Alexander, I C; Brown, R C; Jubb, G A; Pickering, P; Hoskins, J A
In vitro solubility testing is an important means of assessing the likely behavior of fibers that are respired and accumulate in the lung. The problem has been that such tests often do not mirror the dissolution and removal mechanisms seen in vivo. Comparison of iron and silica solubility values of various types of mineral fiber showed no obvious correlation. Treating a mineral fiber containing high levels of calcium with normal balanced salt solutions produces a precipitate of calcium phosphate on the fiber surface. This deposit was not seen in fibers isolated from the lung of exposed animals. New solutions have been developed and with variations in the methods of exposing fibers, results similar to those seen in vivo have been obtained. Suitable fluid phases have been examined in static and flow-through systems. The relationship of solubility to biological activity is discussed. Images Figure 3. Figure 3. Figure 3. Figure 3. Figure 4. Figure 4. Figure 4. Figure 4. Figure 5. Figure 5. Figure 5. Figure 5. Figure 6. Figure 6. Figure 6. Figure 6. PMID:7882958
Within the pediatric population of their practices, family physicians frequently encounter infants with skin rashes. This article discusses several of the more common rashes of infancy: atopic dermatitis, cradle cap, diaper dermatitis and miliaria. Etiology, clinical picture and possible approaches to treatment are presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:21267297
The esophagus may be involved directly or indirectly by numerous disease conditions. On occasion, the esophageal process may be the key to the diagnosis. In some situations, the esophageal manifestation of a disease may be more immediately life-threatening than the primary process. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:7310903
Martin, Donald C.; Kaufman, Joseph J.
Hydronephrosis may be acute, recurrent and related to ingestion of fluid. Frequently a lower polar vessel is an etiological factor. The condition is amenable to corrective operation by a variety of surgical techniques, as in the six cases here reported. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:14154288
Robson, Wm. Lane M.; Leung, Alexander K.C.; Boag, Graham S.
The clinical and radiological presentations of 12 pediatric urological disorders are described. The described disorders include pyelonephritis, vesicoureteral reflux, ureteropelvic obstruction, ureterovesical obstruction, ectopic ureterocele, posterior urethral valves, multicystic dysplastic kidney, polycystic kidney disease, ectopic kidney, staghorn calculi, urethral diverticulum, and urethral meatal stenosis. ImagesFigure 1-2Figure 3Figure 3Figure 4Figure 5Figure 6-7Figure 8-9Figure 10Figure 11-12 PMID:21229068
Henshel, D S; Martin, J W; DeWitt, J C
Previous studies have indicated that in ovo exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds is correlated with the development of grossly asymmetric brains. This asymmetry is manifested as a difference between the two halves of the forebrain and the tecta. Previously, only wildlife species (heron, cormorant, and eagle) had been shown to manifest this response. In the wildlife studies, the frequency and degree of left-right interhemispheric differences had been correlated with the levels of polychlorinated dibenzo-p-dioxin toxic equivalency factors (TEFs) in eggs from the same nest (heron, cormorant). We studied the effect of in ovo exposure to TCDD on the brain throughout development in a sensitive laboratory model (chicken). Embryos from chicken eggs (Gallus gallus) injected with one of several doses of TCDD or vehicle control were sacrificed after 9, 11, 13, 15, 17, or 20 days of incubation, or incubated to hatch and then sacrificed either within 24 hr or at 3 weeks post-hatch. Measurements of both chicken embryo and hatchling brains indicated that 1) TCDD alone induced the brain asymmetry in developing chickens; 2) this brain asymmetry was similar to that observed in animals exposed in the wild to a mixture of TCDD-related contaminants; 3) there was a dose-related increase in both the frequency and severity of brain asymmetry observed at all ages measured; and 4) the asymmetry was measurable in embryonic brains at an age when the braincase was a thin, flexible layer (embryonic day 9), implying that the effect of TCDD was directly on the developing brain and not indirectly via an effect on the braincase. Images Figure 1. Figure 2. Figure 2. Figure 2. Figure 2. Figure 2. Figure 2. Figure 3. Figure 3. Figure 3. Figure 3. Figure 3. Figure 3. Figure 4. Figure 4. Figure 4. Figure 4. Figure 4. Figure 4. Figure 5. Figure 5. Figure 5. Figure 5. Figure 5. Figure 5. Figure 6. A Figure 6. B Figure 6. C Figure 6. D Figure 7. PMID:9294718
Kohorn, E. I.
The persons who directed the academic teaching of women's health at Yale Medical School are presented by biographical sketches recounting their achievements and some of the difficulties they encountered. Three who provided particular catalysis were Nathan Smith, Herbert Thoms, and Lee Buxton. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 PMID:8303913
Horn, Karl L.; Hankinson, Hal L.; Nissen, Alan J.; McDaniel, Shawna L.
We present two patients with primary petrous apex schwannoma. These tumors were centered on the petrous carotid artery and are thought to have originated from the deep petrosal nerve. This would account for the paucity of neurologic deficits in these patients. Imaging findings and surgical treatment of primary petrous apex schwannomas are discussed. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8 PMID:17170967
Miedzinski, Lil J.
Early clinical signs and symptoms of human immunodeficiency virus infection are protean and can reflect the effects of the virus or represent early manifestations of an illness associated with the acquired immunodeficiency syndrome. Knowledge of a patient's potential risk for HIV infection and of the natural history of the illness allow early signs and symptoms to be recognized. Early intervention can delay progression to AIDS. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21221397
Elston, T C; Oster, G
The bacterial flagellar motor is driven by a flux of ions between the cytoplasm and the periplasmic lumen. Here we show how an electrostatic mechanism can convert this ion flux into a rotary torque. We demonstrate that, with reasonable parameters, the model can reproduce many of the experimental measurements. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 11 FIGURE 14 FIGURE 15 p720-a PMID:9251788
Kumar, P. Pradeep; Good, Roger R.; Jones, Ernest O.; Somers, James E.; McAnulty, Bruce E.; McCaul, Gayle F.; Rogers, Sally S.; Reeves, Michael A.; Sanders, Cheryl K.
Extended-field therapeutic irradiation is the treatment of choice for the majority of patients diagnosed with pathologic stages I and II Hodgkin's disease, and total nodal irradiation can be effectively used to treat selected stage III Hodgkin's patients. Standard 100-cm source-to-axis distance extended-field isocentric technique and results are presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:3312619
Niazi, Wasim; Boggan, James E.
An unusual case of schwannoma arising from the third cranial nerve in a thirteen year old male is reported. The patient presented with paresis of the right oculomotor nerve and ipsilateral hemiparesis. The clinical features of this case are discussed and the pertinent medical literature reviewed. ImagesFigure 1p220-bFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:17171175
Erickson, Bradley J.; Robb, Richard A.
While great advances have been made in developing new and better ways to produce medical images, the technology to efficiently display and analyze them has lagged. This paper describes design considerations and development of a workstation based on an IBM PC/AT for the analysis of three and four dimensional medical image data. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9
Brant-Zawadzki, Michael; Norman, David; Newton, T. Hans; Kucharczyk, Walter
Magnetic resonance imaging has developed rapidly and now has superior ability to detect and to characterize disease in the central nervous system without any significant biologic hazard. It is becoming the screening method of choice in the diagnosis of neoplasm, ischemia, hemorrhage, infection and degenerative and demyelinating diseases involving the central nervous system. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9. PMID:3976220
Shabo, A L; Maxwell, D S; Kreiger, A E; Straatsma, B R
There are important similarities between human and experimental monkey rubeosis iridis. We believe that we have developed a useful primate model to study iris neovascularization and that the possible role of immunity to insulin in the pathogenesis of human diabetic rubeosis iridis warrants further detailed consideration. Images FIGURE 8 FIGURE 1. 1 FIGURE 1. 2 FIGURE 1. 3 FIGURE 1. 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 9 FIGURE 10 PMID:405785
Schabert, F A; Engel, A
Crystalline membranes reconstituted from Escherichia coli OmpF porin and phospholipids were adsorbed to freshly cleaved mica and imaged in solution by the atomic force microscope. The extracellular as well as the periplasmic side of the porin trimers could be identified and the conditions to record topographs at 1-nm lateral and 0.1-nm vertical resolution were established. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 PMID:7696479
Oji, E. O.
The stems of corn, millet, sugar cane and the banana leaf frond excite some clinical and pathological effects in the rabbit's eye when implanted either into the anterior chamber (AC) or subconjunctivally. These effects have not been sight threatening. The materials can either be left to be cleared by the body's phagocytes when they produce mild inflammatory reaction or removed surgically if the inflammatory response is moderate when fragments have been left intraocularly. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:2221773
Nimmo-Wilkie, Judith S.; Radostits, O. M.
This case of fusobacteremia appears to be identical to an interesting and unusual syndrome previously reported. We wish to bring the syndrome to the attention of others who may be able to elucidate the etiology further. Because hematological examinations are frequently not done on calves, this condition may be more common than reports suggest. Perhaps others who observe this syndrome in calves may be able to investigate the role of other agents such as viruses or mycotoxins. Experimental work may be able to establish whether or not the exotoxins of Fusobacterium necrophorum can suppress granulopoiesis. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:7248893
Alexander, George A.
Cancer is an important cause of morbidity and mortality in Tanzania. According to the Tanzanian Cancer Registry, which records all histologically confirmed malignant tumors, the number of reported cancer cases has increased significantly over the past three decades. The most commonly diagnosed tumors are cervix cancer, skin cancer, primary liver cancer, Kaposi's sarcoma, and Burkitt's lymphoma. Geographical and tribal variations exist in disease frequency. Environmental factors appear to have a major role in the distribution. Through elimination of these factors, cancer in Tanzania could be reduced if not totally prevented. ImagesFigure 3Figure 4Figure 5Figure 6Figure 7Figure 8 PMID:6631988
Bywaters, E G L
Erosion and inflammatory changes in the carpus, fingers and toes of a rhesus monkey, Macaca mulatta, are described; this was one of 152 animals in each of which four fixed limbs were available for examination. The histological changes resembled closely those found in adult human rheumatoid arthritis. The limited literature is reviewed (including cases with amyloid disease). ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10.Figure 11.Figure 12. PMID:7299780
Astier, C; Labbé, J P; Roustan, C; Benyamin, Y
In myofibrils, titin (also called connectin) molecules span from Z line to M line and constitute a third filament system containing an elastic domain in the I band. This giant protein is particularly sensitive to proteolysis in situ. Treatment of rabbit skeletal myofibrils with exogenous proteinases induces a release of titin fragments, which are detected in the soluble myofibrillar fraction. The cleavage of titin occurs at specific points localized at the proximity of Z line and could lead to a concomitant release of alpha-actinin. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8457201
Sharnoff, Mark; Brehm, Lawrence P.; Henry, Richard W.
The principles of microdifferential holography are developed primarily from nonmathematical argument, and the method's capabilities are compared with those of x-ray and optical diffraction. Microdifferential holography is very sensitive to small displacements of strongly scattering elements of a specimen whether or not they can be optically resolved. We present and interpret differential images of electrical activity of neurons and of contractile activity of isolated skeletal fibers. The latter confirm the suggestion of earlier work that the dynamic regions of contracting muscle are organized along myofibrillar segments rather than by sarcomeres. ImagesFIGURE 2FIGURE 3FIGURE 4FIGURE 5FIGURE 6FIGURE 7 PMID:19431634
Beiske, K.; Ruud, E.; Drack, A.; Marton, P. F.; Godal, T.
In vitro stimulation of cells from 8 non-Hodgkin's lymphomas comprising several histologic types with a tumor promotor (TPA) and with or without anti-immunoglobulins directed against the surface immunoglobulin of the tumor cells is reported. Morphologic transformation to immunoblastic and plasmablastic cells, but not to plasma cells, and induction of Ig and DNA synthesis were observed. A comparative analysis, including flow cytofluorometry, light microscopy combined with immunocytochemistry, and electron microscopy, suggests that the three events may not always be associated phenomena at the single-cell level even in monoclonal cell populations. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6375389
Smedema, J.P.; Zondervan, P.E.; van Hagen, P.; ten Cate, F.J.; Bresser, P.; Doubell, A.F.; Pattynama, P.; Hoogsteden, H.C.; Balk, A.H.M.M.
Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of cardiac sarcoidosis, and give a brief review on the current management of this condition. Magnetic Resonance Imaging (MRI) can be of great help in diagnosing this condition as well as in the follow-up of the response to therapy. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:25696121
Gil-Salú, José L.; Lázaro, Rafael; Aldasoro, José; Gonzalez-Darder, José M.
Synovial chondromatosis are rare entities but are well-described lesions in the literature that can affect many joint areas of the body. A case of tumoral synovial chondromatosis involving the temporomandibular joint with intracranial extension through mandibular fossa is reported. As long as there was significant infratemporal and extradural invasion of the middle and posterior fossa, a transtemporal and infratemporal approach was performed and total removal of the lesions was achieved. A brief review of skull base synovial chondromatosis is presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11 PMID:17171059
Kirsch, Wolff M.; Zhu, Yong Hua; Hardesty, Robert A.; Petti, George; Furnas, David
Reconstructive challenges engendered by skull base surgery are critical determinants of outcome. A novel nonpenetrating, arcuate-legged clip has proven to be both technically and biologically effective for management of these difficult closures. Clips have facilitated reconstructions associated with the surgical management of eight skull base cases: leiomyosarcoma of the orbit, middle fossa, ptyergopalatine fossa, two meningiomas (petrotentorial, cavernous sinus), vagus nerve paraganglioma, complex traumatic orbital dural tear, and one basilar and two vertebral artery aneurysms. ImagesFigure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 12Figure 14Figure 16Figure 17Figure 18 PMID:17170909
Gottlieb, Leon S.; Boylen, Thomas C.
Complications resulting from drug abuse more frequently affect the lung than any other organ. The spectrum of pulmonary complications associated with drug abuse is wide. The current practice of using mixtures of drugs is mainly responsible for the increase in pulmonary complications. The chief complications observed in a series of 241 drug abuse patients were aspiration pneumonitis (12.9 percent), pulmonary edema (10.0 percent), and pneumonia (7.5 percent). ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10. PMID:4812215
Becker, S. William
Benign melanocytic lesions include lentigo, ephelid (freckle), pigmented nevus, sacral spot, blue nevus, and combined nevus and blue nevus. Malignant melanocytic lesions are melanomas, which arise from melanocytes at the epidermodermal junction, or, rarely, from blue nevi. They usually originate in brown plaques known as lentigo maligna, in pigmented nevi, or in normal skin. Melanoma is diagnosed clinically in less than 50 per cent of instances. Biopsy is therefore of great importance, since practically all melanoma can be cured by adequate early resection. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8. PMID:13511215
Crowe, A.; Ksiezak-Reding, H.; Liu, W. K.; Dickson, D. W.; Yen, S. H.
Antibody (Ab) E-1 was raised to the amino terminus (19 to 33 amino acid residues) of human tau. It recognized Alzheimer's disease proteins A68 (MW 60, 64, 68 kd), labeled paired helical filaments, and had no reactivity with tau from rat, mouse, and bovine brains. The results indicate that the N terminus of tau is incorporated in A68 proteins and paired helical filaments and that human tau proteins contain species-specific amino acid sequences. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1721492
O'Sullivan, G. J.; Ray, S. A.; Lewis, J. S.; Lopez, A. J.; Powell, B. W.; Moss, A. H.; Dormandy, J. A.; Belli, A. M.; Buckenham, T. M.
The management of iatrogenic pseudoaneurysms (IPAs) demands close co-operation between radiologist, vascular surgeon and plastic surgeon. Ideally, each patient should be reviewed employing a team approach. Many IPAs require only observation; those with a volume greater than 6 cm3 will require treatment as spontaneous thrombosis is uncommon. Radiological treatment options include ultrasound guided compression repair (UGCR), embolisation, and covered stenting. Occasionally, these are unsuccessful or contra-indicated, and the vascular surgical approach is discussed in detail. Finally, the role of the plastic surgeon in dealing with skin ischaemia is detailed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:10615187
Cabo, C; Pertsov, A M; Davidenko, J M; Baxter, W T; Gray, R A; Jalife, J
In cardiac tissue, during partial blockade of the membrane sodium channels, or at high frequencies of excitation, inexcitable obstacles with sharp edges may destabilize the propagation of electrical excitation waves, causing the formation of self-sustained vortices and turbulent cardiac electrical activity. The formation of such vortices, which visually resembles vortex shedding in hydrodynamic turbulent flows, was observed in sheep epicardial tissue using voltage-sensitive dyes in combination with video-imaging techniques. Vortex shedding is a potential mechanism leading to the spontaneous initiation of uncontrolled high-frequency excitation of the heart. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 7 PMID:8785270
Harris, Frederick W.; Janzen, Eugene D.
Haemophilus somnus has long been associated with thrombotic meningoencephalomyelitis but has also been identified as the agent responsible for other clinical diseases including respiratory disease, reproductive problems, myocarditis, otitis, conjunctivitis, mastitis, and polyarthritis. Exposure to the bacteria is widespread and infection may occur via the respiratory tract from urogenital excretions and secretions. Diagnosis and treatment of hemophilosis may be easy or difficult depending on the manifestation presented, and special procedures must be taken to facilitate isolation of the organism. Satisfactory control measures are not available; vaccination is the only preventive measure demonstrating a beneficial effect. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:17423440
Bundza, Adam; Finley, Gordon G.; Easton, Kenneth L.
An outbreak of cysticercosis (infestation with the larvae of Taenia saginata) occurred in feedlot cattle in Ontario in 1986. Two hundred and thirty-three of 271 steers were confirmed histologically to be positive for cysticerci. Nineteen (8.2%) animals had viable cysticerci, 87 (37.3%) had degenerated cysticerci, 77 (33.0%) had mineralized cysticerci, and 50 (21.5%) steers had lymphoid granulomas consistent with cysticercosis. Three viable cysticerci were partly evaginated and one degenerate cysticercus was fully evaginated. ImagesFigure 1., Figure 2., Figure 3., Figure 4., Figure 5., Figure 6., Figure 7., Figure 8., Figure 9., F PMID:17423200
Pike, A. C.; Super, M.
Velocardiofacial syndrome is a syndrome of multiple anomalies that include cleft palate, cardiac defects, learning difficulties, speech disorder and characteristic facial features. It has an estimated incidence of 1 in 5000. The majority of cases have a microdeletion of chromosome 22q11.2. The phenotype of this condition shows considerable variation, not all the principal features are present in each case. Identification of the syndrome can be difficult as many of the anomalies are minor and present in the general population. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9497944
Noonan, Charles D.
With meticulous preparation of the patient and with careful technique, the soft tissues of the pelvis are identifiable in most cases. Search should be made for the traces of abnormal pelvic structures on plain-film studies. Once the normal is recognized, any variations are easily identified. The fundamental differences between various radiologic densities—air, fat, fluid, muscle, calcium, bone and metal—should be observed. Special procedures can be used to enhance the contrasts after adequate evaluation of the simplest and, on many occasions, the invaluable, plain-film study of the soft tissues of the pelvis. ImagesFigure 2.Figure 3.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8. PMID:14232160
Shy, Carl M.; Degnan, Darrah; Fox, Donald L.; Mukerjee, Shaibal; Hazucha, Milan J.; Boehlecke, Brian A.; Rothenbacher, Dietrich; Briggs, Patsy M.; Devlin, Robert B.; Wallace, Dennis D.; Stevens, Robert K.; Bromberg, Philip A.
The purpose of the study presented here was to simultaneously measure air quality and respiratory function and symptoms in populations living in the neighborhood of waste incinerators and to estimate the contribution of incinerator emissions to the particulate air mass in these neighborhoods. We studied the residents of three communities having, respectively, a biomedical and a municipal incinerator, and a liquid hazardous waste-burning industrial furnace. We compared results with three matched-comparison communities. We did not detect differences in concentrations of particulate matter among any of the three pairs of study communities. Average fine particulate (PM2.5) concentrations measured for 35 days varied across study communities from 16 to 32 μg/m3. Within the same community, daily concentrations of fine particulates varied by as much as eightfold, from 10 to 80 μg/m3, and were nearly identical within each pair of communities. Direct measurements of air quality and estimates based on a chemical mass balance receptor model showed that incinerator emissions did not have a major or even a modest impact on routinely monitored air pollutants. A one-time baseline descriptive survey (n = 6963) did not reveal consistent community differences in the prevalence of chronic or acute respiratory symptoms between incinerator and comparison communities, nor did we see a difference in baseline lung function tests or in the average peak expiratory flow rate measured over a period of 35 days. Based on this analysis of the first year of our study, we conclude that we have no evidence to reject the null hypothesis of no acute or chronic respiratory effects associated with residence in any of the three incinerator communities. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 4.Figure 4.Figure 5.Figure 5.Figure 5.Figure 6.Figure 7. PMID:7588484
Elective surgery requires planned incisions and incisions require appropriate blades. In the prehistoric era, division of the umbilical cord and other minor procedures were probably undertaken with human teeth and nails, and later with plant, animal and mineral substitutes, as witnessed by studies of primitive societies still surviving or recently extinct. More efficient metallic blades appeared in historic times and ultimately generated five specific shapes which are analysed in detail. Today, as minimally invasive techniques, endoscopes, laser and ultrasound sources evolve, many hallowed incisions of surgical access diminish in length or disappear entirely. In historical terms, elective surgery of the twentieth century will be recalled as an interlude characterised by maximally invasive incisions. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:7486768
Smith, D. R. K.; Leach, D. H.; Bell, R. J.
Anatomical anomalies in the hind feet of a seven month old Appaloosa foal were identified and investigated through the use of gross anatomical dissection, radiography and angiography. Abnormalities were restricted to the distal aspect of both hind legs, the right hind leg being more severely affected. Anatomically the right foot resembled that of an equine fetus of approximately 120 days gestational age. Disruption of vascular perfusion to hoof structures was evident in both hind legs and was related to areas of abnormal bone conformation as well as to areas of abnormal ossification and calcification. Phalangeal and navicular bone hypoplasia were apparent as were soft tissue and joint anomalies. Although the etiology of the defects identified remains obscure, several theories are suggested, namely heritability, acquired defects and the possible teratogenic effects of clenbuterol. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10. PMID:17422612
Fringeli, U P
A new phase transition of L-alpha-dipalmitoyl phosphatidylcholine (DPPC) monohydrate from the "biaxial" phase to a crystalline phase (C phase) has been found at 71 degrees C by means of infrared attenuated total reflection (IR-ATR) spectroscopy. The transition is characterized by drastic conformational changes in the glycerophosphorylcholine moiety, which led on the one hand to an alignment of the turn near the ester group in the hydrocarbon chain at glycerol C(2) position. On the other hand a uniform conformation of the glycerophosphorylcholine moiety is found to be typical for the C phase, in contrast to nonuniform head group conformations of DPPC in other regions of the DPPC/water phase diagram investigated so far. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 8 PMID:6894555
Devaud, G; Furcinitti, P S; Fleming, J C; Lyon, M K; Douglas, K
We have examined the structure of S-layers isolated from Sulfolobus acidocaldarius using atomic force microscopy (AFM) and transmission electron microscopy (TEM). From the AFM images, we were able to directly observe individual dimers of the crystal, defects in the crystal structure, and twin boundaries. We have identified two types of boundaries, one defined by a mirror plane and the other by a glide plane. This work shows that twin boundaries are highly structured regions that are directly related to the organization of units within each crystal domain. Projection maps from TEM images have shown that there are significant differences in the final average maps has allowed us to relate high magnification views obtained by AFM to the relatively high resolution information obtained by electron microscopy and image processing. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:1420904
Hemrend, Bernard; Altuna, Gurkan; Tompson, Bryan
The authors of this article offer an introduction to the field of orthodontics. They present the latest advances in orthodontic appliances and some of the possible consequences of orthodontic treatment. They discuss a number of cases and offer examples of some of the more common problems that the orthodontist is asked to treat. Such cases include severe Class II, division 1 malocclusion, surgical orthodontics, “long-face” syndrome, adult orthodontics-TMJ-periodontics, late adult growth, and post-retention changes. Practical information useful to the physician who encounters patient with these disorders is balanced with good research data to support the various claims. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9 PMID:21249042
Lin, F R; Hsu, H S; Mumaw, V R; Moncure, C W
A procedure was developed with which peritoneal exudate cell (PEC) preparations were fixed in a glutaraldehyde-picric acid mixture, post-fixed with osmium tetroxide, embedded in LR White resin and then stained with immunogold probe. It provided tissue sections showing both well-defined ultrastructures as well as specifically labelled Salmonella O antigens by electron microscopy. Inbred, male C57BL/6 mice were injected intraperitoneally with 2 x 10(7) virulent Salmonella typhimurium. Peritoneal exudate cells were harvested at 16 and 20 hr after infection. Disintegrating intracellular bacteria were identified as salmonellae by the immunogold markers. Deposition of gold particles in the cytoplasm of phagocytes also indicated that intracellular debris contained digested pathogen. This investigation therefore confirms previous findings of the destruction of salmonellae within inflammatory polymorphs and macrophages. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:2668159
Swain, Elisabeth; Li, Chun Ping; Poulton, Jonathan E.
In black cherry (Prunus serotina Ehrh.) homogenates, (R)-amygdalin is catabolized to HCN, benzaldehyde, and d-glucose by the sequential action of amygdalin hydrolase, prunasin hydrolase, and mandelonitrile lyase. The tissue and subcellular localizations of these enzymes were determined within intact black cherry seeds by direct enzyme analysis, immunoblotting, and colloidal gold immunocytochemical techniques. Taken together, these procedures showed that the two β-glucosidases are restricted to protein bodies of the procambium, which ramifies throughout the cotyledons. Although amygdalin hydrolase occurred within the majority of procambial cells, prunasin hydrolase was confined to the peripheral layers of this meristematic tissue. Highest levels of mandelonitrile lyase were observed in the protein bodies of the cotyledonary parenchyma cells, with lesser amounts in the procambial cell protein bodies. The residual endosperm tissue had insignificant levels of amygdalin hydrolase, prunasin hydrolase, and mandelonitrile lyase. Images Figure 5 Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 PMID:16652960
Hackney, R G; Varley, G; Stevens, D; Green, A
The Isle of Man Tourist Trophy motorcycle races remain one of the most popular venues for motorcycle races. This is despite the reduced status of the event. The reason for the loss of world championship and formula one status is the nature of the road racing circuit itself. The twisting narrow roads are only closed to the public at certain times during the practice and race weeks. Motorcycling visitors to the event attempt to emulate their heroes on machines capable of high speeds. Casualties from both visitors and racers are dealt with efficiently by an expanded medical service. This includes the use of an aeromedical evacuation helicopter. Casualties from the visitors exceeded those from the racers themselves during the period reported. Images Figure 1 Figure 2 Figure 4 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8457818
Barth, Albert D.
The knobbed acrosome defect was found at levels of 25 to 100 percent of spermatozoa from 16 of 2054 beef bulls. The incidence of this defect appeared to be particularly high in the Charolais breed. Pedigree analysis of some of the affected Charolais bulls indicated there may be a genetic predisposition for this sperm defect. In eosin-nigrosin stained semen smears the most common form of the abnormality was a flattened or indented apex of the sperm head. A refractile bead at the apex of the sperm head was seen less commonly. Electron microscopy of the spermatozoa from one bull showed that the abnormality was similar to the knobbed sperm defect previously described in Friesian bulls. A breeding trial confirmed that bulls producing spermatozoa with a high incidence of knobbed acrosomes are infertile. ImagesFigure 2 and 3.Figure 4.Figure 5.Figure 6 and 7.Figure 8.Figure 9.Figure 10. PMID:17422706
Nassif, Paul S.; Hankinson, Hal L.; Horn, Karl L.
Surgical access to lesions of the temporal bone anterior to the internal auditory canal and medial to the petrous carotid artery has concerned surgeons for nearly a century. A variety of approaches have been developed to gain access to this region. We report our experience with the middle fossa transpetrous approach for the treatment of a variety of petroclival and/or prepontine lesions. Tentorial transection and the retrolabyrinthine approach to extend this technique is also discussed. In properly selected cases, the middle fossa transpetrous approach is successful in maintaining hearing, labyrinthine and facial function without compromising surgical exposure. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11 PMID:17171001
Chester, J. F.; Ross, J. S.; Malt, R. A.; Weitzman, S. A.
Colonic inflammation was produced in rats and mice by peptides chemotactic for polymorphonuclear leukocytes. Instillation of formylmethionyl-leucyl-phenylalanine (FMLP) and formylnorleucyl-leucyl-phenylalanine (FNLP) into isolated segments of rat colon caused marked mucosal edema and polymorphonuclear leukocyte infiltration within 2 hours. Higher concentrations of FNLP caused ulceration and necrosis as well. Formylmethionine (FMet), a compound with less chemotactic activity, caused much less inflammation. In mice, rectal instillation of FNLP caused dose-dependent acute mucosal inflammation which persisted for longer than 12 hours. Twice-weekly rectal instillation of FNLP provided a model of colitis based on neutrophil chemotaxis. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:4061566
Cottier, H.; Turk, J.; Sobin, L.
This Memorandum proposes a standardized system of reporting the histology of human lymph nodes based on commonly used simple staining techniques. The purpose is to provide a uniform, internationally acceptable system by which the histological structure of lymph nodes can be correlated with other parameters of immunological status. The proposed protocols are intended to provide information that is not available in conventional written reports, that use such terms as “hyperplasia” or “nonspecific lymphadenitis”. ImagesFigure 22Figure 13Figure 5Figure 4Figure 3Figure 14Figure 15Figure 9Figure 21Figure 8Figure 12Figure 17Figure 16Figure 2Figure 7Figure 6Figure 20Figure 19Figure 11Figure 10Figure 18 PMID:4539822
Steven, F. S.; Hill, R. J.
Exposure to the fibrous mineral erionite is known to induce mesothelioma in man and laboratory animals. Previous studies demonstrated the presence of a trypsin-like protease associated with tumour cells. This protease could be demonstrated by the use of fluorescent probes which located cells possessing this enzyme. We have employed this fluorescent probe technique to follow the early events in the lungs of rats exposed to erionite. The evidence presented shows that the mesothelial cells initially lack this enzyme but the enzyme can be detected within hours of exposure of the rat to erionite. The number of mesothelial cells possessing the enzyme steadily increased after a single exposure to the mineral until the animal finally died with a massive pleural tumour. This is the first study of such fluorescent probes in the early stages of tumour induction. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:2851310
Jones, Nanelle Lavina; Molnar, Eva T.; Knasel, Anne L.
Music is a convenient way of bypassing barriers of communication and eliciting responses that may be helpful in the diagnoses and treatment of illness. The use of background music in elevators, in doctors' offices, and in stores are good examples of how music can be used to affect the subconscious mind. In this pilot study drums were used to better define the effects of particular elements of music and sound. When repetitive rhythms are presented as background music to a group of severely developmentally delayed children, three out of four subjects show a definite change in level of development in the unstructured task of free drawing. To discover more about the effects of the various elements of music and to better identify patterns in the environment that are conducive to optimal functioning, further studies are indicated. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8 PMID:2468780
Nation, P. Nick; Williams, Elisabeth S.
