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Sample records for salamander prevent morbidity

  1. Cutaneous Bacteria of the Redback Salamander Prevent Morbidity Associated with a Lethal Disease

    PubMed Central

    Becker, Matthew H.; Harris, Reid N.

    2010-01-01

    Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is an infectious disease that causes population declines of many amphibians. Cutaneous bacteria isolated from redback salamanders, Plethodon cinereus, and mountain yellow-legged frogs, Rana muscosa, inhibit the growth of Bd in vitro. In this study, the bacterial community present on the skin of P. cinereus individuals was investigated to determine if it provides protection to salamanders from the lethal and sub-lethal effects of chytridiomycosis. When the cutaneous bacterial community was reduced prior to Bd exposure, salamanders experienced a significantly greater decrease in body mass, which is a symptom of the disease, when compared to infected individuals with a normal bacterial community. In addition, a greater proportion of infected individuals with a reduced bacterial community experienced limb-lifting, a behavior seen only in infected individuals. Overall, these results demonstrate that the cutaneous bacterial community of P. cinereus provides protection to the salamander from Bd and that alteration of this community can change disease resistance. Therefore, symbiotic microbes associated with this species appear to be an important component of its innate skin defenses. PMID:20532032

  2. Cutaneous bacteria of the redback salamander prevent morbidity associated with a lethal disease.

    PubMed

    Becker, Matthew H; Harris, Reid N

    2010-01-01

    Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is an infectious disease that causes population declines of many amphibians. Cutaneous bacteria isolated from redback salamanders, Plethodon cinereus, and mountain yellow-legged frogs, Rana muscosa, inhibit the growth of Bd in vitro. In this study, the bacterial community present on the skin of P. cinereus individuals was investigated to determine if it provides protection to salamanders from the lethal and sub-lethal effects of chytridiomycosis. When the cutaneous bacterial community was reduced prior to Bd exposure, salamanders experienced a significantly greater decrease in body mass, which is a symptom of the disease, when compared to infected individuals with a normal bacterial community. In addition, a greater proportion of infected individuals with a reduced bacterial community experienced limb-lifting, a behavior seen only in infected individuals. Overall, these results demonstrate that the cutaneous bacterial community of P. cinereus provides protection to the salamander from Bd and that alteration of this community can change disease resistance. Therefore, symbiotic microbes associated with this species appear to be an important component of its innate skin defenses. PMID:20532032

  3. First report of a ranavirus associated with morbidity and mortality in farmed Chinese giant salamanders (Andrias davidianus).

    PubMed

    Geng, Y; Wang, K Y; Zhou, Z Y; Li, C W; Wang, J; He, M; Yin, Z Q; Lai, W M

    2011-07-01

    From February to May 2010, an outbreak of disease occurred amongst farmed Chinese giant salamanders (Andrias davidianus) in Hanzhong County, Shanxi Province, China. Clinical signs included anorexia, lethargy, ecchymoses and swollen areas on the head and limbs, and skin ulceration. The aim of this study was to determine the cause of this disease. Necropsy examination revealed subcutaneous and intramuscular oedema, swollen and pale livers with multifocal haemorrhage, swollen kidneys with multifocal haemorrhage and distended fluid-filled intestines with areas of haemorrhage. Light microscopy revealed intracytoplasmic inclusions suggestive of a viral infection in a variety of organs, as well as degeneration and necrosis of these organs. Electron microscopy of ultrathin sections of the same tissues revealed iridovirus-like particles within the inclusions. Of the six specimens tested, all were positive for ranavirus major capsid protein (MCP) gene. Sequence alignments of the ranavirus MCP gene from these specimens showed 95-98% similarity with published ranavirus data. The virus, provisionally designated as Chinese giant salamander virus (CGSV), was isolated from tissue homogenates of diseased salamanders following inoculation of epithelioma papilloma cyprini cells. Sequence analysis of the MCP genes showed that the isolated virus was a ranavirus with marked sequence identity to other members of the genus Ranavirus. Koch's postulates were fulfilled by infecting healthy Chinese giant salamanders with the CGSV. These salamanders all died within 6-8 days. This is the first report of ranavirus infection associated with mass mortality in Chinese giant salamanders. PMID:21256507

  4. Recording actions to prevent child morbidity in children's health cards.

    PubMed

    Vieira, Daniele de Souza; Santos, Nathanielly Cristina Carvalho de Brito; Costa, Dayse Kalyne Gomes da; Pereira, Mayara de Melo; Vaz, Elenice Maria Cecchetti; Reichert, Altamira Pereira da Silva

    2016-06-01

    The aim of this study was to analyze the registering of preventative actions in relation to child morbidity using information regarding vaccinations, as well as iron and vitamin A supplements, which are recorded in children's health cards. This transversal study used a quantitative approach and was performed in Family Health Units in the city of João Pessoa, Paraíba; the sampling was by convenience and totaled 116 children's health cards. The data was collected by observing the cards and the analysis was simple, statistical. The highest percentage of children had their vaccination cards up to date (92.2%) and those that did not were aged between 6 and 12 months: 78.9% of the cards did not have records relating to iron and vitamin A supplements and others only had records of one of the supplements being administered. The vaccination status of children in the first year of life was found to be satisfactory; however, discrepancies were observed in the recordings of the administration of iron and vitamin A supplements, which complicates monitoring performed by child health care professionals. It is hoped that this study will contribute to discussions and strategies aimed at improving the monitoring and recording of micronutrients in children's health cards. PMID:27383363

  5. The prevention of psychological morbidity following perinatal death.

    PubMed Central

    Hammersley, L; Drinkwater, C

    1997-01-01

    In recent years, a significant volume of hospital-based literature has been produced about the management of women and their families after a perinatal death. There has also been a considerable amount of work in the voluntary sector which has recognized this as an area of unmet need. The introduction of regional neonatal intensive care units and the shift from secondary to primary care make the development of a structured community-based approach for this group of vulnerable patients increasingly important. This article documents the evidence for high levels of psychological morbidity following perinatal death, reviews a variety of interventions designed to reduce morbidity, and makes some tentative proposals about the key elements of an effective community-based support programme. PMID:9406496

  6. The New Morbidity and the Prevention of Mental Retardation.

    ERIC Educational Resources Information Center

    Baumeister, Alfred A.

    1988-01-01

    Efforts to prevent mental retardation have been encumbered by lack of scientific and technical knowledge, vague understanding of incidence and prevalence, and scarcity of resources to implement effective public policies. Scientific and social progress toward prevention has pursued a wavelike, erratic course, driven primarily by prevailing social,…

  7. Preventing cold-related morbidity and mortality in a changing climate

    PubMed Central

    Conlon, Kathryn C; Rajkovich, Nicholas B; White-Newsome, Jalonne L; Larsen, Larissa; Neill, Marie S O

    2011-01-01

    Winter weather patterns are anticipated to become more variable with increasing average global temperatures. Research shows that excess morbidity and mortality occurs during cold weather periods. We critically reviewed evidence relating temperature variability, health outcomes, and adaptation strategies to cold weather. Health outcomes included cardiovascular-, respiratory-, cerebrovascular-, and all-cause morbidity and mortality. Individual and contextual risk factors were assessed to highlight associations between individual- and neighborhood- level characteristics that contribute to a person’s vulnerability to variability in cold weather events. Epidemiologic studies indicate that the populations most vulnerable to variations in cold winter weather are the elderly, rural and, generally, populations living in moderate winter climates. Fortunately, cold-related morbidity and mortality are preventable and strategies exist for protecting populations from these adverse health outcomes. We present a range of adaptation strategies that can be implemented at the individual, building, and neighborhood level to protect vulnerable populations from cold-related morbidity and mortality. The existing research justifies the need for increased outreach to individuals and communities for education on protective adaptations in cold weather. We propose that future climate change adaptation research couple building energy and thermal comfort models with epidemiological data to evaluate and quantify the impacts of adaptation strategies. PMID:21592693

  8. Patient and provider perspectives on the relationship between multiple morbidity management and disease prevention.

    PubMed

    Schoenberg, Nancy E; Tarasenko, Yelena N; Bardach, Shoshana H; Fleming, Steven T

    2015-04-01

    Despite competing demands of multiple morbidity (MM) management and disease prevention, our recent survey of 1,153 Appalachian residents aged 50 to 76 documented that individuals with MM were more likely to obtain colorectal cancer screening (CRCS) than those without MM. Nearly two thirds of respondents obtained CRCS, and the more MM, the greater the likelihood of screening. To gain insight into this relationship, we conducted nine focus groups, six with providers and three with patients. Three main explanations emerged: (a) patients' MM increases providers' vigilance for other health vulnerabilities; (b) having MM increases patients' own vigilance; and (c) patients' vigilance may stem from experiencing more symptoms, having a family history of cancer, and having successfully obtained health care. More frequent contact with health care providers appears to encourage preventive referral, especially in low-income populations that otherwise may not receive such counselling. We highlight participant recommendations to improve MM management and prevention. PMID:24652900

  9. Patient and Provider Perspectives on the Relationship Between Multiple Morbidity Management and Disease Prevention

    PubMed Central

    Schoenberg, Nancy E.; Tarasenko, Yelena N.; Bardach, Shoshana H.; Fleming, Steven T.

    2016-01-01

    Despite competing demands of multiple morbidity (MM) management and disease prevention, our recent survey of 1,153 Appalachian residents aged 50 to 76 documented that individuals with MM were more likely to obtain colorectal cancer screening (CRCS) than those without MM. Nearly two thirds of respondents obtained CRCS, and the more MM, the greater the likelihood of screening. To gain insight into this relationship, we conducted nine focus groups, six with providers and three with patients. Three main explanations emerged: (a) patients’ MM increases providers’ vigilance for other health vulnerabilities; (b) having MM increases patients’ own vigilance; and (c) patients’ vigilance may stem from experiencing more symptoms, having a family history of cancer, and having successfully obtained health care. More frequent contact with health care providers appears to encourage preventive referral, especially in low-income populations that otherwise may not receive such counselling. We highlight participant recommendations to improve MM management and prevention. PMID:24652900

  10. Identifying the Non-recurrent Laryngeal Nerve: Preventing a Major Risk of Morbidity During Thyroidectomy

    PubMed Central

    Mahmodlou, Rahim; Aghasi, Mohammad Reza; Sepehrvand, Nariman

    2013-01-01

    Non-recurrent laryngeal nerve (NRLN) is a rare anomaly which is reported in 0.3%-0.8% of people on the right side and in 0.004% (extremely rare) on the left side. Damage to this nerve during the surgical procedure may lead to severe iatrogenic morbidity and should therefore be prevented from being damaged. The best way to avoid this damage to the nerve is to identify the nerve with a systematic diligent dissection based on usual anatomical landmarks and awareness about the possibility of their existence. Hereby, we are going to present a 26-year-old woman, a case of NRLN on the right side which was identified during thyroidectomy. The nervous anomaly was accompanied with vascular abnormality which was confirmed by computerized tomography (CT) angiography, post-operatively. PMID:23543847

  11. Skin microbes on frogs prevent morbidity and mortality caused by a lethal skin fungus.

    PubMed

    Harris, Reid N; Brucker, Robert M; Walke, Jenifer B; Becker, Matthew H; Schwantes, Christian R; Flaherty, Devon C; Lam, Brianna A; Woodhams, Douglas C; Briggs, Cheryl J; Vredenburg, Vance T; Minbiole, Kevin P C

    2009-07-01

    Emerging infectious diseases threaten human and wildlife populations. Altered ecological interactions between mutualistic microbes and hosts can result in disease, but an understanding of interactions between host, microbes and disease-causing organisms may lead to management strategies to affect disease outcomes. Many amphibian species in relatively pristine habitats are experiencing dramatic population declines and extinctions due to the skin disease chytridiomycosis, which is caused by the chytrid fungus Batrachochytrium dendrobatidis. Using a randomized, replicated experiment, we show that adding an antifungal bacterial species, Janthinobacterium lividum, found on several species of amphibians to the skins of the frog Rana muscosa prevented morbidity and mortality caused by the pathogen. The bacterial species produces the anti-chytrid metabolite violacein, which was found in much higher concentrations on frog skins in the treatments where J. lividum was added. Our results show that cutaneous microbes are a part of amphibians' innate immune system, the microbial community structure on frog skins is a determinant of disease outcome and altering microbial interactions on frog skins can prevent a lethal disease outcome. A bioaugmentation strategy may be an effective management tool to control chytridiomycosis in amphibian survival assurance colonies and in nature. PMID:19322245

  12. Amniotic Fluid Embolism (AFE) in China: Are maternal mortality and morbidity preventable?

    PubMed

    Mo, Xiuting; Feng, Aihua; Liu, Xiaoyan; Tobe, Ruoyan Gai

    2014-08-01

    A case of hospital-patient conflict has occurred in China that has lifted billows in the public and highlighted the lethality of amniotic fluid embolism (AFE). AFE is a rare but severe obstetric complication with high maternal mortality and morbidity. Globally, the incidence of AFE is estimated to be approximately 2 to 6 per 100,000 deliveries. The maternal mortality rate (MMR) attributable to AFE ranges between 0.5 to 1.7 deaths per 100,000 deliveries in the developed world and 1.9 to 5.9 deaths per 100,000 deliveries in the developing world. In developed countries, AFE often accounts for a leading cause of maternal mortality; whereas the proportion of maternal death caused by AFE tends to be not as dominant compared to common perinatal complications in developing countries. With the mechanism remaining to be elucidated, AFE can neither be predicted nor prevented even in developed countries. Treatment requires a set of highly intensive advanced emergency obstetric care, challenging obstetric care in developing countries. Although this complication is currently far from preventable, China has potential to improve the prognosis of AFE by strengthening the emergency obstetric care system. PMID:25364652

  13. Bone targeted therapies for the prevention of skeletal morbidity in men with prostate cancer

    PubMed Central

    Saylor, Philip J

    2014-01-01

    Men with prostate cancer suffer substantially from bone-related complications. Androgen deprivation therapy itself is a cause of loss of bone mineral density and is associated with an increased incidence of osteoporotic fractures. In advanced disease, bone is by far the most common site of metastasis. Complications of bone metastases prominently include pain and the potential for skeletal events such as spinal cord compression and pathologic fractures. Elevated osteoclast activity is an important aspect of the pathophysiology of both treatment-related osteoporosis and skeletal complications due to metastases. The osteoclast is therefore a therapeutic target. Denosumab is a fully human monoclonal antibody to receptor activator of nuclear factor-κ-B ligand that was designed to potently inhibit osteoclast activity and is the central focus of this review. Bisphosphonates, radiopharmaceuticals and systemically-active hormonal agents such as abiraterone acetate and enzalutamide have each been shown to improve skeletal morbidity in specific clinical situations. Denosumab is the only agent that has been shown to prevent osteoporotic fractures in men receiving androgen deprivation therapy and at elevated risk for fracture. It has also demonstrated superiority to the potent bisphosphonate zoledronic acid for the prevention of skeletal-related events in men with castration-resistant prostate cancer metastatic to bone. Efficacy and toxicity data will be discussed. PMID:24435057

  14. Is it possible to prevent morbidity on post cardiovascular surgery applying low level laser therapy?

    NASA Astrophysics Data System (ADS)

    Pinto, Nathali C.; Baptista, Ivany Machado d. C.; Pereira, Mara Helena C.; Serrão, Nelson F.; Pomerantzeff, Pablo M. A.; Chavantes, Maria Cristina

    2014-03-01

    Background and Objective: Complications following cardiovascular surgery incision are common in mediastinitis and wound dehiscence form, a 47% mortality rate remaining. Low Level Laser Therapy (LLLT) has been employed mainly to its effectiveness analgesic and anti-inflammatory actions, aiding the tissue repair process. The aim of this study was to evaluate infrared LLLT onto surgical incision in patients submitted to cardiovascular surgery. Materials and Methods: 40 patients were divided in two groups: Placebo Group (G1) - conventional therapy + "Laser pointer" and Laser Group (G2) - conventional therapy + Infrared Laser irradiation on surgical incision. Diode Laser was employed, C.W. mode, around the surgical wound bed, on immediate Post Operative (PO), 1st PO and 3rd PO with the following parameters: wavelength (λ): 830nm, P=35mW, E=0,75J. Results: G2 didn't present any complication and 5% of patients in G1 developed incision dehiscence and infection. On 7thPO, still a large amount of G1 patients showed pain and unquestionable inflammatory signs surrounding the surgical wound, when compared to G2. Besides, hospital stay in Laser Group was 2 times shorter than in Placebo Group (p-value=0.001). Conclusion: Infrared Laser denoted to be safe and exceptionally valuable tools in preventing morbidities on post cardiovascular surgeries.

  15. Children can't fly: a program to prevent childhood morbidity and mortality from window falls.

    PubMed Central

    Spiegel, C N; Lindaman, F C

    1977-01-01

    "Children Can't Fly" is a health education program developed by the New York City Department of Health to combat the high incidence of child mortality and morbidity due to falls from windows. The success of the program, begun in 1972, in drastically reducing death and injury persuaded the New York City Board of Health to amend the Health Code in 1976 to require that landlords provide window guards in apartments where children ten years old and younger reside. The law is the first and only one of its kind in the nation. The program has four major components: 1) reporting of falls by hospital emergency rooms and police precincts, followed up by counseling, referral, and data collecting by public health nurses; 2) a media campaign to inform the public and elevate their awareness of the hazards; 3) community education for prevention through door-to-door hazard identification, counseling by outreach workers, community organization efforts with schools, tenant groups, clinics, churches, health care providers, etc; 4) provision of free, easily installed window guards to families with young children living in high-risk areas. Significant reduction in falls resulted, particularly in the Bronx, where reported falls declined 50 percent from 1973 to 1975. The program is one solution to an urgent urban problem which other cities might consider to avert the loss of life and limb, and the corollary financial burden for hospitalization, rehabilitation, and maintenance of the injured and permanently disabled. PMID:596496

  16. Children can't fly: a program to prevent childhood morbidity and mortality from window falls

    PubMed Central

    Spiegel, Charlotte N; Lindaman, Francis C

    1995-01-01

    `Children Can't Fly' is a health education program developed by the New York City Department of Health to combat the high incidence of child mortality and morbidity due to falls from windows. The success of the program, begun in 1972, in drastically reducing death and injury persuaded the New York City Board of Health to amend the Health Code in 1976 to require that landlords provide window guards in apartments where children 10 years old and younger reside. The law is the first and only one of its kind in the nation. The program has four major components: (1) reporting of falls by hospital emergency rooms and police precincts, followed up by counseling, referral and data collecting by public health nurses; (2) a media campaign to inform the public and elevate their awareness of the hazards; (3) community education for prevention through door-to-door hazard identification, counseling by outreach workers, community organization efforts with schools, tenant groups, clinics, churches, health care providers, etc; (4) provision of free, easily installed window guards to families with young children living in high-risk areas. Significant reduction in falls resulted, particularly in the Bronx, where reported falls declined 50% from 1973 to 1975. The program is one solution to an urgent urban problem which other cities might consider to avert the loss of life and limb, and the corollary financial burden for hospitalization, rehabilitation and maintenance of the injured and permanently disabled. PMID:9346026

  17. Landmark learning by juvenile salamanders (Ambystoma maculatum).

    PubMed

    Heuring, Whitney L; Mathis, Alicia

    2014-10-01

    Learning to use a landmark as a beacon to locate resources is one of the simplest forms of spatial learning. We tested whether landmark learning occurs in a semifossorial salamander that migrates annually to breeding ponds as adults. Juvenile spotted salamanders (Ambystoma maculatum) were tested in square containers with a plastic feeding dish in each corner, and a piece of earthworm was placed in one randomly-chosen dish. For landmark-trained salamanders, a rock was placed beside the dish containing the prey. For control salamanders, the rock was placed beside a randomly selected feeding dish. Each salamander was trained once every 2 days for 30 days. Significantly more landmark-trained salamanders than control salamanders entered the landmark area first, and landmark-trained individuals had faster latencies to enter the landmark area and longer stay-times. These results suggest that spotted salamanders are able to locate resources by associating their positions with landmarks. PMID:25444775

  18. Woodland salamander responses to a shelterwood harvest-prescribed burn silvicultural treatment within Appalachian mixed-oak forests

    USGS Publications Warehouse

    Ford, W. Mark; Mahoney, Kathleen R.; Russell, Kevin R.; Rodrigue, Jane L.; Riddle, Jason D.; Schuler, Thomas M.; Adams, Mary Beth

    2015-01-01

    Forest management practices that mimic natural canopy disturbances, including prescribed fire and timber harvests, may reduce competition and facilitate establishment of favorable vegetative species within various ecosystems. Fire suppression in the central Appalachian region for almost a century has contributed to a transition from oak-dominated to more mesophytic, fire-intolerant forest communities. Prescribed fire coupled with timber removal is currently implemented to aid in oak regeneration and establishment but responses of woodland salamanders to this complex silvicultural system is poorly documented. The purpose of our research was to determine how woodland salamanders respond to shelterwood harvests following successive burns in a central Appalachian mixed-oak forest. Woodland salamanders were surveyed using coverboard arrays in May, July, and August–September 2011 and 2012. Surveys were conducted within fenced shelterwood-burn (prescribed fires, shelterwood harvest, and fencing to prevent white-tailed deer [Odocoileus virginianus] herbivory), shelterwood-burn (prescribed fires and shelterwood harvest), and control plots. Relative abundance was modeled in relation to habitat variables measured within treatments for mountain dusky salamanders (Desmognathus ochrophaeus), slimy salamanders (Plethodon glutinosus), and eastern red-backed salamanders (Plethodon cinereus). Mountain dusky salamander relative abundance was positively associated with canopy cover and there were significantly more individuals within controls than either shelterwood-burn or fenced shelterwood-burn treatments. Conversely, habitat variables associated with slimy salamanders and eastern red-backed salamanders did not differ among treatments. Salamander age-class structure within controls did not differ from shelterwood-burn or fenced shelterwood-burn treatments for any species. Overall, the woodland salamander assemblage remained relatively intact throughout the shelterwoodburn

  19. "ANEIDES AENEUS" (GREEN SALAMANDER). DISPERSAL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aneides aeneus inhabits cliffs and rockface outcrops at elevations <1340 m in mountainous forests from southwestern Pennsylvania to extreme northeastern Mississippi (Petranka 1998. Salamanders of the United States and Canada. Smithsonian Institution Press, Washington D.C. 587pp). Populations are ...

  20. Preventive zinc supplementation in developing countries: impact on mortality and morbidity due to diarrhea, pneumonia and malaria

    PubMed Central

    2011-01-01

    Background Zinc deficiency is commonly prevalent in children in developing countries and plays a role in decreased immunity and increased risk of infection. Preventive zinc supplementation in healthy children can reduce mortality due to common causes like diarrhea, pneumonia and malaria. The main objective was to determine all-cause mortality and cause-specific mortality and morbidity in children under five in developing countries for preventive zinc supplementation. Data sources/ review methods A literature search was carried out on PubMed, the Cochrane Library and the WHO regional databases to identify RCTs on zinc supplementation for greater than 3 months in children less than 5 years of age in developing countries and its effect on mortality was analyzed. Results The effect of preventive zinc supplementation on mortality was given in eight trials, while cause specific mortality data was given in five of these eight trials. Zinc supplementation alone was associated with a statistically insignificant 9% (RR = 0.91; 95% CI: 0.82, 1.01) reduction in all cause mortality in the intervention group as compared to controls using a random effect model. The impact on diarrhea-specific mortality of zinc alone was a non-significant 18% reduction (RR = 0.82; 95% CI: 0.64, 1.05) and 15% for pneumonia-specific mortality (RR = 0.85; 95% CI: 0.65, 1.11). The incidence of diarrhea showed a 13% reduction with preventive zinc supplementation (RR = 0.87; 95% CI: 0.81, 0.94) and a 19% reduction in pneumonia morbidity (RR = 0.81; 95% CI: 0.73, 0.90). Keeping in mind the direction of effect of zinc supplementation in reducing diarrhea and pneumonia related morbidity and mortality; we considered all the outcomes for selection of effectiveness estimate for inclusion in the LiST model. After application of the CHERG rules with consideration to quality of evidence and rule # 6, we used the most conservative estimates as a surrogate for mortality. We, therefore, conclude that zinc

  1. Lifestyle Modification for the Prevention of Morbidity and Mortality in Adult Congenital Heart Disease.

    PubMed

    Rosenthal, Todd M; Leung, Steven T; Ahmad, Raza; Young, Thomas; Lavie, Carl J; Moodie, Douglas S; Shah, Sangeeta

    2016-01-01

    Patients with adult congenital heart disease are now living longer due to the advancements in medicine. As such, these patients are now experiencing morbidities that are commonly seen in the general population such as myocardial infarction, heart failure, and arrhythmias. Often times these problems can be attributed to the underlying adult congenital heart disease; however, a patient making poor lifestyle choices only compounds their risk for these life-threatening comorbidities. The aim of this article is to propose recommendations for health care providers to follow with this specific patient population. These recommendations encompass the importance of proper caloric intake, methods of weight loss (including behavioral therapy, drugs, and surgeries), practical recommendations for physical activity, and the implications of substance abuse. Being proactive and addressing important lifestyle choices in this population can reduce comorbidities and, therefore, medical cost. PMID:26931766

  2. Heterogeneity of Nasolabial Flap- Role in Prevention of Morbidity Associated with Reconstruction of Orofacial Defects.

    PubMed

    Abida, Roshni; Ayyallil, Muhamed Sajid

    2015-09-01

    Reconstructive technique after surgical excision of malignancy in orofacial region should be planned in preoperative period itself. Surgery is the preferred modality of treatment if the tumour is small and located in an accessible area. Nasolabial flap is a versatile flap which is well suited to cover small defects in maxillofacial region. Nasolabial flap can be used as an alternative to other distant pedicled flaps in selected cases. A retrospective analysis of 12 cases of oral cancer treated with primary excision and reconstruction using nasolabial flap was done. Patients who underwent resection of tumour and reconstruction with nasolabial flap in selected cases reduced the morbidity associated with Distant pedicled flaps. Two selected cases are described in detail. PMID:26501027

  3. Perioperative beta-blockers for preventing surgery-related mortality and morbidity.

    PubMed

    Bolton, Nerys

    2016-03-01

    For many patients any type of surgical invention can increase their stress response which can make the body vulnerable to untoward outcomes. An extreme consequence of the stress response is death with other responses including heart attacks and stroke, to impacting on the patients' postoperative reviver such as their psychological status and pain recovery. Therefore there is a need to consider the attenuation of the perioperative stress response through the use of drugs such as beta-blockers. These drugs have been shown to reduce the heart rate and lower the patients' blood pressure. Although this is a desired result in trying to eliminate the effects of the stress response it can also have the opposite effect on reducing the patients' blood pressure and pulse to a point where the patients suffers ill effects such as stroke or death. Therefore it is vital to understand the influence of beta-blockers and their ability to influence perioperative cardiovascular morbidity and mortality. PMID:27149829

  4. Negative pressure pulmonary oedema following tracheal tube obstruction in a paediatric patient: a preventable anaesthesia related morbidity.

    PubMed

    Imarengiaye, C O; Ogunsakin, A

    2003-09-01

    The purpose of this study is to describe negative pressure pulmonary oedema due to undetected tracheal tube obstruction in a paediatric patient. A healthy 6 week-old scheduled for release of tongue-tie under general anaesthesia was noticed to be diagnosed at the preparation of the surgical site. The patient was quickly assessed, and ventilation with 100% oxygen was commenced. The heart sounds were still present. Two minutes later, pink frothy secretion was noticed in the lumen of the tracheal tube. Assisted manual ventilation was continued for about 3 hours in the intensive care unit (ICU). Clinical examination after 8 hours of oxygen therapy indicated stable vital signs and was discharged to the ward. Undetected tracheal obstruction due to unsupervised patient positioning may result in negative pressure pulmonary oedema in a paediatric patient. Improved communication between the surgical and the anaesthetic teams may prevent this morbidity. PMID:14692058

  5. 'Salamander plague' on Britain's doorstep.

    PubMed

    Mills, Georgina

    2015-01-24

    Chytridiomycosis can cause mass declines in amphibians, and the chytrid fungus Batrachochytrium dendrobatidis is the classic cause of this disease. However, recently, a second strain of chytrid fungus has emerged in Europe, resulting in major declines in fire salamanders. The Zoological Society of London (ZSL) discussed this, and the implications for the UK, at a meeting in December in London. Georgina Mills reports. PMID:25614547

  6. Earliest known crown-group salamanders.

    PubMed

    Gao, Ke-Qin; Shubin, Neil H

    2003-03-27

    Salamanders are a model system for studying the rates and patterns of the evolution of new anatomical structures. Recent discoveries of abundant Late Jurassic and Early Cretaceous salamanders are helping to address these issues. Here we report the discovery of well-preserved Middle Jurassic salamanders from China, which constitutes the earliest known record of crown-group urodeles (living salamanders and their closest relatives). The new specimens are from the volcanic deposits of the Jiulongshan Formation (Bathonian), Inner Mongolia, China, and represent basal members of the Cryptobranchidae, a family that includes the endangered Asian giant salamander (Andrias) and the North American hellbender (Cryptobranchus). These fossils document a Mesozoic record of the Cryptobranchidae, predating the previous record of the group by some 100 million years. This discovery provides evidence to support the hypothesis that the divergence of the Cryptobranchidae from the Hynobiidae had taken place in Asia before the Middle Jurassic period. PMID:12660782

  7. Ambystoma maculatum (spotted salamander). Reproduction

    USGS Publications Warehouse

    Glorioso, Brad M.; Waddle, Hardin; Hefner, Jeromi

    2012-01-01

    The Spotted Salamander is a wide-ranging salamander of the eastern United States that typically breeds in winter or early spring in ephemeral pools in lowland forests. Ambystoma maculatum is known to deposit 2-4 egg masses per year, each containing 1-250 eggs. As part of ongoing research into the ecology and reproductive biology of Spotted Salamanders in the Kisatchie District of Kisatchie National Forest in Natchitoches Parish, Louisiana, USA, we have been counting the number of embryos per egg mass. We captured seven female A. maculatum in a small pool, six of which were still gravid. We took standard measurements, including SVL, and then implanted a Passive Integrated Transponder (PIT tag) into each adult female as was the protocol. About an hour after processing these animals we marked new A. maculatum egg masses found in the same small pool using PVC pin flags pushed carefully through the outer jelly. We did not have enough time to process them that evening, and it was not until a few days later that we photographed those masses. We discovered that one of the masses contained a PIT tag in the outer jelly that corresponded to one of the six gravid females that were marked that same evening. To our knowledge, this is the first report of PIT tags being the means, albeit coincidentally, by which a particular egg mass of Ambystoma maculatum has been assigned to a particular female. For our purposes, losing the PIT tag from the adult female is counter to the goals of our study of this population, and we will no longer be implanting PIT tags into gravid females.

  8. Late Jurassic salamanders from northern China.

    PubMed

    Gao, K Q; Shubin, N H

    2001-03-29

    With ten extant families, salamanders (urodeles) are one of the three major groups of modern amphibians (lissamphibians). Extant salamanders are often used as a model system to assess fundamental issues of developmental, morphological and biogeographical evolution. Unfortunately, our understanding of these issues has been hampered by the paucity of fossil evidence available to assess the early history of the group. Here we report the discovery of an extraordinary sample of salamander fossils, some with rare soft-tissue impressions, from the Upper Jurassic of China. With over 500 articulated specimens, this assemblage documents the morphological diversity of early urodeles and includes larvae and adults of both neotenic and metamorphosed taxa. Phylogenetic analysis confirms that these salamanders are primitive, and reveals that all basal salamander clades have Asian distributions. This is compelling evidence for an Asian origin of Recent salamanders, as well as for an extensive and early radiation of several major lineages. These discoveries show that the evolution of salamanders has involved phylogenetic and ecological diversification around a body plan that has remained fundamentally stable for over 150 million years. PMID:11279493

  9. Prebiotic and Probiotic Fortified Milk in Prevention of Morbidities among Children: Community-Based, Randomized, Double-Blind, Controlled Trial

    PubMed Central

    Sazawal, Sunil; Dhingra, Usha; Hiremath, Girish; Sarkar, Archana; Dhingra, Pratibha; Dutta, Arup; Verma, Priti; Menon, Venugopal P.; Black, Robert E.

    2010-01-01

    Background Recent reviews suggest common infectious diseases continue to be a major cause of death among preschool children in developing countries. Identification of feasible strategies to combat this disease burden is an important public health need. We evaluated the efficacy of adding prebiotic oligosaccharide and probiotic Bifidobacterium lactis HN019 to milk, in preventing diarrhea, respiratory infections and severe illnesses, in children aged 1–4 years as part of a four group study design, running two studies simultaneously. Methods and Findings In a community based double-masked, randomized controlled trial, children 1–3 years of age, willing to participate, were randomly allocated to receive either control milk (Co; n = 312) or the same milk fortified with 2.4 g/day of prebiotic oligosaccharide and 1.9×107 colony forming unit (c.f.u)/day of probiotic Bifidobacterium lactis HN019 (PP; n = 312). Children were followed up for 1 year providing data for 1–4 years. Biweekly household surveillance was conducted to gather information on compliance and morbidity. Both study groups were comparable at baseline; compliance to intervention was similar. Overall, there was no effect of prebiotic and probiotic on diarrhea (6% reduction, 95% Confidence Interval [CI]: −1 to 12%; p = 0.08). Incidence of dysentery episodes was reduced by 21% (95% CI: 0 to 38%; p = 0.05). Incidence of pneumonia was reduced by 24% (95% CI: 0 to 42%; p = 0.05) and severe acute lower respiratory infection (ALRI) by 35% (95% CI: 0 to 58%; p = 0.05). Compared to children in Co group, children in PP group had 16% (95% CI: 5 to 26%, p = 0.004) and 5% (95% CI: 0 to 10%; p = 0.05) reduction in days with severe illness and high fever respectively. Conclusions/Significance Milk can be a good medium for delivery of prebiotic and probiotic and resulted in significant reduction of dysentery, respiratory morbidity and febrile illness. Overall, impact of diarrhea was

  10. Cholesterol-independent effects of atorvastatin prevent cardiovascular morbidity and mortality in a mouse model of atherosclerotic plaque rupture.

    PubMed

    Roth, Lynn; Rombouts, Miche; Schrijvers, Dorien M; Martinet, Wim; De Meyer, Guido R Y

    2016-05-01

    Because cholesterol-independent effects of statins are difficult to determine in patients, we studied these pleiotropic effects in apolipoprotein E-deficient (ApoE(-/-)) mice with a mutation in the fibrillin-1 gene (Fbn1(C1039G+/-)). These mice develop exacerbated atherosclerosis and spontaneous plaque ruptures, accompanied by myocardial infarctions (MI) and sudden death. ApoE(-/-)Fbn1(C1039G+/-) mice were fed a Western diet (WD). At week 10 of WD, mice were divided in a control (WD), atorvastatin (10mg/kg/day + WD) and cholesterol withdrawal group (cholW, normal chow). The latter was included to compare the effects of atorvastatin with dietary lipid lowering. Fifteen weeks later, the mice were sacrificed. CholW, but not atorvastatin, reduced plasma cholesterol. Survival increased from 50% to 90% both in cholW and atorvastatin treated mice. CholW as well as atorvastatin treatment increased plaque collagen and fibrous cap thickness, but they did not affect the amount of plaque macrophages and T cells. MMP-2 and MMP-9 activity was significantly lower and the expression of MMP-12, TNF-α and IL-1β was strongly reduced in both treatment groups. Blood monocytes and neutrophils returned to baseline levels (ApoE(-/-) mice before the onset of atherosclerosis). Importantly, atorvastatin but not cholW significantly reduced coronary stenosis (from 50 to 28%) and the occurrence of MI (from 43 to 10%). In conclusion, independent of cholesterol lowering, atorvastatin significantly reduced mortality, plaque vulnerability and inflammation to the same extent as cholW. In addition, atorvastatin but not cholW reduced coronary stenosis and the occurrence of MI. These data unequivocally illustrate the significance of the pleiotropic effects of atorvastatin in the prevention of cardiovascular morbidity and mortality. PMID:26826559

  11. Conservation assessment for the Siskiyou Mountains salamander and Scott Bar salamander in northern California.

    SciTech Connect

    Vinikour, W. S.; LaGory, K. E.; Adduci, J. J.; Environmental Science Division

    2006-10-20

    The purpose of this conservation assessment is to summarize existing knowledge regarding the biology and ecology of the Siskiyou Mountains salamander and Scott Bar salamander, identify threats to the two species, and identify conservation considerations to aid federal management for persistence of the species. The conservation assessment will serve as the basis for a conservation strategy for the species.

  12. ARE SALAMANDERS USEFUL INDICATORS OF HYDROLOGIC PERMANENCE IN HEADWATER STREAMS?

    EPA Science Inventory

    Regulatory agencies need appropriate indicators of stream permanence to aid in jurisdictional determinations for headwater streams. We evaluated salamanders as permanence indicators because they are often abundant in fishless headwaters. Salamander and habitat data were collect...

  13. LTR Retrotransposons Contribute to Genomic Gigantism in Plethodontid Salamanders

    PubMed Central

    Sun, Cheng; Shepard, Donald B.; Chong, Rebecca A.; López Arriaza, José; Hall, Kathryn; Castoe, Todd A.; Feschotte, Cédric; Pollock, David D.; Mueller, Rachel Lockridge

    2012-01-01

    Among vertebrates, most of the largest genomes are found within the salamanders, a clade of amphibians that includes 613 species. Salamander genome sizes range from ∼14 to ∼120 Gb. Because genome size is correlated with nucleus and cell sizes, as well as other traits, morphological evolution in salamanders has been profoundly affected by genomic gigantism. However, the molecular mechanisms driving genomic expansion in this clade remain largely unknown. Here, we present the first comparative analysis of transposable element (TE) content in salamanders. Using high-throughput sequencing, we generated genomic shotgun data for six species from the Plethodontidae, the largest family of salamanders. We then developed a pipeline to mine TE sequences from shotgun data in taxa with limited genomic resources, such as salamanders. Our summaries of overall TE abundance and diversity for each species demonstrate that TEs make up a substantial portion of salamander genomes, and that all of the major known types of TEs are represented in salamanders. The most abundant TE superfamilies found in the genomes of our six focal species are similar, despite substantial variation in genome size. However, our results demonstrate a major difference between salamanders and other vertebrates: salamander genomes contain much larger amounts of long terminal repeat (LTR) retrotransposons, primarily Ty3/gypsy elements. Thus, the extreme increase in genome size that occurred in salamanders was likely accompanied by a shift in TE landscape. These results suggest that increased proliferation of LTR retrotransposons was a major molecular mechanism contributing to genomic expansion in salamanders. PMID:22200636

  14. Salamander occupancy in headwater stream networks

    USGS Publications Warehouse

    Grant, E.H.C.; Green, L.E.; Lowe, W.H.

    2009-01-01

    1. Stream ecosystems exhibit a highly consistent dendritic geometry in which linear habitat units intersect to create a hierarchical network of connected branches. 2. Ecological and life history traits of species living in streams, such as the potential for overland movement, may interact with this architecture to shape patterns of occupancy and response to disturbance. Specifically, large-scale habitat alteration that fragments stream networks and reduces connectivity may reduce the probability a stream is occupied by sensitive species, such as stream salamanders. 3. We collected habitat occupancy data on four species of stream salamanders in first-order (i.e. headwater) streams in undeveloped and urbanised regions of the eastern U.S.A. We then used an information-theoretic approach to test alternative models of salamander occupancy based on a priori predictions of the effects of network configuration, region and salamander life history. 4. Across all four species, we found that streams connected to other first-order streams had higher occupancy than those flowing directly into larger streams and rivers. For three of the four species, occupancy was lower in the urbanised region than in the undeveloped region. 5. These results demonstrate that the spatial configuration of stream networks within protected areas affects the occurrences of stream salamander species. We strongly encourage preservation of network connections between first-order streams in conservation planning and management decisions that may affect stream species.

  15. Data congruence, paedomorphosis and salamanders

    PubMed Central

    Struck, Torsten H

    2007-01-01

    Background The retention of ancestral juvenile characters by adult stages of descendants is called paedomorphosis. However, this process can mislead phylogenetic analyses based on morphological data, even in combination with molecular data, because the assessment if a character is primary absent or secondary lost is difficult. Thus, the detection of incongruence between morphological and molecular data is necessary to investigate the reliability of simultaneous analyses. Different methods have been proposed to detect data congruence or incongruence. Five of them (PABA, PBS, NDI, LILD, DRI) are used herein to assess incongruence between morphological and molecular data in a case study addressing salamander phylogeny, which comprises several supposedly paedomorphic taxa. Therefore, previously published data sets were compiled herein. Furthermore, two strategies ameliorating effects of paedomorphosis on phylogenetic studies were tested herein using a statistical rigor. Additionally, efficiency of the different methods to assess incongruence was analyzed using this empirical data set. Finally, a test statistic is presented for all these methods except DRI. Results The addition of morphological data to molecular data results in both different positions of three of the four paedomorphic taxa and strong incongruence, but treating the morphological data using different strategies ameliorating the negative impact of paedomorphosis revokes these changes and minimizes the conflict. Of these strategies the strategy to just exclude paedomorphic character traits seem to be most beneficial. Of the three molecular partitions analyzed herein the RAG1 partition seems to be the most suitable to resolve deep salamander phylogeny. The rRNA and mtDNA partition are either too conserved or too variable, respectively. Of the different methods to detect incongruence, the NDI and PABA approaches are more conservative in the indication of incongruence than LILD and PBS. Conclusion

  16. Invasive Asian Earthworms Negatively Impact Keystone Terrestrial Salamanders.

    PubMed

    Ziemba, Julie L; Hickerson, Cari-Ann M; Anthony, Carl D

    2016-01-01

    Asian pheretimoid earthworms (e.g. Amynthas and Metaphire spp.) are invading North American forests and consuming the vital detrital layer that forest floor biota [including the keystone species Plethodon cinereus (Eastern Red-backed Salamander)], rely on for protection, food, and habitat. Plethodon cinereus population declines have been associated with leaf litter loss following the invasion of several exotic earthworm species, but there have been few studies on the specific interactions between pheretimoid earthworms and P. cinereus. Since some species of large and active pheretimoids spatially overlap with salamanders beneath natural cover objects and in detritus, they may distinctively compound the negative consequences of earthworm-mediated resource degradation by physically disturbing important salamander activities (foraging, mating, and egg brooding). We predicted that earthworms would exclude salamanders from high quality microhabitat, reduce foraging efficiency, and negatively affect salamander fitness. In laboratory trials, salamanders used lower quality microhabitat and consumed fewer flies in the presence of earthworms. In a natural field experiment, conducted on salamander populations from "non-invaded" and "pheretimoid invaded" sites in Ohio, salamanders and earthworms shared cover objects ~60% less than expected. Earthworm abundance was negatively associated with juvenile and male salamander abundance, but had no relationship with female salamander abundance. There was no effect of pheretimoid invasion on salamander body condition. Juvenile and non-resident male salamanders do not hold stable territories centered beneath cover objects such as rocks or logs, which results in reduced access to prey, greater risk of desiccation, and dispersal pressure. Habitat degradation and physical exclusion of salamanders from cover objects may hinder juvenile and male salamander performance, ultimately reducing recruitment and salamander abundance following Asian

  17. Invasive Asian Earthworms Negatively Impact Keystone Terrestrial Salamanders

    PubMed Central

    Ziemba, Julie L.

    2016-01-01

    Asian pheretimoid earthworms (e.g. Amynthas and Metaphire spp.) are invading North American forests and consuming the vital detrital layer that forest floor biota [including the keystone species Plethodon cinereus (Eastern Red-backed Salamander)], rely on for protection, food, and habitat. Plethodon cinereus population declines have been associated with leaf litter loss following the invasion of several exotic earthworm species, but there have been few studies on the specific interactions between pheretimoid earthworms and P. cinereus. Since some species of large and active pheretimoids spatially overlap with salamanders beneath natural cover objects and in detritus, they may distinctively compound the negative consequences of earthworm-mediated resource degradation by physically disturbing important salamander activities (foraging, mating, and egg brooding). We predicted that earthworms would exclude salamanders from high quality microhabitat, reduce foraging efficiency, and negatively affect salamander fitness. In laboratory trials, salamanders used lower quality microhabitat and consumed fewer flies in the presence of earthworms. In a natural field experiment, conducted on salamander populations from “non-invaded” and “pheretimoid invaded” sites in Ohio, salamanders and earthworms shared cover objects ~60% less than expected. Earthworm abundance was negatively associated with juvenile and male salamander abundance, but had no relationship with female salamander abundance. There was no effect of pheretimoid invasion on salamander body condition. Juvenile and non-resident male salamanders do not hold stable territories centered beneath cover objects such as rocks or logs, which results in reduced access to prey, greater risk of desiccation, and dispersal pressure. Habitat degradation and physical exclusion of salamanders from cover objects may hinder juvenile and male salamander performance, ultimately reducing recruitment and salamander abundance

  18. The First Salamander Defensin Antimicrobial Peptide

    PubMed Central

    Jiang, Ke; Rong, Mingqiang; Lai, Ren

    2013-01-01

    Antimicrobial peptides have been widely identified from amphibian skins except salamanders. A novel antimicrobial peptide (CFBD) was isolated and characterized from skin secretions of the salamander, Cynops fudingensis. The cDNA encoding CFBD precursor was cloned from the skin cDNA library of C. fudingensis. The precursor was composed of three domains: signal peptide of 17 residues, mature peptide of 41 residues and intervening propeptide of 3 residues. There are six cysteines in the sequence of mature CFBD peptide, which possibly form three disulfide-bridges. CFBD showed antimicrobial activities against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli. This peptide could be classified into family of β-defensin based on its seqeuence similarity with β-defensins from other vertebrates. Evolution analysis indicated that CFBD was close to fish β-defensin. As far as we know, CFBD is the first β-defensin antimicrobial peptide from salamanders. PMID:24386139

  19. Evolution of Gigantism in Amphiumid Salamanders

    PubMed Central

    Bonett, Ronald M.; Chippindale, Paul T.; Moler, Paul E.; Van Devender, R. Wayne; Wake, David B.

    2009-01-01

    The Amphiumidae contains three species of elongate, permanently aquatic salamanders with four diminutive limbs that append one, two, or three toes. Two of the species, Amphiuma means and A. tridactylum, are among the largest salamanders in the world, reaching lengths of more than one meter, whereas the third species (A. pholeter), extinct amphiumids, and closely related salamander families are relatively small. Amphiuma means and A. tridactylum are widespread species and live in a wide range of lowland aquatic habitats on the Coastal Plain of the southeastern United States, whereas A. pholeter is restricted to very specialized organic muck habitats and is syntopic with A. means. Here we present analyses of sequences of mitochondrial and nuclear loci from across the distribution of the three taxa to assess lineage diversity, relationships, and relative timing of divergence in amphiumid salamanders. In addition we analyze the evolution of gigantism in the clade. Our analyses indicate three lineages that have diverged since the late Miocene, that correspond to the three currently recognized species, but the two gigantic species are not each other's closest relatives. Given that the most closely related salamander families and fossil amphiumids from the Upper Cretaceous and Paleocene are relatively small, our results suggest at least two extreme changes in body size within the Amphuimidae. Gigantic body size either evolved once as the ancestral condition of modern amphiumas, with a subsequent strong size reduction in A. pholeter, or gigantism independently evolved twice in the modern species, A. means and A. tridactylum. These patterns are concordant with differences in habitat breadth and range size among lineages, and have implications for reproductive isolation and diversification of amphiumid salamanders. PMID:19461997

  20. Prevention of Tungiasis and Tungiasis-Associated Morbidity Using the Plant-Based Repellent Zanzarin: A Randomized, Controlled Field Study in Rural Madagascar

    PubMed Central

    Thielecke, Marlene; Raharimanga, Vaomalala; Rogier, Christophe; Stauss-Grabo, Manuela; Richard, Vincent; Feldmeier, Hermann

    2013-01-01

    Background Tungiasis, a parasitic skin disease caused by the female sand flea Tunga penetrans, is a prevalent condition in impoverished communities in the tropics. In this setting, the ectoparasitosis is associated with important morbidity. It causes disfigurement and mutilation of the feet. Feasible and effective treatment is not available. So far prevention is the only means to control tungiasis-associated morbidity. Methodology In two villages in Central Madagascar, we assessed the efficacy of the availability of closed shoes and the twice-daily application of a plant-based repellent active against sand fleas (Zanzarin) in comparison to a control group without intervention. The study population was randomized into three groups: shoe group, repellent group and control group and monitored for ten weeks. The intensity of infestation, the attack rate and the severity of tungiasis-associated morbidity were assessed every two weeks. Findings In the repellent group, the median attack rate became zero already after two weeks. The intensity of the infestation decreased constantly during the observation period and tungiasis-associated morbidity was lowered to an insignificant level. In the shoe group, only a marginal decrease in the intensity of infestation and in the attack rate was observed. At week 10, the intensity of infestation, the attack rate and the severity score for acute tungiasis remained significantly higher in the shoe group than in the repellent group. Per protocol analysis showed that the protective effect of shoes was closely related to the regularity with which shoes were worn. Conclusions Although shoes were requested by the villagers and wearing shoes was encouraged by the investigators at the beginning of the study, the availability of shoes only marginally influenced the attack rate of female sand fleas. The twice-daily application of a plant-based repellent active against sand fleas reduced the attack to zero and lowered tungiasis

  1. Effects of Timber Harvests and Silvicultural Edges on Terrestrial Salamanders

    PubMed Central

    MacNeil, Jami E.; Williams, Rod N.

    2014-01-01

    Balancing timber production and conservation in forest management requires an understanding of how timber harvests affect wildlife species. Terrestrial salamanders are useful indicators of mature forest ecosystem health due to their importance to ecosystem processes and sensitivity to environmental change. However, the effects of timber harvests on salamanders, though often researched, are still not well understood. To further this understanding, we used artificial cover objects to monitor the relative abundance of terrestrial salamanders for two seasons (fall and spring) pre-harvest and five seasons post-harvest in six forest management treatments, and for three seasons post-harvest across the edge gradients of six recent clearcuts. In total, we recorded 19,048 encounters representing nine species of salamanders. We observed declines in mean encounters of eastern red-backed salamanders (Plethodon cinereus) and northern slimy salamanders (P. glutinosus) from pre- to post-harvest in group selection cuts and in clearcuts. However, we found no evidence of salamander declines at shelterwoods and forested sites adjacent to harvests. Edge effects induced by recent clearcuts influenced salamanders for approximately 20 m into the forest, but edge influence varied by slope orientation. Temperature, soil moisture, and canopy cover were all correlated with salamander counts. Our results suggest silvicultural techniques that remove the forest canopy negatively affect salamander relative abundance on the local scale during the years immediately following harvest, and that the depth of edge influence of clearcuts on terrestrial salamanders is relatively shallow (<20 m). Small harvests (<4 ha) and techniques that leave the forest canopy intact may be compatible with maintaining terrestrial salamander populations across a forested landscape. Our results demonstrate the importance of examining species-specific responses and monitoring salamanders across multiple seasons and years

  2. Effects of timber harvests and silvicultural edges on terrestrial salamanders.

    PubMed

    MacNeil, Jami E; Williams, Rod N

    2014-01-01

    Balancing timber production and conservation in forest management requires an understanding of how timber harvests affect wildlife species. Terrestrial salamanders are useful indicators of mature forest ecosystem health due to their importance to ecosystem processes and sensitivity to environmental change. However, the effects of timber harvests on salamanders, though often researched, are still not well understood. To further this understanding, we used artificial cover objects to monitor the relative abundance of terrestrial salamanders for two seasons (fall and spring) pre-harvest and five seasons post-harvest in six forest management treatments, and for three seasons post-harvest across the edge gradients of six recent clearcuts. In total, we recorded 19,048 encounters representing nine species of salamanders. We observed declines in mean encounters of eastern red-backed salamanders (Plethodon cinereus) and northern slimy salamanders (P. glutinosus) from pre- to post-harvest in group selection cuts and in clearcuts. However, we found no evidence of salamander declines at shelterwoods and forested sites adjacent to harvests. Edge effects induced by recent clearcuts influenced salamanders for approximately 20 m into the forest, but edge influence varied by slope orientation. Temperature, soil moisture, and canopy cover were all correlated with salamander counts. Our results suggest silvicultural techniques that remove the forest canopy negatively affect salamander relative abundance on the local scale during the years immediately following harvest, and that the depth of edge influence of clearcuts on terrestrial salamanders is relatively shallow (<20 m). Small harvests (<4 ha) and techniques that leave the forest canopy intact may be compatible with maintaining terrestrial salamander populations across a forested landscape. Our results demonstrate the importance of examining species-specific responses and monitoring salamanders across multiple seasons and years

  3. Linking the evolution of habitat choice to ecosystem functioning: direct and indirect effects of pond-reproducing fire salamanders on aquatic-terrestrial subsidies.

    PubMed

    Reinhardt, Timm; Steinfartz, Sebastian; Paetzold, Achim; Weitere, Markus

    2013-09-01

    Shifts in life history traits and in the behaviour of species can potentially alter ecosystem functioning. The reproduction of the central European fire salamander (Salamandra salamandra), which usually deposits its larvae in first-order streams, in small pool and pond-like habitats, is an example of a recent local adaptation in this species. Here we aimed to quantify the direct and indirect effects of the predatory larvae on the aquatic food webs in the ponds and on the flux of matter between the ponds and adjacent terrestrial habitats. Our estimates are based on biomass data of the present pond fauna as well as on the analysis of stomach content data, growth rates and population dynamics of the salamander larvae in pond habitats. By their deposition of larvae in early spring, female fire salamanders import between 0.07 and 2.86 g dry mass m(-2) larval biomass into the ponds. Due to high mortality rates in the larval phase and the relatively small size at metamorphosis of the pond-adapted salamanders compared to stream-adapted ones, the biomass export of the metamorphosed salamanders clearly falls below the initial biomass import. Catastrophic events such as high water temperatures and low oxygen levels may even occasionally result in mass mortalities of salamander larvae and thus in a net 100 % import of the salamander biomass into the pond food webs. Indirect effects further accelerate this net import of matter into the aquatic habitat, e.g. the feeding of salamanders on aquatic insect larvae with the emergence of terrestrial adults-thus preventing export-and on terrestrial organisms that fall on the water surface (supporting import). This study demonstrates that the adaptation of salamanders to pond reproduction can alter food web linkages across ecosystem boundaries by enhancing the flux of materials and energy from terrestrial (i.e. forest) to the aquatic (i.e. pond) habitat. PMID:23358795

  4. Morbidity statistics

    PubMed Central

    Smith, Alwyn

    1969-01-01

    This paper is based on an analysis of questionnaires sent to the health ministries of Member States of WHO asking for information about the extent, nature, and scope of morbidity statistical information. It is clear that most countries collect some statistics of morbidity and many countries collect extensive data. However, few countries relate their collection to the needs of health administrators for information, and many countries collect statistics principally for publication in annual volumes which may appear anything up to 3 years after the year to which they refer. The desiderata of morbidity statistics may be summarized as reliability, representativeness, and relevance to current health problems. PMID:5306722

  5. Use of Fecal Occult Blood Tests as Epidemiologic Indicators of Morbidity Associated with Intestinal Schistosomiasis during Preventive Chemotherapy in Young Children

    PubMed Central

    Betson, Martha; Sousa-Figueiredo, José Carlos; Kabatereine, Narcis B.; Stothard, J. Russell

    2012-01-01

    There is a need for field-applicable markers to assess morbidity associated with intestinal schistosomiasis, especially in the context of preventive chemotherapy in young children. We investigated whether fecal occult blood (FOB) point-of-care tests could be used to assess intestinal pathology over a 12-month period in a cohort of 382 children (< 5 years of age). We found a strong association between egg-patent schistosomiasis and FOB at baseline (odds ratio [OR] = 3.1, P < 0.0001), 6 months (OR = 3.4, P < 0.0001), and 12 months (OR = 3.5, P < 0.0001), despite repeated chemotherapy. There were tendencies for prevalence of FOB to decrease in children who became egg negative and increase in those who became egg positive. Our results demonstrate overt disease in children less than five years of age. We therefore propose that FOB is useful for assessing dynamics of intestinal morbidity in young children at the community level and monitoring changes in morbidity after mass chemotherapy. PMID:22927499

  6. Maternal mortality and psychiatric morbidity in the perinatal period: challenges and opportunities for prevention in the Australian setting.

    PubMed

    Austin, Marie-Paule; Kildea, Susan; Sullivan, Elizabeth

    2007-04-01

    Maternal mortality associated with psychiatric illness in the perinatal period (pregnancy to the end of the first year postpartum) has until recently been under-reported in Australia due to limitations in the scope of the data collection and methods of detection. The recent United Kingdom report Why mothers die 2000-2002 identified psychiatric illness as the leading cause of maternal death in the UK. Findings from the last three reports on maternal deaths in Australia (covering the period 1994-2002) suggest that maternal psychiatric illness is one of the leading causes of maternal death, with the majority of suicides occurring by violent means. Such findings strengthen the case for routine perinatal psychosocial screening programs, with clear referral guidelines and assertive perinatal treatment of significant maternal psychiatric morbidity. Data linkage studies are needed to measure the full extent of maternal mortality associated with psychiatric illness in Australia. PMID:17407434

  7. Effectiveness of Tocolytic Agents on Prevention of Preterm Delivery, Neonatal Morbidity, and Mortality: Is There a Consensus? A Review of the Literature.

    PubMed

    Petousis, Stamatios; Margioula-Siarkou, Chrysoula; Kalogiannidis, Ioannis

    2016-04-01

    Preterm delivery presents the main cause of neonatal morbidity and mortality worldwide. The rate of preterm delivery is 12% to 13% in the United States, of which 29% concerns preterm deliveries before 34 weeks of gestation. Basic parameter of prevention strategy is implementation of tocolytic therapy in cases of threatened preterm labor. Several therapeutic approaches have been proposed, among which betamimetic agonists, calcium channel blockers, magnesium sulfate, oxytocin receptor blockers, nitrates, and prostaglandin inhibitors, whereas new alternatives such as usage of thiocolchicoside have also been reported. This article is one among few that aims to review the comparative effectiveness of various tocolytic agents regarding prevention of preterm delivery, impact on perinatal morbidity and mortality, neonatal health status, and maternal complications. Main conclusions of recent randomized control trials and meta-analyses are summarized to assess about which agents consensus already exists on their effectiveness, which agents should be further studied to achieve conclusions, as well as those that are rather unlikely to have significant tocolytic impact or any other benefit on neonatal outcome. PMID:27065070

  8. Preoperative prediction of potentially preventable morbidity after fast-track hip and knee arthroplasty: a detailed descriptive cohort study

    PubMed Central

    Petersen, Morten Aa; Kehlet, Henrik

    2016-01-01

    Objectives Construction of a simple preoperative risk score for patients in high risk of potentially preventable ‘medical’ complications. Secondary objectives were to construct simple preoperative risk scores for ‘severe medical’, ‘surgical’ and ‘total’ potentially preventable complications. Design Prospective observational study. Setting Elective primary unilateral total hip and knee arthroplasty with prospectively collected preoperative patient characteristics; similar standardised fast-track protocols; evaluation of complications through discharge and medical records; and complete 90 days follow-up through nationwide databases. Participants 8373 consecutive unselected total hip arthroplasty (THA) and knee arthroplasty from January 2010 to November 2012. Results There were 557 procedures (6.4%) followed by potentially preventable complications resulting in hospitalisation >4 days or readmission. Of 22 preoperative characteristics, 7 were associated with 379 (4.2%) potentially preventable ‘medical’ complications. Patients with ≥2 of the following, age ≥80 years, anticoagulant therapy, pulmonary disease, pharmacologically treated psychiatric disorder, anaemia and walking aids, composed 19.1% of the procedures; 55.7% constituted potentially preventable ‘medical’ complications that were mainly falls, mobilisation issues, pneumonias and cardiac arrhythmias. The number needed to be treated for a hypothetical intervention leading to 25% reduction in potentially preventable ‘medical’ complications was 34. THA, use of walking aids and cardiac disease were associated with 189 (2.2%) ‘surgical’ complications, but no clinically relevant preoperative prediction was possible. Conclusions Preoperative identification of patients at high risk of preventable ‘medical’, but not ‘surgical’, complications is statistically possible. However, clinical relevance is limited. Future risk indices should differ between ‘medical’ and

  9. Endothelin receptor antagonism prevents hypoxia-induced mortality and morbidity in a mouse model of sickle-cell disease

    PubMed Central

    Sabaa, Nathalie; de Franceschi, Lucia; Bonnin, Philippe; Castier, Yves; Malpeli, Giorgio; Debbabi, Haythem; Galaup, Ariane; Maier-Redelsperger, Micheline; Vandermeersch, Sophie; Scarpa, Aldo; Janin, Anne; Levy, Bernard; Girot, Robert; Beuzard, Yves; Leboeuf, Christophe; Henri, Annie; Germain, Stéphane; Dussaule, Jean-Claude; Tharaux, Pierre-Louis

    2008-01-01

    Patients with sickle-cell disease (SCD) suffer from tissue damage and life-threatening complications caused by vasoocclusive crisis (VOC). Endothelin receptors (ETRs) are mediators of one of the most potent vasoconstrictor pathways in mammals, but the relationship between vasoconstriction and VOC is not well understood. We report here that pharmacological inhibition of ETRs prevented hypoxia-induced acute VOC and organ damage in a mouse model of SCD. An in vivo ultrasonographic study of renal hemodynamics showed a substantial increase in endothelin-mediated vascular resistance during hypoxia/reoxygenation-induced VOC. This increase was reversed by administration of the dual ETR antagonist (ETRA) bosentan, which had pleiotropic beneficial effects in vivo. It prevented renal and pulmonary microvascular congestion, systemic inflammation, dense rbc formation, and infiltration of activated neutrophils into tissues with subsequent nitrative stress. Bosentan also prevented death of sickle-cell mice exposed to a severe hypoxic challenge. These findings in mice suggest that ETRA could be a potential new therapy for SCD, as it may prevent acute VOC and limit organ damage in sickle-cell patients. PMID:18382768

  10. Innovative techniques for sampling stream-inhabiting salamanders

    SciTech Connect

    T.M. Luhring; C.A. Young

    2006-01-01

    Although salamanders are excellent indicators of environmental health, the ability to catch them efficiently without substantially disrupting their habitat is not always practical or even possible with current techniques. Ripping open logs and raking leaf packs onto shore (Bruce 1972) are examples of such practices that are disruptive but widely used by herpetologists who have no other means of efficient collection. Drift fences with pitfall traps are effective in catching animals moving within or between habitats but are time consuming and require an initial financial investment and constant upkeep to maintain functionality and prevent animal fatalities (Gibbons and Semlitsch 1981). One current alternative to drift fences is the use of coverboards (Grant et al. 1992), which require less maintenance and sampling effort than drift fences. However, coverboards do not integrate captures over a long time period and often result in a lower number of captures per trap (Grant et al. 1992).

  11. Homing orientation in salamanders: A mechanism involving chemical cues

    NASA Technical Reports Server (NTRS)

    Madison, D. M.

    1972-01-01

    A detailed description is given of experiments made to determine the senses and chemical cues used by salamanders for homing orientation. Sensory impairment and cue manipulative techniques were used in the investigation. All experiments were carried out at night. Results show that sense impaired animals did not home as readily as those who were blind but retained their sensory mechanism. This fact suggests that the olfactory mechanism is necessary for homing in the salamander. It was determined that after the impaired salamander regenerated its sensory mechanism it too returned home. It was concluded that homing ability in salamanders is direction independent, distant dependent, and vision independent.

  12. Lethal effects of water quality on threatened California salamanders but not on co-occurring hybrid salamanders.

    PubMed

    Ryan, Maureen E; Johnson, Jarrett R; Fitzpatrick, Benjamin M; Lowenstine, Linda J; Picco, Angela M; Shaffer, H Bradley

    2013-02-01

    Biological invasions and habitat alteration are often detrimental to native species, but their interactions are difficult to predict. Interbreeding between native and introduced species generates novel genotypes and phenotypes, and human land use alters habitat structure and chemistry. Both invasions and habitat alteration create new biological challenges and opportunities. In the intensively farmed Salinas Valley, California (U.S.A.), threatened California tiger salamanders (Ambystoma californiense) have been replaced by hybrids between California tiger salamander and introduced barred tiger salamanders (Ambystoma tigrinum mavortium). We conducted an enclosure experiment to examine the effects habitat modification and relative frequency of hybrid and native California tiger salamanders have on recruitment of salamanders and their prey, Pacific chorus frogs (Pseudacris regilla). We tested whether recruitment differed among genetic classes of tiger salamanders (hybrid or native) and pond hydroperiod (seasonal or perennial). Roughly 6 weeks into the experiment, 70% (of 378 total) of salamander larvae died in 4 out of 6 ponds. Native salamanders survived (n = 12) in these ponds only if they had metamorphosed prior to the die-offs. During die-offs, all larvae of native salamanders died, whereas 56% of hybrid larvae died. We necropsied native and hybrid salamanders, tested water quality, and queried the California Department of Pesticide Regulation database to investigate possible causes of the die-offs. Salamander die-offs, changes in the abundance of other community members (invertebrates, algae, and cyanobacteria), shifts in salamander sex ratio, and patterns of pesticide application in adjacent fields suggest that pesticide use may have contributed to die-offs. That all survivors were hybrids suggests that environmental stress may promote rapid displacement of native genotypes. PMID:23140535

  13. Kinship affects morphogenesis in cannibalistic salamanders.

    PubMed

    Pfennig, D W; Collins, J P

    1993-04-29

    Inclusive fitness theory predicts that organisms can often increase their fitness by helping relatives. Indeed, many animals modify their behaviour towards kin in a fashion consistent with theory. Morphogenesis may also be sensitive to kinship environment, especially in species that facultatively produce distinct morphs that differ in their ability to harm relatives, such as those that produce alternative cannibalistic and non-cannibalistic phenotypes. We tested this hypothesis by examining whether consanguinity affected the probability that structurally distinctive cannibal morphs would develop in larval Arizona tiger salamanders (Ambystoma tigrinum nebulosum). We report here that when tiger salamander larvae are reared in mixed-brood groups they are significantly more likely to develop the cannibal morphology and at an earlier age than siblings reared in pure-sibship groups. In general, morphogenesis may be responsive to kinship in any species that facultatively develops structures that can be used against conspecifics as weaponry. PMID:8479520

  14. Type and Proximity of Green Spaces Are Important for Preventing Cardiovascular Morbidity and Diabetes-A Cross-Sectional Study for Quebec, Canada.

    PubMed

    Ngom, Roland; Gosselin, Pierre; Blais, Claudia; Rochette, Louis

    2016-01-01

    This study aimed at determining the role of proximity to specific types of green spaces (GSes) as well as their spatial location in the relationship with the most morbid cardiovascular diseases (CVD) and diabetes. We measured the accessibility to various types of GS and used a cross-sectional approach at census Dissemination Area (DA) levels in the Montreal and Quebec City metropolitan zones for the period 2006-2011. Poisson and negative binomial regression models were fitted to quantify the relationship between distances to specific types of GS and CVD morbidity as well as some risk factors (diabetes and hypertension) while controlling for several social and environmental confounders. GSes that have sports facilities showed a significant relationship to cerebrovascular diseases: the most distant population had an 11% higher prevalence rate ratio (PRR) compared to the nearest, as well as higher diabetes risk (PRR 9%) than the nearest. However, the overall model performance and the understanding of the role of GSes with sport facilities may be substantially achieved with lifestyle factors. Significantly higher prevalence of diabetes and cerebrovascular diseases as well as lower access to GSes equipped with sports facilities were found in suburban areas. GSes can advantageously be used to prevent some CVDs and their risk factors, but there may be a need to reconsider their types and location. PMID:27089356

  15. Type and Proximity of Green Spaces Are Important for Preventing Cardiovascular Morbidity and Diabetes—A Cross-Sectional Study for Quebec, Canada

    PubMed Central

    Ngom, Roland; Gosselin, Pierre; Blais, Claudia; Rochette, Louis

    2016-01-01

    This study aimed at determining the role of proximity to specific types of green spaces (GSes) as well as their spatial location in the relationship with the most morbid cardiovascular diseases (CVD) and diabetes. We measured the accessibility to various types of GS and used a cross-sectional approach at census Dissemination Area (DA) levels in the Montreal and Quebec City metropolitan zones for the period 2006–2011. Poisson and negative binomial regression models were fitted to quantify the relationship between distances to specific types of GS and CVD morbidity as well as some risk factors (diabetes and hypertension) while controlling for several social and environmental confounders. GSes that have sports facilities showed a significant relationship to cerebrovascular diseases: the most distant population had an 11% higher prevalence rate ratio (PRR) compared to the nearest, as well as higher diabetes risk (PRR 9%) than the nearest. However, the overall model performance and the understanding of the role of GSes with sport facilities may be substantially achieved with lifestyle factors. Significantly higher prevalence of diabetes and cerebrovascular diseases as well as lower access to GSes equipped with sports facilities were found in suburban areas. GSes can advantageously be used to prevent some CVDs and their risk factors, but there may be a need to reconsider their types and location. PMID:27089356

  16. Stream salamanders as indicators of stream quality in Maryland, USA

    USGS Publications Warehouse

    Southerland, M.T.; Jung, R.E.; Baxter, D.P.; Chellman, I.C.; Mercurio, G.; Volstad, J.H.

    2004-01-01

    Biological indicators are critical to the protection of small, headwater streams and the ecological values they provide. Maryland and other state monitoring programs have determined that fish indicators are ineffective in small streams, where stream salamanders may replace fish as top predators. Because of their life history, physiology, abundance, and ubiquity, stream salamanders are likely representative of biological integrity in these streams. The goal of this study was to determine whether stream salamanders are effective indicators of ecological conditions across biogeographic regions and gradients of human disturbance. During the summers of 2001 and 2002, we intensively surveyed for stream salamanders at 76 stream sites located west of the Maryland Coastal Plain, sites also monitored by the Maryland Biological Stream Survey (MBSS) and City of Gaithersburg. We found 1,584 stream salamanders, including all eight species known in Maryland, using two 15 ? 2 m transects and two 4 m2 quadrats that spanned both stream bank and channel. We performed removal sampling on transects to estimate salamander species detection probabilities, which ranged from 0.67-0.85. Stepwise regressions identified 15 of 52 non-salamander variables, representing water quality, physical habitat, land use, and biological conditions, which best predicted salamander metrics. Indicator development involved (1) identifying reference (non-degraded) and degraded sites (using percent forest, shading, riparian buffer width, aesthetic rating, and benthic macroinvertebrate and fish indices of biotic integrity); (2) testing 12 candidate salamander metrics (representing species richness and composition, abundance, species tolerance, and reproductive function) for their ability to distinguish reference from degraded sites; and (3) combining metrics into an index that effectively discriminated sites according to known stream conditions. Final indices for Highlands, Piedmont, and Non-Coastal Plain

  17. Comparing population size estimators for plethodontid salamanders

    USGS Publications Warehouse

    Bailey, L.L.; Simons, T.R.; Pollock, K.H.

    2004-01-01

    Despite concern over amphibian declines, few studies estimate absolute abundances because of logistic and economic constraints and previously poor estimator performance. Two estimation approaches recommended for amphibian studies are mark-recapture and depletion (or removal) sampling. We compared abundance estimation via various mark-recapture and depletion methods, using data from a three-year study of terrestrial salamanders in Great Smoky Mountains National Park. Our results indicate that short-term closed-population, robust design, and depletion methods estimate surface population of salamanders (i.e., those near the surface and available for capture during a given sampling occasion). In longer duration studies, temporary emigration violates assumptions of both open- and closed-population mark-recapture estimation models. However, if the temporary emigration is completely random, these models should yield unbiased estimates of the total population (superpopulation) of salamanders in the sampled area. We recommend using Pollock's robust design in mark-recapture studies because of its flexibility to incorporate variation in capture probabilities and to estimate temporary emigration probabilities.

  18. A Review of Medical and Substance Use Co-Morbidities in Central Asian Prisons: Implications for HIV Prevention and Treatment

    PubMed Central

    Polonsky, Maxim; Kerimi, Nina; Mamyrov, Mirlan; Dvoryak, Sergey; Altice, Frederick L.

    2013-01-01

    Background HIV incidence in Central Asia is rising rapidly. People who inject drugs (PWIDs) contribute greatest to the epidemic, with more than a quarter of all HIV cases being in the criminal justice system (CJS). This review assembled and aggregated recent data on drug-related health problems and respective healthcare services in the CJS of Central Asia and the Republic of Azerbaijan. Methods Online databases and published literature (peer-reviewed and grey) were reviewed. Additionally, prison officials in the 6 countries were invited to participate in a survey and prison administrators from Kazakhstan, Kyrgyzstan and Tajikistan completed it. Results The data on conditions and healthcare in Central Asian prisons are inconsistent and lack unbiased details. Reporting is primarily based on “official” disease registries, which markedly underestimate prevalence. Even these limited data, however, indicate that HIV prevalence and drug-related health problems are high, concentrated and, in some countries, rising rapidly. Only some of the range of HIV prevention interventions recommended by international organizations have been implemented in the region with two of the crucial interventions, needle and syringe exchange programs (NSP) and opioid substitution therapy (OST), only available in Kyrgyzstan prisons, with Tajikistan implementing a pilot NSP and contemplating introduction of prison-based OST. Conclusions Despite deficiencies in routine health reporting and insufficient HIV sentinel surveillance undertaken in prisons, the data available on the concentration of HIV within at-risk populations in prisons indicate a necessity to broaden the range and increase the scale the scale of HIV prevention and treatment services. PMID:23932844

  19. Bromeliad Selection by Two Salamander Species in a Harsh Environment

    PubMed Central

    Ruano-Fajardo, Gustavo; Rovito, Sean M.; Ladle, Richard J.

    2014-01-01

    Bromeliad phytotelmata are frequently used by several Neotropical amphibian taxa, possibly due to their high humidity, microclimatic stability, and role as a refuge from predators. Indeed, the ability of phytotelmata to buffer against adverse environmental conditions may be instrumental in allowing some amphibian species to survive during periods of environmental change or to colonize sub-optimal habitats. Association between bromeliad traits and salamanders has not been studied at a fine scale, despite the intimate association of many salamander species with bromeliads. Here, we identify microhabitat characteristics of epiphytic bromeliads used by two species of the Bolitoglossa morio group (B. morio and B. pacaya) in forest disturbed by volcanic activity in Guatemala. Specifically, we measured multiple variables for bromeliads (height and position in tree, phytotelma water temperature and pH, canopy cover, phytotelma size, leaf size, and tree diameter at breast height), as well as salamander size. We employed a DNA barcoding approach to identify salamanders. We found that B. morio and B. pacaya occurred in microsympatry in bromeliads and that phytotelmata size and temperature of bromeliad microhabitat were the most important factors associated with the presence of salamanders. Moreover, phytotelmata with higher pH contained larger salamanders, suggesting that larger salamanders or aggregated individuals might modify pH. These results show that bromeliad selection is nonrandom with respect to microhabitat characteristics, and provide insight into the relationship between salamanders and this unique arboreal environment. PMID:24892414

  20. Bromeliad selection by two salamander species in a harsh environment.

    PubMed

    Ruano-Fajardo, Gustavo; Rovito, Sean M; Ladle, Richard J

    2014-01-01

    Bromeliad phytotelmata are frequently used by several Neotropical amphibian taxa, possibly due to their high humidity, microclimatic stability, and role as a refuge from predators. Indeed, the ability of phytotelmata to buffer against adverse environmental conditions may be instrumental in allowing some amphibian species to survive during periods of environmental change or to colonize sub-optimal habitats. Association between bromeliad traits and salamanders has not been studied at a fine scale, despite the intimate association of many salamander species with bromeliads. Here, we identify microhabitat characteristics of epiphytic bromeliads used by two species of the Bolitoglossa morio group (B. morio and B. pacaya) in forest disturbed by volcanic activity in Guatemala. Specifically, we measured multiple variables for bromeliads (height and position in tree, phytotelma water temperature and pH, canopy cover, phytotelma size, leaf size, and tree diameter at breast height), as well as salamander size. We employed a DNA barcoding approach to identify salamanders. We found that B. morio and B. pacaya occurred in microsympatry in bromeliads and that phytotelmata size and temperature of bromeliad microhabitat were the most important factors associated with the presence of salamanders. Moreover, phytotelmata with higher pH contained larger salamanders, suggesting that larger salamanders or aggregated individuals might modify pH. These results show that bromeliad selection is nonrandom with respect to microhabitat characteristics, and provide insight into the relationship between salamanders and this unique arboreal environment. PMID:24892414

  1. Intermittent preventive treatment using artemisinin-based combination therapy reduces malaria morbidity among school-aged children in Mali

    PubMed Central

    Barger, Breanna; Maiga, Hamma; Traore, Oumar Bila; Tekete, Mamadou; Tembine, Intimbeye; Dara, Antoine; Traore, Zoumana Isaac; Gantt, Soren; Doumbo, Ogobara K.; Djimde, Abdoulaye A.

