Comparison of different PCR amplification targets for molecular diagnosis of Strongyloides stercoralis.

Molecular techniques are an alternative for the diagnosis of strongyloidiasis, produced by Strongyloides stercoralis. However, it is necessary to determine the best amplification target for the populations of this parasite present in a geographical area and standardize a polymerase chain reaction (PCR) protocol for its detection. The objectives of this work were the comparison of different PCR targets for molecular detection of S. stercoralis and the standardization of a PCR protocol for the selected target with the best diagnostic results. DNA extraction was performed from parasite larvae by saline precipitation. Three amplification targets of the genes encoding ribosomal RNA 18S (18S rDNA) and 5.8S (5.8S rDNA) and cytochrome oxidase 1 (COX1) of S. stercoralis were compared, and the PCR reaction conditions for the best target were standardized (concentration of reagents and template DNA, hybridization temperature, and number of cycles). The analytical sensitivity and specificity of the technique were determined. DNA extraction by saline precipitation made it possible to obtain DNA of high purity and integrity. The ideal target was the 5.8S rDNA, since the 18S rDNA yielded non-reproducible results and COX1 never amplified under any condition tested. The optimal conditions for the 5.8S rDNA-PCR were: 1.5 mM MgCl2, 100 µM dNTPs, 0.4 µM primers, and 0.75 U DNA polymerase, using 35 cycles and a hybridization temperature of 60 °C. The analytical sensitivity of the PCR was 1 attogram of DNA, and the specificity was 100%. Consequently, the 5.8S rDNA was shown to be highly sensitive and specific for the detection of S. stercoralis DNA.

Premature ageing of the immune system relates to increased anti-lymphocyte antibodies (ALA) after an immunization in HIV-1-infected and kidney-transplanted patients.

Low-affinity immunoglobulin (Ig)G with potential autoreactivity to lymphocytes and hypergammaglobulinaemia have been described previously in HIV-1-infected patients. Whether such antibodies increase after challenging the immune system, for example with an immunization, is not known. In the present study, the modulation of antibodies with low affinity and potential autoreactivity was evaluated after 2012-13 seasonal flu vaccination with a simple empirical laboratory test measuring the titres of anti-lymphocyte antibodies (ALA) in two different models of secondary immunodeficiency: HIV-1 vertically infected patients (HIV) and patients treated with immunosuppressive therapies after kidney transplantation (KT) compared to healthy individuals (HC). In parallel, the activation status of B cells and their degree of immune senescence was evaluated by measuring the B cell interleukin (IL)-21R expression/plasma IL-21 levels and the frequencies of mature-activated (MA) and double-negative (DN) B cells. A significant increase of ALA titres was observed after vaccination in HIV and KT but not in HC, and this correlated directly with the frequencies of both MA and DN and inversely with the B cell IL-21R expression. This suggests that the quality of an immune response triggered by flu vaccination in HIV and KT may depend upon the activation status of B cells and on their degree of immune senescence. Further investigations are needed to verify whether high frequencies of MA and DN may also relate to increase autoimmunity after immunization in high-risk populations.

Ceftaroline as salvage therapy for methicillin susceptible Staphylococcus aureus complicated bacteremia.

Infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) are still associated with significant morbidity and mortality. Treatment failures of cefazolin (CFZ) have been reported and probably related to the inoculum effect. New treatments for severe MSSA infections are needed and ceftaroline fosamil (CPT) could be an option. Our aim was to describe the clinical characteristics of five patients with complicated MSSA bacteremia failing CFZ and successfully treated with CPT. We performed a retrospective chart review in a Hospital in Buenos Aires, Argentina; in a 12-month period, five patients (24%) of 21 with MSSA bacteremia experienced CFZ failure and were salvaged with CPT. The median time of CFZ therapy was 10 days before changing to CPT; four patients had evidence of metastatic spread and 2 had endocarditis. All patients experienced microbiological and clinical cure with CPT, which was used as monotherapy in 4 and in combination with daptomycin in another. One patient discontinued CPT due to neutropenia on day 23 of treatment. In patients with MSSA BSI failing current therapy, CPT could be a good therapeutic option.

