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1.
Med J Malaysia ; 78(3): 350-356, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37271845

RESUMO

INTRODUCTION: In managing hypertension, monotherapy and sometimes a combination of more than one agent are used to achieve blood pressure (BP) control. The objective of this prospective, observational, multi-centre study was to assess the level of BP control in patients receiving one or more anti-hypertensive drugs in private medical centres in Malaysia according to the treatment regimens (monotherapy, free drug combinations and single pill combinations). MATERIALS AND METHODS: Data were collected through medical records and interview sessions with patients on current pharmacotherapy for hypertension management at baseline and 2-3 months later. Results are expressed as mean ± SD for continuous data and as frequencies and percentages for categorical data. RESULTS: Among 182 recruited patients, 89 (49%) achieved BP control by the end of the study. Majority (62/89) patients were on single-pill (monotherapy or SPC) antihypertensives. Majority (63/89) required more than two antihypertensives to achieve BP control. CONCLUSION: Both SPC and free drug combination antihypertensives reduced BPs, but physicians preferred SPC to improve BP control and increase treatment compliance.


Assuntos
Anti-Hipertensivos , Hipertensão , Humanos , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/efeitos adversos , Estudos Prospectivos , Malásia , Hipertensão/tratamento farmacológico , Pressão Sanguínea , Combinação de Medicamentos , Hospitais Privados
2.
J Neurosci ; 41(32): 6850-6863, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34210780

RESUMO

Sonic hedgehog (Shh) signaling from the primary cilium drives cerebellar granule cell precursor (GCP) proliferation. Mutations of hedgehog (Hh) pathway repressors commonly cause medulloblastoma, the most prevalent and malignant childhood brain tumor that arises from aberrant GCP proliferation. We demonstrate that Nestin Cre-driven conditional knock-out (CKO) of a Shh pathway repressor-Rab23 in the mouse brain of both genders caused mis-patterning of cerebellar folia and elevated GCP proliferation during early development, but with no prevalent occurrence of medulloblastoma at adult stage. Strikingly, Rab23-depleted GCPs exhibited upregulated basal level of Shh pathway activities despite showing an abnormal ciliogenesis of primary cilia. In line with the compromised ciliation, Rab23-depleted GCPs were desensitized against Hh pathway activity stimulations by Shh ligand and Smoothened (Smo) agonist-SAG, and exhibited attenuated stimulation of Smo-localization on the primary cilium in response to SAG. These results implicate multidimensional actions of Rab23 on Hh signaling cascade. Rab23 represses the basal level of Shh signaling, while facilitating primary cilium-dependent extrinsic Shh signaling activation. Collectively, our findings unravel instrumental roles of Rab23 in GCP proliferation and ciliogenesis. Furthermore, Rab23's potentiation of Shh signaling pathway through the primary cilium and Smo suggests a potential new therapeutic strategy for Smo/primary cilium-driven medulloblastoma.SIGNIFICANCE STATEMENT Primary cilium and Sonic hedgehog (Shh) signaling are known to regulate granule cell precursor (GCP) proliferation. Aberrant overactivation of Shh signaling pathway ectopically increases GCP proliferation and causes malignant childhood tumor called medulloblastoma. However, the genetic and molecular regulatory cascade of GCP tumorigenesis remains incompletely understood. Our finding uncovers Rab23 as a novel regulator of hedgehog (Hh) signaling pathway activity and cell proliferation in GCP. Intriguingly, we demonstrated that Rab23 confers dual functions in regulating Shh signaling; it potentiates primary cilium and Shh/Smoothened (Smo)-dependent signaling activation, while antagonizes basal level Hh activity. Our data present a previously underappreciated aspect of Rab23 in mediating extrinsic Shh signaling upstream of Smo. This study sheds new light on the mechanistic insights underpinning Shh signaling-mediated GCP proliferation and tumorigenesis.