    2011-01-01

    Summary OBJECTIVE To assess the efficacy of intermittent preventive treatment (IPT) against malaria in school-aged children. METHODS This was an open randomized controlled trial of seasonal IPT among school children (IPTsc) aged 6–13 years in Kollé, Mali. The study began in September 2007 and completed follow-up in May 2008. Students were randomized to one of three study arms: Sulfadoxine–pyrimethamine plus artesunate (SP/AS), amodiaquine plus artesunate (AQ/AS) or vitamin C. All students received two full treatment doses, given 2 months apart during the season of high transmission from September to December. Groups were compared with respect to incidence of clinical malaria, asymptomatic parasitemia and haemoglobin concentration. RESULTS A total of 296 students were randomized, and retention in the study was 99.3%. Clinical malaria incidence in the SP/AS and AQ/AS arms was reduced by 66.6% and 46.5%, respectively, vs. vitamin C (P < 0.001). There were fewer clinic visits for any cause among the children receiving SP/AS or AQ/AS (P = 0.024). The prevalence of asymptomatic parasitemia was fivefold higher in the vitamin C arm than either SP/AS or AQ/AS at each post-treatment evaluation (P < 0.001). At the end of the transmission period, children treated with IPT had lower rates of anaemia (SP/AS, 17.7%; AQ/AS, 16.0%; vitamin C, 29.6%; P = 0.039). CONCLUSION IPT among school children reduced the rates of clinical malaria, all-cause acute clinic visits, asymptomatic parasitemia and anaemia among school-aged children. PMID:19497079

  2. Northwestern salamanders Ambystoma gracile in mountain lakes: record oviposition depths among salamanders

    USGS Publications Warehouse

    Hoffman, R., Jr.; Pearl, C.A.; Larson, G.L.; Samora, B.

    2012-01-01

    Oviposition timing, behaviors, and microhabitats of ambystomatid salamanders vary considerably (Egan and Paton 2004; Figiel and Semlitsch 1995; Howard and Wallace 1985; Mac-Cracken 2007). Regardless of species, however, females typically oviposit using sites conducive to embryo development and survival. For example, the results of an experiment by Figiel and Semlitsch (1995) on Ambystoma opacum (Marbled Salamander) oviposition indicated that females actively selected sites that were under grass clumps in wet versus dry treatments, and surmised that environmental conditions such as humidity, moisture, and temperature contributed to their results. Other factors associated with ambystomatid oviposition and embryo survival include water temperature (Anderson 1972; Brown 1976), dissolved oxygen concentration (Petranka et al. 1982; Sacerdote and King 2009), oviposition depth (Dougherty et al. 2005; Egan and Paton 2004), and oviposition attachment structures such as woody vegetation (McCracken 2007; Nussbaum et al. 1983). Resetarits (1996), in creating a model of oviposition site selection for anuran amphibians, hypothesized that oviparous organisms were also capable of modifying oviposition behavior and site selection to accommodate varying habitat conditions and to minimize potential negative effects of environmental stressors. Kats and Sih (1992), investigating the oviposition of Ambystoma barbouri (Streamside Salamander) in pools of a Kentucky stream, found that females preferred pools without predatory Lepomis cyanellus (Green Sunfish), and that the number of egg masses present in a pool historically containing fish increased significantly the year after fish had been extirpated from the pool. Palen et al. (2005) determined that Ambystoma gracile (Northwestern Salamander) and Ambystoma macrodactylum (Longtoed Salamander) eggs were deposited either at increased depth or in full shaded habitats, respectively, as water transperancy to UV-B radiation increased.

  3. Effects of red-backed salamanders on ecosystem functions.

    PubMed

    Hocking, Daniel J; Babbitt, Kimberly J

    2014-01-01

    Ecosystems provide a vast array of services for human societies, but understanding how various organisms contribute to the functions that maintain these services remains an important ecological challenge. Predators can affect ecosystem functions through a combination of top-down trophic cascades and bottom-up effects on nutrient dynamics. As the most abundant vertebrate predator in many eastern US forests, woodland salamanders (Plethodon spp.) likely affect ecosystems functions. We examined the effects of red-backed salamanders (Plethodon cinereus) on a variety of forest ecosystem functions using a combined approach of large-scale salamander removals (314-m(2) plots) and small-scale enclosures (2 m(2)) where we explicitly manipulated salamander density (0, 0.5, 1, 2, 4 m(-2)). In these experiments, we measured the rates of litter and wood decomposition, potential nitrogen mineralization and nitrification rates, acorn germination, and foliar insect damage on red oak seedlings. Across both experimental venues, we found no significant effect of red-backed salamanders on any of the ecosystem functions. We also found no effect of salamanders on intraguild predator abundance (carabid beetles, centipedes, spiders). Our study adds to the already conflicting evidence on effects of red-backed salamander and other amphibians on terrestrial ecosystem functions. It appears likely that the impact of terrestrial amphibians on ecosystem functions is context dependent. Future research would benefit from explicitly examining terrestrial amphibian effects on ecosystem functions under a variety of environmental conditions and in different forest types. PMID:24466269

  4. Effects of Red-Backed Salamanders on Ecosystem Functions

    PubMed Central

    Hocking, Daniel J.; Babbitt, Kimberly J.

    2014-01-01

    Ecosystems provide a vast array of services for human societies, but understanding how various organisms contribute to the functions that maintain these services remains an important ecological challenge. Predators can affect ecosystem functions through a combination of top-down trophic cascades and bottom-up effects on nutrient dynamics. As the most abundant vertebrate predator in many eastern US forests, woodland salamanders (Plethodon spp.) likely affect ecosystems functions. We examined the effects of red-backed salamanders (Plethodon cinereus) on a variety of forest ecosystem functions using a combined approach of large-scale salamander removals (314-m2 plots) and small-scale enclosures (2 m2) where we explicitly manipulated salamander density (0, 0.5, 1, 2, 4 m−2). In these experiments, we measured the rates of litter and wood decomposition, potential nitrogen mineralization and nitrification rates, acorn germination, and foliar insect damage on red oak seedlings. Across both experimental venues, we found no significant effect of red-backed salamanders on any of the ecosystem functions. We also found no effect of salamanders on intraguild predator abundance (carabid beetles, centipedes, spiders). Our study adds to the already conflicting evidence on effects of red-backed salamander and other amphibians on terrestrial ecosystem functions. It appears likely that the impact of terrestrial amphibians on ecosystem functions is context dependent. Future research would benefit from explicitly examining terrestrial amphibian effects on ecosystem functions under a variety of environmental conditions and in different forest types. PMID:24466269

  5. Paedomorphosis and simplification in the nervous system of salamanders.

    PubMed

    Roth, G; Nishikawa, K C; Naujoks-Manteuffel, C; Schmidt, A; Wake, D B

    1993-01-01

    Comparative neuroanatomists since Herrick [1914] have been aware of the paradox that the brain of amphibians, especially salamanders, is less complex than one would expect based on their phylogenetic position among the Tetrapoda. Many features of the brain are less differentiated in salamanders than in tetrapod outgroups, including chondrichthyans and bony fishes, and for some brain characters, the salamander brain is even more simple than that of the agnathans. Here, we perform a cladistic analysis on 23 characters of four sensory systems (visual, auditory, lateral line and olfactory) and the brain. Our taxa include myxinoids, lampreys, chondrichthyans, actinopterygians, Latimeria, Neoceratodus and the lepidosirenid lungfishes, amniotes, frogs, caecilians, salamanders and bolitoglossine salamanders. Of the 23 characters we examined, 19 are most parsimoniously interpreted as secondarily simplified in salamanders from a more complex ancestral state, two characters are equally parsimonious under both hypotheses, one character (well developed ipsilateral retinotectal projections) is more complex in bolitoglossine salamanders than in vertebrates generally, and only one character (migration of neurons in the medial pallium) is most parsimoniously interpreted as retention of the plesiomorphically simple condition. Secondary simplification of the salamander brain appears to result from paedomorphosis, or retention of juvenile or embryonic morphology into adulthood. Paedomorphosis is correlated with an increase in genome size, which in turn is positively correlated with cell size, but negatively correlated with cell proliferation and differentiation rates. Available data suggest that, although increasing genome size and paedomorphosis tend to compromise the function of the salamander brain, compensating mechanisms have evolved that may restore or even enhance brain function. PMID:8364715

  6. Locomotion and visually guided behavior in salamander: a neuromechanical study

    NASA Astrophysics Data System (ADS)

    Ijspeert, Auke J.; Arbib, Michael A.

    2000-10-01

    This article investigates the neural mechanisms underlying locomotion and visually-guided behavior in a lower vertebrate: the salamander. We develop connectionist models of the salamander's locomotor circuitry and visual system, and analyze their functioning by embedding them into a biomechanical simulation of the salamander's body. This work is therefore an experiment in computational neuroethology which aims at investigating how behavior results from the coupling of a central nervous system (CNS) and a body, and from the interactions of the CNS-body pair with the environment. We believe that understanding these mechanisms is not only relevant for neurobiology but also for potential applications in robotics.

  7. Could we also be regenerative superheroes, like salamanders?

    PubMed

    Dall'Agnese, Alessandra; Puri, Pier Lorenzo

    2016-09-01

    Development of methods to reawaken the semi-dormant regenerative potential that lies within adult human tissues would hold promise for the restoration of diseased or damaged organs and tissues. While most of the regeneration potential is suppressed in many vertebrates, including humans, during adult life, urodele amphibians (salamanders) retain their regenerative ability throughout adulthood. Studies in newts and axolotls, two salamander models, have provided significant knowledge about adult limb regeneration. In this review, we present a comparative analysis of salamander and mammalian regeneration and discuss how evolutionarily altered properties of the regenerative environment can be exploited to restore full regenerative potential in the human body. PMID:27338874

  8. Habitat requirements of New Mexico’s endangered salamanders

    USGS Publications Warehouse

    Ramotnik, Cindy A.; Scott, N.J.

    1988-01-01

    We measured habitat components for two state-listed endangered salamanders in New Mexico in 1986 and 1987. Both species are restricted to mesic environments within high-elevation, mixed coniferous forests. Steep slope and high elevation were the most useful variables for predicting the occurrence of Jemez Mountains salamanders and Sacramento Mountain salamanders, respectively. Although the discriminant models show some predictive value in detecting salamanders based on habitat variables, we believe that the best survey technique is ground-truth surveys in wet weather. A better fit of the discriminant models might be obtained by including variables not measured e.g., fire and logging history, and soil characteristics. We offer interim management guidelines as a result of our analysis.

  9. Salamander-like development in a seymouriamorph revealed by palaeohistology.

    PubMed

    Sanchez, Sophie; Klembara, Jozef; Castanet, Jacques; Steyer, J Sébastien

    2008-08-23

    The amniotes generally lay eggs on land and are thereby differentiated from lissamphibians (salamanders, frogs and caecilians) by their developmental pattern. Although a number of 330-300-Myr old fossils are regarded as early tetrapods placed close to amniotes on the basis of anatomical data, we still do not know whether their developmental pattern was more similar to those of lissamphibians or amniotes. Here we report palaeohistological and skeletochronological evidence supporting a salamander-like development in the seymouriamorph Discosauriscus. Its long-bone growth pattern, slow diaphyseal growth rate and delayed sexual maturity (at more than 10 years old) are more comparable with growth features of extant salamanders rather than extant amniotes, even though they are mostly hypothesized to be phylogenetically closer to living amniotes than salamanders. PMID:18460423

  10. Salamander chytrid fungus (Batrachochytrium salamandrivorans) in the United States—Developing research, monitoring, and management strategies

    USGS Publications Warehouse

    Grant, Evan H. Campbell; Muths, Erin L.; Katz, Rachel A.; Canessa, Stefano; Adams, Michael J.; Ballard, Jennifer R.; Berger, Lee; Briggs, Cheryl J.; Coleman, Jeremy; Gray, Matthew J.; Harris, M. Camille; Harris, Reid N.; Hossack, Blake R.; Huyvaert, Kathryn P.; Kolby, Jonathan E.; Lips, Karen R.; Lovich, Robert E.; McCallum, Hamish I.; Mendelson, Joseph R., III; Nanjappa, Priya; Olson, Deanna H.; Powers, Jenny G.; Richgels, Katherine L.D.; Russell, Robin E.; Schmidt, Benedikt R.; Spitzen-van der Sluijs, Annemarieka; Watry, Mary Kay; Woodhams, Douglas C.; White, C. LeAnn

    2016-01-01

    The recently (2013) identified pathogenic chytrid fungus, Batrachochytrium salamandrivorans (Bsal), poses a severe threat to the distribution and abundance of salamanders within the United States and Europe. Development of a response strategy for the potential, and likely, invasion of Bsal into the United States is crucial to protect global salamander biodiversity. A formal working group, led by Amphibian Research and Monitoring Initiative (ARMI) scientists from the U.S. Geological Survey (USGS) Patuxent Wildlife Research Center, Fort Collins Science Center, and Forest and Rangeland Ecosystem Science Center, was held at the USGS Powell Center for Analysis and Synthesis in Fort Collins, Colorado, United States from June 23 to June 25, 2015, to identify crucial Bsal research and monitoring needs that could inform conservation and management strategies for salamanders in the United States. Key findings of the workshop included the following: (1) the introduction of Bsal into the United States is highly probable, if not inevitable, thus requiring development of immediate short-term and long-term intervention strategies to prevent Bsal establishment and biodiversity decline; (2) management actions targeted towards pathogen containment may be ineffective in reducing the long-term spread of Bsal throughout the United States; and (3) early detection of Bsal through surveillance at key amphibian import locations, among high-risk wild populations, and through analysis of archived samples is necessary for developing management responses. Top research priorities during the preinvasion stage included the following: (1) deployment of qualified diagnostic methods for Bsal and establishment of standardized laboratory practices, (2) assessment of susceptibility for amphibian hosts (including anurans), and (3) development and evaluation of short- and long-term pathogen intervention and management strategies. Several outcomes were achieved during the workshop, including development

  11. Toxicological responses of red-backed salamanders (Plethodon cinereus) to soil exposures of copper.

    PubMed

    Bazar, Matthew A; Quinn, Michael J; Mozzachio, Kristie; Bleiler, John A; Archer, Christine R; Phillips, Carlton T; Johnson, Mark S

    2009-07-01

    Copper (Cu) has widespread military use in munitions and small arms, particularly as a protective jacket for lead projectiles. The distribution of Cu at many US military sites is substantial and sites of contamination include habitats in and around military storage facilities, manufacturing, load and packing plants, open burning/open detonation areas, and firing ranges. Some of these areas include habitat for amphibian species, which generally lack toxicity data for risk assessment purposes. In an effort to ascertain Cu concentrations in soil that are toxic to terrestrial amphibians, 100 red-backed salamanders (Plethodon cinereus) were randomly sorted by weight, assigned to either a control soil or one of four treatments amended with copper acetate in soil, and exposed for 28 days. Analytical mean soil concentrations were 18, 283, 803, 1333, and 2700 mg Cu/kg soil dry weight. Food consisted of uncontaminated flightless Drosophila melanogaster. Survival was reduced in salamanders exposed to 1333 and 2700 mg/kg by 55% and 100%, respectively. Mortality/morbidity occurred within the first 4 days of exposure. These data suggest that a Cu soil concentration of and exceeding 1333.3 +/- 120.2 mg/kg results in reduced survival, whereas hematology analyses suggest that a concentration of and exceeding 803.3 +/- 98.4 mg/kg might result in reduced total white blood cell count. No effects were observed at 283.3 +/- 36.7 mg/kg. PMID:18825446

  12. Migraine and Common Morbidities

    MedlinePlus

    ... headaches . Home > Migraine and Common Morbidities Print Email Migraine and Common Morbidities ACHE Newsletter Sign up for ... newsletter by entering your e-mail address below. Migraine and Common Morbidities For many patients, migraine is ...

  13. Variation in salamanders: an essay on genomes, development, and evolution.

    PubMed

    Brockes, Jeremy P

    2015-01-01

    Regeneration is studied in a few model species of salamanders, but the ten families of salamanders show considerable variation, and this has implications for our understanding of salamander biology. The most recent classification of the families identifies the cryptobranchoidea as the basal group which diverged in the early Jurassic. Variation in the sizes of genomes is particularly obvious, and reflects a major contribution from transposable elements which is already present in the basal group.Limb development has been a focus for evodevo studies, in part because of the variable property of pre-axial dominance which distinguishes salamanders from other tetrapods. This is thought to reflect the selective pressures that operate on a free-living aquatic larva, and might also be relevant for the evolution of limb regeneration. Recent fossil evidence suggests that both pre-axial dominance and limb regeneration were present 300 million years ago in larval temnospondyl amphibians that lived in mountain lakes. A satisfying account of regeneration in salamanders may need to address all these different aspects in the future. PMID:25740473

  14. Are Salamanders Useful Indicators of Hydrologic Permanence in Headwater Streams?

    NASA Astrophysics Data System (ADS)

    Johnson, B.; Fritz, K.

    2005-05-01

    Regulatory agencies need appropriate indicators of stream permanence to aid in jurisdictional determinations for headwater streams. We evaluated salamanders as permanence indicators because they are often abundant in fishless headwaters. Salamander and habitat data were collected in spring and summer 2003 from 59 sites located longitudinally along 17 forested streams in KY, IN, and OH. Larval Eurycea bislineata/cirrigera dominated all forests, and their abundances were highly correlated with drainage areas and channel dimensions. Appalachian streams were more diverse and had intermittent sites with more Desmognathus and Gyrinophilus spp. Of 22 sites where larvae were collected in spring, 9 sites subsequently dried in summer, suggesting salamanders either emigrated or died. We therefore only used taxa with multi-year larval stages as indicators of perennial water. Salamander larvae >1 yr old were collected from each locality in drainage areas <0.17 km2. However, these older larvae were often found in isolated pools that serve as refugia during dry periods. Findings suggest salamanders with multi-year larval periods can indicate perennial waters and that their use is more effective in Appalachia where abundance and diversity are high. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

  15. Origin and control of the dominant time constant of salamander cone photoreceptors

    PubMed Central

    Zang, Jingjing

    2012-01-01

    Recovery of the light response in vertebrate photoreceptors requires the shutoff of both active intermediates in the phototransduction cascade: the visual pigment and the transducin–phosphodiesterase complex. Whichever intermediate quenches more slowly will dominate photoresponse recovery. In suction pipette recordings from isolated salamander ultraviolet- and blue-sensitive cones, response recovery was delayed, and the dominant time constant slowed when internal [Ca2+] was prevented from changing after a bright flash by exposure to 0Ca2+/0Na+ solution. Taken together with a similar prior observation in salamander red-sensitive cones, these observations indicate that the dominance of response recovery by a Ca2+-sensitive process is a general feature of amphibian cone phototransduction. Moreover, changes in the external pH also influenced the dominant time constant of red-sensitive cones even when changes in internal [Ca2+] were prevented. Because the cone photopigment is, uniquely, exposed to the external solution, this may represent a direct effect of protons on the equilibrium between its inactive Meta I and active Meta II forms, consistent with the notion that the process dominating recovery of the bright flash response represents quenching of the active Meta II form of the cone photopigment. PMID:22802362

  16. Climate change and shrinking salamanders: alternative mechanisms for changes in plethodontid salamander body size.

    PubMed

    Connette, Grant M; Crawford, John A; Peterman, William E

    2015-08-01

    An increasing number of studies have demonstrated relationships between climate trends and body size change of organisms. In many cases, climate might be expected to influence body size by altering thermoregulation, energetics or food availability. However, observed body size change can result from a variety of ecological processes (e.g. growth, selection, population dynamics) or imperfect observation of biological systems. We used two extensive datasets to evaluate alternative mechanisms for recently reported changes in the observed body size of plethodontid salamanders. We found that mean adult body size of salamanders can be highly sensitive to survey conditions, particularly rainfall. This systematic bias in the detection of larger or smaller individuals could result in a signature of body size change in relation to reported climate trends when it is simply observation error. We also identify considerable variability in body size distributions among years and find that individual growth rates can be strongly influenced by weather. Finally, our study demonstrates that measures of mean adult body size can be highly variable among surveys and that large sample sizes may be required to make reliable inferences. Identifying the effects of climate change is a critical area of research in ecology and conservation. Researchers should be aware that observed changes in certain organisms can result from multiple ecological processes or systematic bias due to nonrandom sampling of populations. PMID:25641384

  17. Duration of immobility in salamanders, genus Plethodon (Caudata: Plethodontidae)

    USGS Publications Warehouse

    Dodd, C. Kenneth, Jr.

    1989-01-01

    Immobility is a potentially important antipredator behavior in salamanders, especially for those posessing noxious skin secretions. The duration of immobility in 15 species of terrestrial salamanders (Plethodon) varied among species. Most salamanders (78.8%) became immobile when initially contacted under field conditions, and remained immobile from 1-180 s. Immobility duration was inversely correlated with substrate temperature and covaried with air temperature, but snout-vent level (SVL) had no effect on duration. Only immobility times of Plethodon shenandoah were significantly different from any other species. Substrate temperature, air temperature, SVL, and species accounted for only a small percentage of the variance (r2=0.09). The degree of disturbance received during a predator-prey encounter is probably more important than the subtle effects of temperature and SVL in determining immobility duration.

  18. Small effective population size in the long-toed salamander.

    PubMed

    Funk, W C; Tallmon, D A; Allendorf, F W

    1999-10-01

    The effective population sizes (Ne) of six populations of the long-toed salamander (Ambystoma macrodactylum) from Montana and Idaho, USA were estimated from allozyme data from samples collected in 1978, 1996 and 1997 using the temporal allele frequency method. Five of the six estimates ranged from 23 to 207 (mean = 123 +/- 79); one estimate was indistinguishable from infinity. In order to infer the actual Ne of salamander populations, we compared the frequency distribution of our observed Ne estimates with distributions obtained from simulated populations of known Ne. Our observed Ne estimate distribution was consistent with distributions from simulated populations with Ne values of 10, 25, and 50, suggesting an actual Ne for each of the six salamander populations of less than 100. This Ne estimate agrees with most other Ne estimates for amphibians. We conclude by discussing the conservation implications of small Ne values in amphibians in the context of increasing isolation of populations due to habitat fragmentation. PMID:10583827

  19. Ecological implications of metabolic compensation at low temperatures in salamanders

    PubMed Central

    2016-01-01

    Global warming is influencing the biology of the world’s biota. Temperature increases are occurring at a faster pace than that experienced by organisms in their evolutionary histories, limiting the organisms’ response to new conditions. Mechanistic models that include physiological traits can help predict species’ responses to warming. Changes in metabolism at high temperatures are often examined; yet many species are behaviorally shielded from high temperatures. Salamanders generally favor cold temperatures and are one of few groups of metazoans to be most species-rich in temperate regions. I examined variation in body temperature, behavioral activity, and temperature dependence of resting heart rate, used as a proxy for standard metabolic rate, in fire salamanders (Salamandra salamandra). Over 26 years, I found that salamanders are behaviorally active at temperatures as low as 1 °C, and aestivate at temperatures above 16 °C. Infrared thermography indicates limited thermoregulation opportunities for these nocturnal amphibians. Temperature affects resting heart rate, causing metabolic depression above 11 °C, and metabolic compensation below 8 °C: heart rate at 3 °C is 224% the expected heart rate. Thus, salamanders operating at low temperatures during periods of peak behavioral activity are able to maintain a higher metabolic rate than the rate expected in absence of compensation. This compensatory mechanism has important ecological implications, because it increases estimated seasonal heart rates. Increased heart rate, and thus metabolism, will require higher caloric intake for field-active salamanders. Thus, it is important to consider a species performance breadth over the entire temperature range, and particularly low temperatures that are ecologically relevant for cold tolerant species such as salamanders. PMID:27257549

  20. Ecological implications of metabolic compensation at low temperatures in salamanders.

    PubMed

    Catenazzi, Alessandro

    2016-01-01

    Global warming is influencing the biology of the world's biota. Temperature increases are occurring at a faster pace than that experienced by organisms in their evolutionary histories, limiting the organisms' response to new conditions. Mechanistic models that include physiological traits can help predict species' responses to warming. Changes in metabolism at high temperatures are often examined; yet many species are behaviorally shielded from high temperatures. Salamanders generally favor cold temperatures and are one of few groups of metazoans to be most species-rich in temperate regions. I examined variation in body temperature, behavioral activity, and temperature dependence of resting heart rate, used as a proxy for standard metabolic rate, in fire salamanders (Salamandra salamandra). Over 26 years, I found that salamanders are behaviorally active at temperatures as low as 1 °C, and aestivate at temperatures above 16 °C. Infrared thermography indicates limited thermoregulation opportunities for these nocturnal amphibians. Temperature affects resting heart rate, causing metabolic depression above 11 °C, and metabolic compensation below 8 °C: heart rate at 3 °C is 224% the expected heart rate. Thus, salamanders operating at low temperatures during periods of peak behavioral activity are able to maintain a higher metabolic rate than the rate expected in absence of compensation. This compensatory mechanism has important ecological implications, because it increases estimated seasonal heart rates. Increased heart rate, and thus metabolism, will require higher caloric intake for field-active salamanders. Thus, it is important to consider a species performance breadth over the entire temperature range, and particularly low temperatures that are ecologically relevant for cold tolerant species such as salamanders. PMID:27257549

  1. Ontogenetic evidence for the Paleozoic ancestry of salamanders.

    PubMed

    Schoch, Rainer R; Carroll, Robert L

    2003-01-01

    The phylogenetic positions of frogs, salamanders, and caecilians have been difficult to establish. Data matrices based primarily on Paleozoic taxa support a monophyletic origin of all Lissamphibia but have resulted in widely divergent hypotheses of the nature of their common ancestor. Analysis that concentrates on the character states of the stem taxa of the extant orders, in contrast, suggests a polyphyletic origin from divergent Paleozoic clades. Comparison of patterns of larval development in Paleozoic and modern amphibians provides a means to test previous phylogenies based primarily on adult characteristics. This proves to be highly informative in the case of the origin of salamanders. Putative ancestors of salamanders are recognized from the Permo-Carboniferous boundary of Germany on the basis of ontogenetic changes observed in fossil remains of larval growth series. The entire developmental sequence from hatching to metamorphosis is revealed in an assemblage of over 600 specimens from a single locality, all belonging to the genus Apateon. Apateon forms the most speciose genus of the neotenic temnospondyl family Branchiosauridae. The sequence of ossification of individual bones and the changing configuration of the skull closely parallel those observed in the development of primitive living salamanders. These fossils provide a model of how derived features of the salamander skull may have evolved in the context of feeding specializations that appeared in early larval stages of members of the Branchiosauridae. Larvae of Apateon share many unique derived characters with salamanders of the families Hynobiidae, Salamandridae, and Ambystomatidae, which have not been recognized in any other group of Paleozoic amphibians. PMID:12752770

  2. Bleached pigment activates transduction in salamander cones

    PubMed Central

    1995-01-01

    We have used suction electrode recording together with rapid steps into 0.5 mM IBMX solution to investigate changes in guanylyl cyclase velocity produced by pigment bleaching in isolated cones of the salamander Ambystoma tigrinum. Both backgrounds and bleaches accelerate the time course of current increase during steps into IBMX. We interpret this as evidence that the velocity of the guanylyl cyclase is increased in background light or after bleaching. Our results indicate that cyclase velocity increases nearly linearly with increasing percent pigment bleached but nonlinearly (and may saturate) with increasing back-ground intensity. In cones (as previously demonstrated for rods), light-activated pigment and bleached pigment appear to have somewhat different effects on the transduction cascade. The effect of bleaching on cyclase rate is maintained for at least 15-20 min after the light is removed, much longer than is required after a bleach for circulating current and sensitivity to stabilize in an isolated cone. The effect on the cyclase rate can be completely reversed by treatment with liposomes containing 11-cis retinal. The effects of bleaching can also be partially reversed by beta-ionone, an analogue of the chromophore 11- cis-retinal which does not form a covalent attachment to opsin. Perfusion of a bleached cone with beta-ionone produces a rapid increase in circulating current and sensitivity, which rapidly reverses when the beta-ionone is removed. Perfusion with beta-ionone also causes a partial reversal of the bleach-induced acceleration of cyclase velocity. We conclude that bleaching produces an "equivalent background" excitation of the transduction cascade in cones, perhaps by a mechanism similar to that in rods. PMID:8786347

  3. Native Salamanders and Introduced Fish: Changing the Nature of Mountain Lakes and Ponds

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.

    2003-01-01

    During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of larval salamander populations. We conducted studies in two national parks to assess the abundances of salamander larvae in lakes with and without introduced fish. These studies suggest that the two salamander species were affected quite differently by the presence of introduced fish because of different life-history traits and different distributions of salamanders and fish within each park.

  4. Impact of valley fills on streamside salamanders in southern West Virginia

    USGS Publications Warehouse

    Wood, Petra Bohall; Williams, Jennifer M.

    2013-01-01

    Valley fills associated with mountaintop-removal mining bury stream headwaters and affect water quality and ecological function of reaches below fills. We quantified relative abundance of streamside salamanders in southern West Virginia during 2002 in three streams below valley fills (VFS) and in three reference streams (RS). We surveyed 36 10- × 2-m stream transects, once in summer and fall, paired by order and structure. Of 2,343 salamanders captured, 66.7% were from RS. Total salamanders (adults plus larvae) were more abundant in RS than VFS for first-order and second-order reaches. Adult salamanders had greater abundance in first-order reaches of RS than VFS. Larval salamanders were more abundant in second-order reaches of RS than VFS. No stream width or mesohabitat variables differed between VFS and RS. Only two cover variables differed. Silt cover, greater in VFS than RS first-order reaches, is a likely contributor to reduced abundance of salamanders in VFS. Second-order RS had more boulder cover than second-order VFS, which may have contributed to the higher total and larval salamander abundance in RS. Water chemistry assessments of our VFS and RS reported elevated levels of metal and ion concentrations in VFS, which can depress macroinvertebrate populations and likely affect salamander abundance. Valley fills appear to have significant negative effects on stream salamander abundance due to alterations in habitat structure, water quality and chemistry, and macroinvertebrate communities in streams below fills.

  5. A recommended early goal-directed management guideline for the prevention of hypothermia-related transfusion, morbidity, and mortality in severely injured trauma patients.

    PubMed

    Perlman, Ryan; Callum, Jeannie; Laflamme, Claude; Tien, Homer; Nascimento, Barto; Beckett, Andrew; Alam, Asim

    2016-01-01

    Hypothermia is present in up to two-thirds of patients with severe injury, although it is often disregarded during the initial resuscitation. Studies have revealed that hypothermia is associated with mortality in a large percentage of trauma cases when the patient's temperature is below 32 °C. Risk factors include the severity of injury, wet clothing, low transport unit temperature, use of anesthesia, and prolonged surgery. Fortunately, associated coagulation disorders have been shown to completely resolve with aggressive warming. Selected passive and active warming techniques can be applied in damage control resuscitation. While treatment guidelines exist for acidosis and bleeding, there is no evidence-based approach to managing hypothermia in trauma patients. We synthesized a goal-directed algorithm for warming the severely injured patient that can be directly incorporated into current Advanced Trauma Life Support guidelines. This involves the early use of warming blankets and removal of wet clothing in the prehospital phase followed by aggressive rewarming on arrival at the hospital if the patient's injuries require damage control therapy. Future research in hypothermia management should concentrate on applying this treatment algorithm and should evaluate its influence on patient outcomes. This treatment strategy may help to reduce blood loss and improve morbidity and mortality in this population of patients. PMID:27095272

  6. Salamander growth rates increase along an experimental stream phosphorus gradient.

    PubMed

    Bumpers, Phillip M; Maerz, John C; Rosemond, Amy D; Benstead, Jonathan P

    2015-11-01

    Nutrient-driven perturbations to the resource base of food webs are predicted to attenuate with trophic distance, so it is unclear whether higher-level consumers will generally respond to anthropogenic nutrient loading. Few studies have tested whether nutrient (specifically, nitrogen [N] and phosphorus [P]) enrichment of aquatic ecosystems propagates through multiple trophic levels to affect predators, or whether N vs. P is relatively more important in driving effects on food webs. We conducted two-year whole-stream N and P additions to five streams to generate gradients in N and P concentration and N:P ratio (target N:P = 2, 8, 16, 32, 128). Larval salamanders are vertebrate predators of primary and secondary macroinvertebrate consumers in many heterotrophic headwater streams in which the basal resources are detritus and associated microorganisms. We determined the effects of N and P on the growth rates of caged and free-roaming larval Desmognathus quadramaculatus and the average body size of larval Eurycea wilderae. Growth rates and average body size increased by up to 40% and 60%, respectively, with P concentration and were negatively related to N:P ratio. These findings were consistent across both species of salamanders using different methodologies (cage vs. free-roaming) and at different temporal scales (3 months vs. 2 yr). Nitrogen concentration was not significantly related to increased growth rate or body size of the salamander species tested. Our findings suggest that salamander growth responds to the relaxation of ecosystem-level P limitation and that moderate P enrichment can have relatively large effects on vertebrate predators in detritus-based food webs. PMID:27070018

  7. Age-related changes in the tiger salamander retina.

    PubMed

    Townes-Anderson, E; Colantonio, A; St Jules, R S

    1998-05-01

    Tiger salamanders have been used in visual science because of the large size of their cells and the ease of preparation and maintenance of in vitro retinal preparations. We have found that salamanders over 27 cm in length show a variety of visual abnormalities. Compared to smaller animals (15-23 cm), large animals exhibited a decrease in visual responses determined by tests of the optomotor reflex. Small animals responded correctly an average of 84.5% of the time in visual testing at three light levels compared to an average of 68.4% for the large animals with the poorest visual performance at the lowest level of illumination. In addition, large animals contained (i) histological degeneration of the outer retina, in particular, loss and disruption of outer segments and abnormalities of the retinal pigmented epithelium, (ii) loss of cells, including photoreceptors, by apoptosis as evaluated with the TUNEL technique, and (iii) an increase in the number of macrophages and lymphocytes within the retina as determined by morphological examination. These histological changes were present in all large animals and all quadrants of their retinas. In contrast, small animals showed virtually no retinal degeneration, no TUNEL-positive cells, and few immune-like cells in the retina. Since large animals are also older animals. the visual changes are age-related. Loss of visual function and histological degeneration in the outer retina also typify aged human eyes. Thus, we propose that large salamanders serve as an animal model for age-related retinal degeneration. In addition to providing a source of aging retina that is readily accessible to experimental manipulation, the salamander provides a pigmented retina with a mixed (2:1, rod:cone) population of photoreceptors, similar to the degeneration-prone parafoveal region of the human eye. PMID:9631666

  8. Apparent predation by Gray Jays, Perisoreus canadensis, on Long-toed Salamanders, Ambystoma macrodactylum, in the Oregon Cascade Range

    USGS Publications Warehouse

    Murray, M.P.; Pearl, C.A.; Bury, R.B.

    2005-01-01

    We report observations of Gray Jays (Perisoreus canadensis) appearing to consume larval Long-toed Salamanders (Ambystoma macrodactylum) in a drying subalpine pond in Oregon, USA. Corvids are known to prey upon a variety of anuran amphibians, but to our knowledge, this is the first report of predation by any corvid on aquatic salamanders. Long-toed Salamanders appear palatable to Gray Jays, and may provide a food resource to Gray Jays when salamander larvae are concentrated in drying temporary ponds.

  9. A Systematic Review of the Amount of Water per Person per Day Needed to Prevent Morbidity and Mortality in (Post-)Disaster Settings

    PubMed Central

    De Buck, Emmy; Borra, Vere; De Weerdt, Elfi; Vande Veegaete, Axel; Vandekerckhove, Philippe

    2015-01-01

    Background In order to improve the effectiveness and efficiency of humanitarian efforts, minimum standards for humanitarian assistance and key indicators, showing whether a standard has been attained, have been developed. However, many of these standards and indicators are based on a consensus on best practices and experiences in humanitarian response, because relevant evidence on the impact of humanitarian interventions is often lacking. Objectives One important example of a standard in humanitarian aid in a disaster setting is “water quantity.” The accompanying indicator states how many litres of water are needed per person per day in a disaster setting. It was our objective to determine the evidence base behind this indicator, in order to improve health outcomes such as morbidity (e.g., diarrhoea) and mortality. Methods A systematic review was performed searching The Cochrane Library, Medline and Embase. We included studies performed during disasters and in refugee camps that reported a specific water amount and health-related outcomes related to water shortages, including diarrhoea, cholera, and mortality. We used GRADE to determine the quality of evidence. Results Out of 3,630 articles, 111 references relevant to our question were selected. Based on our selection criteria, we finally retained 6 observational studies, including 1 study that was performed during the disaster and 5 studies in a post-disaster phase. From two studies there is conclusive evidence on the relationship between the amount of water received and diarrhoea or mortality rates in refugee camps. However, overall, these studies do not contain enough data with relevance to a specific amount of water, and the level of evidence is very low. Conclusions More primary research on water amounts in a disaster setting is necessary, so that the humanitarian sector can further professionalise its water-related standards, indicators and interventions. PMID:25961720

  10. Effects of hatching time for larval ambystomatid salamanders

    USGS Publications Warehouse

    Boone, M.D.; Scott, D.E.; Niewiarowski, P.H.

    2002-01-01

    In aquatic communities, the phenology of breeding may influence species interactions. In the early-breeding marbled salamander, Ambystoma opacum, timing of pond filling may determine whether interactions among larvae are competitive or predatory. The objectives of our studies were to determine how time of egg hatching affected size, larval period, and survival to metamorphosis in A. opacum, and if early-hatching in A. opacum influenced the competitive and predator-prey relationships with smaller larvae of the mole salamander, Ambystoma talpoideum. Salamander larvae were reared from hatching through metamorphosis in large, outdoor enclosures located in a natural temporary pond in Aiken County, South Carolina, in two experiments. In study 1, we reared early- and late-hatching A. opacum larvae separately from hatching through metamorphosis. In study 2, we examined how early- versus late-hatching A. opacum affected a syntopic species, A. talpoideum. In general, early-hatching A. opacum were larger and older at metamorphosis, had greater survival, and left the pond earlier than late-hatching larvae. Ambystoma talpoideum reared in the presence of early-hatching A. opacum had lower survival than in controls, suggesting that A. opacum may predate upon A. talpoideum when they gain a growth advantage over later-hatching larvae. Our studies demonstrate that time of pond filling and phenology of breeding may influence population dynamics and alter the nature of relationships that develop among species.

  11. Better than fish on land? Hearing across metamorphosis in salamanders.

    PubMed

    Christensen, Christian Bech; Lauridsen, Henrik; Christensen-Dalsgaard, Jakob; Pedersen, Michael; Madsen, Peter Teglberg

    2015-03-01

    Early tetrapods faced an auditory challenge from the impedance mismatch between air and tissue in the transition from aquatic to terrestrial lifestyles during the Early Carboniferous (350 Ma). Consequently, tetrapods may have been deaf to airborne sounds for up to 100 Myr until tympanic middle ears evolved during the Triassic. The middle ear morphology of recent urodeles is similar to that of early 'lepospondyl' microsaur tetrapods, and experimental studies on their hearing capabilities are therefore useful to understand the evolutionary and functional drivers behind the shift from aquatic to aerial hearing in early tetrapods. Here, we combine imaging techniques with neurophysiological measurements to resolve how the change from aquatic larvae to terrestrial adult affects the ear morphology and sensory capabilities of salamanders. We show that air-induced pressure detection enhances underwater hearing sensitivity of salamanders at frequencies above 120 Hz, and that both terrestrial adults and fully aquatic juvenile salamanders can detect airborne sound. Collectively, these findings suggest that early atympanic tetrapods may have been pre-equipped to aerial hearing and are able to hear airborne sound better than fish on land. When selected for, this rudimentary hearing could have led to the evolution of tympanic middle ears. PMID:25652830

  12. Mechanisms underlying vertebrate limb regeneration: lessons from the salamander.

    PubMed

    Brockes, Jeremy P; Gates, Phillip B

    2014-06-01

    Limb regeneration in adult salamanders proceeds by formation of a mound of progenitor cells called the limb blastema. It provides several pointers for regenerative medicine. These include the role of differentiated cells in the origin of the blastema, the role of regenerating axons of peripheral nerves and the importance of cell specification in conferring morphogenetic autonomy on the blastema. One aspect of regeneration that has received less attention is the ability to undergo multiple episodes without detectable change in the outcome, and with minimal effect of aging. We suggest that, although such pointers are valuable, it is important to understand why salamanders are the only adult tetrapod vertebrates able to regenerate their limbs. Although this remains a controversial issue, the existence of salamander-specific genes that play a significant role in the mechanism of regeneration provides evidence for the importance of local evolution, rather than a purely ancestral mechanism. The three-finger protein called Prod1 is discussed in the present article as an exemplar of this approach. PMID:24849229

  13. Evolutionary history of a complex adaptation: tetrodotoxin resistance in salamanders.

    PubMed

    Hanifin, Charles T; Gilly, William F

    2015-01-01

    Understanding the processes that generate novel adaptive phenotypes is central to evolutionary biology. We used comparative analyses to reveal the history of tetrodotoxin (TTX) resistance in TTX-bearing salamanders. Resistance to TTX is a critical component of the ability to use TTX defensively but the origin of the TTX-bearing phenotype is unclear. Skeletal muscle of TTX-bearing salamanders (modern newts, family: Salamandridae) is unaffected by TTX at doses far in excess of those that block action potentials in muscle and nerve of other vertebrates. Skeletal muscle of non-TTX-bearing salamandrids is also resistant to TTX but at lower levels. Skeletal muscle TTX resistance in the Salamandridae results from the expression of TTX-resistant variants of the voltage-gated sodium channel NaV 1.4 (SCN4a). We identified four substitutions in the coding region of salSCN4a that are likely responsible for the TTX resistance measured in TTX-bearing salamanders and variation at one of these sites likely explains variation in TTX resistance among other lineages. Our results suggest that exaptation has played a role in the evolution of the TTX-bearing phenotype and provide empirical evidence that complex physiological adaptations can arise through the accumulation of beneficial mutations in the coding region of conserved proteins. PMID:25346116

  14. Better than fish on land? Hearing across metamorphosis in salamanders

    PubMed Central

    Christensen, Christian Bech; Lauridsen, Henrik; Christensen-Dalsgaard, Jakob; Pedersen, Michael; Madsen, Peter Teglberg

    2015-01-01

    Early tetrapods faced an auditory challenge from the impedance mismatch between air and tissue in the transition from aquatic to terrestrial lifestyles during the Early Carboniferous (350 Ma). Consequently, tetrapods may have been deaf to airborne sounds for up to 100 Myr until tympanic middle ears evolved during the Triassic. The middle ear morphology of recent urodeles is similar to that of early ‘lepospondyl’ microsaur tetrapods, and experimental studies on their hearing capabilities are therefore useful to understand the evolutionary and functional drivers behind the shift from aquatic to aerial hearing in early tetrapods. Here, we combine imaging techniques with neurophysiological measurements to resolve how the change from aquatic larvae to terrestrial adult affects the ear morphology and sensory capabilities of salamanders. We show that air-induced pressure detection enhances underwater hearing sensitivity of salamanders at frequencies above 120 Hz, and that both terrestrial adults and fully aquatic juvenile salamanders can detect airborne sound. Collectively, these findings suggest that early atympanic tetrapods may have been pre-equipped to aerial hearing and are able to hear airborne sound better than fish on land. When selected for, this rudimentary hearing could have led to the evolution of tympanic middle ears. PMID:25652830

  15. Extreme morphological and ecological homoplasy in tropical salamanders

    PubMed Central

    Parra-Olea, Gabriela; Wake, David B.

    2001-01-01

    Fossorial salamanders typically have elongate and attenuated heads and bodies, diminutive limbs, hands and feet, and extremely elongate tails. Batrachoseps from California, Lineatriton from eastern México, and Oedipina from southern México to Ecuador, all members of the family Plethodontidae, tribe Bolitoglossini, resemble one another in external morphology, which has evolved independently. Whereas Oedipina and Batrachoseps are elongate because there are more trunk vertebrae, a widespread homoplasy (parallelism) in salamanders, the genus Lineatriton is unique in having evolved convergently by an alternate “giraffe-neck” developmental program. Lineatriton has the same number of trunk vertebrae as related, nonelongated taxa, but individual trunk vertebrae are elongated. A robust phylogenetic hypothesis, based on sequences of three mtDNA genes, finds Lineatriton to be deeply nested within a clade characterized by generalized ecology and morphology. Lineatriton lineolus, the only currently recognized taxon in the genus, shows unanticipated genetic diversity. Surprisingly, geographically separated populations of L. lineolus are not monophyletic, but are sister taxa of different species of the morphologically generalized genus Pseudoeurycea. Lineatriton, long thought to be a unique monospecific lineage, is polyphyletic. Accordingly, the specialized morphology of Lineatriton displays homoplasy at two hierarchical levels: (i) with respect to other elongate lineages in the family (convergence), and (ii) within what is currently recognized as a single taxon (parallelism). These evolutionary events are of adaptive significance because to invade the lowland tropics salamanders must be either arboreal or fossorial; the repeated evolution of elongation and attenuation has led to multiple lowland invasions. PMID:11427707

  16. Cannibalistic-morph Tiger Salamanders in unexpected ecological contexts

    USGS Publications Warehouse

    McLean, Kyle I.; Stockwell, Craig A.; Mushet, David M.

    2016-01-01

    Barred tiger salamanders [Ambystoma mavortium (Baird, 1850)] exhibit two trophic morphologies; a typical and a cannibalistic morph. Cannibalistic morphs, distinguished by enlarged vomerine teeth, wide heads, slender bodies, and cannibalistic tendencies, are often found where conspecifics occur at high density. During 2012 and 2013, 162 North Dakota wetlands and lakes were sampled for salamanders. Fifty-one contained A. mavortium populations; four of these contained cannibalistic morph individuals. Two populations with cannibalistic morphs occurred at sites with high abundances of conspecifics. However, the other two populations occurred at sites with unexpectedly low conspecific but high fathead minnow [Pimephales promelas (Rafinesque, 1820)] abundances. Further, no typical morphs were observed in either of these later two populations, contrasting with earlier research suggesting cannibalistic morphs only occur at low frequencies in salamander populations. Another anomaly of all four populations was the occurrence of cannibalistic morphs in permanent water sites, suggesting their presence was due to factors other than faster growth allowing them to occupy ephemeral habitats. Therefore, our findings suggest environmental factors inducing the cannibalistic morphism may be more complex than previously thought.

  17. Detection of an enigmatic plethodontid Salamander using Environmental DNA

    USGS Publications Warehouse

    Pierson, Todd W.; Mckee, Anna; Spear, Stephen F.; Maerz, John C.; Camp, Carlos D.; Glenn, Travis C.

    2016-01-01

    The isolation and identification of environmental DNA (eDNA) offers a non-invasive and efficient method for the detection of rare and secretive aquatic wildlife, and it is being widely integrated into inventory and monitoring efforts. The Patch-Nosed Salamander (Urspelerpes brucei) is a tiny, recently discovered species of plethodontid salamander known only from headwater streams in a small region of Georgia and South Carolina. Here, we present results of a quantitative PCR-based eDNA assay capable of detecting Urspelerpes in more than 75% of 33 samples from five confirmed streams. We deployed the method at 31 additional streams and located three previously undocumented populations of Urspelerpes. We compare the results of our eDNA assay with our attempt to use aquatic leaf litterbags for the rapid detection of Urspelerpes and demonstrate the relative efficacy of the eDNA assay. We suggest that eDNA offers great potential for use in detecting other aquatic and semi-aquatic plethodontid salamanders.

  18. Origin and diversification of a salamander sex pheromone system.

    PubMed

    Janssenswillen, Sunita; Vandebergh, Wim; Treer, Dag; Willaert, Bert; Maex, Margo; Van Bocxlaer, Ines; Bossuyt, Franky

    2015-02-01

    Sex pheromones form an important facet of reproductive strategies in many organisms throughout the Animal Kingdom. One of the oldest known sex pheromones in vertebrates are proteins of the Sodefrin Precursor-like Factor (SPF) system, which already had a courtship function in early salamanders. The subsequent evolution of salamanders is characterized by a diversification in courtship and reproduction, but little is known on how the SPF pheromone system diversified in relation to changing courtship strategies. Here, we combined transcriptomic, genomic, and phylogenetic analyses to investigate the evolution of the SPF pheromone system in nine salamandrid species with distinct courtship displays. First, we show that SPF originated from vertebrate three-finger proteins and diversified through multiple gene duplications in salamanders, while remaining a single copy in frogs. Next, we demonstrate that tail-fanning newts have retained a high phylogenetic diversity of SPFs, whereas loss of tail-fanning has been associated with a reduced importance or loss of SPF expression in the cloacal region. Finally, we show that the attractant decapeptide sodefrin is cleaved from larger SPF precursors that originated by a 62 bp insertion and consequent frameshift in an ancestral Cynops lineage. This led to the birth of a new decapeptide that rapidly evolved a pheromone function independently from uncleaved proteins. PMID:25415963

  19. Hellbender Genome Sequences Shed Light on Genomic Expansion at the Base of Crown Salamanders

    PubMed Central

    Sun, Cheng; Mueller, Rachel Lockridge

    2014-01-01

    Among animals, genome sizes range from 20 Mb to 130 Gb, with 380-fold variation across vertebrates. Most of the largest vertebrate genomes are found in salamanders, an amphibian clade of 660 species. Thus, salamanders are an important system for studying causes and consequences of genomic gigantism. Previously, we showed that plethodontid salamander genomes accumulate higher levels of long terminal repeat (LTR) retrotransposons than do other vertebrates, although the evolutionary origins of such sequences remained unexplored. We also showed that some salamanders in the family Plethodontidae have relatively slow rates of DNA loss through small insertions and deletions. Here, we present new data from Cryptobranchus alleganiensis, the hellbender. Cryptobranchus and Plethodontidae span the basal phylogenetic split within salamanders; thus, analyses incorporating these taxa can shed light on the genome of the ancestral crown salamander lineage, which underwent expansion. We show that high levels of LTR retrotransposons likely characterize all crown salamanders, suggesting that disproportionate expansion of this transposable element (TE) class contributed to genomic expansion. Phylogenetic and age distribution analyses of salamander LTR retrotransposons indicate that salamanders’ high TE levels reflect persistence and diversification of ancestral TEs rather than horizontal transfer events. Finally, we show that relatively slow DNA loss rates through small indels likely characterize all crown salamanders, suggesting that a decreased DNA loss rate contributed to genomic expansion at the clade’s base. Our identification of shared genomic features across phylogenetically distant salamanders is a first step toward identifying the evolutionary processes underlying accumulation and persistence of high levels of repetitive sequence in salamander genomes. PMID:25115007

  20. Early Miocene origin and cryptic diversification of South American salamanders

    PubMed Central

    2013-01-01

    Background The currently recognized species richness of South American salamanders is surprisingly low compared to North and Central America. In part, this low richness may be due to the salamanders being a recent arrival to South America. Additionally, the number of South American salamander species may be underestimated because of cryptic diversity. The aims of our present study were to infer evolutionary relationships, lineage diversity, and timing of divergence of the South American Bolitoglossa using mitochondrial and nuclear sequence data from specimens primarily from localities in the Andes and upper Amazon Basin. We also estimated time of colonization of South America to test whether it is consistent with arrival via the Panamanian Isthmus, or land bridge connection, at its traditionally assumed age of 3 million years. Results Divergence time estimates suggest that Bolitoglossa arrived in South America from Central America by at least the Early Miocene, ca. 23.6 MYA (95% HPD 15.9-30.3 MYA), and subsequently diversified. South American salamanders of the genus Bolitoglossa show strong phylogeographic structure at fine geographic scales and deep divergences at the mitochondrial gene cytochrome b (Cytb) and high diversity at the nuclear recombination activating gene-1 (Rag1). Species often contain multiple genetically divergent lineages that are occasionally geographically overlapping. Single specimens from two southeastern localities in Ecuador are sister to the equatoriana-peruviana clade and genetically distinct from all other species investigated to date. Another single exemplar from the Andes of northwestern Ecuador is highly divergent from all other specimens and is sister to all newly studied samples. Nevertheless, all sampled species of South American Bolitoglossa are members of a single clade that is one of several constituting the subgenus Eladinea, one of seven subgenera in this large genus. Conclusions The ancestors of South American salamanders

  1. Habitat relationships of eastern red-backed salamanders (Plethodon cinereus) in Appalachian grazing systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Altered microclimates and vegetation structure after timber harvest can result in longterm population declines of some Appalachian salamanders. If changes in forest structure following harvest alter woodland salamander habitat quality, conversion of forests to pastures or meadows is believed to resu...

  2. Telocytes in ileum of the Chinese giant salamander: ultrastructural evidence.

    PubMed

    Zhang, Hui; Zhong, Shengwei; Ge, Tingting; Peng, Shasha; Yu, Pengcheng; Zhou, Zuohong; Guo, Xiaoquan

    2016-03-01

    Telocytes (TCs) and their telopodes (Tps) have been found in various organs of many mammals, including in lower animals. However, knowledge of TCs in lower animals is still very limited. This study identified TCs and their Tps in the ileum of the Chinese giant salamander, Andrias davidianus (Amphibia: Caudata), by transmission electron microscopy. The TCs/Tps were found near epithelial cells, glandular cells and unmyelinated nerve fibres. Moreover, exosomes were also found to be present in between TCs/Tps and these cells. PMID:26805522

  3. Earthworms, as ecosystem engineers, influence multiple aspects of a salamander's ecology.

    PubMed

    Ransom, Tami S

    2011-03-01

    Ecosystem engineers create habitat that can be used by other species in multiple ways, such as refugees from predators, places to breed, or areas with increased prey resources. I conducted a series of enclosure experiments to: (1) determine if salamanders use earthworm burrows, and (2) examine the potential influence of earthworm burrow use and indirect effects on salamander intra- and interspecific competition, predator avoidance, and seasonal performance. I found that one species of woodland salamander, Plethodon cinereus, used earthworm burrows 50% of the time when burrows were present. Neither adults nor juveniles of the congeneric P. glutinosus used earthworm burrows. Intraspecific, but not interspecific, competition by P. cinereus affected salamander behavior when earthworms were absent, with P. cinereus found under cover objects >70% of the time when alone or with a P. glutinosus, but only 40% of the time when with another P. cinereus. When earthworms were present, the behavior of P. cinereus was similar across salamander treatments. Earthworms decreased the amount of leaf litter and microinvertebrates, although this did not affect salamander mass. In subsequent experiments using only P. cinereus, the refuge provided by earthworm burrows increased the survival of P. cinereus over the winter and allowed P. cinereus to avoid being consumed by the common garter snake (Thamnophis sirtalis). Because earthworm burrows provide a refuge for P. cinereus during intraspecific encounters, in the presence of a predator and over the winter, they may serve as an important belowground-aboveground linkage in eastern forests where salamanders are common. PMID:20848134

  4. The Effectiveness of Universal School-Based Programs for the Prevention of Violent and Aggressive Behavior: A Report on Recommendations of the Task Force on Community Preventive Services. Morbidity and Mortality Weekly Report. Volume 56, Number RR-7

    ERIC Educational Resources Information Center

    Hahn, Robert; Fuqua-Whitley, Dawna; Wethington, Holly; Lowy, Jessica; Liberman, Akiva; Crosby, Alex; Fullilove, Mindy; Johnson, Robert; Moscicki, Eve; Price, LeShawndra; Snyder, Susan R.; Tuma, Farris; Cory, Stella; Stone, Glenda; Mukhopadhaya, Kaushik; Chattopadhyay, Sajal; Dahlberg, Linda

    2007-01-01

    Universal school-based programs to reduce or prevent violent behavior are delivered to all children in classrooms in a grade or in a school. Similarly, programs targeted to schools in high-risk areas (defined by low socioeconomic status or high crime rates) are delivered to all children in a grade or school in those high-risk areas. During…

  5. Science Review for the Scott Bar Salamander (Plethodon asupak) and the Siskiyou Mountains Salamander (P. stormi): Biology, Taxonomy, Habitat, and Detection Probabilities/Occupancy

    USGS Publications Warehouse

    DeGross, Douglas J.; Bury, R. Bruce

    2007-01-01

    The Plethodon elongatus Complex in the Klamath-Siskiyou Ecoregion of southern Oregon and northern California includes three species: the Del Norte salamander, Plethodon elongatus; the Siskiyou Mountains salamander, P. stormi; and the Scott Bar salamander, P. asupak. This review aims to summarize the current literature and information available on select topics for P. stormi and P. asupak. These are both terrestrial salamanders belonging to the Family Plethodontidae, which contains more species and has a wider geographic distribution than any other family of salamanders (Wake 1966, 2006; Pough 1989). The genera of this family have greatly diversified ecologically across North America, Central America, northern South America, Sardinia, southeastern France and northwestern Italy, and have recently been discovered on the Korean peninsula (Min et al. 2005). The genus Plethodon is found exclusively in North America and is split into three distinct clades, based upon morphology and phylogenetics (Highton and Larson 1979): eastern small Plethodon, eastern large Plethodon, and the western Plethodon. The western Plethodon are the greatest representation of Plethodontidae in the Pacific Northwest, with 8 species. The two species with the most restricted ranges of these regional congeners are the Siskiyou Mountains and Scott Bar salamanders. These salamanders occupy the interior of the Klamath-Siskiyou Ecoregion which straddles the California and Oregon state lines, between Siskiyou County (CA) and Jackson and Josephine Counties (OR). The relatively recent discovery of P. asupak (Mead et al. 2005) and the limited range of both species have created an environment of uncertain conservation status for these species. This review will focus on four central topics of concern for land and resource managers: Biology; Taxonomy; Habitat; and Detection Probabilities/Occupancy.

  6. Extreme negative temperatures and body mass loss in the Siberian salamander (Salamandrella keyserlingii, amphibia, hynobiidae).

    PubMed

    Berman, D I; Meshcheryakova, E N; Bulakhova, N A

    2016-05-01

    Frozen Siberian salamander safely tolerates long (45 days) stay at-35°C. Short-term (3 days) cooling down to-50°C was tolerable for 40% of adult individuals; down to-55°C, for 80% of the underyearlings. Generally, the salamanders lose about 28% of the body mass during the pre-hibernating period (before winter, at temperatures as low as 0°C) and during the process of freezing (as low as-5°C). The body weight remained constant upon further cooling (to-35°C). The frozen salamanders have no physiological mechanisms protecting from sublimation. PMID:27411827

  7. A field test of the effect of acidic rain on ion balance in a woodland salamander

    SciTech Connect

    Frisbie, M.P.; Wyman, R.L. )

    1994-06-01

    Earlier laboratory studies demonstrated that red-backed salamanders, Plethodon cinereus, are susceptible to osmotic disruption by low pH substrates. In natural systems, however, acidic input from precipitation may be mediated by soils before it impacts salamanders. We tested the effect of acidic rain on sodium balance in salamanders by confining individuals in enclosure in two forest types (hemlock, beech) for 34 d. Enclosures received artificial rain of either pH 3 or 5 every 3-4 d. Soils inside enclosures in the hemlock forest were more acidic than those in the beech forest at the outset. At termination, [H[sup +

  8. Elevated plasma corticosterone increases metabolic rate in a terrestrial salamander.

    PubMed

    Wack, Corina L; DuRant, Sarah E; Hopkins, William A; Lovern, Matthew B; Feldhoff, Richard C; Woodley, Sarah K

    2012-02-01

    Plasma glucocorticoid hormones (GCs) increase intermediary metabolism, which may be reflected in whole-animal metabolic rate. Studies in fish, birds, and reptiles have shown that GCs may alter whole-animal energy expenditure, but results are conflicting and often involve GC levels that are not physiologically relevant. A previous study in red-legged salamanders found that male courtship pheromone increased plasma corticosterone (CORT; the primary GC in amphibians) concentrations in males, which could elevate metabolic processes to sustain courtship behaviors. To understand the possible metabolic effect of elevated plasma CORT, we measured the effects of male courtship pheromone and exogenous application of CORT on oxygen consumption in male red-legged salamanders (Plethodon shermani). Exogenous application of CORT elevated plasma CORT to physiologically relevant levels. Compared to treatment with male courtship pheromone and vehicle, treatment with CORT increased oxygen consumption rates for several hours after treatment, resulting in 12% more oxygen consumed (equivalent to 0.33 J) during our first 2h sampling period. Contrary to our previous work, treatment with pheromone did not increase plasma CORT, perhaps because subjects used in this study were not in breeding condition. Pheromone application did not affect respiration rates. Our study is one of the few to evaluate the influence of physiologically relevant elevations in CORT on whole-animal metabolism in vertebrates, and the first to show that elevated plasma CORT increases metabolism in an amphibian. PMID:22047668

  9. Strong selection barriers explain microgeographic adaptation in wild salamander populations.

    PubMed

    Richardson, Jonathan L; Urban, Mark C

    2013-06-01

    Microgeographic adaptation occurs when populations evolve divergent fitness advantages across the spatial scales at which focal organisms regularly disperse. Although an increasing number of studies find evidence for microgeographic adaptation, the underlying causes often remain unknown. Adaptive divergence requires some combination of limited gene flow and strong divergent natural selection among populations. In this study, we estimated the relative influence of selection, gene flow, and the spatial arrangement of populations in shaping patterns of adaptive divergence in natural populations of the spotted salamander (Ambystoma maculatum). Within the study region, A. maculatum co-occur with the predatory marbled salamander (Ambystoma opacum) in some ponds, and past studies have established a link between predation risk and adaptive trait variation in A. maculatum. Using 14 microsatellite loci, we found a significant pattern of genetic divergence among A. maculatum populations corresponding to levels of A. opacum predation risk. Additionally, A. maculatum foraging rate was strongly associated with predation risk, genetic divergence, and the spatial relationship of ponds on the landscape. Our results indicate the sorting of adaptive genotypes by selection regime and strongly suggest that substantial selective barriers operate against gene flow. This outcome suggests that microgeographic adaptation in A. maculatum is possible because strong antagonistic selection quickly eliminates maladapted phenotypes despite ongoing and substantial immigration. Increasing evidence for microgeographic adaptation suggests a strong role for selective barriers in counteracting the homogenizing influence of gene flow. PMID:23730765

  10. Spermatogenic cycle of a plethodontid salamander, Eurycea longicauda (Amphibia, Urodela)

    PubMed Central

    Siegel, Dustin S; Alvino, Sam; Trauth, Stanley E; Sever, David M; Gribbins, Kevin M

    2014-01-01

    Previous investigators have described the spermatogenic cycles of numerous species of plethodontid salamanders. Most studies describe a fairly stereotypical cycle with meiotic divisions of spermatogenesis commencing in the spring/summer. However, many studies lack details obtainable from histological examination and/or testicular squashes and, instead, provide only mensural data from the testes. Studies that lacked microscopic evaluation often revealed spermatogenic cycles that varied greatly from that of the stereotypical cycle with meiotic divisions commencing in the fall/winter. Those studies hamper comparisons between the spermatogenic cycles of different species and their environments, as they do not provide a correlation between testicular size and any aspect of the spermatogenic cycle. In the following manuscript, we elucidate the spermatogenic cycle of Eurycea longicauda longicauda in an effort to outline an appropriate protocol for analyzing spermatogenesis in salamanders that will facilitate future comparative studies. Like many Nearctic plethodontids, E. l. longicauda exhibits a meiotic wave that travels through the testes during the summer; this process is followed by spermiogenesis, spermiation, and recrudescence in the fall, winter, and spring. PMID:26413402

  11. Evidence for Sex Chromosome Turnover in Proteid Salamanders.

    PubMed

    Sessions, Stanley K; Bizjak Mali, Lilijana; Green, David M; Trifonov, Vladimir; Ferguson-Smith, Malcolm

    2016-01-01

    A major goal of genomic and reproductive biology is to understand the evolution of sex determination and sex chromosomes. Species of the 2 genera of the Salamander family Proteidae - Necturus of eastern North America, and Proteus of Southern Europe - have similar-looking karyotypes with the same chromosome number (2n = 38), which differentiates them from all other salamanders. However, Necturus possesses strongly heteromorphic X and Y sex chromosomes that Proteus lacks. Since the heteromorphic sex chromosomes of Necturus were detectable only with C-banding, we hypothesized that we could use C-banding to find sex chromosomes in Proteus. We examined mitotic material from colchicine-treated intestinal epithelium, and meiotic material from testes in specimens of Proteus, representing 3 genetically distinct populations in Slovenia. We compared these results with those from Necturus. We performed FISH to visualize telomeric sequences in meiotic bivalents. Our results provide evidence that Proteus represents an example of sex chromosome turnover in which a Necturus-like Y-chromosome has become permanently translocated to another chromosome converting heteromorphic sex chromosomes to homomorphic sex chromosomes. These results may be key to understanding some unusual aspects of demographics and reproductive biology of Proteus, and are discussed in the context of models of the evolution of sex chromosomes in amphibians. PMID:27351721

  12. Phylogeny, evolution, and biogeography of Asiatic Salamanders (Hynobiidae)

    PubMed Central

    Zhang, Peng; Chen, Yue-Qin; Zhou, Hui; Liu, Yi-Fei; Wang, Xiu-Ling; Papenfuss, Theodore J.; Wake, David B.; Qu, Liang-Hu

    2006-01-01

    We sequenced 15 complete mitochondrial genomes and performed comprehensive molecular phylogenetic analyses to study the origin and phylogeny of the Hynobiidae, an ancient lineage of living salamanders. Our phylogenetic analyses show that the Hynobiidae is a clade with well resolved relationships, and our results contrast with a morphology-based phylogenetic hypothesis. These salamanders have low vagility and are limited in their distribution primarily by deserts, mountains, and oceans. Our analysis suggests that the relationships among living hynobiids have been shaped primarily by geography. We show that four-toed species assigned to Batrachuperus do not form a monophyletic group, and those that occur in Afghanistan and Iran are transferred to the resurrected Paradactylodon. Convergent morphological characters in different hynobiid lineages are likely produced by similar environmental selective pressures. Clock-independent molecular dating suggests that hynobiids originated in the Middle Cretaceous [≈110 million years ago (Mya)]. We propose an “out of North China” hypothesis for hynobiid origins and hypothesize an ancestral stream-adapted form. Given the particular distributional patterns and our molecular dating estimates, we hypothesize that: (i) the interior desertification from Mongolia to Western Asia began ≈50 Mya; (ii) the Tibetan plateau (at least on the eastern fringe) experienced rapid uplift ≈40 Mya and reached an altitude of at least 2,500 m; and (iii) the Ailao–Red River shear zone underwent the most intense orogenic movement ≈24 Mya. PMID:16648252

  13. Sensitivity of two salamander (Ambystoma) species to ultraviolet radiation

    USGS Publications Warehouse

    Calfee, R.D.; Bridges, C.M.; Little, E.E.

    2006-01-01

    Increased ultraviolet-B (UV-B) radiation reaching the Earth's surface has been implicated in amphibian declines. Recent studies have shown that many amphibian species have differences in sensitivity depending on developmental stage. Embryos and larvae of Ambystoma maculatum (Spotted Salamander) and larvae of Ambystoma talpoideum (Mole Salamander) were exposed to five simulated UV-B treatments in controlled laboratory experiments to determine the relative sensitivity of different lifestages. Hatching success of the embryos exceeded 95% in all treatments; however, the larvae of both species exhibited greater sensitivity to UV-B exposure. Older larvae of A. maculatum that were not exposed to UV-B as embryos were more sensitive than larvae that had hatched during exposure to UV-B. Growth of surviving larvae of A. maculatum was significantly reduced as UV-B intensity increased, whereas growth of A. talpoideum was unaffected. These results were compared to ambient UV-B conditions in natural environments. It appears that the embryo stage is relatively unaffected by UV-B levels observed in natural habitats, probably because of protection from vegetation, organic matter in the water column, oviposition depth, and egg jelly. The larval stage of these species may be at greater risk, particularly if there is an increase in UV-B radiation exposure caused by increases in water clarity and/or decreases in dissolved organic carbon.

  14. Population dynamics and regulation in the cave salamander Speleomantes strinatii

    NASA Astrophysics Data System (ADS)

    Salvidio, Sebastiano

    2007-05-01

    Time series analysis has been used to evaluate the mechanisms regulating population dynamics of mammals and insects, but has been rarely applied to amphibian populations. In this study, the influence of endogenous (density-dependent) and exogenous (density-independent) factors regulating population dynamics of the terrestrial plethodontid salamander Speleomantes strinatii was analysed by means of time series and multiple regression analyses. During the period 1993 2005, S. strinatii population abundance, estimated by a standardised temporary removal method, displayed relatively low fluctuations, and the autocorrelation function (ACF) analysis showed that the time series had a noncyclic structure. The partial rate correlation function (PRCF) indicated that a strong first-order negative feedback dominated the endogenous dynamics. Stepwise multiple regression analysis showed that the only climatic factor influencing population growth rate was the minimum winter temperature. Thus, at least during the study period, endogenous, density-dependent negative feedback was the main factor affecting the growth rate of the salamander population, whereas stochastic environmental variables, such as temperature and rainfall, seemed to play a minor role in regulation. These results stress the importance of considering both exogenous and endogenous factors when analysing amphibian long-term population dynamics.

  15. Conservation genetics of the endangered Shenandoah salamander (Plethodon shenandoah, Plethodontidae)

    USGS Publications Warehouse

    Carpenter, D.W.; Jung, R.E.; Sites, J.W., Jr.

    2001-01-01

    The Shenandoah salamander (Plethodon shenandoah) is restricted to three isolated talus outcrops in Shenandoah National Park, VA, USA and has one of the smallest ranges of any tetrapod vertebrate. This species was listed as endangered under the US Endangered Species Act in 1989 over concern that direct competition with the red-backed salamander (Plethodon cinereus), successional habitat changes, and human impacts may cause its decline and possible extinction. We address two issues herein: (1) whether extensive introgression (through long-term hybridization) is present between the two species and threatens the survival of P. shenandoah, and (2) the level of population structure within P. shenandoah. We provide evidence from mtDNA haplotypes that shows no genetic differentiation among the three isolates of P. shenandoah, suggesting that their fragmentation is a geologically recent event, and/or that the isolates are still connected by occasional gene flow. There is also no evidence for extensive introgression of alleles in either direction between P. cinereus and P. shenandoah, which suggests that P. shenandoah may not be in danger of being genetically swamped out through hybridization with P. cinereus.

  16. Prevention

    MedlinePlus

    ... our e-newsletter! Aging & Health A to Z Prevention Basic Facts & Information Some factors that affect your ... control of the things that you can change. Preventive Recommendations for Adults Aged 65 and Older The ...

  17. [Phylogenetic relationships among Asiatic salamanders of the genus Salamandrella based on variability of nuclear genes].

    PubMed

    Maliarchuk, B A; Derenko, M V; Denisova, G A

    2015-01-01

    Based on sequence variation of three nuclear genome genes (BDNF, POMC, and RAG1), the phylogenetic relationships among Asiatic salamanders of the genus Salamandrella, Siberian salamander (S. keyserlingii) and Schrenk salamander (S. schrenkii), were examined. Both species demonstrated high levels of heterozygosity determined by intraspecific polymorphism. Fixed interspecific differences were revealed at one nucleotide position of the RAG1 gene, and thus the level of interspecific divergence over the three genes constituted only 0.04%. Analysis of the RAG1 polymorphism across the whole range of S. keyserlingii showed that only one gene variant, encoding for modified RAG1 recombinase, had the highest distribution to the north of the Amur region (west and northeast of Siberia). It is possible that the changes in the RAG1 gene in Siberian salamander are of an adaptive nature. However, cases of interspecific hybridization were identified in Jewish autonomous oblast (JAO), which contains one of the range borders between the two Salamandrella species. PMID:25857197

  18. Larval salamanders and channel geomorphology are indicators of hydrologic permanence in forested headwater streams

    EPA Science Inventory

    Regulatory agencies need rapid indicators of hydrologic permanence for jurisdictional determinations of headwater streams. Our study objective was to assess the utility of larval salamander presence and assemblage structure and habitat variables for determining stream permanence ...

  19. SPATIALLY AUTOCORRELATED DEMOGRAPHY AND INTERPOND MIGRATION IN THE CALIFORNIA TIGER SALAMANDER (AMBYSTOME CALIFORNIENSE)

    EPA Science Inventory

    We investigated the metapopulation structure of the California tiger salamander (Ambystoma californiense) using a combination of indirect and direct methods to evaluate two key requirements of modern metapopulation models: 1) that patches support somewhat independent populations ...

  20. Tiger salamanders' (Ambystoma tigrinum) response learning and usage of visual cues.

    PubMed

    Kundey, Shannon M A; Millar, Roberto; McPherson, Justin; Gonzalez, Maya; Fitz, Aleyna; Allen, Chadbourne

    2016-05-01

    We explored tiger salamanders' (Ambystoma tigrinum) learning to execute a response within a maze as proximal visual cue conditions varied. In Experiment 1, salamanders learned to turn consistently in a T-maze for reinforcement before the maze was rotated. All learned the initial task and executed the trained turn during test, suggesting that they learned to demonstrate the reinforced response during training and continued to perform it during test. In a second experiment utilizing a similar procedure, two visual cues were placed consistently at the maze junction. Salamanders were reinforced for turning towards one cue. Cue placement was reversed during test. All learned the initial task, but executed the trained turn rather than turning towards the visual cue during test, evidencing response learning. In Experiment 3, we investigated whether a compound visual cue could control salamanders' behaviour when it was the only cue predictive of reinforcement in a cross-maze by varying start position and cue placement. All learned to turn in the direction indicated by the compound visual cue, indicating that visual cues can come to control their behaviour. Following training, testing revealed that salamanders attended to stimuli foreground over background features. Overall, these results suggest that salamanders learn to execute responses over learning to use visual cues but can use visual cues if required. Our success with this paradigm offers the potential in future studies to explore salamanders' cognition further, as well as to shed light on how features of the tiger salamanders' life history (e.g. hibernation and metamorphosis) impact cognition. PMID:26796198

  1. Reintroduction and Post-Release Survival of a Living Fossil: The Chinese Giant Salamander

    PubMed Central

    Zhang, Lu; Jiang, Wei; Wang, Qi-Jun; Zhao, Hu; Zhang, Hong-Xing; Marcec, Ruth M.; Willard, Scott T.; Kouba, Andrew J.

    2016-01-01

    Captive rearing and reintroduction / translocation are increasingly used as tools to supplement wild populations of threatened species. Reintroducing captive-reared Chinese giant salamanders may help to augment the declining wild populations and conserve this critically endangered amphibian. We released 31 captive-reared juvenile giant salamanders implanted with VHF radio transmitters at the Heihe River (n = 15) and the Donghe River (n = 16) in the Qinling Mountains of central China. Salamanders were monitored every day for survival from April 28th 2013 to September 3rd 2014. We attempted to recapture all living individuals by the end of the study, measured their body mass and total body length, and checked for abnormalities and presence of external parasites. Two salamanders at the Heihe River and 10 animals at the Donghe River survived through the project timeline. Nine salamanders were confirmed dead, while the status of the other 10 animals was undetermined. The annual survival rate of giant salamanders at the Donghe River (0.702) was 1.7-fold higher than that at the Heihe River (0.405). Survival increased as individuals were held longer following surgery, whereas body mass did not have a significant impact on survival rate. All salamanders recaptured from the Donghe River (n = 8) increased in mass (0.50 ± 0.13 kg) and length (5.5 ± 1.5 cm) after approximately 11 months in the wild, and they were only 7% lighter than wild animals of the same length (mean residual = -0.033 ± 0.025). Our results indicate that captive-reared Chinese giant salamanders can survive in the wild one year after release and adequate surgical recovery time is extremely important to post-release survival. Future projects may reintroduce older juveniles to achieve better survival and longer monitoring duration. PMID:27258650

  2. Reintroduction and Post-Release Survival of a Living Fossil: The Chinese Giant Salamander.

    PubMed

    Zhang, Lu; Jiang, Wei; Wang, Qi-Jun; Zhao, Hu; Zhang, Hong-Xing; Marcec, Ruth M; Willard, Scott T; Kouba, Andrew J

    2016-01-01

    Captive rearing and reintroduction / translocation are increasingly used as tools to supplement wild populations of threatened species. Reintroducing captive-reared Chinese giant salamanders may help to augment the declining wild populations and conserve this critically endangered amphibian. We released 31 captive-reared juvenile giant salamanders implanted with VHF radio transmitters at the Heihe River (n = 15) and the Donghe River (n = 16) in the Qinling Mountains of central China. Salamanders were monitored every day for survival from April 28th 2013 to September 3rd 2014. We attempted to recapture all living individuals by the end of the study, measured their body mass and total body length, and checked for abnormalities and presence of external parasites. Two salamanders at the Heihe River and 10 animals at the Donghe River survived through the project timeline. Nine salamanders were confirmed dead, while the status of the other 10 animals was undetermined. The annual survival rate of giant salamanders at the Donghe River (0.702) was 1.7-fold higher than that at the Heihe River (0.405). Survival increased as individuals were held longer following surgery, whereas body mass did not have a significant impact on survival rate. All salamanders recaptured from the Donghe River (n = 8) increased in mass (0.50 ± 0.13 kg) and length (5.5 ± 1.5 cm) after approximately 11 months in the wild, and they were only 7% lighter than wild animals of the same length (mean residual = -0.033 ± 0.025). Our results indicate that captive-reared Chinese giant salamanders can survive in the wild one year after release and adequate surgical recovery time is extremely important to post-release survival. Future projects may reintroduce older juveniles to achieve better survival and longer monitoring duration. PMID:27258650

  3. Diagnostic and molecular evaluation of three iridovirus-associated salamander mortality events

    USGS Publications Warehouse

    Docherty, D.E.; Meteyer, C.U.; Wang, Jingyuan; Mao, J.; Case, S.T.; Chinchar, V.G.

