High performance liquid chromatography (HPLC) of antibiotics of vancomycin type. Comparative studies.

Comparative HPLC examination of seven antibiotics of vancomycin type has been undertaken. Investigation has shown that on column I in eluent system B, ristomycin A (ristocetin A) can be not only separated from vancomycin, but both antibiotics can be quantitatively determined. Under these conditions the lowest detectable quantities of the individual antibiotics have been also stated. By the application of this column and eluent system A, ristomycin A (ristocetin A) and the major component of the A-35512 B antibiotic complex can be readily separated from one-another and from avoparcin alpha and beta.

[Trichophyton simii in a "Caí" monkey (Cebus apella) colony in the province of Corrientes, Argentina.]. / Trichophyton simii en una colonia de monos "Caí" (Cebus apella), en la provincia de Corrientes, Argentina.

The objective is to describe an outbreak of Trichophyton simii in a Cebus apella monkey colony in Argentine. During summer, alopecic zones appeared on dorsal regions from head to base of the tail of the animals. The hair and skin of nine animals were streaked onto Sabouraud dextrose with cloramphenicol and incubated at 25 degrees C. By the 10th day, white, filamentous colonies, which turned pale pink, developed from simples of four animals. Microscopical examinations were carried out and, because of colony and macroconidia morphology, were classified as Trichopyton simii. Although infection with T. simii is considered a zoonosis, we did not find human cases.

Effects of high molybdenum intake on 1,2-dimethylhydrazine-induced intestinal tumors in rats.

Wistar male rats, 3 months of age were given ad-libitum a nutritionally adequate diet and demineralized drinking water. The Molybdenum (Mo) and Tungsten (W) were provided in the drinking water at 200 ppm concentration. Intestinal tumors were induced by 1,2-dimethylhydrazine (DMH) given subcutaneously as 16 weekly doses at 20 mg/kg body weight. Mo in the form of (NH4)6 Mo7O24 4H2O or W in the form of (Na2WO4) were provided in the drinking water two months before the first DMH treatment and were continued during 4 months more until the last DMH treatment. Three months after the last carcinogen injection, all animals were sacrificed and examined for intestinal tumors. The number, size and location of the tumors were recorded and the pathology was examined. The addition of Mo to the drinking water induced an increase of hepatic Mo content. At the end of the second month, the hepatic content of Mo was 5.61 ppm, compared with control and W groups (2.18 and 0.96 ppm, respectively). A significantly lower incidence of tumors was observed in the Mo group (47), compared with the control group given DMH alone (105) and W group (113). On the other hand, the Mo group showed a significant decrease in the numbers of multiple tumors per rat.

Histopathological characterization of nephritides in the brown capuchin monkey, Cebus apella (Primates: Cebidae).

The renal lesions are of special importance in the captive primates. The most commonly pathologies are: pyelonephritis, nephrocalcinosis, glomerulonephritis, congenital malformations, hydronephrosis and functional diseases. We report the histopathological study of renal lesions of five cases of deaths in Cebus apella (Primates) of the Argentinean Primate Center. The ages of the monkeys were from 4 months to 15 years old. Microscopically, we have observed principally acute diffuse proliferative glomerulonephritis, hilar mesangio proliferative glomerulonephritis, extracapilar glomerulonephritis with crescents, chronic interstitial nephritis and chronic pyelophritis.

[Erythema elevatum diutinum]. / Erythema elevatum diutinum.

Three cases of Erythema Elevatum Diutinum are reported and a revision of the literature about this subject is made. The authors described extensively the general and cutaneous clinical picture. They precise the histological characteristics and mention other dermatological proceses from which this entity must be differentiated. Finally the ethiology and treatment of this clinical picture are discussed.

[Epidermotropic reticulosis (Woringer-Kolopp disease)]. / Reticulosis epidermotrópica (enfermedad de Woringer-Kolopp).

