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1.
J Emerg Med ; 54(5): 665-673, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29573904

RESUMO

BACKGROUND: Emergency department (ED) overcrowding is a serious issue worldwide. OBJECTIVES: This study was done to evaluate the degree of overcrowding in local "teaching hospitals" in Beijing, and to ascertain the apparent root causes for the pervasive degree of overcrowding in these EDs. METHODS: This is a multicenter cross-sectional study. The studied population included all ED patients from 18 metropolitan teaching hospital EDs in Beijing for calendar years 2013 and 2014. Patient characteristics, and the primary reasons that these patients sought care in these EDs, are described. RESULTS: The total numbers of annual emergency visits were 1,554,387 and 1,615,571 in 2013 and 2014, respectively. High acuity cases accounted for 4.6% and 5.5% of the total annual emergency visits in 2013 and 2014, respectively. The percentage of patients placed into "Observation" beds, which were created to accommodate patients deemed to have problems too complex to be treated in an inpatient bed, or to accommodate patients simply needing chronic care, was 11.9% and 13.1% in 2013 and 2014, respectively. The ED-boarded patients accounted for 2.71% and 2.6% of the total annual emergency visits in 2013 and 2014, respectively. The average waiting time to admit the ED-boarded patients was 37.1 h and 36.2 h in 2013 and 2014, respectively. Respiratory symptoms were the most common presenting complaints, and an upper respiratory infection was the most common ED diagnosis. Patients who had pneumonia or various manifestations of end-stage diseases, such as advanced dementia or multiple organ dysfunction, were the most common characteristics of patients who had stays in "Observation" units. CONCLUSIONS: One principal reason for ED crowding in Beijing lies in the large numbers of patients who persist in the expectation of receiving ongoing care in the ED for minor illnesses. However, as is true in many nations, one of the other most important root causes of ED crowding is "access block," the inability to promptly move patients deemed by emergency physicians to need inpatient care to an inpatient bed for that care. However, in our system, another challenge, not widely described as a contributor to crowding in other nations, is that doctors assigned to inpatient services have been empowered to refuse to admit patients perceived to have overly "complex" needs. Further, patients with multisystem illnesses or end-stage status, who need ongoing chronic care to manage activities of daily living, have begun to populate Beijing EDs in increasing numbers. This is an issue with various root causes.


Assuntos
Aglomeração , Serviço Hospitalar de Emergência/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Serviço Hospitalar de Emergência/organização & administração , Feminino , Acessibilidade aos Serviços de Saúde/normas , Hospitais de Ensino/organização & administração , Hospitais de Ensino/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
2.
Physiol Genomics ; 45(1): 47-57, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23170035

RESUMO

11ß-Hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is implicated in the etiology of metabolic syndrome. We previously showed that pharmacological inhibition of 11ß-HSD1 ameliorated multiple facets of metabolic syndrome and attenuated atherosclerosis in ApoE-/- mice. However, the molecular mechanism underlying the atheroprotective effect was not clear. In this study, we tested whether and how 11ß-HSD1 inhibition affects vascular inflammation, a major culprit for atherosclerosis and its associated complications. ApoE-/- mice were treated with an 11ß-HSD1 inhibitor for various periods of time. Plasma lipids and aortic cholesterol accumulation were quantified. Several microarray studies were carried out to examine the effect of 11ß-HSD1 inhibition on gene expression in atherosclerotic tissues. Our data suggest 11ß-HSD1 inhibition can directly modulate atherosclerotic plaques and attenuate atherosclerosis independently of lipid lowering effects. We identified immune response genes as the category of mRNA most significantly suppressed by 11ß-HSD1 inhibition. This anti-inflammatory effect was further confirmed in plaque macrophages and smooth muscle cells procured by laser capture microdissection. These findings in the vascular wall were corroborated by reduction in circulating MCP1 levels after 11ß-HSD1 inhibition. Taken together, our data suggest 11ß-HSD1 inhibition regulates proinflammatory gene expression in atherosclerotic tissues of ApoE-/- mice, and this effect may contribute to the attenuation of atherosclerosis in these animals.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Aterosclerose/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Vasculite/tratamento farmacológico , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Apolipoproteínas E/genética , Aterosclerose/etiologia , Colesterol/metabolismo , Perfilação da Expressão Gênica , Genes MHC da Classe II/genética , Glucocorticoides/metabolismo , Microdissecção e Captura a Laser , Lipídeos/sangue , Camundongos , Camundongos Knockout , Análise em Microsséries , Vasculite/complicações
3.
Transgenic Res ; 21(3): 633-44, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22038448