    2003-01-01

    In 1998 viruses were isolated from tiger salamander larvae (Ambystoma tigrinum diaboli and A. tigrinum melanostictum) involved in North Dakota and Utah (USA) mortality events and spotted salamander (A. maculatum) larvae in a third event in Maine (USA). Although sympatric caudates and anurans were present at all three sites only ambystomid larvae appeared to be affected. Mortality at the North Dakota site was in the thousands while at the Utah and Maine sites mortality was in the hundreds. Sick larvae were lethargic and slow moving. They swam in circles with obvious buoyancy problems and were unable to remain upright. On the ventral surface, near the gills and hind limbs, red spots or swollen areas were noted. Necropsy findings included: hemorrhages and ulceration of the skin, subcutaneous and intramuscular edema, swollen and pale livers with multifocal hemorrhage, and distended fluid-filled intestines with areas of hemorrhage. Light microscopy revealed intracytoplasmic inclusions, suggestive of a viral infection, in a variety of organs. Electron microscopy of ultra thin sections of the same tissues revealed iridovirus-like particles within the inclusions. These viruses were isolated from a variety of organs, indicating a systemic infection. Representative viral isolates from the three mortality events were characterized using molecular assays. Characterization confirmed that the viral isolates were iridoviruses and that the two tiger salamander isolates were similar and could be distinguished from the spotted salamander isolate. The spotted salamander isolate was similar to frog virus 3, the type species of the genus Ranavirus, while the tiger salamander isolates were not. These data indicate that different species of salamanders can become infected and die in association with different iridoviruses. Challenge assays are required to determine the fish and amphibian host range of these isolates and to assess the susceptibility of tiger and spotted salamanders to

  4. Plethodon cinerius (eastern red-backed salamander) movement

    USGS Publications Warehouse

    Sterrett, Sean; Brand, Adrianne; Fields, William R.; Katz, Rachel A.; Grant, Evan H. Campbell

    2015-01-01

    Lungless salamanders (family Plethodontidae) are relatively sedentary and are presumed to have limited dispersal ability (Marsh et al. 2004. Ecology 85:3396–3405). Site fidelity in Plethodontidae is high, and individuals displaced 90 m return to home territories (Kleeberger and Werner 1982. Copeia 1982:409–415). Individuals defend territories (Jaeger et al. 1982. Anim. Behav. 30:490–496) and female home ranges have been estimated to be 24.34 m2 (Kleeberger and Werner 1982, op. cit.). Females may seek out suitable subsurface habitat to oviposit eggs, yet little is known about their maximum movement distances (Petranka 1998. Salamanders of the United States and Canada. Smithsonian Institution Press, Washington. 587 pp.).On 18 September 2014, a female P. cinereus (lead back morphotype; SVL = 44.68 mm; 0.89 g) was found under a coverboard during a standard sampling event and uniquely marked using visual implant elastomer at the S.O. Conte Anadromous Fish Research Center, Massachusetts, USA (42.59280°N, 72.58070°W, datum WGS84; elev. 74 m). This individual was subsequently recaptured at ~1500 h on 8 October 2014 under a coverboard within 3 m of the original capture location and then again ~1430 h on 16 October 2014 under a log, within the same forest patch, though in a 50 x 150 m area adjacent to the original study area. Because we found the marked salamander while collecting multiple individuals for a laboratory study, the exact recapture location of the marked individual is not known. However, the distance between the 8 October capture location and the nearest edge of the 16 October search area (i.e. 50 x 150 m) was 143 m, indicating a minimum movement distance. As far as we are aware, this is the longest recorded movement for P. cinereus by more than 53 m (Kleeberger and Werner 1982, op. cit.). This finding followed a rain event of 1.63 cm within 24 h and the second largest sustained rain event during October. The movement we observed may have been due to

  5. Three decades of urbanization: Estimating the impact of land-cover change on stream salamander populations

    USGS Publications Warehouse

    Price, S.J.; Dorcas, M.E.; Gallant, A.L.; Klaver, R.W.; Willson, J.D.

    2006-01-01

    Urbanization has become the dominant form of landscape disturbance in parts of the United States. Small streams in the Piedmont region of the eastern United States support high densities of salamanders and are often the first habitats to be affected by landscape-altering factors such as urbanization. We used US Geological Survey land cover data from 1972 to 2000 and a relation between stream salamanders and land cover, established from recent research, to estimate the impact of contemporary land-cover change on the abundance of stream salamanders near Davidson, North Carolina, a Piedmont locale that has experienced rapid urbanization during this time. Our analysis indicates that southern two-lined salamander (Eurycea cirrigera) populations have decreased from 32% to 44% while northern dusky salamanders (Desmognathus fuscus) have decreased from 21% to 30% over the last three decades. Our results suggest that the widespread conversion of forest to urban land in small catchments has likely resulted in a substantial decline of populations of stream salamanders and could have serious effects on stream ecosystems. ?? 2006 Elsevier Ltd. All rights reserved.

  6. Spatial variation in water loss predicts terrestrial salamander distribution and population dynamics.

    PubMed

    Peterman, W E; Semlitsch, R D

    2014-10-01

    Many patterns observed in ecology, such as species richness, life history variation, habitat use, and distribution, have physiological underpinnings. For many ectothermic organisms, temperature relationships shape these patterns, but for terrestrial amphibians, water balance may supersede temperature as the most critical physiologically limiting factor. Many amphibian species have little resistance to water loss, which restricts them to moist microhabitats, and may significantly affect foraging, dispersal, and courtship. Using plaster models as surrogates for terrestrial plethodontid salamanders (Plethodon albagula), we measured water loss under ecologically relevant field conditions to estimate the duration of surface activity time across the landscape. Surface activity time was significantly affected by topography, solar exposure, canopy cover, maximum air temperature, and time since rain. Spatially, surface activity times were highest in ravine habitats and lowest on ridges. Surface activity time was a significant predictor of salamander abundance, as well as a predictor of successful recruitment; the probability of a juvenile salamander occupying an area with high surface activity time was two times greater than an area with limited predicted surface activity. Our results suggest that survival, recruitment, or both are demographic processes that are affected by water loss and the ability of salamanders to be surface-active. Results from our study extend our understanding of plethodontid salamander ecology, emphasize the limitations imposed by their unique physiology, and highlight the importance of water loss to spatial population dynamics. These findings are timely for understanding the effects that fluctuating temperature and moisture conditions predicted for future climates will have on plethodontid salamanders. PMID:25154754

  7. Thermal equilibrium and temperature differences among body regions in European plethodontid salamanders.

    PubMed

    Lunghi, Enrico; Manenti, Raoul; Canciani, Giancarlo; Scarì, Giorgio; Pennati, Roberta; Ficetola, Gentile Francesco

    2016-08-01

    Information on species thermal physiology is extremely important to understand species responses to environmental heterogeneity and changes. Thermography is an emerging technology that allows high resolution and accurate measurement of body temperature, but until now it has not been used to study thermal physiology of amphibians in the wild. Hydromantes terrestrial salamanders are strongly depending on ambient temperature for their activity and gas exchanges, but information on their body temperature is extremely limited. In this study we tested if Hydromantes salamanders are thermoconform, we assessed whether there are temperature differences among body regions, and evaluated the time required to reach the thermal equilibrium. During summers of 2014 and 2015 we analysed 56 salamanders (Hydromantes ambrosii and Hydromantes italicus) using infrared thermocamera. We photographed salamanders at the moment in which we found them and 1, 2, 3, 4, 5 and 15min after having kept them in the hands. Body temperature was equal to air temperature; salamanders attained the equilibrium with air temperature in about 8min, the time required to reach equilibrium was longer in individuals with large body size. We detected small temperature differences between body parts, the head being slightly warmer than the body and the tail (mean difference: 0.05°C). These salamanders quickly reach the equilibrium with the environment, thus microhabitat measurement allows obtaining accurate information on their tolerance limits. PMID:27503719

  8. Soil acidity affects distribution, behavior, and physiology of the salamander Plethodon cinereus

    SciTech Connect

    Wyman, R.L.; Hawksley-Lescault, D.S.

    1987-12-01

    Censuses at two sites in Delaware County, New York from spring 1981 through spring 1985 indicated that the density and distribution of Plethodon cinereus were influenced by soil pH but not by soil temperature or moisture. Of 1044 1-m/sup 2/ quadrats of forest litter searched, 284 had a pH of 3.7 or less and only 25 of these (8.8%) contained salamanders. Of 760 quadrats with a pH 3.8 or more, 386 (50.8%) contained salamanders. Juvenile salamanders were never found on soils with a pH less than or equal to 3.7. Seasonal salamander density was correlated (r = -0.92) with the percentage of quadrats with a pH of 3.7 and less. Salamanders apparently were excluded from 27% of forest habitat because of low soil pH. In the laboratory, P. cinereus preferred to occupy substrates near neutral pH when given a choice among three levels of substrate acidity. The acutely lethal pH was between 2.5 and 3 and the 8-mo chronically lethal pH was between 3 and 4. Growth and respiration were reduced at low pHs. The influence of soil pH on salamander distribution might fundamentally change the forest floor decomposer food web of which P. cinereus is an upper-level consumer.

  9. Leaf litter bags as an index to populations of northern two-lined salamanders (Eurycea bislineata)

    USGS Publications Warehouse

    Chalmers, R.J.; Droege, S.

    2002-01-01

    Concern about recent amphibian declines has led to research on amphibian populations, but few statistically tested, standardized methods of counting amphibians exist. We tested whether counts of northern two-lined salamander larvae (Eurycea bislineata) sheltered in leaf litter bags--a relatively new, easily replicable survey technique--had a linear correlation to total number of larvae. Using experimental enclosures placed in streams, we compared number of salamanders found in artificial habitat (leaf litter bags) with total number of salamanders in each enclosure. Low numbers of the animals were found in leaf litter bags, and the relative amount of variation in the index (number of animals in leaf litter bags compared to total number of animals in stream enclosures) was high. The index of salamanders in leaf litter bags was not significantly related to total number of salamanders in enclosures for two-thirds of the replicates or with pooled replicates (P= 0.066). Consequently, we cannot recommend using leaf litter bags to index populations of northern two-lined salamanders.

  10. A re-examination and re-evaluation of salamander orbital glands.

    PubMed

    Rehorek, Susan J; Grand-Pierre, Alix E; Cummings, Joshua R; Jewell, Bridgette; Constantine, Julieanne; Hillenius, W Jaap

    2013-11-01

    The amphibian integument contains numerous multicellular glands. Although two of these, the nasolabial and orbital glands and the associated nasolacrimal duct (NLD), have historically received considerable attention, interpretation of the original observations can be problematic in the context of current literature. Salamanders, in particular, are frequently regarded as at least indicative of aspects of the morphology of the common ancestor to all extant tetrapods; hence, an understanding of these glands in salamanders might prove to be informative about their evolution. For this study, the orbitonasal region of salamanders from three families was histologically examined. Three themes emerged: (1) examination of the effect of phylogeny on the nasolabial gland and NLD revealed a combination of features that may be unique to plethodontid salamanders, and may be correlated to their nose-tapping behavior by which substances are moved into the vomeronasal organ; (2) ecology appears to impact the relative development of the orbital glands, but not necessarily the nasolabial gland, with smaller glands being present in the aquatic species; (3) the nomenclature of the salamander orbital gland remains problematic, especially in light of comparative studies, as several alternate possibilities are viable. From this nomenclatural conundrum, however, it could be concluded that there may be a global pattern in the location of tetrapod orbital gland development. Molecular questions in terms of ontogeny and genetic homology affect the nature of the debate on orbital gland nomenclature. These observations suggest that rather than reflecting an ancestral condition, salamanders may instead represent a case of specialized, convergent evolution. PMID:24106029

  11. Psychiatric morbidity among prisoners

    PubMed Central

    Ayirolimeethal, Anithakumari; Ragesh, G.; Ramanujam, Jayanthi M.; George, Biju

    2014-01-01

    Background: There is a considerable lack of scientific estimate of psychiatric morbidity among Indian prisoners. Objective: The objective of the following study is to study the prevalence of psychiatric morbidity among prisoners. Settings and Design: A cross-sectional study at District Jail, Kozhikode, Kerala. Materials and Methods: A total of 255 prisoners who were inmates during the period from mid-April to mid-July 2011 participated in the study. The study subjects included both male and female remand or convict prisoners. Socio-demographic data, clinical history and criminological history were collected from each individual. Psychiatric morbidity was assessed using MINI-Plus. Statistical Analysis: Done by using SPSS version 16 (SPSS Inc, Chicago, USA). Results: A total of 175 subjects (68.6%) had a current mental illness. Substance use disorder was the most common diagnosis (47.1%). Antisocial personality disorder was diagnosed in 19.2%, adjustment disorder in 13.7%, mood disorder in 4.3% and psychosis in another 6.3% of prisoners. A high rate of a current psychiatric disorder was seen in male (69.7%) prisoners. A significant association was noticed for the different nature of crimes with psychiatric diagnoses and previous imprisonment. Nearly 4% of prisoners reported a moderate to high suicide risk. Conclusion: Mental health problems among prisoners were quite high. Mentally ill prisoners are at high risk for repeated incarceration. The increased rate of psychiatric disorders should be a concern for mental health professionals and the policy makers. PMID:24891702

  12. Epizootiology of sixty-four amphibian morbidity and mortality events in the USA, 1996-2001

    USGS Publications Warehouse

    Green, D.E.; Converse, K.A.; Schrader, A.K.

    2002-01-01

    A total of 44 amphibian mortality events and 20 morbidity events were reviewed retrospectively. The most common cause of amphibian mortality events was infection by ranaviruses (Family: Iridoviridae). Ranavirus epizootics have abrupt onset and affect late-stage larvae and recent metamorphs. Mortality events due to ranavirus infections affected only widespread and abundant amphibian species, and there was a clear association with high population densities. Chytrid fungal infections accounted for seven mortality events in postmetamorphic anurans only. Chytrid epizootics are insidious and easily overlooked in the field. While both ranavirus and chytrid fungal epizootics were associated with >90% mortality rates at affected sites, only the chytrid fungal infections were linked to multiple amphibian population declines. Three primitive fungal organisms in the newly erected clade, Mesomycetozoa, caused morbidities and mortalities in anurans and salamanders.

  13. Epizootiology of sixty-four amphibian morbidity and mortality events in the USA, 1996-2001

    USGS Publications Warehouse

    Green, D.E.; Converse, K.A.; Schrader, Audra K.

    2002-01-01

    A total of 44 amphibian mortality events and 20 morbidity events were reviewed retrospectively. The most common cause of amphibian mortality events was infection by ranaviruses (Family: Iridoviridae). Ranavirus epizootics have abrupt onset and affect late-stage larvae and recent metamorphs. Mortality events due to ranavirus infections affected only widespread and abundant amphibian species, and there was a clear association with high population densities. Chytrid fungal infections accounted for seven mortality events in postmetamorphic anurans only. Chytrid epizootics are insidious and easily overlooked in the field. While both ranavirus and chytrid fungal epizootics were associated with > 90% mortality rates at affected sites, only the chytrid fungal infections were linked to multiple amphibian population declines. Three primitive fungal organisms in the newly erected clade, Mesomycetozoa, caused morbidities and mortalities in anurans and salamanders.

  14. Road deicing salt irreversibly disrupts osmoregulation of salamander egg clutches.

    PubMed

    Karraker, Nancy E; Gibbs, James P

    2011-03-01

    It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations. PMID:21147507

  15. Ambient ultraviolet radiation causes mortality in salamander eggs

    SciTech Connect

    Blaustein, A.R.; Edmond, B.; Kiesecker, J.M.

    1995-08-01

    Previous research has shown that amphibian species have differential sensitivity to ultraviolet-B (UV-B) radiation. In some anuran species, ambient levels of UV-B cause mortality in embryonic stages and hatching success is significantly reduced. Projected increases in UV-B may affect an increasing number of species. The adverse effects of UV-B may eventually be manifested at the population level and may ultimately contribute to population declines. Using field experiments, we investigated the effects of ambient UV-B on salamander (Ambystoma gracile) embryos developing at natural oviposition sites. We show that the hatching success of eggs of A. gracile shielded from UV-B is significantly higher than those not shielded from UV-B. 27 refs., 1 fig.

  16. Morbidity and Mortality Weekly Report. Volume 61, Number 31

    ERIC Educational Resources Information Center

    Moolenaar, Ronald L., Ed.

    2012-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  17. Morbidity and Mortality Weekly Report. Volume 61, Number 13

    ERIC Educational Resources Information Center

    Moolenaar, Ronald L., Ed.

    2012-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  18. Morbidity and Mortality Weekly Report. Volume 60, Number 15

    ERIC Educational Resources Information Center

    Moolenaar, Ronald L., Ed.

    2011-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  19. Morbidity and Mortality Weekly Report. Volume 60, Number 23

    ERIC Educational Resources Information Center

    Centers for Disease Control and Prevention, 2011

    2011-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  20. Morbidity and Mortality Weekly Report. Volume 61, Number 17

    ERIC Educational Resources Information Center

    Moolenaar, Ronald L., Ed.

    2012-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  1. The New Morbidity: A National Plan of Action.

    ERIC Educational Resources Information Center

    Baumeister, Alfred A.; And Others

    1991-01-01

    Discusses child morbidity, suggesting solutions can be found at the community level. Argues the federal government's role is essential in articulating policy and providing resources. Generates a new morbidity model emphasizing poverty and social factors as crucial influences. Lists priorities for effective, preventive, intervention planning. (NL)

  2. Morbidity and Mortality Weekly Report. Volume 61, Number 33

    ERIC Educational Resources Information Center

    Moolenaar, Ronald L., Ed.

    2012-01-01

    The "Morbidity and Mortality Weekly Report" ("MMWR") Series is prepared by the Centers for Disease Control and Prevention (CDC). Data presented by the Notifiable Disease Data Team and 122 Cities Mortality Data Team in the weekly "MMWR" are provisional, based on weekly reports to CDC by state health departments. This issue of "Morbidity and…

  3. Declines in woodland salamander abundance associated with non-native earthworm and plant invasions.

    PubMed

    Maerz, John C; Nuzzo, Victoria A; Blossey, Bernd

    2009-08-01

    Factors that negatively affect the quality of wildlife habitat are a major concern for conservation. Non-native species invasions, in particular, are perceived as a global threat to the quality of wildlife habitat. Recent evidence indicates that some changes to understory plant communities in northern temperate forests of North America, including invasions by 3 non-native plant species, are facilitated by non-native earthworm invasion. Furthermore, non-native earthworm invasions cause a reduction in leaf litter on the forest floor, and the loss of forest leaf litter is commonly associated with declines in forest fauna, including amphibians. We conducted a mark-recapture study of woodland salamander abundance across plant invasion fronts at 10 sites to determine whether earthworm or plant invasions were associated with reduced salamander abundance. Salamander abundance declined exponentially with decreasing leaf litter volume. There was no significant relationship between invasive plant cover and salamander abundance, independent of the effects of leaf litter loss due to earthworm invasion. An analysis of selected salamander prey abundance (excluding earthworms) at 4 sites showed that prey abundance declined with declining leaf litter. The loss of leaf litter layers due to non-native earthworm invasions appears to be negatively affecting woodland salamander abundance, in part, because of declines in the abundance of small arthropods that are a stable resource for salamanders. Our results demonstrate that earthworm invasions pose a significant threat to woodland amphibian fauna in the northeastern United States, and that plant invasions are symptomatic of degraded amphibian habitat but are not necessarily drivers of habitat degradation. PMID:19236449

  4. Prevention

    MedlinePlus

    ... Prevention Treatment 2003 U.S. Outbreak African Rodent Importation Ban For Clinicians Clinical Recognition Specimen Collection Treatment Smallpox ... Examining Animals with Suspected Monkeypox African Rodent Importation Ban Resources Related Links Poxvirus Molluscum Contagiosum Orf Virus ( ...

  5. Mortality, Morbidity, and Developmental Outcomes in Infants Born to Women Who Received Either Mefloquine or Sulfadoxine-Pyrimethamine as Intermittent Preventive Treatment of Malaria in Pregnancy: A Cohort Study

    PubMed Central

    Rupérez, María; González, Raquel; Mombo-Ngoma, Ghyslain; Kabanywanyi, Abdunoor M.; Sevene, Esperança; Ouédraogo, Smaïla; Kakolwa, Mwaka A.; Vala, Anifa; Accrombessi, Manfred; Briand, Valérie; Aponte, John J.; Manego Zoleko, Rella; Adegnika, Ayôla A.; Cot, Michel; Kremsner, Peter G.; Massougbodji, Achille; Abdulla, Salim; Ramharter, Michael; Macete, Eusébio; Menéndez, Clara

    2016-01-01

    Background Little is known about the effects of intermittent preventive treatment of malaria in pregnancy (IPTp) on the health of sub-Saharan African infants. We have evaluated the safety of IPTp with mefloquine (MQ) compared to sulfadoxine-pyrimethamine (SP) for important infant health and developmental outcomes. Methods and Findings In the context of a multicenter randomized controlled trial evaluating the safety and efficacy of IPTp with MQ compared to SP in pregnancy carried out in four sub-Saharan countries (Mozambique, Benin, Gabon, and Tanzania), 4,247 newborns, 2,815 born to women who received MQ and 1,432 born to women who received SP for IPTp, were followed up until 12 mo of age. Anthropometric parameters and psychomotor development were assessed at 1, 9, and 12 mo of age, and the incidence of malaria, anemia, hospital admissions, outpatient visits, and mortality were determined until 12 mo of age. No significant differences were found in the proportion of infants with stunting, underweight, wasting, and severe acute malnutrition at 1, 9, and 12 mo of age between infants born to women who were on IPTp with MQ versus SP. Except for three items evaluated at 9 mo of age, no significant differences were observed in the psychomotor development milestones assessed. Incidence of malaria, anemia, hospital admissions, outpatient visits, and mortality were similar between the two groups. Information on the outcomes at 12 mo of age was unavailable in 26% of the infants, 761 (27%) from the MQ group and 377 (26%) from the SP group. Reasons for not completing the study were death (4% of total study population), study withdrawal (6%), migration (8%), and loss to follow-up (9%). Conclusions No significant differences were found between IPTp with MQ and SP administered in pregnancy on infant mortality, morbidity, and nutritional outcomes. The poorer performance on certain psychomotor development milestones at 9 mo of age in children born to women in the MQ group compared

  6. IMPACT OF GUTHION ON SURVIVAL AND GROWTH OF THE FROG PSEUDACRIS REGILLA AND THE SALAMANDERS AMBYSTOMA GRACILE AND AMBYSTOMA MACULATUM

    EPA Science Inventory

    The effects of the insecticides Guthion (technical grade) and Guthion 2S(commercial formulation) on survival and growth of tadpoles of the Pacific treefrog Pseudacris regilla, and larvae of the Northwestern salamander Ambystoma gracile and the spotted salamander Ambystoma macula...

  7. 76 FR 44036 - Proposed Low-Effect Habitat Conservation Plan for the California Tiger Salamander, AT&T Portable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... Salamander, AT&T Portable Generator Storage Facility, Yolo County, CA AGENCY: Fish and Wildlife Service... the construction of a portable generator storage facility located at 26120 County Road 6, Dunnigan, CA... for the California tiger salamander into a new storage facility for portable generators within...

  8. Gastrointestinal Morbidity in Obesity

    PubMed Central

    Acosta, Andres; Camilleri, Michael

    2014-01-01

    Obesity is a complex disease that results from increased energy intake and decreased energy expenditure. The gastrointestinal system plays a key role in the pathogenesis of obesity and facilitates caloric imbalance. Changes in gastrointestinal hormones and the inhibition of mechanisms that curtail caloric intake result in weight gain. It is not clear if the gastrointestinal role in obesity is a cause or an effect of this disease. Obesity is often associated with type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVD). Obesity is also associated with gastrointestinal disorders, which are more frequent and present earlier than T2DM and CVD. Diseases such as gastro-esophageal reflux disease, cholelithiasis or non-alcoholic steatohepatitis are directly related to body weight and abdominal adiposity. Our objective is to assess the role of each gastrointestinal organ in obesity and the gastrointestinal morbidity resulting in those organs from effects of obesity. PMID:24602085

  9. Larval long-toed salamanders incur nonconsumptive effects in the presence of nonnative trout

    USGS Publications Warehouse

    Kenison, Erin K.; Litt, Andrea R.; Pilliod, David; McMahon, Thomas E.

    2016-01-01

    Predators can influence prey directly through consumption or indirectly through nonconsumptive effects (NCEs) by altering prey behavior, morphology, and life history. We investigated whether predator-avoidance behaviors by larval long-toed salamanders (Ambystoma macrodactylum) in lakes with nonnative trout result in NCEs on morphology and development. Field studies in lakes with and without trout were corroborated by experimental enclosures, where prey were exposed only to visual and chemical cues of predators. We found that salamanders in lakes with trout were consistently smaller than in lakes without trout: 38% lower weight, 24% shorter body length, and 29% shorter tail length. Similarly, salamanders in protective enclosures grew 2.9 times slower when exposed to visual and olfactory trout cues than when no trout cues were present. Salamanders in trout-free lakes and enclosures were 22.7 times and 1.48 times, respectively, more likely to metamorphose during the summer season than those exposed to trout in lakes and/or their cues. Observed changes in larval growth rate and development likely resulted from a facultative response to predator-avoidance behavior and demonstrate NCEs occurred even when predation risk was only perceived. Reduced body size and growth, as well as delayed metamorphosis, could have ecological consequences for salamander populations existing with fish if those effects carry-over into lower recruitment, survival, and fecundity.

  10. A case for using Plethodontid salamanders for monitoring biodiversity and ecosystem integrity of North American forests

    USGS Publications Warehouse

    Welsh, H.H., Jr.; Droege, S.

    2001-01-01

    Terrestrial salamanders of the family P!ethodontidae have unique attributes that make them excellent indicators of biodiversity and ecosystem integrity in forested habitats. Their longevity, small territory size, site fidelity, sensitivity to natural and anthropogenic perturbations, tendency to occur in high densities, and low sampling costs mean that counts of plethodontid salamanders provide numerous advantages over counts of other North American forest organisms for indicating environmental change. Furthermore, they are tightly linked physiologically to microclimatic and successional processes that influence the distribution and abundance of numerous other hydrophilic but difficult-to-study forest-dwelling plants and animals. Ecosystem processes such as moisture cycling, food-web dynamics, and succession, with their related structural and microclimatic variability, all affect forest biodiversity and have been shown to affect salamander populations as well. We determined the variability associated with sampling for plethodontid salamanders by estimating the coefficient of variation (CV) from available time-series data. The median coefficient of variation indicated that variation in counts of individuals among studies was much lower in plethodonticis (27%) than in lepidoptera (93%), passerine birds (57%), small mammals (69%), or other amphibians (37-46%), which means plethodontid salamanders provide an important statistical advantage over other species for monitoring long-term forest health.

  11. Estimating superpopulation size and annual probability of breeding for pond-breeding salamanders

    USGS Publications Warehouse

    Kinkead, K.E.; Otis, D.L.

    2007-01-01

    It has long been accepted that amphibians can skip breeding in any given year, and environmental conditions act as a cue for breeding. In this paper, we quantify temporary emigration or nonbreeding probability for mole and spotted salamanders (Ambystoma talpoideum and A. maculatum). We estimated that 70% of mole salamanders may skip breeding during an average rainfall year and 90% may skip during a drought year. Spotted salamanders may be more likely to breed, with only 17% avoiding the breeding pond during an average rainfall year. We illustrate how superpopulations can be estimated using temporary emigration probability estimates. The superpopulation is the total number of salamanders associated with a given breeding pond. Although most salamanders stay within a certain distance of a breeding pond for the majority of their life spans, it is difficult to determine true overall population sizes for a given site if animals are only captured during a brief time frame each year with some animals unavailable for capture at any time during a given year. ?? 2007 by The Herpetologists' League, Inc.

  12. Decoding the mechanisms of gait generation in salamanders by combining neurobiology, modeling and robotics.

    PubMed

    Bicanski, Andrej; Ryczko, Dimitri; Knuesel, Jérémie; Harischandra, Nalin; Charrier, Vanessa; Ekeberg, Örjan; Cabelguen, Jean-Marie; Ijspeert, Auke Jan

    2013-10-01

    Vertebrate animals exhibit impressive locomotor skills. These locomotor skills are due to the complex interactions between the environment, the musculo-skeletal system and the central nervous system, in particular the spinal locomotor circuits. We are interested in decoding these interactions in the salamander, a key animal from an evolutionary point of view. It exhibits both swimming and stepping gaits and is faced with the problem of producing efficient propulsive forces using the same musculo-skeletal system in two environments with significant physical differences in density, viscosity and gravitational load. Yet its nervous system remains comparatively simple. Our approach is based on a combination of neurophysiological experiments, numerical modeling at different levels of abstraction, and robotic validation using an amphibious salamander-like robot. This article reviews the current state of our knowledge on salamander locomotion control, and presents how our approach has allowed us to obtain a first conceptual model of the salamander spinal locomotor networks. The model suggests that the salamander locomotor circuit can be seen as a lamprey-like circuit controlling axial movements of the trunk and tail, extended by specialized oscillatory centers controlling limb movements. The interplay between the two types of circuits determines the mode of locomotion under the influence of sensory feedback and descending drive, with stepping gaits at low drive, and swimming at high drive. PMID:23430277

  13. Hybrid vigor between native and introduced salamanders raises new challenges for conservation

    PubMed Central

    Fitzpatrick, Benjamin M.; Shaffer, H. Bradley

    2007-01-01

    Hybridization between differentiated lineages can have many different consequences depending on fitness variation among hybrid offspring. When introduced organisms hybridize with natives, the ensuing evolutionary dynamics may substantially complicate conservation decisions. Understanding the fitness consequences of hybridization is an important first step in predicting its evolutionary outcome and conservation impact. Here, we measured natural selection caused by differential viability of hybrid larvae in wild populations where native California Tiger Salamanders (Ambystoma californiense) and introduced Barred Tiger Salamanders (Ambystoma tigrinum mavortium) have been hybridizing for 50–60 years. We found strong evidence of hybrid vigor; mixed-ancestry genotypes had higher survival rates than genotypes containing mostly native or mostly introduced alleles. Hybrid vigor may be caused by heterozygote advantage (overdominance) or recombinant hybrid vigor (due to epistasis or complementation). These genetic mechanisms are not mutually exclusive, and we find statistical support for both overdominant and recombinant contributions to hybrid vigor in larval tiger salamanders. Because recombinant homozygous genotypes can breed true, a single highly fit genotype with a mosaic of native and introduced alleles may eventually replace the historically pure California Tiger Salamander (listed as Threatened under the U.S. Endangered Species Act). The management implications of this outcome are complex: Genetically pure populations may not persist into the future, but average fitness and population viability of admixed California Tiger Salamanders may be enhanced. The ecological consequences for other native species are unknown. PMID:17884982

  14. Salamanders increase their feeding activity when infected with the pathogenic chytrid fungus Batrachochytrium dendrobatidis.

    PubMed

    Hess, Alexandra; McAllister, Caroline; DeMarchi, Joseph; Zidek, Makenzie; Murone, Julie; Venesky, Matthew D

    2015-10-27

    Immune function is a costly line of defense against parasitism. When infected with a parasite, hosts frequently lose mass due to these costs. However, some infected hosts (e.g. highly resistant individuals) can clear infections with seemingly little fitness losses, but few studies have tested how resistant hosts mitigate these costly immune defenses. We explored this topic using eastern red-backed salamanders Plethodon cinereus and the fungal pathogen Batrachochytrium dendrobatidis (Bd). Bd is generally lethal for amphibians, and stereotypical symptoms of infection include loss in mass and deficits in feeding. However, individuals of P. cinereus can clear their Bd infections with seemingly few fitness costs. We conducted an experiment in which we repeatedly observed the feeding activity of Bd-infected and non-infected salamanders. We found that Bd-infected salamanders generally increased their feeding activity compared to non-infected salamanders. The fact that we did not observe any differences in mass change between the treatments suggests that increased feeding might help Bd-infected salamanders minimize the costs of an effective immune response. PMID:26503775

  15. Asymmetric Introgression in a Spotted Salamander Hybrid Zone.

    PubMed

    Johnson, Benjamin B; White, Thomas A; Phillips, Christopher A; Zamudio, Kelly R

    2015-01-01

    Before the establishment of reproductive isolation, deeply diverged intraspecific lineages can experience complex genetic and behavioral interactions as they come into secondary contact. Divergent selective and demographic processes mediate gene flow among lineages, resulting in hybrid zones with complex biogeographic structure. Discordance in the biogeographic patterns of autosomal and maternally inherited loci provides a useful window to infer the processes mediating admixture and introgression across hybrid zones. Here, we sampled 489 genotypes across a hybrid zone between 2 phylogeographic lineages of the spotted salamander, Ambystoma maculatum, and characterize discordant patterns of nuclear and mitochondrial introgression across the contact boundary. Our results indicate asymmetric introgression of nuclear DNA beyond the contact boundary from the western to eastern lineage, with introgression of eastern mitochondrial DNA into the western lineage. We discuss alternative mechanisms for this pattern and attribute this result to neutral patterns of population expansion of the western lineage into the east in combination with female mate choice for larger-bodied western males. Our results underscore the complexity of interacting mechanisms that give rise to reproductive asymmetries in the earliest stages of the speciation process. PMID:26136297

  16. Phylogenetic history underlies elevational biodiversity patterns in tropical salamanders

    PubMed Central

    Wiens, John J; Parra-Olea, Gabriela; García-París, Mario; Wake, David B

    2007-01-01

    Elevational variation in species richness is ubiquitous and important for conservation, but remains poorly explained. Numerous studies have documented higher species richness at mid-elevations, but none have addressed the underlying evolutionary and biogeographic processes that ultimately explain this pattern (i.e. speciation, extinction and dispersal). Here, we address the evolutionary causes of the mid-elevational diversity hump in the most species-rich clade of salamanders, the tropical bolitoglossine plethodontids. We present a new phylogeny for the group based on DNA sequences from all 13 genera and 137 species. Using this phylogeny, we find no relationship between rates of diversification of clades and their elevational distribution, and no evidence for a rapid ‘species pump’ in tropical montane regions. Instead, we find a strong relationship between the number of species in each elevational zone and the estimated time when each elevational band was first colonized. Mid-elevation habitats were colonized early in the phylogenetic history of bolitoglossines, and given similar rates of diversification across elevations, more species have accumulated in the elevational zones that were inhabited the longest. This pattern may be widespread and suggests that mid-elevation habitats may not only harbour more species, but may also contain more phylogenetic diversity than other habitats within a region. PMID:17284409

  17. Pond acidification may explain differences in corticosterone among salamander populations.

    PubMed

    Chambers, David L; Wojdak, Jeremy M; Du, Pang; Belden, Lisa K

    2013-01-01

    Physiological tolerances play a key role in determining species distributions and abundance across a landscape, and understanding these tolerances can therefore be useful in predicting future changes in species distributions that might occur. Vertebrates possess several highly conserved physiological mechanisms for coping with environmental stressors, including the hormonal stress response that involves an endocrine cascade resulting in the increased production of glucocorticoids. We examined the function of this endocrine axis by assessing both baseline and acute stress-induced concentrations of corticosterone in larvae from eight natural breeding populations of Jefferson's salamander Ambystoma jeffersonianum. We surveyed individuals from each pond and also examined a variety of environmental pond parameters. We found that baseline and stress-induced corticosterone concentrations differed significantly among ponds. Population-level baseline corticosterone concentrations were negatively related to pH and positively related to nitrate, and stress-induced concentrations were again negatively related to pH, positively related to nitrate, and positively related to temperature. We followed the field survey with an outdoor mesocosm experiment in which we manipulated pH and again examined baseline and acute stress-induced corticosterone in A. jeffersonianum larvae. As in the field survey, we observed an increase in the baseline corticosterone concentration of individuals exposed to the lowest pH treatment (pH 5-5.8). Examining physiological indices using a combined approach of field surveys and experiments can be a powerful tool for trying to unravel the complexities of environmental impacts on species distributions. PMID:23434782

  18. Testicular structure and germ cells morphology in salamanders

    PubMed Central

    Uribe, Mari Carmen; Mejía-Roa, Víctor

    2014-01-01

    Testes of salamanders or urodeles are paired elongated organs that are attached to the dorsal wall of the body by a mesorchium. The testes are composed of one or several lobes. Each lobe is morphologically and functionally a similar testicular unit. The lobes of the testis are joined by cords covered by a single peritoneal epithelium and subjacent connective tissue. The cords contain spermatogonia. Spermatogonia associate with Sertoli cells to form spermatocysts or cysts. The spermatogenic cells in a cyst undergo their development through spermatogenesis synchronously. The distribution of cysts displays the cephalo-caudal gradient in respect to the stage of spermatogenesis. The formation of cysts at cephalic end of the testis causes their migration along the lobules to the caudal end. Consequently, the disposition in cephalo-caudal regions of spermatogenesis can be observed in longitudinal sections of the testis. The germ cells are spermatogonia, diploid cells with mitotic activity; primary and second spermatocytes characterized by meiotic divisions that develop haploid spermatids; during spermiogenesis the spermatids differentiate to spermatozoa. During spermiation the cysts open and spermatozoa leave the testicular lobules. After spermiation occurs the development of Leydig cells into glandular tissue. This glandular tissue regressed at the end of the reproductive cycle. PMID:26413406

  19. Wildlife disease. Recent introduction of a chytrid fungus endangers Western Palearctic salamanders.

    PubMed

    Martel, A; Blooi, M; Adriaensen, C; Van Rooij, P; Beukema, W; Fisher, M C; Farrer, R A; Schmidt, B R; Tobler, U; Goka, K; Lips, K R; Muletz, C; Zamudio, K R; Bosch, J; Lötters, S; Wombwell, E; Garner, T W J; Cunningham, A A; Spitzen-van der Sluijs, A; Salvidio, S; Ducatelle, R; Nishikawa, K; Nguyen, T T; Kolby, J E; Van Bocxlaer, I; Bossuyt, F; Pasmans, F

    2014-10-31

    Emerging infectious diseases are reducing biodiversity on a global scale. Recently, the emergence of the chytrid fungus Batrachochytrium salamandrivorans resulted in rapid declines in populations of European fire salamanders. Here, we screened more than 5000 amphibians from across four continents and combined experimental assessment of pathogenicity with phylogenetic methods to estimate the threat that this infection poses to amphibian diversity. Results show that B. salamandrivorans is restricted to, but highly pathogenic for, salamanders and newts (Urodela). The pathogen likely originated and remained in coexistence with a clade of salamander hosts for millions of years in Asia. As a result of globalization and lack of biosecurity, it has recently been introduced into naïve European amphibian populations, where it is currently causing biodiversity loss. PMID:25359973

  20. An orphan gene is necessary for preaxial digit formation during salamander limb development

    PubMed Central

    Kumar, Anoop; Gates, Phillip B.; Czarkwiani, Anna; Brockes, Jeremy P.

    2015-01-01

    Limb development in salamanders differs from other tetrapods in that the first digits to form are the two most anterior (preaxial dominance). This has been proposed as a salamander novelty and its mechanistic basis is unknown. Salamanders are the only adult tetrapods able to regenerate the limb, and the contribution of preaxial dominance to limb regeneration is unclear. Here we show that during early outgrowth of the limb bud, a small cohort of cells express the orphan gene Prod1 together with Bmp2, a critical player in digit condensation in amniotes. Disruption of Prod1 with a gene-editing nuclease abrogates these cells, and blocks formation of the radius and ulna, and outgrowth of the anterior digits. Preaxial dominance is a notable feature of limb regeneration in the larval newt, but this changes abruptly after metamorphosis so that the formation of anterior and posterior digits occurs together within the autopodium resembling an amniote-like pattern. PMID:26498026

  1. Heterogeneous Vesicles in Mucous Epithelial Cells of Posterior Esophagus of Chinese Giant Salamander (Andrias Davidianus)

    PubMed Central

    Zhang, H.; Zhong, S.; Ge, T.; Peng, S.; Yu, P.; Zhou, Z.; Guo, X.

    2015-01-01

    The Chinese giant salamander belongs to an old lineage of salamanders and endangered species. Many studies of breeding and disease regarding this amphibian had been implemented. However, the studies on the ultrastructure of this amphibian are rare. In this work, we provide a histological and ultra-structural investigation on posterior esophagus of Chinese giant salamander. The sections of amphibian esophagus were stained by hematoxylin & eosin (H&E). Moreover, the esophageal epithelium was observed by transmission electron microscopy (TEM). The results showed that esophageal epithelium was a single layer epithelium, which consisted of mucous cells and columnar cells. The esophageal glands were present in submucosa. The columnar cells were ciliated. According to the diverging ultrastructure of mucous vesicles, three types of mucous cells could be identified in the esophageal mucosa: i) electron-lucent vesicles mucous cell (ELV-MC); ii) electron-dense vesicles mucous cell (EDV-MC); and iii) mixed vesicles mucous cell (MV-MC). PMID:26428885

  2. Different season, different strategies: Feeding ecology of two syntopic forest-dwelling salamanders

    NASA Astrophysics Data System (ADS)

    Sebastiano, Salvidio; Antonio, Romano; Fabrizio, Oneto; Dario, Ottonello; Roberta, Michelon

    2012-08-01

    Trophic niche may be the most important ecological dimension for some vertebrate groups and in particular for terrestrial amphibians, that are important predators of soil invertebrates. In general, resource partitioning occurs between syntopic species with similar ecological niches, and coexistence patterns seem to be regulated by temporal resource variability. However most of the generalization on foraging strategies of terrestrial salamanders are extrapolated from studies on New World temperate species, thus we investigated the seasonal effect of resource variation in an European forest ecosystem, in which two ecologically similar but phylogenetically distinct salamander species are found. The diet of adult and juvenile cave salamanders (Speleomantes strinati), and of adult spectacled salamander (Salamandrina perspicillata) was obtained by stomach flushing, and results showed large seasonal changes both in prey availability and in salamander realised trophic niche. Values of trophic diversity were similar and niche overlaps were large among all salamander groups in spring, during high prey availability. Conversely in autumn, when a two-fold reduction in prey biomass was observed, there was a clear niche partitioning as the smaller S. perspicillata shifted from a generalist to a specialized trophic strategy. Juvenile Speleomantes strinatii, that largely overlapped in size with S. perspicillata, did not show any change in diet, suggesting that the feeding strategies were species-specific and not size-mediated. The observed patterns of variation in feeding ecology indicate that similar predators may react differently to changing prey availability to enhance niche partitioning. We also observed an increased energy intake during autumn for S perspicillata and S. strinatii juveniles, possibly related to differences in microhabitat use and activity patterns.

  3. Civil law problems and morbidity

    PubMed Central

    Pleasence, P; Balmer, N; Buck, A; O'Grady, A; Genn, H

    2004-01-01

    Study objective: In the United Kingdom, recognition of the links between social and health problems has led to government initiatives such as health action zones. The principles of civil law apply to many types of social problem, and the civil justice system provides one means through which they can be tackled. However, little research has been undertaken into the particular links between problems to which civil legal principles and processes can be applied and morbidity. This study examines these links, and the role of legal advice and services in preventing ill health. Design: This study examined survey respondents' self reports of longstanding illness/disability and experience of 18 problems to which legal principles can be applied. Setting: A random national survey conducted across England and Wales. Participants: 5611 adults drawn from 3348 residential households. Main results: Significant associations were found between illness/disability and 13 of the problem types. Moreover, experience of greater numbers of problems increased the likelihood of reported illness/disability. In attempting to resolve problems respondents' health also frequently suffered. Conclusions: This study highlights the contribution that public legal education and legal advice can make to the promotion of public health, and the importance of further integration of health and civil justice initiatives through health action zones, community legal service partnerships, etc, to further this end. PMID:15194714

  4. The effect of waist twisting on walking speed of an amphibious salamander like robot

    NASA Astrophysics Data System (ADS)

    Yin, Xin-Yan; Jia, Li-Chao; Wang, Chen; Xie, Guang-Ming

    2015-11-01

    Amphibious salamanders often swing their waist to coordinate quadruped walking in order to improve their crawling speed. A robot with a swing waist joint, like an amphibious salamander, is used to mimic this locomotion. A control method is designed to allow the robot to maintain the rotational speed of its legs continuous and avoid impact between its legs and the ground. An analytical expression is established between the amplitude of the waist joint and the step length. Further, an optimization amplitude is obtained corresponding to the maximum stride. The simulation results based on automatic dynamic analysis of mechanical systems (ADAMS) and physical experiments verify the rationality and validity of this expression.

  5. The effect of waist twisting on walking speed of an amphibious salamander like robot

    NASA Astrophysics Data System (ADS)

    Yin, Xin-Yan; Jia, Li-Chao; Wang, Chen; Xie, Guang-Ming

    2016-06-01

    Amphibious salamanders often swing their waist to coordinate quadruped walking in order to improve their crawling speed. A robot with a swing waist joint, like an amphibious salamander, is used to mimic this locomotion. A control method is designed to allow the robot to maintain the rotational speed of its legs continuous and avoid impact between its legs and the ground. An analytical expression is established between the amplitude of the waist joint and the step length. Further, an optimization amplitude is obtained corresponding to the maximum stride. The simulation results based on automatic dynamic analysis of mechanical systems (ADAMS) and physical experiments verify the rationality and validity of this expression.

  6. Long bone histology of the stem salamander Kokartus honorarius (Amphibia: Caudata) from the Middle Jurassic of Kyrgyzstan.

    PubMed

    Skutschas, Pavel; Stein, Koen

    2015-04-01

    Kokartus honorarius from the Middle Jurassic (Bathonian) of Kyrgyzstan is one of the oldest salamanders in the fossil record, characterized by a mixture of plesiomorphic morphological features and characters shared with crown-group salamanders. Here we present a detailed histological analysis of its long bones. The analysis of a growth series demonstrates a significant histological maturation during ontogeny, expressed by the progressive appearance of longitudinally oriented primary vascular canals, primary osteons, growth marks, remodelling features in primary bone tissues, as well as progressive resorption of the calcified cartilage, formation of endochondral bone and development of cartilaginous to bony trabeculae in the epiphyses. Apart from the presence of secondary osteons, the long bone histology of Kokartus is very similar to that of miniaturized temnospondyls, other Jurassic stem salamanders, miniaturized seymouriamorphs and modern crown-group salamanders. We propose that the presence of secondary osteons in Kokartus honorarius is a plesiomorphic feature, and the loss of secondary osteons in the long bones of crown-group salamanders as well as in those of miniaturized temnospondyls is the result of miniaturization processes. Hitherto, all stem salamander long bong histology (Kokartus, Marmorerpeton and 'salamander A') has been generally described as having paedomorphic features (i.e. the presence of Katschenko's Line and a layer of calcified cartilage), these taxa were thus most likely neotenic forms. The absence of clear lines of arrested growth and annuli in long bones of Kokartus honorarius suggests that the animals lived in an environment with stable local conditions. PMID:25682890

  7. [Contemporary work conditions and occupational morbidity in metallurgists].

    PubMed

    Chebotarev, A G; Prokhorov, V A

    2012-01-01

    Based on analysis of materials provided by Central Council of Russian Federal Coal Miners Trade Union, the authors assessed contemporary work conditions and occupational morbidity among workers engaged into iron industry. In these enterprises, a total of 68.4% of certified workplaces are assigned to hazardous and jeopardy class (3 and 4 degree of variable hazards). The article covers number of workplaces with various work condition classes in 9 metallurgy enterprises having considerable differences. The authors defined suggestions on improving activity to certify workplaces. In iron industry enterprises, level of occupational morbidity remains high (in 2010--17.85 cases per 10,000 workers examined), analysis revealed growth trend of the morbidity over 2002-2010. The morbidity materials are analysed for separate diseases, for occupational traits and among female workers. The authors defined suggestions on preventing occupational morbidity among metallurgists. PMID:22997751

  8. Molecular mechanisms of extensive mitochondrial gene rearrangementin plethodontid salamanders

    SciTech Connect

    Mueller, Rachel Lockridge; Boore, Jeffrey L.

    2005-06-01

    Extensive gene rearrangement is reported in the mitochondrial genomes of lungless salamanders (Plethodontidae). In each genome with a novel gene order, there is evidence that the rearrangement was mediated by duplication of part of the mitochondrial genome, including the presence of both pseudogenes and additional, presumably functional, copies of duplicated genes. All rearrangement-mediating duplications include either the origin of light strand replication and the nearby tRNA genes or the regions flanking the origin of heavy strand replication. The latter regions comprise nad6, trnE, cob, trnT, an intergenic spacer between trnT and trnP and, in some genomes, trnP, the control region, trnF, rrnS, trnV, rrnL, trnL1, and nad1. In some cases, two copies of duplicated genes, presumptive regulatory regions, and/or sequences with no assignable function have been retained in the genome following the initial duplication; in other genomes, only one of the duplicated copies has been retained. Both tandem and non-tandem duplications are present in these genomes, suggesting different duplication mechanisms. In some of these mtDNAs, up to 25 percent of the total length is composed of tandem duplications of non-coding sequence that includes putative regulatory regions and/or pseudogenes of tRNAs and protein-coding genes along with otherwise unassignable sequences. These data indicate that imprecise initiation and termination of replication, slipped-strand mispairing, and intra-molecular recombination may all have played a role in generating repeats during the evolutionary history of plethodontid mitochondrial genomes.

  9. A tadpole-induced polyphenism in the salamander Hynobius retardatus.

    PubMed

    Michimae, Hirofumi; Wakahara, Masami

    2002-10-01

    Larvae of the salamander Hynobius retardatus have two distinct morphs: normal and broad-headed, cannibal morphs. We performed three experiments to differentiate among the following hypotheses: The broad-headed morph is induced to allow: (1) feeding on nutritious conspecifics; (2) exclusion of strong competitors for food or space; or (3) feeding on large, tough prey when smaller prey items are unavailable. When newly hatched larvae were reared with a heterospecific, Rana pirica (an anuran amphibian) tadpoles, the broad-headed morph was induced more frequently compared with those reared with conspecifics. The phenotype expressed depended on the size of the tadpoles: The broad-headed morph occurred more frequently with small and the normal morph with large tadpoles. Metamorphosis occurred sooner in larvae fed conspecifics compared with those fed heterospecific tadpoles, and the mean growth rate of larvae fed conspecifics was significantly faster than that of those fed tadpoles, suggesting that the heterospecific tadpoles were less nutritive than the conspecifics. These results do not support the hypotheses that the broad-headed morph evolved for consuming conspecifics because of their better balance of nutrients or for excluding strong competitors for food or space. We tentatively conclude that the morph evolved to eat large, tough prey, including both conspecifics and heterospecific tadpoles. Because H. retardatus usually spawns very early in the spring in small ponds partially covered with ice and snow, newly hatched larvae may starve from the lack of proper food owing to extremely low water temperatures. Thus, the broad-headed morph of H. retardatus may represent a cold-habitat adaptation to overcome the severe circumstance when the only food items available are relatively large conspecifics or heterospecific tadpoles. PMID:12449490

  10. Incipient species formation in salamanders of the Ensatina complex

    PubMed Central

    Wake, David B.

    1997-01-01

    The Ensatina eschscholtzii complex of plethodontid salamanders, a well-known “ring species,” is thought to illustrate stages in the speciation process. Early research, based on morphology and coloration, has been extended by the incorporation of studies of protein variation and mitochondrial DNA sequences. The new data show that the complex includes a number of geographically and genetically distinct components that are at or near the species level. The complex is old and apparently has undergone instances of range contraction, isolation, differentiation, and then expansion and secondary contact. While the hypothesis that speciation is retarded by gene flow around the ring is not supported by molecular data, the general biogeographical hypothesis is supported. There is evidence of a north to south range expansion along two axes, with secondary contact and completion of the ring in southern California. Current research targets regions once thought to show primary intergradation, but which molecular markers reveal to be zones of secondary contact. Here emphasis is on the subspecies E. e. xanthoptica, which is involved in four distinct secondary contacts in central California. There is evidence of renewed genetic interactions upon recontact, with greater genetic differentiation within xanthoptica than between it and some of the interacting populations. The complex presents a full array of intermediate conditions between well-marked species and geographically variable populations. Geographically differentiated segments represent a diversity of depths of time of isolation and admixture, reflecting the complicated geomorphological history of California. Ensatina illustrates the continuing difficulty in making taxonomic assignments in complexes studied during species formation. PMID:9223261

  11. Treatment of Morbidity with Atypical Chest Pain

    PubMed Central

    Cott, Arthur

    1987-01-01

    The appropriate management of atypical chest pain requires an integration of medical and behavioural treatments. Unnecessary medicalization can increase morbidity. A sensitivity to the behavioural factors contributing to symptoms and disability may reduce both. The purpose of this paper is to provide physicians with a cognitive-behavioural perspective of the nature of morbidity and disability associated with chronic chest discomfort; some strategies for detecting heretofore unsuspected disability associated with chronic chest pain and related discomfort in patients with organic findings (both cardiac and non-cardiac), as well those with no identifiable disease process or organic cause; and some simple behavioural and cognitive-behavioural therapeutic techniques for treating and preventing such problems. PMID:21263912

  12. Effect of acute low body temperature on predatory behavior and prey-capture efficiency in a plethodontid salamander.

    PubMed

    Marvin, Glenn A; Davis, Kayla; Dawson, Jacob

    2016-05-01

    The low-temperature limit for feeding in some salamander species (Desmognathus, Plethodontidae) has been inferred from field studies of seasonal variation in salamander activity and gut contents, which could not determine whether feeding is more dependent on environmental conditions influencing salamander foraging behavior or prey availability and movement. We performed two controlled laboratory experiments to examine the effect of short-term (acute) low body temperature on predatory behavior and prey-capture efficiency in a semiaquatic plethodontid salamander (Desmognathus conanti). In the first experiment, we quantified variation in the feeding responses of cold salamanders (at 1, 3, 5 and 7°C) to a video recording of a walking, warm (15°C) cricket to determine the lower thermal limit for predatory behavior, independent of any temperature effect on movement of prey. Experimental-group salamanders exhibited vigorous feeding responses at 5 and 7°C, large variation in feeding responses both among and within individuals (over time) at 3°C, and little to no feeding response at 1°C. Feeding responses at both 1 and 3°C were significantly less than at each higher temperature, whereas responses of control-group individuals at 15°C did not vary over time. In the second experiment, we quantified feeding by cold salamanders (at 3, 5, 7 and 11°C) on live, warm crickets to examine thermal effects on prey-capture ability. The mean feeding response to live crickets was significantly less at 3°C than at higher temperatures; however, 50% of salamanders captured and ingested prey with high efficiency at this temperature. We conclude that many individuals stalk and capture prey at very low temperatures (down to 3°C). Our results support a growing body of data that indicate many plethodontid salamanders feed at temperatures only a few degrees above freezing. PMID:26939728

  13. Near infrared reflectance spectroscopy studies of Chinese giant salamanders in aquaculture production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NIR spectra were collected at three surface locations for Chinese giant salamanders to ascertain whether spectral signatures could be separated by anatomical, presumably physiologically-based, locations. The first location was the smooth area immediately above the cloaca on the animal’s abdomen, whi...

  14. Survival of spotted salamander eggs in temporary woodland ponds of coastal Maryland

    USGS Publications Warehouse

    Albers, P.H.; Prouty, R.M.

    1987-01-01

    Temporary ponds on the Atlantic Coastal Plain in maryland were characterized according to water chemistry, rain input, phytoplankton, zooplankton and use by the spotted salamander Ambystoma maculatum during March-October 1983-1984. Neither the number of egg masses per unit of pond surface (abundance) nor the survival of spotted salamander embryos was significantly correlated (P>0.05) with pond pH. Rainfall during May-July significantly increased the hydrogen ion concentration of 5 of 11 ponds evaluated for the impact of rainfall during the previous 48h and the previous week. Survival of egg masses transferred among eight ponds with pH3.66-4.45 and one pond with pH5.18 was significantly reduced (Psalamander. At the present time, pond longevity, water temperature and possibly, oxygen content, seem more important to spotted salamander reproduction than chemical changes caused by annual acidic deposition.

  15. Using the Eastern Hellbender Salamander in a High School Genetics & Ecological Conservation Activity

    ERIC Educational Resources Information Center

    Chudyk, Sarah; McMillan, Amy; Lange, Catherine

    2014-01-01

    This article contains an original 5E lesson plan developed from conservation genetics research on the giant North American hellbender salamander, Cryptobranchus alleganiensis alleganiensis. The lesson plan provides background information on the hellbender, reviews basic genetics, and exposes students to the scientific process that is used during…

  16. A survey for Batrachochytrium dendrobatidis in endangered and highly susceptible Vietnamese salamanders (Tylototriton spp.).

    PubMed

    Thien, Tao Nguyen; Martel, An; Brutyn, Melanie; Bogaerts, Sergé; Sparreboom, Max; Haesebrouck, Freddy; Fisher, Matthew C; Beukema, Wouter; Van, Tang Duong; Chiers, Koen; Pasmans, Frank

    2013-09-01

    Until now, Asian amphibians appear to have largely escaped declines driven by chytridiomycosis. Vietnamese salamanders that belong to the genus Tylototriton are rare and have a patchy distribution in mountainous areas, falling within the proposed environmental envelope of chytrid infections, surrounded by Batrachochytrium dendrobatidis infected regions. If these salamanders are susceptible to chytridiomycosis, then their populations could be highly vulnerable after the introduction of B. dendrobatidis. Examination for the presence of the chytrid fungus in skin swabs from 19 Tylototriton asperrimus and 104 Tylototriton vietnamensis by using quantitative polymerase chain reaction was performed. Susceptibility of T. asperrimus to experimental infection by using the global panzootic lineage (BdGPL) strain of B. dendrobatidis was examined. The fungus was absent in all samples from all wild salamanders examined. Inoculation with the BdGPL strain resulted in mortality of all five inoculated salamanders within 3 weeks after inoculation with infected animals that manifested severe orthokeratotic hyperkeratosis, epidermal hyperplasia, and spongiosis. Although infection by B. dendrobatidis currently appears absent in Vietnamese Tylototriton populations, the rarity of these animals, their pronounced susceptibility to chytridiomycosis, an apparently suitable environmental context and increasing likelihood of the pathogen being introduced, together suggest the need of urgent measures to avoid future scenarios of extinction as witnessed in Central America and Australia. PMID:24063090

  17. Stream salamander species richness and abundance in relation to environmental factors in Shenandoah National Park, Virginia

    USGS Publications Warehouse

    Grant, E.H.C.; Jung, R.E.; Rice, K.C.

    2005-01-01

    Stream salamanders are sensitive to acid mine drainage and may be sensitive to acidification and low acid neutralizing capacity (ANC) of a watershed. Streams in Shenandoah National Park, Virginia, are subject to episodic acidification from precipitation events. We surveyed 25 m by 2 m transects located on the stream bank adjacent to the water channel in Shenandoah National Park for salamanders using a stratified random sampling design based on elevation, aspect and bedrock geology. We investigated the relationships of four species (Eurycea bislineata, Desmognathus fuscus, D. monticola and Gyrinophilus porphyriticus) to habitat and water quality variables. We did not find overwhelming evidence that stream salamanders are affected by the acid-base status of streams in Shenandoah National Park. Desmognathus fuscus and D. monticola abundance was greater both in streams that had a higher potential to neutralize acidification, and in higher elevation (>700 m) streams. Neither abundance of E. bislineata nor species richness were related to any of the habitat variables. Our sampling method preferentially detected the adult age class of the study species and did not allow us to estimate population sizes. We suggest that continued monitoring of stream salamander populations in SNP will determine the effects of stream acidification on these taxa.

  18. Sal-Site: Integrating new and existing ambystomatid salamander research and informational resources

    PubMed Central

    Smith, Jeramiah J; Putta, Srikrishna; Walker, John A; Kump, D Kevin; Samuels, Amy K; Monaghan, James R; Weisrock, David W; Staben, Chuck; Voss, S Randal

    2005-01-01

    Salamanders of the genus Ambystoma are a unique model organism system because they enable natural history and biomedical research in the laboratory or field. We developed Sal-Site to integrate new and existing ambystomatid salamander research resources in support of this model system. Sal-Site hosts six important resources: 1) Salamander Genome Project: an information-based web-site describing progress in genome resource development, 2) Ambystoma EST Database: a database of manually edited and analyzed contigs assembled from ESTs that were collected from A. tigrinum tigrinum and A. mexicanum, 3) Ambystoma Gene Collection: a database containing full-length protein-coding sequences, 4) Ambystoma Map and Marker Collection: an image and database resource that shows the location of mapped markers on linkage groups, provides information about markers, and provides integrating links to Ambystoma EST Database and Ambystoma Gene Collection databases, 5) Ambystoma Genetic Stock Center: a website and collection of databases that describe an NSF funded salamander rearing facility that generates and distributes biological materials to researchers and educators throughout the world, and 6) Ambystoma Research Coordination Network: a web-site detailing current research projects and activities involving an international group of researchers. Sal-Site is accessible at . PMID:16359543

  19. Cytogenetics of the Brazilian Bolitoglossa paraensis (Unterstein, 1930) salamanders (Caudata, Plethodontidae)

    PubMed Central

    da Silva, Jéssica Barata; Suárez, Pablo; Nagamachi, Cleusa Yoshiko; Carter, Timothy Frederick; Pieczarka, Julio Cesar

    2014-01-01

    Plethodontid salamanders of genus Bolitoglossa constitute the largest and most diverse group of salamanders, including around 20% of living caudate species. Recent studies have indicated the occurrence of five recognized species in the Brazilian Amazon Rainforest. We present here the first cytogenetic data of a Brazilian salamander, which may prove to be a useful by contribution to the cytotaxonomy of the genus. Specimens were collected near the “type” locality (Utinga, Belém, PA, Brazil). Chromosomal preparations from duodenal epithelial cells and testes were subjected to Giemsa staining, C-banding and DAPI/CMA3 fluorochrome staining. All specimens showed a karyotype with 13 bi-armed chromosome pairs (2n = 26). Nucleolar Organizer Regions, evidenced by CMA3, were located distally on the long arm of pair 7 (7q). DAPI+ heterochromatin was predominantly centromeric, with some small pericentromeric bands. Although the C-banding patterns of other Bolitoglossa species are so far unknown, cytogenetic studies conducted in other Plethodontid salamanders have demonstrated that pericentromeric heterochromatin is a useful cytological marker for identifying interspecific homeologies. Species diversification is usually accompanied by chromosomal changes. Therefore, the cytogenetic characterization of Bolitoglossa populations from the middle and western Brazilian Amazon Basin could identify differences which may lead to the identification of new species. PMID:25249775

  20. Cytogenetics of the Brazilian Bolitoglossa paraensis (Unterstein, 1930) salamanders (Caudata, Plethodontidae).

    PubMed

    da Silva, Jéssica Barata; Suárez, Pablo; Nagamachi, Cleusa Yoshiko; Carter, Timothy Frederick; Pieczarka, Julio Cesar

    2014-09-01

    Plethodontid salamanders of genus Bolitoglossa constitute the largest and most diverse group of salamanders, including around 20% of living caudate species. Recent studies have indicated the occurrence of five recognized species in the Brazilian Amazon Rainforest. We present here the first cytogenetic data of a Brazilian salamander, which may prove to be a useful by contribution to the cytotaxonomy of the genus. Specimens were collected near the "type" locality (Utinga, Belém, PA, Brazil). Chromosomal preparations from duodenal epithelial cells and testes were subjected to Giemsa staining, C-banding and DAPI/CMA3 fluorochrome staining. All specimens showed a karyotype with 13 bi-armed chromosome pairs (2n = 26). Nucleolar Organizer Regions, evidenced by CMA3, were located distally on the long arm of pair 7 (7q). DAPI+ heterochromatin was predominantly centromeric, with some small pericentromeric bands. Although the C-banding patterns of other Bolitoglossa species are so far unknown, cytogenetic studies conducted in other Plethodontid salamanders have demonstrated that pericentromeric heterochromatin is a useful cytological marker for identifying interspecific homeologies. Species diversification is usually accompanied by chromosomal changes. Therefore, the cytogenetic characterization of Bolitoglossa populations from the middle and western Brazilian Amazon Basin could identify differences which may lead to the identification of new species. PMID:25249775

  1. Transcriptomic analysis of the host response to an iridovirus infection in Chinese giant salamander, Andrias davidianus.

    PubMed

    Fan, Yuding; Chang, Ming Xian; Ma, Jie; LaPatra, Scott E; Hu, Yi Wei; Huang, Lili; Nie, Pin; Zeng, Lingbing

    2015-01-01

    The emergence of an infectious viral disease caused by the Chinese giant salamander iridovirus (GSIV) has led to substantial economic losses. However, no more molecular information is available for the understanding of the mechanisms associated with virus-host interaction. In this study, de novo sequencing was used to obtain abundant high-quality ESTs and investigate differentially-expressed genes in the spleen of Chinese giant salamanders that were either infected or mock infected with GSIV. Comparative expression analysis indicated that 293 genes were down-regulated and 220 genes were up-regulated. Further enrichment analysis showed that the most enriched pathway is "complement and coagulation cascades", and significantly enriched diseases include "inherited thrombophilia", "immune system diseases", "primary immunodeficiency", "complement regulatory protein defects", and "disorders of nucleotide excision repair". Additionally, 30 678 simple sequence repeats (SSRs) from all spleen samples, 26 355 single nucleotide polymorphisms (SNPs) from the spleens of uninfected animals and 36 070 SNPs from the spleens of infected animals were detected. The large amount of variation was specific for the Chinese giant salamanders that were infected with GSIV. The results reported herein provided significant and new EST information that could contribute greatly in investigations into the molecular functions of immune genes in the Chinese giant salamander. PMID:26589400

  2. Lagged influence of North Atlantic Oscillation on population dynamics of a Mediterranean terrestrial salamander

    NASA Astrophysics Data System (ADS)

    Salvidio, Sebastiano; Oneto, Fabrizio; Ottonello, Dario; Pastorino, Mauro V.

    2016-04-01

    The North Atlantic Oscillation (NAO) is a large-scale climatic pattern that strongly influences the atmospheric circulation in the northern Hemisphere and by consequence the long-term variability of marine and terrestrial ecosystem over great part of northern Europe and western Mediterranean. In the Mediterranean, the effects of the NAO on vertebrates has been studied mainly on bird populations but was rarely analysed in ectothermic animals, and in particular in amphibians. In this study, we investigated the relationships between winter, spring and summer NAO indexes and the long-term population dynamics of the plethodontid salamander Speleomantes strinatii. This terrestrial salamander was monitored inside an artificial cave in NW Italy for 24 consecutive years. The relationships between seasonal NAO indexes and the salamander dynamics were assessed by cross-correlation function (CCF) analysis, after prewhitening the time series by autoregressive moving average statistical modelling. Results of CCF analyses indicated that the salamander abundance varied in relation to the one-year ahead winter NAO ( P = 0.018), while no relationships were found with spring and summer indexes. These results strengthen some previous findings that suggested a high sensitivity of temperate terrestrial amphibians to wintertime climatic conditions.

  3. The Amphibian Chytrid Fungus, Batrachochytrium dendrobatidis, in Fully Aquatic Salamanders from Southeastern North America

    PubMed Central

    Chatfield, Matthew W. H.; Moler, Paul; Richards-Zawacki, Corinne L.

    2012-01-01

    Little is known about the impact that the pathogenic amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), has on fully aquatic salamander species of the eastern United States. As a first step in determining the impacts of Bd on these species, we aimed to determine the prevalence of Bd in wild populations of fully aquatic salamanders in the genera Amphiuma, Necturus, Pseudobranchus, and Siren. We sampled a total of 98 salamanders, representing nine species from sites in Florida, Mississippi, and Louisiana. Overall, infection prevalence was found to be 0.34, with significant differences among genera but no clear geographic pattern. We also found evidence for seasonal variation, but additional sampling throughout the year is needed to clarify this pattern. The high rate of infection discovered in this study is consistent with studies of other amphibians from the southeastern United States. Coupled with previously published data on life histories and population densities, the results presented here suggest that fully aquatic salamanders may be serving as important vectors of Bd and the interaction between these species and Bd warrants additional research. PMID:22984569

  4. Lagged influence of North Atlantic Oscillation on population dynamics of a Mediterranean terrestrial salamander.

    PubMed

    Salvidio, Sebastiano; Oneto, Fabrizio; Ottonello, Dario; Pastorino, Mauro V

    2016-04-01

    The North Atlantic Oscillation (NAO) is a large-scale climatic pattern that strongly influences the atmospheric circulation in the northern Hemisphere and by consequence the long-term variability of marine and terrestrial ecosystem over great part of northern Europe and western Mediterranean. In the Mediterranean, the effects of the NAO on vertebrates has been studied mainly on bird populations but was rarely analysed in ectothermic animals, and in particular in amphibians. In this study, we investigated the relationships between winter, spring and summer NAO indexes and the long-term population dynamics of the plethodontid salamander Speleomantes strinatii. This terrestrial salamander was monitored inside an artificial cave in NW Italy for 24 consecutive years. The relationships between seasonal NAO indexes and the salamander dynamics were assessed by cross-correlation function (CCF) analysis, after prewhitening the time series by autoregressive moving average statistical modelling. Results of CCF analyses indicated that the salamander abundance varied in relation to the one-year ahead winter NAO (P = 0.018), while no relationships were found with spring and summer indexes. These results strengthen some previous findings that suggested a high sensitivity of temperate terrestrial amphibians to wintertime climatic conditions. PMID:26160231

  5. Phylogeographic concordance in the southeastern United States: the flatwoods salamander, Ambystoma cingulatum, as a test case.

    PubMed

    Pauly, Gregory B; Piskurek, Oliver; Shaffer, H Bradley

    2007-01-01

    Well-supported, congruent phylogeographic and biogeographic patterns permit the development of a priori phylogeographic and distributional predictions. In the southeastern Coastal Plain of the United States, the common discovery of east-west disjunctions (phylogeographic breaks and species' distributional boundaries) suggests that similar disjunctions should occur in codistributed taxa. Despite the near ubiquity of these disjunctions, the most recent morphological analyses of the flatwoods salamander, Ambystoma cingulatum, indicate that none occur in this low-vagility, Coastal Plain endemic. We conducted molecular and morphological analyses to test whether the flatwoods salamander is an exception to this common biogeographic pattern. Assessing geographic variation in this species is also an important management tool for this threatened, declining amphibian. We demonstrate that flatwoods salamanders, as predicted by comparisons to codistributed taxa, are polytypic with a major disjunction at the Apalachicola River. This drainage is a common site for east-west phylogeographic breaks, probably because repeated marine embayments during the Pliocene and Pleistocene interglacials generated barriers to gene flow. Based on mitochondrial DNA, morphology, and allozymes, we recognize two species of flatwoods salamanders -- Ambystoma cingulatum to the east of the Apalachicola drainage and Ambystoma bishopi to the west. Given this increased diversity, the conservation status of these two taxa may warrant re-evaluation. More generally, these results emphasize that in the absence of taxon-specific data, established comparative patterns can provide strong expectations for designing management units for unstudied species of conservation concern. PMID:17217354

  6. A stem batrachian from the Early Permian of Texas and the origin of frogs and salamanders.

    PubMed

    Anderson, Jason S; Reisz, Robert R; Scott, Diane; Fröbisch, Nadia B; Sumida, Stuart S

    2008-05-22

    The origin of extant amphibians (Lissamphibia: frogs, salamanders and caecilians) is one of the most controversial questions in vertebrate evolution, owing to large morphological and temporal gaps in the fossil record. Current discussions focus on three competing hypotheses: a monophyletic origin within either Temnospondyli or Lepospondyli, or a polyphyletic origin with frogs and salamanders arising among temnospondyls and caecilians among the lepospondyls. Recent molecular analyses are also controversial, with estimations for the batrachian (frog-salamander) divergence significantly older than the palaeontological evidence supports. Here we report the discovery of an amphibamid temnospondyl from the Early Permian of Texas that bridges the gap between other Palaeozoic amphibians and the earliest known salientians and caudatans from the Mesozoic. The presence of a mosaic of salientian and caudatan characters in this small fossil makes it a key taxon close to the batrachian (frog and salamander) divergence. Phylogenetic analysis suggests that the batrachian divergence occurred in the Middle Permian, rather than the late Carboniferous as recently estimated using molecular clocks, but the divergence with caecilians corresponds to the deep split between temnospondyls and lepospondyls, which is congruent with the molecular estimates. PMID:18497824

  7. Vertebral development of modern salamanders provides insights into a unique event of their evolutionary history.

    PubMed

    Boisvert, Catherine Anne

    2009-01-15

    The origin of salamanders and their interrelationships to the two other modern amphibian orders (frogs and caecilians) are problematic owing to an 80-100 million year gap in the fossil record between the Carboniferous to the Lower Jurassic. This is compounded by a scarcity of adult skeletal characters linking the early representatives of the modern orders to their stem-group in the Paleozoic. The use of ontogenetic characters can be of great use in the resolution of these questions. Growth series of all ten modern salamander families (a 120 cleared and stained larvae) were examined for pattern and timing of vertebral elements chondrification and ossification. The primitive pattern is that of the neural arches developing before the centra, while the reverse represents the derived condition. Both the primitive and derived conditions are observed within the family Hynobiidae, whereas only the derived condition is observed in all other salamanders. This provides support to the claims that Hynobiidae is both the most basal of modern families and potentially polyphyletic (with Ranodon and Hybobius forming the most basal clade and Salamandrella being a part of the most derived clade). This provides insight into a unique event in salamander evolutionary history and suggests that the developmental pattern switch occurred between the Triassic and the mid-Jurassic before the last major radiation. PMID:19025964

  8. At random meetings to the creation of new species of Salamander

    NASA Astrophysics Data System (ADS)

    Brillant, Marie-Pierre

    2013-04-01

    The pupils in final year of high school (15-18 years old) study the notion "species" and the creation of new species in various ways. Having studied genetic admixtures, this activity allows the pupils to build a scenario explaining the creation of a new species of Salamander in southern California from an ancestral population existing in northern Oregon. They can observe, on Google Earth, various populations of Salamander of the genus Ensatina. Salamanders of the genus Ensatina live in California around the Joaquin and Sacramento dry valleys. In this software, the pupils get information about the salamanders' environment and photographs of individuals and environments. During a migratory movement toward new territories to be colonized, these salamanders meet an inhospitable environment that they can not occupy. This population then splits up into two migratory branches, east and west, each overcoming the obstacles in different ways. The two groups gradually colonized southern territories but they avoided the too dry and hot San Joaquin plains. The two main branches of the original population gradually move away from each other, and genetic exchanges between them decrease over time. Eventually, we can find various populations of Salamander on both sides of the valleys, since the salamanders occupied new territories and diversified along the way. Among mutations that randomly occur, only those mutations that are best adapted in the origin were conserved in the genetic heritage of every population. When the individuals stemming from different western populations met, they were interfertile and give fertile hybrids, which was verified in the laboratory. Likewise, when individuals of the different eastern subspecies met accidentally, fertile hybrids also could arise from these crossings. The pupils can observe what happens in the overlap of various populations : interfertility or not. They also have geological, geographical and climatic information about the San Joaquin

  9. Evaluating multi-level models to test occupancy state responses of Plethodontid salamanders

    USGS Publications Warehouse

    Kroll, Andrew J.; Garcia, Tiffany S.; Jones, Jay E.; Dugger, Catherine; Murden, Blake; Johnson, Josh; Peerman, Summer; Brintz, Ben; Rochelle, Michael

    2015-01-01

    Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology and responses to conservation and management activities. We conducted a simulation study to evaluate the effectiveness of multi-scale and hierarchical single-scale occupancy models in the context of a Before-After Control-Impact (BACI) experimental design with multiple levels of sampling. Also, we fit the hierarchical single-scale model to empirical data collected for Oregon slender and Ensatina salamanders across two years on 66 forest stands in the Cascade Range, Oregon, USA. All models were fit within a Bayesian framework. Estimator precision in both models improved with increasing numbers of primary and secondary sampling units, underscoring the potential gains accrued when adding secondary sampling units. Both models showed evidence of estimator bias at low detection probabilities and low sample sizes; this problem was particularly acute for the multi-scale model. Our results suggested that sufficient sample sizes at both the primary and secondary sampling levels could ameliorate this issue. Empirical data indicated Oregon slender salamander occupancy was associated strongly with the amount of coarse woody debris (posterior mean = 0.74; SD = 0.24); Ensatina occupancy was not associated with amount of coarse woody debris (posterior mean = -0.01; SD = 0.29). Our simulation results indicate that either model is suitable for use in an experimental study of Plethodontid salamanders provided that sample sizes are sufficiently large. However, hierarchical single-scale and multi-scale models describe different processes and estimate different parameters. As a result, we recommend careful consideration of study questions

  10. Mercury Speciation and Trophic Magnification Slopes in Giant Salamander Larvae from the Pacific Northwest, USA

    NASA Astrophysics Data System (ADS)

    Bank, M. S.; Crocker, J.; Wachtl, J.; Kleeman, P.; Fellers, G.; Currens, C.; Hothem, R.; Madej, M. A.

    2014-12-01

    Mercury (Hg) contamination of stream salamanders in the Pacific Northwest region of the United States has received little attention. Here we report total Hg (HgT) and methyl mercury (MeHg) concentrations in larval giant salamanders (Dicamptodon spp.) and surface water from forested and chaparral lotic ecosystems distributed along a latitudinal gradient throughout Northern California and Washington. To test hypotheses related to potential effects from mining land-use activities, salamander larvae were also sampled from a reference site at Whiskeytown National Recreation Area, California, and at a nearby, upstream site (Shasta county) on Bureau of Land Management land where Hg contamination from gold mining activities has been documented. HgT concentrations in whole body larvae ranged from 4.6 to 74.5 ng/g wet wt. and percent MeHg ranged from 67% to 86%. Both HgT and MeHg larval tissue concentrations were significantly higher at the mining site in comparison to measured background levels (P < 0.001). We conclude that salamander larvae in remote stream ecosystems, where Hg sources were dominated by atmospheric deposition, were generally low in HgT and MeHg and, in comparison, watersheds with a legacy of land-use practices (i.e., mining operations) had approximately 4.5 - 5.5 times the level of HgT bioaccumulation. Moreover, trophic magnification slopes were highest in the Shasta county region where mining was present. These findings suggest that mining activities increase HgT and MeHg exposure to salamander larvae in the region and may present a threat to other higher trophically positioned organisms, and their associated food webs.