Based upon what is known about the habits of common carrion eaters in Alberta, we review the patterns of postmortem scavenging of carcasses of cattle. We then compare with these patterns those reported in the lay press and by veterinarians investigating cattle mutilations in Alberta. We conclude that the so-called “mutilation” of cattle in Alberta was due to scavenging of carcasses and further conclude that claims of human involvement in such incidents require, as a first condition, that postmortem scavenging of the carcass be excluded. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10.Figure 11. PMID:17423422
Stefansson, K.; Wollmann, R.; Jerkovic, M.
In soft tissues outside the central nervous system, S-100 protein is found normally only in Schwann cells. Using the peroxidase-antiperoxidase immunohistochemical method S-100 was also found in tumors derived from Schwann cells and melanocytes, including neurofibromas, neurilemomas, granular cell myoblastomas, cutaneous nevi, and malignant melanomas. S-100 was not detected in malignant Schwannomas, neuroblastomas, oat cell carcinomas, medullary carcinomas of the thyroid, paragangliomas, or meningiomas. S-100 was also absent from neoplasms of soft tissues not usually considered to arise from cells of neural crest origin. S-100 appears to be a useful marker for identifying neoplasms derived from Schwann cells and melanocytes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6278936
Radzun, H. J.; Parwaresch, M. R.; Feller, A. C.; Hansmann, M. L.
A monoclonal antibody, Ki-M1, was produced, and its immunoreactivity was tested by light and electron-microscopic immunohistochemistry. Ki-M1 was found to react with monocytes, cells of the mononuclear phagocyte system (MPS), interdigitating reticulum cells (IDC), and the so-called indeterminate dendritic cells of lymphoid tissue. No reactivity was seen in other human tissues or other hematopoietic cells, including granulocytes and cells of the unstimulated promyelocyte cell line HL-60. Thus, Ki-M1 is the first of the monoclonal antibodies to MPS cells to react with both human IDC and MPS cells. This suggests that IDC and MPS cells may have a common cytogenesis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:6391190
Luxenberg, M N; Guthrie, T H
Eight patients with nine histologically proven BCC or SCC involving the eyelids and periorbital tissues were treated with systemic and/or local (iontophoresis) chemotherapy using cisplatin and doxorubicin. All patients had either refused surgery, would have required extensive procedures, or had medical problems contraindicating surgery. Systemic chemotherapy induced a CR or PR in eight of nine lesions. No patient has required maintenance chemotherapy and no significant toxic side effects were encountered. The length of follow-up ranges from 2 to 50 months. Iontophoretic therapy with cisplatin was used to treat five small foci of new, recurrent or persistent tumor(s) in three of these patients, and resulted in a partial response in all five lesions. Systemic or local chemotherapy offers an alternative to current standard forms of treatment for BCC and SCC in selected cases. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 PMID:3832525
Stogdale, L.; O'Connor, C.D.; Williams, M.C.; Smuts, M.M.S.
A three year old dog was affected with recurrent dyspnea for two months, due to a recurrent pneumothorax. This followed an episode of mild blunt trauma to the thorax and transient strangulation. Conservative therapy of aspiration of air by repeated thoracentesis gave only temporary relief. Thoracic radiographs indicated the presence of a bulla in the right middle lung lobe. An exploratory thoracotomy confirmed the diagnosis, and a lobectomy was successfully performed. The pathogenesis of acquired pulmonary bullae is postulated. Reasons for the predisposition of the right middle lung lobe are outlined. These are related to the anatomy of the right middle bronchus, and include its position between the right pulmonary artery and vein, its oval shape, and the absence of cartilagenous support at its origin. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9. PMID:17422186
Teuscher, E.; Lamothe, P.; Tellier, P.; Lavallée, J. -C.
A toxic nephrosis in calves treated with a drug containing tetracycline degradation products Tetracyclines may prove to be toxic, especially when they are administered in excessive quantity. Toxicity and high mortality were experienced in calves that had been given the recommended dose of a drug which accidentally contained tetracycline degradation products, namely: 4-epianhydrotetracycline, epitetracycline and anhydrotetracycline. Lesions of acute and subacute nephrosis were observed. In calves dying rapidly, an abnormal coloration of skeletal muscles, myocardium and brain was also noted on postmortem examination, and a degeneration of the liver was evident. As the calves were already sick when they received the drug, dehydration and other pathogenic factors might have worsened their condition. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:17422199
Rodesch, G.; Comoy, J.; Hurth, M.; Lasjaunias, P.
The authors report the case of a 37-year-old man with an extracerebral arteriovenous fistula at the skull base, revealed by subarachnoid and intraventricular hemorrhage. The malformation was fed by the neuromeningeal trunk of the ascending pharyngeal artery and drained into left laterobulbar veins. Embolization with bucrylate was performed and occluded totally the shunting zone. A 1-year follow-up angiogram confirmed the good stability of the result, the patient being asymptomatic. This case emphasizes the quality of results that can be obtained with bucrylate in arterioverious fistulas presenting with hemorrhage. It confirms that the external carotid artery must be studied when dealing with intracranial hemorrhage. On the other hand, magnetic resonance imaging and angiography may depict vascular abnormalities but do not always indicate the shunting area, thus the pathologic type of the malformation. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 5p136-b PMID:17170835
Adams, John M.
The discovery of persistent transmissible agents by veterinarians has led to striking advances in the infectious cause of neuropathies of human beings. There is evidence for persisting infection in congenital rubella and the herpes group of viruses including cytomegalovirus infections. Hepatitis types A and B are candidates for inclusion in the category of persisting viral infections. The rubeola or measles virus is established as a persistent virus which causes elevated antibodies in the serum and cerebrospinal fluid of many patients with severe demyelinating disease such as subacute sclerosing panencephalitis and multiple sclerosis. Elevated antibodies against vaccinia virus have been found in the cerebrospinal fluid of some patients with multiple sclerosis and neuromyelitis optica, a rare form of multiple sclerosis. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:165638
Maffulli, N; Regine, R; Carrillo, F; Minelli, S; Beaconsfield, T
Fifty-two knees were examined using real-time high-definition ultrasonography with a 7.5 MHz probe. The extra-articular structures were easily visualized and diagnosis of patellar tendon lesions and Baker's cysts formulated. While the meniscal cartilages were shown as a homogeneous triangular structure between the femoral condyle and the tibial plateau, no lesions were detected. Deeper intra-articular structures, such as the cruciate ligaments, were not shown by the scan, thus their evaluation was not possible. Given its low cost, wide availability, non-invasiveness and patients' acceptability of the technique, ultrasonography may play an important role in the diagnosis of soft tissue lesions in and around the knee joint. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:1623366
Despite successful eradication techniques and specific effective therapies, insect bites and infestations remain a source of great human misery. The current scabies pandemic shows no signs of abating. Bed bugs, which through the ages have been second only to the malarial mosquito as an insect vector of fatal infection, have now been implicated in the transmission of Hepatitis B and possibly African acquired immune deficiency syndrome (AIDS). The incidence of head- and pubic lice is on the rise, the latter paralleling, and often co-existing with, other sexually transmitted diseases. Black widow spiders are native to many populous areas in southern Canada, and the brown recluse spider's range now encompasses Canada, thanks to moving vans and central heating. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21263961
Little, P. B.
The report summarizes a one year period of investigation of death losses in West Malaysian livestock. Lesions and etiological agents are mentioned for cattle, sheep, goats, swine, poultry and companion animals as well as some miscellaneous species. Special observations related to a common paramphistome induced hepatic biliary infestation in cattle, a serious malignant head catarrh outbreak in which possible cattle to cow aerosol transmission occurred. Trismus observed in some cattle with malignant head catarrh was associated with arteriolitis and ganglioneuritis of the V cranial nerve. Parasitic, bacterial, viral toxic and neoplastic diseases are recorded in the various species. The occurrence of fatal chronic fluorosis in laboratory guinea pigs and cerebral nematodiasis in a Thoroughbred racehorse are documented. ImagesFigure 1.FIGURE 2.FIGURE 3.FIGURE 4.FIGURE 5.FIGURE 6.FIGURE 7.FIGURE 8.FIGURE 9.FIGURE 10.FIGURE 11. PMID:761153
Burns, SH; Mierau, DR; Howlett, E
Isolated infection of the sacroiliac joint is a rare cause of low back pain. Delayed diagnosis can result in significant morbidity. The diagnosis may be missed initially if physicians do not consider the possibility of infection. The clinical index of suspicion should increase in the presence of certain historical and examination findings. These include intravenous drug use, immunosuppression, recent infection elsewhere, fever and warmth or swelling over the sacroiliac joint. Two cases of sacroiliac joint pain due to Staphylococcus aureus infection are presented, with an overview of the etiology, diagnosis and management of the disorder. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6(a)Figure 6(b)Figure 7Figure 8
Murdoch, J. C.
The total prescribing in an urban general practice was recorded over a six-month period and classified according to the length of time that drugs were continued. The number of patients receiving any prescription rose with age, as did the total number of items per patient prescribed for; while the continued items rose with age, the number of items prescribed once only per patient remained constant in all age groups. The bulk of the total prescribing was for the elderly and this was mainly for continued items. The classification also shows that certain drug groups are liable to be continued whereas others are virtually always prescribed once only. The implications of these findings for self-audit of prescribing and the care of the elderly in general practice are discussed. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:7452600
Occupational exposure to polychlorinated dioxins, polychlorinated furans, polychlorinated biphenyls, and biphenylenes after an electrical panel and transformer accident in an office building in Binghamton, NY.
Schecter, A; Tiernan, T
A polychlorinated biphenyl (PCB) and tri- and tetrachlorinated benzene-containing electrical transformer was involved in an explosion and fire in a modern office building in Binghamton, New York, on February 5, 1981. Because of an unusual system of air shafts the entire building and adjacent garage became contaminated with toxic chemicals. Polychlorinated dioxins, furans, and biphenylenes were formed as pyrolytic by-products. Before the extent of the chemical contamination was appreciated workers were exposed to these chemicals. Four years after the explosion and after the expenditure of over $22 million for cleaning and other expenses, the building remains closed. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. FIGURE 10. PMID:3928358
Caliari, M. V.; Lana, M.; Leite, V. H.; Tafuri, W. L.
Changes in blood volume can induce morphometric and morphological alterations in the secretory complex of the myoendocrine cells due to the stretching of atrial walls. These alterations were studied by electron microscopy, using dogs infected intraperitonially with Trypanosoma cruzi and necropsied during the acute phase of the infection when congestive heart failure was present. Several changes were observed in the myoendocrine cells of the heart: hypertrophy and hyperplasia of rough endoplasmic reticulum and Golgi complex, increase in telenuclear secretory complex, increase in fusion of type B atrial specific granules (ASG), decrease of the total number of ASG, enlargement of the maximum diameter of type A ASG and a relative increase in the number of type B ASG. These alterations suggest a larger secretory activity of the atrial myoendocrine cells with a larger secretion of atrial natriuretic peptide (ANP). Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7547444
Voullaire, L E; Slater, H R; Petrovic, V; Choo, K H
We report the investigation of an unusual human supernumerary marker chromosome 10 designated "mar del(10)." This marker is present together with two other marker chromosomes in the karyotype of a boy with mild developmental delay. It has a functional centromere at a primary constriction and is mitotically stable. Fluorescence in situ hybridization (FISH) using alpha-satellite and satellite III DNA as probes failed to detect any signal at the primary constriction site. CENP-B protein could not be demonstrated, although the presence of at least some centromeric proteins was confirmed using a CREST antiserum. Consideration of these and other cytogenetic and FISH results supports a mechanism of formation of the mar del(10) chromosome involving the activation of a latent intercalary centromere at 10q25. Images Figure 5 Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 PMID:7684888
Adamson, Peter A.
Canadians have committed themselves to a healthier lifestyle, and many are seeking to look as well as they feel. For patients with realistic expectations, modern techniques of cosmetic facial surgery can enhance appearance and be of psychological benefit. Today most procedures can be done under local anesthesia on an out-patient basis. Facial contour defects can be improved by means of procedures such as rhinoplasty, mentoplasty, otoplasty and malarplasty. Facial rejuvenation surgery to decrease the signs of aging includes the forehead lift, eyebrow and eyelid lift, rhytidectomy, liposuction and chemical peeling. Newer controversial trends in cosmetic facial surgery include collagen implantation and fat transfer for contour defects, and eyelid tattooing. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21263984
Dummett, C. O.
Brief highlights of the careers of 13 Afro-American dentists have been presented. Their professional lives demonstrated both a commitment to the advancement of dentistry and a dedication to the betterment of humanity. Of the 13, three spent their professional lives exclusively in dental education, research, and public health. The remaining 10 were dental clinicians who served patients with competence, care, and concern. Additionally, they contributed to dentistry's image and progress by improving medicodental relations, pioneering in university dental education, engaging in philanthropy, qualifying for dental specialties, exerting leadership in dental professional organizations, integrating dentistry in hospital care, solving community health problems, and participating in all aspects of dental journalism. A sizable portion of their energies was expended in enhancing the quality of life in their communities and the nation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:2651678
Shvarts, S; de Leeuw, D L; Granit, S; Benbassat, J
For more than 70 years, physicians in the Israeli health care system have been employed on a fixed salary rather than on a fee-for-service basis. The present report is a brief review of the origin and development of this unique salaried physician model and its effect on the terms of physicians' employment. Archival documents were reviewed. The salaried physician model was introduced to ensure egalitarian health care for patients rather than equal payment for physicians. It was accepted by physicians because it guaranteed their employment and income. However, over the years, the salaried physician model has evolved into a complex wage scale, with multiple fringe benefits that bypass formal agreements in order to reward individual physicians. In addition, the salaried physician model has encouraged illegal private practice, which is viewed today as one of the major problems of the Israeli Public Health Services. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:9949759
Wikswo, J P; Lin, S F; Abbas, R A
Traditional cable analyses cannot explain complex patterns of excitation in cardiac tissue with unipolar, extracellular anodal, or cathodal stimuli. Epifluorescence imaging of the transmembrane potential during and after stimulation of both refractory and excitable tissue shows distinctive regions of simultaneous depolarization and hyperpolarization during stimulation that act as virtual cathodes and anodes. The results confirm bidomain model predictions that the onset (make) of a stimulus induces propagation from the virtual cathode, whereas stimulus termination (break) induces it from the virtual anode. In make stimulation, the virtual anode can delay activation of the underlying tissue, whereas in break stimulation this occurs under the virtual cathode. Thus make and break stimulations in cardiac tissue have a common mechanism that is the result of differences in the electrical anisotropy of the intracellular and extracellular spaces and provides clear proof of the validity of the bidomain model. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:8599628
Cassidy, J. D.; Potter, G. E.; Kirkaldy-Willis, W. H.
The authors see a large number of back problems, many with complicating features, and are involved in an ongoing assessment of the effectiveness of various treatment modalities, particularly spinal manipulation. This paper deals with spondylolisthesis. Included is a discussion of the definition, classification, etiology and epidemiology of spondylolisthesis. Pain mechanisms are discussed along with the role of conservative and surgical management. Results are presented in a series of cases managed by manipulative methods. The authors conclude that spinal manipulation is of great value in selected cases of back pain in which there is radiographic evidence of spondylolisthesis. No claim is made that such treatment is influencing the spondylolisthesis itself, but that in most cases the spondylolisthesis is an incidental finding, and no contraindication to manipulative therapy. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10
Kumar, P. Pradeep; Taylor, Judith; Scott, Joseph C.; Jacobs, Allan J.; Rojas, John
More than 40 patients with gynecological, genitourinary, and gastrointestinal malignancies, both primary and recurrent but confined to the pelvis, were treated with interstitial irradiation over a four-year period. Interstitial irradiation was the choice of treatment for early carcinoma of the prostate, carcinoma of the anal canal less than T2, recurrent carcinoma of the uterine cervix, and carcinoma of the cervical stump. The authors' experience in treating recurrent carcinoma of the uterine cervix with interstitial irradiation is the basis for the indications for selecting the technique of interstitial irradiation presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10 PMID:6471113
Herenda, Drago; Dukes, Thomas W.
During the period April 1983 to March 1986, lymphoreticular lesions in cattle were surveyed at an Ontario abattoir. Postmortem examination of 171,157 cattle revealed macroscopic lesions in 696 animals (0.4%). The most frequent finding was abscessation of a single lymph node, a finding that was observed in 353 cases (50.7% of animals with lesions/0.2% of total slaughter). Actinobacillary granulomas were present in 252 lymph nodes (36.2%/0.1%). Other specific lesions included mycobacteriosis and mycotic or parasitic lymphadenitis. Cases of nonspecific chronic lymphadenitis or granulomas in lymph nodes, pigmentations, malformations, hyperplasia, and neoplasia were also seen. Abscesses were the most common splenic lesions. One animal had localized lymphangiectasia of the epicardium. ImagesFigure 1., Figure 2., Figure 3., Figure 4., Figure 5., Figure 6. PMID:17423120
Prentiss, R. J.; Mullenix, R. B.; Feeney, M. J.; Howe, G. E.; Steel, J. F.; Cole, J. W.; Flynn, V. J.; Walther, A. B.; Sorensen, M. B.
Catheterization should not be used without true indication. Careful control of hydration, sedation, anesthesia and use of anticholinergic agents before, during and after operation can do a great deal to prevent the need for catheterization. When the procedure is necessary, simple, inexpensive measures of care usually are sufficient. Prophylactic antisepsis before and after, with reexamination of the urine after discontinuance of antiseptic drugs to make sure there is no recrudescence, prevents acute and chronic infections. The catheter recommended for routine male and female catheterization is the 14-16 (French) olive tip coude (Tieman) catheter or the Tieman-Foley. Closed drainage systems are the best. Continuous irrigation is without value. Water is an excellent irrigant. Calcium deposits are prevented by Renacidin® instillation and acetic acid irrigation. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8. PMID:5347199
Tatu, C A; Orem, W H; Finkelman, R B; Feder, G L
Balkan endemic nephropathy (BEN) has attracted increasing attention as a possible environmental disease, and a significant amount of research from complementary scientific fields has been dedicated to its etiology. There are two actual competing theories attempting to explain the cause of this kidney disease: 1) the mycotoxin hypothesis, which considers that BEN is produced by ochratoxin A ingested intermittently in small amounts by the individuals in the endemic regions, and 2) the Pliocene lignite hypothesis, which proposes that the disease is caused by long-term exposure to polycyclic aromatic hydrocarbons and other toxic organic compounds leaching into the well drinking water from low rank coals underlying or proximal to the endemic settlements. We outline the current developments and future prospects in the study of BEN and differentiate possible factors and cofactors in disease etiology. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9799184
Kawamata, T.; Tooyama, I.; Yamada, T.; Walker, D. G.; McGeer, P. L.
Lactotransferrin (LF) expression was investigated immunocytochemically in postmortem brain tissues of normal controls and patients with Alzheimer's disease (AD). The antibody to LF stained some neurons weakly in young adult brains, but it stained many neurons as well as the glia of all types in elderly brains. LF expression was greatly up-regulated in both neurons and glia in affected AD tissue. It was very strongly associated with such extracellular pathological entities as diffuse and consolidated amyloid deposits and extracellular neurofibrillary tangles. In addition, it was identified in a minority of intracellular neurofibrillary tangles, neuropil threads, and degenerative neurites. LF is an iron scavenger and a complement inhibitor. Up-regulation may be a defense mechanism in AD-affected brain tissue. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8494052
Plastination is a unique method for the preservation of biological material for teaching and research. The plastinated specimens are dry, odorless, non-toxic and durable. They can be manipulated by teachers and students without protective equipment like gloves. Invented in 1978 by Doctor Gunther von Hagens from the University of Heidelberg, this technique, that involves the replacement of water by a curable polymer, has spread rapidly all around the world and is actually used in over 250 universities and colleges. To our knowledge, the Université du Québec à Trois-Rivières, is the first institution to use plastinated specimens for teaching anatomy, neuroanatomy, pathology and radiology to students in chiropractic. This paper describes the various steps of the method (fixation, dehydration, impregnation and curing) and presents some examples of the utilization of plastinated specimens. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6
Meltzer, P.; Leibovitz, A.; Dalton, W.; Villar, H.; Kute, T.; Davis, J.; Nagle, R.; Trent, J.
Two human cell lines (UACC-812 and 893), both containing significant amplification of the HER-2/neu gene, were established from biopsy specimens of breast carcinomas. One patient had Stage II breast carcinoma; the other had metastatic disease. Characterisation of these lines has revealed that both are highly aneuploid containing multiple clonal chromosome alterations, have doubling times near 100 h, and are oestrogen and progesterone receptor negative. Electron microscopy demonstrates that both lines contain numerous microvilli, cytoplasmic filaments, multivesicular bodies, and desmosomes. Immunoblot analysis for P-glycoprotein using the monoclonal antibody C219 was negative for both patient cell lines. These relatively rare cell lines may represent a useful model to investigate human breast carcinomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1674877
Berry, J. P.; Henoc, P.; Galle, P.; Pariente, R.
The results of a study of 90 patients are presented. Intrapulmonary mineral deposits were characterized by electron diffraction and electron probe microanalysis. Using this method, pneumoconioses may be distinguidhed from other pneumopathies. In cases of pneumoconiosis, there exists a specific relationship between the etiology of the dust exposure and the crystallographic characteristics of the intrapulmonary deposits. The nature of the deposits may be indicative of a specific type of pneumoconiosis. This method is particularly useful in differentiating between asbestos bodies and ferruginous bodies. The value of the method in general and its importance in the study of pneumoconiosis are discussed. Images Figure 4 Figure 13 Figure 5 Figure 14 Figure 6 Figure 15 Figure 7 Figure 16 Figure 8 Figure 17 Figure 1 Figure 9 Figure 10 Figure 2 Figure 11 Figure 3 Figure 12 PMID:937507
Jedrzynski, M S; Bullock, J D; McGuire, T W; Elder, B L; Bullock, J D
In this article we have reviewed the clinical and bacteriologic aspects of anaerobic orbital cellulitis and have presented six patients to illustrate these points. Physicians who treat patients with orbital cellulitis should have a high index of suspicion for possible instances involving anaerobes, so that appropriate management can be started early. To investigate this problem further, we created an animal model of anaerobic orbital cellulitis. This model may be useful in future studies of the pathogenesis and treatment of this serious and often devastating disease. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 15 FIGURE 16 FIGURE 17 FIGURE 18 FIGURE 19 PMID:1808813
Walters, D A; Smith, B L; Belcher, A M; Paloczi, G T; Stucky, G D; Morse, D E; Hansma, P K
A family of soluble proteins from the shell of Haliotis rufescens was introduced over a growing calcite crystal being scanned in situ by an atomic force microscope (AFM). Atomic step edges on the crystal surface were altered in shape and speed of growth by the proteins. Proteins attached nonuniformly to the surface, indicating different interactions with crystallographically different step edges. The observed changes were consistent with the habit modification induced by this family of proteins, as previously observed by optical microscopy. To facilitate further studies in this area, AFM techniques and certain AFM imaging artifacts are discussed in detail. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 8 FIGURE 9 PMID:9138588
Reuzel, P G; Feron, V J; Spit, B J; Beems, R B; Kroes, R
Cofactors involved in respiratory tract carcinogenesis were studied in Syrian golden hamsters or in rats using benzo(a)pyrene as the carcinogenic agent. These factors included severe tissue damage induced by electro-coagulation, glass fibers administered by intratracheal instillation, acetaldehyde as irritant vapor, food restriction, and nutrients such as vitamin A and saturated and unsaturated fats. In addition, the effects of a combined exposure to four different major gaseous cigarette smoke components--methyl nitrate, isoprene, methyl chloride and acetaldehyde--and to one solid cigarette smoke component--norharman--were examined in short- and long-term inhalation studies. An interesting finding was the carcinogenicity of acetaldehyde, of which the possible mechanism is briefly discussed. Another conspicuous observation was the substantial increase in number and size of lipid droplets in alveolar fibroblasts of hamsters fed a high vitamin A diet. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. PMID:6307680
Clare, V.; Ashman, W.; Broome, P.; Jameson, J.; Lewis, J.; Merkler, J.; Mickiewicz, A.; Sacco, W.; Sturdivan, L.
Wound ballistics assessments traditionally have been based on correlations between some quantification of “ballistic dose” and an empirical/subjective medical quantification of human functional degradation. Although complicated by the highly inhomogeneous nature of the human body and by the voluminous data handling requirements these correlation values were obtained by manual methods. The procedure required a substantial commitment of time and resources, thereby restricting the data base from which incapacitation evaluations were made. The obvious advantages of automated wound ballistics analyses have been realized in the ARRADCOM Computer Man System, capable of duplicating the results of the manual system while reducing the time required for each analysis from three months to less than one day. The versatility of the system also makes it readily adaptable to other ballistic, medical, and paramedical assessment tasks. ImagesFIGURE 1FIGURE 2FIGURE 3FIGURE 4FIGURE 5FIGURE 6FIGURE 7FIGURE 8FIGURE 9FIGURE 10FIGURE 11FIGURE 12FIGURE 13
Garg, R. K.
Neurocysticercosis is the most common parasitic disease of the central nervous system. Varied clinical manifestations occur, due to deposition of larvae of the parasite Taenia solium in cerebral parenchyma, meninges, spinal cord, muscles, eyes and skin. The diagnosis of neurocysticercosis can be made with a fairly high degree of accuracy with the help of computed tomography and magnetic resonance imaging. Serological tests and histopathological examination of subcutaneous nodules provide additional support in establishing the diagnosis. The anticysticercal drugs albendazole and praziquantel have been extensively used, and found to be effective for all types of neurocysticercosis. However, recently controversy has been raised about their safety, and long-term clinical usefulness. Preventive health measures, such as provision of safe drinking water and excretion disposal, still offer the best ways to manage this disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9799883
de Feyter, P.J.; Serruys, P. W.; Nieman, K.; Mollet, N.; Cademartiri, F.; van Geuns, R. J.; Slager, C.; van der Steen, A.F.W.; Krams, R.; Schaar, J.A.; Wielopolski, P.; Pattynama, P.M.T.; Arampatzis, A.; van der Lugt, A.; Regar, E.; Ligthart, J.; Smits, P.
Identification of the vulnerable plaque responsible for the occurrence of acute coronary syndromes and acute coronary death is a prerequisite for the stabilisation of this vulnerable plaque. Comprehensive coronary atherosclerosis imaging in clinical practice should involve visualisation of the entire coronary artery tree and characterisation of the plaque, including the three-dimensional morphology of the plaque, encroachment of the plaque on the vessel lumen, the major tissue components of the plaque, remodelling of the vessel and presence of inflammation. Obviously, no single diagnostic modality is available that provides such comprehensive imaging and unfortunately no diagnostic tool is available that unequivocally identifies the vulnerable plaque. The objective of this article is to discuss experience with currently available diagnostic modalities for coronary atherosclerosis imaging. In addition, a number of evolving techniques will be briefly discussed. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:25696244
Walker, D. H.; McCormick, J. B.; Johnson, K. M.; Webb, P. A.; Komba-Kono, G.; Elliott, L. H.; Gardner, J. J.
Postmortem examination of 21 virologically documented cases of Lassa fever, including 6 complete autopsies, was performed as part of a field study of community-acquired Lassa fever in Sierra Leone. The most consistently observed lesions were hepatocellular, adrenal, and splenic necrosis and adrenal cytoplasmic inclusions. Neither these lesions, nor other milder and less constantly observed lesions such as myocarditis, renal tubular injury, and interstitial pneumonia, appeared severe enough to explain the cause of death in Lassa fever. The central nervous system (CNS) contained no specific lesions. Viral titrations demonstrated high viral content in liver, lung, spleen, kidney, heart, placenta, and mammary gland. Clinical laboratory data included elevation of hepatic enzymes, creatine phosphokinase (CPK), and blood urea nitrogen (BUN). Because of the paucity of pathologic lesions in spite of widely disseminated viral infection, further investigation of humoral inflammatory mechanisms is indicated. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7081389
Svendsgaard, D J; Ward, T R; Tilson, H A; Kodavanti, P R
position are more active than other congeners. Also, congeners with log Kow between 5.2 and 6.6 are generally more active. The estimated combination index indicated that the joint action of PCB congeners in the three commercial mixtures was less than dose additive. The error sum of squares was significantly large, which may indicate a lack of fit of the logistic model. Empirical Bayes estimates (EBE) are weighted averages of model predictions and observations of E50s and can be better estimates than the fitted model when there is a lack of fit. The PRESS statistic for the EBE indicated larger prediction error than for the logistic model, but the EBE provided better estimates of commercial mixture E50s based on dose addition. This may indicate that the logistic model is not incorporating all the information in the single congener data needed to predict mixtures. Images Figure 1. Figure 2. Figure 2. Figure 2. Figure 2. Figure 2. Figure 2. Figure 3. Figure 4. Figure 4. Figure 4. Figure 4. Figure 4. Figure 4. Figure 5. Figure 5. Figure 5. Figure 5. Figure 5. Figure 5. PMID:9349838
Thomas, R S; Yang, R S; Morgan, D G; Moorman, M P; Kermani, H R; Sloane, R A; O'Connor, R W; Adkins, B; Gargas, M L; Andersen, M E
During a 2-year chronic inhalation study on methylene chloride (2000 or 0 ppm; 6 hr/day, 5 days/week), gas-uptake pharmacokinetic studies and tissue partition coefficient determinations were conducted on female B6C3F1, mice after 1 day, 1 month, 1 year, and 2 years of exposure. Using physiologically based pharmacokinetic (PBPK) modeling coupled with Monte Carlo simulation and bootstrap resampling for data analyses, a significant induction in the mixed function oxidase (MFO) rate constant (Vmaxc) was observed at the 1-day and 1-month exposure points when compared to concurrent control mice while decreases in glutathione S-transferase (GST) rate constant (Kfc) were observed in the 1-day and 1-month exposed mice. Within exposure groups, the apparent Vmaxc maintained significant increases in the 1-month and 2-year control groups. Although the same initial increase exists in the exposed group, the 2-year Vmaxc is significantly smaller than the 1-month group (p < 0.001). Within group differences in median Kfc values show a significant decrease in both 1-month and 2-year groups among control and exposed mice (p < 0.001). Although no changes in methylene chloride solubility as a result of prior exposure were observed in blood, muscle, liver, or lung, a marginal decrease in the fat:air partition coefficient was found in the exposed mice at p = 0.053. Age related solubility differences were found in muscle:air, liver:air, lung:air, and fat:air partition coefficients at p < 0.001, while the solubility of methylene chloride in blood was not affected by age (p = 0.461). As a result of this study, we conclude that age and prior exposure to methylene chloride can produce notable changes in disposition and metabolism and may represent important factors in the interpretation for toxicologic data and its application to risk assessment. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 4. Figure 4. Figure 4. Figure 5. Figure 5. Figure 5. Figure 5. PMID:8875160
Pérez-Martínez, C; Ferreras-Estrada, M C; García-Iglesias, M J; Bravo-Moral, A M; Espinosa-Alvarez, J; Escudero-Diez, A
Male mice exposed in utero to alpha-zearalanol (zeranol) or diethylstilbestrol (DES) were analyzed postnatally to evaluate the possible changes on their testicular morphology as part of an examination of the effects of transplacental exposure to non-steroidal estrogens on sensitive tissues. Pregnant NMRI mice were injected subcutaneously with ethyl oleate (0.1 mL) alone (negative control) or with 150 micrograms/kg of body weight of zeranol or DES (positive control) on days 9 and 10 of gestation. Experimental and control male offspring were euthanized at days 45 (n = 47), 90 (n = 44), 180 (n = 40) and 365 (n = 26) after birth and their gonads were examined by light and electron microscopy. The results suggested that prenatal zeranol or DES exposure induced more severe and earlier (at 45 d) testicular abnormalities than in negative control (at 6 mo). These age-related alterations were characterized by regressive changes in the germinal epithelium and Sertoli's cells as well as foci of Leydig's cells around atrophied seminiferous tubules and dysplasia of the rete testis epithelium. On the contrary, the presence of Leydig's cells with immature morphology and their arrangement in sheet could be attributable exclusively to estrogen treatment. The presence of no neoplasm was confirmed. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. PMID:9114959
Samuels, Taube H.