Las infecciones causadas por Staphylococcus aureus sensible a la meticilina (SASM) todavía se asocian con una morbilidad y mortalidad significativas. Se han informado fallas en el tratamiento de cefazolina (CFZ) probablemente relacionadas con efecto inóculo. Nuevos tratamientos son necesarios para estas infecciones y ceftarolina fosamil (CPT) podría ser una opción. Nuestro objetivo fue describir las características clínicas de cinco pacientes con bacteriemia por SASM complicada con falla a CFZ y que fueron exitosamente tratados con CPT. Realizamos una revisión retrospectiva de historias clínicas en un hospital de Buenos Aires, Argentina; en un período de 12 meses, cinco pacientes (24%) de 21 con bacteriemia por SASM experimentaron falla a CFZ y fueron tratados con CPT. La mediana de tiempo de la terapia con CFZ fue de 10 días antes de cambiar a CPT; cuatro pacientes presentaban evidencia de diseminación metastásica y 2 tenían endocarditis. Todos los pacientes experimentaron curación microbiológica y clínica con CPT, que se utilizó como monoterapia en 4 y en combinación con daptomicina en otro. Un paciente interrumpió CPT debido a neutropenia el día 23 de tratamiento. En enfermos con infecciones graves por SASM que fallan en la terapia actual, CPT podría ser una buena opción terapéutica.

Efecto condicional de las actitudes hacia pacientes con diagnósticos de salud mental sobre la toma de decisiones en contexto de urgencia según la autopercepción de conocimientos asociados al trabajo con pacientes de salud mental

Introducción: En la actualidad existen pocos estudios con respecto a la evaluación de actitudes y autopercepción de conocimientos de los profesionales de la salud hacia los pacientes con alguna condición de salud mental, y la relación de estas variables con la toma de decisiones respecto de estos pacientes. Desde la experiencia se conoce la dificultad que tienen médicos que no están relacionados con el área de salud mental de afrontar a pacientes con alguna patología psiquiátrica y más aún en las urgencias, ya sea porque reconocen falta de conocimientos del tema, instancias no adecuadas para evaluación además de la alta exigencia de estos servicios. Metodología: El estudio consistió en una encuesta online de carácter transversal aplicada a profesionales de la salud pertenecientes al Hospital Dr. Hernán Henríquez Aravena, ubicado en la ciudad de Temuco, Chile. La encuesta incluyó preguntas sociodemográficas, caracterización de experiencias asociadas a diagnósticos de salud mental, y escalas dedicadas a medir variables (autopercepción, actitudes y toma de decisiones). Resultados: A medida que la autopercepción de conocimientos es mayor, el efecto de las actitudes sobre la toma de decisiones también es mayor. Conclusiones: Tanto las actitudes de los profesionales de la salud hacia este tipo de pacientes, así como su autopercepción de conocimientos, son dos componentes fundamentales para asegurar un buen manejo clínico. Resulta importante que exista un balance en cómo se manejan ambas dentro de un servicio, con el fin de asegurar una atención apropiada y centrada en el bienestar del paciente.

Introduction: Currently there are few studies regarding the evaluation of attitudes and self-perception of knowledge of health professionals towards patients with some mental health condition, and the relationship of these variables with decision making regarding these patients. From experience, its known the difficulty that doctors who are not related to the area of mental health have in dealing with patients with some psychiatric pathology and even more so in emergencies, either because they recognize a lack of knowledge of the subject and instances that are not suitable for evaluation. in addition to the high demand of these services. Methodology: The study consisted of a cross-sectional online survey applied to health professionals belonging to the Dr Hernán Henriquez Aravena Hospital, located in the city of Temuco, Chile. The survey included sociodemographic questions, characterization of experiences associated with mental health diagnoses, and scales dedicated to measuring variables (self-perception, attitudes and decision making). Results: As self-perception of knowledge grows, the effect of attitudes on decision making also increases. Conclusions: Both the attitudes of health professionals towards this type of patients, as well as their self-perception of knowledge, are two fundamental components to ensure good clinical management. It is important that there is a balance in how both are managed within a service, in order to ensure appropriate care focused on the patient's well-being.