  11. Three ferritin subunit analogs in Chinese giant salamander (Andrias davidianus) and their response to microbial stimulation.

    PubMed

    You, Xiuling; Sheng, Jianghong; Liu, Liu; Nie, Dongsong; Liao, Zhiyong

    2015-10-01

    Ferritin, an evolutionarily conserved iron-binding protein, plays important roles in iron storage and detoxification and in host immune response to invading stimulus as well. In the present study, we identified three ferritin subunit analog cDNAs from Chinese giant salamander (Andrias davidianus). All the three ferritin subunit cDNAs had a putative iron responsive element in the 5'-untranslated region. Two deduced ferritin subunits (designated as cgsFerH and cgsFerM) had the highest identity of 90% to H type subunit of vertebrate ferritins, while another deduced ferritin subunit (designated as cgsFerL) had the highest identity of 84% to L type subunit of vertebrate ferritins. The Chinese giant salamander ferritin (cgsFer) was widely expressed in various tissues, with highest expression for cgsFerH and cgsFerL in liver and highest expression for cgsFerM in spleen. Infection of Chinese giant salamander with A. davidianus ranavirus showed significant induction of cgsFer expression. Both lipopolysaccharide and iron challenge drastically augmented cgsFer expression in the splenocytes and hepatocytes from Chinese giant salamander. In addition, recombinant cgsFers bound to ferrous iron in a dose-dependent manner, with significant ferroxidase activity. Furthermore, the recombinant cgsFer inhibited the growth of the pathogen Vibrio anguillarum. These results indicated that cgsFer was potential candidate of immune molecules involved in acute phase response to invading microbial pathogens in Chinese giant salamander possibly through its regulatory roles in iron homeostasis. PMID:26319314

  12. Evaluating Multi-Level Models to Test Occupancy State Responses of Plethodontid Salamanders

    PubMed Central

    Kroll, Andrew J.; Garcia, Tiffany S.; Jones, Jay E.; Dugger, Katie; Murden, Blake; Johnson, Josh; Peerman, Summer; Brintz, Ben; Rochelle, Michael

    2015-01-01

    Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology and responses to conservation and management activities. We conducted a simulation study to evaluate the effectiveness of multi-scale and hierarchical single-scale occupancy models in the context of a Before-After Control-Impact (BACI) experimental design with multiple levels of sampling. Also, we fit the hierarchical single-scale model to empirical data collected for Oregon slender and Ensatina salamanders across two years on 66 forest stands in the Cascade Range, Oregon, USA. All models were fit within a Bayesian framework. Estimator precision in both models improved with increasing numbers of primary and secondary sampling units, underscoring the potential gains accrued when adding secondary sampling units. Both models showed evidence of estimator bias at low detection probabilities and low sample sizes; this problem was particularly acute for the multi-scale model. Our results suggested that sufficient sample sizes at both the primary and secondary sampling levels could ameliorate this issue. Empirical data indicated Oregon slender salamander occupancy was associated strongly with the amount of coarse woody debris (posterior mean = 0.74; SD = 0.24); Ensatina occupancy was not associated with amount of coarse woody debris (posterior mean = -0.01; SD = 0.29). Our simulation results indicate that either model is suitable for use in an experimental study of Plethodontid salamanders provided that sample sizes are sufficiently large. However, hierarchical single-scale and multi-scale models describe different processes and estimate different parameters. As a result, we recommend careful consideration of study questions

  13. The hyal and ventral branchial muscles in caecilian and salamander larvae: homologies and evolution.

    PubMed

    Kleinteich, Thomas; Haas, Alexander

    2011-05-01

    Amphibians (Lissamphibia) are characterized by a bi-phasic life-cycle that comprises an aquatic larval stage and metamorphosis to the adult. The ancestral aquatic feeding behavior of amphibian larvae is suction feeding. The negative pressure that is needed for ingestion of prey is created by depression of the hyobranchial apparatus as a result of hyobranchial muscle action. Understanding the homologies of hyobranchial muscles in amphibian larvae is a crucial step in understanding the evolution of this important character complex. However, the literature mostly focuses on the adult musculature and terms used for hyal and ventral branchial muscles in different amphibians often do not reflect homologies across lissamphibian orders. Here we describe the hyal and ventral branchial musculature in larvae of caecilians (Gymnophiona) and salamanders (Caudata), including juveniles of two permanently aquatic salamander species. Based on previous alternative terminology schemes, we propose a terminology for the hyal and ventral branchial muscles that reflects the homologies of muscles and that is suited for studies on hyobranchial muscle evolution in amphibians. We present a discussion of the hyal and ventral branchial muscles in larvae of the most recent common ancestor of amphibians (i.e. the ground plan of Lissamphibia). Based on our terminology, the hyal and ventral branchial musculature of caecilians and salamanders comprises the following muscles: m. depressor mandibulae, m. depressor mandibulae posterior, m. hyomandibularis, m. branchiohyoideus externus, m. interhyoideus, m. interhyoideus posterior, m. subarcualis rectus I, m. subarcualis obliquus II, m. subarcualis obliquus III, m. subarcualis rectus II-IV, and m. transversus ventralis IV. Except for the m. branchiohyoideus externus, all muscles considered herein can be assigned to the ground plan of the Lissamphibia with certainty. The m. branchiohyoideus externus is either apomorphic for the Batrachia (frogs

  14. Socioeconomic Status, Migration, and Morbidity

    ERIC Educational Resources Information Center

    Wan, Thomas T. H.; Tarver, James D

    1972-01-01

    The conceptual framework of this study is that various population groups have different vulnerabilities to disease, and that different levels of social psychological stress induced by different social stressors lead to differential rates of morbidity. (DM)

  15. Morbidity of severe obesity.

    PubMed

    Kral, J G

    2001-10-01

    Although obesity is an easy diagnosis to make, its etiologies, pathophysiology, and symptomatology are extraordinarily complex. Progress in surgical technique and anesthesiological management has substantially improved the safety of performing operations on the severely obese in the last 20 years. These improvements have occurred more or less empirically, without a full understanding of etiology or pathophysiology, although this has advanced concomitantly with improvements in practice. This review has attempted to provide a framework to facilitate progress in the neglected areas of patient selection and choice of operation, in an effort to improve long-term outcome. Despite the disparate etiologies of obesity and its diverse comorbidities and complications, there are unifying interdependent pathogenetic mechanisms of great relevance to the practice of antiobesity surgery. The rate of eating, whether driven by HPA dysfunction, ambient stress, or related hereditary susceptibility factors including the increased energy demands of an expanded body fat mass, participates in a cycle that results in disordered satiety (see Fig. 3). This leads to substrate overload, causing extensive metabolic abnormalities such as atherogenesis, insulin resistance, thrombogenesis, and carcinogenesis. This interpretation of the pathophysiology of obesity ironically accords with the original meaning of the word obesity: "to overeat." The ultimate solution to the problem of obesity--preventing it--will not be forthcoming until the food industry is forced to lower production and change its marketing strategies, as the liquor and tobacco industries in the United States were compelled to do. This cannot occur until the large and fast-growing populations of industrialized nations become educated in the personal implications of the energy principle. Regardless of whether school curricula are modified to prioritize health education, the larger problems of cultural and economic change remain for

  16. Phylogeography and evolution of the Red Salamander (Pseudotriton ruber).

    PubMed

    Folt, Brian; Garrison, Nicole; Guyer, Craig; Rodriguez, Juanita; Bond, Jason E

    2016-05-01

    Phylogeographic studies frequently result in the elevation of subspecific taxa to species given monophyly, or the synonymy of subspecies that are not monophyletic. However, given limited or incongruent datasets, retention of subspecies can be useful to describe hypothesized incipient species or to illustrate interesting biological phenomena driving morphological diversity. Four subspecific taxa have been used to describe largely allopatric geographic variation within the species Pseudotriton ruber, a plethodontid salamander occupying stream and spring habitats across eastern North America: P. r. vioscai occurs in lowland Coastal Plain habitats, while P. r. ruber, P. r. nitidus, and P. r. schencki occupy upland regions in and around the Appalachian Mountains. Pseudotriton ruber co-occurs through its distribution with the aposematic newt Notophthalmus viridescens, and both species are hypothesized to be part of a Müllerian mimicry complex. In this study, we sequenced regions of two mitochondrial (cytochrome b, NADH dehydrogenase subunit 2) and one single copy nuclear protein-coding gene (pro-opiomelanocortin) from individuals sampled across much of the distribution of P. ruber and then used maximum-likelihood and Bayesian phylogenetic inference to test the monophyly of subspecies, reconstruct biogeographic history, and make inferences about morphological evolution. Phylogeographic hypotheses from mitochondrial and nuclear datasets described structure among populations of P. ruber which separated Coastal Plain and upland Appalachian populations, but subspecies were not monophyletic. Biogeographic reconstruction estimated the ancestor of all populations to have occupied and initially diverged in the Coastal Plain during the Pliocene (∼3.6mya), before one lineage subsequently invaded upland areas of Appalachia. Bold bright coloration of high elevation subspecies P. r. nitidus and P. r. schencki appears to have evolved twice. We hypothesize that the Müllerian mimicry

  17. Impacts of a gape limited Brook Trout, Salvelinus fontinalis, on larval Northwestern salamander, Ambystoma gracile, growth: A field enclosure experiment

    USGS Publications Warehouse

    Currens, C.R.; Liss, W.J.; Hoffman, R.L.

    2007-01-01

    The formation of amphibian population structure is directly affected by predation. Although aquatic predators have been shown to have direct negative effects on larval salamanders in laboratory and field experiments, the potential impacts of gape-limited fish on larval salamander growth has been largely underexplored. We designed an enclosure experiment conducted in situ to quantify the effects of gape-limited Brook Trout (Salvelinus fontinalis) on larval Northwestern Salamander (Ambystoma gracile) growth. We specifically tested whether the presence of fish too small to consume larvae had a negative effect on larval growth. The results of this study indicate that the presence of a gape-limited S. fontinalis can have a negative effect on growth of larval A. gracile salamanders. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  18. Morbidity and Mortality in Sarcoidosis

    PubMed Central

    Gerke, Alicia K.

    2015-01-01

    Purpose of Review Chronic sarcoidosis is a complex disease with numerous comorbid conditions and can be fatal in some cases. Recognizing causes of morbidity and mortality is important to effectively select treatments, manage symptoms, and improve outcomes. The purpose of this review is to examine emerging knowledge on morbidity and mortality in sarcoidosis. Recent Findings Approximately one to five percent of patients with sarcoidosis die from complications of sarcoidosis. Recent population studies indicate that mortality may be increasing over the past decade. The reasons behind these trends are unclear, but could include increasing incidence, detection rates, severity of disease, or age of the population. Morbidity of sarcoidosis is reflected by a trend of increased hospitalizations over recent years and increased use of healthcare resources. Morbidity can be caused by organ damage from granulomatous inflammation, treatment complications, and psychosocial effects of the disease. Recent studies are focused on morbidity related to cardiopulmonary complications, bone health, and aging within the sarcoidosis population. Last, sarcoidosis is associated with autoimmune diseases, pulmonary embolism, and malignancy; however, the underlying mechanisms linking diseases continue to be debated. Summary Morbidity in sarcoidosis is significant and multifactorial. Mortality is infrequent, but may be increasing over the years. PMID:25029298

  19. Life history as a predictor of salamander recovery rate from timber harvest in southern appalachian forests, USA.

    PubMed

    Connette, Grant M; Semlitsch, Raymond D

    2013-12-01

    Forest management often represents a balance between social, economic, and ecological objectives. In the eastern United States, numerous studies have established that terrestrial salamander populations initially decline in abundance following timber harvest, yet the large-scale and long-term consequences are relatively unknown. We used count data from terrestrial survey points to examine the relation between salamander abundance and historic timber harvest while accounting for imperfect detection of individuals. Overall, stream- and terrestrial-breeding salamanders appeared to differ by magnitude of population decline, rate of population recovery, and extent of recolonization from surrounding forest. Specifically, estimated abundance of both species groups was positively associated with stand age and recovery rates were predicted to increase over time for red-legged salamanders (Plethodon shermani) and decrease in stream-breeding species. Abundance of stream-breeding salamanders was predicted to reach a peak by 100 years after timber harvest, and the population growth rate of red-legged salamanders was predicted to undergo a significant increase 100 years after harvest. Estimated abundance of stream-breeding salamanders in young forest stands was also negatively associated with the distance to adjacent forest, a result that suggests immigration has a role in the recovery of these species. Our results indicate that salamander abundance in young forest stands may be only modestly lower than in more mature forest but that full recovery from timber harvest may take a substantial amount of time and that species life history may affect patterns of recovery. Historia de Vida como un Vaticinador de la Tasa de Recuperación de una Salamandra a la Colecta de Madera en los Bosques del Sur de los Apalaches, E.U.A. PMID:24033390

  20. Abundances of northwestern salamander larvae in montane lakes with and without fish, Mount Rainier National Park, Washington

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.

    2002-01-01

    In Mount Rainier National Park, the northwestern salamander usually inhabits relatively large and deep lakes and ponds (average size = 0.3 ha; average depth > 2 m) that contain flocculent, organic bottom sediments and abundant coarse wood. Prior to 1970, salmonids were introduced into many of the park's lakes and ponds that were typical habitat of the northwestern salamander. The objective of this study was to compare, in lakes and ponds with suitable habitat characteristics for northwestern salamanders, the observed abundances of larvae in takes and ponds with and without these introduced salmonids. Day surveys of 61 lakes were conducted between 1993 and 1999. Fish were limited to takes and ponds deeper than 2 in. For the 48 lakes and ponds deeper than 2 in (i.e., 25 fishless lakes and 23 fish lakes), the mean and median observed abundances of northwestern salamander larvae in fishless lakes and ponds was significantly greater than the mean and median observed abundances of larvae in lakes and ponds with fish. Northwestern salamander larvae were not observed in 11 fish lakes. These lakes were similar in median elevation, surface area, and maximum depth to the fishless lakes. The 12 fish lakes with observed larvae were significantly lower in median elevation, larger in median surface area, and deeper in median maximum depth than the fishless lakes. Low to null observed abundances of northwestern salamander larvae in lakes and ponds with fish were attributed to a combination of fish predation of larvae and changes in larval behavior.

  1. Immunologic Biomarkers, Morbidity, and Mortality in Treated HIV Infection.

    PubMed

    Hunt, Peter W; Lee, Sulggi A; Siedner, Mark J

    2016-10-01

    Despite marked improvements in the modern treatment era, human immunodeficiency virus (HIV)-infected individuals, particularly those who initiated antiretroviral therapy (ART) at advanced disease stages, continue to have increased age-related morbidity and mortality, compared with the general population. Immune activation and inflammation persist despite suppressive ART and predict many of these morbidities. The goal of this review is to examine the evidence suggesting a link between the persistent inflammatory state and morbidity and mortality in this setting, to describe the impact of early ART initiation on these factors, and to highlight important unanswered questions for the field. We also advance a hypothesis to explain why some morbidities-and their root inflammatory drivers-may be prevented more than others by early ART initiation. PMID:27625430

  2. Respiratory disease and cardiovascular morbidity

    PubMed Central

    Koskela, R; Mutanen, P; Sorsa, J; Klockars, M

    2005-01-01

    Background: Work related dust exposure is a risk factor for acute and chronic respiratory irritation and inflammation. Exposure to dust and cigarette smoke predisposes to exogenous viral and bacterial infections of the respiratory tract. Respiratory infection can also act as a risk factor in the development of atherosclerotic and coronary artery disease. Aims: To investigate the association of dust exposure and respiratory diseases with ischaemic heart disease (IHD) and other cardiovascular diseases (CVDs). Methods: The study comprised 6022 dust exposed (granite, foundry, cotton mill, iron foundry, metal product, and electrical) workers hired in 1940–76 and followed until the end of 1992. National mortality and morbidity registers and questionnaires were used. The statistical methods were person-year analysis and Cox regression. Results: Co-morbidity from cardiovascular and respiratory diseases ranged from 17% to 35%. In at least 60% of the co-morbidity cases a respiratory disease preceded a cardiovascular disease. Chronic bronchitis, pneumonia, and upper respiratory track infections predicted IHD in granite workers (rate ratio (RR) = 1.9; 95% CI 1.38 to 2.72), foundry workers (2.1; 1.48 to 2.93), and iron foundry workers (1.7; 1.16 to 2.35). Dust exposure was not a significant predictor of IHD or other CVD in any group. Dust exposure was related to respiratory morbidity. Thus, some respiratory diseases appeared to act as intermediate variables in the association of dust exposure with IHD. Conclusion: Dust exposure had only a small direct effect on IHD and other CVD. IHD morbidity was associated with preceding respiratory morbidity. A chronic infectious respiratory tract disease appeared to play an independent role in the development of IHD. PMID:16109822

  3. [Peculiarities of phosphoglycerate kinase-1 pseudogene evolution in Schrenck salamander (Salamandrella schrenckii Strauch, 1870)].

    PubMed

    Malyarchuk, B A; Denisova, G A; Derenko, M V

    2013-07-01

    Processed copies of genes generally evolve in neutral mode as pseudogenes, however, some of them might be important sources of new functional genes. The psiPGK1 pseudogene has been discovered in Schrenck salamander (Salamandrella schrenckii, Amphibia, Caudata, Hynobiidae) via polymerase chain reaction used to amplify the phosphoglycerate kinase 1 gene (PGK1). This pseudogene is an intronless copy of PGK1 gene absent of exon 6. Analysis of psiPGK1 pseudogene polymorphism has demonstrated that it lacks mutations, which results in shifts in the stop codons and reading frames, as well as that the interspecies variation of this pseudogene was inconsistent with the neutral model of evolution. In addition, the pattern of phylogeographic differentiation of the psiPGK1 variants mainly coincides with that observed in mitochondrial DNA. These observations allow it to be suggested that the psiPGK1 pseudogene is a new functional gene in the Schrenck salamander. PMID:24450152

  4. Distribution of the Sonora Tiger Salamander (Ambystoma mavortium stebbinsi) in Mexico

    USGS Publications Warehouse

    Hossack, Blake R.; Muths, Erin L.; Rorabaugh, James C.; Lemos Espinal, Julio A.; Sigafus, Brent H.; Chambert, Thierry A; Carreon Arroyo, Gerardo; Hurtado Felix, David; Toyos Martinez, Daniel; Jones, Thomas R

    2016-01-01

    The Sonoran Tiger Salamander (Ambystoma mavortium stebbinsi Lowe, 1954) was listed as federally endangered in the USA in 1997 (USFWS 1997). In the USA, the distribution of A. mavortium stebbinsi is limited to the San Rafael Valley (approximately 567 km2), between the Sierra San Antonio (called the Patagonia Mountains in Arizona) and Huachuca Mountains, and south of the Canelo Hills, Arizona (Fig. 1). The USA listing was triggered by loss of natural wetland habitats, threats from invasive predators, frequent die-offs from disease, introgression with the introduced Barred Tiger Salamander (A. mavortium mavortium), and small range and number of breeding sites that increases susceptibility to stochastic events (USFWS 1997). Small population sizes and limited gene flow have caused inbreeding, which may further reduce population viability and the potential for recovery (Jones et al. 1988; Storfer et al. 2014). 

  5. Embryo Development inside Female Salamander (Ambystoma jeffersonianum-laterale) Prior to Egg Laying

    PubMed Central

    Charney, Noah D.; Castorino, John J.; Dobro, Megan J.; Steely, Sarah L.

    2014-01-01

    The length of embryo retention prior to oviposition is a critical evolutionary trait. In all oviparous salamanders, which include the vast majority of species in the order, fertilization is thought to occur at the time of egg laying. Embryos then enter the first cleavage stage several hours after being deposited. This pattern holds for previously studied individuals in the Ambystoma jeffersonianum-laterale complex. Here, we document an instance in which a female Ambystoma jeffersonianum-laterale was carrying embryos internally that had already reached stage 10 of development. Development likely began several days prior to the start of migration to the breeding pond. This is the first such record for any egg-laying salamander, and suggests a degree of plasticity in the timing of fertilization and development not previously recognized. Further work is needed to ascertain the prevalence, mechanics, and evolutionary significance of this phenomenon. PMID:24651275

  6. Effects of Histamine on Light Responses of Amacrine Cells in Tiger Salamander Retina

    PubMed Central

    Yu, Yongchun; Satoh, Hiromasa; Vila, Alejandro; Wu, Samuel M.; Marshak, David W.

    2011-01-01

    Using immunofluorescence, we showed that histamine receptor 1 is expressed by horizontal cell axons and a subset of amacrine cells in the tiger salamander retina. The effects of histamine on light responses of amacrine cells were studied in slice preparations. Histamine modulated the light responses of many salamander amacrine cells, depending upon the morphological type. The most pronounced effects of histamine were decreases in the light responses of broadly stratified amacrine cells, particularly those having medium-sized dendritic field diameters. To determine whether the effects of histamine were direct, Co++ was substituted for Ca++ in the extracellular medium to block synaptic transmission. Histamine still affected broadly stratified amacrine cells, but not narrowly stratified amacrine cells under these conditions. Taken together, these findings suggest that inhibitory interactions between strata of the IPL and within the classical receptive fields of the ganglion cells would be particularly sensitive to histamine released from retinopetal axons. PMID:20878231

  7. SURGICAL IMPLANTATION OF COELOMIC RADIOTRANSMITTERS AND POSTOPERATIVE SURVIVAL OF CHINESE GIANT SALAMANDERS (ANDRIAS DAVIDIANUS) FOLLOWING REINTRODUCTION.

    PubMed

    Marcec, Ruth; Kouba, Andrew; Zhang, Lu; Zhang, Hongxing; Wang, Qijun; Zhao, Hu; Jiang, Wei; Willard, Scott

    2016-03-01

    Worldwide, there are only a handful of reintroduction programs for threatened salamander species, and very few have conducted postrelease studies to examine survival, habitat selection, and dispersal. Limitations in postrelease monitoring are primarily due to size constraints of amphibians and to dimensions of the radiotransmitters available for implantation. However, due to the large size of the critically endangered Chinese giant salamander (Andrias davidianus), these animals make optimal candidates for surgical implantation of radiotransmitters prior to reintroduction or translocation. The objective of this study was to develop an anesthetic protocol using tricane methanesulfonate (MS-222) and test a surgical procedure for coelomic implantation of radiotransmitters for this species. A total of 32 Chinese giant salamanders from two age groups (Group A: 4.7 yr old, n = 16; Group B: 2.7 yr old, n = 16) were implanted with 4-g radiotransmitters designed for underwater monitoring of fish. Group A was held 16 wk before release while Group B was held 6 wk before release, and the salamanders' survival and postoperative complications recorded for the first month postrelease. Group A animals took longer to reach a surgical plane of anesthesia than did Group B animals, and this was directly correlated to mass of the animals. Postsurgery, one animal from Group B died of dehiscence before release while 83.9% animals survived after the first month in the wild. All of the animals that died postrelease were from Group B; three animals experienced dehiscence of the suture site and died while another two animals expired from trauma and fungal infection, respectively. Improvements for future studies include use of alternative suture material for closure after implantation and additional healing time of the incision. PMID:27010279

  8. Microbial community dynamics and effect of environmental microbial reservoirs on red-backed salamanders (Plethodon cinereus)

    PubMed Central

    Loudon, Andrew H; Woodhams, Douglas C; Parfrey, Laura Wegener; Archer, Holly; Knight, Rob; McKenzie, Valerie; Harris, Reid N

    2014-01-01

    Beneficial cutaneous bacteria on amphibians can protect against the lethal disease chytridiomycosis, which has devastated many amphibian species and is caused by the fungus Batrachochytrium dendrobatidis. We describe the diversity of bacteria on red-backed salamanders (Plethodon cinereus) in the wild and the stability of these communities through time in captivity using culture-independent Illumina 16S rRNA gene sequencing. After field sampling, salamanders were housed with soil from the field or sterile media. The captive conditions led to different trajectories of bacterial communities. Eight OTUs present on >90% of salamanders in the field, through time, and in both treatments were defined as the core community, suggesting that some bacteria are closely associated with the host and are independent of an environmental reservoir. One of these taxa, a Pseudomonas sp., was previously cultured from amphibians and found to be antifungal. As all host-associated bacteria were found in the soil reservoir, environmental microbes strongly influence host–microbial diversity and likely regulate the core community. Using PICRUSt, an exploratory bioinformatics tool to predict gene functions, we found that core skin bacteria provided similar gene functions to the entire community. We suggest that future experiments focus on testing whether core bacteria on salamander skin contribute to the observed resistance to chytridiomycosis in this species even under hygenic captive conditions. For disease-susceptible hosts, providing an environmental reservoir with defensive bacteria in captive-rearing programs may improve outcomes by increasing bacterial diversity on threatened amphibians or increasing the likelihood that defensive bacteria are available for colonization. PMID:24335825

  9. Trends in Ranavirus Prevalence Among Plethodontid Salamanders in the Great Smoky Mountains National Park.

    PubMed

    Sutton, William B; Gray, Matthew J; Hoverman, Jason T; Secrist, Richard G; Super, Paul E; Hardman, Rebecca H; Tucker, Jennifer L; Miller, Debra L

    2015-06-01

    Emerging pathogens are a potential contributor to global amphibian declines. Ranaviruses, which infect ectothermic vertebrates and are common in aquatic environments, have been implicated in die-offs of at least 72 amphibian species worldwide. Most studies on the subject have focused on pool-breeding amphibians, and infection trends in other amphibian species assemblages have been understudied. Our primary study objective was to evaluate hypotheses explaining ranavirus prevalence within a lungless salamander assemblage (Family Plethodontidae) in the Great Smoky Mountains National Park, USA. We sampled 566 total plethodontid salamanders representing 14 species at five sites over a 6-year period (2007-2012). We identified ranavirus-positive individuals in 11 of the 14 (78.6%) sampled species, with salamanders in the genus Desmognathus having greatest infection prevalence. Overall, we found the greatest support for site elevation and sampling year determining infection prevalence. We detected the greatest number of infections in 2007 with 82.5% of sampled individuals testing positive for ranavirus, which we attribute to record drought during this year. Infection prevalence remained relatively high in low-elevation sites in 2008 and 2009. Neither body condition nor aquatic dependence was a significant predictor of ranavirus prevalence. Overall, our results indicate that life history differences among species play a minor role determining ranavirus prevalence compared to the larger effects of site elevation and yearly fluctuations (likely due to environmental stressors) during sampling years. PMID:25537630

  10. Variable infection of stream salamanders in the southern Appalachians by the trematode Metagonimoides oregonensis (family: Heterophyidae).

    PubMed

    Wyderko, Jennie A; Benfield, Ernest F; Maerz, John C; Cecala, Kristen C; Belden, Lisa K

    2015-08-01

    Many factors contribute to parasites varying in host specificity and distribution among potential hosts. Metagonimoides oregonensis is a digenetic trematode that uses stream-dwelling plethodontid salamanders as second intermediate hosts in the Eastern US. We completed a field survey to identify which stream salamander species, at a regional level, are most likely to be important for transmission to raccoon definitive hosts. We surveyed six plethodontid species (N = 289 salamanders) from 23 Appalachian headwater sites in North Carolina: Desmognathus quadramaculatus (n = 69), Eurycea wilderae (n = 160), Desmognathus ocoee (n = 31), Desmognathus monticola (n = 3), Eurycea guttolineata (n = 7), and Gyrinophilus porphyriticus (n = 19). We found infection in all species except D. monticola. Further analysis focused on comparing infection in the two most abundant species, D. quadramaculatus and E. wilderae. We found that D. quadramaculatus had significantly higher infection prevalence and intensity, probably due to a longer aquatic larval period and larger body sizes and thus greater cumulative exposure to the parasite. PMID:26026670

  11. Amphibian chemical defense: antifungal metabolites of the microsymbiont Janthinobacterium lividum on the salamander Plethodon cinereus.

    PubMed

    Brucker, Robert M; Harris, Reid N; Schwantes, Christian R; Gallaher, Thomas N; Flaherty, Devon C; Lam, Brianna A; Minbiole, Kevin P C

    2008-11-01

    Disease has spurred declines in global amphibian populations. In particular, the fungal pathogen Batrachochytrium dendrobatidis has decimated amphibian diversity in some areas unaffected by habitat loss. However, there is little evidence to explain how some amphibian species persist despite infection or even clear the pathogen beyond detection. One hypothesis is that certain bacterial symbionts on the skin of amphibians inhibit the growth of the pathogen. An antifungal strain of Janthinobacterium lividum, isolated from the skin of the red-backed salamander Plethodon cinereus, produces antifungal metabolites at concentrations lethal to B. dendrobatidis. Antifungal metabolites were identified by using reversed phase high performance liquid chromatography, high resolution mass spectrometry, nuclear magnetic resonance, and UV-Vis spectroscopy and tested for efficacy of inhibiting the pathogen. Two metabolites, indole-3-carboxaldehyde and violacein, inhibited the pathogen's growth at relatively low concentrations (68.9 and 1.82 microM, respectively). Analysis of fresh salamander skin confirmed the presence of J. lividum and its metabolites on the skin of host salamanders in concentrations high enough to hinder or kill the pathogen (51 and 207 microM, respectively). These results support the hypothesis that cutaneous, mutualistic bacteria play a role in amphibian resistance to fungal disease. Exploitation of this biological process may provide long-term resistance to B. dendrobatidis for vulnerable amphibians and serve as a model for managing future emerging diseases in wildlife populations. PMID:18949519

  12. Data set for transcriptome analysis of the Chinese giant salamander (Andrias davidianus )

    PubMed Central

    Jiang, Xuemei; Wang, Yuan; Zhang, Xiaoying

    2015-01-01

    The Chinese giant salamander (Andrias davidianus) occupies a seat at the phylogenetic and species evolution process, which makes it an invaluable model for genetics; however, the genetic information and gene sequences about the Chinese giant salamander in public databases are scanty. Hence, we aimed to perform transcriptome analysis with the help of high-throughput sequencing. In this data, 61,317,940 raw reads were acquired from Chinese giant salamander mRNA using Illumina paired-end sequencing platform. After de novo assembly, a total of 72,072 unigenes were gained, in which 33,834 (46.95%) and 29,479 (40.91%) transcripts exhibited homology to sequences in the Nr database and Swiss-Prot database, (E-value <10−5), respectively. In the obtained unigenes, 18,019 (25%) transcripts were assigned with at least one Gene Ontology term, of which 1218 (6.8%) transcripts were assigned to immune system processes. In addition, a total of 17,572 assembled sequences were assigned into 241 predicted KEGG metabolic pathways. Among these, 2552 (14.5%) transcripts were assigned to the immune system relevant pathway and 5 transcripts were identified as potential antimicrobial peptides (AMPs). PMID:26759822

  13. Data set for transcriptome analysis of the Chinese giant salamander (Andrias davidianus ).

    PubMed

    Jiang, Xuemei; Wang, Yuan; Zhang, Xiaoying

    2016-03-01

    The Chinese giant salamander (Andrias davidianus) occupies a seat at the phylogenetic and species evolution process, which makes it an invaluable model for genetics; however, the genetic information and gene sequences about the Chinese giant salamander in public databases are scanty. Hence, we aimed to perform transcriptome analysis with the help of high-throughput sequencing. In this data, 61,317,940 raw reads were acquired from Chinese giant salamander mRNA using Illumina paired-end sequencing platform. After de novo assembly, a total of 72,072 unigenes were gained, in which 33,834 (46.95%) and 29,479 (40.91%) transcripts exhibited homology to sequences in the Nr database and Swiss-Prot database, (E-value <10(-5)), respectively. In the obtained unigenes, 18,019 (25%) transcripts were assigned with at least one Gene Ontology term, of which 1218 (6.8%) transcripts were assigned to immune system processes. In addition, a total of 17,572 assembled sequences were assigned into 241 predicted KEGG metabolic pathways. Among these, 2552 (14.5%) transcripts were assigned to the immune system relevant pathway and 5 transcripts were identified as potential antimicrobial peptides (AMPs). PMID:26759822

  14. Biogeography and body size shuffling of aquatic salamander communities on a shifting refuge

    PubMed Central

    Bonett, Ronald M.; Trujano-Alvarez, Ana Lilia; Williams, Michael J.; Timpe, Elizabeth K.

    2013-01-01

    Freshwater habitats of coastal plains are refugia for many divergent vertebrate lineages, yet these environments are highly vulnerable to sea-level fluctuations, which suggest that resident communities have endured dynamic histories. Using the fossil record and a multi-locus nuclear phylogeny, we examine divergence times, biogeography, body size evolution and patterns of community assembly of aquatic salamanders from North American coastal plains since the Late Cretaceous. At least five salamander families occurred on the extensive Western Interior Coastal Plain (WICP), which existed from the Late Cretaceous through the Eocene. Four of these families subsequently colonized the emergent Southeastern Coastal Plain (SECP) by the Early Oligocene to Late Miocene. Three families ultimately survived and underwent extensive body size evolution in situ on the SECP. This included at least two major size reversals in recent taxa that are convergent with confamilial WICP ancestors. Dynamics of the coastal plain, major lineage extinctions and frequent extreme changes in body size have resulted in significant shuffling of the size structure of aquatic salamander communities on this shifting refuge since the Cretaceous. PMID:23466988

  15. Co-option and evolution of non-olfactory proteinaceous pheromones in a terrestrial lungless salamander.

    PubMed

    Doty, Kari A; Wilburn, Damien B; Bowen, Kathleen E; Feldhoff, Pamela W; Feldhoff, Richard C

    2016-03-01

    Gene co-option is a major force in the evolution of novel biological functions. In plethodontid salamanders, males deliver proteinaceous courtship pheromones to the female olfactory system or transdermally to the bloodstream. Molecular studies identified three families of highly duplicated, rapidly evolving pheromones (PRF, PMF, and SPF). Analyses for Plethodon salamanders revealed pheromone mixtures of primarily PRF and PMF. The current study demonstrates that in Desmognathus ocoee--a plesiomorphic species with transdermal delivery--SPF is the major pheromone component representing >30% of total protein. Chromatographic profiles of D. ocoee pheromones were consistent from May through October. LC/MS-MS analysis suggested uniform SPF isoform expression between individual male D. ocoee. A gene ancestry for SPF with the Three-Finger Protein superfamily was supported by intron-exon boundaries, but not by the disulfide bonding pattern. Further analysis of the pheromone mixture revealed paralogs to peptide hormones that contained mutations in receptor binding regions, such that these novel molecules may alter female physiology by acting as hormone agonists/antagonists. Cumulatively, gene co-option, duplication, and neofunctionalization have permitted recruitment of additional gene families for pheromone activity. Such independent co-option events may be playing a key role in salamander speciation by altering male traits that influence reproductive success. PMID:26385001

  16. Rapid diversification and dispersal during periods of global warming by plethodontid salamanders

    PubMed Central

    Vieites, David R.; Min, Mi-Sook; Wake, David B.

    2007-01-01

    A phylogeny and timescale derived from analyses of multilocus nuclear DNA sequences for Holarctic genera of plethodontid salamanders reveal them to be an old radiation whose common ancestor diverged from sister taxa in the late Jurassic and underwent rapid diversification during the late Cretaceous. A North American origin of plethodontids was followed by a continental-wide diversification, not necessarily centered only in the Appalachian region. The colonization of Eurasia by plethodontids most likely occurred once, by dispersal during the late Cretaceous. Subsequent diversification in Asia led to the origin of Hydromantes and Karsenia, with the former then dispersing both to Europe and back to North America. Salamanders underwent rapid episodes of diversification and dispersal that coincided with major global warming events during the late Cretaceous and again during the Paleocene–Eocene thermal optimum. The major clades of plethodontids were established during these episodes, contemporaneously with similar phenomena in angiosperms, arthropods, birds, and mammals. Periods of global warming may have promoted diversification and both inter- and transcontinental dispersal in northern hemisphere salamanders by making available terrain that shortened dispersal routes and offered new opportunities for adaptive and vicariant evolution. PMID:18077422

  17. Seasonal variation in microhabitat of salamanders: environmental variation or shift of habitat selection?

    PubMed

    Lunghi, Enrico; Manenti, Raoul; Ficetola, Gentile Francesco

    2015-01-01

    Relationships between species and their habitats are not always constant. Different processes may determine changes in species-habitat association: individuals may prefer different habitat typologies in different periods, or they may be forced to occupy a different habitat in order to follow the changing environment. The aim of our study was to assess whether cave salamanders change their habitat association pattern through the year, and to test whether such changes are determined by environmental changes or by changes in preferences. We monitored multiple caves in Central Italy through one year, and monthly measured biotic and abiotic features of microhabitat and recorded Italian cave salamanders distribution. We used mixed models and niche similarity tests to assess whether species-habitat relationships remain constant through the year. Microhabitat showed strong seasonal variation, with the highest variability in the superficial sectors. Salamanders were associated to relatively cold and humid sectors in summer, but not during winter. Such apparent shift in habitat preferences mostly occurred because the environmental gradient changed through the year, while individuals generally selected similar conditions. Nevertheless, juveniles were more tolerant to dry sectors during late winter, when food demand was highest. This suggests that tolerance for suboptimal abiotic conditions may change through time, depending on the required resources. Differences in habitat use are jointly determined by environmental variation through time, and by changes in the preferred habitat. The trade-offs between tolerance and resources requirement are major determinant of such variation. PMID:26290788

  18. Phylogeography of Sardinian Cave Salamanders (Genus Hydromantes) Is Mainly Determined by Geomorphology

    PubMed Central

    Chiari, Ylenia; van der Meijden, Arie; Mucedda, Mauro; Lourenço, João M.; Hochkirch, Axel; Veith, Michael

    2012-01-01

    Detecting the factors that determine the interruption of gene flow between populations is key to understanding how speciation occurs. In this context, caves are an excellent system for studying processes of colonization, differentiation and speciation, since they represent discrete geographical units often with known geological histories. Here, we asked whether discontinuous calcareous areas and cave systems represent major barriers to gene flow within and among the five species of Sardinian cave salamanders (genus Hydromantes) and whether intraspecific genetic structure parallels geographic distance within and among caves. We generated mitochondrial cytochrome b gene sequences from 184 individuals representing 48 populations, and used a Bayesian phylogeographic approach to infer possible areas of cladogenesis for these species and reconstruct historical and current dispersal routes among distinct populations. Our results show deep genetic divergence within and among all Sardinian cave salamander species, which can mostly be attributed to the effects of mountains and discontinuities in major calcareous areas and cave systems acting as barriers to gene flow. While these salamander species can also occur outside caves, our results indicate that there is a very poor dispersal of these species between separate cave systems. PMID:22427830

  19. MORBIDITY AND MORTALITY CHART BOOK

    EPA Science Inventory

    Provides information on the progress being made in the fight against cardiovascular, lung, and blood diseases. It serves as a resource for the Institute as it plans and prioritizes future activities. Compilation of data on the size and trends of morbidity and mortality from the c...

  20. Vertebrate Hosts as Islands: Dynamics of Selection, Immigration, Loss, Persistence, and Potential Function of Bacteria on Salamander Skin

    PubMed Central

    Loudon, Andrew H.; Venkataraman, Arvind; Van Treuren, William; Woodhams, Douglas C.; Parfrey, Laura Wegener; McKenzie, Valerie J.; Knight, Rob; Schmidt, Thomas M.; Harris, Reid N.

    2016-01-01

    Skin bacterial communities can protect amphibians from a fungal pathogen; however, little is known about how these communities are maintained. We used a neutral model of community ecology to identify bacteria that are maintained on salamanders by selection or by dispersal from a bacterial reservoir (soil) and ecological drift. We found that 75% (9/12) of bacteria that were consistent with positive selection, <1% of bacteria that were consistent with random dispersal and none of the bacteria that were consistent under negative selection had a 97% or greater match to antifungal isolates. Additionally we performed an experiment where salamanders were either provided or denied a bacterial reservoir and estimated immigration and loss (emigration and local extinction) rates of bacteria on salamanders in both treatments. Loss was strongly related to bacterial richness, suggesting competition is important for structuring the community. Bacteria closely related to antifungal isolates were more likely to persist on salamanders with or without a bacterial reservoir, suggesting they had a competitive advantage. Furthermore, over-represented and under-represented operational taxonomic units (OTUs) had similar persistence on salamanders when a bacterial reservoir was present. However, under-represented OTUs were less likely to persist in the absence of a bacterial reservoir, suggesting that the over-represented and under-represented bacteria were selected against or for on salamanders through time. Our findings from the neutral model, migration and persistence analyses show that bacteria that exhibit a high similarity to antifungal isolates persist on salamanders, which likely protect hosts against pathogens and improve fitness. This research is one of the first to apply ecological theory to investigate assembly of host associated-bacterial communities, which can provide insights for probiotic bioaugmentation as a conservation strategy against disease. PMID:27014249

  1. Vertebrate Hosts as Islands: Dynamics of Selection, Immigration, Loss, Persistence, and Potential Function of Bacteria on Salamander Skin.

    PubMed

    Loudon, Andrew H; Venkataraman, Arvind; Van Treuren, William; Woodhams, Douglas C; Parfrey, Laura Wegener; McKenzie, Valerie J; Knight, Rob; Schmidt, Thomas M; Harris, Reid N

    2016-01-01

    Skin bacterial communities can protect amphibians from a fungal pathogen; however, little is known about how these communities are maintained. We used a neutral model of community ecology to identify bacteria that are maintained on salamanders by selection or by dispersal from a bacterial reservoir (soil) and ecological drift. We found that 75% (9/12) of bacteria that were consistent with positive selection, <1% of bacteria that were consistent with random dispersal and none of the bacteria that were consistent under negative selection had a 97% or greater match to antifungal isolates. Additionally we performed an experiment where salamanders were either provided or denied a bacterial reservoir and estimated immigration and loss (emigration and local extinction) rates of bacteria on salamanders in both treatments. Loss was strongly related to bacterial richness, suggesting competition is important for structuring the community. Bacteria closely related to antifungal isolates were more likely to persist on salamanders with or without a bacterial reservoir, suggesting they had a competitive advantage. Furthermore, over-represented and under-represented operational taxonomic units (OTUs) had similar persistence on salamanders when a bacterial reservoir was present. However, under-represented OTUs were less likely to persist in the absence of a bacterial reservoir, suggesting that the over-represented and under-represented bacteria were selected against or for on salamanders through time. Our findings from the neutral model, migration and persistence analyses show that bacteria that exhibit a high similarity to antifungal isolates persist on salamanders, which likely protect hosts against pathogens and improve fitness. This research is one of the first to apply ecological theory to investigate assembly of host associated-bacterial communities, which can provide insights for probiotic bioaugmentation as a conservation strategy against disease. PMID:27014249

  2. Multimodal communication, mismatched messages and the effects of turbidity on the antipredator behavior of the Barton Springs salamander, Eurycea sosorum.

    PubMed

    Zabierek, Kristina C; Gabor, Caitlin R

    2016-09-01

    Prey may use multiple sensory channels to detect predators, whose cues may differ in altered sensory environments, such as turbid conditions. Depending on the environment, prey may use cues in an additive/complementary manner or in a compensatory manner. First, to determine whether the purely aquatic Barton Springs salamander, Eurycea sosorum, show an antipredator response to visual cues, we examined their activity when exposed to either visual cues of a predatory fish (Lepomis cyanellus) or a non-predatory fish (Etheostoma lepidum). Salamanders decreased activity in response to predator visual cues only. Then, we examined the antipredator response of these salamanders to all matched and mismatched combinations of chemical and visual cues of the same predatory and non-predatory fish in clear and low turbidity conditions. Salamanders decreased activity in response to predator chemical cues matched with predator visual cues or mismatched with non-predator visual cues. Salamanders also increased latency to first move to predator chemical cues mismatched with non-predator visual cues. Salamanders decreased activity and increased latency to first move more in clear as opposed to turbid conditions in all treatment combinations. Our results indicate that salamanders under all conditions and treatments preferentially rely on chemical cues to determine antipredator behavior, although visual cues are potentially utilized in conjunction for latency to first move. Our results also have potential conservation implications, as decreased antipredator behavior was seen in turbid conditions. These results reveal complexity of antipredator behavior in response to multiple cues under different environmental conditions, which is especially important when considering endangered species. PMID:27370360

  3. Pulmonary function in morbid obesity.

    PubMed

    Sugerman, H J

    1987-06-01

    Morbid obesity is not infrequently associated with severe respiratory impairment. In our experience approximately 10 per cent of morbidly obese patients who underwent gastric surgery had severe respiratory impairment. Respiratory insufficiency of obesity can be divided into two primary breathing disorders: the obstructive sleep apnea syndrome (SAS) and the obesity hypoventilation syndrome (OHS). In its most severe form, when both SAS and OHS are present, it is called the Pickwickian syndrome. In our series 59 morbidly obese patients with respiratory insufficiency secondary to obesity underwent gastric surgery for weight reduction. Fourteen had OHS, 19 had SAS and 26 had both. Of these, two patients died of postoperative complications and one died at five weeks with an inconclusive autopsy, totalling an operative mortality rate of 3.4 per cent and a total mortality of 5.1 per cent. In our overall experience morbidly obese patients lost 67 per cent of excess weight after gastric procedures. In conclusion, surgically induced weight loss will markedly improve or correct respiratory insufficiency secondary to obesity. It will improve arterial oxygenation, minimize CO2 retention, expand lung volumes, correct polycythemia, and reduce apnea frequency. The magnitude of changes in these variables is clinically significant. Therefore, respiratory insufficiency of obesity should be considered a major indication for an aggressive approach to weight reduction. The jejunoileal bypass and unbanded gastroplasty operations have an unacceptable incidence of complications or failure, respectively. There is a high degree of recidivism following dietary programs. Sweets eaters will not do well with a gastroplasty procedure. Gastric bypass for individuals addicted to sweets or the vertical banded gastroplasty for "gorgers" are currently our procedures of choice and are associated with the average loss of two thirds of excess weight and correction of breathing problems associated with

  4. Transcriptional and phylogenetic analysis of five complete ambystomatid salamander mitochondrial genomes.

    PubMed

    Samuels, Amy K; Weisrock, David W; Smith, Jeramiah J; France, Katherine J; Walker, John A; Putta, Srikrishna; Voss, S Randal

    2005-04-11

    We report on a study that extended mitochondrial transcript information from a recent EST project to obtain complete mitochondrial genome sequence for 5 tiger salamander complex species (Ambystoma mexicanum, A. t. tigrinum, A. andersoni, A. californiense, and A. dumerilii). We describe, for the first time, aspects of mitochondrial transcription in a representative amphibian, and then use complete mitochondrial sequence data to examine salamander phylogeny at both deep and shallow levels of evolutionary divergence. The available mitochondrial ESTs for A. mexicanum (N=2481) and A. t. tigrinum (N=1205) provided 92% and 87% coverage of the mitochondrial genome, respectively. Complete mitochondrial sequences for all species were rapidly obtained by using long distance PCR and DNA sequencing. A number of genome structural characteristics (base pair length, base composition, gene number, gene boundaries, codon usage) were highly similar among all species and to other distantly related salamanders. Overall, mitochondrial transcription in Ambystoma approximated the pattern observed in other vertebrates. We inferred from the mapping of ESTs onto mtDNA that transcription occurs from both heavy and light strand promoters and continues around the entire length of the mtDNA, followed by post-transcriptional processing. However, the observation of many short transcripts corresponding to rRNA genes indicates that transcription may often terminate prematurely to bias transcription of rRNA genes; indeed an rRNA transcription termination signal sequence was observed immediately following the 16S rRNA gene. Phylogenetic analyses of salamander family relationships consistently grouped Ambystomatidae in a clade containing Cryptobranchidae and Hynobiidae, to the exclusion of Salamandridae. This robust result suggests a novel alternative hypothesis because previous studies have consistently identified Ambystomatidae and Salamandridae as closely related taxa. Phylogenetic analyses of tiger

  5. Severe maternal morbidity: screening and review.

    PubMed

    Kilpatrick, Sarah K; Ecker, Jeffrey L

    2016-09-01

    This document builds upon recommendations from peer organizations and outlines a process for identifying maternal cases that should be reviewed. Severe maternal morbidity is associated with a high rate of preventability, similar to that of maternal mortality. It also can be considered a near miss for maternal mortality because without identification and treatment, in some cases, these conditions would lead to maternal death. Identifying severe morbidity is, therefore, important for preventing such injuries that lead to mortality and for highlighting opportunities to avoid repeat injuries. The two-step screen and review process described in this document is intended to efficiently detect severe maternal morbidity in women and to ensure that each case undergoes a review to determine whether there were opportunities for improvement in care. Like cases of maternal mortality, cases of severe maternal morbidity merit quality review. In the absence of consensus on a comprehensive list of conditions that represent severe maternal morbidity, institutions and systems should either adopt an existing screening criteria or create their own list of outcomes that merit review. PMID:27560600

  6. Phylogeny and genetic history of the Siberian salamander (Salamandrella keyserlingii, Dybowski, 1870) inferred from complete mitochondrial genomes.

    PubMed

    Malyarchuk, Boris; Derenko, Miroslava; Denisova, Galina

    2013-05-01

    We assessed phylogeny of the Siberian salamander (Salamandrella keyserlingii, Dybowski, 1870), the most northern ectothermic, terrestrial vertebrate in Eurasia, by sequence analysis of complete mitochondrial genomes in 26 specimens from different localities (China, Khabarovsk region, Sakhalin, Yakutia, Magadan region, Chukotka, Kamchatka, Ural, European part of Russia). In addition, a complete mitochondrial genome of the Schrenck salamander, Salamandrella schrenckii, was determined for the first time. Bayesian phylogenetic analysis of the entire mtDNA genomes of S. keyserlingii demonstrates that two haplotype clades, AB and C, radiated about 1.4 million years ago (Mya). Bayesian skyline plots of population size change through time show an expansion around 250 thousand years ago (kya) and then a decline around the Last Glacial Maximum (25 kya) with subsequent restoration of population size. Climatic changes during the Quaternary period have dramatically affected the population genetic structure of the Siberian salamanders. In addition, complete mtDNA sequence analysis allowed us to recognize that the vast area of Northern Eurasia was colonized only by the Siberian salamander clade C1b during the last 150 kya. Meanwhile, we were unable to find evidence of molecular adaptation in this clade by analyzing the whole mitochondrial genomes of the Siberian salamanders. PMID:23415986

  7. Infectious Morbidity After Radical Vulvectomy

    PubMed Central

    Carson, Linda F.; Brooker, Doris C.; Carter, Jonathan R.; Twiggs, Leo B.

    1994-01-01

    Objective: This retrospective investigation describes the infectious morbidity of patients following radical vulvectomy with or without inguinal lymph node dissection. Methods: The charts of patients undergoing radical vulvectomy between January 1, 1986, and September 1, 1989, were reviewed for age, weight, cancer type, tumor stage, operative procedure(s), prophylactic antibiotic and its length of use, febrile morbidity, infection site, culture results, significant medical history, and length of use and number of drains or catheters used. Results: The study group was composed of 61 patients, 14 of whom underwent a radical vulvectomy and 47 who also had inguinal lymph node dissection performed. Twenty-nine patients (48%) had at least 1 postoperative infection. Five patients (8%) had 2 or more postoperative infections. The site and incidence of the infections were as follows: urinary tract 23%, wound 23%, lymphocyst 3%, lymphatics (lymphangitis) 5%, and bowel (pseudomembranous colitis) 3%. The most common pathogens isolated from both urine and wound sites were Pseudomonas aeruginosa, enterococcus, and Escherichia coli. A significant decrease in wound infection was demonstrated when separate incisions were made for inguinal lymph node dissection (P <0.05). The mean number of days to onset of postoperative infection for wound, urine, lymphatics, lymphocyst, and bowel were 11, 8, 57, 48, and 5, respectively. Conclusions: We conclude that the clinical appearance of post-radical vulvectomy infections is delayed when compared with other post-surgical wound infections. Second, utilizing separate inguinal surgical incisions may reduce infectious morbidity. Finally, tumor stage and type do not necessarily increase the infectious morbidity of radical vulvar surgery. PMID:18475379

  8. Influence of observers and stream flow on northern two-lined salamander (Eurycea bislineata bislineata) relative abundance estimates in Acadia and Shenandoah National Parks, USA

    USGS Publications Warehouse

    Crocker, J.B.; Bank, M.S.; Loftin, C.S.; Jung Brown, R.E.

    2007-01-01

    We investigated effects of observers and stream flow on Northern Two-Lined Salamander (Eurycea bislineata bislineata) counts in streams in Acadia (ANP) and Shenandoah National Parks (SNP). We counted salamanders in 22 ANP streams during high flow (May to June 2002) and during low flow (July 2002). We also counted salamanders in SNP in nine streams during high flow (summer 2003) and 11 streams during low flow (summers 2001?02, 2004). In 2002, we used a modified cover-controlled active search method with a first and second observer. In succession, observers turned over 100 rocks along five 1-m belt transects across the streambed. The difference between observers in total salamander counts was not significant. We counted fewer E. b. bislineata during high flow conditions, confirming that detection of this species is reduced during high flow periods and that assessment of stream salamander relative abundance is likely more reliable during low or base flow conditions.

  9. Metals, Parasites, and Environmental Conditions Affecting Breeding Populations of Spotted Salamanders (Ambystoma maculatum) in Northern Arkansas, USA.

    PubMed

    DeMali, Heather M; Trauth, Stanley E; Bouldin, Jennifer L

    2016-06-01

    The spotted salamander (Ambystoma maculatum) is indigenous to northern Arkansas, and several breeding sites are known to exist in the region. Spotted salamanders (n = 17) were collected and examined for parasites and only three females harbored nematodes (Physaloptera spp.). Chronic aquatic bioassays were conducted using water collected from eight breeding ponds during different hydroperiod events. No lethal or sublethal effects were measured in Ceriodaphnia dubia; however, decreased growth and survival were seen in Pimephales promelas. Aqueous, sediment, and salamander hepatic samples were analyzed for As, Cd, Cu, Pb, and Ni. Metal analysis revealed possible increased metal exposure following precipitation, with greatest metal concentrations measured in sediment samples. Hepatic metal concentrations were similar in parasitized and non-parasitized individuals, and greatest Pb concentrations were measured following normal precipitation events. Determining environmental stressors of amphibians, especially during their breeding and subsequent larval life stage, is imperative to improve species conservation. PMID:26886425

  10. Gastrointestinal Symptoms in Morbid Obesity

    PubMed Central

    Huseini, Mustafa; Wood, G. Craig; Seiler, Jamie; Argyropoulos, George; Irving, Brian A.; Gerhard, Glenn S.; Benotti, Peter; Still, Christopher; Rolston, David D. K.

    2014-01-01

    Background: Several reports have shown an increased prevalence of gastrointestinal (GI) symptoms in obese subjects in community-based studies. To better understand the role of the GI tract in obesity, and because there are limited clinic-based studies, we documented the prevalence of upper and lower GI symptoms in morbidly obese individuals in a clinic setting. Objective: The aim of our study was to compare the prevalence of GI symptoms in morbidly obese individuals in a weight management clinic with non-obese individuals with similar comorbidities as morbidly obese individuals in an Internal Medicine clinic. Methods: Class II and III obese patients BMI >35 kg/m2 (N = 114) and 182 non-obese patients (BMI <25 kg/m2) completed the GI symptoms survey between August 2011 and April 2012 were included in this study. The survey included 24 items pertaining to upper and lower GI symptoms. The participants rated the frequency of symptoms as absent (never, rarely) or present (occasionally, frequently). The symptoms were clustered into five categories: oral symptoms, dysphagia, gastroesophageal reflux, abdominal pain, and bowel habits. Responses to each symptom cluster were compared between obese group and normal weight groups using logistic regression. Results: Of the 24 items, 18 had a higher frequency in the obese group (p < 0.005 for each). After adjusting for age and gender, the obese patients were more likely to have upper GI symptoms: any oral symptom (OR = 2.3, p = 0.0013), dysphagia (OR 2.9, p = 0.0006), and any gastroesophageal reflux (OR 3.8, p < 0.0001). Similarly, the obese patients were more likely to have lower GI symptoms: any abdominal pain (OR = 1.7, p = 0.042) and altered bowel habits (OR = 2.8, p < 0.0001). Conclusion: These observations suggest a statistically significant increase in frequency of both upper and lower GI symptoms in morbidly obese patients when compared to non-obese subjects. PMID:25593922

  11. Dose rate estimation of the Tohoku hynobiid salamander, Hynobius lichenatus, in Fukushima.

    PubMed

    Fuma, Shoichi; Ihara, Sadao; Kawaguchi, Isao; Ishikawa, Takahiro; Watanabe, Yoshito; Kubota, Yoshihisa; Sato, Youji; Takahashi, Hiroyuki; Aono, Tatsuo; Ishii, Nobuyoshi; Soeda, Haruhi; Matsui, Kumi; Une, Yumi; Minamiya, Yukio; Yoshida, Satoshi

    2015-05-01

    The radiological risks to the Tohoku hynobiid salamanders (class Amphibia), Hynobius lichenatus due to the Fukushima Dai-ichi Nuclear Power Plant accident were assessed in Fukushima Prefecture, including evacuation areas. Aquatic egg clutches (n = 1 for each sampling date and site; n = 4 in total), overwintering larvae (n = 1-5 for each sampling date and site; n = 17 in total), and terrestrial juveniles or adults (n = 1 or 3 for each sampling date and site; n = 12 in total) of H. lichenatus were collected from the end of April 2011 to April 2013. Environmental media such as litter (n = 1-5 for each sampling date and site; n = 30 in total), soil (n = 1-8 for each sampling date and site; n = 31 in total), water (n = 1 for each sampling date and site; n = 17 in total), and sediment (n = 1 for each sampling date and site; n = 17 in total) were also collected. Activity concentrations of (134)Cs + (137)Cs were 1.9-2800, 0.13-320, and 0.51-220 kBq (dry kg) (-1) in the litter, soil, and sediment samples, respectively, and were 0.31-220 and <0.29-40 kBq (wet kg)(-1) in the adult and larval salamanders, respectively. External and internal absorbed dose rates to H. lichenatus were calculated from these activity concentration data, using the ERICA Assessment Tool methodology. External dose rates were also measured in situ with glass dosimeters. There was agreement within a factor of 2 between the calculated and measured external dose rates. In the most severely contaminated habitat of this salamander, a northern part of Abukuma Mountains, the highest total dose rates were estimated to be 50 and 15 μGy h(-1) for the adults and overwintering larvae, respectively. Growth and survival of H. lichenatus was not affected at a dose rate of up to 490 μGy h(-1) in the previous laboratory chronic gamma-irradiation experiment, and thus growth and survival of this salamander would not be affected, even in the most severely contaminated habitat in Fukushima Prefecture. However, further

  12. Using counts to simultaneously estimate abundance and detection probabilities in a salamander community

    USGS Publications Warehouse

    Dodd, C.K., Jr.; Dorazio, R.M.

    2004-01-01

    A critical variable in both ecological and conservation field studies is determining how many individuals of a species are present within a defined sampling area. Labor intensive techniques such as capture-mark-recapture and removal sampling may provide estimates of abundance, but there are many logistical constraints to their widespread application. Many studies on terrestrial and aquatic salamanders use counts as an index of abundance, assuming that detection remains constant while sampling. If this constancy is violated, determination of detection probabilities is critical to the accurate estimation of abundance. Recently, a model was developed that provides a statistical approach that allows abundance and detection to be estimated simultaneously from spatially and temporally replicated counts. We adapted this model to estimate these parameters for salamanders sampled over a six vear period in area-constrained plots in Great Smoky Mountains National Park. Estimates of salamander abundance varied among years, but annual changes in abundance did not vary uniformly among species. Except for one species, abundance estimates were not correlated with site covariates (elevation/soil and water pH, conductivity, air and water temperature). The uncertainty in the estimates was so large as to make correlations ineffectual in predicting which covariates might influence abundance. Detection probabilities also varied among species and sometimes among years for the six species examined. We found such a high degree of variation in our counts and in estimates of detection among species, sites, and years as to cast doubt upon the appropriateness of using count data to monitor population trends using a small number of area-constrained survey plots. Still, the model provided reasonable estimates of abundance that could make it useful in estimating population size from count surveys.

  13. The role of climate in the dynamics of a hybrid zone in Appalachian salamanders

    USGS Publications Warehouse

    Walls, Susan

    2009-01-01

    I examined the potential influence of climate change on the dynamics of a previously studied hybrid zone between a pair of terrestrial salamanders at the Coweeta Hydrologic Laboratory, U.S. Forest Service, in the Nantahala Mountains of North Carolina, USA. A 16-year study led by Nelson G. Hairston, Sr. revealed that Plethodon teyahalee and Plethodon shermani hybridized at intermediate elevations, forming a cline between 'pure' parental P. teyahalee at lower elevations and 'pure' parental P. shermani at higher elevations. From 1974 to 1990 the proportion of salamanders at the higher elevation scored as 'pure' P. shermani declined significantly, indicating that the hybrid zone was spreading upward. To date there have been no rigorous tests of hypotheses for the movement of this hybrid zone. Using temperature and precipitation data from Coweeta, I re-analyzed Hairston's data to examine whether the observed elevational shift was correlated with variation in either air temperature or precipitation from the same time period. For temperature, my analysis tracked the results of the original study: the proportion of 'pure' P. shermani at the higher elevation declined significantly with increasing mean annual temperature, whereas the proportion of 'pure' P. teyahalee at lower elevations did not. There was no discernable relationship between proportions of 'pure' individuals of either species with variation in precipitation. From 1974 to 1990, low-elevation air temperatures at the Coweeta Laboratory ranged from annual means of 11.8 to 14.2 °C, compared with a 55-year average (1936-1990) of 12.6 °C. My re-analyses indicate that the upward spread of the hybrid zone is correlated with increasing air temperatures, but not precipitation, and provide an empirical test of a hypothesis for one factor that may have influenced this movement. My results aid in understanding the potential impact that climate change may have on the ecology and evolution of terrestrial salamanders in

  14. Projected Loss of a Salamander Diversity Hotspot as a Consequence of Projected Global Climate Change

    PubMed Central

    Milanovich, Joseph R.; Peterman, William E.; Nibbelink, Nathan P.; Maerz, John C.

    2010-01-01

    Background Significant shifts in climate are considered a threat to plants and animals with significant physiological limitations and limited dispersal abilities. The southern Appalachian Mountains are a global hotspot for plethodontid salamander diversity. Plethodontids are lungless ectotherms, so their ecology is strongly governed by temperature and precipitation. Many plethodontid species in southern Appalachia exist in high elevation habitats that may be at or near their thermal maxima, and may also have limited dispersal abilities across warmer valley bottoms. Methodology/Principal Findings We used a maximum-entropy approach (program Maxent) to model the suitable climatic habitat of 41 plethodontid salamander species inhabiting the Appalachian Highlands region (33 individual species and eight species included within two species complexes). We evaluated the relative change in suitable climatic habitat for these species in the Appalachian Highlands from the current climate to the years 2020, 2050, and 2080, using both the HADCM3 and the CGCM3 models, each under low and high CO2 scenarios, and using two-model thresholds levels (relative suitability thresholds for determining suitable/unsuitable range), for a total of 8 scenarios per species. Conclusion/Significance While models differed slightly, every scenario projected significant declines in suitable habitat within the Appalachian Highlands as early as 2020. Species with more southern ranges and with smaller ranges had larger projected habitat loss. Despite significant differences in projected precipitation changes to the region, projections did not differ significantly between global circulation models. CO2 emissions scenario and model threshold had small effects on projected habitat loss by 2020, but did not affect longer-term projections. Results of this study indicate that choice of model threshold and CO2 emissions scenario affect short-term projected shifts in climatic distributions of species; however

  15. Behavioral and physiological antipredator responses of the San Marcos salamander, Eurycea nana.

    PubMed

    Davis, Drew R; Gabor, Caitlin R

    2015-02-01

    Exposure to predatory stimuli typically results in the elevation of circulating glucocorticoid levels and a behavioral response of freezing or escape behavior in many prey species. Corticosterone (CORT) is the main glucocorticoid in amphibians and is known to be important in modulating many behaviors and developmental functions. The federally threatened San Marcos salamander, Eurycea nana, decreases activity in response to both native and introduced predatory fish, however, experience may further influence these interactions. To better understand the indirect effects of fish predators on this salamander, we examined both the antipredator behavior and water-borne CORT release rates in response to chemical cues (kairomones) from two fish species that varied in temporal risk of predation: (1) a low encounter frequency predator (largemouth bass, Micropterus salmoides), (2) a high encounter frequency predator (redbreast sunfish, Lepomis auritus), and (3) a blank water control. Salamanders reduced activity (antipredator response) after exposure to both predator treatments, but not to the blank water control, and the response to M. salmoides was significantly stronger than that to L. auritus. The CORT response (post-stimulus/pre-stimulus release rates) did not differ between the blank water control and L. auritus treatments, and both were significantly less than the CORT response to M. salmoides. Overall, E. nana showed a decreased antipredator response and no CORT response towards the high encounter frequency L. auritus as compared to the low encounter frequency M. salmoides. Eurycea nana may mute antipredator and CORT responses to high temporal frequency predators. There was, however, no correlation between CORT release rates and antipredator behavior, which suggests that the presence of predators may be affecting CORT response and behavior independently. PMID:25446225

  16. Heterochrony repolarized: a phylogenetic analysis of developmental timing in plethodontid salamanders

    PubMed Central

    2014-01-01

    Background Disentangling evolutionary shifts in developmental timing (heterochony) is dependent upon accurate estimates of ancestral patterns. However, many classic assessments of heterochronic patterns predate robust phylogenetic hypotheses and methods for trait reconstruction, and therefore may have been polarized with untested ‘primitive’ conditions. Here we revisit the heterochronic modes of development that underlie the evolution of metamorphosis, maturation, and paedomorphosis in plethodontid salamanders. We focus on the tribe Spelerpini, which is a diverse clade that exhibits tremendous variation in timing of metamorphosis and maturation, as well as multiple independent instances of larval form paedomorphosis. Based on morphology and biogeography, early investigators concluded that the most recent common ancestors of plethodontids, and also spelerpines, were large salamanders, with very long larval periods and late maturation times. This prevailing assumption influenced subsequent heterochronic assessments, which concluded that most modern spelerpines (with shorter larval periods) were derived through multiple independent accelerations in larval development. It was also concluded that most occurrences of larval form paedomorphosis in this clade resulted from progenesis (acceleration of gonadal development relative to metamorphosis). Results By reconstructing the time to metamorphosis on a molecular-based phylogeny of plethodontids, we find that ancestral spelerpines likely had relatively shorter larval periods than previously proposed. Taken together with the credibility interval from our ancestral state estimation we show that very long larval periods are likely derived decelerations, only a few lineages have undergone appreciable accelerations in metamorphic timing, and the remaining taxa have lower probabilities of being different than the ancestral condition (possibly due to stasis). Reconstructing maturation age across nodes concomitant with the

  17. Plethodontid salamander mitochondrial genomics: A parsimonyevaluation of character conflict and implications for historicalbiogeography

    SciTech Connect

    Macey, J. Robert

    2005-01-19

    A new parsimony analysis of 27 complete mitochondrial genomic sequences is conducted to investigate the phylogenetic relationships of plethodontid salamanders. This analysis focuses on the amount of character conflict between phylogenetic trees recovered from newly conducted parsimony searches and the Bayesian and maximum likelihood topology reported by Mueller et al. (2004, PNAS, 101, 13820-13825). Strong support for Hemidactylium as the sister taxon to all other plethodontids is recovered from parsimony analyses. Plotting area relationships on the most parsimonious phylogenetic tree suggests that eastern North America is the origin of the family Plethodontidae supporting the ''Out of Appalachia'' hypothesis. A new taxonomy that recognizes clades recovered from phylogenetic analyses is proposed.

  18. Escape to Alcatraz: evolutionary history of slender salamanders (Batrachoseps) on the islands of San Francisco Bay

    PubMed Central

    Martínez-Solano, Iñigo; Lawson, Robin

    2009-01-01

    Background Island populations are excellent model systems for studies of phenotypic, ecological and molecular evolution. In this study, molecular markers of mitochondrial and nuclear derivation were used to investigate the evolution, structure and origin of populations of the California slender salamander (Batrachoseps attenuatus) inhabiting the six major islands of San Francisco Bay, formed following the rising of sea level around 9,000 years ago. Results There was a high degree of congruence in the results of analyses of nucleotide and allozyme data, both of which strongly support the hypothesis that, for the majority of the islands, salamanders are descended from hilltop populations that became isolated with the formation of the Bay ca. 9,000 years ago. There are two exceptions (Alcatraz and Yerba Buena) where the evidence suggests that salamander populations are wholly or in part, the result of anthropogenic introductions. Comparison of the molecular data and the interpretations drawn therefrom with an earlier morphological study of many of the same salamander populations show some of the same evolutionary trends. Conclusion In spite of marked differences between the evolutionary rates of the two kinds of molecular markers, both indicate distinctive and similar patterns of population structure for B. attenuatus in the San Francisco Bay Area and its islands. With the two noted exceptions, it is clear that most island populations were established prior to the 9,000 years since the formation of the Bay. Results of coalescence-based analyses suggest that for most island populations the mtDNA lineages from which they were derived date from the Pleistocene. It can be said that, based on observed values of genetic diversity, the last 9,000 years of evolution on these islands have been characterized by relative stability, with the occasional extinction of some haplotypes or alleles that were formerly shared between island and mainland populations but overall

  19. Role of habitat complexity in predator-prey dynamics between an introduced fish and larval Long-toed Salamanders (Ambystoma macrodactylum)

    USGS Publications Warehouse

    Kenison, Erin K; Litt, Andrea R.; Pilliod, David; McMahon, Tom E

    2016-01-01

    Predation by nonnative fishes has reduced abundance and increased extinction risk for amphibian populations worldwide. Although rare, fish and palatable amphibians have been observed to coexist where aquatic vegetation and structural complexity provide suitable refugia. We examined whether larval long-toed salamanders (Ambystoma macrodactylum Baird, 1849) increased use of vegetation cover in lakes with trout and whether adding vegetation structure could reduce predation risk and nonconsumptive effects (NCEs), such as reductions in body size and delayed metamorphosis. We compared use of vegetation cover by larval salamanders in lakes with and without trout and conducted a field experiment to investigate the influence of added vegetation structure on salamander body morphology and life history. The probability of catching salamanders in traps in lakes with trout was positively correlated with the proportion of submerged vegetation and surface cover. Growth rates of salamanders in enclosures with trout cues decreased as much as 85% and the probability of metamorphosis decreased by 56%. We did not find evidence that adding vegetation reduced NCEs in experimental enclosures, but salamanders in lakes with trout utilized more highly-vegetated areas which suggests that adding vegetation structure at the scale of the whole lake may facilitate coexistence between salamanders and introduced trout.

  20. Modification effects of coping on post-traumatic morbidity among earthquake rescuers.

    PubMed

    Chang, Chia-Ming; Lee, Li-Ching; Connor, Kathryn M; Davidson, Jonathan R T; Lai, Te-Jen

    2008-03-15

    This study aims to investigate the modification effects of coping strategies on the relationships between rescue effort and psychiatric morbidity (i.e. general psychiatric morbidity and post-traumatic morbidity) in earthquake rescue workers. Firefighters (n=193) who were involved in the rescue effort after the Taiwan Chi-Chi earthquake were invited to complete a questionnaire which contained questions on demographics, exposure to rescue work, general psychiatric morbidity, post-traumatic morbidity, and coping strategies. Multivariate regression models with interaction terms were carried out to investigate the modification effect of coping strategies on the relationships between rescue effort and psychiatric morbidities. Older age and longer job experiences (>3 years) were associated with both general psychiatric and post-traumatic morbidities. Coping strategies such as confrontive coping, distancing, seeking social support, accepting responsibility, escape-avoidance, planful problem solving, and positive appraisal significantly modified the effect of exposure to dead bodies on general psychiatric morbidity. Furthermore, confrontive coping, distancing, and planned problem solving significantly modified the effect of exposure to direct rescue involvement on general psychiatric morbidity. However, coping strategies were not observed to buffer the effect of rescue involvement or contact with dead bodies on post-traumatic morbidity. More frequent use of coping strategies could reduce the effect that exposure to rescue efforts has on the incidence of general psychiatric morbidity in rescue workers. However, coping strategies do not seem to reduce the influence of such exposure on trauma-related morbidities. This suggests that coping strategies can be used to prevent general psychiatric morbidity but not trauma-related morbidities. PMID:18258306

  1. Persistence and extirpation in invaded landscapes: patch characteristics and connectivity determine effects of non-native predatory fish on native salamanders

    USGS Publications Warehouse

    Pilliod, David S.; Arkle, Robert S.; Maxell, Bryce A.

    2012-01-01

    Studies have demonstrated negative effects of non-native, predatory fishes on native amphibians, yet it is still unclear why some amphibian populations persist, while others are extirpated, following fish invasion. We examined this question by developing habitat-based occupancy models for the long-toed salamander (Ambystoma macrodactylum) and nonnative fish using survey data from 1,749 water bodies across 470 catchments in the Northern Rocky Mountains, USA. We first modeled the habitat associations of salamanders at 468 fishless water bodies in 154 catchments where non-native fish were historically, and are currently, absent from the entire catchment. Wethen applied this habitat model to the complete data set to predict the probability of salamander occupancy in each water body, removing any effect of fish presence. Finally, we compared field-observed occurrences of salamanders and fish to modeled probability of salamander occupancy. Suitability models indicated that fish and salamanders had similar habitat preferences, possibly resulting in extirpations of salamander populations from entire catchments where suitable habitats were limiting. Salamanders coexisted with non-native fish in some catchments by using marginal quality, isolated (no inlet or outlet) habitats that remained fishless. They rarely coexisted with fish within individual water bodies and only where habitat quality was highest. Connectivity of water bodies via streams resulted in increased probability of fish invasion and consequently reduced probability of salamander occupancy.These results could be used to identify and prioritize catchments and water bodies where control measures would be most effective at restoring amphibian populations. Our approach could be useful as a framework for improved investigations into questions of persistence and extirpation of native species when non-native species have already become established.

  2. 76 FR 55413 - Proposed Safe Harbor Agreement for California Red-legged Frog, California Tiger Salamander, Smith...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ... Register on June 17, 1999 (64 FR 32717), the Service would issue a permit to the Applicant authorizing take... Tiger Salamander, Smith's Blue Butterfly, and Yadon's Piperia at Palo Corona Regional Park, Monterey... californiense) and federally endangered Smith's blue butterfly (Euphilotes enoptes smithi) under the...

  3. INFLUENCE OF HABITAT CHARACTERISTICS ON DETECTED SITE OCCUPANCY OF THE NEW MEXICO ENDEMIC SACRAMENTO MOUNTAINS SALAMANDER, ANEIDES HARDII

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Sacramento Mountains Salamander (Aneides hardii) is a state-listed threatened species endemic to three mountain ranges in south central New Mexico. Information about the ecological requirements of this species is inadequate for managers to make informed conservation decisions, yet changes in ma...

  4. Conservation genetics of extremely isolated urban populations of the northern dusky salamander (Desmognathus fuscus) in New York City.

    PubMed

    Munshi-South, Jason; Zak, Yana; Pehek, Ellen

    2013-01-01

    Urbanization is a major cause of amphibian decline. Stream-dwelling plethodontid salamanders are particularly susceptible to urbanization due to declining water quality and hydrological changes, but few studies have examined these taxa in cities. The northern dusky salamander (Desmognathus fuscus) was once common in the New York City metropolitan area, but has substantially declined throughout the region in recent decades. We used five tetranucleotide microsatellite loci to examine population differentiation, genetic variation, and bottlenecks among five remnant urban populations of dusky salamanders in NYC. These genetic measures provide information on isolation, prevalence of inbreeding, long-term prospects for population persistence, and potential for evolutionary responses to future environmental change. All populations were genetically differentiated from each other, and the most isolated populations in Manhattan have maintained very little genetic variation (i.e. <20% heterozygosity). A majority of the populations also exhibited evidence of genetic bottlenecks. These findings contrast with published estimates of high genetic variation within and lack of structure between populations of other desmognathine salamanders sampled over similar or larger spatial scales. Declines in genetic variation likely resulted from population extirpations and the degradation of stream and terrestrial paths for dispersal in NYC. Loss of genetic variability in populations isolated by human development may be an underappreciated cause and/or consequence of the decline of this species in urbanized areas of the northeast USA. PMID:23646283

  5. Conservation genetics of extremely isolated urban populations of the northern dusky salamander (Desmognathus fuscus) in New York City

    PubMed Central

    Zak, Yana; Pehek, Ellen

    2013-01-01

    Urbanization is a major cause of amphibian decline. Stream-dwelling plethodontid salamanders are particularly susceptible to urbanization due to declining water quality and hydrological changes, but few studies have examined these taxa in cities. The northern dusky salamander (Desmognathus fuscus) was once common in the New York City metropolitan area, but has substantially declined throughout the region in recent decades. We used five tetranucleotide microsatellite loci to examine population differentiation, genetic variation, and bottlenecks among five remnant urban populations of dusky salamanders in NYC. These genetic measures provide information on isolation, prevalence of inbreeding, long-term prospects for population persistence, and potential for evolutionary responses to future environmental change. All populations were genetically differentiated from each other, and the most isolated populations in Manhattan have maintained very little genetic variation (i.e. <20% heterozygosity). A majority of the populations also exhibited evidence of genetic bottlenecks. These findings contrast with published estimates of high genetic variation within and lack of structure between populations of other desmognathine salamanders sampled over similar or larger spatial scales. Declines in genetic variation likely resulted from population extirpations and the degradation of stream and terrestrial paths for dispersal in NYC. Loss of genetic variability in populations isolated by human development may be an underappreciated cause and/or consequence of the decline of this species in urbanized areas of the northeast USA. PMID:23646283

  6. Feeding Preferences of the Larval Southern Two-Lined Salamander, Eurycea Cirrigera, in an Impacted Agricultural Area, Southwest Georgia.

