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1.
Heliyon ; 9(8): e19019, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37636437

RESUMO

The role that owner-managers' managerial capabilities play in agricultural firms' strategic change and performance is still unclear. A firm's market opportunities seizing capability (OSC) is a source of competitiveness and superior performance. The objective of this study is to establish how owner-manager's dynamic managerial capabilities (DMCs) including managerial human capital, managerial social capital and managerial cognition affect firm performance through the mediating effect of OSC, as well as the moderating effect of market dynamism in the relationship OSC and firm performance. 306 cross-sectional data collected at fish farming firms (FFF) level in southern Benin were used and partial least squares structural equation model was applied to test research hypotheses. The results of SmartPLS4 reveal that owner-managers' DMCs including business ties (BTs), political ties (PTs), and managerial cognition (MC) demonstrate a significant effect at improving FFF market OSC and performance. Finding also underline the significant contribution of market dynamism to FFF performance as well the mediating role of market OSC in the relationship between BTs, PTs, MC, and FFF performance. Findings suggest that FFF owner-managers can achieve superior performance by strengthening their DMCs while improving market OSC. The study provides useful insights to FFF owner-managers, agriculture policymakers and practitioners who are engaged in agriculture firms' strategic management and sustainable performance.

2.
Am J Primatol ; 77(9): 1015-1025, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26118671

RESUMO

A small chimpanzee habitat in the montane forest of Kahuzi-Biega National Park, Democratic Republic of Congo, is connected with the lowland forest of this park through a corridor, which is affected by human encroachment. To assess the conservation status of the chimpanzee population in this small habitat, we estimated the size of the community and evaluated its genetic diversity by using 279 fecal samples collected in the montane forest of Kahuzi. Using autosomal microsatellite (or short tandem repeat, STR) loci, we identified 32 individuals, comprising 19 females and 13 males. Samples from 24 individuals were collected at least twice and a genetic mark-recapture analysis estimated that the community size was 36 (range: 32-42). Data on nest site sharing confirmed that all the samples belonged to the same community. Nest site sharing information may be useful in population studies of unhabituated chimpanzees. The genetic structure and diversity of the 32 genotyped individuals was assessed using Y-chromosomal short tandem repeat (Y-STR) loci and mitochondrial D-loops. One dominant Y-STR haplotype was found, whereas there was no dominant haplotype in the mitochondrial region, reflecting a female-biased dispersal pattern, which is typical of chimpanzees. The genetic diversity for three markers in Kahuzi chimpanzees was comparable to that in other eastern chimpanzee populations. A relatively high heterozygosity and negative inbreeding coefficient (FIS ) for STR loci suggests that the study community belongs to an outbreeding chimpanzee population. These findings suggest that individuals of the study community may have reproductive contact with other chimpanzee individuals from neighboring communities in Kahuzi-Biega National Park, at least in the recent past. Am. J. Primatol. 77:1015-1025, 2015. © 2015 Wiley Periodicals, Inc.

3.
Artigo em Inglês | MEDLINE | ID: mdl-22654214

RESUMO

This study was carried to examine the effects of the aqueous leaf extract of Sesamum radiatum, a laxative plant on the contractile activity of Taenia caeci, an intestinal smooth muscle. Strips of Taenia caeci were rapidly removed from guinea-pig and were suspended between two L-shaped stainless steel hooks in a 10 ml organ bath with Mac Ewen solution. The isometric contractile force of the Taenia caeci strips were recorded by using a strain gauge. S. radiatum aqueous leaf extract (ESera) is a spasmogenic substance. This myostimulant effect is characterized by the increase of the rhythm and the amplitude of isolated guinea-pig Taenia caeci smooth muscle in normal solution and by the development of contracture in modified solution and in solution without calcium. A similar effect was observed with ACh which caused a graded increase of the contractile activity of Taenia caeci. The effects induced by ESera and ACh were reversed in the presence of atropine. The spasmogenic effect induced by ESera could justify partially the use of S. radiatum as laxative in traditional medicine.


