DIDS (4,4'-Diisothiocyanatostilbene-2,2'-disulfonate) directly inhibits caspase activity in HeLa cell lysates.

Apoptosis is an important mechanism of cell demise in multicellular organisms and Cl(-) transport has an important role in the progression of the apoptotic volume decrease (AVD). DIDS (4,4'-Diisothiocyanatostilbene-2,2'-disulfonate) is one of the most commonly used Cl(-) transport inhibitors that eliminates or reduces different apoptotic hallmarks such as AVD, caspase-3 activity and DNA fragmentation. DIDS is also a protein crosslinker that alkylates either amino or thiol groups. Since caspases are thiol proteases, our aim was to study whether DIDS could directly inhibit the activity of these proteases. Here, we show that caspase activity induced by 4 h incubation with staurosporine was inhibited by DIDS in HeLa cells that were maintained in the absence of serum for 24 h. Interestingly, the caspase-inhibitory effect of DIDS is downstream to the inhibition of cytochrome c release, suggesting that DIDS might be also acting at the apoptosome. Moreover, DIDS was able to inhibit capase-3, -9, and -8 activities in cell lysates, implying that DIDS can react with and directly block caspases. Our data suggest that antiapoptotic activity of DIDS involves not only inhibition of the voltage-dependent anion channel (VDAC) at the mitochondria and Cl(-) channels at the plasma membrane, but also a third mechanism based on the direct inhibition of caspases.

[Biomarkers for liver fibrosis: advances, advantages and disadvantages]. / Biomarcadores para fibrosis hepática, avances, ventajas y desventajas.

Liver cirrhosis in Mexico is one of the most important causes of death in persons between the ages of 25 and 50 years. One of the reasons for therapeutic failure is the lack of knowledge about the molecular mechanisms that cause liver disorder and make it irreversible. One of its prevalent anatomical characteristics is an excessive deposition of fibrous tissue that takes different forms depending on etiology and disease stage. Liver biopsy, traditionally regarded as the gold standard of fibrosis staging, has been brought into question over the past decade, resulting in the proposal for developing non-invasive technologies based on different, but complementary, approaches: a biological one that takes the serum levels of products arising from the fibrosis into account, and a more physical one that evaluates scarring of the liver by methods such as ultrasound and magnetic resonance elastography; some of the methods were originally studied and validated in patients with hepatitis C. There is great interest in determining non-invasive markers for the diagnosis of liver fibrosis, since at present there is no panel or parameter efficient and reliable enough for diagnostic use. In this paper, we describe the biomarkers that are currently being used for studying liver fibrosis in humans, their advantages and disadvantages, as well as the implementation of new-generation technologies and the evaluation of their possible use in the diagnosis of fibrosis.

Relative bioavailability of isoniazid in a fixed-dose combination product in healthy Mexican subjects.

SETTING: Subtherapeutic plasma isoniazid (INH) concentrations and the development of bacterial resistance may be attributed to poor quality and reduced bioavailability of fixed-dose combination (FDC) formulations. The bioavailability of INH from a generic and that of a branded FDC formulation had not been compared in the Mexican population. OBJECTIVE: To evaluate the bioequivalence of a generic three-drug FDC formulation (3FDC) in comparison with a 3FDC reference with doses of 300 mg INH in 20 healthy Mexican adults, and to generate data regarding the oral relative bioavailability of the drug in this population. DESIGN: A single-dose, randomised-sequence, open-label, two-period crossover study. RESULTS: Both formulations were well tolerated. The pharmacokinetic parameters of INH showed wide inter-individual variability. The average relative bioavailability calculated for maximum serum concentration area under the concentration-time curve (AUC), AUC(0-24h) and AUC(0-∞) of the test 3FDC formulation vs. the 3FDC reference were respectively 64.84% (90%CI 56.01-75.06), 59.05% (90%CI 50.27-69.36) and 57.26% (90%CI 46.93-69.84). CONCLUSIONS: The 3FDC test and reference formulations were not bioequivalent because the 90%CI for the geometric mean ratios did not meet the regulatory requirements for bioequivalence (range 80-125%) based on the rate and extent of absorption.

Size at birth and abdominal adiposity in adults: a systematic review and meta-analysis.

