Cisplatin (cw-diamminedichloroplatinum II; CDDP) is a broad spectrum anti-cancer agent with severe toxic side effects. New platinum based chemotherapeutic agents with similar properties are in constant development. Poly-plat (Poly-[(teans-l,2-diaminocyclohexane) platinum]-carboxyamylose), a novel second generation platinum chemotherapeutic agent, has been shown to be less toxic compared to CDDP. The purpose of this paper was to examine the morphological changes in the Kupffer cells in the liver after poly-plat treatment in rats and compare the results obtained after CDDP. Peripheral blood was also examined for levels of circulating leukocytes.

Wistar rats (120-160 g) were given intraperitoneal injections of either CDDP (9 mg/kg in 0.9% sodium chloride) or poly-plat (10 mg/kg in 0.9% sodium chloride) over a five day period. Controls were treated with equal amounts of the vehicle of injection. Peripheral blood was collected via tail vein beginning 1 day prior to treatment and continuing 10 days after treatment.

Rotaviruses are complex, relatively large (1000 Å) nonenveloped icosahedral viruses. They are the major causative agents of severe diarrhea in children and animals. Annually an estimated 1 million children die from rotavirus-induced gastroenteritis worldwide. Medical relevance, intriguing structural complexity, and several unique strategies in the morphogenesis and replication have provoked extensive molecular biological and structural studies on rotaviruses in recent years.

Rotaviruses are double-stranded RNA (dsRNA) viruses belonging to the family Reoviridae. Each of the 11 segments codes for one protein. Of the eleven proteins encoded by the genomic RNA, six are structural and five are non-structural. Structural studies have shown that mature rotaviruses are triple-layered particles (TLPs). During the process of cell entry the outer-most layer consisting of VP7 and the spike protein VP4 is lost and the resulting double layered particles (DLPs) become transcriptionally active (Fig. 1 A). During the process of transcription, the DLPs maintain their structural Integrity.

Endemic and epidemic viral gastroenteritis are major causes of morbidity worldwide and are frequently a major cause of death in the developing world. Rotavirus, adenovirus, calicivirus, astrovirus, and the Norwalk virus family are the viruses most often associated with gastroenteritis. Of these, the major cause of epidemic viral gastroenteritis in the US is Norwalk-like viruses. Gastroenteritis caused by this virus group is responsible for such outbreaks in settings such as cruise ships, schools, camps, hospitals, day-care and extended care facilities, football games and festivals.

As early as the 1950s and 1960s electron microscopy (EM), including negative stain EM, was established as a diagnostic tool for identifying viruses. Negative stain EM is especially useful for identifying viruses that are difficult or impossible to culture (eg. viruses in the Norwalk family). The first Norwalk virus was identified in the 1969 by immune-negative stain EM. Many antigenic types were identified soon afterward that did not cross-react with the prototype Norwalk virus.

Analysis of Hepatitis C virus (HCV) assembly and packaging, and the study of virus-cell interactions, have been impeded by the lack of a robust cell culture system and a viable small animal model. Recently, an alternative approach utilizing recombinant gene technology has been implemented. We describe a system in which specific HCV genes are cloned into a baculovirus to form a recombinant baculovirus expression vector that produces HCV proteins that self-assemble into enveloped virus-like particles (VLP). Four HCV structural genes were cloned into the baculovirus expression vector under the control of the polyhedrin promoter, and were then recombined with baculovirus DNA. A baculovirus with no HCV insert served as a negative control (wild-type). Ovary cells (Spodoptera frugiperda) were infected with either the recombinant or wild type baculovirus. Five-days post-infection, a group of cells were harvested, fixed in McDowell-Trumps solution, and routinely prepared for transmission electron microscopy (TEM).

The application of both classical and advanced microscopy to the exploration of abnormal, human, fetal development (birth defects) and to other forms of human, fetal disease has generated a wealth of information, often documented by dramatic images. We have studied, at varying levels of inquiry (simple inspection to molecular analysis), some 10,000 normal and abnormal specimens. For presentation purposes, we first demonstrate the use of imaging in explorations of the fetal habitat (the gestational sac). Our studies reveal a variety of fetal surface encounter lesions (skin-to-amnion). Many of these lesions in the past have been erroneously interpreted. These include fetal amputations, strangulations, and also the reimplantation of amputated parts to ectopic sites. We have also explored, by various imaging techniques, developmental abnormalities within a variety of fetal organs.