The Woringer-Kolopp's disease must be considered a clinical-pathologic variant of mycosis fungoides. It is characterized by heterogenous clinical features and a peculiar histological aspect given by the cellular infiltration of the epidermis. The orgin of the reticular elements is discussed. Though some investigators think they originate in the dermis, others consider their origin to be "in situ". The evolution and prognosis are not well defined, as is the case with the hyperplastic, heteromorphic and polymorphic reticuloses. The case presented has had Hodgkin's disease and then developed a picture of pagetoid reticulosis.

Substance P receptor antagonist reverses intestinal pathophysiological alterations occurring in a novel ex-vivo model of Cryptosporidium parvum infection of intestinal tissues derived from SIV-infected macaques.

BACKGROUND: Cryptosporidium infection leads to life-threatening diarrhea in AIDS patients. Pathogenesis of cryptosporidiosis is due to intestinal physiological alterations. We devised an ex-vivo model using ex-vivo Cryptosporidium parvum infection of jejunal tissues derived from SIV-infected macaques and studied the role of substance P (SP) in the pathogenesis of cryptosporidiosis. METHODS: We measured jejunal SP protein levels using ELISA, and electrophysiological alterations using the Ussing chamber technique in an ex vivo model of Cryptosporidium infection. Paraformaldehyde-fixed jejunum from SIV-infected macaques with and without naturally occurring cryptosporidiosis was studied for SP protein expression by immunohistochemistry and fluorescence deconvolution microscopy. RESULTS: Ex-vivo Cryptosporidium-infected tissues and tissues from SIV-infected macaques with naturally occurring cryptosporidiosis demonstrated elevated SP protein levels compared with tissues from SIV-infected animals without ex-vivo C. parvum infection or tissues from SIV-infected animals that have no evidence of cryptosporidiosis. In our ex-vivo model of Cryptosporidium infection, we demonstrated pathophysiological alterations that were blocked by SP-receptor antagonist treatment. CONCLUSIONS: These studies suggest that SP-receptor antagonists could prove useful for treatment of AIDS-related cryptosporidiosis.

Aortic aneurysm in a Cebus apella monkey with experimentally induced atherosclerosis.

The sudden death of a Cebus apella female (> 19 years old) on an experimental hyperlipidic diet during three years is described. The gross lesions were hemothorax, atherosclerotic plaques in the aortic curve, and an aneurysm in the ascending aorta. Histologically, an enlargement of the intima in the ascending aorta with hyalinization and a thrombus were observed. The media was thinned and showed sclerosis and hemorrhage extending to the tunica adventicia.

Spontaneous hepatocellular carcinoma in Saimiri boliviensis.

Hepatocellular carcinomas are rare in nonhuman primates. In this study we found the first naturally occurring hepatocellular carcinoma in a Squirrel Monkey (Saimiri boliviensis) of at least 24 years of age. In the necropsy, the liver was cirrhotic and contained multiple tumorous nodules, which varied in diameter from 3 to 15 mm. The lungs also contained small neoplastic masses. In the histological study, samples of liver, lungs, and other organs were taken and fixed in 10% buffered formalin, embedded in paraffin, cut at 5 microns, and colored with hematoxylin and eosin. The histological study of the liver permitted the detection of multiple masses of neoplastic liver cells in a closely packed trabecular configuration surrounded by a well-developed capillary basement membrane. Cirrhotic changes also were observed in the liver. The histological study of the lung confirmed the metastasis of the hepatocellular carcinoma. Metastasis was not found in other organs.

Glomerular lesions in renal biopsies of Saimiri boliviensis (primate) examined by light and electron microscopy and immunohistochemistry.

