Prevalence of R5 and X4 HIV variants in antiretroviral treatment experienced patients with virologic failure.

BACKGROUND: Antiretroviral therapy (ART) inhibits virus replication. Nevertheless, ART has the disadvantage of generate selective resistance and adverse events. Coreceptor antagonists are a family of antiretroviral drugs that are used with the prior knowledge of patients HIV tropism. OBJECTIVES: The purpose of this work was to estimate the prevalence of R5 and X4 variants among Chilean patients under antiretroviral therapy and virological failure and investigate variables such as plasma viral load (pVL) and CD4 cell count in the population studied. STUDY DESIGN: HIV RNA or proviral DNA was extracted from 454 consecutives patients and tropism testing was performed using a genotypic method performed with Geno2pheno setting a cutoff value for FPR 5.75%. RESULTS: Among 454 individuals analyzed, 299 (66%) harbouring exclusively R5 variants. They not displayed a better clinical profile than individuals harbouring X4 strains (22%). For R5 patients the median of pVL and CD4 cell count were 268,000copies/mL, and 223cells/µL respectively. For X4 samples the values were 368,000copies/mL and 214cells/µL [P>0.05]). Only, 53 patients (12%) could not be analyzed and were categorized as non-reportable. CONCLUSIONS: The genotypic method confirmed that R5 strains were more prevalent despite the fact that patients were treatment-experienced for several years. The genotypic strategy proved to be a faster and cost-effective option as compared to phenotypic assays. According to our results, two of every three patients under antiretroviral therapy and with virologic failure harbour R5 strains, and may be candidates for use of a CCR5 antagonist.

[Papillary carcinoma in a thyroglossal duct cyst: report of two cases]. / Carcinoma papilar en quiste del conducto tirogloso: Reporte de dos casos.

Thyroglossal duct cyst is the most common congenital anomaly of thyroid gland development. However, papillary carcinoma is described only in 1-2% of cases and the clinical appearance is indistinguishable from a benign thyroglossal duct cyst. We report two females aged 15 and 27 years consulting for a cervical mass. In both, a solid cystic lesion was found and excised using the Sistrunk procedure. The biopsy disclosed a papillary carcinoma in both. The postoperative evolution of both patients was uneventful.

Carcinoma papilar en quiste del conducto tirogloso: reporte de dos casos / Papillary carcinoma in a thyroglossal duct cyst: report of two cases

Thyroglossal duct cyst is the most common congenital anomaly of thyroid gland development. However, papillary carcinoma is described only in 1-2 percent of cases and the clinical appearance is indistinguishable from a benign thyroglossal duct cyst. We report two females aged 15 and 27years consulting for a cervical mass. In both, a solid cystic lesion was found and excised using the Sistrunk procedure. The biopsy disclosed a papillary carcinoma in both. The postoperative evolution of both patients was uneventful.

A novel chimeric mitochondrial RNA localized in the nucleus of mouse sperm.

Six identical cDNA clones corresponding to an RNA of 1685 nucleotides that is enriched in mouse sperm compared with testis were isolated from a mouse testis cDNA library. The sequence of these clones corresponds to the 16S mitochondrial RNA plus an inverted repeat of 120 bp covalently joined to the 5' end of the RNA. By RT-PCR, it was demonstrated that this transcript, referred to as chimeric RNA, was present in mouse sperm, testis, liver, kidney, brain, and spleen. The absence of an equivalent sequence in mitochondrial DNA or as a mitochondrial pseudogene in total DNA extracted from sperm, testis, and somatic tissues suggests that the chimeric RNA is a post-transcriptional product, maybe resulting from a trans splicing reaction. The chimeric RNA was found by RT-PCR in total RNA extracted from purified sperm heads. This result was confirmed by in situ hybridization, which showed clear staining of the sperm nucleus with probes corresponding to sequences of the mitochondrial 16S RNA and the inverted repeat.

Mesenchymal stem cells from osteoporotic patients produce a type I collagen-deficient extracellular matrix favoring adipogenic differentiation.

