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Microscopic Changes (microscopic + change)
Selected AbstractsDetection of EHV-1 and EHV-4 in placental sections of naturally occurring EHV-1- and EHV-4-related abortions in the UK: use of the placenta in diagnosisEQUINE VETERINARY JOURNAL, Issue 5 2003S. GERST Summary Reasons for performing study: EHV-1 and EHV-4 abortion diagnosis is based upon detailed examination of the aborted fetus. However, in some cases, only the placenta is available for examination. Furthermore, the contribution of lesions in the placenta to pathogenesis and diagnosis of EHV-1 and EHV-4 abortion has been neglected. Objectives: To assess the utility of placental examination in equine herpesvirus-1 (EHV-1) and EHV-4 abortion diagnosis. Methods: Sections of allantochorion from 49 herpesvirus abortions were analysed by PCR, in situ hybridisation and immunostaining. Results: Virus-specific nested PCR confirmed the presence of viral DNA in 46 cases; 41 cases were EHV-1-positive and 5 EHV-4-positive. Microscopic changes were nonspecific. Examination of the PCR-positive sections of allantochorion revealed EHV-1 DNA by in situ hybridisation (ISH) in 21 cases and EHV-4 in 4 cases. In 2 samples, DNA of both viruses was present on PCR and ISH. Viral antigen was found by immunohistology in 15 cases. Regarding the localisation of virus in the placentae, both viral DNA and antigen of EHV-1 and EHV-4 were found in endothelial cells of chorionic villi and, occasionally, in trophoblast epithelium. In the stromal endothelium, only EHV-1 was found. Conclusions: The data indicate that examination of placentae is a useful diagnostic aid in EHV-1 and EHV-4 abortion diagnosis. Potential relevance: Virological examination of the placenta should be come standard practice in equine abortion investigations, particularly in those cases where the fetus is not available for examination. [source] A Microscopic and Biomechanical Study of Skin and Soft Tissue After Repeated ExpansionDERMATOLOGIC SURGERY, Issue 1 2009RAN HUO MD BACKGROUND Conventional expansion inadequately restores damaged skin for patients with large areas of skin deficiency or who lack sources of normal skin. These patients require repeated skin expansions, but little is known about the outcomes of this procedure. OBJECTIVE To evaluate the microscopic changes and biomechanical properties of skin and soft tissue after repeated expansion. MATERIALS AND METHODS We prepared three groups of six pigs each: a conventional expansion group, a repeated expansion group, and a blank nonsurgical control group. We measured histology, ultrastructure, basic fibroblast growth factor (bFGF), stress,strain, stress relaxation, and stress strength. RESULTS Skin obtained after conventional expansion and repeated expansion was basically healthy, but the microscopic and biomechanical properties differed from those of nonexpanded skin, especially in the repeated expansion group. CONCLUSION Repeated skin expansion involves growth under stress, simultaneous injuries, and further repairs, with fibers showing more injury signs than cells. This article describes the microscopic changes and biomechanical properties that occur after repeated expansion. [source] Histologic and Ultrastructural Analysis of Ultraviolet B Laser and Light Source Treatment of Leukoderma in Striae DistensaeDERMATOLOGIC SURGERY, Issue 4 2005David J. Goldberg MD Background. Lasers and light sources emitting ultraviolet B (UVB) irradiation have been shown to repigment striae distensae. Objective. The purpose of this study was to analyze the histologic and ultrastuctural changes seen after UVB laser, or light source,induced repigmentation of striae distensae. Methods. Ten subjects with hypopigmented striae were selected. Five subjects were treated with an XeCl excimer UVB laser, and five subjects were treated with a UVB light device. Six months after the final treatment, the biopsies were evaluated for both standard and electron microscopic changes in melanocytes. Results. Analyses of biopsied skin after treatment with both the UVB laser and light source showed increased melanin content, hypertrophy of melanocytes, and an increase in the number of melanocytes in all patients. Conclusions. Repigmentation of striae distensae with either a UVB laser or light source is due to an increase in melanin pigment, hypertrophy of melanocytes, and an increase in melanocytes. DAVID J. GOLDBERG, MD, ELLEN S. MARMUR, MD, CHRYSALINE SCHMULTS, MD, MUSSARRAT HUSSAIN, MD, AND ROBERT PHELPS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Gross and Microscopic Findings in Patients Submitted to Nonablative Full-Face Resurfacing Using Intense Pulsed Light: A Preliminary StudyDERMATOLOGIC SURGERY, Issue 8 2002Enrique Hernández-Pérez MD background. Intense pulsed light (IPL) is a noncoherent, nonlaser, filtered flashlamp emitting a broadband visible light that has been shown to be effective in photoepilation, as well as in a number of vascular and pigmented lesions of the skin. Their efficacy has also been reported recently in the treatment of photodamaged facial skin. In the last condition, however, there are few studies showing the clinical and microscopic changes produced by IPL. objective. To assess the gross and microscopic changes that occur in photodamaged skin submitted to nonablative full-face resurfacing (NAFFR) using IPL. methods. Five women were submitted to five NAFFR sessions using IPL, one every 2 weeks. Skin biopsies and photographs were taken on all of the patients before the first procedure and after the last one, as well as weekly clinical assessment. Data concerning skin