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1.
Pancreatology ; 22(7): 1028-1034, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35948507

RESUMEN

BACKGROUND AND AIMS: Pancreatic resection is associated with pancreatic exocrine insufficiency (PEI) leading to nutritional consequences. The Pancreatic Nutrition Clinic was established to diagnose and manage PEI through standardised nutritional assessment. In this prospective observational study, we aimed to define the rate of PEI, diabetes mellitus and nutritional abnormalities in patients who underwent pancreatic resection. METHODS: All Pancreatic Nutrition Clinic patients were included for analysis. Clinical data were prospectively obtained at initial assessment. Biochemical data included micronutrient levels, faecal elastase-1 and haemoglobin A1c. Bone mineral density and nutritional assessment were undertaken. RESULTS: Ninety-eight patients were included. Fifty-nine per cent (58/98) had undergone a pancreatoduodenectomy. Ninety-three patients had a faecal elastase-1 result, 65% (60/93) of which had a faecal elastase-1 less than 200 µg/g of faeces. Seventy-five patients (76%) of the total population required PERT, and thirty-nine (40%) were classified as malnourished using the patient-generated subjective global assessment tool. Seventy-two per cent (70/97) had a biochemical deficiency of one or more micronutrients. Thirty-eight people (39%) had diabetes mellitus. Of the seventy-eight patients with a bone mineral density scan available for analysis, 29% (23/78) had osteoporosis and 49% (38/78) osteopenia. CONCLUSIONS: Pancreatic exocrine insufficiency, micronutrient deficiency, bone disease, diabetes mellitus and malnutrition are highly prevalent in patients who have undergone pancreatic resection.


Asunto(s)
Diabetes Mellitus , Insuficiencia Pancreática Exocrina , Desnutrición , Enfermedades Metabólicas , Humanos , Insuficiencia Pancreática Exocrina/diagnóstico , Elastasa Pancreática/análisis , Micronutrientes
2.
J Stat Educ ; 28(3): 295-303, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33776396

RESUMEN

Biostatisticians with advanced degrees are highly sought after. Employment opportunities in the fields of mathematics and statistics are expected to increase dramatically by 2028. Underrepresentation of minorities in biostatistics has been a persistent problem, yielding a demographic landscape that differs substantially from the general US population. In some instances, students may have the appropriate quantitative skills, but are unaware of biostatistics and in other instances, students may not yet have the appropriate quantitative background, but are intellectually capable and willing to shore up those skills once they learn about biostatistics as a viable, exciting career option. Therefore, in order to ensure robust scientific advancement, there must be a concerted effort to increase the pipeline of intellectually talented persons available with exposure to the appropriate quantitative skills who are interested in careers in biostatistics. The overarching goal of this paper is to discuss the development, implementation, and impact of a federally funded pipeline initiative aimed at increasing the number of underrepresented minorities successful in graduate training and professional careers in biostatistics as well as establishing effective mentoring and networking relationships. Our findings provide a roadmap for the development of sustainable initiatives to promote diversity in biostatistics and STEM fields more broadly.

3.
Ann Oncol ; 25(10): 2047-2052, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25091317

RESUMEN

BACKGROUND: Although advanced cutaneous squamous cell carcinoma (CSCC) is quite common, there are few prospective trials regarding its optimal management. This study evaluated the efficacy and safety of single-agent panitumumab in the treatment of patients with CSCC not suitable for local therapy. PATIENTS AND METHODS: Sixteen patients received single-agent panitumumab at a dose of 6 mg/kg repeated every 2 weeks for a minimum of three cycles and continued until progression, a maximum of nine cycles or dose-limiting toxicity. The primary end point was the best overall response rate (ORR) as assessed by Response Evaluation Criteria in Solid Tumours (RECIST version 1.1) criteria. Secondary end points included evaluation of safety, toxicity and progression-free survival (PFS). RESULTS: Between May 2010 and May 2012, 16 patients were recruited. Fourteen patients were male and the median age was 68 years. Fifteen patients had locoregionally advanced or recurrent disease with 14 patients receiving previous radiotherapy and 7 receiving previous cytotoxic chemotherapy. The best ORR [partial (PR) or complete response (CR)] was 31% (3/16 PR, 2/16 CR) with a further 6 of 16 patients achieving SD. The median PFS and overall survival were 8 and 11 months respectively. Grade 3 or 4 events were observed in five patients (four being skin toxicity) with one patient ceasing due to skin toxicity. With a median follow-up of 24 months, 10 patients died due to progressive disease, 6 are alive, one patient with no evidence of disease at the time of analysis. CONCLUSIONS: Single-agent panitumumab is safe and effective in the management of patients with advanced CSCC even in a previously extensively pre-treated cohort.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Panitumumab , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología
4.
J Eur Acad Dermatol Venereol ; 27(3): 267-72, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22632057