    NASA Astrophysics Data System (ADS)

    Muenz, T. K.; Golladay, S. W.; Smith, L. L.; Vellidis, G.

    2005-05-01

    Feeding preference of the stream-dwelling Southern Two-lined Salamander, Eurycea cirrigera, was examined in streams affected by agricultural practices in southwest Georgia. Larvae were collected within bimonthly benthic macroinvertebrate samples from February 2002 to February 2003. Five stream reaches were sampled, two of which were fenced from cattle and three allowed cattle access. Forty larvae were recovered from the invertebrate collections, with significantly higher captures at fenced sites than unfenced sites. The entire digestive tract was removed from larvae and stomach contents were examined to better understand prey selection in streams with differing intensities of adjacent agricultural land-use. Invertebrates were enumerated in 34 salamander stomachs, with Chironomidae comprising the largest percentage of individuals found, both in stomach contents and habitat collections. Electivity values showed a wide range of variability among individual salamanders, however, overall indices suggest slight positive selection for a subfamily of the Chironomidae, the Tanypodinae. It appears that E.cirrigera larvae select for Tanypodinae, however, this invertebrate group was found at all stream sites, suggesting factors other than prey abundance, such as stream habitat quality, may also influence larval salamander abundance.

  7. Transcriptome analysis of the endangered Chinese giant salamander (Andrias davidianus): Immune modulation in response to Aeromonas hydrophila infection.

    PubMed

    Qi, Zhitao; Zhang, Qihuan; Wang, Zisheng; Ma, Tianyi; Zhou, Jie; Holland, Jason W; Gao, Qian

    2016-01-01

    The endangered Chinese giant salamander (Andrias davidianus) is the largest extant amphibian species. Disease outbreaks represent one of the major factors threatening A. davidianus populations in the wild and the viability of artificial breeding programmes. Development of future immune therapies to eliminate infectious disease in A. davidianus is dependent on a thorough understanding of the immune mechanisms elicited by pathogen encounters. To this end we have undertaken, for the first time in amphibians, differential transcriptome analysis of the giant salamander response to Aeromonas hydrophila, one of the most devastating pathogens affecting amphibian populations. Out of 87,204 non-redundant consensus unigenes 19,216 were annotated, 6834 of which were upregulated and 906 down-regulated following bacterial infection. 2058 unigenes were involved with immune system processes, including 287 differentially expressed unigenes indicative of the impact of bacterial infection on several innate and adaptive immune pathways in the giant salamander. Other pathways not directly associated with immune-related activity were differentially expressed, including developmental, structural, molecular and growth processes. Overall, this work provides valuable insights into the underlying immune mechanisms elicited during bacterial infection in amphibians that may aid in the future development of disease control measures in protecting the Chinese giant salamander. With the unique position of amphibians in the transition of tetrapods from aquatic to terrestrial habitats, our study will also be invaluable towards the further understanding of the evolution of tetrapod immunity. PMID:26620078

  8. Biodiversity of Costa Rican salamanders: Implications of high levels of genetic differentiation and phylogeographic structure for species formation

    PubMed Central

    García-París, Mario; Good, David A.; Parra-Olea, Gabriela; Wake, David B.

    2000-01-01

    Although salamanders are characteristic amphibians in Holarctic temperate habitats, in tropical regions they have diversified evolutionarily only in tropical America. An adaptive radiation centered in Middle America occurred late in the history of a single clade, the supergenus Bolitoglossa (Plethodontidae), and large numbers of species now occur in diverse habitats. Sublineages within this clade decrease in number from the northern to southern parts of Middle America, and in Costa Rica, there are but three. Despite this phylogenetic constraint, Costa Rica has many species; the number of salamander species on one local elevational transect in the Cordillera de Talamanca may be the largest for any such transect in the world. Extraordinary variation in sequences of the mitochondrial gene cytochrome b within a clade of the genus Bolitoglossa in Costa Rica reveals strong phylogeographic structure within a single species, Bolitoglossa pesrubra. Allozymic variation in 19 proteins reveals a pattern largely concordant with the mitochondrial DNA phylogeography. More species exist than are currently recognized. Diversification occurs in restricted geographic areas and involves sharp geographic and elevational differentiation and zonation. In their degree of genetic differentiation at a local scale, these species of the deep tropics exceed the known variation of extratropical salamanders, which also differ in being less restricted in elevational range. Salamanders display “tropicality” in that although speciose, they are usually local in distribution and rare. They display strong ecological and physiological differentiation that may contribute importantly to morphological divergence and species formation. PMID:10677512

  9. Computer-assisted photo identification outperforms visible implant elastomers in an endangered salamander, Eurycea tonkawae.

    PubMed

    Bendik, Nathan F; Morrison, Thomas A; Gluesenkamp, Andrew G; Sanders, Mark S; O'Donnell, Lisa J

    2013-01-01

    Despite recognition that nearly one-third of the 6300 amphibian species are threatened with extinction, our understanding of the general ecology and population status of many amphibians is relatively poor. A widely-used method for monitoring amphibians involves injecting captured individuals with unique combinations of colored visible implant elastomer (VIE). We compared VIE identification to a less-invasive method - computer-assisted photographic identification (photoID) - in endangered Jollyville Plateau salamanders (Eurycea tonkawae), a species with a known range limited to eight stream drainages in central Texas. We based photoID on the unique pigmentation patterns on the dorsal head region of 1215 individual salamanders using identification software Wild-ID. We compared the performance of photoID methods to VIEs using both 'high-quality' and 'low-quality' images, which were taken using two different camera types and technologies. For high-quality images, the photoID method had a false rejection rate of 0.76% compared to 1.90% for VIEs. Using a comparable dataset of lower-quality images, the false rejection rate was much higher (15.9%). Photo matching scores were negatively correlated with time between captures, suggesting that evolving natural marks could increase misidentification rates in longer term capture-recapture studies. Our study demonstrates the utility of large-scale capture-recapture using photo identification methods for Eurycea and other species with stable natural marks that can be reliably photographed. PMID:23555669

  10. Non-additive response of larval ringed salamanders to intraspecific density.

    PubMed

    Ousterhout, Brittany H; Semlitsch, Raymond D

    2016-04-01

    Conditions experienced in early developmental stages can have long-term consequences for individual fitness. High intraspecific density during the natal period can affect juvenile and eventually adult growth rates, metabolism, immune function, survival, and fecundity. Despite the important ecological and evolutionary effects of early developmental density, the form of the relationship between natal density and resulting juvenile phenotype is poorly understood. To test competing hypotheses explaining responses to intraspecific density, we experimentally manipulated the initial larval density of ringed salamanders (Ambystoma annulatum), a pond-breeding amphibian, over 11 densities. We modeled the functional form of the relationship between natal density and juvenile traits, and compared the relative support for the various hypotheses based on their goodness of fit. These functional form models were then used to parameterize a simple simulation model of population growth. Our data support non-additive density dependence and presents an alternate hypothesis to additive density dependence, self-thinning and Allee effects in larval amphibians. We posit that ringed salamander larvae may be under selective pressure for tolerance to high density and increased efficiency in resource utilization. Additionally, we demonstrate that models of population dynamics are sensitive to assumptions of the functional form of density dependence. PMID:26683834

  11. Purification and characterization of cholecystokinin from the skin of salamander Tylototriton verrucosus

    PubMed Central

    JIANG, Wen-Bin; HAKIM, Ma; LUO, Lei; LI, Bo-Wen; YANG, Shi-Long; SONG, Yu-Zhu; LAI, Ren; LU, Qiu-Min

    2015-01-01

    As a group of intestinal hormones and neurotransmitters, cholecystokinins (CCKs) regulate and affect pancreatic enzyme secretion, gastrointestinal motility, pain hypersensitivity, digestion and satiety, and generally contain a DYMGWMDFG sequence at the C-terminus. Many CCKs have been reported in mammals. However, only a few have been reported in amphibians, such as Hyla nigrovittata, Xenopus laevis, and Rana catesbeiana, with none reported in urodele amphibians like newts and salamanders. Here, a CCK called CCK-TV was identified and characterized from the skin of the salamander Tylototriton verrucosus. This CCK contained an amino acid sequence of DYMGWMDF-NH2 as seen in other CCKs. A cDNA encoding the CCK precursor containing 129 amino acid residues was cloned from the cDNA library of T. verrucosus skin. The CCK-TV had the potential to induce the contraction of smooth muscle strips isolated from porcine gallbladder, eliciting contraction at a concentration of 5.0x10-11 mol/L and inducing maximal contraction at a concentration of 2.0x10-6 mol/L. The EC50 was 13.6 nmol/L. To the best of our knowledge, this is the first report to identify the presence of a CCK in an urodele amphibian. PMID:26018861

  12. Coalescence patterns of endemic Tibetan species of stream salamanders (Hynobiidae: Batrachuperus).

    PubMed

    Lu, Bin; Zheng, Yuchi; Murphy, Robert W; Zeng, Xiaomao

    2012-07-01

    Orogenesis of topographically diverse montane regions often drives complex evolutionary histories of species. The extensive biodiversity of the eastern edge of the Tibetan Plateau, which gradually decreases eastwardly, facilitates a comparison of historical patterns. We use coalescence methods to compare species of stream salamanders (Batrachuperus) that occur at high and low elevations. Coalescent simulations reveal that closely related species are likely to have been influenced by different drivers of diversification. Species living in the western high-elevation region with its northsouth extending mountains appear to have experienced colonization via dispersal followed by isolation and divergence. In contrast, species on the eastern low-elevation region, which has many discontinuous mountain ranges, appear to have experienced fragmentation, sometimes staged, of wide-ranging ancestral populations. The two groups of species appear to have been affected differently by glaciation. High-elevation species, which are more resistant to cooler temperatures, appear to have experienced population declines as recently as the last glaciation (0.016-0.032Ma). In contrast, salamanders dwelling in the warmer and wetter habitats at low-elevation environs appear to have been affected less by the relatively recent, milder glaciation, and more so by harsher, extensive glaciations (0.5-0.175 Ma). Thus, elevation, topography and cold tolerance appear to drive evolutionary patterns of diversification and demography even among closely related taxa. The comparison of multiple species in genealogical analyses can lead to an understanding of the evolutionary drivers. PMID:22571598

  13. Side-by-side secretion of Late Palaeozoic diverged courtship pheromones in an aquatic salamander.

    PubMed

    Van Bocxlaer, Ines; Treer, Dag; Maex, Margo; Vandebergh, Wim; Janssenswillen, Sunita; Stegen, Gwij; Kok, Philippe; Willaert, Bert; Matthijs, Severine; Martens, Erik; Mortier, Anneleen; de Greve, Henri; Proost, Paul; Bossuyt, Franky

    2015-03-22

    Males of the advanced salamanders (Salamandroidea) attain internal fertilization without a copulatory organ by depositing a spermatophore on the substrate in the environment, which females subsequently take up with their cloaca. The aquatically reproducing modern Eurasian newts (Salamandridae) have taken this to extremes, because most species do not display close physical contact during courtship, but instead largely rely on females following the male track at spermatophore deposition. Although pheromones have been widely assumed to represent an important aspect of male courtship, molecules able to induce the female following behaviour that is the prelude for successful insemination have not yet been identified. Here, we show that uncleaved sodefrin precursor-like factor (SPF) protein pheromones are sufficient to elicit such behaviour in female palmate newts (Lissotriton helveticus). Combined transcriptomic and proteomic evidence shows that males simultaneously tail-fan multiple ca 20 kDa glycosylated SPF proteins during courtship. Notably, molecular dating estimates show that the diversification of these proteins already started in the late Palaeozoic, about 300 million years ago. Our study thus not only extends the use of uncleaved SPF proteins outside terrestrially reproducing plethodontid salamanders, but also reveals one of the oldest vertebrate pheromone systems. PMID:25694622

  14. Estimating site occupancy and species detection probability parameters for terrestrial salamanders

    USGS Publications Warehouse

    Bailey, L.L.; Simons, T.R.; Pollock, K.H.

    2004-01-01

    Recent, worldwide amphibian declines have highlighted a need for more extensive and rigorous monitoring programs to document species occurrence and detect population change. Abundance estimation methods, such as mark-recapture, are often expensive and impractical for large-scale or long-term amphibian monitoring. We apply a new method to estimate proportion of area occupied using detection/nondetection data from a terrestrial salamander system in Great Smoky Mountains National Park. Estimated species-specific detection probabilities were all <1 and varied among seven species and four sampling methods. Time (i.e., sampling occasion) and four large-scale habitat characteristics (previous disturbance history, vegetation type, elevation, and stream presence) were important covariates in estimates of both proportion of area occupied and detection probability. All sampling methods were consistent in their ability to identify important covariates for each salamander species. We believe proportion of area occupied represents a useful state variable for large-scale monitoring programs. However, our results emphasize the importance of estimating detection and occupancy probabilities rather than using an unadjusted proportion of sites where species are observed where actual occupancy probabilities are confounded with detection probabilities. Estimated detection probabilities accommodate variations in sampling effort; thus comparisons of occupancy probabilities are possible among studies with different sampling protocols.

  15. Cutaneous mastocytomas in the neotenic caudate amphibians Ambystoma mexicanum (axolotl) and Ambystoma tigrinun (tiger salamander)

    USGS Publications Warehouse

    Harshbarger, J.C.; Chang, S.C.; DeLanney, L.E.; Rose, F.L.; Green, D.E.

    1999-01-01

    Spontaneous mastocytomas studied in 18 axolotls (Ambystoma mexicanum) and six tiger salamanders (Ambystoma tigrinum) were gray-white, uni- to multilobular cutaneous protrusions from 2mm to 2cm in diameter. Tumors were moderately cellular unencapsulated masses that usually infiltrated the dermis and hypodermis with the destruction of intervening tissues. Some tumors were invading superficial bundles of the underlying skeletal muscle. Tumors consisted of mitotically active cells derived from a single lineage but showing a range of differentiation. Immature cells had nearly smooth to lightly cleft or folded basophilic nuclei bordered by a band of cytoplasm with few cytoplasmic processes and containing a few small uniform eccentric granules. Mature cells had basophilic nuclei with deep clefts or folds and abundant eosinophilic cytoplasm with multiple long intertwining cytoplasmic extensions packed with metachromatic granules. The axolotls were old individuals from an inbred laboratory colony. The tiger salamanders were wild animals from a single polluted pond. They could have been old and inbred. Both groups were neotenic. These are the first mastocytomas discovered in cold-blooded animals.

  16. Successful treatment of Batrachochytrium salamandrivorans infections in salamanders requires synergy between voriconazole, polymyxin E and temperature

    PubMed Central

    Blooi, M.; Pasmans, F.; Rouffaer, L.; Haesebrouck, F.; Vercammen, F.; Martel, A.

    2015-01-01

    Chytridiomycosis caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) poses a serious threat to urodelan diversity worldwide. Antimycotic treatment of this disease using protocols developed for the related fungus Batrachochytrium dendrobatidis (Bd), results in therapeutic failure. Here, we reveal that this therapeutic failure is partly due to different minimum inhibitory concentrations (MICs) of antimycotics against Bsal and Bd. In vitro growth inhibition of Bsal occurs after exposure to voriconazole, polymyxin E, itraconazole and terbinafine but not to florfenicol. Synergistic effects between polymyxin E and voriconazole or itraconazole significantly decreased the combined MICs necessary to inhibit Bsal growth. Topical treatment of infected fire salamanders (Salamandra salamandra), with voriconazole or itraconazole alone (12.5 μg/ml and 0.6 μg/ml respectively) or in combination with polymyxin E (2000 IU/ml) at an ambient temperature of 15 °C during 10 days decreased fungal loads but did not clear Bsal infections. However, topical treatment of Bsal infected animals with a combination of polymyxin E (2000 IU/ml) and voriconazole (12.5 μg/ml) at an ambient temperature of 20 °C resulted in clearance of Bsal infections. This treatment protocol was validated in 12 fire salamanders infected with Bsal during a field outbreak and resulted in clearance of infection in all animals. PMID:26123899

  17. Successful treatment of Batrachochytrium salamandrivorans infections in salamanders requires synergy between voriconazole, polymyxin E and temperature.

    PubMed

    Blooi, M; Pasmans, F; Rouffaer, L; Haesebrouck, F; Vercammen, F; Martel, A

    2015-01-01

    Chytridiomycosis caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) poses a serious threat to urodelan diversity worldwide. Antimycotic treatment of this disease using protocols developed for the related fungus Batrachochytrium dendrobatidis (Bd), results in therapeutic failure. Here, we reveal that this therapeutic failure is partly due to different minimum inhibitory concentrations (MICs) of antimycotics against Bsal and Bd. In vitro growth inhibition of Bsal occurs after exposure to voriconazole, polymyxin E, itraconazole and terbinafine but not to florfenicol. Synergistic effects between polymyxin E and voriconazole or itraconazole significantly decreased the combined MICs necessary to inhibit Bsal growth. Topical treatment of infected fire salamanders (Salamandra salamandra), with voriconazole or itraconazole alone (12.5 μg/ml and 0.6 μg/ml respectively) or in combination with polymyxin E (2000 IU/ml) at an ambient temperature of 15 °C during 10 days decreased fungal loads but did not clear Bsal infections. However, topical treatment of Bsal infected animals with a combination of polymyxin E (2000 IU/ml) and voriconazole (12.5 μg/ml) at an ambient temperature of 20 °C resulted in clearance of Bsal infections. This treatment protocol was validated in 12 fire salamanders infected with Bsal during a field outbreak and resulted in clearance of infection in all animals. PMID:26123899

  18. Avian, salamander, and forest floor mercury concentrations increase with elevation in a terrestrial ecosystem.

    PubMed

    Townsend, Jason M; Driscoll, Charles T; Rimmer, Christopher C; McFarland, Kent P

    2014-01-01

    High-elevation ecosystems of the northeastern United States are vulnerable to deposition and environmental accumulation of atmospheric pollutants, yet little work has been done to assess mercury (Hg) concentrations in organisms occupying montane ecosystems. The authors present data on Hg concentrations in ground-foraging insectivorous songbirds, a terrestrial salamander, and forest floor horizons sampled along a forested elevational gradient from 185 m to 1273 m in the Catskill Mountains, New York, USA. Mean Hg concentrations in Catharus thrushes and the salamander Plethodon cinereus increased with elevation, as did Hg concentrations in all forest floor horizons. Mean Hg concentrations in organic soils at approximately 1200 m elevation (503.5 ± 17.7 ng/g, dry wt) were 4.4-fold greater than those at approximately 200 m. Montane ecosystems of the northeastern United States, and probably elsewhere, are exposed to higher levels of atmospheric Hg deposition as reflected in accumulation patterns in the forest floor and associated high-elevation fauna. This information can be used to parameterize and test Hg transport and bioaccumulation models of landscape-specific patterns and may serve as a monitoring tool for decision makers considering future controls on Hg emissions. Further investigation is needed into the potential effects of increased Hg concentrations on high-elevation fauna. PMID:24302165

  19. Spatial genetic structure and regional demography in the southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, Mark P.; Haig, Susan M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders.

  20. Phylogeography and spatial genetic structure of the Southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, M.P.; Haig, S.M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders. ?? The American Genetic Association. 2006. All rights reserved.

  1. Purification and characterization of cholecystokinin from the skin of salamander Tylototriton verrucosus.

    PubMed

    Jiang, Wen-Bin; Hakim, Ma; Luo, Lei; Li, Bo-Wen; Yang, Shi-Long; Song, Yu-Zhu; Lai, Ren; Lu, Qiu-Min

    2015-05-18

    As a group of intestinal hormones and neurotransmitters, cholecystokinins (CCKs) regulate and affect pancreatic enzyme secretion, gastrointestinal motility, pain hypersensitivity, digestion and satiety, and generally contain a DYMGWMDFG sequence at the C-terminus. Many CCKs have been reported in mammals. However, only a few have been reported in amphibians, such as Hyla nigrovittata, Xenopus laevis, and Rana catesbeiana, with none reported in urodele amphibians like newts and salamanders. Here, a CCK called CCK-TV was identified and characterized from the skin of the salamander Tylototriton verrucosus. This CCK contained an amino acid sequence of DYMGWMDF-NH2 as seen in other CCKs. A cDNA encoding the CCK precursor containing 129 amino acid residues was cloned from the cDNA library of T. verrucosus skin. The CCK-TV had the potential to induce the contraction of smooth muscle strips isolated from porcine gallbladder, eliciting contraction at a concentration of 5.0 x 10⁻¹¹ mol/L and inducing maximal contraction at a concentration of 2.0 x 10⁻⁶ mol/L. The EC50 was 13.6 nmol/L. To the best of our knowledge, this is the first report to identify the presence of a CCK in an urodele amphibian. PMID:26018861

  2. Cold-blooded snipers: thermal independence of ballistic tongue projection in the salamander Hydromantes platycephalus.

    PubMed

    Deban, Stephen M; Richardson, Jason C

    2011-12-01

    Plethodontid salamanders of the genus Hydromantes capture prey using the most extreme tongue projection among salamanders, and can shoot the tongue a distance of 80% of body length in less than 20 msec. The tongue skeleton is projected from the body via an elastic-recoil mechanism that decouples muscle contraction from tongue projection, amplifying muscle power tenfold. We tested the hypothesis that the elastic-recoil mechanism also endows tongue projection with low thermal dependence by examining the kinematics and dynamics of tongue projection in Hydromantes platycephalus over a range of body temperatures (2-24°C). We found that H. platycephalus maintained tongue-projection performance over the tested temperature range and that tongue projection showed thermal independence (Q(10) values of 0.94-1.04) of all performance parameters including projection distance, average velocity, and peak instantaneous values of velocity, acceleration, and power. Nonelastic, muscle-powered tongue retraction, in contrast, responded to temperature changes significantly differently than elastic tongue projection; performance parameters of retraction displayed thermal dependence typical of muscle-powered movement (Q(10) values of 1.63-4.97). These results reveal that the elastic-recoil mechanism liberates tongue projection from the effects of temperature on muscle contractile rates. We suggest that relative thermal independence is a general characteristic of elastic-recoil mechanisms and may promote the evolution of these mechanisms in ectothermic animals. PMID:21953778

  3. Phenotypic variation in metamorphosis and paedomorphosis in the salamander Ambystoma talpoideum

    SciTech Connect

    Semlitsch, R.D.; Gibbons, J.W.

    1985-08-01

    Phenotypic variation in metamorphosis and paedomorphosis in the salamander Ambystoma talpoideum was examined to determine its environmental or genetic basis. Eight artificial ponds were maintained, four at each of two environmental treatments: constant water level, to simulate fish-free permanent breeding ponds, and gradual drying out, to simulate temporary breeding ponds. Two populations of salamanders were used, derived from two breeding ponds having different frequencies of paedomorphosis. The water level in the drying treatment was lowered during the last 10 wk of the experimental period with no apparent differences in water chemistry parameters between treatments and only a slight change in water temperature during the last 2 wk. The effects of water level were potentially confounded by those of water temperature, density of larvae, and amount food. Population differences in the frequency of metamorphosis and paedomorphosis could potentially represent genetic differences resulting from the different selective regimes that individuals encounter in breeding ponds varying in drying frequency. 35 references, 3 figures, 4 tables.

  4. Reduced genetic variation in the Japanese giant salamander, Andrias japonicus (Amphibia: Caudata).

    PubMed

    Matsui, Masafumi; Tominaga, Atsushi; Liu, Wan-zhao; Tanaka-Ueno, Tomoko

    2008-10-01

    The phylogenetic relationships among 46 samples from 27 populations of the Japanese giant salamander, Andriasjaponicus and its congener, A. davidianus from China was investigated, using 3664 bp sequences of the mitochondrial genes NADH1, NADH3, cyt b and CR, partial NADH6 and intervening genes. In phylogenetic trees constructed by MP, ML, and Bayesian methods, the family Cryptobranchidae and the genus Andrias both form monophyletic groups. Japanese A. japonicus and Chinese A. davidianus are sister taxa and can be regarded as separate species despite a small degree of genetic differentiation. Andriasjaponicus is divided into central and western clades, but the phylogenetic relationships within the latter clade are unresolved. As previously reported from allozyme analyses, A. japonicus exhibits little genetic differentiation, in strong contrast to salamanders of the genus Hynobius with which their distributions overlap. This reduced genetic variability in A. japonicus is attributable to a unique mating system of polygyny, delayed sexual maturity, notable longevity, life in a stable aquatic environment, and gigantism, as well as bottleneck effects following habitat fragmentation and extinction of local populations during Quaternary glaciations. The species is thus susceptible to extinction by potential environmental fluctuations, and requires extensive conservation measures. PMID:18723097

  5. Computer-Assisted Photo Identification Outperforms Visible Implant Elastomers in an Endangered Salamander, Eurycea tonkawae

    PubMed Central

    Bendik, Nathan F.; Morrison, Thomas A.; Gluesenkamp, Andrew G.; Sanders, Mark S.; O’Donnell, Lisa J.

    2013-01-01

    Despite recognition that nearly one-third of the 6300 amphibian species are threatened with extinction, our understanding of the general ecology and population status of many amphibians is relatively poor. A widely-used method for monitoring amphibians involves injecting captured individuals with unique combinations of colored visible implant elastomer (VIE). We compared VIE identification to a less-invasive method – computer-assisted photographic identification (photoID) – in endangered Jollyville Plateau salamanders (Eurycea tonkawae), a species with a known range limited to eight stream drainages in central Texas. We based photoID on the unique pigmentation patterns on the dorsal head region of 1215 individual salamanders using identification software Wild-ID. We compared the performance of photoID methods to VIEs using both ‘high-quality’ and ‘low-quality’ images, which were taken using two different camera types and technologies. For high-quality images, the photoID method had a false rejection rate of 0.76% compared to 1.90% for VIEs. Using a comparable dataset of lower-quality images, the false rejection rate was much higher (15.9%). Photo matching scores were negatively correlated with time between captures, suggesting that evolving natural marks could increase misidentification rates in longer term capture-recapture studies. Our study demonstrates the utility of large-scale capture-recapture using photo identification methods for Eurycea and other species with stable natural marks that can be reliably photographed. PMID:23555669

  6. Tuataras and salamanders show that walking and running mechanics are ancient features of tetrapod locomotion

    PubMed Central

    Reilly, Stephen M; McElroy, Eric J; Andrew Odum, R; Hornyak, Valerie A

    2006-01-01

    The lumbering locomotor behaviours of tuataras and salamanders are the best examples of quadrupedal locomotion of early terrestrial vertebrates. We show they use the same walking (out-of-phase) and running (in-phase) patterns of external mechanical energy fluctuations of the centre-of-mass known in fast moving (cursorial) animals. Thus, walking and running centre-of-mass mechanics have been a feature of tetrapods since quadrupedal locomotion emerged over 400 million years ago. When walking, these sprawling animals save external mechanical energy with the same pendular effectiveness observed in cursorial animals. However, unlike cursorial animals (that change footfall patterns and mechanics with speed), tuataras and salamanders use only diagonal couplet gaits and indifferently change from walking to running mechanics with no significant change in total mechanical energy. Thus, the change from walking to running is not related to speed and the advantage of walking versus running is unclear. Furthermore, lumbering mechanics in primitive tetrapods is reflected in having total mechanical energy driven by potential energy (rather than kinetic energy as in cursorial animals) and relative centre-of-mass displacements an order of magnitude greater than cursorial animals. Thus, large vertical displacements associated with lumbering locomotion in primitive tetrapods may preclude their ability to increase speed. PMID:16777753

  7. Complete nucleotide sequence of the mitochondrial genome of a salamander, Mertensiella luschani.

    PubMed

    Zardoya, Rafael; Malaga-Trillo, Edward; Veith, Michael; Meyer, Axel

    2003-10-23

    The complete nucleotide sequence (16,650 bp) of the mitochondrial genome of the salamander Mertensiella luschani (Caudata, Amphibia) was determined. This molecule conforms to the consensus vertebrate mitochondrial gene order. However, it is characterized by a long non-coding intervening sequence with two 124-bp repeats between the tRNA(Thr) and tRNA(Pro) genes. The new sequence data were used to reconstruct a phylogeny of jawed vertebrates. Phylogenetic analyses of all mitochondrial protein-coding genes at the amino acid level recovered a robust vertebrate tree in which lungfishes are the closest living relatives of tetrapods, salamanders and frogs are grouped together to the exclusion of caecilians (the Batrachia hypothesis) in a monophyletic amphibian clade, turtles show diapsid affinities and are placed as sister group of crocodiles+birds, and the marsupials are grouped together with monotremes and basal to placental mammals. The deduced phylogeny was used to characterize the molecular evolution of vertebrate mitochondrial proteins. Amino acid frequencies were analyzed across the main lineages of jawed vertebrates, and leucine and cysteine were found to be the most and least abundant amino acids in mitochondrial proteins, respectively. Patterns of amino acid replacements were conserved among vertebrates. Overall, cartilaginous fishes showed the least variation in amino acid frequencies and replacements. Constancy of rates of evolution among the main lineages of jawed vertebrates was rejected. PMID:14604788

  8. Enlarged Multilocus Data set Provides Surprisingly Younger Time of Origin for the Plethodontidae, the Largest Family of Salamanders.

    PubMed

    Shen, Xing-Xing; Liang, Dan; Chen, Meng-Yun; Mao, Rong-Li; Wake, David B; Zhang, Peng

    2016-01-01

    Deep phylogenetic relationships of the largest salamander family Plethodontidae have been difficult to resolve, probably reflecting a rapid diversification early in their evolutionary history. Here, data from 50 independent nuclear markers (total 48,582 bp) are used to reconstruct the phylogeny and divergence times for plethodontid salamanders, using both concatenation and coalescence-based species tree analyses. Our results robustly resolve the position of the enigmatic eastern North American four-toed salamander (Hemidactylium) as the sister taxon of Batrachoseps + Tribe Bolitoglossini, thus settling a long-standing question. Furthermore, we statistically reject sister taxon status of Karsenia and Hydromantes, the only plethodontids to occur outside the Americas, leading us to new biogeographic hypotheses. Contrary to previous long-standing arguments that plethodontid salamanders are an old lineage originating in the Cretaceous (more than 90 Ma), our analyses lead to the hypothesis that these salamanders are much younger, arising close to the K-T boundary (~66 Ma). These time estimates are highly stable using alternative calibration schemes and dating methods. Our data simulation highlights the potential risk of making strong arguments about phylogenetic timing based on inferences from a handful of nuclear genes, a common practice. Based on the newly obtained timetree and ancestral area reconstruction results, we argue that (i) the classic "Out of Appalachia" hypothesis of plethodontid origins is problematic; (ii) the common ancestor of extant plethodontids may have originated in northwestern North America in the early Paleocene; (iii) origins of Eurasian plethodontids likely result from two separate dispersal events from western North America via Beringia in the late Eocene (~42 Ma) and the early Miocene (~23 Ma), respectively. PMID:26385618

  9. New Morbidity: Implications for Prevention of Children's Disabilities.

    ERIC Educational Resources Information Center

    Baumeister, Alfred A.; And Others

    1990-01-01

    This article identifies and analyzes specific environmental, psychosocial, and economic factors adversely affecting childrens' well-being. Contemporary outcomes, including adolescent homicide and suicide, substance abuse, sexually transmitted diseases, developmental exceptionalities, and other health hazards, are considered. Adolescent pregnancy,…

  10. Psychiatric Morbidity of Cannabis Abuse

    PubMed Central

    Sarkar, Jaydip; Murthy, Pratima; Singh, Swaran P

    2003-01-01

    The paper evaluates the hypothesis that cannabis abuse is associated with a broad range of psychiatric disorders in India, an area with relatively high prevalence of cannabis use. Retrospective case-note review of all cases with cannabis related diagnosis over a 11 -year period, for subjects presenting to a tertiary psychiatric hospital in southern India was carried out. Information pertaining to sociodemographic, personal, social, substance-use related, psychiatric and treatment histories, was gathered. Standardized diagnoses were made according to Diagnostic Criteria for Research of the World Health Organization, on the basis of information available. Cannabis abuse is associated with widespread psychiatric morbidity that spans the major categories of mental disorders under the ICD-10 system, although proportion of patients with psychotic disorders far outweighed those with non-psychotic disorders. Whilst paranoid psychoses were more prevalent, a significant number of patients with affective psychoses, particularly mania, was also noted. Besides being known as either the causative agent or a potent risk factor in cases of paranoid psychoses, cannabis appears to have similar capabilities with regard to affective psychoses, particularly in cases of mania. It is suggested that cannabis has the potential to act as a "life event stressor" amongst subjects vulnerable to develop affective psychoses and the possible aetiopathogenesis of such a finding is discussed. PMID:21206852

  11. Lateral sacral imaging in the morbidly obese.

    PubMed

    Miller, Anna N; Krieg, James C; Chip Routt, Milton L

    2013-05-01

    Obesity can complicate surgical procedures by both adding to difficulty intraoperatively and increasing postoperative complications. Intraoperative imaging can be difficult on morbidly obese patients. We have noted specifically that in morbidly obese patients where the lateral sacrum cannot be visualized on the pre-operative scout computed tomography image, the lateral sacrum will not be able to be seen on intraoperative fluoroscopy. This is an important component of preoperative planning in morbidly obese patients with pelvic ring injuries. PMID:22648043

  12. Can the eastern red-backed salamander (Plethodon cinereus) persist in an acidified landscape?

    USGS Publications Warehouse

    Bondi, Cheryl A; Beier, Colin M.; Ducey, Peter K; Lawrence, Gregory B.; Bailey, Scott W.

    2016-01-01

    Hardwood forests of eastern North America have experienced decades of acidic deposition, leading to soil acidification where base cation supply was insufficient to neutralize acid inputs. Negative impacts of soil acidity on amphibians include disrupted embryonic development, lower growth rates, and habitat loss. However, some amphibians exhibit intraspecific variation in acid tolerance, suggesting the potential for local adaptation in areas where soils are naturally acidic. The eastern red-backed salamander (Plethodon cinereus) is a highly abundant top predator of the northern hardwood forest floor. Early research found that P. cinereus was sensitive to acidic soils, avoiding substrates with pH < 3.8 and experiencing decreased growth rates in acidic habitats. However, recent studies have documented P. cinereus populations in lower pH conditions than previously observed, suggesting some populations may persist in acidic conditions. Here, we evaluated relationships between organic horizon soil pH and P. cinereus abundance, adult health (body size and condition), and microhabitat selection, based on surveys of 34 hardwood forests in northeastern United States that encompass a regional soil pH gradient. We found no associations between soil pH and P. cinereus abundance or health, and observed that this salamander used substrates with pH similar to that available, suggesting that pH does not mediate their fine-scale distributions. The strongest negative predictor of P. cinereus abundance was the presence of dusky salamanders (Desmognathus spp.), which were most abundant in the western Adirondacks. Our results indicate that P. cinereus occupies a wider range of soil pH than has been previously thought, which has implications for their functional role in forest food webs and nutrient cycles in acid-impaired ecosystems. Tolerance of P. cinereus for more acidic habitats, including anthropogenically acidified forests, may be due to local adaptation in

  13. Distribution and Abundance of California Giant Salamander (Dicamptodon ensatus) and Signal Crayfish (Pacifastacus leniusculus) in the Upper Redwood Creek Watershed, Marin County, California

    USGS Publications Warehouse

    Fong, Darren; Howell, Judd A.

    2006-01-01

    A survey was conducted in 1997-1998 to identify the distribution of non-native signal crayfish (Pacifastacus leniusculus) and larval California giant salamanders (Dicamptodon ensatus) within the upper Redwood Creek watershed (Marin County, California). The crayfish is widely distributed along the mainstem Redwood Creek. It was found in lower Fern Creek but not in any first order tributaries or above fish barriers. While present throughout the study area, larval California giant salamanders were found mainly in small headwater tributaries. Larval salamanders appear to use habitats in accordance to their availability, while signal crayfish were rarely found in shallow water habitats and appeared to prefer scour pools. Evidence of predation by signal crayfish on larval giant salamanders was found under confined conditions. Controlled laboratory and field experiments would be needed to determine whether competitive exclusion is occurring. Because of its widespread occurrence in the headwater streams surveyed in this project, California giant salamanders would be an appropriate indicator species for those interested in monitoring the health of small headwater streams. Future long-term monitoring using California giant salamanders should be based on permanent monitoring reaches with periodic basinwide habitat and animal surveys to determine if reaches are representative of basinwide conditions.

  14. Early child health in Lahore, Pakistan: VI. Morbidity.

    PubMed

    Zaman, S; Jalil, F; Karlberg, J; Hanson, L A

    1993-08-01

    Morbidity patterns were studied according to the age, area of living, sex and season among 1476 monthly followed infants born during 1984-1987 in four socio-economically different areas in Lahore, Pakistan. Infections were responsible for 87.0% of the morbidity during the first two years of life. The overall monthly based morbidity was 77.0% between birth and 24 months of age; diarrhoeal diseases 30.3%, upper and lower acute respiratory tract infections (ARI) 22.4%, skin and eye infections 6.7% and skin rash 6.2%. The vaccine-preventable diseases were only 0.5% of the total. Anaemia and rickets were rare (2.0%), but commonly seen among the nutritional deficiencies. Diarrhoea, tetanus, septicaemia, ARI and infections of the skin and eyes were reported more during earlier ages and from the three poorer areas of living. Diarrhoeal diseases, respiratory tract, skin and eye infections, in particular, followed clear seasonal patterns, while scabies prevailed throughout the year. The presence of these many preventable infections and illnesses implies that proper planning of interventions must be forthcoming. PMID:8219468

  15. [Occupational morbidity of railway transport workers].

    PubMed

    Karetskaia, T D; Pfaf, V F; Chernov, O E

    2015-01-01

    The authors present results of medical social monitoring of occupationalhazards that are the most prevalent in railway occupations workers, statistic data on occupational morbidity of railway transport workers over last 10 years. The article covers major causes of unfavorable effects resulting from occupational hazards in various workers categories. Dynamics of occupational morbidity parameters and its structure concerning separate nosologic entities are analyzed. PMID:25826875

  16. Effects of structural complexity enhancement on eastern red-backed salamander (Plethodon cinereus) populations in northern hardwood forests

    USGS Publications Warehouse

    McKenny, H.C.; Keeton, W.S.; Donovan, T.M.

    2006-01-01

    Managing for stand structural complexity in northern hardwood forests has been proposed as a method for promoting microhabitat characteristics important to eastern red-backed salamanders (Plethodon cinereus). We evaluated the effects of alternate, structure-based silvicultural systems on red-backed salamander populations at two research sites in northwestern Vermont. Treatments included two uneven-aged approaches (single-tree selection and group-selection) and one unconventional approach, termed "structural complexity enhancement" (SCE), that promotes development of late-successional structure, including elevated levels of coarse woody debris (CWD). Treatments were applied to 2 ha units and were replicated two to four times depending on treatment. We surveyed red-backed salamanders with a natural cover search method of transects nested within vegetation plots 1 year after logging. Abundance estimates corrected for detection probability were calculated from survey data with a binomial mixture model. Abundance estimates differed between study areas and were influenced by forest structural characteristics. Model selection was conducted using Akaike Information Criteria, corrected for over-dispersed data and small sample size (QAICc). We found no difference in abundance as a response to treatment as a whole, suggesting that all of the uneven-aged silvicultural systems evaluated can maintain salamander populations after harvest. However, abundance was tied to specific structural habitat attributes associated with study plots within treatments. The most parsimonious model of habitat covariates included site, relative density of overstory trees, and density of more-decayed and less-decayed downed CWD. Abundance responded positively to the density of downed, well-decayed CWD and negatively to the density of poorly decayed CWD and to overstory relative density. CWD volume was not a strong predictor of salamander abundance. We conclude that structural complexity enhancement

  17. Propulsive forces of mudskipper fins and salamander limbs during terrestrial locomotion: implications for the invasion of land.

    PubMed

    Kawano, Sandy M; Blob, Richard W

    2013-08-01

    The invasion of land was a pivotal event in vertebrate evolution that was associated with major appendicular modifications. Although fossils indicate that the evolution of fundamentally limb-like appendages likely occurred in aquatic environments, the functional consequences of using early digited limbs, rather than fins, for terrestrial propulsion have had little empirical investigation. Paleontological and experimental analyses both have led to the proposal of an early origin of "hind limb-driven" locomotion among tetrapods or their ancestors. However, the retention of a pectoral appendage that had already developed terrestrial adaptations has been proposed for some taxa, and few data are available from extant functional models that can provide a foundation for evaluating the relative contributions of pectoral and pelvic appendages to terrestrial support among early stem tetrapods. To examine these aspects of vertebrate locomotor evolution during the invasion of land, we measured three-dimensional ground reaction forces (GRFs) produced by isolated pectoral fins of mudskipper fishes (Periophthalmus barbarus) during terrestrial crutching, and compared these to isolated walking footfalls by the forelimbs and hind limbs of tiger salamanders (Ambystoma tigrinum), a species with subequally-sized limbs that facilitate comparisons to early tetrapods. Pectoral appendages of salamanders and mudskippers exhibited numerous differences in GRFs. Compared with salamander forelimbs, isolated fins of mudskippers bear lower vertical magnitudes of GRFs (as a proportion of body weight), and had GRFs that were oriented more medially. Comparing the salamanders' forelimbs and hind limbs, although the peak net GRF occurs later in stance for the forelimb, both limbs experience nearly identical mediolateral and vertical components of GRF, suggesting comparable contributions to support. Thus, forelimbs could also have played a significant locomotor role among basal tetrapods that had limbs

  18. Analysis of climatic factors influencing migrations of the salamander Ambystoma talpoideum

    SciTech Connect

    Semlitsch, R.D.

    1985-01-01

    Migrations of breeding adult and metamorphosing juvenile mole salamanders, Ambystoma talpoideum, were studied in five populations in South Carolina from September 1978 through July 1982. Onset of breeding immigrations occurred as early as September but migrations ''en masse'' did not occur until November, December, or January. Time of peak migration varied annually depending upon meteorological conditions. Total number of breeding adults or breeding population size, was significantly correlated with cumulative rainfall during the time of immigration. Sex ratio of immigrating adults was significantly biased towards males at the beginning of the breeding season whereas by the end of the season it was biased towards females. During the very dry year of 1980 - 1981 water levels in two relatively permanent breeding sites were substantially metamorphosis and emigration of sexually mature gilled morphs. Statistical models which predict the magnitude of migrations indicated that rainfall, water level, and minimum air temperature were consistently important environmental variables.

  19. Population genetic structure of critically endangered salamander (Hynobius amjiensis) in China: recommendations for conservation.

    PubMed

    Yang, J; Chen, C S; Chen, S H; Ding, P; Fan, Z Y; Lu, Y W; Yu, L P; Lin, H D

    2016-01-01

    Amji's salamander (Hynobius amjiensis) is a critically endangered species (IUCN Red List), which is endemic to mainland China. In the present study, five haplotypes were genotyped for the mtDNA cyt b gene in 45 specimens from three populations. Relatively low levels of haplotype diversity (h = 0.524) and nucleotide diversity (π = 0.00532) were detected. Analyses of the phylogenic structure of H. amjiensis showed no evidence of major geographic partitions or substantial barriers to historical gene flow throughout the species' range. Two major phylogenetic haplotype groups were revealed, and were estimated to have diverged about 1.262 million years ago. Mismatch distribution analysis, neutrality tests, and Bayesian skyline plots revealed no evidence of dramatic changes in the effective population size. According to the SAMOVA and STRUCTURE analyses, H. amjiensis should be regarded as two different management units. PMID:27323156

  20. Population Structure and Evolution after Speciation of the Hokkaido Salamander (Hynobius retardatus)

    PubMed Central

    Matsunami, Masatoshi; Igawa, Takeshi; Michimae, Hirofumi; Miura, Toru; Nishimura, Kinya

    2016-01-01

    The Hokkaido salamander (Hynobius retardatus) is endemic to Hokkaido Island, Japan, and shows intriguing flexible phenotypic plasticity and regional morphological diversity. However, to date, allozymes and partial mitochondria DNA sequences have provided only an outline of its demographic histories and the pattern of its genetic diversification. To understand the finer details of the population structure of this species and its evolution since speciation, we genotyped five regional populations by using 12 recently developed microsatellite polymorphic markers. We found a clear population structure with low gene flow among the five populations, but a close genetic relationship between the Teshio and Kitami populations. Our demographic analysis suggested that Teshio and Erimo had the largest effective population sizes among the five populations. These findings regarding the population structure and demography of H. retardatus improve our understanding of the faunal phylogeography on Hokkaido Island and also provide fundamental genetic information that will be useful for future studies. PMID:27257807

  1. Low pH effects on swimming activity of Ambystoma salamander larvae

    SciTech Connect

    Kutka, F.J. . Dept. of Animal Ecology)

    1994-11-01

    Swimming activity of larval Ambystoma laterale increased linearly with pH between pH 4.0 and 6.5; near inactivity occurred at pH 4.0. Ambystoma maculatum exhibited a weaker relationship between activity and pH, and overall was less active than A. laterale. However, survival of larval A. maculatum declined linearly with pH in the presence of adult diving beetles (Dytiscus verticalis), with significantly lower survival below pH 4.8. These results suggest that, as with embryos, salamander larvae may suffer from pH levels below 5.0, even though these levels are not directly lethal. Because of their sensitivity, ease, and short duration, activity tests are recommended with amphibian larvae for use in other risk assessments.

  2. Synaptic transmission from rods to rod-dominated bipolar cells in the tiger salamander retina.

    PubMed

    Yang, X L; Wu, S M

    1993-06-11

    Synaptic transmission between photoreceptors and bipolar cells was studied in dark-adapted tiger salamander retinas. Based on the relative light sensitivity, bipolar cells, either depolarizing (DBC) or hyperpolarizing (HBC), fell into two groups: one receives inputs primarily from rods (rod-dominated bipolar cells, DBCR and HBCR) and the other receives inputs primarily from cones (cone-dominated bipolar cells, DBCC and HBCC). The input-output relations of the rod-DBCR and rod-HBCR synapses were determined by plotting the voltage responses of the rod and DBCR (or HBCR) to dim 500-nm light steps, which polarizes only the rods but not the cones. The slope gains of both synapses were the highest near the dark rod voltage (-2.5 for the rod-DBCR synapse and 4.0 for the rod-HBCR synapse), and they (the absolute values) became progressively smaller at more hyperpolarized rod voltages. PMID:8186975

  3. Population Structure and Evolution after Speciation of the Hokkaido Salamander (Hynobius retardatus).

    PubMed

    Matsunami, Masatoshi; Igawa, Takeshi; Michimae, Hirofumi; Miura, Toru; Nishimura, Kinya

    2016-01-01

    The Hokkaido salamander (Hynobius retardatus) is endemic to Hokkaido Island, Japan, and shows intriguing flexible phenotypic plasticity and regional morphological diversity. However, to date, allozymes and partial mitochondria DNA sequences have provided only an outline of its demographic histories and the pattern of its genetic diversification. To understand the finer details of the population structure of this species and its evolution since speciation, we genotyped five regional populations by using 12 recently developed microsatellite polymorphic markers. We found a clear population structure with low gene flow among the five populations, but a close genetic relationship between the Teshio and Kitami populations. Our demographic analysis suggested that Teshio and Erimo had the largest effective population sizes among the five populations. These findings regarding the population structure and demography of H. retardatus improve our understanding of the faunal phylogeography on Hokkaido Island and also provide fundamental genetic information that will be useful for future studies. PMID:27257807

  4. Ultrastructure and histochemistry of the vas deferens of the salamander Rhyacotriton olympicus: adaptations for sperm storage.

    PubMed

    Zalisko, E J; Larsen, J H

    1988-06-01

    The vas deferens of the salamander Rhyacotriton olympicus is composed of (1) a peritoneal epithelium, (2) connective tissue with fibroblasts, melanophores, circular smooth muscle, capillaries, and unmyelinated nerves within a collagenous matrix, and (3) an inner layer of cuboidal epithelium partially covered by ciliated squamous cells at the lumen. The lumen and apical cytoplasm of both epithelial cell types contain strongly PAS-positive granules. The cuboidal cells contained numerous swollen rough endoplasmic reticulum cisternae, mitochondria, and apical dense granules suggesting a high degree of secretory activity possibly involved in sperm maintenance. Fewer mitochondria, rough endoplasmic reticula, and granules in squamous cells suggest less secretory activity. Squamous cells may protect the cuboidal cells from possible abrasion by sperm masses and/or their cilia may aid in distributing secretory products in the lumen. PMID:3399848

  5. Phylogeography of the salamander genus Pseudobranchus in the southeastern United States.

    PubMed

    Liu, Fu-Guo Robert; Moler, Paul E; Miyamoto, Michael M

    2006-04-01

    This study provides an extensive set of mitochondrial cytochrome b sequences for the salamander genus Pseudobranchus of the southeastern United States. These sequences were analysed by multiple phylogenetic methods that support a single set of major phylogeographic divisions for its two corroborated species (P. axanthus and P. striatus). These phylogeographic divisions overlap with the geographic breakpoints of other freshwater and terrestrial taxa in this region. Collectively, these overlapping patterns highlight the Central Highland and Tifton/Vidalia uplands as a significant barrier to Atlantic vs. Gulf coast groups, while reconfirming the phylogeographic significance of the Altamaha and Apalachicola river drainages. Despite their distinct phylogeographic split, P. striatus from west and east of these uplands are not currently recognizable as separate species according to the concordance principles for species definition. PMID:16289729

  6. Metabolism, gas exchange, and acid-base balance of giant salamanders.

    PubMed

    Ultsch, Gordon R

    2012-08-01

    The giant salamanders are aquatic and paedomorphic urodeles including the genera Andrias and Cryptobranchus (Cryptobranchidae), Amphiuma (Amphiumidae), Siren (Sirenidae), and Necturus (Proteidae, of which only N. maculosus is considered 'a giant'). Species in the genera Cryptobranchus and Necturus are considered aquatic salamanders well adapted for breathing water, poorly adapted for breathing air, and with limited abilities to compensate acid-base disturbances. As such, they are water-breathing animals with a somewhat fish-like respiratory and acid-base physiology, whose habitat selection is limited to waters that do not typically become hypoxic or hypercarbic (although this assertion has been questioned for N. maculosus). Siren and Amphiuma species, by contrast, are dependent upon air-breathing, have excellent lungs, inefficient (Siren) or no (Amphiuma) gills, and are obligate air-breathers with an acid-base status more similar to that of terrestrial tetrapods. As such, they can be considered to be air-breathing animals that live in water. Their response to the aquatic hypercarbia that they often encounter is to maintain intracellular pH (pH(i) ) and abandon extracellular pH regulation, a process that has been referred to as preferential pH(i) regulation. The acid-base status of some present-day tropical air-breathing fishes, and of Siren and Amphiuma, suggests that the acid-base transition from a low PCO(2) -low [] system typical of water-breathing fishes to the high PCO(2) -high [] systems of terrestrial tetrapods may have been completed before emergence onto land, and likely occurred in habitats that were typically both hypoxic and hypercarbic. PMID:22151821

  7. Retrotransposon long interspersed nucleotide element-1 (LINE-1) is activated during salamander limb regeneration

    PubMed Central

    Zhu, Wei; Kuo, Dwight; Nathanson, Jason; Satoh, Akira; Pao, Gerald M.; Yeo, Gene W.; Bryant, Susan V.; Voss, S. Randal; Gardiner, David M.; Hunter, Tony

    2012-01-01

    Salamanders possess an extraordinary capacity for tissue and organ regeneration when compared to mammals. In our effort to characterize the unique transcriptional fingerprint emerging during the early phase of salamander limb regeneration, we identified transcriptional activation of some germline-specific genes within the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells into a germline-like state. In this work, we focus on one of these genes, the long interspersed nucleotide element-1 (LINE-1) retrotransposon, which is usually active in germ cells and silent in most of the somatic tissues in other organisms. LINE-1 was found to be dramatically upregulated during regeneration. In addition, higher genomic LINE-1 content was also detected in the limb regenerate when compared to that before amputation indicating that LINE-1 retrotransposition is indeed active during regeneration. Active LINE-1 retrotransposition has been suggested to have a potentially deleterious impact on genomic integrity. Silencing of activated LINE-1 by small RNAs has been reported to be part of the machinery aiming to maintain genomic integrity. Indeed, we were able to identify putative LINE-1-related piRNAs in the limb blastema. Transposable element-related piRNAs have been identified frequently in the germline in other organisms. Thus, we present here a scenario in which a unique germline-like state is established during axolotl limb regeneration, and the re-activation of LINE-1 may serve as a marker for cellular dedifferentiation in the early-stage of limb regeneration. PMID:22913491

  8. Morphological variation in salamanders and their potential response to climate change

    PubMed Central

    Ficetola, Gentile Francesco; Colleoni, Emiliano; Renaud, Julien; Scali, Stefano; Padoa-Schioppa, Emilio; Thuiller, Wilfried

    2016-01-01

    Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here we built on the number of thoracic vertebrae (NTV) in ectothermic vertebrates, a known genetically-based feature, to establish a link with body size and evaluate how climate change might affect the future morphological response of this group of species. First we show that in old-world salamanders, NTV variation is strongly related to changes in body size. Secondly, using 22 salamander species as a case study, we found support for relationships between the spatial variation in selected bioclimatic variables and NTV for most of species. For 44% of species, precipitation and aridity were the predominant drivers of geographical variation of the NTV. Temperature features were dominant for 31% of species, while for 19% temperature and precipitation played a comparable role. This two-step analysis demonstrates that ectothermic vertebrates may evolve in response to climate change by modifying the number of thoracic vertebrae. These findings allow to develop scenarios for potential morphological evolution under future climate change, and to identify areas and species in which the most marked evolutionary responses are expected. Resistance to climate change estimated from species distribution models was positively related to present-day species morphological response, suggesting that the ability of morphological evolution may play a role for species’ persistence under climate change. The possibility that present-day capacity for local adaptation might help the resistance response to climate change can be integrated into analyses of the impact of global changes, and should also be considered when planning management actions

  9. Morphological variation in salamanders and their potential response to climate change.

    PubMed

    Ficetola, Gentile Francesco; Colleoni, Emiliano; Renaud, Julien; Scali, Stefano; Padoa-Schioppa, Emilio; Thuiller, Wilfried

    2016-06-01

    Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here, we built on the number of thoracic vertebrae (NTV) in ectothermic vertebrates, a known genetically based feature, to establish a link with body size and evaluate how climate change might affect the future morphological response of this group of species. First, we show that in old-world salamanders, NTV variation is strongly related to changes in body size. Secondly, using 22 salamander species as a case study, we found support for relationships between the spatial variation in selected bioclimatic variables and NTV for most of species. For 44% of species, precipitation and aridity were the predominant drivers of geographical variation of the NTV. Temperature features were dominant for 31% of species, while for 19% temperature and precipitation played a comparable role. This two-step analysis demonstrates that ectothermic vertebrates may evolve in response to climate change by modifying the number of thoracic vertebrae. These findings allow to develop scenarios for potential morphological evolution under future climate change and to identify areas and species in which the most marked evolutionary responses are expected. Resistance to climate change estimated from species distribution models was positively related to present-day species morphological response, suggesting that the ability of morphological evolution may play a role for species' persistence under climate change. The possibility that present-day capacity for local adaptation might help the resistance response to climate change can be integrated into analyses of the impact of global changes and should also be considered when planning management actions favouring

  10. Characterization and expression of cyp19a gene in the Chinese giant salamander Andrias davidianus.

    PubMed

    Hu, Qiaomu; Xiao, Hanbing; Tian, HaiFeng; Meng, Yan

    2016-02-01

    We cloned the full length cyp19a of Chinese giant salamander Andrias davidianus, determined its distribution in tissues and developing gonads, and analyzed the CpG methylation pattern of the cyp19a promoter. The results revealed isoforms of 1706 bp (G arom) and 1698 bp (B arom) in length, differing in the 5' flanking region, both encoding 502 amino acids. The G arom gene was observed mainly in the ovary and kidney, with little in other investigated tissues, while B arom expression was high in the brain, ovary, testis, and pituitary, with low or undetected expression in other examined tissues. Total aromatase expression was high in the ovary; moderate in the kidney, brain, testis, and pituitary; and low in the remaining tissues. G arom expression was significantly higher in the ovary than in the testis and gradually decreased with maturation of the salamander. A single injection of methyltestosterone or letrozole resulted in ovarian G arom expression decreasing over a 12-96 h period. A 1366 bp sequence of the cyp19a promoter was cloned and shown to be conserved in selected species. CpG methylation level was negatively correlated with cyp19a expression in the examined tissues and developing ovaries. Five and three CpG methylation sites positively correlated with DNA methylation levels in tissues and developing ovary, suggesting that they play an important role in regulating cyp19a expression. The aromatase gene showed two isoforms with distinct expression patterns, and the promoter methylation level at specific CpG sites was associated with variation in expression profiles of tissues and developing ovaries. PMID:26593771

  11. Correlates of asthma morbidity in primary care.

    PubMed Central

    Jones, K. P.; Bain, D. J.; Middleton, M.; Mullee, M. A.

    1992-01-01

    OBJECTIVES--To explore the morbidity of patients diagnosed as asthmatic in general practice, to examine the determinants of this morbidity, and to derive a simple morbidity screening tool for use in primary care. DESIGN--Patient interviews, lung function measurements, and data extraction from general practice case notes. SUBJECTS--300 asthmatic patients aged 5 to 65 years randomly selected from the repeat prescribing registers of three general practices in the Southampton area. MAIN OUTCOME MEASURES--Reported morbidity using a calculated index based on three questions (Are you in a wheezy or asthmatic condition at least once per week; Have you had time off work or school in the past year because of your asthma; Do you suffer from attacks of wheezing during the night?); mean forced expiratory volume in one second and mean peak expiratory flow (over a seven day period); diurnal variation in peak flow; and the relation of the morbidity index to lung function. RESULTS--Mean forced expiratory volume in one second was 67% predicted (SD 18.4), mean peak expiratory flow was 80% predicted (SD 18.9), and mean diurnal variation was 10% (SD 7.7). 76 subjects were classified as having low morbidity, 95 medium, and 125 high. The morbidity index was significantly associated with forced expiratory volume in one second, mean peak expiratory flow rate, and diurnal variation (p less than 0.05); it was not significantly associated with inhaler technique or use of prophylaxis. CONCLUSIONS--There was a large burden of persisting morbidity across all ages of patients diagnosed as asthmatic in the three well resourced practices studied. The use of the morbidity index may help to target the asthmatic patients needing more attention by concentrating on those reporting medium to high morbidity. PMID:1540736

  12. Diets and morbid tissues--history counts, present counts.

    PubMed

    Henkin, Yaakov; Kovsan, Julia; Gepner, Yftach; Shai, Iris

    2015-04-01

    Body fat distribution, especially visceral fat accumulation, may contribute more than total fat mass per se to the development of metabolic and cardiovascular disorders. Early prevention highly improves health outcomes later in life, especially when considering such cumulative conditions as atherosclerosis. However, as these processes emerge to be partly reversible, dietary and lifestyle interventions at any age and health condition are greatly beneficial. Given the worldwide abundance of metabolic and cardiovascular disorders, the identification and implementation of strategies for preventing or reducing the accumulation of morbid fat tissues is of great importance for preventing and regressing atherosclerosis. This review focuses on dietary strategies and specific food components that were demonstrated to alter body fat distribution and regression of atherosclerosis. Different properties of various adipose depots (superficial subcutaneous, deep subcutaneous and visceral fat depots) and their contribution to metabolic and cardiovascular disorders are briefly discussed. Visceral obesity and atherosclerosis should be approached as modifiable rather than ineluctable conditions. PMID:26148913

  13. Psychiatric morbidity associated with motor vehicle accidents.

    PubMed

    Blanchard, E B; Hickling, E J; Taylor, A E; Loos, W

    1995-08-01

    The primary purpose of this report was to determine the extent of psychiatric morbidity and comorbidity among a sample of recent victims of motor vehicle accidents (MVAs) in comparison to a nonaccident control population. Victims of recent MVAs (N = 158), who sought medical attention as a result of the MVA, were assessed in a University-based research clinic, 1 to 4 months after the accident for acute psychiatric and psychosocial consequences as well as for pre-MVA psychopathology using structured clinical interviews (Clinician-Administered PTSD Scale, SCID, SCID-II, LIFE Base). Age- and gender-matched controls (N = 93) who had had no MVAs in the past year served as controls. Sixty-two MVA victims (39.2%) met DSM-III-R criteria for posttraumatic stress disorder (PTSD), and 55 met DSM-IV criteria. The MVA victims who met the criteria for PTSD were more subjectively distressed and had more impairment in role function (performance at work/school/homemaking, relationships with family or friends) than the MVA victims who did not meet the PTSD criteria or the controls. A high percentage (53%) of the MVA-PTSD group also met the criteria for current major depression, with most of that developing after the MVA. A prior history of major depression appears to be a risk factor for developing PTSD after an MVA (p = .0004): 50% of MVA victims who developed PTSD had a history of previous major depression, as compared with 23% of those with a less severe reaction to the MVA. A prior history of PTSD from earlier trauma also is associated with developing PTSD or a subsyndromal form of it (25.2%) (p = .0012). Personal injury MVAs exact substantial psychosocial costs on the victims. Early intervention, especially in vulnerable populations, might prevent some of this. PMID:7643060

  14. Coprophagy in a cave-adapted salamander; the importance of bat guano examined through nutritional and stable isotope analyses

    PubMed Central

    Fenolio, Danté B; Graening, G.O; Collier, Bret A; Stout, Jim F

    2005-01-01

    During a two year population ecology study in a cave environment, 15 Eurycea (=Typhlotriton) spelaea were observed ingesting bat guano. Furthermore, E. spelaea capture numbers increased significantly during the time that grey bats (Myotis grisescens) deposited fresh guano. We investigated the hypothesis that this behaviour was not incidental to the capture of invertebrate prey, but a diet switch to an energy-rich detritus in an oligotrophic environment. Stable isotope assays determined that guano may be assimilated into salamander muscle tissue, and nutritional analyses revealed that guano is a comparable food source to potential invertebrate prey items. This is the first report of coprophagy in a salamander and in any amphibian for reasons other than intestinal inoculation. Because many temperate subterranean environments are often energy poor and this limitation is thought to select for increased diet breadth, we predict that coprophagy may be common in subterranean vertebrates where it is not currently recognized. PMID:16615210

  15. Comparison of direct, indirect, and ecosystem engineering effects of an earthworm on the red-backed salamander.

    PubMed

    Ransom, Tami S

    2012-10-01

    In addition to creating or modifying habitat, ecosystem engineers interact with other species as predators, prey, or competitors. The earthworm, Lumbricus terrestris, interacts with the common woodland salamander, Plethodon cinereus, via: (1) ecosystem engineering, by providing burrows that are used as a refuge, (2) direct effects as a prey item, and (3) indirectly, by competing with microinvertebrates, another prey item for P. cinereus. Using enclosures in the forest, I examined the relative strengths of these component pathways between seasons and salamander age classes. I found that the relative strength (partial eta2) of the positive direct (trophic) effect of L. terrestris on the change in mass of P. cineresus was greater than that of the negative indirect effect, but only in summer. Positive effects of ecosystem engineering were only evident over the winter as increased adult survival. This research has implications for how habitat provisioning complements more well-studied species interactions, such as competition and predation, within communities. PMID:23185881

  16. Co-morbid disorders in Tourette syndrome.

    PubMed

    Mol Debes, Nanette M M

    2013-01-01

    Tourette syndrome (TS) is often accompanied by other symptoms and syndromes. The two best-known co-morbidities are Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD), but also other conditions like rage-attacks, depression, and sleeping disturbances are frequent in persons with TS. Both in clinical cohorts and in population-based cohorts the prevalence of co-morbidities is high. The presence of co-morbid ADHD and/or OCD has an impact on psychosocial, educational, and neuropsychological consequences of TS and it is associated with higher rates of other co-morbid disorders, like rage, anxiety, and conduct disorders. The symptoms of a co-morbid disorder might appear prior to the time that tics reach clinical attention. The TS phenotype probably changes during the course of the disease. The exact aetiology of the co-occurrence of co-morbid disorders and TS is not known, but they probably all are neurotransmitter disorders. European guidelines recommend first-choice pharmacological treatment, but randomised double-blinded trials are needed. Professionals need to be aware of the close relationship between TS and co-morbidities in order to give the patients the right treatment and support. PMID:23187139

  17. Transcriptomic Analysis of Endangered Chinese Salamander: Identification of Immune, Sex and Reproduction-Related Genes and Genetic Markers

    PubMed Central

    Che, Rongbo; Sun, Yuena; Wang, Rixin; Xu, Tianjun

    2014-01-01

    Background The Chinese salamander (Hynobius chinensis), an endangered amphibian species of salamander endemic to China, has attracted much attention because of its value of studying paleontology evolutionary history and decreasing population size. Despite increasing interest in the Hynobius chinensis genome, genomic resources for the species are still very limited. A comprehensive transcriptome of Hynobius chinensis, which will provide a resource for genome annotation, candidate genes identification and molecular marker development should be generated to supplement it. Principal Findings We performed a de novo assembly of Hynobius chinensis transcriptome by Illumina sequencing. A total of 148,510 nonredundant unigenes with an average length of approximately 580 bp were obtained. In all, 60,388 (40.66%) unigenes showed homologous matches in at least one database and 33,537 (22.58%) unigenes were annotated by all four databases. In total, 41,553 unigenes were categorized into 62 sub-categories by BLAST2GO search, and 19,468 transcripts were assigned to 140 KEGG pathways. A large number of unigenes involved in immune system, local adaptation, reproduction and sex determination were identified, as well as 31,982 simple sequence repeats (SSRs) and 460,923 putative single nucleotide polymorphisms (SNPs). Conclusion This dataset represents the first transcriptome analysis of the Chinese salamander (Hynobius chinensis), an endangered species, to be also the first time of hynobiidae. The transcriptome will provide valuable resource for further research in discovery of new genes, protection of population, adaptive evolution and survey of various pathways, as well as development of molecule markers in Chinese salamander; and reference information for closely related species. PMID:24498226

  18. Using stable isotopes to test for trophic niche partitioning: a case study with stream salamanders and fish

    USGS Publications Warehouse

    Sepulveda, Adam; Lowe, Winsor H.; Marra, Peter P.

    2012-01-01

    5. Although we did not identify mechanisms that facilitate salamander and fish coexistence, our empirical data and use of novel approaches to describe the trophic niche did yield important insights on the role of predator–prey interactions and cannibalism as alternative coexistence mechanisms. In addition, we found that 95% kernel estimators are a simple and robust method to describe population-level measure of trophic structure.

  19. Interactive effects of temperature and glyphosate on the behavior of blue ridge two-lined salamanders (Eurycea wilderae).

    PubMed

    Gandhi, Jaina S; Cecala, Kristen K

    2016-09-01

    The objective of the present study was to evaluate the potential interactive effects of stream temperatures and environmentally relevant glyphosate-based herbicide concentrations on movement and antipredator behaviors of larval Eurycea wilderae (Blue Ridge two-lined salamander). Larval salamanders were exposed to 1 of 4 environmentally relevant glyphosate concentrations (0.00 µg acid equivalent [a.e.]/L, 0.73 µg a.e./L, 1.46 µg a.e./L, and 2.92 µg a.e./L) at either ambient (12 °C) or elevated (23 °C) water temperature. Behaviors observed included the exploration of a novel habitat, use of refuge, habitat selection relative to a potential predator, and burst movement distance. In the absence of glyphosate, temperature consistently affected movement and refuge-use behavior, with individuals moving longer distances more frequently and using refuge less at warm temperatures; however, when glyphosate was added, the authors observed inconsistent effects of temperature that may have resulted from differential toxicity at various temperatures. Larval salamanders made shorter, more frequent movements and demonstrated reduced burst distance at higher glyphosate concentrations. The authors also found that lower glyphosate concentrations sometimes had stronger effects than higher concentrations (i.e., nonmonotonic dose responses), suggesting that standard safety tests conducted only at higher glyphosate concentrations might overlook important sublethal effects on salamander behavior. These data demonstrate that sublethal effects of glyphosate-based herbicides on natural behaviors of amphibians can occur with short-term exposure to environmentally relevant concentrations. Environ Toxicol Chem 2016;35:2297-2303. © 2016 SETAC. PMID:26872413

  20. Evidence for multiple Pleistocene refugia in the postglacial expansion of the eastern tiger salamander, Ambystoma tigrinum tigrinum.

    PubMed

    Church, Sheri A; Kraus, Johanna M; Mitchell, Joseph C; Church, Don R; Taylor, Douglas R

    2003-02-01

    Pleistocene glaciations were important determinants of historical migration and, hence, current levels of genetic diversity within and among populations. In many cases, these historical migrations led to the existence of disjunct populations of plants and animals. However, the origin and timing of arrival of these disjunct populations is often debated. In the current study, we identify potential refugia and estimate the timing of vicariance events of the eastern tiger salamander, Ambystoma tigrinum tigrinum, using mitochondrial sequence data. The results suggest a vicariant event 0.75-2 million years ago, separating the tiger salamanders to the east and west of the Apalachicola River Basin. East of the Appalachians, there appear to be multiple independent refugia with little migration among the remaining populations. In particular, populations along the Atlantic Coastal Plain were likely isolated in a coastal plain refugium in the Carolinas. Migrants from this refugium were the likely source of colonists for populations occupying previously glaciated areas along the northeastern Atlantic Coast. A second potential refugium occurs in the Blue Ridge Mountains of western Virginia. This refugium contains a disjunct population of the eastern tiger salamander, as well as a community of nearly 70 other disjunct plant and animal species. The tiger salamanders here have been isolated from other populations for 200,000-500,000 years. These results suggest that disjunct mountain populations of Coastal Plain species may have existed in situ throughout the Pleistocene in Appalachian refugia. Therefore, these disjunct populations are not of recent origin, but rather exist as relicts of a warmer, more widespread fauna and flora that is now restricted to the Coastal Plain. PMID:12683533

  1. Osteological Variation among Extreme Morphological Forms in the Mexican Salamander Genus Chiropterotriton (Amphibia: Plethodontidae): Morphological Evolution And Homoplasy.

    PubMed

    Darda, David M; Wake, David B

    2015-01-01

    Osteological variation is recorded among and within four of the most distinctive species of the Mexican salamander genus Chiropterotriton. Analysis of the data is consistent with the monophyletic status of the genus and documents previously unrecorded intraspecific and interspecific variation. Most of the recorded variation involves qualitative and quantitative proportional differences, but four fixed differences constitute autapomorphic states that affirm and diagnose some species (C. dimidiatus, C. magnipes). Osteological variation in 15 characters is analyzed with respect to predictions generated from four hypotheses: 1) phylogeny, 2) adaptation to specific habitats (the four species include cave-dwelling, terrestrial, and arboreal forms), 3) size-free shape, and 4) size. High levels of intraspecific variation suggest that the characters studied are not subject to rigid functional constraints in salamanders, regardless of size. The pattern predicted by the hypothesis based on size differences seen among these four Chiropterotriton species matches most closely the observed pattern of relative skull robustness. Since size change and heterochrony are often associated in plethodontid evolution, it is likely that changes in developmental timing play a role in the morphological transitions among these morphologically diverse taxa. Webbed feet, miniaturization, body shape, and an unusual tarsal arrangement are morphologies exhibited in species of Chiropterotrition that are shown to be homoplastic with other clades of tropical plethodontids. Although extensive homoplasy in salamanders might be seen as a roadblock to unraveling phylogenetic hypotheses, the homologous developmental systems that appear to underlie such homoplasy may reveal common and consistent evolutionary processes at work. PMID:26060996

  2. Sustained ERK Activation Underlies Reprogramming in Regeneration-Competent Salamander Cells and Distinguishes Them from Their Mammalian Counterparts

    PubMed Central

    Yun, Maximina H.; Gates, Phillip B.; Brockes, Jeremy P.

    2014-01-01

    Summary In regeneration-competent vertebrates, such as salamanders, regeneration depends on the ability of various differentiated adult cell types to undergo natural reprogramming. This ability is rarely observed in regeneration-incompetent species such as mammals, providing an explanation for their poor regenerative potential. To date, little is known about the molecular mechanisms mediating natural reprogramming during regeneration. Here, we have identified the extent of extracellular signal-regulated kinase (ERK) activation as a key component of such mechanisms. We show that sustained ERK activation following serum induction is required for re-entry into the cell cycle of postmitotic salamander muscle cells, partially by promoting the downregulation of p53 activity. Moreover, ERK activation induces epigenetic modifications and downregulation of muscle-specific genes such as Sox6. Remarkably, while long-term ERK activation is found in salamander myotubes, only transient activation is seen in their mammalian counterparts, suggesting that the extent of ERK activation could underlie differences in regenerative competence between species. PMID:25068118

  3. Sensory feedback plays a significant role in generating walking gait and in gait transition in salamanders: a simulation study.

    PubMed

    Harischandra, Nalin; Knuesel, Jeremie; Kozlov, Alexander; Bicanski, Andrej; Cabelguen, Jean-Marie; Ijspeert, Auke; Ekeberg, Orjan

    2011-01-01

    Here, we investigate the role of sensory feedback in gait generation and transition by using a three-dimensional, neuro-musculo-mechanical model of a salamander with realistic physical parameters. Activation of limb and axial muscles were driven by neural output patterns obtained from a central pattern generator (CPG) which is composed of simulated spiking neurons with adaptation. The CPG consists of a body-CPG and four limb-CPGs that are interconnected via synapses both ipsilaterally and contralaterally. We use the model both with and without sensory modulation and four different combinations of ipsilateral and contralateral coupling between the limb-CPGs. We found that the proprioceptive sensory inputs are essential in obtaining a coordinated lateral sequence walking gait (walking). The sensory feedback includes the signals coming from the stretch receptor like intraspinal neurons located in the girdle regions and the limb stretch receptors residing in the hip and scapula regions of the salamander. On the other hand, walking trot gait (trotting) is more under central (CPG) influence compared to that of the peripheral or sensory feedback. We found that the gait transition from walking to trotting can be induced by increased activity of the descending drive coming from the mesencephalic locomotor region and is helped by the sensory inputs at the hip and scapula regions detecting the late stance phase. More neurophysiological experiments are required to identify the precise type of mechanoreceptors in the salamander and the neural mechanisms mediating the sensory modulation. PMID:22069388

  4. Osteological Variation among Extreme Morphological Forms in the Mexican Salamander Genus Chiropterotriton (Amphibia: Plethodontidae): Morphological Evolution And Homoplasy

    PubMed Central

    Darda, David M.; Wake, David B.

    2015-01-01

    Osteological variation is recorded among and within four of the most distinctive species of the Mexican salamander genus Chiropterotriton. Analysis of the data is consistent with the monophyletic status of the genus and documents previously unrecorded intraspecific and interspecific variation. Most of the recorded variation involves qualitative and quantitative proportional differences, but four fixed differences constitute autapomorphic states that affirm and diagnose some species (C. dimidiatus, C. magnipes). Osteological variation in 15 characters is analyzed with respect to predictions generated from four hypotheses: 1) phylogeny, 2) adaptation to specific habitats (the four species include cave-dwelling, terrestrial, and arboreal forms), 3) size-free shape, and 4) size. High levels of intraspecific variation suggest that the characters studied are not subject to rigid functional constraints in salamanders, regardless of size. The pattern predicted by the hypothesis based on size differences seen among these four Chiropterotriton species matches most closely the observed pattern of relative skull robustness. Since size change and heterochrony are often associated in plethodontid evolution, it is likely that changes in developmental timing play a role in the morphological transitions among these morphologically diverse taxa. Webbed feet, miniaturization, body shape, and an unusual tarsal arrangement are morphologies exhibited in species of Chiropterotrition that are shown to be homoplastic with other clades of tropical plethodontids. Although extensive homoplasy in salamanders might be seen as a roadblock to unraveling phylogenetic hypotheses, the homologous developmental systems that appear to underlie such homoplasy may reveal common and consistent evolutionary processes at work. PMID:26060996

  5. Stress echocardiography in patients with morbid obesity

    PubMed Central

    Senior, Roxy

    2016-01-01

    The incidence of significant obesity is rising across the globe. These patients often have a clustering of cardiovascular risk factors and are frequently referred for noninvasive cardiac imaging tests. Stress echocardiography (SE) is widely used for assessment of patients with known or suspected coronary artery disease (CAD), but its clinical utility in morbidly obese patients (in whom image quality may suffer due to body habitus) has been largely unknown. The recently published Stress Ultrasonography in Morbid Obesity (SUMO) study has shown that SE, when performed appropriately with ultrasound contrast agents (whether performed with physiological or pharmacological stress), has excellent feasibility and appropriately risk stratifies morbidly obese patients, including identification of patients who require revascularization. This article reviews the evidence supporting the use of echocardiographic techniques in morbidly obese patients for assessment of known or suspected CAD and briefly discusses other noninvasive modalities, including magnetic resonance and nuclear techniques, comparing and contrasting these techniques against SE. PMID:27249552

  6. Stress echocardiography in patients with morbid obesity.

    PubMed

    Shah, Benoy N; Senior, Roxy

    2016-06-01

    The incidence of significant obesity is rising across the globe. These patients often have a clustering of cardiovascular risk factors and are frequently referred for noninvasive cardiac imaging tests. Stress echocardiography (SE) is widely used for assessment of patients with known or suspected coronary artery disease (CAD), but its clinical utility in morbidly obese patients (in whom image quality may suffer due to body habitus) has been largely unknown. The recently published Stress Ultrasonography in Morbid Obesity (SUMO) study has shown that SE, when performed appropriately with ultrasound contrast agents (whether performed with physiological or pharmacological stress), has excellent feasibility and appropriately risk stratifies morbidly obese patients, including identification of patients who require revascularization. This article reviews the evidence supporting the use of echocardiographic techniques in morbidly obese patients for assessment of known or suspected CAD and briefly discusses other noninvasive modalities, including magnetic resonance and nuclear techniques, comparing and contrasting these techniques against SE. PMID:27249552

  7. Mortality and morbidity risks and economic behavior.

    PubMed

    Stoler, Avraham; Meltzer, David

    2013-02-01

    There are theoretical reasons to expect that high risk of mortality or morbidity during young adulthood decreases investment in human capital. However, investigation of this hypothesis is complicated by a variety of empirical challenges, including difficulties in inferring causation due to omitted variables and reverse causation. For example, to compare two groups with substantially different mortality rates, one typically has to use samples from different countries or periods, making it difficult to control for other relevant variables. Reverse causation is important because human capital investment can affect mortality and morbidity. To counter these problems, we collected data on human capital investments, fertility decisions, and other economic choices of people at risk for Huntington's disease. Huntington's disease is a fatal genetic disorder that introduces a large and exogenous risk of early mortality and morbidity. We find a strong negative relation between mortality and morbidity risks and human capital investment. PMID:22308067

  8. MORBIDITY AND MORTALITY WEEKLY REPORT (MMWR)

    EPA Science Inventory

    The Morbidity and Mortality Weekly Report (MMWR) is used to disseminate weekly provisional data on nationally notifiable infectious diseases. These provisional data are used for program planning and evaluation, monitoring trends in incidence, and detecting disease outbreaks.