In order to determine the existence of glomerular lesions in Saimiri boliviensis, renal biopsies were performed in 20 clinically healthy animals of similar age and both sexes. Biopsies were obtained by laparotomy with a Tru-Cut biopsy needle. Mesangioproliferative glomerulonephritis characterized by an increased number of mesangial cells and increased mesangial matrix was present in 35% of the animals. Proliferative glomerulonephritis characterized by increased numbers of epithelial and endothelial cells with narrowed capillary lumen, and membranous glomerulonephritis characterized by diffuse thickening, wrinkling, and occasional lamellation of basement membranes, were present in 15% of the samples. Ultrastructural features included increased mesangial matrix, fusion of the visceral epithelial foot processes, thickened glomerular basement membranes, and incipient lamellation. Immunohistochemical examination revealed granular deposits of immunoglobulin M in the cytoplasm of mesangial cells and in the mesangial matrix in 50% of the samples.

[Histological and histochemical study of hyperplastic and dysplastic lesions of the large intestine in Cebus Apella (primate) treated with 1,2-dimethylhydrazine]. / Estudio histológico e histoquímico de lesiones hiperplásicas y displásicas del intestino grueso en Cebus apella (primate) tratado con 1,2-dimetilhidrazina.

The main objective of this study was to assess the histological changes of colon ephitelium in Cebus apella induced by 1,2-dimethylhydrazine (DMH) administration. Twelve monkeys, males, (aged x: 30 months) with an average body weight of 2,800 g were utilized. The DMH was injected subcutaneously at 25 mg/kg and continued once a week for 16 weeks. The body weight was assessed once a week during the first 4 months and every 30 days until the end of the experience. Histological changes of intestinal ephitelium and mucins were assessed at the end of the experience in specimens sectioned at 5 microns, stained with Haematoxylin and Eosin, PAS and Alcian blue pH 2.5. The histological and histochemical study permitted to characterize the normal morphology, as well as the mucins characteristics in the three regions: caecum, transverse colon and distal colon. The histological changes in the DMH treated animals were hyperplasia, dysplasia and mucins decreasing. The hyperplastic changes were localizated in glandular crypts, and in the epithelio located over the lymphoid nodules. The dysplastic crypts were observed in the transverse colon and in the last portion of distal colon. These lesions were located in the upper portion as well as the bottom of the mucosa. A decrease of neutral and acids mucopolysaccharides were observed in the crypts. The results of this study suggest that the DMH induced hyperplastic changes in the crypts and in the epithelium located over the lymphoid nodules and dysplastic focus, as well as a decrease of neutral and acids mucopolysaccharides.

Failure to induce tumors in the large intestine of Capuchin mokeys (Cebus apella) by using 1,2-dimethylhydrazine.

The purpose of this study was to produce tumors in the large intestine of Capuchin Monkeys (Cebus apella) by the administration of the colonotropic carcinogen 1,2-dimethylhydrazine (DMH). The subjects were 12 monkeys, all males, age 30 months, with a mean weight of 2.858 kg. The DMH was administered subcutaneously to six of the monkeys at a dosage of 25 mg/kg of body weight once a week for 16 weeks; control monkeys received an equivalent volume of the stock solution without DMH. Twenty months after administration of the first dose, the animals were sacrificed. None of the monkeys showed intestinal tumors. Samples of the gastrointestinal tract were removed, fixed, and stained according to standard histological techniques. Histological changes were seen in all of the DMH-treated animals; these consisted of glandular hyperplasia and hyperplasia of the epithelium overlying the lymphoid nodules. In addition, foci of dysplasia were found in three of the animals. Our results suggest that the DMH induced pre-neoplastic changes, characterized by hyperplasia and dysplasia, in the mucosa of the large intestine.

[Description of the external morphology of Duboisiella proloba Baer, 1983 (Trematoda: Strigeida) from Didelphis albiventris in argentina, by scanning electronic microscope]. / Descripción de la morfología externa de Duboisiella proloba Baer, 1938 (Trematoda: Strigeida) de Didelphis albiventris en Argentina, por microscopía electrónica de barrido.