The combination of mammography and clinical examination provides the best means available to detect breast cancer. This article attempts to familiarize the family physician with mammographic terms and to clarify the role of mammography in detecting breast cancer. ImagesFigure 1Figure 2Figures 3-4Figure 5Figure 5Figure 6 PMID:21229125
Vethaak, A D; Jol, J G; Meijboom, A; Eggens, M L; Rheinallt, T; Wester, P W; van de Zande, T; Bergman, A; Dankers, N; Ariese, F; Baan, R A; Everts, J M; Opperhuizen, A; Marquenie, J M
indicate that long-term exposure to chemically contaminated dredged spoil can induce liver neoplasia and other liver lesions in flounder at contaminant levels comparable to those found in the natural environment. Images Figure 1. Figure 2. Figure 2. Figure 2. Figure 2. Figure 3. Figure 3. Figure 3. Figure 3. Figure 4. Figure 5. Figure 5. Figure 6. Figure 7. PMID:8959412
The decades just before and after the founding of the American Public Health Association in 1872 saw an efflorescence of political cartooning and caricature in national-circulation weeklies. Part of the political and social critique that cartoonists and their editors provided the public focused on needs or opportunities for preventing illness and accidents. This paper presents a small selection of editorial cartoons that agitated in support of public health activities over 4 decades. The goals are to illustrate several concerns that rose to national prominence in that era, to examine the kinds of imagery that newspapers and magazine editors offered their readers, and to observe how frequently the public was encouraged to see politicians and commercial interests as responsible for preventable health problems. This discussion focuses exclusively on propagandistic images, leaving aside the reportorial depictions of events in the news and the neutral illustrations of methods and machines in scientific and technical publications. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 PMID:9366637
Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A
Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10064546
Habliston, D L; Hedberg, K K; Birrell, G B; Rempfer, G F; Griffith, O H
Photoelectron imaging is a sensitive surface technique in which photons are used to excite electron emission. This novel method has been applied successfully in studies of relatively flat cultured cells, viruses, and protein-DNA complexes. However, rounded-up cell types such as tumor cells frequently are more difficult to image. By comparing photoelectron images of uncoated and metal-coated MCF-7 human breast carcinoma cells, it is shown that the problem is specimen charging rather than a fundamental limitation of the electron imaging process. This is confirmed by emission current measurements on uncoated monolayers of MCF-7 carcinoma cells and flatter, normal Wi-38 fibroblasts. We report here that sample charging in photoelectron microscopy can be eliminated in most specimens by simultaneous use of two light sources--the standard UV excitation source (e.g., 254 nm) and a longer wavelength light source (e.g., 325 nm). The reduction in sample charging results largely from enhanced photoconduction in the bulk sample and greatly extends the range of cells that can be examined by photoelectron imaging. The contributions of photoconductivity, the electric field of the imaging system, and the short escape depths of the photoelectrons combine to make photoelectron imaging a uniquely sensitive technique for the study of biological surfaces. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:8534832
Multhaupt, H. A.; Gåfvels, M. E.; Kariko, K.; Jin, H.; Arenas-Elliot, C.; Goldman, B. I.; Strauss, J. F.; Angelin, B.; Warhol, M. J.; McCrae, K. R.
The recently cloned very low density lipoprotein (VLDL) receptor binds triglyceride-rich, apolipoprotein-E-containing lipoproteins with high affinity. The observation that VLDL receptor mRNA is abundantly expressed in extracts of tissues such as skeletal muscle and heart, but not liver, has led to the hypothesis that this receptor may facilitate the peripheral uptake of triglyceride-rich lipoproteins. However, little information is available concerning the types of cells that express this receptor in vivo. As expression of the VLDL receptor in the vascular wall might have important implications for the uptake and transport of triglyceride-rich lipoproteins, and perhaps facilitate the development of atherosclerosis in hypertriglyceridemic individuals, we used in situ hybridization and immunohistochemistry to determine whether VLDL receptor mRNA and protein was expressed in human vascular tissue. We observed expression of the receptor by both endothelial and smooth muscle cells within normal arteries and veins, as well as within atherosclerotic plaques. In the latter, the VLDL receptor was also expressed by macrophage-derived foam cells. The widespread distribution of the VLDL receptor in vascular tissue suggests a potentially important role for this receptor in normal and pathophysiological vascular processes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8669483
Gown, A. M.; Tsukada, T.; Ross, R.
The authors have performed immunocytochemical investigations of the distribution of various cell types in human atherosclerotic plaques using monoclonal antibodies specific to smooth muscle cells (CGA7 [Gown et al, J Cell Biol 1985, 100:807-813] and HHF35 [Tsukada et al, Am J Pathol (In press)] ); lymphocytes (T200 antigen); endothelial cells (Factor VIII and the Ulex europeus agglutinin); and macrophages, the latter with a new macrophage-specific antibody HAM56. All studies were performed on methanol-Carnoy's-fixed, paraffin-embedded tissues. In areas of grossly normal aorta, significant numbers of macrophages were noted within areas of diffuse intimal thickening. The cellular composition of the following three types of raised lesions were analyzed: fibro-fatty lesions, which, despite their gross appearance, consistent with fibrous plaques, were composed almost exclusively of macrophages and lymphocytes and almost devoid of smooth muscle cells; fibrous plaques, which were predominantly composed of smooth muscle cells displaying considerable morphologic heterogeneity and an admixture of blood-borne cells; advanced plaques, which were characterized by complex layers of smooth muscle cells and macrophages with considerable variation from region to region. Also noted were foci of medial and even intimal vascularization subjacent to the more advanced plaques. These studies demonstrate the application of monoclonal antibody technology to the study of the cellular composition of human atherosclerotic lesions. Images Figure 1 Figure 2 p195-a Figure 3 Figure 4 Figure 5 Figure 6 p201-a Figure 7 Figure 8 PMID:3777135
Slauson, D. O.; Hahn, F. F.; Benjamin, S. A.; Chiffelle, T. L.; Jones, R. K.
The histopathologic events in the developing acute pulmonary inflammatory reaction to inhaled particles of Yttrium 90 are detailed. In animals that died or were sacrificed during the first year after inhalation exposure, microscopic findings of acute inflammation predominated and included vascular congestion; stasis, focal hemorrhage; edema; various inflammatory cell infiltrates; cytolysis and desquamation of bronchiolar and alveolar epithelium followed by regeneration; vascular injury and repair; and the eventual development of pulmonary fibrosis. Accumulation of alveolar fibrin deposits was an additional characteristic, though not a constant feature of the early stages of radiation pneumonitis. In addition to the direct effects of radiation on pulmonary cell populations, the histopathologic findings were suggestive of diverse activation of various cellular and humoral mediation systems in their pathogenesis. The potential interrelationships of systems responsible for increased vascular permeability, coagulation and fibrinolysis, chemotaxis, and direct cellular injury were discussed and related to the pathogenesis of the microscopic findings characteristic of early pulmonary radiation injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:1258976
House, E. W.; Benditt, E. P.
Electron-microscopic examination of spontaneously occurring coronary arterial lesions in adult spawning steelhead trout showed them to be subendothelial accumulations of modified smooth muscle cells covered by an intact endothelium. Some of the cells in the nodules appeared highly vacuolated and seemed to be associated with varying amounts of collagen and elastin. The internal elastic lamina was often doubled with smooth muscle cells between the layers. The thickness of the internal elastica was altered and, in some lesions, penetrated by smooth muscle cells. In the smallest lesions, smooth muscle cells appeared to be penetrating the internal elastic lamina and were usually close to a highly vacuolated intimal endothelial cell. The underlying medial layer frequently exhibited altered orientation of the cells, with the frequent appearance of increased collagen and amorphous extracellular material. No lipid was present in any lesion. Although vacuolation of endothelial cells suggested some alteration in endothelial cells, at least in developed lesions, no evidence of endothelial denudation over lesions was observed. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 PMID:7294154
Gorza, L.; Menabó, R.; Di Lisa, F.; Vitadello, M.
Intracellular calcium overload of guinea pig cardiomyocytes is accompanied by troponin T cross-linking, which is revealed by changes in immunoreactivity of anti-troponin T antibodies. We presently investigated whether the same process is detectable in the human heart. Immunohistochemistry shows myofibrillar staining with BN-59 anti-troponin T antibody with rare cardiomyocytes in samples obtained at surgery, whereas approximately 50% of myocytes are labeled in heart samples taken at autopsy within 3 hours of death, and every cardiomyocyte is stained after exposure of biopsy sections to 10 mmol/L calcium. Western blot analysis shows reactive polypeptides of approximately 70 and 85 to 90 kd in addition to troponin T in both treated and autopsy heart sections. Neither reactivity in immunohistochemistry nor additional reactive polypeptides in Western blot are detectable when calpain or transglutaminase is inhibited during exposure of sections to high calcium. Troponin T crosslinking occurs also in isolated myofibrils, which show staining with BN-59 at either sarcomeric A or I bands. Labeling with TdT-mediated dUTP nick and labeling (TUNEL) to demonstrate apoptosis reveals DNA fragmentation in BN-59-positive myocytes. Thus, troponin T cross-linking occurs in human cardiac myocytes concomitantly with apoptosis and autopsy autolysis, suggesting that similar cytosolic alterations can be produced by different types of myocyte death. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9176400
Barfoot, R; Denham, S; Gyure, L A; Hall, J G; Hobbs, S M; Jackson, L E; Robertson, D
Peripheral lymph was collected from the skin and liver of sheep, and from the intestine of rats. The dendritic macrophages contained in it were isolated by centrifuging the lymph over a layer of 'Nycodenz'. Similar cells were produced by culturing mononuclear cells from venous blood, but the yields were very small. The numbers of dendritic cells in the lymph from the legs of sheep increased five-fold after xylene had been applied to the skin. Dendritic macrophages displayed abundant class II histocompatibility antigens on their surfaces, as well as immunoglobulins. Although the latter were probably acquired passively, they remained present for several days on cells cultured in vitro. When in vitro, dendritic cells could be shown to phagocytose marker particles, such as latex beads, but their performance was unimpressive compared to macrophages from the peritoneal cavities of rats. In contrast, their ability to phagocytose rapidly T4 phage or influenza viruses unequivocal and striking. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:2807381
Wada, M; Little, R D; Abidi, F; Porta, G; Labella, T; Cooper, T; Della Valle, G; D'Urso, M; Schlessinger, D
One hundred twenty-seven yeast strains with artificial chromosomes containing Xq24-Xqter human DNA were obtained starting from a human/hamster somatic cell hybrid. The clones were characterized with respect to their insert size, stability, and representation of a set of Xq24-Xqter DNA probes. The inserts of the clones add up to 19.3 megabase (Mb) content, or about 0.4 genomic equivalents of that portion of the X chromosome, with a range of 40-650 kb in individual YACs. Eleven clones contained more than one YAC, the additional ones usually having hamster DNA inserts; the individual YACs could be separated by extracting the total DNA from such strains and using it to retransform yeast cells. One of the YACs, containing the probe for the DXS49 locus, was grossly unstable, throwing off smaller versions of an initial 300-kb YAC during subculture; the other YACs appeared to breed true on subculture. Of 52 probes tested, 12 found cognate YACs; the YACs included one with the glucose-6-phosphate dehydrogense gene and another containing four anonymous probe sequences (DX13, St14, cpx67, and cpx6). Xq location of YACs is being verified by in situ hybridization to metaphase chromosomes, and fingerprinting and hybridization methods are being used to detect YACs that overlap. Images Figure 3 Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 PMID:2294758
Schwartz, C. J.; Ghidoni, J. J.; Kelley, J. L.; Sprague, E. A.; Valente, A. J.; Suenram, C. A.
With an increasing interest in the role of the monocyte-macrophage in the pathogenesis of atherosclerosis and as a progenitor of plaque intimal foam cells, a model for the study of foam-cell differentiation in an extravascular environment has been developed. Granulomas were induced in 25 normocholesterolemic (NC) and 28 hypercholesterolemic (HC) rabbits by the subcutaneous injection of 15 ml of 1% carrageenan. Granuloma tissue was harvested at 4, 7, 14, and 28 days and studied by light and transmission electron microscopy. Macrophages and foam cells were isolated by enzymic dispersion with collagenase and cultured for further characterization by scanning electron microscopy, nonspecific esterase (NSE), and oil red O (ORO) staining. Granuloma macrophages from NC rabbits were consistently ORO-negative, contrasting with those from HC rabbits which were strongly ORO-positive, even at 4 and 7 days. With an increasing duration of exposure to hypercholesterolemia, macrophages accumulated increasing amounts of stainable lipid, and in the 28-day HC granulomas, large foam cells distended by lipid inclusions accounted for 70% of the cells present. This model has established that NSE-positive macrophages in HC granulomas accumulate lipid and assume the morphologic characteristics of atheromatous intimal foam cells. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 10 PMID:3966533
Hargis, A. M.; Haupt, K. H.; Hegreberg, G. A.; Prieur, D. J.; Moore, M. P.
Familial canine dermatomyositis is a recently identified disease of collie dogs that resembles human juvenile dermatomyositis. The lesions in the skin and muscles obtained by biopsy from two litters of dogs were characterized for the purpose of determining the similarity of the lesions to those of human dermatomyositis. The cutaneous lesions began between 7 and 11 weeks of age and were present on the face, lips, ears, and skin over bony prominences of the limbs, feet, sternum, and tip of the tail. Histologically the cutaneous lesions frequently consisted of vesicles, pustules, and ulcers on the lips, face, and ears. Neutrophils, lymphocytes, mast cells, and macrophages were present throughout the dermis. Neutrophils and lymphocytes were also present in and around vessels. Between 13 and 19 weeks of age generalized muscle atrophy was noted. The muscle lesions consisted of interstitial lymphocyte, plasma cell, macrophage, and neutrophil accumulation; myofiber degeneration, regeneration, and atrophy; and fibrosis. Perivascular neutrophils, lymphocytes, and plasma cells were also seen. Histologically, the lesions resembled those present in human juvenile dermatomyositis; and these observations, coupled with clinical, immunologic, and clinical pathologic observations presented elsewhere, suggest that familial canine dermatomyositis is an appropriate and potentially useful model for human juvenile dermatomyositis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 PMID:6465285
MacDougal, K C; Johnson, M D; Burnett, K G
Although fish in natural populations may carry high body burdens of both organic and inorganic mercury, the effects of this divalent metal on such lower vertebrates is poorly understood. In this report, inorganic mercury in the form of mercuric chloride (HgCl2) is shown to produce both high-dose inhibition and low-dose activation of leukocytes in a marine teleost fish, Sciaenops ocellatus. Concentrations of inorganic mercury > or = 10 microM suppressed DNA synthesis and induced rapid influx of radiolabeled calcium, as well as tyrosine phosphorylation of numerous cellular proteins. Lower concentrations (0.1-1 microM) of HgCl2 that activated cell growth also induced a slow sustained rise in intracellular calcium in cells loaded with the calcium indicator dye fura-2, but did not produce detectable tyrosine phosphorylation of leukocyte proteins. These studies support the possibility that subtoxic doses of HgCl2 may inappropriately activate teleost leukocytes, potentially altering the processes that regulate the magnitude and specificity of the fish immune response to environmental pathogens. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. PMID:8930553
Katz, M. L.; Rodrigues, M.
Juvenile ceroid lipofuscinosis, or Batten disease, is a hereditary disorder characterized by progressive visual loss, seizures, cognitive and psychomotor deterioration, and early death, usually between 15 and 35 years of age. Individuals with this disease have massive deposits of autofluorescent inclusion bodies in cells of most tissues. The accumulation of these intracellular deposits suggests that juvenile ceroid-lipofuscinosis is a storage disease resulting from the inability of cells to metabolize some normal cellular constituent. It has been reported that the storage material is largely protein, much of which is a specific mitochondrial protein that apparently is not properly metabolized in subjects with Batten disease. The storage bodies were partially purified from the retinas of two siblings who died as a result of juvenile ceroid lipofuscinosis, as well as from the cerebral cortex of an unrelated individual with this disorder. Chromatographic analysis of storage body protein acid hydrolysates indicated that they contained a large amount of the modified amino acid epsilon-N-trimethyllysine. The abundance of this amino acid in the storage protein suggests that the disease may result from excessive methylation or from a failure to demethylate intermediate forms of the stored proteins. Acid hydrolysis also solubilized a fluorescent component from the retinal storage material, suggesting that the stored protein has a bound fluorescent adduct. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1899540
Yates, W. D. G.; Clark, E. G.; Osborne, A. D.; Enweani, C. C.; Radostits, O. M.; Theede, A.
An account is given of an acute outbreak of hemorrhagic enteric disease in 34 young adult boars of primarily Yorkshire breeding at a performance testing station in Western Canada. Two of the boars died. A diagnosis of proliferative hemorrhagic enteropathy was made on the basis of clinical signs, gross necropsy and histopathological lesions. Campylobacter-like bacteria were seen in the apical cytoplasm of epithelial cells of the ileal mucosa by Warthin-Faulkner stain on histological sections, but were not isolated on culture. Treatment with several drugs simultaneously was associated with termination of the outbreak, but the therapeutic effect was not controlled by leaving some animals untreated. Reported sequelae, such as porcine intestinal adenomatosis, were not present at necropsy or slaughter of pigs surviving the outbreak, but all were killed no longer than two months after the first case was observed. This outbreak is discussed in the context of previously reported hemorrhagic enteric conditions of pigs. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:396978
Caspar, D L
Purposeful switching among different conformational states exerts self-control in the construction and action of protein assemblies. Quasi-equivalence, conceived to explain icosahedral virus structure, arises by differentiation of identical protein subunits into different conformations that conserve essential bonding specificity. Mechanical models designed to represent the energy distribution in the structure, rather than just the arrangement of matter, are used to explore flexibility and self-controlled movements in virus particles. Information about the assembly of bacterial flagella, actin, tobacco mosaic virus and the T4 bacteriophage tail structure show that assembly can be controlled by switching the subunits from an inactive, unsociable form to an active, associable form. Energy to drive this change is provided by the intersubunit bonding in the growing structure; this self-control of assembly by conformational switching is called "autostery", by homology with allostery. A mechanical model of the contractile T4 tail sheath has been constructed to demonstrate how self-controlled activation of a latent bonding potential can drive a purposeful movement. The gradient of quasi-equivalent conformations modelled in the contracting tail sheath has suggested a workable mechanism for self-determination of tail tube length. Concerted action by assemblies of identical proteins may often depend on individually differentiated movements. Images Figure 4 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 12 Figure 13 PMID:6894706
Krueger, J W; Denton, A
We describe an extension of the method of Myers et al. (1982) to measure with high precision the uniformity of contractile motions that occur between sarcomeres in the isolated cardiac muscle cell (guinea pig and rat). The image of the striations, observed with modulation contrast microscopy, was detected by a linear array of photodiodes. Sarcomere length was measured greater than 500/s from the frequency of the array's video signal at two selectable regions of the cell. A precision test grating demonstrated that method resolves known differences in the spacing between two contiguous striations to +/- 0.01 micron and that the effects of image translation and microscopic resolution are minor. The distribution of striation spacing appears to be discrete in isolated segments of the cell, and patches of fairly uniform length can be identified that are laterally contiguous. When electrically triggered, contraction is synchronous and the sarcomeres shorten and relengthen smoothly. The contrast between the striations is transiently enhanced during relengthening, an indication that the contracting cell can not be treated as a simple grating. Pauses that occur during late in relengthening (and transient contractile alternans) are characterized by very synchronized activity. These forms of irregular contractile behavior are not explained by desynchronization of a mechanism of release of intracellular calcium. A companion article describes application of the technique to study the nonuniform motions that occur between sarcomeres. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:1540686
Savery, N J; Rhodius, V A; Wing, H J; Busby, S J
Transcription activation at two semi-synthetic Escherichia coli promoters, CC(-41.5) and CC(-72.5), is dependent on the cyclic AMP receptor protein (CRP) that binds to sites centred 41.5 and 72.5 bp upstream from the respective transcription startpoints. An UP-element that can bind the C-terminal domain of the RNA polymerase (RNAP) alpha-subunit was cloned upstream of the DNA site for CRP at CC(-41.5) and downstream of the DNA site for CRP at CC(-72.5). In both cases CRP-dependent promoter activity was increased by the UP-element, but CRP-independent activity was not increased. DNase I footprinting was exploited to investigate the juxtaposition of bound CRP and RNAP alpha-subunits. In both cases, CRP and RNAP alpha-subunits occupy their cognate binding sites in ternary CRP-RNAP promoter complexes. RNAP alpha-subunits can occupy the UP-element in the absence of CRP, but this is not sufficient for open complex formation. The positive effects of binding RNAP alpha-subunits upstream of the DNA site for CRP at -41.5 are suppressed if the UP-element is incorrectly positioned. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7619086
Einhorn, I N
Normally one expects that flame contact is the major cause of injury and death during fires. Analysis of the factors involved in numerous fires has revealed that most deaths were not due to flame contact, but were a consequence of the production of carbon monoxide, nitrogen oxides, and other combustion products, such as aldehydes, low molecular weight alcohols, hydrogen cyanide, and other noxious species. The major emphasis within the scope of this paper relates to the physiological and toxicological aspects of smoke produced during the combustion of materials. Special emphasis is directed toward laboratory procedures which have been developed to determine the qualitative and quantitative analysis of smoke, factors pertaining to smoke development, and to measure the response of laboratory animals exposed to smoke. The effects that fire retardants, incorporated into polymeric materials as a means of improving flammability characteristics, may have on smoke development, the mechanism of polymer degradation, and on the survival response of laboratory animals are also considered. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. PMID:170077
Szomolanyi-Tsuda, E.; Dundon, P. L.; Joris, I.; Shultz, L. D.; Woda, B. A.; Welsh, R. M.
Infection of severe combined immunodeficient mice, which lack T and B lymphocytes, with polyomavirus (PyV) induced an acute hematological disorder leading to the death of the mice by 2 weeks postinfection. The disease was characterized by a dramatic decrease in megakaryocytes, multiple hemorrhages, anemia, thrombocytopenia, splenomegaly, a massive myeloproliferation and splenic erythroproliferation with a defect in maturation of the myeloid elements similar to that in acute leukemia. This pathology in severe combined immunodeficient mice is very different from that of the well-characterized tumor profiles induced by PyV in normal newborn or nude mice. Viral T and capsid (VP1) antigens and viral genome were detected in some cells in the spleen, but not in the majority of the proliferating myeloid cells. This suggests that the myeloproliferation is induced by some indirect mechanism, such as secretion of growth factors or cytokines by virus-infected cells, rather than by direct transformation by PyV. Neither the spread of PyV, its replication in different organs, nor the pathogenesis or the time of death were altered by depleting natural killer cells in vivo by anti-natural killer cell antibodies. Analysis of the spleen leukocyte population indicated that the cells expressed high levels of class I major histocompatibility complex antigens and were resistant to lysis by activated natural killer cells. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8311119
Morimoto, Tadashi; Sasaki, Tomio; Takakura, Kintomo; Ishida, Tsuyoshi
Five patients with chondrosarcoma, grade I or II, and one with mesenchymal chondrosarcoma of the skull base were treated at our clinic between 1967 and 1991. The patients were three men and three women who ranged in age from 21 to 39 years. The presenting symptoms were diplopia, decreased visual acuity, or symptoms of involvement of VIIIth and lower cranial nerves. The duration of the symptoms ranged from 18 months to 14 years. A plain skull x-ray and tomography of the skull, computed tomographic (CT) scans, and magnetic resonance images (MRI) revealed a calcified mass. Angiograms showed an occlusion of the arteries or venous sinuses, or both, in four patients, and a distinct tumor stain in one. The tumors were subtotally removed in all six cases. Two patients received postoperative irradiation for the residual tumor. In one patient, extraocular movement was compromised postoperatively, although in the other five patients there was no aggravation of the neurologic signs. Follow-up CT scans and MRI demonstrated no recurrent tumors nor any enlargement of residual tumors. Based on these findings, we advocate aggressive surgical removal of these tumors, which should be augmented by radiation therapy if the postoperative CT scans or MRI reveal residual tumors. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10 PMID:17170863
Legrand, A.; Greenspan, P.; Nagpal, M. L.; Nachtigal, S. A.; Nachtigal, M.
Human arterial smooth muscle cells transfected with the plasmid pSV3-neo, which contains the SV40 virus early region and the neor gene, developed colonies of morphologically transformed cells. Five cell strains were initiated from these colonies and could be subcultivated for up to 9 months before entering a stage of crisis that ended their life span. Deoxyribonucleic acid (DNA) molecules containing viral sequences were found free and integrated in the transformed cells. The intranuclear SV40 large T antigen and the p53 cellular protein were expressed in the transformed cells. Most of the transformed cells were spindle shaped but some were large and multinucleated. The modal chromosome numbers were in the triploid range, and aberrations, particularly dicentrics, were common. The transcripts for smooth muscle actins were significantly reduced and there were less alpha-actin filaments detected by immunofluorescence. Cytochemical staining disclosed a large accumulation of lipid droplets in the transformed cells incubated with rabbit hypercholesterolemic beta-very-low-density lipoprotein. Chemical analysis showed that cholesteryl esters were significantly elevated in these cells. Phenotypic changes induced in human vascular smooth muscle cells by SV40 early genes are similar to those found in smooth muscle cells from atherosclerotic lesions and may indicate common pathogenetic mechanisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1653520
Couvelard, A.; Scoazec, J. Y.; Feldmann, G.
We compared the expression of cell-cell and cell-matrix adhesion proteins by sinusoidal endothelial cells in normal human liver, in which the endothelial lining of hepatic sinusoids is discontinuous and devoid of basement membrane, and in cirrhosis, during which sinusoids might undergo a process of capillarization and acquire a continuous lining and a typical basement membrane. In normal liver, sinusoidal endothelial cells displayed a very restricted repertory of cell-adhesion molecules: the intercellular adhesion molecules PECAM-1 and CD34 were undetectable and only two integrins, alpha 1 beta 1 and alpha 5 beta 1, were present, whereas the laminin receptors alpha 6 beta 1 and alpha 2 beta 1 were undetectable and the beta 3 integrins were faintly expressed. In capillarized sinusoids, sinusoidal endothelial cells displayed striking changes in their repertory of cell-adhesion molecules, including the expression of PECAM-1 protein and messenger RNAs and the induction of the laminin receptors alpha 6 beta 1 and alpha 2 beta 1. Such changes co-localized with subendothelial laminin deposits. In conclusion, normal sinusoidal endothelial cells express a distinctive set of cell-adhesion molecules, adapted to their structural and microenvironmental characteristics, and this repertory is dramatically modified during sinusoidal capillarization, possibly as a consequence of the concomitant matrix changes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8362973
Feussner, G.; Dobmeyer, J.; Gröne, H. J.; Lohmer, S.; Wohlfeil, S.
Type III hyperlipoproteinemia (HLP) is usually associated with homozygosity for apolipoprotein (apo) E2. We identified a 30-year-old male German of Hungarian ancestry with severe type III HLP and apo E deficiency. The disease was expressed in an extreme phenotype with multiple cutaneous xanthomas. Apo E was detectable only in trace amounts in plasma but not in the different lipoprotein fractions. Direct sequencing of PCR-amplified segments of the apo epsilon gene identified a 10-bp deletion in exon 4 (bp 4037-4046 coding for amino acids 209-212 of the mature protein). The mutation is predictive for a reading frameshift introducing a premature stop codon (TGA) at amino acid 229. By western blot analysis, we found small amounts of a truncated apo E in the patient's plasma. Family analysis revealed that the proband was homozygous--and 10 of 24 relatives were heterozygous--for the mutation. Heterozygotes had, as compared to unaffected family members, significantly higher triglycerides (TG), very low-density lipoprotein (VLDL) cholesterol and a significantly higher VLDL cholesterol-to-serum TG ratio, which is indicative of a delayed remnant catabolism. We propose that the absence of a functionally active apo E is the cause of the severe type III HLP in the patient and that the mutation, even in a single dose in heterozygotes, predisposes in variable severity to the phenotypic expression of the disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8571954
Kimura, Y.; Shiozaki, H.; Hirao, M.; Maeno, Y.; Doki, Y.; Inoue, M.; Monden, T.; Ando-Akatsuka, Y.; Furuse, M.; Tsukita, S.; Monden, M.
The tight junction seals cells together at a subapical location and functionally separates the plasma membrane into an apical and a basolateral domain. This junction is one of the most characteristic structural markers of the polarized epithelial cell. Recently, occludin has been identified as an integral transmembrane protein localizing at the tight junction and directly associated with ZO-1, an undercoat-constitutive cytoplasmic protein. We have investigated occludin expression in conjunction with ZO-1 in normal epithelia and cancers of human digestive tract by immunostaining with a new antibody raised against human occludin. In the normal simple columnar epithelium, occludin was expressed together with ZO-1 as a single line at the apical cell border. However, in the esophagus, which has a stratified squamous epithelium, no occludin expression could be detected, but ZO-1 was expressed in the spinous layer. As for cancers, both occludin and ZO-1 showed the same expression in differentiated adenocarcinoma cells as in normal epithelium, but in poorly differentiated adenocarcinomas, the expression of these two proteins was reduced. There was significant correlation between tumor differentiation and expression of these proteins. These results suggest that occludin, together with ZO-1, is involved in the formation of gland-like structures. In addition, occludin expression can serve as a histopathological indicator for differentiation in gastrointestinal adenocarcinomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9212730
Payne, C. M.
