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1.
MMWR Morb Mortal Wkly Rep ; 71(2): 37-42, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35025857

RESUMO

Opioid use disorder (OUD) is a significant public health problem in the United States, which affects children as well as adults. During 2010-2017, maternal opioid-related diagnoses increased approximately 130%, from 3.5 to 8.2 per 1,000 hospital deliveries, and neonatal abstinence syndrome (NAS) increased 83%, from 4.0 to 7.3 per 1,000 hospital deliveries (1). NAS, a withdrawal syndrome, can occur among infants following in utero exposure to opioids and other psychotropic substances (2). In 2018, a study of six states with mandated NAS case reporting for public health surveillance (2013-2017) found that mandated reporting helped quantify NAS incidence and guide programs and services (3). To review surveillance features and programmatic development in the same six states, a questionnaire and interview with state health department officials on postimplementation efforts were developed and implemented in 2021. All states reported ongoing challenges with initial case reporting, limited capacity to track social and developmental outcomes, and no requirement for long-term follow-up in state-mandated case reporting; only one state instituted health-related outcomes monitoring. The primary surveillance barrier beyond initial case reporting was lack of infrastructure. To serve identified needs of opioid- or other substance-exposed mother-infant dyads, state health departments reported programmatic successes expanding education and access to maternal medication for opioid use disorder (MOUD), community and provider education or support services, and partnerships with perinatal quality collaboratives. Development of additional infrastructure is needed for states aiming to advance NAS surveillance beyond initial case reporting.


Assuntos
Analgésicos Opioides/efeitos adversos , Notificação de Abuso , Síndrome de Abstinência Neonatal/epidemiologia , Avaliação de Programas e Projetos de Saúde , Vigilância em Saúde Pública , Seguimentos , Humanos , Pesquisa Qualitativa , Governo Estadual , Estados Unidos/epidemiologia
2.
BMC Cancer ; 14: 81, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24511912

RESUMO

BACKGROUND: Preclinical and clinical studies have shown for decades that tumor cells demonstrate significantly enhanced sensitivity to "fever range" hyperthermia (increasing the intratumoral temperature to 42-45°C) than normal cells, although it is unknown why cancer cells exhibit this distinctive susceptibility. METHODS: To address this issue, mammary epithelial cells and three malignant breast cancer lines were subjected to hyperthermic shock and microarray, bioinformatics, and network analysis of the global transcription changes was subsequently performed. RESULTS: Bioinformatics analysis differentiated the gene expression patterns that distinguish the heat shock response of normal cells from malignant breast cancer cells, revealing that the gene expression profiles of mammary epithelial cells are completely distinct from malignant breast cancer lines following this treatment. Using gene network analysis, we identified altered expression of transcripts involved in mitotic regulators, histones, and non-protein coding RNAs as the significant processes that differed between the hyperthermic response of mammary epithelial cells and breast cancer cells. We confirmed our data via qPCR and flow cytometric analysis to demonstrate that hyperthermia specifically disrupts the expression of key mitotic regulators and G2/M phase progression in the breast cancer cells. CONCLUSION: These data have identified molecular mechanisms by which breast cancer lines may exhibit enhanced susceptibility to hyperthermic shock.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Genômica/métodos , Temperatura Alta , Hipertermia Induzida/métodos , Linhagem Celular Tumoral , Suscetibilidade a Doenças/diagnóstico , Feminino , Febre , Redes Reguladoras de Genes/genética , Humanos , Células MCF-7 , Análise Serial de Proteínas
3.
PLoS One ; 8(9): e73508, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24039967