  9. Overpaying morbidity adjusters in risk equalization models.

    PubMed

    van Kleef, R C; van Vliet, R C J A; van de Ven, W P M M

    2016-09-01

    Most competitive social health insurance markets include risk equalization to compensate insurers for predictable variation in healthcare expenses. Empirical literature shows that even the most sophisticated risk equalization models-with advanced morbidity adjusters-substantially undercompensate insurers for selected groups of high-risk individuals. In the presence of premium regulation, these undercompensations confront consumers and insurers with incentives for risk selection. An important reason for the undercompensations is that not all information with predictive value regarding healthcare expenses is appropriate for use as a morbidity adjuster. To reduce incentives for selection regarding specific groups we propose overpaying morbidity adjusters that are already included in the risk equalization model. This paper illustrates the idea of overpaying by merging data on morbidity adjusters and healthcare expenses with health survey information, and derives three preconditions for meaningful application. Given these preconditions, we think overpaying may be particularly useful for pharmacy-based cost groups. PMID:26420555

  10. Systemic lupus erythematosus presenting as morbid jealousy.

    PubMed Central

    Ravindran, A.; Carney, M. W.; Denman, A. M.

    1980-01-01

    A patient fulfilling the diagnostic criteria for systemic lupus erythematosus and presenting with morbid jealousy is described. There was evidence of cerebral lupus. Her physical and mental symptoms responded to a combination of chlorpromazine and steroids. The morbid mental process was probably caused by her physical condition while the content of her disordered thought and behaviour was determined by her introverted premorbid personality, religiosity, unhappy childhood experiences and frustrated desire for children. PMID:7413541

  11. Prospective morbidity surveillance of Shell refinery and petrochemical employees.

    PubMed

    Tsai, S P; Dowd, C M; Cowles, S R; Ross, C E

    1991-03-01

    Results for a prospective morbidity study of 14,170 refinery and chemical workers from 1981 through 1988 are presented. Illness/absence data for this study were extracted from the morbidity section of the Shell Health Surveillance System which includes records of all illness/absences in excess of five days. Age adjusted annual morbidity frequency rates and annual durations of absence are presented by age, sex, job, and work status. Generally, rates and durations of absence were highest for older age groups, women, and production workers. Increased risk was associated with the presence of known disease risk factors. Overall, 48% of the employees had at least one illness/absence in excess of five days during the eight year period. Twelve per cent of the employees had four or more absences, which accounted for 54% of the total number of absences and 52% of the total work days lost. Among men, the five most common conditions accounted for 72% of all illness/absences. In descending order they were injuries (25%), respiratory illnesses (17%), musculoskeletal disorders (14%), digestive illnesses (9%), and heart disease (7%). Similar patterns were noted among women. These findings may be useful in setting priorities and directing efforts such as health education programmes and other strategies for the prevention of disease. PMID:2015205

  12. Deep divergences and extensive phylogeographic structure in a clade of lowland tropical salamanders

    PubMed Central

    2012-01-01

    Background The complex geological history of Mesoamerica provides the opportunity to study the impact of multiple biogeographic barriers on population differentiation. We examine phylogeographic patterns in a clade of lowland salamanders (Bolitoglossa subgenus Nanotriton) using two mitochondrial genes and one nuclear gene. We use several phylogeographic analyses to infer the history of this clade and test hypotheses regarding the geographic origin of species and location of genetic breaks within species. We compare our results to those for other taxa to determine if historical events impacted different species in a similar manner. Results Deep genetic divergence between species indicates that they are relatively old, and two of the three widespread species show strong phylogeographic structure. Comparison of mtDNA and nuclear gene trees shows no evidence of hybridization or introgression between species. Isolated populations of Bolitoglossa rufescens from Los Tuxtlas region constitute a separate lineage based on molecular data and morphology, and divergence between Los Tuxtlas and other areas appears to predate the arrival of B. rufescens in other areas west of the Isthmus of Tehuantepec. The Isthmus appears responsible for Pliocene vicariance within B. rufescens, as has been shown for other taxa. The Motagua-Polochic fault system does not appear to have caused population vicariance, unlike in other systems. Conclusions Species of Nanotriton have responded to some major geological events in the same manner as other taxa, particularly in the case of the Isthmus of Tehuantepec. The deep divergence of the Los Tuxtlas populations of B. rufescens from other populations highlights the contribution of this volcanic system to patterns of regional endemism, and morphological differences observed in the Los Tuxtlas populations suggests that they may represent an undescribed species of Bolitoglossa. The absence of phylogeographic structure in B. nympha, in contrast to the

  13. Life history differences influence the impacts of drought on two pond-breeding salamanders.

    PubMed

    Anderson, Thomas L; Ousterhout, Brittany H; Peterman, William E; Drake, Dana L; Semlitsch, Raymond D

    2015-10-01

    Drought is a strong density-independent environmental filter that contributes to population regulation and other ecological processes. Not all species respond similarly to drought, and the overall impacts can vary depending on life histories. Such differences can necessitate management strategies that incorporate information on individual species to maximize conservation success. We report the effects of a short-term drought on occupancy and reproductive success of two pond-breeding salamanders that differ in breeding phenology (fall vs. spring breeder) across an active military base landscape in Missouri, USA: We surveyed ~200 ponds for the presence of eggs, larvae, and metamorphs from 2011 to 2013. This period coincided with before, during, and after a severe drought that occurred in 2012. The two species showed contrasting responses to drought, where high reproductive failure (34% of ponds) was observed for the spring breeder during a single drought year. Alternatively, the fall breeder only showed a cumulative 8% failure over two years. The number of breeding ponds available for use in the fall decreased during the drought due to pond drying and/or a lack of re-filling. Estimates of occupancy probability declined for the fall-breeding salamander between 2012 and 2013, whereas occupancy probability estimates of the spring breeder increased post-drought. The presence of fish, hydroperiod, the amount of forest cover surrounding ponds, and canopy cover were all found to affect estimates of occupancy probabilities of each species. Pond clustering (distance to nearest pond and the number of ponds within close proximity), hydroperiod, forest cover, and canopy cover influenced both estimates of colonization and extinction probabilities. Our results show life history variation can be important in determining the relative susceptibility of a species to drought conditions, and that sympatric species experiencing the same environmental conditions can respond differently

  14. Biogeography, phylogeny, and morphological evolution of central Texas cave and spring salamanders

    PubMed Central

    2013-01-01

    Background Subterranean faunal radiations can result in complex patterns of morphological divergence involving both convergent or parallel phenotypic evolution and cryptic species diversity. Salamanders of the genus Eurycea in central Texas provide a particularly challenging example with respect to phylogeny reconstruction, biogeography and taxonomy. These predominantly aquatic species inhabit karst limestone aquifers and spring outflows, and exhibit a wide range of morphological and genetic variation. We extensively sampled spring and cave populations of six Eurycea species within this group (eastern Blepsimolge clade), to reconstruct their phylogenetic and biogeographic history using mtDNA and examine patterns and origins of cave- and surface-associated morphological variation. Results Genetic divergence is generally low, and many populations share ancestral haplotypes and/or show evidence of introgression. This pattern likely indicates a recent radiation coupled with a complex history of intermittent connections within the aquatic karst system. Cave populations that exhibit the most extreme troglobitic morphologies show no or very low divergence from surface populations and are geographically interspersed among them, suggesting multiple instances of rapid, parallel phenotypic evolution. Morphological variation is diffuse among cave populations; this is in contrast to surface populations, which form a tight cluster in morphospace. Unexpectedly, our analyses reveal two distinct and previously unrecognized morphological groups encompassing multiple species that are not correlated with spring or cave habitat, phylogeny or geography, and may be due to developmental plasticity. Conclusions The evolutionary history of this group of spring- and cave-dwelling salamanders reflects patterns of intermittent isolation and gene flow influenced by complex hydrogeologic dynamics that are characteristic of karst regions. Shallow genetic divergences among several species

  15. Sodium-dependent calcium extrusion and sensitivity regulation in retinal cones of the salamander.

    PubMed Central

    Nakatani, K; Yau, K W

    1989-01-01

    1. Membrane current was recorded from an isolated, dark-adapted salamander cone by sucking its inner segment into a tight-fitting glass pipette containing Ringer solution. The outer segment of the cell was exposed to a bath solution that could be changed rapidly. 2. After removing Na+ from the bath Ringer solution for a short period of time in darkness (the 'loading period'), a transient inward current was observed upon restoring it in bright light. A similar but longer-lasting current was observed when Na+ was restored in the light after a large Ca2+ influx was induced through the light-sensitive conductance in darkness. 3. The above transient current was not observed if Li+ or guanidinium was substituted for Na+ in the light, or if Ba2+ was substituted for Ca2+ during the dark loading period. However, a current was observed if Sr2+ was the substituting ion for Ca2+ during loading. These observations suggested that the current was associated with an electrogenic Na+-dependent Ca2+ efflux at the cone outer segment. 4. The saturated amplitude of the exchange current was 12-25 pA with a mean around 16 pA. This is very comparable to that measured in the outer segment of a salamander rod under similar conditions. 5. By comparing a known Ca2+ load in a cone outer segment to the subsequent charge transfer through the exchange, we estimated that the stoichiometry of the exchange was near 3Na+:1Ca2+. 6. With a small Ca2+ load, or in the presence of Cs+ around the inner segment, the final temporal decline of the Na+-Ca2+ exchange current was roughly exponential, with a mean time constant of about 100 ms. This decline is about four times faster than that measured in rods. We interpret the shorter time constant in cones to reflect a faster rate of decline of intracellular free Ca2+ in their outer segments resulting from the exchange activity. 7. In the absence of external Na+, and hence any Na+-dependent Ca2+ efflux, the absolute sensitivity of a cone to a dim flash was

  16. Clinician challenges in providing health care for a morbidly obese family member: a bariatric case study.

    PubMed

    Beitz, Janice M

    2015-01-01

    Morbid obesity is a chronic disease affecting millions of Americans. The disorder is likely to increase in prevalence because currently one third of the American population is obese. Many factors are associated with morbid obesity, including psychological (eg, depression), physiological (eg, hypothyroidism) mechanisms, sleep disorders (eg, sleep apnea), drug therapy (antidepressants, antidiabetic agents, steroids), and genetics. Increasing numbers of morbidly obese patients are requiring critical care, presenting major challenges to professional staff across the disciplines. This manuscript presents a case study describing the experiences of a morbidly obese woman in the final years of her life from the perspective of her health professional relative. The patient typifies many of the major risk factors for morbid obesity; her story reveals many of the issues faced as she revolved in and out of the critical care and acute care system. Her substantive health problems affected multiple body systems and included hypothyroidism, congestive heart failure, hyperlipidemia, and subclinical Cushing's Syndrome, likely related to previous medical therapy (cortisone) for rheumatic fever in childhood. The case description addresses many integumentary system issues the patient experienced; skin injuries and infections that can pose serious life-threatening situations for the morbidly obese patient must be prevented or treated efficiently. Health professionals can learn a great deal and improve the care they provide by listening to morbidly obese patients. PMID:25581606

  17. Alcoholism and co-morbid psychiatric disorders among American Indians.

    PubMed

    Westermeyer, J

    2001-01-01

    Much of the data reported here regarding American Indian (AI) people has originated from specific areas with particular peoples. Thus, one must be cautious in applying information from one tribe to the hundreds of tribes living across the United States. As with any people, psychiatric disorder may be a pre-existing rationale for using alcohol. Or alternatively, alcohol may lead to various psychiatric disorders, such as organic mental conditions, posttraumatic stress disorder, or other conditions. A third alternative is that both alcoholism and other psychiatric disorder merely happen to affect the same person by chance. Recognizing alcoholism and treating it in a timely manner before disabling or even permanent psychiatric disorders ensue are key strategies. In addition, clinicians must be able to recognize and then either treat or refer co-morbid patients for appropriate care. Some psychiatric disorders, such as panic disorder, posttraumatic stress disorder, and various organic mental disorders may occur more often in some AI groups. Other co-morbid conditions, such as eating disorders, may occur less often among AI patients with alcoholism. It could be argued that resources should go solely to preventive efforts, thereby negating the need for psychiatric services. However, successful prevention of alcoholism may hinge upon, and increase the need for greater psychiatric services in AI communities. PMID:11698982

  18. Genetic drift and rapid evolution of viviparity in insular fire salamanders (Salamandra salamandra).

    PubMed

    Velo-Antón, G; Zamudio, K R; Cordero-Rivera, A

    2012-04-01

    Continental islands offer an excellent opportunity to investigate adaptive processes and to time microevolutionary changes that precede macroevolutionary events. We performed a population genetic study of the fire salamander (Salamandra salamandra), a species that displays unique intraspecific diversity of reproductive strategies, to address the microevolutionary processes leading to phenotypic and genetic differentiation of island, coastal and interior populations. We used eight microsatellite markers to estimate genetic diversity, population structure and demographic parameters in viviparous insular populations and ovoviviparous coastal and interior populations. Our results show considerable genetic differentiation (F(ST) range: 0.06-0.27), and no clear signs of gene flow among populations, except between the large and admixed interior populations. We find no support for island colonization by rafting or intentional/accidental anthropogenic introductions, indicating that rising sea levels were responsible for isolation of the island populations approximately 9000 years ago. Our study provides evidence of rapid genetic differentiation between island and coastal populations, and rapid evolution of viviparity driven by climatic selective pressures on island populations, geographic isolation with genetic drift, or a combination of these factors. Studies of these viviparous island populations in early stages of divergence help us better understand the microevolutionary processes involved in rapid phenotypic shifts. PMID:22086081

  19. Cryptic sex? Estimates of genome exchange in unisexual mole salamanders (Ambystoma sp.).

    PubMed

    Gibbs, H Lisle; Denton, Robert D

    2016-06-01

    Cryptic sex has been argued to explain the exceptional longevity of certain parthenogenetic vertebrate lineages, yet direct measurements of genetic exchange between sexual and apparently parthenogenetic forms are rare. Female unisexual mole salamanders (Ambystoma sp.) are the oldest known unisexual vertebrate lineage (~5 million years), and one hypothesis for their persistence is that allopolyploid female unisexuals periodically exchange haploid genomes 'genome exchange' during gynogenetic reproduction with males from sympatric sexual species. We test this hypothesis by using genome-specific microsatellite DNA markers to estimate the rates of genome exchange between sexual males and unisexual females in two ponds in NE Ohio. We also test the prediction that levels of gene flow should be higher for 'sympatric' (sexual males present) genomes in unisexuals compared to 'allopatric' (sexual males absent) unisexual genomes. We used a model testing framework in the coalescent-based program MIGRATE-N to compare models where unidirectional gene flow is present and absent between sexual species and unisexuals. As predicted, our results show higher levels of gene flow between sexuals and sympatric unisexual genomes compared to lower (likely artefactual) levels of gene flow between sexuals and allopatric unisexual genomes. Our results provide direct evidence that genome exchange between sexual and unisexual Ambystoma occurs and demonstrate that the magnitude depends on which sexual species are present. The relatively high levels of gene flow suggest that unisexuals must be at a selective advantage over sexual forms so as to avoid extinction due to genetic swamping through genome exchange. PMID:27100619

  20. Temporally adaptive sampling: a case study in rare species survey design with marbled salamanders (Ambystoma opacum).

    PubMed

    Charney, Noah D; Kubel, Jacob E; Eiseman, Charles S

    2015-01-01

    Improving detection rates for elusive species with clumped distributions is often accomplished through adaptive sampling designs. This approach can be extended to include species with temporally variable detection probabilities. By concentrating survey effort in years when the focal species are most abundant or visible, overall detection rates can be improved. This requires either long-term monitoring at a few locations where the species are known to occur or models capable of predicting population trends using climatic and demographic data. For marbled salamanders (Ambystoma opacum) in Massachusetts, we demonstrate that annual variation in detection probability of larvae is regionally correlated. In our data, the difference in survey success between years was far more important than the difference among the three survey methods we employed: diurnal surveys, nocturnal surveys, and dipnet surveys. Based on these data, we simulate future surveys to locate unknown populations under a temporally adaptive sampling framework. In the simulations, when pond dynamics are correlated over the focal region, the temporally adaptive design improved mean survey success by as much as 26% over a non-adaptive sampling design. Employing a temporally adaptive strategy costs very little, is simple, and has the potential to substantially improve the efficient use of scarce conservation funds. PMID:25799224

  1. Linking extinction–colonization dynamics to genetic structure in a salamander metapopulation

    PubMed Central

    Cosentino, Bradley J.; Phillips, Christopher A.; Schooley, Robert L.; Lowe, Winsor H.; Douglas, Marlis R.

    2012-01-01

    Theory predicts that founder effects have a primary role in determining metapopulation genetic structure. However, ecological factors that affect extinction–colonization dynamics may also create spatial variation in the strength of genetic drift and migration. We tested the hypothesis that ecological factors underlying extinction–colonization dynamics influenced the genetic structure of a tiger salamander (Ambystoma tigrinum) metapopulation. We used empirical data on metapopulation dynamics to make a priori predictions about the effects of population age and ecological factors on genetic diversity and divergence among 41 populations. Metapopulation dynamics of A. tigrinum depended on wetland area, connectivity and presence of predatory fish. We found that newly colonized populations were more genetically differentiated than established populations, suggesting that founder effects influenced genetic structure. However, ecological drivers of metapopulation dynamics were more important than age in predicting genetic structure. Consistent with demographic predictions from metapopulation theory, genetic diversity and divergence depended on wetland area and connectivity. Divergence was greatest in small, isolated wetlands where genetic diversity was low. Our results show that ecological factors underlying metapopulation dynamics can be key determinants of spatial genetic structure, and that habitat area and isolation may mediate the contributions of drift and migration to divergence and evolution in local populations. PMID:22113029

  2. [Episodes of adaptive evolution of mitochondrial genome in Asiatic salamanders (Amphibia, Caudata, Hynobiidae)].

    PubMed

    Maliarchuk, B A; Derenko, M V; Denisova, G A

    2014-02-01

    To elucidate the effect of natural selection on the evolution of mitochondrial DNA (mtDNA) in Asiatic salamanders of the family Hynobiidae, nucleotide sequences of 12 protein-coding genes were analyzed. Using a mixed effects model of evolution, it was found that, in spite of the pronounced effect of negative selection on the mtDNA evolution in Hynobiidae (which is typical for the animals in general), two phylogenetic clusters, the West Asian one, represented by the genera Ranodon and Paradactylodon, and North Eurasian one, represented by the genus Salamandrella, were formed under the influence of episodic positive selection. Analysis of protein sequences encoded by the mitochondrial genome also supported the influence of positive selection on the evolution of Hynobiidae at some stages of their cladogenesis. It is suggested that the signatures of adaptive evolution detected in the mtDNA of Hynobiidae were determined by the complex and long-lasting history of their formation, accompanied by adaptation to the changing environment. PMID:25711027

  3. Morphological homoplasy, life history evolution, and historical biogeography of plethodontid salamanders inferred from complete mitochondrial genomes

    SciTech Connect

    Mueller, Rachel Lockridge; Macey, J. Robert; Jaekel, Martin; Wake, David B.; Boore, Jeffrey L.

    2004-08-01

    The evolutionary history of the largest salamander family (Plethodontidae) is characterized by extreme morphological homoplasy. Analysis of the mechanisms generating such homoplasy requires an independent, molecular phylogeny. To this end, we sequenced 24 complete mitochondrial genomes (22 plethodontids and two outgroup taxa), added data for three species from GenBank, and performed partitioned and unpartitioned Bayesian, ML, and MP phylogenetic analyses. We explored four dataset partitioning strategies to account for evolutionary process heterogeneity among genes and codon positions, all of which yielded increased model likelihoods and decreased numbers of supported nodes in the topologies (PP > 0.95) relative to the unpartitioned analysis. Our phylogenetic analyses yielded congruent trees that contrast with the traditional morphology-based taxonomy; the monophyly of three out of four major groups is rejected. Reanalysis of current hypotheses in light of these new evolutionary relationships suggests that (1) a larval life history stage re-evolved from a direct-developing ancestor multiple times, (2) there is no phylogenetic support for the ''Out of Appalachia'' hypothesis of plethodontid origins, and (3) novel scenarios must be reconstructed for the convergent evolution of projectile tongues, reduction in toe number, and specialization for defensive tail loss. Some of these novel scenarios imply morphological transformation series that proceed in the opposite direction than was previously thought. In addition, they suggest surprising evolutionary lability in traits previously interpreted to be conservative.

  4. Neural induction in the absence of Organizer in salamanders is mediated by Ras/MAPK

    PubMed Central

    Hurtado, Cecilia; De Robertis, E. M.

    2007-01-01

    Research on the mechanisms of embryonic induction had a great setback in the 1940s when Barth discovered and Holtfreter confirmed that ectoderm of Ambystoma maculatum salamander embryos could form brain tissue when cultured in a simple saline solution. We have revisited this classical experiment and found that when cultured animal cap ectoderm attaches to a glass substratum, it can self-organize to form complex organs such as brain vesicles, eyes, lens and olfactory placodes. Only anterior neural organs were generated. Under these culture conditions ERK became diphosphorylated, indicating a sustained activation of the Ras/MAPK pathway. Using sand particles as an heterologous neural inducer similar results were obtained. Addition of U0126, a specific antagonist of MEK, the enzyme that phosphorylates ERK/MAPK, inhibited neural differentiation. The closely related control compound U0124 had no effect. We conclude that neural induction in the absence of organizer in Ambystoma maculatum requires Ras/MAPK activation. These findings provide a molecular explanation for the activity of heterologous neural inducers that dominated thinking in amphibian experimental embryology for many decades. PMID:17540356

  5. Effects of copper exposure on hatching success and early larval survival in marbled salamanders, Ambystoma opacum.

    PubMed

    Soteropoulos, Diana L; Lance, Stacey L; Flynn, R Wesley; Scott, David E

    2014-07-01

    The creation of wetlands, such as urban and industrial ponds, has increased in recent decades, and these wetlands often become enriched in pollutants over time. One metal contaminant trapped in created wetlands is copper (Cu(2+)). Copper concentrations in sediments and overlying water may affect amphibian species that breed in created wetlands. The authors analyzed the Cu concentration in dried sediments from a contaminated wetland and the levels of aqueous Cu released after flooding the sediments with different volumes of water, mimicking low, medium, and high pond-filling events. Eggs and larvae of Ambystoma opacum Gravenhorst, a salamander that lays eggs on the sediments in dry pond beds that hatch on pond-filling, were exposed to a range of Cu concentrations that bracketed potential aqueous Cu levels in created wetlands. Embryo survival varied among clutches, but increased Cu levels did not affect embryo survival. At Cu concentrations of 500 µg/L or greater, however, embryos hatched earlier, and the aquatic larvae died shortly after hatching. Because Cu concentrations in sediments increase over time in created wetlands, even relatively tolerant species such as A. opacum may be affected by Cu levels in the posthatching environment. PMID:24729474

  6. Geographic variation, genetic structure and conservation unit designation in the larch mountain salamander( Plethodon larselli)

    USGS Publications Warehouse

    Wagner, R.S.; Miller, Mark P.; Crisafulli, Charles; Haig, Susan M.

    2005-01-01

    The Larch Mountain salamander (Plethodon larselli Burns, 1954) is an endemic species in the Pacific northwestern United States facing threats related to habitat destruction. To facilitate development of conservation strategies, we used DNA sequences and RAPDs (random amplified polymorphic DNA) to examine differences among populations of this species. Phylogenetic analyses of cytochrome b revealed a clade of haplotypes from populations north of the Columbia River derived from a clade containing haplotypes from the river's southwestern region. Haplotypes from southeastern populations formed a separate clade. Nucleotide diversity was reduced in northern populations relative to southern populations. These results were corroborated by analyses of RAPD loci, which revealed similar patterns of clustering and diversity. Network analyses suggested that northern populations were colonized following a range expansion mediated by individuals from populations located southwest of the river. Changes in the Columbia River's location during the Pliocene and Pleistocene likely released distributional constraints on this species, permitting their northern range expansion. Based on the barrier presented by the Columbia River's present location and differences in haplotype diversity and population structure observed between northern and southern populations, we suggest that designation of separate management units encompassing each region may assist with mitigating different threats to this species.

  7. Generalisation within specialization: inter-individual diet variation in the only specialized salamander in the world

    PubMed Central

    Costa, Andrea; Salvidio, Sebastiano; Posillico, Mario; Matteucci, Giorgio; De Cinti, Bruno; Romano, Antonio

    2015-01-01

    Specialization is typically inferred at population and species level but in the last decade many authors highlighted this trait at the individual level, finding that generalist populations can be composed by both generalist and specialist individual. Despite hundreds of reported cases of individual specialization there is a complete lack of information on inter-individual diet variation in specialist species. We studied the diet of the Italian endemic Spectacled Salamander (Salamandrina perspicillata), in a temperate forest ecosystem, to disclose the realised trophic niche, prey selection strategy in function of phenotypic variation and inter-individual diet variation. Our results showed that Salamandrina is highly specialized on Collembola and the more specialized individuals are the better performing ones. Analyses of inter-individual diet variation showed that a subset of animals exhibited a broader trophic niche, adopting different foraging strategies. Our findings reflects the optimal foraging theory both at population and individual level, since animals in better physiological conditions are able to exploit the most profitable prey, suggesting that the two coexisting strategies are not equivalent. At last this species, feeding on decomposers of litter detritus, could play a key role determining litter retention rate, nutrient cycle and carbon sequestration. PMID:26292804

  8. Variation in cannibalistic polyphenism between populations in the salamander Hynobius retardatus.

    PubMed

    Michimae, Hirofumi; Wakahara, Masami

    2002-06-01

    Organisms sometimes change their phenotype to maximize fitness according to local environments. If the frequency of the broad-headed "cannibal" morph in the larvae of the salamander Hynobius retardatus has been evolutionarily maintained at a certain level within a population as a result of local adaptation, variations in its frequency should be found among different populations with environmental variation. We investigated whether variations in the frequency of the broad-headed morph were present in 2 different populations, Nopporo (a low-density population) and Erimo (a high-density population), by raising larvae from the respective populations under the same experimental conditions. The occurrence rate of the broad-headed "cannibal" morph was significantly different between the 2 populations when examined with different experimental larval densities. These results suggest that the reaction norm with respect to the frequency of the broad-headed morph is different between the Nopporo and Erimo populations. Because the local populations are assumed to be selected for under different environments, the different reaction norm might have evolved in response to different selection pressures. PMID:12130800

  9. Temporally Adaptive Sampling: A Case Study in Rare Species Survey Design with Marbled Salamanders (Ambystoma opacum)

    PubMed Central

    Charney, Noah D.; Kubel, Jacob E.; Eiseman, Charles S.

    2015-01-01

    Improving detection rates for elusive species with clumped distributions is often accomplished through adaptive sampling designs. This approach can be extended to include species with temporally variable detection probabilities. By concentrating survey effort in years when the focal species are most abundant or visible, overall detection rates can be improved. This requires either long-term monitoring at a few locations where the species are known to occur or models capable of predicting population trends using climatic and demographic data. For marbled salamanders (Ambystoma opacum) in Massachusetts, we demonstrate that annual variation in detection probability of larvae is regionally correlated. In our data, the difference in survey success between years was far more important than the difference among the three survey methods we employed: diurnal surveys, nocturnal surveys, and dipnet surveys. Based on these data, we simulate future surveys to locate unknown populations under a temporally adaptive sampling framework. In the simulations, when pond dynamics are correlated over the focal region, the temporally adaptive design improved mean survey success by as much as 26% over a non-adaptive sampling design. Employing a temporally adaptive strategy costs very little, is simple, and has the potential to substantially improve the efficient use of scarce conservation funds. PMID:25799224

  10. No Sexual Dimorphism Detected in Digit Ratios of the Fire Salamander (Salamandra salamandra).

    PubMed

    Balogová, Monika; Nelson, Emma; Uhrin, Marcel; Figurová, Mária; Ledecký, Valent; Zyśk, Bartłomiej

    2015-10-01

    It has been proposed that digit ratio may be used as a biomarker of early developmental effects. Specifically, the second-to-fourth digit ratio (2D:4D) has been linked to the effects of sex hormones and their receptor genes, but other digit ratios have also been investigated. Across taxa, patterns of sexual dimorphism in digit ratios are ambiguous and a scarcity of studies in basal tetrapods makes it difficult to understand how ratios have evolved. Here, we focus on examining sex differences in digit ratios (2D:3D, 2D:4D, and 3D:4D) in a common amphibian, the fire salamander (Salamandra salamandra). We used graphic software to measure soft tissue digit length and digit bone length from X-rays. We found a nonsignificant tendency in males to have a lower 2D:3D than females; however, no sexual differences were detected in the other ratios. We discuss our results in the context of other studies of digit ratios, and how sex determination systems, as well as other factors, might impact patterns of sexual dimorphism, particularly in reptiles and in amphibians. Our findings suggest that caution is needed when using digit ratios as a potential indicator of prenatal hormonal effects in amphibians and highlight the need for more comparative studies to elucidate the evolutionary and genetic mechanisms implicated in sexually dimorphic patterns across taxonomic groups. PMID:26199217

  11. Acute toxicity of some hydrazine compounds to salamander larvae, Ambystoma spp

    SciTech Connect

    Slonim, A.R.

    1986-11-01

    Although hydrazine compounds have been used extensively by industry for a very long time, they have become important in recent years as propellants for aerospace operations. The study of hydrazine compounds in this laboratory began about two decades ago and developed into a large pharmacological and toxicological research program that included also environmental considerations. Subsequently, acute toxicity studies were conducted on the common guppy (Lebistes reticulatus Peters) using four hydrazine compounds of interest. The toxicity of these propellants were evaluated next on other species of aquatic organisms such as mosquito fish (Gambusia affinis) and amphibians. Two different studies were conducted on amphibians: One utilized amphibian eggs and the other amphibian larvae. The larvae of spotted and marbled salamanders (Ambystoma maculatum and A. opacum, respectively) were used primarily in numerous static bioassays to determine the acute toxicity of hydrazine, UDMH and Aerozine-50 on these organisms. The remaining larvae were used in other tests mainly to corroborate previous experimental results (e.g., to see whether toxicity is affected by organism size, aeration of test solutions, and water hardness). The results on the larvae are presented in this paper.

  12. Localization of glycine, GABA and neuropeptide containing neurons in tiger salamander retina

    SciTech Connect

    Yang, C.Y.

    1988-01-01

    Putative glycinergic and GABAergic neurons in the salamander retina were localized by a parallel analysis of high affinity {sup 3}H-glycine uptake and glycine-like immunoreactivity (Gly-IR) and a comparative analysis of high affinity {sup 3}H-GABA uptake, GABA, like immunoreactivity (GABA-IR), and glutamate decarboxylase immunoreactivity (GAD-IR) at the light microscopic level. Good correspondence of labeling of {sup 3}H-glycine uptake and Gly-IR as well as that of {sup 3}H-GABA uptake and GABA-IR were observed. In addition, GAD immunoreactive neurons contained GABA-IR as well. Extensive colocalization of {sup 3}H-glycine uptake and Gly-IR and that of {sup 3}H-GABA uptake, GABA-IR and perhaps GAD-IR were indicated by the similarities in the distribution, morphology and labeling frequency of neurons and lamination in the inner plexiform layer (IPL). However, the Gly-IR and the GABA-IR probes appeared to be more sensitive and can thus be a reliable marker for glycine and GABA containing neurons respectively.

  13. Genetic drift and rapid evolution of viviparity in insular fire salamanders (Salamandra salamandra)

    PubMed Central

    Velo-Antón, G; Zamudio, K R; Cordero-Rivera, A

    2012-01-01

    Continental islands offer an excellent opportunity to investigate adaptive processes and to time microevolutionary changes that precede macroevolutionary events. We performed a population genetic study of the fire salamander (Salamandra salamandra), a species that displays unique intraspecific diversity of reproductive strategies, to address the microevolutionary processes leading to phenotypic and genetic differentiation of island, coastal and interior populations. We used eight microsatellite markers to estimate genetic diversity, population structure and demographic parameters in viviparous insular populations and ovoviviparous coastal and interior populations. Our results show considerable genetic differentiation (FST range: 0.06–0.27), and no clear signs of gene flow among populations, except between the large and admixed interior populations. We find no support for island colonization by rafting or intentional/accidental anthropogenic introductions, indicating that rising sea levels were responsible for isolation of the island populations approximately 9000 years ago. Our study provides evidence of rapid genetic differentiation between island and coastal populations, and rapid evolution of viviparity driven by climatic selective pressures on island populations, geographic isolation with genetic drift, or a combination of these factors. Studies of these viviparous island populations in early stages of divergence help us better understand the microevolutionary processes involved in rapid phenotypic shifts. PMID:22086081

  14. Resistance to Chytridiomycosis in European Plethodontid Salamanders of the Genus Speleomantes

    PubMed Central

    Blooi, Mark; Tessa, Giulia; Bogaerts, Sergé; Sotgiu, Giuseppe; Garner, Trenton W. J.; Fisher, Matthew C.; Schmidt, Benedikt R.; Woeltjes, Tonnie; Beukema, Wouter; Bovero, Stefano; Adriaensen, Connie; Oneto, Fabrizio; Ottonello, Dario

    2013-01-01

    North America and the neotropics harbor nearly all species of plethodontid salamanders. In contrast, this family of caudate amphibians is represented in Europe and Asia by two genera, Speleomantes and Karsenia, which are confined to small geographic ranges. Compared to neotropical and North American plethodontids, mortality attributed to chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) has not been reported for European plethodontids, despite the established presence of Bd in their geographic distribution. We determined the extent to which Bd is present in populations of all eight species of European Speleomantes and show that Bd was undetectable in 921 skin swabs. We then compared the susceptibility of one of these species, Speleomantes strinatii, to experimental infection with a highly virulent isolate of Bd (BdGPL), and compared this to the susceptible species Alytes muletensis. Whereas the inoculated A. muletensis developed increasing Bd-loads over a 4-week period, none of five exposed S. strinatii were colonized by Bd beyond 2 weeks post inoculation. Finally, we determined the extent to which skin secretions of Speleomantes species are capable of killing Bd. Skin secretions of seven Speleomantes species showed pronounced killing activity against Bd over 24 hours. In conclusion, the absence of Bd in Speleomantes combined with resistance to experimental chytridiomycosis and highly efficient skin defenses indicate that the genus Speleomantes is a taxon unlikely to decline due to Bd. PMID:23703511

  15. Effects of egg size on success of larval salamanders in complex aquatic environments. [Ambystoma talpoideum

    SciTech Connect

    Semlitsch, R.D. ); Whitfield Gibbons, J. )

    1990-10-01

    Effects of egg size on growth, survival, and metamorphosis of larval salamanders (Ambystoma talpoideum) were examined in varying environments. Pond drying regime and presence vs. absence of an interspecific competitor were manipulated in a factorial experiment using artificial ponds to measure the responses of larvae. Females that were 4 yr old produced larger eggs and hatchlings than 1-yr-old females. Differences in body size at hatching persisted through day 49 of the experiment but disappeared by day 129. Drying regime also affected body size at day 49 but not at day 129. Larvae from large eggs, and larvae in constant water level ponds, had higher survival to day 129 than larvae from small eggs, and in drying ponds. There was also a significant interaction between egg size and drying regime. Larvae from large eggs survived better than larvae from small eggs in the constant water level ponds, but not in drying ponds. Interspecific competitors did not affect growth or survival to day 129. More individuals metamorphosed from drying ponds than from constant water level ponds. The growth advantages conferred by larger body size at hatching are transient and may disappear during compensatory growth later in the larval period. Body size advantages early in the larval period, however, probably account for increased survival through size-specific mechanisms at a time when newly hatched larvae are most vulnerable.

  16. Psychiatric morbidity after screening for breast cancer.

    PubMed Central

    Dean, C; Roberts, M M; French, K; Robinson, S

    1986-01-01

    One hundred and thirty two women with normal breast screening results were interviewed six months after their attendance at the Edinburgh Breast Screening Clinic. Eight percent of women said screening had made them more anxious about developing breast cancer. Thirty eight percent said they were more aware of the disease since screening but they regarded this as advantageous. Seventy percent of the women were still practising breast self-examination. There was no difference in the psychiatric morbidity of the screened sample when compared with a matched random sample community control group. Neither was there any difference in the General Health Questionnaire case rates before and after screening. Screening does not appear to increase the prevalence of psychiatric morbidity. Twenty nine percent of the interview sample were examining their breasts more than once a month--21% once a week or more. However, these frequent self-examiners did not have a greater prevalence of psychiatric morbidity than their matched controls. PMID:3711771

  17. Level of UV-B radiation influences the effects of glyphosate-based herbicide on the spotted salamander.

    PubMed

    Levis, Nicholas A; Johnson, Jarrett R

    2015-07-01

    Glyphosate-based herbicides are the number one pesticide in the United States and are used commonly around the world. Understanding the affects of glyphosate-based herbicides on non-target wildlife, for example amphibians, is critical for evaluation of regulations pertaining to the use of such herbicides. Additionally, it is important to understand how variation in biotic and abiotic environmental conditions, such as UV-B light regime, could potentially affect how glyphosate-based herbicides interact with non-target species. This study used artificial pond mesocosms to identify the effects of generic glyphosate-based herbicide (GLY-4 Plus) on mortality, cellular immune response, body size, and morphological plasticity of larvae of the spotted salamander (Ambystoma maculatum) under conditions that reflect moderate (UV(M)) and low (UV(L)) UV-B light regimes. Survival within a given UV-B level was unaffected by herbicide presence or absence. However, when herbicide was present, survival varied between UV-B levels with higher survival in UV(M) conditions. Herbicide presence in the UV(M) treatments also decreased body size and reduced cellular immune response. In the UV(L) treatments, the presence of herbicide increased body size and affected tail morphology. Finally, in the absence of herbicide, body size and cellular immune response were higher in UV(M) treatments compared to UV(L) treatments. Thus, the effects of herbicide on salamander fitness were dependent on UV-B level. As anthropogenic habitat modifications continue to alter landscapes that contain amphibian breeding ponds, salamanders may increasingly find themselves in locations with reduced canopy cover and increased levels of UV light. Our findings suggest that the probability of surviving exposure to the glyphosate-based herbicide used in this study may be elevated in more open canopy ponds, but the effects on other components of fitness may be varied and unexpected. PMID:25794558

  18. Detecting a hierarchical genetic population structure: the case study of the Fire Salamander (Salamandra salamandra) in Northern Italy

    PubMed Central

    Pisa, Giulia; Orioli, Valerio; Spilotros, Giulia; Fabbri, Elena; Randi, Ettore; Bani, Luciano

    2015-01-01

    The multistep method here applied in studying the genetic structure of a low dispersal and philopatric species, such as the Fire Salamander Salamandra salamandra, was proved to be effective in identifying the hierarchical structure of populations living in broad-leaved forest ecosystems in Northern Italy. In this study, 477 salamander larvae, collected in 28 sampling populations (SPs) in the Prealpine and in the foothill areas of Northern Italy, were genotyped at 16 specie-specific microsatellites. SPs showed a significant overall genetic variation (Global FST = 0.032, P < 0.001). The genetic population structure was assessed by using STRUCTURE 2.3.4. We found two main genetic groups, one represented by SPs inhabiting the Prealpine belt, which maintain connections with those of the Eastern foothill lowland (PEF), and a second group with the SPs of the Western foothill lowland (WF). The two groups were significantly distinct with a Global FST of 0.010 (P < 0.001). While the first group showed a moderate structure, with only one divergent SP (Global FST = 0.006, P < 0.001), the second group proved more structured being divided in four clusters (Global FST = 0.017, P = 0.058). This genetic population structure should be due to the large conurbations and main roads that separate the WF group from the Prealpine belt and the Eastern foothill lowland. The adopted methods allowed the analysis of the genetic population structure of Fire Salamander from wide to local scale, identifying different degrees of genetic divergence of their populations derived from forest fragmentation induced by urban and infrastructure sprawl. PMID:25691995

  19. Nuclear and mitochondrial multilocus phylogeny and survey of alkaloid content in true salamanders of the genus Salamandra (Salamandridae).

    PubMed

    Vences, Miguel; Sanchez, Eugenia; Hauswaldt, J Susanne; Eikelmann, Daniel; Rodríguez, Ariel; Carranza, Salvador; Donaire, David; Gehara, Marcelo; Helfer, Véronique; Lötters, Stefan; Werner, Philine; Schulz, Stefan; Steinfartz, Sebastian

    2014-04-01

    The genus Salamandra represents a clade of six species of Palearctic salamanders of either contrasted black-yellow, or uniformly black coloration, known to contain steroidal alkaloid toxins in high concentrations in their skin secretions. This study reconstructs the phylogeny of the genus Salamandra based on DNA sequences of segments of 10 mitochondrial and 13 nuclear genes from 31 individual samples representing all Salamandra species and most of the commonly recognized subspecies. The concatenated analysis of the complete dataset produced a fully resolved tree with most nodes strongly supported, suggesting that a clade composed of the Alpine salamander (S. atra) and the Corsican fire salamander (S. corsica) is the sister taxon to a clade containing the remaining species, among which S. algira and S. salamandra are sister species. Separate analyses of mitochondrial and nuclear data partitions disagreed regarding basal nodes and in the position of the root but concordantly recovered the S. atra/S. corsica as well as the S. salamandra/S. algira relationship. A species-tree analysis suggested almost simultaneous temporal splits between these pairs of species, which we hypothesize was caused by vicariance events after the Messinian salinity crisis (from late Miocene to early Pliocene). A survey of toxins with combined gas chromatography/mass spectroscopy confirmed the presence of samandarine and/or samandarone steroidal alkaloids in all species of Salamandra as well as in representatives of their sister group, Lyciasalamandra. Samandarone was also detected in lower concentrations in other salamandrids including Calotriton, Euproctus, Lissotriton, and Triturus, suggesting that the presence and possible biosynthesis of this alkaloid is plesiomorphic within the Salamandridae. PMID:24412216

  20. Toxicological responses of red-backed salamander (Plethodon cinereus) exposed to aged and amended soils containing lead.

    PubMed

    Bazar, Matthew A; Quinn, Michael J; Mozzachio, Kristie; Bleiler, John A; Archer, Christine R; Phillips, Carlton T; Johnson, Mark S

    2010-05-01

    The use of lead in military and civilian small arms projectiles is widely acknowledged to have resulted in high soil lead concentrations at many small arms ranges. These ranges are often adjacent to wildlife habitat or have become habitat when no longer used. To assess the potential toxicity of lead to terrestrial amphibians in contaminated areas, we exposed 100 red-backed salamanders (Plethodon cinereus) to either a control soil or one of four soil treatments amended with lead acetate for 28 days. Analytical mean soil concentrations were 14 (control), 553, 1700, 4700, and 9167 mg Pb/kg soil dry weight. An additional 60 salamanders were also exposed for 28 days to one of six field-collected soil samples from a small arms range and a skeet range. The field soil concentrations ranged from 11 (background) to 16,967 mg Pb/kg soil dry weight. Food consisted of uncontaminated flightless Drosophila melanogaster. Salamander survival was reduced in amended soil treatments of 4700 and 9167 mg/kg by 15% and 80%, respectively. Inappetence was observed at 4700 and 9167 mg/kg and growth decreased in the 9167 mg/kg treatment. Total white blood cells decreased 32% at 4700 mg/kg compared to controls and were 22% lower in the 9167 mg/kg treatment. In contrast, survival was 100% for all field-collected soils with no hematological effects. At 16,967 mg/kg there was evidence of soil avoidance and decreased growth. These data suggest marked differences in toxicity and bioavailability of the lead-amended soil in contrast to the field-collected soil containing lead. PMID:20135309

  1. Detecting a hierarchical genetic population structure: the case study of the Fire Salamander (Salamandra salamandra) in Northern Italy.

    PubMed

    Pisa, Giulia; Orioli, Valerio; Spilotros, Giulia; Fabbri, Elena; Randi, Ettore; Bani, Luciano

    2015-02-01

    The multistep method here applied in studying the genetic structure of a low dispersal and philopatric species, such as the Fire Salamander Salamandra salamandra, was proved to be effective in identifying the hierarchical structure of populations living in broad-leaved forest ecosystems in Northern Italy. In this study, 477 salamander larvae, collected in 28 sampling populations (SPs) in the Prealpine and in the foothill areas of Northern Italy, were genotyped at 16 specie-specific microsatellites. SPs showed a significant overall genetic variation (Global F ST = 0.032, P < 0.001). The genetic population structure was assessed by using STRUCTURE 2.3.4. We found two main genetic groups, one represented by SPs inhabiting the Prealpine belt, which maintain connections with those of the Eastern foothill lowland (PEF), and a second group with the SPs of the Western foothill lowland (WF). The two groups were significantly distinct with a Global F ST of 0.010 (P < 0.001). While the first group showed a moderate structure, with only one divergent SP (Global F ST = 0.006, P < 0.001), the second group proved more structured being divided in four clusters (Global F ST = 0.017, P = 0.058). This genetic population structure should be due to the large conurbations and main roads that separate the WF group from the Prealpine belt and the Eastern foothill lowland. The adopted methods allowed the analysis of the genetic population structure of Fire Salamander from wide to local scale, identifying different degrees of genetic divergence of their populations derived from forest fragmentation induced by urban and infrastructure sprawl. PMID:25691995

  2. Rapid fixation of non-native alleles revealed by genome-wide SNP analysis of hybrid tiger salamanders

    PubMed Central

    Fitzpatrick, Benjamin M; Johnson, Jarrett R; Kump, D Kevin; Shaffer, H Bradley; Smith, Jeramiah J; Voss, S Randal

    2009-01-01

    Background Hybrid zones represent valuable opportunities to observe evolution in systems that are unusually dynamic and where the potential for the origin of novelty and rapid adaptation co-occur with the potential for dysfunction. Recently initiated hybrid zones are particularly exciting evolutionary experiments because ongoing natural selection on novel genetic combinations can be studied in ecological time. Moreover, when hybrid zones involve native and introduced species, complex genetic patterns present important challenges for conservation policy. To assess variation of admixture dynamics, we scored a large panel of markers in five wild hybrid populations formed when Barred Tiger Salamanders were introduced into the range of California Tiger Salamanders. Results At three of 64 markers, introduced alleles have largely displaced native alleles within the hybrid populations. Another marker (GNAT1) showed consistent heterozygote deficits in the wild, and this marker was associated with embryonic mortality in laboratory F2's. Other deviations from equilibrium expectations were idiosyncratic among breeding ponds, consistent with highly stochastic demographic effects. Conclusion While most markers retain native and introduced alleles in expected proportions, strong selection appears to be eliminating native alleles at a smaller set of loci. Such rapid fixation of alleles is detectable only in recently formed hybrid zones, though it might be representative of dynamics that frequently occur in nature. These results underscore the variable and mosaic nature of hybrid genomes and illustrate the potency of recombination and selection in promoting variable, and often unpredictable genetic outcomes. Introgression of a few, strongly selected introduced alleles should not necessarily affect the conservation status of California Tiger Salamanders, but suggests that genetically pure populations of this endangered species will be difficult to maintain. PMID:19630983

  3. Calibrating abundance indices with population size estimators of red back salamanders (Plethodon cinereus) in a New England forest

    PubMed Central

    Ellison, Aaron M.; Jackson, Scott

    2015-01-01

    Herpetologists and conservation biologists frequently use convenient and cost-effective, but less accurate, abundance indices (e.g., number of individuals collected under artificial cover boards or during natural objects surveys) in lieu of more accurate, but costly and destructive, population size estimators to detect and monitor size, state, and trends of amphibian populations. Although there are advantages and disadvantages to each approach, reliable use of abundance indices requires that they be calibrated with accurate population estimators. Such calibrations, however, are rare. The red back salamander, Plethodon cinereus, is an ecologically useful indicator species of forest dynamics, and accurate calibration of indices of salamander abundance could increase the reliability of abundance indices used in monitoring programs. We calibrated abundance indices derived from surveys of P. cinereus under artificial cover boards or natural objects with a more accurate estimator of their population size in a New England forest. Average densities/m2 and capture probabilities of P. cinereus under natural objects or cover boards in independent, replicate sites at the Harvard Forest (Petersham, Massachusetts, USA) were similar in stands dominated by Tsuga canadensis (eastern hemlock) and deciduous hardwood species (predominantly Quercus rubra [red oak] and Acer rubrum [red maple]). The abundance index based on salamanders surveyed under natural objects was significantly associated with density estimates of P. cinereus derived from depletion (removal) surveys, but underestimated true density by 50%. In contrast, the abundance index based on cover-board surveys overestimated true density by a factor of 8 and the association between the cover-board index and the density estimates was not statistically significant. We conclude that when calibrated and used appropriately, some abundance indices may provide cost-effective and reliable measures of P. cinereus abundance that could

  4. Morbidity and Mortality in American Blacks.

    ERIC Educational Resources Information Center

    Henderson, Maureen; Cowan, Linda

    Comparisons are used in this paper to identify improvements in mortality and morbidity experiences over time, to identify new environmental hazards, and to emphasize the potential for improvement. The comparisons are presented in the full belief that racial variations are fundamentally socioeconomic variations. Efforts are also made to identify…

  5. Transvaginal appendectomy in morbidly obese patient.

    PubMed

    Yagci, Mehmet Ali; Kayaalp, Cuneyt; Ates, Mustafa

    2014-01-01

    Introduction. Laparoscopic appendectomy has significant benefits in obese patients. However, morbid obesity can be accepted as an exclusion criterion for natural orifice transluminal endoscopic surgery (NOTES). Here, we present a transvaginal appendectomy in a 66-year-old morbidly obese (BMI 36 kg/m(2), ASA III) patient. Case and Technique. Acute appendicitis was suspected based on history, physical examination, laboratory tests, and ultrasound findings. During laparoscopic surgery, a 5 mm trocar was inserted through the umbilicus and a 5 mm telescope was placed. A 12 mm trocar and a 5 mm grasper were inserted separately through the posterior fornix of the vagina under laparoscopic guidance. The appendix was divided with an endoscopic stapler through the transvaginal 12 mm trocar and removed from the same trocar. The operating time was 75 minutes with minimal blood loss (<10 mL). The patient was discharged 16 hours after surgery uneventfully and she did not require any analgesic administration. Conclusion. To the best of our knowledge, this is the first clinical case that focuses on the transvaginal appendectomy at morbid obesity. We can say that morbid obesity does not constitute an obstacle for treatment of acute appendicitis by transvaginal endoscopic surgery. PMID:25506028

  6. Co-Morbidity of Conditions among Prisoners

    ERIC Educational Resources Information Center

    Shinkfield, Alison J.; Graffam, J.; Meneilly, Sharn

    2009-01-01

    Eighty seven adult prisoners (58 males, 29 females) completed the Beck Depression Inventory (BDI-II), Beck Anxiety Inventory (BAI), and a questionnaire on current health in order to examine both the prevalence of co-morbid conditions and the relation of depression and anxiety to ill-health and prior substance use. High prevalence rates of…

  7. Morbidity and Infant Development: A Hypothesis.

    ERIC Educational Resources Information Center

    Pollitt, Ernesto

    1983-01-01

    Results of a study conducted in 14 villages of Sui Lin Township, Taiwan, suggest the hypothesis that, under conditions of extreme economic impoverishment and among children within populations where energy protein malnutrition is endemic, there is an inverse relationship between incidence of morbidity in infancy and measures of motor and mental…

  8. The morbid anatomy of high altitude

    PubMed Central

    Heath, Donald

    1979-01-01

    The morbid anatomical changes which take place in man and animals exposed to the chronic hypoxia of residence at high altitude are briefly reviewed. ImagesFig. 1Fig. 2Fig. 3Fig. 5Fig. 4Fig. 6Fig. 7Fig. 8 PMID:493205

  9. Perioperative morbidity of intracavitary gynecologic brachytherapy

    SciTech Connect

    Lanciano, R.; Corn, B.; Martin, E.; Schulthesis, T.; Hogan, W.M.; Rosenblum, N.

    1994-07-30

    The purpose was to define the incidence and severity of perioperative morbidity and its subsequent management with standard tandem and ovoid insertions to evaluate pretreatment and treatment factors associated with an increased risk of perioperative morbidity. Intraoperative complications were seen in 3% of implants and included two perforations and a vaginal laceration in two patients. Twenty-four percent of implants (16 patients) developed temperatures of > 100.5 (range 100.6 to 103), although only one patient required implant removal because of fever. Management of fever included antibiotics in 35% and acetaminophen only in 65%. Five implants were removed emergently secondary to presumed sepsis, exacerbation of chronic obstructive pulmonary disease, hypotension, change in mental status, and myocardial infarction/congestive heart failure. No patient developed a deep-vein thrombosis, pulmonary embolism, gastrointestinal obstruction, or died of a postoperative complication. Univariate analysis of pretreatment and treatment factors revealed older age and spinal/epidural anesthesia to be associated with increased perioperative morbidity, and older age and higher ASA classification to be associated with severe complications requiring removal of implant. Multivariate analysis revealed only older age to be significantly related to perioperative morbidity. Fever of > 100.5 was seen in 24% of implants and can be managed successfully without removal of the implant in 96% of cases. Use of antibiotics preoperatively and intraoperatively did not reduce the risk of perioperative temperature elevation. Use of routine diphenoxylate hydrochloride prophylaxis was tolerated without ileus or gastrointestinal obstruction clinically. Although routine deep-vein thrombosis prophylaxis is reasonable, the data would support a low risk of deep-vein thrombosis for untreated patients. Severe perioperative morbidity necessitated premature implant removal in only 5% of cases. 24 refs., 2 tabs.

  10. Effect of co-morbidities on fracture risk: Findings from the Global Longitudinal Study of Osteoporosis in Women (GLOW)

    PubMed Central

    Dennison, Elaine M.; Compston, Juliet E.; Flahive, Julie; Siris, Ethel S.; Gehlbach, Stephen H.; Adachi, Jonathan D.; Boonen, Steven; Chapurlat, Roland; Díez-Pérez, Adolfo; Anderson, Frederick A.; Hooven, Frederick H.; LaCroix, Andrea Z.; Lindsay, Robert; Netelenbos, J. Coen; Pfeilschifter, Johannes; Rossini, Maurizio; Roux, Christian; Saag, Kenneth G.; Sambrook, Philip; Silverman, Stuart; Watts, Nelson B.; Greenspan, Susan L.; Premaor, Melissa; Cooper, Cyrus

    2016-01-01

    Introduction Greater awareness of the relationship between co-morbidities and fracture risk may improve fracture-prediction algorithms such as FRAX. Materials and methods We used a large, multinational cohort study (GLOW) to investigate the effect of co-morbidities on fracture risk. Women completed a baseline questionnaire detailing past medical history, including co-morbidity history and fracture. They were re-contacted annually to determine incident clinical fractures. A co-morbidity index, defined as number of baseline co-morbidities, was derived. The effect of adding the co-morbidity index to FRAX risk factors on fracture prevention was examined using chi-squared tests, the May-Hosmer test, c index and comparison of predicted versus observed fracture rates. Results Of 52,960 women with follow-up data, enrolled between October 2006 and February 2008, 3224 (6.1%) sustained an incident fracture over 2 years. All recorded co-morbidities were significantly associated with fracture, except for high cholesterol, hypertension, celiac disease, and cancer. The strongest association was seen with Parkinson’s disease (age-adjusted hazard ratio [HR]: 2.2; 95% CI: 1.6–3.1; P<0.001). Co-morbidities that contributed most to fracture prediction in a Cox regression model with FRAX risk factors as additional predictors were: Parkinson’s disease, multiple sclerosis, chronic obstructive pulmonary disease, osteoarthritis, and heart disease. Conclusion Co-morbidities, as captured in a co-morbidity index, contributed significantly to fracture risk in this study population. Parkinson’s disease carried a particularly high risk of fracture; and increasing co-morbidity index was associated with increasing fracture risk. Addition of co-morbidity index to FRAX risk factors improved fracture prediction. PMID:22426498

  11. Current and Historical Drivers of Landscape Genetic Structure Differ in Core and Peripheral Salamander Populations

    PubMed Central

    Dudaniec, Rachael Y.; Spear, Stephen F.; Richardson, John S.; Storfer, Andrew

    2012-01-01

    With predicted decreases in genetic diversity and greater genetic differentiation at range peripheries relative to their cores, it can be difficult to distinguish between the roles of current disturbance versus historic processes in shaping contemporary genetic patterns. To address this problem, we test for differences in historic demography and landscape genetic structure of coastal giant salamanders (Dicamptodon tenebrosus) in two core regions (Washington State, United States) versus the species' northern peripheral region (British Columbia, Canada) where the species is listed as threatened. Coalescent-based demographic simulations were consistent with a pattern of post-glacial range expansion, with both ancestral and current estimates of effective population size being much larger within the core region relative to the periphery. However, contrary to predictions of recent human-induced population decline in the less genetically diverse peripheral region, there was no genetic signature of population size change. Effects of current demographic processes on genetic structure were evident using a resistance-based landscape genetics approach. Among core populations, genetic structure was best explained by length of the growing season and isolation by resistance (i.e. a ‘flat’ landscape), but at the periphery, topography (slope and elevation) had the greatest influence on genetic structure. Although reduced genetic variation at the range periphery of D. tenebrosus appears to be largely the result of biogeographical history rather than recent impacts, our analyses suggest that inherent landscape features act to alter dispersal pathways uniquely in different parts of the species' geographic range, with implications for habitat management. PMID:22590604

  12. Dynamics and thermal sensitivity of ballistic and non-ballistic feeding in salamanders.

    PubMed

    Deban, Stephen M; Scales, Jeffrey A

    2016-02-01

    Low temperature reduces the performance of muscle-powered movements, but in movements powered by elastic recoil mechanisms, this effect can be mitigated and performance can be increased. To better understand the morphological basis of high performance and thermal robustness of elastically powered movements, we compared feeding dynamics at a range of temperatures (5-25°C) in two species of terrestrial plethodontid salamanders, Plethodon metcalfi and Ensatina eschscholtzii, which differ in tongue muscle architecture and the mechanism of tongue projection. We found that Ensatina is capable of ballistic projection with a mean muscle mass-specific power of 2100 W kg(-1), revealing an elastic mechanism. Plethodon, in contrast, projected its tongue non-ballistically with a mean power of only 18 W kg(-1), indicating it is muscle powered. Ensatina projected its tongue significantly farther than Plethodon and with dynamics that had significantly lower thermal sensitivity at temperatures below 15°C. These performance differences were correlated with morphological differences, namely elongated collagenous aponeuroses in the projector muscle of Ensatina as compared with Plethodon, which are likely the site of energy storage, and the absence in Ensatina of projector muscle fibers attaching to the tongue skeleton that allows projection to be truly ballistic. These findings demonstrate that, in these otherwise similar species, the presence in one species of elaborated connective tissue in series with myofibers confers not only 10-fold greater absolute performance but also greater thermal robustness of performance. We conclude that changes in muscle and connective tissue architecture are sufficient to alter significantly the mechanics, performance and thermal robustness of musculoskeletal systems. PMID:26612894

  13. Ecological connectivity assessment in a strongly structured fire salamander (Salamandra salamandra) population

    PubMed Central

    Bani, Luciano; Pisa, Giulia; Luppi, Massimiliano; Spilotros, Giulia; Fabbri, Elena; Randi, Ettore; Orioli, Valerio

    2015-01-01

    Small populations are more prone to extinction if the dispersal among them is not adequately maintained by ecological connections. The degree of isolation between populations could be evaluated measuring their genetic distance, which depends on the respective geographic (isolation by distance, IBD) and/or ecological (isolation by resistance, IBR) distances. The aim of this study was to assess the ecological connectivity of fire salamander Salamandra salamandra populations by means of a landscape genetic approach. The species lives in broad-leaved forest ecosystems and is particularly affected by fragmentation due to its habitat selectivity and low dispersal capability. We analyzed 477 biological samples collected in 47 sampling locations (SLs) in the mainly continuous populations of the Prealpine and Eastern foothill lowland (PEF) and 10 SLs in the fragmented populations of the Western foothill (WF) lowland of Lombardy (northern Italy). Pairwise genetic distances (Chord distance, DC) were estimated from allele frequencies of 16 microsatellites loci. Ecological distances were calculated using one of the most promising methodology in landscape genetics studies, the circuit theory, applied to habitat suitability maps. We realized two habitat suitability models: one without barriers (EcoD) and a second one accounting for the possible barrier effect of main roads (EcoDb). Mantel tests between distance matrices highlighted how the Log-DC in PEF populations was related to log-transformed geographic distance (confirming a prevalence of IBD), while it was explained by the Log-EcoD, and particularly by the Log-EcoDb, in WF populations, even when accounting for the confounding effect of geographic distance (highlighting a prevalence of IBR). Moreover, we also demonstrated how considering the overall population, the effect of Euclidean or ecological distances on genetic distances acting at the level of a single group (PEF or WF populations) could not be detected, when

  14. Delayed life history effects, multilevel selection, and evolutionary trade-offs in the California tiger salamander.

    PubMed

    Searcy, Christopher A; Gray, Levi N; Trenham, Peter C; Shaffer, H Bradley

    2014-01-01

    Delayed life history effects (DLHEs) occur when fitness in one life stage affects fitness in subsequent life stages. Given their biphasic life cycle, pond-breeding amphibians provide a natural system for studying DLHEs, although these effects are not restricted to species with biphasic life histories. In this study, we used multiple mark-recapture techniques enabled by a large trapping array to monitor components of fitness and resulting DLHEs in a population of the endangered California tiger salamander (Ambystoma californiense). We found that DLHEs are prominent across all life stage transitions and that there is variation in whether selection acts primarily at the individual or cohort level. We also demonstrated that there is more than an order of magnitude variation in mean cohort fitness, providing tremendous variation for DLHEs to act upon. We documented an evolutionary trade-off between mass at emergence and date of emergence, which may play a role in maintaining the variation in mass (fitness) at emergence. A literature review revealed that such high levels of intercohort variation occur in many other pond-breeding amphibians, and that appropriately documenting the magnitude of intercohort variation requires long-term studies (roughly two population turnovers). Given the profound effect that DLHEs can have on population dynamics, quantifying intercohort variation in mean fitness and the level(s) at which selection acts will be very important for developing accurate models of population dynamics. In general, when developing models of population dynamics, more attention should be paid to variation in mean fitness and not just variation in total numbers. PMID:24649647

  15. Coexpression of three opsins in cone photoreceptors of the salamander Ambystoma tigrinum.

    PubMed

    Isayama, Tomoki; Chen, Ying; Kono, Masahiro; Fabre, Eduard; Slavsky, Michael; DeGrip, Willem J; Ma, Jian-Xing; Crouch, Rosalie K; Makino, Clint L

    2014-07-01

    Although more than one type of visual opsin is present in the retina of most vertebrates, it was thought that each type of photoreceptor expresses only one opsin. However, evidence has accumulated that some photoreceptors contain more than one opsin, in many cases as a result of a developmental transition from the expression of one opsin to another. The salamander UV-sensitive (UV) cone is particularly notable because it contains three opsins (Makino and Dodd [1996] J Gen Physiol 108:27-34). Two opsin types are expressed at levels more than 100 times lower than the level of the primary opsin. Here, immunohistochemical experiments identified the primary component as a UV cone opsin and the two minor components as the short wavelength-sensitive (S) and long wavelength-sensitive (L) cone opsins. Based on single-cell recordings of 156 photoreceptors, the presence of three components in UV cones of hatchlings and terrestrial adults ruled out a developmental transition. There was no evidence for multiple opsin types within rods or S cones, but immunohistochemistry and partial bleaching in conjunction with single-cell recording revealed that both single and double L cones contained low levels of short wavelength-sensitive pigments in addition to the main L visual pigment. These results raise the possibility that coexpression of multiple opsins in other vertebrates was overlooked because a minor component absorbing at short wavelengths was masked by the main visual pigment or because the expression level of a component absorbing at long wavelengths was exceedingly low. PMID:24374736

  16. Abundance and phenology patterns of two pond-breeding salamanders determine species interactions in natural populations.

    PubMed

    Anderson, Thomas L; Hocking, Daniel J; Conner, Christopher A; Earl, Julia E; Harper, Elizabeth B; Osbourn, Michael S; Peterman, William E; Rittenhouse, Tracy A G; Semlitsch, Raymond D

    2015-03-01

    Phenology often determines the outcome of interspecific interactions, where early-arriving species often dominate interactions over those arriving later. The effects of phenology on species interactions are especially pronounced in aquatic systems, but the evidence is largely derived from experimental studies. We examined whether differences in breeding phenology between two pond-breeding salamanders (Ambystoma annulatum and A. maculatum) affected metamorph recruitment and demographic traits within natural populations, with the expectation that the fall-breeding A. annulatum would negatively affect the spring-breeding A. maculatum. We monitored populations of each species at five ponds over 4 years using drift fences. Metamorph abundance and survival of A. annulatum were affected by intra- and interspecific processes, whereas metamorph size and date of emigration were primarily influenced by intraspecific effects. Metamorph abundance, snout-vent length, date of emigration and survival for A. maculatum were all predicted by combinations of intra- and interspecific effects, but often showed negative relationships with A. annulatum metamorph traits and abundance. Size and date of metamorphosis were strongly correlated within each species, but in opposite patterns (negative for A. annulatum and positive for A. maculatum), suggesting that the two species use alternative strategies to enhance terrestrial survival and that these factors may influence their interactions. Our results match predictions from experimental studies that suggest recruitment is influenced by intra- and interspecific processes which are determined by phenological differences between species. Incorporating spatiotemporal variability when modeling population dynamics is necessary to understand the importance of phenology in species interactions, especially as shifts in phenology occur under climate change. PMID:25413866

  17. Ecological connectivity assessment in a strongly structured fire salamander (Salamandra salamandra) population.

    PubMed

    Bani, Luciano; Pisa, Giulia; Luppi, Massimiliano; Spilotros, Giulia; Fabbri, Elena; Randi, Ettore; Orioli, Valerio

    2015-08-01

    Small populations are more prone to extinction if the dispersal among them is not adequately maintained by ecological connections. The degree of isolation between populations could be evaluated measuring their genetic distance, which depends on the respective geographic (isolation by distance, IBD) and/or ecological (isolation by resistance, IBR) distances. The aim of this study was to assess the ecological connectivity of fire salamander Salamandra salamandra populations by means of a landscape genetic approach. The species lives in broad-leaved forest ecosystems and is particularly affected by fragmentation due to its habitat selectivity and low dispersal capability. We analyzed 477 biological samples collected in 47 sampling locations (SLs) in the mainly continuous populations of the Prealpine and Eastern foothill lowland (PEF) and 10 SLs in the fragmented populations of the Western foothill (WF) lowland of Lombardy (northern Italy). Pairwise genetic distances (Chord distance, DC) were estimated from allele frequencies of 16 microsatellites loci. Ecological distances were calculated using one of the most promising methodology in landscape genetics studies, the circuit theory, applied to habitat suitability maps. We realized two habitat suitability models: one without barriers (EcoD) and a second one accounting for the possible barrier effect of main roads (EcoDb). Mantel tests between distance matrices highlighted how the Log-DC in PEF populations was related to log-transformed geographic distance (confirming a prevalence of IBD), while it was explained by the Log-EcoD, and particularly by the Log-EcoDb, in WF populations, even when accounting for the confounding effect of geographic distance (highlighting a prevalence of IBR). Moreover, we also demonstrated how considering the overall population, the effect of Euclidean or ecological distances on genetic distances acting at the level of a single group (PEF or WF populations) could not be detected, when

  18. Variation in Salamander Tail Regeneration Is Associated with Genetic Factors That Determine Tail Morphology

    PubMed Central

    Voss, Gareth J.; Kump, D. Kevin; Walker, John A.; Voss, S. Randal

    2013-01-01

    Very little is known about the factors that cause variation in regenerative potential within and between species. Here, we used a genetic approach to identify heritable genetic factors that explain variation in tail regenerative outgrowth. A hybrid ambystomatid salamander (Ambystoma mexicanum x A. andersoni) was crossed to an A. mexicanum and 217 offspring were induced to undergo metamorphosis and attain terrestrial adult morphology using thyroid hormone. Following metamorphosis, each salamander’s tail tip was amputated and allowed to regenerate, and then amputated a second time and allowed to regenerate. Also, DNA was isolated from all individuals and genotypes were determined for 187 molecular markers distributed throughout the genome. The area of tissue that regenerated after the first and second amputations was highly positively correlated across males and females. Males presented wider tails and regenerated more tail tissue during both episodes of regeneration. Approximately 66–68% of the variation in regenerative outgrowth was explained by tail width, while tail length and genetic sex did not explain a significant amount of variation. A small effect QTL was identified as having a sex-independent effect on tail regeneration, but this QTL was only identified for the first episode of regeneration. Several molecular markers significantly affected regenerative outgrowth during both episodes of regeneration, but the effect sizes were small (<4%) and correlated with tail width. The results show that ambysex and minor effect QTL explain variation in adult tail morphology and importantly, tail width. In turn, tail width at the amputation plane largely determines the rate of regenerative outgrowth. Because amputations in this study were made at approximately the same position of the tail, our results resolve an outstanding question in regenerative biology: regenerative outgrowth positively co-varies as a function of tail width at the amputation site. PMID:23843997

  19. Co-expression of three opsins in cone photoreceptors of the salamander, Ambystoma tigrinum

    PubMed Central

    Isayama, Tomoki; Chen, Ying; Kono, Masahiro; Fabre, Eduard; Slavsky, Michael; DeGrip, Willem J.; Ma, Jian-Xing; Crouch, Rosalie K.; Makino, Clint L.

    2014-01-01

    Whereas more than one type of visual opsin is present in the retina of most vertebrates, it was thought that each type of photoreceptor expressed only one opsin. However, evidence has accumulated that some photoreceptors contain more than one opsin, in many cases as a result of a developmental transition from the expression of one opsin to another. The salamander UV-sensitive (UV) cone is particularly notable because it contains three opsins (Makino and Dodd, 1996; J Gen Physiol 108:27–34). Two opsin types are expressed at levels more than a hundred times lower than that of the primary opsin. Here, immunohistochemical experiments identified the primary component as a UV cone opsin and the two minor components as the short wavelength-sensitive (S) and long wavelength-sensitive (L) cone opsins. Based on single cell recordings of 156 photoreceptors, the presence of three components in UV cones of hatchlings and terrestrial adults ruled out a developmental transition. There was no evidence for multiple opsin types within rods or S cones. But immunohistochemistry and partial bleaching in conjunction with single cell recording revealed that both single and double L cones contained low levels of short wavelength-sensitive pigments in addition to the main L visual pigment. These results raise the possibility that co-expression of multiple opsins in other vertebrates was overlooked because a minor component absorbing at short wavelengths was masked by the main visual pigment or because the expression level of a component absorbing at long wavelengths was exceedingly low. PMID:24374736

  20. Is the blind cave salamander Proteus anguinus equiped for magnetic orientation ?

    NASA Astrophysics Data System (ADS)

    Bouquerel, H.; Valet, J. P.

    2003-04-01

    The Proteus anguinus is a blind cave salamander which can develop the ability of using the earth’s magnetic field for orientation and navigation. It has been shown that the strength of the geomagnetic field is not strong enough to excite the electroreceptors of these animals through induction mechanism so that the most likely hypothesis is that they would use cristals of magnetite as permanent magnets. We have been looking for evidence of remanent magnetism in several proteus collected from the underground CNRS laboratory at Moulis (France). Because the level of natural remanent magnetization, if any, was too low to be measured with confidence using a 3 axis squid 2G magnetometer (even bringing the animals as close as possible to the sensors), we stepwise remagnetized the samples between 0.2 and 1.2T. Measurements were performed in different parts of three proteus bodies. No significant magnetization was detected in the head, most of the signal being concentrated in the lower body of the animal. Saturation was attained after 0.2T while stepwise demagnetization by alternating field showed that most magnetization was removed after 40 mT (medium destructive field, MDF of about 10 mT), which is typical of magnetite. Independent measurements of clay soils taken from the surrounding immediate environment of the animals reveal a different magnetic signature for saturation, MDF and viscosity. Thus there is no apparent and direct link between food absorbed from their environment and the magnetic remamence of the animals. New experiments are currently in progress to determine whether magnetite is the unique magnetic carrier and also to provide better clue about the magnetic granulometry and its distribution.