The ultrastructural morphology of platelet-polymorph (platelet-polymorphonuclear leukocyte) rosettes was investigated in EDTA-anticoagulated blood obtained from two patients who exhibited the phenomenon of platelet satellitism. Most of the platelet profiles were attached to the polymorph surface by broad areas of contact. Examination of these broad areas of contact at high magnification revealed an intercellular material of low electron density. This material appeared to form strands, which bridged the intercellular space and spanned the entire area formed by the apposing plasma membranes. Phagocytosis of entire platelets was only observed in 1 case. The platelet profiles that participated in rosette formation revealed a large number of glycogen particles, compared with unattached platelets. Ultrastructural examination of "stress" platelets obtained from five normal subjects treated with steroids similarly showed a large number of glycogen particles, although no rosette formation or phagocytosis of platelets was observed. The etiology of platelet satellitism is discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7223859
Castranova, V; Vallyathan, V
Exposure to coal mine dust and/or crystalline silica results in pneumoconiosis with initiation and progression of pulmonary fibrosis. This review presents characteristics of simple and complicated coal workers' pneumoconiosis (CWP) as well as pathologic indices of acute and chronic silicosis by summarizing results of in vitro, animal, and human investigations. These results support four basic mechanisms in the etiology of CWP and silicosis: a) direct cytotoxicity of coal dust or silica, resulting in lung cell damage, release of lipases and proteases, and eventual lung scarring; b) activation of oxidant production by pulmonary phagocytes, which overwhelms the antioxidant defenses and leads to lipid peroxidation, protein nitrosation, cell injury, and lung scarring; c) activation of mediator release from alveolar macrophages and epithelial cells, which leads to recruitment of polymorphonuclear leukocytes and macrophages, resulting in the production of proinflammatory cytokines and reactive species and in further lung injury and scarring; d) secretion of growth factors from alveolar macrophages and epithelial cells, stimulating fibroblast proliferation and eventual scarring. Results of in vitro and animal studies provide a basis for proposing these mechanisms for the initiation and progression of pneumoconiosis. Data obtained from exposed workers lend support to these mechanisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10931786
Franke, F. E.; Schachenmayr, W.; Osborn, M.; Altmannsberger, M.
Immunoreactivities of 35 different monoclonal antibodies (MAbs) that detect intermediate filaments were studied systematically on serial cryostat sections of 14 well-defined human gliomas (five astrocytomas, three oligodendrogliomas, six glioblastomas) and on normal brain. Glial fibrillary acidic protein (GFAP), vimentin, desmin, neurofilaments, and broad-specificity keratin MAbs, as well as MAbs that recognize several or only single keratin polypeptides, were used. Unexpected reactivities were surprisingly frequent. As these may lead to diagnostic confusion and misinterpretation on this material, the authors investigated these phenomena more thoroughly. Four major sources of artifactual staining were found: 1) positive staining attributable to the rabbit gamma G immunoglobulins used in the alkaline phosphatase anti-alkaline phosphatase technique; 2) certain desmin and keratin MAbs cross-reacted with astrocytic glia and with other brain-specific epitopes; 3) technical difficulties; 4) some MAbs directed against neurofilaments and keratins showed unexpected reactivities only on individual anaplastic gliomas. The implications of these findings for intermediate filament typing of neuropathologic material are discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1713022
Kawahara, E.; Shiroo, M.; Nakanishi, I.; Migita, S.
Azocasein-induced amyloid A (AA) amyloidosis in CBA/K1Jms mice was investigated to elucidate a preference of serum amyloid A (SAA) deposition in the spleen. By indirect immunofluorescence using anti-SAA/AA antibodies the initial deposition of SAA/AA was recognized in the marginal zone of spleen at 20 days after azocasein injection. Indirect immunofluorescence using anti-fibronectin antibodies also showed meshwork positivity in the corresponding area more intensely than that in controls. Immunoelectron microscopy using anti-SAA/AA revealed the presence of positively stained flocculent materials on cell surfaces of macrophages in the marginal area in addition to amyloid fibril. The tissue fibronectin rapidly increased in the spleen and maintained 10 times more than that of controls until the 20th day. Binding assay of SAA on frozen sections revealed the presence of SAA-binding substances in the perifollicular area. Affinity chromatographic assay showed fibronectin have a binding capacity to SAA1 and SAA2. By binding assay on the microtiter plate, SAA had more affinity to fibronectin than those of heparan sulfate, collagen type I, or serum amyloid P component. These results indicate that fibronectin plays an important role in the development of amyloidosis by working as a linking protein between SAA and the cell surface of macrophages. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 Figure 8 PMID:2757120
Thein, Jill M.; Brody, Lori Thein
Objective: To describe the application of aquatic rehabilitative exercise to injuries of the upper extremity. Background: Water has been used for centuries as a medium for rehabilitation, relaxation, and training. Athletes use the pool to rehabilitate specific injuries, as a training medium during injury recovery, and as an alternative training site. The pool can be used to rehabilitate a number of upper extremity impairments, as well as to restore functional movement patterns in a resistive medium. Description: Exercises can be modified to be performed in pools of varying size and depth. Well-chosen equipment will enhance the rehabilitative opportunities for the clinician and patient. Clinical Advantages: All aspects of the rehabilitation program, including passive stretching, resistive exercise, functional movement patterns, and cardiovascular training, can take place in the same location. The water's warmth and buoyancy enhance stretching, while the buoyancy allows initiation of resistive exercise at a low level. The water's viscosity provides resistance throughout a movement pattern in any plane. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9. PMID:16558651
Banks-Schlegel, S. P.; McDowell, E. M.; Wilson, T. S.; Trump, B. F.; Harris, C. C.
Light-microscopic immunocytochemistry and electron microscopy demonstrated that adenocarcinomas (AC) and squamous cell (epidermoid) carcinomas (SCCs) of human lung contained keratin proteins in the form of tonofilament bundles. However, moderately differentiated (md) SCCs contained abundant keratin, whereas poorly differentiated (pd) SCCs and all ACs contained lesser amounts. Lung tumors with the diagnosis of AC or SCC, as defined by WHO criteria, were also analyzed by immunoprecipitation techniques for the presence of keratin proteins. Regardless of the degree of tumor differentiation, SCCs contained a 44 kd keratin which was lacking in ACs. Interestingly, normal bronchial epithelium also contained the same 44 kd keratin. In addition, as SCCs became more differentiated, they exhibited even greater differences in the profile of synthesized keratins. Specifically, the relative abundance of the intermediate-sized keratins (57 and 59 kd) was increased in the md SCCs. Although keratin protein patterns appear to be a valuable adjunct in distinguishing AC from SCC, their usefulness as a diagnostic tool will require survey of a larger number of poorly differentiated tumors. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:6198920
Gillett, N. A.; Muggenburg, B. A.; Mewhinney, J. A.; Hahn, F. F.; Seiler, F. A.; Boecker, B. B.; McClellan, R. O.
Primary liver tumors developed in Beagle dogs exposed by inhalation to aerosols of 238PuO2. Initial deposition of 238PuO2 in the respiratory tract was followed by translocation of a portion of the 238Pu to the liver and skeleton, which resulted in a large dose commitment and tumor risk to all three tissues. In a population of 144 dogs exposed to 238PuO2, 112 dogs died or were killed 4000 days after 238Pu exposure, 100 dogs had osteosarcoma, and 28 dogs had lung cancers. At increasing times after exposure, however, liver lesions have become more pronounced. Ten primary liver tumors in nine animals were diagnosed in the dogs dying before 4000 days after exposure. An additional five primary liver tumors in three dogs occurred in 9 animals killed after 4000 days after exposure. The majority of these tumors have been fibrosarcomas. The liver tumors were usually not the cause of death, and rarely metastasized. The occurrence of liver tumors in this study indicates that 238Pu is an effective hepatic carcinogen. Liver carcinogenesis is assuming an increasing importance in this study at late times after inhalation exposure. These results suggest that the liver may be an important organ at risk for the development of neoplasia in humans at time periods long after inhalation of 238Pu. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:3142267
Wayne, Howard H.
The apexcardiogram (acg), when recorded serially in patients with acute myocardial infarction (ami), preinfarction angina (pia) and stable ischemic heart disease (ihd), appeared to reflect the abnormal patterns of contraction of the left ventricle in these conditions. Thus, paradoxical bulging (dyskinesis) of the systolic wave or increased “a” wave amplitude with gradual recovery over several weeks was found in all 60 patients with documented ami and in 18 of 20 patients with pia. Electrocardiogram changes were noted, however, in only eight of the pia patients. Changes in the acg frequently antedated ischemia in the ecg. Paradoxical bulging of the systolic wave of the acg was additionally noted in patients during the pain of angina pectoris but this promptly disappeared after the administration of nitroglycerine. Patients with classic angina often had normal resting ecg's but abnormal resting acg's. In contrast to the relatively transient abnormalities noted above, the acg remained unchanged in most patients with stable ihd during follow-up of three months to two years. Patients undergoing coronary bypass operations, however, showed immediate improvement in the acg in the postoperative period. These results suggest the acg reflects the contractile pattern of the left ventricle, and may be an indirectly recorded ventriculogram. Its enhanced sensitivity and the earlier development of changes in comparison to the ecg make this a valuable tool in the study of patients with heart disease. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:5008498
Swartz, P D; Beck, B W; Ichiye, T
Redox potentials often differ dramatically for homologous proteins that have identical redox centers. For two types of iron-sulfur proteins, the rubredoxins and the high-potential iron-sulfur proteins (HiPIPs), no structural explanations for these differences have been found. We calculated the classical electrostatic potential at the redox site using static crystal structures of four rubredoxins and four HiPIPs to identify important structural determinants of their redox potentials. The contributions from just the backbone and polar side chains are shown to explain major features of the experimental redox potentials. For instance, in the rubredoxins, the presence of Val 44 versus Ala 44 causes a backbone shift that explains a approximately 50 mV lower redox potential in one of the four rubredoxins. This result is consistent with experimental redox potentials of five additional rubredoxins with known sequence. Also, we attribute the unusually lower redox potentials of two of the HiPIPs studied to a less positive electrostatic environment around their redox sites. Finally, molecular dynamics simulations of solvent around static rubredoxin crystal structures indicate that water alone is a major factor in dampening the contribution of charged side chains, in accord with experiments showing that mutations of surface charges produce relatively little effect on redox potentials. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:8968568
Schoonderwoerd, Matt; Doige, Cecil E.; Wobeser, Gary A.; Naylor, Jonathan M.
Fat stores and organ weights were assessed in calves at birth (n=5) and after seven days of milk (n=5) or electrolyte (n=5) feeding. Compared to newborn calves, milk-fed calves had a significant (p < 0.05) redistribution of fat from perirenal area to bone marrow. The thymus also involuted during milk feeding. In electrolyte-fed calves there was a significant loss of perirenal and bone marrow fat. The visible omental, mesenteric and subcutaneous fat stores were depleted. Epicardial fat stores were not visibly affected. There was a high correlation between bone marrow crude fat and bone marrow dry matter (R=0.92). This suggests that dry matter estimations can be used to assess bone marrow fat stores. Perirenal fat may be intermediate in type between brown and white adipose tissue because it is mobilized in response to fasting, and formalin fixed perirenal fat did not contain detectable levels of thermogenin. ImagesFigure 1., Figure 2., Figure 3., Figure 4., Figure 5.Figure 6., Figure 7., Figure 8., Figure 9. PMID:17422704
Lee, Myung-Shik; Gu, Danling; Feng, Lili; Curriden, Scott; Arnush, Marc; Krahl, Troy; Gurushanthaiah, Deepak; Wilson, Curtis; Loskutoff, David L.; Fox, Howard; Sarvetnick, Nora
Transgenic mice expressing transforming growth factor-β1 (TGF-β1) in the pancreatic β-islet cells directed by human insulin promoter were produced to study in vivo effects of TGF-β1. Fibroblast proliferation and abnormal deposition of extracellular matrix were observed from birth onward, finally replacing almost all the exocrine pancreas. Cellular infiltrates comprising macrophages and neutrophils were also observed. Plasminogen activator inhibitor was induced in the transgenic pancreas as well as fibronectin and laminin, partly explaining accumulation of extracellular matrix. TGF-β1 inhibited proliferation of acinar cells in vivo as evidenced by decreased bromodeoxyuridine incorporation. Development of pancreatic islets was dysregulated, resulting in small islet cell clusters without formation of normal adult islets; however, the overall islet cell mass was not signfifcantly diminished. Additional transgenic lines with less pronounced phenotypes had less expression of TGF-β1 transgene. These findings suggest that TGF-β1 might be a mediator of diseases associated with extracellular matrix deposition such as chronic pancreatitis, and this mouse model will be useful for further analysis of the in vivo effects of TGF-β1, including its potential for immunosuppression. Imagesp43-aFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:7604884
Plenat, F.; Klein-Monhoven, N.; Marie, B.; Vignaud, J. M.; Duprez, A.
Antisense oligonucleotides have the ability to inhibit individual gene expression in the potential treatment of cancer and viral diseases. However, the way parenterally administered oligonucleotides distribute themselves into healthy tissues or tumors is poorly understood. In this study, the cell and tissue distribution of two modified or unmodified phosphodiester pentadeca-beta-oligonucleotides intravenously administered to healthy or tumor-bearing nude mice was assessed by autoradiography as well as by direct fluorescence and immunoenzymatic histological methods. Resistance of oligonucleotides to degradation by nuclease activity was previously studied in vitro. Using these methods we were able to show the following: 1) within minutes, oligonucleotides permeate all cells and tissues with the exceptions of erythrocytes and intervertebral discs; 2) cell and tissue distribution does not depend on the sequence of the given oligonucleotide; 3) concentration of oligonucleotides is higher within the connective tissue cells than in the interstitial matrix; 4) after uptake, oligomers partition throughout all of the cellular compartments, including at the highest intracellular concentrations in the nuclei; 5) oligonucleotides penetrate easily the tumor cell compartments, oligonucleotide diffusion being unimpeded by the extracellular matrix. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:7604874
Braun, L.; Mikumo, R.; Mark, H. F.; Lauchlan, S.
We have established three cell lines from keratinizing and nonkeratinizing cervical carcinomas with distinct growth properties in vitro and in vivo. Each cell line contained human papillomavirus type 16 DNA sequences, but the lines differed in the physical state of the viral genome present in the cells. A high copy number of episomal human papillomavirus type 16 DNA sequences was detected in the TC-140 line derived from a keratinizing cervical cancer. This cell line had an aneuploid karyotype, did not grow in soft agarose, and formed benign cystlike nodules in nude mice, similar in morphology to well-differentiated areas of the primary tumor. Only integrated human papillomavirus type 16 sequences were detected in the TC-146A and TC-146B lines established from a nonkeratinizing large-cell cervical carcinoma. These cell lines exhibited reduced sensitivity to transforming growth factor-beta 1 and produced invasive, but not progressively growing, tumors in nude mice. These cell lines should complement existing in vitro models of cervical carcinogenesis and provide useful tools for understanding the importance of virus integration in the transformation process as well as the cellular and molecular basis for tumor progression. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8395773
Kitamura, H.; Kameda, Y.; Nakamura, N.; Nakatani, Y.; Inayama, Y.; Iida, M.; Noda, K.; Ogawa, N.; Shibagaki, T.; Kanisawa, M.
To elucidate the pathogenesis of bronchioloalveolar lung carcinoma (BAC), we evaluated the lesion size, growth fraction, and p53 overexpression of atypical adenomatous hyperplasia (AAH) and early stage BAC. AAH was classified as showing low grade or high grade atypia. AAH-like carcinoma, presumably very early stage BAC, was distinguished from AAH in that it exhibited remarkable atypia suggestive of malignant potential and from overt BAC in that it lacked unequivocal malignant features, including invasive/destructive growth. The growth fraction was determined immunohistochemically in terms of the Ki-67 labeling index. The overexpression of p53 was evaluated by assessing the nuclear accumulation of immunoreactive p53 protein. Both the lesion size and the growth fraction increased from low grade AAH, to high grade AAH, to AAH-like carcinoma, and to overt adenocarcinoma. The overexpression of p53 in AAH-like carcinoma was similar to that in overt adenocarcinoma and was more frequent than that in AAH. Our findings indicate that AAH, AAH-like carcinoma, and overt BAC represent different categories, although the cellular events occurring in these lesions presumably represent a continuous spectrum of the changes that are reflected in the cytomorphology and lesion size. The findings here suggest that AAH and AAH-like carcinomas constitute a population of heterogeneous lesions representing different steps toward overt BAC. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7717455
Merriam, J C; Stalnecker, M C; Merriam, G R
The initial stages in the rehabilitation of a male child with severe microblepharon, corneal opacities, bilateral facial clefts, bilateral complete cleft lip and palate, and unilateral syndactyly are described. Review of the literature suggests that severe microblepharon is associated with other craniofacial anomalies, and often the child is stillborn or retarded. Surviving children have been abandoned because of their appearance. The child described in this case appears to be unique because his intelligence is normal, and, to our knowledge, this is the first reported case of penetrating keratoplasty after reconstruction of functional eyelids. The principal problems after corneal grafting appear to have been chronic partial exposure due to inadequate lid length and a poor Bell's reflex and the persistence of a rim of vascularized fibrous tissue around the corneal graft. Future reconstructive surgery is outlined. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 16 FIGURE 17 FIGURE 18 FIGURE 19 FIGURE 20 FIGURE 21 FIGURE 22 PMID:2979029
Wagner, K; Keyes, E; Kephart, T W; Edwards, G
We present an analytical, Green-function-based model for the electric potential of DNA in solution, treating the surrounding solvent with the Debye-Huckel approximation. The partial charge of each atom is accounted for by modeling DNA as linear distributions of atoms on concentric cylindrical surfaces. The condensed ions of the solvent are treated with the Debye-Huckel approximation. The resultant leading term of the potential is that of a continuous shielded line charge, and the higher order terms account for the helical structure. Within several angstroms of the surface there is sufficient information in the electric potential to distinguish features and symmetries of DNA. Plots of the potential and equipotential surfaces, dominated by the phosphate charges, reflect the structural differences between the A, B, and Z conformations and, to a smaller extent, the difference between base sequences. As the distances from the helices increase, the magnitudes of the potentials decrease. However, the bases and sugars account for a larger fraction of the double helix potential with increasing distance. We have found that when the solvent is treated with the Debye-Huckel approximation, the potential decays more rapidly in every direction from the surface than it did in the concentric dielectric cylinder approximation. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 7 PMID:9199767
Welch, R B
Two unusual events concerning intraocular foreign bodies are presented. The first patient had an occult or unsuspected intraocular foreign body. He showed iridoplegia with mydriasis, siderosis iridis, and an intraocular piece of iron lying posteriorly near the retina. The foreign body was removed and the patient regained normal iris color and pupillary activity. His vision remains 20/15 six years postoperatively dispite ensuing retinal detachment one year after removal of the foreign body. The second patient was a young boy injured by a blasting cap explosion. He lost one eye from the injury and had a piece of intraocular brass in his left eye. In spite of the development of chalcosis and a mature cataract the lens gradually shrank in the pupillary space permitting a clear aphakic area and 20/25 vision. The brass fragment migrated forward and inferiorly and was finally extruded under the conjunctiva five years later, where it was removed and chemically analyzed by x-ray diffraction. Images FIGURE 1 A FIGURE 1 B FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:1108372
Shields, M B
When surgical attempts to control glaucoma by improving aqueous outflow are not successful, the alternative approach is usually to reduce aqueous inflow by a cyclodestructive procedure. Cyclodestructive elements that have been tried in the past include diathermy, electrolysis, and beta irradiation. Cyclocryotherapy is presently the most commonly used cyclodestructive procedure, although this operation has significant limitations, and newer techniques are being evaluated utilizing laser energy or ultrasonic radiation. Each of these procedures uses a transcleral approach, which has the disadvantages of (1) the inability to precisely quantitate the destruction of the ciliary processes, and (2) damage to adjacent tissue. Transpupillary cyclophotocoagulation minimizes these problems, but is limited to the small number of eyes in which adequate gonioscopic visualization of the ciliary processes can be achieved. An alternative approach for aphakic eyes is intraocular cyclophotocoagulation, utilizing an endophotocoagulator through a pars plana incision. Depending on the status of the eye, visualization for this technique can be accomplished either by the transpupillary route or with an endoscope. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:3832531
Clarke, Adrian K.; Critchley, Christa
In vivo radiolabeling of chloroplast proteins in barley (Hordeum vulgare L. cv Corvette) leaves and their separation by one-dimensional electrophoresis revealed at least seven heat-shock proteins between 24 and 94 kD, of which most have not been previously identified in this C3 species. Fractionation into stromal and thylakoid membrane components showed that all chloroplast heat-shock proteins were synthesized on cytoplasmic ribosomes, translocated into the chloroplast, and located in the stroma. Examination of stromal preparations by native (nondissociating) polyacrylamide gel electrophoresis revealed the presence of a high-molecular mass heat-shock protein complex in barley. This complex was estimated to be 250 to 265 kD in size. Dissociation by denaturing polyacrylamide gel electrophoresis revealed a single protein component, a 32-kD heat-shock protein. The synthesis of this protein and the formation of the heat-shock protein complex were dependent on functional cytoplasmic ribosomes. Immunological studies showed that the heat-shock protein complex did not contain any proteins homologous to the α-subunit of ribulose bisphosphate carboxylase oxygenase subunit-binding protein. Other features about the complex included the absence of nucleic acid (RNA or DNA) and its nondissociation in the presence of Mg2+/ATP. These results suggest that the heat-shock protein complex in barley chloroplasts is a homogeneous octamer of 32-kD subunits. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:16653243
Naito, M.; Suzuki, H.; Mori, T.; Matsumoto, A.; Kodama, T.; Takahashi, K.
Macrophage scavenger receptors are trimeric membrane glycoproteins implicated in the pathologic deposition of cholesterol in arterial walls during atherogenesis. Two types of cDNAs for functional human receptors have been cloned, but their physiologic roles remain obscure. To study the expression of these receptors, the authors generated antibodies against scavenger receptor type-specific synthetic peptide. Immunohistochemical examination using these antibodies and other anti-human receptor antibodies shows that type I and type II receptor proteins can be detected in foam cells in various stages of atherosclerosis, most evidently in fatty streaks. Co-expression of the two types of receptor protein was also detected in macrophages of various organs. Both types of the protein were detected on the surface and the membrane of endosomes in macrophages. These results indicate that both type I and type II scavenger receptors are expressed and functionally active in physiologic and pathologic conditions. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1519666
Darrow, V. C.; Alvord, E. C.; Mack, L. A.; Hodson, W. A.
With the development and routine use of real-time ultrasound scanning, it has been possible to collect 20 autopsy cases of infants in whom the ultrasound scan was first normal and then showed evidence of subependymal/intraventricular hemorrhage (SEH/IVH). Analysis of these cases with known postnatal origin of the hemorrhage permitted the development for the first time of a time scale to characterize the temporal evolution of the histopathologic reactions to hemorrhage in the premature human brain. This time scale was then used to define the histologic stage of the lesions in 27 other cases of infants who had a scan demonstrating SEH/IVH prior to death but who had not a previously normal scan. Only 2 cases were found to lie off the original scale, indicating a prenatal onset of the hemorrhage in about 5% of the total cases. Thus, postnatal events immediately preceding the onset of the hemorrhage are more likely to be implicated in the pathogenesis of SEH/IVH than prenatal or obstetric events. Comparison with similar reactions in the adult indicate that the early reactions by macrophages occur at about the same rate but the routine transfer of iron from macrophages to astrocytes and the much slower rate of absorption to form a cyst in the adult combine to form a complicated pattern that requires a different set of criteria for the intermediate and late stages in the adult. Images Figure 4 Figure 3 Figure 9 Figure 2 Figure 1 Figure 5 Figure 7 PMID:3276212
Nukada, H.; Dyck, P. J.
Polystyrene microspheres, the size chosen to plug capillaries and precapillaries, were injected into the arterial supply of rat sciatic nerves. They produced widespread segmental occlusion of capillaries in lower limb nerves. The clinical and pathologic effect was dose-related. One million microspheres produced selective capillary occlusion but no nerve fiber degeneration; approximately 6 million microspheres also produced selective capillary occlusion and associated foot and leg weakness, sensory loss, and fiber degeneration, beginning in a central core of the distal sciatic nerve; 30 million microspheres caused both capillary and arterial occlusion and a greater neuropathologic deficit. From these observations it is inferred that 1) occlusion of isolated precapillaries and capillaries does not produce ischemic fiber degeneration; 2) occlusion of many microvessels results in central fascicular fiber degeneration, indicating that these cores are watershed regions of poor perfusion; and 3) stereotyped pathologic alterations of nerve fibers and Schwann cells are related to dose, anatomic site, and time elapsed since injection. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:6326580
Rafferty, T. D.; Lippmann, H.
Recent advances in technology have allowed application of transesophageal echocardiography to intraoperative care of critically ill patients. Early clinical application primarily involved evaluation of left ventricular regional wall motion. However, valid intraoperative use of transesophageal echocardiography should also encompass systematic assessment of the entire heart as well as the great vessels. This report describes a 10-step sequence of single plane, two-dimensional echocardiographic views which constitute a basic patient examination capable of being performed by a practitioner whose primary responsibility is the delivery of anesthesia care. A 5-step color flow Doppler examination sequence is also presented. These views complement the two-dimensional echocardiographic steps. Representations of methods for grading Doppler-defined valvular regurgitation complete the report. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 PMID:7825339
Eggleston, P A; Buckley, T J; Breysse, P N; Wills-Karp, M; Kleeberger, S R; Jaakkola, J J
The prevalence and severity of asthma has increased in the last 20 years, and the greatest increase has been seen among children and young adults living in U.S. inner cities. The reasons for this increase are obviously complex, but include environmental exposures to allergens and pollutants, changing patterns of medication, and the psychosocial stresses of living in poor inner-city neighborhoods. This paper presents an overview of environmental, immunologic, and genetic factors associated with asthma morbidity and mortality. This overview can be used to provide a framework for designing an interdisciplinary research program to address the complexities of asthma etiology and exacerbation. The strongest epidemiologic association has been found between asthma morbidity and the exposure of immunologically sensitive asthmatic patients to airborne allergens. Our current understanding of the process of sensitization suggests that there is a strong genetic predisposition to form IgE to allergenic proteins on airborne particles. Much of this work has been conducted with animal models, but in a number of instances, specific confirmation has been reported in humans. Sensitized individuals respond to inhaled exposure with immediate mast-cell dependent inflammation that may be augmented by pollutant particles, especially diesel exhaust particles. Relatively little is known about the methods of assessing exposure to airborne pollutants, especially biologically active particulates. However, to examine the relationship of morbidity in genetically predisposed individuals, it will be important to determine the most relevant method of making this assessment. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10346992
Asher, S A; Pershan, P S
The alignment of dilauryl-, dimyristoyl-, and dipalmitoylphosphatidylcholine at various water concentrations into large oriented monodomain multilayers by annealing at elevated temperatures (Powers and Clark, 1975, Proc. Natl. Acad. Sci. U.S.A. 72:840; Powers and Pershan. 1977. Biophys. J. 20:137) is accompanied by the formation and subsequent dissolution of various defect structures. Some of these defects appear similar to those observed in thermotropic and other lyotropic liquid crystals, reflecting the lamellar structure of these materials. The formation and evolution of defects during the alignment of the lipids into the defect-free, monodomain, multilamellar geometry is studied using polarized microscopy. A combination of polarized and dark-field microscopy facilitated characterization of the defects; specific structural models are proposed. A new alignment technique involving compression and dilation of the lipid, which effects sample alignment at temperatures that are lower than those required by the Powers technique, is described. Lower temperature alignment avoids thermal decomposition that will sometimes occur if the lipid is maintained at elevated temperatures for prolonged periods. With this technique, samples (80 micrometer thick) of dilaurylphosphatidylcholine with 20% water by weight were aligned at room temperature. Images FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 15 PMID:263691
Filosa, S.; Giacometti, N.; Wangwei, C.; De Mattia, D.; Pagnini, D.; Alfinito, F.; Schettini, F.; Luzzatto, L.; Martini, G.
X-chromosome inactivation in mammals is regarded as an essentially random process, but the resulting somatic-cell mosaicism creates the opportunity for cell selection. In most people with red-blood-cell glucose-6-phosphate dehydrogenase (G6PD) deficiency, the enzyme-deficient phenotype is only moderately expressed in nucleated cells. However, in a small subset of hemizygous males who suffer from chronic nonspherocytic hemolytic anemia, the underlying mutations (designated class I) cause more-severe G6PD deficiency, and this might provide an opportunity for selection in heterozygous females during development. In order to test this possibility we have analyzed four heterozygotes for class I G6PD mutations: two with G6PD Portici (1178G-->A) and two with G6PD Bari (1187C-->T). We found that in fractionated blood cell types (including erythroid, myeloid, and lymphoid cell lineages) there was a significant excess of G6PD-normal cells. The significant concordance that we have observed in the degree of imbalance in the different blood-cell lineages indicates that a selective mechanism is likely to operate at the level of pluripotent blood stem cells. Thus, it appears that severe G6PD deficiency affects adversely the proliferation or the survival of nucleated blood cells and that this phenotypic characteristic is critical during hematopoiesis. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8808605
Shih, W. J.; Pulmano, C.; Han, J. K.; Lee, C.