RESUMO

Green barley extract (GB) was investigated for possible anti-cancer activity by examining its anti-proliferative and pro-apoptotic properties on human leukemia/lymphoma cell lines. Our results indicate that GB exhibits selective anti-proliferative activity on a panel of leukemia/lymphoma cells in comparison to non-cancerous cells. Specifically, GB disrupted the cell-cycle progression within BJAB cells, as manifested by G2/M phase arrest and DNA fragmentation, and induced apoptosis, as evidenced by phosphatidylserine (PS) translocation to the outer cytoplasmic membrane in two B-lineage leukemia/lymphoma cell lines. The pro-apoptotic effect of GB was found to be independent of mitochondrial depolarization, thus implicating extrinsic cell death pathways to exert its cytotoxicity. Indeed, GB elicited an increase of TNF-α production, caspase-8 and caspase-3 activation, and PARP-1 cleavage within pre-B acute lymphoblastic leukemia Nalm-6 cells. Moreover, caspase-8 and caspase-3 activation and PARP-1 cleavage were strongly inhibited/blocked by the addition of the specific caspase inhibitors Z-VAD-FMK and Ac-DEVD-CHO. Furthermore, intracellular signaling analyses determined that GB treatment enhanced constitutive activation of Lck and Src tyrosine kinases in Nalm-6 cells. Taken together, these findings indicate that GB induced preferential anti-proliferative and pro-apoptotic signals within B-lineage leukemia/lymphoma cells, as determined by the following biochemical hallmarks of apoptosis: PS externalization, enhanced release of TNF-α, caspase-8 and caspase-3 activation, PARP-1 cleavage and DNA fragmentation Our observations reveal that GB has potential as an anti-leukemia/lymphoma agent alone or in combination with standard cancer therapies and thus warrants further evaluation in vivo to support these findings.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Hordeum/química , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Leucemia/metabolismo , Leucemia/patologia , Linfoma/metabolismo , Linfoma/patologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo
4.
Cancer Lett ; 337(2): 177-83, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23684928

RESUMO

This study examined the effect of 3, 9-dihydroxy-2-prenylcoumestan (pso), a furanocoumarin, on PC-3 and C4-2B castration-resistant prostate cancer (CRPC) cell lines. Pso caused significant G0/G1 cell cycle arrest and inhibition of cell growth. Molecular analysis of cyclin (D1, D2, D3, and E), cyclin-dependent kinase (cdk) (cdks 2, 4, and 6), and cdk inhibitor (p21 and p27) expression suggested transcriptional regulation of the cdk inhibitors and more significant downregulation of cdk4 than of cyclins or other cdks. Overexpression of cdk4, or silencing of p21 or p27, overcame pso-induced G0/G1 arrest, suggesting that G0/G1 cell cycle arrest is a potential mechanism of growth inhibition in CRPC cells.


Assuntos
Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Neoplasias da Próstata/enzimologia , Fase de Repouso do Ciclo Celular , Transdução de Sinais , Linhagem Celular Tumoral , Sobrevivência Celular , Quinase 4 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta a Droga , Fator de Transcrição E2F1/metabolismo , Furocumarinas/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Fosforilação , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Interferência de RNA , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transcrição Gênica , Transfecção
5.
Acta Trop ; 126(2): 127-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23416122

RESUMO

Malaria infection may be affected by host genetic factors as well as nutritional status. Iron status and the phenotype of haptoglobin, a heme-binding acute phase reactant may be determinants of malaria parasitemia. A combination of cross sectional studies and longitudinal follow-up were used to describe the association between iron status, C-reactive protein, malaria infections and host genetic factors including; haptoglobin (Hp) phenotypes, in children below 9 years in a malaria endemic area in Coastal Kenya. The prevalence of 0.45 and 0.41, respectively for Hp 1-1 and Hp 2-1 phenotypes was significantly higher than 0.14 for Hp 2-2 phenotype (n=162). Children with Hp 2-2 phenotype showed significantly higher iron storage compared to those with Hp 1-1 and Hp 2-1 phenotypes when children with malaria parasites and high C-reactive protein (>9mg/L) were excluded from the analysis. There were no significant differences in malaria parasite densities among Hp phenotypes but children with Hp 2-2 had lower number of clinical malaria episodes (P=0.045). Taken together, this study shows that the presence of malaria may complicate the interpretation of iron status in children based on their Hp-phenotypes. Further studies will be required to address possible interactions among the various genetic factors and iron status in a malaria endemic setting.


Assuntos
Doenças Endêmicas , Haptoglobinas/metabolismo , Ferro/metabolismo , Malária/epidemiologia , Polimorfismo Genético/genética , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Haptoglobinas/genética , Humanos , Lactente , Quênia/epidemiologia , Estudos Longitudinais , Malária/parasitologia , Masculino , Estado Nutricional , Parasitemia , Fenótipo , Plasmodium/fisiologia , Prevalência
6.
J Am Mosq Control Assoc ; 28(2): 79-83, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22894117

