A; Michaud, J

1981-01-01

Permanent constrictions of the jaws are of various types depending on the site of the lesion: temporomaxillary ankylosis, extra-articular constrictions of bone, skin, muscle, or mucosal origin, and those arising from tumors. The commonest cause is injury, those due to infection being currently less frequently observed, which cannot be said for those of tumoral origin. The consequences are difficulty in taking foud and poor buccodental hygiene, while temporomaxillary ankylosis in children provokes mandibular growth disturbances. Surgical treatment is aimed at removing the constriction. Total resection of the ankylosed block is essential to avoid recurrences, while reeducation of buccal opening must be started early and continued for long periods in all cases.

Lipoinjection and Multiple Internal Cuts for Congenital Constriction Bands: A New Treatment Approach.

PubMed

Castro-Govea, Yanko; Vela-Martinez, Amin; Treviño-Garcia, Luis Alberto

2017-04-01

Traditional treatment for a congenital constriction band of the limb involves multiple Z-plasties and W-plasties. We propose an alternative surgical procedure for the treatment of congenital constriction bands that obviates the need for Z-plasties and eliminates the constriction band. We present the case of a 36-year-old woman with a congenital constriction band of the leg. Using a minimally invasive approach, the skin segment that included the band was dissected from the deep tissues. Afterwards, multiple slices were performed on the internal surface of the fibrous ring. This and lipoinjection were used to reverse the depression that characterizes the "hourglass sign" and homogenize the skin surface. Results have remained stable in a follow-up period of 18 months. This surgical alternative can be considered as an option for the treatment of congenital constriction bands. It is a safe, reproducible procedure that does not cause additional scars and has good functional and aesthetic results. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Echocardiography: pericardial thickening and constrictive pericarditis.

PubMed

Schnittger, I; Bowden, R E; Abrams, J; Popp, R L

1978-09-01

A total of 167 patients with pericardial thickening noted on M node echocardiography were studied retrospectively. After the echocardiogram, 72 patients underwent cardiac surgery, cardiac catheterization or autopsy for various heart diseases; 96 patients had none of these procedures. In 49 patients the pericardium was directly visualized at surgery or autopsy; 76 percent of these had pericardial thickening or adhesions. In another 8 percent, pericardial adhesions were absent, but no comment had been made about the appearance of the pericardium itself. In the remaining 16 percent, no comment had been made about the pericardium or percardial space. Cardiac catheterization in 64 patients revealed 24 with hemodynamic findings of constrictive pericarditis or effusive constrictive disease. Seven echocardiographic patterns consistent with pericardial adhesions or pericardial thickening are described and related when possible to the subsequent findings at heart surgery or autopsy. The clinical diagnoses of 167 patients with pericardial thickening are presented. The hemodynamic diagnosis of constrictive pericardial disease was associated with the echocardiographic finding of pericardial thickening, but there were no consistent echocardiographic patterns of pericardial thickening diagnostic of constriction. However, certain other echocardiographic abnormalities of left ventricular posterior wall motion and interventricular septal motion and a high E-Fo slope were suggestive of constriction.

Both cardiomyocyte and endothelial cell Nox4 mediate protection against hemodynamic overload-induced remodelling.

PubMed

Zhang, Min; Mongue-Din, Heloise; Martin, Daniel; Catibog, Norman; Smyrnias, Ioannis; Zhang, Xiaohong; Yu, Bin; Wang, Minshu; Brandes, Ralf P; Schröder, Katrin; Shah, Ajay M

2018-03-01

NADPH oxidase-4 (Nox4) is an important reactive oxygen species (ROS) source that is upregulated in the haemodynamically overloaded heart. Our previous studies using global Nox4 knockout (Nox4KO) mice demonstrated a protective role of Nox4 during chronic abdominal aortic banding, involving a paracrine enhancement of myocardial capillary density. However, other authors who studied cardiac-specific Nox4KO mice reported detrimental effects of Nox4 in response to transverse aortic constriction (TAC). It has been speculated that these divergent results are due to cell-specific actions of Nox4 (i.e. cardiomyocyte Nox4 detrimental but endothelial Nox4 beneficial) and/or differences in the model of pressure overload (i.e. abdominal banding vs. TAC). This study aimed to (i) investigate whether the effects of Nox4 on pressure overload-induced cardiac remodelling vary according to the pressure overload model and (ii) compare the roles of cardiomyocyte vs. endothelial cell Nox4. Global Nox4KO mice subjected to TAC developed worse cardiac remodelling and contractile dysfunction than wild-type littermates, consistent with our previous results with abdominal aortic banding. Next, we generated inducible cardiomyocyte-specific Nox4 KO mice (Cardio-Nox4KO) and endothelial-specific Nox4 KO mice (Endo-Nox4KO) and studied their responses to pressure overload. Both Cardio-Nox4KO and Endo-Nox4KO developed worse pressure overload-induced cardiac remodelling and dysfunction than wild-type littermates, associated with significant decrease in protein levels of HIF1α and VEGF and impairment of myocardial capillarization. Cardiomyocyte as well as endothelial cell Nox4 contributes to protection against chronic hemodynamic overload-induced cardiac remodelling, at least in part through common effects on myocardial capillary density. © The Author 2017 Published by Oxford University Press on behalf of the European Society of Cardiology.

Situs ambiguus in a Brown Swiss cow with polysplenia: case report

PubMed Central

2013-01-01

Background Laterality defects are rare in cattle and usually manifest as asplenia or polysplenia syndrome. These syndromes may be associated with situs ambiguus, which is a dislocation of some but not all internal organs. The objective of this report was to describe the clinical and post-mortem findings including the macroscopic and microscopic anatomy of selected organs in a cow with polysplenia and situs ambiguus. Case presentation A 3.5-year-old Brown Swiss cow was referred to the Department of Farm Animals, Vetsuisse Faculty, University of Zurich, because of poor appetite and recurrent indigestion. A diagnosis of situs ambiguus was based on the results of physical examination, ultrasonography, exploratory laparotomy and post-mortem examination. The latter revealed that the rumen was on the right side and lacked compartmentalisation. There were two spleens, one on the left (26.5 x 12.0 cm) and one on the right (20.5 x 5.5 cm), and the omasum was located craniolateral to the ruminoreticulum on the left. The abomasum was located on the right, although it had initially been displaced to the left. The three-lobed liver occupied the left and central cranioventral aspect of the abdominal cavity (cavum abdominis). Only the right and left hepatic veins (vena hepatica dextra and sinistra) drained into the thoracic segment of the caudal vena cava (vena cava caudalis), and histological changes in the liver were indicative of impaired haemodynamics. The mesojejunum was not fused with the mesentery of the spiral loop (ansa spiralis) of the ascending colon (colon ascendens). The latter was folded and the transverse colon (colon transversum) ran caudal to the cranial mesenteric artery (arteria mesenteria cranialis). Fibrotic constrictions were seen in the lumen of the caecum and proximal loop (ansa proximalis) of the ascending colon. Both kidneys were positioned retroperitoneally in a lumbar position. The lumbar segment of the caudal vena cava did not descend to the liver and instead drained into the right azygous vein (vena azygos dextra). Conclusions Recurrent digestive problems and poor production in this patient may have been caused by a lack of rumen compartmentalisation, abnormal abomasal motility, constrictions in the large intestine (intestinum crassum) and fibrosis of the liver. The abomasum had abnormal motility most likely because it was anchored inadequately and only at its cranial aspect to the liver by the lesser omentum (omentum minus) and to the dorsal abdominal wall and rumen by a short greater omentum (omentum majus). PMID:23421814

Electromyographic and kinetic analysis of two abdominal muscle performance tests.

PubMed

Haladay, Douglas E; Denegar, Craig R; Miller, Sayers J; Challis, John

2015-01-01

In order to accurately assess the abdominal muscles, clinicians need valid clinical measures. The double leg lowering test (DLLT) and lower abdominal muscle progression (LAMP) are two common tests of abdominal muscle performance. The purposes of this study were to determine the relation between surface electromyographic (EMG) activity during the DLLT and LAMP levels; hip joint resultant moments and DLLT and LAMP levels; and the two measures of DLLT and LAMP. Ten healthy participants were tested under both conditions. Surface EMG activity of the abdominal muscles was obtained, while pelvic movement was detected simultaneously. A moderate to strong association was found between rectus abdominus muscle activity and a moderate association with the external obliques with both test levels. For the internal oblique/transversus abdominus, a moderate and weak association was found with the DLLT and LAMP, respectively. A very strong association existed between the hip resultant joint moments (RJM) and the DLLT, while there was a weak correlation between hip RJM and the LAMP. No significant correlation was found between the DLLT and LAMP grades. This finding suggests that these tests may measure different qualities of muscle performance and provides preliminary support for their use. Further evaluation of these assessments with clinical populations is necessary.

Reproducibility of abdominal fat assessment by ultrasound and computed tomography

PubMed Central

Mauad, Fernando Marum; Chagas-Neto, Francisco Abaeté; Benedeti, Augusto César Garcia Saab; Nogueira-Barbosa, Marcello Henrique; Muglia, Valdair Francisco; Carneiro, Antonio Adilton Oliveira; Muller, Enrico Mattana; Elias Junior, Jorge

2017-01-01

Objective: To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments. Materials and Methods: Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the anthropometric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT. Results: Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71. Conclusion: In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility. PMID:28670024

Reproducibility of abdominal fat assessment by ultrasound and computed tomography.

PubMed

Mauad, Fernando Marum; Chagas-Neto, Francisco Abaeté; Benedeti, Augusto César Garcia Saab; Nogueira-Barbosa, Marcello Henrique; Muglia, Valdair Francisco; Carneiro, Antonio Adilton Oliveira; Muller, Enrico Mattana; Elias Junior, Jorge

2017-01-01

To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments. Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the anthropometric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT. Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71. In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility.

Endophyte-infected tall fescue seed extract induces constriction of bovine vasculature

USDA-ARS?s Scientific Manuscript database

Ergovaline (ERV) has been extensively used to study vasoactive effects of endophyte (Neotyphodium coenophialum) infected tall fescue (Lolium arundinaceum). However preliminary in vitro tests show that an extract of toxic tall fescue seed (E+EXT) is more potent than ERV alone indicating other compoun...

Scour at bridge sites in Delaware, Maryland, and Virginia

USGS Publications Warehouse

Hayes, Donald C.

1996-01-01

Scour data were obtained from discharge measure- ments to develop and evaluate the reliability of constriction-scour and local-scour equations for rivers in Delaware, Maryland, and Virginia. No independent constriction-scour or local-scour equations were developed from the data because no significant relation was deter-mined between measured scour and streamflow, streambed, and bridge characteristics. Two existing equations were evaluated for prediction of constriction scour and 14 existing equations were evaluated for prediction of local scour. Constriction-scour data were obtained from historical stream discharge measurements, field surveys, and bridge plans at nine bridge sites in the three-State area. Constriction scour was computed by subtracting the average-streambed elevation in the constricted reach from an uncontracted-channel reference elevation. Hydraulic conditions were estimated for the measurements with the greatest discharges by use of the Water-Surface Profile computation model. Measured and calculated constriction-scour data were used to evaluate the reliability of Laursen's clear-water constriction-scour equation and Laursen's live-bed constriction-scour equation. Laursen's clear-water constriction-scour equation underestimated 21 of 23 scour measure- ments made at three sites. A sensitivity analysis showed that the equation is extremely sensitive to estimates of the channel-bottom width. Reduction in estimates of bottom width by one-third resulted in predictions of constriction scour slightly greater than measured values for all scour measurements. Laursen's live-bed constriction- scour equation underestimated 10 of 14 scour measurements made at one site. The error between measured and predicted constriction scour was less than 1.0 ft (feet) for 12 measure-ments and less than 0.5 ft for 8 measurements. Local-scour data were obtained from stream discharge measurements, field surveys, and bridge plans at 15 bridge sites in the three-State area. The reliability of 14 local-scour equations were evaluated. From visual inspection of the plotted data, the Colorado State University, Froehlich design, Laursen, and Mississippi pier-scour equations appeared to be the best predictors of local scour. The Colorado State University equation underestimated 11 scour depths in clear-water scour conditions by a maximum of 2.4 ft, and underestimated 3 scour depth in live-bed scour conditions by a maximum of 1.3 ft. The Froehlich design equation under- estimated two scour depth in clear-water scour conditions by a maximum of 1.2 ft, and under- estimated one scour depth in live-bed scour conditions by a maximum of 0.4 ft. Laursen's equation overestimated the maximum scour depth in clear-water scour conditions by approximately one-half pier width or approximately 1.5 ft, and overestimated the maximum scour depth in live-bed scour conditions by approximately one-pier width or approximately 3 ft. The Mississippi equation underestimated six scour depths in clear-water scour conditions by a maximum of 1.2 ft, and underestimated one scour depth in live-bed scour conditions by 1.6 ft. In both clear-water and live-bed scour conditions, the upper limit for the depth of scour to pier-width ratio for all local scour measurements was 2.1. An accurate pier- approach velocity is necessary to use many local pier-scour equations for bridge design. Velocity data from all the discharge measurements reviewed for this investigation were used to develop a design curve to estimate pier-approach velocity from mean cross-sectional velocity. A least- squares regression and offset were used to envelop the velocity data.

Antinociceptive effectiveness of Tithonia tubaeformis in a vincristine model of chemotherapy-induced painful neuropathy in mice.

PubMed

Nawaz, Noor Ul Ain; Saeed, Muhammad; Rauf, Khalid; Usman, Muhammad; Arif, Mehreen; Ullah, Zaki; Raziq, Naila

2018-04-25

Chemotherapy induced peripheral neuropathy (CIPN) is a painful side-effect of commonly used chemotherapeutic agents that profoundly impair the quality of life of patients as the current pharmacotherapeutic strategies are inefficient in providing adequate pain relief. Complementary and alternative medicine (CAM) therapies are preferred by patients with neuropathic pain as they experience insufficient control of pain with conventional medications. This study describes the antinociceptive effect of Tithonia tubaeformis (Jacq.) Cass. in a vincristine mouse model of established CIPN. Tithonia tubaeformis hydromethanolic extract was tested for preliminary qualitative phytochemical analysis and acute oral toxicity test in mice. The antinociceptive effect was investigated using the abdominal constriction (writhing) and tail immersion tests (25-200 mg/kg). The anti-neuropathic effect was determined in the vincristine mouse model, established by daily administration of vincristine (0.1 mg/kg/day, i.p) for consecutive 14 days. Acute treatment with Tithonia tubaeformis (100 and 200 mg/kg) and the positive control, gabapentin (75 mg/kg) was carried out on the 15th day of the last vincrsitine dose and the animals were tested for allodynia and thermal hyperalgesia at 30-120 min post extract/drug administration. Vincristine produced significant temporal tactile allodynia and thermal hyperalgesia (P < 0.01 and P < 0.001 on day 7 and 14) and was maintained for the subsequent day (P < 0.001 during 30-120 min). Tithonia tubaeformis was effective in attenuating the vincristine-induced allodynia and thermal hyperalgesia at 100 mg/kg (P < 0.05, P < 0.01) and 200 mg/kg (P < 0.01, P < 0.001). Similarly, gabapentin also showed a robust antinociceptive effect in counteracting the vincristine associated behavioral alterations. Tithonia tubaeformis can be an effective CAM therapeutic remedy for established CIPN due to its potential antinociceptive effect in attenuating vincristine-induced neuropathy. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Shooting quasiparticles from Andreev bound states in a superconducting constriction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riwar, R.-P.; Houzet, M.; Meyer, J. S.

2014-12-15

A few-channel superconducting constriction provides a set of discrete Andreev bound states that may be populated with quasiparticles. Motivated by recent experimental research, we study the processes in an a.c. driven constriction whereby a quasiparticle is promoted to the delocalized states outside the superconducting gap and flies away. We distinguish two processes of this kind. In the process of ionization, a quasiparticle present in the Andreev bound state is transferred to the delocalized states leaving the constriction. The refill process involves two quasiparticles: one flies away while another one appears in the Andreev bound state. We notice an interesting asymmetrymore » of these processes. The electron-like quasiparticles are predominantly emitted to one side of the constriction while the hole-like ones are emitted to the other side. This produces a charge imbalance of accumulated quasiparticles, that is opposite on opposite sides of the junction. The imbalance may be detected with a tunnel contact to a normal metal lead.« less

Analgesic effect of piracetam on peripheral neuropathic pain induced by chronic constriction injury of sciatic nerve in rats.

PubMed

Mehta, Ashish K; Bhati, Yogendra; Tripathi, Chakra D; Sharma, Krishna K

2014-08-01

Despite immense advances in the treatment strategies, management of neuropathic pain remains unsatisfactory. Piracetam is a prototype of nootropic drugs, used to improve cognitive impairment. The present study was designed to investigate the effect of piracetam on peripheral neuropathic pain in rats. Neuropathic pain was induced by the chronic constriction injury of the sciatic nerve. Following this, piracetam was intraperitoneally administered for 2 weeks in doses of 50, 100 and 200 mg/kg, and pain was assessed by employing the behavioural tests for thermal hyperalgesia (hot plate and tail flick tests) and cold allodynia (acetone test). After the induction of neuropathic pain, significant development of thermal hyperalgesia and cold allodynia was observed. The administration of piracetam (50 mg/kg) did not have any significant effect on all the behavioural tests. Further, piracetam (100 mg/kg) also had no effect on the hot plate and tail flick tests; however it significantly decreased the paw withdrawal duration in the acetone test. Piracetam in a dose of 200 mg/kg significantly modulated neuropathic pain as observed from the increased hot plate and tail flick latencies, and decreased paw withdrawal duration (in acetone test). Therefore, the present study suggests the potential use of piracetam in the treatment of neuropathic pain, which merits further clinical investigation.

Role of cardiac output and the autonomic nervous system in the antinatriuretic response to acute constriction of the thoracic superior vena cava.

NASA Technical Reports Server (NTRS)

Schrier, R. W.; Humphreys, M. H.; Ufferman, R. C.

1971-01-01

Study of the differential characteristics of hepatic congestion and decreased cardiac output in terms of potential afferent stimuli in the antinatriuretic effect of acute thoracic inferior vena cava (TIVC) constriction. An attempt is made to see if the autonomic nervous system is involved in the antinatriuretic effect of acute TIVC or thoracic superior vena cava constriction.

Multiplexed fluidic plunger mechanism for the measurement of red blood cell deformability.

PubMed

Myrand-Lapierre, Marie-Eve; Deng, Xiaoyan; Ang, Richard R; Matthews, Kerryn; Santoso, Aline T; Ma, Hongshen

2015-01-07

The extraordinary deformability of red blood cells gives them the ability to repeatedly transit through the microvasculature of the human body. The loss of this capability is part of the pathology of a wide range of diseases including malaria, hemoglobinopathies, and micronutrient deficiencies. We report on a technique for multiplexed measurements of the pressure required to deform individual red blood cell through micrometer-scale constrictions. This measurement is performed by first infusing single red blood cells into a parallel array of ~1.7 μm funnel-shaped constrictions. Next, a saw-tooth pressure waveform is applied across the constrictions to squeeze each cell through its constriction. The threshold deformation pressure is then determined by relating the pressure-time data with the video of the deformation process. Our key innovation is a self-compensating fluidic network that ensures identical pressures are applied to each cell regardless of its position, as well as the presence of cells in neighboring constrictions. These characteristics ensure the consistency of the measurement process and robustness against blockages of the constrictions by rigid cells and debris. We evaluate this technique using in vitro cultures of RBCs infected with P. falciparum, the parasite that causes malaria, to demonstrate the ability to profile the deformability signature of a heterogeneous sample.

Constriction of isolated collecting lymphatic vessels in response to acute increases in downstream pressure

PubMed Central

Scallan, Joshua P; Wolpers, John H; Davis, Michael J

2013-01-01

Collecting lymphatic vessels generate pressure to transport lymph downstream to the subclavian vein against a significant pressure head. To investigate their response to elevated downstream pressure, collecting lymphatic vessels containing one valve (incomplete lymphangion) or two valves (complete lymphangion) were isolated from the rat mesentery and tied to glass cannulae capable of independent pressure control. Downstream pressure was selectively raised to various levels, either stepwise or ramp-wise, while keeping upstream pressure constant. Diameter and valve positions were tracked under video microscopy, while intralymphangion pressure was measured concurrently with a servo-null micropipette. Surprisingly, a potent lymphatic constriction occurred in response to the downstream pressure gradient due to (1) a pressure-dependent myogenic constriction and (2) a frequency-dependent decrease in diastolic diameter. The myogenic index of the lymphatic constriction (−3.3 ± 0.6, in mmHg) was greater than that of arterioles or collecting lymphatic vessels exposed to uniform increases in pressure (i.e. upstream and downstream pressures raised together). Additionally, the constriction was transmitted to the upstream lymphatic vessel segment even though it was protected from changes in pressure by a closed intraluminal valve; the conducted constriction was blocked by loading only the pressurized half of the vessel with either ML-7 (0.5 mm) to block contraction, or cromakalim (3 μm) to hyperpolarize the downstream muscle layer. Finally, we provide evidence that the lymphatic constriction is important to maintain normal intraluminal valve closure during each contraction cycle in the face of an adverse pressure gradient, which probably protects the lymphatic capillaries from lymph backflow. PMID:23045335

Pericarditis - constrictive

MedlinePlus

Constrictive pericarditis is long-term (chronic) inflammation of the sac-like covering of the heart (the pericardium) with thickening and scarring. Related conditions include: Bacterial pericarditis Pericarditis Pericarditis ...

Phytochemical Composition and Antinociceptive Activity of Bauhinia glauca subsp. hupehana in Rats

PubMed Central

Xu, Jinlong; Zhao, Qizhi; Wei, Lei; Yang, Yu; Xu, Rui; Yu, Nengjiang; Zhao, Yimin

2015-01-01

In traditional medicine, Bauhinia glauca subsp. hupehana has long been used as an analgesic agent in China. The aim of this study was to evaluate the antinociceptive activity of the ethanol extract of the aerial parts of B. glauca subsp. hupehana (BHE) in rats and its chemical fingerprint. The antinociceptive activity of BHE was assessed in mice using chemically and heat–induced pain models, such as the acetic acid–induced writhing, hot plate, tail–flick and glutamate tests. Naltrexone hydrochloride, a non–selective opioid receptor antagonist, was utilized to determine the involvement of the opioid system. In addition to this, the involvements of the cGMP and ATP–sensitive K+ channel pathways were also detected using methylene blue and glibenclamide. The oral administration of BHE (at doses of 50, 100 and 200 mg/kg) produced significant and dose–related inhibitions in both the chemically and heat–induced pain models. Interestingly, in the abdominal constriction test, when the dose of BHE was increased to 800 mg/kg (p.o., n = 10), the inhibition rate was 100%. The antinociceptive mechanism may involve the cGMP pathway and ATP sensitive K+ channel pathway. The central antinociceptive effect was not antagonized by naltrexone. One phenolic acid, one lignin and five flavonoids were isolated from BHE. The antinociceptive activity of BHE was most likely due to the presence of the flavonoids. The acute toxicity results showed that BHE was safe at a high dose (2 g/kg, p.o.). The current investigation demonstrates that B. glauca subsp. hupehana is a potential candidate for the development of novel, non–opioid, analgesic phytomedicines. PMID:25658740

Analgesic and anti-inflammatory effects of Mangifera indica L. extract (Vimang).

PubMed

Garrido, G; González, D; Delporte, C; Backhouse, N; Quintero, G; Núñez-Sellés, A J; Morales, M A

2001-02-01

Vimang is an aqueous extract of Mangifera indica used in Cuba to improve the quality of life in patients suffering from elevated stress. To assess its possible analgesic and antiinflammatory effects, the results of a standard extract evaluation are presented. Analgesia was determined using acetic acid-induced abdominal constriction and formalin-induced licking. Antiinflammatory effects were evaluated using carrageenan- and formalin-induced oedema. Vimang (50-1000 mg/kg, p.o.) exhibited a potent and dose-dependent antinociceptive effect against acetic acid test in mice. The mean potency (DE(50)) was 54.5 mg/kg and the maximal inhibition attained was 94.4%. Vimang (20-1000 mg/kg, p.o.) dose-dependently inhibited the second phase of formalin-induced pain but not the first phase. The DE(50) of the second phase was 8.4 mg/kg and the maximal inhibition was 99.5%, being more potent than indomethacin at doses of 20 mg/kg. Vimang (20-1000 mg/kg, p.o.) significantly inhibited oedema formation (p < 0.01 or p < 0.05) of both carrageenan- and formalin-induced oedema in rat, guinea-pigs and mice (maximal inhibitions: 39.5, 45.0 and 48.6, respectively). The inhibitions were similar to those produced by indomethacin and sodium naproxen, p.o. The different polyphenols found in Vimang could account for the antinociceptive and antiinflammatory actions reported here for the first time for M. indica bark aqueous extract. Copyright 2001 John Wiley & Sons, Ltd.

c-Myc alters substrate utilization and O-GlcNAc protein posttranslational modifications without altering cardiac function during early aortic constriction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ledee, Dolena; Smith, Lincoln; Bruce, Margaret

Pressure overload cardiac hypertrophy alters substrate metabolism. Prior work showed that myocardial inactivation of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we hypothesize that Myc regulates substrate preferences for the citric acid cycle during pressure overload hypertrophy from transverse aortic constriction (TAC) and that these metabolic changes impact cardiac function and growth. To test this hypothesis, we subjected mice with cardiac specific, inducible Myc inactivation (MycKO-TAC) and non-transgenic littermates (Cont-TAC) to transverse aortic constriction (TAC; n=7/group). A separate group underwent sham surgery (Sham, n=5). After two weeks, function was measured in isolated workingmore » hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. Compared to Sham, Cont-TAC had increased free fatty acid fractional contribution with a concurrent decrease in unlabeled (predominately glucose) contribution. The changes in free fatty acid and unlabeled fractional contributions were abrogated by Myc inactivation during TAC (MycKO-TAC). Additionally, protein posttranslational modification by O-GlcNAc was significantly greater in Cont-TAC versus both Sham and MycKO-TAC. Lastly, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy.« less

c-Myc alters substrate utilization and O-GlcNAc protein posttranslational modifications without altering cardiac function during early aortic constriction

DOE PAGES

Ledee, Dolena; Smith, Lincoln; Bruce, Margaret; ...

2015-08-12

Pressure overload cardiac hypertrophy alters substrate metabolism. Prior work showed that myocardial inactivation of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we hypothesize that Myc regulates substrate preferences for the citric acid cycle during pressure overload hypertrophy from transverse aortic constriction (TAC) and that these metabolic changes impact cardiac function and growth. To test this hypothesis, we subjected mice with cardiac specific, inducible Myc inactivation (MycKO-TAC) and non-transgenic littermates (Cont-TAC) to transverse aortic constriction (TAC; n=7/group). A separate group underwent sham surgery (Sham, n=5). After two weeks, function was measured in isolated workingmore » hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. Compared to Sham, Cont-TAC had increased free fatty acid fractional contribution with a concurrent decrease in unlabeled (predominately glucose) contribution. The changes in free fatty acid and unlabeled fractional contributions were abrogated by Myc inactivation during TAC (MycKO-TAC). Additionally, protein posttranslational modification by O-GlcNAc was significantly greater in Cont-TAC versus both Sham and MycKO-TAC. Lastly, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy.« less

Retrospective comparison of abdominal ultrasonography and radiography in the investigation of feline abdominal disease

PubMed Central

Won, Wylen Wade; Sharma, Ajay; Wu, Wenbo

2015-01-01

Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This retrospective study compared the clinical usefulness of abdominal radiography and ultrasonography in 105 feline patients with signs of abdominal disease. The final diagnosis was determined more commonly with ultrasonography (59%) compared to radiography (25.7%). Ultrasonography was also able to provide additional clinically relevant information in 76% of cases, and changed or refined the diagnosis in 47% of cases. Based on these findings, ultrasonography may be sufficient as an initial diagnostic test for the investigation of feline abdominal disease. PMID:26483582

Does relative out-group size in neighborhoods drive down associational life of Whites in the U.S.? Testing constrict, conflict and contact theories.

PubMed

Savelkoul, Michael; Hewstone, Miles; Scheepers, Peer; Stolle, Dietlind

2015-07-01

We test whether a larger percentage of non-Whites in neighborhoods decreases associational involvement and build on earlier research in three ways. First, we explicitly consider the ethnic composition of organizations, distinguishing involvement in bridging (with out-group members) and bonding (only in-group members) organizations. Second, we start from constrict theory and test competing sets of predictions derived from conflict and contact theories to explain these relationships. Third, we examine whether relative out-group size affects involvement in different types of voluntary organizations equally. Using data from the 2005 U.S. 'Citizenship, Involvement, Democracy' survey, the percentage of non-Whites in neighborhoods is largely unrelated with associational involvement or perceived ethnic threat. However, perceiving ethnic threat is consistently negatively related with involvement in bridging organizations. Simultaneously, a larger percentage of non-Whites fosters intergroup contact, which is negatively related with perceptions of ethnic threat and involvement in bonding leisure organizations. Our results shed more light on the relationship between the relative out-group size in neighborhoods and associational involvement as well as underlying explanations for this link. Copyright © 2015 Elsevier Inc. All rights reserved.

Minimally Invasive Transverse Aortic Constriction in Mice.

PubMed

Zaw, Aung Moe; Williams, Connor M; Law, Helen K W; Chow, Billy Kwok Chong

2017-03-14

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard open-chest transverse aortic constriction (TAC). Although transverse aortic constriction is a highly functional method for the induction of high pressure in the left ventricle, it is a more difficult and lengthy procedure due to its use of artificial ventilation with tracheal intubation. TAC is oftentimes also less survivable, as the newer method, MTAC, neither requires the cutting of the ribs and intercostal muscles nor tracheal intubation with a ventilation setup. In MTAC, as opposed to a thoracotomy to access to the chest cavity, the aortic arch is reached through a midline incision in the anterior neck. The thyroid is pulled back to reveal the sternal notch. The sternum is subsequently cut down to the second rib level, and the aortic arch is reached simply by separating the connective tissues and thymus. From there, a suture can be wrapped around the arch and tied with a spacer, and then the sternal cut and skin can be closed. MTAC is a much faster and less invasive way to induce left ventricular hypertension and enables the possibility for high-throughput studies. The success of the constriction can be verified using high-frequency trans-thoracic echocardiography, particularly color Doppler and pulsed-wave Doppler, to determine the flow velocities of the aortic arch and left and right carotid arteries, the dimension of the blood vessels, and the left ventricular function and morphology. A successful constriction will also trigger significant histopathological changes, such as cardiac muscle cell hypertrophy with interstitial and perivascular fibrosis. Here, the procedure of MTAC is described, demonstrating how the resulting flow changes in the carotid arteries can be examined with echocardiography, gross morphology, and histopathological changes in the heart.

Chemical substitutions in the selectivity filter of potassium channels do not rule out constricted-like conformations for C-type inactivation

PubMed Central

Li, Jing; Boulanger, Eliot; Rui, Huan; Perozo, Eduardo; Roux, Benoît

2017-01-01

In many K+ channels, prolonged activating stimuli lead to a time-dependent reduction in ion conduction, a phenomenon known as C-type inactivation. X-ray structures of the KcsA channel suggest that this inactivated state corresponds to a “constricted” conformation of the selectivity filter. However, the functional significance of the constricted conformation has become a matter of debate. Functional and structural studies based on chemically modified semisynthetic KcsA channels along the selectivity filter led to the conclusion that the constricted conformation does not correspond to the C-type inactivated state. The main results supporting this view include the observation that C-type inactivation is not suppressed by a substitution of D-alanine at Gly77, even though this modification is believed to lock the selectivity filter into its conductive conformation, whereas it is suppressed following amide-to-ester backbone substitutions at Gly77 and Tyr78, even though these structure-conserving modifications are not believed to prevent the selectivity filter from adopting the constricted conformation. However, several untested assumptions about the structural and functional impact of these chemical modifications underlie these arguments. To make progress, molecular dynamics simulations based on atomic models of the KcsA channel were performed. The computational results support the notion that the constricted conformation of the selectivity filter corresponds to the functional C-type inactivated state of the KcsA. Importantly, MD simulations reveal that the semisynthetic KcsAD-ala77 channel can adopt an asymmetrical constricted-like nonconductive conformation and that the amide-to-ester backbone substitutions at Gly77 and Tyr78 perturb the hydrogen bonding involving the buried water molecules stabilizing the constricted conformation. PMID:28973956

Can breathing-like pressure oscillations reverse or prevent narrowing of small intact airways?

PubMed

Harvey, Brian C; Parameswaran, Harikrishnan; Lutchen, Kenneth R

2015-07-01

Periodic length fluctuations of airway smooth muscle during breathing are thought to modulate airway responsiveness in vivo. Recent animal and human intact airway studies have shown that pressure fluctuations simulating breathing can only marginally reverse airway narrowing and are ineffective at protecting against future narrowing. However, these previous studies were performed on relatively large (>5 mm diameter) airways, which are inherently stiffer than smaller airways for which a preponderance of airway constriction in asthma likely occurs. The goal of this study was to determine the effectiveness of breathing-like transmural pressure oscillations to reverse induced narrowing and/or protect against future narrowing of smaller, more compliant intact airways. We constricted smaller (luminal diameter = 2.92 ± 0.29 mm) intact airway segments twice with ACh (10(-6) M), once while applying tidal-like pressure oscillations (5-15 cmH2O) before, during, and after inducing constriction (Pre + Post) and again while only imposing the tidal-like pressure oscillation after induced constriction (Post Only). Smaller airways were 128% more compliant than previously studied larger airways. This increased compliance translated into 196% more strain and 76% greater recovery (41 vs. 23%) because of tidal-like pressure oscillations. Larger pressure oscillations (5-25 cmH2O) caused more recovery (77.5 ± 16.5%). However, pressure oscillations applied before and during constriction resulted in the same steady-state diameter as when pressure oscillations were only applied after constriction. These data show that reduced straining of the airways before a challenge likely does not contribute to the emergence of airway hyperreactivity observed in asthma but may serve to sustain a given level of constriction. Copyright © 2015 the American Physiological Society.

Numerical Simulation of Passage of a Neutrophil through a Rectangular Channel with a Moderate Constriction

PubMed Central

Shirai, Atsushi; Masuda, Sunao

2013-01-01

The authors have previously presented a mathematical model to predict transit time of a neutrophil through an alveolar capillary segment which was modeled as an axisymmetric arc-shaped constriction settled in a cylindrical straight pipe to investigate the influence of entrance curvature of a capillary on passage of the cell. The axially asymmetric cross section of a capillary also influences the transit time because it requires three-dimensional deformation of a cell when it passes through the capillary and could lead to plasma leakage between the cell surface and the capillary wall. In this study, a rectangular channel was introduced, the side walls of which were moderately constricted, as a representative of axially asymmetric capillaries. Dependence of transit time of a neutrophil passing through the constriction on the constriction geometry, i.e., channel height, throat width and curvature radius of the constriction, was numerically investigated, the transit time being compared with that through the axisymmetric model. It was found that the transit time is dominated by the throat hydraulic diameter and curvature radius of the constriction and that the throat aspect ratio little affects the transit time with a certain limitation, indicating that if an appropriate curvature radius is chosen, such a rectangular channel model can be substituted for an axisymmetric capillary model having the same throat hydraulic diameter in terms of the transit time by choosing an appropriate curvature radius. Thus, microchannels fabricated by the photolithography technique, whose cross section is generally rectangular, are expected to be applicable to in vitro model experiments of neutrophil retention and passage in the alveolar capillaries. PMID:23527190

Toward Defining "Vocal Constriction": Practitioner Perspectives.

PubMed

Lemon-McMahon, Belinda; Hughes, Diane

2018-01-01

This research investigated the terminology used in relation to constriction of the singing voice from a range of practitioner perspectives. It focused on the locality, causes, consequences, management, trends, identification, and vocabulary of constriction. The research aimed to develop a holistic understanding of the term "vocal constriction" from participant experiences and perceptions (N = 10). Data collection occurred through in-depth, semi-structured interviews with a range of voice care professionals. Participants included three professional groups: (1) Ear, Nose, and Throat medical specialists or laryngologists, (2) speech pathologists or speech therapists, and (3) singing teachers. Purposive sampling was used to ensure that the participants from groups 1 and 2 had extensive experience with singers in their practice. The singing teachers were experienced in either classical or contemporary styles, or both. Participant responses highlighted a discrepancy in preferred terminology, with "constriction" being less favored overall. Several anatomical locations were identified including postural, supraglottic (anteroposterior and false fold), articulatory, and in the intrinsic and extrinsic laryngeal musculature; psychological issues were also identified. Primary causes, secondary causes, and influencing factors were identified. Inefficient technique and poor posture or alignment were considered primary causes; similarly, emotion and anxiety or stress were identified as influencing factors by the majority of participants. There was less uniformity in responses regarding other causes. The major findings of this research are the respective participant group distinctions, an uncertainty regarding anteroposterior constriction, and that the location and effects of constriction are individual to the singer and must be considered contextually. A definition is offered, and areas for further research are identified. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

A groundwater convection model for Rio Grande rift geothermal resources

NASA Technical Reports Server (NTRS)

Morgan, P.; Harder, V.; Daggett, P. H.; Swanberg, C. A.

1981-01-01

It has been proposed that forced convection, driven by normal groundwater flow through the interconnected basins of the Rio Grande rift is the primary source mechanism for the numerous geothermal anomalies along the rift. A test of this concept using an analytical model indicates that significant forced convection must occur in the basins even if permeabilities are as low as 50-200 millidarcies at a depth of 2 km. Where groundwater flow is constricted at the discharge areas of the basins forced convection can locally increase the gradient to a level where free convection also occurs, generating surface heat flow anomalies 5-15 times background. A compilation of groundwater data for the rift basins shows a strong correlation between constrictions in groundwater flow and hot springs and geothermal anomalies, giving strong circumstantial support to the convection model.

Visual training improves underwater vision in children.

PubMed

Gislén, Anna; Warrant, Eric J; Dacke, Marie; Kröger, Ronald H H

2006-10-01

Children in a tribe of sea-gypsies from South-East Asia have been found to have superior underwater vision compared to European children. In this study, we show that the improved underwater vision of these Moken children is not due to better contrast sensitivity in general. We also show that European children can achieve the same underwater acuity as the Moken children. After 1 month of underwater training (11 sessions) followed by 4 months with no underwater activities, European children showed improved underwater vision and distinct bursts of pupil constriction. When tested 8 months after the last training session in an outdoor pool in bright sunlight-comparable to light environments in South-East Asia-the children had attained the same underwater acuity as the sea-gypsy children. The achieved performance can be explained by the combined effect of pupil constriction and strong accommodation.

Isolated cortical visual loss with subtle brain MRI abnormalities in a case of hypoxic-ischemic encephalopathy.

PubMed

Margolin, Edward; Gujar, Sachin K; Trobe, Jonathan D

2007-12-01

A 16-year-old boy who was briefly asystolic and hypotensive after a motor vehicle accident complained of abnormal vision after recovering consciousness. Visual acuity was normal, but visual fields were severely constricted without clear hemianopic features. The ophthalmic examination was otherwise normal. Brain MRI performed 11 days after the accident showed no pertinent abnormalities. At 6 months after the event, brain MRI demonstrated brain volume loss in the primary visual cortex and no other abnormalities. One year later, visual fields remained severely constricted; neurologic examination, including formal neuropsychometric testing, was normal. This case emphasizes the fact that hypoxic-ischemic encephalopathy (HIE) may cause enduring damage limited to primary visual cortex and that the MRI abnormalities may be subtle. These phenomena should be recognized in the management of patients with HIE.

Wall shear stress estimates in coronary artery constrictions

NASA Technical Reports Server (NTRS)

Back, L. H.; Crawford, D. W.

1992-01-01

Wall shear stress estimates from laminar boundary layer theory were found to agree fairly well with the magnitude of shear stress levels along coronary artery constrictions obtained from solutions of the Navier Stokes equations for both steady and pulsatile flow. The relatively simple method can be used for in vivo estimates of wall shear stress in constrictions by using a vessel shape function determined from a coronary angiogram, along with a knowledge of the flow rate.

Annual Research Progress Report Fiscal Year 1987. Volume 1,

DTIC Science & Technology

1987-10-01

Constrictive Pericarditis 86 in Patients. (0) C-20-85 Pressure Waveforms and Reflections in the Human Aorta: Compari- 87 son of a Cadaver Model with In...in Constrictive 125 Pericarditis . (0) C-60-86 The Natural History of HTLV-III Infection and Disease in a 126 United States Military Population. (0...Sheet Date: 18 Mar 87 Proj No: C-16-85 Status: Terminated Title: Significance of Post Radiotherapy Constrictive Pericarditis in Patients. Start Date 21

Timely Endocytosis of Cytokinetic Enzymes Prevents Premature Spindle Breakage during Mitotic Exit

PubMed Central

Onishi, Masayuki; Yeong, Foong May

2016-01-01

Cytokinesis requires the spatio-temporal coordination of membrane deposition and primary septum (PS) formation at the division site to drive acto-myosin ring (AMR) constriction. It has been demonstrated that AMR constriction invariably occurs only after the mitotic spindle disassembly. It has also been established that Chitin Synthase II (Chs2p) neck localization precedes mitotic spindle disassembly during mitotic exit. As AMR constriction depends upon PS formation, the question arises as to how chitin deposition is regulated so as to prevent premature AMR constriction and mitotic spindle breakage. In this study, we propose that cells regulate the coordination between spindle disassembly and AMR constriction via timely endocytosis of cytokinetic enzymes, Chs2p, Chs3p, and Fks1p. Inhibition of endocytosis leads to over accumulation of cytokinetic enzymes during mitotic exit, which accelerates the constriction of the AMR, and causes spindle breakage that eventually could contribute to monopolar spindle formation in the subsequent round of cell division. Intriguingly, the mitotic spindle breakage observed in endocytosis mutants can be rescued either by deleting or inhibiting the activities of, CHS2, CHS3 and FKS1, which are involved in septum formation. The findings from our study highlight the importance of timely endocytosis of cytokinetic enzymes at the division site in safeguarding mitotic spindle integrity during mitotic exit. PMID:27447488

MRCK-1 drives apical constriction in C. elegans by linking developmental patterning to force generation

PubMed Central

Marston, Daniel J.; Higgins, Christopher D.; Peters, Kimberly A.; Cupp, Timothy D.; Dickinson, Daniel J.; Pani, Ariel M.; Moore, Regan P.; Cox, Amanda H.; Kiehart, Daniel P.; Goldstein, Bob

2016-01-01

Summary Apical constriction is a change in cell shape that drives key morphogenetic events including gastrulation and neural tube formation. Apical force-producing actomyosin networks drive apical constriction by contracting while connected to cell-cell junctions. The mechanisms by which developmental patterning regulates these actomyosin networks and associated junctions with spatial precision are not fully understood. Here, we identify a myosin light chain kinase MRCK-1 as a key regulator of C. elegans gastrulation that integrates spatial and developmental patterning information. We show that MRCK-1 is required for activation of contractile actomyosin dynamics and elevated cortical tension in the apical cell cortex of endodermal precursor cells. MRCK-1 is apically localized by active Cdc42 at the external, cell-cell contact-free surfaces of apically constricting cells, downstream of cell fate determination mechanisms. We establish that the junctional components α-catenin, β-catenin, and cadherin become highly enriched at the apical junctions of apically-constricting cells, and that MRCK-1 and myosin activity are required in vivo for this enrichment. Taken together, our results define mechanisms that position a myosin activator to a specific cell surface where it both locally increases cortical tension and locally enriches junctional components to facilitate apical constriction. These results reveal crucial links that can tie spatial information to local force generation to drive morphogenesis. PMID:27451898

Constriction model of actomyosin ring for cytokinesis by fission yeast using a two-state sliding filament mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Yong-Woon; Mascagni, Michael, E-mail: Mascagni@fsu.edu

2014-09-28

We developed a model describing the structure and contractile mechanism of the actomyosin ring in fission yeast, Schizosaccharomyces pombe. The proposed ring includes actin, myosin, and α-actinin, and is organized into a structure similar to that of muscle sarcomeres. This structure justifies the use of the sliding-filament mechanism developed by Huxley and Hill, but it is probably less organized relative to that of muscle sarcomeres. Ring contraction tension was generated via the same fundamental mechanism used to generate muscle tension, but some physicochemical parameters were adjusted to be consistent with the proposed ring structure. Simulations allowed an estimate of ringmore » constriction tension that reproduced the observed ring constriction velocity using a physiologically possible, self-consistent set of parameters. Proposed molecular-level properties responsible for the thousand-fold slower constriction velocity of the ring relative to that of muscle sarcomeres include fewer myosin molecules involved, a less organized contractile configuration, a low α-actinin concentration, and a high resistance membrane tension. Ring constriction velocity is demonstrated as an exponential function of time despite a near linear appearance. We proposed a hypothesis to explain why excess myosin heads inhibit constriction velocity rather than enhance it. The model revealed how myosin concentration and elastic resistance tension are balanced during cytokinesis in S. pombe.« less

Abdominal rigidity

MedlinePlus

... other symptoms do you have at the same time? For example, do you have abdominal pain ? You may have the following tests: Barium studies of the stomach and intestines (such as an upper GI series ) Blood tests Colonoscopy Gastroscopy Peritoneal lavage Stool studies ...

Abdominal Twin Pressure Sensors for the assessment of abdominal injuries in Q dummies: in-dummy evaluation and performance in accident reconstructions.

PubMed

Beillas, Philippe; Alonzo, François; Chevalier, Marie-Christine; Lesire, Philippe; Leopold, Franck; Trosseille, Xavier; Johannsen, Heiko

2012-10-01

The Abdominal Pressure Twin Sensors (APTS) for Q3 and Q6 dummies are composed of soft polyurethane bladders filled with fluid and equipped with pressure sensors. Implanted within the abdominal insert of child dummies, they can be used to detect abdominal loading due to the belt during frontal collisions. In the present study - which is part of the EC funded CASPER project - two versions of APTS (V1 and V2) were evaluated in abdominal belt compression tests, torso flexion test (V1 only) and two series of sled tests with degraded restraint conditions. The results suggest that the two versions have similar responses, and that the pressure sensitivity to torso flexion is limited. The APTS ability to detect abdominal loading in sled tests was also confirmed, with peak pressures typically below 1 bar when the belt loaded only the pelvis and the thorax (appropriate restraint) and values above that level when the abdomen was loaded directly (inappropriate restraint). Then, accident reconstructions performed as part of CASPER and previous EC funded projects were reanalyzed. Selected data from 19 dummies (12 Q6 and 7 Q3) were used to plot injury risk curves. Maximum pressure, maximum pressure rate and their product were all found to be injury predictors. Maximum pressure levels for a 50% risk of AIS3+ were consistent with the levels separating appropriate and inappropriate restraint in the sled tests (e.g. 50% risk of AIS3+ at 1.09 bar for pressure filtered CFC180). Further work is needed to refine the scaling techniques between ages and confirm the risk curves.

Orchiopexy for intra-abdominal testes: factors predicting success.

PubMed

Stec, Andrew A; Tanaka, Stacy T; Adams, Mark C; Pope, John C; Thomas, John C; Brock, John W

2009-10-01

Intra-abdominal testes can be treated with several surgical procedures. We evaluated factors influencing the outcome of orchiopexy for intra-abdominal testis. We retrospectively reviewed 156 consecutive orchiopexies performed for intra-abdominal testis, defined as a nonpalpable testis on examination and located in the abdomen at surgery. All surgical approaches were included in the study. Primary outcome was the overall success rate and secondary outcomes were success based on surgical approach, age and a patent processus vaginalis. Success was considered a testis with normal texture and size compared to the contralateral testis at followup. Multivariate analysis was performed to determine factors predictive of success. The overall success rate of all orchiopexies was 79.5%. Median patient age at orchiopexy was 12 months and mean followup was 16 months. Of the patients 117 had a patent processus vaginalis at surgery. One-stage abdominal orchiopexy was performed in 92 testes with 89.1% success. Of these cases 32 were performed laparoscopically with 96.9% success. One-stage Fowler-Stephens orchiopexy was performed in 27 testes and 2-stage Fowler-Stephens orchiopexy was performed in 37 with success in 63.0% and 67.6%, respectively. Multivariate analysis revealed that 1-stage orchiopexy without vessel division had more successful outcomes than 1 and 2-stage Fowler-Stephens orchiopexy (OR 0.24, p = 0.007 and 0.29, p = 0.19, respectively). Neither age at surgery nor an open internal ring was significant (p = 0.49 and 0.12, respectively). The overall success of orchiopexy for intra-abdominal testis is 79.5%. While patient selection remains a critical factor, 1-stage orchiopexy without vessel division was significantly more successful and a laparoscopic approach was associated with the fewest failures for intra-abdominal testes.

Assessment of abdominal muscle function using the Biodex System-4. Validity and reliability in healthy volunteers and patients with giant ventral hernia.

PubMed

Gunnarsson, U; Johansson, M; Strigård, K

2011-08-01

The decrease in recurrence rates in ventral hernia surgery have led to a redirection of focus towards other important patient-related endpoints. One such endpoint is abdominal wall function. The aim of the present study was to evaluate the reliability and external validity of abdominal wall strength measurement using the Biodex System-4 with a back abdomen unit. Ten healthy volunteers and ten patients with ventral hernias exceeding 10 cm were recruited. Test-retest reliability, both with and without girdle, was evaluated by comparison of measurements at two test occasions 1 week apart. Reliability was calculated by the interclass correlation coefficients (ICC) method. Validity was evaluated by correlation with the well-established International Physical Activity Questionnaire (IPAQ) and a self-assessment of abdominal wall strength. One person in the healthy group was excluded after the first test due to neck problems following minor trauma. The reliability was excellent (>0.75), with ICC values between 0.92 and 0.97 for the different modalities tested. No differences were seen between testing with and without a girdle. Validity was also excellent both when calculated as correlation to self-assessment of abdominal wall strength, and to IPAQ, giving Kendall tau values of 0.51 and 0.47, respectively, and corresponding P values of 0.002 and 0.004. Measurement of abdominal muscle function using the Biodex System-4 is a reliable and valid method to assess this important patient-related endpoint. Further investigations will be made to explore the potential of this technique in the evaluation of the results of ventral hernia surgery, and to compare muscle function after different abdominal wall reconstruction techniques.

Distinct constrictive processes, separated in time and space, divide caulobacter inner and outer membranes.

PubMed

Judd, Ellen M; Comolli, Luis R; Chen, Joseph C; Downing, Kenneth H; Moerner, W E; McAdams, Harley H

2005-10-01

Cryoelectron microscope tomography (cryoEM) and a fluorescence loss in photobleaching (FLIP) assay were used to characterize progression of the terminal stages of Caulobacter crescentus cell division. Tomographic cryoEM images of the cell division site show separate constrictive processes closing first the inner membrane (IM) and then the outer membrane (OM) in a manner distinctly different from that of septum-forming bacteria. FLIP experiments had previously shown cytoplasmic compartmentalization (when cytoplasmic proteins can no longer diffuse between the two nascent progeny cell compartments) occurring 18 min before daughter cell separation in a 135-min cell cycle so the two constrictive processes are separated in both time and space. In the very latest stages of both IM and OM constriction, short membrane tether structures are observed. The smallest observed pre-fission tethers were 60 nm in diameter for both the inner and outer membranes. Here, we also used FLIP experiments to show that both membrane-bound and periplasmic fluorescent proteins diffuse freely through the FtsZ ring during most of the constriction procession.

Architecture of the ring formed by the tubulin homologue FtsZ in bacterial cell division

PubMed Central

Szwedziak, Piotr; Wang, Qing; Bharat, Tanmay A M; Tsim, Matthew; Löwe, Jan

2014-01-01

Membrane constriction is a prerequisite for cell division. The most common membrane constriction system in prokaryotes is based on the tubulin homologue FtsZ, whose filaments in E. coli are anchored to the membrane by FtsA and enable the formation of the Z-ring and divisome. The precise architecture of the FtsZ ring has remained enigmatic. In this study, we report three-dimensional arrangements of FtsZ and FtsA filaments in C. crescentus and E. coli cells and inside constricting liposomes by means of electron cryomicroscopy and cryotomography. In vivo and in vitro, the Z-ring is composed of a small, single-layered band of filaments parallel to the membrane, creating a continuous ring through lateral filament contacts. Visualisation of the in vitro reconstituted constrictions as well as a complete tracing of the helical paths of the filaments with a molecular model favour a mechanism of FtsZ-based membrane constriction that is likely to be accompanied by filament sliding. DOI: http://dx.doi.org/10.7554/eLife.04601.001 PMID:25490152

Theoretical study on the constricted flow phenomena in arteries

NASA Astrophysics Data System (ADS)

Sen, S.; Chakravarty, S.

2012-12-01

The present study is dealt with the constricted flow characteristics of blood in arteries by making use of an appropriate mathematical model. The constricted artery experiences the generated wall shear stress due to flow disturbances in the presence of constriction. The disturbed flow in the stenosed arterial segment causes malfunction of the cardiovascular system leading to serious health problems in the form of heart attack and stroke. The flowing blood contained in the stenosed artery is considered to be non-Newtonian while the flow is treated to be two-dimensional. The present pursuit also accounts for the motion of the arterial wall and its effect on local fluid mechanics. The flow analysis applies the time-dependent, two-dimensional incompressible nonlinear Navier-Stokes equations for non-Newtonian fluid representing blood. An extensive quantitative analysis presented at the end of the paper based on large scale numerical computations of the quantities of major physiological significance enables one to estimate the constricted flow characteristics in the arterial system under consideration which deviates significantly from that of normal physiological flow conditions.

Pharmacological constriction of the lower oesophageal sphincter: a simple method of arresting variceal haemorrhage.

PubMed Central

Hosking, S W; Doss, W; el-Zeiny, H; Robinson, P; Barsoum, M S; Johnson, A G

1988-01-01

The effect of pharmacological constriction of the lower oesophageal sphincter (LOS) on oesophageal varices was investigated in an experimental study followed by a controlled clinical trial. In the experimental study intravariceal pressure was measured just above the LOS in 11 patients before and after constricting the LOS by intravenous pentagastrin. Intravariceal pressure fell from a mean of 23 (range 12-36) mmHg to 4 (range 0-7) mmHg (p less than 0.001). This marked pressure drop indicated the considerable compression of varices that occurred within the LOS. A prospective controlled clinical trial examined whether LOS constriction (effected by the longer acting metoclopramide) would compress varices sufficiently to arrest active variceal bleeding originating from the lowest 2 cm oesophagus--the area encircled by the LOS. Of 11 patients who received metoclopramide, 10 stopped bleeding compared with four of the 11 who received placebo (p less than 0.01). Pharmacological constriction of the LOS appears to offer a new and effective approach for arresting active bleeding from oesophageal varices. PMID:3044932

[Measurement of cognitive constriction in suicide notes].

PubMed

Heinrich, Monika; Berzlanovich, Andrea; Willinger, Ulrike; Eisenwort, Brigitte

2008-01-01

The target of this paper was to quantify the amount of cognitive constriction in German-language suicide notes by studying quantitative psycholinguistic parameters of texts. This should give a better understanding of presuicidal events and encourage improvement in the field of suicide prevention and crisis intervention. The study is based on letters of the "Vienna Corpus of Suicide Notes". To prove various hypotheses a factor analysis, a number of regression analyses, and the General Linear Model were applied, apart from descriptive methods. The 16 parameters could be reduced to five factors of cognitive constriction, such as the writing style, the usage of words, the dichotomy, the length and the grammatical correctness of the suicide notes. Regarding the writing style the highest values of cognitive constriction were found among women (p=0.005), young persons (p< or =0.000), in short letters (p=0.027) and if psychological problems were the motive for suicide (p=0.020). The discovery site of the letters (p=0.002) was important as well. The construct of cognitive constriction is a multidimensional and complex phenomenon. Therefore the quantification must contain variables of the persons and the texts.

Coordination of peptidoglycan synthesis and outer membrane constriction during Escherichia coli cell division

PubMed Central

Gray, Andrew N; Egan, Alexander JF; van't Veer, Inge L; Verheul, Jolanda; Colavin, Alexandre; Koumoutsi, Alexandra; Biboy, Jacob; Altelaar, A F Maarten; Damen, Mirjam J; Huang, Kerwyn Casey; Simorre, Jean-Pierre; Breukink, Eefjan; den Blaauwen, Tanneke; Typas, Athanasios; Gross, Carol A; Vollmer, Waldemar

2015-01-01

To maintain cellular structure and integrity during division, Gram-negative bacteria must carefully coordinate constriction of a tripartite cell envelope of inner membrane, peptidoglycan (PG), and outer membrane (OM). It has remained enigmatic how this is accomplished. Here, we show that envelope machines facilitating septal PG synthesis (PBP1B-LpoB complex) and OM constriction (Tol system) are physically and functionally coordinated via YbgF, renamed CpoB (Coordinator of PG synthesis and OM constriction, associated with PBP1B). CpoB localizes to the septum concurrent with PBP1B-LpoB and Tol at the onset of constriction, interacts with both complexes, and regulates PBP1B activity in response to Tol energy state. This coordination links PG synthesis with OM invagination and imparts a unique mode of bifunctional PG synthase regulation by selectively modulating PBP1B cross-linking activity. Coordination of the PBP1B and Tol machines by CpoB contributes to effective PBP1B function in vivo and maintenance of cell envelope integrity during division. DOI: http://dx.doi.org/10.7554/eLife.07118.001 PMID:25951518

Constriction band syndrome occurring in the setting of in vitro fertilization and advanced maternal age

PubMed Central

Rinker, Brian; Vasconez, Henry C

2006-01-01

The debate as to the pathogenesis of constriction band syndrome began with Hippocrates and continues today. The exogenous theory attributes the condition to entanglement of the fetus in the amniotic remnants following premature rupture of the amnion, which is in contrast to the endogenous, or genetic, mechanism. A case of constriction band syndrome in the setting of in vitro fertilization, where the child was genetically unrelated to the birth mother, is presented. Constriction band syndrome has been reported following amniocentesis and chorionic villus sampling, but it has not heretofore been presented in the setting of in vitro fertilization. In addition, the present case presents an opportunity to separate maternal from genetic factors and, possibly, shed some light on the etiology of the condition. PMID:19554231

Unconventional transport in ultraclean graphene constriction devices

NASA Astrophysics Data System (ADS)

Pita Vidal, Marta; Ma, Qiong; Watanabe, Kenji; Taniguchi, Takashi; Jarillo-Herrero, Pablo

Under mesoscopic conditions, strong electron-electron interactions and weak electron-phonon coupling in graphene lead to hydrodynamic behavior of electrons, resulting in unusual and unexpected transport phenomena. Specifically, this hydrodynamical collective cooperation of electrons is predicted to enhance the flow of electrical current, leading to a striking higher-than-ballistic conductance through a narrow geometrical constriction. To access the hydrodynamic regime, we fabricated high-quality, low-disorder graphene nano-constriction devices encapsulated by hexagonal boron nitride, where electron-electron scattering dominates impurity scattering. We will report on our systematic four-probe conductance measurements on devices with different constriction widths as a function of number density and temperature. The observation of quantum transport phenomena that are inconsistent with the non-interacting ballistic free-fermion model would suggest a macroscopic transport signature of electron viscosity.