We performed a systematic literature review on the associations between birth size and abdominal adiposity in adults, while also investigating the role of the adjustment for adult body mass index (BMI). MEDLINE, Scopus, Web of Science, LILACS and SciELO databases were searched for articles published up to February 2013. Only prospective studies were included. After screening 2,570 titles, we selected 31 publications for the narrative synthesis, of which 13 were considered to be of high methodological quality. Six main indicators of birth size were identified, and birth weight (BW) was the most extensively studied. Most studies relied on anthropometric measurements as proxies for abdominal fatness or as indicators of body fat distribution. Few studies assessed abdominal adiposity through imaging methods, generally with small sample sizes. Eleven articles could be included in the meta-analyses. BW was found to be positively associated with waist circumference in adulthood, but the association disappeared after adjustment for adult BMI. In contrast, there was no association between BW and waist-to-hip ratio, whereas a strong negative association became evident after controlling for adult BMI. In conclusion, BW seems to be associated with larger adult size in general, including both waist and hip circumferences. The marked change in coefficients after adjustment for adult BMI suggests that post-natal growth strongly affects relative central adiposity, whereas BW per se does not play a role. Given the potential impact of post-natal growth, further research is needed to identify different growth trajectories that lead to abdominal adiposity, as well as studies on interactions of foetal and post-natal growth patterns.

Life-course evidence of birth weight effects on bone mass: systematic review and meta-analysis.

A systematic review of the literature was performed in July 2011. Original papers based on longitudinal studies measuring spine, femoral neck, or total body bone mass by DXA were included (n = 17). Birth weight was positively associated with bone mass among children. The association was unclear among adolescents and weak among adults. This study aims to evaluate the association between birth weight and bone mass in future ages through a systematic review of literature and meta-analysis. A systematic review of the literature was performed in July 2011 in Medline, Web of Science and LILACS bases using key terms: ("birth size" OR "birth weight" OR birthweight OR prematurity OR premature OR "gestational age") AND (osteoporosis OR "bone mass" OR "bone density" OR "bone mineral density" OR "bone mineral content" OR "bone area") AND (longitudinal OR cohort). Original papers based on longitudinal studies measuring lumbar spine, femoral neck or total body bone mass by dual-emission X-ray absorptiometry (DXA) were included. A meta-analysis was performed using birth weight and bone mass density and/or content as continuous variables and adjusted for current height and/or weight. A total of 218 articles were retrieved from which 17 were selected and grouped into three categories according to age: studies with children; with adolescents and young adults, and studies with adults (older than 25). Five papers were included in the meta-analysis. Positive association between birth weight and bone mass was clear among children, unclear among adolescents, and weak among adults. The effect on bone mass content was stronger than those on body mass density regardless of age. Birth weight influences positively bone health in later life. Preventive health policies dealing with early-life modifiable risk factors, as birth weight, should be encouraged to attain an optimal peak bone mass as an strategy to decrease osteoporosis in the elderly.

Relative bioavailability of rifampicin in a three-drug fixed-dose combination formulation.

SETTING: In a previous monitoring study of rifampicin (RMP) in tuberculosis (TB) patients treated with a generic formulation of a three-drug fixed-dose combination (3FDC), very low RMP levels were found. This led us to investigate the bioavailability of the product. OBJECTIVE: To investigate the relative bioavailability of RMP from a generic 3FDC formulation used in the Mexican health care system, in comparison to the reference product, in healthy volunteers. DESIGN: Two-period, two-sequence crossover study. RESULTS: Mean pharmacokinetic parameter values obtained for the test and reference product were respectively 3.13 ± 2.01 µg/ml and 9.95 ± 2.66 µg/ml for peak plasma concentration (C(max)), 15.51 ± 9.77 µg.h/ml and 58.03 ± 16.1 µg.h/ml for area under the concentration (AUC) time curve to the last measurable concentration (AUC(0-12h)) and 17.92 ± 10.66 and 68.43 ± 22.39 µg.h/ml for AUC up to time infinity (AUC(0-∞)). The test/reference ratio of the means (90%CI) was 25.36% (17.33-37.10) for C(max), 21.25% (14.61-30.89) for AUC(0-12h) and 22.08% (15.44-31.56) for AUC(0-∞). These results did not meet the criteria for bioequivalence. CONCLUSION: The test product displayed delayed absorption and markedly inferior RMP bioavailability in comparison to the reference product. RMP-containing generic formulations should only be used if their bioavailability has been evaluated to ensure interchangeability with the reference product and to avoid the risk of markedly inferior RMP exposure through the use of such a product.