The comparative morphology of the tongue microvasculature has been studied in different animals, such as in man (Okada et al, 1993, Matsukawa and Okada, 1994), rats (Nagato et al., 1989, Ohshima, et al, 1990, Selliseth and Slvig, 1993), dogs (Kishi et al, 1986, Kishi et al 1988), goats(Scala et al, 1992), monkeys (Patterson, et al, 1992, Okada et al, 1993, Matsukawa and Okada, 1994), marmosets (Okada et al, 1993, Matsukawa and Okada, 1994) and shrews (Okada et al, 1993, Matsukawa and Okada, 1994), but apparently none in rabbits. The disposition of the blood vessels of the rabbit's lingual papillae were studied by injecting them with Mercox resin and posterior corrosion, thus obtained microcorrosion casts were observed in the scanning electron microscope.

Male and adult rabbits were used to obtain our models. After perfusion with heparin 0,1M, pH 7.4 and glutaraldehyde, both in the same buffer, the vessels were filled as reported above.

Hepatomegaly, characterized by increased liver weight due to hyperplasia or hypertrophy, can be induced in many species by various drugs or environmental toxins. In rats, hepatomegaly is more usually associated with increases of smooth endoplasmic reticulum in hepatocytes and the associated induction of cytochrome P450 enzymes or with hepatocellular peroxisomal proliferation. In this study, a substituted pyrimidine derivative given to rats resulted in hepatomegaly with an unusual selective increase in hepatocellular rough endoplasmic reticulum (RER).

Female Sprague-Dawley rats were given repeated oral doses of a substituted pyrimidine derivative for 28 consecutive days. Livers were collected at necropsy, weighed, fixed in 10% neutral buffered formalin and processed to paraffin sections stained with hematoxylin and eosin (H&E) for light microscopic evaluation. Portions of formalin-fixed liver were transferred to buffered 2.5% glutaraldehyde for ultrastructural evaluation. Specimens were processed into epoxy resin and thin sections were examined with a JEOL 1200EX transmission electron microscope.

Some pathologic alterations in animal tissue sections, because of low resolution, are not identified using light microscopy. Availability of higher resolution in electron microscopy (EM) confers a decisive role on EM for diagnostic pathology that is well accepted. Much has already been contributed by EM in understanding of liver diseases. However, EM has been further refined by adding a quantitative facet to the results. Morphometric technique allows transfer of facts acquired from 2-dimensional samples, e.g., electron micrographs, to a 3-dimensional perspective. In addition, the technique is valuable in determining the significance of the alterations especially in instances where the changes numerically are either scanty or indistinguishable from a normal appearance of the cells or tissues (Fig. 1).

In our work on the effects of several different PCB congeners, one of the compounds, namely, congener number 153 was studied to obtain morphometric data on the lesions in the liver of rats given the congener in the diets for 13 weeks.

Pathological changes of hepatocytes from rats fed a 30% ethanol-derived calories diet for three weeks include noticeable ultrastructural changes including steatosis and hypertrophy of the smooth endoplasmic reticulum. We sought to examine hepatocytes of deer mice administered ethanol in an inhalation chamber for two weeks to determine if subtle changes occur in hepatocyte organelles prior to steatosis.

Two strains of Peromyscus maniculatus, ADH-positive possessing hepatic cytosolic alcohol dehydrogenase and ADH-negative deer mice lacking this enzyme were purchased from the Peromyscus Genetic Stock Center (Univ. of South Carolina). They tested negatively for Hanta viruses. A morphometric analysis of the ultrastructure of ADH+(n=14) and ADH- (n=14) controls as well as experimentals exposed to chronic, intoxicating levels of ethanol was conducted. Blood ethanol levels were maintained between 1.25-1.75 mg/ml for two weeks in the experimentals.

Cancer is a disease characterized by uncontrolled cell divisions in which the molecular controls for cytoskeletal regulation are bypassed. Cell division is governed by centrosomes, microtubule-organizing cell organelles which are crucial for the organization of the mitotic apparatus during mitosis and cell division. Because centrosome abnormalities are observed in the most common human cancers, we used immunofluorescence and transmission electron microscopy to determine centrosome organization in the human androgenresponsive prostate cancer cell line LNCaP and the androgen-independent prostate cancer cell line DU145. During interphase, centrosomes are located in close vicinity to the outer nuclear membrane, duplicate during S-phase, and become separated to the mitotic poles during the transition from interphase to mitosis. Centrosome regulation is based on a number of different factors which are only partly understood. Hormones play a role during developmental regulation of prostates which might trigger the activation of centrosome proteins and consequent cell divisions in order to ensure tissue growth.