Lactose and Fructose Intolerance in Turkish Children with Chronic Abdominal Pain.

PubMed

Yuce, Ozlem; Kalayci, Ayhan Gazi; Comba, Atakan; Eren, Esra; Caltepe, Gonul

2016-05-08

To investigate the prevalence of lactose and fructose intolerance in children with chronic abdominal pain. Hydrogen breath tests were done to detect lactose and fructose malabsorption in 86 children with chronic abdominal pain (44 irritable bowel syndrome, 24 functional abdominal pain and 17 functional abdominal pain syndrome as per Rome III criteria) presenting to a Pediatric Gastroentreology department. 14 (16.3%) of patients were diagnosed with lactose intolerance and 11 (12.8%) with fructose intolerance. Lactose and fructose intolerance in children can lead to chronic abdominal pain and symptoms improve with dietary modifications.

LabLessons: Effects of Electronic Prelabs on Student Engagement and Performance

ERIC Educational Resources Information Center

Gryczka, Patrick; Klementowicz, Edward; Sharrock, Chappel; Maxfield, MacRae; Montclare, Jin Kim

2016-01-01

Lab instructors, for both high school and undergraduate college level courses, face issues of constricted time within the lab period and limited student engagement with prelab materials. To address these issues, an online prelab delivery system named LabLessons is developed and tested out in a high school chemistry classroom. The system…

The Development of Peripheral Vision in Infants.

ERIC Educational Resources Information Center

Guez, Jean R.

This study investigated the extent of infant peripheral vision, specifically the extent of infants' constricted field, or tunnel vision. Thirteen infants, 2 to 5 months old, were tested using a psychophysical procedure to obtain contrast sensitivity thresholds at four retinal loci (-40, -15, +15, +40 deg.). Infants were placed in an infant bed in…

Constriction of bovine vasculature by endophyte-infected tall fescue seed extract is similar to pure ergovaline

USDA-ARS?s Scientific Manuscript database

Ergovaline has been extensively used to study vasoactive effects of endophyte- (Neotyphodium coenophialum) infected tall fescue (Lolium arundinaceum). However, preliminary in vitro tests indicated that an extract of toxic tall fescue seed (E+EXT) is more potent than ergovaline alone in a right rumin...

Antinociceptive and anti-inflammatory effects of the methanolic stem bark extract of Antrocaryon klaineanum Pierre (Anacardiaceae) in mice and rat.

PubMed

Fongang, Annie Laure Magne; Laure Nguemfo, Edwige; Djouatsa Nangue, Yolande; Bogning Zangueu, Calvin; Fouokeng, Yannick; Azebaze, Anatole Guy Blaise; José Llorent-Martínez, Eulogio; Córdova, Maria Luisa Fernández-de; Bertrand Dongmo, Alain; Vierling, Wolfgang

2017-05-05

Antrocaryon klaineanum is used by traditional healers to treat many disorders including pain and inflammatory diseases. This study aimed to evaluate the analgesic and antiinflammatory activities of methanol extract of A. klaineanum in mice and rats. Reverse phase high-performance liquid chromatography (RP-HPLC) was performed to establish the chromatographic fingerprint and to identify various chemical components of the plant extract. The anti-nociceptive activity of methanol extract of A. klaineanum was assessed using the acetic acid-induced abdominal constriction model, formalin test, capsaicin and cinnamaldehyde induced-neurogenic pain and hot plate test. Anti-inflammatory activity was assessed on carrageenan-induced inflammation. Extract was administrated orally at 200, 400 and 600mg/kg. Phytochemical analysis indicated the presence of proanthocyanidins, phenolic acids and flavonoids. The results of anti-nociceptive and anti-inflammatory activities showed that methanol extract significantly (p<0.01) reduced the pain induced by acetic acid with an inhibition percentage of 45.49% (600mg/kg). In the formalin test, the extract also significantly (p<0.01) reduced linking time in both phase (neurogenic and inflammatory) of the test with inhibition percentage of 56.28% and 60.73% respectively at the dose of 600mg/kg. The methanol extract of A. klaineanum significantly (P<0.001) reduced neurogenic pain linking time induced by capsaicin and cinnamaldehyde by 82.54% and 75.94% at the highest dose (600mg/kg) respectively. More over the extract significantly increase the reaction time in hot plate test. In the inflammatory test, the plant extract significantly reduced the carrageen induced rat paw oedema from 30min to 6h with a maximum percentage inhibition of 89.88% (6h) at the dose of 600mg/kg. These results demonstrate that the methanol extract of A. klaineanum may possess analgesic and anti-inflammatory effects and provide support of the traditional use of this plant in the treatment of different pain and inflammatory conditions. Further investigation could reveal metabolites of the extract responsible for the observed effects. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Effects of Voluntary Locomotion and Calcitonin Gene-Related Peptide on the Dynamics of Single Dural Vessels in Awake Mice

PubMed Central

Gao, Yu-Rong

2016-01-01

The dura mater is a vascularized membrane surrounding the brain and is heavily innervated by sensory nerves. Our knowledge of the dural vasculature has been limited to pathological conditions, such as headaches, but little is known about the dural blood flow regulation during behavior. To better understand the dynamics of dural vessels during behavior, we used two-photon laser scanning microscopy (2PLSM) to measure the diameter changes of single dural and pial vessels in the awake mouse during voluntary locomotion. Surprisingly, we found that voluntary locomotion drove the constriction of dural vessels, and the dynamics of these constrictions could be captured with a linear convolution model. Dural vessel constrictions did not mirror the large increases in intracranial pressure (ICP) during locomotion, indicating that dural vessel constriction was not caused passively by compression. To study how behaviorally driven dynamics of dural vessels might be altered in pathological states, we injected the vasodilator calcitonin gene-related peptide (CGRP), which induces headache in humans. CGRP dilated dural, but not pial, vessels and significantly reduced spontaneous locomotion but did not block locomotion-induced constrictions in dural vessels. Sumatriptan, a drug commonly used to treat headaches, blocked the vascular and behavioral the effects of CGRP. These findings suggest that, in the awake animal, the diameters of dural vessels are regulated dynamically during behavior and during drug-induced pathological states. SIGNIFICANT STATEMENT The vasculature of the dura has been implicated in the pathophysiology of headaches, but how individual dural vessels respond during behavior, both under normal conditions and after treatment with the headache-inducing peptide calcitonin gene-related peptide (CGRP), is poorly understood. To address these issues, we imaged individual dural vessels in awake mice and found that dural vessels constricted during voluntary locomotion, and this constriction did not follow locomotion-induced intracranial pressure increases. CGRP injection caused baseline dural vessel dilation and reduced locomotion but did not block locomotion-induced constrictions of dural vessels or affect pial vessels. These novel findings reveal dynamic regulation of dural vessels that are distinct from those in cerebral blood vessels during both normal behavior and after dilation by CGRP. PMID:26911696

Lead toxicity as an etiology for abdominal pain in the emergency department.

PubMed

Moriarity, Risa S; Harris, James T; Cox, Robert D

2014-02-01

Abdominal pain is an uncommon presentation of lead toxicity in the emergency department (ED). However, making the diagnosis is important in avoiding unnecessary testing and the long-term sequelae of lead toxicity. To illustrate possible presentations of abdominal pain secondary to lead toxicity and highlight the importance of taking a thorough patient history. We report 2 patients who presented to the ED with abdominal pain and underwent extensive evaluations that did not reveal an etiology. At follow-up visits, their occupational histories revealed possible lead exposures from working for a bullet-recycling company. Tests revealed that each patient had extremely high lead levels and they were both treated for lead toxicity. Their abdominal pain resolved as their lead levels decreased. These cases demonstrate a rare but significant cause of abdominal pain in the ED. Although history-taking in the ED is necessarily brief, these cases underscore the importance of obtaining an occupational history. Copyright © 2014 Elsevier Inc. All rights reserved.

Abdominal Pain-Predominant Functional Gastrointestinal Disorders in Jordanian School Children.

PubMed

Altamimi, Eyad M; Al-Safadi, Mohammad H

2014-12-01

Recurrent abdominal pain (RAP) is a common complaint in children. Significant portion of them are of functional origin. This study aimed to assess the prevalence of abdominal pain-predominant functional gastrointestinal disorder (FGID) and its types in Jordanian school children. This is a school-based survey at south Jordan. Information using the self-reporting form of the Questionnaire on Pediatric Gastrointestinal Symptoms-Rome III Version (QPGS-RIII) - the official Arabic translation - was collected. Classes from academic years (grades) 6 - 8 were selected. SPSS Statistical Package Version 17 (IBM, Armonk, NY, USA) was used. Categorical data were analyzed using Fisher's exact test, and continuous data were analyzed using t -test. P < 0.05 was considered significant. Five hundred questionnaires were distributed, and 454 returned answered (91%). Two hundred twenty-nine (50.8%) were males. The average age of participants was 12.7 years (11 - 15 years). One hundred sixteen (25.7%) had abdominal pain-predominant FGID. Seventy-nine (68%) of them were females. Forty-seven (10.6%) had irritable bowel syndrome (IBS). Thirty-six (8%), 17 (3.8%), 11 (2.4%) and five (1.1%) had abdominal migraine, functional abdominal pain, functional abdominal pain syndrome and functional dyspepsia, respectively. Abdominal pain-predominant FGID has become a major health issue in Jordanian children. One of four children between the ages of 11 and 15 years exhibits at least one abdominal pain-predominant FGID. The most common form of abdominal pain-predominant FGID in our children was IBS. Females are affected more often than males. Intestinal and extra-intestinal symptoms are seen regularly with abdominal pain-predominant FGIDs.

Navigating recurrent abdominal pain through clinical clues, red flags, and initial testing.

PubMed

Noe, Joshua D; Li, B U K

2009-05-01

Recurrent abdominal pain is a common chronic complaint that presents to your office. The constant challenge is one of detecting those with organic disease from the majority who have a functional pain disorder including functional dyspepsia, irritable bowel syndrome, functional abdominal pain, and abdominal migraine. Beginning with a detailed history and physical exam, you can: 1) apply the symptom-based Rome III criteria to positively identify a functional disorder, and 2) filter these findings through the diagnostic clues and red flags that point toward specific organic disease and/or further testing. Once a functional diagnosis has been made or an organic disease is suspected, you can initiate a self-limited empiric therapeutic trial. With this diagnostic approach, you should feel confident navigating through the initial evaluation, management, and consultation referral for a child or adolescent with recurrent abdominal pain.

Pressure overload stimulated cardiac hypertrophy leads to a rapid decrease in the mRNA for creatine kinase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boheler, K.; Popovich, B.; Dillmann, W.H.

1987-05-01

Cardiac hypertrophy (CH) leads to a decrease in creatine kinase (CK) enzymatic activity. To determine if the mRNA for CK also decreases with CH, they performed the following studies. Cardiac RNA was isolated from rats subjected to either abdominal aortic stenosis (AS) or sham surgery. Through Northern blot analysis, total cardiac RNA was quantitated with a CK specific /sup 32/P-labelled cDNA clone. At 3 and 8 days post-constriction, the mRNA for CK decreases by 54.6 +/- 7% and 65.3 +/- 18% respectively, whereas the heart weight increases by 19% and 37% relative to controls. Further studies indicate that CK mRNAmore » also decreases by 41.8% in hypothyroid rats (Tx) but decreases by a total of 68.1% in Tx rats subjected to 8 days of AS. Pressure overload stimulated CH leads to a rapid decrease in CK mRNA in normal and Tx rats. This CK mRNA decrease may account for the decreased efficiency of contraction seen in CH.« less

Discovery of phenylsulfonylfuroxan derivatives as gamma globin inducers by histone acetylation.

PubMed

Melo, Thais Regina Ferreira de; Kumkhaek, Chutima; Fernandes, Guilherme Felipe Dos Santos; Lopes Pires, Maria Elisa; Chelucci, Rafael Consolin; Barbieri, Karina Pereira; Coelho, Fernanda; Capote, Ticiana Sidorenko de Oliveira; Lanaro, Carolina; Carlos, Iracilda Zeppone; Marcondes, Sisi; Chegaev, Konstantin; Guglielmo, Stefano; Fruttero, Roberta; Chung, Man Chin; Costa, Fernando Ferreira; Rodgers, Griffin P; Dos Santos, Jean Leandro

2018-05-28

N-oxide derivatives 5(a-b), 8(a-b), and 11(a-c) were designed, synthesized and evaluated in vitro and in vivo as potential drugs that are able to ameliorate sickle cell disease (SCD) symptoms. All of the compounds demonstrated the capacity to releasing nitric oxide at different levels ranging from 0.8 to 30.1%, in vivo analgesic activity and ability to reduce TNF-α levels in the supernatants of monocyte cultures. The most active compound (8b) protected 50.1% against acetic acid-induced abdominal constrictions, while dipyrone, which was used as a control only protected 35%. Compounds 8a and 8b inhibited ADP-induced platelet aggregation by 84% and 76.1%, respectively. Both compounds increased γ-globin in K562 cells at 100 μM. The mechanisms involved in the γ-globin increase are related to the acetylation of histones H3 and H4 that is induced by these compounds. In vitro, the most promising compound (8b) was not cytotoxic, mutagenic and genotoxic. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Macrophage Migration Inhibitory Factor Deletion Exacerbates Pressure Overload-Induced Cardiac Hypertrophy through Mitigating Autophagy

PubMed Central

Xu, Xihui; Hua, Yinan; Nair, Sreejayan; Bucala, Richard; Ren, Jun

2014-01-01

The proinflammatory cytokine macrophage migration inhibitory factor (MIF) has been shown to be cardioprotective in various pathological conditions. However, the underlying mechanisms still remain elusive. In this study, we revealed that MIF deficiency overtly exacerbated abdominal aorta constriction (AAC)-induced cardiac hypertrophy and contractile anomalies. MIF deficiency interrupted myocardial autophagy in hypertrophied hearts. Rapamycin administration mitigated the exacerbated hypertrophic responses in MIF−/− mice. Using the phenylephrine-induced hypertrophy in vitro model in H9C2 myoblasts, we confirmed that MIF governed activation of AMPK-mTOR-autophagy cascade. Confocal microscopic examination demonstrated that MIF depletion prevented phenylephrine-induced mitophagy in H9C2 myoblasts. Myocardial Parkin, an E3 ubiquitin ligase and a marker for mitophagy, was significantly upregulated following sustained pressure overload, the effect of which was prevented by MIF knockout. Moreover, our data exhibited that levels of MIF, AMPK activation and autophagy were elevated concurrently in human failing hearts. These data indicate that endogenous MIF regulates the mTOR signaling to activate autophagy to preserve cardiac geometry and protect against hypertrophic responses. PMID:24366076

Antinociceptive and Anti-Inflammatory Effects of Octacosanol from the Leaves of Sabicea grisea var. grisea in Mice

PubMed Central

de Oliveira, Anderson Marques; Conserva, Lucia M.; de Souza Ferro, Jamylle N.; de Almeida Brito, Fabíola; Lyra Lemos, Rosângela P.; Barreto, Emiliano

2012-01-01

Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. grisea Cham. & Schltdl (Rubiaceae), an endemic plant in Brazil, resulted in the isolation of octacosanol. This study investigated the antinociceptive and anti-inflammatory effects of the octacosanol in different experimental models. The crude ethanolic extract and hexane fraction obtained from the leaves of S. grisea produced an inhibition of acetic acid-induced pain. Moreover, octacosanol isolated from the hexane fraction produced a significant inhibition of pain response elicited by acetic acid. Pre-treatment with yohimbine, an alpha 2-adrenergic receptor antagonist, notably reversed the antinociceptive activity induced by octacosanol in the abdominal constriction test. Furthermore, mice treated with octacosanol did not exhibit any behavioral alteration during the hot plate and rota-rod tests, indicating non-participation of the supraspinal components in the modulation of pain by octacosanol with no motor abnormality. In the formalin test, octacosanol did not inhibit the licking time in first phase (neurogenic pain), but significantly inhibited the licking time in second phase (inflammatory pain) of mice. The anti-inflammatory effect of octacosanol was evaluated using carrageenan-induced pleurisy. The octacosanol significantly reduced the total leukocyte count and neutrophils influx, as well as TNF-α levels in the carrageenan-induced pleurisy. This study revealed that the mechanism responsible for the antinociceptive and anti-inflammatory effects of the octacosanol appears to be partly associated with an inhibition of alpha 2-adrenergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, these results demonstrated that the octacosanol from the leaves of S. grisea possesses antinociceptive and anti-inflammatory activities, which could be of relevance for the pharmacological control of pain and inflammatory processes. PMID:22408410

Experimental evaluation of anti-inflammatory, antinociceptive and antipyretic activities of clove oil in mice

PubMed Central

Taher, Yousef A.; Samud, Awatef M.; El-Taher, Fathy E.; ben-Hussin, Ghazala; Elmezogi, Jamal S.; Al-Mehdawi, Badryia F.; Salem, Hanan A.

2015-01-01

Background Clove oil of Eugenia caryophyllata (Myrtaceae) is a light yellowish fluid obtained from dried flower buds. Clove oil is used traditionally to relieve toothache. Aim The aim of the present work was to study the anti-inflammatory, antinociceptive and antipyretic potential of clove oil in mice. Methods Analgesic activity was examined using acetic-acid-induced abdominal constrictions and the hot plate test. Carrageenan-induced paw edema and brewer's-yeast-induced pyrexia were used to investigate the anti-inflammatory activity and the antipyretic effects, respectively. The oil was administered intraperitoneally (i.p.) at a dose of 33 mg/kg body weight and the effects were compared with reference drugs. Results In the antinociceptive test, mice treated with clove oil exhibited significantly decreased acetic-acid-induced writhing movements by a maximum of 87.7% (p<0.01) compared with a decrease of 77.7% (p<0.01) in response to aspirin injection (100 mg/kg, intraperitoneal, i.p.). Similarly, in the hot plate test, clove oil significantly increased the reaction latency to pain after 60 min by 82.3% (p<0.05) compared with morphine value of 91.7% (p<0.01). In addition, clove oil and indomethacin produced anti-inflammatory effects, as demonstrated by respectively 50.6% (p<0.05) and 70.4% (p<0.01) inhibition of mouse paw edema induced by carrageenan. Furthermore, clove oil significantly attenuated the hyperthermia induced by yeast at ΔT-max by 2.7°C (p<0.001), and time of peak effects was 30–180 min compared with a paracetamol value ΔT-max of 3.2°C (p<0.001). The estimated i.p. LD50 of clove oil was 161.9 mg/kg. Phytochemical screening of the oil showed the presence of eugenol. Conclusion The present findings demonstrate the potential pharmacological properties of clove oil and provide further a support for its reported use in folk medicine. PMID:26333873

Comparison of adenosine, isoflurane, and desflurane on myocardial tissue oxygen pressure during coronary artery constriction in dogs.

PubMed

Hoffman, William E; Albrecht, Ronald F; Jonjev, Zivojin S

2003-08-01

To compare adenosine-, isoflurane-, or desflurane-induced hypotension with and without left anterior descending (LAD) coronary artery constriction for the effects on myocardial tissue oxygen pressure (PmO(2)) in dogs. Prospective, randomized, nonblinded. University teaching hospital. Male nonpurpose-bred dogs (n = 18). Dogs were anesthetized with 1.5% isoflurane (n = 12) or 8% desflurane (n = 6). A flow probe and balloon occluder were placed on the LAD artery. A probe that measured myocardial oxygen pressure was inserted into the middle myocardium in the LAD region. Myocardial oxygen consumption (MVO(2)) was calculated as LAD flow x arterial minus coronary sinus oxygen content. Measures were made during hypotension produced by adenosine infusion, 2.8% isoflurane, or 14% desflurane with and without LAD constriction to decrease blood flow 30%. Without LAD artery constriction, adenosine infusion increased LAD flow 90% and MVO(2) 70%, 2.8% isoflurane produced no change in MVO(2), and 14% desflurane decreased MVO(2) 25%, but no treatment changed PmO(2). LAD artery constriction decreased PmO(2) 50% by itself. Adenosine infusion during LAD constriction decreased tissue oxygen pressure an additional 60%, 2.8% isoflurane produced no change, and 14% desflurane increased PmO(2) 100%. There was an inverse relationship between the effect of adenosine, 2.8% isoflurane, and 14% desflurane on MVO(2) and PmO(2) during ischemia. This is consistent with reports that increasing oxygen demand worsens myocardial ischemia.

Airway disease: anatomopathologic patterns and functional correlations.

PubMed

Mormile, F; Ciappi, G

1997-01-01

Airways represent a serial and parallel branched system, through which the alveoli are connected with the external air. They participate in the mechanical and immune defense against noxious agents, regional flow regulation to optimize the perfusion/ventilation ratio and provide lung mechanical support. Functional exploration of central airways is based on resistance measurement, flow-volume curve or spirometry, while peripheral airways influence parameters as the upstream resistance, the slope of phase III nitrogen washout and the residual volume. Bronchodynamic tests supply important information on airway reversibility and nonspecific reactivity. Anatomopathologic alterations of obstructive chronic bronchitis, pulmonary emphysema and bronchial asthma account for their specific functional and bronchodynamic alterations. There is a growing interest for bronchiolitis in the clinical, radiologic and functional field. This type of lesion, always present in COPD, asthma and interstitial disease, becomes relevant when isolated or predominant. The most useful anatomofunctional classification separates the "constrictive" forms, the cause of obstruction and hyperinflation, from "proliferative" forms where an intraluminal proliferation more or less extended to alveolar air spaces as in BOOP (bronchiolitis obliterans organizing pneumonia) results in restrictive dysfunction. Constrictive bronchiolitis obliterans represents a severe and frequent complication of lung and bone marrow transplantation. Idiopathic BOOP may occur with cough or flue-like symptoms. In other cases, constrictive and proliferative forms may have a toxic (gases or drugs), postinfective or immune etiology (rheumatoid arthritis, LES, etc). Respiratory bronchiolitis or smokers' bronchiolitis, an often asymptomatic lesion, rarely associated to an interstitial lung disease, should be considered separately. The relationships between respiratory bronchiolitis, COPD and initial centriacinar emphysema is still to be elucidated. The diagnostic combination of the more sensitive functional tests with HRCT will allow a better understanding of the natural history of the various forms of bronchiolitis.

Abdominal epilepsy as an unusual cause of abdominal pain: a case report.

PubMed

Yunus, Yilmaz; Sefer, Ustebay; Dondu, Ulker Ustebay; Ismail, Ozanli; Yusuf, Ehi

2016-09-01

Abdominal pain, in etiology sometimes difficult to be defined, is a frequent complaint in childhood. Abdominal epilepsy is a rare cause of abdominal pain. In this article, we report on 5 year old girl patient with abdominal epilepsy. Some investigations (stool investigation, routine blood tests, ultrasonography (USG), electrocardiogram (ECHO) and electrocardiograpy (ECG), holter for 24hr.) were done to understand the origin of these complaints; but no abnormalities were found. Finally an EEG was done during an episode of abdominal pain and it was shown that there were generalized spikes especially precipitated by hyperventilation. The patient did well on valproic acid therapy and EEG was normal 1 month after beginning of the treatment. The cause of chronic recurrent paroxymal abdominal pain is difficult for the clinicians to diagnose in childhood. A lot of disease may lead to paroxysmal gastrointestinal symptoms like familial mediterranean fever and porfiria. Abdominal epilepsy is one of the rare but easily treatable cause of abdominal pain. In conclusion, abdominal epilepsy should be suspected in children with recurrent abdominal pain.

An experimental abdominal pressure measurement device for child ATDs.

DOT National Transportation Integrated Search

1995-12-01

An experimental device to measure the abdominal pressure in child-size Anthropomorphic Test Dummies (ATDs) during dynamic tests was developed. A description is provided of the two ATDs in which the device was installed, the CRABI six-month-old and th...

Investigation of the immediate pre-operative physical capacity of patients scheduled for elective abdominal surgery using the 6-minute walk test.

PubMed

Soares, S M T P; Jannuzzi, H P C; Kassab, M F O; Nucci, L B; Paschoal, M A

2015-09-01

To evaluate the effects of repetition of the 6-minute walk test in patients scheduled to undergo abdominal surgery within the next 48 hours, and to verify the physical capacity of these subjects before surgery. Cross-sectional study. University teaching hospital. Forty-two patients scheduled for elective abdominal surgery within the next 48 hours. Distance walked in the 6-minute walk test, heart rate, peripheral oxygen saturation, dyspnoea and leg fatigue. Thirty-one patients (74%) were able to walk for a longer distance when the test was repeated. In these subjects, the mean increase in distance walked was 35.4 [standard deviation (SD) 19.9]m. Heart rate, dyspnoea and leg fatigue increased significantly over time on both tests (P<0.05). The mean heart rate at the end of the sixth minute was significantly higher on the second test (P=0.022). Peripheral oxygen saturation remained above 90% in both tests. The furthest distance walked was, on average, 461.3 (SD 89.7)m. This value was significantly lower than that predicted for the sample (P<0.001). Patients scheduled to undergo abdominal surgery were able to walk further when they performed a second 6-minute walk test. Moreover, they showed reduced physical ability before surgery. These findings suggest that repetition of the 6-minute walk test may increase the accuracy of the distance walked, which is useful for studies assessing the physical capacity of patients undergoing abdominal surgery. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

PubMed

ShahAli, Shabnam; Arab, Amir Massoud; Talebian, Saeed; Ebrahimi, Esmaeil; Bahmani, Andia; Karimi, Noureddin; Nabavi, Hoda

2015-07-01

The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP. Copyright © 2014 Elsevier Ltd. All rights reserved.

Experimental and numerical investigation of the sound generation mechanisms of sibilant fricatives using a simplified vocal tract model

NASA Astrophysics Data System (ADS)

Yoshinaga, Tsukasa; Nozaki, Kazunori; Wada, Shigeo

2018-03-01

The sound generation mechanisms of sibilant fricatives were investigated with experimental measurements and large-eddy simulations using a simplified vocal tract model. The vocal tract geometry was simplified to a three-dimensional rectangular channel, and differences in the geometries while pronouncing fricatives /s/ and /∫/ were expressed by shifting the position of the tongue and its constricted flow channel. Experimental results showed that the characteristic peak frequency of the fricatives decreased when the distance between the tongue and teeth increased. Numerical simulations revealed that the jet flow generated from the constriction impinged on the upper teeth wall and caused the main sound source upstream and downstream from the gap between the teeth. While magnitudes of the sound source decreased with increments of the frequency, amplitudes of the pressure downstream from the constriction increased at the peak frequencies of the corresponding tongue position. These results indicate that the sound pressures at the peak frequencies increased by acoustic resonance in the channel downstream from the constriction, and the different frequency characteristics between /s/ and /∫/ were produced by changing the constriction and the acoustic node positions inside the vocal tract.

Frostbite in an adolescent football player: a case report.

PubMed

Rivlin, Michael; King, Marnie; Kruse, Richard; Ilyas, Asif M

2014-01-01

To present the case of vascular compromise of a finger from a confluent circumferential blister due to an inappropriately applied commercial cold pack in a high school athlete and to describe the mechanism of iatrogenic injury, acute surgical management, rehabilitation, and pathophysiology of frostbite and constriction injuries. A 17-year-old male football player presented with a frostbite and constriction injury to the index finger secondary to prolonged use of a cooling pack after a mild traumatic injury to the digit. He developed a prolonged sensory deficit from thermal injury, as well as acute vascular compromise requiring urgent operative intervention. Frostbite and constriction injury to the index finger. Emergency surgical decompression and occupational therapy. Frostbite injuries can occur iatrogenically because of inappropriate use of cooling devices or gel packs. Fingers are commonly injured extremities that are particularly susceptible to frostbite and compression injuries. To our knowledge, no case of vascular compromise from the blister constriction of digits has been reported. Patients and their caregivers must be educated about how to properly use cooling devices. Clinicians need to fully evaluate patients with iatrogenic frostbite injuries, giving particular attention to neurovascular status, and must recognize the need for surgical release of constriction syndrome to prevent substantial morbidity.

Modelling responses of the inert-gas washout and MRI to bronchoconstriction.

PubMed

Foy, Brody H; Kay, David; Bordas, Rafel

2017-01-01

Many lung diseases lead to an increase in ventilation heterogeneity (VH). Two clinical practices for the measurement of patient VH are in vivo imaging, and the inert gas multiple breath washout (MBW). In this study computational modelling was used to compare the responses of MBW indices LCI and s cond and MRI measured global and local ventilation indices, σ r and σ local , to constriction of airways in the conducting zone of the lungs. The simulations show that s cond , LCI and σ r behave quite similarly to each other, all being sensitive to increases in the severity of constriction, while exhibiting little sensitivity to the depth at which constriction occurs. In contrast, the local MRI index σ local shows strong sensitivity to depth of constriction, but lowered sensitivity to constriction severity. We finish with an analysis of the sensitivity of MRI indices to grid sizes, showing that results should be interpreted with reference to the image resolution. Overall we conclude that the application of both local and global VH measures may help to classify different types of bronchoconstriction. Copyright © 2016 Elsevier B.V. All rights reserved.

Active elastohydrodynamics of vesicles in narrow blind constrictions

NASA Astrophysics Data System (ADS)

Fai, T. G.; Kusters, R.; Harting, J.; Rycroft, C. H.; Mahadevan, L.

2017-11-01

Fluid-resistance limited transport of vesicles through narrow constrictions is a recurring theme in many biological and engineering applications. Inspired by the motor-driven movement of soft membrane-bound vesicles into closed neuronal dendritic spines, here we study this problem using a combination of passive three-dimensional simulations and a simplified semianalytical theory for the active transport of vesicles forced through constrictions by molecular motors. We show that the motion of these objects is characterized by two dimensionless quantities related to the geometry and to the strength of forcing relative to the vesicle elasticity. We use numerical simulations to characterize the transit time for a vesicle forced by fluid pressure through a constriction in a channel and find that relative to an open channel, transport into a blind end leads to the formation of a smaller forward-flowing lubrication layer that strongly impedes motion. When the fluid pressure forcing is complemented by forces due to molecular motors that are responsible for vesicle trafficking into dendritic spines, we find that the competition between motor forcing and fluid drag results in multistable dynamics reminiscent of the real system. Our study highlights the role of nonlocal hydrodynamic effects in determining the kinetics of vesicular transport in constricted geometries.

Long-term cardiovascular evaluation of patients with Hodgkin's disease treated by thoracic mantle radiation therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Applefeld, M.M.; Slawson, R.G.; Spicer, K.M.

1982-04-01

The long-term cardiac effects of anterior-weighted thoracic mantle field radiotherapy were assessed in 25 patients treated for Hodgkin's disease. These patients underwent an evaluation that included a careful history and physical examination, ECG, M-mode echocardiogram, exercise ECG-gated radionuclide ventriculography, and cardiac catheterization. In these 25 patients evaluated 37-144 months (median, 96) after completion of thoracic mantle radiotherapy, eight had constrictive pericarditis; eight had occult constrictive pericarditis; three had an abnormal response to fluid challenge; three had suspected or proven occlusive coronary artery disease; and one each had a cardiomyopathy and diminished functional capacity on exercise testing. Only one patient appearsmore » to be normal after evaluation. The clinical spectrum of delayed-appearing radiation-induced cardiac disease in patients treated by anterior-weighted thoracic mantle fields and our suggestions for its treatment are discussed.« less

Chronic calcific constrictive pericarditis complicating Churg-Strauss syndrome: first reported case.

PubMed

Aboukhoudir, Falah; Pansieri, Michel; Rekik, Sofiene

2014-10-01

Churg-Strauss syndrome is a necrotizing systemic vasculitis characterized by extravascular granulomas and eosinophilic infiltrates of small vessels. Although cardiac complications are considered to be relatively common, no case of constrictive calcified pericarditis has ever been previously described in this setting. In this report, we present the case of a 46-year-old man with Churg-Strauss syndrome, in whom we were able to document the development of symptomatic calcific constrictive pericarditis during a 10-year period despite long-term corticosteroid therapy. Georg Thieme Verlag KG Stuttgart · New York.

Etude des sequences de type consonne constrictive plus voyelle en francais, a l'aide de la radiocinematographie et de l'oscillographie (A Study of the Constrictive Consonant Plus Vowel Sequences in French, Using X-Ray Filming and Oscillography). Publication B-148.

ERIC Educational Resources Information Center

Rochette, Claude; Simard, Claude

A study of the phonetic combination of a constrictive consonant (specifically, [f], [v], and [r]) and a vowel in French using x-ray and oscillograph technology focused on the speed and process of articulation between the consonant and the vowel. The study considered aperture size, nasality, labiality, and accent. Articulation of a total of 407…

Glomerular prostaglandins modulate vascular reactivity of the downstream efferent arterioles.

PubMed

Arima, S; Ren, Y; Juncos, L A; Carretero, O A; Ito, S

1994-03-01

The balance of vascular resistance in afferent (Af-) and efferent arterioles (Ef-Arts) is a crucial factor that determines glomerular hemodynamics. We have recently reported that when Ef-Arts were perfused from the distal end of the Af-Art through the glomerulus (orthograde perfusion; OP), both angiotensin II (Ang II) and norepinephrine (NE) induced much weaker constriction than they did when Ef-Arts were perfused from the distal end (retrograde perfusion; RP). This difference was not affected by inhibiting synthesis of nitric oxide. In the present study, we tested the hypothesis that glomerular prostaglandins (PGs) may modulate vascular reactivity of the downstream Ef-Art. In addition, we examined the possible modulatory role of PGs in the Af-Art responses to Ang II or NE. Both Ang II and NE caused dose-dependent constriction of Ef-Arts with either OP or RP; however, the constriction was stronger in RP. At 10(-8) M, Ang II decreased Ef-Art diameter by 35 +/- 3.5% in OP (N = 9) compared to 73 +/- 3.9% in RP (N = 5), while 10(-6) M NE decreased the diameter by 25 +/- 3.6% in OP (N = 9) compared to 62 +/- 7.2% in RP (N = 5). Pretreatment with 5 x 10(-5) M indomethacin (Indo) did not alter basal diameter with either method of perfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Performance based on sEMG activity is related to psychosocial components: differences between back and abdominal endurance tests.

PubMed

Van Damme, Benedicte; Stevens, Veerle; Van Tiggelen, Damien; Perneel, Christiaan; Crombez, Geert; Danneels, Lieven

2014-10-01

The influence of psychosocial components on back and abdominal endurance tests in patients with persistent non-specific low back pain should be investigated to ensure the correct interpretation of these measures. Three-hundred and thirty-two patients (291 men and 41 women) from 19 to 63years performed an abdominal and back muscle endurance test after completing some psychosocial questionnaires. During the endurance tests, surface electromyography signals of the internal obliques, the external obliques, the lumbar multifidus and the iliocostalis were recorded. Patients were dichotomized as underperformers and good performers, by comparing their real endurance time, to the expected time of endurance derived from the normalized median frequency slope. Independent t-tests were performed to examine the differences on the outcome of the questionnaires. In the back muscle endurance test, the underperformers had significantly lower (p<0.05) scores on some of the physical subscales of the SF-36. The underperformers group of the AE test scored significantly higher on the DRAM MZDI (p=0.018) and on the PCS scale (p=0.020) and showed also significantly lower scores on the SF-36 (p<0.05). Back muscle endurance tests are influenced by physical components, while abdominal endurance tests seem influenced by psychosocial components. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nitric oxide alterations following acute ductal constriction in the fetal lamb: a role for superoxide

PubMed Central

Hsu, Jong-Hau; Oishi, Peter; Wiseman, Dean A.; Hou, Yali; Chikovani, Omar; Datar, Sanjeev; Sajti, Eniko; Johengen, Michael J.; Harmon, Cynthia; Black, Stephen M.

2010-01-01

Acute partial compression of the fetal ductus arteriosus (DA) results in an initial abrupt increase in pulmonary blood flow (PBF), which is followed by a significant reduction in PBF to baseline values over the ensuing 2–4 h. We have previously demonstrated that this potent vasoconstricting response is due, in part, to an endothelin-1 (ET-1)-mediated decrease in nitric oxide synthase (NOS) activity. In addition, in vitro data demonstrate that ET-1 increases superoxide levels in pulmonary arterial smooth muscle cells and that oxidative stress alters NOS activity. Therefore, the objectives of this study were to determine the potential role of superoxide in the alterations of hemodynamics and NOS activity following acute ductal constriction in the late-gestation fetal lamb. Eighteen anesthetized near-term fetal lambs were instrumented, and a lung biopsy was performed. After a 48-h recovery, acute constriction of the DA was performed by inflating a vascular occluder. Polyethylene glycol-superoxide dismutase (PEG-SOD; 1,000–1,500 units/kg, n = 7) or PEG-alone (vehicle control group, n = 5) was injected into the pulmonary artery before ductal constriction. Six animals had a sham operation. In PEG-alone-treated lambs, acute ductal constriction rapidly decreased pulmonary vascular resistance (PVR) by 88%. However, by 4 h, PVR returned to preconstriction baseline. This vasoconstriction was associated with an increase in lung superoxide levels (82%), a decrease in total NOS activity (50%), and an increase in P-eNOS-Thr495 (52%) (P < 0.05). PEG-SOD prevented the increase of superoxide after ductal constriction, attenuated the vasoconstriction, preserved NOS activity, and increased P-eNOS Ser1177 (307%, P < 0.05). Sham procedure induced no changes. These data suggest that an acute decrease in NOS activity that is mediated, in part, by increased superoxide levels, and alterations in the phosphorylation status of the endothelial NOS isoform, underlie the pulmonary vascular response to acute ductal constriction. PMID:20363848

Pupil constriction evoked in vitro by stimulation of the oculomotor nerve in the turtle (Trachemys scripta elegans).

PubMed

Dearworth, James R; Brenner, J E; Blaum, J F; Littlefield, T E; Fink, D A; Romano, J M; Jones, M S

2009-01-01

The pond turtle (Trachemys scripta elegans) exhibits a notably sluggish pupillary light reflex (PLR), with pupil constriction developing over several minutes following light onset. In the present study, we examined the dynamics of the efferent branch of the reflex in vitro using preparations consisting of either the isolated head or the enucleated eye. Stimulation of the oculomotor nerve (nIII) using 100-Hz current trains resulted in a maximal pupil constriction of 17.4% compared to 27.1% observed in the intact animal in response to light. When current amplitude was systematically increased from 1 to 400 microA, mean response latency decreased from 64 to 45 ms, but this change was not statistically significant. Hill equations fitted to these responses indicated a current threshold of 3.8 microA. Stimulation using single pulses evoked a smaller constriction (3.8%) with response latencies and threshold similar to that obtained using train stimulation. The response evoked by postganglionic stimulation of the ciliary nerve using 100-Hz trains was largely indistinguishable from that of train stimulation of nIII. However, application of single-pulse stimulation postganglionically resulted in smaller pupil constriction at all current levels relative to that of nIII stimulation, suggesting that there is amplification of efferent drive at the ganglion. Time constants for constrictions ranged from 88 to 154 ms with relaxations occurring more slowly at 174-361 ms. These values for timing from in vitro are much faster than the time constant 1.66 min obtained for the light response in the intact animal. The rapid dynamics of pupil constriction observed here suggest that the slow PLR of the turtle observed in vivo is not due to limitations of the efferent pathway. Rather, the sluggish response probably results from photoreceptive mechanisms or central processing.

Prevalence of abnormal lactose breath hydrogen tests in children with functional abdominal pain.

PubMed

Garg, Neha; Basu, Srikanta; Singh, Preeti; Kumar, Ruchika; Sharma, Lokesh; Kumar, Praveen

2017-05-01

The study was undertaken to determine the prevalence of abnormal lactose breath hydrogen test in children with non-organic chronic abdominal pain. Children with chronic abdominal pain were examined and investigated for organic causes. All children without a known organic cause underwent lactose and glucose breath hydrogen test. After a standard dose of 2 g/kg of lactose to a maximum of 50 g, hydrogen in breath was measured at 15 min intervals for 3 h. A rise of 20 ppm above baseline was considered suggestive of lactose malabsorption. Of 108 children screened, organic causes were found in 46 children. Sixty-two patients without any organic cause underwent hydrogen breath test. Lactose hydrogen breath test (HBT) was positive in 36 of 62 (58%), while 11 (17%) had positive HBT with glucose suggestive of small intestinal bacterial overgrowth (SIBO). Twenty out of 34 (59%) improved on lactose free diet while 8 out of 11 (72%) children of SIBO improved on antibiotics. Lactose malabsorption was seen in 58% of children with non-organic chronic abdominal pain.

Enhanced magnetocaloric effect material

DOEpatents

Lewis, Laura J. H.

2006-07-18

A magnetocaloric effect heterostructure having a core layer of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, and a constricting material layer coated on at least one surface of the magnetocaloric material core layer. The constricting material layer may enhance the magnetocaloric effect by restriction of volume changes of the core layer during application of a magnetic field to the heterostructure. A magnetocaloric effect heterostructure powder comprising a plurality of core particles of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, wherein each of the core particles is encapsulated within a coating of a constricting material is also disclosed. A method for enhancing the magnetocaloric effect within a giant magnetocaloric material including the step of coating a surface of the magnetocaloric material with a constricting material is disclosed.

Electrophysiology of Axonal Constrictions

NASA Astrophysics Data System (ADS)

Johnson, Christopher; Jung, Peter; Brown, Anthony

2013-03-01

Axons of myelinated neurons are constricted at the nodes of Ranvier, where they are directly exposed to the extracellular space and where the vast majority of the ion channels are located. These constrictions are generated by local regulation of the kinetics of neurofilaments the most important cytoskeletal elements of the axon. In this paper we discuss how this shape affects the electrophysiological function of the neuron. Specifically, although the nodes are short (about 1 μm) in comparison to the distance between nodes (hundreds of μm) they have a substantial influence on the conduction velocity of neurons. We show through computational modeling that nodal constrictions (all other features such as numbers of ion channels left constant) reduce the required fiber diameter for a given target conduction velocity by up to 50% in comparison to an unconstricted axon. We further show that the predicted optimal fiber morphologies closely match reported fiber morphologies. Supported by The National Science Foundation (IOS 1146789)

Hyperenhancement of the Pericardium on Cardiac Magnetic Resonance Imaging: A Marker of Acute Inflammation and Neovascularization or a Chronic Fibrotic State.

PubMed

Mullen, Liam; Chew, Pei Gee; Frost, Frederick; Ahmed, Ayesha; Khand, Aleem

2016-01-01

In cardiac magnetic resonance imaging, hyperenhancement of the pericardium post gadolinium administration in acute chest pain often signifies pericarditis with an acute inflammatory response and neovascularization. In the context of constrictive pericarditis, case series have indicated that the intensity of hyperenhancement and the thickness of the pericardium imply reversibility of the physiology of the constrictive pericarditis. We present a case of intense hyperenhancement and marked thickening of the pericardium in a patient with constrictive pericarditis with antecedent chest pain. Surgical resection of the pericardium and microscopy revealed a chronic fibrotic state with no evidence of inflammation or neovascularization, thus clarifying the failure of initial medical/anti-inflammatory treatment. Our case highlights the fact that hyperenhancement of the pericardium post gadolinium is non-specific for histology and does not necessarily imply the reversibility of pericardial constriction. © 2016 S. Karger AG, Basel.

Pupillary Response and Phenotype in ASD: Latency to Constriction Discriminates ASD from Typically Developing Adolescents.

PubMed

Lynch, Georgina T F; James, Stephen M; VanDam, Mark

2018-02-01

Brain imaging data describe differences in the ASD brain, including amygdala overgrowth, neural interconnectivity, and a three-phase model of neuroanatomical changes from early post-natal development through late adolescence. The pupil reflex test (PRT), a noninvasive measure of brain function, may help improve early diagnosis and elucidate underlying physiology in expression of ASD endophenotype. Commonly observed characteristics of ASD include normal visual acuity but difficulty with eye gaze and photosensitivity, suggesting deficient neuromodulation of cranial nerves. Aims of this study were to confirm sensitivity of the PRT for identifying adolescents with ASD, determine if a phenotype for a subtype of ASD marked by pupil response is present in adolescence, and determine whether differences could be observed on a neurologic exam testing cranial nerves II and III (CNII; CNIII). Using pupillometry, constriction latency was measured serving as a proxy for recording neuromodulation of cranial nerves underlying the pupillary reflex. The swinging flashlight method, used to perform the PRT for measuring constriction latency and return to baseline, discriminated ASD participants from typically developing adolescents on 72.2% of trials. Results further confirmed this measure's sensitivity within a subtype of ASD in later stages of development, serving as a correlate of neural activity within the locus-coeruleus norepinephrine (LC-NE) system. A brainstem model of atypical PRT in ASD is examined in relation to modulation of cranial nerves and atypical arousal levels subserving the atypical pupillary reflex. Autism Res 2018, 11: 364-375. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Milder forms of autism spectrum disorder (ASD) can be difficult to diagnose based on behavioral testing alone. This study used eye-tracking equipment and a hand-held penlight to measure the pupil reflex in adolescents with "high functioning" ASD and in adolescents without ASD. The ASD group showed a delay in pupil response. This is the first eye-tracking study to conduct this test as typically performed by a clinical provider, demonstrating differences in older individuals with a subtype of ASD. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Evaluation of Criteria Associated with Abdominal Fitness Testing.

ERIC Educational Resources Information Center

Robertson, Loarn D.; Magnusdottir, Hjordis

1987-01-01

The use of the timed sit up as a measure of abdominal fitness has been challenged. This article describes experiments designed to evaluate a modified curl up test as an alternative. Subjects were 20 college students averaging 25.3 years of age. Results are discussed. (Author/MT)

Effect of styrene maleic acid WIN55,212-2 micelles on neuropathic pain in a rat model.

PubMed

Linsell, Oliver; Brownjohn, Philip W; Nehoff, Hayley; Greish, Khaled; Ashton, John C

2015-05-01

Cannabinoid receptor agonists are moderately effective at reducing neuropathic pain but are limited by psychoactivity. We developed a styrene maleic acid (SMA) based on the cannabinoid WIN 55,212-2 (WIN) and tested in a rat model of neuropathic pain and in the rotarod test. We hypothesized that miceller preparation can ensure prolonged plasma half-life being above the renal threshold of excretion. Furthermore, SMA-WIN could potentially reduce the central nervous system effects of encapsulated WIN by limiting its transport across the blood-brain barrier. Using the chronic constriction injury model of sciatic neuropathy, the SMA-WIN micelles were efficacious in the treatment of neuropathic pain for a prolonged period compared to control (base WIN). Attenuation of chronic constriction injury-induced mechanical allodynia occurred for up to 8 h at a dose of 11.5 mg/kg of SMA-WIN micelles. To evaluate central effects on motor function, the rotarod assessment was utilized. Results showed initial impairment caused by SMA-WIN micelles to be identical to WIN control for up to 1.5 h. Despite this, the SMA-WIN micelle formulation was able to produce prolonged analgesia over a time when there was decreased impairment in the rotarod test compared with base WIN.

A Preliminary Videofluoroscopic Investigation of Swallowing Physiology and Function in Individuals with Oculopharyngeal Muscular Dystrophy (OPMD).

PubMed

Waito, Ashley A; Steele, Catriona M; Peladeau-Pigeon, Melanie; Genge, Angela; Argov, Zohar

2018-05-03

Dysphagia is one of the primary symptoms experienced by individuals with Oculopharyngeal Muscular Dystrophy (OPMD). However, we lack understanding of the discrete changes in swallowing physiology that are seen in OPMD, and the resulting relationship to impairments of swallowing safety and efficiency. This study sought to describe the pathophysiology of dysphagia in a small sample of patients with OPMD using a videofluoroscopy examination (VFSS) involving 3 × 5 mL boluses of thin liquid barium (22% w/v). The aim of this study is to extend what is known about the pathophysiology of dysphagia in OPMD, by quantifying changes in swallow timing, kinematics, safety, and efficiency, measured from VFSS. This study is a secondary analysis of baseline VFSS collected from 11 adults (4 male), aged 48-62 (mean 57) enrolled in an industry-sponsored phase 2 therapeutic drug trial. Blinded raters scored the VFSS recordings for safety [Penetration-Aspiration Scale (PAS)], efficiency [Normalized Residue Ratio Scale (NRRS)], timing [Pharyngeal Transit Time (PTT), Swallow Reaction Time (SRT), Laryngeal Vestibule Closure Reaction Time (LVCrt), Upper Esophageal Sphincter Opening Duration (UESD)], and kinematics (hyoid movement, pharyngeal constriction, UES opening width). Impairment thresholds from existing literature were defined to characterize swallowing physiology and function. Further, Fisher's Exact tests and Pearson's correlations were used to conduct a preliminary exploration of associations between swallowing physiology (e.g., kinematics, timing) and function (i.e., safety, efficiency). Compared to published norms, we identified significant differences in the degree of maximum pharyngeal constriction, hyoid movement distance and speed, as well as degree and timeliness of airway closure. Unsafe swallowing (PAS ≥ 3) was seen in only 3/11 patients. By contrast, clinically significant residue (i.e., NRRS scores ≥ 0.09 vallecular; ≥ 0.2 pyriform) was seen in 7/11 patients. Fisher's Exact tests revealed associations between prolonged SRT, PTT, and unsafe swallowing. Weak associations were also identified between post-swallow residue and poor pharyngeal constriction during the swallow. Detailed analysis of swallowing physiology in this series of adults with OPMD aligns with impaired muscular function (e.g., reduced pharyngeal constriction, incomplete laryngeal vestibule closure) associated with the disease, and primary functional challenges with swallow efficiency. Further work is needed to explore a greater range of food and liquid textures, and to identify additional physiological mechanisms underlying swallowing impairment in OPMD.

Abdominal emergencies in pediatrics.

PubMed

Coca Robinot, D; Liébana de Rojas, C; Aguirre Pascual, E

2016-05-01

Abdominal symptoms are among the most common reasons for pediatric emergency department visits, and abdominal pain is the most frequently reported symptom. Thorough history taking and physical examination can often reach the correct diagnosis. Knowing the abdominal conditions that are most common in each age group can help radiologists narrow the differential diagnosis. When imaging tests are indicated, ultrasonography is usually the first-line technique, enabling the diagnosis or adding relevant information with the well-known advantages of this technique. Nowadays, plain-film X-ray studies are reserved for cases in which perforation, bowel obstruction, or foreign body ingestion is suspected. It is also important to remember that abdominal pain can also occur secondary to basal pneumonia. CT is reserved for specific indications and in individual cases, for example, in patients with high clinical suspicion of abdominal disease and inconclusive findings at ultrasonography. We review some of the most common conditions in pediatric emergencies, the different imaging tests indicated in each case, and the imaging signs in each condition. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Mild mitral and tricuspid regurgitation secondary to pericardial constriction.

PubMed

Mittal, S R

2014-06-01

A 26 years female presented with pericardial effusion. On follow up she developed pericardial constriction with new appearance of mild mitral and tricuspid regurgitation without any other pathology. Fibrosis along posterior atrioventricular groove could be responsible for regurgitation.

Antinociceptive effect of the aqueous extract obtained from roots of Physalis angulata L. on mice.

PubMed

Bastos, G N T; Santos, A R S; Ferreira, V M M; Costa, A M R; Bispo, C I; Silveira, A J A; Do Nascimento, J L M

2006-01-16

In this study, we attempted to identify the possible antinociceptive action of aqueous extract (AE) obtained from roots of Physalis angulata, known in Brazil as "Camapu", used to treat various pain-related physiological conditions. The AE of Physalis angulata (10-30 mg/kg) given by i.p. or p.o. route, 0.5 and 1h prior, produced significant inhibition of abdominal constrictions caused by acetic acid, with ID(50) values of 18.5 (17.4-19.8) and 21.5 (18.9-24.4)mg/kg and inhibitions of 83+/-8 and 66+/-5%, respectively. The AE (10-60 mg/kg, i.p.) also caused significant inhibition of the late-phase of formalin-induced pain, with an ID(50) value of 20.8 (18.4-23.4)mg/kg and inhibition of 100%. Treatment of mice with AE (60 mg/kg, i.p.) or with morphine (10mg/kg, i.p.) produced a significant increase of the reaction time in the hot-plate test. These results demonstrate, for the first time, that the AE of Physalis angulata produce marked antinociception against the acetic acid-induced visceral pain and inflammatory pain responses induced by formalin in mice. The mechanism by which the AE produces antinociception still remains unclear. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive action and also to identify the active principles present in Physalis angulata. Moreover, the antinociceptive action demonstrated in the present study supports, at least partly, the ethnomedical uses of this plant.

Bioimpedance to screen for abdominal fat in patients with breast cancer treatment-related lymphedema.

PubMed

de Fátima Guerreiro Godoy, Maria; Silva, Edivandra Buzato; de Godoy, Jose Maria Pereira

2016-07-28

One of the dreaded complications after the treatment of breast cancer is lymphedema. Therapies used in the treatment of breast cancer such as surgery, radiotherapy, hormone therapy and chemotherapy may be adversely affected by obesity. The objective of this study was to use bioimpedance to assess abdominal fat in women with breast cancer treatment-related lymphedema and suggest this as a screening method. Forty-five female patients with clinical diagnosis of breast cancer treatment-related lymphedema were evaluated in this quantitative cross-sectional study. A control group, composed of 38 patients with varicose veins and women attending a social support group, was matched for age and body mass index (BMI). All participants were submitted to a bioimpedance evaluation (In Body S 10), with particular attention being paid to abdominal fat and their BMI. The unpaired t -test, Fisher Exact test and Mann-Whitney test were used for statistical analysis and an alpha error of 5%. There was no significant difference (p -value = 0.23) in the mean BMI between the study group (27.79 kg∕m2) and the control group (28.80 kg∕m2). The mean abdominal circumference, a measure of abdominal fat, of the women in the study group was 130.54 cm2 and for the control group it was 102.24 cm2 (p -value = 0.0037). Thus the study group had more abdominal fat (p -value = 0.0003). Moreover, on comparing obese patients in the two groups, the study group had more abdominal fat (p -value = 0.02). However, no significant difference was observed comparing non-obese patients (p -value = 0.6). The comparison of obese patients with non-obese patients in the control group identifies an association between obesity and abdominal fat (p -value < 0.04). Overweight and obese women with breast cancer treatment-related lymphedema are more likely to have increased abdominal fat than the general population with bioimpedance.

Subacute constrictive pericarditis from Serratia marcescens bacteremia.

PubMed

Khan, M Y

1983-12-01

A case report of subacute constrictive pericarditis associated with disseminated Serratia marcescens infection and bacteremia in a patient with chronic tubulointerstitial nephritis and uremia is described. Although not substantiated by clinical history, the renal pathologic features were similar to those of ethylene glycol-induced tubulointerstitial nephritis. The patient did not have a history of heroin addiction. The importance of predisposing factors such as uremia, invasive vascular procedures, tracheal intubation, peritoneal dialysis, and pericardiocentesis in Serratia infection in susceptible persons is discussed, as are possible roles of uremia, pericardiocentesis, and pericardiotomy in the pathogenesis of constrictive pericarditis in the present case.

Fabricated autologous epidermal cell sheets for the prevention of esophageal stricture after circumferential ESD in a porcine model.

PubMed

Kanai, Nobuo; Yamato, Masayuki; Ohki, Takeshi; Yamamoto, Masakazu; Okano, Teruo

2012-10-01

Endoscopic submucosal dissection (ESD) is an accepted treatment for early esophageal carcinoma. However, resection of a large mucosal area, as with circumferential ESD, induces severe stricture formation. To evaluate the efficacy of cultured autologous epidermal cell sheets to prevent severe esophageal constriction after circumferential ESD. Animal study. University institute. Eight pigs underwent circumferential esophageal ESD while under general anesthesia. In 4 pigs, fabricated autologous epidermal cell sheets were endoscopically transplanted to the central ESD sites immediately after the ESD. The other 4 pigs underwent circumferential ESD only. Necropsy and histological assessment were performed at 1 and 2 weeks post-ESD. Weight gain, degree of mucosal constriction, and histological assessments. All pigs in the control group showed severe esophageal constriction after 2 weeks. The control and transplanted groups had weight gains of -10.3% and 0.3% (P = .03), respectively, and the mean degrees of constriction were 88% and 56% (P < .01), respectively. Early re-epithelialization and mild fibrosis in the muscularis were observed in the transplanted group. Animal study, small sample size. Fabricated autologous skin epidermal cell sheets would be useful in preventing severe esophageal constriction after circumferential ESD. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Strategic obstacle placement reduces drop breakup probability in concentrated emulsion flowing into a constriction

NASA Astrophysics Data System (ADS)

Khor, Jian Wei; Hua, Yu; Bick, Alison; Tang, Sindy

2017-11-01

In this study, we investigate the effect of an obstacle on the breakup probability of droplets within a concentrated emulsion flowing into a constriction. We introduce a concentrated emulsion as a 2D monolayer through a tapered channel into a narrow constriction. This geometry is commonly used for the serial interrogation of droplet content in droplet microfluidics applications. We found that certain drop-drop interactions near the constriction entrance lead to the breakup of these drops at a high flow rates. Such breakup sets the upper limit for the droplet interrogation throughput. Incidentally, previous findings have shown that strategic placement of a circular post near a narrow exit can reduce the conflict from the interactions among living organisms (humans, ants, and sheep) or a cluster of particles when entering a narrow exit. Inspired by these results, we modify the tapered channel by placing a circular post in a strategic location near the constriction entrance in order to reduce catastrophic drop-drop interactions and to avoid breakup. Preliminary work shows that the circular posts can reduce the breakup fraction of drops by up to 17%. The optimization of the location and size of the obstacle is expected to further reduce the breakup fraction.

Selection on bristle length has the ability to drive the evolution of male abdominal appendages in the sepsid fly Themira biloba.

PubMed

Herath, B; Dochtermann, N A; Johnson, J I; Leonard, Z; Bowsher, J H

2015-12-01

Many exaggerated and novel traits are strongly influenced by sexual selection. Although sexual selection is a powerful evolutionary force, underlying genetic interactions can constrain evolutionary outcomes. The relative strength of selection vs. constraint has been a matter of debate for the evolution of male abdominal appendages in sepsid flies. These abdominal appendages are involved in courtship and mating, but their function has not been directly tested. We performed mate choice experiments to determine whether sexual selection acts on abdominal appendages in the sepsid Themira biloba. We tested whether appendage bristle length influenced successful insemination by surgically trimming the bristles. Females paired with males that had shortened bristles laid only unfertilized eggs, indicating that long bristles are necessary for successful insemination. We also tested whether the evolution of bristle length was constrained by phenotypic correlations with other traits. Analyses of phenotypic covariation indicated that bristle length was highly correlated with other abdominal appendage traits, but was not correlated with abdominal sternite size. Thus, abdominal appendages are not exaggerated traits like many sexual ornaments, but vary independently from body size. At the same time, strong correlations between bristle length and appendage length suggest that selection on bristle length is likely to result in a correlated increase in appendage length. Bristle length is under sexual selection in T. biloba and has the potential to evolve independently from abdomen size. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Medical evacuation for unrecognized abdominal wall pain: a case series.