RESUMO

The mechanisms by which natural populations of vector mosquitoes cope with daily and seasonal fluctuations in temperature are poorly understood. We examined the effect of water temperature on expression of stress and immune-related genes in Aedes aegypti larvae. Aedes aegypti 3rd instars were exposed for 24 h to one of 7 constant temperatures (10 degrees C, 15 degrees C, 20 degrees C, 25 degrees C [control], 32 degrees C, 36 degrees C, or 40 degrees C) and expression of antimicrobial peptides (cecropin, defensin), transferrin, and heat shock proteins (HSP70 and HSP83) quantified by real-time reverse-transcriptase polymerase chain reaction. Cecropin, defensin, and transferrin were overexpressed at 36 degrees C and underexpressed at 15 degrees C and 32 degrees C. HSP83 was overexpressed at 10 degrees C and 40 degrees C and underexpressed at 20 degrees C, while HSP70 was underexpressed at 15 degrees C, 32 degrees C, and 36 degrees C. These findings suggest that antimicrobial peptides can serve as biomarkers of thermal stress and that HSP83 may buffer mosquito larvae against extreme temperatures.


Assuntos
Aedes/metabolismo , Regulação da Expressão Gênica , Aedes/crescimento & desenvolvimento , Aedes/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Florida , Proteínas de Choque Térmico/metabolismo , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Estresse Fisiológico , Temperatura , Transferrina/metabolismo
7.
Cytometry A ; 81(9): 797-805, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22674786

RESUMO

Biochemical studies have demonstrated that phosphorylation of lymphocyte cell kinase (p56(lck) ) is crucial for activation of signaling cascades following T cell receptor (TCR) stimulation. However, whether phosphorylation/dephosphorylation of the activating or inhibitory tyrosine residues occurs upon activation is controversial. Recent advances in intracellular staining of phospho-epitopes and cytometric analysis, requiring few cells, have opened up novel avenues for the field of immunological signaling. Here, we assessed p56(lck) phosphorylation, using a multiparameter flow-cytometric based detection method following T cell stimulation. Fixation and permeabilization in conjunction with zenon labeling technology and/or fluorescently labeled antibodies against total p56(lck) or cognate phospho-tyrosine (pY) residues or surface receptors were used for detection purposes. Our observations showed that activation of Jurkat or primary human T cells using H(2) O(2) or TCR-induced stimulation led to simultaneous phosphorylation of the activating tyrosine residue, Y394 and the inhibitory tyrosine residue, Y505 of p56(lck) . This was followed by downstream calcium flux and expression of T cell activation markers; CD69 and CD40 ligand (CD40L). However, the extent of measurable activation readouts depended on the optimal stimulatory conditions (temperature and/or stimuli combinations). Treatment of cells with a p56(lck) -specific inhibitor, PP2, abolished phosphorylation at either residue in a dose-dependent manner. Taken together, these observations show that TCR-induced stimulation of T cells led to simultaneous phosphorylation of p56(lck) residues. This implies that dephosphorylation of Y505 is not crucial for p56(lck) activity. Also, it is clear that cytometric analysis provides for a rapid, sensitive, and quantitative method to supplement biochemical studies on p56(lck) signaling pathways in T cells at single cell level.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Processamento de Proteína Pós-Traducional , Receptores de Antígenos de Linfócitos T/metabolismo , Tirosina/metabolismo , Adolescente , Adulto , Motivos de Aminoácidos , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Ligante de CD40/metabolismo , Sinalização do Cálcio , Humanos , Peróxido de Hidrogênio/farmacologia , Células Jurkat , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/antagonistas & inibidores , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/química , Pessoa de Meia-Idade , Fosforilação , Pirimidinas/farmacologia , Adulto Jovem
8.
Viral Immunol ; 24(4): 281-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21830900