Ceftaroline as salvage therapy for methicillin susceptible staphylococcus aureus complicated bacteremia / Ceftarolina como tratamiento de rescate para la bacteriemia complicada por Staphylococcus aureus sensible a la meticilina

Abstract Infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) are still associated with significant morbidity and mortality. Treatment failures of cefazolin (CFZ) have been reported and probably related to the inoculum effect. New treatments for severe MSSA infections are needed and ceftaroline fosamil (CPT) could be an option. Our aim was to describe the clinical characteristics of five patients with com plicated MSSA bacteremia failing CFZ and successfully treated with CPT. We performed a retrospective chart review in a Hospital in Buenos Aires, Argentina; in a 12-month period, five patients (24%) of 21 with MSSA bacteremia experienced CFZ failure and were salvaged with CPT. The median time of CFZ therapy was 10 days before changing to CPT; four patients had evidence of metastatic spread and 2 had endocarditis. All patients experienced microbiological and clinical cure with CPT, which was used as monotherapy in 4 and in combination with daptomycin in another. One patient discontinued CPT due to neutropenia on day 23 of treatment. In patients with MSSA BSI failing current therapy, CPT could be a good therapeutic option.

Resumen Las infecciones causadas por Staphylococcus aureus sensible a la meticilina (SASM) todavía se asocian con una morbilidad y mortalidad significativas. Se han informado fallas en el tratamiento de cefazolina (CFZ) probablemente relacionadas con efecto inóculo. Nuevos tratamientos son necesarios para estas infecciones y ceftarolina fosamil (CPT) podría ser una opción. Nuestro objetivo fue describir las características clínicas de cinco pacientes con bacteriemia por SASM complicada con falla a CFZ y que fueron exitosamente tratados con CPT. Realizamos una revisión retrospectiva de historias clínicas en un hospital de Buenos Aires, Argentina; en un período de 12 meses, cinco pacientes (24%) de 21 con bacteriemia por SASM experimentaron falla a CFZ y fueron tratados con CPT. La mediana de tiempo de la terapia con CFZ fue de 10 días antes de cambiar a CPT; cuatro pacientes presentaban evidencia de diseminación metastásica y 2 tenían endocarditis. Todos los pacientes experimen taron curación microbiológica y clínica con CPT, que se utilizó como monoterapia en 4 y en combinación con daptomicina en otro. Un paciente interrumpió CPT debido a neutropenia el día 23 de tratamiento. En enfermos con infecciones graves por SASM que fallan en la terapia actual, CPT podría ser una buena opción terapéutica.

Respiratory burst and NAD(P)H oxidase activity are involved in capacitation of cryopreserved bovine spermatozoa.

Heparin (a glycosaminoglycan) and quercetin (a calcium-ATPase plasma membrane specific inhibitor) induce bovine sperm capacitation. Mitochondria from frozen semen are capable of generating oxidative energy. The aim of the study was to determine oxygen uptake variation and the participation of diphenileneiodonium (DPI)-sensitive oxidases from spermatozoa capacitated with heparin or quercetin. Oxygen uptake was measured polarographically and 2 microM diphenileneiodonium (DPI) was used as a specific inhibitor of NAD(P)H-oxidases. Sperm capacitation was determined by the chlorotetracycline technique. Heparin produced a respiratory burst (17.0+/-3.2 microL O2/h/10(8) spermatozoa; mean+/-S.D.) versus control (11.3+/-0.9 microL O2/h/10(8) spermatozoa; P<0.05). Oxygen uptake and sperm hypermotility were inhibited by cyanide. Treatment with DPI blocked heparin capacitation and oxygen uptake (cyanide-sensitive) decreased to control levels. Respiration of quercetin-treated samples (cyanide-sensitive; 9.7+/-0.7 microL O2/h/10(8) spermatozoa) was not significantly different from the controls; oxygen uptake was not modified by DPI, but quercetin capacitation was inhibited (P<0.05). The effect of DPI with heparin confirmed that oxidases participate in capacitation induction. The addition of superoxide dismutase and/or catalase to heparin- or quercetin-treated samples, failed to modify oxygen uptake and blocked capacitation (P<0.05), suggesting that the superoxide anion (O2*-) participates in the capacitation induction. High mitochondrial activity from heparin-treated samples indicated that energy requirements, especially for hypermotility, were supported by the respiratory chain. Although a respiratory burst was not produced by quercetin, DPI-sensitive-oxidases (O2*- source) were necessary for capacitation. In cryopreserved bovine spermatozoa, heparin- or quercetin-induced capacitation required different levels of mitochondrial energy and DPI-sensitive oxidase activity.