RESUMO

Metabolic syndrome is a combination of medical disorders that increases the risk of developing cardiovascular disease and diabetes. Constitutive overexpression of 11ß-HSD1 in adipose tissue in mice leads to metabolic syndrome. In the process of generating transgenic mice overexpressing 11ß-HSD1 in an inducible manner, we found a metabolic syndrome phenotype in control, transgenic mice, expressing the reverse tetracycline-transactivator (rtTA) in adipose tissue. The control mice exhibited all four sequelae of metabolic syndrome (visceral obesity, insulin resistance, dyslipidemia, and hypertension), a pro-inflammatory state and marked hepatic steatosis. Gene expression profiling of the adipose tissue, muscle and liver of these mice revealed changes in expression of genes involved in lipid metabolism, insulin resistance, and inflammation. Transient transfection of rtTA, but not tTS, into 3T3-L1 cells resulted in lipid accumulation. We conclude that expression of rtTA in adipose tissue causes metabolic syndrome in mice.


Assuntos
Tecido Adiposo/metabolismo , Síndrome Metabólica/genética , Transativadores/metabolismo , Ativação Transcricional , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Células 3T3-L1 , Tecido Adiposo/patologia , Animais , Pressão Sanguínea , Cromossomos de Mamíferos/genética , Cromossomos de Mamíferos/metabolismo , Fragmentação do DNA , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Perfilação da Expressão Gênica , Resistência à Insulina , Metabolismo dos Lipídeos , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Camundongos , Camundongos Transgênicos , Músculos/metabolismo , Músculos/patologia , Fenótipo , Tetraciclina/metabolismo , Transativadores/genética , Transfecção , Transgenes
4.
Nat Med ; 11(12): 1293-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16273102

RESUMO

Pre-exposure oral prophylaxis with antiviral drugs is a potential method for preventing transmission of human immunodeficiency virus type 1 (HIV-1). We show that oral delivery of CMPD167, a small molecule that binds to the CCR5 coreceptor, for 10-14 d can protect a substantial proportion of macaques from vaginal infection with a CCR5-using virus (SHIV-162P3). The macaques that became infected despite receiving CMPD167 had reduced plasma viremia levels during the earliest stages of infection.


Assuntos
Antagonistas dos Receptores CCR5 , Macaca/virologia , Pirazóis/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vagina/virologia , Valina/análogos & derivados , Administração Oral , Animais , Feminino , Pirazóis/administração & dosagem , Fatores de Tempo , Vagina/efeitos dos fármacos , Valina/administração & dosagem , Valina/farmacologia , Carga Viral
5.
J Exp Med ; 202(4): 517-27, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16103409

RESUMO

The enzyme 11beta-hydroxysteroid dehydrogenase (HSD) type 1 converts inactive cortisone into active cortisol in cells, thereby raising the effective glucocorticoid (GC) tone above serum levels. We report that pharmacologic inhibition of 11beta-HSD1 has a therapeutic effect in mouse models of metabolic syndrome. Administration of a selective, potent 11beta-HSD1 inhibitor lowered body weight, insulin, fasting glucose, triglycerides, and cholesterol in diet-induced obese mice and lowered fasting glucose, insulin, glucagon, triglycerides, and free fatty acids, as well as improved glucose tolerance, in a mouse model of type 2 diabetes. Most importantly, inhibition of 11beta-HSD1 slowed plaque progression in a murine model of atherosclerosis, the key clinical sequela of metabolic syndrome. Mice with a targeted deletion of apolipoprotein E exhibited 84% less accumulation of aortic total cholesterol, as well as lower serum cholesterol and triglycerides, when treated with an 11beta-HSD1 inhibitor. These data provide the first evidence that pharmacologic inhibition of intracellular GC activation can effectively treat atherosclerosis, the key clinical consequence of metabolic syndrome, in addition to its salutary effect on multiple aspects of the metabolic syndrome itself.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Adamantano/análogos & derivados , Arteriosclerose/tratamento farmacológico , Azepinas/administração & dosagem , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Resistência à Insulina , Triazóis/administração & dosagem , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adamantano/administração & dosagem , Animais , Aorta/metabolismo , Arteriosclerose/complicações , Arteriosclerose/enzimologia , Glicemia/efeitos dos fármacos , Cortisona/metabolismo , Dieta Aterogênica , Modelos Animais de Doenças , Ácidos Graxos/sangue , Hidrocortisona , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Síndrome , Triglicerídeos/sangue
6.
Nature ; 438(7064): 99-102, 2005 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-16258536