  1. Parallel evolution of character displacement driven by competitive selection in terrestrial salamanders

    PubMed Central

    2010-01-01

    Background Parallel evolution can occur when common environmental factors exert similar selective forces on morphological variation in populations in different geographic localities. Competition can also generate morphological shifts, and if competing species co-occur in multiple geographic regions, then repeated instances of competitively-driven morphological divergence (character displacement) can occur. Despite the importance of character displacement for inferring the role of selection in morphological evolution however, replicated instances of sympatric morphological divergence are understudied. Results I tested the hypothesis that interspecific competition generated patterns of parallel morphological divergence in multiple geographic locations where two competing salamander species, Plethodon jordani and P. teyahalee, come into contact. I used geometric morphometrics to characterize head shape and found ecological character displacement in sympatric localities on each of three distinct mountains (geographic transects), where sympatric specimens displayed greater cranial differences and an increase in cranial robustness as compared to allopatric specimens. Using a recently developed analytical procedure, I also found that the observed morphological evolution within each species was consistent among transects; both in the total amount of morphological change as well as the direction of evolution in the morphological data space. This provided strong statistical evidence of parallel morphological evolution within species across replicate geographic transects. Conclusions The results presented here reveal that the morphological evolution of each species followed a common evolutionary path in each transect. Because dispersal between sympatric locations among transects is unlikely, these findings suggest that the repeated instances of character displacement have evolved in situ. They also suggest that selection from competitive interactions plays an important role

  2. Physiological and morphological characterization of ganglion cells in the salamander retina.

    PubMed

    Wang, Jing; Jacoby, Roy; Wu, Samuel M

    2016-02-01

    Retinal ganglion cells (RGCs) integrate visual information from the retina and transmit collective signals to the brain. A systematic investigation of functional and morphological characteristics of various types of RGCs is important to comprehensively understand how the visual system encodes and transmits information via various RGC pathways. This study evaluated both physiological and morphological properties of 67 RGCs in dark-adapted flat-mounted salamander retina by examining light-evoked cation and chloride current responses via voltage-clamp recordings and visualizing morphology by Lucifer yellow fluorescence with a confocal microscope. Six groups of RGCs were described: asymmetrical ON-OFF RGCs, symmetrical ON RGCs, OFF RGCs, and narrow-, medium- and wide-field ON-OFF RGCs. Dendritic field diameters of RGCs ranged 102-490 μm: narrow field (<200 μm, 31% of RGCs), medium field (200-300 μm, 45%) and wide field (>300 μm, 24%). Dendritic ramification patterns of RGCs agree with the sublamina A/B rule. 34% of RGCs were monostratified, 24% bistratified and 42% diffusely stratified. 70% of ON RGCs and OFF RGCs were monostratified. Wide-field RGCs were diffusely stratified. 82% of RGCs generated light-evoked ON-OFF responses, while 11% generated ON responses and 7% OFF responses. Response sensitivity analysis suggested that some RGCs obtained separated rod/cone bipolar cell inputs whereas others obtained mixed bipolar cell inputs. 25% of neurons in the RGC layer were displaced amacrine cells. Although more types may be defined by more refined classification criteria, this report is to incorporate more physiological properties into RGC classification. PMID:26731645

  3. Ontogenetic convergence and evolution of foot morphology in European cave salamanders (Family: Plethodontidae)

    PubMed Central

    2010-01-01

    Background A major goal in evolutionary biology is to understand the evolution of phenotypic diversity. Both natural and sexual selection play a large role in generating phenotypic adaptations, with biomechanical requirements and developmental mechanisms mediating patterns of phenotypic evolution. For many traits, the relative importance of selective and developmental components remains understudied. Results We investigated ontogenetic trajectories of foot morphology in the eight species of European plethodontid cave salamander to test the hypothesis that adult foot morphology was adapted for climbing. Using geometric morphometrics and other approaches, we found that developmental patterns in five species displayed little morphological change during growth (isometry), where the extensive interdigital webbing in adults was best explained as the retention of the juvenile morphological state. By contrast, three species exhibited significant allometry, with an increase in interdigital webbing during growth. Phylogenetic analyses revealed that multiple evolutionary transitions between isometry and allometry of foot webbing have occurred in this lineage. Allometric parameters of foot growth were most similar to those of a tropical species previously shown to be adapted for climbing. Finally, interspecific variation in adult foot morphology was significantly reduced as compared to variation among juveniles, indicating that ontogenetic convergence had resulted in a common adult foot morphology across species. Conclusions The results presented here provide evidence of a complex history of phenotypic evolution in this clade. The common adult phenotype exhibited among species reveals that selection plays an important part in generating patterns of foot diversity in the group. However, developmental trajectories arriving at this common morphology are distinct; with some species displaying developmental stasis (isometry), while others show an increase in foot webbing during

  4. Effects of Photoperiod and Temperature on Growth and Development in Clouded Salamander (Hynobius nebulosus) Larvae.

    PubMed

    Kukita, Sayuri; Gouda, Mika; Ikeda, Sakiko; Ishibashi, Sakiko; Furuya, Tatsunori; Nakamura, Keiji

    2015-06-01

    Day length is one of the most important factors that organisms use to predict seasonal changes in their environment. Several amphibians regulate their growth and development in response to photoperiod. However, many studies have not focused on the ecological effects of the photoperiodic response on growth and development because they use tropical animals, animals from a commercial source or from unknown localities, or extreme light regimens for experiments. In the present study, we examined the effects of photoperiod on growth and development in the clouded salamander (Hynobius nebulosus) by raising larvae under different photoperiods and at different temperatures in the laboratory. The average larval period under a long-day photoperiod of L16:D8 was longer than that under L12:D12 at 15°C or 20°C, although the difference between the photoperiods was only significant for 15°C. Juveniles weighed more at metamorphosis under L16:D8 than those under L12:D12, irrespective of temperature, suggesting that a longer developmental period results in a heavier body weight. The head width of juveniles did not differ for different photoperiods at either temperature. However, the growth rate of the head width under L12:D12 was faster than that under L16:D8 at 15°C. Long day length appears to produce larger H. nebulosus juveniles in a relatively stable aquatic environment with a low population density. Thus, development may be accelerated when the day length becomes shorter as winter approaches, and larvae may have increased the growth rate of their head widths to compensate for the shorter growing period under shorter day lengths. PMID:26003982

  5. Obstetric Care Consensus No 5 Summary: Severe Maternal Morbidity: Screening And Review.

    PubMed

    2016-09-01

    This document builds upon recommendations from peer organizations and outlines a process for identifying maternal cases that should be reviewed. Severe maternal morbidity is associated with a high rate of preventability, similar to that of maternal mortality. It also can be considered a near miss for maternal mortality because without identification and treatment, in some cases, these conditions would lead to maternal death. Identifying severe morbidity is, therefore, important for preventing such injuries that lead to mortality and for highlighting opportunities to avoid repeat injuries. The two-step screen and review process described in this document is intended to efficiently detect severe maternal morbidity in women and to ensure that each case undergoes a review to determine whether there were opportunities for improvement in care. Like cases of maternal mortality, cases of severe maternal morbidity merit quality review. In the absence of consensus on a comprehensive list of conditions that represent severe maternal morbidity, institutions and systems should either adopt an existing screening criteria or create their own list of outcomes that merit review. PMID:27548549

  6. Obstetric Care Consensus No. 5: Severe Maternal Morbidity: Screening and Review.

    PubMed

    2016-09-01

    This document builds upon recommendations from peer organizations and outlines a process for identifying maternal cases that should be reviewed. Severe maternal morbidity is associated with a high rate of preventability, similar to that of maternal mortality. It also can be considered a near miss for maternal mortality because without identification and treatment, in some cases, these conditions would lead to maternal death. Identifying severe morbidity is, therefore, important for preventing such injuries that lead to mortality and for highlighting opportunities to avoid repeat injuries. The two-step screen and review process described in this document is intended to efficiently detect severe maternal morbidity in women and to ensure that each case undergoes a review to determine whether there were opportunities for improvement in care. Like cases of maternal mortality, cases of severe maternal morbidity merit quality review. In the absence of consensus on a comprehensive list of conditions that represent severe maternal morbidity, institutions and systems should either adopt an existing screening criteria or create their own list of outcomes that merit review. PMID:27548555

  7. Myocardial ischemia--association with perioperative cardiac morbidity.

    PubMed Central

    Cunningham, A. J.

    1993-01-01

    The development of ambulatory electrocardiographic recorders and analysers and the application of transesophageal echocardiography in the mid-1980's enabled investigators to quantify and describe the occurrence of silent as well as symptomatic ischemia in the perioperative period. Several technical advances which have recently occurred in ECG monitoring include the use of miniaturized digital computing equipment to store and analyze data. In addition, real time ST-segment analysis has become widely available on multicomponent monitors in both the operating room and intensive care units. The incidence of perioperative myocardial ischemia depends on the patient population, the surgical procedure, and the monitoring technique used. Several studies in the early 1990's have shown that cardiac morbidity in patients undergoing major, noncardiac surgery is best predicted by postoperative myocardial ischemia, rather than tradition preoperative clinical predictors. Long duration postoperative ischemia may be the factor most significantly associated with adverse cardiac outcome. Postoperative pain, physiological and emotional stress may all combine to cause tachycardia, hypertension, increase in cardiac output, and fluid shifts which, in high risk patients, might result in subendocardial ischemia and eventual myocardial infarction. If postoperative myocardial ischemia is the cause of late postoperative myocardial infarction in patients undergoing non-cardiac surgery, then treatment of postoperative myocardial ischemia should reduce morbidity. In addition, reducing pain and stress and avoiding postoperative hypoxemia might prevent postoperative myocardial ischemia and minimize the need for extensive preoperative cardiac evaluation. PMID:7825338

  8. "Vicious circles": the development of morbid obesity.

    PubMed

    Owen-Smith, Amanda; Donovan, Jenny; Coast, Joanna

    2014-09-01

    Although there has been extensive research around the etiology of moderate obesity, there are still important questions relating to the development and lived experience of extreme obesity. We present a synthesis of data from two in-depth qualitative studies in which morbidly obese participants (N = 31) were able to explain the development of the condition in their own terms. We identified consistent themes in the two datasets, and undertook a detailed data synthesis. Particularly salient themes in the development of morbid obesity related to family structures and early socialization experiences, and the role of emotional distress was dominant in both initial weight gain and ongoing cycles of loss and regain. All informants accepted some responsibility for their health state, but identified a number of mitigating factors that limited personal culpability that were often related to the fulfillment of gendered social expectations. PMID:25079501

  9. Factors Affecting Morbidity in Solid Organ Injuries

    PubMed Central

    Baygeldi, Serdar; Karakose, Oktay; Özcelik, Kazım Caglar; Pülat, Hüseyin; Damar, Sedat; Eken, Hüseyin; Zihni, İsmail; Çalta, Alpaslan Fedai; Baç, Bilsel

    2016-01-01

    Background and Aim. The aim of this study was to investigate the effects of demographic characteristics, biochemical parameters, amount of blood transfusion, and trauma scores on morbidity in patients with solid organ injury following trauma. Material and Method. One hundred nine patients with solid organ injury due to abdominal trauma during January 2005 and October 2015 were examined retrospectively in the General Surgery Department of Dicle University Medical Faculty. Patients' age, gender, trauma interval time, vital status (heart rate, arterial tension, and respiratory rate), hematocrit (HCT) value, serum area aminotransferase (ALT) and aspartate aminotransferase (AST) values, presence of free abdominal fluid in USG, trauma mechanism, extra-abdominal system injuries, injured solid organs and their number, degree of injury in abdominal CT, number of blood transfusions, duration of hospital stay, time of operation (for those undergoing operation), trauma scores (ISS, RTS, Glasgow coma scale, and TRISS), and causes of morbidity and mortality were examined. In posttraumatic follow-up period, intra-abdominal hematoma infection, emboli, catheter infection, and deep vein thrombosis were monitored as factors of morbidity. Results. One hundred nine patients were followed up and treated due to isolated solid organ injury following abdominal trauma. There were 81 males (74.3%) and 28 females (25.7%), and the mean age was 37.6 ± 18.28 (15–78) years. When examining the mechanism of abdominal trauma in patients, the following results were obtained: 58 (53.3%) traffic accidents (22 out-vehicle and 36 in-vehicle), 27 (24.7%) falling from a height, 14 (12.9%) assaults, 5 (4.5%) sharp object injuries, and 5 (4.5%) gunshot injuries. When evaluating 69 liver injuries scaled by CT the following was detected: 14 (20.3%) of grade I, 32 (46.4%) of grade II, 22 (31.8%) of grade III, and 1 (1.5%) of grade IV. In 63 spleen injuries scaled by CT the following was present: grade I in

  10. Factors Affecting Morbidity in Solid Organ Injuries.

    PubMed

    Baygeldi, Serdar; Karakose, Oktay; Özcelik, Kazım Caglar; Pülat, Hüseyin; Damar, Sedat; Eken, Hüseyin; Zihni, İsmail; Çalta, Alpaslan Fedai; Baç, Bilsel

    2016-01-01

    Background and Aim. The aim of this study was to investigate the effects of demographic characteristics, biochemical parameters, amount of blood transfusion, and trauma scores on morbidity in patients with solid organ injury following trauma. Material and Method. One hundred nine patients with solid organ injury due to abdominal trauma during January 2005 and October 2015 were examined retrospectively in the General Surgery Department of Dicle University Medical Faculty. Patients' age, gender, trauma interval time, vital status (heart rate, arterial tension, and respiratory rate), hematocrit (HCT) value, serum area aminotransferase (ALT) and aspartate aminotransferase (AST) values, presence of free abdominal fluid in USG, trauma mechanism, extra-abdominal system injuries, injured solid organs and their number, degree of injury in abdominal CT, number of blood transfusions, duration of hospital stay, time of operation (for those undergoing operation), trauma scores (ISS, RTS, Glasgow coma scale, and TRISS), and causes of morbidity and mortality were examined. In posttraumatic follow-up period, intra-abdominal hematoma infection, emboli, catheter infection, and deep vein thrombosis were monitored as factors of morbidity. Results. One hundred nine patients were followed up and treated due to isolated solid organ injury following abdominal trauma. There were 81 males (74.3%) and 28 females (25.7%), and the mean age was 37.6 ± 18.28 (15-78) years. When examining the mechanism of abdominal trauma in patients, the following results were obtained: 58 (53.3%) traffic accidents (22 out-vehicle and 36 in-vehicle), 27 (24.7%) falling from a height, 14 (12.9%) assaults, 5 (4.5%) sharp object injuries, and 5 (4.5%) gunshot injuries. When evaluating 69 liver injuries scaled by CT the following was detected: 14 (20.3%) of grade I, 32 (46.4%) of grade II, 22 (31.8%) of grade III, and 1 (1.5%) of grade IV. In 63 spleen injuries scaled by CT the following was present: grade I in 21

  11. Biomechanics and hydrodynamics of prey capture in the Chinese giant salamander reveal a high-performance jaw-powered suction feeding mechanism

    PubMed Central

    Heiss, Egon; Natchev, Nikolay; Gumpenberger, Michaela; Weissenbacher, Anton; Van Wassenbergh, Sam

    2013-01-01

    During the evolutionary transition from fish to tetrapods, a shift from uni- to bidirectional suction feeding systems followed a reduction in the gill apparatus. Such a shift can still be observed during metamorphosis of salamanders, although many adult salamanders retain their aquatic lifestyle and feed by high-performance suction. Unfortunately, little is known about the interplay between jaws and hyobranchial motions to generate bidirectional suction flows. Here, we study the cranial morphology, as well as kinematic and hydrodynamic aspects related to prey capture in the Chinese giant salamander (Andrias davidianus). Compared with fish and previously studied amphibians, A. davidianus uses an alternative suction mechanism that mainly relies on accelerating water by separating the ‘plates’ formed by the long and broad upper and lower jaw surfaces. Computational fluid dynamics simulations, based on three-dimensional morphology and kinematical data from high-speed videos, indicate that the viscerocranial elements mainly serve to accommodate the water that was given a sufficient anterior-to-posterior impulse beforehand by powerful jaw separation. We hypothesize that this modified way of generating suction is primitive for salamanders, and that this behaviour could have played an important role in the evolution of terrestrial life in vertebrates by releasing mechanical constraints on the hyobranchial system. PMID:23466557

  12. 3D Bite Modeling and Feeding Mechanics of the Largest Living Amphibian, the Chinese Giant Salamander Andrias davidianus (Amphibia:Urodela)

    PubMed Central

    Fortuny, Josep; Marcé-Nogué, Jordi; Heiss, Egon; Sanchez, Montserrat; Gil, Lluis; Galobart, Àngel

    2015-01-01

    Biting is an integral feature of the feeding mechanism for aquatic and terrestrial salamanders to capture, fix or immobilize elusive or struggling prey. However, little information is available on how it works and the functional implications of this biting system in amphibians although such approaches might be essential to understand feeding systems performed by early tetrapods. Herein, the skull biomechanics of the Chinese giant salamander, Andrias davidianus is investigated using 3D finite element analysis. The results reveal that the prey contact position is crucial for the structural performance of the skull, which is probably related to the lack of a bony bridge between the posterior end of the maxilla and the anterior quadrato-squamosal region. Giant salamanders perform asymmetrical strikes. These strikes are unusual and specialized behavior but might indeed be beneficial in such sit-and-wait or ambush-predators to capture laterally approaching prey. However, once captured by an asymmetrical strike, large, elusive and struggling prey have to be brought to the anterior jaw region to be subdued by a strong bite. Given their basal position within extant salamanders and their “conservative” morphology, cryptobranchids may be useful models to reconstruct the feeding ecology and biomechanics of different members of early tetrapods and amphibians, with similar osteological and myological constraints. PMID:25853557

  13. Breeding biology of the spotted salamander Ambystoma maculatum (Shaw) in acidic temporary ponds at Cape Cod, USA

    USGS Publications Warehouse

    Portnoy, J.W.

    1990-01-01

    The relationship between water chemistry and breeding success of spotted salamanders Ambystoma maculatum (Shaw) was examined in temporary woodland ponds on outer Cape Cod, Massachusetts in 1985 and 1986. Most pond waters were dilute (3median coductivity = 57 umhos cm-1 (1 umhos cm-1 = 0?1 mSm-1)), acidic (median pH = 4?82), and highly colored (median = 140 Pt-Co units). Most acidity was due to abundant organic acids. Salamander survival to hatching was over 80% at 8 of 12 ponds monitored. Complete mortality, preceded by gross abnormalities, was observed only among embryos in the most acidic spawning pond (pH 4?3-4?5) in both years. Embryo transfers between ponds and laboratory studies indicated that reduced survival was due to the interaction of low pH with high tannin-lignin concentration. The use of amphibian embryonic survival to indicate acid rain effects is complicated by multiple habitat parameters and should only be attempted in conjunction with long-term population monitoring.

  14. Effects of atrazine on egg masses of the yellow-spotted salamander (Ambystoma maculatum) and its endosymbiotic alga (Oophila amblystomatis).

    PubMed

    Baxter, Leilan; Brain, Richard A; Hosmer, Alan J; Nema, Mohini; Müller, Kirsten M; Solomon, Keith R; Hanson, Mark L

    2015-11-01

    Embryonic growth of the yellow-spotted salamander (Ambystoma maculatum) is enhanced by the presence of the green alga Oophila amblystomatis, in the egg capsule. To further assess potential impacts of herbicides on this relationship, A. maculatum egg masses were exposed to atrazine (0-338 μg/L) until hatching (up to 66 days). Exposure to atrazine reduced PSII yield of the symbiotic algae in a concentration-dependent manner, but did not significantly affect visible algal growth or any metrics associated with salamander development. Algal cells were also cultured in the laboratory for toxicity testing. In the 96-h growth inhibition test (0-680 μg/L), ECx values were generally greater than those reported for standard algal test species. Complete recovery of growth rates occurred within 96-h of transferring cells to untreated media. Overall, development of A. maculatum embryos was not affected by exposure to atrazine at concentrations and durations exceeding those found in the environment. PMID:26219074

  15. GLUTAMATE-INDUCED Ca2+ INFLUX IN THIRD-ORDER NEURONS OF SALAMANDER RETINA IS REGULATED BY THE ACTIN CYTOSKELETON

    PubMed Central

    AKOPIAN, A.; SZIKRA, T.; CRISTOFANILLI, M.; KRIZAJ, D.

    2010-01-01

    Ligand-gated ion channels (ionotropic receptors) link to the cortical cytoskeleton via specialized scaffold proteins and thereby to appropriate signal transduction pathways in the cell. We studied the role of filamentous actin in the regulation of Ca influx through glutamate receptor-activated channels in third-order neurons of salamander retina. Staining by Alexa-Fluor 488-phalloidin, to visualize polymerized actin, we show localization of filamentous actin in neurites, and the membrane surrounding the cell soma. With Ca2+ imaging we found that in dissociated neurons, depolymerization of filamentous actin by latrunculin A, or cytochalasin D significantly reduced glutamate-induced intracellular Ca2+ accumulation to 53±7% of control value. Jasplakinolide, a stabilizer of filamentous actin, by itself slightly increased the glutamate-induced Ca2+ signal and completely attenuated the inhibitory effect when applied in combination with actin depolymerizing agents. These results indicate that in salamander retinal neurons the actin cytoskeleton regulates Ca2+ influx through ionotropic glutamate receptor-activated channels, suggesting regulatory roles for filamentous actin in a number of Ca2+-dependent physiological and pathological processes. PMID:16359816

  16. Fine-Scale Habitat Associations of a Terrestrial Salamander: The Role of Environmental Gradients and Implications for Population Dynamics

    PubMed Central

    Peterman, William E.; Semlitsch, Raymond D.

    2013-01-01

    Environmental gradients are instrumental in shaping the distribution and local abundance of species because at the most fundamental level, an organism’s performance is constrained by the environment it inhabits. In topographically complex landscapes, slope, aspect, and vegetative cover interact to affect solar exposure, creating temperature-moisture gradients and unique microclimates. The significance of the interaction of abiotic gradients and biotic factors such as competition, movement, or physiology has long been recognized, but the scale at which these factors vary on the landscape has generally precluded their inclusion in spatial abundance models. We used fine-scale spatial data relating to surface-soil moisture, temperature, and canopy cover to describe the spatial distribution of abundance of a terrestrial salamander, Plethodon albagula, across the landscape. Abundance was greatest in dense-canopy ravine habitats with high moisture and low solar exposure, resulting in a patchy distribution of abundance. We hypothesize that these patterns reflect the physiological constraints of Plethodontid salamanders. Furthermore, demographic cohorts were not uniformly distributed among occupied plots on the landscape. The probability of gravid female occurrence was nearly uniform among occupied plots, but juveniles were much more likely to occur on plots with lower surface temperatures. The disconnect between reproductive effort and recruitment suggests that survival differs across the landscape and that local population dynamics vary spatially. Our study demonstrates a connection between abundance, fine-scale environmental gradients, and population dynamics, providing a foundation for future research concerning movement, population connectivity, and physiology. PMID:23671586

  17. Fine-scale habitat associations of a terrestrial salamander: the role of environmental gradients and implications for population dynamics.

    PubMed

    Peterman, William E; Semlitsch, Raymond D

    2013-01-01

    Environmental gradients are instrumental in shaping the distribution and local abundance of species because at the most fundamental level, an organism's performance is constrained by the environment it inhabits. In topographically complex landscapes, slope, aspect, and vegetative cover interact to affect solar exposure, creating temperature-moisture gradients and unique microclimates. The significance of the interaction of abiotic gradients and biotic factors such as competition, movement, or physiology has long been recognized, but the scale at which these factors vary on the landscape has generally precluded their inclusion in spatial abundance models. We used fine-scale spatial data relating to surface-soil moisture, temperature, and canopy cover to describe the spatial distribution of abundance of a terrestrial salamander, Plethodon albagula, across the landscape. Abundance was greatest in dense-canopy ravine habitats with high moisture and low solar exposure, resulting in a patchy distribution of abundance. We hypothesize that these patterns reflect the physiological constraints of Plethodontid salamanders. Furthermore, demographic cohorts were not uniformly distributed among occupied plots on the landscape. The probability of gravid female occurrence was nearly uniform among occupied plots, but juveniles were much more likely to occur on plots with lower surface temperatures. The disconnect between reproductive effort and recruitment suggests that survival differs across the landscape and that local population dynamics vary spatially. Our study demonstrates a connection between abundance, fine-scale environmental gradients, and population dynamics, providing a foundation for future research concerning movement, population connectivity, and physiology. PMID:23671586

  18. Tongue and taste organ development in the ontogeny of direct-developing salamander Plethodon cinereus (Lissamphibia: Plethodontidae).

    PubMed

    Budzik, Karolina A; Żuwała, Krystyna; Kerney, Ryan

    2016-07-01

    The latest research on direct developing caecilian and anuran species indicate presence of only one generation of taste organs during their ontogeny. This is distinct from indirect developing batrachians studied thus far, which possess taste buds in larvae and anatomically distinct taste discs in metamorphs. This study is a description of the tongue and taste organ morphology and development in direct developing salamander Plethodon cinereus (Plethodontidae) using histology and electron microscopy techniques. The results reveal two distinct stages tongue morphology (primary and secondary), similar to metamorphic urodeles, although only one stage of taste organ morphology. Taste disc sensory zones emerge on the surface of the oropharyngeal epithelium by the end of embryonic development, which coincides with maturation of the soft tongue. Taste organs occur in the epithelium of the tongue pad (where they are situated on the dermal papillae), the palate and the inner surface of the mandible and the maxilla. Plethodon cinereus embryos only possess taste disc type taste organs. Similar to the direct developing anuran Eleutherodactylus coqui (Eleutherodactylidae), these salamanders do not recapitulate larval taste bud morphology as an embryo. The lack of taste bud formation is probably a broadly distributed feature characteristic to direct developing batrachians. J. Morphol. 277:906-915, 2016. © 2016 Wiley Periodicals, Inc. PMID:27087010

  19. Gene lineages and eastern North American palaeodrainage basins: phylogeography and speciation in salamanders of the Eurycea bislineata species complex.

    PubMed

    Kozak, Kenneth H; Blaine, Russell A; Larson, Allan

    2006-01-01

    Contemporary North American drainage basins are composites of formerly isolated drainages, suggesting that fragmentation and fusion of palaeodrainage systems may have been an important factor generating current patterns of genetic and species diversity in stream-associated organisms. Here, we combine traditional molecular-phylogenetic, multiple-regression, nested clade, and molecular-demographic analyses to investigate the relationship between phylogeographic variation and the hydrogeological history of eastern North American drainage basins in semiaquatic plethodontid salamanders of the Eurycea bislineata species complex. Four hundred forty-two sequences representing 1108 aligned bases from the mitochondrial genome are reported for the five formally recognized species of the E. bislineata complex and three outgroup taxa. Within the in-group, 270 haplotypes are recovered from 144 sampling locations. Geographic patterns of mtDNA-haplotype coalescence identify 13 putatively independent population-level lineages, suggesting that the current taxonomy of the group underestimates species-level diversity. Spatial and temporal patterns of phylogeographic divergence are strongly associated with historical rather than modern drainage connections, indicating that shifts in major drainage patterns played a pivotal role in the allopatric fragmentation of populations and build-up of lineage diversity in these stream-associated salamanders. More generally, our molecular genetic results corroborate geological and faunistic evidence suggesting that palaeodrainage connections altered by glacial advances and headwater erosion occurring between the mid-Miocene and Pleistocene epochs explain regional patterns of biodiversity in eastern North American streams. PMID:16367840

  20. Proteomic analysis of the skin from Chinese fire-bellied newt and comparison to Chinese giant salamander.

    PubMed

    Sun, Jingyan; Geng, Xiaofang; Guo, Jianlin; Zang, Xiayan; Li, Pengfei; Li, Deming; Xu, Cunshuan

    2016-09-01

    Animal skin that directly interfaces with the external environment has developed diverse adaptive functions to a variety of ecological conditions laden with pathogenic infection and physical harm. Amphibians exhibit various adaptations related to their "incomplete" shift from the aquatic to the terrestrial habitat. Therefore, it is very necessary to explore the molecular basis of skin function and adaptation in amphibians. Currently, the studies on the molecular mechanisms of skin functions in anuran amphibians have been reported, but in urodele amphibians are rare. This study identified the skin proteomes of Chinese fire-bellied newt Cynops orientalis by a proteomic method, and compared the results to the skin proteomes of Chinese giant salamander Andrias davidianus obtained previously. A total of 452 proteins were identified in the newt skin by MALDI-TOF/MS, and functional annotation results by DAVID analysis showed that special functions such as wound healing, immune response, defense and respiration, were significantly enriched. Comparison results showed that the two species had a great difference in the aspects of protein kinds and abundance, and the highly expressed proteins may tightly correlate with living conditions. Moreover, the newt skin might have stronger immunity, but weaker respiration than the giant salamander skin to adapt to various living environments. This research provides a molecular basis for further studies on amphibian skin function and adaptation. PMID:27343457

  1. A 3D Musculo-Mechanical Model of the Salamander for the Study of Different Gaits and Modes of Locomotion

    PubMed Central

    Harischandra, Nalin; Cabelguen, Jean-Marie; Ekeberg, Örjan

    2010-01-01

    Computer simulation has been used to investigate several aspects of locomotion in salamanders. Here we introduce a three-dimensional forward dynamics mechanical model of a salamander, with physically realistic weight and size parameters. Movements of the four limbs and of the trunk and tail are generated by sets of linearly modeled skeletal muscles. In this study, activation of these muscles were driven by prescribed neural output patterns. The model was successfully used to mimic locomotion on level ground and in water. We compare the walking gait where a wave of activity in the axial muscles travels between the girdles, with the trotting gait in simulations using the musculo-mechanical model. In a separate experiment, the model is used to compare different strategies for turning while stepping; either by bending the trunk or by using side-stepping in the front legs. We found that for turning, the use of side-stepping alone or in combination with trunk bending, was more effective than the use of trunk bending alone. We conclude that the musculo-mechanical model described here together with a proper neural controller is useful for neuro-physiological experiments in silico. PMID:21206530

  2. Tracing the first step to speciation: ecological and genetic differentiation of a salamander population in a small forest.

    PubMed

    Steinfartz, Sebastian; Weitere, Markus; Tautz, Diethard

    2007-11-01

    Mechanisms and processes of ecologically driven adaptive speciation are best studied in natural situations where the splitting process is still occurring, i.e. before complete reproductive isolation is achieved. Here, we present a case of an early stage of adaptive differentiation under sympatric conditions in the fire salamander, Salamandra salamandra, that allows inferring the underlying processes for the split. Larvae of S. salamandra normally mature in small streams until metamorphosis, but in an old, continuous forest area near Bonn (the Kottenforst), we found salamander larvae not only in small streams but also in shallow ponds, which are ecologically very different from small streams. Common-environment experiments with larvae from both habitat types reveal specific adaptations to these different ecological conditions. Mitochondrial and microsatellite analyses show that the two ecologically differentiated groups also show signs of genetic differentiation. A parallel analysis of animals from a neighbouring much larger forest area (the Eifel), in which larvae mature only in streams, shows no signs of genetic differentiation, indicating that gene flow between ecologically similar types can occur over large distances. Hence, geographical factors cannot explain the differential larval habitat adaptations in the Kottenforst, in particular since adult life and mating of S. salamandra is strictly terrestrial and not associated with larval habitats. We propose therefore that the evolution of these adaptations was coupled with the evolution of cues for assortative mating which would be in line with models of sympatric speciation that suggest a co-evolution of habitat adaptations and associated mating signals. PMID:17877714

  3. Thriving in the Cold: Glacial Expansion and Post-Glacial Contraction of a Temperate Terrestrial Salamander (Plethodon serratus)

    PubMed Central

    Newman, Catherine E.; Austin, Christopher C.

    2015-01-01

    The dynamic geologic history of the southeastern United States has played a major role in shaping the geographic distributions of amphibians in the region. In the phylogeographic literature, the predominant pattern of distribution shifts through time of temperate species is one of contraction during glacial maxima and persistence in refugia. However, the diverse biology and ecology of amphibian species suggest that a “one-size-fits-all” model may be inappropriate. Nearly 10% of amphibian species in the region have a current distribution comprised of multiple disjunct, restricted areas that resemble the shape of Pleistocene refugia identified for other temperate taxa in the literature. Here, we apply genetics and spatially explicit climate analyses to test the hypothesis that the disjunct regions of these species ranges are climatic refugia for species that were more broadly distributed during glacial maxima. We use the salamander Plethodon serratus as a model, as its range consists of four disjunct regions in the Southeast. Phylogenetic results show that P. serratus is comprised of multiple genetic lineages, and the four regions are not reciprocally monophyletic. The Appalachian salamanders form a clade sister to all other P. serratus. Niche and paleodistribution modeling results suggest that P. serratus expanded from the Appalachians during the cooler Last Glacial Maximum and has since been restricted to its current disjunct distribution by a warming climate. These data reject the universal applicability of the glacial contraction model to temperate taxa and reiterate the importance of considering the natural history of individual species. PMID:26132077

  4. Life Satisfaction and Morbidity among Postmenopausal Women

    PubMed Central

    Lukkala, Pyry S.; Honkanen, Risto J.; Rauma, Päivi H.; Williams, Lana J.; Quirk, Shae E.; Kröger, Heikki; Koivumaa-Honkanen, Heli

    2016-01-01

    Objective To investigate associations between morbidity and global life satisfaction in postmenopausal women taking into account type and number of diseases. Materials and Methods A total of 11,084 women (age range 57–66 years) from a population-based cohort of Finnish women (OSTPRE Study) responded to a postal enquiry in 1999. Life satisfaction was measured with a 4-item scale. Self-reported diseases diagnosed by a physician and categorized according to ICD-10 main classes were used as a measure of morbidity. Enquiry data on health and lifestyle were used as covariates in the multivariate logistic models. Results Morbidity was strongly associated with life dissatisfaction. Every additional disease increased the risk of life dissatisfaction by 21.1% (p < .001). The risk of dissatisfaction was strongest among women with mental disorders (OR = 5.26; 95%CI 3.84–7.20) and neurological disorders (OR = 3.62; 95%CI 2.60–5.02) compared to the healthy (each p < .001). Smoking, physical inactivity and marital status were also associated with life dissatisfaction (each p < .001) but their introduction to the multivariate model did not attenuate the pattern of associations. Conclusions Morbidity and life dissatisfaction have a disease-specific and dose-dependent relationship. Even if women with mental and neurological disorders have the highest risk for life dissatisfaction, monitoring life satisfaction among aging women regardless of disorders should be undertaken in order to intervene the joint adverse effects of poor health and poor well-being. PMID:26799838

  5. Mortality and cancer morbidity among cement workers.

    PubMed Central

    Jakobsson, K; Horstmann, V; Welinder, H

    1993-01-01

    OBJECTIVE--To explore associations between exposure to cement dust and cause specific mortality and tumour morbidity, especially gastrointestinal tumours. DESIGN--A retrospective cohort study. SUBJECTS AND SETTING--2400 men, employed for at least 12 months in two Swedish cement factories. MAIN OUTCOME MEASURES--Cause specific morality from death certificates (1952-86). Cancer morbidity from tumour registry information (1958-86). Standardised mortality rates (SMRs; national reference rates) and standardised morbidity incidence rates (SIRs; regional reference rates) were calculated. RESULTS--An increased risk of colorectal cancer was found > or = 15 years since the start of employment (SIR 1.6, 95% confidence interval (95% CI) 1.1-2.3), mainly due to an increased risk for tumours in the right part of the colon (SIR 2.7, 95% CI 1.4-4.8), but not in the left part (SIR 1.0, 95% CI 0.3-2.5). There was a numerical increase of rectal cancer (SIR 1.5, 95% CI 0.8-2.5). Exposure (duration of blue collar employment)-response relations were found for right sided colon cancer. After > or = 25 years of cement work, the risk was fourfold (SIR 4.3, 95% CI 1.7-8.9). There was no excess of stomach cancer or respiratory cancer. Neither total mortality nor cause specific mortality were significantly increased. CONCLUSIONS--Diverging risk patterns for tumours with different localisations within the large bowel were found in the morbidity study. Long term exposure to cement dust was a risk factor for right sided colon cancer. The mortality study did not show this risk. PMID:8457494

  6. [Wernicke encephalopathy after subtotal gastrectomy for morbid obesity].

    PubMed

    Gabaudan, C; La-Folie, T; Sagui, E; Soulier, B; Dion, A-M; Richez, P; Brosset, C

    2008-05-01

    Wernicke's encephalopathy (WE) is one of the potential complications of obesity surgery. It is an acute neuropsychiatric syndrome resulting from thiamine deficiency often associated with repeated vomiting. The classic triad is frequently reported in these patients (optic neuropathy, ataxia and confusion), associated with uncommon features. Cerebral impairment affects the dorsal medial nucleus of the thalamus and the periaqueductal grey area, appearing on MRI, as hyperintense signals on T2, Flair and Diffusion weighted imaging. Early diagnosis and parenteral thiamine are required to decrease morbidity and mortality. We report a case of WE and Korsakoff's syndrome in a young obese patient after subtotal gastrectomy, who still has substantial sequelae. The contribution of MRI with diffusion-weighted imaging is illustrated. The interest of nutritional supervision in the first weeks and preventive thiamine supplementation in case of repeated vomiting are of particular importance in these risky situations. PMID:18555879

  7. [Road accidents morbidity and mortality in district of Vrancea].

    PubMed

    Duma, Odetta

    2002-01-01

    Nowadays, road accidents represent an important cause of morbidity and mortality. The present paper is a descriptive study of the most important factors involved in road accidents appearance from the district of Vrancea, in year 2001 and assesses the gravity of premature deaths using potential years of lost life (PYLL). In this district, the level of PYLL due to road accidents in male is significant higher in comparison with female (964 and respectively 408), these data being in concordance with PYLL of the entire country. The most frequent causes involved in road accidents are related to human factor and less to vehicle or road conditions. This category of trauma and deaths may be entirely prevented through educational, law, control or technical measures and using descriptive epidemiological data regarding road traffic. PMID:14974230

  8. Impact of Infection on Stroke Morbidity and Outcomes.

    PubMed

    Miller, Chad M; Behrouz, Réza

    2016-09-01

    Each year, millions of persons worldwide are disabled by stroke. The burden of stroke is expected to increase as a consequence of growth in our elderly population. Outcome is dependent upon limitation of secondary medical processes in the acute setting that lead to deterioration and increased long-term disability. The prevalence of infection after stroke is greater that seen in other medical conditions with similar acuity and its impact upon morbidity and mortality is substantial. Physical impairment and immune modulation are chief determinants in rate of infection after stroke. Each of these factors has been a target for therapeutic intervention. Current best practices for acute stroke management implement strategies for prevention, prompt identification, and treatment of infection. Novel therapies are currently being explored which have the opportunity to greatly minimize infectious complications following stroke. Fever commonly accompanies infection and independently influences stroke outcome. Targeted temperature management provides an additional chance to improve stroke recovery. PMID:27485944

  9. Fluid administration and morbidity in transhiatal esophagectomy

    PubMed Central

    Eng, Oliver S.; Arlow, Renee L.; Moore, Dirk; Chen, Chunxia; Langenfeld, John E.; August, David A.; Carpizo, Darren R.

    2016-01-01

    Background Esophagectomy is associated with significant morbidity. Optimizing perioperative fluid administration is one potential strategy to mitigate morbidity. We sought to investigate the relationship of intraoperative fluid (IOF) administration to outcomes in patients undergoing transhiatal esophagectomy with particular attention to malnourished patients, who may be more susceptible to the effects of fluid overload. Material and methods Patients who underwent transhiatal esophagectomy from 2000–2013 were identified from a retrospective database. IOF rates (mL/kg/hr) were determined and their relationship to outcomes compared. To examine the impact of malnutrition, we stratified patients based on median preoperative serum albumin and compared outcomes. Results and discussion 211 patients comprised the cohort. 74% of patients underwent esophagectomy for esophageal adenocarcinoma. Linear regression analyses were performed comparing independent perioperative variables to four outcomes variables: length of stay, complications per patient, major complications, and Clavien-Dindo classification. IOF rate was significantly associated with three of four outcomes on univariate analysis. Significantly more patients with a preoperative albumin level ≤3.7 g/dL who received more than the median IOF rate experienced more severe complications. Conclusions Increased intraoperative fluid administration is associated with perioperative morbidity in patients undergoing transhiatal esophagectomy. Patients with lower preoperative albumin levels may be particularly sensitive to the effects of volume overload. PMID:26319974

  10. Offspring of diabetic mothers. Problems of morbidity.

    PubMed

    Jährig, D; Stiete, S; Jonas, C

    1993-01-01

    In the past decade, malformation rates and life-threatening neonatal disorders of infants of diabetic mothers have been lowered to a marked degree. However, the remaining neonatal morbidity (metabolic and functional abnormalities and macrosomia) is still rather high. The meaning of these signs and symptoms for the further somatic development is unclear. A study comprising 443 neonatal infants of diabetic mothers was performed in order to quantify the morbidity. In 340 of the mothers, insulin treatment during pregnancy was based on HbA1c and blood glucose values; in the remaining 103 women, it was additionally controlled by measurement of insulin concentration in the amniotic fluid. A new classification of fetopathy at four different stages was established as a basis for further follow-up. In preparation of the latter, a pilot study including 160 infants in their fourth year of life was conducted to test the hypothesis that the further somatic growth is related to neonatal findings. The results demonstrate that the neonatal morbidity profile has changed with therapy. Metabolic control based additionally on insulin concentration in the amniotic fluid has resulted (1) in less infants with macrosomia and/or with striking phenotype but (2) also in a increase of small-for-gestational-age infants and of the frequency of hypoglycaemia. Only purely macrosomatic infants showed a tendency towards obesity and length acceleration in their fourth year of life. PMID:8314428

  11. The Perspectives of Patients on Health-Care for Co-Morbid Diabetes and Chronic Kidney Disease: A Qualitative Study

    PubMed Central

    Lo, Clement; Ilic, Dragan; Teede, Helena; Cass, Alan; Fulcher, Greg; Gallagher, Martin; Johnson, Greg; Kerr, Peter G.; Mathew, Tim; Murphy, Kerry; Polkinghorne, Kevan; Walker, Rowan; Zoungas, Sophia

    2016-01-01

    Background Multi-morbidity due to diabetes and chronic kidney disease (CKD) remains challenging for current health-systems, which focus on single diseases. As a first step toward health-care improvement, we explored the perspectives of patients and their carers on factors influencing the health-care of those with co-morbid diabetes and CKD. Methods In this qualitative study participants with co-morbid diabetes and CKD were purposively recruited using maximal variation sampling from 4 major tertiary health-services from 2 of Australia’s largest cities. Separate focus groups were conducted for patients with CKD stages 3, 4 and 5. Findings were triangulated with semi-structured interviews of carers of patients. Discussions were transcribed verbatim and thematically analysed. Results Twelve focus groups with 58 participants and 8 semi-structured interviews of carers were conducted. Factors influencing health-care of co-morbid diabetes and CKD grouped into patient and health service level factors. Key patient level factors identified were patient self-management, socio-economic situation, and adverse experiences related to co-morbid diabetes and CKD and its treatment. Key health service level factors were prevention and awareness of co-morbid diabetes and CKD, poor continuity and coordination of care, patient and carer empowerment, access and poor recognition of psychological co-morbidity. Health-service level factors varied according to CKD stage with poor continuity and coordination of care and patient and carer empowerment emphasized by participants with CKD stage 4 and 5, and access and poor recognition of psychological co-morbidity emphasised by participants with CKD stage 5 and carers. Conclusions According to patients and their carers the health-care of co-morbid diabetes and CKD may be improved via a preventive, patient-centred health-care model which promotes self-management and that has good access, continuity and coordination of care and identifies and

  12. Contribution of the ciliary cyclic nucleotide-gated conductance to olfactory transduction in the salamander.

    PubMed Central

    Lowe, G; Gold, G H

    1993-01-01

    1. Flash photolysis of caged cyclic nucleotides was used to examine the contribution of the ciliary cyclic nucleotide-gated conductance to olfactory transduction in the tiger salamander. Brief illumination of solitary olfactory receptor cells loaded with 100 microM caged cyclic AMP caused a large inward current (peak amplitude 355 +/- 200 pA; mean +/- S.D. for eleven cells) under whole-cell voltage clamp at -50 mV. 2. The photolysis response was initiated after a latency of 4-12 ms, whereas an odorant response of identical amplitude had a latency of several hundred milliseconds. The amplitudes of both responses exhibited almost identical voltage dependence between -50 and +25 mV, with both reversing near 0 mV. The time courses of the falling phases of odorant and photolysis responses also exhibited similar voltage dependence, both being prolonged at positive voltages. 3. Photolysis of caged cyclic GMP activated a current similar in amplitude and time course to that produced by photolysis of caged cyclic AMP. 4. When the flash was spatially limited to the cilia, the amplitude and duration of the photolysis response increased linearly with the length of the cilia illuminated (for cilia not longer than 30-40 microns) while the latency remained constant at 4-12 ms. The increase in duration was described semi-quantitatively by a model which incorporated diffusion and saturable hydrolysis of cyclic AMP. When the flash was limited to the soma or proximal dendrite, the response latency was proportional to the square of the distance between the illuminated region and the cilia. 5. Dialysis of cells with 500 microM cyclic AMP from a whole-cell electrode under voltage clamp activated a large transient inward current. Simultaneous suction electrode recording showed that this current originated almost entirely from the ciliary membrane. The density of cyclic nucleotide-gated channels was estimated to be 800-fold higher in the cilia than in the soma. 6. Summation of simultaneous

  13. Response properties of cones from the retina of the tiger salamander.

    PubMed Central

    Perry, R J; McNaughton, P A

    1991-01-01

    1. Spectral sensitivity measurements using the suction electrode technique reveal three types of cone in the retina of the tiger salamander, showing maximum sensitivity at wavelengths 610 nm (red-sensitive cone), 444 nm (blue-sensitive cone) and below 400 nm (UV-sensitive cone). 2. The absolute sensitivities of red- and blue-sensitive cones to flashes of optimal wavelength are 0.022 and 0.33 pA photon-1 micron 2 respectively. 3. The time-to-peak of the dim flash response and the recovery of membrane current after a flash of any intensity are fastest in red-sensitive and slowest in blue-sensitive cones. 4. In blue- and UV-sensitive cones the flash response peaks progressively earlier as the flash strength is increased, as in rods. In red-sensitive cones, however, bright flash responses take longer to peak than dim flash responses. 5. In all three cone types, voltage clamping at -40 mV reduces the time-to-peak of the response to a bright flash, showing that the rising phase of the bright flash response is normally limited by the time constant of the cell. Under voltage clamp, all cones show a decrease in time-to-peak with increasing flash intensity. 6. Voltage clamping red-sensitive cones reveals two components of the rising phase of the response to a bright flash. Most of the current is rapidly suppressed by a bright flash, and represents the closure of light-sensitive channels. The residual current decays with a mean time constant of 20 ms, and is probably attributable to the decline of electrogenic Na(+)-Ca2+, K+ exchange. The amplitude of this exchange current suggests that the proportion of the dark current carried by calcium ions is greater in red-sensitive cones than in rods of the same species. 7. In UV-sensitive cones, a prominent oscillation of light-sensitive current is observed during the recovery from flashes of intermediate intensity. A similar, but slower and less prominent oscillation is usually seen in blue-sensitive cones. 8. When a red

  14. A voltage-clamp study of the light response in solitary rods of the tiger salamander.

    PubMed Central

    Bader, C R; Macleish, P R; Schwartz, E A

    1979-01-01

    1. Single, isolated, rod photoreceptors were obtained by enzymatic dissociation of the tiger salamander (Ambystoma tigrinum) retina. These solitary cells retained the morphological features of rods of the intact retina and could be maintained in culture for several days. Solitary cells were penetrated with one or two micropipettes and their electrophysiology was studied by the voltage-clamp technique. 2. Intracellular recording with two micropipettes demonstrated that the inner segment of a solitary rod was effectively isopotential with the outer segment. 3. The time course of the voltage response to a flash resembled that of responses observed in rods in the intact retina. At low light intensities the response reached a peak in approximately 0.7 sec and then slowly declined. At high light intensities the time to peak response decreased and an initial transient arose as the response, after reaching the peak, quickly decreased to a less polarized plateau. 4. The normal voltage response could be compared with the current observed during a voltage clamp. At low light intensities the time course of the current response resembled the time course of the voltage response. When light intensity was increased the time course of the current response differed from the voltage response in that the time to peak amplitude remained relatively constant and an initial transient did not occur. It was possible to predict the current response produced by any intensity of light by using (i) an empirical equation which reproduced the time course of a dim response and (ii) the Michaelis-Menten equation. 5. The time course of the voltage-clamp current produced by a flash was the same at different values of maintained voltage. 6. The maximum amplitude of the voltage-clamp current produced by a flash or step of light was a non-linear function of membrane potential. It was relatively constant within the physiological range, decreased as the membrane potential was moved toward 0 mV, reversed

  15. Light-dependent Changes in Outer Segment Free-Ca2+ Concentration in Salamander Cone Photoreceptors

    PubMed Central

    Sampath, A.P.; Matthews, H.R.; Cornwall, M.C.; Bandarchi, J.; Fain, G.L.

    1999-01-01

    Simultaneous measurements of photocurrent and outer segment Ca2+ were made from isolated salamander cone photoreceptors. While recording the photocurrent from the inner segment, which was drawn into a suction pipette, a laser spot confocal technique was employed to evoke fluorescence from the outer segment of a cone loaded with the Ca2+ indicator fluo-3. When a dark-adapted cone was exposed to the intense illumination of the laser, the circulating current was completely suppressed and fluo-3 fluorescence rapidly declined. In the more numerous red-sensitive cones this light-induced decay in fluo-3 fluorescence was best fitted as the sum of two decaying exponentials with time constants of 43 ± 2.4 and 640 ± 55 ms (mean ± SEM, n = 25) and unequal amplitudes: the faster component was 1.7-fold larger than the slower. In blue-sensitive cones, the decay in fluorescence was slower, with time constants of 140 ± 30 and 1,400 ± 300 ms, and nearly equal amplitudes. Calibration of fluo-3 fluorescence in situ from red-sensitive cones allowed the calculation of the free-Ca2+ concentration, yielding values of 410 ± 37 nM in the dark-adapted outer segment and 5.5 ± 2.4 nM after saturating illumination (mean ± SEM, n = 8). Photopigment bleaching by the laser resulted in a considerable reduction in light sensitivity and a maintained decrease in outer segment Ca2+ concentration. When the photopigment was regenerated by applying exogenous 11-cis-retinal, both the light sensitivity and fluo-3 fluorescence recovered rapidly to near dark-adapted levels. Regeneration of the photopigment allowed repeated measurements of fluo-3 fluorescence to be made from a single red-sensitive cone during adaptation to steady light over a range of intensities. These measurements demonstrated that the outer segment Ca2+ concentration declines in a graded manner during adaptation to background light, varying linearly with the magnitude of the circulating current. PMID:9925824

  16. Electrophysiology of glutamate and sodium co-transport in a glial cell of the salamander retina.

    PubMed Central

    Schwartz, E A; Tachibana, M

    1990-01-01

    1. Müller cells were isolated from salamander retinas and their membrane voltage was controlled with a whole-cell voltage clamp. External D-aspartate, L-aspartate and L-glutamate each induced a membrane current. D-Glutamate, kainate, quisqualate and N-methyl-D-aspartate were more than 100x less effective than L-aspartate. Kynurenic acid had no effect on the current produced by L-glutamate, L-aspartate or D-aspartate. 2. The current induced by an acidic amino acid (AAA) was completely dependent on the presence of external Na+. Neither Li+, Cs+, choline nor TEA+ were able to substitute for Na+. The relationship between external Na+ concentration and current amplitude can be explained if the binding of three Na+ ions enabled transport. The apparent affinity constant for Na+ binding was 41 mM. Altering K+, H+ and Cl- concentrations demonstrated that these ions are not required for transport. 3. The shape of the current-voltage relation did not depend on the external amino acid concentration. The relationship between D-aspartate concentration and current amplitude can be described by the binding of D-aspartate to a single site with an apparent affinity constant of 20 microM. 4. Influx and efflux of AAA were not symmetric. Although influx was electrogenic, efflux did not produce a current. Moreover, influx stimulated efflux; but efflux inhibited influx. 5. Removing external Na+ demonstrated that Na+ carried a current in the absence of an AAA. Li+ was a very poor substitute for Na+. This current may be due to the uncoupled movement of Na+ through the transporter. The relationship between the external Na+ concentration and the amplitude of the uncoupled current can be explained if the binding of two or three Na+ ions enabled the translocation of Na+ in the absence of an AAA. The apparent affinity constant for Na+ binding was approximately 90 mM. 6. The temperature dependence of the AAA-induced current had a Q10 between 8 and 18 degrees C of 1.95. The Q10 is consistent

  17. The effect of light on outer segment calcium in salamander rods

    PubMed Central

    Matthews, Hugh R; Fain, Gordon L

    2003-01-01

    Calcium acts as a second messenger in vertebrate rods, regulating the recovery phase of the light response and modulating sensitivity during light-adaptation. Since light not only decreases the outer segment calcium concentration ([Ca2+]i) by closing cyclic nucleotide-gated channels but can also increase [Ca2+]i by releasing Ca2+ from buffer sites or intracellular stores, we examined in detail the effect of light and circulating current on [Ca2+]i by making simultaneous measurements of suction pipette current and [Ca2+]i from isolated rods of the salamander Ambystoma tigrinum after incorporation of the fluorescent dye fluo-5F. When the release of Ca2+ is measured in 0 Ca2+−0 Na+ solution, minimising fluxes of Ca2+ across the plasma membrane, it is substantial only for light bright enough to bleach a significant fraction of the photopigment and is restricted to the part of the outer segment in which the bleach occurred. It is unlikely, therefore, to make a large contribution to [Ca2+]i for most of the physiological operating range of the rod. Nevertheless, since release is half-maximal for a bleach of less than 10 %, it cannot be produced by a simple mechanism such as a change in the affinity of a binding site on rhodopsin itself but must instead require some more complex interaction. In Ringer solution, the Ca2+ in the light-releasable pool can be discharged merely by the decrease in [Ca2+]i that occurs as the outer segment channels close. In steady background light or after exposure to saturating illumination, the fraction of Ca2+ in the pool decreases essentially in proportion to [Ca2+]i as if Ca2+ were being removed from a buffer site within the cytoplasm. Furthermore, [Ca2+]i itself changes in proportion to the circulating current, with little evidence for a contribution from Ca2+ release or other mechanisms of Ca2+ homeostasis. This indicates that flux of Ca2+ across the plasma membrane is the major determinant of outer segment Ca2+ concentration within the

  18. A light-dependent increase in free Ca2+ concentration in the salamander rod outer segment

    PubMed Central

    Matthews, Hugh R; Fain, Gordon L

    2001-01-01

    The Ca2+ indicator dye fluo-5F was excited by an argon ion laser to measure changes in free Ca2+ concentration ([Ca2+]i) in the outer segments of isolated salamander rods rapidly exposed to a 0 Ca2+, 0 Na+ solution designed to minimise surface membrane Ca2+ fluxes. Over 30-60 s of laser illumination, the fluorescence first increased rapidly and then declined at a rate that was much slower than in Ringer solution and consistent with previous physiological evidence that 0 Ca2+, 0 Na+ solution greatly retards light-induced changes in [Ca2+]i. The initial increase in fluorescence was investigated with a sequence of 100 ms laser flashes presented at 5 s intervals. The fluorescence evoked by the second laser flash was on average 30 % larger than the first, and subsequent responses exhibited a slow decline like that measured with continuous laser exposures. The initial increase in fluorescence did not depend upon the timing of exposure to 0 Ca2+, 0 Na+ solution but appeared to be evoked by exposure to the laser light. Both the increase and subsequent decline in fluorescence measured with brief laser flashes could be reduced by incorporation of the Ca2+ chelator BAPTA. This and other results indicate that the fluorescence increase was unlikely to have been caused by a change in the affinity of fluo-5F for Ca2+ or an increase in the quantity of incorporated dye available to bind Ca2+ but reflects an actual release of intracellular Ca2+ within the outer segment. The pool of Ca2+ available to be released could be decreased if, before the first laser flash, the rod was exposed to light bright enough to bleach a substantial fraction of the photopigment. The releasable pool could also be depleted by exposure to saturating light of much lower intensity if delivered in Ringer solution but not if delivered in 0 Ca2+, 0 Na+ solution. We conclude that Ca2+ can be released within the outer segment both by the bleaching of rhodopsin and by the reduction in [Ca2+]i which normally

  19. Kinetics of Recovery of the Dark-adapted Salamander Rod Photoresponse

    PubMed Central

    Nikonov, S.; Engheta, N.; Pugh, E.N.

    1998-01-01

    The kinetics of the dark-adapted salamander rod photocurrent response to flashes producing from 10 to 105 photoisomerizations (Φ) were investigated in normal Ringer's solution, and in a choline solution that clamps calcium near its resting level. For saturating intensities ranging from ∼102 to 104 Φ, the recovery phases of the responses in choline were nearly invariant in form. Responses in Ringer's were similarly invariant for saturating intensities from ∼103 to 104 Φ. In both solutions, recoveries to flashes in these intensity ranges translated on the time axis a constant amount (τc) per e-fold increment in flash intensity, and exhibited exponentially decaying “tail phases” with time constant τc. The difference in recovery half-times for responses in choline and Ringer's to the same saturating flash was 5–7 s. Above ∼104 Φ, recoveries in both solutions were systematically slower, and translation invariance broke down. Theoretical analysis of the translation-invariant responses established that τc must represent the time constant of inactivation of the disc-associated cascade intermediate (R*, G*, or PDE*) having the longest lifetime, and that the cGMP hydrolysis and cGMP-channel activation reactions are such as to conserve this time constant. Theoretical analysis also demonstrated that the 5–7-s shift in recovery half-times between responses in Ringer's and in choline is largely (4–6 s) accounted for by the calcium-dependent activation of guanylyl cyclase, with the residual (1–2 s) likely caused by an effect of calcium on an intermediate with a nondominant time constant. Analytical expressions for the dim-flash response in calcium clamp and Ringer's are derived, and it is shown that the difference in the responses under the two conditions can be accounted for quantitatively by cyclase activation. Application of these expressions yields an estimate of the calcium buffering capacity of the rod at rest of ∼20, much lower than previous

  20. [The characteristics of morbidity of workers of nuclear power engineering enterprise].

    PubMed

    Pischugina, A V; Ivanov, A G; Belyakova, N A

    2013-01-01

    The article considers the morbidity endocrine, pathology included, of workers of nuclear power station and body-abled population of the district employed in other areas of professional activities. The statistically reliable exceeding of the level of primarily diagnosed endocrine morbidity in the group of working population of the district as compared with the group of workers of nuclear power station is established. In the compared groups, the structure of pathology of endocrine system is characterized by the prevalence of diseases of thyroid gland and obesity. The official statistics data reflects the level of morbidity of working population depending on appealability to curative preventive institutions, ratio and scope of the periodic medical examinations, availability of shop therapeutic service and possibility to involve physicians-specialists to health posts enterprises. Therefore, the foundation of enhancement of quality of medical care to workers is the improvemnent of organizational activities at the level of primary health care. PMID:23672064

  1. Next steps to reduce maternal morbidity and mortality in the USA.

    PubMed

    Kilpatrick, Sarah J

    2015-03-01

    Maternal mortality is rising in the USA. The pregnancy-related maternal mortality ratio increased from 10/100,000 to 17/100,000 live births from the 1990s to 2012. A large proportion of maternal deaths are preventable. This review highlights a national approach to reduce maternal death and morbidity and discusses multiple efforts to reduce maternal morbidity, death and improve obstetric safety. These efforts include communication and collaboration between all stake holders involved in perinatal health, creation of national bundles addressing key maternal care areas such as hemorrhage management, call for all obstetric hospitals to review and analyze all cases of severe maternal morbidity, and access to contraception. Implementation of interventions based on these efforts is a national imperative to improve obstetric safety. PMID:25776293

  2. Prevalence and Patterns of Multi-Morbidity in Serbian Adults: A Cross-Sectional Study

    PubMed Central

    Jovic, Dragana; Vukovic, Dejana; Marinkovic, Jelena

    2016-01-01

    Introduction Like many developing countries, Serbia is facing a growing burden of chronic diseases. Within such public health issue, multi-morbidity requires a special attention. Aims This study investigated the prevalence of multi-morbidity in the Serbia population and assessed the co-occurrence of chronic diseases by age and gender. Methods We analyzed data from the 2013 National Health Survey, which included 13,103 individuals ≥ 20 years old. Multi-morbidity patterns were identified by exploratory factor analysis of data on self-reported chronic diseases, as well as data on measured body weight and height. The analysis was stratified by age and gender. Results Multi-morbidity was present in nearly one-third of respondents (26.9%) and existed in all age groups, with the highest prevalence among individuals aged 65 years and older (47.2% of men and 65.0% of women). Six patterns of multi-morbidity were identified: non-communicable, cardio-metabolic, respiratory, cardiovascular, aggregate, and mechanical/mental/metabolic. The non-communicable pattern was observed in both genders but only in the 20–44 years age group, while the aggregate pattern occurred only in middle-aged men. Cardio-metabolic and respiratory patterns were present in all age groups. Cardiovascular and mechanical/mental/metabolic patterns showed similar presentation in both men and women. Conclusions Multi-morbidity is a common occurrence among adults in Serbia, especially in the elderly. While several patterns may be explained by underlying pathophysiologies, some require further investigation and follow-up. Recognizing the complexity of multi-morbidity in Serbia is of great importance from both clinical and preventive perspectives given that it affects one-third of the population and may require adjustment of the healthcare system to address the needs of affected individuals. PMID:26871936

  3. MORBIDITY PATTERNS AMONG KING FAISAL UNIVERSITY STUDENTS, AL HASSA, KINGDOM OF SAUDI ARABIA

    PubMed Central

    Choudary, Abdulrashid C.; Al-Sultan, Ali I.; Tawfik, Tarek T.

    2007-01-01

    Objectives: To explore the prevalent morbidity problems among students at King Faisal University. To identify the nature of referred cases and assess the efficiency of the referral system. Subjects and Methods: This was a retrospective, records-based descriptive study, involving the examination of the health records of students at King Faisal University, who attended the Medical Center for Primary Health Care services in a five-year period. A pre-tested compilation sheet was used for data collection. Results: Out of 2472 consultations, about 58 % of the diagnosed morbidity conditions were of infectious nature, mostly affecting the respiratory (62%), dental (14%), gastrointestinal (7%), and skin infections (5 %), with more prevalence among males. The non-infectious morbidity conditions were recorded more among females and included muscle and joints problems (16 %), allergic conditions (15 %), gastrointestinal (8 %), and trauma (5 %). Some of the encountered morbidity demonstrated seasonal variation. Case referrals were about 6 %, more in the non-infectious conditions, with a deficient feedback system. Conclusion: Quality improvement of the medical records and the establishment of a proper referral system are necessary. Health education on preventable morbid conditions should be organized and implemented. PMID:23012142

  4. Perioperative morbidity of radical cystectomy: A review

    PubMed Central

    Kulkarni, Jagdeesh N.

    2011-01-01

    A systematic review of the literature on perioperative morbidity (POM) was done using Medline software with a combination of keywords like mortality, morbidity, and complications. In addition, we review the analysis of our hospital data of 261 Radical cystectomies (RCs) performed in an 11-year period and our latest clinical pathway for RC. Age range in our series was 50 to 81 years with 240 males and 21 females. RCs were performed by intraperitoneal method in 172 patients and by our extraperitoneal (EP) method in 89 patients. Urinary diversion was ileal conduit in 159 patients and neobladder in 102 patients. Blood loss ranged between 500 and 1500 ccs. Postoperative mortality occurred in eight patients (3%). Among the other early post-op complications, major urinary leak was seen in nine and minor in 11, requiring PCN in five patients and reoperation in four patients. Bowel leak or obstruction was seen in six and four patients, respectively, requiring reoperation in six patients. EP RC in our series showed some benefit in reduction of POM. The mortality of RC has declined but the POM still ranges from 11 to 68%, as reported in 23 series (1999-2008) comprising of 14 076 patients. Various risk factors leading to POM and some corrective measures are discussed in detail. However, most of these series are retrospective and lack standard complication reporting, which limits the comparison of outcomes. Various modifications in open surgical technique and laparoscopic and Robotic approaches are aimed at reduction in mortality and POM of RC. PMID:21814314

  5. Vivax Malaria: A Major Cause of Morbidity in Early Infancy

    PubMed Central

    Poespoprodjo, Jeanne R.; Fobia, Wendelina; Kenangalem, Enny; Lampah, Daniel A.; Hasanuddin, Afdal; Warikar, Noah; Sugiarto, Paulus; Tjitra, Emiliana; Anstey, Nick M.; Price, Ric N.

    2015-01-01

    Background In areas where malaria is endemic, infants aged <3 months appear to be relatively protected from symptomatic and severe Plasmodium falciparum malaria, but less is known about the effect of Plasmodium vivax infection in this age group. Methods To define malaria morbidity in the first year of life in an area where both multidrug-resistant P. falciparum and P. vivax are highly prevalent, data were gathered on all infants attending a referral hospital in Papua, Indonesia, using systematic data forms and hospital computerized records. Additional clinical and laboratory data were prospectively collected from inpatients aged <3 months. Results From April 2004 through April 2008, 4976 infants were admitted to the hospital, of whom 1560 (31%) had malaria, with infection equally attributable to P. falciparum and P. vivax. The case-fatality rate was similar for inpatients with P. falciparum malaria (13 [2.2%] of 599 inpatients died) and P. vivax malaria (6 [1.0%] of 603 died; P = .161), whereas severe malarial anemia was more prevalent among those with P. vivax malaria (193 [32%] of 605 vs. 144 [24%] of 601; P = .025). Of the 187 infants aged <3 months, 102 (56%) had P. vivax malaria, and 55 (30%) had P. falciparum malaria. In these young infants, infection with P. vivax was associated with a greater risk of severe anemia (odds ratio, 2.4; 95% confidence interval, 1.03–5.91; P = .041) and severe thrombocytopenia (odds ratio, 3.3; 95% confidence interval, 1.07–10.6; P = .036) compared with those who have P. falciparum infection. Conclusions P. vivax malaria is a major cause of morbidity in early infancy. Preventive strategies, early diagnosis, and prompt treatment should be initiated in the perinatal period. PMID:19438395

  6. Hatching success in salamanders and chorus frogs at two sites in Colorado, USA: Effects of acidic deposition and climate

    USGS Publications Warehouse

    Muths, E.; Campbell, D.H.; Corn, P.S.

    2003-01-01

    The snowpack in the vicinity of the Mount Zirkel Wilderness Area is among the most acidic in the western United States. We analyzed water chemistry and examined hatching success in tiger salamanders and chorus frogs at ponds there and at nearby Rabbit Ears Pass (Dumont) to determine whether acid deposition affects amphibians or their breeding habitats at these potentially sensitive locations. We found a wide range of acid neutralizing capacity among ponds within sites; the minimum pH recorded during the experiment was 5.4 at one of 12 ponds with all others at pH ??? 5.7. At Dumont, hatching success for chorus frogs was greater in ponds with low acid neutralizing capacity; however, lowest pHs were >5.8. At current levels of acid deposition, weather and pond characteristics are likely more important than acidity in influencing hatching success in amphibian larvae at these sites.

  7. Development of the Roll-Induced Vestibuloocular Reflex in the Absence of Vestibular Experience in Salamander Tadpoles (Pleurodeles Waltl)

    NASA Astrophysics Data System (ADS)

    Horn, Eberhard R.; Gabriel, Martin; Frippiat, Jean-Pol

    2008-06-01

    The macula organ of the labyrinth is stimulated by body roll or translatory movements. Due to its slow development, the salamander Pleurodeles waltl is an excellent model to study the impact of microgravity on the development of the roll-induced vestibuloocular reflex (rVOR) in the absence of any macular stimulation. The experiment was performed during the Soyuz mission TMA8 (return flight TMA7) in 2006 as part of the experiment AMPHIBODY. It was supplemented by a 3g-hypergravity experiment. It was shown, that microgravity retards the over-all development of Pleurodeles tadpoles but not specifically functional development of the vestibular system; normalization took place within 3 to 4 weeks after landing. Hypergravity accelerated rVOR development in the long-term frame.

  8. Self Report Co-Morbidity and Health Related Quality of Life -- A Comparison with Record Based Co-Morbidity Measures

    ERIC Educational Resources Information Center

    Voaklander, Donald C.; Kelly, Karen D.; Jones, C. Allyson; Suarez-Almazor, Maria E.

    2004-01-01

    The purpose of this project was to compare three hospital-based measures of co-morbidity to patient self-report co-morbidity and to determine the relative proportion of outcome predicted by each of the co-morbidity measures in a population of individuals receiving major joint arthroplasty. Baseline measures using the SF-36 general health…

  9. Hindcasting Historical Breeding Conditions for an Endangered Salamander in Ephemeral Wetlands of the Southeastern USA: Implications of Climate Change.

    PubMed

    Chandler, Houston C; Rypel, Andrew L; Jiao, Yan; Haas, Carola A; Gorman, Thomas A

    2016-01-01

    The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders (Ambystoma bishopi), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A. bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006-2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896-2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A. bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A. bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions. PMID:26910245

  10. Hindcasting Historical Breeding Conditions for an Endangered Salamander in Ephemeral Wetlands of the Southeastern USA: Implications of Climate Change

    PubMed Central

    Chandler, Houston C.; Rypel, Andrew L.; Jiao, Yan; Haas, Carola A.; Gorman, Thomas A.

    2016-01-01

    The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders (Ambystoma bishopi), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A. bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006–2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896–2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A. bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A. bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions. PMID:26910245

  11. The importance of comparative phylogeography in diagnosing introduced species: a lesson from the seal salamander, Desmognathus monticola

    PubMed Central

    Bonett, Ronald M; Kozak, Kenneth H; Vieites, David R; Bare, Alison; Wooten, Jessica A; Trauth, Stanley E

    2007-01-01

    Background In most regions of the world human influences on the distribution of flora and fauna predate complete biotic surveys. In some cases this challenges our ability to discriminate native from introduced species. This distinction is particularly critical for isolated populations, because relicts of native species may need to be conserved, whereas introduced species may require immediate eradication. Recently an isolated population of seal salamanders, Desmognathus monticola, was discovered on the Ozark Plateau, ~700 km west of its broad continuous distribution in the Appalachian Mountains of eastern North America. Using Nested Clade Analysis (NCA) we test whether the Ozark isolate results from population fragmentation (a natural relict) or long distance dispersal (a human-mediated introduction). Results Despite its broad distribution in the Appalachian Mountains, the primary haplotype diversity of D. monticola is restricted to less than 2.5% of the distribution in the extreme southern Appalachians, where genetic diversity is high for other co-distributed species. By intensively sampling this genetically diverse region we located haplotypes identical to the Ozark isolate. Nested Clade Analysis supports the hypothesis that the Ozark population was introduced, but it was necessary to include haplotypes that are less than or equal to 0.733% divergent from the Ozark population in order to arrive at this conclusion. These critical haplotypes only occur in < 1.2% of the native distribution and NCA excluding them suggest that the Ozark population is a natural relict. Conclusion Our analyses suggest that the isolated population of D. monticola from the Ozarks is not native to the region and may need to be extirpated rather than conserved, particularly because of its potential negative impacts on endemic Ozark stream salamander communities. Diagnosing a species as introduced may require locating nearly identical haplotypes in the known native distribution, which may be

  12. Molecular detection of vertebrates in stream water: A demonstration using rocky mountain tailed frogs and Idaho giant salamanders

    USGS Publications Warehouse

    Goldberg, C.S.; Pilliod, D.S.; Arkle, R.S.; Waits, L.P.

    2011-01-01

    Stream ecosystems harbor many secretive and imperiled species, and studies of vertebrates in these systems face the challenges of relatively low detection rates and high costs. Environmental DNA (eDNA) has recently been confirmed as a sensitive and efficient tool for documenting aquatic vertebrates in wetlands and in a large river and canal system. However, it was unclear whether this tool could be used to detect low-density vertebrates in fast-moving streams where shed cells may travel rapidly away from their source. To evaluate the potential utility of eDNA techniques in stream systems, we designed targeted primers to amplify a short, species-specific DNA fragment for two secretive stream amphibian species in the northwestern region of the United States (Rocky Mountain tailed frogs, Ascaphus montanus, and Idaho giant salamanders, Dicamptodon aterrimus). We tested three DNA extraction and five PCR protocols to determine whether we could detect eDNA of these species in filtered water samples from five streams with varying densities of these species in central Idaho, USA. We successfully amplified and sequenced the targeted DNA regions for both species from stream water filter samples. We detected Idaho giant salamanders in all samples and Rocky Mountain tailed frogs in four of five streams and found some indication that these species are more difficult to detect using eDNA in early spring than in early fall. While the sensitivity of this method across taxa remains to be determined, the use of eDNA could revolutionize surveys for rare and invasive stream species. With this study, the utility of eDNA techniques for detecting aquatic vertebrates has been demonstrated across the majority of freshwater systems, setting the stage for an innovative transformation in approaches for aquatic research.

  13. Adenosine inhibits voltage-dependent Ca2+ influx in cone photoreceptor terminals of the tiger salamander retina.

    PubMed

    Stella, Salvatore L; Hu, Wanda D; Vila, Alejandro; Brecha, Nicholas C

    2007-04-01

    Endogenous adenosine has already been shown to inhibit transmitter release from the rod synapse by suppressing Ca(2+) influx through voltage-gated Ca(2+) channels. However, it is not clear how adenosine modulates the cone synapse. Cone photoreceptors, like rod photoreceptors, also possess L-type Ca(2+) channels that regulate the release of L-glutamate. To assess the impact of adenosine on Ca(2+) influx though voltage-gated Ca(2+) channels in cone terminals, whole-cell perforated-patch clamp recording and Ca(2+) imaging with fluo-4 were used on isolated cones and salamander retinal slices. Synaptic markers (VAMP and piccolo) and activity-dependent dye labeling revealed that tiger salamander cone terminals contain a broad, vesicle-filled cytoplasmic extension at the base of the somatic compartment, which is unlike rod terminals that contain one or more thin axons, each terminating in a large bulbous synaptic terminal. The spatiotemporal Ca(2+) responses of the cone terminals do not differ significantly from the Ca(2+) responses of the soma or inner segment like that observed in rods. Whole-cell recording of cone I(Ca) and Ca(2+) imaging of synaptic terminals in cones demonstrate that adenosine inhibited both I(Ca) and the depolarization-evoked Ca(2+) increase in cone terminals in a dose-dependent manner from 1 to 50 muM. These results indicate that, as in rods, adenosine's ability to suppress voltage-dependent Ca(2+) channels at the cone synapse will limit the amount of L-glutamate released. Therefore, adenosine has an inhibitory effect on L-glutamate release at the first synapse, which likely favors elevated adenosine levels in the dark or during dark-adapted conditions. PMID:17304584

  14. Childhood maltreatment and violence: mediation through psychiatric morbidity.

    PubMed

    González, Rafael A; Kallis, Constantinos; Ullrich, Simone; Barnicot, Kirsten; Keers, Robert; Coid, Jeremy W

    2016-02-01

    Childhood maltreatment is associated with multiple adverse outcomes in adulthood including poor mental health and violence. We investigated direct and indirect pathways from childhood maltreatment to adult violence perpetration and the explanatory role of psychiatric morbidity. Analyses were based on a population survey of 2,928 young men 21-34 years in Great Britain in 2011, with boost surveys of black and minority ethnic groups and lower social grades. Respondents completed questionnaires measuring psychiatric diagnoses using standardized screening instruments, including antisocial personality disorder (ASPD), drug and alcohol dependence and psychosis. Maltreatment exposures included childhood physical abuse, neglect, witnessing domestic violence and being bullied. Adult violence outcomes included: any violence, violence toward strangers and intimate partners (IPV), victim injury and minor violence. Witnessing domestic violence showed the strongest risk for adult violence (AOR 2.70, 95% CI 2.00, 3.65) through a direct pathway, with psychotic symptoms and ASPD as partial mediators. Childhood physical abuse was associated with IPV (AOR 2.33, 95% CI 1.25, 4.35), mediated by ASPD and alcohol dependence. Neglect was associated with violence toward strangers (AOR 1.73, 95% CI 1.03, 2.91), mediated by ASPD. Prevention of violence in adulthood following childhood physical abuse and neglect requires treatment interventions for associated alcohol dependence, psychosis, and ASPD. However, witnessing family violence in childhood had strongest and direct effects on the pathway to adult violence, with important implications for primary prevention. In this context, prevention strategies should prioritize and focus on early childhood exposure to violence in the family home. PMID:26803688

  15. Morbidity in whooping cough and measles.

    PubMed Central

    Conway, S P; Phillips, R R

    1989-01-01

    Parents of 99 children who were admitted to hospital with whooping cough or measles, and of 50 children with whooping cough or measles who were nursed at home, were interviewed to determine the extent of morbidity and its effects on the family. Children admitted with whooping cough or measles spent a mean of 12.6 and 5.8 days in hospital, respectively. Time to full recovery was 13.7 and 2.1 weeks, respectively. Over a third of the children who were admitted were emotionally upset during the admission and for several weeks afterwards. Parental anxiety and exhaustion were common. Routine family life was appreciably disturbed. Advice from health care professionals, based on misconceptions of valid contradictions to immunisation, was the main reason for refusing vaccination. PMID:2817928

  16. Respiratory Morbidity in Late Preterm Births

    PubMed Central

    Hibbard, Judith U; Wilkins, Isabelle; Sun, Liping; Gregory, Kimberly; Haberman, Shoshana; Hoffman, Matthew; Kominiarek, Michelle A.; Reddy, Uma; Bailit, Jennifer; Branch, D. Ware; Burkman, Ronald; Gonzalez Quintero, Victor Hugo; Hatjis, Christos G.; Landy, Helain; Ramirez, Mildred; VanVeldhuisen, Paul; Troendle, James; Zhang, Jun

    2014-01-01

    Context Late preterm births (LPTB, 34 0/7-36 6/7 weeks) account for a growing proportion of prematurity-associated short term morbidities, particularly respiratory, that require specialized care and prolonged neonatal hospital stays. Objective To assess short-term respiratory morbidity in LPTB compared to term births in a contemporary cohort of deliveries in the United States. Design, Setting, and Participants Retrospective collection of electronic data from 12 institutions (19 hospitals) across the United States on 233,844 deliveries between 2002 and 2008. Charts were abstracted for all neonates with respiratory compromise admitted to a neonatal intensive care unit (NICU) and LPTB were compared to term births in regard to resuscitation, respiratory support and respiratory diagnoses. A multivariate logistic regression analysis compared infants at each gestational week controlling for factors that influence respiratory outcomes. Main outcome measures Respiratory distress syndrome (RDS), transient tachypnea of the newborn (TTN), pneumonia, respiratory failure, standard and oscillatory ventilator support. Results Of 19,334 LPTB, 7,055 were admitted to a NICU and 2,032 had respiratory compromise. Of 165,993 term infants, 11,980 were admitted to a NICU, 1,874 with respiratory morbidity. Respiratory distress syndrome decreased from 10.5% (390/3700) at 34 weeks to 0.3% (140/41,764) at 38 weeks. Similarly, TTN decreased from 6.4% (n=236) to 0.4% (n=155), pneumonia from 1.5% (n=55) to 0.1% (n=62), and respiratory failure from 1.6% (n=61) to 0.2% (n=63). Standard and oscillatory ventilator support had similar patterns. Odds of RDS decreased with each advancing week until 38 weeks compared to 39-40 weeks (adjusted OR at 34 weeks 40.1 [95% CI 32.0-50.3] and at 38 weeks 1.1 [95% CI, 0.9-1.4]). At 37 weeks odds for RDS were greater than 39-40 weeks (3.1 [95% CI, 2.5-3.7]), but the odds at 38 weeks did not differ from 39-40 weeks. Similar patterns were noted for TTN (adjusted OR

  17. Termination of pregnancy and psychiatric morbidity.

    PubMed

    Gilchrist, A C; Hannaford, P C; Frank, P; Kay, C R

    1995-08-01

    Between October 1976 and July 1979, 1509 general practitioners throughout the UK recruited 13,261 women with an unplanned pregnancy to a prospective study comparing the subsequent psychiatric morbidity rate in the women who underwent an induced abortion with that of the women with other pregnancy outcomes. There was no significant difference in the rates of total psychiatric disorder between women who underwent pregnancy termination and those who underwent childbirth. For example, among women who had no previous illness, the standardized rate of any psychiatric illness was 63.5/1000 woman-years for women who underwent abortion compared to 60.8-63.1/1000 woman-years for other women. In fact, the relative risk (RR) for every group was 1. Women with no history of psychosis faced a lower risk of psychosis after abortion than women with an unplanned pregnancy but who did not seek abortion (4.9/1000 woman-years vs. 11.8/1000 woman-years; RR = 0.4). On the other hand, the rates of psychosis requiring hospital admission for the two groups were similar. In women with no earlier history of psychiatric illness, deliberate self-harm (DSH) occurred significantly more often in women who underwent induced abortion (RR = 1.7) or who were refused an abortion (RR = 2.9). Drug overdoses comprised 89% of DSH cases. DSH was associated with a past history of DSH. It had an inverse trend with age. Women with no history of psychiatric illness had a significant increased risk of subsequent DSH whether they underwent abortion (RR = 1.7) or were refused abortion (RR= 2.9). These findings indicate that psychiatric morbidity after induced abortion is similar to that after childbirth. PMID:7582677

  18. Calcium homeostasis in the outer segments of retinal rods from the tiger salamander.

    PubMed Central

    Lagnado, L; Cervetto, L; McNaughton, P A

    1992-01-01

    1. The processes regulating intracellular calcium in the outer segments of salamander rods have been investigated. The main preparation used was the isolated rod loaded with the Ca(2+)-sensitive photoprotein aequorin, from which outer segment membrane current and free [Ca2+]i could be recorded simultaneously. Two other preparations were also used: outer segment membrane current was recorded from intact, isolated rods using a suction pipette, and from detached outer segments using a whole-cell pipette. 2. Measurements of free intracellular [Ca2+] in Ringer solution were obtained from two aequorin-loaded rods. Mean [Ca2+]i in darkness was 0.41 microM, and after a bright flash [Ca2+]i fell to below detectable levels ( < 0.3 microM). No release of intracellular Ca2+ by a bright flash of light could be detected ( < 0.2 microM). 3. Application of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) caused an increase in the size of the light-sensitive current and a rise in [Ca2+]i, but application of IBMX either when the light-sensitive channels had been closed by a bright light or in the absence of external Ca2+ caused no detectable rise in [Ca2+]i. It is concluded that IBMX increases [Ca2+]i by opening light-sensitive channels, and does not release Ca2+ from stores within the outer segment. 4. Removal of external Na+ caused a rise in [Ca2+]i to around 2 microM and completely suppressed the light-sensitive current. 5. The Na(+)-Ca2+, K+ exchange current in aequorin-loaded rods was activated in first-order manner by internal free calcium, with a mean Michaelis constant, KCa, of 1.6 microM. 6. The KCa of the Na(+)-Ca2+, K+ exchange was increased by elevating internal [Na+]. 7. The Michaelis relation between [Ca2+]i and the activity of the Na(+)-Ca2+, K+ exchange was used to calculate the change in [Ca2+]i occurring during the response to a bright light. In aequorin-loaded rods in Ringer solution the mean change in free [Ca2+]i after a bright flash was 0

  19. Time course and magnitude of the calcium release induced by bright light in salamander rods

    PubMed Central

    Matthews, Hugh R; Fain, Gordon L

    2002-01-01

    Changes in fluorescence were measured with an argon ion laser from the outer segments of isolated salamander rods containing the Ca2+-sensitive fluorescent dye fluo-5F. When the outer segments were exposed to a 0Ca2+/0Na+ solution designed to minimise surface membrane Ca2+ fluxes, exposure to intense light from the laser evoked a slow increase in fluorescence, reflecting a light-induced rise in outer segment [Ca2+]i. The time course of this slow fluorescence rise could be fitted with the sum of two asymptotic exponential functions of approximately equal amplitude, having time constants of approximately 200 ms and 5.7 s. When rods were exposed to saturating background light to reduce outer segment [Ca2+]i before laser illumination, the relative amplitude of the two exponentials was altered so as to reduce the contribution from the one with the shorter time constant. Examination of the initial time course of fluorescence when recording at high temporal resolution revealed a further rapid rise with a time constant of 1–2 ms, which could be observed even from rods in Ringer solution. This initial rapid rise could be abolished by pre-exposing the rod to bleaching illumination, whether the bleach was given in Ringer solution or in 0Ca2+/0Na+ solution. It would therefore appear that the rapid rise in fluorescence is generated in some way by the bleaching of the photopigment. Unlike the slower components of fluorescence increase, the rapid initial rise was virtually unaffected in waveform or amplitude when rods were pre-exposed in Ringer solution to light which was bright enough to suppress completely the circulating current but which bleached a negligible fraction of the photopigment. Furthermore, pre-incubation with the AM ester of the Ca2+ chelator BAPTA, although completely abolishing the slower components of fluorescence increase, had virtually no effect on the rapid rise. These results indicate that the rapid component, though triggered by rhodopsin bleaching, does

  20. Preventing stroke

    MedlinePlus

    Stroke - prevention; CVA - prevention; cerebral vascular accident - prevention; TIA - prevention, transient ischemic attack - prevention ... Clinical Cardiology; Council on Functional Genomics and ... Council on Hypertension. Guidelines for the primary prevention ...