[Clinicopathological features of solitary fibrous tumors of the pleura: a case series and literature review]. / Tumor fibroso solitario pleural: características clinicopatológicas de una serie de casos y revisión de la bibliografía.

We assessed the clinicopathological features of solitary fibrous tumors of the pleura in a case series comprising 30 patients (20 women, 66.6%) with a mean age of 58.39 years. Forty-five percent of the cases were asymptomatic. In 70% of the cases the tumors arose in the visceral pleura. Twenty percent presented multiple tumors, a finding that was associated with intrapulmonary localization and malignant behavior (P<.0001) Histology revealed low cell density in 15% of the cases, moderate density in 50%, and high density in 35%; further findings showed atypia in 45% of the cases, necrosis in 25%, and hemorrhage in 15%. More than 4 mitoses per 10 high-power fields were noted in 30% of the cases. Immunohistochemistry results were positive for vimentin in all cases; cells were CD34+ in 85% of the cases, BCL2+ in 65%, and CD99+ in 40%. Findings for keratin and protein S100 were negative in all cases. Malignant biological behavior (local recurrence and metastasis) was observed in 4 cases, 2 of which were CD34-. Solitary fibrous tumors of the pleura are uncommon neoplasms with unpredictable biological behavior; follow-up should therefore be based on early detection of recurrence or metastasis.

Polymorphism C242T in the Cyp19 gene in meat sheep.

The objective of this study was to evaluate the frequency of C242T polymorphism on the aromatase gene and the allelic and genotypic frequency of these variants in sheep belonging to four breed groups. Blood samples were collected from 187 animals of four breed groups: Dorper, Santa Inês, Texel and White Dorper, originated from herds in the region of Maringá/PR, Brazil. The genomic DNA was extracted using alkaline extraction, with subsequent amplification of the fragments via PCR with specific primer. The samples resulting from amplification were subjected to digestion process using the Dpn II restriction enzyme and to polyacrylamide gel electrophoresis 10.0% and stained with silver nitrate. Three distinct genotypes were observed: homozygous (CC), heterozygous (CT) and homozygous for no cut (TT). The resulting data were analyzed using the POPGENE software with 5% significance. Genotypic frequencies among the breed groups were: Texel (CC - 0.426; CT - 0.511; TT - 0.064), Dorper (CC - 0.073; CT - 0.732; TT - 0.439), White Dorper (CC - 0.021; CT - 0.255; TT - 0.723) and Santa Inês (CC - 0.115; CT - 0.462; TT - 0.423).

Antigenic profile of human bronchial gland.

Bronchial glands have been regarded as modified salivary glands. It is well known that there no previous reviews concerning the antigenic profile of the bronchial wall. The aim of this study is a systematic survey of the antigenic profile and to describe the histology of normal human bronchial glands. Six formalin-fixed, paraffin-embedded surgical specimens were studied using a panel of 22 polyclonal and monoclonal antibodies by the avidin-biotin-peroxidase method. Bronchial glands disclosed a tubuloacinar structure. The smallest ducts intercalated originated from a cluster of secretory acini and converge to form an excretory duct. No striated duct was observed. Acinar united is composed by mucous, serous and mixed units. Myoepithelial cells are found in relation to the intercalated ducts and secretory acinis. Secretory cells of bronchial glands reacted strongly with cytokeratin AE1 and moderately for CK7, CK18. Additionally, serous acinar cells reacted with AE3, CK19, CK5/6/8/18, CK8/18/19, and Leu7. Myoepithelial cells reacted strongly with a-smooth muscle actin, CD10 and CK34betaE12. Ductal system cells differed from acinar secretory cells in expressing CK34betaE12 and HSP27. In conclusion, the detailed knowledge of the immunohistochemical reactivities of normal cell types of normal human bronchial glands will prove useful in studies of bronchial pathology, especially of neoplastic processes.

Effect of silymarin plus vitamin E in patients with non-alcoholic fatty liver disease. A randomized clinical pilot study.