Mesenchymal stem cells (MSCs), precursor cells resident in the bone marrow, have the capacity to differentiate into bone, cartilage, fat, and connective tissue. We have recently reported that MSCs from "healthy" donors differ from cells obtained from osteoporotic postmenopausal women in their proliferation rate, mitogenic response to osteogenic growth factors, and potential to mineralize. The purpose of this study was to examine the factors that explain the differential capacity of MSCs derived from "healthy" control and osteoporotic postmenopausal women to support mineralization. In addition, we examined the factors that regulate the differentiation of osteoporotic cells into adipocytes. For this purpose, we isolated MSCs from bone marrow of donors and analyzed the synthesis and deposition of type I collagen, the main component of bone extracellular matrix, the time course of gelatinolytic activity expression, the deposition of transforming growth factor beta (TGF-beta), and the ability of cells to differentiate into adipocytes. Our results indicate that cells derived from osteoporotic donors synthesized 50% less type I collagen than normal cells and maintained higher levels of gelatinolytic activity under differentiation conditions (70% versus 15% after 14 days in culture). MSCs derived from osteoporotic women produced 60-65% less TGF-beta and expressed higher adipogenic capacity. We conclude that the capacity of MSCs derived from osteoporotic postmenopausal women to generate and maintain type I collagen-rich extracellular matrix is decreased, favoring their adipogenic differentiation. These observations may explain the decreased mineralization previously observed in these types of cells.

Ostomías / Ostomy

En cirugía pediátrica la ostomía desempeña un papel importante en el manejo de determinados cuadros quirúrgicos, influyendo favorablemente en la evolución de ellos hacia la recuperación de mejores condiciones generales y locales que faciliten a futuro cirugías de mayor envergadura

[Peroxide metabolism on respiratory muscles: effect of growth, maturation and aging]. / Metabolismo de peróxidos en músculos respiratorios: efecto del crecimiento, desarrollo y envejecimiento.

BACKGROUND: Glutathione peroxidase (GSHPx) and catalase are two important cellular antioxidant enzymes involved in H2O2 and lipid-peroxide metabolism. AIM: To study the effects of growth, maturation and aging on the activity of these enzymes. MATERIAL AND METHODS: GSHPx and catalase specific activities were measured in samples of diaphragm and intercostal muscle of male Sprague-Dawley rats of different ages (21, 50, 70, 180 and 365 days), anesthetised with chloral hydrate (45 mg/100 g i.p.). RESULTS: The diaphragm and intercostal muscles did not differ in GSHPx activity at 21 days. After that, GSHPx activity increased progressively with age, but following a different pattern, in each muscle, suggesting an increase in enzyme substrates with age. In one year old animals, GSHPx activity was 5 times higher for the diaphragm and 3 times higher for the intercostal muscles, when compared with values observed at 21 days of age. Catalase activity also increased with age in the diaphragm but not in the intercostal muscles. CONCLUSIONS: GSHPx activity increases progressively with age in rat respiratory muscles, with a time course that is specific of each muscle. Catalase activity increases with age only in the diaphragm. These results support the hypothesis that antioxidants in respiratory muscles undergo specific regulatory changes with age.

Estudio del ganglio centinela en melanoma maligno: descripción de la técnica y resultados iniciales / Sentinel lymph node malignant melanoma: description of the technic and first results

El manejo profiláctico de los linfonodos regionales en melanoma maligno es un tema controversial. En la actualidad, se reconoce la utilidad de la identificación del primer linfonodo de drenaje a la lesión (ganglio centinela) para definir la conducta respecto a la linfadenectomía profiláctica. La identificación de este ganglio se realiza con los mejores resultados, utilizando la cintigrafía asociada a la tinción con azul de metileno en el intraoperatorio. Se evaluaron nueve pacientes, seis mujeres y tres hombres, con un promedio de edad de 48 años, con lesiones en estadio I y II distribuidas topográficamente de la siguiente forma: extremidad inferior 4, extremidad superior 1, torso 2 y cabeza y cuello 2. Los resultados iniciales del estudio demuestran la validez y la aplicabilidad de la técnica, la que puede producir cambios significativos en el manejo de estos pacientes. El escaso número de pacientes, impide obtener conclusiones con significación estadística en este momento del estudio

Comparación de digoxina y enalapril en insuficiencia cardíaca secundaria a insuficiencia mitral / Comparison of the effects of digoxin or enalapril in the treatment of heart failure due to mitral insufficiency

