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1.
Mol Biol Evol ; 36(8): 1831-1842, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31062861

RESUMEN

Estimating multiple sequence alignments (MSAs) and inferring phylogenies are essential for many aspects of comparative biology. Yet, many bioinformatics tools for such analyses have focused on specific clades, with greatest attention paid to plants, animals, and fungi. The rapid increase in high-throughput sequencing (HTS) data from diverse lineages now provides opportunities to estimate evolutionary relationships and gene family evolution across the eukaryotic tree of life. At the same time, these types of data are known to be error-prone (e.g., substitutions, contamination). To address these opportunities and challenges, we have refined a phylogenomic pipeline, now named PhyloToL, to allow easy incorporation of data from HTS studies, to automate production of both MSAs and gene trees, and to identify and remove contaminants. PhyloToL is designed for phylogenomic analyses of diverse lineages across the tree of life (i.e., at scales of >100 My). We demonstrate the power of PhyloToL by assessing stop codon usage in Ciliophora, identifying contamination in a taxon- and gene-rich database and exploring the evolutionary history of chromosomes in the kinetoplastid parasite Trypanosoma brucei, the causative agent of African sleeping sickness. Benchmarking PhyloToL's homology assessment against that of OrthoMCL and a published paper on superfamilies of bacterial and eukaryotic organellar outer membrane pore-forming proteins demonstrates the power of our approach for determining gene family membership and inferring gene trees. PhyloToL is highly flexible and allows users to easily explore HTS data, test hypotheses about phylogeny and gene family evolution and combine outputs with third-party tools (e.g., PhyloChromoMap, iGTP).


Asunto(s)
Evolución Biológica , Genómica/métodos , Filogenia , Programas Informáticos , Mapeo Cromosómico , Cilióforos/genética , Codón de Terminación/genética , Familia de Multigenes , Homología de Secuencia , Trypanosoma brucei brucei/genética
2.
mSystems ; 5(2)2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32156798

RESUMEN

Soil ecosystems harbor diverse microorganisms and yet remain only partially characterized as neither single-cell sequencing nor whole-community sequencing offers a complete picture of these complex communities. Thus, the genetic and metabolic potential of this "uncultivated majority" remains underexplored. To address these challenges, we applied a pooled-cell-sorting-based mini-metagenomics approach and compared the results to bulk metagenomics. Informatic binning of these data produced 200 mini-metagenome assembled genomes (sorted-MAGs) and 29 bulk metagenome assembled genomes (MAGs). The sorted and bulk MAGs increased the known phylogenetic diversity of soil taxa by 7.2% with respect to the Joint Genome Institute IMG/M database and showed clade-specific sequence recruitment patterns across diverse terrestrial soil metagenomes. Additionally, sorted-MAGs expanded the rare biosphere not captured through MAGs from bulk sequences, exemplified through phylogenetic and functional analyses of members of the phylum Bacteroidetes Analysis of 67 Bacteroidetes sorted-MAGs showed conserved patterns of carbon metabolism across four clades. These results indicate that mini-metagenomics enables genome-resolved investigation of predicted metabolism and demonstrates the utility of combining metagenomics methods to tap into the diversity of heterogeneous microbial assemblages.IMPORTANCE Microbial ecologists have historically used cultivation-based approaches as well as amplicon sequencing and shotgun metagenomics to characterize microbial diversity in soil. However, challenges persist in the study of microbial diversity, including the recalcitrance of the majority of microorganisms to laboratory cultivation and limited sequence assembly from highly complex samples. The uncultivated majority thus remains a reservoir of untapped genetic diversity. To address some of the challenges associated with bulk metagenomics as well as low throughput of single-cell genomics, we applied flow cytometry-enabled mini-metagenomics to capture expanded microbial diversity from forest soil and compare it to soil bulk metagenomics. Our resulting data from this pooled-cell sorting approach combined with bulk metagenomics revealed increased phylogenetic diversity through novel soil taxa and rare biosphere members. In-depth analysis of genomes within the highly represented Bacteroidetes phylum provided insights into conserved and clade-specific patterns of carbon metabolism.