The aim of this study was to report some external morphological features of Duboisiella proloba Baer, 1938. The parasites were collected during necropsy from the small intestine of Didelphis albiventris hunted in its native environment near Corrientes City, Argentina. Collected specimens of Duboisiella proloba were observed by light microscopy in order to be classified. Later the parasites were put into a 3% glutaraldehyde solution, dehydrated, dried by critical point, assembled, metallized, observed and photographed with a SEM. This is the first description of some external morphologic features of this species carried out by SEM in Argentina.

Immunoglobulin-A nephropathy with crescentic glomerulonephritis in a pigtailed macaque (Macaca nemestrina).

A 4-year-old female pigtailed macaque (Macaca nemestrina), experimentally coinfected with simian immunodeficiency virus (SIVmac251) and Mycobacterium bovis(bacillus Calmette-Guerin), was euthanatized 1 year after infection because of weight loss and labored breathing. On gross examination, both kidneys were found to be markedly enlarged (right: 54.7 g and left: 51.7 g; normal < 20 g). Renal lesions were evaluated by histopathologic, immunohistochemical, and ultrastructural methods. Light microscopy revealed that the glomeruli were diffusely hypercellular with expansion of the mesangial matrix, and crescent formation affected approximately 60% of the glomeruli. By immunohistochemical evaluation, it was found that the crescents were composed principally of macrophages, as seen by CD68 (KP1), MRP8, MAC387, and HAM56 expression. Electron microscopic examination of the glomeruli revealed extensive intramembranous, subendothelial, and mesangial electron-dense deposits and multifocal fusion of the visceral epithelial foot processes. Immunofluorescence, used to determine the composition of the electron-dense deposits, revealed diffuse granular mesangial and capillary staining for immunoglobulin A (IgA). The renal changes described in this case report are most consistent with the findings of crescentic gloerulonephritis with IgA immune complex deposition in the glomerular basement membrane and mesangium as described in humans with IgA nephropathy.

[Immunological studies on patients with mycosis fungoides]. / Estudios immunológicos efectuados en pacientes con micosis fungoide

Recently, much has been published on the immunological status of patients affected with various lymphomas. In the particular case of Mycosis fungoide, there was no general agreement on the immunological status of the corresponding patients. In fact, López Borrasca et al, found severe depression of cellular immunity in such patients. On the contrary, Blaylock and Clendenning found very little change in cellular immunity, but a very high serum-IgA. We want to offer our experience on this problem with the immunological survey of four patients with the Alibert-Bazin-form of Mycosis fungoide. The following tests were performed on each patient: a) Intracutaneous test with candidina, PPD and other bacterial antigens. b) Sensitization to a concentrate solution of dinitrochlorobencene (DNCB). c) Lymphocyte Transformation Test (LTT), with phytohemagglutinin as mitogen. d) Quantitative determination of IgG, IgM, IgA and beta1C, with the radial immunodiffusion technique (Mancini et al.). e) Agar immunoelectrophoresis. The following results were obtained: 1) The cellular immunity was markedly depressed in the four patients when any of a, b or c-test was performed. 2) All the patients showed very high levels of serum IgA, 150% higher than control. The reason for this is unknown. On the contrary, IgG in serum was less elevated and IgM and beta1C serum levels were normal. 3) No monoclonal bands were found in any case (immunoelectrophoresis). 4) No definite conclusions could be reached due to the limited number of cases, but the uniformity of results should encourage to carry this work further.

[Spontaneous and simultaneous external and internal double biliary fistula]. / Doble fístula biliar interna-externa espontánea simultánea.

An exceptional case is presented of double biliary fistula, internal (to duodenum) and external (to the abdominal wall) in a patient with cholelithiasis of long evolution. The diagnosis of suspicion was made by CAT and was confirmed in the surgical act. Treatment was cholecystectomy, closure of the duodenal communication and external drainage of the parietal abscess. The postoperative evolution coursed without complications.