RESUMO

Human immunodeficiency virus type 1 (HIV-1) continues to spread, principally by heterosexual sex, but no vaccine is available. Hence, alternative prevention methods are needed to supplement educational and behavioural-modification programmes. One such approach is a vaginal microbicide: the application of inhibitory compounds before intercourse. Here, we have evaluated the microbicide concept using the rhesus macaque 'high dose' vaginal transmission model with a CCR5-receptor-using simian-human immunodeficiency virus (SHIV-162P3) and three compounds that inhibit different stages of the virus-cell attachment and entry process. These compounds are BMS-378806, a small molecule that binds the viral gp120 glycoprotein and prevents its attachment to the CD4 and CCR5 receptors, CMPD167, a small molecule that binds to CCR5 to inhibit gp120 association, and C52L, a bacterially expressed peptide inhibitor of gp41-mediated fusion. In vitro, all three compounds inhibit infection of T cells and cervical tissue explants, and C52L acts synergistically with CMPD167 or BMS-378806 to inhibit infection of cell lines. In vivo, significant protection was achieved using each compound alone and in combinations. CMPD167 and BMS-378806 were protective even when applied 6 h before challenge.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/prevenção & controle , HIV/efeitos dos fármacos , Macaca mulatta/virologia , Fusão de Membrana/efeitos dos fármacos , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vagina/virologia , Administração Intravaginal , Animais , Fármacos Anti-HIV/administração & dosagem , Antagonistas dos Receptores CCR5 , Antígenos CD4/metabolismo , Fusão Celular , Quimioterapia Combinada , Feminino , HIV/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/transmissão , Infecções por HIV/virologia , Piperazinas/administração & dosagem , Piperazinas/farmacologia , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Receptores CCR5/metabolismo , Receptores Virais/antagonistas & inibidores , Receptores Virais/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/metabolismo , Fatores de Tempo , Vagina/efeitos dos fármacos , Valina/administração & dosagem , Valina/análogos & derivados , Valina/farmacologia
7.
J Exp Med ; 198(10): 1551-62, 2003 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-14623909

RESUMO

Human immunodeficiency virus type 1 (HIV-1) fuses with cells after sequential interactions between its envelope glycoproteins, CD4 and a coreceptor, usually CC chemokine receptor 5 (CCR5) or CXC receptor 4 (CXCR4). CMPD 167 is a CCR5-specific small molecule with potent antiviral activity in vitro. We show that CMPD 167 caused a rapid and substantial (4-200-fold) decrease in plasma viremia in six rhesus macaques chronically infected with simian immunodeficiency virus (SIV) strains SIVmac251 or SIVB670, but not in an animal infected with the X4 simian-human immunodeficiency virus (SHIV), SHIV-89.6P. In three of the SIV-infected animals, viremia reduction was sustained. In one, there was a rapid, but partial, rebound and in another, there was a rapid and complete rebound. There was a substantial delay (>21 d) between the end of therapy and the onset of full viremia rebound in two animals. We also evaluated whether vaginal administration of gel-formulated CMPD 167 could prevent vaginal transmission of the R5 virus, SHIV-162P4. Complete protection occurred in only 2 of 11 animals, but early viral replication was significantly less in the 11 CMPD 167-recipients than in 9 controls receiving carrier gel. These findings support the development of small molecule CCR5 inhibitors as antiviral therapies, and possibly as components of a topical microbicide to prevent HIV-1 sexual transmission.