3.
J Cell Biol ; 125(1): 67-86, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8138576

RESUMEN

Classically, the polymeric immunoglobulin receptor and its ligand, IgA, are thought to be sorted from basolateral early endosomes into transcytotic vesicles that directly fuse with the apical plasma membrane. In contrast, we have found that in MDCK cells IgA is delivered from basolateral endosomes to apical endosomes and only then to the apical cell surface. When internalized from the basolateral surface of MDCK cells IgA is found to accumulate under the apical plasma membrane in a compartment that is accessible to two apically added membrane markers: anti-secretory component Fab fragments, and avidin internalized from the biotinylated apical pole of the cell. This accumulation occurs in the presence of apical trypsin, which prevents internalization of the ligand from the apical cell surface. Using a modification of the diaminobenzidine density-shift assay, we estimate that approximately 80% of basolaterally internalized IgA resides in the apical endosomal compartment. In addition, approximately 50% of basolaterally internalized transferrin, a basolateral recycling protein, has access to this apical endosomal compartment and is efficiently recycled back to the basolateral surface. Microtubules are required for the organization of the apical endosomal compartment and it is dispersed in nocodazole-treated cells. Moreover, this compartment is largely inaccessible to fluid-phase markers added to either pole of the cell, and therefore seems analogous to the recycling endosome described in nonpolarized cells. We propose a model in which transcytosis is not a specialized pathway that uses unique transcytotic vesicles, but rather combines portions of pathways used by non-transcytosing molecules.


Asunto(s)
Endocitosis , Inmunoglobulina A/metabolismo , Componente Secretorio/metabolismo , Animales , Transporte Biológico , Compartimento Celular , Línea Celular , Polaridad Celular , Perros , Exocitosis , Técnica del Anticuerpo Fluorescente , Microtúbulos/fisiología , Receptores Inmunológicos , Transferrina/metabolismo , Tubulina (Proteína)/fisiología
4.
Science ; 232(4754): 1121-3, 1986 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-3704638

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy was used to monitor, on a beat-to-beat basis, the concentration of creatine phosphate and adenosine triphosphate during alterations in the work output of canine hearts in vivo. Over a wide range of rate-pressure products (5,000 to 25,000 mmHg/min), the relative amounts of creatine phosphate and adenosine triphosphate within the heart remained constant. The relative concentration of free adenosine diphosphate was calculated under the reasonable assumption that the creatine kinase-catalyzed reaction is near equilibrium in this tissue. The free concentration of adenosine diphosphate also did not change over this range of rate-pressure products. The data demonstrate that the concentration of these compounds is highly regulated in vivo and suggest that factors other than their concentration may be involved in the modulation of steady-state myocardial work output with oxygen consumption.


Asunto(s)
Adenosina Trifosfato/análisis , Corazón/fisiología , Miocardio/análisis , Fosfocreatina/análisis , Adenosina Difosfato/análisis , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Frecuencia Cardíaca , Espectroscopía de Resonancia Magnética , Mitocondrias Cardíacas/metabolismo , Miocardio/metabolismo , Consumo de Oxígeno , Fosfocreatina/metabolismo
5.
J Perinatol ; 26(7): 414-22, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16724122