A patient with acute right abdominal pain and nausea underwent various diagnostic imaging studies, including ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), technetium-99m DTPA renal study, and contrast arteriogram. The 99mTc renal study showed a linear photopenic area along the lateral cortical aspect of the right kidney and a focal cortical defect in the left kidney. These lesions corresponded to the findings of US, CT, MRI, and contrast angiography. Because of a suspected malignant mass, a CT-guided aspiration biopsy of the right kidney was performed that resulted in bloody fluid without malignant cells. The patient's condition was diagnosed as intrarenal and subcapsular renal hematoma. The patient was treated conservatively and followed up with CT and US studies. Sequential CT and US demonstrated gradual reduction of the size of the hematoma, and complete resolution was confirmed by US 1.5 years later. As long as underlying pathology can be ruled out, conservative management of spontaneous renal subcapsular hematoma is recommended. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:10976177
Flanagan, L A; Cunningham, C C; Chen, J; Prestwich, G D; Kosik, K S; Janmey, P A
Phosphatidylinositol bisphosphate (PIP2) serves as a precursor for diacylglycerol and inositol trisphosphate in signal transduction cascades and regulates the activities of several actin binding proteins that influence the organization of the actin cytoskeleton. Molecules of PIP2 form 6-nm diameter micelles in water, but aggregate into larger, multilamellar structures in physiological concentrations of divalent cations. Electron microscopic analysis of these aggregates reveals that they are clusters of striated filaments, suggesting that PIP2 aggregates form stacks of discoid micelles rather than multilamellar vesicles or inverted hexagonal arrays as previously inferred from indirect observations. The distance between striations within the filaments varies from 4.2 to 5.4 nm and the diameter of the filaments depends on the dehydrated ionic radius of the divalent cation, with average diameters of 19, 12, and 10 nm for filaments formed by Mg2+, Ca2+, and Ba2+, respectively. The structure of the divalent cation-induced aggregates can be altered by PIP2 binding proteins. Gelsolin and the microtubule associated protein tau both affect the formation of aggregates, indicating that tau acts as a PIP2 binding protein in a manner similar to gelsolin. In contrast, another PIP2 binding protein, profilin, does not modify the aggregates. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:9284311
Athow, A C; Filipe, M I; Drake, D P
Three patients with hyperganglionosis are reported in whom an initial diagnosis of Hirschsprung's disease was suspected. In one patient there was a classic presentation with constipation, in another Hirschsprung's disease coexisted, and in the third the initial inadequate suction rectal biopsy specimen was suggestive of Hirschsprung's disease on acetylcholinesterase staining. Evidence of hypertrophy and hyperplasia of the intermuscular and submucosal plexuses on a full thickness bowel biopsy specimen was used to confirm the diagnosis of hyperganglionosis, suggested by the characteristic demonstration of moderate increase in the number of acetylcholinesterase stained nerve fibres in the lamina propria mucosae on rectal biopsy. Surgical management was guided by clinical signs. Two patients had colonic resections; the third had temporary stomal diversion. Hyperganglionosis is rarer than Hirschsprung's disease but is known to mimic it. We suggest full thickness bowel specimens are needed to confirm the diagnosis and that inadequate rectal suction biopsies must be interpreted with caution. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1755642
Khodadad, J K; Waugh, R E; Podolski, J L; Josephs, R; Steck, T L
The role of the membrane skeleton in determining the shape of the human red cell was probed by weakening it in situ with urea, a membrane-permeable perturbant of spectrin. Urea by itself did not alter the biconcave disk shape of the red cell; however, above threshold conditions (1.5 M, 37 degrees C, 10 min), it caused an 18% reduction in the membrane elastic shear modulus. It also potentiated the spiculation of cells by lysophosphatidylcholine. These findings suggest that the contour of the resting cell is not normally dependent on the elasticity of or tension in the membrane skeleton. Rather, the elasticity of the skeleton stabilizes membranes against deformation. Urea treatment also caused the projections induced both by micropipette aspiration and by lysophosphatidylcholine to become irreversible. Furthermore, urea converted the axisymmetric conical spicules induced by lysophosphatidylcholine into irregular, curved and knobby spicules; i.e., echinocytosis became acanthocytosis. Unlike controls, the ghosts and membrane skeletons obtained from urea-generated acanthocytes were imprinted with spicules. These data suggest that perturbing interprotein associations with urea in situ allowed the skeleton to evolve plastically to accommodate the contours imposed upon it by the overlying membrane. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:8789122
Hargis, A. M.; Prieur, D. J.; Haupt, K. H.; Collier, L. L.; Evermann, J. F.; Ladiges, W. C.
Postmortem evaluations were performed on 20 juvenile to young adult collie and collie-Labrador retriever crossbred dogs with dermatomyositis and 10 neonatal collies. Cutaneous, muscular, and vascular lesions were present in the juvenile and adult dogs and were most severe in areas of the head and distal extremities. In more severely affected dogs, lesions were more generalized, including myositis of esophageal muscle and arteritis of skin, muscle, bladder, and spermatic cord. Although viruses were not isolated from muscle, crystalline viral-like structures were present in cytoplasm of endothelial cells within skeletal muscle. The dogs with dermatitis and myositis consistently had lymphoid hyperplasia, especially of peripheral lymph nodes. More severely affected dogs were smaller than less severely affected littermates, and the more severely affected males had reduced weight of testicles and prostate glands, compared with body weight. The reduced weight of genital organs correlated positively with reduced fertility. A few lymphoid aggregates were present in or around thyroid glands of 6 of the 20 dogs. There was no histologic evidence of glomerular disease in any of the dogs. The neonatal collies had no evidence of dermatomyositis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:3717301
Zhang, Y; Sheng, S; Shao, Z
It has long been recognized that one of the major limitations in biological atomic force microscopy (AFM) is the softness of most biological samples, which are easily deformed or damaged by the AFM tip, because of the high pressure in the contact area, especially from the very sharp tips required for high resolution. Another is the molecular motion present at room temperature due to thermal fluctuation. Using an AFM operated in liquid nitrogen vapor (cryo-AFM), we demonstrate that cryo-AFM can be applied to a large variety of biological samples, from immunoglobulins to DNA to cell surfaces. The resolution achieved with cryo-AFM is much improved when compared with AFM at room temperature with similar specimens, and is comparable to that of cryo-electron microscopy on randomly oriented macromolecules. We will also discuss the technical problems that remain to be solved for achieving even higher resolution with cryo-AFM and other possible applications of this novel technique. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:8889193
Sowden, J; Putt, W; Morrison, K; Beddington, R; Edwards, Y
DEAD box proteins share several highly conserved motifs including the characteristic Asp-Glu-Ala-Asp (D-E-A-D in the amino acid single-letter code) motif and have established or putative ATP-dependent RNA helicase activity. These proteins are implicated in a range of cellular processes that involve regulation of RNA function, including translation initiation, RNA splicing and ribosome assembly. Here we describe the isolation and characterization of an embryonic RNA helicase gene, ERH, which maps to mouse chromosome 1 and encodes a new member of the DEAD box family of proteins. The predicted ERH protein shows high sequence similarity to the testes-specific mouse PL10 and to the maternally acting Xenopus An3 helicase proteins. The ERH expression profile is similar, to that of An3, which localizes to the animal hemisphere of oocytes and is abundantly expressed in the embryo. ERH is expressed in oocytes and is a ubiquitous mRNA in the 9 days-post-conception embryo, and at later stages of development shows a more restricted pattern of expression in brain and kidney. The similarities in sequence and in expression profile suggest that ERH is the murine equivalent of the Xenopus An3 gene, and we propose that ERH plays a role in translational activation of mRNA in the oocyte and early embryo. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8948440
Takeshita, S; Kikuno, R; Tezuka, K; Amann, E
A cDNA library prepared from the mouse osteoblastic cell line MC3T3-E1 was screened for the presence of specifically expressed genes by employing a combined subtraction hybridization/differential screening approach. A cDNA was identified and sequenced which encodes a protein designated osteoblast-specific factor 2 (OSF-2) comprising 811 amino acids. OSF-2 has a typical signal sequence, followed by a cysteine-rich domain, a fourfold repeated domain and a C-terminal domain. The protein lacks a typical transmembrane region. The fourfold repeated domain of OSF-2 shows homology with the insect protein fasciclin I. RNA analyses revealed that OSF-2 is expressed in bone and to a lesser extent in lung, but not in other tissues. Mouse OSF-2 cDNA was subsequently used as a probe to clone the human counterpart. Mouse and human OSF-2 show a high amino acid sequence conservation except for the signal sequence and two regions in the C-terminal domain in which 'in-frame' insertions or deletions are observed, implying alternative splicing events. On the basis of the amino acid sequence homology with fasciclin I, we suggest that OSF-2 functions as a homophilic adhesion molecule in bone formation. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:8363580
Pancreatic carcinogenesis in the Syrian hamster, induced by beta-oxidized derivatives of N-nitroso-di-n-propylamine, constitutes a valuable model of human cancer of the exocrine pancreas. In both species the majority of tumors are adenocarcinomas: superficially, on the basis of their histological appearance, these appear to be ductal in origin. However, sequential analysis, by electron microscopy, of the development of pancreatic neoplasia in the hamster model indicates that acinar cells may participate in the histogenesis of "ductal" adenomas and carcinomas. Acinar cells appear to undergo changes in differentiation, including pseudoductular transformation, giving rise to a new population of cells that resemble ductular or centroacinar types. This new population may then proliferate to form, first, cystic foci and subsequently cystadenomas and adenocarcinomas. Mucous metaplasia appears to develop at late stages of tumor development. Although the participation of ductular and centroacinar cells in pancreatic carcinogenesis cannot be excluded, very few tumors arise from the ductal epithelium. It is possible that some human pancreatic adenocarcinomas may also have their origin from dysplastic acinar cells, by analogy with the hamster model: focal acinar dysplasia being common in human pancreatic cancer patients. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. FIGURE 10. FIGURE 11. FIGURE 12. FIGURE 13. FIGURE 14. FIGURE 15. FIGURE 16. FIGURE 17. FIGURE 18. PMID:6383797
Herman, M. M.; Sipe, J. C.; Rubinstein, L. J.; Vandenberg, S. R.; Spence, A. M.; Vraa-Jensen, J.
The electron microscopic features of the stages of divergent neuroepithelial differentiation in the solid implants of a transplantable mouse testicular teratoma (OTT-6050) are presented and compared to the sequential stages of cytogenesis that have been described in the developing avian and mammalian central nervous system. Primitive neuroepithelial tumor cells showed the features of undifferentiated multipotential matrix (or ventricular) cells of the neural tube. They formed primitive medullary rosettes, from which various transitions were traced to more differentiated, cilia-containing ependymoblastomatous rosettes; the transitional features included increased granular endoplasmic reticulum and microvilli formation. Glial differentiation was characterized by the presence of mature ependymal rosettes and of astrocytes containing glial filaments. Neuronal differentiation included the development of synapses and the presence of dense-core vesicles in nerve cell processes. No intermediate cell forms were found that suggested multiple lines of differentiation occurring within a single cell. Images Figure 17 Figure 18 Figure 19 Figure 20 Figure 1 Figure 2 Figure 21 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 PMID:171962
Swartz, D R; Moss, R L; Greaser, M L
Skeletal muscle contraction is regulated by calcium via troponin and tropomyosin and appears to involve cooperative activation of cross-bridge binding to actin. We studied the regulation of fluorescent myosin subfragment 1 (fS1) binding to rigor myofibrils over a wide range of fS1 and calcium levels using highly sensitive imaging techniques. At low calcium and low fS1, the fluorescence was restricted to the actin-myosin overlap region. At high calcium and very low fS1, the fluorescence was still predominantly in the overlap region. The ratio of nonoverlap to overlap fluorescence intensity showed that increases in the fS1 level resulted in a shift in maximum fluorescence from the overlap to the nonoverlap region at both low and high calcium; this transition occurred at lower fS1 levels in myofibrils with high calcium. At a fixed fS1 level, increases in calcium also resulted in a shift in maximum fluorescence from the overlap region to the nonoverlap region. These results suggest that calcium alone does not fully activate the thin filament for rigor S1 binding and that, even at high calcium, the thin filament is not activated along its entire length. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 7 FIGURE 9 FIGURE 11 PMID:8889164
Camussi, G.; Caldwell, P. R.; Andres, G.; Brentjens, J. R.
The effect of repeated interactions of antibodies with cell surface antigens have been examined in in vitro, but not in in vivo systems. In this study are described the results of multiple antibody-cell surface antigen interactions in vivo. Rabbits were given repeated intravenous injections of goat antibodies to angiotensin converting enzyme (ACE), an antigen expressed on the surface of lung endothelial cells. For prevention of anaphylactic reactions, which would have been induced by multiple injections of heterologous immune or nonimmune IgG, the rabbits were made neonatally tolerant to goat IgG. Divalent immune IgG given daily for 21 days induced chronic antigenic modulation (antigen disappearance) with resistance to antibody-mediated inflammatory lesions. The rabbits, however, developed degenerative changes of alveolar endothelial and epithelial cells. Administration of immune IgG every other day for 43 days allowed partial reexpression of ACE and was associated with intravascular, but not interstitial, inflammatory changes. In contrast, repeated administration of monovalent immune Fab did not induce antigenic modulation but caused severe, lethal, interstitial pneumonitis. Thus, in this experimental model the development of acute interstitial inflammatory changes correlates with persistence of antigen and is abrogated by disappearance of antigen induced by divalent antibodies. Further, repeated endothelial antigen antibody interactions fail to induce chronic inflammatory or sclerosing lung lesions. Images Figure 5 Figure 6 Figure 11 Figure 12 Figure 13 Figure 1 Figure 2 Figure 3 Figure 4 Figure 7 Figure 7 Figure 9 Figure 10 PMID:3034065
Waisman, J.; Mwasi, L. M.; Bluestone, R.; Klinenberg, J. R.
Hyperuricemia and uricosuria were induced in rats fed uric acid and oxonic acid. Kidneys then were studied by light and electron microscopy. After 1 day of hyperuricemia, animals had deposits of uric acid and urate crystals within collecting tubules of the renal papillae, and tubular cells were altered. By 10 days, there was an exudative response with further injury to epithelium. Clear spaces within lumens, epithelium, and neutrophils suggested the presence of crystals; however, there was no direct ultrastructural evidence that neutrophils or epithelial cells ingested crystals and suffered injury. Presumably, crystals readily seen in frozen, unfixed tissue were lost during preparation for electron microscopy. Nonetheless, the ultrastructural findings indicated that hyperuricemic nephropathy was initiated in a fashion analogous to urate arthropathy. Urate crystals formed within collecting tubules, epithelial cells were altered, and most likely there was chemotaxis of neutrophils which underwent degranulation and vacuolation followed by lysis freeing any ingested urate. Release of ingested crystals plus precipitation of new crystals both might serve to sustain the nephritis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:1190294
Konrad, H; Merriam, J C; Jones, I S
PURPOSE: This paper describes the surgical rehabilitation of a child with craniofacial anomalies, unilateral syndactyly, and partial unilateral cryptophthalmos associated with inferior colobomata of the iris and optic nerve and agenesis of the inferior rectus and inferior oblique muscles. The clinical presentation of cryptophthalmos is described. METHODS: The medical literature since the original description of cryptophthalmos in 1872 was reviewed to define patterns of inheritance and the incidence of associated anomalies. RESULTS: Including this patient, 149 case reports of cryptophthalmos were identified. In two families transmission from parent to child suggests dominant inheritance. None of the five dominant cases had any other anomalies, and all had bilateral complete cryptophthalmos. The incidence of cryptophthalmos in the remaining families is consistent with autosomal recessive inheritance. This group includes patients with bilateral, unilateral, and partial cryptophthalmos. Other anomalies are common, including those of the ear and nose, limbs, genitourinary system, and mouth and palate. Mortality in the perinatal period is associated with renal agenesis, laryngeal atresia, and pulmonary hypoplasia. CONCLUSIONS: Cryptophthalmos is a rare congenital anomaly with two patterns of inheritance. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 PMID:8719680
Cammoun, Driss; Davis, Kathleen A.; Hendee, William R.
Magnetic resonance imaging has far-reaching real and possible clinical applications. Its usefulness has been best explored and realized in the central nervous system, especially the posterior fossa and brain stem, where most abnormalities are better identified than with computed tomography. Its lack of ionizing radiation and extreme sensitivity to normal and abnormal patterns of myelination make magnetic resonance imaging advantageous for diagnosing many neonatal and pediatric abnormalities. New, reliable cardiac gating techniques open the way for promising studies of cardiac anatomy and function. The ability to image directly in three orthogonal planes gives us new insight into staging and follow-up of pelvic tumors and other pelvic abnormalities. Exquisite soft tissue contrast, far above that attainable by other imaging modalities, has made possible the early diagnosis of traumatic ligamentous knee injury, avascular necrosis of the hip and diagnosis, treatment planning and follow-up of musculoskeletal neoplasms. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9. PMID:3911592
Burton, K; Huxley, A F
The most widely used technique for dynamic estimates of sarcomere length in muscle is laser light diffraction. We have identified conditions under which artifactual oscillations can arise in apparent sarcomere length measured by this technique and report methods to reduce the effect. Altringham et al. (1984) first reported that the diffraction angle can exhibit one cycle of oscillation for each sarcomere length displacement of the illuminated portion of the fiber. We find that the amplitude of similar oscillations is strongly dependent on the intensity of light scattered from objects near the fiber and on the spacing between fiber and scatterer. The oscillations can be eliminated by minimizing scattered light and positioning the fiber a few millimeters from sources of scattering. A theoretical description shows that oscillations of this kind are expected from interference of scattered and diffracted light. Interference fringes were observed along the meridian of the pattern, and these moved during translation of either a fiber or a grating. The movement of fringes across the diffraction order shifts the centroid back and forth and, when associated with steady shortening, can give rise to "steps" and "pauses" in apparent striation spacing. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 PMID:7647247
Maggio-Price, L.; Russell, R.; Wolf, N. S.; Alpers, C. E.; Engel, D.
A colony of mice with congenital hemolytic anemia, sphha/sphha, were evaluated over a 3-year period. Prominent findings included decreased survivability, reticulocytosis, increased peripheral blood leukocytes, extramedullary hematopoiesis in liver and spleen, lymphoid hyperplasia and membranoproliferative glomerulonephritis. Older (12 to 21 months) anemic animals had elevated serum levels of IgG1 and IgA. There was deposition of C3, IgG, IgM, and IgA in renal glomeruli of both control and anemic mice, but deposition of IgM and IgA was more prominent and widely distributed in anemic animals and correlated with mesangial expansion and the presence of electron dense deposits in the mesangium and in glomerular capillary walls. Prominent renal tubular hemosiderosis was noted in young and old anemic mice. The relation between the hemolytic anemia and glomerular disease is unclear but these mice may be an animal model useful for exploration of changes attendant with chronic hemolysis and evaluation of renal disease that accompanies hemolytic anemia. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:3414779
Powell, J J; Ainley, C C; Harvey, R S; Mason, I M; Kendall, M D; Sankey, E A; Dhillon, A P; Thompson, R P
Macrophages at the base of human gut associated lymphoid tissue (GALT), become loaded early in life with dark granular pigment that is rich in aluminium, silicon, and titanium. The molecular characteristics, intracellular distribution, and source of this pigment is described. Laser scanning and electron microscopy showed that pigmented macrophages were often closely related to collagen fibres and plasma cells in GALT of both small and large intestine and contained numerous phagolysosomes, previously described as granules, that are rich in electron dense submicron sized particles. Morphological assessment, x ray microanalysis, and image electron energy loss spectroscopy showed three distinct types of microparticle: type I - spheres of titanium dioxide, 100-200 nm diameter, characterised as the synthetic food-additive polymorph anatase; type II - aluminosilicates, < 100-400 nm in length, generally of flaky appearance, often with adsorbed surface iron, and mostly characteristic of the natural clay mineral kaolinite; and type III - mixed environmental silicates without aluminium, 100-700 nm in length and of variable morphology. Thus, this cellular pigment that is partly derived from food additives and partly from the environment is composed of inert inorganic microparticles and loaded into phagolysosomes of macrophages within the GALT of all human subjects. These observations suggest that the pathogenicity of this pigment should be further investigated since, in susceptible individuals, the same intracellular distribution of these three types of submicron particle causes chronic latent granulomatous inflammation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 PMID:8675092
Guyton, J. R.; Klemp, K. F.
Abundant extracellular lipid deposits are associated with cell necrosis and tissue weakening in the core region of human atherosclerotic fibrous plaques. The ultrastructural morphology of the core region, previously undefined because of lipid extraction artifacts, was studied with the aid of new osmium-thiocarbohydrazide-osmium and osmium-tannic acid-paraphenylenediamine sequences for tissue processing. Small droplets of neutral lipid (30 to 400 nm profile diameter) and lipid vesicles with aqueous centers accounted for more than 90% of the area occupied by lipid-rich structures in the core region. No foam cells were present. Cholesterol crystals, lipid droplets of a size similar to those in foam cells (0.4 to 6 mu), and larger neutral lipid deposits (greater than 6 mu) together occupied less than 10% of the total area of lipid structures. Abundant lipid vesicles were associated with the nearby presence of cholesterol crystals, whereas small lipid droplets were predominant in areas without crystals. Many droplets had surface defects in the form of pits and vesicular blebs. These morphologic findings are explained most concisely by postulating direct accumulation of extracellular lipid from interstitial lipoproteins as a major process in core region formation. Moreover, a dynamic state of ongoing physical/metabolic transformation of extracellular lipid deposits is suggested. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 Figure 8 Figure 9 PMID:2646938
Hermann, M.; Bobek-Billewicz, B.; Sloniewski, P.
The purpose of this study was to evaluate the magnetic resonance anatomy of the cavernous sinus. Heavily T2-weighted submillimetric sequence in sagittal, coronal, and axial planes was performed in 16 healthy patients. The sequence provides high contrast between fluid and other structures of the cavernous sinus. High signal intensity of the venous spaces of the cavernous sinus provides a kind of a background for internal carotid artery, cranial nerves, and meninges, as well as bony and fibrous structures. The study was performed with the help of an anatomic atlas. Different magnetic resonance (MR) landmarks of the cavernous and parasellar region were introduced and demonstrated. MR images, superior to computer tomography, allow a detailed assessment of the cavernous sinus anatomy. Delineation by magnetic resonance of tiny anatomical structures may help the neurosurgeon trace the exact outline of a tumor and help to plan an adequate strategy if complete resection is attempted. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 8 PMID:17171105
Gershenzon, Jonathan; Maffei, Massimo; Croteau, Rodney
The primary monoterpene accumulated in the glandular trichomes of spearmint (Mentha spicata) is the ketone (−)-carvone which is formed by cyclization of the C10 isoprenoid intermediate geranyl pyrophosphate to the olefin (−)-limonene, hydroxylation to (−)-trans-carveol and subsequent dehydrogenation. Selective extraction of the contents of the glandular trichomes indicated that essentially all of the cyclase and hydroxylase activities resided in these structures, whereas only about 30% of the carveol dehydrogenase was located here with the remainder located in the rest of the leaf. This distribution of carveol dehydrogenase activity was confirmed by histochemical methods. Electrophoretic analysis of the partially purified carveol dehydrogenase from extracts of both the glands and the leaves following gland removal indicated the presence of a unique carveol dehydrogenase species in the glandular trichomes, suggesting that the other dehydrogenase found throughout the leaf probably utilizes carveol only as an adventitious substrate. These results demonstrate that carvone biosynthesis takes place exclusively in the glandular trichomes in which this natural product accumulates. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:16666709
Cattoretti, G.; Villa, A.; Vezzoni, P.; Giardini, R.; Lombardi, L.; Rilke, F.
Ten cases of malignant histiocytosis (MH) were evaluated for clinical and histopathologic features, phenotype, and rearrangement of T cell receptor (TCR) beta, gamma, and alpha and immunoglobulin (Ig) genes (7/10). All cases were HLA-DR+ and CD30-positive. Four cases had molecular evidence of T cell lineage such as TCR beta, gamma, and alpha rearrangements, and one additional case synthesized the cytoplasmic TCR beta chain. The remaining five cases did not show unequivocal T, B, natural killer (NK) cell, or macrophagic origin, and three of them had germline TCR and Ig genes. Ultrastructural analysis was not helpful for the definition of the cell lineage. Most myelomonocytic markers (MAC387, CD13, CD14, CD64, CD68) were either negative on the MH cells or were expressed on cells with rearranged TCR gene. Precursor (CD34, CD7) and NK (CD16, CD56, and CD57) cell markers were not found. The lineage of a number of cases of MH remains unresolved. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:2349962
Hineline, Philip N.
With their origins in scientific validation, behavior-analytic applications have understandably been developed with an engineering rather than a crafting orientation. Nevertheless, traditions of craftsmanship can be instructive for devising aesthetically pleasing arrangements—arrangements that people will try, and having tried, will choose to continue living with. Pye (1968) provides suggestions for this, particularly through his distinctions between workmanship of risk versus workmanship of certainty, and the mating of functional precision with effective or otherwise pleasing variability. Close examination of woodworking tools as well as antique machines offers instructive analogues that show, for instance, that misplaced precision can be dysfunctional when precision is not essential to a design. Variability should be allowed or even encouraged. Thus, in the design of behavioral contingencies as well as of practical or purely aesthetic objects, “precise versus variable” is not necessarily a distinction between good and bad. More generally, behavior analysts would do well to look beyond their technical experience for ways to improve the aesthetics of contingency design while continuing to understand the resulting innovations in relation to behavior-analytic principles. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9 PMID:22478437
Winnard, A V; Mendell, J R; Prior, T W; Florence, J; Burghes, A H
Duchenne muscular dystrophy (DMD) patients with mutations that disrupt the translational reading frame produce little or no dystrophin. Two exceptions are the deletion of exons 3-7 and the occurrence of rare dystrophin-positive fibers (revertant fibers) in muscle of DMD patients. Antibodies directed against the amino-terminus and the 5' end of exon 8 did not detect dystrophin in muscle from patients who have a deletion of exons 3-7. However, in all cases, dystrophin was detected with an antibody directed against the 3' end of exon 8. The most likely method of dystrophin production in these cases is initiation at a new start codon in exon 8. We also studied two patients who have revertant fibers: one had an inherited duplication of exons 5-7, which, on immunostaining, showed two types of revertant fibers; and the second patient had a 2-bp nonsense mutation in exon 51, which creates a cryptic splice site. An in-frame mRNA that uses this splice site in exon 51 was detected. Immunostaining demonstrated the presence of the 3' end of exon 51, which is in agreement with the use of this mRNA in revertant fibers. The most likely method of dystrophin production in these fibers is a second mutation that restores the reading frame. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7825572
Leadbetter, Wyland F.
From review of recent information relative to calculus formation in the kidney, the conclusion reached that we do not yet understand, despite much effort, the basic physicochemical mechanisms involved. Since this is so, it has seemed best to the author for the present to rely, in treating patients with renal stones, on simple therapeutic concepts, which, if carefully and conscientiously applied, produce good results. The concepts are the elimination of known causes such as parathyroid adenomas and obstructive lesions, elimination or at least treatment of infections, diminution of urinary components which form the basis of calculi by limiting the oral intake or absorption from the gastrointestinal tract and maintenance of a dilute urine of desired pH. A plan for preoperative study is suggested to allow planned therapy. Indications for operative removal of calculi as well as some points of technique are discussed. It is emphasized that surgical removal of a calculus is but an incident in the care of patients with calculi and that treatment during the postoperative period and followup therapy is most important if success is to be achieved. Reports of cases to illustrate the application of these concepts are presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 12Figure 13Figure 14Figure 15Figure 16 PMID:13523394
Kuzela, D. C.; Huffer, W. E.; Conger, J. D.; Winter, S. D.; Hammond, W. S.
Autopsy protocols and microscopic slides of 56 dialyzed and 18 nondialyzed chronically uremic patients were reviewed to assess the presence, extent, and severity of extraosseous soft tissue calcification. Calcification was identified in 79% of the dialysis patients and 44% of the nondialysis patients (P iss less than .025). Soft tissue calcification most frequently involved the heart, lungs, stomach, and kidneys. Lesions were severe in 36% of the dialysis patients and, when strategically located within the myocardium, were life-threatening. The deaths of 6 dialysis patients were attributed to severe calcification of the cardiac conduction system and/or myocardium. The presence and severity of soft tissue calcification was not related to duration of dialysis, patients' age, degree of parathyroid gland hyperplasia, radiographic evidence of soft tissue calcification, serum calcium and phosphate levels, Ca X P products, or type or severity of metabolic bone disease. Images Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 11 Figure 12 Figure 3 Figure 4 Figure 5 Figure 6 PMID:836675
In 1996, public outcry over shortened hospital stays for new mothers and their infants led to the passage of a federal law banning "drive-through deliveries." This recent round of brief postpartum stays is not unprecedented. During World War II, a baby boom overwhelmed maternity facilities in American hospitals. Hospital births became more popular and accessible as the Emergency Maternal and Infant Care program subsidized obstetric care for servicemen's wives. Although protocols before the war had called for prolonged bed rest in the puerperium, medical theory was quickly revised as crowded hospitals were forced to discharge mothers after 24 hours. To compensate for short inpatient stays, community-based services such as visiting nursing care, postnatal homes, and prenatal classes evolved to support new mothers. Fueled by rhetoric that identified maternal-child health as a critical factor in military morale, postpartum care during the war years remained comprehensive despite short hospital stays. The wartime experience offers a model of alternatives to legislation for ensuring adequate care of postpartum women. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:10191809
Peters, D. N.; Steinberg, H.; Anderson, W. I.; Hornbuckle, W. E.; Cote, P. J.; Gerin, J. L.; Lewis, R. M.; Tennant, B. C.
Retrospective analysis of necropsy findings of 705 woodchucks was performed to determine the prevalence and morphology of immune-mediated glomerulonephritis, its relationship to woodchuck hepatitis virus (WHV) infection, and the presence of major WHV antigens. Twenty-six woodchucks had glomerular lesions. Renal tissue of the 26 animals was evaluated histologically and immunohistochemically for immune-mediated glomerulonephritis. Of these 26 animals, immune-mediated glomerulonephritis was diagnosed in six, all of which were chronic WHV carriers. Membranous glomerulonephritis was identified in three animals, two of which also had mesangial proliferation. Host immunoglobulin was present within the mesangium and along capillary loops in all three. Woodchuck hepatitis virus core antigen (WHcAg) was present along capillary loops of two of these animals, one membranous and one mixed, and in the mesangium of all three. Woodchuck hepatitis virus surface antigen (WHsAg) deposition was similar to WHcAg deposition but was only present along capillaries in those animals with mixed nephritis. The remaining three animals had mesangial proliferation. WHsAg and host immunoglobulin deposition were predominately mesangial; WHcAg was not detected. Transmission electron microscopy showed thickening of the capillary loop basement membranes and subepithelial electron-dense deposits in animal one, and deposits in the mesangium in animal six. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:1632459
Govindarajan, S.; Fields, H. A.; Humphrey, C. D.; Margolis, H. S.
A hepatitis B surface antigen (HBsAg) chronic carrier chimpanzee experimentally superinfected with delta virus (DV) developed chronic DV infection. Over a period of 12 months, serologic and biochemical changes were correlated with morphologic abnormalities of the liver. Severe hepatic necrosis and inflammation accompanied the initial acute episode of hepatitis on Day 35 after inoculation, followed by complete resolution of these lesions over the next 3 months. A second episode of hepatitis occurred on Day 145, and severe necrosis and inflammation recurred along with the reappearance of delta antigen in the hepatocytes. Delta antigen persisted in the liver following the second episode of hepatitis and has remained positive throughout the observation period of 1 year. During the initial acute episode, the hepatocytes exhibited foamy cytoplasmic changes resembling microvesicular fat. However, ultrastructural studies of the same cells revealed only vacuolization of the cytoplasm without evidence of fat droplets. The inflammatory infiltrate during both episodes of hepatitis demonstrated a striking predominance of macrophages over lymphocytes. Hepatocyte abnormalities observed by electron microscopy included vacuoles, proliferated endoplasmic reticulum, and tubules similar to those seen in posttransfusion non-A, non-B hepatitis. However, the tubular and reticular abnormalities coincided with delta antigen expression in liver biopsies detected by direct immunoperoxidase staining and abnormal alanine aminotransferase levels in the serum, which suggests a possible causal relationship. Nuclear abnormalities were not seen. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:3511726
Milani, S.; Herbst, H.; Schuppan, D.; Surrenti, C.; Riecken, E. O.; Stein, H.