Assuntos
Antirretrovirais/farmacologia , Antagonistas dos Receptores CCR5 , Macaca mulatta/virologia , Pirazóis/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Valina/farmacologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Síndrome de Imunodeficiência Adquirida dos Símios/terapia , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Valina/análogos & derivados
8.
Front Immunol ; 10: 644, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024528

RESUMO

Aspergillosis is difficult to treat and carries a high mortality rate in immunocompromised patients. Neutrophils play a critical role in control of infection but may be diminished in number and function during immunosuppressive therapies. Here, we measure the effect of three bifunctional small molecules that target Aspergillus fumigatus and prime neutrophils to generate a more effective response against the pathogen. The molecules combine two moieties joined by a chemical linker: a targeting moiety (TM) that binds to the surface of the microbial target, and an effector moiety (EM) that interacts with chemoattractant receptors on human neutrophils. We report that the bifunctional compounds enhance the interactions between primary human neutrophils and A. fumigatus in vitro, using three microfluidic assay platforms. The bifunctional compounds significantly enhance the recruitment of neutrophils, increase hyphae killing by neutrophils in a uniform concentration of drug, and decrease hyphal tip growth velocity in the presence of neutrophils compared to the antifungal targeting moiety alone. We validated that the bifunctional compounds are also effective in vivo, using a zebrafish infection model with neutrophils expressing the appropriate EM receptor. We measured significantly increased phagocytosis of A. fumigatus conidia by neutrophils expressing the EM receptor in the presence of the compounds compared to receptor-negative cells. Finally, we demonstrate that treatment with our lead compound significantly improved the antifungal activity of neutrophils from immunosuppressed patients ex vivo. This type of bifunctional compounds strategy may be utilized to redirect the immune system to destroy fungal, bacterial, and viral pathogens.


Assuntos
Aspergilose/tratamento farmacológico , Aspergillus fumigatus/imunologia , Sistemas de Liberação de Medicamentos , Neutrófilos/imunologia , Animais , Aspergilose/imunologia , Aspergilose/patologia , Humanos , Neutrófilos/patologia , Peixe-Zebra
9.
Org Lett ; 5(14): 2473-5, 2003 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-12841758

RESUMO

[reaction: see text] A novel approach to alpha,alpha-disubstituted-beta-amino acids (beta(2,2)-amino acids) was employed in the synthesis of a series of 3-(pyrrolidin-1-yl)propionic acids possessing high affinity for the CCR5 receptor and potent anti-HIV activity. The rat pharmacokinetics for these new analogues featured higher bioavailabilities and lower rates of clearance as compared to cyclopentane 1.


Assuntos
Fármacos Anti-HIV/farmacologia , Antagonistas dos Receptores CCR5 , Propionatos/farmacologia , Pirrolidinas/farmacologia , Fármacos Anti-HIV/farmacocinética , Disponibilidade Biológica , Propionatos/farmacocinética , Pirrolidinas/farmacocinética
10.
J Travel Med ; 9(3): 127-31, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12088577

RESUMO

BACKGROUND: There is little data available on the actual risk to travelers of being possibly exposed to rabies. This data would be useful in advising travelers who are considering rabies pre-exposure immunization. In addition, it is not known how many travelers are already pre-immunized when they are bitten by a possibly rabid animal. The current study was performed to determine the rate at which travelers to Nepal are possibly exposed to rabies, and to determine risk factors for possible rabies exposure. METHODS: A prospective 3-year study was carried out at the Canadian International Water and Energy Consultants (CIWEC) Clinic Travel Medicine Center in Kathmandu, Nepal, during the years 1996 through 1998. All non-Nepalese and non-Indian patients who presented with animal bites or scratches were eligible to be included in the study. RESULTS: Ninety-nine persons presented with possible rabies exposures to the CIWEC Clinic during the study period; 56 were tourists, and 43 were resident expatriates. The incidence of people presenting to the CIWEC clinic with possible rabies exposures was 1.9 per 1,000 persons/year for tourists, and 5.7 per 1,000 persons/year for resident expatriates (p <.0001). The incidence of possible exposure to rabies while trekking was 1.2 per 1,000 persons/year. Women were significantly more likely than men to present with a possible rabies exposure, accounting for 61% of patients (p =.0027). Younger people were more likely to have bite exposures to the face and head than older patients. The length of time between exposure and treatment averaged 1.6 to 5.0 days. Among patients presenting with animal bites, 56% of foreign residents, and 21% of tourists had been pre-immunized against rabies. CONCLUSIONS: Foreign residents of Nepal are significantly more likely to be exposed to rabies than tourists. Trekking does not increase the chances of being exposed to rabies. Children have a higher risk of being bitten on the face and head, and females are more likely than males to be bitten or scratched by a possibly rabid animal.