RESUMEN

OBJECTIVE: To compare mycological and complete cures of terbinafine continuous and intermittent regimens in the treatment of toenail onychomycosis. METHODS: The PubMed database was searched using the terms "terbinafine", "onychomycosis", "continuous" and "pulse(d)" or "intermittent". The inclusion criteria were head-to-head comparison of terbinafine pulse and continuous regimens for dermatophyte toenail infections. Risk ratios were calculated for intention-to-treat and evaluable patient analyses, when possible. Pooled estimates for total and subgroup analyses were calculated using a random effect model, Mantel-Haenszel method and their probabilities were calculated with z-statistics. RESULTS: Nine studies from eight publications were included. Two continuous regimens and four intermittent regimens were investigated. A pooled risk ratio of 0.87 was obtained for intention-to-treat (95% CI: 0.79-0.96, P = 0.004, n = 6) and evaluable patient (95% CI: 0.80-0.96, P = 0.003, n = 8) analyses of mycological cure, favouring continuous terbinafine. For complete cure, pooled risk ratios of 0.97 (95% CI: 0.77-1.23, P = 0.82, n = 7) for intention-to-treat and 0.93 (95% CI: 0.76-1.13, P = 0.44, n = 9) for evaluable patient analyses showed equality of the two regimens. The pulse regimen that demonstrated consistently comparable results to the continuous terbinafine regimen was two pulses of terbinafine 250 mg/day for 4 weeks on/4 weeks off. CONCLUSIONS: Meta-analysis of published studies of toenail onychomycosis showed that a continuous terbinafine regimen is generally significantly superior to a pulsed terbinafine regimen for mycological cure. In contrast, some pulse terbinafine regimens were as effective as continuous terbinafine regimens for complete cure.


Asunto(s)
Antifúngicos/uso terapéutico , Enfermedades de la Uña/tratamiento farmacológico , Naftalenos/uso terapéutico , Humanos , Onicomicosis/tratamiento farmacológico , Terbinafina , Resultado del Tratamiento
5.
Skin Therapy Lett ; 17(9): 4-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23032936

RESUMEN

Device-based therapies are promising alternatives for the treatment of onychomycosis because they can mitigate some of the negative factors associated with treatment failure. There are four categories of device-based treatments: laser devices, photodynamic therapy, iontophoresis, and ultrasound. These therapeutic modalities are noninvasive procedures that are carried out by medical professionals, reduce the need for long-term patient adherence, and avoid adverse reactions associated with conventional systemic antifungal therapies.


Asunto(s)
Iontoforesis/métodos , Terapia por Láser/métodos , Onicomicosis/terapia , Fotoquimioterapia/métodos , Ultrasonografía/métodos , Humanos , Onicomicosis/diagnóstico por imagen
6.
Nat Cell Biol ; 1(2): 119-24, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10559884