PubMed

Msonda, Hapu T; Laczek, Jeffrey T

2015-05-01

Chronic abdominal pain is a frequently encountered complaint in the primary care setting. The abdominal wall is the etiology of this pain in 10 to 30% of all cases of chronic abdominal pain. Abdominal cutaneous nerve entrapment at the lateral border of the rectus abdominis muscle has been attributed as a cause of this pain. In the military health care system, patients with unexplained abdominal pain are often transferred to military treatment facilities via the Military Medical Evacuation (MEDEVAC) system. We present two cases of patients who transferred via MEDEVAC to our facility for evaluation and treatment of chronic abdominal pain. Both patients had previously undergone extensive laboratory evaluation, imaging, and invasive procedures, such as esophagogastroduodenoscopy before transfer. Upon arrival, history and physical examinations suggested an abdominal wall source to their pain, and both patients experienced alleviation of their abdominal wall pain with lidocaine and corticosteroid injection. This case series highlights the need for military physicians to be aware of abdominal wall pain. Early diagnosis of abdominal cutaneous nerve entrapment syndrome by eliciting Carnett's sign will limit symptom chronicity, avoid unnecessary testing, and even prevent medical evacuation. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Abdominal CT scan

MedlinePlus

Computed tomography scan - abdomen; CT scan - abdomen; CT abdomen and pelvis ... An abdominal CT scan makes detailed pictures of the structures inside your belly very quickly. This test may be used to look ...

Superoxide differentially controls pulmonary and systemic vascular tone through multiple signalling pathways

PubMed Central

Snetkov, Vladimir A.; Smirnov, Sergey V.; Kua, Justin; Aaronson, Philip I.; Ward, Jeremy P.T.; Knock, Greg A.

2011-01-01

Aims The aim of this study was to determine the relative importance of Ca2+ sensitization, ion channels, and intracellular Ca2+ ([Ca2+]i) in the mixed constrictor/relaxation actions of superoxide anion on systemic and pulmonary arteries. Methods and results Pulmonary and mesenteric arteries were obtained from rat. Superoxide was generated in arteries and cells with 6-anilino-5,8-quinolinequinone (LY83583). Following pre-constriction with U46619, 10 μmol/L LY83583 caused constriction in pulmonary and relaxation in mesenteric arteries. Both constrictor and relaxant actions of LY83583 were inhibited by superoxide dismutase and catalase. LY83583 caused Rho-kinase-dependent constriction in α-toxin-permeabilized pulmonary but not mesenteric arteries. Phosphorylation of myosin phosphatase-targeting subunit-1 (MYPT-1; as determined by western blot), was enhanced by LY83583 in pulmonary artery only. However, in both artery types, changes in tension were closely correlated with changes in phosphorylation of the 20 kDa myosin light chain as well as changes in [Ca2+]i (as measured with Fura PE-3), with LY83583 causing increases in pulmonary and decreases in mesenteric arteries. When U46619 was replaced by 30 mmol/L K+, all changes in [Ca2+]i were abolished and LY83583 constricted both artery types. The KV channel inhibitor 4-aminopyridine abolished the LY83583-induced relaxation in mesenteric artery without affecting constriction in pulmonary artery. However, LY83583 caused a similar hyperpolarizing shift in the steady-state activation of KV current in isolated smooth muscle cells of both artery types. Conclusions Superoxide only causes Rho-kinase-dependent Ca2+ sensitization in pulmonary artery, resulting in constriction, and whilst it opens KV channels in both artery types, this only results in relaxation in mesenteric. PMID:20805095

Evaluation of hawthorn extract on immunomodulatory biomarkers in a pressure overload model of heart failure.

PubMed

Bleske, Barry E; Zineh, Issam; Hwang, Hyun Seok; Welder, Gregory J; Ghannam, Michael M J; Boluyt, Marvin O

2007-12-01

Hawthorn extract (Crataegeus sp.) a botanical complementary and alternative medicine is often used to treat heart failure. The mechanism(s) by which hawthorn extract may treat heart failure is unknown but may include, theoretically, immunological effects. Therefore, the purpose of this study is to determine the effect of hawthorn extract on the immunomodulatory response in a pressure overload model of heart failure. A total of 62 male Sprague-Dawley rats were randomized to either aortic constriction + vehicle (AC; n=15), aortic constriction + hawthorn 1.3 mg/kg (HL, n=17), aortic constriction + hawthorn 13 mg/kg (HM, n=15), or aortic constriction + hawthorn 130 mg/kg (HH, n=15). Six months after surgical procedure animals were sacrificed and plasma samples obtained for the measurement of the following immunomodulatory markers: interleukin (IL) IL-1ss, IL-2, IL-6, IL-10; and leptin. The mortality rate following 6 months of aortic constriction was 40% in the AC group compared to 41%, 60%, and 53% for the HL, HM, and HH groups respectively (P>0.05 compared to AC). Aortic constriction produced a similar increase in the left ventricle/body weight ratio for all groups. Hawthorn extract had no effect on the immunomodulatory markers measured in this study, although there appeared to be a trend suggesting suppression of IL-2 plasma concentrations. In this animal model of heart failure, hawthorn extract failed to significantly affect the immunomodulatory response characterized after 6 months of pressure overload at a time when approximately 50% mortality was exhibited. Mechanisms other than immunological may better define hawthorn's effect in treating heart failure.

The Cerrillos Uplift, the La Bajada Constriction, and Hydrogeologic Framework of the Santo Domingo Basin, Rio Grande Rift, New Mexico

USGS Publications Warehouse

Minor, Scott A.

2006-01-01

The geologic, geophysical, and hydrogeologic properties of the La Bajada constriction and Santo Domingo Basin, northern New Mexico, result from tectonic and volcanic processes of the late Tertiary and Quaternary Rio Grande rift. An integrated geologic and geophysical assessment in the La Bajada constriction allows development of a geologic framework that can provide input for regional ground-water flow models. These models then can provide better estimates of future water supplies in a region that largely subsists on aquifers in Rio Grande rift basins. The combination of surface geologic investigations (stratigraphic and structural studies; chapters A, B, C, and E), airborne geophysics (aeromagnetic and time-domain electromagnetic surveys; chapters D and F), ground geophysical measurements (gravity and magnetotelluric surveys; chapters D and F), and data from the few wells in the area (chapter G) provides new constraints on the hydrogeologic framework of this area. Summary results of our investigations are synthesized in chapter G. Through-going aquifers consisting of ancestral Rio Grande axial-river sand and gravel and of coarse western-piedmont gravel form the predominant ground-water pathways through the partly buried structural trough defining the La Bajada constriction between Espa?ola and Santo Domingo Basins. Thick, clay-rich Cretaceous marine shales of low hydraulic conductivity form a pervasive regional confining unit within the Cerrillos uplift on the southeast flank of the constriction. Numerous, dominantly north-northwest-striking, intrabasin faults that project part way across the La Bajada constriction create a matrix of laterally and vertically variable hydrogeologic compartments that locally partition and deflect ground-water flow parallel to faults.

The role of Rho-kinase and calcium ions in constriction triggered by ET-1.

PubMed

Wiciński, Michał; Szadujkis-Szadurska, Katarzyna; Węclewicz, Mateusz M; Malinowski, Bartosz; Matusiak, Grzegorz; Walczak, Maciej; Wódkiewicz, Eryk; Grześk, Grzegorz; Pawlak-Osińska, Katarzyna

2018-05-05

Endothelin-1 (ET-1) is one of the key factors regulating tension of smooth muscles in blood vessels. It is believed that ET-1 plays an important role in pathogenesis of hypertension, and cardiovascular diseases; therefore, research in order to limit ET-1-mediated action is still in progress. The main objective of this paper was to evaluate the role of Rho-kinase in the ET-1-induced constriction of arteries. The analysis also included significance of intra- and extracellular pool of calcium ions in constriction triggered by ET-1. The studies were performed on perfused Wistar rat tail arteries. Concentration response curve (CRC) was determined for ET-1 in the presence of increased concentrations of Rho-kinase inhibitor (Y-27632) and IP3-receptor antagonist (2APB), both in reference to constriction triggered by solely ET-1. Afterwards, the influence of calcium ions present in the perfusion fluid was evaluated in terms of the effect triggered by 2APB and occurring in arteries constricted by ET-1. ET-1, in concentration dependent manner, leads to increase in perfusion pressure. Y-27632 and 2APB lead to shift of the concentration response curve for ET-1 to the right with simultaneously lowered maximum effect. There was no difference in reaction of the artery constricted by ET-1 and treated with 2APB in solution containing calcium and in calcium-free solution. Vasoconstrictive action of endothelin is not significantly dependent on the inflow of extracellular calcium, but it is proportional to inflow of Ca 2+ related to activation of IP3 receptors and to Rho-kinase activity. Copyright © 2018. Published by Elsevier Inc.

Co-occurrence of carbohydrate malabsorption and primary epiploic appendagitis

PubMed Central

Schnedl, Wolfgang J; Kalmar, Peter; Mangge, Harald; Krause, Robert; Wallner-Liebmann, Sandra J

2015-01-01

Unspecific abdominal complaints including bloating and irregular bowel movements may be caused by carbohydrate malabsorption syndromes, e.g., lactose and fructose malabsorption. These symptoms were investigated with hydrogen (H2) breath tests and correlated to carbohydrate malabsorption. During performing these H2-breath tests the patient presented with an acute, localized, non-migratory pain in the left lower abdominal quadrant. Primary epiploic appendagitis is a rare cause of abdominal acute or subacute complaints and diagnosis of primary epiploic appendagitis (PEA) is made when computed tomography reveals a characteristic lesion. We report on a patient with co-occurrence of lactose and fructose malabsorption, which was treated successfully with a diet free of culprit carbohydrates, with PEA recovering without medication or surgical treatment within few days. Since the abdominal unspecific symptoms had been present for months, they appeared not to be correlated to the acute localized abdominal pain, therefore we speculate on a random co-occurrence of combined carbohydrate malabsorption and PEA. PMID:26401090

Medical Versus Interventional Treatment of Intra-Abdominal Abscess in Patients With Crohn Disease.

PubMed

Graham, Emily; Rao, Krishna; Cinti, Sandro

2017-01-01

Few studies exist to guide the treatment approach to intra-abdominal abscesses in Crohn disease, which can include antimicrobials alone or in conjunction with percutaneous drainage or surgery. The primary aim of this study is to review outcomes from different treatment approaches to intra-abdominal abscess in Crohn disease. Medical records were reviewed for patients admitted to the University of Michigan health care system with Crohn disease and intra-abdominal abscess over a 4-year period. Outcomes were compared among medical and interventional approaches. The χ 2 test was used to test for statistical significance. Of the 33 patients included, 13 were in the medical group and 20 were in the interventional group. Abscess recurrence/nonresolution occurred in 31% of patients in the medical group and 25% of patients in the interventional group ( P = .7). In this study, there was no significant difference in outcome between medical and interventional therapy for intra-abdominal abscess in Crohn disease.

The effects of nursing activities on the intra-abdominal pressure of patients at risk for intra-abdominal hypertension.

PubMed

Lee, Rosemary K

2017-01-01

Intra-abdominal hypertension (IAH) occurs frequently in critically ill patients, and adds to their morbidity and mortality. There is no published evidence on the effects of nursing activities on the intra-abdominal pressure (IAP) for patients at risk of IAH. The purpose of this study was to identify the effects of hygiene care on the IAP of patients at risk for IAH. Hygiene care was provided to 34 at-risk patients. IAP was measured prior to initiating the hygiene care, immediately after and 10 minutes later. This was a quasi-experimental, pre-test/ post-test design. The 10 minute post-hygiene care measurement of the IAP was significantly lower than the pre or immediate post-measurement of the IAP. There were no significant changes in the mean arterial pressure (MAP) or the abdominal perfusion pressure (APP). It is safe and possibly therapeutic to provide hygiene care to patients at risk for IAH.

Eddies in a bottleneck: an arbitrary Debye length theory for capillary electroosmosis.

PubMed

Park, Stella Y; Russo, Christopher J; Branton, Daniel; Stone, Howard A

2006-05-15

Using an applied electrical field to drive fluid flows becomes desirable as channels become smaller. Although most discussions of electroosmosis treat the case of thin Debye layers, here electroosmotic flow (EOF) through a constricted cylinder is presented for arbitrary Debye lengths (kappa(-1)) using a long wavelength perturbation of the cylinder radius. The analysis uses the approximation of small potentials. The varying diameter of the cylinder produces radially and axially varying effective electric fields, as well as an induced pressure gradient. We predict the existence of eddies for certain constricted geometries and propose the possibility of electrokinetic trapping in these regions. We also present a leading-order criterion which predicts central eddies in very narrow constrictions at the scale of the Debye length. Eddies can be found both in the center of the channel and along the perimeter, and the presence of the eddies is a consequence of the induced pressure gradient that accompanies electrically driven flow into a narrow constriction.

Eddies in a Bottleneck: An Arbitrary Debye Length Theory for Capillary Electroosmosis

PubMed Central

Park, Stella Y.; Russo, Christopher J.; Branton, Daniel; Stone, Howard A.

2011-01-01

Using an applied electrical field to drive fluid flows becomes desirable as channels become smaller. Although most discussions of electroosmosis treat the case of thin Debye layers, here electroosmotic flow (EOF) through a constricted cylinder is presented for arbitrary Debye lengths (κ−1) using a long wavelength perturbation of the cylinder radius. The analysis uses the approximation of small potentials. The varying diameter of the cylinder produces radially and axially varying effective electric fields, as well as an induced pressure gradient. We predict the existence of eddies for certain constricted geometries and propose the possibility of electrokinetic trapping in these regions. We also present a leading-order criterion which predicts central eddies in very narrow constrictions at the scale of the Debye length. Eddies can be found both in the center of the channel and along the perimeter, and the presence of the eddies is a consequence of the induced pressure gradient that accompanies electrically driven flow into a narrow constriction. PMID:16376361

The 1983 hydraulic jump in Crystal Rapid: implications for river- running and geomorphic evolution in the Grand Canyon.

USGS Publications Warehouse

Kieffer, S.W.

1985-01-01

At Crystal Creek, a debris fan was emplaced in 1966, constricting the channel of the Colorado River to about 0.25 of its upstream width between 1967 and 1983, forming a major rapid. The hydraulics of Crystal Creek rapid are described, and an analysis is presented to support the hypothesis that the major wave in the rapid was a normal wave (one type of hydraulic jump). Hydraulic jumps rarely occur in natural river channels with erodible beds, but one was present at Crystal Rapid because of the unusually severe constriction of the Colorado River by the 1966 debris fan. A quantitative model for river debris fan shapes is proposed and is used to estimate prehistoric flood levels from the observed constrictions: the 0.5 value of river constriction found at the more mature debris fans in the Grand Canyon suggests that peak flood discharges of approximately 11 320 m3/s have occurred. -from Author

Effusive-constrictive pericarditis as the manifestation of an unexpected diagnosis.

PubMed

Marta, Liliana; Alves, Miguel; Peres, Marisa; Ferreira, Ricardo; Ferreira, Hugo; Leal, Margarida; Nobre, Ângelo

2015-01-01

Constrictive pericarditis is a clinical condition characterized by the appearance of signs and symptoms of right heart failure due to loss of pericardial compliance. Cardiac surgery is now one of the most frequent causes in developed countries, while tuberculosis remains the most prevalent cause in developing countries. Malignancy is a rare cause but usually has a poor prognosis. The diagnosis of constrictive pericarditis remains a clinical challenge and requires a combination of noninvasive diagnostic methods (echocardiography, cardiac magnetic resonance and computed tomography); in some cases, cardiac catheterization is needed to confirm the diagnosis. The authors present the case of a 51-year-old man, hospitalized due to cardiac tamponade. Diagnostic investigation was suggestive of tuberculous etiology. Despite directed medical therapy, the patient developed effusive-constrictive physiology. He underwent pericardiectomy and anatomopathologic study suggested a neoplastic etiology. The patient died in the postoperative period from biventricular failure. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Microfluidic model experiments on the injectability of monoclonal antibody solutions

NASA Astrophysics Data System (ADS)

Duchene, Charles; Filipe, Vasco; Nakach, Mostafa; Huille, Sylvain; Lindner, Anke

2017-11-01

Autoinjection devices that allow patients to self-administer medicine are becoming used more frequently; however, this advance comes with an increased need for precision in the injection process. The rare occurrence of protein aggregates in solutions of monoclonal antibodies constitutes a threat to the reliability of such devices. Here we study the flow of protein solutions containing aggregates in microfluidic model systems, mimicking injection devices, to gain fundamental understanding of the catastrophic clogging of constrictions of given size. We form aggregates by mechanically shaking or heating antibody solutions and then inject these solutions into microfluidic channels with varying types of constrictions. Geometrical clogging occurs when aggregates reach the size of the constriction and can in some cases be undone by increasing the applied pressure. We perform systematic experiments varying the relative aggregate size and the flow rate or applied pressure. The mechanical deformation of aggregates during their passage through constrictions is investigated to gain a better understanding of the clogging and unclogging mechanisms.

[Impact of introduction of O2 on the welding arc of gas pool coupled activating TIG].

PubMed

Huang, Yong; Wang, Yan-Lei; Zhang, Zhi-Guo

2014-05-01

In the present paper, Boltzmann plot method was applied to analyze the temperature distributions of the are plasma when the gas pool coupled activating TIG welding was at different coupling degrees with the outer gas being O2. Based on this study of temperature distributions, the changing regularities of are voltage and are appearance were studied. The result shows that compared with traditional TIG welding, the introduction of O2 makes the welding arc constricted slightly, the temperature of the are center build up, and the are voltage increase. When argon being the inner gas, oxygen serving as the outer gas instead of argon makes the are constricted more obviously. When the coupling degree increases from 0 to 2, the temperature of the are center and the are voltage both increase slightly. In the gas pool coupled activating TIG welding the are is constricted not obviously, and the reason why the weld penetration is improved dramatically in the welding of stainless steel is not are constriction.

Diagnosis of Parasitic Diseases

MedlinePlus

... that cause diarrhea, loose or watery stools, cramping, flatulence (gas) and other abdominal illness. CDC recommends that ... that cause diarrhea, loose or watery stools, cramping, flatulence (gas) and other abdominal illness. This test is ...

Perforated peptic ulcer associated with abdominal compartment syndrome.

PubMed

Lynn, Jiun-Jen; Weng, Yi-Ming; Weng, Chia-Sui

2008-11-01

Abdominal compartment syndrome (ACS) is defined as an increased intra-abdominal pressure with adverse physiologic consequences. Abdominal compartment syndrome caused by perforated peptic ulcer is rare owing to early diagnosis and management. Delayed recognition of perforated peptic ulcer with pneumoperitoneum, bowel distension, and decreased abdominal wall compliance can make up a vicious circle and lead to ACS. We report a case of perforated peptic ulcer associated with ACS. A 74-year-old man with old stroke and dementia history was found to have distended abdomen, edema of bilateral legs, and cyanosis. Laboratory tests revealed deterioration of liver and kidney function. Abdominal compartment syndrome was suspected, and image study was arranged to find the cause. The study showed pneumoperitoneum, contrast stasis in heart with decreased caliber of vessels below the abdominal aortic level, and diffuse lymphedema at the abdominal walls. Emergent laparotomy was performed. Perforated peptic ulcer was noted and the gastrorrhaphy was done. The symptoms, and liver and kidney function improved right after emergent operation.

Multidisciplinary emergent removal of a metal penoscrotal constriction device.

PubMed

Nason, G J; Abdelsadek, A H; Foran, A T; O'Malley, K J

2017-03-10

Strangulation of the genital organs is a rare presentation to the emergency department which requires urgent intervention to avoid long term complications. Penoscrotal constriction devices are either used for autoerotic stimulus or to increase sexual performance by maintaining an erection for a longer period. We report a case of a man who presented with penile strangulation following the application of a titanium penoscrotal constriction ring during sexual intercourse seven hours previously. The Fire Brigade department attended with an electric operated angle grinder to facilitate removal of the ring as standard medical equipment (orthopaedic saws, bolt and bone cutters) were insufficient. Fully functional recovery was achieved.

Impending gangrene of fingers by constriction bands of mother's hair mistaken as pernio by parents: A case series of 10 infants.

PubMed

Bhat, Towseef Ahmad; Ali, Zameer; Moten, Tarseem Lal; Sofi, Aabid Hussain; Mir, Furqaan; Gulzar, Amara

2017-01-01

Long harsh winter in Kashmir Valley increase the incidence of pernio in children so much that common people consider every hand swelling as pernio. 10 Infants over two years were brought to our hospital as cases of pernio involving fingers. All the infants came out to be cases of impending gangrene due to mother's hair as constriction bands around fingers. Impending gangrene of fingers in infants due to mother hair as constriction band is very rare. However its symptoms overlap with symptoms of peripheral cold injuries and can be easily mistaken for each other by people.

Symmetry breaking in clogging for oppositely driven particles

NASA Astrophysics Data System (ADS)

Glanz, Tobias; Wittkowski, Raphael; Löwen, Hartmut

2016-11-01

The clogging behavior of a symmetric binary mixture of colloidal particles that are driven in opposite directions through constrictions is explored by Brownian dynamics simulations and theory. A dynamical state with a spontaneously broken symmetry occurs where one species is flowing and the other is blocked for a long time, which can be tailored by the size of the constrictions. Moreover, we find self-organized oscillations in clogging and unclogging of the two species. Apart from statistical physics, our results are of relevance for fields like biology, chemistry, and crowd management, where ions, microparticles, pedestrians, or other particles are driven in opposite directions through constrictions.

Plain abdominal radiography in acute abdominal pain; past, present, and future

PubMed Central

Gans, Sarah L; Stoker, Jaap; Boermeester, Marja A

2012-01-01

Several studies have demonstrated that a diagnosis based solely on a patient’s medical history, physical examination, and laboratory tests is not reliable enough, despite the fact that these aspects are essential parts of the workup of a patient presenting with acute abdominal pain. Traditionally, imaging workup starts with abdominal radiography. However, numerous studies have demonstrated low sensitivity and accuracy for plain abdominal radiography in the evaluation of acute abdominal pain as well as various specific diseases such as perforated viscus, bowel obstruction, ingested foreign body, and ureteral stones. Computed tomography, and in particular computed tomography after negative ultrasonography, provides a better workup than plain abdominal radiography alone. The benefits of computed tomography lie in decision-making for management, planning of a surgical strategy, and possibly even avoidance of negative laparotomies. Based on abundant available evidence, major advances in diagnostic imaging, and changes in the management of certain diseases, we can conclude that there is no place for plain abdominal radiography in the workup of adult patients with acute abdominal pain presenting in the emergency department in current practice. PMID:22807640

Reliability and validity of lumbar and abdominal trunk muscle endurance tests in office workers with nonspecific subacute low back pain.

PubMed

del Pozo-Cruz, Borja; Mocholi, Miguel H; del Pozo-Cruz, Jesus; Parraca, Jose A; Adsuar, Jose C; Gusi, Narcis

2014-01-01

Despite the widespread use of trunk endurance tests, the reliability and validity of these tests in office workers with subacute nonspecific low back pain are unknown. This cross-sectional study involved 190 subjects: 30 men and 42 women without low back pain and 47 men and 71 women with low back pain. All subjects underwent timed prone and supine isometric lumbar and abdominal trunk endurance tests that were performed until subjective fatigue occurred. All subjects also completed the Roland Morris and Oswestry self-reported disability questionnaires. A test-retest study (7 days) was conducted with 31 participants with low back pain from the study. For the abdominal trunk endurance test, males and females with low back pain had mean (SD) values of 62.06 (36.87) and 46.06 (29.28) seconds, respectively, both significantly lower than the asymptomatic workers. For the lumbar test, males and females with low back pain had mean (SD) values of 79.57 (30.66) and 75.49 (28.97) seconds, respectively, again, both significantly lower than the asymptomatic workers. The intraclass correlation coefficients of both tests exceeded 0.90 and the Kappa indices were excellent for both men and women. Receiver-operating curve analyses revealed areas under the curve very close to or exceeding 0.70 for both men and women for both tests. The lumbar and abdominal trunk muscle endurance tests appeared to be reliable and valid measures in office workers with subacute low back pain.

Protective constriction of coronary vein grafts with knitted nitinol

PubMed Central

Moodley, Loven; Franz, Thomas; Human, Paul; Wolf, Michael F.; Bezuidenhout, Deon; Scherman, Jacques; Zilla, Peter

2013-01-01

OBJECTIVES Different flow patterns and shear forces were shown to cause significantly more luminal narrowing and neointimal tissue proliferation in coronary than in infrainguinal vein grafts. As constrictive external mesh support of vein grafts led to the complete suppression of intimal hyperplasia (IH) in infrainguinal grafts, we investigated whether mesh constriction is equally effective in the coronary position. METHODS Eighteen senescent Chacma baboons (28.8 ± 3.6 kg) received aorto-coronary bypass grafts to the left anterior descending artery (LAD). Three groups of saphenous vein grafts were compared: untreated controls (CO); fibrin sealant-sprayed controls (CO + FS) and nitinol mesh-constricted grafts (ME + FS). Meshes consisted of pulse-compliant, knitted nitinol (eight needles; 50 μm wire thickness; 3.4 mm resting inner diameter, ID) spray attached to the vein grafts with FS. After 180 days of implantation, luminal dimensions and IH were analysed using post-explant angiography and macroscopic and histological image analysis. RESULTS At implantation, the calibre mismatch between control grafts and the LAD expressed as cross-sectional quotient (Qc) was pronounced [Qc = 0.21 ± 0.07 (CO) and 0.18 ± 0.05 (CO + FS)]. Mesh constriction resulted in a 29 ± 7% reduction of the outer diameter of the vein grafts from 5.23 ± 0.51 to 3.68 ± 0 mm, significantly reducing the calibre discrepancy to a Qc of 0.41 ± 0.17 (P < 0.02). After 6 months of implantation, explant angiography showed distinct luminal irregularities in control grafts (ID difference between widest and narrowest segment 74 ± 45%), while diameter variations were mild in mesh-constricted grafts. In all control grafts, thick neointimal tissue was present [600 ± 63 μm (CO); 627 ± 204 μm (CO + FS)] as opposed to thin, eccentric layers of 249 ± 83 μm in mesh-constricted grafts (ME + FS; P < 0.002). The total wall thickness had increased by 363 ± 39% (P < 0.00001) in CO and 312 ± 61% (P < 0.00001) in CO + FS vs 82 ± 61% in ME + FS (P < 0.007). CONCLUSIONS In a senescent non-human primate model for coronary artery bypass grafts, constrictive, external mesh support of saphenous veins with knitted nitinol prevented focal, irregular graft narrowing and suppressed neointimal tissue proliferation by a factor of 2.5. The lower degree of suppression of IH compared with previous infrainguinal grafts coincided with a lesser reduction of calibre mismatch in the coronary grafts. PMID:23295444

Pilot study on objective measurement of abdominal wall strength in patients with ventral incisional hernia.

PubMed

Parker, Michael; Goldberg, Ross F; Dinkins, Maryane M; Asbun, Horacio J; Daniel Smith, C; Preissler, Susanne; Bowers, Steven P

2011-11-01

Outcomes after ventral incisional hernia (VIH) repair are measured by recurrence rate and subjective measures. No objective metrics evaluate functional outcomes after abdominal wall reconstruction. This study aimed to develop testing of abdominal wall strength (AWS) that could be validated as a useful metric. Data were prospectively collected during 9 months from 35 patients. A total of 10 patients were evaluated before and after VIH repair, for a total of 45 encounters. The patients were tested simultaneously or in succession by two of three examiners. Data were collected for three tests: double leg lowering (DLL), trunk raising (TR), and supine reaching (SR). Raw data were compared and tested for validity, and continuous data were transformed to categorical data. Agreement was measured using the intraclass correlation coefficient (ICC) for DLL and using kappa for the ordinal measures. Simultaneous testing yielded the following interobserver reliability: DLL (0.96 and 0.87), TR (1.00 and 0.95), and SR (0.76). Reproducibility was assessed by consecutive tests, with correlation as follows: DLL (0.81), TR (0.81), and RCH (0.21). Due to poor interobserver reliability for the SR test compared with the DLL and TR tests, the SR test was excluded from calculation of an overall score. Based on raw data distribution from the DLL and TR tests, the DLL data were categorized into 10º increments, allowing construction of a 10-point score. The median AWS score was 5 (interquartile range [IQR], 4-7), and there was agreement within 1 point for 42 of the 45 encounters (93%). The findings from this study demonstrate that the 10-point AWS score may measure AWS in an accurate and reproducible fashion, with potential for objective description of abdominal wall function of VIH patients. This score may help to identify patients suited for abdominal wall reconstruction while measuring progress after VIH repair. Further longitudinal outcomes studies are needed.

Emotional expression and heart rate in high-risk infants during the face-to-face/still-face.

PubMed

Mattson, Whitney I; Ekas, Naomi V; Lambert, Brittany; Tronick, Ed; Lester, Barry M; Messinger, Daniel S

2013-12-01

In infants, eye constriction-the Duchenne marker-and mouth opening appear to index the intensity of both positive and negative facial expressions. We combined eye constriction and mouth opening that co-occurred with smiles and cry-faces (respectively, the prototypic expressions of infant joy and distress) to measure emotional expression intensity. Expression intensity and heart rate were measured throughout the face-to-face/still-face (FFSF) in a sample of infants with prenatal cocaine exposure who were at risk for developmental difficulties. Smiles declined and cry-faces increased in the still-face episode, but the distribution of eye constriction and mouth opening in smiles and cry-faces did not differ across episodes of the FFSF. As time elapsed in the still face episode potential indices of intensity increased, cry-faces were more likely to be accompanied by eye constriction and mouth opening. During cry-faces there were also moderately stable individual differences in the quantity of eye constriction and mouth opening. Infant heart rate was higher during cry-faces and lower during smiles, but did not vary with intensity of expression or by episode. In sum, infants express more intense negative affect as the still-face progresses, but do not show clear differences in expressive intensity between episodes of the FFSF. Copyright © 2013 Elsevier Inc. All rights reserved.

Emergency department assessment of abdominal pain: clinical indicator tests for detecting peritonism.

PubMed

Taylor, Scott; Watt, Martin

2005-12-01

Peritonism is a finding that leads to a more cautious approach in the emergency department management of abdominal pain. This study examined whether peritonism assessment using inspiration, expiration and cough tests was associated with the patient's clinical management. This prospective observational study evaluated consecutive patients presenting directly to the emergency department for 3 months from June 2000 with abdominal pain. Triage initial observations of blood pressure, pulse, respiratory rate, oxygen saturation and temperature were recorded. The examining emergency physician recorded each patient's response and pain score to the individual peritonism tests and scored it as positive if there was an indication of it being a painful manoeuvre. The results were blinded from the receiving specialty if subsequent referral was required. Sixty-seven patients had peritonism tests performed. No individual test was more painful than the others with similar values in pain scores. In all, 70% (7/10) were admitted when all three tests were positive, compared with 21% (12/57) when two or less of the tests scored positive (P=0.004, Fisher's exact test). Admission was not associated with any individual test or combination of tests, or any other variable. The peritonism tests were not associated with any other physiological observation or measurement. These peritonism tests represent a simple investigation, and are significantly associated with admission when all three tests are positive. They seem to be a clinical predictor of cases in which continuing assessment was required, and may be useful as a departmental 'safety net' in the management of abdominal pain.

Juvenile granulosa cell tumor arising from intra-abdominal testis in newborn: case report and review of the literature.

PubMed

Partalis, Nikolaos; Tzardi, Maria; Barbagadakis, Sophia; Sakellaris, George

2012-05-01

In the present case, the neonate presented with a left-sided abdominal mass and an empty left scrotum. Abdominal ultrasonography showed well-defined cystic formation, and laparotomy revealed a tumor arising from an intra-abdominal left testis. The carcinoembryonic antigen and neuron-specific enolase levels were within normal limits, and the serum β-human chorionic gonadotropin and α-fetoprotein levels were within age-related normal values. The findings from the immunochemistry tests confirmed the diagnosis. Copyright © 2012 Elsevier Inc. All rights reserved.

Common Functional Gastroenterologic Disorders Associated With Abdominal Pain

PubMed Central

Bharucha, Adil E.; Chakraborty, Subhankar; Sletten, Christopher D.

2016-01-01

Although abdominal pain is a symptom of several structural gastrointestinal disorders (eg, peptic ulcer disease), this comprehensive review will focus on the 4 most common nonstructural, or functional, disorders associated with abdominal pain: functional dyspepsia, constipation-predominant and diarrhea-predominant irritable bowel syndrome, and functional abdominal pain syndrome. Together, these conditions affect approximately 1 in 4 people in the United States. They are associated with comorbid conditions (eg, fibromyalgia, depression), impaired quality of life, and increased health care utilization. Symptoms are explained by disordered gastrointestinal motility and sensation, which are implicated in a variety of peripheral (eg, postinfectious inflammation, luminal irritants) and/or central (eg, stress and anxiety) factors. These disorders are defined and can generally be diagnosed by symptoms alone. Often prompted by alarm features, selected testing is useful to exclude structural disease. Identifying the specific diagnosis (eg, differentiating between functional abdominal pain and irritable bowel syndrome) and establishing an effective patient-physician relationship are the cornerstones of therapy. Many patients with mild symptoms can be effectively managed with limited tests, sensible dietary modifications, and over-the-counter medications tailored to symptoms. If these measures are not sufficient, pharmacotherapy should be considered for bowel symptoms (constipation or diarrhea) and/or abdominal pain; opioids should not be used. Behavioral and psychological approaches (eg, cognitive behavioral therapy) can be very helpful, particularly in patients with chronic abdominal pain who require a multidisciplinary pain management program without opioids. PMID:27492916

Abnormal Transient Pupillary Light Reflex in Individuals with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Fan, Xiaofei; Miles, Judith H.; Takahashi, Nicole; Yao, Gang

2009-01-01

Computerized binocular infrared pupillography was used to measure the transient pupillary light reflex (PLR) in both children with autism spectrum disorders (ASDs) and children with typical development. We found that participants with ASDs showed significantly longer PLR latency, smaller constriction amplitude and lower constriction velocity than…

Dataset of red light induced pupil constriction superimposed on post-illumination pupil response.

PubMed

Lei, Shaobo; Goltz, Herbert C; Sklar, Jaime C; Wong, Agnes M F

2016-09-01

We collected and analyzed pupil diameter data from of 7 visually normal participants to compare the maximum pupil constriction (MPC) induced by "Red Only" vs. "Blue+Red" visual stimulation conditions. The "Red Only" condition consisted of red light (640±10 nm) stimuli of variable intensity and duration presented to dark-adapted eyes with pupils at resting state. This condition stimulates the cone-driven activity of the intrinsically photosensitive retinal ganglion cells (ipRGC). The "Blue+Red" condition consisted of the same red light stimulus presented during ongoing blue (470±17 nm) light-induced post-illumination pupil response (PIPR), representing the cone-driven ipRGC activity superimposed on the melanopsin-driven intrinsic activity of the ipRGCs ("The Absence of Attenuating Effect of Red light Exposure on Pre-existing Melanopsin-Driven Post-illumination Pupil Response" Lei et al. (2016) [1]). MPC induced by the "Red Only" condition was compared with the MPC induced by the "Blue+Red" condition by multiple paired sample t -tests with Bonferroni correction.

A Comparison of the US Air Force Fitness Test and Sister Services’ Combat-Oriented Fitness Tests

DTIC Science & Technology

2009-03-01

could lead to injuries such as twisted ankles, sprains, bruises, lower back pain, abdominal cramps and pain, muscle fatigue , strains, exhaustion, nausea...twisted ankles, sprains, bruises, lower back pain, abdominal cramps and pain, muscle fatigue , strains, exhaustion, nausea, headaches, or other...combat skills, anaerobic exercises, and burst speed exercises. They have, or are in the process of, creating their own versions of combat fitness tests

Relationship Between Abdominal Symptoms and Fructose Ingestion in Children with Chronic Abdominal Pain.

PubMed

Hammer, Veronika; Hammer, Katharina; Memaran, Nima; Huber, Wolf-Dietrich; Hammer, Karin; Hammer, Johann

2018-05-01

Limited valid data are available regarding the association of fructose-induced symptoms, fructose malabsorption, and clinical symptoms. To develop a questionnaire for valid symptom assessment before and during a carbohydrate breath test and to correlate symptoms with fructose breath test results in children/adolescents with functional abdominal pain. A Likert-type questionnaire assessing symptoms considered relevant for hydrogen breath test in children was developed and underwent initial validation. Fructose malabsorption was determined by increased breath hydrogen in 82 pediatric patients with functional abdominal pain disorders; fructose-induced symptoms were quantified by symptom score ≥2 and relevant symptom increase over baseline. The results were correlated with clinical symptoms. The time course of symptoms during the breath test was assessed. The questionnaire exhibited good psychometric properties in a standardized assessment of the severity of carbohydrate-related symptoms. A total of 40 % (n = 33) had malabsorption; symptoms were induced in 38 % (n = 31), but only 46 % (n = 15) with malabsorption were symptomatic. There was no significant correlation between fructose malabsorption and fructose-induced symptoms. Clinical symptoms correlated with symptoms evoked during the breath test (p < 0.001, r 2  = 0.21) but not with malabsorption (NS). Malabsorbers did not differ from non-malabsorbers in terms of symptoms during breath test. Symptomatic patients had significantly higher pain and flatulence scores over the 9-h observation period (p < 0.01) than did nonsymptomatic patients; the meteorism score was higher after 90 min. Fructose-induced symptoms but not fructose malabsorption are related to increased abdominal symptoms and have distinct timing patterns.

Transfer Learning with Convolutional Neural Networks for Classification of Abdominal Ultrasound Images.

PubMed

Cheng, Phillip M; Malhi, Harshawn S

2017-04-01

The purpose of this study is to evaluate transfer learning with deep convolutional neural networks for the classification of abdominal ultrasound images. Grayscale images from 185 consecutive clinical abdominal ultrasound studies were categorized into 11 categories based on the text annotation specified by the technologist for the image. Cropped images were rescaled to 256 × 256 resolution and randomized, with 4094 images from 136 studies constituting the training set, and 1423 images from 49 studies constituting the test set. The fully connected layers of two convolutional neural networks based on CaffeNet and VGGNet, previously trained on the 2012 Large Scale Visual Recognition Challenge data set, were retrained on the training set. Weights in the convolutional layers of each network were frozen to serve as fixed feature extractors. Accuracy on the test set was evaluated for each network. A radiologist experienced in abdominal ultrasound also independently classified the images in the test set into the same 11 categories. The CaffeNet network classified 77.3% of the test set images accurately (1100/1423 images), with a top-2 accuracy of 90.4% (1287/1423 images). The larger VGGNet network classified 77.9% of the test set accurately (1109/1423 images), with a top-2 accuracy of VGGNet was 89.7% (1276/1423 images). The radiologist classified 71.7% of the test set images correctly (1020/1423 images). The differences in classification accuracies between both neural networks and the radiologist were statistically significant (p < 0.001). The results demonstrate that transfer learning with convolutional neural networks may be used to construct effective classifiers for abdominal ultrasound images.

Consumption of a liquid high-fat meal increases triglycerides but decreases high-density lipoprotein cholesterol in abdominally obese subjects with high postprandial insulin resistance.

PubMed

Wang, Feng; Lu, Huixia; Liu, Fukang; Cai, Huizhen; Xia, Hui; Guo, Fei; Xie, Yulan; Huang, Guiling; Miao, Miao; Shu, Guofang; Sun, Guiju

2017-07-01

Abdominal obesity is associated with an increased risk of insulin resistance, which may be a potential contributor to dyslipidemia. However, the relationship between postprandial insulin resistance and lipid metabolism in abdominally obese subjects remains unknown. We hypothesized that postprandial dyslipidemia would be exaggerated in abdominally obese subjects with high postprandial insulin resistance. To test this hypothesis, serum glucose, insulin, triglycerides, total cholesterol, high-density lipoprotein cholesterol, and apolipoprotein B were measured at baseline and postprandial state at 0.5, 1, 2, 4, 6, and 8 hours after a liquid high-fat meal in non-abdominally obese controls (n=44) and abdominally obese subjects with low (AO-LPIR, n=40), middle (n=40), and high postprandial insulin resistance (AO-HPIR, n=40) based on the tertiles ratio of the insulin to glucose areas under the curve (AUC). Their serum adipokines were tested at baseline only. Fasting serum leptin was higher (P<.05) in AO-HPIR than that in AO-LPIR and controls. Postprandial triglycerides AUC was higher (P<.05), whereas high-density lipoprotein cholesterol AUC was lower (P<.05), in AO-HPIR than those in AO-LPIR and controls. Postprandial AUCs for total cholesterol and apolipoprotein B were similar in abdominally obese subjects with different degrees of postprandial insulin resistance and controls. The present study indicated that the higher degree of postprandial insulin resistance, the more adverse lipid profiles in abdominally obese subjects, which provides insight into opportunity for screening in health. Copyright © 2017 Elsevier Inc. All rights reserved.

Postrenal acute kidney injury in a patient with unilateral ureteral obstruction caused by urolithiasis: A case report.

PubMed

Kazama, Itsuro; Nakajima, Toshiyuki

2017-10-01

In patients with bilateral ureteral obstruction, the serum creatinine levels are often elevated, sometimes causing postrenal acute kidney injury (AKI). In contrast, those with unilateral ureteral obstruction present normal serum creatinine levels, as long as their contralateral kidneys are preserved intact. However, the unilateral obstruction of the ureter could affect the renal function, as it humorally influences the renal hemodynamics. A 66-year-old man with a past medical history of hypertension and diabetes mellitus came to our outpatient clinic because of right abdominal dullness. Unilateral ureteral obstruction caused by a radio-opaque calculus in the right upper ureter and a secondary renal dysfunction. As oral hydration and the use of calcium antagonists failed to allow the spontaneous stone passage, extracorporeal shock wave lithotripsy (ESWL) was performed. Immediately after the passage of the stone, the number of red blood cells in the urine was dramatically decreased and the serum creatinine level almost returned to the normal range with the significant increase in glomerular filtration rate. Unilateral ureteral obstruction by the calculus, which caused reflex vascular constriction and ureteral spasm in the contralateral kidney, was thought to be responsible for the deteriorating renal function.

Effects of Various Types of Situps on Integrated MAP's of the Abdominal Musculature.

ERIC Educational Resources Information Center

Noble, Larry

The electrical activity of the abdominal muscles was tested during situps to determine the effect upon integrated muscle action potential (MAP). The following types of situps were used in testing 18 college males: (1) trunk curls; (2) AAHPER situp; (3) YMCA situp; (4) modified AAHPER situp; and (5) modified YMCA situp. All situps were performed…

Does this adult patient have a blunt intra-abdominal injury?

PubMed

Nishijima, Daniel K; Simel, David L; Wisner, David H; Holmes, James F

2012-04-11

Blunt abdominal trauma often presents a substantial diagnostic challenge. Well-informed clinical examination can identify patients who require further diagnostic evaluation for intra-abdominal injuries after blunt abdominal trauma. To systematically assess the precision and accuracy of symptoms, signs, laboratory tests, and bedside imaging studies to identify intra-abdominal injuries in patients with blunt abdominal trauma. We conducted a structured search of MEDLINE (1950-January 2012) and EMBASE (1980-January 2012) to identify English-language studies examining the identification of intra-abdominal injuries. A separate, structured search was conducted for studies evaluating bedside ultrasonography. We included studies of diagnostic accuracy for intra-abdominal injury that compared at least 1 finding with a reference standard of abdominal computed tomography, diagnostic peritoneal lavage, laparotomy, autopsy, and/or clinical course for intra-abdominal injury. Twelve studies on clinical findings and 22 studies on bedside ultrasonography met inclusion criteria for data extraction. Critical appraisal and data extraction were independently performed by 2 authors. The prevalence of intra-abdominal injury in adult emergency department patients with blunt abdominal trauma among all evidence level 1 and 2 studies was 13% (95% CI, 10%-17%), with 4.7% (95% CI, 2.5%-8.6%) requiring therapeutic surgery or angiographic embolization of injuries. The presence of a seat belt sign (likelihood ratio [LR] range, 5.6-9.9), rebound tenderness (LR, 6.5; 95% CI, 1.8-24), hypotension (LR, 5.2; 95% CI, 3.5-7.5), abdominal distention (LR, 3.8; 95% CI, 1.9-7.6), or guarding (LR, 3.7; 95% CI, 2.3-5.9) suggest an intra-abdominal injury. The absence of abdominal tenderness to palpation does not rule out an intra-abdominal injury (summary LR, 0.61; 95% CI, 0.46-0.80). The presence of intraperitoneal fluid or organ injury on bedside ultrasound assessment is more accurate than any history and physical examination findings (adjusted summary LR, 30; 95% CI, 20-46); conversely, a normal ultrasound result decreases the chance of injury detection (adjusted summary LR, 0.26; 95% CI, 0.19-0.34). Test results increasing the likelihood of intra-abdominal injury include a base deficit less than -6 mEq/L (LR, 18; 95% CI, 11-30), elevated liver transaminases (LR range, 2.5-5.2), hematuria (LR range, 3.7-4.1), anemia (LR range, 2.2-3.3), and abnormal chest radiograph (LR range, 2.5-3.8). Symptoms and signs may be most useful in combination, particularly in identification of patients who do not need further diagnostic workup. Bedside ultrasonography has the highest accuracy of all individual findings, but a normal result does not rule out an intra-abdominal injury. Combinations of clinical findings may be most useful to determine which patients do not require further evaluation, but the ideal combination of variables for identifying patients without intra-abdominal injury requires further study.

Anomalous right coronary artery arising from the pulmonary artery and constrictive pericarditis: an unusual association

PubMed Central

Silvestre, Odilson Marcos; Adam, Eduardo Leal; de Melo, Dirceu Thiago Pessoa; Dias, Ricardo Ribeiro; Ramires, Felix J. A.; Mady, Charles

2013-01-01

ABSTRACT The association of anomalous right coronary artery originating from the pulmonary artery and constrictive pericarditis has never been showed in the literature. We present the first case of this unusual association in a patient with right heart failure. After diagnosis, the patient was referred to surgery and underwent phrenic-to-phrenic pericardiectomy; graft implant of right internal thoracic artery to right coronary artery; and ligation of the anomalous origin of the right coronary artery from the pulmonary artery. Such procedures solved the potential risk of sudden death related to anomalous right coronary artery originating from the pulmonary artery and alleviated the symptoms of heart failure caused by constrictive pericarditis. PMID:24136766

A rare combination of amniotic constriction band with osteogenesis imperfecta.

PubMed

Shah, Krupa Hitesh; Shah, Hitesh

2015-11-11

Amniotic constriction bands and osteogenesis imperfecta are disorders arising from a collagen defect. We report a rare association of amniotic bands with osteogenesis imperfecta in a child. The child was born with multiple amniotic bands involving the right leg, both hands and both feet. Multiple fractures of long bones of lower limbs occurred in childhood due to trivial trauma. Deformities of the femur and tibia due to malunion with osteopenia and blue sclerae were present. The patient was treated with z plasty of constriction band of the right tibia and bisphosphonate for osteogenesis imperfecta. This rare association of both collagen diseases may provide further insight for the pathogenesis of these diseases. 2015 BMJ Publishing Group Ltd.

Laparoscopic Stephen-Fowler stage procedure: appropriate management for high intra-abdominal testes.

PubMed

Agrawal, Amit; Joshi, Milind; Mishra, Pankaj; Gupta, Rahul; Sanghvi, Beejal; Parelkar, Sandesh

2010-03-01

The length of testicular vessels is the main length-limiting factor to bring down the testes in the scrotum. Fowler and Stephen proposed the division of testicular vessels, high and as far from the testes as possible to maintain collateral blood supply, to treat high intra-abdominal testes. Cortesi introduced the diagnostic laparoscopy and Jorden first did the laparoscopic orchiopexy for nonpalpable testes. We had done Fowler-Stephen staged orchiopexy for high intra-abdominal testes, in which both stages were done laparoscopically. In total, 17 testes of 13 patients had undergone laparoscopic staged Fowler-Stephen orchiopexy. The decision to perform a staged Fowler-Stephen orchiopexy was based on the distance of the testis from the deep inguinal ring on laparoscopy. If distance was more than 2.5 cm, then we proceeded to a laparoscopic staged Fowler-Stephen orchiopexy. In the first stage, testicular vessels were cauterized by bipolar diathermy. Laparoscopic second-stage Fowler-Stephen procedure was done 6 months after the first stage. Patients were regularly followed, and the success of the procedure was assessed by the size of the testes and the position in the scrotum. Testicular vascularity was assessed by color Doppler ultrasonography. There was no testicular atrophy on second stage and on follow-up. All testes were in the scrotum with good size on follow-up. There was no complication related to laparoscopy. In cases of high intra-abdominal testes, the staged Fowler-Stephen procedure should be the procedure of choice. This procedure yields a high success rate. Transaction of vessels by bipolar diathermy is a very safe, cost-effective method.

Death Anxiety and Disengagement.

ERIC Educational Resources Information Center

Fried-Cassorla, Martha

This study hypothisized that when a person perceives his social network as constricted, and this constriction has been a "conscious" decision by that individual, then he or she should express little death anxiety. Subjects were 38 individuals who were at least age 60. Of these, 18 were members of the Gray Panthers (with expanding numbers of social…

Contraction of the Ventral Abdomen Potentiates Extracardiac Retrograde Hemolymph Propulsion in the Mosquito Hemocoel

PubMed Central

Andereck, Jonathan W.; King, Jonas G.; Hillyer, Julián F.

2010-01-01

Background Hemolymph circulation in mosquitoes is primarily controlled by the contractile action of a dorsal vessel that runs underneath the dorsal midline and is subdivided into a thoracic aorta and an abdominal heart. Wave-like peristaltic contractions of the heart alternate in propelling hemolymph in anterograde and retrograde directions, where it empties into the hemocoel at the terminal ends of the insect. During our analyses of hemolymph propulsion in Anopheles gambiae, we observed periodic ventral abdominal contractions and hypothesized that they promote extracardiac hemolymph circulation in the abdominal hemocoel. Methodology/Principal Findings We devised methods to simultaneously analyze both heart and abdominal contractions, as well as to measure hemolymph flow in the abdominal hemocoel. Qualitative and quantitative analyses revealed that ventral abdominal contractions occur as series of bursts that propagate in the retrograde direction. Periods of ventral abdominal contraction begin only during periods of anterograde heart contraction and end immediately following a heartbeat directional reversal, suggesting that ventral abdominal contractions function to propel extracardiac hemolymph in the retrograde direction. To test this functional role, fluorescent microspheres were intrathoracically injected and their trajectory tracked throughout the hemocoel. Quantitative measurements of microsphere movement in extracardiac regions of the abdominal cavity showed that during periods of abdominal contractions hemolymph flows in dorsal and retrograde directions at a higher velocity and with greater acceleration than during periods of abdominal rest. Histochemical staining of the abdominal musculature then revealed that ventral abdominal contractions result from the contraction of intrasegmental lateral muscle fibers, intersegmental ventral muscle bands, and the ventral transverse muscles that form the ventral diaphragm. Conclusions/Significance These data show that abdominal contractions potentiate extracardiac retrograde hemolymph propulsion in the abdominal hemocoel during periods of anterograde heart flow. PMID:20886066

Constriction structures related to viscous collision, southern Prince Charles Mountains, Antarctica

NASA Astrophysics Data System (ADS)

Corvino, Adrian F.; Boger, Steven D.; Fay, Clement

2016-09-01

Macroscopic structures are investigated in a zone of highly contorted migmatites from the southern Prince Charles Mountains, Antarctica. Here, L-tectonite fabrics, rods, mullions, boudin pods, elongate enclaves, and fold hinges, are persistent linear features all plunging gently to the northeast. In contrast, amoeboid folds, ptygmatic folds and folded boudins with different orientations are the characteristic structures in transverse sections (perpendicular to the lineation). No consistent shear sense is recognised in any dimension. Together with strain and shape analysis, these observations strongly suggest that the deformation pattern is one of folding and stretching by constriction. Previous timing constraints indicate that this deformation overlapped with the waning stages of anatexis during decompression at approximately 510 Ma, up to 30 million years after initial orogeny at 540 Ma. The zone affected by constriction is several kilometres wide and has a contorted flower-like shape confined between two broad domal antiforms. In this context, the constricted zone is interpreted as a relatively late tectonic feature that could have formed via deep-seated viscous collision in response to orogenic collapse and doming.

A case report of umbilical ring constriction with application of amnioinfusion.

PubMed

Tokunaka, Mayumi; Hasegawa, Junichi; Nakamura, Masamitsu; Hamada, Shoko; Matsuoka, Ryu; Ichizuka, Kiyotake; Sekizawa, Akihiko; Okai, Takashi

2013-07-01

This is a case report of a pregnant 38-year-old primigravida woman. Due to severe fetal growth restriction and oligohydramnios, she was referred to our tertiary perinatal center at 24 weeks' gestation. To rule out chromosomal abnormalities and facilitate ultrasound evaluation of fetal morphology, we performed amniocentesis and subsequent amnioinfusion. Thereafter, a precise ultrasound examination revealed no obvious fetal morphological abnormalities except for a hyper-coiled cord and marginal placenta previa. During expectant management, the amount of amniotic fluid was maintained at 20-26 mm for a few days; however, the pregnancy resulted in intrauterine fetal death after 26 weeks + 5 days of gestation. The stillborn infant weighed 530 g (-3.3 SD) and had no obvious external abnormalities apart from umbilical ring constriction. Although a postmortem autopsy was not performed, it is suspected that the fetal growth restriction and the intrauterine fetal death were associated with the hyper-coiled cord and the umbilical ring constriction. It is thought that umbilical ring constriction might therefore be an irreversible fatal condition in cases with a hyper-coiled cord.

Apical constriction is driven by a pulsatile apical myosin network in delaminating Drosophila neuroblasts.

PubMed

An, Yanru; Xue, Guosheng; Shaobo, Yang; Mingxi, Deng; Zhou, Xiaowei; Yu, Weichuan; Ishibashi, Toyotaka; Zhang, Lei; Yan, Yan

2017-06-15

Cell delamination is a conserved morphogenetic process important for the generation of cell diversity and maintenance of tissue homeostasis. Here, we used Drosophila embryonic neuroblasts as a model to study the apical constriction process during cell delamination. We observe dynamic myosin signals both around the cell adherens junctions and underneath the cell apical surface in the neuroectoderm. On the cell apical cortex, the nonjunctional myosin forms flows and pulses, which are termed medial myosin pulses. Quantitative differences in medial myosin pulse intensity and frequency are crucial to distinguish delaminating neuroblasts from their neighbors. Inhibition of medial myosin pulses blocks delamination. The fate of a neuroblast is set apart from that of its neighbors by Notch signaling-mediated lateral inhibition. When we inhibit Notch signaling activity in the embryo, we observe that small clusters of cells undergo apical constriction and display an abnormal apical myosin pattern. Together, these results demonstrate that a contractile actomyosin network across the apical cell surface is organized to drive apical constriction in delaminating neuroblasts. © 2017. Published by The Company of Biologists Ltd.

A mitochondria-anchored isoform of the actin-nucleating spire protein regulates mitochondrial division.

PubMed

Manor, Uri; Bartholomew, Sadie; Golani, Gonen; Christenson, Eric; Kozlov, Michael; Higgs, Henry; Spudich, James; Lippincott-Schwartz, Jennifer

2015-08-25

Mitochondrial division, essential for survival in mammals, is enhanced by an inter-organellar process involving ER tubules encircling and constricting mitochondria. The force for constriction is thought to involve actin polymerization by the ER-anchored isoform of the formin protein inverted formin 2 (INF2). Unknown is the mechanism triggering INF2-mediated actin polymerization at ER-mitochondria intersections. We show that a novel isoform of the formin-binding, actin-nucleating protein Spire, Spire1C, localizes to mitochondria and directly links mitochondria to the actin cytoskeleton and the ER. Spire1C binds INF2 and promotes actin assembly on mitochondrial surfaces. Disrupting either Spire1C actin- or formin-binding activities reduces mitochondrial constriction and division. We propose Spire1C cooperates with INF2 to regulate actin assembly at ER-mitochondrial contacts. Simulations support this model's feasibility and demonstrate polymerizing actin filaments can induce mitochondrial constriction. Thus, Spire1C is optimally positioned to serve as a molecular hub that links mitochondria to actin and the ER for regulation of mitochondrial division.

Tumbling cartilage flap and free auricular composite tissue transplantation for correcting mild and moderate forms of constricted ear.

PubMed

Pan, Bo; Zhao, Yanyong; Zhuang, Hongxing; Lin, Lin; Liu, Lei; Jiang, Haiyue

2010-01-01

To report a new surgical approach that results in a natural size and contour of the external malformed constricted ear. A total of 62 consecutive patients with constricted ear underwent surgery between July 1, 2005, and December 31, 2007. Depending on the features and severity of the deformity, the methods of tumbling cartilage flap (CF), free auricular composite graft, or a combination of these 2 techniques were applied. A total of 45 patients were treated with the method of tumbling CF. Twelve were treated with an auricular composite graft from the contralateral ear, and in 5 patients a combination of the 2 methods was used. In all cases, there was an improvement in the size, shape, and symmetry of the ears, and most patients were satisfied with the outcome. Complications were rare, and there was no donor site deformity. The technique of tumbling CF and free auricular composite graft provides a simple and promising treatment for constricted ears. Furthermore, this technique is easy to apply with a predictable good outcome.

Changes in compressed neurons from dogs with acute and severe cauda equina constrictions following intrathecal injection of brain-derived neurotrophic factor-conjugated polymer nanoparticles☆

PubMed Central

Tan, Junming; Shi, Jiangang; Shi, Guodong; Liu, Yanling; Liu, Xiaohong; Wang, Chaoyang; Chen, Dechun; Xing, Shunming; Shen, Lianbing; Jia, Lianshun; Ye, Xiaojian; He, Hailong; Li, Jiashun

2013-01-01

This study established a dog model of acute multiple cauda equina constriction by experimental constriction injury (48 hours) of the lumbosacral central processes in dorsal root ganglia neurons. The repair effect of intrathecal injection of brain-derived neurotrophic factor with 15 mg encapsulated biodegradable poly(lactide-co-glycolide) nanoparticles on this injury was then analyzed. Dorsal root ganglion cells (L7) of all experimental dogs were analyzed using hematoxylin-eosin staining and immunohistochemistry at 1, 2 and 4 weeks following model induction. Intrathecal injection of brain-derived neurotrophic factor can relieve degeneration and inflammation, and elevate the expression of brain-derived neurotrophic factor in sensory neurons of compressed dorsal root ganglion. Simultaneously, intrathecal injection of brain-derived neurotrophic factor obviously improved neurological function in the dog model of acute multiple cauda equina constriction. Results verified that sustained intraspinal delivery of brain-derived neurotrophic factor encapsulated in biodegradable nanoparticles promoted the repair of histomorphology and function of neurons within the dorsal root ganglia in dogs with acute and severe cauda equina syndrome. PMID:25206593

Pupil-mimicry conditions trust in partners: moderation by oxytocin and group membership

PubMed Central

De Dreu, Carsten K. W.