RESUMEN

OBJECTIVE: To evaluate repeat surfactant therapy for the treatment of respiratory failure associated with postsurfactant slump in extremely low birth weight infants (ELBW) by characterizing the population of premature infants who develop postsurfactant slump and measuring their response to a secondary course of surfactant therapy. STUDY DESIGN: A retrospective analysis of a cohort of all patients admitted over a 3-year period with birth weights <1000 g (ELBW infants). Information was collected by chart review and the patients were categorized into three distinct groups for analysis. Initial surfactant only, patients who received surfactant replacement therapy only for respiratory distress syndrome (RDS); repeat surfactant, patients who received both initial surfactant replacement for RDS and repeat surfactant therapy for postsurfactant slump (defined as respiratory failure after 6 days of age), and no surfactant, patients in whom no surfactant was ever administered. A respiratory severity score (RSS) was used to measure the severity of lung disease and response to surfactant therapy. RESULTS: Over 3 years, there were 165 ELBW infants who could develop postsurfactant slump and be eligible for repeat surfactant therapy. There were 39 infants who never received any surfactant therapy estimated gestational age (EGA) 27.7 +/- 1.7, birth weight 856 +/- 109 g) either at birth or after 6 days of life. There were 126 patients treated for RDS with initial surfactant replacement therapy (EGA 25.6 +/- 1.9 weeks, birth weight 713 +/- 179 g). Out of these RDS patients, 101 improved with an initial course of surfactant therapy (EGA 26 +/- 1.8, birth weight 751 +/- 143 g), but 25 (20% of the patients with RDS) developed postsurfactant slump and received a repeat course of surfactant therapy (EGA 24.7 +/- 1.2, birth weight 647 +/- 120 g). The repeat surfactant group (postsurfactant slump) was significantly more premature and had significantly lower birth weights compared to both the initial surfactant only group and the no surfactant ever group. Logistic regression analysis revealed that lack of antenatal steroids, earlier gestational age, and the receiving of 2 or more doses of surfactant to treat the initial RDS were significantly associated with receiving repeat surfactant therapy for postsurfactant slump. Of the 25 patients treated with a repeat course of surfactant therapy more than 70% of patients (n = 18) had an improvement in their lung disease with a 15% reduction in their RSS. This improvement was significant at all time points evaluated (12, 24, and 48 h). CONCLUSION: We found that a repeat course of surfactant therapy, after day of life 6, led to a significant improvement in hypoxemic respiratory failure in premature infants with postsurfactant slump. Infants who received repeat surfactant therapy were born at a significantly earlier gestational age, had significantly smaller birth weight and had significantly worse lung disease. They were significantly less likely to have received antenatal steroids and were significantly more likely to have received multiple doses of surfactant to treat their initial RDS. A repeat course of surfactant therapy for patients with postsurfactant slump appeared beneficial in the short-term. These initial findings would support performing randomized control trials of repeat surfactant therapy for postsurfactant slump.


Asunto(s)
Recién Nacido de muy Bajo Peso , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Humanos , Recién Nacido , Modelos Logísticos , Surfactantes Pulmonares/administración & dosificación , Respiración Artificial , Síndrome de Dificultad Respiratoria del Recién Nacido/fisiopatología , Estudios Retrospectivos , Resultado del Tratamiento
6.
Genetics ; 147(2): 609-21, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9335598

RESUMEN

Two species of crickets, Gryllus veletis and G. pennsylvanicus, share six electrophoretic mobility classes for the enzyme phosphoglucose isomerase (PGI), despite evidence from other genetic markers that the two species are not closely related within eastern North American field crickets. Moreover, the frequencies of the two most common PGI electrophoretic classes (PGI-100 and PGI-65) covary in sympatric populations of these species in the eastern United States, suggesting that PGI may be subject to trans-specific balancing selection. To determine the molecular basis of the electrophoretic variation, we characterized the DNA sequence of the Pgi gene from 29 crickets (15 G. veletis and 14 G. pennsylvanicus). Amino acid substitutions that distinguish the electrophoretic classes are not the same in the two species, and there is no evidence that specific replacement substitutions represent trans-specific polymorphism. In particular, the amino acids that diagnose the PGI-65 allele relative to the PGI-100 allele differ both between G. veletis and G. pennsylvanicus and within G. pennsylvanicus. The heterogeneity among electrophoretic classes that covary in sympatric populations coupled with analysis of patterns of nucleotide variation suggest that Pgi is not evolving neutrally. Instead, the data are consistent with balancing selection operating on an emergent property of the PGI protein.


Asunto(s)
Glucosa-6-Fosfato Isomerasa/genética , Gryllidae/enzimología , Animales , ADN Complementario , Electroforesis en Acetato de Celulosa , Gryllidae/genética , Polimorfismo Genético , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
7.
Arch Intern Med ; 158(11): 1197-207, 1998 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-9625399