Assuntos
Mordeduras e Picadas/epidemiologia , Emigração e Imigração/estatística & dados numéricos , Raiva/epidemiologia , Viagem/estatística & dados numéricos , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Comorbidade , Cães , Feminino , Haplorrinos , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Nepal/epidemiologia , Raiva/prevenção & controle , Raiva/transmissão , Vacina Antirrábica , Medição de Risco , Vacinação/estatística & dados numéricos , Zoonoses
11.
BMJ Case Rep ; 20142014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25150246

RESUMO

This is the remarkable story of survival against all the odds. A passenger had a myocardial infarction complicated by a witnessed cardiac arrest while on a commercial flight through some of the most remote airspace on the planet. Immediate cardiopulmonary resuscitation and use of an automatic external defibrillator achieved rapid return of spontaneous circulation. Passengers and crew worked effectively together, under the guidance of a physician, to provide critical care to the patient while the flight diverted so he could be transferred to an emergency hospital in Beijing for eventual thrombolysis and postresuscitation care. He made a rapid and full recovery to be discharged from hospital, neurologically intact, 10 days later.


Assuntos
Reanimação Cardiopulmonar/métodos , Infarto do Miocárdio/complicações , Parada Cardíaca Extra-Hospitalar/etiologia , Idoso , Aeronaves , Humanos , Masculino , Infarto do Miocárdio/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Fatores de Tempo
12.
J Travel Med ; 18(2): 102-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21366793

RESUMO

BACKGROUND: Diarrhea is the most common illness among travelers and expatriates in Nepal. Published data on the etiology of travelers' diarrhea (TD) in Nepal are over 13 years old and no prior data exist on antibiotic susceptibility for currently used drugs. We investigated the etiology of diarrhea and antimicrobial susceptibility pattern of bacterial pathogens and compared the results to previous work from the same clinical setting. METHODS: A total of 381 cases and 176 controls were enrolled between March 2001 and 2003 in a case-control study. Enrollees were over age 18 years from high socioeconomic countries visiting or living in Nepal. Stool samples were assessed by microbiologic, molecular identification, and enzyme immunoassay (EIA) methods, and antimicrobial susceptibility was determined by disk diffusion. Risk factors were assessed by questionnaires. RESULTS: At least one enteropathogen was identified in 263 of 381 (69%) cases and 47 of 176 (27%) controls (p ≤ 0.001). Pathogens significantly detected among cases were Campylobacter (17%), enterotoxigenic Escherichia coli (ETEC) (15%), Shigella (13%), and Giardia (11%). Cyclospora was detected only in cases (8%) mainly during monsoon season. Although 71% of Campylobacter isolates were resistant to ciprofloxacin, 80% of bacterial isolates overall were sensitive to either ciprofloxacin or azithromycin while 20% were intermediately sensitive or resistant. No bacterial isolates were resistant to both drugs. CONCLUSIONS: The most common pathogens causing TD in Nepal were Campylobacter, ETEC, and Shigella. Because resistance to fluoroquinolone or azithromycin was similar, one of these drugs could be used as empiric therapy for TD with the other reserved for treatment failures.