Assuntos
Cerebelo/fisiologia , Cílios/metabolismo , Proteínas Hedgehog/metabolismo , Células-Tronco Neurais/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Proliferação de Células/fisiologia , Feminino , Masculino , Camundongos , Transdução de Sinais/fisiologia
4.
J Hosp Infect ; 122: 84-95, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35045340

RESUMO

BACKGROUND: Sepsis is an important global healthcare problem that is a key challenge faced by healthcare professionals face worldwide. One key effort aimed at reducing the global burden of sepsis is educating healthcare professionals about early identification and management of sepsis. AIM: To provide a comprehensive evaluation of sepsis education among healthcare professionals and students. METHODS: Six databases (PubMed, CINAHL, Embase, MEDLINE, Cochrane Central Register of Controlled Trials, and Scopus) were searched. We included studies that described and evaluated any form of education or training on sepsis delivered to healthcare professionals and students. Study outcomes were summarized according to the adapted Kirkpatrick model of training evaluation. RESULTS: Thirty-two studies were included in the review. The learning contents were reported to be in accordance with the Surviving Sepsis Campaign guidelines. Seven studies included the topic of interprofessional teamwork and communication in their sepsis education content. Most educational programmes were effective and reported positive effects on immediate knowledge outcomes. Interventions that were delivered through an active learning approach such as simulation and game-based learning generally produced greater gains than didactic teaching. Improvements in patient care processes and patient outcomes were associated with the concomitant existence or implementation of a hospital sepsis care bundle. CONCLUSION: Incorporating active learning strategies into sepsis education interventions has the potential to improve learners' long-term outcomes. In addition, sepsis education and a protocol-based sepsis care bundle act in synergy to augment greater improvements in care processes and patient benefits.


Assuntos
Pessoal de Saúde , Sepse , Competência Clínica , Atenção à Saúde , Pessoal de Saúde/educação , Humanos , Sepse/diagnóstico , Sepse/terapia , Estudantes
5.
Cell Signal ; 13(9): 599-616, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11495718

RESUMO

Rapid progress has been made recently in the definition of growth hormone (GH) receptor signal transduction pathways. It is now apparent that many cytokines, including GH, share identical or similar signalling components to exert their cellular effects. This review provides a brief discourse on the signal transduction pathways, which have been demonstrated to be utilized by GH. The identification of such pathways provides a basis for understanding the pleiotropic actions of GH. The mechanisms by which the specific cellular effects of GH are achieved remain to be elucidated.


Assuntos
Receptores da Somatotropina/metabolismo , Transdução de Sinais , Animais , Sinalização do Cálcio , Humanos , Substâncias Macromoleculares , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteína Quinase C/metabolismo , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/metabolismo , Receptores da Somatotropina/química , Fatores de Transcrição/metabolismo , Fosfolipases Tipo C/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-26736268

RESUMO

The need for a blood-brain barrier (BBB) model that accurately mimics the physiological characteristics of the in-vivo situation is well-recognized by researchers in academia and industry. However, there is currently no in-vitro model allowing studies of neuronal growth and/or function influenced by factors from the blood that cross through the BBB. Therefore, we established a 3D triple co-culture microfluidic system using human umbilical vein endothelial cells (HUVEC) together with primary rat astrocytes and neurons. Immunostaining confirmed the successful triple co-culture system consisting of an intact BBB with tight intercellular junctions in the endothelial monolayer. The BBB selective permeability was determined by a fluorescent-based assay using dextrans of different molecular weights. Finally, neuron functionality was demonstrated by calcium imaging.


Assuntos
Barreira Hematoencefálica , Técnicas de Cocultura/instrumentação , Técnicas de Cocultura/métodos , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Transporte Biológico , Barreira Hematoencefálica/efeitos dos fármacos , Dextranos/química , Dextranos/farmacocinética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Dispositivos Lab-On-A-Chip , Peso Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Permeabilidade , Ratos Long-Evans
7.
Endocrinology ; 139(10): 4364-72, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9751520

