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1.
Ecology ; 98(5): 1475, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28263380

RESUMEN

Animals can be important in modulating ecosystem-level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology (MTE) and ecological stoichiometry (ES). They also represent an important set of functional traits that may reflect both environmental and phylogenetic influences. Over the past two decades, studies of animal-mediated nutrient cycling have increased dramatically, especially in aquatic ecosystems. Here we present a global compilation of aquatic animal nutrient excretion rates. The dataset includes 10,534 observations from freshwater and marine animals of N and/or P excretion rates. These observations represent 491 species, including most aquatic phyla. Coverage varies greatly among phyla and other taxonomic levels. The dataset includes information on animal body size, ambient temperature, taxonomic affiliations, and animal body N:P. This data set was used to test predictions of MTE and ES, as described in Vanni and McIntyre (2016; Ecology DOI: 10.1002/ecy.1582).


Asunto(s)
Organismos Acuáticos/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Animales , Ecosistema , Agua Dulce , Filogenia
2.
Osteoporos Int ; 25(1): 141-50, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24196722

RESUMEN

UNLABELLED: The present meta-analysis shows no clear association between coffee consumption and the risk of hip fractures. There was a nonlinear association between tea consumption and the risk of hip fracture. Compared to no tea consumption, drinking 1-4 cups of tea daily was associated with a lower risk of hip fracture. INTRODUCTION: Prospective cohort and case-control studies have suggested that coffee and tea consumption may be associated with the risk of hip fracture; the results have, however, been inconsistent. We conducted a meta-analysis to assess the association between coffee and tea consumption and the risk of hip fracture. METHODS: We performed systematic searches using MEDLINE, EMBASE, and OVID until February 20, 2013, without limits of language or publication year. Relative risks (RRs) with 95% confidence intervals (CI) were derived using random-effects models throughout all analyses. We conducted categorical, dose-response, heterogeneity, publication bias, and subgroup analyses. RESULTS: Our study was based on 195,992 individuals with 9,958 cases of hip fractures from 14 studies, including six cohort and eight case-control studies. The pooled RRs of hip fractures for the highest vs. the lowest categories of coffee and tea consumption were 0.94 (95% CI 0.71-1.17) and 0.84 (95% CI 0.66-1.02), respectively. For the dose-response analysis, we found evidence of a nonlinear association between tea consumption and the risk of hip fracture (p(nonlinearity) < 0.01). Compared to no tea consumption, 1-4 cups of tea per day may reduce the risk of hip fracture by 28% (0.72; 95% CI 0.56-0.88 for 1-2 cups/day), 37% (0.63; 95% CI 0.32-0.94 for 2-3 cups/day), and 21% (0.79; 95% CI 0.62-0.96 for 3-4 cups/day). CONCLUSIONS: We found no significant association between coffee consumption and the risk of hip fracture. A nonlinear association emerged between tea consumption and the risk of hip fracture; individuals drinking 1-4 cups of tea per day exhibited a lower risk of hip fractures than those who drank no tea. The association between 5 daily cups of tea, or more, and hip fracture risk should be investigated.


Asunto(s)
Café/efectos adversos , Fracturas de Cadera/etiología , Fracturas Osteoporóticas/etiología , Té/efectos adversos , Fracturas de Cadera/prevención & control , Humanos , Fracturas Osteoporóticas/prevención & control , Factores de Riesgo
3.
Br J Pharmacol ; 171(3): 663-75, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24125472

RESUMEN

BACKGROUND AND PURPOSE: Osteoclasts play a pivotal role in diseases such as osteoporosis, rheumatoid arthritis and tumour bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. Here, we examined changes in osteoclastogenesis and LPS-induced osteolysis in response to andrographolide (AP), a diterpenoid lactone isolated from the traditional Chinese and Indian medicinal plant Andrographis paniculata. EXPERIMENTAL APPROACH: Effects of AP on osteoclast differentiation and bone resorption were measured in vitro. Western blots and RT-PCR techniques were used to examine the underlying molecular mechanisms. The bone protective activity of AP in vivo was assessed in a mouse model of osteolysis. KEY RESULTS: AP concentration-dependently suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro and reduced the expression of osteoclast-specific markers, including tartrate-resistant acid phosphatase, calcitonin receptors and cathepsin K. Further molecular analysis revealed that AP impaired RANKL-induced NF-κB signalling by inhibiting the phosphorylation of TGF-ß-activated kinase 1, suppressing the phosphorylation and degradation of IκBα, and subsequently preventing the nuclear translocation of the NF-κB p65 subunit. AP also inhibited the ERK/MAPK signalling pathway without affecting p38 or JNK signalling. CONCLUSIONS AND IMPLICATIONS: AP suppressed RANKL-induced osteoclastogenesis through attenuating NF-κB and ERK/MAPK signalling pathways in vitro, thus preventing bone loss in vivo. These data indicated that AP is a promising natural compound for the treatment of osteoclast-related bone diseases.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Modelos Animales de Enfermedad , Diterpenos/uso terapéutico , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteólisis/prevención & control , Ligando RANK/antagonistas & inhibidores , Animales , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Biomarcadores/metabolismo , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/farmacología , Células de la Médula Ósea/citología , Huesos/efectos de los fármacos , Huesos/inmunología , Huesos/patología , Células Cultivadas , Diterpenos/farmacología , Regulación hacia Abajo/efectos de los fármacos , Femenino , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/citología , Ratones , Ratones Endogámicos C57BL , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Osteoclastos/inmunología , Osteoclastos/metabolismo , Osteoclastos/patología , Osteólisis/inducido químicamente , Osteólisis/inmunología , Osteólisis/patología , Ligando RANK/genética , Ligando RANK/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
Int J Biochem Cell Biol ; 44(9): 1422-35, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22652318