  1. Effects of environmental pH and temperature on embryonic survival capacity and metabolic rates in the smallmouth salamander, Ambystoma texanum

    SciTech Connect

    Punzo, F.

    1983-10-01

    Although the deleterious effects of acid precipitation on forest ecosystems and fisheries have been documented, relatively little information is available on the effects of environmental pH in combination with temperature on the survival capacity and/or physiology of amphibians. Increased acidity resulting from acid precipitation common to the northwestern United States, can lead to increased mortality in the spotted salamander, Ambystoma maculatum. In view of the potentially significant deleterious effects of stressful pH conditions on amphibian survivorship and the relative paucity of data on this subject, the present study was conducted in order to ascertain the combined effects of temperature and pH on embryonic metabolic rates and survival capacity in the smallmouth salamander, Ambystoma texanum Mathes. No previous data on these parameters are available for this species.

  2. Ambient Temperature and Morbidity: A Review of Epidemiological Evidence

    PubMed Central

    Ye, Xiaofang; Wolff, Rodney; Yu, Weiwei; Vaneckova, Pavla; Pan, Xiaochuan

    2011-01-01

    Objective: In this paper, we review the epidemiological evidence on the relationship between ambient temperature and morbidity. We assessed the methodological issues in previous studies and proposed future research directions. Data sources and data extraction: We searched the PubMed database for epidemiological studies on ambient temperature and morbidity of noncommunicable diseases published in refereed English journals before 30 June 2010. Forty relevant studies were identified. Of these, 24 examined the relationship between ambient temperature and morbidity, 15 investigated the short-term effects of heat wave on morbidity, and 1 assessed both temperature and heat wave effects. Data synthesis: Descriptive and time-series studies were the two main research designs used to investigate the temperature–morbidity relationship. Measurements of temperature exposure and health outcomes used in these studies differed widely. The majority of studies reported a significant relationship between ambient temperature and total or cause-specific morbidities. However, there were some inconsistencies in the direction and magnitude of nonlinear lag effects. The lag effect of hot temperature on morbidity was shorter (several days) compared with that of cold temperature (up to a few weeks). The temperature–morbidity relationship may be confounded or modified by sociodemographic factors and air pollution. Conclusions: There is a significant short-term effect of ambient temperature on total and cause-specific morbidities. However, further research is needed to determine an appropriate temperature measure, consider a diverse range of morbidities, and to use consistent methodology to make different studies more comparable. PMID:21824855

  3. Growth, survival, longevity, and population size of the Big Mouth Cave salamander (Gyrinophilus palleucus necturoides) from the type locality in Grundy County, Tennessee, USA

    USGS Publications Warehouse

    Niemiller, Matthew L.; Glorioso, Brad M.; Fenolio, Dante B.; Reynolds, R. Graham; Taylor, Steven J.; Miller, Brian T.

    2016-01-01

    Salamander species that live entirely in subterranean habitats have evolved adaptations that allow them to cope with perpetual darkness and limited energy resources. We conducted a 26-month mark–recapture study to better understand the individual growth and demography of a population of the Big Mouth Cave Salamander (Gyrinophilus palleucus necturoides). We employed a growth model to estimate growth rates, age at sexual maturity, and longevity, and an open population model to estimate population size, density, detectability, and survival rates. Furthermore, we examined cover use and evidence of potential predation. Individuals probably reach sexual maturity in 3–5 years and live at least nine years. Survival rates were generally high (>75%) but declined during the study. More than 30% of captured salamanders had regenerating tails or tail damage, which presumably represent predation attempts by conspecifics or crayfishes. Most salamanders (>90%) were found under cover (e.g., rocks, trash, decaying plant material). Based on 11 surveys during the study, population size estimates ranged from 21 to 104 individuals in the ca. 710 m2 study area. Previous surveys indicated that this population experienced a significant decline from the early 1970s through the 1990s, perhaps related to silvicultural and agricultural practices. However, our data suggest that this population has either recovered or stabilized during the past 20 years. Differences in relative abundance between early surveys and our survey could be associated with differences in survey methods or sampling conditions rather than an increase in population size. Regardless, our study demonstrates that this population is larger than previously thought and is in no immediate risk of extirpation, though it does appear to exhibit higher rates of predation than expected for a species believed to be an apex predator of subterranean food webs.

  4. Longitudinal study on morbidity and mortality in white veal calves in Belgium

    PubMed Central

    2012-01-01

    Background Mortality and morbidity are hardly documented in the white veal industry, despite high levels of antimicrobial drug use and resistance. The objective of the present study was to determine the causes and epidemiology of morbidity and mortality in dairy, beef and crossbred white veal production. A total of 5853 calves, housed in 15 production cohorts, were followed during one production cycle. Causes of mortality were determined by necropsy. Morbidity was daily recorded by the producers. Results The total mortality risk was 5,3% and was significantly higher in beef veal production compared to dairy or crossbreds. The main causes of mortality were pneumonia (1.3% of the calves at risk), ruminal disorders (0.7%), idiopathic peritonitis (0.5%), enterotoxaemia (0.5%) and enteritis (0.4%). Belgian Blue beef calves were more likely to die from pneumonia, enterotoxaemia and arthritis. Detection of bovine viral diarrhea virus at necropsy was associated with chronic pneumonia and pleuritis. Of the calves, 25.4% was treated individually and the morbidity rate was 1.66 cases per 1000 calf days at risk. The incidence rate of respiratory disease, diarrhea, arthritis and otitis was 0.95, 0.30, 0.11 and 0.07 cases per 1000 calf days at risk respectively. Morbidity peaked in the first three weeks after arrival and gradually declined towards the end of the production cycle. Conclusions The present study provided insights into the causes and epidemiology of morbidity and mortality in white veal calves in Belgium, housed in the most frequent housing system in Europe. The necropsy findings, identified risk periods and differences between production systems can guide both veterinarians and producers towards the most profitable and ethical preventive and therapeutic protocols. PMID:22414223

  5. Fluctuations in a metapopulation of nesting four-toed salamanders, Hemidactylium scutatum, in the Great Smoky Mountains National Park, USA, 1999-2003

    USGS Publications Warehouse

    Corser, J.D.; Dodd, C.K., Jr.

    2004-01-01

    We tested two predictions associated with the hypothesis that certain populations of pond-breeding amphibians are structured into metapopulations using minimum relative abundance estimates of nesting four-toed salamanders (Hemidactylium scutatum Schlegel) from 11 different ponds in the Great Smoky Mountains National Park. Coefficients of variation (CV) for counts at individual ponds ranged from 0.25 to 1.26, and the overall mean CV at all 11 ponds was 0.34. Many pairs of ponds had negative correlations in abundance from 1999-2003, whereas others had various degrees of positive correlation (mean r = 0.29). Thus, nesting population size fluctuated semi-independently among the ponds from year to year, inferring the existence of inter-pond dispersal. The mean number of nesting females at a pond was negatively, but non-significantly, correlated (r = -0.27; P = 0.40; 10 d.f.) to the pond's isolation. Owing to physiological constraints on plethodontid salamander energetics, precipitation during the nesting season (February and March) appeared to play an important role (r = 0.78; P = 0.12; 4 d.f.) in the number of nesting females we observed. Unlike some other plethodontid salamander populations in more fragmented southern Appalachian forest ecosystems, this (meta)population within Great Smoky Mountains National Park does not appear to be declining.

  6. Infection Prevention in Transplantation.

    PubMed

    Pergam, Steven A

    2016-01-01

    The number of patients undergoing hematopoietic cell and solid organ transplantation are increasing every year, as are the number of centers both transplanting and caring for these patients. Improvements in transplant procedures, immunosuppressive regimens, and prevention of transplant-associated complications have led to marked improvements in survival in both populations. Infections remain one of the most important sources of excess morbidity and mortality in transplant, and therefore, infection prevention strategies are a critical element for avoiding these complications in centers caring for high-risk patients. This manuscript aims to provide an update of recent data on prevention of major healthcare-associated infections unique to transplantation, reviews the emergence of antimicrobial resistant infections, and discusses updated strategies to both identify and prevent transmission of these pathogens in transplant recipients. PMID:26820654

  7. Vaccine Preventable Disease on Campus.

    ERIC Educational Resources Information Center

    Bart, Kenneth J.

    1984-01-01

    While morbidity and mortality from vaccine preventable diseases have declined, some college students remain susceptible to measles, rubella, diptheria, tetanus, or polio. Colleges and universities have the opportunity to ensure protection of students, faculty, and employees by establishing and enforcing immunization requirements. (Author/DF)

  8. Postoperative respiratory morbidity: identification and risk factors.

    PubMed

    Mitchell, C; Garrahy, P; Peake, P

    1982-04-01

    Two hundred consecutive patients admitted for general surgery were studied prospectively to evaluate the contribution of risk factors to postoperative respiratory morbidity (PORM). PORM was expressed both in terms of individual clinical features present on the second postoperative day (when the incidence was greatest), and as an aggregate score incorporating many clinical features. The importance of recognised risk factors, such as previous respiratory disease, cigarette smoking, upper abdominal procedures and the duration of surgery was confirmed, in that these factors were associated with some of the individual clinical features of PORM. The relative importance and independent contribution of these risk factors were assessed by their association with the aggregate score. A naso-gastric tube (NGT) present for 24 hours postoperatively was the factor more associated with PORM. The NGT identified patients at risk more clearly than, and independently of, the next most important factor, upper abdominal surgery. The duration of surgery did not contribute to PORM after the influence of NGT and site of surgery had been considered. Previous respiratory disease predisposed to PORM, and was best identified by, in order of importance, an observed productive cough, a reduced one second forced expiratory volume, and purulent sputum. After the incidence of these factors had been considered, cigarette smoking and a history of a chronic productive cough did not contribute further to PORM. PMID:6952867

  9. Morbidity profile of steel pipe production workers

    PubMed Central

    Pandit, Kirti; Tiwari, Rajnarayan R.

    2008-01-01

    Objective: To study the different morbid conditions among steel pipe producing workers. Methods: The present cross-sectional study has been carried out among the workers of one of the steel pipes and tubes manufacturing factory of Gujarat. Hundred workers from the four major departments of the steel pipe production plant, namely welding, pressing machine, X-ray welding and loading/transportation department were covered. The information regarding demographic, occupational, clinical characteristics and diagnosis were recorded on a pre-designed proforma. Statistical analysis included calculation of percentages and proportions and was carried out using the statistical software Epi Info Version 3.3.2. Results: The mean age of the study subjects was found to be 38.7±7.1 years. The mean duration of exposure was found to be 9.0±3.4 years. Forty-four percent of the subjects had an upper respiratory tract infection, as evidenced by symptoms like dry cough, cough with rhinitis and cough with fever. Symptoms suggestive of allergic bronchitis were observed in 12% of the subjects while symptoms suggestive of heat stress such as prickly heat, dehydration, perspiration and pyrexia were observed in 13% of the subjects. PMID:20040985

  10. Psychological morbidity associated with motor vehicle accidents.

    PubMed

    Blanchard, E B; Hickling, E J; Taylor, A E; Loos, W R; Gerardi, R J

    1994-03-01

    Fifty victims of recent motor vehicle accidents (MVAs), who had sought medical attention after their accidents, were assessed for possible psychological morbidity as a result of the accident. Forty age, gender-matched controls were also assessed with the same instruments. Forty-six percent of the MVA victims met the criteria for current post-traumatic stress disorders (PTSD) as a result of the accident while 20% showed a sub-syndromal version (the reexperiencing symptom cluster plus either the avoidance/numbing cluster or the over-arousal cluster) of PTSD. Although all MVA victims showed some form of driving reluctance, only 1 S met the criteria for driving phobia. Those MVA victims who met the criteria for PTSD or sub-syndromal PTSD were significantly more likely to have experienced previous trauma, other than a serious MVA, and were more likely (P = 0.008) to have previously met the criteria for PTSD as a result of that trauma. Forty-eight percent of MVA victims who met the criteria for current PTSD also met the criteria for current major depression. Significantly more current MVA-PTSDs had suffered previous major depressive episodes. PMID:8192626

  11. [Preoperative management to reduce morbidity and mortality of hip fracture].

    PubMed

    Ferré, F; Minville, V

    2011-10-01

    Hip femur is extremely common in the elderly and is one of the most common reasons for admission in trauma care. The main reported causes of death after hip fracture were cardiovascular (29%), neurological (20%) and pulmonary. Large epidemiological studies have shown a relatively small decrease in mortality for 20 years despite an active approach to medical and surgical management. Yet 57% of deaths occurring within 30 days post-surgery are preventable because they are not related to a pre-existing disease. Preoperative management to optimize these patients could help to reduce morbidity and mortality and is thus a crucial issue. The anesthesia consultation is used to evaluate the perioperative risk, treat pain, manage treatment and stabilize the patient. An operative delay of more than 48hours after admission increases mortality. This period should not be prolonged by unnecessary investigations that will not change the perioperative management. The preoperative period is a key moment because it allows to choose the anesthetic technique. Even if this choice is controversial, continuous spinal anesthesia (titrated) do not modify the cardiovascular and neurological physiological balance of these precarious patients. PMID:21945704

  12. Maternal mortality and morbidity. Women's reproductive health in Tanzania.

    PubMed

    Alloo, F

    1994-01-01

    Sexuality is a taboo for women in a patriarchal society. Tanzania has inadequate reproductive health care. Aspects of reproductive health are dealt with in safe motherhood or maternal and child health programs. Tanzania's health policy is based on women as mothers; it does not refer to women's right. For women in Tanzania, reproductive health is the right to live. Thousands of Tanzanian women die every year due to maternal complications. In an effort to contribute to the improvement of the conditions in health institutions and the advancement of women's status in the country, the Tanzania Media Women's Association (TAMWA) and the Medical Women's Association of Tanzania (MEWATA) joined in the organization of a Reproductive Health Meeting in Dar es Salaam. At the conference, major factors causing maternal mortality and morbidity, such as complications of abortion, anaemia in pregnancy, hypertensive disorders in pregnancy and puerperal sepsis, were discussed. A World Health Organization (WHO) report indicated that maternal mortality in Tanzania was 200-400/100,000 live births, while a survey conducted by MEWATA showed that maternal deaths at the Muhimbili Medical Center in the capital were 754/100,000 live births in 1991. Many maternal deaths could be prevented if hospitals were be properly equipped. Tanzanian women's poor health results in large part from their low socioeconomic status, poor nutrition, lack of income and employment. TAMWA chairperson Fatma Alloo and Dr. Kimambo (Ministry of Health) endorsed a national women's health movement to demand a government commitment to a holistic reproductive health policy. PMID:12288398

  13. Stroke: morbidity, risk factors, and care in taiwan.

    PubMed

    Hsieh, Fang-I; Chiou, Hung-Yi

    2014-05-01

    Stroke is the third leading cause of death and the most common cause of complex disability in Taiwan. The annual age-standardized mortality rate of stroke is steadily decreasing between 2001 and 2012. The average years of potential life lost before age 70 for stroke is 13.8 years, ranked the fifth in the cause of death. Its national impact is predicted to be greater accompany aging population. The most common type of stroke was ischemic stroke in Taiwan. Small vessel occlusion was the majority of ischemic strokes subtype. Age, gender, hypertension, diabetes hyperlipidemia, obesity, atrial fibrillation, and smoking were important contributory factors to stroke morbidity. The standard treatment for acute ischemic stroke in Taiwan is providing the intravenous thrombolysis with recombinant tissue plasminogen activator (IV tPA) therapy for ischemic stroke patients within 3 hours of symptom onset. However, the rate of IV tPA therapy for patients with acute ischemic stroke is still low in Taiwan. Therefore, improving the public awareness of stroke warning signs and act on stroke and improving in-hospital critical pathway for thrombolysis would be the most important and urgent issues in Taiwan. To improve acute stroke care quality, a program of Breakthrough Series-Stroke activity was conducted from 2010 to 2011 and stroke centers were established in the medical centers. For the prevention of stroke, it was successful to increased annual smoke cessation rate through the 2009 Tobacco Hazards Prevention Act and decreased obesity rate through a nationwide weight-loss program conducted by Health Promotion Administration from 2011 to 2013 in Taiwan. PMID:24949310

  14. Risks from Worldwide Terrorism: Mortality and Morbidity Patterns and Trends

    SciTech Connect

    Bogen, K T; Jones, E D

    2005-01-25

    Worldwide data on terrorist incidents between 1968 and 2004 gathered by the RAND corporation and the Oklahoma City National Memorial Institute for the Prevention of Terrorism (MIPT) were assessed for patterns and trends in morbidity/mortality. The data involve a total of 19,828 events, 7,401 ''adverse'' events (each causing {ge}1 victim), 91,346 cases of casualty (either injury or death) and 25,408 deaths. Analyses revealed a number of interesting patterns and apparently significant trends. Most terror-related adverse events, casualties and deaths involved bombs and guns. Weapon-specific patterns and terror-related risk levels in Israel (ISR) have differed markedly from those of all other regions combined (AOR). ISR had a fatal fraction of casualties about half that of AOR, but has experienced relatively constant lifetime terror-related casualty risks on the order of 0.5%--a level 2 to 3 orders of magnitude more than those experienced in AOR, which have increased {approx}100-fold over the same period. Individual event fatality has increased steadily, the median increasing from 14 to 50%. Lorenz curves obtained indicate substantial dispersion among victim/event rates: about half of all victims were caused by the top 2% (10%) of harm-ranked events in OAR (ISR). Extreme values of victim/event rates were found to be well modeled by classic or generalized Pareto distributions, indicating that these rates have been as predictable as similarly extreme phenomena such as rainfall, sea levels, earthquakes, etc. This observation suggests that these extreme-value patterns may be used to improve strategies to prevent and manage risks associated with terror-related consequences.

  15. Youth Risk Behavior Surveillance--United States, 2009. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 59, Number SS-5

    ERIC Educational Resources Information Center

    Eaton, Danice K.; Kann, Laura; Kinchen, Steve; Shanklin, Shari; Ross, James; Hawkins, Joseph; Harris, William A.; Lowry, Richard; McManus, Tim; Chyen, David; Lim, Connie; Whittle, Lisa; Brener, Nancy D.; Wechsler, Howell

    2010-01-01

    Problem: Priority health-risk behaviors, which are behaviors that contribute to the leading causes of morbidity and mortality among youth and adults, often are established during childhood and adolescence, extend into adulthood, and are interrelated and preventable. Reporting Period Covered: September 2008-December 2009. Description of the…

  16. Youth Risk Behavior Surveillance--United States, 2005. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 55, Number SS-5

    ERIC Educational Resources Information Center

    Eaton, Danice K.; Kann, Laura; Kinchen, Steve; Ross, James; Hawkins, Joseph; Harris, William A.; Lowry, Richard; McManus, Tim; Chyen, David; Shanklin, Shari; Lim, Connie; Grunbaum, Jo Anne; Wechsler, Howell

    2006-01-01

    Problem: Priority health-risk behaviors, which contribute to the leading causes of morbidity and mortality among youth and adults, often are established during childhood and adolescence, extend into adulthood, are interrelated, and are preventable. Reporting Period Covered: October 2004-January 2006. Description of the System: The Youth Risk…

  17. Youth Risk Behavior Surveillance--United States, 2007. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 57, Number SS-4

    ERIC Educational Resources Information Center

    Eaton, Danice K.; Kann, Laura; Kinchen, Steve; Shanklin, Shari; Ross, James; Hawkins, Joseph; Harris, William A.; Lowry, Richard; McManus, Tim; Chyen, David; Lim, Connie; Brener, Nancy D.; Wechsler, Howell

    2008-01-01

    Problem: Priority health-risk behaviors, which are behaviors that contribute to the leading causes of morbidity and mortality among youth and adults, often are established during childhood and adolescence, extend into adulthood, are interrelated, and are preventable. Reporting Period Covered: January-December 2007. Description of the System: The…

  18. Youth Risk Behavior Surveillance--United States, 2011. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 61, Number 4

    ERIC Educational Resources Information Center

    Eaton, Danice K.; Kann, Laura; Kinchen, Steve; Shanklin, Shari; Flint, Katherine H.; Hawkins, Joseph; Harris, William A.; Lowry, Richard; McManus, Tim; Chyen, David; Whittle, Lisa; Lim, Connie; Wechsler, Howell

    2012-01-01

    Problem: Priority health-risk behaviors, which are behaviors that contribute to the leading causes of morbidity and mortality among youth and adults, often are established during childhood and adolescence, extend into adulthood, and are interrelated and preventable. Reporting Period Covered: September 2010-December 2011. Description of the…

  19. [The morbidity of students and the ways of its decreasing].

    PubMed

    Medvedkova, N I; Medvedkov, V D; Ashirova, S V

    2012-01-01

    The lower level of health of youth and unfavorable ecological environment inputs drastically into children morbidity. Hence, the important value has rationalization of life style and decrease of parents 'morbidity. The article presents the main components of the total structure of students' morbidity and outlines the ways of its decreasing. The changes in the education process and health of students, special medical group and students, released of physical exercises are demonstrated. The dynamics of morbidity of students over 20 years in the ecologically relatively clean environment and in industrial megalopolis is analyzed. PMID:23373343

  20. Jejunioleal Bypass Procedures in Morbid Obesity: Preoperative Psychological Findings

    ERIC Educational Resources Information Center

    Webb, Warren W.; And Others

    1976-01-01

    Seventy patients who averaged 155 percent overweight and requested jejunioleal bypass surgery as a treatment intervention for morbid obesity were studied preoperatively for prominent psychological characteristics. (Author)

  1. Morbid Obesity—The New Pandemic: Medical and Surgical Management, and Implications for the Practicing Gastroenterologist

    PubMed Central

    Cello, John P; Rogers, Stanley J

    2013-01-01

    The gastroenterologist, whether in academic or clinical practice, must face the reality that an increasingly large percentage of adult patients are morbidly obese. Morbid obesity is associated with significant morbidity and mortality including enhanced morbidity from cardiovascular, cerebrovascular, hepatobiliary and colonic diseases. Most of these associated diseases are actually preventable. Based on the 1991 NIH consensus conference criteria, for most patients with a body mass index (BMI=weight in kilograms divided by the height in meters squared) of 40 or more, or for patients with a BMI of 35 or more and significant health complications, surgery may be the only reliable option. Currently in the United States, over 250,000 bariatric surgical procedures are being performed annually. The practicing gastroenterologist in every community, large and small, must be familiar with the various surgical procedures together with their associated anatomic changes. These changes may dramatically increase the prevalence of nutritional deficiencies and profoundly alter the clinical and endoscopic approaches to diagnosis and management. PMID:23739585

  2. Idiopathic Polyhydramnios: Severity and Perinatal Morbidity.

    PubMed

    Wiegand, Samantha L; Beamon, Carmen J; Chescheir, Nancy C; Stamilio, David

    2016-06-01

    Objective To estimate the association between the severity of idiopathic polyhydramnios and adverse outcomes. Study Design Retrospective cohort study of deliveries at one hospital from 2000 to 2012 with an amniotic fluid index (AFI) measurement ≥24 + 0 weeks' gestation. Pregnancies complicated by diabetes, multiples, or fetal anomalies were excluded. Exposure was the degree of polyhydramnios: normal (AFI 5-24 cm), mild (≥ 24-30 cm), and moderate-severe (> 30 cm). Primary outcomes were perinatal mortality, neonatal intensive care unit (NICU) admission, and postpartum hemorrhage. Results There were 10,536 pregnancies: 10,188 with a normal AFI, 274 mild (78.74%), and 74 moderate-severe polyhydramnios (21.26%). Adverse outcomes were increased with idiopathic polyhydramnios: NICU admission (adjusted odds ratio [AOR] 3.71, 95% confidence interval [CI] 2.77-4.99), postpartum hemorrhage (AOR 15.81, 95% CI 7.82-31.96), macrosomia (AOR 3.41, 95% CI 2.61-4.47), low 5-minute Apgar score (AOR 2.60, 95% CI 1.57-4.30), and cesarean (AOR 2.16, 95% CI 1.74-2.69). There were increasing odds of macrosomia (mild: AOR 3.19, 95% CI 2.36-4.32; moderate-severe: AOR 4.44, 95% CI 2.53-7.79) and low 5-minute Apgar score (mild: AOR 2.24, 95% CI 1.23-4.08; moderate-severe: AOR 3.93, 95% CI 1.62-9.55) with increasing severity of polyhydramnios. Conclusion Idiopathic polyhydramnios is independently associated with increased risks of morbidity. There appears to be a dose-response relationship for neonatal macrosomia and low 5-minute Apgar score risks. PMID:26862725

  3. Travel and migration associated infectious diseases morbidity in Europe, 2008

    PubMed Central

    2010-01-01

    Background Europeans represent the majority of international travellers and clinicians encountering returned patients have an essential role in recognizing, and communicating travel-associated public health risks. Methods To investigate the morbidity of travel associated infectious diseases in European travellers, we analysed diagnoses with demographic, clinical and travel-related predictors of disease, in 6957 ill returned travellers who presented in 2008 to EuroTravNet centres with a presumed travel associated condition. Results Gastro-intestinal (GI) diseases accounted for 33% of illnesses, followed by febrile systemic illnesses (20%), dermatological conditions (12%) and respiratory illnesses (8%). There were 3 deaths recorded; a sepsis caused by Escherichia coli pyelonephritis, a dengue shock syndrome and a Plasmodium falciparum malaria. GI conditions included bacterial acute diarrhea (6.9%), as well as giardiasis and amebasis (2.3%). Among febrile systemic illnesses with identified pathogens, malaria (5.4%) accounted for most cases followed by dengue (1.9%) and others including chikungunya, rickettsial diseases, leptospirosis, brucellosis, Epstein Barr virus infections, tick-borne encephalitis (TBE) and viral hepatitis. Dermatological conditions were dominated by bacterial infections, arthropod bites, cutaneous larva migrans and animal bites requiring rabies post-exposure prophylaxis and also leishmaniasis, myasis, tungiasis and one case of leprosy. Respiratory illness included 112 cases of tuberculosis including cases of multi-drug resistant or extensively drug resistant tuberculosis, 104 cases of influenza like illness, and 5 cases of Legionnaires disease. Sexually transmitted infections (STI) accounted for 0.6% of total diagnoses and included HIV infection and syphilis. A total of 165 cases of potentially vaccine preventable diseases were reported. Purpose of travel and destination specific risk factors was identified for several diagnoses such as Chagas

  4. Relative contribution of rod and cone inputs to bipolar cells and ganglion cells in the tiger salamander retina.

    PubMed

    Hensley, S H; Yang, X L; Wu, S M

    1993-06-01

    1. The relative contribution of rod and cone inputs to bipolar and ganglion cells were studied by comparing the response-irradiance relations, spectral sensitivities, and response waveforms of these neurons recorded from the isolated, flat-mounted tiger salamander retina under dark-adapted conditions. 2. Bipolar cells could be differentiated both on the basis of the polarity of the light response and on their relative rod/cone input. Thus some depolarizing bipolar cells appeared more strongly influenced by rod input (DBCR), whereas others were more influenced by cone input (DBCC). Similarly, hyperpolarizing bipolar cells could be divided into those that received rod-dominant input (HBCR) or cone-dominant input (HBCC). 3. The light onset response of sustained-ON ganglion cells reflected both rod-dominant input from DBCRs and cone-dominant input from DBCCs. 4. OFF ganglion cells displayed both a rod-dominant sustained light offset response and a cone-dominant transient light offset response, suggesting input from both HBCRs and HBCCs. 5. In ON-OFF ganglion cells, the light onset response was strongly rod dominated and was presumably mediated by DBCRs, whereas the light offset response displayed both rod and cone influence, suggesting input from HBCRs and HBCCs. The contribution of cones to the light onset response of ON-OFF ganglion cells was only observed in the presence of a rod-adapting background light. 6. A suppression of the light offset responses of OFF and ON-OFF ganglion cells was observed, which was dependent both on the wavelength and irradiance of the light stimulus. 7. These results indicate that the photoreceptor inputs to bipolar cells in the tiger salamander retina are segregated such that they form separate rod-dominant and cone-dominant pathways. Thus the response properties of the different types of ganglion cells are influenced not only by the excitatory and inhibitory inputs they receive from the bipolar and amacrine cells but also whether these

  5. Work and lifestyle factors associated with morbidity of electronic women workers in Selangor, Malaysia.

    PubMed

    Hwei-Mian Lim; Heng-Leng Chee; Mirnalini Kandiah; Sharifah Zainiyah Syed Yahya; Rashidah Shuib

    2002-01-01

    The objective of this study was to identify sociodemographic, work, living arrangement and lifestyle factors associated with morbidity of electronics women workers in selected factories in Selangor, Malaysia. The research design was a cross-sectional questionnaire-based survey. Most of the 401 respondents were young single Malay women. Morbidity was high as 85.5% of the women reported experiencing at least one chronic health problem, and 25.7% said that an illness or injury prevented them from carrying out normal activities within the last two weeks. Major acute illness symptoms were the common cold, backache, and diarrhoea while chronic health problems such as persistent headache, eye problems, menstrual problems, and persistent backache were also reported. After logistic regression, chronic health problems was significantly associated with room sharing; while illness that prevented normal activities within the last two weeks was significantly associated with overtime work and exercise. Further research is recommended to understand the complex inter-relationship between morbidity and working and living conditions. PMID:12862411

  6. Morbidity and Hospitalizations of Adults with Down Syndrome

    ERIC Educational Resources Information Center

    Tenenbaum, Ariel; Chavkin, Maor; Wexler, Isaiah D.; Korem, Maya; Merrick, Joav

    2012-01-01

    Over the last decade a significant increase in the life expectancy of people with Down syndrome (DS) has been observed, which has caused a higher incidence of morbidity as they age. However, there is a lack of literature regarding morbidity and hospitalization of adults with DS. Analysis of 297 hospitalizations of 120 adults with DS aged 18-73…

  7. TRICARE Program; surgery for morbid obesity. Final rule.

    PubMed

    2011-02-14

    This final rule adds a definition of Bariatric Surgery, amends the definition of Morbid Obesity, and revises the language relating to the treatment of morbid obesity to allow benefit consideration for newer bariatric surgical procedures that are considered appropriate medical care. The final rule removes language that specifically limits the types of surgical procedures to treat co-morbid conditions associated with morbid obesity and retains the TRICARE Program exclusion of non-surgical interventions related to morbid obesity, obesity and/or weight reduction. This final rule is necessary to allow coverage for other surgical procedures that reduce or resolve co-morbid conditions associated with morbid obesity and the use of the Body Mass Index (BMI), which is the more accurate measure for excess weight to estimate relative risk of disease. As new technologies or procedures evolve from investigational into generally accepted norms for medical practice, the statutes and regulations governing the TRICARE Program allow the Department to offer beneficiaries these new benefits. These changes are required in order to allow the Department to provide these newer technologies and procedures for the treatment of morbid obesity as they evolve. PMID:21348347

  8. Role of the Neuregulin Signaling Pathway in Nicotine Dependence and Co-morbid Disorders.

    PubMed

    Fisher, Miranda L; Loukola, Anu; Kaprio, Jaakko; Turner, Jill R

    2015-01-01

    Smoking is currently the leading cause of preventable death in the United States and is responsible for over four million deaths annually worldwide. Therefore, there is a vast clinical unmet need with regards to therapeutics targeting smoking cessation. This is even more apparent when examining smokers co-morbid with psychiatric illness, as rates of smoking in this population are ~4× higher than in the general population. Examining common genetic and molecular signaling pathways impinging upon both smoking behavior and psychiatric illness will lead to a better understanding of co-morbid disorders and potential development of novel therapeutics. Studies have implicated the Neuregulin Signaling Pathway in the pathophysiology of a number of psychiatric illnesses. Additionally, recent studies have also shown an association between the Neuregulin Signaling Pathway and smoking behaviors. This review outlines basic mechanisms of the Neuregulin Signaling Pathway and how it may be exploited for precision medicine approaches in treating nicotine dependence and mental illness. PMID:26472527

  9. Psychiatric Co-morbidity in Women Presenting across the Continuum of Disordered Eating

    PubMed Central

    Aspen, Vandana; Weisman, Hannah; Vannucci, Anna; Nafiz, Najia; Gredysa, Dana; Kass, Andrea; Trockel, Mickey; Wilfley, Denise E.; Taylor, C. Barr

    2014-01-01

    Objective To compare the prevalence and correlates of psychiatric co-morbidity across a large sample of college women without an eating disorder, those at high risk for an eating disorder and women diagnosed using DSM-5 criteria for an eating disorder. Participants 549 college age women aged 18–25. Methods Data from the Eating Disorder Examination, the Structured Clinical Interview for DSM-IV Axis I disorders and self-report questionnaires were analyzed using logistic regression for categorical data and ANCOVA for continuous measures. Results Eating disordered symptomatology was strongly associated with anxiety disorders, mood disorders and insomnia. These co-morbidities (type and severity) tend to increase with eating disorder symptom severity. Conclusions Prevention and treatment programs for eating disorders need to address the high levels of mood, anxiety and sleep problems in this population. The findings on insomnia are novel and suggest that sleep disturbance may play an integral role in eating-related difficulties. PMID:25462028

  10. Putting the "M" back in the Maternal and Child Health Bureau: reducing maternal mortality and morbidity.

    PubMed

    Lu, Michael C; Highsmith, Keisher; de la Cruz, David; Atrash, Hani K

    2015-07-01

    Maternal mortality and severe morbidity are on the rise in the United States. A significant proportion of these events are preventable. The Maternal Health Initiative (MHI), coordinated by the Maternal and Child Health Bureau at the Health Resources and Services Administration, is intensifying efforts to reduce maternal mortality and severe morbidity in the U.S. Through a public-private partnership, MHI is taking a comprehensive approach to improving maternal health focusing on five priority areas: improving women's health before, during and beyond pregnancy; improving the quality and safety of maternity care; improving systems of maternity care including both clinical and public health systems; improving public awareness and education; and improving surveillance and research. PMID:25626713

  11. Hepatic Parenchymal Preservation Surgery: Decreasing Morbidity and Mortality Rates in 4,152 Resections for Malignancy

    PubMed Central

    Kingham, T Peter; Correa-Gallego, Camilo; D'Angelica, Michael I; Gönen, Mithat; DeMatteo, Ronald P; Fong, Yuman; Allen, Peter J; Blumgart, Leslie H; Jarnagin, William R

    2015-01-01

    Background Liver resection is used to treat primary and secondary malignancies. Historically, these procedures were associated with significant complications, which may affect cancer-specific outcome. This study analyzes the changes in morbidity and mortality after hepatic resection over time. Study Design Records of all patients undergoing liver resection for a malignant diagnosis from 1993 to 2012 at Memorial Sloan Kettering were analyzed. Patients were divided into early (1993-1999), middle (2000-2006), and recent (2007-2012) eras. Major hepatectomy was defined as resection of 3 or more segments. Univariate and multivariate analyses were made with t-tests or Mann-Whitney tests. Results 3,875 patients underwent 4,152 resections for malignancy. The most common diagnosis was metastatic colorectal cancer (n=2,476, 64% of patients). Over the study period, 90-day mortality rate decreased from 5% to 1.6% (p<0.001). Perioperative morbidity decreased from 53% to 20% (p<0.001). The percentage of major hepatectomies decreased from 66% to 36% (p<0.001). The rate of perioperative transfusion decreased from 51% to 21% (p<0.001). The spectrum of perioperative morbidity changed markedly over time, with abdominal infections (43% of complications) overtaking cardiopulmonary complications (22% of complications). Peak postoperative bilirubin (OR 1.1, p<0.001), blood loss (OR 1.5, p=0.001), major hepatectomy (OR 1.3, p=0.031), and concurrent partial colectomy (OR 2.4, p<0.001) were independent predictors of perioperative morbidity. The mortality associated with trisectionectomy (6%) and right hepatectomy (3%) remained unchanged over time. Conclusions Morbidity and mortality rates after partial hepatectomy for cancer have decreased substantially as the major hepatectomy rate dropped. Encouraging parenchymal preservation and preventing abdominal infections are vital for continued improvement of liver resection outcomes. PMID:25667141

  12. Cholesterol testing among men and women with disability: the role of morbidity

    PubMed Central

    Lofters, Aisha K; Guilcher, Sara JT; Webster, Lauren; Glazier, Richard H; Jaglal, Susan B; Bayoumi, Ahmed M

    2016-01-01

    Purpose Despite more frequent use of health services by people living with disability, the quality of preventive care received may be suboptimal. In this retrospective cohort study, we used administrative data to examine the relationship between cholesterol testing and levels of disability and morbidity among women and men in Ontario, Canada. Methods We linked multiple provincial-level databases in this study. In stratified analyses for women and men, we used multivariable logistic regression to examine differences in cholesterol testing, and we tested for an interaction effect between disability and morbidity. In a secondary analysis, we tested for a three-way interaction between sex, disability, and morbidity on the entire cohort. Results There was an interaction between morbidity and disability for both women and men. Women and men with no chronic conditions appeared to be least likely to be up-to-date on cholesterol testing, and among this group, those with moderate disability were more likely to be up-to-date on cholesterol testing than those with no disability (adjusted odds ratio [AOR] =1.51; 95% confidence interval [CI] 1.20–1.90 for women; AOR =1.16; 95% CI 1.00–1.34 for men). Among women and men who had one chronic condition, having severe disability put them at significant disadvantage versus those with no disability. Only 58.5% of men with no disability and no chronic conditions were up-to-date on cholesterol testing. Conclusion An intermediate level of health care need (reflected in this study as level of disability and level of morbidity) may provide a benefit for cholesterol testing, and conversely, health care needs that are too few or too great may negatively affect testing. Public health and practice-based interventions need to be explored to address these findings. PMID:27621668

  13. Nonlinearity in Demographic and Behavioral Determinants of Morbidity

    PubMed Central

    Norris, Jean C; Van der laan, Mark J; Lane, Sylvia; Anderson, James N; Block, Gladys

    2003-01-01

    Objective To examine nonlinearity of determinants of morbidity in the United States Data Sources A secondary analysis of data on individuals with dietary data from the Cancer Epidemiology Supplement and National Health Interview Survey (NHIS) 1987, a cross-sectional, stratified random sample of the U.S. population (n=22,080). Study Design A statistical exploration using additive multiple regression models. Methods A Morbidity Index (0–30 points), derived from 1987 National Health Interview Survey data, combines number of conditions, hospitalizations, sick days, doctor visits, and degree of disability. Behavioral (health habits) variables were added to multivariate models containing demographic terms, with Morbidity Index and Self-assessed Health outcomes (n=17,612). Tables and graphs compare models of morbidity with self-assessed health models, with and without behavioral terms. Graphs illustrate curvilinear relationships. Principal Findings Morbidity and health are associated nonlinearly with age, race, education, and income, as well as alcohol, diet change, vitamin supplement use, body mass index (BMI), marital status/living arrangement, and smoking. Diet change and supplement use, education, income, race/ethnicity, and age relate differently to self-assessed health status than to morbidity. Morbidity is strongly associated with income up to about $15,000 above poverty. Additional income predicts no further reduction in morbidity. Better health is strongly related to both higher income and education. After controlling for income, black race does not predict morbidity, but remains associated with lower self-assessed health. Conclusions Good health habits, as captured in these models, are associated with a 10–20-year delay in onset and progression of morbidity. PMID:14727798

  14. Prevention in developing countries.

    PubMed

    Black, R E

    1990-01-01

    Developing countries have implemented primary health care programs directed primarily at prevention and management of important infectious and nutritional problems of children. Successful programs have emphasized the need for individual and community involvement and have been characterized by responsible government policies for equitable implementation of efficacious and cost-effective health interventions. Unfortunately, developing countries must also face increases in the chronic disease and social problems commonly associated with industrialized countries. Prevention efforts, for example, to reduce tobacco smoking, to modify the diet, to reduce injuries, or to avert environmental contamination, are needed to contain future morbidity and rapidly increasing medical care costs. Developing countries can build on their successful approaches to program implementation and add other measures directed at preservation of health and prevention of disease in adult as well as child populations. PMID:2231055

  15. Initial characterization of the large genome of the salamander Ambystoma mexicanum using shotgun and laser capture chromosome sequencing.

    PubMed

    Keinath, Melissa C; Timoshevskiy, Vladimir A; Timoshevskaya, Nataliya Y; Tsonis, Panagiotis A; Voss, S Randal; Smith, Jeramiah J

    2015-01-01

    Vertebrates exhibit substantial diversity in genome size, and some of the largest genomes exist in species that uniquely inform diverse areas of basic and biomedical research. For example, the salamander Ambystoma mexicanum (the Mexican axolotl) is a model organism for studies of regeneration, development and genome evolution, yet its genome is ~10× larger than the human genome. As part of a hierarchical approach toward improving genome resources for the species, we generated 600 Gb of shotgun sequence data and developed methods for sequencing individual laser-captured chromosomes. Based on these data, we estimate that the A. mexicanum genome is ~32 Gb. Notably, as much as 19 Gb of the A. mexicanum genome can potentially be considered single copy, which presumably reflects the evolutionary diversification of mobile elements that accumulated during an ancient episode of genome expansion. Chromosome-targeted sequencing permitted the development of assemblies within the constraints of modern computational platforms, allowed us to place 2062 genes on the two smallest A. mexicanum chromosomes and resolves key events in the history of vertebrate genome evolution. Our analyses show that the capture and sequencing of individual chromosomes is likely to provide valuable information for the systematic sequencing, assembly and scaffolding of large genomes. PMID:26553646

  16. Temporal patterns and selectivity in the unitary responses of olfactory receptors in the tiger salamander to odor stimulation.

    PubMed

    Baylin, F

    1979-07-01

    Temporal patterns and selectivity in unitary responses of 100 single olfactory receptors in the tiger salamander to odor stimulation were investigated. An olfactometer which permitted control of stimulus concentration, duration, and flow rate was calibrated with a gas chromatograph. Stimulus pulses were monitored by recording the electroolfactogram from the surface of the olfactory epithelium. Both diphasic and triphasic spikes were recorded extracellularly. No discernible differences in types of responses, reproducibility of responses, and cross-unit distribution of spontaneous rates distinguished diphasic from triphasic units. The cross-unit selectivity in responses to the seven olfactory stimulants used and the range of odorant concentrations which effectively evoked these responses suggest variations in types and number of types of receptive sites on each cell. Temporal patterns in the unitary responses were generally less complex than those observed in the olfactory bulb. Phasic stimulations evoked phasic patterns. Tonic stimulations evoked phasic/tonic patterns. Occasionally poststimulus depressions or elevations in firing rates were observed. The nature of these patterns varied somewhat with odorant concentration for a particular unit. PMID:479819

  17. The effects of simulated solar UVB radiation on early developmental stages of the Northwestern Salamander (Ambystoma gracile) from three lakes

    USGS Publications Warehouse

    Calfee, Robin D.; Little, Edward E.; Pearl, Christopher A.; Hoffman, Robert L.

    2010-01-01

    Solar ultraviolet radiation (UV) has received much attention as a factor that could play a role in amphibian population declines. UV can be hazardous to some amphibians, but the resultant effects depend on a variety of environmental and behavioral factors. In this study, the potential effects of UV on the Northwestern Salamander, Ambystoma gracile, from three lakes were assessed in the laboratory using a solar simulator. We measured the survival of embryos and the survival and growth of larvae exposed to four UV treatments in controlled laboratory studies, the UV absorbance of egg jelly, oviposition depths in the lakes, and UV absorbance in water samples from the three lakes. Hatching success of embryos decreased in the higher UV treatments as compared to the control treatments, and growth of surviving larvae was significantly reduced in the higher UVB irradiance treatments. The egg jelly exhibited a small peak of absorbance within the UVB range (290–320 nm). The magnitude of UV absorbance differed among egg jellies from the three lakes. Oviposition depths at the three sites averaged 1.10 m below the water surface. Approximately 66% of surface UVB radiation was attenuated at 10-cm depth in all three lakes. Results of this study indicate that larvae may be sensitive to UVB exposure under laboratory conditions; however, in field conditions the depths of egg deposition in the lakes, absorbance of UV radiation by the water column, and the potential for behavioral adjustments may mitigate severe effects of UV radiation.

  18. Initial characterization of the large genome of the salamander Ambystoma mexicanum using shotgun and laser capture chromosome sequencing

    PubMed Central

    Keinath, Melissa C.; Timoshevskiy, Vladimir A.; Timoshevskaya, Nataliya Y.; Tsonis, Panagiotis A.; Voss, S. Randal; Smith, Jeramiah J.

    2015-01-01

    Vertebrates exhibit substantial diversity in genome size, and some of the largest genomes exist in species that uniquely inform diverse areas of basic and biomedical research. For example, the salamander Ambystoma mexicanum (the Mexican axolotl) is a model organism for studies of regeneration, development and genome evolution, yet its genome is ~10× larger than the human genome. As part of a hierarchical approach toward improving genome resources for the species, we generated 600 Gb of shotgun sequence data and developed methods for sequencing individual laser-captured chromosomes. Based on these data, we estimate that the A. mexicanum genome is ~32 Gb. Notably, as much as 19 Gb of the A. mexicanum genome can potentially be considered single copy, which presumably reflects the evolutionary diversification of mobile elements that accumulated during an ancient episode of genome expansion. Chromosome-targeted sequencing permitted the development of assemblies within the constraints of modern computational platforms, allowed us to place 2062 genes on the two smallest A. mexicanum chromosomes and resolves key events in the history of vertebrate genome evolution. Our analyses show that the capture and sequencing of individual chromosomes is likely to provide valuable information for the systematic sequencing, assembly and scaffolding of large genomes. PMID:26553646

  19. Extreme Performance and Functional Robustness of Movement are Linked to Muscle Architecture: Comparing Elastic and Nonelastic Feeding Movements in Salamanders.

    PubMed

    Scales, Jeffrey A; Stinson, Charlotte M; Deban, Stephen M

    2016-07-01

    Muscle-powered movements are limited by the contractile properties of muscles and are sensitive to temperature changes. Elastic-recoil mechanisms can both increase performance and mitigate the effects of temperature on performance. Here, we compare feeding movements in two species of plethodontid salamanders, Bolitoglossa franklini and Desmognathus quadramaculatus, across a range of body temperatures (5-25°C) to better understand the mechanism of elastically powered, thermally robust movements. Bolitoglossa exhibited ballistic, elastically powered tongue projection with a maximum muscle mass specific power of 4,642 W kg(-1) while Desmognathus demonstrated nonballistic, muscle-powered tongue projection with a maximum power of 359 W kg(-1) . Tongue-projection performance in Bolitoglossa was more thermally robust than that of Desmognathus, especially below 15°C. The improved performance and thermal robustness of Bolitoglossa was associated with morphological changes in the projector muscle, including elaborated collagen aponeuroses and the absence of myofibers attaching directly to the tongue skeleton. The elongated aponeuroses likely increase the capacity for elastic energy storage, and the lack of myofibers inserting on the tongue skeleton permits ballistic projection. These results suggest that relatively simple changes in myofiber architecture and the amount of connective tissue can improve the performance and functional robustness of movements in the face of environmental challenges such as variable temperature. PMID:27320361

  20. Movement, demographics, and occupancy dynamics of a federally-threatened salamander: evaluating the adequacy of critical habitat.

    PubMed

    Bendik, Nathan F; McEntire, Kira D; Sissel, Blake N

    2016-01-01

    Critical habitat for many species is often limited to occupied localities. For rare and cryptic species, or those lacking sufficient data, occupied habitats may go unrecognized, potentially hindering species recovery. Proposed critical habitat for the aquatic Jollyville Plateau salamander (Eurycea tonkawae) and two sister species were delineated based on the assumption that surface habitat is restricted to springs and excludes intervening stream reaches. To test this assumption, we performed two studies to understand aspects of individual, population, and metapopulation ecology of E. tonkawae. First, we examined movement and population demographics using capture-recapture along a spring-influenced stream reach. We then extended our investigation of stream habitat use with a study of occupancy and habitat dynamics in multiple headwater streams. Indications of extensive stream channel use based on capture-recapture results included frequent movements of >15 m, and high juvenile abundance downstream of the spring. Initial occupancy of E. tonkawae was associated with shallow depths, maidenhair fern presence and low temperature variation (indicative of groundwater influence), although many occupied sites were far from known springs. Additionally, previously dry sites were three times more likely to be colonized than wet sites. Our results indicate extensive use of stream habitats, including intermittent ones, by E. tonkawae. These areas may be important for maintaining population connectivity or even as primary habitat patches. Restricting critical habitat to occupied sites will result in a mismatch with actual habitat use, particularly when assumptions of habitat use are untested, thus limiting the potential for recovery. PMID:26998413

  1. Multiple nuclear gene sequences identify phylogenetic species boundaries in the rapidly radiating clade of Mexican ambystomatid salamanders.

    PubMed

    Weisrock, David W; Shaffer, H Bradley; Storz, Brian L; Storz, Shonna R; Voss, S Randal

    2006-08-01

    Delimiting the boundaries of species involved in radiations is critical to understanding the tempo and mode of lineage formation. Single locus gene trees may or may not reflect the underlying pattern of population divergence and lineage formation, yet they constitute the vast majority of the empirical data in species radiations. In this study we make use of an expressed sequence tag (EST) database to perform nuclear (nDNA) and mitochondrial (mtDNA) genealogical tests of species boundaries in Ambystoma ordinarium, a member of an adaptive radiation of metamorphic and paedomorphic salamanders (the Ambystoma tigrinum complex) that have diversified across terrestrial and aquatic environments. Gene tree comparisons demonstrate extensive nonmonophyly in the mtDNA genealogy of A. ordinarium, while seven of eight independent nuclear loci resolve the species as monophyletic or nearly so, and diagnose it as a well-resolved genealogical species. A differential introgression hypothesis is supported by the observation that western A. ordinarium localities contain mtDNA haplotypes that are identical or minimally diverged from haplotypes sampled from a nearby paedomorphic species, Ambystoma dumerilii, while most nDNA trees place these species in distant phylogenetic positions. These results provide a strong example of how historical introgression can lead to radical differences between gene trees and species histories, even among currently allopatric species with divergent life history adaptations and morphologies. They also demonstrate how EST-based nuclear resources can be used to more fully resolve the phylogenetic history of species radiations. PMID:16842422

  2. Lineage divergence and speciation in the Web-toed Salamanders (Plethodontidae: Hydromantes) of the Sierra Nevada, California.

    PubMed

    Rovito, Sean M

    2010-10-01

    Peripatric speciation and the importance of founder effects have long been controversial, and multilocus sequence data and coalescent methods now allow hypotheses of peripatric speciation to be tested in a rigorous manner. Using a multilocus phylogeographical data set for two species of salamanders (genus Hydromantes) from the Sierra Nevada of California, hypotheses of recent divergence by peripatric speciation and older, allopatric divergence were tested. Phylogeographical analysis revealed two divergent lineages within Hydromantes platycephalus, which were estimated to have diverged in the Pliocene. By contrast, a low-elevation species, Hydromantes brunus, diverged from within the northern lineage of H. platycephalus much more recently (mid-Pleistocene), during a time of major climatic change in the Sierra Nevada. Multilocus species tree estimation and coalescent estimates of divergence time, migration rate, and growth rate reject a scenario of ancient speciation of H. brunus with subsequent gene flow and introgression from H. platycephalus, instead supporting a more recent divergence with population expansion. Although the small, peripheral distribution of H. brunus suggests the possibility of peripatric speciation, the estimated founding population size of the species was too large to have allowed founder effects to be important in its divergence. These results provide evidence for both recent speciation, most likely tied to the climatic changes of the Pleistocene, and older lineage divergence, possibly due to geological events, and add to evidence that Pleistocene glacial cycles were an important driver of diversification in the Sierra Nevada. PMID:20854412

  3. Movement, demographics, and occupancy dynamics of a federally-threatened salamander: evaluating the adequacy of critical habitat

    PubMed Central

    McEntire, Kira D.; Sissel, Blake N.

    2016-01-01

    Critical habitat for many species is often limited to occupied localities. For rare and cryptic species, or those lacking sufficient data, occupied habitats may go unrecognized, potentially hindering species recovery. Proposed critical habitat for the aquatic Jollyville Plateau salamander (Eurycea tonkawae) and two sister species were delineated based on the assumption that surface habitat is restricted to springs and excludes intervening stream reaches. To test this assumption, we performed two studies to understand aspects of individual, population, and metapopulation ecology of E. tonkawae. First, we examined movement and population demographics using capture-recapture along a spring-influenced stream reach. We then extended our investigation of stream habitat use with a study of occupancy and habitat dynamics in multiple headwater streams. Indications of extensive stream channel use based on capture-recapture results included frequent movements of >15 m, and high juvenile abundance downstream of the spring. Initial occupancy of E. tonkawae was associated with shallow depths, maidenhair fern presence and low temperature variation (indicative of groundwater influence), although many occupied sites were far from known springs. Additionally, previously dry sites were three times more likely to be colonized than wet sites. Our results indicate extensive use of stream habitats, including intermittent ones, by E. tonkawae. These areas may be important for maintaining population connectivity or even as primary habitat patches. Restricting critical habitat to occupied sites will result in a mismatch with actual habitat use, particularly when assumptions of habitat use are untested, thus limiting the potential for recovery. PMID:26998413

  4. Experimental analysis of trout effects on survival, growth, and habitat use of two species of western Ambystomatid salamanders

    USGS Publications Warehouse

    Tyler, T.; Liss, W.J.; Hoffman, Robert L.; Ganio, L.

    1998-01-01

    Introduced fish have been implicated as reducing abundance or eliminating ambystomatid salamanders from montane lakes in western North America. We tested the null hypotheses that survivorship, growth, and refuge use of larvae reared for 30 d did not differ between artificial ponds with trout and without trout. Larval survivorship for both A. macrodactylum and A. gracile was significantly lower in ponds with trout than in fishless ponds. Both species had significantly lower snout-vent lengths in ponds with trout than in fishless ponds at the conclusion of the experiments. Only A. gracile had significantly lower body weight in ponds with trout than in ponds without trout. For both species, substrate locations of larvae were significantly influenced by trout at the conclusion of the experiments. Larvae of both species were found in a narrower range of substrates in ponds with fish than in control ponds. Our findings support inferences from field studies that the presence of trout have negative impacts on larval A. macrodactylum and A. gracile.

  5. Bedside placement of a retrievable inferior vena cava filter in a morbidly obese patient guided by modified IVUS approach.

    PubMed

    Patel, Nishit; Saucedo, Jorge

    2012-12-01

    Deep vein thrombosis and pulmonary embolism are major causes of morbidity and mortality in trauma patients. Anticoagulation therapy is often contraindicated in these patient populations. The retrievable inferior vena cava (IVC) filter provides a good option for preventing pulmonary embolism in the immediate injury and postoperative periods. Bedside IVC filter placement by guidance of intravascular ultrasound eliminates the risk of transportation; it is safe, efficient, and cost effective. We hereby present a case of bedside IVC filter placement in a morbidly obese patient with modified intravascular ultrasound approach. PMID:23220991

  6. Chopart joint injury: a study of outcome and morbidity.

    PubMed

    van Dorp, Karin B; de Vries, Mark R; van der Elst, Maarten; Schepers, Tim

    2010-01-01

    Injuries involving the Chopart joint complex are relatively rare and frequently missed or misdiagnosed, often leading to a poor functional outcome. This study was performed to determine the outcome and morbidity in patients with Chopart joint injuries, and to increase awareness of this severe injury. Patients with a Chopart dislocation or fracture-dislocation, treated between January 2004 and January 2010, were identified using the appropriate diagnosis code and reviewing all radiographs of patients diagnosed with hindfoot or midfoot injuries treated at our institution. Data on patient characteristics, trauma mechanism, delay, and treatment were collected using patient files, operation reports, and by reviewing radiographs. Outcome was determined using the American Orthopaedic Foot & Ankle Society midfoot score and a visual analog scale satisfaction score, in patients with a minimum follow-up of 6 months. Nine patients (1.5 per year) were identified, including 6 women. The mean patient age was 41.6 ± 25.1 years. The trauma mechanism was sprain or sports injury in 5 (55.6%), motor vehicle accident in 3 (33.33%), and a fall from height in 1 (11.11%) case. Seven patients with an average follow-up of 31.3 ± 19.2 months reported a mean American Orthopaedic Foot & Ankle Society midfoot score of 72 (range, 32-100) points and a mean visual analog scale score of 7.1 (range, 5-10). Four (57.14%) patients still experienced pain or had limitations in daily activities at the time of the final follow-up. This study supports the conclusion of previous studies, which stated that a higher level of awareness is needed to prevent permanent disability. PMID:21035040

  7. Does Time of Delivery Influence the Risk of Neonatal Morbidity?

    PubMed

    Brookfield, Kathleen F; O'Malley, Katharine; El-Sayed, Yasser Y; Blumenfeld, Yair J; Butwick, Alexander J

    2016-04-01

    Objective To examine whether time of delivery influences the risk of neonatal morbidity among women with singleton pregnancies. Study Design Secondary analysis of data from the Maternal Fetal Medicine Units Network Factor V Leiden Mutation study. We categorized time of delivery as day (07:00-16:59), evening (17:00-23:59), and overnight (midnight-06:59). Severe neonatal morbidity was defined by at least one of the following: respiratory distress syndrome, transient tachypnea of the newborn, sepsis, seizures, neonatal intensive care admission, or a 5-minute APGAR ≤3. We calculated frequencies of severe neonatal morbidity by time of delivery. Multivariate analysis was performed to determine whether time of delivery was independently associated with severe neonatal morbidity. Results Among 4,087 women, 1,917 (46.9%) delivered during the day, 1,140 (27.9%) delivered in the evening, and 1,030 (25.2%) delivered overnight. We observed no significant differences in the rates of neonatal morbidity between delivery time periods (day: 12.3%; evening: 12.8%; overnight: 12.6%; p = 0.9). No significant association was observed between time of delivery and neonatal morbidity after adjustment for maternal, obstetric, and peripartum factors. Conclusion Our findings suggest that time of delivery is not associated with severe neonatal morbidity. PMID:26595143

  8. Burden of lymphatic filariasis morbidity in an area of low endemicity in Brazil.

    PubMed

    Netto, Maria José; Bonfim, Cristine; Brandão, Eduardo; Aguiar-Santos, Ana Maria; Medeiros, Zulma

    2016-11-01

    The Global Programme to Eliminate Lymphatic Filariasis has two main components: interrupting transmission of lymphatic filariasis (LF) and managing morbidity and preventing disability. However, interventions to prevent and manage LF-related disabilities in endemic communities have been of limited extent. The aim of this study was to describe the prevalence of morbidity and its correlation with filarial infection, thereby filling a gap that existed regarding the data on morbidity in Brazil. Presence of Wuchereria bancrofti microfilaria was investigated using the thick smear technique. Information on parasitosis-related clinical manifestations was obtained using a questionnaire applied by community health agents with previous training and capacitation to know about and identify the disease. To analyze correlations, Pearson's correlation coefficient was used with the corresponding statistical significance test. 23,673 individuals were investigated: 323 presented microfilaremia (1.36%) and 741 (3.13%) had clinical complaints that were attributable to LF. Acute dermatolymphangioadenitis (ADLA) was the most prevalent condition (2.2%). Lymphedema, ADLA and chyluria were more commonly reported among female patients. There were positive associations between all the clinical complaints reported and filarial infection. Hydrocele presented the most strongly positive association (r=0.699; p<0.001). The present study showed that there is an association between clinical condition reported and the rate of infection among people living in an area of low endemicity for LF. It contributes data that might provide support for healthcare systems and thus optimize disease management, through incorporating surveillance measures directed towards preventing disability and reducing the psychosocial and economic impact of the disease on poor populations living in areas endemic for LF. PMID:27427218

  9. The palaeoclimatic significance of Eurasian Giant Salamanders (Cryptobranchidae: Zaissanurus, Andrias) - indications for elevated humidity in Central Asia during global warm periods (Eocene, late Oligocene warming, Miocene Climate Optimum)

    NASA Astrophysics Data System (ADS)

    Vasilyan, Davit; Böhme, Madelaine; Winklhofer, Michael

    2010-05-01

    Cryptobranchids represent a group of large sized (up to 1.8 m) tailed amphibians known since the Middle Jurassic (Gao & Shubin 2003). Two species are living today in eastern Eurasia: Andrias davidianus (China) and A. japonicus (Japan). Cenozoic Eurasian fossil giant salamanders are known with two genera and two or three species from over 30 localities, ranging from the Late Eocene to the Early Pliocene (Böhme & Ilg 2003). The Late Eocene species Zaissanurus beliajevae is restricted to the Central Asian Zaissan Basin (SE-Kazakhstan, 50°N, 85°E), whereas the Late Oligocene to Early Pliocene species Andrias scheuchzeri is distributed from Central Europe to the Zaissan Basin. In the latter basin the species occur during two periods; the latest Oligocene and the late Early to early Middle Miocene (Chkhikvadse 1982). Andrias scheuchzeri is osteological indistinguishable from both recent species, indicating a similar ecology (Westfahl 1958). To investigate the palaeoclimatic significance of giant salamanders we analyzed the climate within the present-day distribution area and at selected fossil localities with independent palaeoclimate record. Our results indicate that fossil and recent Andrias species occur in humid areas where the mean annual precipitation reach over 900 mm (900 - 1.300 mm). As a working hypothesis (assuming a similar ecology of Andrias and Zaissanurus) we interpret occurrences of both fossil Eurasian giant salamanders as indicative for humid palaeoclimatic conditions. Based on this assumption the Late Eocene, the latest Oligocene (late Oligocene warming) and the late Early to early Middle Miocene (Miocene Climatic Optimum) of Central Asia (Zaissan Basin) are periods of elevated humidity, suggesting a direct (positive) relationship between global climate and Central Asian humidity evolution. Böhme M., Ilg A. 2003: fosFARbase, www.wahre-staerke.com/ Chkhikvadze V.M. 1982. On the finding of fossil Cryptobranchidae in the USSR and Mongolia. Vertebrata

  10. Assessing numbers and faces: a prerequisite for improving access to lymphatic filariasis morbidity care.

    PubMed

    Becker, Sören L; Fürst, Thomas; Addiss, David G; Utzinger, Jürg

    2015-06-01

    Concerted efforts to eliminate lymphatic filariasis worldwide have registered success; multiple rounds of mass drug administration have led to the interruption of transmission in many previously endemic areas. However, the management of patients with established clinical disease (e.g., lymphoedema, hydrocoele and acute dermatolymphangioadenitis) has not been addressed sufficiently. Two recent studies from Malawi underscore the need for accurate epidemiological and clinical data, and comprehensive morbidity assessments across various domains of daily life. Addressing these issues will guide the implementation of programmes to improve access to treatment and disability prevention for affected individuals in Malawi and beyond. PMID:25778735

  11. Sexual Functioning Morbidity Among Cancer Survivors: Current Status and Future Research Directions

    PubMed Central

    ANDERSEN, BARBARA L.

    2009-01-01

    The current article reviews available data and considers methodologic issues for future research in which sexual functioning among adult cancer patients is an endpoint variable. Circumstances that may cause sexual disruption for any cancer patient are suggested, including mood disturbance, changed health status, somatization, and reprioritization of life concerns. Data on the incidence and magnitude of sexual functioning morbidity following the diagnosis and treatment of cancer at major organ sites, including breast, genital, colon, rectum, and bladder, are reviewed. Finally, strategies for continuing descriptive study of the sexual problems of cancer patients are suggested. Such data are necessary to eventually target preventive or therapeutic resources to patients in greatest need. PMID:3978569

  12. [THE MORBIDITY OF POPULATION OF THE RUSSIAN FEDERATION: GEOGRAPHIC CHARACTERISTICS].

    PubMed

    Semenov, V Yu

    2015-01-01

    The article considers the results of analysis of characteristics of morbidity of population residing in various geographic conditions of the Russian Federation. The comparison was applied to morbidity of residents of subjects of the Russian Federation residing approximately at the levels of 50 and 60 of northern longitude according data of 2008-2013. The average annual size of population of the Northern territories amounted to 8,994,112 and in the southern territories 32,600,569. The maximal differences are noted in relation to diseases of respiratory organs and congenital abnormalities of blood circulation system. Actually, indicators of morbidity of diseases of cardiovascular system and ischemic heart diseases had no differences. The rest of analyzed indicators differed on 10-40% towards higher values in the Northern regions. The exception included cerebrovascular diseases with morbidity higher in southern territories up to 11% than in northern territories. PMID:27116829

  13. Understanding levels of morbidity and hospitalization in Kerala, India.

    PubMed Central

    Dilip, T. R.

    2002-01-01

    The prevalence of ailments and hospitalization in Kerala was examined using data from the 52 nd National Sample Survey Data on Health Care in Kerala in 1995-6. The survey included 24401 people from 4928 households. Age and seasonality had considerable effects on the morbidity of individuals. The burden of ill health was higher in rural areas than in urban areas. People who were more likely to have a better lifestyle had a higher level of morbidity and hospitalization. Regional differences were seen, with levels of morbidity and hospitalization higher in the comparatively developed regions of Southern Kerala than in Northern Kerala. Factors like physical accessibility of health care services and capacity to seek health care services could create artificial differences in morbidity and hospitalization among different subgroups of the population in Kerala. PMID:12378294

  14. Metabolic dysfunction in lymphocytes promotes postoperative morbidity.

    PubMed

    Edwards, Mark R; Sultan, Pervez; del Arroyo, Ana Gutierrez; Whittle, John; Karmali, Shamir N; Moonesinghe, S Ramani; Haddad, Fares S; Mythen, Michael G; Singer, Mervyn; Ackland, Gareth L

    2015-09-01

    Perioperative lymphopenia has been linked with an increased risk of postoperative infectious complications, but the mechanisms remain unclear. We tested the hypothesis that bioenergetic dysfunction is an important mechanism underlying lymphopenia, impaired functionality and infectious complications. In two cohorts of patients (61-82 years old) undergoing orthopaedic joint replacement (n=417 and 328, respectively), we confirmed prospectively that preoperative lymphopenia (≤1.3 x 10(9)·l(-1); <20% white cell count; prevalence 15-18%) was associated with infectious complications (relative risk 1.5 (95% confidence interval 1.1-2.0); P=0.008) and prolonged hospital stay. Lymphocyte respirometry, mitochondrial bioenergetics and function were assessed (n=93 patients). Postoperative lymphocytes showed a median 43% fall (range: 26-65%; P=0.029; n=13 patients) in spare respiratory capacity, the extra capacity available to produce energy in response to stress. This was accompanied by reduced glycolytic capacity. A similar hypometabolic phenotype was observed in lymphocytes sampled preoperatively from chronically lymphopenic patients (n=21). This hypometabolic phenotype was associated with functional lymphocyte impairment including reduced T-cell proliferation, lower intracellular cytokine production and excess apoptosis induced by a range of common stressors. Glucocorticoids, which are ubiquitously elevated for a prolonged period postoperatively, generated increased levels of mitochondrial reactive oxygen species, activated caspase-1 and mature interleukin (IL)-1β in human lymphocytes, suggesting inflammasome activation. mRNA transcription of the NLRP1 inflammasome was increased in lymphocytes postoperatively. Genetic ablation of the murine NLRP3 inflammasome failed to prevent glucocorticoid-induced lymphocyte apoptosis and caspase-1 activity, but increased NLRP1 protein expression. Our findings suggest that the hypometabolic phenotype observed in chronically lymphopenic

  15. Mesenchymal stem/stromal cells-a key mediator for regeneration after perinatal morbidity?

    PubMed

    Mueller, Martin; Wolfs, Tim G A; Schoeberlein, Andreina; Gavilanes, Antonio W D; Surbek, Daniel; Kramer, Boris W

    2016-12-01

    Perinatal complications in both term- and preterm-born infants are a leading cause of neonatal morbidities and mortality. Infants face different challenges in the neonatal intensive care unit with long-term morbidities such as perinatal brain injury and bronchopulmonary dysplasia being particularly devastating. While advances in perinatal medicine have improved our understanding of the pathogenesis, effective therapies to prevent and/or reduce the severity of these disorders are still lacking. The potential of mesenchymal stem/stromal cell (MSC) therapy has emerged during the last two decades, and an increasing effort is conducted to address brain- and lung-related morbidities in neonates at risk. Various studies support the notion that MSCs have protective effects. MSCs are an easy source and may be readily available after birth in a clinical setting. MSCs' mechanisms of action are diverse, including migration and homing, release of growth factors and immunomodulation, and the potential to replace injured cells. Here, we review the pathophysiology of perinatally acquired brain and lung injuries and focus on MSCs as potential candidates for therapeutic strategies summarizing preclinical and clinical evidence. PMID:26869264

  16. Discriminability of personality profiles in isolated and Co-morbid marijuana and nicotine users.

    PubMed

    Ketcherside, Ariel; Jeon-Slaughter, Haekyung; Baine, Jessica L; Filbey, Francesca M

    2016-04-30

    Specific personality traits have been linked with substance use disorders (SUDs), genetic mechanisms, and brain systems. Thus, determining the specificity of personality traits to types of SUD can advance the field towards defining SUD endophenotypes as well as understanding the brain systems involved for the development of novel treatments. Disentangling these factors is particularly important in highly co morbid SUDs, such as marijuana and nicotine use, so treatment can occur effectively for both. This study evaluated personality traits that distinguish isolated and co-morbid use of marijuana and nicotine. To that end, we collected the NEO Five Factor Inventory in participants who used marijuana-only (n=59), nicotine-only (n=27), both marijuana and nicotine (n=28), and in non-using controls (n=28). We used factor analyses to identify personality profiles, which are linear combinations of the five NEO Factors. We then conducted Receiver Operating Characteristics (ROC) curve analysis to test accuracy of the personality factors in discriminating isolated and co-morbid marijuana and nicotine users from each other. ROC curve analysis distinguished the four groups based on their NEO personality patterns. Results showed that NEO Factor 2 (openness, extraversion, agreeableness) discriminated marijuana and marijuana+nicotine users from controls and nicotine-only users with high predictability. Additional ANOVA results showed that the openness dimension discriminated marijuana users from nicotine users. These findings suggest that personality dimensions distinguish marijuana users from nicotine users and should be considered in prevention strategies. PMID:27086256

  17. Atherosclerotic process in taxi drivers occupationally exposed to air pollution and co-morbidities.

    PubMed

    Brucker, Natália; Charão, Mariele F; Moro, Angela M; Ferrari, Pedro; Bubols, Guilherme; Sauer, Elisa; Fracasso, Rafael; Durgante, Juliano; Thiesen, Flávia V; Duarte, Marta M; Gioda, Adriana; Castro, Iran; Saldiva, Paulo H; Garcia, Solange C

    2014-05-01

    Consistent evidence has indicated that the exposure to environmental air pollution increases the risk of cardiovascular disease. This study aimed to evaluate the possible effects of occupational exposure to air pollution, especially to polycyclic aromatic hydrocarbons (PAHs), and the influence of co-morbidities on the atherosclerotic process and inflammation. For that, biomarkers of exposure such as 1-hydroxypyrene urinary, oxidative damage and markers of cardiovascular risk were determined in plasma, serum and blood. In addition, inflammation models such as carotid intima-media thickness and serum inflammatory cytokines were analyzed in 58 taxi drivers with and without co-morbidity. The results demonstrated that considering only taxi drivers without co-morbidities, 15% presented carotid intima-media thickness above reference values. For the first time it has been demonstrated that urinary 1-hydroxypyrene levels were associated with carotid intima-media thickness and with serum homocysteine levels. The multiple linear regression analysis showed that several factors may contribute to the increased carotid intima-media thickness, among which age, interleukin-6, fibrinogen and exposure to PAHs stand out. In summary, our results suggest that chronic occupational exposure to atmospheric pollution could be an additional contributor to the atherogenesis process, leading to impaired vascular health. Moreover, carotid intima-media thickness, serum homocysteine levels, fibrinogen and the total cholesterol/HDL-c ratio could be suggested as preventive measures to monitor drivers' health. PMID:24637182

  18. Standardized severe maternal morbidity review: rationale and process.

    PubMed

    Kilpatrick, Sarah J; Berg, Cynthia; Bernstein, Peter; Bingham, Debra; Delgado, Ana; Callaghan, William M; Harris, Karen; Lanni, Susan; Mahoney, Jeanne; Main, Elliot; Nacht, Amy; Schellpfeffer, Michael; Westover, Thomas; Harper, Margaret

    2014-08-01

    Severe maternal morbidity and mortality have been rising in the United States. To begin a national effort to reduce morbidity, a specific call to identify all pregnant and postpartum women experiencing admission to an intensive care unit or receipt of 4 or more units of blood for routine review has been made. While advocating for review of these cases, no specific guidance for the review process was provided. Therefore, the aim of this expert opinion is to present guidelines for a standardized severe maternal morbidity interdisciplinary review process to identify systems, professional, and facility factors that can be ameliorated, with the overall goal of improving institutional obstetric safety and reducing severe morbidity and mortality among pregnant and recently pregnant women. This opinion was developed by a multidisciplinary working group that included general obstetrician-gynecologists, maternal-fetal medicine subspecialists, certified nurse-midwives, and registered nurses all with experience in maternal mortality reviews. A process for standardized review of severe maternal morbidity addressing committee organization, review process, medical record abstraction and assessment, review culture, data management, review timing, and review confidentiality is presented. Reference is made to a sample severe maternal morbidity abstraction and assessment form. PMID:25004341