RESUMEN

OBJECTIVE: To determine whether blood pressure is reduced for at least 6 months with an intervention to lower alcohol intake in moderate to heavy drinkers with above optimal to slightly elevated diastolic blood pressure, and whether reduction of alcohol intake can be maintained for 2 years. DESIGN: A randomized controlled trial. METHODS: Six hundred forty-one outpatient veterans with an average intake of 3 or more alcoholic drinks per day in the 6 months before entry into the study and with diastolic blood pressure 80 to 99 mm Hg were randomly assigned to a cognitive-behavioral alcohol reduction intervention program or a control observation group for 15 to 24 months. The goal of the intervention was the lower of 2 or fewer drinks daily or a 50% reduction in intake. A subgroup with hypertension was defined as having a diastolic blood pressure of 90 to 99 mm Hg, or 80 to 99 mm Hg if recently taking medication for hypertension. RESULTS: Reduction in average weekly self-reported alcohol intake was significantly greater (P<.001) at every assessment from 3 to 24 months in the intervention group vs the control group: levels declined from 432 g/wk at baseline by 202 g/wk in the intervention group and from 445 g/wk by 78 g/wk in the control group in the first 6 months, with similar reductions after 24 months. The intervention group had a 1.2/0.7-mm Hg greater reduction in blood pressure than the control group (for each, P = .17 and P = .18) for the 6-month primary end point; for the hypertensive stratum the difference was 0.9/0.7 mm Hg (for each, P = .58 and P = .44). CONCLUSIONS: The 1.3 drinks per day average difference between changes in self-reported alcohol intake observed in this trial produced only small nonsignificant effects on blood pressure. The results from the Prevention and Treatment of Hypertension Study (PATHS) do not provide strong support for reducing alcohol consumption in nondependent moderate drinkers as a sole method for the prevention or treatment of hypertension.


Asunto(s)
Consumo de Bebidas Alcohólicas , Hipertensión/terapia , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Etanol/farmacología , Femenino , Humanos , Hipertensión/prevención & control , Masculino , Persona de Mediana Edad , Factores de Tiempo
8.
Clin Pharmacol Ther ; 48(6): 665-75, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2249378

RESUMEN

The purpose of this multicenter investigation was to determine the efficacy and safety of the alpha/beta-blocker labetalol versus the beta 1-selective beta-blocker atenolol in white and black patients with essential hypertension. Equal numbers of black and white patients were enlisted to form four treatment groups (white patients taking either labetalol or atenolol and black patients taking either labetalol or atenolol). Two hundred ninety-two patients (152 white and 140 black patients) with essential hypertension characterized by a standing diastolic blood pressure of 105 to 119 mm Hg (inclusive) were recruited for this trial. Patients were randomized to either labetalol (dosage titrated from 200 to 1600 mg/day) or atenolol (dosage titrated from 50 to 100 mg/day). The therapeutic goal was achievement of a standing diastolic blood pressure of 90 mm Hg or less or a fall of 15 mm Hg in diastolic pressure from baseline value at the end of the placebo run in period. At the end of the study there were no significant differences in blood pressure or heart rate changes in the supine position between the labetalol and atenolol groups. In contrast, labetalol produced greater reduction in both the standing systolic and diastolic blood pressure (-12/-13 mm Hg, respectively) compared with atenolol (-7/-9 mm Hg; p less than 0.05; p less than 0.005, respectively). The greatest decrease in blood pressure was observed in white patients receiving labetalol. In black patients the decrease in blood pressure was greater in those treated with labetalol compared with atenolol, particularly with respect to the systolic blood pressure. We conclude that the alpha 1-blocking property of labetalol provides an additional lowering of the blood pressure over that seen with beta 1-blockade alone, especially in the standing position, and this enhanced efficacy is not confined to one radical group.


Asunto(s)
Atenolol/uso terapéutico , Hipertensión/tratamiento farmacológico , Labetalol/uso terapéutico , Atenolol/efectos adversos , Población Negra , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/fisiopatología , Labetalol/efectos adversos , Estudios Prospectivos , Población Blanca
9.
FEBS Lett ; 221(2): 270-6, 1987 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-3622766