[Conjunctival tumors]. / Tumores de la conjuntiva.

Conjunctival tumors are one of the most frequent of the eye and adnexa. They comprise a large variety of conditions, from benign lesions such as nevus or papilloma, to malignant lesions such as epidermoid carcinoma or melanoma which may threaten visual function and the life of the patient. They can arise from any cellular component, but the most frequent are of epithelial and melanocytic origin. Early diagnosis is essential for preventing ocular and systemic spread and to preserve visual function. In this paper we review the clinical characteristics of the most frequent conjunctival tumors, and we discuss tumor management.

[Ocular hypertension as the principal indicator of onset of uveal melanoma]. / Hipertensión ocular como principal forma de presentación del melanoma uveal.

PURPOSE: To present a series of patients with uveal melanoma masquerading as ocular hypertension. METHODS: Patients diagnosed with uveal melanoma were reviewed, selecting those cases with initial presentation as secondary unilateral glaucoma. Clinical and histopathological information useful for prognosis was examined, such as anterior border localization, size and shape of the tumor, associated ocular pathology, cell type and degree of extraocular extension. RESULTS: Seven patients out of a total of 160 diagnosed with melanoma presented with ocular hypertension (4.3% of the total). Six tumors were large, with only one of them being middle-size. All cases had an associated asymmetric cataract on the affected side. Four cases had neovascular glaucoma, two pseudo-phacolytic glaucoma and the remaining case had invasion of the anterior chamber angle. All cases were unresponsive to medical treatment for glaucoma, due to the unsuspected tumor they harbored. Visual acuity was lower than 0.1 in the affected eye in all patients. Only one case had extraocular extension. A histopathologic examination performed in six cases showed that 3 tumors had epithelioid cellularity and also 3 had varying degrees of extrascleral extension. CONCLUSIONS: In patients presenting with the association of unilateral glaucoma and asymmetric cataract, it is crucial to perform imaging studies, such as ultrasound, in order to rule out the presence of an intraocular tumor, and to achieve an early diagnosis, improving the patient's prognosis and the morbidity of treatments.

Hipertensión ocular como principal forma de presentación del melanoma uveal / Ocular hypertension as the principal indicator of onset of uveal melanoma

Objetivo: Presentar una serie de casos de pacientes con melanoma uveal cuya forma de presentación fue la hipertensión ocular (HTO).Métodos: Se revisaron los pacientes con diagnóstico de melanoma uveal seleccionando los casos cuya forma inicial de presentación del tumor fuera un glaucoma unilateral secundario. Se examinaron los datos clínicos e histopatológicos de valor pronóstico como localización del borde anterior, tamaño y forma del tumor, patología ocular acompañante, tipo celular, y grado de extensión extraocular.Resultados: Siete pacientes de un total de 160 diagnosticados de melanoma se presentaron con hipertensión ocular (4,3% del total). Seis fueron melanomas uveales grandes y el restante de tamaño mediano. Todos mostraron una catarata asimétrica en el lado afecto. Cuatro se presentaron con glaucoma neovascular, dos como pseudoglaucoma facolítico y uno con invasión del ángulo de cámara anterior. Todos se encontraban bajo tratamiento médico de glaucoma sin buena respuesta, por no sospecharse hasta ese momento el tumor intraocular. La mejor AV corregida en el ojo afecto fue menor de 0,1 en todos los pacientes. Sólo uno de los casos presentaba extensión extraocular. La histopatología efectuada en seis de los casos mostró 3 tumores de celularidad epitelioide y también 3 con diferentes grados extensión extraescleral.Conclusión: En los pacientes que presenten el cuadro de glaucoma unilateral y catarata asimétrica, es fundamental la realización de técnicas de imagen, como la ecografía, que permitan descartar la presencia de un tumor intraocular, y para realizar el diagnóstico en estadios precoces, mejorando el pronóstico del paciente y la morbilidad de los tratamientos