Assuntos
Ceco/efeitos dos fármacos , Contração Isométrica/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sesamum/química , Acetilcolina/antagonistas & inibidores , Animais , Atropina/farmacologia , Cálcio/farmacologia , Ceco/fisiologia , Relação Dose-Resposta a Droga , Feminino , Cobaias , Técnicas In Vitro , Masculino , Antagonistas Muscarínicos , Músculo Liso/fisiologia , Folhas de Planta/química , Potássio/farmacologia
4.
J Physiol Pharmacol ; 60(3): 103-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19826188

RESUMO

Green tea catechins (GTC) have been shown to inhibit the activities of enzymes involved in folate uptake. Hence, regular green tea drinkers may be at risk of impaired folate status. The present experiments aimed at studying the impact of dietary GTC on folate concentrations and metabolism. In a human pilot study (parallel design) healthy men consumed for 3 weeks 6 capsules (approximately 670 mg GTC) per day (2 capsules with each principal meal) containing aqueous extracts of the leaves of Camellia sinensis (n=17) or placebo (n=16). No differences in plasma folate concentrations were observed between treatments. We further fed groups of 10 male rats diets fortified with 0, 0.05, 0.5, 1, or 5 g GTC/kg for 6 weeks. Only at the highest intake, GTC significantly decreased serum 5-methyl-tetrahydrofolate concentrations in rats, while mRNA concentrations of reduced folate carrier, proton-coupled folate transporter/heme carrier protein 1, and dihydrofolate reductase (DHFR) remained unchanged in intestinal mucosa. Using an in vitro enzyme activity assay, we observed a time- and dose-dependent inhibition of DHFR activity by epigallocatechin gallate and a green tea extract. Our data suggest that regular green tea consumption is unlikely to impair folate status in healthy males, despite the DHFR inhibitory activity of GTC.


Assuntos
Camellia sinensis/química , Catequina/efeitos adversos , Antagonistas do Ácido Fólico/efeitos adversos , Ácido Fólico/sangue , Extratos Vegetais/efeitos adversos , Adolescente , Adulto , Animais , Catequina/administração & dosagem , Catequina/isolamento & purificação , Catequina/farmacologia , Cromatografia Líquida de Alta Pressão , Dieta , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ácido Fólico/administração & dosagem , Ácido Fólico/biossíntese , Antagonistas do Ácido Fólico/administração & dosagem , Antagonistas do Ácido Fólico/isolamento & purificação , Antagonistas do Ácido Fólico/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Inquéritos e Questionários , Tetra-Hidrofolato Desidrogenase/biossíntese , Adulto Jovem
5.
Bone Marrow Transplant ; 44(1): 13-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19139740

RESUMO

The application of myeloablative Allo-SCT is limited by its associated morbidity and mortality. Reduced-intensity conditioning regimens attempt to diminish these, but are associated with a higher risk of disease relapse. Given the evidence of activity of clofarabine and cytarabine in myelodysplastic syndrome/acute myeloid leukemia (MDS/AML), we explored a novel reduced-intensity conditioning regimen based on this backbone. Patients received clofarabine 40 mg/m(2) i.v. on days -6 to -2, cytarabine 1 g/m(2) i.v. on days -6 to -2 and anti-thymocyte globulin (ATG) 1 mg/kg on day -4 and 2.5 mg/kg x 2 days on days -3 and -2. Seven patients were enrolled. Their median age was 54 years; three were with MDS and four with AML. The median duration of neutropenia was 14 days and that of thrombocytopenia was 22 days. Toxicities included hand-foot syndrome (57% grade 2), elevated alanine aminotransferase (ALT) (57% grade 3), elevated aspartate aminotransferase (AST) (86% grade 3) and hyperbilirubinemia (29% grade 3-5). No acute GVHD was observed. Enrollment to the trial was halted after three of the first seven patients expired on days +15, +26 and +32. Three of the four surviving patients have relapsed with a median TTP of 152 days. This regimen was not sufficiently immunosuppressive to ensure engraftment, and was associated with substantial morbidity and mortality.


Assuntos
Nucleotídeos de Adenina/administração & dosagem , Soro Antilinfocitário/administração & dosagem , Antimetabólitos Antineoplásicos/administração & dosagem , Arabinonucleosídeos/administração & dosagem , Citarabina/administração & dosagem , Imunossupressores/administração & dosagem , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicas/terapia , Transplante de Células-Tronco , Condicionamento Pré-Transplante/métodos , Nucleotídeos de Adenina/efeitos adversos , Adulto , Idoso , Soro Antilinfocitário/efeitos adversos , Antimetabólitos Antineoplásicos/efeitos adversos , Arabinonucleosídeos/efeitos adversos , Clofarabina , Citarabina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Imunossupressores/efeitos adversos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Taxa de Sobrevida , Fatores de Tempo , Transplante Homólogo
6.
J Anim Physiol Anim Nutr (Berl) ; 92(6): 705-11, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19012616