2017-01-01

Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to others, by contracting the muscles around their eyes and pupils. In our earlier research, we observed that interaction partners with dilating pupils are trusted more than partners with constricting pupils. But over and beyond this effect, we found that the pupil sizes of partners synchronize and that when pupils synchronously dilate, trust is further boosted. Critically, this linkage between mimicry and trust was bound to interactions between ingroup members. The current study investigates whether these findings are modulated by oxytocin and sex of participant and partner. Using incentivized trust games with partners from ingroup and outgroup whose pupils dilated, remained static or constricted, this study replicates our earlier findings. It further reveals that (i) male participants withhold trust from partners with constricting pupils and extend trust to partners with dilating pupils, especially when given oxytocin rather than placebo; (ii) female participants trust partners with dilating pupils most, but this effect is blunted under oxytocin; (iii) under oxytocin rather than placebo, pupil dilation mimicry is weaker and pupil constriction mimicry stronger; and (iv) the link between pupil constriction mimicry and distrust observed under placebo disappears under oxytocin. We suggest that pupil-contingent trust is parochial and evolved in social species in and because of group life. PMID:28250181

Superoxide constricts rat pulmonary arteries via Rho-kinase-mediated Ca2+ sensitization

PubMed Central

Shaifta, Yasin; Connolly, Michelle; Drndarski, Svetlana; Noah, Anthony; Pourmahram, Ghazaleh E.; Becker, Silke; Aaronson, Philip I.; Ward, Jeremy P.T.

2018-01-01

Reactive oxygen species play a key role in vascular disease, pulmonary hypertension, and hypoxic pulmonary vasoconstriction. We investigated contractile responses, intracellular Ca2+ ([Ca2+]i), Rho-kinase translocation, and phosphorylation of the regulatory subunit of myosin phosphatase (MYPT-1) and of myosin light chain (MLC20) in response to LY83583, a generator of superoxide anion, in small intrapulmonary arteries (IPA) of rat. LY83583 caused concentration-dependent constrictions in IPA and greatly enhanced submaximal PGF2α-mediated preconstriction. In small femoral or mesenteric arteries of rat, LY83583 alone was without effect, but it relaxed a PGF2α-mediated preconstriction. Constrictions in IPA were inhibited by superoxide dismutase and tempol, but not catalase, and were endothelium and guanylate cyclase independent. Constrictions were also inhibited by the Rho-kinase inhibitor Y27632 and the Src-family kinase inhibitor SU6656. LY83583 did not raise [Ca2+]i, but caused a Y27632-sensitive constriction in α-toxin-permeabilized IPA. LY83583 triggered translocation of Rho-kinase from the nucleus to the cytosol in pulmonary artery smooth muscle cells and enhanced phosphorylation of MYPT-1 at Thr-855 and of MLC20 at Ser-19 in IPA. This enhancement was inhibited by superoxide dismutase and abolished by Y27632. Hydrogen peroxide did not activate Rho-kinase. We conclude that in rat small pulmonary artery, superoxide triggers Rho-kinase-mediated Ca2+ sensitization and vasoconstriction independent of hydrogen peroxide. PMID:19103285

Redox Signaling via Oxidative Inactivation of PTEN Modulates Pressure-Dependent Myogenic Tone in Rat Middle Cerebral Arteries

PubMed Central

Gebremedhin, Debebe; Terashvili, Maia; Wickramasekera, Nadi; Zhang, David X.; Rau, Nicole; Miura, Hiroto; Harder, David R.

2013-01-01

The present study examined the level of generation of reactive oxygen species (ROS) and roles of inactivation of the phosphatase PTEN and the PI3K/Akt signaling pathway in response to an increase in intramural pressure-induced myogenic cerebral arterial constriction. Step increases in intraluminal pressure of cannulated cerebral arteries induced myogenic constriction and concomitant formation of superoxide (O2 .−) and its dismutation product hydrogen peroxide (H2O2) as determined by fluorescent HPLC analysis, microscopic analysis of intensity of dihydroethidium fluorescence and attenuation of pressure-induced myogenic constriction by pretreatment with the ROS scavenger 4,hydroxyl-2,2,6,6-tetramethylpiperidine1-oxyl (tempol) or Mito-tempol or MitoQ in the presence or absence of PEG-catalase. An increase in intraluminal pressure induced oxidation of PTEN and activation of Akt. Pharmacological inhibition of endogenous PTEN activity potentiated pressure-dependent myogenic constriction and caused a reduction in NPo of a 238 pS arterial KCa channel current and an increase in [Ca2+]i level in freshly isolated cerebral arterial muscle cells (CAMCs), responses that were attenuated by Inhibition of the PI3K/Akt pathway. These findings demonstrate an increase in intraluminal pressure induced increase in ROS production triggered redox-sensitive signaling mechanism emanating from the cross-talk between oxidative inactivation of PTEN and activation of the PI3K/Akt signaling pathway that involves in the regulation of pressure-dependent myogenic cerebral arterial constriction. PMID:23861911

Redox signaling via oxidative inactivation of PTEN modulates pressure-dependent myogenic tone in rat middle cerebral arteries.

PubMed

Gebremedhin, Debebe; Terashvili, Maia; Wickramasekera, Nadi; Zhang, David X; Rau, Nicole; Miura, Hiroto; Harder, David R

2013-01-01

The present study examined the level of generation of reactive oxygen species (ROS) and roles of inactivation of the phosphatase PTEN and the PI3K/Akt signaling pathway in response to an increase in intramural pressure-induced myogenic cerebral arterial constriction. Step increases in intraluminal pressure of cannulated cerebral arteries induced myogenic constriction and concomitant formation of superoxide (O2 (.-)) and its dismutation product hydrogen peroxide (H2O2) as determined by fluorescent HPLC analysis, microscopic analysis of intensity of dihydroethidium fluorescence and attenuation of pressure-induced myogenic constriction by pretreatment with the ROS scavenger 4,hydroxyl-2,2,6,6-tetramethylpiperidine1-oxyl (tempol) or Mito-tempol or MitoQ in the presence or absence of PEG-catalase. An increase in intraluminal pressure induced oxidation of PTEN and activation of Akt. Pharmacological inhibition of endogenous PTEN activity potentiated pressure-dependent myogenic constriction and caused a reduction in NPo of a 238 pS arterial KCa channel current and an increase in [Ca(2+)]i level in freshly isolated cerebral arterial muscle cells (CAMCs), responses that were attenuated by Inhibition of the PI3K/Akt pathway. These findings demonstrate an increase in intraluminal pressure induced increase in ROS production triggered redox-sensitive signaling mechanism emanating from the cross-talk between oxidative inactivation of PTEN and activation of the PI3K/Akt signaling pathway that involves in the regulation of pressure-dependent myogenic cerebral arterial constriction.

Distinct right ventricle remodeling in response to pressure overload in the rat.

PubMed

Mendes-Ferreira, P; Santos-Ribeiro, D; Adão, R; Maia-Rocha, C; Mendes-Ferreira, M; Sousa-Mendes, C; Leite-Moreira, A F; Brás-Silva, C

2016-07-01

Pulmonary arterial hypertension (PAH), the most serious chronic disorder of the pulmonary circulation, is characterized by pulmonary vasoconstriction and remodeling, resulting in increased afterload on the right ventricle (RV). In fact, RV function is the main determinant of prognosis in PAH. The most frequently used experimental models of PAH include monocrotaline- and chronic hypoxia-induced PAH, which primarily affect the pulmonary circulation. Alternatively, pulmonary artery banding (PAB) can be performed to achieve RV overload without affecting the pulmonary vasculature, allowing researchers to determine the RV-specific effects of their drugs/interventions. In this work, using two different degrees of pulmonary artery constriction, we characterize, in full detail, PAB-induced adaptive and maladaptive remodeling of the RV at 3 wk after PAB surgery. Our results show that application of a mild constriction resulted in adaptive hypertrophy of the RV, with preserved systolic and diastolic function, while application of a severe constriction resulted in maladaptive hypertrophy, with chamber dilation and systolic and diastolic dysfunction up to the isolated cardiomyocyte level. By applying two different degrees of constriction, we describe, for the first time, a reliable and short-duration PAB model in which RV adaptation can be distinguished at 3 wk after surgery. We characterize, in full detail, structural and functional changes of the RV in its response to moderate and severe constriction, allowing researchers to better study RV physiology and transition to dysfunction and failure, as well as to determine the effects of new therapies. Copyright © 2016 the American Physiological Society.

Functional abdominal pain syndrome treated with Korean medication.

PubMed

Son, Chang-Gue

2014-06-01

A 37-year-old female patient with chronic and stubborn abdominal pain had been hospitalized five times in three Western hospitals, but no effects were observed. No abnormalities were found in blood tests, gastrointestinal endoscopy, sonogram, and computed tomography of the abdomen, except mild paralytic ileus. The patient decided to rely on Korean medicine as an inpatient. She was diagnosed with functional abdominal pain syndrome, and her symptom differentiation was the " Yang deficiency of spleen and kidney ." A herbal drug, Hwangikyeji-tang , along with moxibustion and acupuncture, was given to the patient. Abdominal pain and related symptoms were reduced radically within 16 days of treatment. This report shows a therapeutic potential of Korean medicine-based treatment for functional abdominal pain syndrome.

Single cell rheometry with a microfluidic constriction: Quantitative control of friction and fluid leaks between cell and channel walls

PubMed Central

Preira, Pascal; Valignat, Marie-Pierre; Bico, José; Théodoly, Olivier

2013-01-01

We report how cell rheology measurements can be performed by monitoring the deformation of a cell in a microfluidic constriction, provided that friction and fluid leaks effects between the cell and the walls of the microchannels are correctly taken into account. Indeed, the mismatch between the rounded shapes of cells and the angular cross-section of standard microfluidic channels hampers efficient obstruction of the channel by an incoming cell. Moreover, friction forces between a cell and channels walls have never been characterized. Both effects impede a quantitative determination of forces experienced by cells in a constriction. Our study is based on a new microfluidic device composed of two successive constrictions, combined with optical interference microscopy measurements to characterize the contact zone between the cell and the walls of the channel. A cell squeezed in a first constriction obstructs most of the channel cross-section, which strongly limits leaks around cells. The rheological properties of the cell are subsequently probed during its entry in a second narrower constriction. The pressure force is determined from the pressure drop across the device, the cell velocity, and the width of the gutters formed between the cell and the corners of the channel. The additional friction force, which has never been analyzed for moving and constrained cells before, is found to involve both hydrodynamic lubrication and surface forces. This friction results in the existence of a threshold for moving the cells and leads to a non-linear behavior at low velocity. The friction force can nevertheless be assessed in the linear regime. Finally, an apparent viscosity of single cells can be estimated from a numerical prediction of the viscous dissipation induced by a small step in the channel. A preliminary application of our method yields an apparent loss modulus on the order of 100 Pa s for leukocytes THP-1 cells, in agreement with the literature data. PMID:24404016

A Study on Water Surface Profiles of Rivers with Constriction

NASA Astrophysics Data System (ADS)

Qian, Chaochao; Yamada, Tadashi

2013-04-01

Water surface profile of rivers with constrictions is precious in both classic hydraulics and river management practice. This study was conducted to clarify the essences of the water surface profiles. 3 cases of experiments and 1D numerical calculations with different discharges were made in the study and analysis solutions of the non-linear basic equation of surface profile in varied flow without considering friction were derived. The manning's number was kept in the same in each case by using crosspiece roughness. We found a new type of water surface profile of varied flow from the results of 1D numerical calculation and that of experiments and named it as Mc curve because of its mild condition with constriction segment. This kind of curves appears as a nature phenomenon ubiquitously. The process of water surface forming is dynamic and bore occurs at the upper side of constriction during increasing discharge before the surface profile formed. As a theoretical work, 3 analysis solutions were derived included 2 physical-meaning solutions in the study by using Man-Machine system. One of the derived physical-meaning solutions was confirmed that it is validity by comparing to the results of 1D numerical calculation and that of experiments. The solution represents a flow profile from under critical condition at the upper side to super critical condition at the down side of constriction segment. The other derived physical-meaning solution represents a flow profile from super critical condition at the upper side to under critical condition at the down side of constriction segment. These two kinds of flow profiles exist in the nature but no theoretical solution can express the phenomenon. We find the depth distribution only concerned with unit width discharge distribution and critical depth under a constant discharge from the derived solutions. Therefor, the profile can be gained simply and precisely by using the theoretical solutions instead of numerical calculation even in practice.

Stimulation of abdominal and upper thoracic muscles with surface electrodes for respiration and cough: Acute studies in adult canines.

PubMed

Walter, James S; Posluszny, Joseph; Dieter, Raymond; Dieter, Robert S; Sayers, Scott; Iamsakul, Kiratipath; Staunton, Christine; Thomas, Donald; Rabbat, Mark; Singh, Sanjay

2018-05-01

To optimize maximal respiratory responses with surface stimulation over abdominal and upper thorax muscles and using a 12-Channel Neuroprosthetic Platform. Following instrumentation, six anesthetized adult canines were hyperventilated sufficiently to produce respiratory apnea. Six abdominal tests optimized electrode arrangements and stimulation parameters using bipolar sets of 4.5 cm square electrodes. Tests in the upper thorax optimized electrode locations, and forelimb moment was limited to slight-to-moderate. During combined muscle stimulation tests, the upper thoracic was followed immediately by abdominal stimulation. Finally, a model of glottal closure for cough was conducted with the goal of increased peak expiratory flow. Optimized stimulation of abdominal muscles included three sets of bilateral surface electrodes located 4.5 cm dorsal to the lateral line and from the 8 th intercostal space to caudal to the 13 th rib, 80 or 100 mA current, and 50 Hz stimulation frequency. The maximal expired volume was 343 ± 23 ml (n=3). Optimized upper thorax stimulation included a single bilateral set of electrodes located over the 2 nd interspace, 60 to 80 mA, and 50 Hz. The maximal inspired volume was 304 ± 54 ml (n=4). Sequential stimulation of the two muscles increased the volume to 600 ± 152 ml (n=2), and the glottal closure maneuver increased the flow. Studies in an adult canine model identified optimal surface stimulation methods for upper thorax and abdominal muscles to induce sufficient volumes for ventilation and cough. Further study with this neuroprosthetic platform is warranted.

Epidemiology and antimicrobial susceptibility of Gram-negative aerobic bacteria causing intra-abdominal infections during 2010-2011.

PubMed

Hawser, Stephen; Hoban, Daryl J; Badal, Robert E; Bouchillon, Samuel K; Biedenbach, Douglas; Hackel, Meredith; Morrissey, Ian

2015-02-01

The study for monitoring antimicrobial resistance trends (SMART) surveillance program monitors the epidemiology and trends in antibiotic resistance of intra-abdominal pathogens to currently used therapies. The current report describes such trends during 2010-2011. A total of 25,746 Gram-negative clinical isolates from intra-abdominal infections were collected and classified as hospital-associated (HA) if the hospital length of stay (LOS) at the time of specimen collection was ≥48 hours, community-associated (CA) if LOS at the time of specimen collection was <48 hours, or unknown (no designation given by participating centre). A total of 92 different species were collected of which the most common was Escherichia coli: 39% of all isolates in North America to 55% in Africa. Klebsiella pneumoniae was the second most common pathogen: 11% of all isolates from Europe to 19% of all isolates from Asia. Isolates were from multiple intra-abdominal sources of which 32% were peritoneal fluid, 20% were intra-abdominal abscesses, and 16.5% were gall bladder infections. Isolates were further classified as HA (55% of all isolates), CA (39% of all isolates), or unknown (6% of all isolates). The most active antibiotics tested were imipenem, ertapenem, amikacin, and piperacillin-tazobactam. Resistance rates to all other antibiotics tested were high. Considering the current data set and high-level resistance of intra-abdominal pathogens to various antibiotics, further monitoring of the epidemiology of intra-abdominal infections and their susceptibility to antibiotics through SMART is warranted.

Common Functional Gastroenterological Disorders Associated With Abdominal Pain.

PubMed

Bharucha, Adil E; Chakraborty, Subhankar; Sletten, Christopher D

2016-08-01

Although abdominal pain is a symptom of several structural gastrointestinal disorders (eg, peptic ulcer disease), this comprehensive review will focus on the 4 most common nonstructural, or functional, disorders associated with abdominal pain: functional dyspepsia, constipation-predominant and diarrhea-predominant irritable bowel syndrome, and functional abdominal pain syndrome. Together, these conditions affect approximately 1 in 4 people in the United States. They are associated with comorbid conditions (eg, fibromyalgia and depression), impaired quality of life, and increased health care utilization. Symptoms are explained by disordered gastrointestinal motility and sensation, which are implicated in various peripheral (eg, postinfectious inflammation and luminal irritants) and/or central (eg, stress and anxiety) factors. These disorders are defined and can generally be diagnosed by symptoms alone. Often prompted by alarm features, selected testing is useful to exclude structural disease. Identifying the specific diagnosis (eg, differentiating between functional abdominal pain and irritable bowel syndrome) and establishing an effective patient-physician relationship are the cornerstones of therapy. Many patients with mild symptoms can be effectively managed with limited tests, sensible dietary modifications, and over-the-counter medications tailored to symptoms. If these measures are not sufficient, pharmacotherapy should be considered for bowel symptoms (constipation or diarrhea) and/or abdominal pain; opioids should not be used. Behavioral and psychological approaches (eg, cognitive behavioral therapy) can be helpful, particularly in patients with chronic abdominal pain who require a multidisciplinary pain management program without opioids. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Role of routine abdominal ultrasonography in intensified tuberculosis case finding algorithms at HIV clinics in high TB burden settings.

PubMed

Spalgais, Sonam; Agarwal, Upasna; Sarin, Rohit; Chauhan, Devesh; Yadav, Anita; Jaiswal, Anand

2017-05-18

High proportion of TB in people living with HIV (PLHIV) is undiagnosed. Due to this active TB case finding is recommended for HIV clinics in high TB burden countries. Presently sputum examination and chest radiography are frontline tests recommended for HIV infected TB presumptives. Abdominal TB which occurs frequently in PLHIV may be missed even by existing programmatic intensified case finding protocols. This study evaluated the routine use of ultrasonography (USG) for active case finding of abdominal TB in HIV clinics. Retrospective analysis of eight years' data from an HIV Clinic in a TB hospital in India. Patients underwent chest x-ray, sputum examination, USG abdomen and routine blood tests at entry to HIV care. Case forms were scrutinized for diagnosis of TB, USG findings and CD4 cell counts. Abdominal TB was classified as probable or possible TB. Probable TB was based on presence of two major USG (abdomen) findings suggestive of active TB, or one major USG finding with at least two minor USG findings or at least two symptoms, or any USG finding with microbiologically confirmed active TB at another site. Possible TB was based on the presence of one major USG finding, or the presence of two minor USG findings with at least two symptoms. Bacteriological confirmation was not obtained. Eight hundred and eighty-nine people PLHIV underwent a baseline USG abdomen. One hundred and thirteen of 340 cases already diagnosed with TB and 87 of the 91 newly diagnosed with TB at time of HIV clinic registration had abdominal TB. Non-abdominal symptoms like weight loss, fever and cough were seen in 53% and 22% cases had no symptoms at all. Enlarged abdominal lymph nodes with central caseation, ascitis, splenic microabsesses, bowel thickening and hepatosplenomegaly were the USG findings in these cases. Abdominal TB is a frequent TB site in PLHIV presenting with non-abdominal symptoms. It can be easily detected on basis of features seen on a simple abdominal ultrasound. Abdominal USG should be essential part of intensified TB case finding algorithms for HIV infected people living in high TB burden settings.

Anti-inflammatory and analgesic activity of novel oral aspirin-loaded nanoemulsion and nano multiple emulsion formulations generated using ultrasound cavitation.

PubMed

Tang, Siah Ying; Sivakumar, Manickam; Ng, Angela Min-Hwei; Shridharan, Parthasarathy

2012-07-01

The present study investigated the anti-inflammatory and analgesic activities of novel aspirin oil-in-water (O/W) nanoemulsion and water-in-oil-in-water (W/O/W) nano multiple emulsion formulations generated using ultrasound cavitation techniques. The anti-inflammatory activities of nanoemulsion and nano multiple emulsion were determined using the λ-carrageenan-induced paw edema model. The analgesic activities of both nanoformulations were determined using acetic acid-induced writhing response and hot plate assay. For comparison, the effect of pretreatment with blank nanoemulsion and reference aspirin suspension were also studied for their anti-inflammatory and antinociceptive activities. The results showed that oral administration of nanoemulsion and nano multiple emulsion containing aspirin (60 mg/kg) significantly reduced paw edema induced by λ-carrageenan injection. Both nanoformulations decreased the number of abdominal constriction in acetic acid-induced writhing model. Pretreatment with nanoformulations led to a significant increase in reaction time in hot plate assay. Nanoemulsion demonstrated an enhanced anti-inflammatory and analgesic effects compared to reference suspension while nano multiple emulsion exhibited a mild inhibitory effects in the three experimental animal model tests. The results obtained for nano multiple emulsion were relatively lower than reference. However, administration of blank nanoemulsion did not alter the nociceptive response significantly though it showed slight anti-inflammatory effect. These experimental studies suggest that nanoemulsion and nano multiple emulsion produced a pronounced anti-inflammatory and analgesic effects in rats and may be candidates as new nanocarriers for pharmacological NSAIDs in the treatment of inflammatory disorders and alleviating pains. Copyright © 2012 Elsevier B.V. All rights reserved.

Method matters: Experimental evidence for shorter avian sperm in faecal compared to abdominal massage samples.

PubMed

Girndt, Antje; Cockburn, Glenn; Sánchez-Tójar, Alfredo; Løvlie, Hanne; Schroeder, Julia

2017-01-01

Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males' faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically.

Development and Testing of a Fully Adaptable Membrane Bioreactor Fouling Model for a Sidestream Configuration System

PubMed Central

Paul, Parneet

2013-01-01

A dead-end filtration model that includes the three main fouling mechanisms mentioned in Hermia (i.e., cake build-up, complete pore blocking, and pore constriction) and that was based on a constant trans-membrane pressure (TMP) operation was extensively modified so it could be used for a sidestream configuration membrane bioreactor (MBR) situation. Modifications and add-ons to this basic model included: alteration so that it could be used for varying flux and varying TMP operations; inclusion of a backwash mode; it described pore constriction (i.e., irreversible fouling) in relation to the concentration of soluble microbial products (SMP) in the liquor; and, it could be used in a cross flow scenario by the addition of scouring terms in the model formulation. The additional terms in this modified model were checked against an already published model to see if they made sense, physically speaking. Next this modified model was calibrated and validated in Matlab© using data collected by carrying out flux stepping tests on both a pilot sidestream MBR plant, and then a pilot membrane filtration unit. The model fit proved good, especially for the pilot filtration unit data. In conclusion, this model formulation is of the right level of complexity to be used for most practical MBR situations. PMID:24958618

Assessment of ileal function by abdominal counting of the retention of a gamma emitting bile acid analogue.

PubMed Central

Thaysen, E H; Orholm, M; Arnfred, T; Carl, J; Rødbro, P

1982-01-01

In eight patients without gastrointestinal complaints and 30 patients with various gastrointestinal disorders ileal bile acid conservation was assessed by oral administration of 75Se 23-selena-25-homocholic acid (SeHCAT) followed by abdominal gamma counting (SeHCAT-test). The results of the test correlated fairly well with the clinical features and with the [1-14C]-cholylglycine breath test including faecal 14C measurements (breath test). Of the two bile acid absorption tests the new is perhaps the more sensitive and is the one most easily performed. PMID:7117906

The contribution of bends and constrictions of a superconducting film to the photon detection by a single-photon superconducting detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zotova, A. N., E-mail: zotova@imp.sci-nnov.ru

2016-05-15

The contribution of bends and constrictions by a superconducting film to the detection by a single photon superconducting detector is investigated. It has been shown that, for currents smaller than the minimal detection current of a straight film, the detection efficiency of a film with a constriction attains saturation upon an increase in the current, which coincides qualitatively with the behavior of this dependence observed in the experiment. It has also been found that the effect of bends in the film and the external magnetic field on the detection efficiency for low-energy photons is essential, while for high-energy photons nomore » such influence is observed.« less

Shear-stress sensitive lenticular vesicles for targeted drug delivery.

PubMed

Holme, Margaret N; Fedotenko, Illya A; Abegg, Daniel; Althaus, Jasmin; Babel, Lucille; Favarger, France; Reiter, Renate; Tanasescu, Radu; Zaffalon, Pierre-Léonard; Ziegler, André; Müller, Bert; Saxer, Till; Zumbuehl, Andreas

2012-08-01

Atherosclerosis results in the narrowing of arterial blood vessels and this causes significant changes in the endogenous shear stress between healthy and constricted arteries. Nanocontainers that can release drugs locally with such rheological changes can be very useful. Here, we show that vesicles made from an artificial 1,3-diaminophospholipid are stable under static conditions but release their contents at elevated shear stress. These vesicles have a lenticular morphology, which potentially leads to instabilities along their equator. Using a model cardiovascular system based on polymer tubes and an external pump to represent shear stress in healthy and constricted vessels of the heart, we show that drugs preferentially release from the vesicles in constricted vessels that have high shear stress.

Evaluation of constricted affect in chronic pain: an attempt using the Toronto Alexythymia Scale.

PubMed

Millard, R W; Kinsler, B L

1992-09-01

The Toronto Alexythymia Scale (TAS) was applied as a potential measure of constricted affect among a sample of patients with chronic, non-malignant pain (n = 195). As previously demonstrated with non-clinical samples, the scale was found to possess moderate reliability with two principal internal factors. These factors seemed to reflect social introversion and a lack of proneness to fantasy. There was a moderate, negative association between them. The domain sampled by the TAS was apparently heterogeneous, with total scores showing no relationship to reported disability or pain intensity and a low relationship to reported distress. These results suggest potential limitations of the TAS and the alexythymia construct as means for evaluating constricted affect that accompanies chronic pain.

Role of distal reabsorption and peritubular environment in glomerulotubular balance.

NASA Technical Reports Server (NTRS)

Schrier, R. W.; Humphreys, M. H.

1972-01-01

Total kidney glomerulotubular balance was examined during aortic constriction and release in saline-loaded dogs and in dogs undergoing water diuresis. Aortic constriction lowered the glomerular filtration rate by 45% in both groups, and glomerulotubular balance, as judged by changes in absolute sodium reabsorption, was also comparable. During water diuresis, a linear relationship was observed between free water clearance and urine flow during all maneuvers, suggesting that distal sodium reabsorption is related primarily to distal delivery. The results suggest that if alterations in the peritubular environment are responsible for the changes in tubular sodium reabsorption during aortic constriction in the saline- or water-loaded dog, then a change in renal plasma flow, and presumably delivery rate of oncotic force, may be the most likely mediator.

Shear-stress sensitive lenticular vesicles for targeted drug delivery

NASA Astrophysics Data System (ADS)

Holme, Margaret N.; Fedotenko, Illya A.; Abegg, Daniel; Althaus, Jasmin; Babel, Lucille; Favarger, France; Reiter, Renate; Tanasescu, Radu; Zaffalon, Pierre-Léonard; Ziegler, André; Müller, Bert; Saxer, Till; Zumbuehl, Andreas

2012-08-01

Atherosclerosis results in the narrowing of arterial blood vessels and this causes significant changes in the endogenous shear stress between healthy and constricted arteries. Nanocontainers that can release drugs locally with such rheological changes can be very useful. Here, we show that vesicles made from an artificial 1,3-diaminophospholipid are stable under static conditions but release their contents at elevated shear stress. These vesicles have a lenticular morphology, which potentially leads to instabilities along their equator. Using a model cardiovascular system based on polymer tubes and an external pump to represent shear stress in healthy and constricted vessels of the heart, we show that drugs preferentially release from the vesicles in constricted vessels that have high shear stress.

Abdominal pain and nausea in the diagnosis of streptococcal pharyngitis in boys

PubMed Central

Igarashi, Hiroshi; Nago, Naoki; Kiyokawa, Hiromichi; Fukushi, Motoharu

2017-01-01

Objectives This study was designed to assess the accuracy of gastrointestinal symptoms, including abdominal pain, nausea, and vomiting, in the diagnosis of Group A streptococcal (GAS) pharyngitis in children and to determine differences in diagnostic accuracy in boys versus girls. Methods This retrospective cross-sectional study included 5,755 consecutive patients aged <15 years with fever in the electronic database at a primary care practice. Gastrointestinal symptoms were recorded in the database according to the International Classification of Primary Care codes, and the data were extracted electronically. The reference standard was GAS pharyngitis diagnosed with a rapid test. Patients with a clinical diagnosis of probable GAS pharyngitis were excluded from the primary analysis. Results Among the 5,755 children with fever, 331 (5.8%) were coded as having GAS pharyngitis, including 218 (65.9%) diagnosed with rapid tests and 113 (34.1%) clinically diagnosed with probable GAS pharyngitis. Among patients with fever and abdominal pain, rapid-test-confirmed GAS pharyngitis was significantly more common in boys (11/120, 9.2%) than in girls (3/128, 2.3%; p=0.026). The positive likelihood ratio of abdominal pain was 1.49 (95% CI =0.88–2.51): 2.41 (95% CI =1.33–4.36) in boys and 0.63 (95% CI =0.20–1.94) in girls. The positive likelihood ratio of nausea was 2.05 (95% CI =1.06–4.00): 2.74 (95% CI =1.28–5.86) in boys and 1.09 (95% CI =0.27–4.42) in girls. The association between abdominal pain and GAS pharyngitis was stronger in boys aged <6 years than in boys aged 6–15 years. Conclusion Abdominal pain and nausea were associated with GAS pharyngitis in boys, but not in girls. Abdominal pain and nausea may help determine the suitability of rapid tests in younger boys with fever and other clinical findings consistent with GAS pharyngitis, even in the absence of sore throat. PMID:28989283

Measurement of superficial and deep abdominal muscle thickness: an ultrasonography study.

PubMed

Tahan, Nahid; Khademi-Kalantari, Khosro; Mohseni-Bandpei, Mohammad Ali; Mikaili, Saeed; Baghban, Alireza Akbarzadeh; Jaberzadeh, Shapour

2016-08-23

Real-time ultrasound imaging is a valid method in the field of rehabilitation. The ultrasound imaging allows direct visualization for real-time study of the muscles as they contract over the time. Measuring of the size of each abdominal muscle in relation to the others provides useful information about the differences in structure, as well as data on trunk muscle activation patterns. The purpose of this study was to assess the size and symmetry of the abdominal muscles at rest in healthy adults and to provide a reference range of absolute abdominal muscle size in a relatively large population. A total 156 healthy subjects with the age range of 18-44 years were randomly recruited. The thickness of internal oblique, external oblique, transverse abdominis, and rectus abdominis muscles was measured at rest on both right and left sides using ultrasound. Independent t test was used to compare the mean thickness of each abdominal muscle between males and females. Differences on side-to-side thicknesses were assessed using paired t test. The association between abdominal muscle thicknesses with gender and anthropometric variables was examined using the Pearson correlation coefficient. A normal pattern of increasing order of mean abdominal muscle thickness was found in both genders at both right and left sides: transverse abdominis < external oblique < internal oblique < rectus abdominis. There was a significant difference on the size of transverse abdominis, internal oblique, and external oblique muscles between right and left sides in both genders. Males had significantly thicker abdominal muscles than females. Age was significantly correlated with the thickness of internal oblique, external oblique, and rectus abdominis muscles. Body mass index was also positively correlated with muscle thickness of rectus abdominis and external oblique. The results provide a normal reference range for the abdominal muscles in healthy subjects and may be used as an index to find out abnormalities and also to evaluate the effectiveness of different interventions.

How useful is abdominal ultrasonography in dogs with diarrhoea?

PubMed

Mapletoft, E K; Allenspach, K; Lamb, C R

2018-01-01

To assess the utility of abdominal ultrasonography in the diagnostic work-up of dogs with diarrhoea. Retrospective cross-sectional study based on a referral population of dogs with diarrhoea. Associations between the clinical signs, use of abdominal ultrasonography, results of abdominal ultrasonography and subsequent work-up were examined. The utility of abdominal ultrasonography was scored as high, moderate, none or counterproductive based on review of medical records. Medical records of 269 dogs were reviewed, of which 149 (55%) had abdominal ultrasonography. The most frequent result was no ultrasonographic abnormalities affecting the intestine in 65 (44%) dogs. Ultrasonography results were associated with subsequent work-up as follows: (1) no detected abnormalities and dietary trial; (2) focal thickening of the intestinal wall, loss of intestinal wall layers or enlarged abdominal lymph nodes and ultrasound-guided fine-needle aspirates; (3) diffuse thickening of the intestinal wall or hyperechoic striations in the small intestinal mucosa and endoscopy; and (4) small intestinal foreign body and coeliotomy. Abdominal ultrasonography was considered to be diagnostic without further testing in only four (3%) dogs: two had a portosystemic shunt identified ultrasonographically, one had a linear foreign body and one had a perforated pyloric ulcer. Abdominal ultrasonography had moderate utility in 56 (38%) dogs and no utility in 79 (53%) dogs. Abdominal ultrasonography was considered counterproductive in 10 (7%) dogs because results were either falsely negative or falsely positive. These results should prompt clinicians to reconsider routine use of abdominal ultrasonography in dogs with diarrhoea. © 2017 British Small Animal Veterinary Association.

Reproducibility of regional DEXA examinations of abdominal fat and lean tissue.

PubMed

Tallroth, Kaj; Kettunen, Jyrki A; Kujala, Urho M

2013-01-01

The aim of this study was to develop and test the validity of a new repeatable method to delimit abdominal areas for follow-up of fat mass (FM) and lean tissue mass (LM) in DEXA examinations. 37 male volunteers underwent two DEXA examinations. Total body FM and LM measurements and corresponding abdominal measurements in a carefully defined region were calculated from the first scan. After repositioning of the subjects and a second scan, the delimited region was copied and the abdominal tissues re-calculated. The mean LM of the abdominal area was 2.804 kg (SD 0.556), and the mean FM was 1.026 kg (SD 0.537). The intra-class correlation coefficient for the repeated abdominal LM, FM, and LM/FM ratio measurements was 0.99. The mean difference (bias) for the repeated abdominal LM measurements was -13 g (95% confidence interval (CI) -193.0 to 166.8), and for the repeated abdominal FM measurements it was -35 g (95% CI -178.9 to 108.5). The results indicate that regional DEXA is a sensitive method with excellent reproducibility in the measurements of the abdominal fat and lean tissues. The method may serve as a useful tool for evaluation and follow-up of various dietary and training programmes.

Reproducibility of Regional DEXA Examinations of Abdominal Fat and Lean Tissue

PubMed Central

Tallroth, Kaj; Kettunen, Jyrki A.; Kujala, Urho M.

2013-01-01

Objective The aim of this study was to develop and test the validity of a new repeatable method to delimit abdominal areas for follow-up of fat mass (FM) and lean tissue mass (LM) in DEXA examinations. Methods 37 male volunteers underwent two DEXA examinations. Total body FM and LM measurements and corresponding abdominal measurements in a carefully defined region were calculated from the first scan. After repositioning of the subjects and a second scan, the delimited region was copied and the abdominal tissues re-calculated. Results The mean LM of the abdominal area was 2.804 kg (SD 0.556), and the mean FM was 1.026 kg (SD 0.537). The intra-class correlation coefficient for the repeated abdominal LM, FM, and LM/FM ratio measurements was 0.99. The mean difference (bias) for the repeated abdominal LM measurements was −13 g (95% confidence interval (CI) −193.0 to 166.8), and for the repeated abdominal FM measurements it was −35 g (95% CI −178.9 to 108.5). Conclusions The results indicate that regional DEXA is a sensitive method with excellent reproducibility in the measurements of the abdominal fat and lean tissues. The method may serve as a useful tool for evaluation and follow-up of various dietary and training programmes. PMID:23615566

Dual antiplatelet treatment in patients candidates for abdominal surgery.

PubMed

Illuminati, Giulio; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

2013-01-01

With the increasing diffusion of percutaneous interventions (PCI), surgeons are often faced with the problem of operating on patients under dual antiplatelet treatment. Replacing dual antiplatelet regiment with low molecular weight heparin may expose to the abrupt thrombosis of coronary stent and massive myocardial infarction. The purpose of this study was to test the hypothesis that abdominal operations can be safely performed under dual antiplatelet treatment. Eleven patients underwent 5 colectomies, 3 nefrectomies, 2 gastrectomies and 1 hysterectomy under aspirin and plavix without any significant perioperative hemorrhage. These preliminary results show that abdominal operations can be safely performed under dual antiplatelet regimen. Abdominal surgery, Dual antiplatelet treatment.

Chironomus alchichica sp. n. (Diptera: Chironomidae) from Lake Alchichica, Mexico.

PubMed

Acosta, Raúl; Prat, Narcís; Ribera, Carles; Michailova, Paraskeva; Hernández-Fonseca, María Del Carmen; Alcocer, Javier

2017-12-15

Morphological analysis of all developmental stages (except female), mitochondrial DNA sequences from cytochrome c oxidase subunit I (cox1) and cytological analysis of the polytene chromosomes were used to describe a new species of Chironomus found in the littoral and profundal zones of an endorheic, warm-monomictic lake in Mexico. Male imago is distinguished by the shape of superior volsella and by an antennal and bristle ratio lower than two. The pupa is characterized by the spur morphology of abdominal segment VIII. There is also a continuous row of hooklets on abdominal segment II. The larva is distinguished by a combination of antenna, mentum, mandible, and pecten epipharyngis characteristics, and abdominal ventral tubules. Molecular and cytological analysis supported the morphological differences found. The maximum likelihood tree obtained shows that Chironomus alchichica sp. n. clusters together with Chironomus decorus-group sp. 2 Butler et al. (1995) (bootstrap support = 92%), but genetic p-distances within C. alchichica sp. n. (0.004) were lower than the p-distances between other species of the decorus-group (C. decorus-group sp. 2, Chironomus bifurcatus Wülker et al., 2009 and Chironomus maturus Johannsen, 1908) confirming that it is a different species. The new species belongs to thummi cytocomplex, (decorus-group), with chromosome set- 2n = 8 and chromosome arm combinations: AB CD EF G. Karyologically, the species is closest to Chironomus riihimaekiensis Wülker (1973). This species has very compact salivary gland chromosomes with well heterochromatinized centromere regions in chromosomes AB CD G. Several fixed homozygous inversions distinguish arm A of the species from that of C. riihimaekiensis. Arm E differs from that of C. riihimaekiensis by simple fixed homozygous inversion. Some similarities in band sequences of this arm were found with species from the decorus-group as Chironomus blaylocki Wülker et al., 2009 and C. bifurcatus (decorus-group). The position of the key constrictions in chromosome G: Nucleolar organizer (NOR) and Balbiani rings (BRs) is similar to the species of decorus-group. C. alchichica sp. n. has been found in soft sediments rich in organic matter in well mineralized waters (where conductivity >10 mS cm-1) and with a high pH (≥9). The profundal zone is inhabited only during the mixing period, when dissolved oxygen is present.

Electrode erosion in arc discharges at atmospheric pressure

NASA Technical Reports Server (NTRS)

Hardy, T. L.

1985-01-01

An experimental investigation was performed in an effort to measure and increase lifetime of electrodes in an arcjet thruster. The electrode erosion of various anode and cathode materials was measured after tests in an atmospheric pressure nitrogen arc discharge at powers less than 1 kW. A free-burning arc configuration and a constricted arc configuration were used to test the materials. Lanthanum hexboride and thoriated tungsten had low cathode erosion rates while thoriated tungsten and pure tungsten had the lowest anode erosion rates of the materials tested. Anode cooling, reverse gas flow, an external magnetic fields were all found to reduce electrode mass loss.

Utility of hepatic transaminases in children with concern for abuse.

PubMed

Lindberg, Daniel M; Shapiro, Robert A; Blood, Emily A; Steiner, R Daryl; Berger, Rachel P

2013-02-01

Routine testing of hepatic transaminases, amylase, and lipase has been recommended for all children evaluated for physical abuse, but rates of screening are widely variable, even among abuse specialists, and data for amylase and lipase testing are lacking. A previous study of screening in centers that endorsed routine transaminase screening suggested that using a transaminase threshold of 80 IU/L could improve injury detection. Our objectives were to prospectively validate the test characteristics of the 80-IU/L threshold and to determine the utility of amylase and lipase to detect occult abdominal injury. This was a retrospective secondary analysis of the Examining Siblings To Recognize Abuse research network, a multicenter study in children younger than 10 years old who underwent subspecialty evaluation for physical abuse. We determined rates of identified abdominal injuries and results of transaminase, amylase, and lipase testing. Screening studies were compared by using basic test characteristics (sensitivity, specificity) and the area under the receiver operating characteristic curve. Abdominal injuries were identified in 82 of 2890 subjects (2.8%; 95% confidence interval: 2.3%-3.5%). Hepatic transaminases were obtained in 1538 (53%) subjects. Hepatic transaminases had an area under the receiver operating characteristic curve of 0.87. A threshold of 80 IU/L yielded sensitivity of 83.8% and specificity of 83.1%. The areas under the curve for amylase and lipase were 0.67 and 0.72, respectively. Children evaluated for physical abuse with transaminase levels >80 IU/L should undergo definitive testing for abdominal injury.

Recurrent severe abdominal pain in the pediatric patient.

PubMed

Homme, James L; Foster, Ashley A

2014-05-01

Ureteropelvic junction obstruction (UPJO) is a blockage occurring at the junction of the ureter and the renal pelvis. Pediatric patients with UPJO pose a diagnostic challenge when they present to the emergency department (ED) with severe recurrent abdominal pain if there is not a level of suspicion for this condition. Our aim was to review presentation of UPJO to the ED, methods of diagnosis, and treatment of this common but often overlooked condition. We report on 2 patients, a 9-year-old and 3-year-old, who had multiple presentations to health care providers and the ED with intermittent and recurrent abdominal pain. Subsequent testing, including ultrasound (US) and computed tomography (CT) with diuretic-recreated symptoms, revealed UPJO. Open pyeloplasty was performed, resulting in complete resolution of symptoms. UPJO is an important diagnosis to consider when patients present to the ED with recurrent abdominal pain. US can be helpful in suspecting the diagnosis, but often CT, magnetic resonance urography, or diuretic scintigraphy is required for confirmation. Diuretics can be used to aid diagnostic testing by reproducing abdominal pain at the time of imaging. Referral to a urologist for open pyeloplasty is definitive treatment for this condition. Copyright © 2014 Elsevier Inc. All rights reserved.

Pupil-mimicry conditions trust in partners: moderation by oxytocin and group membership.

PubMed

Kret, Mariska E; De Dreu, Carsten K W

2017-03-15

Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to others, by contracting the muscles around their eyes and pupils. In our earlier research, we observed that interaction partners with dilating pupils are trusted more than partners with constricting pupils. But over and beyond this effect, we found that the pupil sizes of partners synchronize and that when pupils synchronously dilate, trust is further boosted. Critically, this linkage between mimicry and trust was bound to interactions between ingroup members. The current study investigates whether these findings are modulated by oxytocin and sex of participant and partner. Using incentivized trust games with partners from ingroup and outgroup whose pupils dilated, remained static or constricted, this study replicates our earlier findings. It further reveals that (i) male participants withhold trust from partners with constricting pupils and extend trust to partners with dilating pupils, especially when given oxytocin rather than placebo; (ii) female participants trust partners with dilating pupils most, but this effect is blunted under oxytocin; (iii) under oxytocin rather than placebo, pupil dilation mimicry is weaker and pupil constriction mimicry stronger; and (iv) the link between pupil constriction mimicry and distrust observed under placebo disappears under oxytocin. We suggest that pupil-contingent trust is parochial and evolved in social species in and because of group life. © 2017 The Authors.

Possible oriented transition of multiple-emulsion globules with asymmetric internal structures in a microfluidic constriction

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Li, Xiaoduan; Wang, Xiaoyong; Guan, Jing

2014-05-01

When a globule with a complete symmetry (such as simple spherical droplets and concentric double emulsions) is transiting in a constriction tube, there is only one pattern of the transition. However, for a multiple-emulsion globule with asymmetric internal structures, there are many possible patterns with different pressure drops Δp due to various initial orientations of the inner droplets. In this paper, a boundary integral method developed recently is employed to investigate numerically the possible oriented transition of a globule with two unequal inner droplets in an axisymmetric microfluidic constriction. The transition is driven by an axisymmetric Poiseuille flow with a fixed volume flow rate, and the rheological behaviors of the globule are observed carefully. When the big inner droplet is initially located in the front of the globule, the maximum pressure drop during the transition is always lower than that when it is initially placed in the rear. Thus, a tropism—whereby a globule more easily gets through the constriction when its bigger inner droplet locates in its front initially—might exist, in which the orientating stimulus is the required pressure drops. The physical explanation of this phenomenon has also been analyzed in this paper.

Allergic inflammation induces a persistent mechanistic switch in thromboxane-mediated airway constriction in the mouse

PubMed Central

Cyphert, Jaime M.; Allen, Irving C.; Church, Rachel J.; Latour, Anne M.; Snouwaert, John N.; Coffman, Thomas M.

2012-01-01

Actions of thromboxane (TXA2) to alter airway resistance were first identified over 25 years ago. However, the mechanism underlying this physiological response has remained largely undefined. Here we address this question using a novel panel of mice in which expression of the thromboxane receptor (TP) has been genetically manipulated. We show that the response of the airways to TXA2 is complex: it depends on expression of other G protein-coupled receptors but also on the physiological context of the signal. In the healthy airway, TXA2-mediated airway constriction depends on expression of TP receptors by smooth muscle cells. In contrast, in the inflamed lung, the direct actions of TXA2 on smooth muscle cell TP receptors no longer contribute to bronchoconstriction. Instead, in allergic lung disease, TXA2-mediated airway constriction depends on neuronal TP receptors. Furthermore, this mechanistic switch persists long after resolution of pulmonary inflammation. Our findings demonstrate the powerful ability of lung inflammation to modify pathways leading to airway constriction, resulting in persistent changes in mechanisms of airway reactivity to key bronchoconstrictors. Such alterations are likely to shape the pathogenesis of asthmatic lung disease. PMID:21984570

The effect of deep brain stimulation on the speech motor system.

PubMed

Mücke, Doris; Becker, Johannes; Barbe, Michael T; Meister, Ingo; Liebhart, Lena; Roettger, Timo B; Dembek, Till; Timmermann, Lars; Grice, Martine

2014-08-01

Chronic deep brain stimulation of the nucleus ventralis intermedius is an effective treatment for individuals with medication-resistant essential tremor. However, these individuals report that stimulation has a deleterious effect on their speech. The present study investigates one important factor leading to these effects: the coordination of oral and glottal articulation. Sixteen native-speaking German adults with essential tremor, between 26 and 86 years old, with and without chronic deep brain stimulation of the nucleus ventralis intermedius and 12 healthy, age-matched subjects were recorded performing a fast syllable repetition task (/papapa/, /tatata/, /kakaka/). Syllable duration and voicing-to-syllable ratio as well as parameters related directly to consonant production, voicing during constriction, and frication during constriction were measured. Voicing during constriction was greater in subjects with essential tremor than in controls, indicating a perseveration of voicing into the voiceless consonant. Stimulation led to fewer voiceless intervals (voicing-to-syllable ratio), indicating a reduced degree of glottal abduction during the entire syllable cycle. Stimulation also induced incomplete oral closures (frication during constriction), indicating imprecise oral articulation. The detrimental effect of stimulation on the speech motor system can be quantified using acoustic measures at the subsyllabic level.

A mitochondria-anchored isoform of the actin-nucleating spire protein regulates mitochondrial division

PubMed Central

Manor, Uri; Bartholomew, Sadie; Golani, Gonen; Christenson, Eric; Kozlov, Michael; Higgs, Henry; Spudich, James; Lippincott-Schwartz, Jennifer

2015-01-01

Mitochondrial division, essential for survival in mammals, is enhanced by an inter-organellar process involving ER tubules encircling and constricting mitochondria. The force for constriction is thought to involve actin polymerization by the ER-anchored isoform of the formin protein inverted formin 2 (INF2). Unknown is the mechanism triggering INF2-mediated actin polymerization at ER-mitochondria intersections. We show that a novel isoform of the formin-binding, actin-nucleating protein Spire, Spire1C, localizes to mitochondria and directly links mitochondria to the actin cytoskeleton and the ER. Spire1C binds INF2 and promotes actin assembly on mitochondrial surfaces. Disrupting either Spire1C actin- or formin-binding activities reduces mitochondrial constriction and division. We propose Spire1C cooperates with INF2 to regulate actin assembly at ER-mitochondrial contacts. Simulations support this model's feasibility and demonstrate polymerizing actin filaments can induce mitochondrial constriction. Thus, Spire1C is optimally positioned to serve as a molecular hub that links mitochondria to actin and the ER for regulation of mitochondrial division. DOI: http://dx.doi.org/10.7554/eLife.08828.001 PMID:26305500

Design and analysis of coiled fiber reinforced soft pneumatic actuator.

PubMed

Singh, Gaurav; Xiao, Chenzhang; Hsiao-Wecksler, Elizabeth T; Krishnan, Girish

2018-04-18

Fiber reinforced elastomeric enclosures (FREEs) are soft pneumatic actuators that can contract and generate forces upon pressurization. Typical engineering applications utilize FREEs in their straight cylindrical configuration and derive actuation displacement and forces from their ends. However, there are several instances in nature, such as an elephant trunk, snakes and grapevine tendrils, where a spiral configuration of muscle systems is used for gripping, thereby establishing a mechanical connection with uniform force distribution. Inspired by these examples, this paper investigates the constricting behavior of a contracting FREE actuator deployed in a spiral or coiled configuration around a cylindrical object. Force balance is used to model the blocked force of the FREE, which is then related to the constriction force using a string model. The modeling and experimental findings reveal an attenuation in the blocked force, and thus the constriction force caused by the coupling of peripheral contact forces acting in the spiral configuration. The usefulness of the coiled FREE configuration is demonstrated in a soft arm orthosis for crutch users that provides a constriction force around the forearm. This design minimizes injury risk by reducing wrist load and improving wrist posture.

Effect of Electroacupuncture on Rats with Chronic Constriction Injury-Induced Neuropathic Pain

PubMed Central

Tang, Nou-Ying; Lin, Yi-Wen; Li, Tsai-Chung; Liu, Hsu-Jan

2014-01-01

We adopt the chronic constriction injury (CCI) model to induce neuropathic pain to Spragrue-Dawley (SD) rats by ligating the right sciatic nerve of using four 4-0 chromic gut sutures and subsequently applying 2 and 15 Hz electroacupuncture (EA), respectively, to the right (ipsilateral) Zusanli (St-36) and Shangjuxu (St-37) acupoints. The results of this study are summarized as follows: (1) the differences in withdrawal latencies for the radiant heat test and total lift leg counts for the cold plate test (4°C) of the control (i.e., non-EA) and sham groups were greater than those of the 2 Hz EA (2EA) and 15 Hz EA (15EA) groups; (2) the von Frey test filament gram counts of the control and sham groups were less than those of the 2EA and 15EA groups on the 6th, 7th, 8th, 11th, 12th, and 13th day following ligation; and (3) the 2EA and 15EA groups exhibited reduced cerebral transient receptor potential vanilloid type 4 (TRPV4) expressions, although we did not observe a similar effect for cerebral TRPV1 or spinal TRPV4/TRPV1 expressions. These findings show that 2 and 15 Hz EA can reduce CCI-induced neuropathic pain, which indicates that various spinal segmental and gate effects have a crucial function in pain reduction. The relationship between EA and TRPV4/TRPV1 expression requires further study. PMID:24605047

Pupillary Light Reflexes are Associated with Autonomic Dysfunction in Bolivian Diabetics But Not Chagas Disease Patients.

PubMed

Halperin, Anthony; Pajuelo, Monica; Tornheim, Jeffrey A; Vu, Nancy; Carnero, Andrés M; Galdos-Cardenas, Gerson; Ferrufino, Lisbeth; Camacho, Marilyn; Justiniano, Juan; Colanzi, Rony; Bowman, Natalie M; Morris, Tiffany; MacDougall, Hamish; Bern, Caryn; Moore, Steven T; Gilman, Robert H

2016-06-01

Autonomic dysfunction is common in Chagas disease and diabetes. Patients with either condition complicated by cardiac autonomic dysfunction face increased mortality, but no clinical predictors of autonomic dysfunction exist. Pupillary light reflexes (PLRs) may identify such patients early, allowing for intensified treatment. To evaluate the significance of PLRs, adults were recruited from the outpatient endocrine, cardiology, and surgical clinics at a Bolivian teaching hospital. After testing for Chagas disease and diabetes, participants completed conventional autonomic testing (CAT) evaluating their cardiovascular responses to Valsalva, deep breathing, and orthostatic changes. PLRs were measured using specially designed goggles, then CAT and PLRs were compared as measures of autonomic dysfunction. This study analyzed 163 adults, including 96 with Chagas disease, 35 patients with diabetes, and 32 controls. PLRs were not significantly different between Chagas disease patients and controls. Patients with diabetes had longer latency to onset of pupil constriction, slower maximum constriction velocities, and smaller orthostatic ratios than nonpatients with diabetes. PLRs correlated poorly with CAT results. A PLR-based clinical risk score demonstrated a 2.27-fold increased likelihood of diabetes complicated by autonomic dysfunction compared with the combination of blood tests, CAT, and PLRs (sensitivity 87.9%, specificity 61.3%). PLRs represent a promising tool for evaluating subclinical neuropathy in patients with diabetes without symptomatic autonomic dysfunction. Pupillometry does not have a role in the evaluation of Chagas disease patients. © The American Society of Tropical Medicine and Hygiene.

Arnebia euchroma ointment can reduce abdominal fat thickness and abdominal circumference of overweight women: A randomized controlled study.

PubMed

Siavash, Mansour; Naseri, Mohsen; Rahimi, Mojgan

2016-01-01

Obesity is a worldwide health problem which is associated with a lot of complications. One of these comorbidities is the metabolic syndrome that is in correlation with abdominal fat thickness and waist circumference. Various methods were used to reduce abdominal fat thickness such as liposuction. A noninvasive method is the topical agent. In this study, we investigated the effectiveness of Arnebia euchroma (AE) ointment on the abdominal fat thickness. This study was a double-blind clinical trial which was done at the endocrinology clinic in Khorshid Hospital, Isfahan, Iran, in 2014. After explaining the procedure and obtaining informed consent, the candidates were randomly divided into the case and control groups. The participants of the case and control groups applied AE ointment or placebo for 6 weeks on their abdominal area. Body mass index, waist and buttock circumference, and abdominal fat thickness were measured in both case and control groups at their first visit and then at the next 2, 4, and 6 weeks. We used t -test for comparing parametric variables between groups, paired t -test for changes from baseline to final, and repeated measure ANOVA for changes at different steps. Sixty female candidates participated in this study (thirty in each group). Ten patients left the study and fifty participants finished the trial. At the end of the study, participants had a significant weight loss (2.96 ± 1.6 kg, P < 0.001) that was slightly more in the case group (3.15 ± 1.5 kg vs. 2.75 ± 1.7, P = 0.375). Abdominal circumference also decreased significantly in the participants (11.3 ± 6.7 cm, P < 0.001), but the changes were more significant in the case group (13.9 vs. 6.5 cm, P = 0.004). Similarly, abdominal fat thickness decreased significantly in the participants (2.3 ± 1.1 cm, P < 0.001), although changes were not significantly different between two groups (2.53 vs. 2.04 cm, P = 0.139). Topical AE ointment can reduce the abdominal fat thickness as well as the waist circumference without causing any side effect.

Effects of inspiratory muscle training on balance ability and abdominal muscle thickness in chronic stroke patients

PubMed Central

Oh, Dongha; Kim, Gayeong; Lee, Wanhee; Shin, Mary Myong Sook

2016-01-01

[Purpose] This study evaluated the effects of inspiratory muscle training on pulmonary function, deep abdominal muscle thickness, and balance ability in stroke patients. [Subjects] Twenty-three stroke patients were randomly allocated to an experimental (n = 11) or control group (n = 12). [Methods] The experimental group received inspiratory muscle training-based abdominal muscle strengthening with conventional physical therapy; the control group received standard abdominal muscle strengthening with conventional physical therapy. Treatment was conducted 20 minutes per day, 3 times per week for 6 weeks. Pulmonary function testing was performed using an electronic spirometer. Deep abdominal muscle thickness was measured by ultrasonography. Balance was measured using the Berg balance scale. [Results] Forced vital capacity, forced expiratory volume in 1 second, deep abdominal muscle thickness, and Berg balance scale scores were significantly improved in the experimental group than in the control group. [Conclusion] Abdominal muscle strengthening accompanied by inspiratory muscle training is recommended to improve pulmonary function in stroke patients, and may also be used as a practical adjunct to conventional physical therapy. PMID:26957739

Increased auditory startle reflex in children with functional abdominal pain.

PubMed

Bakker, Mirte J; Boer, Frits; Benninga, Marc A; Koelman, Johannes H T M; Tijssen, Marina A J

2010-02-01

To test the hypothesis that children with abdominal pain-related functional gastrointestinal disorders have a general hypersensitivity for sensory stimuli. Auditory startle reflexes were assessed in 20 children classified according to Rome III classifications of abdominal pain-related functional gastrointestinal disorders (13 irritable bowel syndrome [IBS], 7 functional abdominal pain syndrome; mean age, 12.4 years; 15 girls) and 23 control subjects (14 girls; mean age, 12.3 years) using a case-control design. The activity of 6 left-sided muscles and the sympathetic skin response were obtained by an electromyogram. We presented sudden loud noises to the subjects through headphones. Both the combined response of 6 muscles and the blink response proved to be significantly increased in patients with abdominal pain compared with control subjects. A significant increase of the sympathetic skin response was not found. Comorbid anxiety disorders (8 patients with abdominal pain) or Rome III subclassification did not significantly affect these results. This study demonstrates an objective hyperresponsivity to nongastrointestinal stimuli. Children with abdominal pain-related functional gastrointestinal disorders may have a generalized hypersensitivity of the central nervous system. Copyright 2010 Mosby, Inc. All rights reserved.

Effect of gravitation stress and hypokinesia on blood vessels of the testicle

NASA Technical Reports Server (NTRS)

Palazhchenko, E. F.