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized health problem. Various treatment strategies such as thiazolidinediones, metformin, lipid-lowering agents and antioxidants have been evaluated. So far, no single intervention has convincingly improved liver histology. Experience of using silymarin alone or in combination with other agents in patients with NAFLD is limited in the medical literature. The present study was conducted to evaluate the efficacy of silymarin plus vitamin E in the treatment of NAFLD. PATIENTS AND METHODS: A sample of 36 patients was enrolled. The diagnosis of NAFLD was confirmed by percutaneous liver biopsy. All patients were randomized to one of the following intervention groups: group I: treated with 2 tablets per day of silymarin plus vitamin E (Eurosil 85®, MEDAS SL) and a lifestyle modification program consisting of hypocaloric diet (1520 kcal, 52% of carbohydrates, 25% of lipids and 23% of proteins) and exercise for 3 months and group II (only with the hypocaloric diet). Anthropometric variables as waist circumference, weight, body mass index (BMI) were measured. Biochemical parameters: Glucose, triglycerides, AST, ALT, GGt levels and insulin resistance (HOMA-IR) were determined under fasting conditions. Non-invasive NAFLD-index were applied before and after the treatments: Fatty liver index (FLI), liver accumulation product (LAP) and NAFLD-Fibrosis score (FS). RESULTS: The mean age was 47.4 ± 11.2 years old (range 18-67); 22 men and 14 women. In group I, 11 patients (61%) have a NAS-score > 5 and 10 (55.5%) in the group II (NS). Anthropometric parameters decreased after treatment in both groups. Patients in both groups showed a decrease in GGt levels after treatment (group I: 68 IU/L vs. 46.2 ± 27 IU/L; p < 0.05 and group II 80.5 ± 46 IU/L vs. 50.3 ± 27 IU/L; p < 0.05). Only in group II we observed a significant decrease in AST and ALT levels. In both groups, we observed a decrease in: FLI index (group I: 86.2 ± 19 vs. 76.9 + 20; p < 0.05 and in group II: 85.2 ± 18 vs. 77.5 ± 23; p < 0.05), and NAFLD-FS index (group I: -1.6 ± 1.8 vs. -2.1 ± 1.5; p < 0.05 and in group II -1 ± 1.9 vs. -1.5 ± 2.1; p < 0.05). Patients in group I who did not get a 5% loss of weight also displayed decreased GGt levels, and in the FLI and NAFLD-FS indexes; whereas patients in group II without decrease of 5% by weight showed no improvement in any of the analyzed parameters. CONCLUSIONS: Treatment with silymarin plus vitamin E and a hypocaloric diet ameliorate function hepatic test, and non-invasive NAFLD index. Silymarin can be an alternative valid therapeutic option particularly when other drugs are not indicated or have failed or as a complementary treatment associated with other therapeutic programs.

Stabilization of integral membrane proteins in aqueous solution using fluorinated surfactants.

Surfactants carrying either a hydrocarbon or a fluorocarbon alkyl chain have been synthesized. The polar head was either tris(hydroxymethyl)acrylamidomethane (THAM), telomerized THAM, or a glycosylated THAM moiety. The aqueous solubility of some of these molecules was increased by oxidizing to a sulfoxide the thioether function that associates their hydrophobic and hydrophilic moieties. In all cases, the critical micellar concentration was principally determined by the length and chemical nature of the alkyl chain. The usefulness of these surfactants in handling integral membrane proteins in solution has been examined using as test materials chloroplast thylakoid membranes and the photosynthetic complex cytochrome b6f. In keeping with earlier observations in other systems, none of the fluorinated surfactants was able to solubilize thylakoid membranes. Transfer to a solution of fluorinated surfactant of b6f complexes that had been solubilized and purified in the presence of a classical detergent usually resulted in aggregation and precipitation of the protein, while most homologous molecules with hydrocarbon chains did keep the b6f complex soluble. Two of the fluorinated surfactants, however, proved able to maintain the b6f complex water-soluble, intact, and enzymatically active. Because of their limited affinity for lipid alkyl chains and other hydrocarbon surfaces, fluorinated surfactants appear as potentially interesting tools for the study of membrane proteins that do not stand well exposure to classical detergents.