RESUMO

Highly active anti-retroviral therapy (HAART) restores CD4(+) T-cell numbers in the periphery; however, its efficacy in restoring functional immunity is not fully elucidated. Here we evaluated longitudinal changes in the expression of several key markers of T-cell activation, namely CD40 ligand (CD154), OX40 (CD134), or CD69, after anti-CD3/CD28 activation, as well as levels of IL-12 production after Staphylococcus aureus Cowan stimulation in 28 HIV-infected adult patients. Patients were followed up to 12 mo post-HAART initiation. Viral burdens and CD4 cell counts were measured at the same time points. A control group of 15 HIV-uninfected adult subjects was included for comparison. Significant increases in CD40L and OX40 expression, but not of CD69 expression, were observed over time in the overall patient population, and more particularly in patients with baseline CD4 counts lower than or equal to 200 cells/µL, or those with baseline viral loads lower than or equal to 10(5) RNA copies/mL. Similar increases were seen for IL-12 production. Viral loads were inversely associated with CD40L expression or IL-12 production in a mixed linear model analysis, while CD4 counts were directly associated. CD40L expression and IL-12 production were significantly correlated. In conclusion, HAART-mediated control of viral replication led to partial restoration of CD40L upregulation/expression, and to increased IL-12 production, but the magnitude of the response depended on the baseline characteristics of the treated patients.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade , Ligante de CD40/biossíntese , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Interleucina-12/biossíntese , Adulto , Contagem de Linfócito CD4 , Feminino , HIV/isolamento & purificação , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Ligante OX40/biossíntese , Staphylococcus aureus/imunologia , Carga Viral , Viremia
9.
J Biol Chem ; 286(42): 36404-13, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21859712

RESUMO

HIV-1 infections lead to a progressive depletion of CD4 cells culminating in AIDS. The coreceptor usage by HIV varies from CCR5 (R5) tropic early in infection to CXCR4 (X4) tropic in later infections. Although the coreceptor switch from R5 to X4 tropic HIV is well associated with progression to AIDS, the role of CCR5 in disease progression especially in patients infected exclusively with R5 isolates throughout the disease remains enigmatic. To better understand the role of CCR5 and R5 tropic HIV envelope in AIDS pathogenesis, we asked whether the levels of CCR5 and/or HIV Env-mediated fusion determine apoptosis of bystander cells. We generated CD4(+) T cell lines expressing varying levels of CCR5 on the cell surface to show that CCR5 expression levels correlate with bystander apoptosis induction. The mechanism of apoptosis involved caspase-3 activation and mitochondrial depolarization and was dependent on gp41 fusion activity as confirmed by fusion-restricted gp41 point mutants and use of the fusion inhibitor T20. Interestingly, lower levels of CCR5 were able to support virus replication in the absence of bystander apoptosis. Our findings suggest that R5 HIV-1-mediated bystander apoptosis is dependent on both CCR5 expression levels as well as fusogenic activity of the Env glycoprotein.


Assuntos
Síndrome da Imunodeficiência Adquirida/metabolismo , Apoptose , Efeito Espectador , Regulação da Expressão Gênica , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/fisiologia , Receptores CCR5/biossíntese , Síndrome da Imunodeficiência Adquirida/genética , Linfócitos T CD4-Positivos/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Enfuvirtida , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Proteína gp41 do Envelope de HIV/antagonistas & inibidores , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/farmacologia , Inibidores da Fusão de HIV/farmacologia , Células HeLa , Humanos , Mutação , Fragmentos de Peptídeos/farmacologia , Receptores CCR5/genética , Tropismo Viral/efeitos dos fármacos , Tropismo Viral/fisiologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/fisiologia
10.
Mol Ther ; 18(11): 2028-37, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20648001

RESUMO

Dendritic cells (DCs) are potent antigen-presenting cells that play a critical role in the activation of T cells. RNA interference (RNAi)-mediated silencing of negative immunoregulatory molecules expressed by DCs may provide a strategy to enhance the potency of DC-based vaccines and immunotherapy. Ablation of suppressor of cytokine signaling-1 (SOCS-1) in antigen-presenting cells has been shown to enhance cellular immune response in mice. Here, we used a previously reported DC-targeting approach to deliver small interfering RNA (siRNA) against SOCS-1 to human myeloid-derived DCs (MDDCs). SOCS1-silencing in MDDCs resulted in enhanced cytokine responses to lipopolysaccharide (LPS) and a strong mixed-lymphocyte reaction. Moreover, only DCs treated with SOCS-1 siRNA, and not controls, elicited strong primary in vitro responses to well-characterized HLA-A*0201-restricted Melan-A/MART-1 and human immunodeficiency virus (HIV) Gag epitopes in naive CD8(+) T cells from healthy donors. Finally, stimulation of CD8(+) T cells from HIV-seropositive subjects with SOCS1-silenced DCs resulted in an augmented polyfunctional cytotoxic T-lymphocyte (CTL) response, suggesting that SOCS-1 silencing can restore functionally compromised T cells in HIV infection. Collectively, these results demonstrate the feasibility of DC3-9dR-mediated manipulation of DC function to enhance DC immunogenicity for potential vaccine or immunotherapeutic applications.