Purpose: To present a series of patients with uveal melanoma masquerading as ocular hypertension.Methods: Patients diagnosed with uveal melanoma were reviewed, selecting those cases with initial presentation as secondary unilateral glaucoma. Clinical and hystopathological information useful for prognosis was examined, such as anterior border localization, size and shape of the tumor, associated ocular pathology, cell type and degree of extraocular extension.Results: Seven patients out of a total of 160 diagnosed with melanoma presented with ocular hypertension (4.3% of the total). Six tumors were large, with only one of them being middle-size. All cases had an associated asymmetric cataract on the affected side. Four cases had neovascular glaucoma, two pseudo-phacolytic glaucoma and the remaining case had invasion of the anterior chamber angle. All cases were unresponsive to medical treatment for glaucoma, due to the unsuspected tumor they harbored. Visual acuity was lower than 0.1 in the affected eye in all patients. Only one case had extraocular extension. A hystopathologic examination performed in six cases showed that 3 tumors had epithelioid cellularity and also 3 had varying degrees of extrascleral extension.Conclusions: In patients presenting with the association of unilateral glaucoma and asymmetric cataract, it is crucial to perform imaging studies, such as ultrasound, in order to rule out the presence of an intraocular tumor, and to achieve an early diagnosis, improving the patient’s prognosis and the morbidity of treatments

[Ocular presentation in Wegener granulomatosis]. / Presentación ocular de la granulomatosis de Wegener.

CASE REPORT: A 71 year-old female presented with bilateral conjunctivitis, scleritis and peripheral ulcerative keratitis. Ancillary tests showed presence of anti-neutrophil cytoplasmic antibodies, with diffuse granular cytoplasmic immunofluorescence staining (ANCAc). Conjunctival biopsy showed necrotizing vasculitis in small vessels. Diagnosis of Wegener Granulomatosis (WG) was established and upper respiratory affection detected. Treatment with megadoses of cyclophosphamide and corticoids was initiated and remission of the disease was obtained. DISCUSSION: WG is a potentially lethal systemic vasculitis in which ocular involvement may be the first clinical presentation. Scleritis and peripheral ulcerative keratitis indicate systemic involvement, highlighting the importance of prompt diagnosis and treatment.

Follicle-stimulating hormone increases cell proliferation in the ovary and the testis of the chick embryo.

Previous studies have demonstrated that FSH stimulates cell proliferation in the ovary and the testis of the chick embryo. This study analyzed the presence of FSH receptor and the cell subpopulations that proliferate in response to FSH in chick embryo gonads. FSH receptor mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR) in the male and female gonads of the 6 to 14-day-old chick embryo. Somatic cells of the ovary expressed the FSH receptor in the 14-day-old chick embryo. Ovarian surface epithelium of the 14-day-old chick embryo increased the mitotic index 15-18 h after FSH treatment. Similarly, the mitotic index in oogonia was increased 24 h after receiving a pulse of FSH; this result was confirmed by an increase in the number of germ cells that incorporated bromodeoxyuridine (BrdU). Somatic cells of the medullary cords in the ovary displayed an increase in the mitotic index 15-21 h after the FSH injection. In the chick embryo testis, at the same stage of development, the treatment with FSH increased the mitotic index in cells of the seminiferous tubules and to a lesser extent in cells at a peritubular and interstitial location. Present results demonstrate that in the chick embryo, FSH stimulates the proliferation of ovarian surface epithelium, oogonia in the cortex, and somatic cells of the medullary cords of the chick embryo ovary. In the chick embryo testis, FSH stimulates cell proliferation in seminiferous tubules and peritubular cells.

Lectin histochemical study of lipopigments present in the cerebellum of Solanum fastigiatum var. fastigiatum intoxicated cattle.