Cell adhesion and cell adhesion molecules (CAMs) play a crucial role in testicular development and function. The seminiferous epithelium, the functional unit of the testis, represents a three dimensional architecture of supporting Sertoli cells (SC), and developing germ cells (GC). The seminiferous epithelium, therefore, must be receptive not only to individual cell growth and differentiation, but also to cell-cell interactions. Morphologically distinct cell-cell interactions occur between SC and GC and also between SC.[1] In general, these junctions can be categorized into three types: adhesive, occluding, and gap junctions. The orientation and function of these junctions are interaction dependent. For example, desmosome-like junctions (spot desmosomes) are found between SC and GC. These junctions are present in the basal and intermediate compartments of the testis and serve to translocate developing GC. SC-SC interactions, like the zonula occludens (tight junction), function as vectorial mediators, maintaining the blood-testis barrier and SC polarity.

The vascular endothelium is the interface with hyperglycemia in uncontrolled diabetes mellitus and its complications, including nephropathy, myocardial infarction, blindness, and gangrene. To mimic the vascular endothelium in a controlled experimental situation, we use the endothelial cell line (CRL 1998) obtained from The American Type Culture Collection. Cells are grown to confluency in Media 199 containing 10% fetal calf serum and gentamicin (50mg/ml). The growth media is replaced with experimental media containing high glucose (30mM), insulin (20 Units/ml), or heparin (500 Units/ml) either separately or in combinations. Cells are briefly trypsinized, pelleted, embedded, and sectioned with a Diatome diamond knife for TEM or for SEM, grown on 0.45um filters, followed by fixation and air-drying in situ: this approach to culture allows cells to obtain a polar, more natural phenotype than monolayers on glass or plastic.

Incubation in high glucose results in loss of confluency, production of intercellular gaps, and fewer mitotic figures.

Monocrotaline (M) induces pulmonary hypertension (PH) characterized by increased pulmonary arterial pressure, thickened pulmonary arterial walls, and right ventricular hypertrophy (RVH). In addition, numerous mast cells (MC) have been localized in M treated rats and these cells may have a role in causing PH and other lung injury because of their content of serotonin, which is a vasoconstrictor. Nitric oxide (NO) is a vasodilator that has been used in treatments of human patients and experimental animals with PH. The purpose of this study is to determine if NO inhalation can prevent or reverse RVH or MC accumulation induced by M.

Adult male Sprague-Dawley rats were divided into 5 groups (C, M3, MN3, M5, MN5). Group C served as controls without treatments. Groups M3 and M5 received one single subcutaneous injection of M (80mg/kg BW) and were sacrificed at 3 weeks (M3) or 5 weeks (M5) after injection.

Nitric oxide synthase (NOS) catalyzes the conversion of L-arginine to citrulline and the highly reactive free radical species, NO. Two major constitutive isoforms, neuronal and endothelial NOS, have been ented in the retina. These constitutive isoforms produce small amounts of NO while the inducible isoform, iNOS, produces high levels of NO. Excess production of NO by iNOS has beem implicated in the complications of diabetes. Since NO is a highly labile molecule, its potential localization is best achieved by immunocytochemical studies of NOS.

Semiquantitative colloidal gold labeled immunocytochemical studies of endothelial NOS (eNOS) and iNOS were done on sections of neural retina in eyes of obese, noninsulin dependent diabetic BBZ/Wor rats with diabetes of five months to twelve months duration. Age matched, nondiabetic control retinas were from eyes from BBDR/Wor rats.

Levels of iNOS were elevated in diabetic (33.9 ± 10.0 gold particles) as compared to age matched nondiabetic control (3.5 ± 2.8 gold particles) retinas.

Cephalad pulmonary mucociliary clearance driven by cilia of the ciliated airway epithelium provides probably the most important line of defense against inhaled toxins and particulate material for organs of the thoracic cavity. We demonstrate the reorganization of the cytoskeleton and the endoplasmic reticulum of airway epithelial cells upon cigarette smoke inhalation by employing DIC, LSCM, TEM and widefield fluorescence microscopy and have correlated this reorganization to changes in ciliary beat frequency (CBF) via FFT analysis. Neonatal pigs were used to provided healthy tracheal epithelial tissue. Exposure to cigarette smoke causes rapid ultrastructural changes including: ciliary distortion and detachment, ciliary abscission and severe alteration in endoplasmic reticulum structure suggesting profound disruption of essential membrane-cytoskeletal linkages.

To examine changes in CBF we describe a simple approach, using a laser scanning confocal microscope (LSCM) and an analog-to-digital computer converter/analyzer for the acquisition of data from biological systems that undergo rapid periodic movement, such as ciliary motion.