RESUMO

We have investigated the effect of GH on microtubular physiology in Chinese hamster ovary (CHO) cells stably transfected with the complementary DNA for the rat GH receptor (CHO-GHR(1-638)). We show here that after 30 min of human GH (hGH) treatment of CHO-GHR(1-638) cells, there was a significant increase in the level of polymerization of all four tubulin isoforms (alpha-, beta-, gamma-, and tyrosinated alpha-tubulin) compared with the serum-deprived state. However, this transient increase in the levels of polymerized tubulin after hGH treatment was particularly pronounced for beta- and tyr alpha-tubulin. For alpha- and gamma-tubulin, the hGH-induced increase in polymerization state lasted to approximately 3 h and then declined by 7 h, whereas for beta- and tyr alpha-tubulin there was a decrease in the polymerization state at 1-2 h after hGH treatment compared with the level at 30 min (but still greater than the serum-deprived state) followed by a second but lesser wave of increased polymerization lasting to 7 h. The changes in the polymerization state of the tubulins were not accompanied by comparative changes in the level of total cellular tubulin. The proline rich box 1 region of the GH receptor was required for hGH to stimulate tubulin polymerization indicative that this event is JAK dependent. Increased tubulin polymerization still occurred in response to hGH in a receptor truncation lacking the carboxyl terminal half of the intracellular domain of the GH receptor indicative that hGH induced changes in intracellular calcium concentration is not required for tubulin polymerization. Prior treatment of CHO-GHR(1-638) cells with hGH retarded colchicine induced microtubule depolymerization and also prevented colchicine induced apoptotic cell death. The integrity of the microtubule network was not required for GH-induced STAT5 mediated transcription as treatment of cells with colchicine, vincristine, or vinblastine did not alter the fold stimulation of the STAT5 mediated transcriptional response to GH. Thus one consequence of cellular treatment with GH is alteration in microtubule physiology.


Assuntos
Apoptose/efeitos dos fármacos , Colchicina/farmacologia , Hormônio do Crescimento Humano/farmacologia , Microtúbulos/efeitos dos fármacos , Proteínas do Leite , Tubulina (Proteína)/metabolismo , Animais , Células CHO , Cricetinae , Proteínas de Ligação a DNA/fisiologia , Humanos , Polímeros/metabolismo , Ratos , Receptores da Somatotropina/fisiologia , Fator de Transcrição STAT5 , Estaurosporina/farmacologia , Transativadores/fisiologia , Transcrição Gênica
8.
Endocrinology ; 138(8): 3207-15, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9231769

RESUMO

We have investigated the effect of GH on the organization of the actin cytoskeleton within the cell. Human GH (hGH) treatment (50 nM) of Chinese hamster ovary (CHO) cells stably transfected with the complementary DNA for the rat GH receptor (CHO-GHR(1-638)) resulted in a reorganization of actin filaments in the cell that was not observed upon GH treatment of the untransfected parental CHO cell line. hGH initially induced depolymerization of actin stress fibers similar in magnitude to that induced by treatment of the cells with 100 nM human insulin-like growth factor I. This loss of stress fibers was observed as early as 30 sec after addition of hGH to the medium, and maximal depolymerization of stress fibers was observed between 1-4 min after addition of hGH. This was followed by a slow, but submaximal, repolymerization of the stress fibers and the formation of localized focal filamentous actin containing complexes. Similar cytoskeletal changes were observed after hGH treatment in Swiss 3T3 fibroblasts and BRL cells stably transfected with rat GH receptor complementary DNA (BRL-GHR(1-6381)). Pretreatment of CHO-GHR(1-638) cells with wortmannin (a phosphatidylinositol 3-kinase inhibitor) and verapamil (a calcium channel antagonist) both inhibited the hGH-induced actin reorganization. The integrity of the actin cytoskeleton was not required for GH-induced STAT5 (signal transducer and activator of transcription-5)-mediated transcription, as treatment of cells with cytochalasins B and D did not alter the fold stimulation of the STAT5-mediated transcriptional response to GH. We conclude that GH induces a rapid reorganization of the actin cytoskeleton by a process requiring phosphatidylinositol 3-kinase activation and calcium influx, but this cytoskeletal reorganization is not required for the STAT5-mediated transcriptional response to GH.


Assuntos
Actinas/fisiologia , Citoesqueleto/fisiologia , Proteínas de Ligação a DNA/fisiologia , Hormônio do Crescimento/farmacologia , Proteínas do Leite , Transdução de Sinais/fisiologia , Transativadores/fisiologia , Transcrição Gênica/fisiologia , Células 3T3 , Citoesqueleto de Actina/fisiologia , Actinas/análise , Actinas/efeitos dos fármacos , Androstadienos/farmacologia , Animais , Células CHO , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular , Cricetinae , Citoesqueleto/química , Citoesqueleto/efeitos dos fármacos , DNA Complementar/análise , DNA Complementar/genética , Feminino , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Microscopia Eletrônica , Fosfatidilinositol 3-Quinases , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ratos , Receptores da Somatotropina/genética , Fator de Transcrição STAT5 , Fatores de Tempo , Transfecção , Verapamil/farmacologia , Wortmanina
9.
Growth Horm IGF Res ; 10 Suppl B: S51-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10984254