Assuntos
Células Dendríticas/imunologia , HIV/imunologia , RNA Interferente Pequeno/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T/imunologia , Apoptose , Western Blotting , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , Antígenos HLA-A/imunologia , Antígeno HLA-A2 , Humanos , Lipopolissacarídeos/farmacologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Fragmentos de Peptídeos/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/antagonistas & inibidores , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
11.
J Virol ; 83(3): 1193-200, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19019957

RESUMO

Understanding the molecular mechanisms underlying dysregulated immune responses in human immunodeficiency virus type 1 (HIV-1) infection is crucial for the control of HIV/AIDS. Despite the postulate that HIV envelope glycoprotein gp120-CD4 interactions lead to impaired T-cell responses, the precise mechanisms underlying such association are not clear. To address this, we analyzed Lck and F-actin redistribution into the immunological synapse in stimulated human primary CD4(+) T cells from HIV-1-infected donors. Similar experiments were performed with CD4(+) T cells from HIV-uninfected donors, which were exposed to anti-CD4 domain 1 antibodies, as an in vitro model of gp120-CD4 interactions, or aldithriol-inactivated HIV-1 virions before stimulation. CD4(+) T cells from HIV-infected patients exhibited a two- to threefold inhibition of both Lck and F-actin recruitment into the synapse, compared to cells from uninfected donors. Interestingly, defective recruitment of Lck was ameliorated following suppressive highly active antiretroviral therapy. Engagement of the CD4 receptor on T cells from HIV-uninfected donors before anti-CD3/CD28 stimulation led to similar defects. Furthermore, the redistribution of Lck into lipid rafts was abrogated by CD4 preengagement. Our results suggest that the engagement of CD4 by HIV gp120 prior to T-cell receptor stimulation leads to dysregulation of early signaling events and could consequently play an important role in impaired CD4(+) T-cell function.


Assuntos
Antígenos CD4/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , Sinapses Imunológicas , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Actinas/metabolismo , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1 , Humanos
12.
Microbes Infect ; 8(6): 1560-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16702009

RESUMO

There is clear evidence that most antimalarial drugs, while acting through different mechanisms, are associated with parasite growth/development inhibition and eventual parasite death. However, the exact mode of parasite death remains unclear. In the present study, we investigated the ability of various drugs, including two antimalarial drugs (chloroquine and atovaquone), a topoisemerase II inhibitor (etoposide) and a nitric oxide donor (S-nitro-N-acetyl-D, L-penicillamine), to induce apoptosis in a laboratory strain of Plasmodium falciparum. Results obtained from flow cytometric analysis showed a significant reduction in the percent of parasitemia and parasite growth in all drug-treated parasite cultures, including those treated with etoposide and S-nitro-N-acetyl-D, L-penicillamine. For further investigation, we used various biochemical approaches including the terminal dUTP nick-end labeling assay, determination of mitochondrial membrane integrity and DNA degradation/fragmentation, to analyze the changes occurring during parasite-drug interactions and eventual death. We observed that loss of membrane potential was induced in parasite cultures treated with atovaquone, while S-nitro-N-acetyl-D, L-penicillamine induced abnormal parasite forms, "crisis forms", and minor DNA degradation. However, these features were not observed in the parasite cultures treated with chloroquine nor were other features of apoptosis-like death associated with any of the drugs used in this study. The death resulting from the various drug treatments is atypical of apotosis. More studies will be needed to define the precise mode of death exhibited by P. falciparum.


Assuntos
Antimaláricos/farmacologia , Apoptose/efeitos dos fármacos , Eritrócitos/parasitologia , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Animais , Atovaquona , Células Cultivadas , Cloroquina/farmacologia , Fragmentação do DNA/efeitos dos fármacos , DNA de Protozoário/metabolismo , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Etoposídeo/farmacologia , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Malária Falciparum/tratamento farmacológico , Potenciais da Membrana/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Naftoquinonas/farmacologia , Doadores de Óxido Nítrico/farmacologia , Parasitemia/parasitologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Plasmodium falciparum/crescimento & desenvolvimento
13.
Haematologica ; 90(4): 552-4, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15820954

RESUMO

Although hemoglobinopathies such as alpha+ thalassemia and the sickle cell trait might contribute to anemia in African children, we hypothesized that they might also enhance iron absorption under circumstances of critical availability, and that this could attenuate their hematologic effects. We found no support for this hypothesis in a cohort of children living on the coast of Kenya.