features (wrinkles, oiliness, thickness, dilated pores, and general appearance) were all assessed. Microscopic improvement of the aging features in the epidermis and dermis were all assessed. For the statistical analysis a t test for small samples was used. results. All the patients showed clinical and microscopic improvement in every one of the parameters assessed. The t test for small samples showed a statistically significant difference (P < 0.01) in epidermal thickness. conclusion. Facial photodamage was clinically and microscopically improved using IPL. Use of IPL as a rejuvenating method seems to be promising, with minimal side effects, a wide safety margin, and minimal downtime. [source] Folding of the tectal cortex by local remodeling of neural differentiationDEVELOPMENTAL DYNAMICS, Issue 3 2004Tatsuo Mima Abstract The folding pattern of the brain cortex is a precisely regulated process, but the mechanism involved during development remains unclear. A proposed theory predicts that the initiation of cortical folding depends, at least partly, on nonuniform distribution of neuronal differentiation and neurite growth. We tested this theory experimentally, by remodeling the normal pattern of neuronal cell differentiation within the embryonic optic tectum. Multiple foci of activated fibroblast growth factor signaling were created in the tectal cortex to locally change the neural differentiation and axonal growth patterns. At these foci, tectal cells remained undifferentiated and their radial and tangential migration was suppressed. These local changes in the neuronal cell differentiation resulted in a conversion of the tectal cortex from smoothly extended into precociously folded. The results provide in vivo experimental evidence that microscopic changes in the neuronal cell differentiation pattern can induce or remodel the folding pattern of the brain cortex. Developmental Dynamics 229:475,479, 2004. © 2004 Wiley-Liss, Inc. [source] Effects of 17 ,-estradiol exposure on Xenopus laevis gonadal histopathologyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2010Jeffrey C. Wolf Abstract The natural estrogen 17 ,-estradiol (E2) is a potential environmental contaminant commonly employed as a positive control substance in bioassays involving estrogenic effects. The aquatic anuran Xenopus laevis is a frequent subject of reproductive endocrine disruptor research; however, histopathological investigations have tended to be less than comprehensive. Consequently, a study was designed to characterize gross and microscopic changes in the gonads of X. laevis as a result of E2 exposure. Additional goals of this study, which consisted of three separate experiments, included the standardization of diagnostic terminology and criteria, the validation of statistical methodology, and the establishment of a half maximal effective concentration (EC50) for E2 as defined by an approximately 50% conversion of presumptive genotypic males to phenotypic females. In the first experiment, frogs were exposed to nominal concentrations of 0, 0.2, 1.5, or 6.0,µg/L E2. From these experimental results and those of a subsequent range finding trial, the EC50 for E2 was determined to be approximately 0.2,µg/L. This E2 concentration was utilized in the other two experiments, which were performed at different facilities to confirm the reproducibility of results. Experiments were conducted according to Good Laboratory Practice guidelines, and the histopathologic evaluations were peer reviewed by an independent pathologist. Among the three trials, the histopathological findings that were strongly associated with E2-exposure (p,<,0.001 to 0.0001) included an increase in the proportion of phenotypic females, mixed sex, dilated testis tubules, dividing gonocytes in the testis, and dilated ovarian cavities in phenotypic ovaries. A comparison of the gross and microscopic evaluations suggested that some morphologic changes in the gonads may potentially be missed if studies rely entirely on macroscopic assessment. Environ. Toxicol. Chem. 2010;29:1091,1105. © 2010 SETAC [source] Experimental haemophilic synovitis: rationale and development of a murine model of human factor VIII deficiencyHAEMOPHILIA, Issue 3 2004L. A. Valentino Summary., Haemophilia is a genetic disease as a result of the deficiency of blood coagulation factor VIII or IX. Bleeding is common, especially into joints where an inflammatory, proliferative synovitis develops resulting in a debilitating arthritis, haemophilic arthropathy. The pathogenesis of blood-induced haemophilic synovitis (HS) is poorly understood. The gross, microscopic and ultrastructural changes that occur in the synovial membrane following human and experimental hemarthrosis have been described. Repeated episodes of bleeding induce synoviocyte hypertrophy and hyperplasia, an intense neovascular response and inflammation of the synovial membrane. The component(s) in blood that initiates these changes is(are) not known, although iron is often proposed as one possibility. Here, we describe a novel murine model of human haemophilia A, which facilitates the examination of large number of animals and tissue specimens. The effects of hemarthrosis on the physical, gross and microscopic changes evoked following joint bleeding are described. Controlled, blunt trauma to the knee joint consistently resulted in joint swelling because of a combination of bleeding and inflammation. Hemosiderin was found in the synovial membrane. Similar to hemarthrosis in human haemophilia, joint bleeding resulted in acute morbidity evidenced by inactivity, weight loss and immobility. With time the animals