RESUMO

The growth hormone (GH) receptor and binding protein are synthesized in the CNS and are regulated differentially to their hepatic counterparts. GH is also synthesized in the CNS and is regulated differentially to its hypophyseal counterpart. Insulin-like growth factor I (IGF-I) is synthesized in the CNS and in the early postnatal period is regulated by peripherally secreted GH. Both GH and IGF-I alter the size and morphology of the CNS during development and affect differentiated cell function in the CNS, with consequent modulation of cognitive function. Differential utilization of the same signal transduction molecules indicates that GH and IGF-I possess distinct overlapping roles in CNS function.


Assuntos
Sistema Nervoso Central/metabolismo , Hormônio do Crescimento/biossíntese , Hormônio do Crescimento/fisiologia , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/fisiologia , Animais , Barreira Hematoencefálica , Humanos , Modelos Biológicos , RNA Mensageiro/metabolismo , Receptores da Somatotropina/biossíntese , Receptores da Somatotropina/fisiologia , Transdução de Sinais
10.
J Biol Chem ; 273(17): 10682-9, 1998 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9553131

RESUMO

We have demonstrated that growth hormone (GH) activates focal adhesion kinase (FAK), and this activation results in the tyrosine phosphorylation of two FAK substrates, paxillin and tensin. The activation of FAK is time-dependent (maximal activation at 5-15 min) and dose-dependent (maximal activation at 0.05 nM). FAK and paxillin are constitutively associated in the unstimulated state, remain associated during the stimulation phase, and recruit tyrosine-phosphorylated tensin to the complex after GH stimulation. Half of the carboxyl-terminal region of the GH receptor is dispensable for FAK activation, but FAK activation does require the proline-rich box 1 region of the GH receptor, indicative that FAK is downstream of JAK2. FAK associates with JAK2 but not JAK1 after GH stimulation of cells. Using FAK-replete and FAK-deficient cells, we also show that FAK is not required for STAT-mediated transcriptional activation by GH. The use of FAK in the signal transduction pathway utilized by GH may be central to many of the pleiotropic effects of GH, including cytoskeletal reorganization, cell migration, chemotaxis, mitogenesis, and/or prevention of apoptosis and gene transcription.


Assuntos
Moléculas de Adesão Celular/metabolismo , Proteínas do Leite , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Tirosina/metabolismo , Animais , Células CHO , Cricetinae , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Janus Quinase 2 , Paxilina , Fosfoproteínas/metabolismo , Fosforilação , Ligação Proteica , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT5 , Transativadores/metabolismo , Ativação Transcricional
11.
J Biol Chem ; 273(50): 33864-75, 1998 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-9837978

RESUMO

We have demonstrated previously that growth hormone (GH) activates focal adhesion kinase (FAK), and this activation results in the tyrosine phosphorylation of two FAK substrates, namely paxillin and tensin. We now show here in Chinese hamster ovary cells stably transfected with rat GH receptor cDNA that human (h)GH induces the formation of a large multiprotein signaling complex centered around another FAK-associated protein, p130(Cas) and the adaptor protein CrkII. hGH stimulates the tyrosine phosphorylation of both p130(Cas) and CrkII, their association, and the association of multiple other tyrosine-phosphorylated proteins to the complex. Both the c-Src and c-Fyn tyrosine kinases are tyrosine phosphorylated and activated by cellular hGH stimulation and form part of the multiprotein signaling complex as does tensin, paxillin, IRS-1, the p85 subunit of phosphatidylinositol 3-kinase, C3G, SHC, Grb-2, and Sos-1. c-Cbl and Nck are also tyrosine-phosphorylated by cellular stimulation with hGH and associate with the p130(Cas)-CrkII complex. c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) is activated in response to hGH in accordance with the formation of the abovementioned signaling complex, and hGH stimulated JNK/SAPK activity is increased in CrkII overexpressing NIH3T3 cells compared with vector transfected NIH3T3 cells. The formation of such a large multiprotein signaling complex by GH, with the resultant activation of multiple downstream effector molecules, may be central to many of the pleiotropic effects of GH.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Hormônio do Crescimento/farmacologia , Proteínas Quinases Ativadas por Mitógeno , Fosfoproteínas/metabolismo , Proteínas Quinases/metabolismo , Proteínas , Transdução de Sinais , Células 3T3 , Animais , Células CHO , Cricetinae , Proteína Substrato Associada a Crk , Proteínas do Citoesqueleto/metabolismo , Ativação Enzimática , Humanos , Proteínas Substratos do Receptor de Insulina , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Proteínas dos Microfilamentos/metabolismo , Paxilina , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-crk , Proteínas Proto-Oncogênicas c-fyn , Ratos , Proteínas Recombinantes/farmacologia , Proteína p130 Retinoblastoma-Like , Tensinas , Tirosina/metabolismo
12.
J Biol Chem ; 275(23): 17683-92, 2000 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-10748058