RESUMEN

The vacuolar-type H(+)-ATPase (V-ATPase) proton pump is a macromolecular complex composed of at least 14 subunits organized into two functional domains, V(1) and V(0). The complex is located on the ruffled border plasma membrane of bone-resorbing osteoclasts, mediating extracellular acidification for bone demineralization during bone resorption. Genetic studies from mice to man implicate a critical role for V-ATPase subunits in osteoclast-related diseases including osteopetrosis and osteoporosis. Thus, the V-ATPase complex is a potential molecular target for the development of novel anti-resorptive agents useful for the treatment of osteolytic diseases. Here, we review the current structure and function of V-ATPase subunits, emphasizing their exquisite roles in osteoclastic function. In addition, we compare several distinct classes of V-ATPase inhibitors with specific inhibitory effects on osteoclasts. Understanding the structure-function relationship of the osteoclast V-ATPase may lead to the development of osteoclast-specific V-ATPase inhibitors that may serve as alternative therapies for the treatment of osteolytic diseases.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Osteoclastos/enzimología , ATPasas de Translocación de Protón Vacuolares/química , ATPasas de Translocación de Protón Vacuolares/metabolismo , Animales , Inhibidores Enzimáticos/uso terapéutico , Humanos , Osteoclastos/efectos de los fármacos , Especificidad por Sustrato , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores
5.
Osteoporos Int ; 23(4): 1317-27, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21505910

RESUMEN

UNLABELLED: This multicenter and randomized clinical trial showed that daily oral herbal formula Xian Ling Gu Bao (XLGB) was safe in postmenopausal women over a 1-year treatment. Those patients (n ∼ 50) treated with XLGB at the conventional dose demonstrated a statistically significant increase in dual-energy X-ray absorptiometry (DXA) bone mineral density (BMD) at lumbar spine at 6 months and a numerically increased BMD at 12 months. INTRODUCTION: The aim of this study was to examine the safety and efficacy of a herbal formula XLGB in postmenopausal women (ChiCTR-TRC-00000347). METHODS: One hundred eighty healthy postmenopausal women (≥60 years old) with BMD T-score ≤ -2.0 (lumbar spine or femoral neck) were recruited from four clinical centers to receive low-dose (conventional dose) XLGB (L-XLGB group, 3 g/day, n = 61) or high-dose XLGB (H-XLGB group, 6 g/day, n = 58) or placebo (CON group, n = 61). Women received daily calcium (500 mg) and vitamin D (200 IU) supplementation. Primary endpoints were lumbar spine BMD and safety; secondary endpoints were femoral neck BMD and bone turnover markers measured at baseline and at 6 and 12 months. RESULTS: Of 180 women recruited, 148 completed the study. The compliance in each group was comparable. Prominent adverse events were not observed in either group. In the L-XLGB group at 6 months, lumbar spine BMD by DXA increased significantly from baseline (+2.11% versus CON +0.58%, p < 0.05), but femoral neck BMD did not; at 12 months, BMD in the L-XLGB group decreased from 6-month levels yet remained higher than baseline, but without difference from the CON group. There was no dose-dependent response. Bone turnover marker levels declined during the first 6 months after XLGB treatment. There was no significant difference in the overall incidence of side effects among treatment and control groups. CONCLUSION: XLGB over 1-year treatment at the conventional dose demonstrated safe and only a statistically significant increase in BMD at lumbar spine at 6 months in postmenopausal women.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Absorciometría de Fotón/métodos , Anciano , Biomarcadores/sangre , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/fisiología , Método Doble Ciego , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Cuello Femoral/fisiopatología , Humanos , Vértebras Lumbares/fisiopatología , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Osteocalcina/sangre , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/fisiopatología , Resultado del Tratamiento
6.
Zhonghua Wai Ke Za Zhi ; 38(1): 47-50, 2000 Jan.
Artículo en Chino | MEDLINE | ID: mdl-11831987