Assuntos
Diarreia/diagnóstico , Diarreia/tratamento farmacológico , Resistência Microbiana a Medicamentos , Bactérias Gram-Negativas/patogenicidade , Viagem , Adulto , Antibacterianos/uso terapêutico , Campylobacter/patogenicidade , Estudos de Casos e Controles , Cyclospora/patogenicidade , Países Desenvolvidos , Escherichia coli Enterotoxigênica/patogenicidade , Feminino , Giardia/patogenicidade , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Nepal , Shigella/patogenicidade , Adulto Jovem
13.
J Virol ; 81(2): 532-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16943294

RESUMO

The coexpression of human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins and receptors leads to the lysis of single cells by a process that is dependent upon membrane fusion. This cell lysis was inhibited by low-molecular-weight compounds that interfere with receptor binding or with receptor-induced conformational transitions in the envelope glycoproteins. A peptide, T20, potently inhibited cell-cell fusion but had no effect on single cell lysis mediated by the HIV-1 envelope glycoproteins. Thus, critical events in the lysis of single cells by the HIV-1 envelope glycoproteins occur in intracellular compartments accessible only to small inhibitory compounds.


Assuntos
Éteres/farmacologia , Produtos do Gene env/metabolismo , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Hidrocarbonetos Fluorados/farmacologia , Fusão de Membrana/efeitos dos fármacos , Piperazinas/farmacologia , Animais , Linhagem Celular , Efeito Citopatogênico Viral/efeitos dos fármacos , Cães , Enfuvirtida , Proteína gp41 do Envelope de HIV/farmacologia , Humanos , Peso Molecular , Fragmentos de Peptídeos/farmacologia
14.
Bioorg Med Chem Lett ; 17(2): 309-14, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17092717

RESUMO

A series of racemic and homochiral alpha-aminothiazole-gamma-aminobutyroamides that display high affinities for human and murine CCR2 and functional antagonism by inhibition of monocyte recruitment are described. A representative example is (2S)-2-[2-(acetylamino)-1,3-thiazol-4-yl]-N-[3-methyl-5-(trifluoromethyl)benzyl]-4-(4-phenylpiperidin-1-yl)butanamide, which shows 5 nM affinity for human monocytes and CHO cells expressing the human CCR2b receptor. It also inhibited MCP-1 initiated chemotaxis of human monocytes with an IC50 of 0.69 nM.


Assuntos
Receptores de Quimiocinas/antagonistas & inibidores , Animais , Células CHO , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/metabolismo , Quimiotaxia/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cricetinae , Cricetulus , Cães , Desenho de Fármacos , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Membranas/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Antagonistas dos Receptores de Neurocinina-1 , Ratos , Ratos Sprague-Dawley , Receptores CCR2 , Receptores de Quimiocinas/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
15.
J Immunol ; 179(4): 2289-99, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17675490

RESUMO

Pharmacologic antagonism of CCR5, a chemokine receptor expressed on macrophages and activated T cells, is an effective antiviral therapy in patients with macrophage-tropic HIV infection, but its efficacy in modulating inflammation and immunity is only just beginning to be investigated. In this regard, the recruitment of CCR5-bearing cells into clinical allografts is a hallmark of acute rejection and may anticipate chronic rejection, whereas conventionally immunosuppressed renal transplant patients homozygous for a nonfunctional Delta32 CCR5 receptor rarely exhibit late graft loss. Therefore, we explored the effects of a potent, highly selective CCR5 antagonist, Merck's compound 167 (CMPD 167), in an established cynomolgus monkey cardiac allograft model. Although perioperative stress responses (fever, diminished activity) and the recruitment of CCR5-bearing leukocytes into the graft were markedly attenuated, anti-CCR5 monotherapy only marginally prolonged allograft survival. In contrast, relative to cyclosporine A monotherapy, CMPD 167 with cyclosporine A delayed alloantibody production, suppressed cardiac allograft vasculopathy, and tended to further prolong graft survival. CCR5 therefore represents an attractive therapeutic target for attenuating postsurgical stress responses and favorably modulating pathogenic alloimmunity in primates, including man.