RESUMEN

The phosphate metabolites, adenosine diphosphate (ADP), inorganic phosphate (Pi), and adenosine triphosphate (ATP), are potentially important regulators of mitochondrial respiration in vivo. However, previous studies on the heart in vivo and in vitro have not consistently demonstrated an appropriate correlation between the concentration of these phosphate metabolites and moderate changes in work and respiration. Recently, mitochondrial NAD(P)H levels have been proposed as a potential regulator of cardiac respiration during alterations in work output. In order to understand better the mechanism of respiratory control under these conditions, we investigated the relationship between the phosphate metabolites, the NAD(P)H levels, and oxygen consumption (Q02) in the isovolumic perfused rat heart during alterations in work output with pacing. ATP, creatine phosphate (CrP), Pi and intracellular pH were measured using 31P NMR. Mitochondrial NAD(P)H levels were monitored using spectrofluorometric techniques. Utilizing glucose as the sole substrate, an increase in paced heart rate led to an increase in Q02 from 1.73 +/- 0.09 to 2.29 +/- 0.12 mmol Q2/h per g dry wt. No significant changes in the levels of Pi, PCr, ATP, or the calculated ADP levels were detected. Under identical conditions, an increase in heart rate was associated with a 23 + 3% increase in NAD(P)H fluorescence. Thus, under the conditions of these studies, an increase in Q02 was not associated with an increase in ADP or Pi. In contrast, increases in Q02 were associated with an increase in NAD(P)H. These data are consistent with the notion that increases in the mitochondrial NADH redox state regulate steady-state levels of respiration when myocardial work is increased.


Asunto(s)
Miocardio/metabolismo , NAD/análisis , Consumo de Oxígeno , Fosfatos/metabolismo , Adenosina Difosfato/análisis , Adenosina Trifosfato/análisis , Animales , Fluorescencia , Glucosa/farmacología , Espectroscopía de Resonancia Magnética , Masculino , Perfusión , Fosfocreatina/análisis , Ratas , Ratas Endogámicas
10.
Evolution ; 55(11): 2287-302, 2001 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-11794788

RESUMEN

The plethodontid salamander Desmognathus orestes, a member of the D. ochrophaeus species complex, is distributed in southwestern Virginia, eastern Tennessee, and western North Carolina. Previous allozyme analyses indicate that D. orestes consists of two distinct groups of populations (D. orestes 'B' and D. orestes 'C') with extensive intergradation and probable gene flow between these two groups. Spatially varying allele frequencies can reflect historical associations, current gene flow, or a combination of population-level processes. To differentiate among these processes, we use multiple markers to further characterize divergence among populations of D. orestes and assess the degree of intergradation between D. orestes 'B' and D. orestes 'C', specifically investigating variation in allozymes, mitochondrial DNA (mtDNA), and reproductive behavior among populations. On a broad scale, the mtDNA genealogies reconstruct haplotype clades that correspond to the species identified from previous allozyme analyses. However, at a finer geographic scale, the distributions of the allozyme and mtDNA markers for D. orestes 'B' and D. orestes 'C' are discordant. MtDNA haplotypes corresponding to D. orestes 'B' are more broadly distributed across western North Carolina than predicted by allozyme data, and the region of intergradation with D. orestes 'C' indicates asymmetric gene flow of these markers. Asymmetric mating may contribute to observed discordance in nuclear versus cytoplasmic markers. Results support describing D. orestes as a single species and emphasize the importance of using multiple markers to examine fine-scale patterns and elucidate evolutionary processes affecting gene flow when making species-level taxonomic decisions.


Asunto(s)
ADN Mitocondrial/análisis , Isoenzimas/genética , Urodelos/genética , Animales , Femenino , Frecuencia de los Genes , Variación Genética , Haplotipos , Funciones de Verosimilitud , Masculino , Filogenia , Conducta Sexual Animal , Urodelos/clasificación , Urodelos/fisiología
11.
Am J Med ; 81(4): 635-40, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3766593

RESUMEN

Systemic amyloidosis has recently emerged as a major cause of nephropathy among heroin abusers in New York City. Although focal glomerulosclerosis is typically seen in intravenous drug abusers who present with the nephrotic syndrome, those who escape this complication are at risk for the later development of amyloidosis related to their use of the subcutaneous route. Twenty such addicts identified between 1981 and 1984 are described. Patients typically present with chronic suppurative skin infections, edema, the nephrotic syndrome, benign urinary sediment, and normal-sized or enlarged kidneys. Tubular dysfunction, particularly renal tubular acidosis and diabetes insipidus, is frequent. Progression of renal insufficiency is characteristically rapid. Prolonged survival of heroin abusers and exhaustion of intravenous access requiring recourse to the subcutaneous route underlie the occurrence of amyloidosis in the addict population. Chronic suppurative skin infection consequent to repeated subcutaneous injection appears to be the underlying cause.