Background: There is not much evidence about the usefulness of digoxin or enalapril in the treatment of heart failure due to mitral insufficiency. Aim: to compare digoxin and enalapril in the treatmen of heart failure due to mitral insufficiency. Patients and methods: Patients with mitral insufficiency, in sinus rhythm, with a heart failure grade II or III and with echocardiographic left ventricular dilatation were eligible for the study. They received sequentially, during 12 weeks each, digoxin 0.25 mg/day or enalapril in doses up to 20 mg/day, with a washout in-between period of 2 weeks. The order of the sequence was determined randomly. At the start and end of treatment, functional class according to NYHA and maximal exercise tolerance in the treadmil were assessed and a color Doppler echocardiogram was done to measure ventricular dimensions, function and degree of mitral insufficiency. Results: Nine patients on enalapril and 12 on digoxin improved their functional capacity. Digoxin improved exercise time in 76ñ168 sec (p= 0.022), whereas this change was not significant with enalapril (38ñ158 sec; p= 0.2). With enalapril treatmen, ventricular diastolic dimensiondecreased from 59.3ñ8.1 to 58ñ9.3 mm and the area of mitral insufficiency decreased from 8.1ñ3.5 to 6.6ñ3.1 cm2. Digoxin did not induce any significant echocardiographic change. Conclusions: In these patients, digoxin and enalapril improved functional class. Digoxin improved exercise time and enalapril reduced ventricular dimensions and mitral insufficiency

El niño fisurado: un problema multidisciplinario / The fissured children: a multidisciplinary problem

El niño que nace con una fisura labiopalatina lleva consigo una malformación compleja cuya corrección implica diversos tratamientos, los que deben ser realizados por múltiples especialistas, con un resultado alentador en el largo plazo. La lesión compromete varias estructuras, de ahí su gravedad y su complejidad. En nuestro país ocupa el 4º lugar de las malformaciones congénitas en el recién nacido. En Chile, en la evolución histórica de su tratamiento destaca con nitidez lafigura del Dr. Alfredo Gantz Mann, cirujano pediatra que desarrolló programas terapéuticos en el Hospital Roberto del Ríoy en la Clínica Alemana de Santiago. Es de reconocimiento público su esforzado labor pionera asistencias y docente

Identification of reactive conserved histidines in phosphoenolpyruvate carboxykinases from Escherichia coli and Saccharomyces cerevisiae.

Escherichia coli and Saccharomyces cerevisiae phospho enol pyruvate (PEP) carboxykinases are inactivated by diethylpyrocarbonate (DEP). Inactivation follows pseudo-first-order kinetics and exhibits a second order rate constant of 0.8 M-1 s-1 for the bacterial enzyme and of 3.3 M-1 s-1 for the yeast carboxykinase. A mixture of ADP + PEP + MnCl2 protects against inactivation by DEP, suggesting that residues within the active site are being modified. After digestion of the modified proteins with trypsin, the labeled peptides were isolated by reverse-phase high-performance liquid chromatography and sequenced by Edman degradation. His-271 of E. coli carboxykinase and His-273 of the yeast enzyme were identified as the reactive amino-acid residues. The modified histidine residues occupy equivalent positions in these enzymes, and they are located in a highly conserved region of all ATP-dependent phospho enol pyruvate carboxykinases described so far.

Registro continuo por 24 horas de pH esofágico en niños / Continuous registration by 24 hours of esophageal pH in children

Se describen los resultados del registro continuo, por 24 h de pH esofágico en 24 pacientes con reflujo gastroesofágico, 14 de ellos mujeres, de 5,8 años (1 a 14) años de edad cuyo diagnostico se sustentaba en bases clínicas, radiológicas o endoscópicas. Se empleó un sistema de registro Digitrapper Mark II Gold y un sistema de valoración de las variables Boix-Ochoa o de DeMeester, según la edad del paciente. Se registraron el número total de reflujos, los de más de 5 min de duración, el episodio más largo de reflujo, el tiempo de exposición de la mucosa al ácido (TTR), el porcentaje de tiempo total de reflujo, se calculó el puntaje final según DeMeester y el índice de síntomas en relación al reflujo. El estudio fue bien tolerado en todos los casos. Sólo en dos pacientes (8,3 por ciento) los resultados fueron normales, en los 22 restantes (91,7 por ciento) se registraron alteraciones en alguno de los criterios analizados. Las medias de los registros obtenidos fueron: número total de reflujos 94; número de episodios de reflujos mayores de 5 minutos 2; total de pH inferior a 4 fue 65 minutos y porcentaje del tiempo total de reflujo 5,4 por ciento

Comparación de digoxina y atenolol en fibrilación auricular crónica / Comparison between digoxin and atenolol in chronic atrial fibrillation