This study was carried out to investigate the pattern of lectin binding in the cerebellum of calves poisoned with Solanum fastigiatum var. fastigiatum. For the experimental reproduction of the illness, S. fastigiatum var. fastigiatum was collected from farms where the intoxication occurs. The dried ground plant was administered to two 1-year-old cattle by a ruminal cannula. The animals received 5 g/kg b.w. daily, 5 days a week, during periods of 107 and 140 days. After these periods the animals were bled to death. For the histological study, transverse sections of the cerebellum were used. Paraffin-embedded sections were incubated with the following biotinylated lectins with different specificity: Concanavalia ensiformis (Con-A). Glycine max (SBA). Dolichos hiflorus (DBA), Ulex europeus-I (UEA-I). Triticum vulgaris (WGA), succynyl-WGA (sWGA). Arachis hypogaea (PNA), Ricinus communis-I (RCA-I) and Bandeirea simplicifolia-I (BS-I). Avidin-biotin-peroxidase complex was applied as a detection system. Purkinje cells showed vacuolation in the pericaryon. The stored material present in the cells reacted strongly with the following lectins: Con-A. sWGA, WGA and RCA-I. An irregular affinity was observed with PNA and DBA. The lectin-binding pattern was compatible with a glycolipid storage disease.

Congenital cerebellar cortical degeneration in Holstein cattle in Southern Brazil.

A congenital progressive cerebellar disorder is described in Holstein calves. The clinical signs were progressive and were characterized by ataxia, hypermetria, a wide stance and fine head tremors. When the affected cattle were forced to run, the signs were exacerbated, leading to epileptiform attacks. Histological lesions consisted of a very selective cerebellar cortical degeneration, almost exclusively affecting the Purkinje cells. The disease affected 6 out of 200 Holstein calves from the same bull. However, results of mating tests of the bull with his daughters and granddaughters suggested that it was not hereditary (p = 0.0062) although an environmental-genetic interaction could not be ruled out.

Follicle-stimulating hormone regulates steroidogenic enzymes in cultured cells of the chick embryo ovary.

This investigation addresses the potential regulation of enzymes involved in the biosynthesis of steroid hormones during early stages of gonadal development by follicle-stimulating hormone (FSH). Gonadal cells of 10-day-old chick embryo and cells of the left ovary of 18-day-old chick embryo were cultured for 60 h in a defined medium with or without the addition of FSH (2.0 IU/ml). At the end of the culture, cells were recovered and evaluated by biotransformation of tritiated steroid precursors and mRNA levels were evaluated by RT-PCR. The production of estrone from androstenedione was increased in the FSH-treated cells, both human FSH (hFSH) and recombinant human FSH (rhFSH), indicating a stimulatory effect on aromatase (P450arom). Similarly, the intensity of the band corresponding to P450arom mRNA was higher in hFSH and rhFSH than in control and chorionic gonadotropin (hCG) groups. The P450arom stimulation was observed in the ovary of 10- and 18-day-old chick embryo. The transformation of dehydroepiandrosterone to androstenedione was taken as evidence of 3beta-hydroxysteroid dehydrogenase function. This enzyme was stimulated in the cultured ovarian cells of 18-day-old chick embryos treated with hFSH and rhFSH compared with controls. The production of pregnenolone in the mitocondrial fraction of 18-day-old chick embryo ovary was increased when cultured with hFSH and rhFSH. This observation together with the increase in the band intensity corresponding to mRNA of P450 cholesterol side-chain cleavage indicates stimulation by FSH treatment; hCG produced a similar effect. Somatic cells of the medullary cords are proposed to be FSH target cells in the ovary of the chick embryo.

Experimental intoxication by larvae of Perreyia flavipes Konow, 1899 (Hymenoptera: Pergidae) in pigs and some aspects on its biology.