recovered. The model of experimental murine HS described here has utility in the study of the pathogenesis of HS. This is the first of a series of articles, which will discuss the pathophysiology and characterize the model, with comparison of his model to others which have been published previously. It should provide a useful model to test potential therapeutic interventions. [source] A study of gross, histological and blood biochemical changes in rainbow trout, Oncorhynchus mykiss (Walbaum), with rainbow trout gastroenteritis (RTGE)JOURNAL OF FISH DISEASES, Issue 4 2010J Del-Pozo Abstract The mechanisms behind the pathogenesis of rainbow trout gastroenteritis (RTGE) are still unknown. This study examined the macroscopic and microscopic changes in trout with RTGE (RTGE+), as well as the blood chemistry. A total of 464 rainbow trout were sampled from 11 sites in the UK, comprising 152 RTGE+ fish and 330 random, apparently healthy fish. A case definition for RTGE was assessed by the analysis of its agreement with three laboratory tests: histopathology, packed cell volume and kidney bacteriology. Cluster analysis indicated the presence of three distinct presentations within the population of RTGE+ fish. Cluster A included gross signs associated with moribund RTGE+ fish, and clusters B and C identified gross signs consistent with concurrent diseases, notably furunculosis, enteric redmouth and proliferative kidney disease. The information gained was used to select RTGE+ fish without concurrent disease for the analysis of RTGE pathogenesis with blood biochemistry. This analysis revealed a severe osmotic imbalance and a reduced albumin/globulin ratio as indicatives of selective loss of albumin. These findings are compatible with a protein losing enteropathy. [source] Liver pathology in compound heterozygous patients for hemochromatosis mutationsLIVER INTERNATIONAL, Issue 4 2002Maximilian Schöniger-Hekele Abstract: Background: While hepatic pathology of homozygous carriers of the C282Y mutation of the HFE haemochromatosis gene is well defined, the impact of the C282Y/H63D compound heterozygous carrier state is unknown. Aims: To evaluate the range of hepatic pathology in C282Y/H63D compound heterozygous patients. Patients: 25 C282Y/H63D compound heterozygous patients with and without known underlying liver disease underwent liver biopsies for evaluation or abnormal liver tests. Eleven cadaveric liver donors with HFE wild type served as controls. Methods: Mutations in the HFE gene were detected by polyacrylamide gel electrophoresis (PAGE) separation of digested polymerase chain reaction (PCR)-amplificates. The extent of light microscopic changes of liver architecture were studied on haematoxylin, eosin (H. E.) stains. In addition, the extent and the distribution of iron deposition was graded on Prussian blue-stained sections and hepatic iron was quantified by atom absorption spectroscopy. Serum ferritin concentration and the transferrin saturation index were measured using routine laboratory methods. Results: Patients without underlying liver disease (n = 15): Hepatic inflammation was seen in only 8% but fibrosis was found in 36% of compound heterozygous patients. Eighty six percent of those patients had stainable iron predominantly found in Rappaport's zone 1 and 2, but all had a liver iron-index < 1.9. Transferrin saturation was found elevated in 36% of compound heterozygous patients. Patients with liver fibrosis showed significantly higher ferritin levels than patients without liver fibrosis (1110 ng/mL versus 307 ng/mL, p < 0.05). Patients with underlying disease (n = 10): In compound heterozygous patients, 77% had hepatic inflammation and 88% fibrosis. Stainable iron (44%) was less frequently found than in patients without underlying liver disease. Hepatic iron-index in patients with underlying liver disease was always below 1.17; transferrin saturation was elevated in only 22% of the compound heterozygous patients. Histologic hepatic iron-index was significantly lower in patients with underlying disease (median 0.047) as compared to patients without underlying liver disease (median 0.274, P < 0.05). Conclusions: The underlying liver disease determines the extent of hepatic pathology seen in livers of compound heterozygous patients. However, considerable histologic fibrosis can also be found in compound heterozygous patients without underlying liver disease. [source] Neuropathological changes in vibration injury: An experimental studyMICROSURGERY, Issue 1 2005Hani S. Matloub M.D. Vibration syndrome, a clinical condition arising from chronic use of vibrating tools, is associated with a spectrum of neurovascular symptoms. To date, only its vascular pathology has been extensively studied; we sought to determine what direct neurologic injury, if any, is caused by vibration. Hindlimbs of anesthetized rats were affixed to a vibrating platform 4 h a day for 7 days. Study animals were vibrated with set parameters for frequency, acceleration, velocity, and amplitude; control animals were not vibrated. On day 7, nerves were studied by light and electron microscopy. While light microscopy showed minimal histologic differences between vibrated (n = 12) and control (n = 12) nerves, electron microscopic changes were dramatic. Splitting of the myelin sheath and axonal damage (e.g., myelin balls and "finger ring") were consistently seen in both myelinated and nonmyelinated axons. Despite relatively short vibration, definite pathology was demonstrated, suggesting that vibration syndrome has a direct neurologic component. © 2005 Wiley-Liss, Inc. Microsurgery 25:71,75, 2005. [source] | |||||||||||||