RESUMEN

Several SH3-domain-containing proteins have been implicated in endocytosis by virtue of their interactions with dynamin; however, their functions remain undefined. Here we report the efficient reconstitution of ATP-, GTP-, cytosol- and dynamin-dependent formation of clathrin-coated vesicles in permeabilized 3T3-L1 cells. The SH3 domains of intersectin, endophilin I, syndapin I and amphiphysin II inhibit coated-vesicle formation in vitro through interactions with membrane-associated proteins. Most of the SH3 domains tested selectively inhibit late events involving membrane fission, but the SH3A domain of intersectin uniquely inhibits intermediate events leading to the formation of constricted coated pits. These results suggest that interactions between SH3 domains and their partners function sequentially in endocytic coated-vesicle formation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular , Proteínas Portadoras/metabolismo , Clatrina/metabolismo , Vesículas Cubiertas/fisiología , Endocitosis/fisiología , GTP Fosfohidrolasas/metabolismo , Dominios Homologos src , Células 3T3 , Adenosina Trifosfato/metabolismo , Adipocitos/citología , Adipocitos/fisiología , Animales , Proteínas Portadoras/química , Vesículas Cubiertas/ultraestructura , Proteínas del Citoesqueleto , Dinaminas , Glutatión Transferasa/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Ratones , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Células Tumorales Cultivadas
7.
Sci Rep ; 11(1): 16666, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404875

RESUMEN

Oxygen delivery to the retinal pigment epithelium and the outer retina is essential for metabolism, function, and survival of photoreceptors. Chronically reduced oxygen supply leads to retinal pathologies in patients and causes age-dependent retinal degeneration in mice. Hypoxia can result from decreased levels of inspired oxygen (normobaric hypoxia) or reduced barometric pressure (hypobaric hypoxia). Since the response of retinal cells to chronic normobaric or hypobaric hypoxia is mostly unknown, we examined the effect of six hypoxic conditions on the retinal transcriptome and photoreceptor morphology. Mice were exposed to short- and long-term normobaric hypoxia at 400 m or hypobaric hypoxia at 3450 m above sea level. Longitudinal studies over 11 weeks in normobaric hypoxia revealed four classes of genes that adapted differentially to the hypoxic condition. Seventeen genes were specifically regulated in hypobaric hypoxia and may affect the structural integrity of the retina, resulting in the shortening of photoreceptor segment length detected in various hypoxic groups. This study shows that retinal cells have the capacity to adapt to long-term hypoxia and that consequences of hypobaric hypoxia differ from those of normobaric hypoxia. Our datasets can be used as references to validate and compare retinal disease models associated with hypoxia.


Asunto(s)
Hipoxia/genética , Retina/patología , Transcriptoma , Animales , Femenino , Humanos , Hipoxia/etiología , Hipoxia/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Retina/metabolismo
8.
J Cell Biol ; 38(1): 184-92, 1968 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-5691972

RESUMEN

The distribution of infused tritiated norepinephrine (NE-(3)H) in small mesenteric arteries and intestinal arterioles in rats was investigated with electron microscopic radioautography. Silver grains, indicating the presence of the tritium label on the sections, were found lying mainly over axon bundles, but some were present over collagen and smooth muscle cells. Axons with the highest concentrations of silver grains had been sectioned at points where they were naked of Schwann cell sheath, were dilated into varicosities, and contained small granular vesicles. This finding was taken as confirmatory circumstantial evidence that the small granular vesicles were the sites of uptake and storage of NE. The short interval between the start of infusion and the fixation of the tissue appeared to rule out any process other than a direct uptake of NE by the peripheral axons. If axonal sites of uptake of NE-(3)H correspond to sites of release of NE, then the evidence suggests that such sites of release are widespread over the terminal part of the axon and are not confined to those parts of the axon which are in close contact with smooth muscle cells. Since the fixation and embedding procedures will remove NE which is not strongly bound to tissues, the localization of NE-(3)H in the radioautographs does not necessarily correspond to the distribution of all the NE present in vivo.