Influence of pH and oxygen on copper corrosion in simulated uterine fluid.

This paper studies the copper corrosion in simulated uterine fluids in the presence of urea and/or albumin, at pH 5.0, 6.3 and 8.0, with 0.10, 0.15 and 0.20 atmospheres of oxygen pressure and without additional oxygen pressure, at 37 degrees C temperature, and for 1, 3, 7, 15, 21 and 30 days experimentation. The copper dissolution rate was determined using absorbance measurements. Copper dissolution was the highest at pH 8.0 and 0.20 atmospheres of oxygen pressure, 674 microg d(-1) for 1 day and 109 microg d(-1) for 30 days. The presence of albumin, contrary to urea, accelerates copper corrosion.

A histopathological study of anoxic-resuscitated liver allografts.

The possibility of resuscitating livers after warm ischaemia has been recently suggested. The aim of the present investigation was to analyse the effects of anoxia on the morphology of hepatic cells, to determine whether these effects are reversible after providing a resuscitation period between warm ischaemia (WI) and cooling, and to study the behaviour of the resuscitated liver in the recipient organism. Ten female, Large-White pigs acted as donors for 10 recipient animals of the same kind who received an orthotopic liver graft. Recipients were divided into two groups depending on whether the livers they received had undergone a resuscitation period (Group I (n=5) where animal livers were subjected to 5 min warm ischaemia (WI) without resuscitation, and Group II (n=5) where the livers were subjected to 5 min WI followed by 5 min resuscitation). Morphological and ultrastructural studies of liver cells were performed using light and electron microscopy. ATP, ADP and AMP levels were determined in liver biopsies by high performance liquid chromatography (HPLC). Plasma AST and bilirubin levels in the two groups were compared 24 h after transplantation. After 5 min of anoxia, hepatocytes showed two morphological patterns in response to WI. Some were appreciably condensed with dark mitochondria, peroxisomes and some cytoplasmic vacuoles. Others showed electronlucent organelles, inflamed mitochondria with broken cristae and disorganized endoplasmic reticulum. Hepatocytes showed globular microvilli and bleb formation with migration towards the sinusoids. One hour after the revascularisation of the resuscitated livers, the hepatocytes showed nearly normal morphological characteristics. However, the hepatocytes of non-resuscitated organs continued to show alterations. Kupffer cells were activated in the livers of both experimental groups. Ultrastructural changes and total tissue adenine nucleotide (TAN) levels recovered completely in resuscitated livers soon after transplant. These results suggest that when short WI periods are followed by equivalent periods of resuscitation, the hepatocytes of transplanted livers recover from the effects of anoxia.

Special operative events in the first case of liver grafting after heart transplantation.

Combined heart-liver transplantation is the only therapeutic possibility for patients with familial hypercholesterolemia IIa. A 12-year-old boy with this metabolopathy underwent a double transplant in two steps (different donors). This original alternative was chosen to assure a safer procedure in this critical situation. Details of intraoperative events are described. Cholesterol and LDL decreased to physiologic levels after liver transplantation. The child's condition is optimal 1.5 years after surgery.

Purification and characterization of BaH4, a hemorrhagic metalloproteinase from the venom of the snake Bothrops asper.

A hemorrhagic metalloproteinase, named BaH4, was isolated from the venom of the snake Bothrops asper by a combination of ion-exchange chromatography on DEAE-Sepharose and gel filtration on Sephacryl S-200. BaH4 is a 69 kDa protein with a pI of 5.3. It was recognized by antibodies raised against hemorrhagic metalloproteinase BaH1 isolated from B. asper venom, with a reaction of partial immunologic identity. BaH4 shows proteolytic activity on biotinylated casein, hide powder azure and fibrin, although having lower activity than crude B. asper venom and metalloproteinase BaP1 isolated from the same venom. BaH4 hydrolyzed fibronectin, laminin and type IV collagen in vitro, albeit at a relatively high enzyme:substrate ratio. Proteolytic activity was inhibited by chelating agents and 2-mercaptoethanol, but not by soybean trypsin inhibitor. Prominent hemorrhage developed in gastrocnemius and cremaster muscles after administration of BaH4. Moreover, it induced lethality in mice after intravenous injection, with an LD50 of 0.37 microg/g. Histological observations showed conspicuous pulmonary hemorrhage when the enzyme was injected intravenously. BaH4 is a hemorrhagic metalloproteinase which may play a relevant role in local and systemic bleeding characteristic of B. asper envenomations.