1979-01-01

Rabbits were exposed to single maximum endurable stresses of cranio-caudal direction, hypokinesia for periods of one to eight weeks, and hypokinesia followed by gravitation stresses. The stresses caused dilatation of vessels, greater sinuosity, and occasional ruptures of the walls and extravasation. The greater part of the capillaries were dilated; the greatest part constricted. In hypokinesia there was an increasing atrophy of the testes. Significant results are reported.

The Shock and Vibration Bulletin. Part 3. Structural Dynamics, Machinery Dynamics and Vibration Problems

DTIC Science & Technology

1984-06-01

and to thermopile, but with a dynamically non similar control . Response limiting was accomplished by electric heat source. The test transient measuring...pulse Improvements = Final eport, Space teats were found to be reasonably simple to and Communications Group , Hughes implement and control . The time...coolant flow components, experimental studies are generally from the core is constricted by the presence r of the control rod drive line (CRDL

Breath tests and irritable bowel syndrome

PubMed Central

Rana, Satya Vati; Malik, Aastha

2014-01-01

Breath tests are non-invasive tests and can detect H2 and CH4 gases which are produced by bacterial fermentation of unabsorbed intestinal carbohydrate and are excreted in the breath. These tests are used in the diagnosis of carbohydrate malabsorption, small intestinal bacterial overgrowth, and for measuring the orocecal transit time. Malabsorption of carbohydrates is a key trigger of irritable bowel syndrome (IBS)-type symptoms such as diarrhea and/or constipation, bloating, excess flatulence, headaches and lack of energy. Abdominal bloating is a common nonspecific symptom which can negatively impact quality of life. It may reflect dietary imbalance, such as excess fiber intake, or may be a manifestation of IBS. However, bloating may also represent small intestinal bacterial overgrowth. Patients with persistent symptoms of abdominal bloating and distension despite dietary interventions should be referred for H2 breath testing to determine the presence or absence of bacterial overgrowth. If bacterial overgrowth is identified, patients are typically treated with antibiotics. Evaluation of IBS generally includes testing of other disorders that cause similar symptoms. Carbohydrate malabsorption (lactose, fructose, sorbitol) can cause abdominal fullness, bloating, nausea, abdominal pain, flatulence, and diarrhea, which are similar to the symptoms of IBS. However, it is unclear if these digestive disorders contribute to or cause the symptoms of IBS. Research studies show that a proper diagnosis and effective dietary intervention significantly reduces the severity and frequency of gastrointestinal symptoms in IBS. Thus, diagnosis of malabsorption of these carbohydrates in IBS using a breath test is very important to guide the clinician in the proper treatment of IBS patients. PMID:24976698

Constricted glow discharge plasma source

DOEpatents

Anders, Andre; Anders, Simone; Dickinson, Michael; Rubin, Michael; Newman, Nathan

2000-01-01

A constricted glow discharge chamber and method are disclosed. The polarity and geometry of the constricted glow discharge plasma source is set so that the contamination and energy of the ions discharged from the source are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The source is suitable for applying films of nitrides such as gallium nitride and oxides such as tungsten oxide and for enriching other substances in material surfaces such as oxygen and water vapor, which are difficult process as plasma in any known devices and methods. The source can also be used to assist the deposition of films such as metal films by providing low-energy ions such as argon ions.

CoMIC, the hidden dynamics of mitochondrial inner compartments

PubMed Central

Cho, Bongki; Sun, Woong

2017-01-01

Mitochondria have evolutionarily, functionally and structurally distinct outer- (OMM) and inner-membranes (IMM). Thus, mitochondrial morphology is controlled by independent but coordinated activity of fission and fusion of the OMM and IMM. Constriction and division of the OMM are mediated by endocytosis-like machineries, which include dynamin-related protein 1 with additional cytosolic vesicle scissoring machineries such as actin filament and Dynamin 2. However, structural alteration of the IMM during mitochondrial division has been poorly understood. Recently, we found that the IMM and the inner compartments undergo transient and reversible constriction prior to the OMM division, which we termed CoMIC, Constriction of Mitochondrial Inner Compartment. In this short review, we further discuss the evolutionary perspective and the regulatory mechanism of CoMIC during mitochondrial division. PMID:28803609

CoMIC, the hidden dynamics of mitochondrial inner compartments.

PubMed

Cho, Bongki; Sun, Woong

2017-12-01

Mitochondria have evolutionarily, functionally and structurally distinct outer- (OMM) and inner-membranes (IMM). Thus, mitochondrial morphology is controlled by independent but coordinated activity of fission and fusion of the OMM and IMM. Constriction and division of the OMM are mediated by endocytosis-like machineries, which include dynamin-related protein 1 with additional cytosolic vesicle scissoring machineries such as actin filament and Dynamin 2. However, structural alteration of the IMM during mitochondrial division has been poorly understood. Recently, we found that the IMM and the inner compartments undergo transient and reversible constriction prior to the OMM division, which we termed CoMIC, Constriction of Mitochondrial Inner Compartment. In this short review, we further discuss the evolutionary perspective and the regulatory mechanism of CoMIC during mitochondrial division. [BMB Reports 2017; 50(12): 597-598].

Two-dimensional speckle tracking cardiac mechanics and constrictive pericarditis: systematic review.

PubMed

Madeira, Marta; Teixeira, Rogério; Costa, Marco; Gonçalves, Lino; Klein, Allan L

2016-10-01

Transthoracic echocardiography has a pivotal role in the diagnosis of constrictive pericarditis (CP). In addition to the classic M-mode, two-dimensional and Doppler indices, newer methodologies designed to evaluate myocardial mechanics, such as two-dimensional speckle tracking echocardiography (2DSTE), provide additional diagnostic and clinical information in the context of CP. Research has demonstrated that cardiac mechanics can improve echocardiographic diagnostic accuracy of CP and aid in differentiating between constrictive and restrictive ventricular physiology. 2DSTE can also be used to assess the success of pericardiectomy and its impact on atrial and ventricular mechanics. In the course of this review, we describe cardiac mechanics in patients with CP and summarize the influence of pericardiectomy on atrial and ventricular mechanics assessed using 2DSTE. © 2016, Wiley Periodicals, Inc.

Managing acute abdominal pain in pediatric patients: current perspectives

PubMed Central

Hijaz, Nadia M; Friesen, Craig A

2017-01-01

Acute abdominal pain in pediatric patients has been a challenge for providers because of the nonspecific nature of symptoms and difficulty in the assessment and physical examination in children. Although most children with acute abdominal pain have self-limited benign conditions, pain may be a manifestation of an urgent surgical or medical condition where the biggest challenge is making a timely diagnosis so that appropriate treatment can be initiated without any diagnostic delays that increase morbidity. This is weighed against the need to decrease radiation exposure and avoid unnecessary operations. Across all age groups, there are numerous conditions that present with abdominal pain ranging from a very simple viral illness to a life-threatening surgical condition. It is proposed that the history, physical examination, laboratory tests, and imaging studies should initially be directed at differentiating surgical versus nonsurgical conditions both categorized as urgent versus nonurgent. The features of the history including patient’s age, physical examination focused toward serious conditions, and appropriate tests are highlighted in the context of making these differentiations. Initial testing and management is also discussed with an emphasis on making use of surgeon and radiologist consultation and the need for adequate follow-up and reevaluation of the patient. PMID:29388612

[Fascioliasis and brucellosis in same patient].

PubMed

Deveci, Özcan; Aslan, Emel; Tekin, Alicem; Toka Özer, Türkan; Tekin, Recep; Bozkurt, Fatma; Çetinçakmak, Mehmet Guli

2014-01-01

Brucellosis is a zoonotic infectious disease that can affect many organs and systems and leads to very different clinical circumstances. Brucellosis is rare in association with various infectious agents. Fascioliasis is a zoonotic disease caused by Fasciola hepatica, popularly referred to as a large leaf-shaped liver fluke. This case is a 39-year-old male patient, and his complaints began a week ago, which were chills, fever, abdominal pain, nausea, vomiting, weakness, sweating, and widespread pain. The patient was considered brucellosis in the preliminary diagnosis. Rose Bengal test and Wright test (1/640) were detected as positive. Due to patients having elevated liver enzymes, abdominal ultrasound was taken. A liver lesion was seen with abdominal ultrasound. So, abdominal computed tomography (CT) was taken. The CT result report came in the form that at the left lobe of the liver segment 2, largely necrosis that showed no contrast enhancement, approximately 61x63 mm in size (compatible with fascioliasis) is viewed. The patient's IHA test results, required for fascioliasis, were detected as 1/320 positive. Especially for zoonotic diseases in areas with high endemicity, it should be considered that more than one infectious agent can be present together in high-risk patients.

[The physical examination - a vanishing art?

PubMed

Tönnesmann, Ernst; Goltz, Diane; Lewalter, Thorsten; Welz, Armin

2016-10-01

This report describes the case of a 63-year-old female patient who presented with progressive dyspnea to a specialized internal medicine practice. Prior consultations with her primary care physician and a cardiologist followed by hospitalizations in an acute care hospital and in a specialist clinic for cardiology had not yielded a conclusive diagnosis. During the physical examination, significant bilateral lower extremity edema, as well as pronounced jugular venous distention was noted while in a seated position. This prompted further targeted diagnostic examination and testing and resulted in the final diagnosis of constrictive pericarditis of tuberculous origin.The establishment of the diagnosis is discussed in the context of increasingly technologized medical practice, where clinical skills and the significance of the patient history and physical examination are declining. In addition, we discuss the problem of less common diseases of the myo- and pericardium with primarily diastolic (constrictive or restrictive) dysfunction being overlooked in routine cardiological diagnostic procedures, with a focus on coronary heart disease, valve disorders and the impairment of systolic ventricular function ("ejection fraction"). © Georg Thieme Verlag KG Stuttgart · New York.

Anatomo-radiological correlation using 18-FDG-PET in abdominal sepsis model in rats. A preliminary study.

PubMed

Azevedo, Ítalo Medeiros; Carvalho, Marília Daniela Ferreira; Nascimento, Rafael Pereira; Macedo, Robson; Aquino, Mônica Raquel de Souza; Medeiros, Aldo Cunha

2017-03-01

To examine a correlation of micro-PET images with photographic images of the digestive organs in abdominal sepsis model. Male Wistar rats weighing 265±18g were used. Abdominal sepsis was induced by ligature and cecal puncture. Micro-PET Images from abdominal cavity septic foci were obtained using 18-Fluoro-deoxyglucose, looking for a correlation with photographic images of abdominal cavity organs. Pearson's correlation test was used. The mean standard uptake values (SUV) and lesion areas were 2.58±0.63SUVbwg/ml and 546.87±300.95mm2, respectively. There was a strong positive correlation between the two variables (r=0.863, p=0.137), which resulted in a coefficient of determination r2?0.75, meaning that 75% of SUV variation is explained by the lesion areas of digestive organs. Micro-PET allows high throughput assessment of lesion count and volume in pre-clinical rat model of CPL abdominal sepsis.

Method matters: Experimental evidence for shorter avian sperm in faecal compared to abdominal massage samples

PubMed Central

Cockburn, Glenn; Sánchez-Tójar, Alfredo; Løvlie, Hanne; Schroeder, Julia

2017-01-01

Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males' faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically. PMID:28813481

Clinical application of entire gastrointestinal barium meal combined with multi-temporal abdominal films in patients with intestinal neuronal dysplasia type B.

PubMed

Li, Xiao-Yun; Li, Xiao-Gang; Du, Ming-Guo; Chen, Zhi-Dan; Tao, Zheng-Gui; Liao, Xiao-Feng

2013-01-01

To report and evaluate the application of entire gastrointestinal barium meal combined with multi-temporal abdominal films in the diagnosis of patients with intestinal neuronal dysplasia type B (IND type B). Thirty-six patients with symptoms of long-standing constipation were enrolled in this study. The study took place at the Department of General Surgery, Xiangyang Central Hospital, Hubei Province, China from July 2007 to October 2012. All of them had already been subjected to the tests of barium enema and anorectal manometry and were suspected to be IND type B, but were not confirmed by mucous membrane acetylcholinesterase determination. All underwent the entire gastrointestinal barium meal combined with multi-temporal abdominal films. The data was collected and then analyzed retrospectively. After entire gastrointestinal barium meal combined with multi-temporal abdominal films, 30 out of 36 cases in this group were diagnosed with intestinal neuronal diseases, and then were treated with appropriate surgical treatment. The postoperative pathological diagnosis was IND type B. The other 6 patients in this group still could not be diagnosed explicitly after the test; thus, we treated them with conservative treatment. Entire gastrointestinal barium meal combined with multi-temporal abdominal films has the advantage of being able to test the gastrointestinal transfer capabilities and to find physiological and pathological changes simultaneously. It could provide important proof for the diagnosis of patients with intestinal neuronal dysplasia type B.

Development of a reliable simulation-based test for diagnostic abdominal ultrasound with a pass/fail standard usable for mastery learning.

PubMed

Østergaard, Mia L; Nielsen, Kristina R; Albrecht-Beste, Elisabeth; Konge, Lars; Nielsen, Michael B

2018-01-01

This study aimed to develop a test with validity evidence for abdominal diagnostic ultrasound with a pass/fail-standard to facilitate mastery learning. The simulator had 150 real-life patient abdominal scans of which 15 cases with 44 findings were selected, representing level 1 from The European Federation of Societies for Ultrasound in Medicine and Biology. Four groups of experience levels were constructed: Novices (medical students), trainees (first-year radiology residents), intermediates (third- to fourth-year radiology residents) and advanced (physicians with ultrasound fellowship). Participants were tested in a standardized setup and scored by two blinded reviewers prior to an item analysis. The item analysis excluded 14 diagnoses. Both internal consistency (Cronbach's alpha 0.96) and inter-rater reliability (0.99) were good and there were statistically significant differences (p < 0.001) between all four groups, except the intermediate and advanced groups (p = 1.0). There was a statistically significant correlation between experience and test scores (Pearson's r = 0.82, p < 0.001). The pass/fail-standard failed all novices (no false positives) and passed all advanced (no false negatives). All intermediate participants and six out of 14 trainees passed. We developed a test for diagnostic abdominal ultrasound with solid validity evidence and a pass/fail-standard without any false-positive or false-negative scores. • Ultrasound training can benefit from competency-based education based on reliable tests. • This simulation-based test can differentiate between competency levels of ultrasound examiners. • This test is suitable for competency-based education, e.g. mastery learning. • We provide a pass/fail standard without false-negative or false-positive scores.

[When should a patient with abdominal pain be referred to the emergency ward?].

PubMed

de Saussure, Wassila Oulhaci; Andereggen, Elisabeth; Sarasin, François

2010-08-25

When should a patient with abdominal pain be referred to the emergency ward? The following goals must be achieved upon managing patients with acute abdominal pain: 1) identify vital emergency situations; 2) detect surgical conditions that require emergency referral without further diagnostic procedures; 3) in "non surgical acute abdomen patients" perform appropriate diagnostic procedures, or in selected cases delay tests and reevaluate the patient after an observation period, after which a referral decision is made. Clues from the history and physical examination are critical to perform this evaluation. A good knowledge of the most frequent acute abdominal conditions, and identifying potential severity criteria allow an appropriate management and decision about emergency referral.

Risk Assessment of Abdominal Wall Thickness Measured on Pre-Operative Computerized Tomography for Incisional Surgical Site Infection after Abdominal Surgery.

PubMed

Tongyoo, Assanee; Chatthamrak, Putipan; Sriussadaporn, Ekkapak; Limpavitayaporn, Palin; Mingmalairak, Chatchai

2015-07-01

The surgical site infection (SSI) is a common complication of abdominal operation. It relates to increased hospital stay, increased healthcare cost, and decreased patient's quality of life. Obesity, usually defined by BMI, is known as one of the risks of SSI. However, the thickness of subcutaneous layers of abdominal wall might be an important local factor affecting the rate of SSI after the abdominal operations. The objective of this study is to assess the importance of the abdominal wall thickness on incisional SSI rate. The subjects of the present study were patients who had undergone major abdominal operations at Thammasat University Hospital between June 2013 and May 2014, and had been investigated with CT scans before their operations. The demographic data and clinical information of these patients were recorded. The thickness ofsubcutaneous fatty tissue from skin down to the most superficial layer of abdominal wall muscle at the surgical site was measured on CT images. The wound infectious complication was reviewed and categorized as superficial and deep incisional SSIfollowing the definition from Centersfor Disease Control and Prevention (CDC) guidelines. The significance ofeach potentialfactors on SSI rates was determined separately with student t-test for quantitative data and χ2-test for categorical data. Then all factors, which had p < 0.10, were included into the multivariate logistic regression analysis and were analyzed with significance at p < 0.05. One hundred and thirty-nine patients were included in this study. They all underwent major abdominal surgery and had had pre-operative CTscans. Post-operative SSI was 25.2% (35/139), superficial and deep types in 27 and 8 patients, respectively. The comparison of abdominal wall thickness between patients with and without infection was significantly different (20.0 ± 8.4 mm and 16.0 ± 7.2 mm, respectively). When the thickness at 20 mm was used as the cut-off value, 43 of 139 patients had abdominal wall thickness ≥ 20 mm. The incidence of SSI of the thickness ±20 mm group was 37.2% (16/43) and of the less thickness group was 19.8% (19/96), with p < 0.05. The univariate analysis revealed that abdominal wall thickness ≥ 20 mm, body weight ≥ 60 kg, and wound classification were the important factors related to SSI after the abdominal operation. However, only abdominal wall thickness and wound classification were still significant by multivariate analysis. The findings of this study confirmed the significance of the subcutaneous thickness of abdominal wall at the surgical site on the incidence of incisional SSI. The thickness ≥ 20 mm had an effect on increasing post operative SSI rate especially in contaminated operations. These findings could be helpful in making healthcare providers fully aware and thus exercise special attention in wound care or even develop new modalities to prevent SSI in patients with the aforementioned risks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ledee, Dolena R.; Smith, Lincoln; Kajimoto, Masaki

Pressure overload cardiac hypertrophy alters substrate metabolism. Prior work showed that myocardial inactivation of c-Myc (Myc) attenuated hypertrophy and decreased expression of glycolytic genes after aortic constriction. Accordingly, we hypothesize that Myc regulates substrate preferences for the citric acid cycle during pressure overload hypertrophy from transverse aortic constriction (TAC) and that these metabolic changes impact cardiac function and growth. To test this hypothesis, we subjected FVB mice with cardiac specific, inducible Myc inactivation (MycKO-TAC) and non-transgenic littermates (Cont-TAC) to transverse aortic constriction (n=7/group). A separate group underwent sham surgery (Sham, n=5). After two weeks, function was measured in isolated workingmore » hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketones and unlabeled glucose and insulin. Western blots were used to evaluate metabolic enzymes. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. Compared to Sham, Cont-TAC had increased free fatty acid fractional contribution with a concurrent decrease in unlabeled (presumably glucose) contribution. Myc inactivation (MycKO-TAC) inhibited these metabolic changes. Hypertrophy in general increased protein levels of PKM2; however this change was not linked to Myc status. Protein post-translation modification by O-GlcNAc was significantly greater in Cont-TAC versus both Sham and MycKO-TAC. In conclusion, Myc regulates substrate utilization during early pressure overload hypertrophy. Our results show that the metabolic switch during hypertrophy is not necessary to maintain cardiac function, but it may be important mechanism to promote cardiomyocyte growth. Myc also regulates protein O-GlcNAcylation during hypertrophy.« less

Effects of exposure to intermittent versus continuous red light on human circadian rhythms, melatonin suppression, and pupillary constriction.

PubMed

Ho Mien, Ivan; Chua, Eric Chern-Pin; Lau, Pauline; Tan, Luuan-Chin; Lee, Ivan Tian-Guang; Yeo, Sing-Chen; Tan, Sara Shuhui; Gooley, Joshua J

2014-01-01

Exposure to light is a major determinant of sleep timing and hormonal rhythms. The role of retinal cones in regulating circadian physiology remains unclear, however, as most studies have used light exposures that also activate the photopigment melanopsin. Here, we tested the hypothesis that exposure to alternating red light and darkness can enhance circadian resetting responses in humans by repeatedly activating cone photoreceptors. In a between-subjects study, healthy volunteers (n = 24, 21-28 yr) lived individually in a laboratory for 6 consecutive days. Circadian rhythms of melatonin, cortisol, body temperature, and heart rate were assessed before and after exposure to 6 h of continuous red light (631 nm, 13 log photons cm(-2) s(-1)), intermittent red light (1 min on/off), or bright white light (2,500 lux) near the onset of nocturnal melatonin secretion (n = 8 in each group). Melatonin suppression and pupillary constriction were also assessed during light exposure. We found that circadian resetting responses were similar for exposure to continuous versus intermittent red light (P = 0.69), with an average phase delay shift of almost an hour. Surprisingly, 2 subjects who were exposed to red light exhibited circadian responses similar in magnitude to those who were exposed to bright white light. Red light also elicited prolonged pupillary constriction, but did not suppress melatonin levels. These findings suggest that, for red light stimuli outside the range of sensitivity for melanopsin, cone photoreceptors can mediate circadian phase resetting of physiologic rhythms in some individuals. Our results also show that sensitivity thresholds differ across non-visual light responses, suggesting that cones may contribute differentially to circadian resetting, melatonin suppression, and the pupillary light reflex during exposure to continuous light.

Tidal stretches do not modulate responsiveness of intact airways in vitro

PubMed Central

Szabo, Thomas L.; Suki, Béla; Lutchen, Kenneth R.

2010-01-01

Studies on isolated tracheal airway smooth muscle (ASM) strips have shown that length/force fluctuations, similar to those likely occurring during breathing, will mitigate ASM contractility. These studies conjecture that, solely by reducing length oscillations on a healthy, intact airway, one can create airway hyperresponsiveness, but this has never been explicitly tested. The intact airway has additional complexities of geometry and structure that may impact its relevance to isolated ASM strips. We examined the role of transmural pressure (Ptm) fluctuations of physiological amplitudes on the responsiveness of an intact airway. We developed an integrated system utilizing ultrasound imaging to provide real-time measurements of luminal radius and wall thickness over the full length of an intact airway (generation 10 and below) during Ptm oscillations. First, airway constriction dynamics to cumulative acetylcholine (ACh) doses (10−7 to 10−3 M) were measured during static and dynamic Ptm protocols. Regardless of the breathing pattern, the Ptm oscillation protocols were ineffective in reducing the net level of constriction for any ACh dose, compared with the static control (P = 0.225–0.793). Next, Ptm oscillations of increasing peak-to-peak amplitude were applied subsequent to constricting intact airways under static conditions (5.0-cmH2O Ptm) with a moderate ACh dose (10−5 M). Peak-to-peak Ptm oscillations ≤5.0 cmH2O resulted in no statistically significant bronchodilatory response (P = 0.429 and 0.490). Larger oscillations (10 cmH2O, peak to peak) produced modest dilation of 4.3% (P = 0.009). The lack of modulation of airway responsiveness by Ptm oscillations in intact, healthy airways suggests that ASM level mechanisms alone may not be the sole determinant of airway responsiveness. PMID:20431023

Polycystin-1 Is a Cardiomyocyte Mechanosensor That Governs L-Type Ca2+ Channel Protein Stability.

PubMed

Pedrozo, Zully; Criollo, Alfredo; Battiprolu, Pavan K; Morales, Cyndi R; Contreras-Ferrat, Ariel; Fernández, Carolina; Jiang, Nan; Luo, Xiang; Caplan, Michael J; Somlo, Stefan; Rothermel, Beverly A; Gillette, Thomas G; Lavandero, Sergio; Hill, Joseph A

2015-06-16

L-type calcium channel activity is critical to afterload-induced hypertrophic growth of the heart. However, the mechanisms governing mechanical stress-induced activation of L-type calcium channel activity are obscure. Polycystin-1 (PC-1) is a G protein-coupled receptor-like protein that functions as a mechanosensor in a variety of cell types and is present in cardiomyocytes. We subjected neonatal rat ventricular myocytes to mechanical stretch by exposing them to hypo-osmotic medium or cyclic mechanical stretch, triggering cell growth in a manner dependent on L-type calcium channel activity. RNAi-dependent knockdown of PC-1 blocked this hypertrophy. Overexpression of a C-terminal fragment of PC-1 was sufficient to trigger neonatal rat ventricular myocyte hypertrophy. Exposing neonatal rat ventricular myocytes to hypo-osmotic medium resulted in an increase in α1C protein levels, a response that was prevented by PC-1 knockdown. MG132, a proteasomal inhibitor, rescued PC-1 knockdown-dependent declines in α1C protein. To test this in vivo, we engineered mice harboring conditional silencing of PC-1 selectively in cardiomyocytes (PC-1 knockout) and subjected them to mechanical stress in vivo (transverse aortic constriction). At baseline, PC-1 knockout mice manifested decreased cardiac function relative to littermate controls, and α1C L-type calcium channel protein levels were significantly lower in PC-1 knockout hearts. Whereas control mice manifested robust transverse aortic constriction-induced increases in cardiac mass, PC-1 knockout mice showed no significant growth. Likewise, transverse aortic constriction-elicited increases in hypertrophic markers and interstitial fibrosis were blunted in the knockout animals PC-1 is a cardiomyocyte mechanosensor that is required for cardiac hypertrophy through a mechanism that involves stabilization of α1C protein. © 2015 American Heart Association, Inc.

Alterations to Swallowing Physiology as the Result of Effortful Swallowing in Healthy Seniors.

PubMed

Molfenter, Sonja M; Hsu, Chuan-Ya; Lu, Ying; Lazarus, Cathy L

2018-06-01

A significant proportion of healthy seniors report difficulty swallowing, thought to result from age-related decline in muscle bulk/function. Effortful Swallowing (ES) is used both as a compensatory maneuver to improve pharyngeal propulsion/clearance and has been proposed as an exercise to improve pharyngeal strength. This study sought to quantify the immediate kinematic, temporal, and functional changes during an ES maneuver to quantify its exercise potential to combat age-related changes in swallowing. Videofluoroscopy data were collected from 44 healthy seniors (21 male) over 65 years old (mean = 76.9, SD = 7.1). Each participant swallowed six 5 ml boluses of Varibar nectar-thick liquids: three with regular effort and three using ES. Individual swallows (n = 260) were measured on pharyngeal constriction, pharyngeal shortening, laryngeal closure duration, hyoid movement duration, UES opening duration, stage transition duration, pharyngeal transit time, pharyngeal response duration, Normalized Residue Ratio Scale (NRRS), and the Penetration-Aspiration Scale (PAS). Non-parametric Wilcoxon Rank Sum for repeated measures tested the effect of ES on each outcome. Exact p-values were calculated based on permutation methods, individual p values < 0.008 was deemed to be significant. The ES maneuver significantly prolonged all temporal variables. While we found no significant differences for pharyngeal constriction, significantly less (i.e., worse) pharyngeal shortening was observed in ES condition compared with regular effort swallows. Further, significantly worse pyriform sinus residue (NRRSv) was observed in the ES condition. No differences between ES and regular effort swallows were noted for pharyngeal constriction, NRRSv or PAS. We speculate that these negative manifestations of worse kinematics (less pharyngeal shortening) and function (increase in NRRSp) may be the result of forced volitional manipulation of swallowing in the ES condition in an otherwise normal elderly swallow.

Electrothermal flow effects in insulating (electrodeless) dielectrophoresis systems.

PubMed

Hawkins, Benjamin G; Kirby, Brian J

2010-11-01

We simulate electrothermally induced flow in polymeric, insulator-based dielectrophoresis (iDEP) systems with DC-offset, AC electric fields at finite thermal Péclet number, and we identify key regimes where electrothermal (ET) effects enhance particle deflection and trapping. We study a single, two-dimensional constriction in channel depth with parametric variations in electric field, channel geometry, fluid conductivity, particle electrophoretic (EP) mobility, and channel electroosmotic (EO) mobility. We report the effects of increasing particle EP mobility, channel EO mobility, and AC and DC field magnitudes on the mean constriction temperature and particle behavior. Specifically, we quantify particle deflection and trapping, referring to the deviation of particles from their pathlines due to dielectrophoresis as they pass a constriction and the stagnation of particles due to negative dielectrophoresis near a constriction, respectively. This work includes the coupling between fluid, heat, and electromagnetic phenomena via temperature-dependent physical parameters. Results indicate that the temperature distribution depends strongly on the fluid conductivity and electric field magnitude, and particle deflection and trapping depend strongly on the channel geometry. Electrothermal (ET) effects perturb the EO flow field, creating vorticity near the channel constriction and enhancing the deflection and trapping effects. ET effects alter particle deflection and trapping responses in insulator-based dielectrophoresis devices, especially at intermediate device aspect ratios (2 ≤ r ≤ 7) in solutions of higher conductivity (σ m ≥ 1 × 10(-3)S/m). The impact of ET effects on particle deflection and trapping are diminished when particle EP mobility or channel EO mobility is high. In almost all cases, ET effects enhance negative dielectrophoretic particle deflection and trapping phenomena. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Experimental investigation on the vascular thermal response to near-infrared laser pulses.

PubMed

Li, Dong; Chen, Bin; Wu, Wenjuan; Ying, Zhaoxia

2017-12-01

Port wine stains (PWS) are congenital vascular malformations that progressively darken and thicken with age. To improve the effect of laser therapy in clinical practice, thermal response of blood vessel to a 1064 nm Nd:YAG laser with controlled energy doses and pulse durations was evaluated using the dorsal skin chamber model. A total of 137 vessels with 30-300 μm diameters were selected from the dorsal skin of the mouse to match those capillaries in port wine stains. Experimental results showed that the thermal response of blood vessels to 1064 nm laser irradiation can be classified as follows: vessel dilation, coagulation, constriction with decreased diameter, complete constriction, hemorrhage, and collagen damage with increasing laser radiant exposure. In most cases, that is, 83 of 137 blood vessels (60.6%), Nd:YAG laser irradiation was characterized by complete constriction (immediate blood vessel disappearance). To reveal the possible damage mechanisms and evaluate blood vessel photocoagulation patterns, theoretical investigation using bioheat transfer equation was conducted in mouse skin with a depth of 1000 μm. Complete constriction as the dominant thermal response as evidenced by uniform blood heating within the vessel lumen was noted in both experimental observation and theoretical investigation. To achieve the ideal clinical effect using the Nd:YAG laser treatment, the radiant exposure should not only be high enough to induce complete constriction of the blood vessels but also controlled carefully to avoid surrounding collagen damage. The short pulse duration of 1-3 ms is better than long pulse durations because hemorrhaging of small capillaries is occasionally observed postirradiation with pulse durations longer than 10 ms.

A microperfusion study of sucrose movement across the rat proximal tubule during renal vein constriction

PubMed Central

Bank, Norman; Yarger, William E.; Aynedjian, Hagop S.

1971-01-01

Constriction of the renal vein has been shown to inhibit net sodium and water reabsorption by the rat proximal tubule. The mechanism is unknown but might be the result of inhibition of the active sodium pump induced by changes in the interstitial fluid compartment of the kidney, or to enhanced passive backflux of sodium and water into the cell or directly into the tubular lumen. Since passive movement of solutes across epithelial membranes is determined in part by the permeability characteristics of the epithelium, an increase in the permeability of the proximal tubule during venous constriction would suggest that enhanced passive flux is involved in the inhibition of reabsorption. In the present experiments, isolated segments of rat proximal convoluted tubules were microperfused in vivo with saline while the animals were receiving 14C-labeled sucrose intravenously. In normal control animals, no sucrose was detected in the majority of the collected tubular perfusates. In rats with renal vein constriction (RVC), however, sucrose consistently appeared in the tubular perfusates. The rate of inflow of sucrose correlated with the length of the perfused segment, estimated by fractional water reabsorption. In another group of animals with renal vein constriction, inulin-14C was given intravenously and the proximal tubules similarly microperfused. Inulin did not appear in the majority of collected perfusates in these animals. These observations indicate that a physiological alteration in the permeability of the proximal tubule occurs during RVC. Such an increase in permeability is consistent with the view that enhanced passive extracellular back-flux plays a role in the reduction of net sodium and water reabsorption in this experimental condition. PMID:5540167

Endothelial Nitric Oxide Mediates Caffeine Antagonism of Alcohol-Induced Cerebral Artery Constriction

PubMed Central

Chang, Jennifer; Fedinec, Alexander L.; Kuntamallappanavar, Guruprasad; Leffler, Charles W.; Bukiya, Anna N.

2016-01-01

Despite preventive education, the combined consumption of alcohol and caffeine (particularly from “energy drinks”) continues to rise. Physiologic perturbations by separate intake of ethanol and caffeine have been widely documented. However, the biologic actions of the alcohol-caffeine combination and their underlying subcellular mechanisms have been scarcely studied. Using intravital microscopy on a closed-cranial window and isolated, pressurized vessels, we investigated the in vivo and in vitro action of ethanol-caffeine mixtures on cerebral arteries from rats and mice, widely recognized models to address cerebrovascular pathophysiology and pharmacology. Caffeine at concentrations found in human circulation after ingestion of one to two cups of coffee (10 µM) antagonized the endothelium-independent constriction of cerebral arteries evoked by ethanol concentrations found in blood during moderate-heavy alcohol intoxication (40–70 mM). Caffeine antagonism against alcohol was similar whether evaluated in vivo or in vitro, suggesting independence of systemic factors and drug metabolism, but required a functional endothelium. Moreover, caffeine protection against alcohol increased nitric oxide (NO•) levels over those found in the presence of ethanol alone, disappeared upon blocking NO• synthase, and could not be detected in pressurized cerebral arteries from endothelial nitric-oxide synthase knockout (eNOS−/−) mice. Finally, incubation of de-endothelialized cerebral arteries with the NO• donor sodium nitroprusside (10 µM) fully restored the protective effect of caffeine. This study demonstrates for the first time that caffeine antagonizes ethanol-induced cerebral artery constriction and identifies endothelial NO• as the critical caffeine effector on smooth muscle targets. Conceivably, situations that perturb endothelial function and/or NO• availability will critically alter caffeine antagonism of alcohol-induced cerebrovascular constriction without significantly disrupting endothelium-independent, alcohol-induced cerebral artery constriction itself. PMID:26555891

THE STATE OF THE VESSELS OF THE MESENTERY IN SHOCK PRODUCED BY CONSTRICTING THE LIMBS AND THE BEHAVIOR OF THE VESSELS FOLLOWING HEMORRHAGE

PubMed Central

Page, Irvine H.; Abell, Richard G.

1943-01-01

1. Direct observations of the arteries, arterioles, capillaries, veins, and lymphatics in the mesentery of anesthetized cats put into shock by incomplete occlusion of the circulation of the limbs showed that: (a) Marked constriction of the arteries and arterioles, produced by muscular contraction, occurred usually within an hour after incomplete occlusion of the limbs, lasted several hours, and finally gave way in most instances to relaxation an hour or more before death. The constriction reduced the blood supply to the mesentery and intestine and the venous return from them. It did not, however, interrupt the blood flow. No pooling or stagnation of blood was seen even as a terminal phenomenon. (b) The veins of the mesentery also became constricted but showed less tendency to dilate as death approached. The lymphatics likewise became somewhat narrowed. Even during the terminal stage the leukocytes moved along without change in shape or sticking to the walls of the capillaries or venules. (c) Hematocrit determinations showed progressive hemoconcentration of moderate degree. (d) Autopsy usually showed the presence of small hemorrhages in many parts of the body, especially the heart, liver, spleen, and lungs. (e) Bilateral nephrectomy, suprarenalectomy, and pancreatectomy did not significantly alter the morphological picture elicited by shock induced by restriction of the circulation to the limbs. 2. Removal of large amounts of blood was always followed within a short time by constriction of arteries, arterioles, veins, and lymphatics of the mesentery. 3. Fall in arterial pressure produced by pithing was not accompanied by change in diameter of the arteries, arterioles, veins, or lymphatics, or by blanching of the mesentery or gut. PMID:19871278

Multi-atlas segmentation for abdominal organs with Gaussian mixture models

NASA Astrophysics Data System (ADS)

Burke, Ryan P.; Xu, Zhoubing; Lee, Christopher P.; Baucom, Rebeccah B.; Poulose, Benjamin K.; Abramson, Richard G.; Landman, Bennett A.

2015-03-01

Abdominal organ segmentation with clinically acquired computed tomography (CT) is drawing increasing interest in the medical imaging community. Gaussian mixture models (GMM) have been extensively used through medical segmentation, most notably in the brain for cerebrospinal fluid / gray matter / white matter differentiation. Because abdominal CT exhibit strong localized intensity characteristics, GMM have recently been incorporated in multi-stage abdominal segmentation algorithms. In the context of variable abdominal anatomy and rich algorithms, it is difficult to assess the marginal contribution of GMM. Herein, we characterize the efficacy of an a posteriori framework that integrates GMM of organ-wise intensity likelihood with spatial priors from multiple target-specific registered labels. In our study, we first manually labeled 100 CT images. Then, we assigned 40 images to use as training data for constructing target-specific spatial priors and intensity likelihoods. The remaining 60 images were evaluated as test targets for segmenting 12 abdominal organs. The overlap between the true and the automatic segmentations was measured by Dice similarity coefficient (DSC). A median improvement of 145% was achieved by integrating the GMM intensity likelihood against the specific spatial prior. The proposed framework opens the opportunities for abdominal organ segmentation by efficiently using both the spatial and appearance information from the atlases, and creates a benchmark for large-scale automatic abdominal segmentation.

Influence of catch-up growth on abdominal fat distribution in very low birth weight children - cohort study.

PubMed

Alves, João Guilherme; Vasconcelos, Sarita Amorim; de Almeida, Tais Sá; Lages, Raquel; Just, Eduardo

2015-01-01

A rapid catch-up growth in very low birth weight has been associated both with a higher height growth and a higher risk to metabolic disturbances, including insulin resistance and its consequences. Abdominal fat distribution in early postnatal life may play a role in these outcomes and can help in addressing this neonatal dilemma. This study aimed to compare abdominal fat distribution among very low birth weight (VLBW) children with and without rapid catch-up growth. A cohort study followed 86 VLBW (<1500) children born in Brazil, during the first 3 years of life. Rapid catch-up growth was considered as an increased in length >2 Z score during the first year of life. Abdominal subcutaneous and preperitoneal fat thickness was determined by ultrasound. χ²-Test and Student's t-test were used to compare the groups. A total of 79 VLBW children completed the study, of whom 22 (27.8%) showed rapid catch-up growth. Abdominal subcutaneous and preperitoneal fat thickness showed no differences among children with or without rapid catch-up growth at 3.3 mm vs. 3.8 mm, respectively (p=0.79) and 4.0 mm vs. 4.0 mm (p=0.55), respectively. VLBW children with rapid catch-up growth were also taller. Rapid catch-up growth during the first year of life in VLBW children does not seem to change abdominal fat distribution until the third year of life.

Automated control of linear constricted plasma source array

DOEpatents

Anders, Andre; Maschwitz, Peter A.

2000-01-01

An apparatus and method for controlling an array of constricted glow discharge chambers are disclosed. More particularly a linear array of constricted glow plasma sources whose polarity and geometry are set so that the contamination and energy of the ions discharged from the sources are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The quality of film along deposition "tracks" opposite the plasma sources can be measured and compared to desired absolute or relative values by optical and/or electrical sensors. Plasma quality can then be adjusted by adjusting the power current values, gas feed pressure/flow, gas mixtures or a combination of some or all of these to improve the match between the measured values and the desired values.

Quantum transport through MoS2 constrictions defined by photodoping.

PubMed

Epping, Alexander; Banszerus, Luca; Güttinger, Johannes; Krückeberg, Luisa; Watanabe, Kenji; Taniguchi, Takashi; Hassler, Fabian; Beschoten, Bernd; Stampfer, Christoph

2018-05-23

We present a device scheme to explore mesoscopic transport through molybdenum disulfide (MoS 2 ) constrictions using photodoping. The devices are based on van-der-Waals heterostructures where few-layer MoS 2 flakes are partially encapsulated by hexagonal boron nitride (hBN) and covered by a few-layer graphene flake to fabricate electrical contacts. Since the as-fabricated devices are insulating at low temperatures, we use photo-induced remote doping in the hBN substrate to create free charge carriers in the MoS 2 layer. On top of the device, we place additional metal structures, which define the shape of the constriction and act as shadow masks during photodoping of the underlying MoS 2 /hBN heterostructure. Low temperature two- and four-terminal transport measurements show evidence of quantum confinement effects.

An Actin-Dependent Step in Mitochondrial Fission Mediated by the ER-Associated Formin INF2

PubMed Central

Korobova, Farida; Ramabhadran, Vinay; Higgs, Henry N.

2013-01-01

Mitochondrial fission is fundamentally important to cellular physiology. The dynamin-related protein Drp1 mediates fission, and interaction between mitochondrion and endoplasmic reticulum (ER) enhances fission. However, the mechanism for Drp1 recruitment to mitochondria is unclear, although previous results implicate actin involvement. Here, we found that actin polymerization through ER-localized inverted formin 2 (INF2) was required for efficient mitochondrial fission in mammalian cells. INF2 functioned upstream of Drp1. Actin filaments appeared to accumulate between mitochondria and INF2-enriched ER membranes at constriction sites. Thus, INF2-induced actin filaments may drive initial mitochondrial constriction, which allows Drp1-driven secondary constriction. Because INF2 mutations can lead to Charcot-Marie-Tooth disease, our results provide a potential cellular mechanism for this disease state. PMID:23349293

Quantum transport through MoS2 constrictions defined by photodoping

NASA Astrophysics Data System (ADS)

Epping, Alexander; Banszerus, Luca; Güttinger, Johannes; Krückeberg, Luisa; Watanabe, Kenji; Taniguchi, Takashi; Hassler, Fabian; Beschoten, Bernd; Stampfer, Christoph

2018-05-01

We present a device scheme to explore mesoscopic transport through molybdenum disulfide (MoS2) constrictions using photodoping. The devices are based on van-der-Waals heterostructures where few-layer MoS2 flakes are partially encapsulated by hexagonal boron nitride (hBN) and covered by a few-layer graphene flake to fabricate electrical contacts. Since the as-fabricated devices are insulating at low temperatures, we use photo-induced remote doping in the hBN substrate to create free charge carriers in the MoS2 layer. On top of the device, we place additional metal structures, which define the shape of the constriction and act as shadow masks during photodoping of the underlying MoS2/hBN heterostructure. Low temperature two- and four-terminal transport measurements show evidence of quantum confinement effects.

Combined in vivo and ex vivo analysis of mesh mechanics in a porcine hernia model.

PubMed

Kahan, Lindsey G; Lake, Spencer P; McAllister, Jared M; Tan, Wen Hui; Yu, Jennifer; Thompson, Dominic; Brunt, L Michael; Blatnik, Jeffrey A

2018-02-01

Hernia meshes exhibit variability in mechanical properties, and their mechanical match to tissue has not been comprehensively studied. We used an innovative imaging model of in vivo strain tracking and ex vivo mechanical analysis to assess effects of mesh properties on repaired abdominal walls in a porcine model. We hypothesized that meshes with dissimilar mechanical properties compared to native tissue would alter abdominal wall mechanics more than better-matched meshes. Seven mini-pigs underwent ventral hernia creation and subsequent open repair with one of two heavyweight polypropylene meshes. Following mesh implantation with attached radio-opaque beads, fluoroscopic images were taken at insufflation pressures from 5 to 30 mmHg on postoperative days 0, 7, and 28. At 28 days, animals were euthanized and ex vivo mechanical testing performed on full-thickness samples across repaired abdominal walls. Testing was conducted on 13 mini-pig controls, and on meshes separately. Stiffness and anisotropy (the ratio of stiffness in the transverse versus craniocaudal directions) were assessed. 3D reconstructions of repaired abdominal walls showed stretch patterns. As pressure increased, both meshes expanded, with no differences between groups. Over time, meshes contracted 17.65% (Mesh A) and 0.12% (Mesh B; p = 0.06). Mesh mechanics showed that Mesh A deviated from anisotropic native tissue more than Mesh B. Compared to native tissue, Mesh A was stiffer both transversely and craniocaudally. Explanted repaired abdominal walls of both treatment groups were stiffer than native tissue. Repaired tissue became less anisotropic over time, as mesh properties prevailed over native abdominal wall properties. This technique assessed 3D stretch at the mesh level in vivo in a porcine model. While the abdominal wall expanded, mesh-ingrown areas contracted, potentially indicating stresses at mesh edges. Ex vivo mechanics demonstrate that repaired tissue adopts mesh properties, suggesting that a better-matched mesh could reduce changes to abdominal wall mechanics.

Differentiation between intra-abdominal neoplasms and abscesses in horses, using clinical and laboratory data: 40 cases (1973-1988).

PubMed

Zicker, S C; Wilson, W D; Medearis, I

1990-04-01

The medical records of 25 horses with intra-abdominal neoplasms and 15 horses with intra-abdominal abscesses were reviewed. Common clinical signs of disease observed by owners of horses in both groups included anorexia, weight loss, fever, signs of colic, and depression. Clinical laboratory abnormalities included leukocytosis, hyperfibrinogenemia, hypoalbuminemia, and hypocalcemia. There was considerable overlap of laboratory test results within and between the 2 groups of horses. Peritoneal fluid was classified as an exudate in 12 of 15 horses with intra-abdominal abscesses and in 14 of 25 horses with intra-abdominal neoplasms. Cytologic examination of peritoneal fluid yielded an accurate diagnosis in 11 of 25 horses with neoplasia and in 3 of 15 horses with abscesses. A mean number of 1.45 cytologic analyses/horse was needed to diagnose neoplasms in the 11 horses in which the analysis was successful in definitively diagnosing the condition.

Control of abdominal muscles by brain stem respiratory neurons in the cat

NASA Technical Reports Server (NTRS)

Miller, Alan D.; Ezure, Kazuhisa; Suzuki, Ichiro

1985-01-01

The nature of the control of abdominal muscles by the brain stem respiratory neurons was investigated in decerebrate unanesthetized cats. First, it was determined which of the brain stem respiratory neurons project to the lumbar cord (from which the abdominal muscles receive part of their innervation), by stimulating the neurons monopolarly. In a second part of the study, it was determined if lumbar-projecting respiratory neurons make monosynaptic connections with abdominal motoneurons; in these experiments, discriminate spontaneous spikes of antidromically acivated expiratory (E) neurons were used to trigger activity from both L1 and L2 nerves. A large projection was observed from E neurons in the caudal ventral respiratory group to the contralateral upper lumber cord. However, cross-correlation experiments found only two (out of 47 neuron pairs tested) strong monosynaptic connections between brain stem neurons and abdominal motoneurons.

Investigating the Slow Axonal Transport of Neurofilaments: A Precursor for Optimal Neuronal Signaling

NASA Astrophysics Data System (ADS)

Johnson, Christopher M.

Neurofilaments are the intermediate filaments of neurons and are the most abundant structure of the neuronal cytoskeleton. Once synthesized within the cell body they are then transported throughout the axon along microtubule tracks, driven by the molecular motors kinesin and dynein. This movement is characterized by long pauses with no movement interrupted by infrequent bouts of rapid movement, resulting in an aggregate dense cytoskeletal structure, which serves to regulate an axon's shape and size. Curiously, the modulated kinetics of these polymers produces a very regular, yet non-uniform, morphology in myelinated axons which are composed of discretely spaced myelin-ensheathed segments that are separated by short constricted regions called "nodes of Ranvier". This unique design optimizes the conduction velocity of myelinated axons at minimal fiber size. Hence, neurofilaments regulate the axon caliber to optimize neuron function. The goal of this dissertation is to investigate the motile mechanism of neurofilament transport as well as the resulting electrophysiological effects that follow. We start by examining highly time-resolved kymograph images generated from recorded neurofilament movement via epifluorescence microscopy. Using kymograph analysis, edge detection algorithms, and pixel smoothing tactics, neurofilament trajectories are extracted and used to obtain statistical distributions for the characteristics of how these filaments move within cells. The results suggest that the observed intermittent and bidirectional motions of these filaments might be explained by a model in which dynein and kinesin motors attach to a single neurofilament cargo and interact through mechanical forces only (i.e. a "tug-of-war" model). We test this hypothesis by developing two discrete-state stochastic models for the kinetic cycles of kinesin and dynein, which are then incorporated into a separate stochastic model that represents the posed tug-of-war scenario. We then systematically vary the number of motors in the model and attempt to identify those combinations of motors that show an agreement with the motility characteristic found from the above mentioned kymographs. By pruning the modeled data in accordance with the experimental results, our model can render an estimate of how many motors are attached to the cargo during transport. The model predicts that, on average, the total number of active motors on each neurofilament is relatively small and relatively independent of polymer length, which suggests that the motors may not be distributed uniformly along the filaments. Finally, we develop a model to explore the physiological function of axon morphology sculpted by neurofilament kinetics. Specifically, nodal constrictions are generated by slowing of neurofilaments in the internodal domain (Monsma et al., 2014), but the physiological function of these constrictions is unknown. To address this, we develop a computational model to investigate the effect of nodal constrictions on the axonal conduction velocity. For a fixed number of ion channels, we find that there is an optimal extent of nodal constriction which minimizes the internodal axon caliber that is required to achieve a given target conduction velocity, and we show that this is sensitive to the precise geometry of the axon and myelin sheath in the flanking paranodal regions. Thus axonal constrictions appear to be a biological adaptation that serves to minimize axonal volume, thereby maximizing the spatial and metabolic efficiency of these processes.

Mucus clearance from the pulmonary system by mechanical means: a dual-excitation approach.

PubMed

Ignagni, Mario; O'Dea, Thomas

2013-01-01

A dual-excitation approach to mechanical clearance of mucus from the pulmonary system is described. The approach employs independently controlled vibratory and constrictive pressure stimulations to the thorax. Patient cooperative efforts are integrated into the therapy regimen as a means of enhancing the efficacy of the treatment. An engineering model that demonstrates the capability to generate vibratory and constrictive pressure variations at specified levels is described.

Novel roles for actin in mitochondrial fission

PubMed Central

Hatch, Anna L.; Gurel, Pinar S.; Higgs, Henry N.

2014-01-01

ABSTRACT Mitochondrial dynamics, including fusion, fission and translocation, are crucial to cellular homeostasis, with roles in cellular polarity, stress response and apoptosis. Mitochondrial fission has received particular attention, owing to links with several neurodegenerative diseases. A central player in fission is the cytoplasmic dynamin-related GTPase Drp1, which oligomerizes at the fission site and hydrolyzes GTP to drive membrane ingression. Drp1 recruitment to the outer mitochondrial membrane (OMM) is a key regulatory event, which appears to require a pre-constriction step in which the endoplasmic reticulum (ER) and mitochondrion interact extensively, a process termed ERMD (ER-associated mitochondrial division). It is unclear how ER–mitochondrial contact generates the force required for pre-constriction or why pre-constriction leads to Drp1 recruitment. Recent results, however, show that ERMD might be an actin-based process in mammals that requires the ER-associated formin INF2 upstream of Drp1, and that myosin II and other actin-binding proteins might be involved. In this Commentary, we present a mechanistic model for mitochondrial fission in which actin and myosin contribute in two ways; firstly, by supplying the force for pre-constriction and secondly, by serving as a coincidence detector for Drp1 binding. In addition, we discuss the possibility that multiple fission mechanisms exist in mammals. PMID:25217628

Changes of the eye optics after iris constriction☆

PubMed Central

Montés-Micó, Robert; Hernández, Patricio; Fernández-Sánchez, Vicente; Bonaque, Sergio; Lara, Francisco; López-Gil, Norberto

2011-01-01

Purpose To evaluate the possible change in the optics of the human eye after iris constriction. Methods Ocular aberrations were measured under natural viewing conditions in 26 eyes. The measured eyes fixated on a dim target while the contralateral eye was either occluded (so the measured eye had a large pupil) or highly illuminated (so the measured eye had a small pupil). The measured eyes fixated to a dim target placed 0.5 D beyond the subject’s far point. Zernike values obtained in both situations were compared within the same pupil diameter corresponding to the one obtained under the high illumination condition. Results Significant variation in some aberration coefficients were found between the two illumination conditions. Specially, spherical aberration (SA) increased significantly after pupil miosis (P = .0017). The mean increase of SA measured was 0.018 microns, for a 3-mm pupil. Mean values of other ocular aberrations also vary significantly after pupil miosis (changes were larger than the standard deviation of the repeated measurements). A mean paraxial hyperopic shift of one third of diopter was found after iris constriction. Conclusion Iris constriction slightly modifies the optics of the eye. The small hyperopic shift of the best image plane after iris constriction may be explained by a change in the lens shape and/or position.

Role of calcium in the constriction of isolated cerebral arteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendling, W.W.

1987-01-01

Calcium entry blockers (CEB) have been used in the experimental treatment or prevention of many cerebrovascular disorders including stroke, post-ischemic hypoperfusion after cardiac arrest, cerebral vasospasm after subarachnoid hemorrhage, and migraine headache. However, the mechanism of action of these drugs on the cerebral circulation is poorly understood. This study examined the effects of calcium antagonists, Ca/sup 2 +/-deficient solutions, and vasocostrictors on cerebrovascular tone and /sup 45/Ca fluxes, to determine the role of calcium in cerebral arterial constriction. A Scatchard plot of /sup 45/Ca binding to BMCA showed that Ca/sup 2 +/ was bound at either low or high affinitymore » binding sties. The four vasoconstrictors (potassium, serotonin, PGF/sub 2 ..cap alpha../, or SQ-26,655) each increased low affinity /sup 45/Ca uptake into BMCA. The results demonstrate that: (1) Potassium and serotonin constrict BMCA mainly by promoting Ca/sup 2 +/ influx through CEB-sensitive channels; (2) PGF/sub 2 ..cap alpha../ and SQ-26,655 constrict BMCA in part by promoting Ca/sup 2 +/ influx through CEB-sensitive channels, and in part by releasing Ca/sup 2 +/ from depletable internal stores; (3) The major action of CEB on BMCA is to block vasoconstrictor-induced Ca/sup 2 +/ uptake through both potential-operated (K/sup +/-stimulated) and receptor-operated channels.« less

Emotional Expression and Heart Rate in High-Risk Infants during the Face-To-Face/Still-Face

PubMed Central

Mattson, Whitney I.; Ekas, Naomi V.; Lambert, Brittany; Tronick, Ed; Lester, Barry M.; Messinger, Daniel S.

2013-01-01

In infants, eye constriction—the Duchenne marker—and mouth opening appear to index the intensity of both positive and negative facial expressions. We combined eye constriction and mouth opening that co-occurred with smiles and cry-faces (respectively, the prototypic expressions of infant joy and distress) to measure emotional expression intensity. Expression intensity and heart rate were measured throughout the Face-to-Face/Still Face (FFSF) in a sample of infants with prenatal cocaine exposure who were at risk for developmental difficulties. Smiles declined and cry-faces increased in the still-face episode, but the distribution of eye constriction and mouth opening in smiles and cry-faces did not differ across episodes of the FFSF. As time elapsed in the still face episode potential indices of intensity increased, cry-faces were more likely to be accompanied by eye constriction and mouth opening. During cry-faces there were also moderately stable individual differences in the quantity of eye constriction and mouth opening. Infant heart rate was higher during cry-faces and lower during smiles, but did not vary with intensity of expression or by episode. In sum, infants express more intense negative affect as the still-face progresses, but do not show clear differences in expressive intensity between episodes of the FFSF. PMID:24095807

Measurements and simulation of liquid films during drainage displacements and snap-off in constricted capillary tubes.

PubMed

Roman, Sophie; Abu-Al-Saud, Moataz O; Tokunaga, Tetsu; Wan, Jiamin; Kovscek, Anthony R; Tchelepi, Hamdi A

2017-12-01

When a wetting liquid is displaced by air in a capillary tube, a wetting film develops between the tube wall and the air that is responsible for the snap-off mechanism of the gas phase. By dissolving a dye in the wetting phase it is possible to relate a measure of the absorbance in the capillary to the thickness of liquid films. These data could be used to compare with cutting edge numerical simulations of the dynamics of snap-off for which experimental and numerical data are lacking. Drainage experiments in constricted capillary tubes were performed where a dyed wetting liquid is displaced by air for varying flow rates. We developed an optical method to measure liquid film thicknesses that range from 3 to 1000μm. The optical measures are validated by comparison with both theory and direct numerical simulations. In a constricted capillary tube we observed, both experimentally and numerically, a phenomenon of snap-off coalescence events in the vicinity of the constriction that bring new insights into our understanding and modeling of two-phase flows. In addition, the good agreement between experiments and numerical simulations gives confidence to use the numerical method for more complex geometries in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

Cluster-guided imaging-based CFD analysis of airflow and particle deposition in asthmatic human lungs

NASA Astrophysics Data System (ADS)

Choi, Jiwoong; Leblanc, Lawrence; Choi, Sanghun; Haghighi, Babak; Hoffman, Eric; Lin, Ching-Long

2017-11-01

The goal of this study is to assess inter-subject variability in delivery of orally inhaled drug products to small airways in asthmatic lungs. A recent multiscale imaging-based cluster analysis (MICA) of computed tomography (CT) lung images in an asthmatic cohort identified four clusters with statistically distinct structural and functional phenotypes associating with unique clinical biomarkers. Thus, we aimed to address inter-subject variability via inter-cluster variability. We selected a representative subject from each of the 4 asthma clusters as well as 1 male and 1 female healthy controls, and performed computational fluid and particle simulations on CT-based airway models of these subjects. The results from one severe and one non-severe asthmatic cluster subjects characterized by segmental airway constriction had increased particle deposition efficiency, as compared with the other two cluster subjects (one non-severe and one severe asthmatics) without airway constriction. Constriction-induced jets impinging on distal bifurcations led to excessive particle deposition. The results emphasize the impact of airway constriction on regional particle deposition rather than disease severity, demonstrating the potential of using cluster membership to tailor drug delivery. NIH Grants U01HL114494 and S10-RR022421, and FDA Grant U01FD005837. XSEDE.