Asunto(s)
Axones/metabolismo , Intestinos/irrigación sanguínea , Arterias Mesentéricas/inervación , Norepinefrina/metabolismo , Animales , Autorradiografía , Ratas , Sistema Nervioso Simpático , Tritio
9.
J Cell Biol ; 137(4): 835-45, 1997 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-9151686

RESUMEN

We have recently shown that two proteins related to two of the adaptor subunits of clathrincoated vesicles, p47 (mu3) and beta-NAP (beta3B), are part of an adaptor-like complex not associated with clathrin (Simpson, F., N.A. Bright, M.A. West, L.S. Newman, R.B. Darnell, and M.S. Robinson, 1996. J. Cell Biol. 133:749-760). In the present study we have searched the EST database and have identified, cloned, and sequenced a ubiquitously expressed homologue of beta-NAP, beta3A, as well as homologues of the alpha/gamma and sigma adaptor subunits, delta and sigma3, which are also ubiquitously expressed. Antibodies raised against recombinant delta and sigma3 show that they are the other two subunits of the adaptor-like complex. We are calling this complex AP-3, a name that has also been used for the neuronalspecific phosphoprotein AP180, but we feel that it is a more appropriate designation for an adaptor-related heterotetramer. Immunofluorescence using anti-delta antibodies reveals that the AP-3 complex is associated with the Golgi region of the cell as well as with more peripheral structures. These peripheral structures show only limited colocalization with endosomal markers and may correspond to a postTGN biosynthetic compartment. The delta subunit is closely related to the protein product of the Drosophila garnet gene, which when mutated results in reduced pigmentation of the eyes and other tissues. Because pigment granules are believed to be similar to lysosomes, this suggests either that the AP-3 complex may be directly involved in trafficking to lysosomes or alternatively that it may be involved in another pathway, but that missorting in that pathway may indirectly lead to defects in pigment granules.


Asunto(s)
Subunidades beta de Complejo de Proteína Adaptadora , Proteínas Portadoras/fisiología , Clatrina/fisiología , Proteínas de la Membrana/fisiología , Proteínas de Ensamble de Clatrina Monoméricas , Proteínas del Tejido Nervioso/fisiología , Fosfoproteínas/fisiología , Complejo 3 de Proteína Adaptadora , Subunidades alfa de Complejo de Proteína Adaptadora , Subunidades gamma de Complejo de Proteína Adaptadora , Proteínas Adaptadoras del Transporte Vesicular , Secuencia de Aminoácidos , Animales , Clonación Molecular , Drosophila melanogaster , Técnica del Anticuerpo Fluorescente Indirecta , Expresión Génica , Genes de Insecto , Humanos , Ratones , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/metabolismo , ARN Mensajero/genética , Ratas , Homología de Secuencia de Aminoácido , Distribución Tisular
10.
J Cell Biol ; 133(4): 749-60, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8666661

RESUMEN

Coat proteins are required for the budding of the transport vesicles that mediate membrane traffic pathways, but for many pathways such proteins pathways, but for many pathways such proteins have not yet been identified. We have raised antibodies against p47, a homologue of the medium chains of the adaptor complexes of clathrin-coated vesicles (Pevsner, J., W. Volknandt, B.R. Wong, and R.H. Scheller. 1994. Gene (Amst.). 146:279-283), to determine whether this protein might be a component of a new type of coat. p47 coimmunoprecipitates with three other proteins: two unknown proteins of 160 and 25 kD, and beta-NAP, a homologue of the beta/beta'-adaptins, indicating that it is a subunit of an adaptor-like heterotetrameric complex. However, p47 is not enriched in preparations of clathrin-coated vesicles. Recruitment of the p47-containing complex onto cell membranes is stimulated by GTP gamma S and blocked by brefeldin A, indicating that, like other coat proteins, its membrane association is regulated by an ARF. The newly recruited complex is localized to non-clathrin-coated buds and vesicles associated with the TGN. Endogenous complex in primary cultures of neuronal cells is also localized to the TGN, and in addition, some complex is associated with the plasma membrane. These results indicate that the complex is a component of a novel type of coat that facilitates the budding of vesicles from the TGN, possibly for transporting newly synthesized proteins to the plasma membrane.