The benefits of digoxin in patients with atrial fibrillation may be reduced due to its limited effect on atrioventricular conduction. The aim of this work was to compare digoxin and etanolol on functional class, resting and exercise heart rate and exercise capacity in patients with atrial fibrillation. Thirteen subjects with this condition, normal echocardiographic left ventricular function and size, a resting heart rate less than 80 beats/min and with no contraindication for beta blocker or digoxin use, were studied. Patients were randomly assigned to receive initially digoxin 0.25 mg. o.d. or atenolol 100 mg o.d. in a double blind fashion. The doses were sdjusted to obtain a heart rate between 60 and 80 beats-min at the end of the first week of treatment. After 2 weeks of treatment, outcomes were assessed, patients were left without treatment for one week and crossed over to the other drug after that. Resting heart rates achieved with digoxin and atenolol were similar (67ñ11 and 65ñ23 beats/min respectively). However, maximal exercise heart rates and maximal exercise time were higher during digoxin treatment (166ñ23 vs 135ñ27 beats/min and 9.95ñ1.68 vs 8.5ñ2 min respectively). NYHA functional class deteriorated in 3 patients receiving atenolol. We conclude that atenolol achieves a better control of heart rate during exercise but also reduces maximal exercise capacity

La digoxina es efectiva en el tratamiento de pacientes con insuficiencia cardíaca y ritmo sinusal / Digoxin is effectiveness in the treatment of cardiac failure and sinus rhythm patients

Due to differences in treatment effect in studies on the effectiveness of digoxin in patients with congestive heart failure in sinus rhythm, a cross-over placebo-controlled randomized double blind clinical trial was performed. Thirty one patients, without previous treatment with digoxin, in New York Heart Association (NYHA) functional class II to IV, with a dilated left ventricle and/or ventricular systolic dysfunction were included. Patients received digoxin, adjusted for blood levels, or placebo, during an 8 week period, prior to crossing over to the other treatment for another 8 weeks. The order of tretments was randomly allocated. Outcome measurement were performed at the end of each 8 week period. Digoxin, compared with placebo, improved NYHA class, 6,9 por ciento vs 41.4 por ciento (p=0.013) and increased the treadmill exercise time, 406 ñ 204 s vs 484 ñ 185 s (p=0.003). During the digoxin treatment the left ventricular and systolic diameter was reduced from 52.9 ñ 8.9 to 50.1 ñ 9.7 mm (p=0.009). No significant difference was observed in the left ventricular end diastolic diameter (LVED) of the left ventricle and in a estimation of quality of life. In conclusion, digoxin treatment produced a significant improvement in functional capacity, exercise time and left ventricular performance

Test de TRH en spray nasal / TRH test by nasal spray

Se estudió la utilidad clínica del test de TRH por vía nasal. Luego de la obtención de muestras basales se administró una dosis de 1 mg de TRH en cada fosa nasal y tanto la respuesta hiposifisiaria (TSH y PRL) como tiroidea (T4) a los 30 y 60 min. fueron analizadas en 12 pacientes, 6 normales 6 portadores de una Tiroiditis Crónica con disminución de la reserva Tiroidea. El grupo control presentó un peak de TSH a los 30 min que no superó los 25 uUl/ml (13.7 ñ 2.9 u Ul/ml) y de PRL de 68.9 ñ 4.3 ng/ml. Los 6 pacientes con una Tiroiditis Crónica, la respuesta TRH fue claramente mayor con un valor máximo de TSH de 43.5 ñ 4.4 uUl/ml y de PRL de 112 ñ 8 ng/ml a los 30 min. Se concluye que la administración de TRH por vía nasal es capaz de inducir una respuesta hipofisiaria tanto de los tirotropos como en los lactotropos, similar a la que se observa con TRH endovenoso

Atención integral del niño fisurado en la IX región (Temuco-Chile) / Comprehensive child care of cleft palate at the IX region (Temuco-Chile)

Se describre la experiencia de un equipo multidisciplinario de tratamiento para NF Labiopalatinos en la IX Región, entre 1980 y 1986, en 250 NF de ambos sexos, portadores de diversos tipos de fisuras en las que predominan las formas más complejas de lesión. Se expone un algo-ritmo de trabajo organizado integral el que es necesario para dar al NF la mejor atención. Se comenta el apoyo de gran valor de entidades comunitarias benéficas (local: COANIFIS e internacional: INTERPLAST) en el tratamiento completo, complejo y de alto costo en estas patologías