Sexual Dimorphism and Mating Behavior in Anomala testaceipennis

PubMed Central

Rodrigues, Sérgio Roberto; Gomes, Elias Soares; Bento, José Maurício Simões

2014-01-01

Abstract The beetle, Anomala testaceipennis Blanchard (Coleoptera: Scarabaeidae), occurs in central-western Brazil where larvae feed on the roots of plants causing damage. This research aimed to study sexual dimorphism and mating behavior of A. testaceipennis . Adults of A. testaceipennis were collected with light traps in the experimental area of the State University of Mato Grosso do Sul, in Aquidauana. Laboratory experiments were performed to describe copulation behavior and adult morphology of males and females. In males the last abdominal segment has a pronounced constriction, which is absent in females, and the male’s last segment of the first pair of legs has a ventral projection, which is poorly developed in females. The mating activities of adults begin soon after sunset, when adults leave the soil and fly. When the male encounters a female, he touches her with antennae and tarsi. If accepted, the male climbs on the female and remains on her back, and soon after the copulation begins. When the female does not accept the male for mating, she moves rapidly and can roll on the ground, and by so removing the male. In the field, adults feed and mate on bloomed trees of Oiti, Licania tomentosa Benth (Malpighiales: Chrysobalanaceae) and Louro, Cordia glabrata Martius (Boraginaceae). In trees without inflorescences no adults of this species were found. PMID:25502043

Pharmacological Evaluation and Preparation of Nonsteroidal Anti-Inflammatory Drugs Containing an N-Acyl Hydrazone Subunit

PubMed Central

de Melo, Thais Regina Ferreira; Chelucci, Rafael Consolin; Pires, Maria Elisa Lopes; Dutra, Luiz Antonio; Barbieri, Karina Pereira; Bosquesi, Priscila Longhin; Trossini, Gustavo Henrique Goulart; Chung, Man Chin; dos Santos, Jean Leandro

2014-01-01

A series of anti-inflammatory derivatives containing an N-acyl hydrazone subunit (4a–e) were synthesized and characterized. Docking studies were performed that suggest that compounds 4a–e bind to cyclooxygenase (COX)-1 and COX-2 isoforms, but with higher affinity for COX-2. The compounds display similar anti-inflammatory activities in vivo, although compound 4c is the most effective compound for inhibiting rat paw edema, with a reduction in the extent of inflammation of 35.9% and 52.8% at 2 and 4 h, respectively. The anti-inflammatory activity of N-acyl hydrazone derivatives was inferior to their respective parent drugs, except for compound 4c after 5 h. Ulcerogenic studies revealed that compounds 4a–e are less gastrotoxic than the respective parent drug. Compounds 4b–e demonstrated mucosal damage comparable to celecoxib. The in vivo analgesic activities of the compounds are higher than the respective parent drug for compounds 4a–b and 4d–e. Compound 4a was more active than dipyrone in reducing acetic-acid-induced abdominal constrictions. Our results indicate that compounds 4a–e are anti-inflammatory and analgesic compounds with reduced gastrotoxicity compared to their respective parent non-steroidal anti-inflammatory drugs. PMID:24714090

Cardiac Protection of Valsartan on Juvenile Rats with Heart Failure by Inhibiting Activity of CaMKII via Attenuating Phosphorylation.

PubMed

Wu, Yao; Si, Feifei; Ji, Xiaojuan; Jiang, Kunfeng; Song, Sijie; Yi, Qijian

2017-01-01

Background . This study was undertaken to determine relative contributions of phosphorylation and oxidation to the increased activity of calcium/calmodulin-stimulated protein kinase II (CaMKII) in juveniles with cardiac myocyte dysfunction due to increased pressure overload. Methods . Juvenile rats underwent abdominal aortic constriction to induce heart failure. Four weeks after surgery, rats were then randomly divided into two groups: one group given valsartan (HF + Val) and the other group given placebo (HF + PBO). Simultaneously, the sham-operated rats were randomly given valsartan (Sham + Val) or placebo (Sham + PBO). After 4 weeks of treatment, Western blot analysis was employed to quantify CaMKII and relative calcium handling proteins (RyR2 and PLN) in all groups. Results . The deteriorated cardiac function was reversed by valsartan treatment. In ventricular muscle cells of group HF + PBO, Thr287 phosphorylation of CaMKII and S2808 phosphorylation of RyR2 and PLN were increased and S16 phosphorylation of PLN was decreased compared to the other groups, while Met281 oxidation was not significantly elevated. In addition, these changes in the expression of calcium handling proteins were ameliorated by valsartan administration. Conclusions . The phosphorylation of Thr286 is associated with the early activation of CaMKII rather than the oxidation of Met281.

Cathepsin K Knockout Alleviates Pressure Overload–Induced Cardiac Hypertrophy

PubMed Central

Hua, Yinan; Xu, Xihui; Shi, Guo-Ping; Chicco, Adam J.; Ren, Jun; Nair, Sreejayan

2014-01-01

Evidence from human and animal studies has documented elevated levels of lysosomal cysteine protease cathepsin K in failing hearts. Here, we hypothesized that ablation of cathepsin K mitigates pressure overload–induced cardiac hypertrophy. Cathepsin K knockout mice and their wild-type littermates were subjected to abdominal aortic constriction, resulting in cardiac remodeling (heart weight, cardiomyocyte size, left ventricular wall thickness, and end diastolic and end systolic dimensions) and decreased fractional shortening, the effects of which were significantly attenuated or ablated by cathepsin K knockout. Pressure overload dampened cardiomyocyte contractile function along with decreased resting Ca2+ levels and delayed Ca2+ clearance, which were partly resolved by cathepsin K knockout. Cardiac mammalian target of rapamycin and extracellular signal-regulated kinases (ERK) signaling cascades were upregulated by pressure overload, the effects of which were attenuated by cathepsin K knockout. In cultured H9c2 myoblast cells, silencing of cathepsin K blunted, whereas cathepsin K transfection mimicked phenylephrine–induced hypertrophic response, along with elevated phosphorylation of mammalian target of rapamycin and ERK. In addition, cathepsin K protein levels were markedly elevated in human hearts of end-stage dilated cardiomyopathy. Collectively, our data suggest that cathepsin K ablation mitigates pressure overload–induced hypertrophy, possibly via inhibition of the mammalian target of rapamycin and ERK pathways. PMID:23529168

Impact of obesity on hypertension-induced cardiac remodeling: role of oxidative stress and its modulation by gemfibrozil treatment in rats.

PubMed

Singh, Randhir; Singh, Amrit Pal; Singh, Manjeet; Krishan, Pawan

2011-01-15

This study investigated the possible synergistic role of obesity in hypertension-induced cardiac remodeling and its modulation by gemfibrozil treatment in rats. Male Wistar rats were fed a high-fat diet (HFD) for 90 days. Normal rats were subjected to hypertension by partial abdominal aortic constriction (PAAC) for 28 days. In the HFD+PAAC control group, rats on HFD were subjected to PAAC on the 62nd day and were sacrificed on the 90th day. HFD and PAAC individually resulted in significant cardiac hypertrophy and fibrosis along with increased oxidative stress and mean arterial blood pressure (MABP) in rats as evidenced by various morphological, biochemical, and histological parameters. Moreover, the HFD + PAAC control group showed marked cardiac remodeling compared to rats subjected to HFD or PAAC alone. The HFD+gemfibrozil and HFD+PAAC+gemfibrozil groups showed significant reduction in cardiac remodeling along with reduction in oxidative stress and MABP. Hence, it may be concluded that oxidative stress plays a key role in obesity-mediated synergistic effects on induction and progression of PAAC-induced cardiac remodeling, and its deleterious effects could be reversed by gemfibrozil treatment in rats through its antioxidant activity. Copyright © 2010 Elsevier Inc. All rights reserved.

Educational inequality in the occurrence of abdominal obesity: Pró-Saúde Study

PubMed Central

Alves, Ronaldo Fernandes Santos; Faerstein, Eduardo

2015-01-01

OBJECTIVE To estimate the degree of educational inequality in the occurrence of abdominal obesity in a population of non-faculty civil servants at university campi. METHODS In this cross-sectional study, we used data from 3,117 subjects of both genders aged 24 to 65-years old, regarding the baseline of Pró-Saúde Study, 1999-2001. Abdominal obesity was defined according to abdominal circumference thresholds of 88 cm for women and 102 cm for men. A multi-dimensional, self-administered questionnaire was used to evaluate education levels and demographic variables. Slope and relative indices of inequality, and Chi-squared test for linear trend were used in the data analysis. All analyses were stratified by genders, and the indices of inequality were standardized by age. RESULTS Abdominal obesity was the most prevalent among women (43.5%; 95%CI 41.2;45.9), as compared to men (24.3%; 95%CI 22.1;26.7), in all educational strata and age ranges. The association between education levels and abdominal obesity was an inverse one among women (p < 0.001); it was not statistically significant among men (p = 0.436). The educational inequality regarding abdominal obesity in the female population, in absolute terms (slope index of inequality), was 24.0% (95%CI 15.5;32.6). In relative terms (relative index of inequality), it was 2.8 (95%CI 1.9;4.1), after the age adjustment. CONCLUSIONS Gender inequality in the prevalence of abdominal obesity increases with older age and lower education. The slope and relative indices of inequality summarize the strictly monotonous trend between education levels and abdominal obesity, and it described educational inequality regarding abdominal obesity among women. Such indices provide relevant quantitative estimates for monitoring abdominal obesity and dealing with health inequalities. PMID:26465669

Long Duration Hot Hydrogen Exposure of Nuclear Thermal Rocket Materials

NASA Technical Reports Server (NTRS)

Litchford, Ron J.; Foote, John P.; Hickman, Robert; Dobson, Chris; Clifton, Scooter

2007-01-01

An arc-heater driven hyper-thermal convective environments simulator was recently developed and commissioned for long duration hot hydrogen exposure of nuclear thermal rocket materials. This newly established non-nuclear testing capability uses a high-power, multi-gas, wall-stabilized constricted arc-heater to .produce high-temperature pressurized hydrogen flows representative of nuclear reactor core environments, excepting radiation effects, and is intended to serve as a low cost test facility for the purpose of investigating and characterizing candidate fuel/structural materials and improving associated processing/fabrication techniques. Design and engineering development efforts are fully summarized, and facility operating characteristics are reported as determined from a series of baseline performance mapping runs and long duration capability demonstration tests.

Chronic Abdominal Wall Pain.

PubMed

Koop, Herbert; Koprdova, Simona; Schürmann, Christine

2016-01-29

Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

[Abdominal Tuberculosis in children and adolescents. A diagnostic challenge].

PubMed

Reto Valiente, Luz; Pichilingue Reto, Catherina; Pichilingue Prieto, Oscar; Dolores Cerna, Ketty

2015-01-01

To present our experience with abdominal tuberculosis in children and adolescents treated in our hospital from 2003 - 2014. It is a retrospective study. We have collected clinical records of inpatients <20 years old who were admitted at Hipolito Unanue Hospital from January 2003 to July 2014, with diagnosis of abdominal tuberculosis. Among the overall 30 patients, 16 (53.33%) were female and 14 (46.67%) were male. The mean age of all patients was 16.5 years. The most common clinical features were abdominal pain in 29 (96.67%), fever in 26 (86.67%), ascites in 23 (76.67%) and loss of weight in 21 (70%). 63.33% of the patients were eutrophics, 13.34% were overweight or obese and only 23.33% suffered of malnutrition. TB contact was present in 10 (33.33%). Positive tuberculin skin tests were seen in 10%. Extra-abdominal tuberculosis was found in 22 patients (63.32%). 12 cases had coexisting pulmonary tuberculosis and 4 cases had pleural effusion. 12 patients (40%) had tuberculous peritonitis; 12 patients (40%) had intestinal tuberculosis and peritoneal tuberculosis and 4 patients (13.33%) had intestinal tuberculosis. Bacteriological confirmation of tuberculosis was achieved in 10 cases (33.33%). Antituberculous therapy for 6 months was effective in 29 cases. One patient died who multifocal tuberculosis with HIV had associated. Abdominal tuberculosis is seen in 4.37% of children affected with tuberculosis, of which over 63% will have extra abdominal manifestations. Abdominal tuberculosis should be considered in patients with abdominal pain, fever, weight loss and abnormal chest radiography. Imaging can be useful for early diagnosis of abdominal tuberculosis.

Laparoscopic bridging vs. anatomic open reconstruction for midline abdominal hernia mesh repair [LABOR]: single-blinded, multicenter, randomized, controlled trial on long-term functional results.

PubMed

Stabilini, Cesare; Bracale, Umberto; Pignata, Giusto; Frascio, Marco; Casaccia, Marco; Pelosi, Paolo; Signori, Alessio; Testa, Tommaso; Rosa, Gian Marco; Morelli, Nicola; Fornaro, Rosario; Palombo, Denise; Perotti, Serena; Bruno, Maria Santina; Imperatore, Mikaela; Righetti, Carolina; Pezzato, Stefano; Lazzara, Fabrizio; Gianetta, Ezio

2013-10-28

Re-approximation of the rectal muscles along the midline is recommended by some groups as a rule for incisional and ventral hernia repairs. The introduction of laparoscopic repair has generated a debate because it is not aimed at restoring abdominal wall integrity but instead aims just to bridge the defect. Whether restoration of the abdominal integrity has a real impact on patient mobility is questionable, and the available literature provides no definitive answer. The present study aims to compare the functional results of laparoscopic bridging with those of re-approximation of the rectal muscle in the midline as a mesh repair for ventral and incisional abdominal defect through an "open" access. We hypothesized that, for the type of defect suitable for a laparoscopic bridging, the effect of an anatomical reconstruction is near negligible, thus not a fixed rule. The LABOR trial is a multicenter, prospective, two-arm, single-blinded, randomized trial. Patients of more than 60 years of age with a defect of less than 10 cm at its greatest diameter will be randomly submitted to open Rives or laparoscopic defect repair. All the participating patients will have a preoperative evaluation of their abdominal wall strength and mobility along with volumetry, respiratory function test, intraabdominal pressure and quality of life assessment.The primary outcome will be the difference in abdominal wall strength as measured by a double leg-lowering test performed at 12 months postoperatively. The secondary outcomes will be the rate of recurrence and changes in baseline abdominal mobility, respiratory function tests, intraabdominal pressure, CT volumetry and quality of life at 6 and 12 months postoperatively. The study will help to define the most suitable treatment for small-medium incisional and primary hernias in patients older than 60 years. Given a similar mid-term recurrence rate in both groups, if the trial shows no differences among treatments (acceptance of the null-hypothesis), then the choice of whether to submit a patient to one intervention will be made on the basis of cost and the surgeon's experience. Current Controlled Trials ISRCTN93729016.

Depression-like behavior and mechanical allodynia are reduced by bis selenide treatment in mice with chronic constriction injury: a comparison with fluoxetine, amitriptyline, and bupropion.

PubMed

Jesse, Cristiano R; Wilhelm, Ethel A; Nogueira, Cristina W

2010-12-01

Neuropathic pain is associated with significant co-morbidities, including depression, which impact considerably on the overall patient experience. Pain co-morbidity symptoms are rarely assessed in animal models of neuropathic pain. Neuropathic pain is characterized by hyperexcitability within nociceptive pathways and remains difficult to treat with standard analgesics. The present study determined the effect of bis selenide and conventional antidepressants (fluoxetine, amitriptyline, and bupropion) on neuropathic pain using mechanical allodynic and on depressive-like behavior. Male mice were subjected to chronic constriction injury (CCI) or sham surgery and were assessed on day 14 after operation. Mice received oral treatment with bis selenide (1-5 mg/kg), fluoxetine, amitriptyline, or bupropion (10-30 mg/kg). The response frequency to mechanical allodynia in mice was measured with von Frey hairs. Mice were evaluated in the forced swimming test (FST) test for depression-like behavior. The CCI procedure produced mechanical allodynia and increased depressive-like behavior in the FST. All of the drugs produced antiallodynic effects in CCI mice and produced antidepressant effects in control mice without altering locomotor activity. In CCI animals, however, only the amitriptyline and bis selenide treatments significantly reduced immobility in the FST. These data demonstrate an important dissociation between the antiallodynic and antidepressant effects in mice when tested in a model of neuropathic pain. Depressive behavior in CCI mice was reversed by bis selenide and amitriptyline but not by the conventional antidepressants fluoxetine and buproprion. Bis selenide was more potent than the other drugs tested for antidepressant-like and antiallodynic effects in mice.

Consensus Statement of Society of Abdominal Radiology Disease-Focused Panel on Barium Esophagography in Gastroesophageal Reflux Disease.

PubMed

Levine, Marc S; Carucci, Laura R; DiSantis, David J; Einstein, David M; Hawn, Mary T; Martin-Harris, Bonnie; Katzka, David A; Morgan, Desiree E; Rubesin, Stephen E; Scholz, Francis J; Turner, Mary Ann; Wolf, Ellen L; Canon, Cheri L

2016-11-01

The Society of Abdominal Radiology established a panel to prepare a consensus statement on the role of barium esophagography in gastroesophageal reflux disease (GERD), as well as recommended techniques for performing the fluoroscopic examination and the gamut of findings associated with this condition. Because it is an inexpensive, noninvasive, and widely available study that requires no sedation, barium esophagography may be performed as the initial test for GERD or in conjunction with other tests such as endoscopy.

Pupillary Responses to Full-Field Chromatic Stimuli Are Reduced in Patients with Early-Stage Primary Open-Angle Glaucoma.

PubMed

Najjar, Raymond P; Sharma, Sourabh; Atalay, Eray; Rukmini, Annadata V; Sun, Christopher; Lock, Jing Zhan; Baskaran, Mani; Perera, Shamira A; Husain, Rahat; Lamoureux, Ecosse; Gooley, Joshua J; Aung, Tin; Milea, Dan

2018-03-21

To evaluate the ability of chromatic pupillometry to reveal abnormal pupillary responses to light in patients with early-stage primary open-angle glaucoma (POAG) and to test whether the degree of pupillometric impairment correlates with structural hallmarks of optic nerve damage in the disease. Cross-sectional study. Forty-six patients with early-stage POAG (63.4±8.3 years, 63% male, 87% ethnic-Chinese) and 90 age-matched healthy controls (61.4±8.6 years, 34% male, 89% ethnic-Chinese). Patients with POAG had a visual field mean deviation (VFMD) of -6 decibels or better on automated perimetry. Each participant underwent a monocular 2-minute exposure to blue light (462 nm) followed by another 2-minute exposure to red light (638 nm) using a modified Ganzfeld dome equipped with a light-emitting diode lighting system. The light stimuli intensity was increased logarithmically to evaluate the combined extrinsic and intrinsic response of intrinsically photosensitive retinal ganglion cells (ipRGCs). Light-induced changes in horizontal pupil diameter were assessed monocularly using infrared pupillography. Baseline-adjusted, light-induced pupillary constriction amplitudes were calculated, and individual irradiance-response curves were constructed for each stimulus. Pupillary constriction amplitudes were compared between groups and across light intensities using a linear mixed model analysis. The linear relationship between pupillometric parameters and different structural and functional features of glaucoma was assessed using Pearson's correlation analysis. Light-induced pupillary constriction was reduced in patients with early-stage POAG compared with controls at moderate to high irradiances (≥11 Log photons/cm 2 /s) of blue (P = 0.003) and red (P < 0.001) light. Maximal pupillary constriction amplitude was correlated with retinal nerve fiber layer thickness (RNFL) thickness (blue: r = 0.51, P < 0.001; red: r = 0.45, P = 0.002) in patients with POAG but not in controls. Conversely, pupillometric parameters were not correlated with visual field scores in patients with early-stage POAG. Patients with early-stage POAG exhibit reduced pupillary responses to moderate and high irradiances of blue and red lights. This wavelength-independent functional alteration correlates with structural thinning of the RNFL and could be the consequence of dysfunction or loss of melanopsin expressing ipRGCs in the early stages of the disease. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Augmented endothelial l-arginine transport ameliorates pressure-overload-induced cardiac hypertrophy.

PubMed

Rajapakse, Niwanthi W; Johnston, Tamara; Kiriazis, Helen; Chin-Dusting, Jaye P; Du, Xiao-Jun; Kaye, David M

2015-07-01

What is the central question of this study? What is the potential role of endothelial NO production via overexpression of the l-arginine transporter, CAT1, as a mitigator of cardiac hypertrophy? What is the main finding and its importance? Augmentation of endothelium-specific l-arginine transport via CAT1 can attenuate pressure-overload-dependent cardiac hypertrophy and fibrosis. Our findings support the conclusion that interventions that improve endothelial l-arginine transport may provide therapeutic utility in the setting of myocardial hypertrophy. Such modifications may be introduced by exercise training or locally delivered gene therapy, but further experimental and clinical studies are required. Endothelial dysfunction has been postulated to play a central role in the development of cardiac hypertrophy, probably as a result of reduced NO bioavailability. We tested the hypothesis that increased endothelial NO production, mediated by increased l-arginine transport, could attenuate pressure-overload-induced cardiac hypertrophy. Echocardiography and blood pressure measurements were performed 15 weeks after transverse aortic constriction (TAC) in wild-type (WT) mice (n = 12) and in mice with endothelium-specific overexpression of the l-arginine transporter, CAT1 (CAT+; n = 12). Transverse aortic constriction induced greater increases in heart weight to body weight ratio in WT (by 47%) than CAT+ mice (by 25%) compared with the respective controls (P ≤ 0.05). Likewise, the increase in left ventricular wall thickness induced by TAC was significantly attenuated in CAT+ mice (P = 0.05). Cardiac collagen type I mRNA expression was greater in WT mice with TAC (by 22%; P = 0.03), but not in CAT+ mice with TAC, compared with the respective controls. Transverse aortic constriction also induced lesser increases in β-myosin heavy chain mRNA expression in CAT+ mice compared with WT (P ≤ 0.05). Left ventricular systolic pressure after TAC was 36 and 39% greater in WT and CAT+ mice, respectively, compared with the respective controls (P ≤ 0.001). Transverse aortic constriction had little effect on left ventricular end-diastolic pressure in both genotypes. Taken together, these data indicate that augmenting endothelial function by overexpression of l-arginine transport can attenuate pressure-overload-induced cardiac hypertrophy. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

Abdominal compartment syndrome and ruptured aortic aneurysm: Validation of a predictive test (SCA-AAR).

PubMed

Leclerc, Betty; Salomon Du Mont, Lucie; Parmentier, Anne-Laure; Besch, Guillaume; Rinckenbach, Simon

2018-06-01

The abdominal compartment syndrome (ACS) has been clearly identified as being one of the main causes of mortality after ruptured abdominal aortic aneurysm (rAAA). The ACS is defined as a sustained intra-abdominal pressure > 20 mm Hg associated with a new organ dysfunction or failure. A pilot study was conducted and found that the threshold of 3 among 8 selected criteria, we would predict an ACS occurrence with a 54% positive predictive value and a 92% negative predictive value. But a multicentric prospective study was clearly needed to confirm these results. The outcome of this new study is to assess the qualities of a predictive test on occurrence of the ACS after rAAA surgery. This is a 30 months prospective cohort study conducted in 12 centers and 165 patients will be included. All patients with a rAAA will be consecutively included, whatever the surgical treatment. At the end of surgery, all patients have an abdominal closure and a monitoring of intrabladder pressure will be established every 3 to 4 hours. Decompressive laparotomy will be indicated when ACS occurs. Follow-up period is 1 month. Eight pre- and per-operative criteria will be studied: anemia, hypotension, cardiac arrest, obesity, massive fluid resuscitation, transfusion, hypothermia, and acidosis. In the literature, there is no recommendation about prophylactic decompression, but early decompressive laparotomy appears to improve survival. This study should make it possible to establish a predictive test, detect the ACS early, and consider a prophylactic decompression in the operating room. ClinicalTrials.gov, NCT02859662, Registered on 4 August 2016.

Comparison of Flow and Volume Incentive Spirometry on Pulmonary Function and Exercise Tolerance in Open Abdominal Surgery: A Randomized Clinical Trial.

PubMed

Kumar, Amaravadi Sampath; Alaparthi, Gopala Krishna; Augustine, Alfred Joseph; Pazhyaottayil, Zulfeequer Chundaanveetil; Ramakrishna, Anand; Krishnakumar, Shyam Krishnan

2016-01-01

Surgical procedures in abdominal area lead to changes in pulmonary function, respiratory mechanics and impaired physical capacity leading to postoperative pulmonary complications, which can affect up to 80% of upper abdominal surgery. To evaluate the effects of flow and volume incentive spirometry on pulmonary function and exercise tolerance in patients undergoing open abdominal surgery. A randomized clinical trial was conducted in a hospital of Mangalore city in Southern India. Thirty-seven males and thirteen females who were undergoing abdominal surgeries were included and allocated into flow and volume incentive spirometry groups by block randomization. All subjects underwent evaluations of pulmonary function with measurement of Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), Peak Expiratory Flow (PEF). Preoperative and postoperative measurements were taken up to day 5 for both groups. Exercise tolerance measured by Six- Minute Walk Test during preoperative period and measured again at the time of discharge for both groups. Pulmonary function was analysed by post-hoc analysis and carried out using Bonferroni's 't'-test. Exercise tolerance was analysed by Paired 'T'-test. Pulmonary function (FVC, FEV1, and PEFR) was found to be significantly decreased in 1(st), 2(nd) and 3(rd) postoperative day when compared with preoperative day. On 4(th) and 5(th) postoperative day the pulmonary function (FVC, FEV1, and PEFR) was found to be better preserved in both flow and volume incentive spirometry groups. The Six-Minute Walk Test showed a statistically significant improvement in pulmonary function on the day of discharge than in the preoperative period. In terms of distance covered, the volume- incentive spirometry group showed a greater statistically significant improvement from the preoperative period to the time of discharge than was exhibited by the flow incentive spirometry group. Flow and volume incentive spirometry can be safely recommended to patients undergoing open abdominal surgery as there have been no adverse events recorded. Also, these led to a demonstrable improvement in pulmonary function and exercise tolerance.

Comparison of Flow and Volume Incentive Spirometry on Pulmonary Function and Exercise Tolerance in Open Abdominal Surgery: A Randomized Clinical Trial

PubMed Central

Kumar, Amaravadi Sampath; Augustine, Alfred Joseph; Pazhyaottayil, Zulfeequer Chundaanveetil; Ramakrishna, Anand; Krishnakumar, Shyam Krishnan

2016-01-01

Introduction Surgical procedures in abdominal area lead to changes in pulmonary function, respiratory mechanics and impaired physical capacity leading to postoperative pulmonary complications, which can affect up to 80% of upper abdominal surgery. Aim To evaluate the effects of flow and volume incentive spirometry on pulmonary function and exercise tolerance in patients undergoing open abdominal surgery. Materials and Methods A randomized clinical trial was conducted in a hospital of Mangalore city in Southern India. Thirty-seven males and thirteen females who were undergoing abdominal surgeries were included and allocated into flow and volume incentive spirometry groups by block randomization. All subjects underwent evaluations of pulmonary function with measurement of Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), Peak Expiratory Flow (PEF). Preoperative and postoperative measurements were taken up to day 5 for both groups. Exercise tolerance measured by Six- Minute Walk Test during preoperative period and measured again at the time of discharge for both groups. Pulmonary function was analysed by post-hoc analysis and carried out using Bonferroni’s ‘t’-test. Exercise tolerance was analysed by Paired ‘T’-test. Results Pulmonary function (FVC, FEV1, and PEFR) was found to be significantly decreased in 1st, 2nd and 3rd postoperative day when compared with preoperative day. On 4th and 5th postoperative day the pulmonary function (FVC, FEV1, and PEFR) was found to be better preserved in both flow and volume incentive spirometry groups. The Six-Minute Walk Test showed a statistically significant improvement in pulmonary function on the day of discharge than in the preoperative period. In terms of distance covered, the volume- incentive spirometry group showed a greater statistically significant improvement from the preoperative period to the time of discharge than was exhibited by the flow incentive spirometry group. Conclusion Flow and volume incentive spirometry can be safely recommended to patients undergoing open abdominal surgery as there have been no adverse events recorded. Also, these led to a demonstrable improvement in pulmonary function and exercise tolerance. PMID:26894090

Clogging in constricted suspension flows

NASA Astrophysics Data System (ADS)

Marin, Alvaro; Lhuissier, Henri; Rossi, Massimiliano; Kähler, Christian J.

2018-02-01

The flow of a charged-stabilized suspension through a single constricted channel is studied experimentally by tracking the particles individually. Surprisingly, the behavior is found to be qualitatively similar to that of inertial dry granular systems: For small values of the neck-to-particle size ratio (D /d <3 ), clogs form randomly as arches of the particle span the constriction. The statistics of the clogging events are Poissonian as reported for granular systems and agree for moderate particle volume fraction (ϕ ≈20 % ) with a simple stochastic model for the number of particles at the neck. For larger neck sizes (D /d >3 ), even at the largest ϕ (≈60 %) achievable in the experiments, an uninterrupted particle flow is observed, which resembles that of an hourglass. This particularly small value of D /d (≃3 ) at the transition to a practically uninterrupted flow is attributed to the low effective friction between the particles, achieved by the particle's functionalization and lubrication.

Quantifying parenchymal tethering in a finite element simulation of a human lung slice under bronchoconstriction.

PubMed

Breen, Barbara J; Donovan, Graham M; Sneyd, James; Tawhai, Merryn H

2012-08-15

Airway hyper-responsiveness (AHR), a hallmark of asthma, is a highly complex phenomenon characterised by multiple processes manifesting over a large range of length and time scales. Multiscale computational models have been derived to embody the experimental understanding of AHR. While current models differ in their derivation, a common assumption is that the increase in parenchymal tethering pressure P(teth) during airway constriction can be described using the model proposed by Lai-Fook (1979), which is based on intact lung experimental data for elastic moduli over a range of inflation pressures. Here we reexamine this relationship for consistency with a nonlinear elastic material law that has been parameterised to the pressure-volume behaviour of the intact lung. We show that the nonlinear law and Lai-Fook's relationship are consistent for small constrictions, but diverge when the constriction becomes large. Copyright © 2012 Elsevier B.V. All rights reserved.

Vertical Skin Paddle Orientation for the Latissimus Dorsi Flap in Breast Reconstruction: A Modification to Simultaneously Correct Inferior Pole Constriction and Improve Projection.

PubMed

Fracol, Megan; Grim, Michelle; Lanier, Steven T; Fine, Neil A

2018-03-01

The latissimus dorsi myocutaneous flap is a reliable and frequently used option to bring vascularized skin and soft tissue to improve the stability and aesthetic result in breast reconstruction. Standard techniques with skin paddle inset in a horizontal or oblique fashion preferentially improve anterior projection (when inset at the mastectomy scar) or lower pole and inframammary fold constriction (when inset into the inframammary fold). Here, the authors describe a modification for inset of the latissimus dorsi myocutaneous flap that improves both anterior projection and lower pole/inframammary fold constriction, and also allows the latissimus muscle to fan out and provide complete implant coverage. The vertical inset modification brings new skin and soft tissue into both the inferior pole and the central mastectomy scar, allowing simultaneous improvement in both areas and full use of the latissimus muscle to cover the implant or expander. Therapeutic, IV.

Clogging Transition of Vibration-Driven Vehicles Passing through Constrictions.

PubMed

Patterson, G A; Fierens, P I; Sangiuliano Jimka, F; König, P G; Garcimartín, A; Zuriguel, I; Pugnaloni, L A; Parisi, D R

2017-12-15

We report experimental results on the competitive passage of elongated self-propelled vehicles rushing through a constriction. For the chosen experimental conditions, we observe the emergence of intermittencies similar to those reported previously for active matter passing through narrow doors. Noteworthy, we find that, when the number of individuals crowding in front of the bottleneck increases, there is a transition from an unclogged to a clogged state characterized by a lack of convergence of the mean clog duration as the measuring time increases. It is demonstrated that this transition-which was reported previously only for externally vibrated systems such as colloids or granulars-appears also for self-propelled agents. This suggests that the transition should also occur for the flow through constrictions of living agents (e.g., humans and sheep), an issue that has been elusive so far in experiments due to safety risks.

Clogging Transition of Vibration-Driven Vehicles Passing through Constrictions

NASA Astrophysics Data System (ADS)

Patterson, G. A.; Fierens, P. I.; Sangiuliano Jimka, F.; König, P. G.; Garcimartín, A.; Zuriguel, I.; Pugnaloni, L. A.; Parisi, D. R.

2017-12-01

We report experimental results on the competitive passage of elongated self-propelled vehicles rushing through a constriction. For the chosen experimental conditions, we observe the emergence of intermittencies similar to those reported previously for active matter passing through narrow doors. Noteworthy, we find that, when the number of individuals crowding in front of the bottleneck increases, there is a transition from an unclogged to a clogged state characterized by a lack of convergence of the mean clog duration as the measuring time increases. It is demonstrated that this transition—which was reported previously only for externally vibrated systems such as colloids or granulars—appears also for self-propelled agents. This suggests that the transition should also occur for the flow through constrictions of living agents (e.g., humans and sheep), an issue that has been elusive so far in experiments due to safety risks.

Diagnostic testing for celiac disease among patients with abdominal symptoms: a systematic review.

PubMed

van der Windt, Daniëlle A W M; Jellema, Petra; Mulder, Chris J; Kneepkens, C M Frank; van der Horst, Henriëtte E

2010-05-05

The symptoms and consequences of celiac disease usually resolve with a lifelong gluten-free diet. However, clinical presentation is variable and most patients presenting with abdominal symptoms in primary care will not have celiac disease and unnecessary diagnostic testing should be avoided. To summarize evidence on the performance of diagnostic tests for identifying celiac disease in adults presenting with abdominal symptoms in primary care or similar settings. A literature search via MEDLINE (beginning in January 1966) and EMBASE (beginning in January 1947) through December 2009 and a manual search of references for additional relevant studies. Diagnostic studies were selected if they had a cohort or nested case-control design, enrolled adults presenting with nonacute abdominal symptoms, the prevalence of celiac disease was 15% or less, and the tests used included gastrointestinal symptoms or serum antibody tests. Quality assessment using the Quality Assessment of Diagnostic Accuracy Studies tool and data extraction were performed by 2 reviewers independently. Sensitivities and specificities were calculated for each study and pooled estimates were computed using bivariate analysis if there was clinical and statistical homogeneity. Sixteen studies were included in the review (N = 6085 patients). The performance of abdominal symptoms varied widely. The sensitivity of diarrhea, for example, ranged from 0.27 to 0.86 and specificity from 0.21 to 0.86. Pooled estimates for IgA antiendomysial antibodies (8 studies) were 0.90 (95% confidence interval [CI], 0.80-0.95) for sensitivity and 0.99 (95% CI, 0.98-1.00) for specificity (positive likelihood ratio [LR] of 171 and negative LR of 0.11). Pooled estimates for IgA antitissue transglutaminase antibodies (7 studies) were 0.89 (95% CI, 0.82-0.94) and 0.98 (95% CI, 0.95-0.99), respectively (positive LR of 37.7 and negative LR of 0.11). The IgA and IgG antigliadin antibodies showed variable results, especially for sensitivity (range, 0.46-0.87 and range, 0.25-0.93, respectively). One recent study using diamidated gliadin peptides showed good specificity (> or = 0.94), but evidence is limited in this target population. Among adult patients presenting with abdominal symptoms in primary care or other unselected populations, IgA antitissue transglutaminase antibodies and IgA antiendomysial antibodies have high sensitivity and specificity for diagnosing celiac disease.

Effects of Swiss-ball core strength training on strength, endurance, flexibility, and balance in sedentary women.

PubMed

Sekendiz, Betül; Cuğ, Mutlu; Korkusuz, Feza

2010-11-01

The purpose of this study was to investigate the effects of Swiss-ball core strength training on trunk extensor (abdominal)/flexor (lower back) and lower limb extensor (quadriceps)/flexor (hamstring) muscular strength, abdominal, lower back and leg endurance, flexibility and dynamic balance in sedentary women (n = 21; age = 34 ± 8.09; height = 1.63 ± 6.91 cm; weight = 64 ± 8.69 kg) trained for 45 minutes, 3 d·wk-1 for 12 weeks. Results of multivariate analysis revealed significant difference (p ≤ 0.05) between pre and postmeasures of 60 and 90° s trunk flexion/extension, 60 and 240° s-1 lower limb flexion/extension (Biodex Isokinetic Dynamometer), abdominal endurance (curl-up test), lower back muscular endurance (modified Sorensen test), lower limb endurance (repetitive squat test), lower back flexibility (sit and reach test), and dynamic balance (functional reach test). The results support the fact that Swiss-ball core strength training exercises can be used to provide improvement in the aforementioned measures in sedentary women. In conclusion, this study provides practical implications for sedentary individuals, physiotherapists, strength and conditioning specialists who can benefit from core strength training with Swiss balls.

Microtubules as key cytoskeletal elements in cellular transport and shape changes: their expected responses to space environments

NASA Technical Reports Server (NTRS)

Conrad, G. W.; Conrad, A. H.; Spooner, B. S. (Principal Investigator)

1992-01-01

Application of reference standard reagents to alternatively depolymerize or stabilize microtubules in a cell that undergoes very regular cytoskeleton-dependent shape changes provides a model system in which some expected components of the environments of spacecraft and space can be tested on Earth for their effects on the cytoskeleton. The fertilized eggs of Ilyanassa obsoleta undergo polar lobe formation by repeated, dramatic, constriction and relaxation of a microfilamentous band localized in the cortical cytoplasm and activated by microtubules.

Anti-inflammatory and analgesic activity of Peperomia pellucida (L.) HBK (Piperaceae).

PubMed

de Fátima Arrigoni-Blank, Maria; Dmitrieva, Elena G; Franzotti, Elaine Maria; Antoniolli, Angelo Roberto; Andrade, Márcio Roberto; Marchioro, Murilo

2004-04-01

An aqueous extract of the aerial part of Peperomia pellucida (L.) HBK (Piperaceae) was tested for anti-inflammatory (paw edema induced by carrageenin and arachidonic acid) and analgesic activity (abdominal writhes and hot plate) in rats and mice, respectively. Oral administration of 200 and 400 mg/kg of the aqueous extract exhibited an anti-inflammatory activity in the carrageenin test, which was based on interference with prostaglandin synthesis, as confirmed by the arachidonic acid test. In the abdominal writhing test induced by acetic acid, 400 mg/kg of the plant extract had the highest analgesic activity, whereas in the hot-plate test the best dose was 100 mg/kg. The LD(50) showed that Peperomia pellucida (5000 mg/kg) presented low toxicity.

Unexplained lower abdominal pain associated with sacroiliac joint dysfunction: report of 2 cases.

PubMed

Morimoto, Daijiro; Isu, Toyohiko; Kim, Kyongsong; Matsumoto, Ryoji; Isobe, Masanori

2011-01-01

A 25-year-old woman and a 31-year-old man presented with chronic lower back pain and unexplained lower abdominal pain. Both patients had groin tenderness at the medial border of the anterior superior iliac spine. The results of radiographical and physical examinations suggested sacroiliac joint dysfunction. Sacroiliac joint injection relieved their symptoms, including groin tenderness. In our experience, groin tenderness is highly specific for sacroiliac joint dysfunction. We speculate that spasm of the iliac muscle can cause groin pain and tenderness. Groin pain and a history of unexplained abdominal pain, with lower back pain, are symptoms that suggest sacroiliac joint dysfunction. Additionally, compression of the iliac muscle is a simple and useful maneuver; therefore, it can be used as a screening test for sacroiliac joint dysfunction, alongside other provocation tests.

Spot fat reduction by red and near infrared LED phototherapy

NASA Astrophysics Data System (ADS)

Lim, Sungkyoo; Park, Eal-Whan

2018-02-01

Low level light therapy (LLLT) using light from red and near infrared LEDs or Lasers have been reported effective as noninvasive methods for reducing spot fat. A total of 55 subjects were randomly divided into test groups and control groups for abdominal fat reduction clinical trial using red and near infrared LED phototherapy devices. Red and near infrared light with irradiance of 10 mW/cm2 were irradiated over the abdominal area to the test group for 30 minutes followed by 30 minutes of aerobic exercise, 3 times a week for 4 weeks. Control group used sham devices for 30 minutes and followed by 30 minutes of aerobic exercise. It is expected that red and near infrared LED phototherapy combined with aerobic exercise would be effective and safe for abdominal fat reduction without any side effects.

Radioactive nondestructive test method

NASA Technical Reports Server (NTRS)

Obrien, J. R.; Pullen, K. E.

1971-01-01

Various radioisotope techniques were used as diagnostic tools for determining the performance of spacecraft propulsion feed system elements. Applications were studied in four tasks. The first two required experimental testing involving the propellant liquid oxygen difluoride (OF2): the neutron activation analysis of dissolved or suspended metals, and the use of radioactive tracers to evaluate the probability of constrictions in passive components (orifices and filters) becoming clogged by matter dissolved or suspended in the OF2. The other tasks were an appraisal of the applicability of radioisotope techniques to problems arising from the exposure of components to liquid/gas combinations, and an assessment of the applicability of the techniques to other propellants.

Mechanical Intestinal Obstruction in a Porcine Model: Effects of Intra-Abdominal Hypertension. A Preliminary Study

PubMed Central

Sánchez-Margallo, F. M.; Latorre, R.; López-Albors, O.; Wise, R.; Malbrain, M. L. N. G.; Castellanos, G.

2016-01-01

Introduction Mechanical intestinal obstruction is a disorder associated with intra-abdominal hypertension and abdominal compartment syndrome. As the large intestine intraluminal and intra-abdominal pressures are increased, so the patient’s risk for intestinal ischaemia. Previous studies have focused on hypoperfusion and bacterial translocation without considering the concomitant effect of intra-abdominal hypertension. The objective of this study was to design and evaluate a mechanical intestinal obstruction model in pigs similar to the human pathophysiology. Materials and Methods Fifteen pigs were divided into three groups: a control group (n = 5) and two groups of 5 pigs with intra-abdominal hypertension induced by mechanical intestinal obstruction. The intra-abdominal pressures of 20 mmHg were maintained for 2 and 5 hours respectively. Hemodynamic, respiratory and gastric intramucosal pH values, as well as blood tests were recorded every 30 min. Results Significant differences between the control and mechanical intestinal obstruction groups were noted. The mean arterial pressure, cardiac index, dynamic pulmonary compliance and abdominal perfusion pressure decreased. The systemic vascular resistance index, central venous pressure, pulse pressure variation, airway resistance and lactate increased within 2 hours from starting intra-abdominal hypertension (p<0.05). In addition, we observed increased values for the peak and plateau airway pressures, and low values of gastric intramucosal pH in the mechanical intestinal obstruction groups that were significant after 3 hours. Conclusion The mechanical intestinal obstruction model appears to adequately simulate the pathophysiology of intestinal obstruction that occurs in humans. Monitoring abdominal perfusion pressure, dynamic pulmonary compliance, gastric intramucosal pH and lactate values may provide insight in predicting the effects on endorgan function in patients with mechanical intestinal obstruction. PMID:26849559

Low-threshold high-T/0/ constricted double heterojunction AlGaAs diode lasers

NASA Technical Reports Server (NTRS)

Botez, D.; Connolly, J. C.

1980-01-01

Constricted double heterojunction diode lasers of relatively low CW thresholds (28-40 mA) are obtained by growing structures that maximize the amount of current flow into the lasing spot. These values are obtained while still using standard 10 microns wide oxide-defined stripe contacts. Over the 20-70 C temperature interval, threshold current temperature coefficients as high as 320 C and a virtually constant external differential quantum efficiency, are found.

[Expression of A-type atrial natriuretic peptide receptor in the kidneys of renovascular hypertension rats and its implication].

PubMed

Liu, Rong-Tao; Xiao, Jing; Guo, Hui-Ling; Qiu, Dun-Guo; Yin, Hua-Hu; Wang, Zheng-Rong

2005-11-01

To investigate the expression of A-type atrial natriuretic peptide receptor (ANPR-A) in the kidneys of renovascular hypertension rats and evaluate the significance of the expression. The rat model of renovascular hypertension was produced by constricting one lateral renal artery. After the renal artery being constricted for 4 weeks and 8 weeks, the systolic BP of rats was measured with a manometer using the tail-cuff method. Then, the expression of ANPR-A was respectively detected by immunohistochemical technique in the kidneys of the two-kidney, one-clip (2K1C) rats, and the expression level of ANPR-A was semi-quantitatively measured by Mias-2000 computer image analyzer. At 4 weeks after the artery-constricted operation,the expression of ANPR-A increased significantly in 2K1C hypertensive rat glomeruli and decreased significantly in renal tubules, compared with control (P<0.01), but there was no marked change in medullar collecting tubules. At 8 weeks after the artery-constricted operation, the expression of ANPR-A decreased significantly in 2K1C hypertensive rat renal tubules and medullar collecting tubules, compared with control (P<0.01); however, there was weak expression in glomeruli, and no statistically significant difference was seen when compared with control (P>0.05). The expression of ANPR-A decreased significantly in kidney tissues of renovascular

Theory of vibratory mobilization and break-up of non-wetting fluids entrapped in pore constrictions

NASA Astrophysics Data System (ADS)

Beresnev, I.; Li, W.; Vigil, D.

2006-12-01

Quantitative dynamics of a non-wetting (e. g., NAPL) ganglion entrapped in a pore constriction and subjected to vibrations can be approximated by the equation of motion of an oscillator moving under the effect of the external pressure gradient, inertial oscillatory force, and restoring capillary force. The solution of the equation provides the conditions under which the droplet experiences forced oscillations without being mobilized or is liberated upon the acceleration of the wall exceeding an "unplugging" threshold. This solution provides a quantitative tool for the estimation of the parameters of vibratory fields needed to liberate entrapped non-wetting fluids. For typical pore sizes encountered in reservoirs and aquifers, wall accelerations must exceed at least several m/sec2 and even higher levels to mobilize the droplets of NAPL; however, in the populations of ganglia entrapped in natural porous environments, many may reside very near their mobilization thresholds and may be mobilized by extremely low accelerations as well. For given acceleration, lower seismic frequencies are more efficient. The ganglia may also break up into smaller pieces when passing through pore constrictions. The snap-off is governed by the geometry only; for constrictions with sinusoidal profile (spatial wavelength of L and maximum and minimum radii of rmax and rmin, the break-up occurs if L > 2π(rmin rmax)1/2. Computational fluid dynamics shows the details of the break-up process.

The Characterization of AT1 Expression in the Dorsal Root Ganglia After Chronic Constriction Injury.

PubMed

Oroszova, Zuzana; Hricova, Ludmila; Stropkovska, Andrea; Lukacova, Nadezda; Pavel, Jaroslav

2017-04-01

To clarify the role of Angiotensin II in the regulation of sensory signaling, we characterized the AT 1 expression in neuronal subpopulation of lower lumbar dorsal root ganglia under normal conditions and its alteration in neuropathic pain model. The characterization of AT 1 expression was done under control and after the chronic constriction injury induced by four loose ligatures of the sciatic nerve representing the model of posttraumatic painful peripheral neuropathy. Major Angiotensin II receptor type was expressed in approximately 43 % of small-sized and 62 % of large-sized neurons in control. The AT 1 overexpression after sciatic nerve ligation lasting 7 days was detected predominantly in small-sized AT 1 immunoreactive neurons (about 38 % increase). Chronic constriction injury caused a statistically marked increase in number of the small-sized peptidergic (CGRP immunoreactive) neuronal subpopulation expressing AT 1 (about 64 %). The subpopulations of AT 1 -immunoreactive and nonpeptide-containing primary sensory neurons revealed by IB4 binding, tyrosine hydroxylase- and parvalbumin-immunoreactive neurons were not markedly changed. Our results indicate that: (1) the AT 1 overexpression after the chronic constriction injury is an important factor in Angiotensin II-potentiated pain perception; (2) Angiotensin II is involved in pathological mechanisms of neuropathic pain and this effect can be mediated perhaps in combination with other neuropeptides synthesized in the primary sensory neurons.

Low-dose thromboxane A2 receptor stimulation promotes closure of the rat ductus arteriosus with minimal adverse effects.

PubMed

Yokota, Tomohiro; Aida, Takashi; Ichikawa, Yasuhiro; Fujita, Takayuki; Yokoyama, Utako; Minamisawa, Susumu

2012-08-01

Patent ductus arteriosus (PDA) is a common life-threatening complication among premature infants. Although cyclooxygenase inhibitors are frequently used to treat PDA, as they inhibit the synthesis of prostaglandin E(2), the most potent vasodilator in the ductus arteriosus (DA), their efficacy is often limited. As thromboxane A(2) (TXA(2)) induces vascular contraction via the TXA(2) receptor (TP), we hypothesized that TP stimulation would promote DA closure. To measure the inner diameter of the vessels, a rapid whole-body freezing method was used. Injection of the selective TP agonists U46619 and I-BOP constricted the fetal DA at embryonic day 19 (e19) and e21 in a dose-dependent manner. Of note, U46619 also exerted a vasoconstrictive effect on two different types of postnatal PDA models: premature PDA and hypoxia-induced PDA. We also found that U46619 constricted the ex vivo DA ring to a greater extent than it constricted the ex vivo aorta. Furthermore, we found that U46619 at lower concentrations (up to 0.05 mg/g of body weight) had a minimal vasoconstrictive effect on other vessels and did not induce microthrombosis in the pulmonary capillary arteries. Low-dose TP stimulation constricts the DA with minimal adverse effects at least in rat neonates and our results could point to an alternative potent vasoconstrictor for PDA.

Scaling down constriction-based (electrodeless) dielectrophoresis devices for trapping nanoscale bioparticles in physiological media of high-conductivity.

PubMed

Chaurey, Vasudha; Rohani, Ali; Su, Yi-Hsuan; Liao, Kuo-Tang; Chou, Chia-Fu; Swami, Nathan S

2013-04-01

Selective trapping of nanoscale bioparticles (size <100 nm) is significant for the separation and high-sensitivity detection of biomarkers. Dielectrophoresis is capable of highly selective trapping of bioparticles based on their characteristic frequency response. However, the trapping forces fall steeply with particle size, especially within physiological media of high-conductivity where the trapping can be dissipated by electrothermal (ET) flow due to localized Joule heating. Herein, we investigate the influence of device scaling within the electrodeless insulator dielectrophoresis geometry through the application of highly constricted channels of successively smaller channel depth, on the net balance of dielectrophoretic trapping force versus ET drag force on bioparticles. While higher degrees of constriction enable dielectrophoretic trapping of successively smaller bioparticles within a short time, the ETflow due to enhanced Joule heating within media of high conductivity can cause a significant dissipation of bioparticle trapping. This dissipative drag force can be reduced through lowering the depth of the highly constricted channels to submicron sizes, which substantially reduces the degree of Joule heating, thereby enhancing the range of voltages and media conductivities that can be applied toward rapid dielectrophoretic concentration enrichment of silica nanoparticles (∼50 nm) and streptavidin protein biomolecules (∼5 nm). We envision the application of these methodologies toward nanofabrication, optofluidics, biomarker discovery, and early disease diagnostics. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Abdominal fat volume estimation by stereology on CT: a comparison with manual planimetry.

PubMed

Manios, G E; Mazonakis, M; Voulgaris, C; Karantanas, A; Damilakis, J

2016-03-01

To deploy and evaluate a stereological point-counting technique on abdominal CT for the estimation of visceral (VAF) and subcutaneous abdominal fat (SAF) volumes. Stereological volume estimations based on point counting and systematic sampling were performed on images from 14 consecutive patients who had undergone abdominal CT. For the optimization of the method, five sampling intensities in combination with 100 and 200 points were tested. The optimum stereological measurements were compared with VAF and SAF volumes derived by the standard technique of manual planimetry on the same scans. Optimization analysis showed that the selection of 200 points along with the sampling intensity 1/8 provided efficient volume estimations in less than 4 min for VAF and SAF together. The optimized stereology showed strong correlation with planimetry (VAF: r = 0.98; SAF: r = 0.98). No statistical differences were found between the two methods (VAF: P = 0.81; SAF: P = 0.83). The 95% limits of agreement were also acceptable (VAF: -16.5%, 16.1%; SAF: -10.8%, 10.7%) and the repeatability of stereology was good (VAF: CV = 4.5%, SAF: CV = 3.2%). Stereology may be successfully applied to CT images for the efficient estimation of abdominal fat volume and may constitute a good alternative to the conventional planimetric technique. Abdominal obesity is associated with increased risk of disease and mortality. Stereology may quantify visceral and subcutaneous abdominal fat accurately and consistently. The application of stereology to estimating abdominal volume fat reduces processing time. Stereology is an efficient alternative method for estimating abdominal fat volume.

Hyperandrogenism Accompanies Increased Intra-Abdominal Fat Storage in Normal Weight Polycystic Ovary Syndrome Women.

PubMed

Dumesic, Daniel A; Akopians, Alin L; Madrigal, Vanessa K; Ramirez, Emmanuel; Margolis, Daniel J; Sarma, Manoj K; Thomas, Albert M; Grogan, Tristan R; Haykal, Rasha; Schooler, Tery A; Okeya, Bette L; Abbott, David H; Chazenbalk, Gregorio D

2016-11-01

Normal weight polycystic ovary syndrome (PCOS) women may have altered adipose structure-function underlying metabolic dysfunction. This study examines whether adipose structure-functional changes exist in normal weight PCOS women and correlate with hyperandrogenism and/or hyperinsulinemia. This is a prospective cohort study. The setting was an academic medical center. Six normal weight PCOS women and 14 age- and body mass index-matched normoandrogenic ovulatory (NL) women were included. All women underwent circulating hormone and metabolic measurements; frequently sampled intravenous glucose tolerance testing; total body dual-energy x-ray absorptiometry; abdominal magnetic resonance imaging; and SC abdominal fat biopsy. Circulating hormones and metabolites, body fat and its distribution, and adipocyte size were compared between PCOS and NL women, and were correlated with each other in all women. Circulating LH and androgen levels were significantly greater in PCOS than NL women, as were fasting insulin levels, pancreatic β-cell responsiveness to glucose, and total abdominal fat mass. Intra-abdominal fat mass also was significantly increased in PCOS women and was positively correlated with circulating androgen, fasting insulin, triglyceride, and non-high-density lipoprotein cholesterol levels in all women. SC abdominal fat mass was not significantly increased in PCOS women, but contained a greater proportion of small SC abdominal adipocytes that positively correlated with serum androgen levels in all women. Hyperandrogenism in normal weight PCOS women is associated with preferential intra-abdominal fat deposition and an increased population of small SC abdominal adipocytes that could constrain SC adipose storage and promote metabolic dysfunction.

Surface Electromyographic Activity of the Abdominal Muscles During Pelvic-Tilt and Abdominal-Hollowing Exercises

PubMed Central

Drysdale, Cheri L.; Earl, Jennifer E.

2004-01-01

Objective: To investigate surface electromyographic (EMG) activity of the rectus abdominus and external oblique abdominus muscles during pelvic-tilt and abdominal-hollowing exercises performed in different positions. Design and Setting: 2 × 3 (exercise by position) within-subjects design with repeated measures on both factors. All testing was performed in a university laboratory. Subjects: Twenty-six healthy, active young adult females. Measurements: Surface EMG activity was recorded from the left and right rectus abdominus and external oblique muscles while the 2 exercises (pelvic tilt and abdominal hollowing) were performed in different positions (standard, legs supported, and legs unsupported). The standard position was supine in the crook-lying position, the supported position was with hips and knees flexed to 90° and legs supported on a platform, and the unsupported position was with hips and knees flexed to 90° without external support. Peak EMG activity was normalized to a maximum voluntary isometric contraction for each muscle. Results: For the rectus abdominus, there was an interaction between position and activity. Abdominal hollowing produced significantly less activity than the pelvic tilt in all positions. The difference between the 2 exercises with the legs unsupported was of a greater magnitude than the other 2 positions. For the external obliques, there was significantly lower activity during the abdominal hollowing compared with the pelvic tilting. The greatest muscle activity occurred with the legs-unsupported position during both exercises. Conclusions: Abdominal-hollowing exercises produced less rectus abdominus and external oblique activity than pelvic-tilting exercises. Abdominal hollowing may be performed with minimal activation of the large global abdominal muscles. PMID:15085209

Surface Electromyographic Activity of the Abdominal Muscles During Pelvic-Tilt and Abdominal-Hollowing Exercises.

PubMed

Drysdale, Cheri L.; Earl, Jennifer E.; Hertel, Jay

2004-03-01

OBJECTIVE: To investigate surface electromyographic (EMG) activity of the rectus abdominus and external oblique abdominus muscles during pelvic-tilt and abdominal-hollowing exercises performed in different positions. DESIGN AND SETTING: 2 x 3 (exercise by position) within-subjects design with repeated measures on both factors. All testing was performed in a university laboratory. SUBJECTS: Twenty-six healthy, active young adult females. MEASUREMENTS: Surface EMG activity was recorded from the left and right rectus abdominus and external oblique muscles while the 2 exercises (pelvic tilt and abdominal hollowing) were performed in different positions (standard, legs supported, and legs unsupported). The standard position was supine in the crook-lying position, the supported position was with hips and knees flexed to 90 degrees and legs supported on a platform, and the unsupported position was with hips and knees flexed to 90 degrees without external support. Peak EMG activity was normalized to a maximum voluntary isometric contraction for each muscle. RESULTS: For the rectus abdominus, there was an interaction between position and activity. Abdominal hollowing produced significantly less activity than the pelvic tilt in all positions. The difference between the 2 exercises with the legs unsupported was of a greater magnitude than the other 2 positions. For the external obliques, there was significantly lower activity during the abdominal hollowing compared with the pelvic tilting. The greatest muscle activity occurred with the legs-unsupported position during both exercises. CONCLUSIONS: Abdominal-hollowing exercises produced less rectus abdominus and external oblique activity than pelvic-tilting exercises. Abdominal hollowing may be performed with minimal activation of the large global abdominal muscles.

FAST for blunt abdominal trauma: Correlation between positive findings and admission acid-base measurement.

PubMed

Heidari, Kamran; Taghizadeh, Mehrdad; Mahmoudi, Sadrollah; Panahi, Hamidreza; Ghaffari Shad, Ensieh; Asadollahi, Shadi

2017-06-01

This study aimed to determine any association between positive findings in ultrasonography examination and initial BD value with regard to diagnosis of intra-abdominal bleeding following blunt abdominal trauma. A prospective, multi-center study of consecutive adult patients was performed from April to September 2015. Demographics, initial vital signs and arterial BD were evaluated with respect to presence of any association with intra-abdominal bleeding and in-hospital mortality. FAST study was performed to find intra-abdominal bleeding. Receiver operating characteristic (ROC) curves tested the ability of BD to identify patients with intra-abdominal hemorrhage and probable mortality. A total of 879 patients were included in final analysis. The mean (SD) age was 36.68 (15.7) years and 714 patients (81.2%) were male. According to multivariable analysis, statistically significant association was observed between negative admission BD and both intra-abdominal bleeding (OR 3.48, 95% CI 2.06-5.88, p<0.001) and in-hospital mortality (OR 1.55, 95% CI 1.49-1.63, p<0.001). ROC curve analysis demonstrated sensitivity of 92.7% and specificity of 22.1% for the best cut-off value of BD (-8mEq/L) to diagnose internal hemorrhage. Further, a cut-off value of -7mEq/L demonstrated significant predictive performance, 94.8% sensitivity and 53.6% specificity for in-hospital mortality. This study revealed that arterial BD is an early accessible important marker to identify intra-abdominal bleeding, as well as to predict overall in-hospital mortality in patients with blunt abdominal trauma. Copyright © 2017. Published by Elsevier Inc.

Mechanisms of postprandial abdominal bloating and distension in functional dyspepsia.