Asunto(s)
Amiloidosis/etiología , Heroína , Enfermedades Renales/etiología , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Amiloidosis/complicaciones , Amiloidosis/fisiopatología , Femenino , Humanos , Inyecciones Subcutáneas , Enfermedades Renales/complicaciones , Enfermedades Renales/patología , Masculino , Persona de Mediana Edad
12.
Semin Nephrol ; 19(2): 140-7, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10192246

RESUMEN

Nephrologists are frequently responsible for the primary care of their female patients. As such, they must be aware of medical issues that are unique to women. Although many of the medical considerations are similar to those in women without renal disease, there are a number of special considerations unique to end-stage renal disease (ESRD) patients. Women comprise a smaller proportion of the dialysis population and have better survival rates than men do. The improved survival is less marked than seen in the general population and may be function of differential susceptibility to disease processes, socio-cultural factors, or gender differences in acceptance or transplantation rates. A variety of factors are important in choosing dialysis modality including lifestyle issues and previous abdominal surgery. Women with ESRD are at high risk of both sexual and gonadal dysfunction, for which the latter may be treated with replacement hormones. Pregnancy is rare and requires an increase in the dose of dialysis and the care of a team of experienced physicians. Finally, awareness and implementation of routine health maintenance recommendations is essential in the care of female dialysis patients.


Asunto(s)
Fallo Renal Crónico , Diálisis Peritoneal , Diálisis Renal , Femenino , Humanos , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/terapia , Masculino , Diálisis Peritoneal/estadística & datos numéricos , Embarazo , Diálisis Renal/estadística & datos numéricos , Factores Sexuales , Estados Unidos/epidemiología
13.
J Am Geriatr Soc ; 34(10): 693-6, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3531295

RESUMEN

The safety and efficacy of captopril in geriatric patients with mild to moderate hypertension was examined in an eight-week multicenter study of 99 patients. Following a placebo period, patients were treated with captopril 25 mg twice daily. Patients who were uncontrolled after two weeks of active therapy were randomized to either captopril 25 mg plus hydrochlorothiazide 15 mg or captopril 50 mg twice daily. The average decrease in blood pressure at study completion was--16.9/11.9 mmHg. At the conclusion of the trial, 75.8% of patients responded to therapy. Captopril was well tolerated and believed to be a good therapeutic alternative for treating hypertension in the elderly population.


Asunto(s)
Captopril/uso terapéutico , Hipertensión/tratamiento farmacológico , Negro o Afroamericano , Factores de Edad , Anciano , Presión Sanguínea/efectos de los fármacos , Captopril/efectos adversos , Captopril/farmacología , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Humanos , Hidroclorotiazida/efectos adversos , Hidroclorotiazida/uso terapéutico , Masculino , Persona de Mediana Edad , Distribución Aleatoria
14.
Am J Hypertens ; 1(4 Pt 2): 372S-377S, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3056447

RESUMEN

Treating older hypertensive patients presents special challenges. The physiological effects of aging result in hemodynamic and pharmacokinetic changes. Geriatric patients are more likely to have concomitant diseases than younger patients. Treatment regimens should be individualized; monotherapy should be the goal. While most antihypertensive agents can be used, each class of drugs has advantages and disadvantages. Diuretics are both effective and inexpensive but their metabolic side effects (especially hypokalemia) may be quite serious in the geriatric population. Sympatholytics, beta-blockers, alpha-blockers, and direct vasodilators may not be tolerated. The angiotension-converting enzyme inhibitors, captopril and enalapril, are good choices because they have favorable hemodynamics, renin and nonrenin-dependent mechanisms of action and are associated with minimal biochemical alterations. In a recent multicenter study, captopril (25 mg twice daily) was given to 99 geriatric patients with seated diastolic blood pressure (BP) of 92-110 mm Hg. Patients whose blood pressures were not controlled after two weeks of therapy were randomized to either Capozide (captopril, 25 mg with 15 mg hydrochlorothiazide) or captopril, 50 mg twice daily. The average decrease in BP was 16.9/11.9 mm Hg; 75.8% of patients responded to treatment. Black and white patients had equal responses. Only five patients withdrew from the study due to adverse reactions, none of which was serious. Geriatric hypertensives should be treated. Because captopril and Capozide are well-tolerated, effective medications in elderly patients with mild, moderate, or severe hypertension, they should be considered as initial therapy for geriatric hypertension.