Asunto(s)
Subunidades beta de Complejo de Proteína Adaptadora , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Complejo 3 de Proteína Adaptadora , Animales , Secuencia de Bases , Línea Celular , Membrana Celular , Clatrina/metabolismo , ARN Helicasas DEAD-box , Cartilla de ADN , Técnicas Inmunológicas , Datos de Secuencia Molecular , Células PC12 , Conejos , Ratas
11.
Science ; 224(4653): 1095-7, 1984 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-6585956

RESUMEN

The effect of a partial pressure of nitrogen of 50 atmospheres (5065 kilopascals ) on the hydrogen evolution reaction of nitrogenase has been investigated. Evolution of hydrogen was not blocked completely by 50 atmospheres of nitrogen in any of four experiments; rather, 27.3 +/- 2.4 percent of the total electron flux through nitrogenase was directed toward production of hydrogen. The ratio of hydrogen evolved to nitrogen fixed was close to 1:1, which implies that hydrogen evolution is obligatory in the fixation of molecular nitrogen by nitrogenase.


Asunto(s)
Hidrógeno , Nitrógeno , Nitrogenasa , Fenómenos Químicos , Química , Fijación del Nitrógeno , Presión Parcial
12.
Science ; 156(3775): 656-7, 1967 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-6023660

RESUMEN

The technique of " freezeetching" tissues for electron microscopy has permitted observation of the external apertures of the transverse tubules. The apertures appear on the cell surface in approximately parallel rows, which can be interpreted as corresponding longitudinally to the spaces between the myofibrils and transversely to the Z regions of the myofibrils.


Asunto(s)
Miocardio/citología , Organoides , Animales , Cobayas , Microscopía Electrónica , Miofibrillas
13.
Anaesthesia ; 68(5): 538-40, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23573857
14.
Curr Biol ; 8(25): 1399-402, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9889104

RESUMEN

Receptor-mediated endocytosis via clathrin-coated vesicles has been extensively studied and, while many of the protein players have been identified, much remains unknown about the regulation of coat assembly and the mechanisms that drive vesicle formation [1]. Some components of the endocytic machinery interact with inositol polyphosphates and inositol lipids in vitro, implying a role for phosphatidylinositols in vivo [2] [3]. Specifically, the adaptor protein complex AP2 binds phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2), PtdIns(3)P, PtdIns(3,4,5)P3 and inositol phosphates. Phosphatidylinositol binding regulates AP2 self-assembly and the interactions of AP2 complexes with clathrin and with peptides containing endocytic motifs [4] [5]. The GTPase dynamin contains a pleckstrin homology (PH) domain that binds PtdIns(4,5)P2 and PtdIns(3,4,5)P3 to regulate GTPase activity in vitro [6] [7]. However, no direct evidence for the involvement of phosphatidylinositols in clathrin-mediated endocytosis exists to date. Using well-characterized PH domains as high affinity and high specificity probes in combination with a perforated cell assay that reconstitutes coated vesicle formation, we provide the first direct evidence that PtdIns(4,5)P2 is required for both early and late events in endocytic coated vesicle formation.


Asunto(s)
Endosomas/metabolismo , Fosfatidilinositol 4,5-Difosfato/fisiología , Complejo 2 de Proteína Adaptadora , Proteínas Adaptadoras del Transporte Vesicular , Biotina/metabolismo , Membrana Celular/metabolismo , Clatrina/metabolismo , Endocitosis/efectos de los fármacos , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Mutagénesis , Neomicina/farmacología , Proteínas del Tejido Nervioso/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipasa C delta , Fosfoproteínas/metabolismo , Unión Proteica/efectos de los fármacos , Unión Proteica/genética , Transferrina/metabolismo , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/genética , Fosfolipasas de Tipo C/metabolismo
15.
J Dermatolog Treat ; 27(2): 167-72, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26270468

RESUMEN

INTRODUCTION: Laser therapy is one of the most promising device-based therapies for onychomycosis. To date, reported clinical efficacies, as well as anecdotal clinical results, have varied greatly, and the specific mechanism of action has not been well-elucidated. METHODS: Here, we provide an overview of the mechanisms of action and detailed analysis of the technical parameters involved in creating a laser that will be successfully fungicidal in onychomycosis. RESULTS: This review provides important insight into why the efficacies of laser studies reported to date vary so greatly and what is critical in order to obtain high efficacy in the clinical treatment of onychomycosis. CONCLUSIONS: There is substantial opportunity to improve the targeting and anti-targeting properties of lasers to address the specific considerations required to treat onychomycosis and, more generally, other dermal pathogens.