PubMed

Burri, Emanuel; Barba, Elizabeth; Huaman, Jose Walter; Cisternas, Daniel; Accarino, Anna; Soldevilla, Alfredo; Malagelada, Juan-R; Azpiroz, Fernando

2014-03-01

Patients with irritable bowel syndrome and abdominal bloating exhibit abnormal responses of the abdominal wall to colonic gas loads. We hypothesised that in patients with postprandial bloating, ingestion of a meal triggers comparable abdominal wall dyssynergia. Our aim was to characterise abdominal accommodation to a meal in patients with postprandial bloating. A test meal (0.8 kcal/ml nutrients plus 27 g/litre polyethylenglycol 4000) was administered at 50 ml/min as long as tolerated in 10 patients with postprandial bloating (fulfilling Rome III criteria for postprandial distress syndrome) and 12 healthy subjects, while electromyographic (EMG) responses of the anterior wall (upper and lower rectus, external and internal oblique via bipolar surface electrodes) and the diaphragm (via six ring electrodes over an oesophageal tube in the hiatus) were measured. Means +/- SD were calculated. Healthy subjects tolerated a meal volume of 913±308 ml; normal abdominal wall accommodation to the meal consisted of diaphragmatic relaxation (EMG activity decreased by 15±6%) and a compensatory contraction (25±9% increase) of the upper abdominal wall muscles (upper rectus and external oblique), with no changes in the lower anterior muscles (lower rectus and internal oblique). Patients tolerated lower volume loads (604±310 ml; p=0.030 vs healthy subjects) and developed a paradoxical response, that is, diaphragmatic contraction (14±3% EMG increment; p<0.01 vs healthy subjects) and upper anterior wall relaxation (9±4% inhibition; p<0.01 vs healthy subjects). In functional dyspepsia, postprandial abdominal distension is produced by an abnormal viscerosomatic response to meal ingestion that alters normal abdominal accommodation.

Antinociceptive effects of oxymatrine from Sophora flavescens, through regulation of NR2B-containing NMDA receptor-ERK/CREB signaling in a mice model of neuropathic pain.

PubMed

Wang, Haiyan; Li, Yuxiang; Dun, Linglu; Xu, Yaqiong; Jin, Shaojv; Du, Juan; Ma, Lin; Li, Juan; Zhou, Ru; He, Xiaoliang; Sun, Tao; Yu, Jianqiang

2013-08-15

In this study we investigated antinociceptive effects of oxymatrine through regulation of NR2B-containing NMDA receptor-ERK/CREB signaling in a chronic neuropathic pain model induced by chronic constrictive injury (CCI) of the sciatic nerve. The von Frey and plantar tests were performed to assess the degree of mechanical and thermal changes respectively. Immunohistochemistry assay was used to evaluate the expressions of NR2B. Western blotting assay were used to evaluate the expressions of NR2B, tERK, p-ERK, tCREB and p-CREB. The intraperitoneal administration of OMT (160, 80 mg/kg) could prevent the development of mechanical allodynia, thermal hyperalgesia induced by CCI. Intraperitoneal administration of OMT decreased the mean IOD of NR2B in the dorsal horn and expression of NR2B, p-ERK and p-CREB protein. Regulation of NMDA NR2B receptor-ERK/CREB signaling maybe the targets for the antinociceptive effects of OMT on a chronic neuropathic pain model induced by chronic constrictive injury of the sciatic nerve. Copyright © 2013 Elsevier GmbH. All rights reserved.

Childhood functional abdominal pain: mechanisms and management.

PubMed

Korterink, Judith; Devanarayana, Niranga Manjuri; Rajindrajith, Shaman; Vlieger, Arine; Benninga, Marc A

2015-03-01

Chronic abdominal pain is one of the most common clinical syndromes encountered in day to day clinical paediatric practice. Although common, its definition is confusing, predisposing factors are poorly understood and the pathophysiological mechanisms are not clear. The prevailing viewpoint in the pathogenesis involves the inter-relationship between changes in hypersensitivity and altered motility, to which several risk factors have been linked. Making a diagnosis of functional abdominal pain can be a challenge, as it is unclear which further diagnostic tests are necessary to exclude an organic cause. Moreover, large, well-performed, high-quality clinical trials for effective agents are lacking, which undermines evidence-based treatment. This Review summarizes current knowledge regarding the epidemiology, pathophysiology, risk factors and diagnostic work-up of functional abdominal pain. Finally, management options for children with functional abdominal pain are discussed including medications, dietary interventions, probiotics and psychological and complementary therapies, to improve understanding and to maximize the quality of care for children with this condition.

An In-depth Study of Abdominal Injuries Sustained by Car Occupants in Frontal Crashes

PubMed Central

Frampton, Richard; Lenard, James; Compigne, Sabine

2012-01-01

Currently, neither abdominal injury risk nor rear seat passenger safety is assessed in European frontal crash testing. The objective of this study was to provide real world in-depth analysis of the factors related to abdominal injury for belted front and rear seat occupants in frontal crashes. Rear occupants were significantly more at risk of AIS 2+ and 3+ abdominal injury, followed by front seat passengers and then drivers. This was still the case even after controlling for occupant age. Increasing age was separately identified as a factor related to increased abdominal injury risk in all seating positions. One exception to this trend concerned rear seated 15 to 19 year olds who sustained moderate to serious abdominal injury at almost the same rate as rear occupants aged 65+.No strong association was seen between AIS 2+ abdominal injury rates and gender. The majority of occupant body mass indices ranged from underweight to obese. Across that range, the AIS 2+ abdominal injury rates were very similar but a small number of very obese and extremely obese occupants outside of the range did exhibit noticeably higher rates. An analysis of variance in the rate of AIS 2+ abdominal injury with different restraint systems showed that simple belt systems, as used by most rear seat passengers, were the least protective. Increasing sophistication of the restraint system was related to lower rates of injury. The ANOVA also confirmed occupant age and crash severity as highly associated with abdominal injury risk. The most frequently injured abdominal organs for front seat occupants were the liver and spleen. Abdominal injury patterns for rear seat passengers were very different. While they also sustained significant injuries to solid organs, their rates of injury to the hollow organs (jejunum-ileum, mesentary, colon) were far higher even though the rate of fracture of two or more ribs did not differ significantly between seat positions. These results have implications for the design of restraint systems, particularly in relation to the occurrence of abdominal injury. They also raise issues of crash protection for older occupants as well as the protection afforded in different seating positions. PMID:23169124

Lead intoxication due to ayurvedic medications as a cause of abdominal pain in adults.

PubMed

Mehta, Varun; Midha, Vandana; Mahajan, Ramit; Narang, Vikram; Wander, Praneet; Sood, Ridhi; Sood, Ajit

2017-02-01

Though a majority of cases of lead intoxication come from occupational exposures, traditional and folk remedies have also been reported to contain toxic amounts of lead. We present a large series of patients with lead poisoning due to intake of Ayurvedic medicines, all of whom presented with unexplained abdominal pain. This was a retrospective, observational case series from a tertiary care center in India. The charts of patients who underwent blood lead level (BLL) testing as a part of workup for unexplained abdominal pain between 2005 and 2013 were reviewed. The patients with lead intoxication (BLLs >25 μg/dl) were identified and demographics, history, possible risk factors, clinical presentation and investigations were reviewed. Treatment details, duration, time to symptomatic recovery, laboratory follow-up and adverse events during therapy were recorded. BLLs were tested in 786 patients with unexplained abdominal pain and high levels were identified in 75 (9.5%) patients, of which a majority (73 patients, 9.3%) had history of Ayurvedic medication intake and only two had occupational exposure. Five randomly chosen Ayurvedic medications were analyzed and lead levels were impermissibly high (14-34,950 ppm) in all of them. Besides pain in abdomen, other presenting complaints were constipation, hypertension, neurological symptoms and acute kidney injury. Anemia and abnormal liver biochemical tests were observed in all the 73 patients. Discontinuing the Ayurvedic medicines and chelation with d-penicillamine led to improvement in symptoms and reduction in BLLs in all patients within 3-4 months. The patients presenting with severe recurrent abdominal pain, anemia and history of use of Ayurvedic medicines should be evaluated for lead toxicity. Early diagnosis in such cases can prevent unnecessary investigations and interventions, and permits early commencement of the treatment.

What controls open-pore and residual currents in the first sensing zone of alpha-hemolysin nanopore? Combined experimental and theoretical study

NASA Astrophysics Data System (ADS)

de Biase, Pablo M.; Ervin, Eric N.; Pal, Prithwish; Samoylova, Olga; Markosyan, Suren; Keehan, Michael G.; Barrall, Geoffrey A.; Noskov, Sergei Yu.

2016-06-01

The electrophoretic transport of single-stranded DNA through biological nanopores such as alpha-hemolysin (αHL) is a promising and cost-effective technology with the potential to revolutionize genomics. The rational design of pores with the controlled polymer translocation rates and high contrast between different nucleotides could improve significantly nanopore sequencing applications. Here, we apply a combination of theoretical and experimental methods in an attempt to elucidate several selective modifications in the pore which were proposed to be central for the effective discrimination between purines and pyrimidines. Our nanopore test set includes the wild type αHL and six mutants (E111N/M113X/K147N) in which the cross-section and chemical functionality of the first constriction zone of the pore are modified. Electrophysiological recordings were combined with all-atom Molecular Dynamics simulations (MD) and a recently developed Brownian Dynamics (BROMOC) protocol to investigate residual ion currents and pore-DNA interactions for two homo-polymers e.g. poly(dA)40 or poly(dC)40 blocking the pore. The calculated residual currents and contrast in the poly(dA)40/poly(dC)40 blocked pore are in qualitative agreement with the experimental recordings. We showed that a simple structural metric allows rationalization of key elements in the emergent contrast between purines and pyrimidines in the modified αHL mutants. The shape of the pore and its capacity for hydrogen bonding to a translocated polynucleotide are two essential parameters for contrast optimization. To further probe the impact of these two factors in the ssDNA sensing, we eliminated the effect of the primary constriction using serine substitutions (i.e. E111S/M113S/T145S/K147S) and increased the hydrophobic volume of the central residue in the secondary constriction (L135I). This pore modification sharply increased the contrast between Adenine (A) and Cytosine (C).The electrophoretic transport of single-stranded DNA through biological nanopores such as alpha-hemolysin (αHL) is a promising and cost-effective technology with the potential to revolutionize genomics. The rational design of pores with the controlled polymer translocation rates and high contrast between different nucleotides could improve significantly nanopore sequencing applications. Here, we apply a combination of theoretical and experimental methods in an attempt to elucidate several selective modifications in the pore which were proposed to be central for the effective discrimination between purines and pyrimidines. Our nanopore test set includes the wild type αHL and six mutants (E111N/M113X/K147N) in which the cross-section and chemical functionality of the first constriction zone of the pore are modified. Electrophysiological recordings were combined with all-atom Molecular Dynamics simulations (MD) and a recently developed Brownian Dynamics (BROMOC) protocol to investigate residual ion currents and pore-DNA interactions for two homo-polymers e.g. poly(dA)40 or poly(dC)40 blocking the pore. The calculated residual currents and contrast in the poly(dA)40/poly(dC)40 blocked pore are in qualitative agreement with the experimental recordings. We showed that a simple structural metric allows rationalization of key elements in the emergent contrast between purines and pyrimidines in the modified αHL mutants. The shape of the pore and its capacity for hydrogen bonding to a translocated polynucleotide are two essential parameters for contrast optimization. To further probe the impact of these two factors in the ssDNA sensing, we eliminated the effect of the primary constriction using serine substitutions (i.e. E111S/M113S/T145S/K147S) and increased the hydrophobic volume of the central residue in the secondary constriction (L135I). This pore modification sharply increased the contrast between Adenine (A) and Cytosine (C). Electronic supplementary information (ESI) available: Statistical data on correlation between experimental and predicted conductance, ion densities in open and blocked pores and data on solvent structuring in nanopores. See DOI: 10.1039/c6nr00164e

Subadditive responses to extremely short blue and green pulsed light on visual evoked potentials, pupillary constriction and electroretinograms.

PubMed

Lee, Soomin; Uchiyama, Yuria; Shimomura, Yoshihiro; Katsuura, Tetsuo

2017-11-17

The simultaneous exposure to blue and green light was reported to result in less melatonin suppression than monochromatic exposure to blue or green light. Here, we conducted an experiment using extremely short blue- and green-pulsed light to examine their visual and nonvisual effects on visual evoked potentials (VEPs), pupillary constriction, electroretinograms (ERGs), and subjective evaluations. Twelve adult male subjects were exposed to three light conditions: blue-pulsed light (2.5-ms pulse width), green-pulsed light (2.5-ms pulse width), and simultaneous blue- and green-pulsed light with white background light. We measured the subject's pupil diameter three times in each condition. Then, after 10 min of rest, the subject was exposed to the same three light conditions. We measured the averaged ERG and VEP during 210 pulsed-light exposures in each condition. We also determined subjective evaluations using a visual analog scale (VAS) method. The pupillary constriction during the simultaneous exposure to blue- and green-pulsed light was significantly lower than that during the blue-pulsed light exposure despite the double irradiance intensity of the combination. We also found that the b/|a| wave of the ERGs during the simultaneous exposure to blue- and green-pulsed light was lower than that during the blue-pulsed light exposure. We confirmed the subadditive response to pulsed light on pupillary constriction and ERG. However, the P100 of the VEPs during the blue-pulsed light were smaller than those during the simultaneous blue- and green-pulsed light and green-pulsed light, indicating that the P100 amplitude might depend on the luminance of light. Our findings demonstrated the effect of the subadditive response to extremely short pulsed light on pupillary constriction and ERG responses. The effects on ipRGCs by the blue-pulsed light exposure are apparently reduced by the simultaneous irradiation of green light. The blue versus yellow (b/y) bipolar cells in the retina might be responsible for this phenomenon.

Retinal vessel diameters and reactivity in diabetes mellitus and/or cardiovascular disease.

PubMed

Heitmar, R; Lip, G Y H; Ryder, R E; Blann, A D

2017-04-26

Retinal vessel calibre and vascular dilation/constriction in response to flicker light provocation may provide a measure distinguishing patients suffering from diabetes mellitus and/or cardiovascular disease. One hundred and sixteen age and sex matched patients with diabetes mellitus (DM), cardiovascular disease (CVD) and both DM and CVD (DM + CVD) underwent systemic and intraocular pressure measurements. Retinal vessel calibres were assessed using a validated computer-based program to compute central retinal artery and vein equivalents (CRVE) from monochromatic retinal images. Vessel dilation and constriction responses to flicker light provocation were assessed by continuous retinal vessel diameter recordings. Plasma endothelial markers von Willebrand factor (vWf) and soluble E selectin (sEsel) were measured by ELISA. Retinal vessel calibres were comparable across groups but CRVE correlated significantly with disease duration in DM patients (r = 0.57, p < 0.001). Patients suffering DM only exhibited reduced arterial vasomotion at rest and reduced arterial constriction following flicker light induced vessel dilation compared to patients with CVD and those suffering both CVD + DM (p = 0.030). Patients suffering from CVD + DM exhibited significant differences between each flicker cycle in regards to arterial maximum constriction (p = 0.006) and time needed to reach arterial maximum dilation (p = 0.004), whereas the other two groups did not show such inconsistencies between individual flicker cycles. vWf was raised in CVD + DM compared to the other two groups (p ≤ 0.02), whilst sEsel was raised in CVD + DM compared to DM alone (p = 0.044). Dynamic retinal vascular calibres as obtained by continuous diameter measurements using flicker light provocation can reveal subtle differences between groups suffering from CVD with and without DM. This difference in reaction pattern and lack of arterial constriction in DM may provide a suitable marker to monitor progression.

Breast cancer amelioration by Butea monosperma in-vitro and in-vivo.

PubMed

Karia, Prachi; Patel, Kirti V; Rathod, Shri S P

2018-05-10

Butea monosperma belonging to family Fabaceae is used in the Indian traditional medicine (Ayurveda) for various ailments including abdominal tumors and possess anti-estrogenic activity. The present study is aimed at investigating the chemo-preventive potential of Butea monosperma in breast cancer and elucidating it's mechanism of action by assessing its effect on key processes like apoptosis, angiogenesis and metastasis. Cytotoxic potential of methanol extract of Butea monosperma flower (MEBM) was tested in MCF-7 (estrogen receptor positive), MDA-MB-231 (triple negative) and MDA-MB-453 (HER2 positive) human breast cancer cells by MTT assay. Chemo-preventive potential was evaluated in-vivo in Methylnitrosourea (MNU) induced mammary cancer in nulliparous Sprague-Dawley rats. The mechanism for anticancer potential was screened by in-vitro studies involving Annexin V- FITC assay (apoptosis), Chick Chorioallantoic Membrane assay (angiogenesis) and Migration assay (metastasis). Statistical analysis was done by one way and two way ANOVA (for Growth Rate and feed consumption efficiency) followed by post hoc Bonferroni's test with P value < 0.05. It is observed that the exposure of MEBM, at various concentrations and time intervals to different cell lines, resulted in decreased cell proliferation. The IC 50 value of MCF-7 cells was found significantly less than that of MDA-MB-231 and MDA-MB-453 cells, which indicated that the extract of said medicinal plant were more potent inhibitors of estrogen positive breast cancer cells than other types of breast cancer cells in vitro. Corroborative evidences were acquired in MNU actuated mammary carcinogenesis where MEBM constricted tumor parameters, decreased expression of estrogen and progesterone, nucleic acid content and increased latency period. MEBM also induced apoptosis, inhibited angiogenesis and metastasis in-vitro. Selective cytotoxic activity in MCF-7 estrogen positive breast cancer cells and inhibition of growth of mammary carcinoma in-vivo by methanol extract of Butea monosperma flowers (MEBM) suggests chemo-prevention through modulation of estrogen and progesterone receptor, apoptotic, anti-angiogenesis and anti-metastatic activity. Copyright © 2017 Elsevier B.V. All rights reserved.

The respiratory pressure-abdominal volume curve in a porcine model.

PubMed

Regli, Adrian; De Keulenaer, Bart Leon; Singh, Bhajan; Hockings, Lisen Emma; Noffsinger, Bill; van Heerden, Peter Vernon

2017-12-01

Increasing intra-abdominal volume (IAV) can lead to intra-abdominal hypertension (IAH) or abdominal compartment syndrome. Both are associated with raised morbidity and mortality. IAH can increase airway pressures and impair ventilation. The relationship between increasing IAV and airway pressures is not known. We therefore assessed the effect of increasing IAV on airway and intra-abdominal pressures (IAP). Seven pigs (41.4 +/-8.5 kg) received standardized anesthesia and mechanical ventilation. A latex balloon inserted in the peritoneal cavity was inflated in 1-L increments until IAP exceeded 40 cmH 2 O. Peak airway pressure (pP AW ), respiratory compliance, and IAP (bladder pressure) were measured. Abdominal compliance was calculated. Different equations were tested that best described the measured pressure-volume curves. An exponential equation best described the measured pressure-volume curves. Raising IAV increased pP AW and IAP in an exponential manner. Increases in IAP were associated with parallel increases in pP AW with an approximate 40% transmission of IAP to pP AW . The higher the IAP, the greater IAV effected pP AW and IAP. The exponential nature of the effect of IAV on pP AW and IAP implies that, in the presence of high grades of IAH, small reductions in IAV can lead to significant reductions in airway and abdominal pressures. Conversely, in the presence of normal IAP levels, large increases in IAV may not affect airway and abdominal pressures.

Laparoscopic-guided abdominal wall nerve blocks in the pediatric population: a novel technique with comparison to ultrasound-guided blocks and local wound infiltration alone.

PubMed

Landmann, Alessandra; Visoiu, Mihaela; Malek, Marcus M

2018-03-01

Abdominal wall nerve blocks have been gaining popularity for the treatment of perioperative pain in children. Our aim was to compare a technique of surgeon-performed, laparoscopic abdominal wall nerve blocks to anesthesia-placed, ultrasound-guided abdominal wall nerve blocks and the current standard of local wound infiltration. After institutional review board approval was obtained, a retrospective chart review was performed of pediatric patients treated at a single institution during a 2-year period. Statistics were calculated using analysis of variance with post-hoc Bonferonni t tests for pair-wise comparisons. Included in this study were 380 patients who received ultrasound-guided abdominal wall nerve blocks (n = 125), laparoscopic-guided abdominal wall nerve blocks (n = 88), and local wound infiltration (n = 117). Groups were well matched for age, sex, and weight. There was no significant difference in pain scores within the first 8 hours or narcotic usage between groups. Local wound infiltration demonstrated the shortest overall time required to perform (P < .0001). Patients who received a surgeon-performed abdominal wall nerve block demonstrated a shorter duration of hospital stay when compared to the other groups (P = .02). Our study has demonstrated that laparoscopic-guided abdominal wall nerve blocks show similar efficacy to ultrasound-guided nerve blocks performed by pain management physicians without increasing time in the operating room. Copyright © 2017 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, T; Kim, D; Kang, S

Purpose: Abdominal compression is known to be effective but, often makes external-marker-based monitoring of breathing motion not feasible. In this study, we developed and evaluated a system that enables both abdominal compression and monitoring of residual abdominal motion simultaneously. The system can also provide visual-biofeedback capability. Methods: The system developed consists of a compression belt, an abdominal motion monitoring sensor (gas pressure sensor) and a visual biofeedback device. The compression belt was designed to be able to compress the frontal side of the abdomen. The pressure level of the belt is controlled by air volume and monitored in real timemore » using the gas pressure sensor. The system displays not only the real-time monitoring curve but also a guiding respiration model (e.g., a breath hold or shallow breathing curve) simultaneously on the head mounted display to help patients keep their breathing pattern as consistent as possible. Three healthy volunteers were enrolled in this pilot study and respiratory signals (pressure variations) were obtained both with and without effective abdominal compression to investigate the feasibility of the developed system. Two guidance patterns, breath hold and shallow breathing, were tested. Results: All volunteers showed smaller abdominal motion with compression (about 40% amplitude reduction compared to without compression). However, the system was able to monitor residual abdominal motion for all volunteers. Even under abdominal compression, in addition, it was possible to make the subjects successfully follow the guide patterns using the visual biofeedback system. Conclusion: The developed abdominal compression & respiratory guiding system was feasible for residual abdominal motion management. It is considered that the system can be used for a respiratory motion involved radiation therapy while maintaining the merit of abdominal compression. This work was supported by the Radiation Technology R&D program (No. 2013M2A2A7043498) and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the Ministry of Science, ICT&Future Planning.« less

A Novel Diagnostic Aid for Detection of Intra-Abdominal Adhesions to the Anterior Abdominal Wall Using Dynamic Magnetic Resonance Imaging.

PubMed

Randall, David; Fenner, John; Gillott, Richard; Ten Broek, Richard; Strik, Chema; Spencer, Paul; Bardhan, Karna Dev

2016-01-01

Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below. Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images. Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers. Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential.

A Novel Diagnostic Aid for Detection of Intra-Abdominal Adhesions to the Anterior Abdominal Wall Using Dynamic Magnetic Resonance Imaging

PubMed Central

Randall, David; Fenner, John; Gillott, Richard; ten Broek, Richard; Strik, Chema; Spencer, Paul; Bardhan, Karna Dev

2016-01-01

Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below. Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images. Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers. Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential. PMID:26880884

Evaluation of optical data gained by ARAMIS-measurement of abdominal wall movements for an anisotropic pattern design of stress-adapted hernia meshes produced by embroidery technology

NASA Astrophysics Data System (ADS)

Breier, A.; Bittrich, L.; Hahn, J.; Spickenheuer, A.

2017-10-01

For the sustainable repair of abdominal wall hernia the application of hernia meshes is required. One reason for the relapse of hernia after surgery is seen in an inadequate adaption of the mechanical properties of the mesh to the movements of the abdominal wall. Differences in the stiffness of the mesh and the abdominal tissue cause tension, friction and stress resulting in a deficient tissue response and subsequently in a recurrence of a hernia, preferentially in the marginal area of the mesh. Embroidery technology enables a targeted influence on the mechanical properties of the generated textile structure by a directed thread deposition. Textile parameters like stitch density, alignment and angle can be changed easily and locally in the embroidery pattern to generate a space-resolved mesh with mechanical properties adapted to the requirement of the surrounding tissue. To determine those requirements the movements of the abdominal wall and the resulting distortions need to be known. This study was conducted to gain optical data of the abdominal wall movements by non-invasive ARAMIS-measurement on 39 test persons to estimate direction and value of the major strains.

Blast Trauma. The Effect on Hearing.

DTIC Science & Technology

1983-07-01

Reissner’ s menbrane was also removed. £he re-arning cochlea was then rapidly dehydrated in a cold graded ETOH series (50, 70, 80, 95, 100%). The... plasma zpze aet,’,r the eIBCs and the vessel wall. This could be interpreted as the r ’Lt of vessel constriction, of corpuscular rather than laminar blood...most likely explanation for the de.crease in plasma spuc-e. Constrictions and irregularities of the vessel lumen appear to be due to an increased

Pseudomyopia in a patient with blocked ventriculo-peritoneal shunt--a case report.

PubMed

Voon, L W; Goh, K Y; Lim, T H; Tan, K K; Yong, V S

1997-03-01

Accommodative spasm usually encompasses a classical triad of pseudomyopia, esodeviation and pupillary constriction. Accommodative spasm is most often psychogenic in nature; however, it may be associated with other organic diseases of which a rare cause is that of intracranial catheter complications. We report a case of dorsal midbrain syndrome with pseudomyopia in a patient with a blocked ventriculo-peritoneal shunt inserted for aqueductal stenosis. Clinical presentation was unusual in this patient as pseudomyopia occurred with exodeviation and without pupillary constriction.

The constricted ear.

PubMed

Paredes, Alfredo A; Williams, J Kerwin; Elsahy, Nabil I

2002-04-01

The constricted ear may be described best as a pursestring closure of the ear. The deformity may include lidding of the upper pole with downward folding, protrusion of the concha, decreased vertical height, and low ear position relative to the face. The goals of surgical correction should include obtaining symmetry and correcting the intra-auricular anatomy. The degree of intervention is based on the severity of the deformity and may range from simple repositioning, soft tissue rearrangement, or manipulation of the cartilage. Multiple surgical techniques are described.

Evaluation of aqueous and ethanolic extracts of saffron, Crocus sativus L., and its constituents, safranal and crocin in allodynia and hyperalgesia induced by chronic constriction injury model of neuropathic pain in rats.

PubMed

Amin, Bahareh; Hosseinzadeh, Hossein

2012-07-01

The current study was designed to evaluate therapeutic potential of systemically administered ethanolic and aqueous extracts of saffron as well as its bioactive ingredients, safranal and crocin, in chronic constriction injury (CCI)-induced neuropathic pain in rats. The von Frey filaments, acetone drop, and radiant heat test were performed to assess the degree of mechanical allodynia, thermal allodynia and thermal hyperalgesia respectively, at different time intervals, i.e., one day before surgery and 3, 5, 7 and 10 days post surgery. The ambulatory behavior was evaluated using the open field test. A 7-day treatment with the ethanolic and aqueous extracts (50,100 and 200 mg/kg, i.p.) and safranal (0.025, 0.05 and 0.1 mg/kg, i.p.), attenuated the behavioral symptoms of neuropathic pain in a dose dependent manner. Crocin even at the high dose (50 mg/kg) failed to produce any protective role. However, gabapentine (100 mg/kg) as a reference drug significantly alleviated all behavioral manifestations of neuropathic pain compared to control group. In conclusion, the results of this study suggest that ethanolic and aqueous extracts of saffron as well as safranal could be useful in treatment of different kinds of neuropathic pains and as an adjuvant to conventional medicines. Copyright © 2012 Elsevier B.V. All rights reserved.

An abdominal active can defibrillator may facilitate a successful generator change when a lead failure is present.

PubMed

Solomon, A J; Moubarak, J B; Drood, J M; Tracy, C M; Karasik, P E

1999-10-01

Defibrillator generator changes are frequently performed on patients with an implantable cardioverter defibrillator in an abdominal pocket. These patients usually have epicardial patches or older endocardial lead systems. At the time of a defibrillator generator change defibrillation may be unsuccessful as a result of lead failure. We tested the hypothesis that an active can defibrillator implanted in the abdominal pocket could replace a non-functioning endocardial lead or epicardial patch. An abdominal defibrillator generator change was performed in 10 patients, (mean age = 67 +/- 13 years, nine men). Initially, a defibrillation threshold (DFT) was obtained using a passive defibrillator and the chronic endocardial or epicardial lead system. DFTs were then performed using an active can emulator and one chronic lead to simulate endocardial or epicardial lead failure. We tested 30 lead configurations (nine endocardial and 21 epicardial). Although a DFT of 7.3 +/- 4.2 joules was obtained with the intact chronic lead system, the active can emulator and one endocardial or epicardial lead still yielded an acceptable DFT of 19.9 +/- 6.1 joules. In addition, a successful implant (DFT < or = 24 joules) could have been accomplished in 28 of 30 (93%) lead configurations. An active can defibrillator in an abdominal pocket may allow for a successful generator change in patients with defibrillator lead malfunction. This would be simpler than abandoning the abdominal implant and moving to a new pectoral device and lead or tunnelling a new endocardial electrode. However, loss of defibrillation capability with a particular complex lead may be a warning of impending loss of other functions (eg. sensing and/or pacing).

Randomized trial of amino acid mixture combined with physical activity promotion for abdominal fat reduction in overweight adults.

PubMed

Ueda, Keisuke; Sasai, Hiroyuki; Tsujimoto, Takehiko; Sanbongi, Chiaki; Ikegami, Shuji; Kobayashi, Hiroyuki; Shioya, Nobuhiko; Suzuki, Satoru; Nakata, Yoshio

2018-01-01

The purpose of this study was to test the efficacy of arginine, alanine, and phenylalanine mixture (A-mix) ingestion at 1,500 mg/day in combination with the promotion of physical activity for abdominal fat reduction in overweight adults. A placebo-controlled, double-blind, parallel-group, randomized trial for 12 weeks combined with a 4-week follow-up period was conducted at a single center in Minato-ku, Tokyo, Japan, between December 2016 and May 2017. Data were analyzed between June and August 2017. The study participants were 200 overweight adults within the age range of 20-64 years. The participants were randomly assigned to the A-mix group (n=100) or a placebo group (n=100) and were administered 500 mL of test beverage containing 1,500 or 0 mg of A-mix, respectively, for 12 weeks. All participants maintained a physically active lifestyle between week 0 and week 12 through monthly sessions of physical activity. The primary outcomes were the 12-week changes in the abdominal total, subcutaneous, and visceral fat areas, as assessed by computed tomography. Of the 200 enrolled participants, 199 (99%) accomplished the 12-week intervention and 4-week follow-up period. The per-protocol-based analysis for 194 participants demonstrated that the abdominal total fat area decreased significantly in the A-mix group compared with that in the placebo group (difference, 10.0 cm 2 ; 95% confidence interval [CI]: 0.4-19.6 cm 2 ; P =0.041). Comparable outcomes were obtained for the abdominal subcutaneous fat area (difference, 7.4 cm 2 ; 95% CI: 0.1-14.7 cm 2 ; P =0.047). No study-related unfavorable events occurred. A-mix supplementation in combination with physical activity promotion facilitated abdominal fat reduction in overweight adults.

Towards the mechanical characterization of abdominal wall by inverse analysis.

PubMed

Simón-Allué, R; Calvo, B; Oberai, A A; Barbone, P E

2017-02-01

The aim of this study is to characterize the passive mechanical behaviour of abdominal wall in vivo in an animal model using only external cameras and numerical analysis. The main objective lies in defining a methodology that provides in vivo information of a specific patient without altering mechanical properties. It is demonstrated in the mechanical study of abdomen for hernia purposes. Mechanical tests consisted on pneumoperitoneum tests performed on New Zealand rabbits, where inner pressure was varied from 0mmHg to 12mmHg. Changes in the external abdominal surface were recorded and several points were tracked. Based on their coordinates we reconstructed a 3D finite element model of the abdominal wall, considering an incompressible hyperelastic material model defined by two parameters. The spatial distributions of these parameters (shear modulus and non linear parameter) were calculated by inverse analysis, using two different types of regularization: Total Variation Diminishing (TVD) and Tikhonov (H 1 ). After solving the inverse problem, the distribution of the material parameters were obtained along the abdominal surface. Accuracy of the results was evaluated for the last level of pressure. Results revealed a higher value of the shear modulus in a wide stripe along the craneo-caudal direction, associated with the presence of linea alba in conjunction with fascias and rectus abdominis. Non linear parameter distribution was smoother and the location of higher values varied with the regularization type. Both regularizations proved to yield in an accurate predicted displacement field, but H 1 obtained a smoother material parameter distribution while TVD included some discontinuities. The methodology here presented was able to characterize in vivo the passive non linear mechanical response of the abdominal wall. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transvesical Intra-Abdominal Pressure Measurement in Newborn: What Is the Optimal Saline Volume Instillation?

PubMed

Defontaine, Anne; Tirel, Olivier; Costet, Nathalie; Beuchée, Alain; Ozanne, Bruno; Gaillot, Théophile; Arnaud, Alexis Pierre; Wodey, Eric

2016-02-01

To determine the optimal saline volume bladder instillation to measure intravesical pressure in critically ill newborns weighing less than 4.5 kg, and to establish a reference of intra-abdominal pressure value in this population. Prospective monocentric study. Neonatal ICU and PICU. Newborns, premature or not, weighing less than 4.5 kg who required a urethral catheter. Patients were classified into two groups according to whether they presented a risk factor for intra-abdominal hypertension. Nine intravesical pressure measures per patient were performed after different volume saline instillation. The first one was done without saline instillation and then by increments of 0.5 mL/kg to a maximum of 4 mL/kg. Linear models for repeated measurements of intravesical pressure with unstructured covariance were used to analyze the variation of intravesical pressure measures according to the conditions of measurement (volume instilled). Pairwise comparisons of intravesical pressure adjusted mean values between instillation volumes were done using Tukey tests, corrected for multiple testing to determine an optimal instillation volume. Forty-seven patients with completed measures (nine instillations volumes) were included in the analysis. Mean intravesical pressure values were not significantly different when measured after instillation of 0.5, 1, or 1.5 mL/kg, whereas measures after instillation of 2 mL/kg or more were significantly higher. The median intravesical pressure value in the group without intra-abdominal hypertension risk factor after instillation of 1 mL/kg was 5 mm Hg (2-6 mm Hg). The optimal saline volume bladder instillation to measure intra-abdominal pressure in newborns weighing less than 4.5 kg was 1 mL/kg. Reference intra-abdominal pressure in this population was found to be 5 mm Hg (2-6 mm Hg).

Bilateral sertoli and interstitial cell tumours in abdominal testes of a goat with polled intersex syndrome (PIS).

PubMed

Canisso, I F; Coffee, L L; Ortved, K; Fubini, S L; Monteagudo, L V; Schlafer, D H; Gilbert, R O

2014-12-01

An 8-year-old, mixed breed, polled goat was presented for evaluation of male-like behaviour. Clinical findings included clitoromegaly, a heavily muscled neck, pronounced beard, and erect dorsal guard hairs, which are phenotypic characteristics commonly observed in intersex animals. Transrectal ultrasonography revealed the presence of two abdominal masses caudolateral to the uterine horns. Serum concentration of estradiol was elevated. Genetic evaluation was compatible with polled intersex syndrome defined by an XX karyotype without a Y chromosome or SRY gene. Based on gross and histologic evaluation, the abdominal masses were determined to be intra-abdominal testes, each of which was effaced by Sertoli cell and interstitial (Leydig) cell tumours. The Sertoli cell tumours (SCTs) represented two unique histologic patterns. Regardless of pattern, neoplastic Sertoli cells were consistently lipid laden and positive for vimentin. Interstitial cell tumours (ICTs) were negative for vimentin. Clinical and histopathologic findings suggest that prolonged exposure to steroids secreted by neoplastic Sertoli cells contributed to virilization. In addition, results from immunohistochemistry indicated that vimentin may be a valuable immunodiagnostic tool for differentiation between interstitial and Sertoli cell tumours in goats. © 2014 Blackwell Verlag GmbH.

Is routine pregnancy test necessary in women of reproductive age admitted to the emergency department?

PubMed

Köksal, Ozlem; Ozdemir, Fatma; Armağan, Erol; Oner, Nuran; Sert, Pınar Çinar; Sigirli, Deniz

2013-01-01

This study aimed to determine the necessity of pregnancy test in women of reproductive age admitted to emergency department (ED) in routine practice. We retrospectively reviewed the records of patients who presented to the ED between January 1, 2006 and December 31, 2010 and received a pregnancy test. The median age of 1 586 patients enrolled into the study was 27 years. Of these patients, 19.55% had a positive result of pregnancy test. The most common complaint at admission was abdominal pain in 60.15% of the patients, and pregnancy test was prescribed. 15.83% of the patients with abdominal pain had a positive result of pregnancy test. Of the patients, 30.64% had nausea-vomiting at admission, and 11.52% had a positive result of pregnancy test. When other complaints were considered, the most commonly observed complaints were non-specific symptoms such as dizziness, malaise and respiratory problems. Of the patients, 70.93% were not remembering the date of last menstruation, and 9.51% showed a positive result of pregnancy test. Urinary tract infection (UTI) was commonly diagnosed with an incidence of 17.65%, which was followed by non-specific abdominal pain (NSAP) (16.77%) and gastrointestinal disorders such as gastritis and peptic ulcer (6.87%). Of the patients, 88.40% were discharged from ED, and 11.60% were hospitalized. Pregnancy test should be given to women of reproductive age as a routine practice in ED in developing countries like Turkey.

[Undifferentiated (embryonal) sarcoma of the liver. Report of a case].

PubMed

Orozco, H; Mercado, M A; Takahashi, T; Chan, C; Quintanilla, L; Jiménez, M; Sosa, R; Esquivel, E

1991-01-01

A 15-year-old woman who was studied because an abdominal mass at the Instituto Nacional de la Nutricion Salvador Zubiran (INNSZ) is reported. The history revealed only malaise and mild abdominal pain. At physical exploration, an abdominal mass in the upper right quadrant was found. Liver function tests were normal. Abdominal ultrasound and computerized tomography revealed a large cystic mass of the right hepatic lobe. She underwent exploratory laparotomy. Intraoperative frozen sections of the biopsies demonstrated undifferentiated sarcoma of the liver, and an extended right trisegmentectomy was performed. Postoperative outcome was uneventful. Adjuvant treatment with doxorubicin and dacarbazine was given, and at six months of follow-up, the patient is alive without any evidence of recurrence. Clinical and histopathologic features of this rare malignant tumor are discussed, as well as the therapeutic choices.

Relationships of abdominal pain, reports to visceral and temperature pain sensitivity, conditioned pain modulation, and heart rate variability in irritable bowel syndrome.

PubMed

Jarrett, M E; Han, C J; Cain, K C; Burr, R L; Shulman, R J; Barney, P G; Naliboff, B D; Zia, J; Heitkemper, M M

2016-07-01

Irritable bowel syndrome (IBS) is a heterogeneous condition with a number of pathophysiological mechanisms that appear to contribute to symptom chronicity. One of these is altered pain sensitivity. Women between ages 18-45 were recruited the community. Of those enrolled, 56 had IBS and 36 were healthy control (HC) women. Participants completed questionnaires, kept a 4-week symptom diary and had a 12-h Holter placed to assess nighttime heart rate variability including high frequency power (HF), low frequency power (LF), and total power (TP). At mid-follicular phase approximately 80% of women completed a thermal pain sensitivity test with conditioned pain modulation and visceral pain sensitivity using a water load symptom provocation (WLSP) test. As expected, daily abdominal pain was significantly higher in the IBS compared to HC group. There were no differences between the bowel pattern subgroups (IBS-diarrhea [IBS-D], IBS-constipation plus mixed [IBS-CM]). Thermal pain sensitivity did not differ between the IBS and the HC groups, but was significantly higher in the IBS-CM group than the IBS-D group. In the WLSP test, the IBS group experienced significantly more symptom distress than HCs and the IBS-CM group was higher than the IBS-D group. Heart rate variability indicators did not differ between the groups or IBS subgroups. Daily abdominal pain was positively correlated with LF and TP in the IBS group. Despite similar levels of abdominal pain in IBS, the IBS-CM group demonstrated greater sensitivity to both thermal and visceral testing procedures. © 2016 John Wiley & Sons Ltd.

Can a pilates exercise program be effective on balance, flexibility and muscle endurance? A randomized controlled trial.

PubMed

Kibar, Sibel; Yardimci, Fatma Ö; Evcik, Deniz; Ay, Saime; Alhan, Aslıhan; Manço, Miray; Ergin, Emine S

2016-10-01

This randomized controlled study aims to determine the effect of pilates mat exercises on dynamic and static balance, hamstring flexibility, abdominal muscle activity and endurance in healthy adults. Female healthy volunteer university students randomly assigned into two groups. Group 1 followed a pilates program for an hour two times a week. Group 2 continued daily activities as control group. Dynamic and static balance were evaluated by Sport Kinesthetic Ability Trainer (KAT) 4000 device. Hamstring flexibility and abdominal endurance were determined by sit-and-reach test, curl-up test respectively. Pressure biofeedback unit (PBU) was used to measure transversus abdominis and lumbar muscle activity. The physical activity of the participants was followed by International Physical Activity Questionnaire-Short Form. Twenty-three subjects in pilates group and 24 control subjects completed the study. In pilates group, statistical significant improvements were observed in curl-up, sit-and-reach test, PBU scores at sixth week (P<0.001), and KAT static and dynamic balance scores (P<0.001), waist circumference (P=0.007) at eighth week. In the comparison between two groups, there were significant improvements in pilates group for sit-and-reach test (P=0.01) and PBU scores (P<0.001) at sixth week, additionally curl-up and static KAT scores progressed in eighth week (P<0.001). No correlation was found between flexibility, endurance, trunk muscle activity and balance parameters. An eight-week pilates training program has been found to have beneficial effect on static balance, flexibility, abdominal muscle endurance, abdominal and lumbar muscle activity. These parameters have no effect on balance.

A Study of Physicochemical Properties of Subcutaneous Fat of the Abdomen and its Implication in Abdominal Obesity.

PubMed

Pandey, Arvind Kumar; Kumar, Pramod; Kodavoor, Srinivas Aithal; Kotian, Sushma Rama; Yathdaka, Sudhakar Narahari; Nayak, Dayanand; Souza, Anne D; Souza, Antony Sylvan D

2016-05-01

The lower abdominal obesity is more resistant to absorption as compared to that of upper abdomen. Differences in the physicochemical properties of the subcutaneous fat of the upper and lower abdomen may be responsible for this variation. There is paucity of the scientific literature on the physicochemical properties of the subcutaneous fat of abdomen. The present study was undertaken to create a database of physicochemical properties of abdominal subcutaneous fat. The samples of subcutaneous fat from upper and lower abdomen were collected from 40 fresh autopsied bodies (males 33, females 7). The samples were prepared for physicochemical analysis using organic and inorganic solvents. Various physicochemical properties of the fat samples analysed were surface tension, viscosity, specific gravity, specific conductivity, iodine value and thermal properties. Data was analysed by paired and independent sample t-tests. There was a statistically significant difference in all the physicochemical parameters between males and females except surface tension (organic) and surface tension (inorganic) of upper abdominal fat, and surface tension (organic) of lower abdominal fat. In males, viscosity of upper abdominal fat was more compared to that of lower abdomen (both organic and inorganic) unlike the specific conductivity that was higher for the lower abdominal fat as compared to that of the upper abdomen. In females there were statistically significant higher values of surface tension (inorganic) and specific gravity (organic) of the upper abdomen fat as compared to that of lower abdomen. The initial and final weight loss of the lower abdominal fat as indicated by Thermo Gravimetric Analysis was significantly more in males than in female. The difference in the physicochemical properties of subcutaneous fat between upper and lower abdomen and between males and females could be responsible for the variant behaviour of subcutaneous abdominal fat towards resorption.

Hyperandrogenism Accompanies Increased Intra-Abdominal Fat Storage in Normal Weight Polycystic Ovary Syndrome Women

PubMed Central

Akopians, Alin L.; Madrigal, Vanessa K.; Ramirez, Emmanuel; Margolis, Daniel J.; Sarma, Manoj K.; Thomas, Albert M.; Grogan, Tristan R.; Haykal, Rasha; Schooler, Tery A.; Okeya, Bette L.; Abbott, David H.; Chazenbalk, Gregorio D.

2016-01-01

Context: Normal weight polycystic ovary syndrome (PCOS) women may have altered adipose structure-function underlying metabolic dysfunction. Objective: This study examines whether adipose structure-functional changes exist in normal weight PCOS women and correlate with hyperandrogenism and/or hyperinsulinemia. Design: This is a prospective cohort study. Setting: The setting was an academic medical center. Patients: Six normal weight PCOS women and 14 age- and body mass index-matched normoandrogenic ovulatory (NL) women were included. Intervention(s): All women underwent circulating hormone and metabolic measurements; frequently sampled intravenous glucose tolerance testing; total body dual-energy x-ray absorptiometry; abdominal magnetic resonance imaging; and SC abdominal fat biopsy. Main Outcome Measure(s): Circulating hormones and metabolites, body fat and its distribution, and adipocyte size were compared between PCOS and NL women, and were correlated with each other in all women. Results: Circulating LH and androgen levels were significantly greater in PCOS than NL women, as were fasting insulin levels, pancreatic β-cell responsiveness to glucose, and total abdominal fat mass. Intra-abdominal fat mass also was significantly increased in PCOS women and was positively correlated with circulating androgen, fasting insulin, triglyceride, and non-high-density lipoprotein cholesterol levels in all women. SC abdominal fat mass was not significantly increased in PCOS women, but contained a greater proportion of small SC abdominal adipocytes that positively correlated with serum androgen levels in all women. Conclusion: Hyperandrogenism in normal weight PCOS women is associated with preferential intra-abdominal fat deposition and an increased population of small SC abdominal adipocytes that could constrain SC adipose storage and promote metabolic dysfunction. PMID:27571186

Predictors of Abdominal Pain in Depressed Pediatric Inflammatory Bowel Disease Patients

PubMed Central

Srinath, Arvind I.; Goyal, Alka; Zimmerman, Lori A.; Newara, Melissa C.; Kirshner, Margaret A.; McCarthy, F. Nicole; Keljo, David; Binion, David; Bousvaros, Athos; DeMaso, David R.; Youk, Ada; Szigethy, Eva M.

2015-01-01

Background Pediatric patients with inflammatory bowel disease (IBD) have high rates of abdominal pain. The study aims were to (1) Evaluate biological and psychological correlates of abdominal pain in depressed youth with IBD, (2) Determine predictors of abdominal pain in Crohn’s disease (CD) and ulcerative colitis (UC). Methods 765 patients ages 9–17 with IBD seen over 3 years at two sites were screened for depression. Depressed youth completed comprehensive assessments for abdominal pain, psychological (depression and anxiety), and biological (IBD-related, through disease activity indices and laboratory values) realms. Results 217 patients with IBD (161 CD, 56 UC) were depressed. 163 (120 CD, 43 UC) patients had complete API scores. In CD, abdominal pain was associated with depression (r=0.33; p<0.001), diarrhea (r=0.34; p=0.001), ESR (r=0.22; p=0.02), low albumin (r=0.24; p=.01), weight loss (r=0.33; p=0.001), and abdominal tenderness (r=0.38, p=0.002). A multivariate model with these significant correlates represented 32% of the variance in pain. Only depression (p=0.03), weight loss (p=0.04), and abdominal tenderness (p=0.01) predicted pain for CD patients. In UC, pain was associated with depression (r=0.46; p=0.002) and nocturnal stools (r=.32; p=.046). In the multivariate model with these significant correlates 23% of the variance was explained, and only depression (p=0.02) predicted pain. Conclusions The psychological state of pediatric patients with IBD may increase the sensitivity to abdominal pain. Thus, screening for and treating comorbid depression may prevent excessive medical testing and unnecessary escalation of IBD medications. PMID:24983975

Electrode support for gas arc welding torch having coaxial vision

NASA Technical Reports Server (NTRS)

Richardson, Richard W. (Inventor)

1987-01-01

An improved electrode mounting structure for a gas tungsten arc welding torch having a coaxial imaging system. The electrode mounting structure includes a support having a central hub and a plurality of spokes which extend from the hub generally radially with respect to the axis of the torch into supporting engagement with the interior walls of the torch. The spaces between the spokes are optical passages for transmission of light to form the image. A tubular collet holder is threadedly engaged at its upper end to the hub and extends downwardly toward the open end of the torch. The collet holder has an inwardly tapering constriction near its lower end. An electrode-retaining, tubular collet is mounted within the collet holder and has a longitudinally split and tapered end seating against the tapered constriction. A spring seats against the upper end of the collet and forces the split end against the tapered constriction to wedge the split end radially inwardly to grip the electrode within the collet.

Loss of Gα12/13 exacerbates apical area dependence of actomyosin contractility

PubMed Central

Xie, Shicong; Mason, Frank M.; Martin, Adam C.

2016-01-01

During development, coordinated cell shape changes alter tissue shape. In the Drosophila ventral furrow and other epithelia, apical constriction of hundreds of epithelial cells folds the tissue. Genes in the Gα12/13 pathway coordinate collective apical constriction, but the mechanism of coordination is poorly understood. Coupling live-cell imaging with a computational approach to identify contractile events, we discovered that differences in constriction behavior are biased by initial cell shape. Disrupting Gα12/13 exacerbates this relationship. Larger apical area is associated with delayed initiation of contractile pulses, lower apical E-cadherin and F-actin levels, and aberrantly mobile Rho-kinase structures. Our results suggest that loss of Gα12/13 disrupts apical actin cortex organization and pulse initiation in a size-dependent manner. We propose that Gα12/13 robustly organizes the apical cortex despite variation in apical area to ensure the timely initiation of contractile pulses in a tissue with heterogeneity in starting cell shape. PMID:27489340

Pediatric constrictive asphyxia a rare form of child abuse: A report of two cases.

PubMed

Vester, M E M; Bilo, R A C; Nijs, H G T; van Rijn, R R

2018-04-01

We present two cases of infants who died under suspicious circumstances. After clinical and legal investigations, non-accidental constrictive asphyxia inflicted by one of the parents was established. The first case presents a to date not yet reported, unique mechanism of trauma. In order to stop his daughter from crying, the father admitted that he sometimes sat on his baby while she was lying on the bed. Occasionally increasing his force by pulling with his hands on the bottom of the bed. In the second case tight swaddling and encircling chest compression was the causative mechanism. In both cases the father was sentenced to imprisonment with mandate psychiatric care. Only two previous reports of this uncommon and relatively unknown cause of child abuse, called constrictive asphyxia, are known. In all reported cases static loading of the chest resulted in rib fractures and demise of the child. This rare abusive mechanism should be known to pediatric radiologists and pathologists. Copyright © 2018 Elsevier B.V. All rights reserved.

Phase transition solutions in geometrically constrained magnetic domain wall models

NASA Astrophysics Data System (ADS)

Chen, Shouxin; Yang, Yisong

2010-02-01

Recent work on magnetic phase transition in nanoscale systems indicates that new physical phenomena, in particular, the Bloch wall width narrowing, arise as a consequence of geometrical confinement of magnetization and leads to the introduction of geometrically constrained domain wall models. In this paper, we present a systematic mathematical analysis on the existence of the solutions of the basic governing equations in such domain wall models. We show that, when the cross section of the geometric constriction is a simple step function, the solutions may be obtained by minimizing the domain wall energy over the constriction and solving the Bogomol'nyi equation outside the constriction. When the cross section and potential density are both even, we establish the existence of an odd domain wall solution realizing the phase transition process between two adjacent domain phases. When the cross section satisfies a certain integrability condition, we prove that a domain wall solution always exists which links two arbitrarily designated domain phases.

Constriction of the mitochondrial inner compartment is a priming event for mitochondrial division

PubMed Central

Cho, Bongki; Cho, Hyo Min; Jo, Youhwa; Kim, Hee Dae; Song, Myungjae; Moon, Cheil; Kim, Hyongbum; Kim, Kyungjin; Sesaki, Hiromi; Rhyu, Im Joo; Kim, Hyun; Sun, Woong

2017-01-01

Mitochondrial division is critical for the maintenance and regulation of mitochondrial function, quality and distribution. This process is controlled by cytosolic actin-based constriction machinery and dynamin-related protein 1 (Drp1) on mitochondrial outer membrane (OMM). Although mitochondrial physiology, including oxidative phosphorylation, is also important for efficient mitochondrial division, morphological alterations of the mitochondrial inner-membrane (IMM) have not been clearly elucidated. Here we report spontaneous and repetitive constriction of mitochondrial inner compartment (CoMIC) associated with subsequent division in neurons. Although CoMIC is potentiated by inhibition of Drp1 and occurs at the potential division spots contacting the endoplasmic reticulum, it appears on IMM independently of OMM. Intra-mitochondrial influx of Ca2+ induces and potentiates CoMIC, and leads to K+-mediated mitochondrial bulging and depolarization. Synergistically, optic atrophy 1 (Opa1) also regulates CoMIC via controlling Mic60-mediated OMM–IMM tethering. Therefore, we propose that CoMIC is a priming event for efficient mitochondrial division. PMID:28598422

Cylindrical cellular geometry ensures fidelity of division site placement in fission yeast.

PubMed

Mishra, Mithilesh; Huang, Yinyi; Srivastava, Pragya; Srinivasan, Ramanujam; Sevugan, Mayalagu; Shlomovitz, Roie; Gov, Nir; Rao, Madan; Balasubramanian, Mohan

2012-08-15

Successful cytokinesis requires proper assembly of the contractile actomyosin ring, its stable positioning on the cell surface and proper constriction. Over the years, many of the key molecular components and regulators of the assembly and positioning of the actomyosin ring have been elucidated. Here we show that cell geometry and mechanics play a crucial role in the stable positioning and uniform constriction of the contractile ring. Contractile rings that assemble in locally spherical regions of cells are unstable and slip towards the poles. By contrast, actomyosin rings that assemble on locally cylindrical portions of the cell under the same conditions do not slip, but uniformly constrict the cell surface. The stability of the rings and the dynamics of ring slippage can be described by a simple mechanical model. Using fluorescence imaging, we verify some of the quantitative predictions of the model. Our study reveals an intimate interplay between geometry and actomyosin dynamics, which are likely to apply in a variety of cellular contexts.

Tunable transmission of quantum Hall edge channels with full degeneracy lifting in split-gated graphene devices.

PubMed

Zimmermann, Katrin; Jordan, Anna; Gay, Frédéric; Watanabe, Kenji; Taniguchi, Takashi; Han, Zheng; Bouchiat, Vincent; Sellier, Hermann; Sacépé, Benjamin

2017-04-13

Charge carriers in the quantum Hall regime propagate via one-dimensional conducting channels that form along the edges of a two-dimensional electron gas. Controlling their transmission through a gate-tunable constriction, also called quantum point contact, is fundamental for many coherent transport experiments. However, in graphene, tailoring a constriction with electrostatic gates remains challenging due to the formation of p-n junctions below gate electrodes along which electron and hole edge channels co-propagate and mix, short circuiting the constriction. Here we show that this electron-hole mixing is drastically reduced in high-mobility graphene van der Waals heterostructures thanks to the full degeneracy lifting of the Landau levels, enabling quantum point contact operation with full channel pinch-off. We demonstrate gate-tunable selective transmission of integer and fractional quantum Hall edge channels through the quantum point contact. This gate control of edge channels opens the door to quantum Hall interferometry and electron quantum optics experiments in the integer and fractional quantum Hall regimes of graphene.

Experimental observation of edge transport in graphene nanostructures

NASA Astrophysics Data System (ADS)

Kinikar, Amogh; Sai, T. Phanindra; Bhattacharyya, Semonti; Agarwala, Adhip; Biswas, Tathagata; Sarker, Sanjoy K.; Krishnamurthy, H. R.; Jain, Manish; Shenoy, Vijay B.; Ghosh, Arindam

The zizzag edges of graphene, whether single or few layers, host zero energy gapless states and are perfect 1D ballistic conductors. Conclusive observations of electrical conduction through edge states has been elusive. We report the observation of edge bound transport in atomic-scale constrictions of single and multilayer suspended graphene created stochastically by nanomechanical exfoliation of graphite. We observe that the conductance is quantized in near multiples of e2/h. Non-equilibrium transport shows a split zero bias anomaly and, the magneto-conductance is hysteretic; indicating that the electron transport is through spin polarized edge states in the presence of electron-electron interaction. Atomic force microscope scans on the graphite surface post exfoliation reveal that the final constriction is usually a single layer graphene with a constricting angle of 30o. Tearing along crystallographic angles suggests the tears occur along zigzag and armchair configurations with high fidelity of the edge morphology. We acknowledge the financial support from the DST, Government of India. SS acknowledges support from the NSF (DMR-1508680).

Fluid sampling system

DOEpatents

Houck, Edward D.

1994-01-01

An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank.

Fluid sampling system

DOEpatents

Houck, E.D.

1994-10-11

An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to be decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank. 4 figs.

Improved Fuzzy K-Nearest Neighbor Using Modified Particle Swarm Optimization

NASA Astrophysics Data System (ADS)

Jamaluddin; Siringoringo, Rimbun

2017-12-01

Fuzzy k-Nearest Neighbor (FkNN) is one of the most powerful classification methods. The presence of fuzzy concepts in this method successfully improves its performance on almost all classification issues. The main drawbackof FKNN is that it is difficult to determine the parameters. These parameters are the number of neighbors (k) and fuzzy strength (m). Both parameters are very sensitive. This makes it difficult to determine the values of ‘m’ and ‘k’, thus making FKNN difficult to control because no theories or guides can deduce how proper ‘m’ and ‘k’ should be. This study uses Modified Particle Swarm Optimization (MPSO) to determine the best value of ‘k’ and ‘m’. MPSO is focused on the Constriction Factor Method. Constriction Factor Method is an improvement of PSO in order to avoid local circumstances optima. The model proposed in this study was tested on the German Credit Dataset. The test of the data/The data test has been standardized by UCI Machine Learning Repository which is widely applied to classification problems. The application of MPSO to the determination of FKNN parameters is expected to increase the value of classification performance. Based on the experiments that have been done indicating that the model offered in this research results in a better classification performance compared to the Fk-NN model only. The model offered in this study has an accuracy rate of 81%, while. With using Fk-NN model, it has the accuracy of 70%. At the end is done comparison of research model superiority with 2 other classification models;such as Naive Bayes and Decision Tree. This research model has a better performance level, where Naive Bayes has accuracy 75%, and the decision tree model has 70%

Mycobacteriosis in a domestic ferret (Mustela putorius furo).

PubMed

Nakata, Makoto; Miwa, Yasutsugu; Tsuboi, Masaya; Uchida, Kazuyuki

2014-05-01

A 4-year-old spayed female ferret presented with a 2-month history of anorexia, vomiting and occasional diarrhea. Abdominal ultrasonography revealed thickening of the gastric wall and enlarged abdominal lymph nodes. Biopsy samples from the thickened gastric wall, enlarged abdominal lymph nodes and liver were taken during an exploratory laparotomy. Based on the histopathological examination, mycobacterium infection was diagnosed. The bacterial species could not be identified by additional diagnostic tests of feces, including fecal smear, culture and polymerase chain reaction (PCR). The ferret was treated with prednisolone and multiple antimicrobials, including rifampicin, azithromycin and enrofloxacin, but did not improve with treatment and died 220 days after the first presentation.