Asunto(s)
Anciano , Antihipertensivos/uso terapéutico , Hipertensión/fisiopatología , Humanos , Hipertensión/tratamiento farmacológico , Persona de Mediana Edad
15.
Am J Hypertens ; 1(3 Pt 3): 224S-226S, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3046629

RESUMEN

Twenty-four black men with mild to moderate essential hypertension were enrolled in an open-label trial comparing the efficacy of two doses of Capozide (captopril and hydrochlorothiazide). All antihypertensive drugs were discontinued and patients then received placebo for 2 weeks. Twenty-two patients, mean age 59.1 +/- 14.3 years, with sitting diastolic blood pressure (BP) 92 to 110 mm Hg, entered the 6-week active-drug phase. Eleven patients (Group A) were randomized to Capozide 25/15 and 11 (Group B) to Capozide 50/15. Baseline mean BPs were 151.0/100.7 mm Hg in Group A and 153.1/100.7 mm Hg in Group B. At week 6, mean BPs were 128.7/84.4 mm Hg in Group A and 126.8/82.7 mm Hg in Group B. Uric acid, blood urea nitrogen and creatinine levels rose slightly in both groups. There were no adverse events. Eighteen patients had normal BPs at study completion. Twice-daily Capozide treatment is effective and well tolerated in blacks; patients responded equally well to both doses.


Asunto(s)
Población Negra , Captopril/uso terapéutico , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Presión Sanguínea/efectos de los fármacos , Nitrógeno de la Urea Sanguínea , Ensayos Clínicos como Asunto , Creatinina/sangre , Combinación de Medicamentos/uso terapéutico , Femenino , Humanos , Hipertensión/fisiopatología , Persona de Mediana Edad , Ácido Úrico/sangre
16.
Urology ; 17(3): 260-4, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7210378

RESUMEN

Eight cases of acquired cystic disease of the kidney (ACDK) associated with chronic renal failure and hemodialysis are described. No patient had a family history or clinical evidence of congenital adult polycystic kidney disease (CAPKD). Glomerulonephritis was the cause of renal failure in 6, and pyelonephritis in 2. Massive renal and perirenal hemorrhage necessitated 3 nephrectomies in 2 patients. Single kidney weights did not exceed 280 Gm., a major feature in the distinction of ACDK from CAPKD. Morphologically, in addition to the usual stigmata of end-stage kidneys, 40 to 80 per cent of the renal parenchyma was replaced by small cysts. Continuity of cysts with tubules was established by nephron dissection.


Asunto(s)
Enfermedades Renales Quísticas/etiología , Diálisis Renal/efectos adversos , Femenino , Hemorragia/etiología , Humanos , Enfermedades Renales Quísticas/patología , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Tamaño de los Órganos
18.
Neurogastroenterol Motil ; 22(8): 893-900, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20465594

RESUMEN

BACKGROUND: This study assessed the association between social support and the severity of irritable bowel syndrome (IBS) symptoms in a sample of severely affected IBS patients recruited to an NIH-funded clinical trial. In addition, we examined if the effects of social support on IBS pain are mediated through the effects on stress. METHODS: Subjects were 105 Rome II diagnosed IBS patients (F = 85%) who completed seven questionnaires which were collected as part of a pretreatment baseline assessment. KEY RESULTS: Partial correlations were conducted to clarify the relationships between social support and clinically relevant variables with baseline levels of psychopathology, holding constant number of comorbid medical diseases, age, gender, marital status, ethnicity, and education. Analyses indicated that social support was inversely related to IBS symptom severity. Social support was positively related with less severe pain. A similar pattern of data was found for perceived stress but not quality of life impairment. Regression analyses examined if the effects of social support on pain are mediated by stress. The effects of social support on bodily pain were mediated by stress such that the greater the social support the less stress and the less pain. This effect did not hold for symptom severity, quality of life, or psychological distress. CONCLUSIONS & INFERENCES: This study links the perceived adequacy of social support to the global severity of symptoms of IBS and its cardinal symptom (pain). It also suggests that the mechanism by which social support alleviates pain is through a reduction in stress levels.