The authors have determined the cell types producing alpha 1 (I), alpha 2 (I), alpha 1 (III), and alpha 1 (IV) procollagen gene transcripts in adult human liver by in situ hybridization with [35S]-labeled RNA probes. The liver specimens comprised a total of 20 biopsies with normal histology and biopsies with fibrosis or cirrhosis at different clinical stages and of heterogeneous origins. In normal liver, procollagen type I, III, and IV transcripts were detected in stromal and vascular mesenchymal cells of portal tracts and central veins, as well as in some perisinusoidal cells of the lobule. In fibrotic liver, increased levels of these procollagen mRNAs were observed in the same locations, and particularly enhanced in stromal cells of fibrotic septa and portal tracts, as well as in perisinusoidal cells. Expression of alpha 1 (IV) procollagen RNA was additionally found in some vascular endothelial and bile duct epithelial cells. Although previously suggested as the major source of liver collagens, hepatocytes showed no significant procollagen transcript levels in any of our samples. Thus, procollagen synthesis does not appear to be a function of hepatocytes, but rather of mesenchymal, endothelial, and bile duct epithelial cells in adult human liver. These findings may have implications for the development of specifically targeted antifibrotic therapies. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:2372043
Herbst, H.; Wege, T.; Milani, S.; Pellegrini, G.; Orzechowski, H. D.; Bechstein, W. O.; Neuhaus, P.; Gressner, A. M.; Schuppan, D.
The remodeling of extracellular matrix during chronic liver disease may partially be attributed to altered activity of matrix metalloproteinases and their tissue inhibitors (TIMPs). Expression of TIMP-1 and -2 was studied by in situ hybridization combined with immunohistochemistry in rat (acute and chronic carbon tetrachloride intoxication and secondary biliary fibrosis) and human livers and on isolated rat hepatic stellate cells. TIMP-1 and -2 transcripts appeared in rat livers within 1 to 3 hours after intoxication, pointing to a role in the protection against accidental activation of matrix metalloproteinases, and were present at high levels in all fibrotic rat and human livers predominantly in stellate cells. TIMP-2 RNA distribution largely matched with previously reported patterns of matrix metalloproteinase-2 (72-kd gelatinase) expression, suggesting generation of a TIMP-2/matrix metalloproteinase-2 complex (large inhibitor of metalloproteinases). Isolated stellate cells expressed TIMP-1 and -2 RNA. Addition of transforming growth factor-beta 1 enhanced TIMP-1 and matrix metalloproteinase-2 RNA levels in vitro, whereas TIMP-2-specific signals were reduced, likely to result in a stoichiometric excess of matrix-metalloproteinase-2 over TIMP-2. In the context of previous demonstrations of transforming growth factor-beta 1 and matrix metalloproteinase-2 in vivo, these patterns suggest an intrahepatic environment permitting only limited matrix degradation, ultimately resulting in redistribution of extracellular matrix with relative accumulation of collagen type 1. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9137090
Frommel, D.; Crevat, D.; Vitvitsky, L.; Pichoud, C.; Hantz, O.; Chevalier, M.; Grimaud, J. A.; Lindberg, J.; Trépo, C. G.
The natural history of infection with woodchuck hepatitis virus (WHV) has been studied in a colony of 38 Marmota monax. Besides serologic assessment for WHV markers, light-microscopic findings of 61 liver biopsies were correlated with the results of immunofluorescence analysis for nucleocapsid (WHcAg) and surface (WHsAg) antigens. Twenty-four chronic WHsAg carriers all featured signs of continuous viral replication. Two major immunomorphologic patterns were observed in their livers: 1) portal hepatitis in which WHcAg accumulated in the cytoplasm and WHsAg was associated with the hepatocyte membrane and 2) periportal hepatitis in which WHcAg shifted toward nuclear localization and WHsAg became mostly intracytoplasmic. Progression from portal to periportal hepatitis, observed in 7 woodchucks, appeared to be induced by a partial recovery of specific immune reactivity to WHV, insufficient, however, to interrupt WHV replication. Deposits of WHsAg and immunoglobulins were present in the kidney and spleen of animals with severe hepatitis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6324594
Arthropods capable of penetrating human skin often cause severe local and systemic reactions. Local reactions suggest delayed hypersensitivity while systemic symptoms resemble more the anaphylactic shock in animals. The nature of the antigen remains obscure but predominant evidence suggests its presence throughout the entire organism. Positive history of hypersensitivity to insect injectants was obtained in approximately 20 per cent of persons in the course of routine interviews of 1,078 patients. Repeated bites and stings at long or irregular intervals often induce a state of hypersensitivity, while repeated regular injections of extracts of these insects at shorter intervals may greatly reduce the hypersensitivity. The clinical evidence of allergic sensitivity to insect bites and stings cannot be readily confirmed by skin testing or by other immunological procedures. The history and the character of the lesions as well as certain entomological knowledge of the habits of the insects offer a better basis for specific diagnosis. Treatment with extracts of the whole offending insect generally provides good results but the protection afforded by such treatment varies in degree and duration. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:14485406
Fairweather, D; Lawson, C M; Chapman, A J; Brown, C M; Booth, T W; Papadimitriou, J M; Shellam, G R
The laboratory-adapted K181 strain of murine cytomegalovirus (MCMV) induces both acute and chronic myocarditis, associated with autoantibodies to cardiac myosin, in susceptible BALB/c mice. However, the K181 MCMV strain has been maintained in the laboratory for many years and may not resemble naturally occurring strains of MCMV in its ability to induce myocarditis. Accordingly, six different isolates of MCMV from wild Mus domesticus were compared with K181 MCMV for their ability to induce myocarditis and autoantibodies to cardiac myosin in BALB/c mice. These isolates were shown to induce acute myocarditis similar to K181 MCMV, with associated focal and diffuse myocardial inflammation. However, the levels of myocarditis induced by the wild isolates during the chronic phase of the disease (days 32-56 post-infection) were low in contrast to the K181 strain. Interestingly, 30% of wild-trapped mice showed histological evidence of myocarditis and all were sero-positive to MCMV. Sera from BALB/c mice infected with wild MCMV isolates and from wild-trapped mice contained antibodies that cross-reacted with MCMV and cardiac myosin (S2 region). The cross-reactive region of MCMV was found to be a 50,000-55,000 MW viral polypeptide. These findings suggest that molecular mimicry may be involved in the pathogenesis of autoimmune myocarditis following infection with both laboratory and wild MCMV strains. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:9741351
Lloyd, R. V.; Schmidt, K.; Nath, V.
Hyperplastic anterior pituitary glands were produced in female rats by treatment with 10 mg of diethylstilbestrol in Silastic tubing. This led to increased numbers of immunoreactive prolactin cells and increased serum prolactin levels. After 6 weeks of diethylstilbestrol treatment, one group of rats was treated with daily injections of pergolide for 3 weeks. Pergolide produced a significant decrease in pituitary gland weight and in serum prolactin levels but did not change the percentage of prolactin cells significantly, compared with that of control rats. Ultrastructural studies showed a significant increase in the numbers of prolactin secretory granules and numerous large intracellular bodies with associated secretory granules in pituitaries from rats treated with pergolide. In one group of rats in which the diethylstilbestrol was discontinued for 3 weeks after 6 weeks of treatment there was a significant decrease in pituitary gland weight and serum prolactin and a significant decrease in the percentage of prolactin cells, compared with values in the rats treated with diethylstilbestrol for 9 weeks. These results indicate that pergolide causes decreased release of prolactin from secretory granules in anterior pituitary prolactin cells and an increase in the numbers of PRL secretory granules per cell but does not change the percentage of prolactin-producing pituitary cells after 3 weeks of treatment. Images Figure 3 Figure 4 Figure 1 p489-a Figure 2 Figure 5 Figure 6 PMID:4073221
Tsutsumi, V.; Mena-Lopez, R.; Anaya-Velazquez, F.; Martinez-Palomo, A.
The complete sequence of morphologic events during amebic liver abscess formation in the hamster has been studied, from the lodgement of amebas in the hepatic sinusoids to the development of extensive liver necrosis. Following intraportal inoculation of live amebas, the early stages of the lesion (from 1 to 12 hours) were characterized by acute cellular infiltration composed of an increasingly large number of polymorphonuclear leukocytes, which surrounded centrally located trophozoites. Histiocytes and lysed leukocytes were situated on the periphery of the lesions. Hepatocytes close to the early lesions showed degenerative changes which led to necrosis; however, direct contact of liver cells with amebas was very rarely observed. At later stages, the extent of necrosis increased, macrophages and epithelioid cells replaced most leukocytes, and well-organized granulomas developed. Extensive necrosis associated with fused granulomas was present by Day 7. The results suggest that Entamoeba histolytica trophozoites do not produce amebic liver abscesses in hamsters through direct lysis of hepatocytes. Rather, tissue destruction is the result of the accumulation and subsequent lysis of leukocytes and macrophages surrounding the amebas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6385728
Osborn, K. G.; Prahalada, S.; Lowenstine, L. J.; Gardner, M. B.; Maul, D. H.; Henrickson, R. V.
A syndrome of acquired immunodeficiency within a group of outdoor-housed rhesus macaques (Macaca mulatta) with unusually high mortality has been identified at the California Primate Research Center. The cause of death for most of the affected animals included septicemia and/or chronic diarrhea with wasting, often complicated by other problems. In many cases, multiple or unusual infectious agents were isolated or recognized, including cytomegalovirus, Cryptosporidium spp., and Candida albicans. Septicemias due to usually innocuous agents such as Staphylococcus epidermidis and Alcaligenes faecalis were seen. Two animals developed cutaneous fibrosarcomas. Affected animals had generalized lymphadenopathy and splenomegaly, with depletion of T-cell populations, initially follicular hyperplasia followed by depletion, and absence of plasma cells. This spontaneous disease syndrome in nonhuman primates has similarities to acquired immune deficiency syndrome (AIDS) in humans, providing an animal model for the study of the complex factors modulating the immune system. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 PMID:6691418
Anderson, P. G.; Bishop, S. P.; Digerness, S. B.
The purpose of this study was to compare the functional and morphologic changes that occur during ischemic contracture and reperfusion in the normal and hypertrophied heart. Hearts from Sprague-Dawley, spontaneously hypertensive (SHR), and normotensive Wistar-Kyoto rats were evaluated using a modified Langendorff perfusion apparatus. After obtaining control data, hearts were potassium-arrested, made ischemic, and studied at various time points. Regional coronary flow was assessed with the use of radiolabeled microspheres or Microfil dye infusion, and morphologic changes were evaluated by means of light and electron microscopy. Sarcomere length changes and qualitative morphologic changes during global ischemia demonstrate a transmural progression of ischemic damage starting at the endocardium and extending, with time, epicardially. The progression of ischemic changes in hypertrophied hearts of SHRs was similar to that of normal hearts; however, hypertrophied hearts developed ischemic contracture sooner than normal hearts. In addition, the development of contraction band change after ischemic contracture occurred only when hearts were reperfused and was related to the development of no-reflow. Images Figure 4 Figure 5 Figure 2 Figure 3 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:2959155
Perossa, Daniel R; Dziak, Martin; Vernon, Howard T; Hayashita, Kaye
The purpose of this study was to investigate the intrarater reliability of manual muscle assessment of the hip and shoulder using a modified sphygmomanometer. In addition, it was intended to establish a preliminary database of values from normal, healthy male and female volunteers. Eighty subjects participated in the test sessions, 40 males and 40 females between the ages of 19-22. Forty subjects participated in each of the hip and shoulder test sessions. Each examiner tested different paired movements on the subjects in one single session for the two separate joints. The tested movements consisted of hip extension, flexion and abduction and shoulder abduction, extension, flexion, internal and external rotation. All movements were tested by the patient-initiated method. Each movement was repeated twice, with a 30-35 second rest interval between the trials. The results showed that the intratester reliability coefficients for the hip ranged from 0.94-0.97, while, for the shoulder, the range was 0.86-0.97. Norms are expressed as mean (SD) values. These data conformed to previously established expectations, in that side-to-side differences were less than 10% and test values for males were larger than females in all tests. It was concluded that manual muscle assessment using a modified sphygmomanometer has acceptable intra-examiner reliability for the hip and shoulder when using the patient-initiated method. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8
Wencel-Drake, J. D.; Plow, E. F.; Zimmerman, T. S.; Painter, R. G.; Ginsberg, M. H.
The distribution and transport of thrombospondin (TSP), fibrinogen (Fbg), fibronectin (Fn), and Factor VIII-related antigen (VIII:RAg) in resting and thrombin-stimulated platelets was investigated by immunofluorescence microscopy. In resting intact cells, little surface staining was seen for these proteins. In permeable resting cells, punctate staining similar to that reported for platelet factor 4 was observed. Double-label immunofluorescence staining for Fbg and either beta-thromboglobulin (beta TG), TSP, or Fn demonstrated co-localization, indicating their presence in the same intracellular structures. VIII:RAg showed general co-localization; however, the staining was finer, suggesting a possible differential intragranular localization. Thrombin stimulation induced the appearance of larger (approximately 0.5 mu) immunofluorescent masses of these proteins. In thrombin-stimulated cells, co-localization of all proteins in these masses was observed by double label immunofluorescence. Thus, TSP, Fbg, Fn, and beta TG are localized in the same structure in resting cells. Thrombin stimulates formation of common larger masses of these proteins prior to their release, suggesting that they reach the cell surface through a common intermediate. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6232852
Grover, J; Roughley, P J
The chondrocytes in human articular cartilage from subjects of all ages express mRNAs for both of the aggregating proteoglycans aggrecan and versican, although the level of expression of versican mRNA is much lower than that of aggrecan mRNA. Aggrecan shows alternative splicing of the epidermal growth factor (EGF)-like domain within its C-terminal globular region, but there is no evidence for a major difference in situ in the relative expression of this domain with age. At all ages studied from birth to the mature adult, a greater proportion of transcripts lacked the EGF domain. The relative proportions of the two transcripts did not change upon culture and passage of isolated chondrocytes. In contrast, the neighbouring complement regulatory protein (CRP)-like domain was predominantly expressed irrespective of age, but cell culture did result in variation of the splicing of this domain. Versican possesses two EGF-like domains and one CRP-like domain, but at all ages the three domains were predominantly present in all transcripts. This situation persisted upon culture and passage of the chondrocytes. Thus, unlike aggrecan, the versican expressed by human articular cartilage does not appear to undergo alternative splicing of its C-terminal globular region, either in cartilage in situ or in chondrocytes in culture. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8484718
Colombo, M. P.; Lombardi, L.; Melani, C.; Parenza, M.; Baroni, C.; Ruco, L.; Stoppacciaro, A.
C-26 colon adenocarcinoma cells transduced with the granulocyte colony-stimulating factor (G-CSF) gene form large tumors when injected into sublethally irradiated mice. These tumors regress when leukocyte function is reconstituted. Electron microscopy and immunocytochemical analysis of regressing C-26/G-CSF nodules indicates that tumor destruction is due mainly to hypoxia resulting from the functional loss of tumor vasculature and is only marginally due to direct cytolysis. Desegregation of basal lamina, cell swelling, and loss of junctions characterized the vessels within regressing tumors. Tumor cells were necrotic or filled with lipid vacuoles regardless of the distance from nearby vessels. Damage of tumor vasculature was dependent on the infiltrating leukocytes and the cytotoxic cytokines they produced. Locally produced interleukin-1 and tumor necrosis factor-alpha (TNF-alpha) induced vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin on tumor vessels. Treatment with monoclonal antibodies to interferon-gamma (IFN-gamma) or TNF-alpha blocked tumor regression by inhibiting VCAM-1 and E-selectin expression on tumor-associated endothelial cells resulting in a reduced number of infiltrating leukocytes. Thus, C-26/G-CSF tumor regression presents features typical of hemorrhagic necrosis that occurs through the cytokines produced by infiltrating leukocytes in response to G-CSF. Images Figure 1 p477-a Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8579110
Bender, B. L.; Jaffe, R.; Carlin, B.; Chung, A. E.
Entactin is a sulfated glycoprotein in the extracellular basement membrane like matrix produced by M1536-B3 cells, a mouse endodermal line derived from an embryonal carcinoma. It has a molecular weight of 158,000 and is chemically and immunologically distinguishable from GP-2 (laminin) and fibronectin. Antibodies produced against entactin and GP-2 react with subepithelial and vascular basement membranes in rat lung, liver, spleen, and kidney and mouse placenta and kidney when examined by light microscopy. Both antibodies yield staining around the marginal sinus of the white pulp of the spleen. Antientactin reacts with basement membrane and mesangium in rat glomeruli, and anti-GP2 does not. Ultrastructurally, staining in kidneys is strongest at epithelial or endothelial cell membranes bordering basement membranes, with only moderate staining of the basement membrane proper. Intracellular staining is not present. The location of entactin suggests that it has a role in the interaction of cells with extracellular matrix, possibly in adhesion. Lack of intracellular staining suggests that the tissues studied are not actively producing entactin or GP-2 and that these substances may be fairly stable in adult organisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:6165248
Calabrese, K. S.; Lagrange, P. H.; da Costa, S. C.
Naturally immunocompromised athymic mice, neonatal mice and adult outbred OFI mice treated with the immunosuppressive agents cyclophosphamide (CY), dexamethasone (DM) and indomethacin (IM) were infected with trypomastigotes of Trypanosoma cruzi Y and CL strains. 10(4) parasites were used, except in the case of IM treatment, where mice received 10(3) trypomastigotes in one group and 10(5) in another. The course of parasitaemia, tissue distribution of amastigotes and time of mortality were compared with an infected thymus intact control group. Neonate and indomethacin treated mice presented the same pattern of parasitaemia. Death occurred as early as 9-10 days after infection. A single dose of CY 200 mg/kg given 5 days after infection enhanced the parasitaemia and increased the number of parasites in the tissues. All groups were similar in terms of colonization of the endocrine system by parasites and the adrenals showed the highest density of amastigotes nests. The thyroid gland (analysed only in neonates) showed intense amastigote accumulation. Colonization of the ovary was observed with amastigotes in both the theca interna and in the stroma. The testes (also examined only in the neonate) showed that the interstitial cells, the tunica albuginea of the seminiferous tubules and the loose connective tissue were infected. Athymic nude mice showed the most intense parasite colonization of the islets of Langerhans. Images Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7734334
Harris, G J
The clinical course of SPA of the orbit is associated with the age of the patient. That association might be explained through a series of intermediate relationships: the clinical course correlates with the bacterial constituency, the bacterial constituency is related to physiologic derangement within the sinuses, the physiologic derangement may vary with the degree of obstruction of the sinus ostia, and the ostial caliber relative to the volume of the cavity that must be drained decreases with patient age into late adolescence. The controversy between pediatricians and surgeons over the appropriate indications for drainage might be resolved with the acknowledgement that each side is correct on the basis of the patient populations treated. It is hoped that recognition of the age-related variations in SPA will permit a more systematic approach to the management of this complex infectious disease. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 FIGURE 14 FIGURE 15 FIGURE 16 FIGURE 17 FIGURE 18 FIGURE 19 FIGURE 20 FIGURE 21 FIGURE 22 FIGURE 23 FIGURE 24 FIGURE 25 FIGURE 26 FIGURE 27 PMID:8140703
Coltoff-Schiller, B.; Goldfischer, S.
Glycosaminoglycans (GAGs) have been implicated in the pathogenesis of sclerotic vascular disease. The localization of GAGs in the rat aorta was examined by two different ultrastructural cytochemical approaches. These procedures are believed to demonstrate 1) anionic sites, with fixatives that contain either toluidine blue or ruthenium red, both cationic dyes, and 2) polysaccharides, proteoglycans, and glycoproteins, with an osmium--ferrocyanide mixture that binds to vicinal diols. Both procedures stain a network of insoluble, 2--8-nm filaments that bridge collagen fibers, elastin, basement membranes, and plasma membranes. These structures resist digestion with chondroitinase ABC and appear to be identical to the filaments that have previously been demonstrated with ruthenium red. Focal 6--12-nm densities are present where filaments intersect. However, the large granules that are made visible with ruthenium red are not seen in toluidine blue or osmium--ferrocyanide preparations. A soluble and relatively amorphous component surrounds the tightly packed bundles of collagen in the media and is preserved and stained by toluidine blue and osmium--ferrocyanide mixtures. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:6172040
Allen, Gregory J.; Burnett, Keith R.; Vaziri, Nosratola D.; Friedenberg, Richard M.
Hemodialysis access fistulae or grafts are subject to a variety of complications, including thrombosis, stenoses, and aneurysm or pseudoaneurysm formation. The usual radiologic methods to evaluate these problems consist of retrograde venous angiography or standard femoral or brachial arteriography. Both are invasive, and may traumatize the artery or graft. Six patients with internal blood access were studied using digital subtraction angiography; five using a central venous injection and one with direct graft injection. Preliminary results indicate that intravenous digital subtraction angiography (IV-DSA) can depict the anatomy of access fistula with adequate spatial resolution. Pathologic entities (stenoses, aneurysms) can be demonstrated, as well as other findings of uncertain clinical significance (kinks and webs). In addition, hemodynamic data can be inferred from the near-physiologic sequence of vessel opacification. Methods are in development that will allow determination of absolute blood flow in pertinent vessels via IV-DSA. There were no complications in this small series, and all examinations were performed on outpatients utilizing standard technique. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:3537322
McNutt, N. S.; Fletcher, V.; Conant, M. A.
An aggressive variant of Kaposi's sarcoma (KS) has appeared in young homosexual men with evidence of systemic immunosuppression. The ultrastructure in biopsy specimens from 8 KS cases in young homosexual men has been compared with that in biopsy specimens from 4 KS cases in elderly heterosexuals and with that in biopsy specimens from 23 cases of benign vascular disorders of skin. In all cases of KS the small blood vessels lacked a prominent investment of pericytes and their processes, had a fragmented and often absent basal lamina, had frequent discontinuities in the endothelial lining, and had only a few small junctional densities between endothelial cells. Some clinically aggressive cases of KS also had necrosis of individual endothelial cells and had prominent cytoplasmic processes entrapping individual collagen fibers. The benign disorders lacked these features. These differences in the structure of the small vessels may be of diagnostic value in some early cases of KS. The loss of dendritic pericytes in blood capillaries in KS might relate to the telangiectasia which is a prominent feature of the early lesions of KS. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:6301283
Faraggiana, T.; Churg, J.; Grishman, E.; Strauss, L.; Prado, A.; Bishop, D. F.; Schuchman, E.; Desnick, R. J.
A histochemical study was performed on light- and electron-microscopic level in a case of Fabry's disease. The patient underwent kidney transplantation for renal failure and died of heart failure 6 months later. Patient's tissues were studied at the light- and electron-microscopic levels with various embedding and staining techniques for lipids and carbohydrates. Two peroxidase-labeled lectins (from Ricinus communis and from Bandeiraea simplicifolia) known to have affinity for alpha- and beta-D-galactose, were strongly reactive with the storage material on frozen sections. The ultrahistochemical and extraction tests showed that the typical granules had a variable reactivity and morphologic characteristics in different cells, probably reflecting different composition. A small number of typical deposits were also observed in the transplanted kidney. This is the first reported case of recurrence of the storage disease in the allograft. Of interest was also the fact that the patient's blood inhibited normal alpha-galactosidase activity, suggesting a possible inhibitor-related mechanism in the pathogenesis of the recurrence. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 PMID:6786101
Mortain-Bertrand, Anne; Bennett, John; Falkowski, Paul G.
The marine chlorophyte Dunaliella tertiolecta Butcher responds to a one-step transition from a high growth irradiance level (700 micromoles quanta per square meter per second) to a low growth irradiance level (70 micromoles quanta per square meter per second) by increasing the total amount of light-harvesting chlorophyll (Chl) a/b binding protein associated with photosystem II (LHC II), and by modifying the relative abundance of individual LHC II apoproteins. When high light-adapted cells were incubated with gabaculine, which inhibits Chl synthesis, and transferred to low light, the LHC II apoproteins were still synthesized and the 35S-labeled LHC II apoproteins remained stable after a 24 hour chase. These results suggest that Chl synthesis is not required for stability of the LHC II apoproteins in this alga. However, when the control cells are transferred from high light to low light, the amount of the four LHC II apoproteins per cell increases, whereas it does not in the presence of gabaculine. These results suggest that Chl synthesis is required for a photoadaptive increase in the cellular level of LHC II. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:16667702
Vallbracht, A.; Löhler, J.; Gossmann, J.; Glück, T.; Petersen, D.; Gerth, H. J.; Gencic, M.; Dörries, K.
A 27-year-old man with hemophilia type A and acquired immunodeficiency syndrome developed a subacute meningoencephalitis, associated with a normotensive internal hydrocephalus, 14 weeks before his death. From cerebrospinal fluid and brain autopsy material, a virus could be isolated and was classified by Southern blot analysis and restriction endonuclease reactions as the human polyomavirus BK. The postmortem findings of polyomavirus antigen and BK virus DNA in various cell types of the kidneys, lungs, and central nervous system strongly suggest that BK virus was the causative agent of a tubulointerstitial nephropathy, an interstitial desquamative pneumonitis, and a subacute meningoencephalitis with accentuation of the ventricular and meningeal surfaces of the brain. Besides distinctive cytopathic effects, the presence of intranuclear inclusions was a prominent histopathological feature. Therefore, the human polyomavirus BK should be regarded as a new candidate on the still growing list of opportunistic pathogens in acquired immunodeficiency syndrome. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8391217
Monck, J R; Robinson, I M; Escobar, A L; Vergara, J L; Fernandez, J M
Excitable cells are thought to respond to action potentials by forming short lived and highly localized Ca2+ gradients near sites of Ca2+ entry or near the site of Ca2+ release by intracellular stores. However, conventional imaging techniques lack the spatial and temporal resolution to capture these gradients. Here we demonstrate the use of pulsed-laser microscopy to measure Ca2+ gradients with submicron spatial resolution and millisecond time resolution in two preparations where the Ca2+ signal is thought to be fast and highly localized: adrenal chromaffin cells, where the entry of Ca2+ through voltage dependent Ca2+ channels triggers exocytotic fusion; and skeletal muscle fibers, where intracellular Ca2+ release from the sarcoplasmic reticulum initiates contraction. In chromaffin cells, Ca2+ gradients developed over 10-100 ms and were initially restricted to discrete submembrane domains, or hot spots, before developing into complete rings of elevated Ca2+ concentration. In frog skeletal muscle large, short-lived (approximately 6 ms) Ca2+ gradients were observed within individual sarcomeres following induction of action potentials. The pulsed laser imaging approach permits, for the first time, the capture and critical examination of rapid Ca2+ signaling events such as those underlying excitation-secretion and excitation-contraction coupling. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:7948669
Sverdrup, B; Klareskog, L; Kleinau, S
Many different agents, including mineral oil and silicone, have the capacity to act as immunological adjuvants, i.e., they can contribute to the activation of the immune system. Some adjuvants, including mineral oil, are known to induce arthritis in certain strains of rats after intradermal injection or percutaneous application. The aim of this study was to determine if common commercial cosmetic products containing mineral oil could induce arthritis in the highly susceptible DA (Dark Agouti) rat. Intradermal injection of five out of eight assayed cosmetic products without further additives resulted in arthritis with synovitis. One of the products induced a very aggressive arthritis, which had declined after 5-9 weeks. When this product was also assayed for arthritogenicity upon percutaneous administration, it induced a mild and transient arthritis in 5 out of 10 DA rats, whereas control animals showed no clinical signs of joint involvement. No arthritic reaction was seen in rats after peroral feeding with the most arthritogenic product or by intravaginal application of Freund's adjuvants. Silicone gel implants in DA rats did not cause arthritis. We conclude that mineral oils included in common commercially available products retain their adjuvant properties and are arthritogenic in the presently investigated arthritis-prone rat strain. There is yet no evidence that mineral oils present in cosmetics may contribute to arthritis in humans, but we suggest that this question should be subject to further investigation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9417771
Dukes, Thomas W.; Labonté, Bertrand
Quarantine, as a means of preventing disease importation, has been used for people and animals since the mid-19th century in Canada. The first animal quarantine facility in North America was established at Lévis, Québec in 1876. This quarantine station existed at Lévis until 1982 when it was closed and the function moved to Mirabel, Québec, near the International Airport. Veterinarians were in charge during the life of the Lévis Quarantine Station and some were also in charge of the Port of Quebec or a nearby District Office prior to the 1950's. In 1884 and 1886 the value of such a facility was illustrated in preventing the entry into Canada of contagious bovine pleuropneumonia and a vesicular disease. It was described in 1933 as “undoubtedly our most important quarantine station” and a year's operating costs as “trifling in comparison to losses which could occur if a foreign plague invaded this country”. This facility's history also illustrated the close veterinary and human medical cooperation during the early days of organized veterinary medicine in Canada. The station was an example for the establishment of other such facilities in North America. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:17423811
Parmley, R. T.; Barton, J. C.; Conrad, M. E.; Austin, R. L.
Lead is a universal environmental contaminant absorbed largely through the gastrointestinal tract by unknown mechanisms. Because lead absorption is influenced by iron content in the body and diet, we used ultrastructural radioautography and cytochemistry to study absorption of physiologic lead doses in the rat duodenal epithelial cell and compared these findings to those previously reported for iron absorption. Rat duodenal loops exposed in vivo to 210Pb for 1 minute demonstrated the majority of labels on the microvilli, terminal web, and apical cytoplasm. Specimens exposed to radiolead for 10 minutes demonstrated more abundant labeling with a relative increase in labeling of epithelial cell mitochondria, nuclei and basal cytoplasm, as well as phagocytic cells, endothelial cells, and circulating erythrocytes of the lamina propria. Timm's sulfide-silver method localized trace metals in epithelial cells. After administration of lead, a significant increase in staining was observed in microvilli, mitochondria, non-membrane-bound cytoplasm, and nuclear chromatin. The rapid appearance of absorbed lead in epithelial cell mitochondria and nuclei, as well as phagocytic cells in the lamina propria, was distinctly different from that reported for absorbed iron and suggests different mechanisms for the subcellular transport of these cations. The combination of radioautography and Timm's sulfide-silver staining provides the specificity and resolution needed for ultrastructural evaluation of lead absorption and should be useful in further studies of lead metabolism. Images Figure 10 Figure 11 Figure 12 Figure 4 Figure 5 Figure 6 Figure 7 Figure 3 Figure 8 Figure 9 Figures 1-2 PMID:464028
Rathjen, Anne H.; Robinson, Simon P.
Bruce's Sport is a mutant grapevine (Vitis vinifera L.) with green and white variegated fruit derived from the Sultana variety. The white regions of tissue have decreased polyphenol oxidase (PPO) activity resulting in a reduced capacity for browning. Active PPO from Sultana grapes was purified and had an apparent molecular weight of 40,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Western blots indicated that mature Sultana grapes contained a single 40-kilodalton PPO, and young Sultana berries also had small quantities of a 60-kilodalton protein. Bruce's Sport grapes had much less of the 40-kilodalton PPO and greater amounts of the 60-kilodalton band. Protease digestion of Bruce's Sport extracts decreased the proportion of the 60-kilodalton protein and increased the 40-kilodalton band. A cDNA clone of grape PPO was used to probe a northern blot of Sultana and Bruce's Sport RNA and hybridized to a 2.2-kilobase transcript in both grapevines. The level of PPO mRNA was high in the early stages of berry development but then declined. The results suggest that in grapevine the active 40-kilodalton form of PPO is synthesized as a precursor protein of at least 60 kilodaltons, and normal processing is interrupted in Bruce's Sport resulting in the accumulation of the 60-kilodalton inactive preform of PPO. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:16669082
Sirica, A. E.; Sattler, C. A.; Cihla, H. P.