Local small airway epithelial injury induces global smooth muscle contraction and airway constriction

PubMed Central

Zhou, Jian; Alvarez-Elizondo, Martha B.; Botvinick, Elliot

2012-01-01

Small airway epithelial cells form a continuous sheet lining the conducting airways, which serves many functions including a physical barrier to protect the underlying tissue. In asthma, injury to epithelial cells can occur during bronchoconstriction, which may exacerbate airway hyperreactivity. To investigate the role of epithelial cell rupture in airway constriction, laser ablation was used to precisely rupture individual airway epithelial cells of small airways (<300-μm diameter) in rat lung slices (∼250-μm thick). Laser ablation of single epithelial cells using a femtosecond laser reproducibly induced airway contraction to ∼70% of the original cross-sectional area within several seconds, and the contraction lasted for up to 40 s. The airway constriction could be mimicked by mechanical rupture of a single epithelial cell using a sharp glass micropipette but not with a blunt glass pipette. These results suggest that soluble mediators released from the wounded epithelial cell induce global airway contraction. To confirm this hypothesis, the lysate of primary human small airway epithelial cells stimulated a similar airway contraction. Laser ablation of single epithelial cells triggered a single instantaneous Ca2+ wave in the epithelium, and multiple Ca2+ waves in smooth muscle cells, which were delayed by several seconds. Removal of extracellular Ca2+ or decreasing intracellular Ca2+ both blocked laser-induced airway contraction. We conclude that local epithelial cell rupture induces rapid and global airway constriction through release of soluble mediators and subsequent Ca2+-dependent smooth muscle shortening. PMID:22114176

Local small airway epithelial injury induces global smooth muscle contraction and airway constriction.

PubMed

Zhou, Jian; Alvarez-Elizondo, Martha B; Botvinick, Elliot; George, Steven C

2012-02-01

Small airway epithelial cells form a continuous sheet lining the conducting airways, which serves many functions including a physical barrier to protect the underlying tissue. In asthma, injury to epithelial cells can occur during bronchoconstriction, which may exacerbate airway hyperreactivity. To investigate the role of epithelial cell rupture in airway constriction, laser ablation was used to precisely rupture individual airway epithelial cells of small airways (<300-μm diameter) in rat lung slices (∼250-μm thick). Laser ablation of single epithelial cells using a femtosecond laser reproducibly induced airway contraction to ∼70% of the original cross-sectional area within several seconds, and the contraction lasted for up to 40 s. The airway constriction could be mimicked by mechanical rupture of a single epithelial cell using a sharp glass micropipette but not with a blunt glass pipette. These results suggest that soluble mediators released from the wounded epithelial cell induce global airway contraction. To confirm this hypothesis, the lysate of primary human small airway epithelial cells stimulated a similar airway contraction. Laser ablation of single epithelial cells triggered a single instantaneous Ca(2+) wave in the epithelium, and multiple Ca(2+) waves in smooth muscle cells, which were delayed by several seconds. Removal of extracellular Ca(2+) or decreasing intracellular Ca(2+) both blocked laser-induced airway contraction. We conclude that local epithelial cell rupture induces rapid and global airway constriction through release of soluble mediators and subsequent Ca(2+)-dependent smooth muscle shortening.

Bud detachment in hydra requires activation of fibroblast growth factor receptor and a Rho–ROCK–myosin II signaling pathway to ensure formation of a basal constriction

PubMed Central

Holz, Oliver; Apel, David; Steinmetz, Patrick; Lange, Ellen; Hopfenmüller, Simon; Ohler, Kerstin; Sudhop, Stefanie

2017-01-01

Background: Hydra propagates asexually by exporting tissue into a bud, which detaches 4 days later as a fully differentiated young polyp. Prerequisite for detachment is activation of fibroblast growth factor receptor (FGFR) signaling. The mechanism which enables constriction and tissue separation within the monolayered ecto‐ and endodermal epithelia is unknown. Results: Histological sections and staining of F‐actin by phalloidin revealed conspicuous cell shape changes at the bud detachment site indicating a localized generation of mechanical forces and the potential enhancement of secretory functions in ectodermal cells. By gene expression analysis and pharmacological inhibition, we identified a candidate signaling pathway through Rho, ROCK, and myosin II, which controls bud base constriction and rearrangement of the actin cytoskeleton. Specific regional myosin phosphorylation suggests a crucial role of ectodermal cells at the detachment site. Inhibition of FGFR, Rho, ROCK, or myosin II kinase activity is permissive for budding, but represses myosin phosphorylation, rearrangement of F‐actin and constriction. The young polyp remains permanently connected to the parent by a broad tissue bridge. Conclusions: Our data suggest an essential role of FGFR and a Rho‐ROCK‐myosin II pathway in the control of cell shape changes required for bud detachment. Developmental Dynamics 246:502–516, 2017. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists PMID:28411398

Bud detachment in hydra requires activation of fibroblast growth factor receptor and a Rho-ROCK-myosin II signaling pathway to ensure formation of a basal constriction.

PubMed

Holz, Oliver; Apel, David; Steinmetz, Patrick; Lange, Ellen; Hopfenmüller, Simon; Ohler, Kerstin; Sudhop, Stefanie; Hassel, Monika

2017-07-01

Hydra propagates asexually by exporting tissue into a bud, which detaches 4 days later as a fully differentiated young polyp. Prerequisite for detachment is activation of fibroblast growth factor receptor (FGFR) signaling. The mechanism which enables constriction and tissue separation within the monolayered ecto- and endodermal epithelia is unknown. Histological sections and staining of F-actin by phalloidin revealed conspicuous cell shape changes at the bud detachment site indicating a localized generation of mechanical forces and the potential enhancement of secretory functions in ectodermal cells. By gene expression analysis and pharmacological inhibition, we identified a candidate signaling pathway through Rho, ROCK, and myosin II, which controls bud base constriction and rearrangement of the actin cytoskeleton. Specific regional myosin phosphorylation suggests a crucial role of ectodermal cells at the detachment site. Inhibition of FGFR, Rho, ROCK, or myosin II kinase activity is permissive for budding, but represses myosin phosphorylation, rearrangement of F-actin and constriction. The young polyp remains permanently connected to the parent by a broad tissue bridge. Our data suggest an essential role of FGFR and a Rho-ROCK-myosin II pathway in the control of cell shape changes required for bud detachment. Developmental Dynamics 246:502-516, 2017. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

Characterizing deformability and surface friction of cancer cells

PubMed Central

Byun, Sangwon; Son, Sungmin; Amodei, Dario; Cermak, Nathan; Shaw, Josephine; Kang, Joon Ho; Hecht, Vivian C.; Winslow, Monte M.; Jacks, Tyler; Mallick, Parag; Manalis, Scott R.

2013-01-01

Metastasis requires the penetration of cancer cells through tight spaces, which is mediated by the physical properties of the cells as well as their interactions with the confined environment. Various microfluidic approaches have been devised to mimic traversal in vitro by measuring the time required for cells to pass through a constriction. Although a cell’s passage time is expected to depend on its deformability, measurements from existing approaches are confounded by a cell's size and its frictional properties with the channel wall. Here, we introduce a device that enables the precise measurement of (i) the size of a single cell, given by its buoyant mass, (ii) the velocity of the cell entering a constricted microchannel (entry velocity), and (iii) the velocity of the cell as it transits through the constriction (transit velocity). Changing the deformability of the cell by perturbing its cytoskeleton primarily alters the entry velocity, whereas changing the surface friction by immobilizing positive charges on the constriction's walls primarily alters the transit velocity, indicating that these parameters can give insight into the factors affecting the passage of each cell. When accounting for cell buoyant mass, we find that cells possessing higher metastatic potential exhibit faster entry velocities than cells with lower metastatic potential. We additionally find that some cell types with higher metastatic potential exhibit greater than expected changes in transit velocities, suggesting that not only the increased deformability but reduced friction may be a factor in enabling invasive cancer cells to efficiently squeeze through tight spaces. PMID:23610435

Isobaric Tags for Relative and Absolute Quantitation-Based Proteomic Analysis of Patent and Constricted Ductus Arteriosus Tissues Confirms the Systemic Regulation of Ductus Arteriosus Closure.

PubMed

Hong, Haifa; Ye, Lincai; Chen, Huiwen; Xia, Yu; Liu, Yue; Liu, Jinfen; Lu, Yanan; Zhang, Haibo

2015-08-01

We aimed to evaluate global changes in protein expression associated with patency by undertaking proteomic analysis of human constricted and patent ductus arteriosus (DA). Ten constricted and 10 patent human DAs were excised from infants with ductal-dependent heart disease during surgery. Using isobaric tags for relative and absolute quantitation-based quantitative proteomics, 132 differentially expressed proteins were identified. Of 132 proteins, voltage-gated sodium channel 1.3 (SCN3A), myosin 1d (Myo1d), Rho GTPase activating protein 26 (ARHGAP26), and retinitis pigmentosa 1 (RP1) were selected for validation by Western blot and quantitative real-time polymerase chain reaction analyses. Significant upregulation of SCN3A, Myo1d, and RP1 messenger RNA, and protein levels was observed in the patent DA group (all P ≤ 0.048). ARHGAP26 messenger RNA and protein levels were decreased in patent DA tissue (both P ≤ 0.018). Immunohistochemistry analysis revealed that Myo1d, ARHGAP26, and RP1 were specifically expressed in the subendothelial region of constricted DAs; however, diffuse expression of these proteins was noted in the patent group. Proteomic analysis revealed global changes in the expression of proteins that regulate oxygen sensing, ion channels, smooth muscle cell migration, nervous system, immune system, and metabolism, suggesting a basis for the systemic regulation of DA patency by diverse signaling pathways, which will be confirmed in further studies.

Functional ET(A)-ET(B) Receptor Cross-talk in Basilar Artery In Situ From ET(B) Receptor Deficient Rats.

PubMed

Yoon, SeongHun; Gariepy, Cheryl E; Yanagisawa, Masashi; Zuccarello, Mario; Rapoport, Robert M

2016-03-01

The role of endothelin (ET)(A)-ET(B) receptor cross-talk in limiting the ET(A) receptor antagonist inhibition of ET-1 constriction is revealed by the partial or complete dependency of the ET(A) receptor antagonist inhibition on functional removal of the ET(B) receptor. Although functional removal of the ET(B) receptor is generally accomplished with ET(B) receptor antagonist, a novel approach using rats containing a naturally occurring deletion mutation in the ET(B) receptor [rescued "spotting lethal" (sl) rats; ET(B)(sl/sl)] demonstrated increased ET(A) receptor antagonist inhibition of ET-1 constriction in vena cava. We investigated whether this deletion mutation was also sufficient to remove the ET(B) receptor dependency of the ET(A) receptor antagonist inhibition of ET-1 constriction in the basilar artery. Consistent with previous reports, ET-1 plasma levels were elevated in ET(B)(sl/sl) as compared with ET(B)(+/+) rats. ET(B) receptor antagonist failed to relax the ET-1 constricted basilar artery from ET(B)(+/+) and ET(B)(sl/sl) rats. Relaxation to combined ET(A) and ET(B) receptor antagonist was greater than relaxation to ET(A) receptor antagonist in the basilar artery from ET(B)(+/+) and, unexpectedly, ET(B)(sl/sl) rats. These findings confirm the presence of ET(A)-ET(B) receptor cross-talk in the basilar artery. We speculate that mutant ET(B) receptor expression produced by alternative splicing may be sufficient to allow cross-talk.

Mechanical behavior of surgical meshes for abdominal wall repair: In vivo versus biaxial characterization.

PubMed

Simón-Allué, R; Ortillés, A; Calvo, B

2018-06-01

Despite the widespread use of synthetic meshes in the surgical treatment of the hernia pathology, the election criteria of a suitable mesh for specific patient continues to be uncertain. Thus, in this work, we propose a methodology to determine in advance potential disadvantages on the use of certain meshes based on the patient-specific abdominal geometry and the mechanical features of the certain meshes. To that purpose, we have first characterized the mechanical behavior of four synthetic meshes through biaxial tests. Secondly, two of these meshes were implanted in several New Zealand rabbits with a total defect previously created on the center of the abdominal wall. After the surgical procedure, specimen were subjected to in vivo pneumoperitoneum tests to determine the immediate post-surgical response of those meshes after implanted in a healthy specimen. Experimental performance was recorded by a stereo rig with the aim of obtaining quantitative information about the pressure-displacement relation of the abdominal wall. Finally, following the procedure presented in prior works (Simón-Allué et al., 2015, 2017), a finite element model was reconstructed from the experimental measurements and tests were computationally reproduced for the healthy and herniated cases. Simulations were compared and validated with the in vivo behavior and results were given along the abdominal wall in terms of displacements, stresses and strain. Mechanical characterization of the meshes revealed Surgipro TM as the most rigid implant and Neomesh SuperSoft® as the softer, while other two meshes (Neomesh Soft®, Neopore®) remained in between. These two meshes were employed in the experimental study and resulted in similar effect in the abdominal wall cavity and both were close to the healthy case. Simulations confirmed this result while showed potential objections in the case of the other two meshes, due to high values in stresses or elongation that may led to discomfort in real tissue. The use of this methodology on human surgery may provide the surgeons with reliable and useful information to avoid certain meshes on specific-patient treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Neural basis of singing in crickets: central pattern generation in abdominal ganglia

NASA Astrophysics Data System (ADS)

Schöneich, Stefan; Hedwig, Berthold

2011-12-01

The neural mechanisms underlying cricket singing behavior have been the focus of several studies, but the central pattern generator (CPG) for singing has not been localized conclusively. To test if the abdominal ganglia contribute to the singing motor pattern and to analyze if parts of the singing CPG are located in these ganglia, we systematically truncated the abdominal nerve cord of fictively singing crickets while recording the singing motor pattern from a front-wing nerve. Severing the connectives anywhere between terminal ganglion and abdominal ganglion A3 did not preclude singing, although the motor pattern became more variable and failure-prone as more ganglia were disconnected. Singing terminated immediately and permanently after transecting the connectives between the metathoracic ganglion complex and the first unfused abdominal ganglion A3. The contribution of abdominal ganglia for singing pattern generation was confirmed by intracellular interneuron recordings and current injections. During fictive singing, an ascending interneuron with its soma and dendrite in A3 depolarized rhythmically. It spiked 10 ms before the wing-opener activity and hyperpolarized in phase with the wing-closer activity. Depolarizing current injection elicited rhythmic membrane potential oscillations and spike bursts that elicited additional syllables and reliably reset the ongoing chirp rhythm. Our results disclose that the abdominal ganglion A3 is directly involved in generating the singing motor pattern, whereas the more posterior ganglia seem to provide only stabilizing feedback to the CPG circuit. Localizing the singing CPG in the anterior abdominal neuromeres now allows analyzing its circuitry at the level of identified interneurons in subsequent studies.

[Evaluation of anger expression, school functioning and a level of anxiety in children and adolescents with functional abdominal pain].

PubMed

Marczyńska, Paulina; Kowalkowska, Katarzyna; Kuczyńska, Renata; Czerwionka-Szaflarska, Mieczysława; Krogulska, Aneta

Psychosocial conditions may have influence on the occurrence of functional abdominal pain. Anxiety, school-related difficulties and suppression of emotions negatively impact on the psychosocial condition of a child and could impede its treatment. The analysis of the psychosocial determinants of functioning of children and adolescents with functional abdominal pain. Meterial and methods: The study group comprised 58 patients (12 boys and 46 girls) from 9 to 17 years of age (av. 13.34±2.14 years) with functional abdominal pain, diagnosed according to the III Roman Criteria, and the control group of 58 healthy children in adequate age, of Bydgoszcz primary and secondary schools. The test method utilised The Anger Regulation and Expression Scale (SEG), The State-Trait Anxiety Inventory for Children (STAIC) and Me and My School Questionnaire. Analysing the results of scale SEG between the group of children with functional abdominal pain and healthy children, significant differences were observed in the scale of external anger (p=0.045). There were no differences between the group of children with functional abdominal pain and the comparative one in terms of Me and My School Inventory scale (p> 0.05). In the group of healthy adolescents, the average of motivation differed significantly from the result of the adolescents with functional abdominal pain (p=0.031). There were no differences between the group of children and adolescents with abdominal pain and the healthy ones in terms of the performance in STAIC scales (p>0.05). 1. Healthy children compared to children with functional abdominal pain more openly express negative emotions, such as anger and irritation, which can cause reduced tendency to the somatization of symptoms. 2. Symptoms of young people with functional abdominal pain intensify reluctance to fulfill school duties and heighten fear of school, depending on the speed of activation of the autonomic nervous system.

Can We Perform CT of the Appendix with Less Than 1 mSv? A De-escalating Dose-simulation Study.

PubMed

Park, Ji Hoon; Jeon, Jong-June; Lee, Sung Soo; Dhanantwari, Amar C; Sim, Ji Ye; Kim, Hae Young; Lee, Kyoung Ho

2018-05-01

To systematically explore the lowest reasonably achievable radiation dose for appendiceal CT using an iterative reconstruction (IR) in young adults. We prospectively included 30 patients who underwent 2.0-mSv CT for suspected appendicitis. From the helical projection data, 1.5-, 1.0- and 0.5-mSv CTs were generated using a low-dose simulation tool and the knowledge-based IR. We performed step-wise non-inferiority tests sequentially comparing 2.0-mSv CT with each of 1.5-, 1.0- and 0.5-mSv CT, with a predetermined non-inferiority margin of 0.06. The primary end point was the pooled area under the receiver-operating-characteristic curve (AUC) for three abdominal and three non-abdominal radiologists. For the abdominal radiologists, the non-inferiorities of 1.5-, 1.0- and 0.5-mSv CT to 2.0-mSv CT were sequentially accepted [pooled AUC difference: 2.0 vs. 0.5 mSv, 0.017 (95% CI: -0.016, 0.050)]. For the non-abdominal radiologists, the non-inferiorities of 1.5- and 1.0-mSv CT were accepted; however, the non-inferiority of 0.5-mSv CT could not be proved [pooled AUC difference: 2.0 vs. 1.0 mSv, -0.017 (-0.070, 0.035) and 2.0 vs. 0.5 mSv, 0.045 (-0.071, 0.161)]. The 1.0-mSv appendiceal CT was non-inferior to 2.0-mSv CT in terms of diagnostic performance for both abdominal and non-abdominal radiologists; 0.5-mSv appendiceal CT was non-inferior only for abdominal radiologists. • For both abdominal and non-abdominal radiologists, 1.0-mSv appendiceal CT could be feasible. • The 0.5-mSv CT was non-inferior to 2.0-mSv CT only for expert abdominal radiologists. • Reader experience is an important factor affecting diagnostic impairment by low-dose CT.

Left hepatic lobe herniation through an incisional anterior abdominal wall hernia and right adrenal myelolipoma: a case report and review of the literature.

PubMed

Nuño-Guzmán, Carlos M; Arróniz-Jáuregui, José; Espejo, Ismael; Valle-González, Jesús; Butus, Hernán; Molina-Romo, Alejandro; Orranti-Ortega, Rodrigo I

2012-01-10

Herniation of the liver through an anterior abdominal wall hernia defect is rare. To the best of our knowledge, only three cases have been described in the literature. A 70-year-old Mexican woman presented with a one-week history of right upper quadrant abdominal pain, nausea, vomiting, and jaundice to our Department of General Surgery. Her medical history included an open cholecystectomy from 20 years earlier and excessive weight. She presented with jaundice, abdominal distension with a midline surgical scar, right upper quadrant tenderness, and a large midline abdominal wall defect with dullness upon percussion and protrusion of a large, tender, and firm mass. The results of laboratory tests were suggestive of cholestasis. Ultrasound revealed choledocholithiasis. A computed tomography scan showed a protrusion of the left hepatic lobe through the anterior abdominal wall defect and a well-defined, soft tissue density lesion in the right adrenal topography. An endoscopic common bile duct stone extraction was unsuccessful. During surgery, the right adrenal tumor was resected first. The hernia was approached through a median supraumbilical incision; the totality of the left lobe was protruding through the abdominal wall defect, and once the lobe was reduced to its normal position, a common bile duct surgical exploration with multiple stone extraction was performed. Finally, the abdominal wall was reconstructed. Histopathology revealed an adrenal myelolipoma. Six months after the operation, our patient remains in good health. The case of liver herniation through an incisional anterior abdominal wall hernia in this report represents, to the best of our knowledge, the fourth such case reported in the literature. The rarity of this medical entity makes it almost impossible to specifically describe predisposing risk factors for liver herniation. Obesity, the right adrenal myelolipoma mass effect, and the previous abdominal surgery are likely to have contributed to incisional hernia formation.

Infrared Video Pupillography Coupled with Smart Phone LED for Measurement of Pupillary Light Reflex.

PubMed

Chang, Lily Yu-Li; Turuwhenua, Jason; Qu, Tian Yuan; Black, Joanna M; Acosta, Monica L

2017-01-01

Clinical assessment of pupil appearance and pupillary light reflex (PLR) may inform us the integrity of the autonomic nervous system (ANS). Current clinical pupil assessment is limited to qualitative examination, and relies on clinical judgment. Infrared (IR) video pupillography combined with image processing software offer the possibility of recording quantitative parameters. In this study we describe an IR video pupillography set-up intended for human and animal testing. As part of the validation, resting pupil diameter was measured in human subjects using the NeurOptics ™ (Irvine, CA, USA) pupillometer, to compare against that measured by our IR video pupillography set-up, and PLR was assessed in guinea pigs. The set-up consisted of a smart phone with a light emitting diode (LED) strobe light (0.2 s light ON, 5 s light OFF cycles) as the stimulus and an IR camera to record pupil kinetics. The consensual response was recorded, and the video recording was processed using a custom MATLAB program. The parameters assessed were resting pupil diameter (D1), constriction velocity (CV), percentage constriction ratio, re-dilation velocity (DV) and percentage re-dilation ratio. We report that the IR video pupillography set-up provided comparable results as the NeurOptics ™ pupillometer in human subjects, and was able to detect larger resting pupil size in juvenile male guinea pigs compared to juvenile female guinea pigs. At juvenile age, male guinea pigs also had stronger pupil kinetics for both pupil constriction and dilation. Furthermore, our IR video pupillography set-up was able to detect an age-specific increase in pupil diameter (female guinea pigs only) and reduction in CV (male and female guinea pigs) as animals developed from juvenile (3 months) to adult age (7 months). This technique demonstrated accurate and quantitative assessment of pupil parameters, and may provide the foundation for further development of an integrated system useful for clinical applications.

Platelet-activating factor dilates efferent arterioles through glomerulus-derived nitric oxide.

PubMed

Arima, S; Ren, Y; Juncos, L A; Ito, S

1996-01-01

Despite evidence that platelet-activating factor (PAF) is produced by the glomerulus, its direct action on the glomerular microcirculation is poorly understood. It was recently reported that at picomolar concentrations, PAF dilates isolated microperfused afferent arterioles (Af-Art) via nitric oxide (NO). The present study tested the hypothesis that PAF acts on the glomerulus to release NO, which in turn controls the resistance of the efferent arteriole (Ef-Art). Rabbit Ef-Art were perfused from the distal end (retrograde perfusion [RP]) to eliminate the influence of the glomerulus, or through the glomerulus from the end of the Af-Art (orthograde perfusion [OP]) to maintain the influence of the glomerulus. Ef-Art were preconstricted by approximately 40% with norepinephrine and increasing doses of PAF were added to both the arteriolar perfusate and bath. Only with OP did PAF at picomolar concentrations cause significant dilation: at 400 pmol, the diameter increased by 64 +/- 11% from the preconstricted level (N = 6, P < 0.01). This dilation was completely abolished by pretreatment with an NO-synthesis inhibitor. To study its possible constrictor action, PAF was added to nonpreconstricted Ef-Art. At nanomolar concentrations, PAF constricted Ef-Art similarly in both RP and OP: at 40 nM, the diameter decreased by 24 +/- 4% (N = 6, P < 0.01) and 20 +/- 2% (N = 6, P < 0.01), respectively. This constriction was attenuated by pretreatment with indomethacin (Indo) in both RP (14 +/- 2%, N = 7; P < 0.02 versus without Indo) and OP (10 +/- 2%, N = 6; P < 0.02 versus without Indo). (1) at picomolar concentrations, PAF stimulates the glomerulus to release NO, which in turn dilates the Ef-Art; and (2) at nanomolar concentrations, PAF constricts the Ef-Art partly through release of cyclooxygenase metabolites. Thus, PAF may play a role in glomerular hemodynamics under various physiological and pathological conditions.

Tunable strength saddle-point contacts impact on quantum rings transmission

NASA Astrophysics Data System (ADS)

González, J. J.; Diago-Cisneros, L.

2016-09-01

A particular subject of investigation is the role of several sadle-point contact (QPC) parameters on the scattering properties of an Aharonov-Bohm-Aharonov-Casher quantum ring (QR) under Rashba-type spin orbit interaction. We discuss the interplay of the conductance with the confinement strengths and height of the QPC, which yields new and tunable harmonic and non-harmonics patterns, while one manipulates these constriction parameters. This phenomenology may be of utility to implement a novel way to modulate spin interference effects in semiconducting QRs, providing an appealing test-platform for spintronics applications.

Quantitative and qualitative testing of DARWeb: An online self-guided intervention for children with functional abdominal pain and their parents.

PubMed

Nieto, Rubén; Boixadós, Mercè; Hernández, Eulàlia; Beneitez, Imma; Huguet, Anna; McGrath, Patrick

2018-06-01

The main objective of this study was to preliminary explore the effects of DARWeb on different outcomes. A Quasi-experimental, one-group, pretest-posttest design was used. Parents and children were asked to complete questionnaires and questions (separately) about quality of life, abdominal pain severity, and satisfaction. Semi-structured interviews with families were also performed. This study focuses on 17 families. Results showed that parent's ratings of children's abdominal pain severity were significantly lower after finishing the intervention and at the 3-month follow-up, and quality of life scores had increased significantly after 3 months. From children's ratings, mean abdominal pain severity scores were significantly lower after the intervention compared to the preintervention assessment. Both parents and children were quite satisfied with the intervention. In qualitative interviews, families suggested that DARWeb helped them to give less importance to pain and to learn coping strategies. In conclusion, this study showed the potential usefulness of DARWeb for children with functional abdominal pain and for their parents.

Chronic ETA antagonist reverses hypertension and impairment of structure and function of peripheral small arteries in aortic stiffening.

PubMed

Guo, Xiaomei; Chen, Huan; Han, Ling; Haulon, Stephan; Kassab, Ghassan S

2018-02-15

Arterial stiffness may contribute to the pathogenesis of hypertension. The goal of this study is to elucidate the role of Endothelin-1 (ET-1) in aortic stiffening-induced hypertension through ET A receptor activation. An increase in aortic stiffness was created by use of a non-constrictive restraint, NCR on the abdominal aortic surface. A group of rats underwent aortic NCR or sham operation for 12 weeks and were then treated with ET A receptor antagonist BQ-123 for 3 weeks. We found that 12 weeks of aortic NCR significantly increased pulse and mean pressure and altered peripheral flow pattern, accompanied by an increased serum ET-1 level (p < 0.05). The increase in aortic stiffness (evidenced by an elevated pulse wave velocity) caused hypertrophic structural remodeling and decreased arterial compliance, along with an impaired endothelial function in peripheral small arteries. BQ-123 treatment only partially attenuated peripheral arterial hypertrophy and restored arterial compliance, but completely recovered endothelium function, and consequently restored local flow and lowered blood pressure. Our findings underscore the hemodynamic coupling between aortic stiffening and peripheral arterial vessels and flow dynamics through an ET A -dependent mechanism. ET A receptor blockade may have therapeutic potential for improving peripheral vessel structure and function in the treatment of aortic stiffness-induced hypertension.

Dilator and constrictor response of renal vasculature during acute renal hypotension in anesthetized goats. Role of nitric oxide.

PubMed

Diéguez, Godofredo; García-Villalón, Angel Luis

2011-01-01

The relative role of NO derived from endothelium NO synthase (eNOS) and neuronal NO synthase (nNOS) in renovascular reactivity during renal hypotension is unknown. To examine this issue, we recorded the effects of unspecific inhibitor of NO synthase N(w)-nitro-L-arginine methyl esther (L-NAME) and inhibitor of nNOS 7-nitroindazole monosodium salt (7-NINA) on renal vasodilator and vasoconstrictor responses in anesthetized goats during renal hypotension by constricting the abdominal aorta. Intrarenal administration of L-NAME and hypotension, either untreated or treated with L-NAME, decreased resting renal blood flow, and the increases in renal blood flow by acetylcholine but not those by sodium nitroprusside were tempered, and the decreases by norepinephrine and angiotensin II were augmented. Intraperitoneal administration of 7-NINA did not affect, and 7-NINA+hypotension decreased renal blood flow, and under these conditions the increases in renal blood flow by acetylcholine and sodium nitroprusside were not modified, and the decreases by norepinephrine and angiotensin II were slightly (during 7-NINA) or consistently augmented (7-NINA+hypotension). Therefore, NO derived from eNOS plays a significant role, while that derived from nNOS plays a little role, if any, to regulate renal blood flow and to mediate acetylcholine-induced vasodilation, as well to modulate renal vasoconstriction by norepinephrine and angiotensin II. Copyright © 2011 Elsevier Inc. All rights reserved.

Cardiac Protection of Valsartan on Juvenile Rats with Heart Failure by Inhibiting Activity of CaMKII via Attenuating Phosphorylation

PubMed Central

Wu, Yao; Si, Feifei; Ji, Xiaojuan; Jiang, Kunfeng; Song, Sijie

2017-01-01

Background. This study was undertaken to determine relative contributions of phosphorylation and oxidation to the increased activity of calcium/calmodulin-stimulated protein kinase II (CaMKII) in juveniles with cardiac myocyte dysfunction due to increased pressure overload. Methods. Juvenile rats underwent abdominal aortic constriction to induce heart failure. Four weeks after surgery, rats were then randomly divided into two groups: one group given valsartan (HF + Val) and the other group given placebo (HF + PBO). Simultaneously, the sham-operated rats were randomly given valsartan (Sham + Val) or placebo (Sham + PBO). After 4 weeks of treatment, Western blot analysis was employed to quantify CaMKII and relative calcium handling proteins (RyR2 and PLN) in all groups. Results. The deteriorated cardiac function was reversed by valsartan treatment. In ventricular muscle cells of group HF + PBO, Thr287 phosphorylation of CaMKII and S2808 phosphorylation of RyR2 and PLN were increased and S16 phosphorylation of PLN was decreased compared to the other groups, while Met281 oxidation was not significantly elevated. In addition, these changes in the expression of calcium handling proteins were ameliorated by valsartan administration. Conclusions. The phosphorylation of Thr286 is associated with the early activation of CaMKII rather than the oxidation of Met281. PMID:28536695

Fatal Clostridium perfringens sepsis due to emphysematous gastritis and literature review.

PubMed

Sarvari, Karoly Peter; Vasas, Bela; Kiss, Ildiko; Lazar, Andrea; Horvath, Istvan; Simon, Marianna; Peto, Zoltan; Urban, Edit

2016-08-01

A 76-year-old female patient was admitted to the Level I Emergency Department of University of Szeged with severe abdominal pain and vomiting. The clinical assessment with laboratory tests and radiological investigations confirmed severe sepsis associated with intravascular hemolysis and multiorgan failure and acute pancreatitis. On the abdominal CT, besides of other abnormalities, the presence of gas bubbles in the stomach, small intestines and liver were seen. The gastric alterations pointed to emphysematous gastritis. Despite of the medical treatment, the patient's condition quickly deteriorated and eight hours after admission the patient died. The autopsy evaluation revealed systemic infection of abdominal origin caused by gas-producing Gram-positive bacteria, and the post-mortem microbiological cultures confirmed the presence of Cloctridium perfringens in many abdominal organs. Emphysematous gastritis seemed to be the primary infectious focus. Copyright © 2016 Elsevier Ltd. All rights reserved.

Functional disability in paediatric patients with recurrent abdominal pain.

PubMed

Wendland, M; Jackson, Y; Stokes, L D

2010-07-01

Recurrent abdominal pain (RAP) is common in childhood, affecting approximately 12% of children and adolescents. Children with RAP tend to experience impairments in functioning, such as increased school absences, anxiety and depression. The current study investigated the potential influences on the relation between functional disability and RAP in 100 school-aged children. A series of hierarchical regression analyses were conducted to test two models: main effects and moderation of the relation between abdominal pain symptoms, child anxiety, child depression, maternal emotional distress, maternal encouragement of child illness behaviour and functional disability. The results indicated support for abdominal pain symptoms and child depression in predicting functional disability. The results also indicated that child anxiety and child depression each moderated the relation between pain symptoms and functional disability. Implications of the findings are discussed in terms of potential influences on the development of functional disability in youth.

Autocalibrating motion-corrected wave-encoding for highly accelerated free-breathing abdominal MRI.

PubMed

Chen, Feiyu; Zhang, Tao; Cheng, Joseph Y; Shi, Xinwei; Pauly, John M; Vasanawala, Shreyas S

2017-11-01

To develop a motion-robust wave-encoding technique for highly accelerated free-breathing abdominal MRI. A comprehensive 3D wave-encoding-based method was developed to enable fast free-breathing abdominal imaging: (a) auto-calibration for wave-encoding was designed to avoid extra scan for coil sensitivity measurement; (b) intrinsic butterfly navigators were used to track respiratory motion; (c) variable-density sampling was included to enable compressed sensing; (d) golden-angle radial-Cartesian hybrid view-ordering was incorporated to improve motion robustness; and (e) localized rigid motion correction was combined with parallel imaging compressed sensing reconstruction to reconstruct the highly accelerated wave-encoded datasets. The proposed method was tested on six subjects and image quality was compared with standard accelerated Cartesian acquisition both with and without respiratory triggering. Inverse gradient entropy and normalized gradient squared metrics were calculated, testing whether image quality was improved using paired t-tests. For respiratory-triggered scans, wave-encoding significantly reduced residual aliasing and blurring compared with standard Cartesian acquisition (metrics suggesting P < 0.05). For non-respiratory-triggered scans, the proposed method yielded significantly better motion correction compared with standard motion-corrected Cartesian acquisition (metrics suggesting P < 0.01). The proposed methods can reduce motion artifacts and improve overall image quality of highly accelerated free-breathing abdominal MRI. Magn Reson Med 78:1757-1766, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Student tutors are able to teach basic sonographic anatomy effectively - a prospective randomized controlled trial.

PubMed

Celebi, N; Zwirner, K; Lischner, U; Bauder, M; Ditthard, K; Schürger, S; Riessen, R; Engel, C; Balletshofer, B; Weyrich, P

2012-04-01

Ultrasound is a widely used diagnostic tool. In medical education, it can be used to teach sonographic anatomy as well as the basics of ultrasound diagnostics. Some medical schools have begun implementing student tutor-led teaching sessions in sonographic abdominal anatomy in order to meet the growing demand in ultrasound teaching. However, while this teaching concept has proven to be feasible and well accepted, there is limited data regarding its effectiveness. We investigated whether student tutors teach sonographic anatomy as effectively as faculty staff sonographers. 50 medical students were randomly assigned to one of two groups. 46 of these could be included in the analysis. One group was taught by student tutors (ST) and the other by a faculty staff sonographer (FS). Using a pre/post-test design, students were required to locate and label 15 different abdominal structures. They printed out three pictures in three minutes and subsequently labeled the structures they were able to identify. The pictures were then rated by two blinded faculty staff sonographers. A mean difference of one point in the improvement of correctly identified abdominal structures between the pre-test and post-test among the two groups was regarded as equivalent. In the pre-test, the ST (FS) correctly identified 1.6 ± 1.0 (2.0 ± 1.1) structures. Both the ST and FS group showed improvement in the post-test, correctly identifying 7.8 ± 2.8 vs. 8.9 ± 2.9 structures, respectively (p < .0001 each). Comparing the improvement of the ST (6.2 ± 2.8 structures) versus the FS (6.9 ± 3.2) showed equivalent results between the two groups (p < .05 testing for equivalence). Basic abdominal sonographic anatomy can be taught effectively by student tutors. © Georg Thieme Verlag KG Stuttgart · New York.

Ultrasound Assessment of Abdominal Muscle Thickness in Women With and Without Low Back Pain During Pregnancy.

PubMed

Weis, Carol Ann; Nash, Jennifer; Triano, John J; Barrett, Jon

2017-05-01

The aim of this preliminary study was to determine the differences in abdominal musculature thickness, within 1 month of delivery, in women who experienced back pain during pregnancy compared with those who did not. B-mode ultrasound imaging was used to measure abdominal muscle thickness on 76 postpartum participants who participated in a larger study; 47 women experienced back pain during pregnancy, and 29 did not. Participant data were stratified by group, and primary comparisons were based on these grouping across the abdominal muscles, including rectus abdominis (upper and lower fibers), external oblique, internal oblique, and transversus abdominis. Means and standard deviations were also used to set parameters for future studies. In the present study, there was no difference in any abdominal muscle thickness between groups. Women with low back pain were significantly shorter (165.19 ± 6.64 cm) than women who did not have from back pain during pregnancy (169.38 ± 7.58 cm). All other demographics, such as age, weight, and date tested postpartum, were not significantly different between groups. The results of this study showed no variation in abdominal muscle thickness in women who had back pain during pregnancy and those who did not. Copyright © 2017. Published by Elsevier Inc.

Invasive Candidiasis in Various Patient Populations: Incorporating Non-Culture Diagnostic Tests into Rational Management Strategies

PubMed Central

Clancy, Cornelius J.; Shields, Ryan K.; Nguyen, M. Hong

2016-01-01

Mortality rates due to invasive candidiasis remain unacceptably high, in part because the poor sensitivity and slow turn-around time of cultures delay the initiation of antifungal treatment. β-d-glucan (Fungitell) and polymerase chain reaction (PCR)-based (T2Candida) assays are FDA-approved adjuncts to cultures for diagnosing invasive candidiasis, but their clinical roles are unclear. We propose a Bayesian framework for interpreting non-culture test results and developing rational patient management strategies, which considers test performance and types of invasive candidiasis that are most common in various patient populations. β-d-glucan sensitivity/specificity for candidemia and intra-abdominal candidiasis is ~80%/80% and ~60%/75%, respectively. In settings with 1%–10% likelihood of candidemia, anticipated β-d-glucan positive and negative predictive values are ~4%–31% and ≥97%, respectively. Corresponding values in settings with 3%–30% likelihood of intra-abdominal candidiasis are ~7%–51% and ~78%–98%. β-d-glucan is predicted to be useful in guiding antifungal treatment for wide ranges of populations at-risk for candidemia (incidence ~5%–40%) or intra-abdominal candidiasis (~7%–20%). Validated PCR-based assays should broaden windows to include populations at lower-risk for candidemia (incidence ≥~2%) and higher-risk for intra-abdominal candidiasis (up to ~40%). In the management of individual patients, non-culture tests may also have value outside of these windows. The proposals we put forth are not definitive treatment guidelines, but rather represent starting points for clinical trial design and debate by the infectious diseases community. The principles presented here will be applicable to other assays as they enter the clinic, and to existing assays as more data become available from different populations. PMID:29376927

The effectiveness of empirical anti-parasitic treatment in returning travellers with persistent abdominal symptoms.

PubMed

Nissan, Batel; Lachish, Tamar; Schwartz, Eli

2018-01-01

Persistent abdominal symptoms (PAS) are common among returning-travellers. In the absence of sensitive tests to identify intestinal parasites, gastrointestinal (GI) symptoms often remain a diagnostic challenge. In this study we examined the effectiveness of empirical anti-parasitic treatment in returning-travellers with PAS despite no positive stool-test. A retrospective study among returning travellers who approached the clinic between the years 2014 and 2016 with GI complaints without a positive stool-test. The empirical treatment included broad-spectrum anti-parasitic agents-oral Tinidazole and Albendazole. A follow-up questionnaire was performed at least 6 months post-treatment. A total of 102 patients responded the questionnaire-50% women; average age 31.14 (±12.20) years. The average duration of complaints before treatment was 16.52 (±30.06) months. Common GI symptoms included abdominal pain (83.3%) and diarrhoea (78.4%); 67.6% of the patients complained of extreme fatigue. Overall, 69% of the patients reported an improvement in GI symptoms, 37% of them reported full recovery within a few weeks post-treatment. Furthermore, there was an improvement in the energy level and general well-being in 68% and 70% of the patients, respectively. Only 33% of the patients reported minor side effects related to the treatment. The improvement in GI symptoms, energy level and general well-being shortly after anti-parasitic treatment justifies this empirical approach in returning-travellers with PAS despite negative stool-tests. The association between fatigue and PAS post-travel and the improvement in both as a response to treatment defines fatigue as part of a new syndrome-'Post-travel fatigue and abdominal symptoms'. © International Society of Travel Medicine, 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Postoperative intra-abdominal collections using a sodium hyaluronate-carboxymethylcellulose (HA-CMC) barrier at the time of laparotomy for ovarian, fallopian tube, or primary peritoneal cancers.

PubMed

Leitao, Mario M; Natenzon, Anna; Abu-Rustum, Nadeem R; Chi, Dennis S; Sonoda, Yukio; Levine, Douglas A; Gardner, Ginger J; Barakat, Richard R

2009-11-01

To determine whether HA-CMC was associated with the development of postoperative intra-abdominal collections in patients undergoing laparotomy for ovarian, fallopian tube, or primary peritoneal malignancies. We retrospectively identified all laparotomies performed for these malignancies from March 1, 2005 to December 31, 2007. The use of HA-CMC was identified. Laparotomies for malignant bowel obstruction or repair of fistulae were excluded. Intra-abdominal collections, non-infected and infected, were defined as localized intraperitoneal fluid accumulations in the absence of re-accumulating ascites. All other complications were also captured. Appropriate statistical tests were applied using SPSS 15.0. We identified 219 laparotomies with HA-CMC and 204 without HA-CMC. Upper abdominal resections were performed in 65/219 (30%) HA-CMC cases compared to 39/204 (19%) cases without HA-CMC (P=0.01). The rates of large bowel and/or rectal resections were similar in both cohorts. Intra-abdominal collections were seen in 18/219 (8.2%) HA-CMC cases compared to 5/204 (2.5%) cases without HA-CMC (P=0.009). HA-CMC was independently associated with the diagnosis of a postoperative intra-abdominal collection (P=0.01). All but 2 collections developed in patients undergoing debulking procedures. HA-CMC appears to be associated with a higher rate of postoperative intra-abdominal collections. This seems to be greatest in patients who are undergoing a debulking procedure.

The Effects of Combined Exercise on Health-Related Fitness, Endotoxin, and Immune Function of Postmenopausal Women with Abdominal Obesity.

PubMed

Park, Sung-Mo; Kwak, Yi-Sub; Ji, Jin-Goo

2015-01-01

This study was conducted to examine the effects of combined exercise on health-related fitness, endotoxin concentrations, and immune functions of postmenopausal women with abdominal obesity. 20 voluntary participants were recruited and they were randomly allocated to the combined exercise group (n = 10) or the control group (n = 10). Visceral obesity was defined as a visceral-to-subcutaneous fat ratio ≥ 0.4 based on computed tomography (CT) results. Body composition, exercise stress testing, fitness measurement, CT scan, and blood variables were analyzed to elucidate the effects of combined exercise. The SPSS Statistics 18.0 program was used to calculate means and standard deviations for all variables. Significant differences between the exercise group and control group were determined with 2-way ANOVA and paired t-tests. The exercise group's abdominal obesity was mitigated due to visceral fat reduction; grip strength, push-ups, and oxygen uptake per weight improved; and HDL-C and IgA level also increased, while TNF-α, CD14, and endotoxin levels decreased. Lowered TNF-α after exercise might have an important role in the obesity reduction. Therefore, we can conclude that combined exercise is effective in mitigating abdominal obesity, preventing metabolic diseases, and enhancing immune function.

Mycobacteriosis in a Domestic Ferret (Mustela putorius furo)

PubMed Central

NAKATA, Makoto; MIWA, Yasutsugu; TSUBOI, Masaya; UCHIDA, Kazuyuki

2014-01-01

ABSTRACT A 4-year-old spayed female ferret presented with a 2-month history of anorexia, vomiting and occasional diarrhea. Abdominal ultrasonography revealed thickening of the gastric wall and enlarged abdominal lymph nodes. Biopsy samples from the thickened gastric wall, enlarged abdominal lymph nodes and liver were taken during an exploratory laparotomy. Based on the histopathological examination, mycobacterium infection was diagnosed. The bacterial species could not be identified by additional diagnostic tests of feces, including fecal smear, culture and polymerase chain reaction (PCR). The ferret was treated with prednisolone and multiple antimicrobials, including rifampicin, azithromycin and enrofloxacin, but did not improve with treatment and died 220 days after the first presentation. PMID:24419874

Ameliorative potential of Vernonia cinerea on chronic constriction injury of sciatic nerve induced neuropathic pain in rats.

PubMed

Thiagarajan, Venkata R K; Shanmugam, Palanichamy; Krishnan, Uma M; Muthuraman, Arunachalam

2014-08-29

The aim of the present study is to investigate the ameliorative potential of ethanolic extract of whole plant of Vernonia cinerea in the chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rats. Behavioral parameters such as a hot plate, acetone drop, paw pressure, Von Frey hair and tail immersion tests were performed to assess the degree of thermal, chemical and mechanical hyperalgesia and allodynia. Biochemical changes in sciatic nerve tissue were ruled out by estimating thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and total calcium levels. Ethanolic extract of Vernonia cinerea and pregabalin were administered for 14 consecutive days starting from the day of surgery. CCI of sciatic nerve has been shown to induce significant changes in behavioral, biochemical and histopathological assessments when compared to the sham control group. Vernonia cinerea attenuated in a dose dependent manner the above pathological changes induced by CCI of the sciatic nerve, which is similar to attenuation of the pregabalin pretreated group. The ameliorating effect of ethanolic extract of Vernonia cinerea against CCI of sciatic nerve induced neuropathic pain may be due to the presence of flavonoids and this effect is attributed to anti-oxidative, neuroprotective and calcium channel modulator actions of these compounds.

Ameliorative potential of Vernonia cinerea on chronic constriction injury of sciatic nerve induced neuropathic pain in rats.

PubMed

Thiagarajan, Venkata R K; Shanmugam, Palanichamy; Krishnan, Uma M; Muthuraman, Arunachalam

2014-09-01

The aim of the present study is to investigate the ameliorative potential of ethanolic extract of whole plant of Vernonia cinerea in the chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rats. Behavioral parameters such as a hot plate, acetone drop, paw pressure, Von Frey hair and tail immersion tests were performed to assess the degree of thermal, chemical and mechanical hyperalgesia and allodynia. Biochemical changes in sciatic nerve tissue were ruled out by estimating thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and total calcium levels. Ethanolic extract of Vernonia cinerea and pregabalin were administered for 14 consecutive days starting from the day of surgery. CCI of sciatic nerve has been shown to induce significant changes in behavioral, biochemical and histopathological assessments when compared to the sham control group. Vernonia cinerea attenuated in a dose dependent manner the above pathological changes induced by CCI of the sciatic nerve, which is similar to attenuation of the pregabalin pretreated group. The ameliorating effect of ethanolic extract of Vernonia cinerea against CCI of sciatic nerve induced neuropathic pain may be due to the presence of flavonoids and this effect is attributed to anti-oxidative, neuroprotective and calcium channel modulator actions of these compounds.

Role of splanchnic constriction in governing the hemodynamic responses to gravitational stress in conscious dogs

PubMed Central

Wong, Brett J.

2011-01-01

Octreotide is a somatostatin analog that constricts the splanchnic circulation, thereby improving orthostatic tolerance. We tested the hypotheses that octreotide improves orthostatic tolerance by 1)increasing cardiac filling (right atrial) pressure via reductions in vascular capacity; 2) by causing an upward (i.e., cranial) shift of the hydrostatic indifferent point; and 3) by increasing arterial pressure via a reduction in total vascular conductance. Studies were carried out in acepromazine-sedated, hexamethonium-treated atrioventricular-blocked conscious dogs lightly restrained in lateral recumbency. Beat-by-beat cardiac output was held constant via computer-controlled ventricular pacing at rest and during 30 s of 30° head-up tilt. Octreotide (1.5 μg/kg iv) raised right atrial pressure by 0.5 mmHg and raised mean arterial pressure by 11 mmHg by reducing total vascular conductance (all P < 0.05). Right atrial pressure fell by a similar amount in response to tilting before and after octreotide, thus there was no difference in location of the hydrostatic indifferent point. These data indicate that octreotide improves orthostatic tolerance by decreasing total vascular conductance and by increasing cardiac filling pressure via a reduction in unstressed vascular volume and not by eliciting a cranial shift of the location of the hydrostatic indifferent point. PMID:21512154

Grand rounds: asbestos-related pericarditis in a boiler operator.

PubMed

Abejie, Belayneh A; Chung, Eugene H; Nesto, Richard W; Kales, Stefanos N

2008-01-01

Occupational and environmental exposures to asbestos remain a public health problem even in developed countries. Because of the long latency in asbestos-related pathology, past asbestos exposure continues to contribute to incident disease. Asbestos most commonly produces pulmonary pathology, with asbestos-related pleural disease as the most common manifestation. Although the pleurae and pericardium share certain histologic characteristics, asbestos-related pericarditis is rarely reported. We present a 59-year-old man who worked around boilers for almost 30 years and was eventually determined to have calcific, constrictive pericarditis. He initially presented with an infectious exacerbation of chronic bronchitis. Chest radiographs demonstrated pleural and pericardial calcifications. Further evaluation with cardiac catheterization showed a hemodynamic picture consistent with constrictive pericarditis. A high-resolution computerized tomography scan of the chest demonstrated dense calcification in the pericardium, right pleural thickening and nodularity, right pleural plaque without calcification, and density in the right middle lobe. Pulmonary function testing showed mild obstruction and borderline low diffusing capacity. Based on the patient's occupational history, the presence of pleural pathology consistent with asbestos, previous evidence that asbestos can affect the pericardium, and absence of other likely explanations, we concluded that his pericarditis was asbestos-related. Similar to pleural thickening and plaque formation, asbestos may cause progressive fibrosis of the pericardium.

Differentiation of constrictive pericarditis from restrictive cardiomyopathy: the case for high-resolution dynamic tomographic imaging

NASA Astrophysics Data System (ADS)

Weiss, Robert M.; Otoadese, Eramosele A.; Oren, Ron M.

1995-05-01

The syndrome of constrictive pericarditis (CP) presents a diagnostic challenge to the clinician. This study was undertaken to determine whether cine computed tomography (CT), a cardiac imaging technique with excellent temporal and spatial resolution, can reliably demonstrate the unique abnormalities of pericardial anatomy and ventricular physiology present in patients with this condition. A second goal of this study was to determine whether the presence of diseased thickened pericardium, by itself, imparts cardiac impairment due to abnormalities of ventricular diastolic function. Methods: Twelve patients with CP suspected clinically, in whom invasive hemodynamic study was consistent with the diagnosis of CP, underwent cine CT. They were subdivided into Group 1 (CP, N equals 5) and Group 2 (No CP, N equals 7) based on histopathologic evaluation of tissue obtained at the time of surgery or autopsy. A third group consisted of asymptomatic patients with incidentally discovered thickened pericardium at the time of cine CT scanning: Group 3 (ThP, N equals 7). Group 4 (Nl, N equals 7) consisted of healthy volunteer subjects. Results: Pericardial thickness measurements with cine CT clearly distinguished Group 1 (mean equals 10 +/- 2 mm) from Group 2 (mean equals 2 +/- 1 mm), with diagnostic accuracy of 100% compared to histopathological findings. In addition, patients in Group 1 had significantly more brisk early diastolic filling of both left and right ventricles than those in Group 2, which clearly distinguished all patients with, from all patients without CP. Patients in Group 3 had pericardial thicknesses similar to those in Group 1 (mean equals 9 +/- 1 mm, p equals NS), but had patterns of diastolic ventricular filling that were nearly identical to Group 4 (Nl). Conclusions: The abnormalities of anatomy and ventricular function present in the syndrome of constrictive pericarditis are clearly and decisively identified by cine CT. This allows a reliable distinction between patients with constrictive pericarditis and those with cardiomyopathy. The presence of diseased thickened pericardium does not by itself impart impairment of ventricular diastolic function. Thus, definitive diagnosis of constrictive pericarditis requires demonstration of both abnormal anatomy and physiology.

Three new and a known species of the genus Proleptonchus Lordello, 1955 (Nematoda: Leptonchidae) with a diagnostic compendium of the genus.

PubMed

Ahad, Sumaya; Ahmad, Wasim

2016-11-09

This paper deals with the description of three new and one known species of the genus Proleptonchus Lordello, 1955. Proleptonchus kazirangus n. sp. from Kaziranga National Park, India is characterized by having 1.08-1.45 mm long body; cap-like, offset, lip region; 7-8 µm long odontostyle and 10-12 µm long odontophore; short, pear-shaped pharyngeal bulb offset by a constriction, occupying about 18-21% of total neck length; female genital system mono-prodelphic; pars dilatata uteri with distinctly sclerotized central lumen containing refringent apophyses; posterior uterine sac 78-112 µm long, with sac-like structure representing a rudimentary oviduct; transverse vulva, short, rounded-conoid tail and males with 31-33 µm long spicules, lateral guiding pieces and seven, regularly spaced ventromedian supplements. P. prerectus n. sp. from Japan is characterized by having 1.18-1.43 mm long body; lip region cap-like, offset by a slight constriction; odontostyle 8 µm, odontophore 9-10 µm; short cylindroid basal bulb offset by a constriction, occupying about 16-20% of total neck length; female genital system mono-prodelphic; pars dilatata uteri with sclerotized refringent apophyses; posterior uterine sac small, 27-36 µm; transverse vulva; a prerectal chamber and short, rounded-hemispheroid tail. P. japonicus n. sp. also from Japan is characterized by having 0.91-1.04 mm long body; lip region cap-like, set off by a slight constriction; odontostyle 5 µm and odontophore 10-11 µm long; pharynx consists of a very slender, non-muscular anterior part, separated from pyriform basal bulb by a constriction, with thickened lumen in posterior region, occupying about 18-20% of total neck length; female genital system mono-prodelphic; posterior uterine sac small, 20-24 µm long; transverse vulva and short, rounded-conoid tail. P. shamimi Bajaj & Bhatti, 1980 is redescribed and its relationship with closely related species is discussed. A diagnostic compendium of all the valid species of Proleptonchus is also provided.

Deflection measurement system for the hybrid iii six-year-old biofidelic abdomen.

PubMed

Gregory, T Stan; Howes, Meghan K; Rouhana, Stephen W; Hardy, Warren N

2012-01-01

Motor vehicle collisions are the leading cause of death for children ages 5 to 14. Enhancement of child occupant protection is partly dependent on the ability to accurately assess the interaction of child-size occupants with restraint systems. Booster seat design and belt fit are evaluated using child anthropomorphic test devices, such as the Hybrid III 6-year-old dummy., A biofidelic abdomen for the Hybrid III 6-year-old dummy is being developed by the Ford Motor Company to enhance the dummy’s ability to assess injury risk and further quantify submarining risk by measuring abdominal deflection. A practical measurement system for the biofidelic abdominal insert has been developed and demonstrated for three dimensional determination of abdominal deflection. Quantification of insert deflection is achieved via differential signal measurement using electrodes mounted within a conductive medium. Signal amplitude is proportional to the distance between the electrodes. A microcontroller is used to calculate distances between ventral electrodes and a dorsal electrode in three dimensions. This system has been calibrated statically, and its performance demonstrated in a series of sled tests. Deflection measurements from the instrumented abdominal insert indicate performance differences between two booster seat designs, yielding an average peak anterior to posterior displacement of the abdomen of 1.0 ± 3.4 mm and 31.2 ± 7.2 mm for the seats, respectively. Implementation of a 6-year-old abdominal insert with the ability to evaluate submarining potential will likely help safety researchers further enhance booster seat design and interaction with vehicle restraint systems , and help to further understand child occupant injury risk in automobile collisions.

Association of industry sponsorship and positive outcome in randomised controlled trials in general and abdominal surgery: protocol for a systematic review and empirical study.

PubMed

Probst, Pascal; Grummich, Kathrin; Ulrich, Alexis; Büchler, Markus W; Knebel, Phillip; Diener, Markus K

2014-11-27

Industry sponsorship has been identified as a factor correlating with positive research findings in several fields of medical science. To date, the influence of industry sponsorship in general and abdominal surgery has not been fully studied. This protocol describes the rationale and planned conduct of a systematic review to determine the association between industry sponsorship and positive outcome in randomised controlled trials in general and abdominal surgery. A literature search in the Cochrane Library, MEDLINE and EMBASE and additional hand searches in relevant citations will be conducted. In order to cover all relevant areas of general and abdominal surgery, a new literature search strategy called multi-PICO search strategy (MPSS) has been developed. No language restriction will be applied. The search will be limited to publications between January 1985 and July 2014. Information on funding source, outcome, study characteristics and methodological quality will be extracted.The association between industry sponsorship and positive outcome will be tested by a chi-squared test. A multivariate logistic regression analysis will be performed to control for possible confounders, such as number of study centres, multinational trials, methodological quality, journal impact factor and sample size. This study was designed to clarify whether industry-sponsored trials report more positive outcomes than non-industry trials. It will be the first study to evaluate this topic in general and abdominal surgery. The findings of this study will enable surgical societies, in particular, to give advice about cooperation with the industry and disclosure of funding source based on empirical evidence. PROSPERO CRD42014010802.

Case of emphysematous cholecystitis in a patient with type 2 diabetes mellitus associated with schizophrenia.

PubMed

Ogawa, Ayu; Shikata, Kenichi; Uchida, Haruhito Adam; Shinoura, Susumu; Yokomichi, Naosuke; Ogawa, Daisuke; Sato-Horiguchi, Chicage; Yagi, Takahito; Wada, Jun; Makino, Hirofumi

2012-12-20

Emphysematous cholecystitis is a rare, but life-threatening, form of acute cholecystitis caused by gas-forming organisms in the gallbladder. A 73-year-old male patient with type 2 diabetes mellitus complicated with neuropathy associated with schizophrenia was admitted to Okayama University Hospital, Okayama, Japan, because of a high fever and general malaise. On the fourth hospital day, despite normal liver function tests and little abdominal pain, his abdominal computed tomography showed huge gas formation in the gallbladder lumen along with a dilated gallbladder with a thickened wall, consistent with emphysematous cholecystitis. The patient underwent an emergency open cholecystectomy. Few abdominal symptoms appeared because of the hyposensitivity to pain caused by not only diabetic neuropathy, but also antipsychotic agents the patient was taking for schizophrenia. Emphysematous cholecystitis should be taken into consideration for the differential diagnosis of high fever in diabetic patients with schizophrenia, irrespective of the level of liver function tests and clinical symptoms.