Asunto(s)
Terapia por Láser/métodos , Onicomicosis/terapia , Humanos , Terapia por Láser/tendencias
16.
Exp Hematol ; 23(13): 1407-16, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7498370

RESUMEN

Although macrophages account for 70-90% of the adherent cells in mouse long-term bone marrow cultures (LTBMC) and CFU-F colonies, the predominant nonhematopoietic stromal cell is endothelial-like (EL), expressing cytoplasmic collagen IV, laminin, and an antigen recognized by the monoclonal antibody MECA-10. We report the isolation of this stromal cell lineage from primary LTBMC by immunomagnetic cell selection using MECA-10. More than 95% of the cells in the MECA-10-positive fraction are EL cells as judged by morphology, surface staining for MECA-10, cytoplasmic staining for collagen IV, and electrophoretic analysis of MECA-10-positive cells isolated from radiation chimeras. When plated under LTBMC conditions, EL cell monolayers recharged with either wild-type or Sl/Sld marrow support an increased density and number of clonogenic and mature hematopoietic cells in short-term cultures. In accord with this finding, Northern blots of mRNA from unstimulated EL cells demonstrate constitutive expression of Kit ligand (KL). Moreover, in situ two-color immunofluorescence staining for cytoplasmic collagen IV and surface KL suggests that EL cells are the exclusive source of membrane-bound KL in mouse cultures. The ability to isolate EL cells from primary cultures without the need for repeated cell passage or immortalization provides a novel approach to dissecting the molecular basis of stem cell-stromal cell interactions.


Asunto(s)
Células de la Médula Ósea , Células del Tejido Conectivo , Endotelio/citología , Hematopoyesis , Separación Inmunomagnética , Factor de Células Madre/biosíntesis , Animales , Anticuerpos Monoclonales/inmunología , Linaje de la Célula , Células Cultivadas , Colágeno/biosíntesis , Ensayo de Unidades Formadoras de Colonias , Endotelio/inmunología , Femenino , Expresión Génica , Factor Estimulante de Colonias de Macrófagos/biosíntesis , Factor Estimulante de Colonias de Macrófagos/genética , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Mutantes , Quimera por Radiación , Factor de Células Madre/genética
17.
Clin Pharmacol Ther ; 20(2): 138-41, 1976 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7374

RESUMEN

A double-blind placebo crossover trail (2 periods, each of 6 wk) was carried out in 12 patients. In the first period the patients were randomly allocated to either their individual established dose of prazosin or to the same number of placebo tablets; treatment was reversed after 6 wk. Blood pressure was higher by 17/8 mm Hgin the lying posture and by 24/14 mm Hg in the standing posture during placebo than during prazosin treatment. Standing pulse rate and body weight were higher and plasma renin activity lower during prazosin treatment. Postural hypotension occurring 1 to 2 hr after the first few doses was noted in one third of the patients when they resumed prazosin treatment after the placebo course.


Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Quinazolinas/uso terapéutico , Antagonistas Adrenérgicos beta/uso terapéutico , Adulto , Anciano , Presión Sanguínea , Peso Corporal , Ensayos Clínicos como Asunto , Diuréticos/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Piperazinas/uso terapéutico , Placebos , Pulso Arterial , Renina/sangre , Factores de Tiempo
18.
J Hypertens ; 14(6): 683-9, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8793689