Asunto(s)
Síndrome del Colon Irritable/fisiopatología , Síndrome del Colon Irritable/psicología , Dolor/psicología , Índice de Severidad de la Enfermedad , Apoyo Social , Estrés Psicológico/psicología , Adulto , Anciano , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida/psicología , Estrés Psicológico/fisiopatología , Encuestas y Cuestionarios
19.
Neurogastroenterol Motil ; 22(5): 527-33, e117, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20122128

RESUMEN

BACKGROUND: The wireless motility capsule (WMC) measures intraluminal pH and pressure, and records transit time and contractile activity throughout the gastrointestinal tract. Our hypothesis is that WMC can differentiate antroduodenal pressure profiles between healthy people and patients with upper gut motility dysfunctions. This study aims to analyze differences in the phasic pressure profiles of the stomach and small intestine in healthy and gastroparetic subjects. METHODS: Data from 71 healthy and 42 gastroparetic subjects were analyzed. The number of contractions (Ct), area under the pressure curve and motility index (MI = Ln (Ct *sum amplitudes +1)) were analyzed for 60 min before gastric emptying of the capsule (GET), (gastric window) and after GET (small bowel window) and results between groups were compared with the Wilcoxon rank sum test. KEY RESULTS: Significant differences were observed between healthy and gastroparetic subjects for Ct and MI (P < 0.05). Median values of the motility parameters in gastric window were Ct = 72, MI = 11.83 for healthy and Ct = 47, MI = 11.12 for gastroparetics. In the small bowel, median values were Ct = 144.5, MI = 12.78 for healthy and Ct = 93, MI = 12.12 for gastroparetics. Diabetic subjects with gastroparesis showed significantly lower Ct and MI compared with healthy subjects in both gastric and small bowel windows while idiopathic gastroparetic subjects did not show significant differences. CONCLUSIONS & INFERENCES: The WMC is able to differentiate between healthy and gastroparetic subjects based on gastric and small bowel motility profiles.


Asunto(s)
Duodeno/fisiopatología , Motilidad Gastrointestinal/fisiología , Gastroparesia/fisiopatología , Antro Pilórico/fisiopatología , Adulto , Factores de Edad , Anciano , Área Bajo la Curva , Monitorización del pH Esofágico , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Selección de Paciente , Factores Sexuales
20.
Aliment Pharmacol Ther ; 31(2): 313-22, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19814743

RESUMEN

BACKGROUND: Wireless pH and pressure motility capsule (wireless motility capsule) technology provides a method to assess regional gastrointestinal transit times. AIMS: To analyse data from a multi-centre study of gastroparetic patients and healthy controls and to compare regional transit times measured by wireless motility capsule in healthy controls and gastroparetics (GP). METHODS: A total of 66 healthy controls and 34 patients with GP (15 diabetic and 19 idiopathic) swallowed wireless motility capsule together with standardized meal (255 kcal). Gastric emptying time (GET), small bowel transit time (SBTT), colon transit time (CTT) and whole gut transit time (WGTT) were calculated using the wireless motility capsule. RESULTS: Gastric emptying time, CTT and WGTT but not SBTT were significantly longer in GP than in controls. Eighteen percent of gastroparetic patients had delayed WGTT. Both diabetic and idiopathic aetiologies of gastroparetics had significantly slower WGTT (P < 0.0001) in addition to significantly slower GET than healthy controls. Diabetic gastroparetics additionally had significantly slower CTT than healthy controls (P = 0.0054). CONCLUSIONS: In addition to assessing gastric emptying, regional transit times can be measured using wireless motility capsule. The prolongation of CTT in gastroparetic patients indicates that dysmotility beyond the stomach in GP is present, and it could be contributing to symptom presentation.


Asunto(s)
Endoscopía Capsular/métodos , Colon/fisiología , Motilidad Gastrointestinal/fisiología , Tránsito Gastrointestinal/fisiología , Gastroparesia/fisiopatología , Adolescente , Adulto , Anciano , Femenino , Motilidad Gastrointestinal/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos
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