There have rarely been reported on radiation induced hematopoietic cells apoptosis and the recovery ,the expression and significance of oncogenes, tumor suppresser genes, hematopoietic grouth factors and their receptors in bone marrow.

By meams of routine pathology, specific stainning, electron microscope, immunocytochemistry, image analysis, in situ hybridization, in situ terminal end labelling, in situ PCR and DNA electrophoresis, The machanisms of hematopoietic cells apoptosis and then recovery in mouse bone marrow were studies through LAC A mouse total body irradiation with 60Co γ -rays.

The results showed: The bone marrow in each radiated group appeared obvious injury and then recovery, and the lessions were the most typical in 5.5Gy irradiation group, the pathologic changes were divided into four phases: namely the phase of hematopoietic cells apoptosis,bone marrow at 6hours after radiation. Furthermore, the higher radiation dose, the more the apoptotic cells were(table l).

Ultrastructural Pathology of capillary endothelial cells in autoimmune inflammatory myopathies has been intensively investigated in the last two decades, but much less is known about the alterations of capillary pericytes. In other diseases as diabetes and arterial hypertension perycites abnormalities have been reported. In this work we report the pericyte ultrastructural pathology in autoimmune inflammatory myopathies.

Patients admitted to the study were attending the rheumatology clinics at the Caracas University Hospital. Diagnoses were systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, and muscle paraneoplastic phenomenon.

Needle muscle biopsies were processed with routine techniques for transmission electron microscopy and observed in a Hitachi H-500 electron microscope.

Two different processes were observed, pericyte hypertrophy and cell degeneration. In the first one cytoplasmic proliferation is evident (Fig. 1). Some capillaries embraced by the pericyte were found (Fig. 2). In the second one cytoplasmic vacuolation and capillary necrosis (Fig. 3) were evident. Usually, pericyte and endothelial degeneration were concomitant.

Modern diagnosis of biopsied muscle requires a multidisciplinary approach, including routine histology and immunohistochemistry, cryosectioning for histochemistry, and (in selected cases) electron microscopy or biochemical evaluation. Routine paraffin embedding offers excellent histological detail. Cryosections provide fresh tissue for histochemical reactions that delineate fiber types and reveal special architectural alterations. Electron microscopy is applied in selected instances to provide diagnostic detail not otherwise apparent. Biochemical analysis of frozen tissue is used to define certain inborn errors of metabolism. This integrated approach allows diagnostic precision far beyond the limited information available from routine paraffin sections. We present examples of diagnoses made possible using these special techniques.

Chronic, slowly progressive neuropathies show grouping of fiber types and target fiber formation, apparent in special histochemical preparations. Routine histological preparations may be normal or show only nonspecific changes. Central core disease shows areas of pallor evident in the central areas of many myofibers in histochemical preparations.

The CD34 antigen is a single chain, heavily glycosylated transmembrane protein originally identified in hematopoietic stem cells. Subsequently it was found to be expressed in cells of normal endothelium and a variety of soft tissue tumors, including: epithelioid sarcoma, solitary fibrous tumor,’ gastrointestinal stromal tumor and dermatofibrosarcoma protuberans. Using paraffin immunohistochemistry, membranous and cytoplasmic staining for CD34 can be seen in these lesions, with most showing a combination of both. The findings of cytoplasmic staining is unexpected, as CD34 is a transmembrane cell surface protein. We analyzed the ultrastructural localization of CD34 on two soft tissue tumors with membranous and combined membranous and cytoplasmic staining.

Biopsy specimens were fixed with a mixture of 4% paraformaldehyde and 1% glutaraldehyde in 0.1M sodium cacodylate buffer, pH = 7.4 for 1-2 hours, and embedded in Poly/Bed 812 with osmium tetroxide post-fixation, or in LR White without osmication. The immunogold method was performed on ultrathin sections placed on Nickel grids,

Pheochromocytoma is a rare tumor found in approximately 2 individuals per million of the population. In 90% of cases, it arises from the chromaffin cells of the adrenal medulla. These cells secrete catecholamines: epinephrine and norepinephrine which have a sympathomimetic action. The classical clinical presentation is paroxysms of extreme elevation of systemic blood pressure. Although pheochromocytoma accounts for only 0.1 % of cases of systemic hypertension, it is important to make the diagnosis, as the sudden release of large quantities of catecholamines into the circulation may prove fatal, as happened in our patient.

We present a case of a 25 year old woman, who collapsed suddenly, while she was feeding her 8 month old baby. She went into ventricular fibrillation and was defibrillated 3 times. There was no response to vigorous resuscitative measures.

Past Medical History: No definitive findings. Vague history of palpitations and an “abnormal heart beat”, which had been considered to be benign.