Assuntos
Ferro da Dieta/metabolismo , Malária Falciparum/sangue , Estado Nutricional , Traço Falciforme/sangue , Talassemia alfa/sangue , Anemia Ferropriva/sangue , Criança , Pré-Escolar , Doenças Endêmicas , Feminino , Ferritinas/sangue , Humanos , Quênia/epidemiologia , Malária Falciparum/epidemiologia , Masculino , Talassemia alfa/imunologia
14.
Am J Clin Nutr ; 80(6): 1604-10, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15585775

RESUMO

BACKGROUND: The relation between malnutrition and malaria is controversial. On the one hand, malaria may cause malnutrition, whereas on the other hand, malnutrition itself may modulate susceptibility to the disease. OBJECTIVE: The objective was to investigate the association between Plasmodium falciparum malaria and malnutrition in a cohort of Kenyan children. DESIGN: The study involved the longitudinal follow-up of children aged 0-95 [corrected] mo for clinical malaria episodes and anthropometric measurements through 4 cross-sectional surveys. We used Poisson regression analysis to investigate the association between malaria and nutritional status. RESULTS: The crude incidence rate ratios (IRRs) for malaria during the 6-mo period before assessment in children defined as malnourished on the basis of low height-for-age or low weight-for-age z scores (<-2) were 1.17 (95% CI: 0.91, 1.50; P=0.21) and 0.94 (0.71, 1.25; P=0.67), respectively, which suggests no association between malaria and the subsequent development of protein-energy malnutrition. However, we found that age acted as an effect modifier in the association between malaria episodes and malnutrition on prospective follow-up. The IRR for malaria in children aged 0-2 y, who were subsequently characterized as underweight, was 1.65 (1.10, 2.20; P=0.01), and a significant overall relation between malaria and stunting was found on regression analysis after adjustment for the interaction with age (IRR: 1.91; 1.01, 3.58; P=0.04). CONCLUSION: Although children living on the coast of Kenya continue to experience clinical episodes of uncomplicated malaria throughout the first decade of life, the effect of malaria on nutritional status appears to be greatest during the first 2 y of life.


Assuntos
Transtornos da Nutrição Infantil/complicações , Transtornos da Nutrição Infantil/epidemiologia , Malária Falciparum/complicações , Malária Falciparum/epidemiologia , Desnutrição Proteico-Calórica/complicações , Desnutrição Proteico-Calórica/epidemiologia , Fatores Etários , Antropometria , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Humanos , Incidência , Lactente , Quênia/epidemiologia , Estudos Longitudinais , Masculino , Morbidade , Estado Nutricional , Prevalência , Análise de Regressão
15.
J Infect Dis ; 190(3): 439-47, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15243915

RESUMO

Both iron deficiency and malaria are common in much of sub-Saharan Africa, and the interaction between these conditions is complex. To investigate the association between nutritional iron status, immunoglobulins, and clinical Plasmodium falciparum malaria, we determined the incidence of malaria in a cohort of children between the ages of 8 months and 8 years who were living on the Kenyan coast. Biochemical iron status and malaria-specific immune responses were determined during 2 cross-sectional surveys. We found that the incidence of clinical malaria was significantly lower among iron-deficient children (incidence-rate ratio [IRR], 0.70; 95% confidence interval [CI], 0.51-0.99; P<.05), that the incidence of malaria was significantly associated with plasma ferritin concentration (IRR for log ferritin concentration, 1.48; 95% CI, 1.01-2.17; P<.05), and that iron status was strongly associated with a range of malaria-specific immunoglobulins. We conclude that iron deficiency was associated with protection from mild clinical malaria in our cohort of children in coastal Kenya and discuss possible mechanisms for this protection.


Assuntos
Anemia Ferropriva/complicações , Anemia Ferropriva/epidemiologia , Malária Falciparum/complicações , Malária Falciparum/epidemiologia , Animais , Especificidade de Anticorpos , Criança , Pré-Escolar , Estudos Transversais , Ferritinas/sangue , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Incidência , Lactente , Ferro/sangue , Quênia/epidemiologia , Estado Nutricional , Plasmodium falciparum/imunologia
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