The establishment of novel bile ductular cell cultures was accomplished with the use of explants of a hyperplastic bile ductular tissue preparation obtained from rat livers at 10 to 15 weeks after bile duct ligation or a bile ductular cell fraction isolated from this tissue preparation by a procedure involving Percoll density gradient centrifugation. Observations made on these primary explant and monolayer bile ductular cell cultures were limited to the first 3 days of culture where the morphologic features of the bile ductular epithelium remained fairly well preserved, while fibroblast contamination was found to be very low. These cultured cells also retained over this period a high specific activity for the bile ductular cell marker enzyme gamma-glutamyl transpeptidase, as well as possessed measurable but decreasing specific activities for leucine aminopeptidase and alkaline phosphatase. Karyotypic analysis of the cultured monolayer cells further showed them to be diploid. In addition, preliminary transplantation studies demonstrated the presence of well-differentiated bile ductular-like structures following inoculation of the freshly isolated bile ductular cell fraction into the interscapular fat pads of recipient rats. Images Figure 2 Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:2861743
Adebonojo, S. A.; Osinowo, O.; Adebo, O.
The experience with 45 patients with lung abscess over a three-year period at the University College Hospital (UCH), Ibadan, is presented. This study confirms the rarity of this disease among Nigerian children and its prevalence in young adults in the third and fourth decades of life. The most common presenting symptoms were purulent cough, chest pain, fever, and life-threatening hemoptysis which was the sole indication for emergency operation in 14 out of 16 patients who were treated surgically. The predominance of these abscesses in the right lung, especially in the superior segment of the lower lobe, supports the fact that aspiration of infected material, following depressed level of consciousness, esophageal obstruction, foreign bodies, and oral sepsis form the major causative factors in patients with lung abscess. The frequent association of sickle cell disease, bronchiectasis, hypertension, and pulmonary aspergilloma contribute significantly to the morbidity and mortality attendant to this disease in our environment. Twenty-nine patients were treated medically with five deaths and 16 patients were treated surgically with six deaths. The high operative mortality (37.5 percent) in this series was due to the extreme emergency conditions under which these patients were operated. ImagesFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:423274
Dalldorf, F. G.; Cromartie, W. J.; Anderle, S. K.; Clark, R. L.; Schwab, J. H.
The intraperitoneal injection of peptidoglycan-carbohydrate fragments from Group A streptococci produces a chronic, polyarticular, erosive synovitis in rats. The cell wall material accumulates rapidly in the liver, spleen, and lymph nodes, where it causes little injury. At the same time, selective localization and persistence of the material in the synovial and periarticular tissues occurs. Its presence in the joint is associated with acute and recurrent inflammation with focal synotivitis, pannus formation, joint destruction, and ankylosis. Cell wall fragments become localized in the synovial and periarticular tissues at a time when there are leukocytes in the bloodstream, which appear to contain the material. During this early phase vascular lesions appear in the synovium and in periarticular tissues with collections of fibrin, neutrophils, macrophages, and cell wall fragments near the venules and capillaries. Recurrent episodes of inflammation and joint injury, associated with persistent cell wall antigen within macrophages, were observed over a period of 90 days. Images Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 13 Figure 14 Figure 15 Figure 16 PMID:6996490
Gulizia, J. M.; Cunningham, M. W.; McManus, B. M.
Association of group A streptococci with acute rheumatic fever and valvular heart disease is well established; however the basis of valve injury remains unclear. In this study, anti-streptococcal monoclonal antibodies (MAbs) cross-reactive with myocardium were reacted with sections from 22 rheumatic valves, nine normal, five endocarditic, one 'floppy,' and one Marfan valve. In immunohistochemical studies, MAb reactivity was observed with cardiac myocytes, smooth muscle cells, cell surface and cytoplasm of endothelial cells lining valves, and valvular interstitial cells. Endothelial basement membrane and elastin fibrils reacted with the MAbs, whereas collagen was unreactive. Similar reactivity was seen with sera from acute rheumatic fever patients. The anti-streptococcal MAbs reacted with intravalvular myosin and vimentin in Western blots, and purified elastin competitively inhibited the binding of the anti-streptococcal MAbs to whole group A streptococci. The data show that human heart valves have numerous sites of immunoreactivity with anti-streptococcal MAbs and acute rheumatic fever sera of potential importance in the pathogenesis of rheumatic valvular injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:1704188
Bailey, T.; Biddlestone, L.; Shepherd, N.; Barr, H.; Warner, P.; Jankowski, J.
The maintenance of adult tissue architecture is largely dependent on the function of cadherins. E-cadherin is expressed in most epithelia, although it may be co-expressed with P-cadherin in basal layers of stratified epithelia. Adhesive function of cadherins relies on interactions with catenins. Many reports have characterized reduced expression of cadherins and catenins in tumors, including those of the gastrointestinal tract. This study aimed to characterize expression of E- and P-cadherins, and the catenins, in the progression of Barrett's esophagus to adenocarcinoma. Immunohistochemical analysis and Western blotting were performed on paraffin-embedded and fresh-frozen tissue using antisera to the selected cadherins and catenins. The results of this study have shown inappropriate expression of cadherins and catenins in neoplastic Barrett's mucosa. There was a significant reduction of E-cadherin expression as the Barrett's metaplasia-dysplasia-adenocarcinoma sequence progressed (P < 0.01). In contrast, P-cadherin, expressed in basal layers of squamous esophagus, was usually absent from Barrett's and dysplasia but was expressed in 17 of 24 carcinomas, especially at the advancing tumor edge. Reduced expression of catenins was also seen, but in some specimens, immunoreactivity was observed in neoplastic nuclei, suggesting mediation of a nuclear function such as transcriptional regulation. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9422531
Administration of amphiphilic drugs to experimental animals causes formation of myelinoid bodies in many cell types, accumulation of foamy macrophages in pulmonary alveoli and pulmonary alveolar proteinosis. These changes are the result of an interaction between the drugs and phospholipids which leads to an alteration in physicochemical properties of the phospholipids. Impairment of the digestion of altered pulmonary secretions in phagosomes of macrophages results in accumulation of foam cells in pulmonary alveoli. Impairment of the metabolism of altered phospholipids removed by autophagy induces an accumulation of myelinoid bodies. The administration of amphiphilic compounds thus causes pulmonary intra-alveolar histiocytosis which is a part of a drug-induced lysosomal storage or generalized lipidosis. The accumulation of drug-lipid complexes in myelinoid bodies and in pulmonary foam cells may lead to alteration of cellular functioning and to clinical disease. Currently over 50 amphiphilic drugs are known. Unique pharmacological properties necessitate clinical use of some of these drugs. The occurrence and severity of potential clinical side effects depend on the nature of each drug, dosage and duration of treatment, simultaneous administration of other drugs and foods, individual metabolic pattern of the patient and other factors. Further studies on factors preventing and potentiating adverse effects of amphiphilic drugs are indicated. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 8. FIGURE 9. FIGURE 10. PMID:6376111
Rekesh, D; Lyubchenko, Y; Shlyakhtenko, L S; Lindsay, S M
6-mercapto hexyl-oligonucleotides bind to a gold surface strongly enough to permit imaging by a scanning tunneling microscope (STM). STM images showed worm-like chains that were approximately 12-(A-wide for single-stranded DNA and 20-(A-wide for double-stranded DNA. The chain lengths corresponded to 3.4 +/- 0.4 A per basepair for double-stranded DNA and 2.2 +/- 0.4 A per base for single-stranded DNA. This unexpectedly short length for single-stranded DNA was confirmed using oligomers with both single- and double-stranded regions. When the attachment of the samples was weakened (by imaging in water or scraping with the STM tip) the images changed to pairs of "blobs," apparently reflecting the attachment points of the molecules to the gold surface. Given this interpretation, images of DNA containing a five-base bulge imply that the bulge bends the oligomer by 90 degrees +/- 20 degrees. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 PMID:8842244
Barbieri, F.; Cagnoli, M.; Ragni, N.; PedullÃ , F.; Foglia, G.; Alama, A.
Cyclin D1 is a cell cycle regulator of G1 progression that has been suggested to play a relevant role in the pathogenesis of several human cancer types. In the current study, the expression of cyclin D1 has been investigated in a series of 33 patients, with benign (10 patients), borderline (five patients) and malignant (18 patients) ovarian disease. Cyclin D1 protein and mRNA content were analysed by Western blotting and reverse transcriptase polymerase chain reaction respectively. The levels of cyclin D1 protein were undetectable in patients with benign disease, detectable in the majority of patients with borderline disease and elevated in those with ovarian carcinomas, being significantly related to the degree of malignancy (carcinoma vs benign, P = 0.0001; benign vs borderline, P = 0.0238). A significant relationship between cyclin D1 expression and tumour proliferative activity was also found (P = 0.000001). Moreover, eight benign lesions, two borderline tumours and 11 carcinomas proved to be suitable for the analysis of cyclin D1 transcript, and emerging data demonstrated significant agreement between protein abundance and mRNA expression. Results from the current study suggest that cyclin D1 expression is associated with the degree of transformation and most probably plays a role in the early development of ovarian malignancy. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:9155044
Wang, Co-Shine; Walling, Linda L.; Eckard, Kathleen J.; Lord, Elizabeth M.
Antiserum was raised in rabbits against a lily (Lilium longiflorum) anther-specific protein (LLA-15). Monospecific anti-LLA-15 antibodies were prepared to investigate the distribution of LLA-15 during anther development in a variety of flowering plants. Immunoblot analyses of total protein from floral and vegetative organs confirmed that LLA-15 or LLA-15-like proteins accumulated to detectable levels only in a discrete stage of anther development. In situ localization using anti-rabbit immunoglobulin G conjugated with gold particles confirmed that LLA-15 was specifically localized in the tapetal tissue of lily anthers. The maximal level of LLA-15 was strictly coincident with the peak of tapetal secretory functions. Immunoblots of two-dimensional polyacrylamide gels of lily anther proteins indicated that the seven LLA-15 isoforms ranged from isoelectric point 5.6 to 6.1. In vitro translation of lily anther mRNAs showed that four of these isoforms were primary products, the additional three being a result of posttranslational processing of the primary translation products. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8 PMID:16669007
Hatva, E.; Kaipainen, A.; Mentula, P.; Jääskeläinen, J.; Paetau, A.; Haltia, M.; Alitalo, K.
Key growth factor-receptor interactions involved in angiogenesis are possible targets for therapy of CNS tumors. Vascular endothelial growth factor (VEGF) is a highly specific endothelial cell mitogen that has been shown to stimulate angiogenesis, a requirement for solid tumor growth. The expression of VEGF, the closely related placental growth factor (PIGF), the newly cloned endothelial high affinity VEGF receptors KDR and FLT1, and the endothelial orphan receptors FLT4 and Tie were analyzed by in situ hybridization in normal human brain tissue and in the following CNS tumors: gliomas, grades II, III, IV; meningiomas, grades I and II; and melanoma metastases to the cerebrum. VEGF mRNA was up-regulated in the majority of low grade tumors studied and was highly expressed in cells of malignant gliomas. Significantly elevated levels of Tie, KDR, and FLT1 mRNAs, but not FLT4 mRNA, were observed in malignant tumor endothelia, as well as in endothelia of tissues directly adjacent to the tumor margin. In comparison, there was little or no receptor expression in normal brain vasculature. Our results are consistent with the hypothesis that these endothelial receptors are induced during tumor progression and may play a role in tumor angiogenesis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7856749
Grahn, B H; Cullen, C L
This retrospective clinical study describes the clinical manifestations, light microscopic findings, and diagnosis and treatment of acute and chronic lens rupture in the horse. Rupture of the lens capsule in the horse usually results in a chronic, blinding inflammation (phacoclastic uveitis) unless prompt surgical and medical therapies are implemented. The clinical manifestations of acute lens capsule rupture included: cataract; intralenticular displacement of iridal pigment; lens cortical fragments attached to the perforated lens capsule, iris, and corneal endothelium; miosis; aqueous flare; and usually a corneal or scleral perforation with ulceration or focal full thickness corneal edema and scarring. The clinical signs of chronic phacoclastic uveitis include blindness, phthisis bulbi, and generalized corneal opacification related to scarring, vascularization, pigmentation, and edema. In one horse, acute phacoclastic uveitis was successfully treated with phacoemulsification to remove the ruptured lens and medical therapy to control the accompanying inflammation. The affected eyes of the horses with chronic phacoclastic uveitis were enucleated because of persistent clinical signs of nonulcerative keratitis and uveitis, despite long-term medical management. The clinical manifestations and lack of improvement with medical therapy are similar in the horse, dog, cat, and rabbit. However, the histologic findings in equine phacoclastic uveitis differ significantly from those in the dog, and rabbit. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. PMID:10816830
Reichert, C. M.; O'Leary, T. J.; Levens, D. L.; Simrell, C. R.; Macher, A. M.
The acquired immune deficiency syndrome (AIDS) is a devastating new illness which appears to be sexually and parenterally transmissible. AIDS was first described in the male homosexual community; however, the disease has more recently been described among intravenous drug abusers, Haitians, hemophiliacs, and others. The etiologic agent is unknown. AIDS may represent an infection by a previously undescribed organism, a mutant of a known microorganism, or a multifactorial combination of environmental, immunologic, and genetic factors. As a consequence of the disease's seemingly irreversible ablation of the cell-mediated immune system, AIDS victims succumb to a variety of infections and/or unusual neoplasms. In its fully developed form, mortality approaches 100%. At autopsy the gross and microscopic pathology of the syndrome can be divided into three general categories: 1) morphologic manifestations of profound lymphoid depletion; 2) infections, usually with mixed opportunistic pathogens; and 3) unusual neoplasms, most frequently Kaposi's sarcoma or high-grade lymphomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 PMID:6311021
Goh, R. H.; Somers, S.; Jurriaans, E.; Yu, J.
OBJECTIVE: To review indications, contraindications, and risks of using magnetic resonance imaging (MRI) in order to help primary care physicians refer patients appropriately for MRI, screen for contraindications to using MRI, and educate patients about MRI. QUALITY OF EVIDENCE: Recommendations are based on classic textbooks, the policies of our MRI group, and a literature search using MEDLINE with the MeSH headings magnetic resonance imaging, brain, musculoskeletal, and spine. The search was limited to human, English-language, and review articles. Evidence in favour of using MRI for imaging the head, spine, and joints is well established. For cardiac, abdominal, and pelvic conditions, MRI has been shown useful for certain indications, usually to complement other modalities. MAIN MESSAGE: For demonstrating soft tissue conditions, MRI is better than computed tomography (CT), but CT shows bone and acute bleeding better. Therefore, patients with trauma or suspected intracranial bleeding should have CT. Tumours, congenital abnormalities, vascular structures, and the cervical or thoracic spine show better on MRI. Either modality can be used for lower back pain. Cardiac, abdominal, and pelvic abnormalities should be imaged with ultrasound or CT before MRI. Contraindications for MRI are mainly metallic implants or shrapnel, severe claustrophobia, or obesity. CONCLUSIONS: With the increasing availability of MRI scanners in Canada, better understanding of the indications, contraindications, and risks will be helpful for family physicians and their patients. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:10509224
Birrell, G B; Habliston, D L; Griffith, O H
Photoelectron imaging (photoelectron emission microscopy, PEM or PEEM) is a promising high resolution surface-sensitive technique for biophysical studies. At present, image quality is often limited by the underlying substrate. For photoelectron imaging, the substrate must be electrically conductive, low in electron emission, and relatively flat. A number of conductive substrate materials with relatively low electron emission were examined for surface roughness. Low angle, unidirectional shadowing of the specimens followed by photoelectron microscopy was found to be an effective way to test the quality of substrate surfaces. Optimal results were obtained by depositing approximately 0.1 nm of platinum-palladium (80:20) at an angle of 3 degrees. Among potential substrates for photoelectron imaging, silicon and evaporated chromium surfaces were found to be much smoother than evaporated magnesium fluoride, which initially appeared promising because of its very low electron emission. The best images were obtained with a chromium substrate coated with a thin layer of dextran derivatized with spermidine, which facilitated the spreading and adhesion of biomolecules to the surfaces. Making use of this substrate, improved photoelectron images are reported for tobacco mosaic virus particles and DNA-recA complexes. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:7858141
Narayan, K.; Cliff, W. J.
The purpose of this study was to establish a standardized experimental system to investigate the local effects of ionizing irradiation in the absence of systemic responses due to radiation. Twenty fully healed rabbit ear chambers in 13 rabbits were irradiated with single exposures of 7500 rads of beta-rays from a strontium-90 source. The irradiation resulted in an acute response, with cellular infiltration of the ear chambers, loss of vasomotion in arterioles, and vasodilatation. Over the weeks following irradiation, a gradual reduction in the number of blood and lymphatic vessels was noticed. A gradual reduction in the number of cells in the interstitium was also observed. Finally, only a few thin-walled blood vessels remained. Their endothelium contained no recognizable organelles and in places had disappeared completely, to expose the vascular basement membrane to the blood. These vessels were observed to be still flowing. No evidence either of capillary blockage due to swelling of endothelial cells or of platelet aggregation leading to thrombosis was obtained. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7055211
Jauregui, H. O.; Bradford, W. D.; Arstila, A. U.; Kinney, T. D.; Trump, B. F.
The morphologic characteristics of acute iron loading were studied in HeLa cells incubated in an iron-enriched Eagle's medium containing 500 mug/ml of iron. Chemical studies showed that ferritin synthesis was rapidly induced and the concentration of intracellular ferritin increased up to 72 hours. Closely coupled with an increase in HeLa cell ferritin was a marked decrease in the rate of cell multiplication. The significant ultrastructural findings of iron-induced HeLa cell injury are characterized by the appearance of both autophagic multivesicular and residual bodies over the first 72 hours of iron incubation. The prominence of multivesicular bodies was noted after only 4 hours' incubation, with iron and myelin figures first appearing after 6 hours. Thus, the partial arrest of cell multiplication was associated with an increase in cytoplasmic residual bodies containing iron and other debris. The distribution of intracellular ferritin within HeLa cells differs significantly from the distribution described previously in hepatic parenchymal cells. In HeLa cells, ferritin particles were confined to lysosomal vesicles and were not identified in cell sap, endoplasmic reticulum, or Golgi apparatus. Images Figure 8 Figure 1 Figure 9 Figure 10 Figure 11 Figure 12 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1155583
Myers, J. L.; Katzenstein, A. L.
The ultrastructural features of idiopathic bronchiolitis obliterans-organizing pneumonia (BOOP) were studied in 9 patients. As expected, the characteristic air space fibrosis was composed of spindled fibroblasts and myofibroblasts arranged concentrically within an electron-lucent stroma. In 6 patients there was evidence of incorporation of air space fibrosis into the interstitium. A surprising finding in all patients was the presence of extensive epithelial damage involving peribronchiolar alveolar septa. Necrosis and sloughing of alveolar lining cells resulted in denuding of epithelial basal laminae. Complex infoldings and deep invaginations of the denuded basal laminae into alveolar septa were common. These ultrastructural changes involving the interstitium are similar to those occurring in the interstitial pneumonias, and suggest that BOOP also results from acute epithelial injury. The different clinical manifestations and prognosis of these entities may relate to the peribronchiolar localization of the epithelial damage in BOOP compared with more diffuse involvement of distal lung in the interstitial pneumonias. Images Figure 2 Figure 3 Figure 1 Figure 4 Figure 5 Figure 6 Figure 7 PMID:3394793
Weis, L M; Rummel, A M; Masten, S J; Trosko, J E; Upham, B L
Many polycyclic aromatic hydrocarbons (PAHs) are known carcinogens, and a considerable amount of research has been devoted to predicting the tumor-initiating potential of PAHs based on chemical structure. However, there has been little research into the effects of PAHs on the epigenetic events of tumor promotion and no structural correlation has been made thereof. Gap junctional intercellular communication (GJIC) activity was used in this study as an epigenetic biomarker to determine the structure-activity relationships of twelve different PAHs. The PAHs used were naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, anthracene, 1-methylanthracene, 2-methylanthracene, 9-methylanthracene, 9, 10-dimethylanthracene, phenanthrene, fluorene, 1-methylfluorene, and fluoranthene. Results showed that PAHs containing bay or baylike regions inhibited GJIC more than did the linear PAHs. The nonnaphthalene PAHs were not cytotoxic as determined by a vital dye uptake assay, but the naphthalene compounds were cytotoxic at the higher doses, indicating that the down regulation of GJIC by these naphthalenes could be a consequence of general membrane damage. Inhibition of GJIC by all the inhibitory PAHs was reversed when the cells were refreshed with PAH-free growth medium. Inhibition of GJIC occurred within 0.5-5 min and correlated with the aqueous solubility of the PAHs. The present study revealed that there are structural determinants of epigenetic toxicity as determined by GJIC activity. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:9417772
Jagirdar, J; Lee, T C; Reibman, J; Gold, L I; Aston, C; Bégin, R; Rom, W N
Transforming growth factor beta (TGF-beta), a multifunctional cytokine and growth factor, plays a key role in scarring and fibrotic processes because of its ability to induce extracellular matrix proteins and modulate the growth and immune function of many cell types. These effects are important in inflammatory disorders with fibrosis and cancer. The asbestos-related diseases are characterized by fibrosis in the lower respiratory tract and pleura and increased occurrence of lung cancer and mesothelioma. We performed immunohistochemistry with isoform-specific antibodies to the three TGF-beta isoforms on 16 autopsy lungs from Quebec, Canada, asbestos miners and millers. There was increased immunolocalization of all three TGF-beta isoforms in the fibrotic lesions of asbestosis and pleural fibrosis. The hyperplastic type II pneumocytes contained all three isoforms. By contrast, there was differential spatial immunostaining for the TGF-beta isoforms in malignant mesothelioma, with TGF-beta 1 in the stroma but TGF-beta 2 in the tumor cells. These data are consistent with an important role for TGF-beta in accumulation of extracellular matrix and cell proliferation in asbestos-related diseases. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. PMID:9400723
Wyss-Coray, T.; Feng, L.; Masliah, E.; Ruppe, M. D.; Lee, H. S.; Toggas, S. M.; Rockenstein, E. M.; Mucke, L.
A number of important neurological diseases, including HIV-1 encephalitis, Alzheimer's disease, and brain trauma, are associated with increased cerebral expression of the multifunctional cytokine transforming growth factor-beta 1 (TGF-beta 1). To determine whether overexpression of TGF-beta 1 within the central nervous system (CNS) can contribute to the development of neuropathological alterations, a bioactive form of TGF-beta 1 was expressed in astrocytes of transgenic mice. Transgenic mice with high levels of cerebral TGF-beta 1 expression developed a severe communicating hydrocephalus, seizures, motor incoordination, and early runting. While unmanipulated heterozygous transgenic mice from a low expressor line showed no such alterations, increasing TGF-beta 1 expression in this line by injury-induced astroglial activation or generation of homozygous offspring did result in the abnormal phenotype. Notably, astroglial overexpression of TGF-beta 1 consistently induced a strong upmodulation of the extracellular matrix proteins laminin and fibronectin in the CNS, particularly in the vicinity of TGF-beta 1-expressing perivascular astrocytes, but was not associated with obvious CNS infiltration by hematogenous cells. While low levels of extracellular matrix protein expression may assist in CNS wound repair and regeneration, excessive extracellular matrix deposition could result in the development of hydrocephalus. As an effective inducer of extracellular matrix components, TGF-beta 1 may also contribute to the development of other neuropathological alterations, eg, the formation of amyloid plaques in Alzheimer's disease. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7604885
Kiefer, R.; Funa, K.; Schweitzer, T.; Jung, S.; Bourde, O.; Toyka, K. V.; Hartung, H. P.
Experimental autoimmune neuritis (EAN) is a monophasic inflammatory disorder of the peripheral nervous system that resolves spontaneously by molecular mechanisms as yet unknown. We have investigated whether the immunosuppressive cytokine transforming growth factor-beta 1 (TGF-beta 1) might be endogenously expressed in the peripheral nervous system of Lewis rats with actively induced and adoptive transfer EAN. TGF-beta 1 mRNA was upregulated to high levels in sensory and motor roots, spinal ganglia, and sciatic nerve as revealed by quantitative Northern blot analysis and in situ hybridization histochemistry, with peak levels just preceding the first signs of clinical recovery. TGF-beta 1 mRNA was localized to scattered round cells and dense cellular infiltrates, but only rarely to Schwann cell profiles. Double labeling studies revealed macrophages and subpopulations of T cells as the major cellular source of TGF-beta 1 mRNA. TGF-beta 1 protein was visualized immunocytochemically and localized to infiltrating mononuclear cells with peak expression around the same time as mRNA, in addition to some constitutive expression in axons and Schwann cells. Our studies suggest that the spontaneous recovery observed in Lewis rat EAN might be mediated by the endogenous elaboration of TGF-beta 1 within the peripheral nerve, and that macrophages might control their own cytotoxicity by expressing TGF-beta 1. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8546208
Johnson, Kenneth D.; Chrispeels, Maarten J.
Tonoplast intrinsic protein (TIP) is a member of a family of putative membrane channels found in bacteria, animals, and plants. Plants have seed-specific, vegetative/reproductive organ-specific, and water-stress-induced forms of TIP. Here, we report that the seed-specific TIP is a phosphoprotein whose phosphorylation can be monitored in vivo by allowing bean cotyledons to take up [32P]orthophosphate and in vitro by incubating purified tonoplasts with γ-labeled [32P]ATP. Characterization of the in vitro phosphorylation of TIP indicates that a membrane-bound protein kinase phosphorylates TIP in a Ca2+-dependent manner. The capacity of the isolated tonoplast membranes to phosphorylate TIP declined markedly during seed germination, and this decline occurred well before the development-mediated decrease in TIP occurs. Phosphoamino acid analysis of purified, radiolabeled TIP showed that serine is the major, if not only, phosphorylated residue, and cyanogen bromide cleavage yielded a single radioactive peptide peak on a reverse-phase high-performance liquid chromatogram. Estimation of the molecular mass of the cyanogen bromide phosphopeptide by laser desorption mass spectroscopy led to its identification as the hydrophilic N-terminal domain of TIP. The putative phosphate-accepting serine residue occurs in a consensus phosphorylation site for serine/threonine protein kinases. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:16653198
McMullen, John; Uhl, Timothy L.
Objective: To introduce an approach to shoulder rehabilitation that integrates the kinetic chain throughout the rehabilitation program while providing the theoretical rationale for this program. Background: The focus of a typical rehabilitation program is to identify and treat the involved structures. However, in activities of sport and daily life, the body does not operate in isolated segments but rather works as a dynamic unit. Recently, rehabilitation programs have emphasized closed kinetic chain exercises, core-stabilization exercises, and functional programs. These components are implemented as distinct entities and are used toward the end of the rehabilitation program. Description: Kinetic chain shoulder rehabilitation incorporates the kinetic link biomechanical model and proximal-to-distal motor-activation patterns with proprioceptive neuromuscular facilitation and closed kinetic chain exercise techniques. This approach focuses on movement patterns rather than isolated muscle exercises. Patterns sequentially use the leg, trunk, and scapular musculature to activate weakened shoulder musculature, gain active range of motion, and increase strength. The paradigm of kinetic chain shoulder rehabilitation suggests that functional movement patterns and closed kinetic chain exercises should be incorporated throughout the rehabilitation process. Clinical Advantages: The exercises in this approach are consistent with biomechanical models, apply biomechanical and motor control theory, and work toward sport specificity. The exercises are designed to stimulate weakened tissue by motion and force production in the adjacent kinetic link segments. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8. PMID:16558646
Ishikawa, O.; Ohigashi, H.; Imaoka, S.; Nakai, I.; Mitsuo, M.; Weide, L.; Pour, P. M.
Our previous studies have suggested that the presence of intact islets is essential for the induction of pancreatic exocrine tumors in the Syrian hamster model. To validate this, we investigated the effect of the carcinogen, N-nitrosobis(2-oxo-propyl)amine (BOP) in hamsters, in which homologous isolated intact islets were transplanted into the submandibular gland (SMG). Freshly isolated pure islets from hamster donors were transplanted into the left SMG of 20 female host hamsters. Ten of these hamsters (group 1) received BOP (40 mg/kg) weekly for 3 weeks. Another 10 hamsters (group 2) were kept untreated. In groups 3 and 4 (10 hamsters each) the salt solution or isolated pancreatic ductal cells, respectively, was injected into the gland. In other groups (10 hamsters each) islets were transplanted into the peri-SMG connective tissue (group 5) or into the renal subcapsular space (group 6). Hamsters of group 1 (40 mg/kg, weekly for 3 weeks) as were group 7 hamsters, which served as BOP-treated controls. All BOP-treated hamsters developed pancreatic lesions. Similar hyperplastic and atypical ductal/ductular proliferation and in situ carcinoma were found in the SMG of many group 1 hamsters. No such lesions were found in the SMG, peri-SMG, or renal subcapsular space of the other groups. Islets appear to be involved in carcinogenicity of BOP. The mechanism is obscure. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7485408
Fogel, M. A.; Boyd, C. D.; Leardkamolkarn, V.; Abrahamson, D. R.; Minto, A. W.; Salant, D. J.
The distribution and synthetic rate of glomerular basement membrane components was examined in the Passive Heymann Nephritis model of experimental membranous nephropathy. The extensive tissue injury that developed included subepithelial electron-dense deposits, podocyte foot process effacement, and expansion of the glomerular basement membrane. Levels of mRNA for type IV collagen, laminin, and fibronectin from isolated glomeruli was quantitated by slot-blot analysis and showed no change in experimental animals as compared to controls at either 1 week, 3 weeks, or 3 months after disease induction. Immunoelectron microscopy with gold-labeled anti-laminin IgG revealed no difference in the number of particles bound to the glomerular basement membrane of experimental animals and controls. Immunofluorescence with both type IV collagen antisera and anti-laminin antibody showed no difference in the intensity or pattern of staining. Despite extensive glomerular damage and glomerular basement membrane thickening, no evidence was found for either an increase in the synthetic rate of type IV collagen, laminin, or fibronectin or for an accumulation of basement membrane laminin within the damaged glomeruli. Alternate processes, such as diminished density of matrix components or accumulation of other unmeasured matrix constituents, presumably account for the expansion of the glomerular basement membrane seen in experimental membranous nephropathy. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1992771
Sillence, D. O.; Horton, W. A.; Rimoin, D. L.