Phosphorylant capacity study and lactate mitochondrial oxidation in frozen bovine sperm.

Frozen-stored bovine sperm-pellets of proven fertility were used, and the response to respiratory chain effectors was studied, thus demonstrating the energy conservation capacity. It was further observed that the assayed suspensions used lactate oxidatively, which proves the LDH-X mitochondrial activity (the presence of oxidative substrates is fundamental in capacitation and acrosome reaction processes). The suspensions were treated with 10mM phosphate buffer hypotonic medium to eliminate plasmalema and cytoplasmic content. Lactate respiration was sensitive to respiratory chain effectors, such as oligomycin and antimycin. To evaluate the LDH-X contribution to mitochondrial respiration, lipoate dehydrogenase was inhibited through 5-methoxyindole-2-carboxylic acid (MICA) in the presence of pyruvate-malate and citrate-malate, obtaining with the addition of lactate, oxygen uptakes of 18% and 51% with respect to respiration with the mentioned substrates. In the MICA dose-effect curve, a major sensitivity to inhibitor in active state mitochondrial respiration is obtained when pyruvate-malate is used. Lactate competence with pyruvate by mitochondrial LDH-X was observed. The results obtained would allow the thorough study of the necessity of oxidative energy in the capacitation and fertilization processes, and of the LDH-X role in frozen-stored bovine sperm.

IgA reactivity in patients with intestinal or hepatic amebiasis.

The antigens of E. histolytica recognized by IgA antibodies in sera from patients with either amebic liver abscess or intestinal amebiasis, as well as saliva from the latter, were determined in immunoblots of whole native trophozoite proteins. Results show that sera of patients with amebic liver abscess reacted mainly with amebic proteins of more than 200 kDa, whereas those of individuals with intestinal amebiasis recognized a protein of 145 kDa. The saliva of the latter detected a protein of 210 kDa which is not always seen when using the sera of patients with intestinal or hepatic amebiasis.

Copper corrosion-simulated uterine solutions.

We studied the copper corrosion and product layers originating in a simulated uterine solution at pH values 6.3 and 8.0 for 15, 65, 180, and 360 days at 37 degrees C. Absorbance measurements were performed. Corrosion product layers on the copper surface were characterized by scanning electron microscopy, energy dispersive x-ray, and x-ray photo-electron spectroscopy techniques. Copper release for pH 6.3 and 8.0 was 3.4-4.5 microg/day for 15 days and 0.1-0.3 microg/day for 360 days. Of the order of 30%-40% of dissolved cupric ions were trapped in the product layers. The main compounds identified were cuprite (Cu(2)O), calcite (CaCO(3)), and phosphates.

Synthesis and surface-active properties of glycosyl carbamates and thioureas.

Several amphiphilic glycosyl carbamates, glycosyl thiocarbamates and glycosylthioureas were prepared by addition of the anomeric hydroxyl group of acetylated glycosyl derivatives to alkyl isocyanates, or by reaction of glycosyl isothiocyanates with alcohols or amines. The solubility, critical micelle concentrations and detergent efficiency for the extraction of proteins of these compounds were evaluated and compared.

Serodiagnosis of leprosy in patients' contacts by enzyme-linked immunosorbent assay.

Serum samples from 3336 contacts of leprosy patients were tested for antiphenolic glycolipid I antibodies by enzyme-linked immunosorbent assay with the albumin coupled synthetic disaccharide antigen. The overall positivity rate was 9.3%. No significant differences were seen between a group of household contacts of lepromatous patients and those of the other types of the disease. The proportion of ELISA positives was slightly higher in the relatives as compared to workplace contacts and neighbours but significantly different only between the two former (p less than 0.05). Among those contacts with absorbance values higher than 0.100, 5 new leprosy patients were diagnosed, 2 of them with positive skin smears. A sixth contact was detected with a very high absorbance value in whom no single skin lesion was found but whose lepromin reaction was 0 mm and the skin smear showed a bacteriological index of 3+.