Assuntos
Antagonistas dos Receptores CCR5 , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração/imunologia , Macrófagos/imunologia , Pirazóis/administração & dosagem , Linfócitos T/imunologia , Tolerância ao Transplante/efeitos dos fármacos , Valina/análogos & derivados , Animais , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Autoimunidade/efeitos dos fármacos , Autoimunidade/imunologia , Ciclosporina/administração & dosagem , Modelos Animais de Doenças , Sobrevivência de Enxerto/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/patologia , Transplante de Coração/patologia , Humanos , Imunossupressores/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Isoanticorpos/imunologia , Transplante de Rim/imunologia , Macaca fascicularis , Macrófagos/patologia , Masculino , Estresse Fisiológico/tratamento farmacológico , Estresse Fisiológico/imunologia , Estresse Fisiológico/patologia , Linfócitos T/patologia , Tolerância ao Transplante/imunologia , Transplante Homólogo , Valina/administração & dosagem , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/imunologia , Doenças Vasculares/patologia
16.
Bioorg Med Chem Lett ; 15(4): 977-82, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15686896

RESUMO

Synthesis of analogs containing more rigid bicyclic piperidine replacements for the 4-benzyloxycarbonyl-(ethyl)amino-piperidine moiety of the CCR5 antagonist structure, 1, is described. Although similar binding affinity to the lead was achieved with some analogs they were overall less potent anti-HIV agents suggesting that other features besides CCR5 binding are required for good anti-viral activity.


Assuntos
Fármacos Anti-HIV/síntese química , Antagonistas dos Receptores CCR5 , Sulfonas/síntese química , Fármacos Anti-HIV/farmacologia , Butanos/síntese química , Butanos/farmacologia , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Piperidinas/síntese química , Piperidinas/farmacologia , Relação Estrutura-Atividade , Sulfonas/farmacologia , Vírus/efeitos dos fármacos
18.
Cell Immunol ; 223(1): 1-12, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12914753

RESUMO

CXCR6, the receptor for the membrane-anchored chemokine, CXCL16, is expressed on a subset of CCR5-bearing memory T cells, and may play a role in recruiting these cells to sites of inflammation. Here, we set out to determine the effect of T cell activation on CXCR6 expression. Highly purified human peripheral blood T cells were cultured for 7-8 days in presence of IL-2 (400 U/ml) to enhance CXCR6 expression. Overnight stimulation with anti-CD3 mAb+anti-CD28 mAb, which resulted in CD69 induction and cytokine (IL-2 and IFN-gamma) production, reduced cell surface expression of CXCR6 by 85% and that of CCR5 by 76%. The Ca(2+) ionophore, ionomycin (125-500 ng/ml), also markedly diminished CXCR6 expression (85%), but without inducing CD69 expression or cytokine production, and reduced CCR5 expression by only 40%. In contrast, the phorbol esters, PdBu or PMA had little effect on CXCR6 expression (23% reduction) but induced CD69 expression and caused a profound down-regulation (92%) of CCR5 expression. Moreover, CCR7, whose expression was low on CXCR6(+) T cells, was little affected by any of these modes of activation. The down-regulation of CXCR6 expression induced by CD3/CD28 activation was blocked by the broad kinase inhibitor, staurosporine, and by the src kinase inhibitor, PP2, but not by the MEK1 inhibitor, U0106. Most interestingly, the calcineurin inhibitor, FK506, consistently inhibited CD3/CD28-induced CXCR6 down-regulation. FK506 also blocked the decrease of CXCR6 expression caused by ionomycin, whereas staurosporine or PP2 had no effect on this decrease. Altogether, these data indicate that CXCR6 expression is down-regulated, independent of CCR5 or CD69 expression and of cytokine induction, by T cell activation signals that involve predominantly the Ca(2+)-dependent calcineurin pathway.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Calcineurina/imunologia , Ativação Linfocitária/imunologia , Receptores de Citocinas/biossíntese , Receptores Acoplados a Proteínas G , Receptores Virais , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Butadienos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Citocinas/imunologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Citometria de Fluxo , Humanos , Imunossupressores , Interleucina-2/imunologia , Lectinas Tipo C , Nitrilas/farmacologia , Pirimidinas/farmacologia , Receptores CCR7 , Receptores CXCR6 , Receptores de Quimiocinas/imunologia , Receptores de Quimiocinas/metabolismo , Receptores de Citocinas/genética , Receptores de Citocinas/imunologia , Receptores de Citocinas/metabolismo , Transdução de Sinais/imunologia , Estaurosporina/farmacologia , Tacrolimo/farmacologia
19.
Virology ; 328(1): 19-29, 2004 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-15380354