RESUMO

Supplementation of pigs with vitamin E, the most important lipid-soluble antioxidant, has been shown to improve meat quality and animal health. Previous studies in cultured cells and laboratory animals indicate synergistic effects between polyphenols and vitamin E. The present feeding trial was undertaken to investigate the effects of dietary green tea polyphenols (GTP) on vitamin E status, antioxidative capacity and parameters of meat quality in growing pigs. Eighteen castrated, crossbred, male pigs received a flavonoid-poor diet based on corn starch, caseinate and rapeseed oil with a total vitamin E content of 17 IU/kg diet over a period of 5 weeks. This basal diet was supplemented with green tea extract to provide daily doses of 0 (control), 10 and 100 mg GTP/kg body weight. Dietary supplementation of growing pigs with GTP did not affect serum, liver, lung and muscle vitamin E (alpha- and gamma-tocopherol) concentrations, plasma antioxidant capacity (ferric reducing ability of plasma, trolox equivalent antioxidant capacity) or parameters of meat quality including meat temperature, pH, conductivity, colour and drip loss. In conclusion, supplementation of pig diets with green tea catechins is not associated with improved antioxidant status and meat quality under practice-oriented conditions.


Assuntos
Flavonoides/farmacologia , Carne/normas , Estado Nutricional , Fenóis/farmacologia , Suínos/crescimento & desenvolvimento , Chá/química , Vitamina E/sangue , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Relação Dose-Resposta a Droga , Flavonoides/administração & dosagem , Masculino , Oxirredução , Fenóis/administração & dosagem , Polifenóis , Distribuição Aleatória , Suínos/metabolismo , Vitamina E/administração & dosagem
7.
Bone Marrow Transplant ; 38(12): 813-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17057724

RESUMO

Patients with hematologic malignancies and hematopoietic stem cell transplant (HSCT) recipients are at high risk for bacterial bloodstream infections (BSI) owing to resistant organisms. Data describing the outcomes of vancomycin-resistant enterococcal (VRE) BSI in this patient population are limited. We performed a retrospective cohort study of all cases of VRE BSI that occurred between February 1996 and December 2002 on the Leukemia/HSCT unit at Barnes-Jewish Hospital. There were 68 episodes of VRE BSI in 60 patients with acute (53%) or chronic (8%) leukemia, non-Hodgkin's lymphoma (22%) or other malignant hematologic disorders (17%). A total of 13, 32 and 32% were recipients of autologous, related and matched-unrelated transplants, respectively. Forty-two of allograft recipients had active acute graft-versus-host disease (GVHD) and 32% chronic GVHD. Only 57% were neutropenic, 52% had refractory/relapsed malignancy and 60% had end organ dysfunction with a median APACHE II score of 17. Median survival after VRE BSI was 19 days. Pneumonia, receipt of anti-fungal drugs and low APACHE II score at the time of the VRE BSI remained significant risk factors for death on multivariable analysis. Our analysis suggests that in patients with hematological malignancies or HSCT, VRE may not have the behavior of a virulent pathogen. VRE BSI may simply be a marker of these patients' already existing critical medical condition.


Assuntos
Enterococcus , Infecções por Bactérias Gram-Positivas/mortalidade , Neoplasias Hematológicas/mortalidade , Transplante de Células-Tronco Hematopoéticas , Resistência a Vancomicina , APACHE , Adulto , Idoso , Feminino , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/mortalidade , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/etiologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Autólogo , Transplante Homólogo
9.
Exp Physiol ; 86(2): 289-96, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11429646

RESUMO

The oxytocin receptor (OTR) is part of an ancient hormone system expressed in diverse phyla in relation to acute reproductive smooth muscle responses, such as egg-laying, birth, or milk letdown. The regulation of the OTR gene, while correlating with steroid levels in vivo, remains elusive. There appear to be both inhibitory and stimulatory influences acting upon a constitutive pattern of basal expression. We have found no evidence, however, for an effect of the sex steroids either directly on gene transcription, or on the receptor itself at the protein level. In the prostatic carcinoma cell line Du145, we have shown that up-regulation of the OTR gene transcription can be effected by cAMP. In an attempt to characterize the expression of the OTR protein in vivo, we have shown, using ligand-blotting, that the OTR can be expressed at different sizes in transfected cells and in myometrium. Also, in the myometrium at term, immunohistochemistry suggests that there is both an increase in OTR protein per cell, as well as in the number of smooth muscle cells expressing OTR, emphasizing that perinatal changes are the results of both individual gene activation events and gross cellular differentiation. The OTR is a valuable model system reflecting molecular changes in the perinatal period. When we understand how this important molecule is regulated, we will also be a long way towards understanding the mechanisms controlling myometrial contractility at birth. Experimental Physiology (2001) 86.2, 289-296.


Assuntos
Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Animais , Feminino , Hormônios Esteroides Gonadais/farmacologia , Humanos , Trabalho de Parto/metabolismo , Miométrio/metabolismo , Gravidez , Receptores de Ocitocina/efeitos dos fármacos , Regulação para Cima
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