RESUMEN

It has been suggested that selection for antihypertensive therapy should be based on absolute risk of a cardiovascular disease (CVD) event and that treatment should be offered only if the 10-year risk exceeds 20%. Although interesting and challenging, this strategy would have the effect of greatly emphasizing treatment of the elderly and downplaying treatment of the middle-aged. It is argued in this paper that the use of one and the same time-frame for all age groups is illogical; some inverse age-related adjustment is needed. In addition, it is suggested that selection for active treatment would be better based not on the total absolute risk of CVD but rather on the marginal hypertensive risk (i.e. that part of the total risk which can be attributed to raised blood pressure). Problems in the use of antihypertensive drugs in people with 'high normal' blood pressure in order to compensate for risk factors such as obesity, hyperlipidaemia and smoking are discussed. The effect of antihypertensive treatment administered in large-scale trials to the most hypertensive control subjects has been (and continues to be) largely ignored; it should be taken into account in all calculations in this field. A policy based on absolute risk is certainly worth examining but it should not be considered self-evidently correct and needs testing in all its aspects before it is adopted on a large scale.


Asunto(s)
Antihipertensivos/uso terapéutico , Enfermedades Cardiovasculares , Guías como Asunto , Envejecimiento/fisiología , Presión Sanguínea , Humanos , Nueva Zelanda , Factores de Riesgo , Factores de Tiempo
19.
J Hypertens ; 2(2): 163-70, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6533184

RESUMEN

The handling of an intraperitoneal salt (NaCl) load (about 10% of body Na) was studied by means of a whole-body counting method using 22Na in four strains of rat: spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto rats (WKY), New Zealand genetically hypertensive rats (GH), and outbred normotensive rats (N). The rats had previously been equilibrated so that their body Na was of the same specific activity as the injected NaCl. The load was given first at 10 weeks of age, while the rats had a choice of water and 0.5% NaCl to drink, and again at 13 weeks when the rats had a choice of water and 0.04% NaCl. All the strains excreted the load more slowly when on the low Na intake. The SHR excreted the load most quickly and the WKY most slowly. There was no difference between the GH and N rats in this respect. The SHR differed from the other strains in having an increased appetite for salt and an increased total body sodium relative to body weight.


Asunto(s)
Dieta Hiposódica , Hipertensión/metabolismo , Sodio/administración & dosificación , Animales , Masculino , Distribución Aleatoria , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas , Ratas Endogámicas WKY , Sodio/metabolismo , Cloruro de Sodio/administración & dosificación , Factores de Tiempo
20.
J Hypertens ; 19(3 Pt 2): 535-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11327626

RESUMEN

OBJECTIVE: Having found no definite relationship between blood pressure (BP) and 24h sodium excretion in women aged 48-56 years (in contrast to the results in men of the same age) in the WHO Cardiovascular Diseases and Alimentary Comparison (WHO-CARDIAC) Study, we analyzed the data to investigate whether the sodium-BP association differed between pre- and post-menopausal women. DESIGN AND METHODS: The WHO-CARDIAC is a multicenter cross-sectional study, involving, as of July 2000, 60 collaborating centers in 25 countries. In each center, 100 men and 100 women aged 48-56 years were selected randomly from the general population of the area. In this report, 2,212 women in 21 centers located in 17 countries worldwide, who had data on menopausal status, were studied. RESULTS: After adjustment for age, body mass index (BMI) and 24h urinary potassium excretion, 24h sodium excretion was positively and significantly associated with systolic blood pressure (SBP) [pooled regression coefficient: 0.037 (SE 0.01), P < 0.01] and with diastolic blood pressure (DBP) [0.023 (0.006), P< 0.01] in post-menopausal women. Pooled regression coefficients of sodium-BP association were not significant in pre-menopausal women (P< 0.05). Cross-center correlation analyses of the 21 centers showed that 24h sodium excretion was positively associated with SBP and DBP in both pre- and post-menopausal women, and this positive association between sodium excretion and SBP was significant in post-menopausal women (R2 = 0.23, P = 0.029). CONCLUSION: Different associations between sodium and BP were observed in women with pre- and post-menopausal status. There may be a tendency for salt sensitivity to increase at the menopause.


Asunto(s)
Presión Sanguínea , Ritmo Circadiano , Natriuresis , Posmenopausia/fisiología , Premenopausia/fisiología , Estudios Transversales , Diástole , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sístole
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