RESUMO

Human immunodeficiency virus type 1 (HIV-1) fusion with its target cells is initiated by sequential interactions between its envelope glycoprotein, CD4, and a co-receptor, usually CCR5 or CXCR4. Small molecules that bind to CCR5 and prevent its use by R5 HIV-1 strains are now being developed clinically as antiviral drugs. To test whether a block to CCR5 promotes the replication of viruses that enter cells via CXCR4 and are associated with accelerated disease progression, we administered a small molecule CCR5 inhibitor, CMPD 167, to three macaques dual-infected with both R5 (SIVmac251) and X4 (SHIV-89.6P) viruses. CMPD 167 caused a rapid and substantial (on average, 50-fold) suppression of R5 virus replication in each animal. In two of the animals, but not in the third, a rapid, transient, 8- to 15-fold increase in the amount of plasma X4 virus occurred. In neither animal was the increase in X4 viral load sustained throughout therapy, however. These observations may have relevance for the development of CCR5 inhibitors for treatment of HIV-1 infection of humans.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Antagonistas dos Receptores CCR5 , Infecções por HIV/tratamento farmacológico , HIV-1 , Pirazóis/uso terapêutico , Vírus Reordenados , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia , Valina/uso terapêutico , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Infecções por HIV/virologia , HIV-1/fisiologia , Macaca mulatta , Vírus Reordenados/fisiologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/patogenicidade , Valina/análogos & derivados , Carga Viral , Replicação Viral/efeitos dos fármacos
20.
J Biol Chem ; 277(37): 33799-810, 2002 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-12101185

RESUMO

Eosinophils are major effector cells implicated in a number of chronic inflammatory diseases in humans, particularly bronchial asthma and allergic rhinitis. The beta-chemokine receptor C-C chemokine receptor 3 (CCR3) provides a mechanism for the selective recruitment of eosinophils into tissue and thus has recently become an attractive biological target for therapeutic intervention. In order to develop in vivo models of inflammatory diseases, it is essential to identify and characterize the homologues of human eotaxin (C-C chemokine ligand 11) and CCR3 from other species, such as non-human primates. Accordingly, we cloned the macaque eotaxin and CCR3 genes and revealed that they were 91 and 92% identical at the amino acid level to their human homologues, respectively. Macaque CCR3 expressed in the murine pre-B L1-2 cell line bound macaque eotaxin with high affinity (K(d) = 0.1 nm) and exhibited a robust eotaxin-induced Ca(2+) flux and chemotaxis. Characterization of beta-chemokines on native macaque CCR3 on eosinophils was performed by means of eotaxin-induced shape change in whole blood using a novel signaling assay known as gated autofluorescence forward scatter. Additionally, mAbs were raised against macaque CCR3 using two different immunogens: a 30-amino acid synthetic peptide derived from the predicted NH(2) terminus of macaque CCR3 and intact macaque CCR3-transfected cells. These anti-macaque CCR3 monoclonal antibodies exhibited potent antagonist activity in receptor binding and functional assays. The characterization of the macaque eotaxin/CCR3 axis and development of antagonistic anti-macaque CCR3 monoclonal antibodies will facilitate the development of CCR3 small molecule antagonists with the hope of ameliorating chronic inflammatory diseases in humans.


Assuntos
Anticorpos Monoclonais/biossíntese , Receptores de Quimiocinas/antagonistas & inibidores , Receptores de Quimiocinas/genética , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/uso terapêutico , Ligação Competitiva , Cálcio/metabolismo , Linhagem Celular , Quimiocina CCL11 , Quimiocina CCL5/fisiologia , Quimiocinas CC/genética , Quimiocinas CC/metabolismo , Quimiotaxia , Clonagem Molecular , Eosinófilos/fisiologia , Humanos , Macaca mulatta , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Receptores CCR3 , Receptores de Quimiocinas/química
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