Considerable progress has been made in the delineation of the genetic skeletal dysplasias, a heterogeneous group of disorders, that consist of over 80 distinct conditions. Morphologic studies have added a further dimension to the delineation of these conditions, their diagnosis, and the investigation of their pathogenetic mechanisms. In certain diseases, the morphologic alterations are characteristic and pathognomonic. In others only nonspecific alterations are observed, whereas in still other disorders growth-plate structure is essentially normal. Histologic, histochemical, and electronmicroscopic studies of growth-plate cartilage have provided new insights into the complexity of morphogenetic events in normal growth through the demonstration of morphologic defects in the genetic disorders of skeletal growth. As yet, very little is known of the biochemical abnormalities underlying the morphologic abnormalities. However, the great variety of morphologic findings points to a number of different pathogenetic defects in the synthesis, release, and assembly of connective tissue macromolecules and in the cells involved in growth-plate metabolism. Images Figure 4 Figure 8 Figure 5 Figure 7 Figure 10 Figure 6 Figure 9 Figure 1 Figure 3 Figure 2 PMID:474720
Achondrogenesis type I is a perinatally lethal, short-limb chondrodysplasia. Two types, IA and IB, have been distinguished by radiographic and histological criteria; both types appear to be inherited as autosomal recessive traits. The underlying molecular defects are not known, but histochemical studies have suggested that in achondrogenesis type IB, cartilage matrix is deficient in sulfated proteoglycans. We have studied cartilage extracts of one newborn with achondrogenesis type IB and found that proteoglycans were quantitatively reduced, and, unlike in control cartilage, they did not stain with toluidine blue and did not bind to DEAE. Impaired synthesis of sulfated proteoglycans was observed also in fibroblast cultures of the achondrogenesis IB patient. Radioactive labeling and immunoprecipitation studies indicated that core protein and side chains of proteoglycans were synthesized normally but were not sulfated. Analysis of sulfate metabolism in fibroblast cultures showed, in the patient's cells, normal intracellular levels of free sulfate but markedly reduced levels of the two intermediate compounds in the sulfate activation pathway, adenosine-phosphosulfate and phosphoadenosine-phosphosulfate. The results can be explained by deficient activity of one of the enzymes responsible for the biologic activation of sulfate, possibly similar to that observed in cartilage (but not in skin) of the recessive, nonlethal mouse mutant brachymorphic and leading to defective sulfation of macromolecules. Expression of the sulfation defect in cultured fibroblasts may offer a diagnostic tool for the disorder. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7977372
Brunicardi, F. Charles; Cotton, Ronald T.; Cole, George W.; Martinez, George
In order to face the challenges in healthcare this century, it is essential that surgeons understand modern leadership principles. One of the greatest leaders in history was Dr. Martin Luther King, Jr., who provides a shining example of level-5 leadership for us to study. The study of leadership principles of great leaders can provide us with practical methods of conflict resolution as well as inspiration to keep us engaged and focused. As leaders of the medical community, we face numerous challenges, including discovering and implementing new treatments for disease, providing care for the indigent, overcoming educational challenges such as incorporating the ACGME Core Competencies into our surgical training and promoting diversity in education. Achieving these goals is often hindered by the environment in which we labor-nearly 50 million are uninsured, the rising cost of medical care is currently at 16% of the GNP, and reimbursement rates are falling-which makes the practice of surgery a significant challenge. Effective leadership will be paramount in achieving these goals. In this editorial, which summarizes a presentation given to the Surgical Section of the annual National Medical Association meeting, five important leadership principles that are important for surgeons have been selected and related to the outstanding leadership of Dr. Martin Luther King, Jr. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:17304963
Collins, W. T.; Capen, C. C.; Döbereiner, J.; Tokarnia, C. H.
Fine structural alterations of thyroid C cells and parathyroid chief cells were evaluated after feeding dried leaves of the calcinogenic plant, Solanum malacoxylon, to cattle for 1, 6 and 32 days. Thyroid C cells initially were degranulated in response to the hypercalcemia, and parathyroid chief cells accumulated secretory granules. There was hypertrophy of thyroid C cells with well-developed secretory organelles but few secretory granules in the cytoplasm after 6 days of feeding S. malacoxylon. Inactive chief cells with dispersed profiles of endoplasmic reticulum and increased lysosomal bodies predominated in the parathyroid glands. Multiple foci of soft tissue mineralization were present in the heart, lung, and kidney. Thyroid C cells underwent hypertrophy and hyperplasia after 32 days of S. malacoxylon, and parathyroid chief cells were inactive or atrophic in response to the long-term hypercalcemia. Severe soft tissue mineralization was present throughout the cardiovascular system, lung, kidney, and spleen. These ultrastructural changes in thyroid C cells and parathyroid chief cells plus the widespread soft tissue mineralization observed after feeding cattle small amounts of S. malacoxylon are consistent with the recent evidence that leaves of this plant are a potent source of the active metabolite, 1,25-dihydroxycholecalciferol, of vitamin D. Images Figure 7 Figure 8 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:869016
Fredrickson, T. N.; Morse, H. C.; Yetter, R. A.; Rowe, W. P.; Hartley, J. W.; Pattengale, P. K.
Mouse strains congenic for ecotropic retrovirus genes have a much higher frequency of spontaneous lymphomas than the background NFS/N strain. In this study, most of these lymphomas have been identified as B-cell in origin by morphologic features, identification of immunoglobulin class, and cell-surface antigens. The classification suggested by Pattengale and Taylor proved to be applicable to the lymphomas studied. Most were of large follicular center cells and are considered typical of the type formerly designated as "reticulum cell sarcoma, type B." Many lymphomas contained a large proportion of nonneoplastic cells which partially obscured their neoplastic component. The role of ecotropic murine leukemia viruses as etiologic agents for B-cell lymphomas remains equivocal. However, because the only difference between the NFS/N and congenic mice is the expression of viruses in the latter, it appears that these viruses are somehow involved in induction of B-cell lymphomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 8 Figure 9 Figure 10 PMID:2998195
Toyokuni, S.; Okada, S.; Hamazaki, S.; Fujioka, M.; Li, J. L.; Midorikawa, O.
Rats intraperitoneally injected with a daily dose of cupric nitrilotriacetate (Cu-NTA), which contained 4 to 7 mg of copper/kg body weight, showed submassive liver necrosis, hemolytic anemia, and acute renal tubular necrosis at the beginning of the experiment and intermittently after 4 weeks of injections. All rats that survived over 8 weeks exhibited liver fibrosis with portal-portal, portal-central, and central-central bridging. In all rats that survived over 16 weeks, micronodular cirrhosis of the liver or extensive liver fibrosis was observed. The copper content of the cirrhotic/fibrotic liver was above 250 micrograms/g dry weight. Electron-microscopic x-ray analysis at day 93 revealed that copper stored in secondary lysosomes was always accompanied by a proportional amount of sulfur (correlation coefficient, 0.98; P less than 0.005). An experimental model of copper toxicosis in terms of copper-induced cirrhosis of the liver was established with exogenous copper chelated by nitrilotriacetate. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:2757117
Cordasco, Frank A.
Objective: To provide an overview of the evaluation and treatment of the patient with multidirectional shoulder instability. Data Sources: I searched MEDLINE for the years from 1980 to 2000 using the key words “shoulder joint,” “instability,” “dislocation,” “multidirectional shoulder instability,” and “inferior capsular shift.” Data Synthesis: Multidirectional instability is symptomatic glenohumeral subluxation or dislocation in more than 1 direction: anterior, inferior, or posterior. The primary pathology is a loose and patulous capsule, and the entity is more common than previously recognized. Multidirectional instability affects young, sedentary patients with generalized ligamentous laxity, often with bilateral symptoms and an atraumatic history, but it also affects athletes, many of whom have sustained injuries. Patients with multidirectional instability may also have Bankart lesions and humeral head impression defects. Conclusions/Recommendations: Patients with multidirectional instability must be identified before appropriate treatment can be initiated. If a course of rehabilitation fails to improve the patient's symptoms, an inferior capsular shift procedure has been demonstrated to be an effective surgical option. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10. PMID:16558641
Povlishock, J. T.; Rosenblum, W. I.; Sholley, M. M.; Wei, E. P.
Those microvascular endothelial events that parallel the evolution of platelet aggregation were evaluated in a well-controlled animal model. Cat pial microvessels were observed through a cranial window while local platelet aggregation was produced by intravenous injection of sodium fluorescein and simultaneous exposure of the pial vessels to light from a filtered mercury lamp that excited the fluorescein. The vessels were fixed in situ when the in vivo observations of a preselected vessel indicated early, intermediate, or advanced aggregation in that vessel. The preselected vessel was then harvested for ultrastructural study together with adjacent vessels from the illuminated field. These vessels and appropriate controls were compared in semiserial thin sections. The onset of platelet aggregation in both venules and arterioles was accompanied by focal endothelial lucency, vacuole formation, luminal membrane rupture, and swelling of the nuclear envelope. These changes were not found in control material. With intermediate aggregation these changes were more common, while with advanced aggregation these abnormalities occurred together with focal endothelial denudation. Thus, in this model denudation occurred only with advanced aggregation and was not a prerequisite for aggregation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:6824062
Lovett, D. H.; Johnson, R. J.; Marti, H. P.; Martin, J.; Davies, M.; Couser, W. G.
Secretion of glomerular cell-derived matrix metalloproteinases (MMPs) and their specific inhibitors, TIMP-1,2, may play an important role in the turnover of the glomerular extracellular matrix under basal and pathologic conditions. A 66-68 kd MMP secreted by cultured mesangial cells (MC) with activity against Type IV collagen and gelatin was purified and shown by amino-acid sequence analysis to be identical with a Type IV collagenase/gelatinase secreted by certain transformed tumor cell lines. The expression of the mesangial MMP in vivo was limited within the kidney to a small subset of the intrinsic glomerular mesangial cell population. After induction of acute anti-Thy 1.1 glomerulonephritis, there was a large increment in the number of Type IV collagenase-secreting MC, temporally coincident with the development of mesangial hypercellularity. The expression of the MMP inhibitor protein, TIMP-1, was not changed over this period. Ultrastructural studies localized the mesangial MMP to areas of evolving mesangiolysis and at sites of glomerular basement membrane disruption. Enhanced expression of the mesangial cell-derived Type IV collagenase may contribute to the evolution of glomerular injury in this model of immune complex-mediated glomerulonephritis or may be involved in the extensive matrix remodeling process that accompanies this form of glomerular injury. Images Figure 2 Figure 3 Figure 5 Figure 4 Figure 6 Figure 7 Figure 8 and Figure 9 Figure 10 Figure 11 Figure 12 PMID:1321565
Peña, P; Ugalde, C; Calleja, M; Garesse, R
We have cloned and determined the structure of the gene encoding the H(+)-ATP synthase beta subunit in two distantly related Drosophila species, D. melanogaster and D. virilis. The gene contains three exons that are extremely well conserved at the amino acid level, not only in the region encoding the mature protein but also in that encoding the leader peptide. Primer extension analysis indicates that the 5' untranslated region is extremely short, and reveals the presence of multiple initiation sites of transcription in both Drosophila species. The promoters of D. melanogaster and D. virilis H(+)-ATP synthase beta-subunit genes contain a conserved region surrounding the initiation transcription sites. Nucleotide sequence analysis has revealed the absence of canonical TATA and CCAAT boxes and the presence of several putative regulatory elements in both promoter regions, including GAGA, GATA and Ets binding sites. We have analysed the pattern of gene expression during D. melanogaster development. The mRNA is stored in oocytes, and activation of transcription takes place after 10 h of development. The expression of the nuclear-encoded H(+)-ATP synthase beta subunit is strictly coordinated with the expression of subunits 6 and 8 of the same complex that are encoded in the mitochondrial genome. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 8 PMID:8554535
Cayler, Glen G.
The death rate among neonates with cardiovascular disease is 50 percent during the first six months, with the majority dying during the first month. With early diagnosis most of these babies could be saved. In approaching the diagnosis of cardiac distress in the newborn, it is important to remember that the types of cardiovascular disease which cause symptoms and death early in life are quite different from those in older children. Lesions such as hypoplasia of the left heart, transposition of the great arteries, endocardial fibroelastosis, pulmonary atresia, mitral atresia, tricuspid atresia and truncus arteriosus are common, not rare, causes of cardiac distress in the newborn. A classification of neonatal cardiovascular diseases into seven pathophysiological groups is presented as a basis for an effective, practical approach to the differential diagnosis of the potentially lethal lesions. This approach is simplified further since over 90 percent of babies with cardiac distress have one of three lesions: (1) Large left-to-right shunt (characterized by the presence of massive plethora on the chest roentgenogram), (2) Large right-to-left shunt (association with intense cyanosis) or (3) Severe obstruction (including hypoplasia of the left heart, which is the most common cause of death due to cardiac distress during the first week of life). ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.Figure 8.Figure 9.Figure 10. PMID:4867629
Lowe, T; Chen, Q; Fernando, Q; Keith, R; Gandolfi, A J
We optimized proton-induced X-ray emission (PIXE) for tissue analysis in a toxicity-disposition study. We used cultured rabbit renal slices as the biological system to demonstrate the use of PIXE analysis. The renal slices were exposed to HgCl2, CdCl2, K2Cr2O7, or NaAsO2 alone or in a mixture. The PIXE analysis provides information on concentrations of elements above atomic number 11, and it is the only analytical technique that can determine 20-30 elements nondestructively in a single, small sample (approximately 5 mg) with detection limits of 1-5 ppm (dry weight). The renal slices are thin targets that yield X-ray emission spectra with low backgrounds and high elemental sensitivities. The nondestructive nature of PIXE and the ability to simultaneously measure uptake of multiple metals and endogenous elements are unique to this methodology. Images p302-a Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. A Figure 6. B Figure 6. C Figure 6. D Figure 7. A Figure 7. B Figure 7. C Figure 7. D p307-a PMID:8275986
Aarli, J A; Aparicio, S R; Lumsden, C E; Tönder, O
The binding of normal human serum, purified IgG and IgG fragments to central nervous tissue was studied by the anti-globulin consumption (AGCT) and immunofluorescence (IF) techniques. In the AGCT, F(ab')2 fragments failed to react, whereas IgG and Fc fragments did so. In IF experiments, the binding was localized to myelin sheaths, glia and neurons; Fab monomers at a protein concentration of 1-3 mg/ml dod not react with the tissue, but purified Fc fragments at 0-0625 mg/ml did. The binding is neither tissue- nor species-specific. Lipid and protein extraction procedures indicated that the factor responsible for binding to myelin was basic protein. It was concluded that the binding of normal IgG to central nervous tissue is medicated by the Fc part of the molecule. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:803915
Fuentealba, C; Guest, S; Haywood, S; Horney, B
The aims of this study were to characterize the histological changes observed in 34 accessioned cases of canine chronic hepatitis and to correlate these changes with the clinical pathological data. Cases of chronic hepatitis were subdivided into 6 categories: chronic active hepatitis (10/34), chronic persistent hepatitis (7/32), chronic cholestatic hepatitis (6/34), fibrosing hepatitis with cirrhosis (3/34), chronic cholangiohepatitis (3/34), and miscellaneous secondary hepatitis (5/34). Iron accumulation was a consistent finding in all livers examined. Although all cases of chronic hepatitis had elevated liver enzymes, no correlation was detected between biochemical parameters and the severity of morphologic changes. Similarly, no correlation was detected between rhodanine staining for copper and morphologic or biochemical indicators of cholestasis. However, presence of copper correlated well with reticulo-fibrosis (r = 0.8) and bile duct hyperplasia, suggesting that changes in the hemodynamics of the hepatic acini due to fibrosis could influence storage of copper. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. PMID:9187802
Rodgers, Vance D.; Kagnoff, Martin F.
In addition to abnormalities in systemic immune function, patients with the acquired immunodeficiency syndrome (AIDS) and the pre-AIDS syndromes have significant abnormalities in the distribution of T-cell subsets in the intestinal tract. Such immune deficits predispose such patients to opportunistic infections and tumors, many of which involve the gastrointestinal tract. For example, Candida albicans often causes stomatitis and esophagitis. Intestinal infections with parasites (Cryptosporidium, Isospora belli, Microsporidia) or bacteria (Mycobacterium avium-intracellulare) are associated with severe diarrhea and malabsorption, whereas viruses like cytomegalovirus and herpes simplex virus cause mucosal ulcerations. Clinically debilitating chronic diarrhea develops in many AIDS patients for which no clear cause can be identified. Enteric pathogens like Salmonella and Campylobacter can be associated with bacteremias. Kaposi's sarcoma and lymphoma involving the intestinal tract are now well-recognized complications of AIDS. Although AIDS is not associated with a pathognomonic liver lesion, opportunistic infections and Kaposi's sarcoma or lymphoma may involve the liver. ImagesFigure 3.Figure 4.Figure 5.Figure 6.Figure 7. PMID:3825111
Theodossi, A; Spiegelhalter, D J; Jass, J; Firth, J; Dixon, M; Leader, M; Levison, D A; Lindley, R; Filipe, I; Price, A
If skilled histopathologists disagree over the same biopsy specimen, at least one must have an incorrect interpretation. Thus, disagreement is associated with, although not the cause of, diagnostic error. The present study aimed to determine the magnitude of variation among 10 observers with a special interest in gastrointestinal histopathology. They independently interpreted the same biopsy specimens for morphological features which may discriminate between patients with Crohn's disease and ulcerative colitis and normal subjects. Thirty of 41 features had agreement measures significantly better than expected by chance (p < 0.05). The range of agreement in the 45 observer pairs over the final diagnosis was 65-76%. There was good agreement in discriminating between normal slides and those showing confirmed inflammatory bowel disease. For normal slides, however, the term nonspecific inflammation was often applied and without any consistency. In addition, true Crohn's disease slides were often and consistently thought to be ulcerative colitis. Having identified 11 important discriminatory morphological features, two multiple regression analyses were then carried out to produce a scoring system for inflammatory bowel disease. These results suggest there is considerable room for improvement in the reliability of colonic biopsy specimen interpretation and that this could probably be achieved using more exact definitions of morphological features and diseases. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8063225
Walker, D. H.; Harrison, A.; Murphy, K.; Flemister, M.; Murphy, F. A.
Ultrastructural, histopathologic, and virologic studies of adult hamsters infected with virulent Venezuelan equine encelphalomyelitis (VEE) virus (Subtype I-B) demonstrated precise chronologic and topographic progression of lesions and viral replication in extraneural sites. Thymus contained the earliest lesions and the highest initial and subsequent viral titers. No particular cytotropism was observed as highly efficient viral replication and severe cytonecrosis proceded. Early cortical necrosis of splenic periarteriolar lymphocytic sheath was followed by lymphoblastoid repopulation of the peripheral zone. Massive bone marrow necrosis was accompained by ultrastructural evidence of VEE viral particle production in reticulum cells, rubricytes, myeloid cells, lymphoblastoid cells, and megakaryocytes. Speed, efficiency, destructiveness, and relative sensitivity of virtually all lymphoreticular and hematopoetic cells were hallmarks of virulent VEE infection in the hamster. Images Figure 8 Figure 9 Figure 1 Figure 2 Figure 3 Figure 10 Figure 11 Figure 4 Figure 5 Figure 6 Figure 12A and B Figure 13 Figure 7 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 PMID:941983
McKeever, P. E.; Balentine, J. D.
Forty-eight rats received intracerebral injections of sterile colloidal carbon. At intervals between 10 minutes and 31 days after carbon injection, the rats were perfused with glutaraldehyde, and autopsies were performed. Between 10 minutes and 3 hours after injection, carbon particles were extracellular and located strictly within the needle track. During the first few days the carbon was ingested by macrophages. Initially absent, carbon-laden macrophages spread to the neuropil immediately surrounding the injection site at 7 to 31 days following injection. These carbon-laden macrophages frequently were elongated within the neuropil and resembled microglia. Carbon-laden macrophages eventually accumulated around local vessels and in perivascular spaces. Many macrophages containing carbon remained in the injection site at the longest sampling interval of 31 days. Results indicate two macrophage responses to colloidal carbon in the central nervous system: a) an indolent population remains in the injection site for at least 1 month and b) a second population of macrophages emigrates through the neuropil. They eventually surround local vessels and enter the perivascular space. The migrating macrophages offer an explanation for the peculiar perivascular cells in Krabbe's disease and may provide a link between the CNS parenchyma and immunocompetent cells. Images Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 1 Figure 2 PMID:696802
We stimulate the dynamical behavior of dissociated cytoplasm using the Reactive Flow Model (Dembo, M., and F. Harlow, 1986, Biophys. J., 50:109-121). We find that for the most part the predicted dynamical behavior of the cytoplasm is governed by three nondimensional numbers. Several other nondimensional parameters, the initial conditions, and boundary conditions are found to have lesser effects. Of the three major nondimensional parameters, one (D#) controls the percentage of ectoplasm, the second (C#) controls the sharpness of the endoplasm-ectoplasm boundary, and the third (R#) controls the topological complexity of the endoplasm-ectoplasm distribution. If R# is very small, then the cytoplasm contracts into a single uniform mass, and there is no bulk streaming. If R# is very large, then the cytoplasmic mass breaks up into a number of clumps scattered throughout the available volume. Between these clumps the solution undergoes turbulent or chaotic patterns of streaming. Intermediate values of R# can be found such that the mass of cytoplasm remains connected and yet undergoes coherent modes of motility similar to flares (Taylor, D.L., J.S. Condeelis, P.L. Moore, and R.D. Allen, 1973, J. Cell Biol., 59:378-394) and rosettes (Kuroda, K., 1979, Cell Motility: Molecules and Organization, 347-362). Images FIGURE 1 FIGURE 1B FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 PMID:3801576
Salunke, D M; Caspar, D L; Garcea, R L
Polyomavirus major capsid protein VP1, purified after expression of the recombinant gene in Escherichia coli, forms stable pentamers in low-ionic strength, neutral, or alkaline solutions. Electron microscopy showed that the pentamers, which correspond to viral capsomeres, can be self-assembled into a variety of polymorphic aggregates by lowering the pH, adding calcium, or raising the ionic strength. Some of the aggregates resembled the 500-A-diameter virus capsid, whereas other considerably larger or smaller capsids were also produced. The particular structures formed on transition to an environment favoring assembly depended on the pathway of the solvent changes as well as on the final conditions. Mass measurements from cryoelectron micrographs and image analysis of negatively stained specimens established that a distinctive 320-A-diameter particle consists of 24 close-packed pentamers arranged with octahedral symmetry. Comparison of this unexpected octahedral assembly with a 12-capsomere icosahedral aggregate and the 72-capsomere icosahedral virus capsid by computer graphics methods indicates that similar connections are made among trimers of pentamers in these shells of different size. The polymorphism in the assembly of VP1 pentamers can be related to the switching in bonding specificity required to build the virus capsid. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 PMID:2557933
Reyes, H; Sandoval, L; Wainstein, A; Ribalta, J; Donoso, S; Smok, G; Rosenberg, H; Meneses, M
Twelve episodes of acute fatty liver of pregnancy (AFLP) were diagnosed in 11 patients during the past 18 years in a general hospital in Santiago, Chile, with a prevalence of 1 per 15,900 deliveries. Acute fatty liver of pregnancy started between the 31st and 38th weeks of pregnancy, with malaise, vomiting, jaundice, and lethargy as the main clinical manifestations. Polydipsia (in nine episodes) and skin pruritus (in seven episodes) were unusual clinical findings. In two patients, pruritus started two and four weeks before AFLP, suggesting that an intrahepatic cholestasis of pregnancy preceded AFLP in those patients. Considering the current prevalence of both diseases in Chile, their association should be considered fortuitous. In another patient, two consecutive pregnancies were affected by AFLP, raising to three the number of reported patients with recurrent AFLP. In 11 episodes, liver biopsies supported the diagnosis of AFLP by showing small and midsized vacuolar cytoplasmic transformation as the most prominent histopathological feature. Positive intracellular fat staining was found in the four samples analysed. Studies by electron microscopy showed megamitochondria with paracrystalline inclusions in four samples. All the mothers survived, but fetal mortality was 58.3%. Several extrahepatic complications delayed maternal recovery for up to four weeks after delivery. This study confirms an improvement in maternal prognosis in AFLP, discusses the possibility of an epidemiological association with intrahepatic cholestasis of pregnancy, and increases the number of patients reported with recurrent AFLP. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8307428
Perez-Prat, Eva; Narasimhan, Meena L.; Binzel, Marla L.; Botella, Miguel A.; Chen, Zutang; Valpuesta, Victoriano; Bressan, Ray A.; Hasegawa, Paul M.
A cDNA clone was isolated that encodes the partial sequence of a putative endoplasmic reticulum Ca2+-ATPase of tobacco. The 1.497-kb insert had an open reading frame of 1.149 kb. The deduced peptide had the greatest homology to the endoplasmic reticulum Ca2+-ATPases of Drosophila and Artemia, followed by the mammalian and avian enzymes (SERCA2 and 3). The cDNA insert hybridized to a single mRNA of 4.4 kb from tobacco cultured cells or plant tissues. The level of this transcript was induced about 2-fold by NaCl shock in 428 mm NaCl-deadapted tobacco cells that were maintained in medium without salt, but not in unadapted cells. The level of this transcript was 3- to 4-fold higher in 428 mm NaCl-adapted cells growing in salt than in unadapted cells growing without salt. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:16653146
Bussolati, G.; Cassoni, P.; Ghisolfi, G.; Negro, F.; Sapino, A.
Recent evidence indicates that oxytocin (OT), in addition to the induction of myometrial and myoepithelial cell contraction, can influence proliferation and differentiation in developing mammary glands and in breast cancer cells, hence the interest in detecting and locating OT receptors (OTRs). We produced rabbit antisera and a monoclonal antibody against a synthetic peptide corresponding to the carboxy terminus of the predicted OTR sequence. We tested their specificity in immunoblasts and immunocytochemical tests. All of the antibodies specifically stained myometrium (at term of pregnancy). In the human breast, OTRs were detected in myoepithelial cells along ducts of normal lobules and in sclerosing adenosis. Intraductal cells in benign hyperplastic lesions were also positive. OTRs were demonstrated in cases of primary and metastatic carcinomas of the breast. In the same tissues, OTR gene expression was shown by reverse transcriptase polymerase chain reaction procedures detecting the specific mRNA. These results suggest that the interaction between OT and its receptors might play a role in the origin and evolution of non-neoplastic lesions and carcinomas of the breast. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:8669475
Schecter, A; Tiernan, T; Schaffner, F; Taylor, M; Gitlitz, G; VanNess, G F; Garrett, J H; Wagel, D J
A subset of workers was followed after exposure to polychlorinated biphenyls (PCBs), dioxins, and furans in an occupational medicine clinic setting. Patterns of PCBs found in adipose tissue resembled the pattern seen when soot from the incident or Aroclor 1254 was examined by GC-MS. Adipose tissue also revealed levels of hepta- and octachlorinated furans and dioxins as high as 8400 ppt in one repeatedly exposed worker. Control fat from patients with no known exposure to furans or dioxins was usually in the several hundred parts per trillion range for these isomers, but slightly over 2000 ppt in one sample. Electron microscopic analysis of liver biopsies from three patients who developed mild elevations of hepatic enzymes in their serum revealed morphologic alterations in some ways similar to those seen in animals after feeding experiments with PCBs, dioxins or the Binghamton State Office Building soot. These include pleomorphic mitochondria, giant mitochondria, prominent dense mitochondrial granules, cristae parallel to the long axis of the mitochondria and crystalline structure within same mitochondria as well as lipid droplets in liver cells and slightly dilated smooth endoplasmic reticulum. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. FIGURE 7. FIGURE 9. FIGURE 10. FIGURE 11. PMID:3928350
Infeld, D. A.; O'Shea, J. G.
Glaucoma is the third most prevalent cause of global blindness, accounting for over 5 million blind. It is common in Western Countries; the estimated prevalence of primary open angle glaucoma rises from a total prevalence of 1.1% to approximately 3% of our population as it ages. Ethnicity affects both the risk of developing glaucoma and the outcome. It is an expensive disease both to detect and to treat. Recent scientific advances include elucidation of the genetic mechanism behind the disease and the study of haemodynamic and biochemical co-factors in the development of glaucomatous optic neuropathy, particularly in relation to the pathogenesis of normal tension glaucoma. Several new types of topical medication have recently been developed for use in glaucoma; both the impact of these therapies and their cost effectiveness remain to be evaluated. There are widely differing regimes which effectively treat glaucoma; some ophthalmologists prefer early surgical intervention whilst others reserve surgery for relatively advanced disease. All methods of current treatment rely on the reduction of intra-ocular pressure; as yet there is no medication which has been definitively proven to be either neuroprotective or to influence favourably optic nerve perfusion. Despite this, most sufferers of glaucoma are able to lead lives of quality. Increased community awareness of glaucoma, and earlier detection of the condition, will doubtless result in decreased morbidity due to glaucoma. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:10320884
Hästbacka, J.; Superti-Furga, A.; Wilcox, W. R.; Rimoin, D. L.; Cohn, D. H.; Lander, E. S.
Atelosteogenesis type II (AO II) is a neonatally lethal chondrodysplasia whose clinical and histological characteristics resemble those of another chondrodysplasia, the much less severe diastrophic dysplasia (DTD). The similarity suggests a shared pathogenesis involving lesions in the same biochemical pathway and perhaps the same gene. DTD is caused by mutations in the recently identified diastrophic dysplasia sulfate-transporter gene (DTDST). Here, we report that AOII patients also have DTDST mutations, which lead to defective uptake of inorganic sulfate and insufficient sulfation of macromolecules by patient mesenchymal cells in vitro. Together with our recent observation that a third even more severe chondrodysplasia, achondrogenesis type IB, is also caused by mutations in DTDST, these results demonstrate a phenotypic series of three chondrodysplasias of increasing severity caused by lesions in a single sulfate-transporter gene. The severity of the phenotype appears to be correlated with the predicted effect of the mutations on the residual activity of the DTDST protein. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 3 Figure 6 PMID:8571951
Ballatori, N; Lieberman, M W; Wang, W
Methylmercury is a ubiquitous environmental pollutant and potent neurotoxin. Treatment of methylmercury poisoning relies almost exclusively on the use of chelating agents to accelerate excretion of the metal. The present study demonstrates that oral administration of N-acetylcysteine (NAC), a widely available and largely nontoxic amino acid derivative, produces a profound acceleration of urinary methylmercury excretion in mice. Mice that received NAC in the drinking water (10 mg/ml) starting at 48 hr after methylmercury administration excreted from 47 to 54% of the 203Hg in urine over the subsequent 48 hr, as compared to 4-10% excretion in control animals. When NAC-containing water was given from the time of methylmercury administration, it was even more effective at enhancing urinary methylmercury excretion and at lowering tissue mercury levels. In contrast, excretion of inorganic mercury was not affected by oral NAC administration. The ability of NAC to enhance methylmercury excretion when given orally, its relatively low toxicity, and is wide availability in the clinical setting indicate that it may be an ideal therapeutic agent for use in methylmercury poisoning. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9520359