Two pigs were dosed with 5 and 10g/kg bw of fresh Perreyia flavipes larvae collected at the municipality of Pelotas. Two other pigs were dosed with 0.87 and 1.7g/kg of dry P. flavipes (equivalent to 5 and 10g/kg bw of fresh larvae). Another pig was dosed with 0.17g/kg of dry larvae, daily, during 20d. Forty-eight hours after the ingestion, all pigs that ingested single doses showed clinical signs and marked rise in serum aspartate aminotransferase. Alanine aminotransferase and gamma glutamiltransferase were also slightly increased. The pig dosed with 10g/kg of fresh larvae died in 96h. The others recovered in 4-5days after ingestion. No clinical signs were observed in the pigs dosed during 20d with 0.17g/kg of dry larvae. The main lesion observed in the pig dosed whit 10g/kg of fresh larvae was a centrilobular liver necrosis. These results confirmed the toxicity of P. flavipes for swine, demonstrated that the larvae maintain the toxicity after being dried, and suggest no cumulative effect in the larval toxicity. The larvae collected in the field were conditioned in boxes containing swards of native grasses and covered with gauze to prevent the escape of adults on emergence. The larvae pupated from August 11 to September 25. Emergency of adults occurred from February 10 to March 4. Adult females and males live only for 18-36 and 24-48h, respectively. The eggs had an incubation period of 26-33d. The larval period extend from March 1 to August 24.

Experimental intoxication by the mushroom Ramaria flavo-brunnescens in sheep.

Ramaria flavo-brunnescens collected in autumn from 1990 to 1994 was orally administered to 11 sheep. These animals were dosed with 100-430 g/kg bw administered over 3-13 d. Six sheep showed clinical signs and 4 of them died. The mininum toxic dose was of 150 g/kg bw. Clinical signs were anorexia, hyperthermia, dyspnea, polyuria, ataxy, muscle tremors and seizures. The eyes had hyperemia of the sclera and, in some cases, hemorrhages of the anterior chamber or corneal opacity. Sheep dosed with higher doses had ulcerations of the tongue and necrotic lesions in the hooves. The main histologic lesions of the feet and tongue were miopachynsis and endotelial degeneration followed by degeneration, necrosis and ulceration of the epithelium. Hemorrhages of the anterior chamber, and severe congestion and hemorrhages of the iris, ciliary body and process were observed in the eyes. Congestion and perivascular hemorrhages occurred in the central nervous system. The similarity of clinical signs and pathologic lesions induced by R flavo-brunnescens and those caused by ergotism in cattle and sheep suggests the presence ofa vasoactive constrictive substance in the mushroom. Fresh R flavo-brunnescens dosed in autumn 1993 was not toxic at doses of 200-400 g/kg demonstrating variations in the toxicity of the mushroom from year to year.

Patrones de prescripción de antibióticos en atención primaria. ¿Usamos racionalmente los antibióticos en pediatría? / Antibiotic prescribing habits in primary health care. Do pediatricians use antibiotics rationally?

Objetivos: Conocer los patrones de prescripción de antibióticos en la población lactante y preescolar de un centro de salud de la Comunidad de Madrid, así como la necesidad o no de dicho tratamiento y su adecuación a la patología diagnosticada. Métodos : Se realizó un estudio retrospectivo de los procesos infecciosos y respiratorios, así como los ciclos de tratamiento antibiótico recibido, de todos los niños menores de 4 años, durante un año. Se analizó el facultativo prescriptor, así como la adecuación de las decisiones terapéuticas tanto positivas como negativas (sin tratamiento). Resultados Se evaluaron 910 niños de 0-4 años, que presentaron un total de 3.847 procesos infecciosos o respiratorios con una media de 4,55 ñ 3,6 por niño y año. El 63 por ciento de los niños recibió al menos un ciclo antibiótico al año, con una media de 1,63 ñ 1,9 ciclos por niño y año. Se consideraron adecuadas un 85,2 por ciento de las 3.847 decisiones terapéuticas. El 36 por ciento de los procesos recibieron tratamiento antibiótico, lo cual supuso un total de 1.386 ciclos antibióticos. De ellos, el 46,2 por ciento se consideró inadecuado, mayoritariamente (71,6 por ciento) porque no debieron haberse prescrito y los restantes (28,4 por ciento) porque fueron mal elegidos. Hay diferencias entre los facultativos prescriptores, siendo la prescripción más correcta cuando se evalúa al pediatra habitual responsable de la consulta frente a otros médicos fundamentalmente de servicios de urgencias (p < 0,0001). Los antibióticos más utilizados fueron amoxicilina (41,2 por ciento) y amoxicilina-clavulánico (33 por ciento). Las cefalosporinas supusieron un 6,9 por ciento del total. Conclusiones: Se detecta un uso excesivo de antibióticos en la población preescolar que debe ser corregido (AU)