RESUMO

We have examined the role of CrkII in the cellular response to both human growth hormone (hGH) and human insulin-like growth factor-1 (hIGF-1). We have demonstrated that overexpression of the adaptor molecule enhances both basal phosphatidylinositol 3-kinase (PI 3-kinase) activity and also dramatically enhances the ability of both hormones to stimulate PI 3-kinase activity in the cell. Many of the effects of CrkII overexpression on hGH- and hIGF-1-stimulated cellular function can then be attributed to CrkII enhancement of PI 3-kinase stimulation by these hormones. Thus, CrkII-enhanced PI 3-kinase activity is used to enhance actin filament reorganization in response to both hGH and hIGF-1, to enhance stress activated protein kinase (SAPK) activity in response to hGH, and to diminish STAT5-mediated transcription in response to hGH. It is apparent, however, that CrkII also regulates cellular function independent of its ability to stimulate PI 3-kinase activity. This is evidenced by the ability of CrkII, in a PI 3-kinase-independent manner, to diminish the activation of p44/42 mitogen-activated protein kinase in response to both hGH and hIGF-1 and to inhibit the activation of SAPK by hIGF-1. Therefore, despite the common use of CrkII to activate PI 3-kinase, CrkII also allows hGH or hIGF-1 to selectively switch the activation of SAPK. Thus, common utilization of CrkII by hGH and hIGF-1 allows the execution of common cellular effects of these hormones, concomitant with the retention of hormonal specificity.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas , Células 3T3 , Animais , Humanos , Cinética , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases/genética , Proteínas Proto-Oncogênicas c-crk , Proteínas Recombinantes/metabolismo , Transfecção , Domínios de Homologia de src
13.
J Biol Chem ; 276(24): 21464-75, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11297545

RESUMO

By use of cDNA array technology we have screened 588 genes to determine the effect of autocrine production of human growth hormone (hGH) on gene expression in human mammary carcinoma cells. We have used a previously described cellular model to study autocrine hGH function in which the hGH gene or a translation-deficient hGH gene was stably transfected into MCF-7 cells. Fifty two of the screened genes were regulated, either positively () or negatively (), by autocrine production of hGH. We have now characterized the role of one of the up-regulated genes, chop (gadd153), in the effect of autocrine production of hGH on mammary carcinoma cell number. The effect of autocrine production of hGH on the level of CHOP mRNA was exerted at the transcriptional level as autocrine hGH increased chloramphenicol acetyltransferase production from a reporter plasmid containing a 1-kilobase pair fragment of the chop promoter. The autocrine hGH-stimulated increase in CHOP mRNA also resulted in an increase in CHOP protein. As a consequence, autocrine hGH stimulation of CHOP-mediated transcriptional activation was increased. Stable transfection of human CHOP cDNA into mammary carcinoma cells demonstrated that CHOP functioned not as a mediator of hGH-stimulated mitogenesis but rather enhanced the protection from apoptosis afforded by hGH in a p38 MAPK-dependent manner. Thus transcriptional up-regulation of chop is one mechanism by which hGH regulates mammary carcinoma cell number.


Assuntos
Neoplasias da Mama/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Sobrevivência Celular/fisiologia , Regulação Neoplásica da Expressão Gênica , Hormônio do Crescimento Humano/fisiologia , Fatores de Transcrição/metabolismo , Neoplasias da Mama/patologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Sobrevivência Celular/efeitos dos fármacos , Clonagem Molecular , Dano ao DNA , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Biblioteca Gênica , Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/farmacologia , Humanos , Proteínas de Neoplasias/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição CHOP , Fatores de Transcrição/genética , Transcrição Gênica , Ativação Transcricional , Transfecção , Células Tumorais Cultivadas
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