RESUMEN

OBJECTIVE: To study the effects of recombinant human growth hormone on cortical bone of middle femur and vertebra of variectomized rats. METHODS: Forty 6 month-old SD rats received low or high dose of growth hormone subcutaneously 3 months after ovariectomy for 8 weeks. Bone density and biomechanical strength of the femur were measured, and the thickness of cortical bone of the middle femur and L(2) vertebra was observed. The results were compared with those in estrogen group. RESULTS: Growth hormone increased the thickness of cortical bone and biomechanical strength and bone density. Estrogen therapy showed no effects on bone density and biomechanical strength of cortical bone. CONCLUSION: Recombinant human growth hormone can prevent bone loss from cortical bone of ovariectomized rat.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Hormona de Crecimiento Humana/farmacología , Animales , Fenómenos Biomecánicos , Huesos/fisiología , Femenino , Humanos , Ovariectomía , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología
7.
J Mol Cell Cardiol ; 30(11): 2365-75, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9925372

RESUMEN

Seven types of zinc finger protein (ZFP) genes based on the combinations of cysteine and histidine residues were found in a human heart cDNA database. Here we report the isolation of 360 cDNA clones encoding putative ZFPs. Of these, 154 (42.8%) represent C2H2-type ZFPs, 101 (28.1%) represent C2C2-type, five (1.4%) represent C2HC-type, 71 (19.7%) represent C2HC4C(HD)-type, three (0.8%) represent C3H-type, eight (2.2%) represent C3HC4-type and 18 (0.5%) represent combination type (genes containing more than one type of zinc finger). Among these 360 ZFPs, a novel ZFP cDNA named HFHZ (human fetal heart ZFP) with sequence homology to a Kruppel-associated box (KRAB) was identified. Sequencing the full-length of this cDNA clone identified an open reading frame of 711 bp that encodes a 237 amino acid protein with a predicted molecular weight of 27.7 kDa. Sequence analysis indicated that HFHZ contained a truncated KRAB box at the N-terminus and two C2H2 zinc fingers at the C-terminus. The transcript of HFHZ is highly expressed in fetal heart and moderately expressed in fetal brain but not expressed in fetal liver as revealed by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis suggesting that HFHZ is not expressed ubiquitously. The 3.3-fold higher expression in the fetal heart than in the adult heart suggests that HFHZ mRNA is downregulated in the process of development. In addition, the relatively high expression (1.9-fold) of HFHZ observed in the hypertrophic as compared to the normal adult heart suggests that this fetal gene is reactivated in response to hypertrophic stimuli. Chromosomal localization by in situ hybridization revealed that this gene is in 19q13.1, a region containing genes involved in both cell cycle and developmental regulation.


Asunto(s)
Cromosomas Humanos Par 19 , ADN Complementario/genética , Regulación de la Expresión Génica , Expresión Génica , Miocardio/metabolismo , Dedos de Zinc/genética , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Cardiomegalia/genética , Mapeo Cromosómico , ADN Complementario/análisis , Corazón/embriología , Humanos , Datos de Secuencia Molecular , Alineación de Secuencia , Análisis de Secuencia de ADN
8.
J Biomech Eng ; 107(3): 268-73, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4046568

RESUMEN

The hypothesis is made that a disturbance in blood flow at one place can be detected in the arterial pulse waves at a distant site. This hypothesis was motivated by the traditional Chinese medicine which uses arterial pulse waves as a principal means of diagnosis. We formulated a test by asking whether a disturbance to the blood flow in a leg can be detected by changes in the pulse waves in the radial arteries. In particular, we ask whether the radial artery can differentiate a disturbance in the right leg from that in the left leg. We put force transducers on the radial arteries, depressed them by a specific amount, and recorded the force waves in response to a 2-min occlusion of the blood flow in the right or left tibial artery. The results show that the radial artery force waves do change in response to the flow disturbance. For a given individual, the force varies with the location of the force transducer on the radial artery, the specific amount of initial depression, and the right or left leg occlusion. Generally, an occlusion in the right leg reduces the force level in both radial arteries, the more so in the right radial artery than in the left. Although the discrimination is not very strong, the phenomenon is novel, and warrants further investigation.


Asunto(s)
Antebrazo/irrigación sanguínea , Pierna/irrigación sanguínea , Medicina Tradicional China , Medicina Tradicional de Asia Oriental , Pulso Arterial , Adulto , Arterias/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional , Transductores de Presión
9.
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