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1.
Malays J Med Sci ; 28(1): 75-86, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33679223

RESUMO

BACKGROUND: Genetic factors increase the risk of type 2 diabetes mellitus (T2DM). Thus, family history status may be a useful public health tool for disease prevention. This study compared the nutritional status, knowledge level, and T2DM risk among young adults with and without a family history of diabetes in Malaysia. METHODS: A total of 288 university students aged 18 to 29 years participated in this comparative cross-sectional study. We assessed dietary intake, level of physical activity, knowledge of diabetes and T2DM risk. RESULTS: Respondents with a family history of diabetes had significantly higher weight (P = 0.003), body mass index (P < 0.001), waist circumference (P < 0.001), diabetes knowledge level (P < 0.005) and T2DM risk (P < 0.001). Ethnicity, fibre intake, T2DM risk score and knowledge about diabetes were significant contributors toward family history of diabetes (P = 0.025, 0.034, < 0.001 and 0.004, respectively). CONCLUSION: Young adults with a family history of diabetes had suboptimal nutritional status. Despite being more knowledgeable about diabetes, they did not practice a healthy lifestyle. Family history status can be used to screen young adults at the risk of developing T2DM for primary disease prevention.

2.
Malar J ; 14: 253, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-26099266

RESUMO

BACKGROUND: The activity of several well-known anti-malarials, including chloroquine (CQ), is attributed to their ability to inhibit the formation of haemozoin (Hz) in the malaria parasite. The formation of inert Hz, or malaria pigment, from toxic haem acquired from the host red blood cell of the parasite during haemoglobin digestion represents a pathway essential for parasite survival. Inhibition of this critical pathway therefore remains a desirable target for novel anti-malarials. A recent publication described the results of a haem fractionation assay used to directly determine haemoglobin, free haem and Hz in Plasmodium falciparum inoculated with CQ. CQ was shown to cause a dose-dependent increase in cellular-free haem that was correlated with decreased parasite survival. The method provided valuable information but was limited due to its low throughput and high demand on parasite starting material. Here, this haem fractionation assay has been successfully adapted to a higher throughput method in 24-well plates, significantly reducing lead times and starting material volumes. METHODS: All major haem species in P. falciparum trophozoites, isolated through a series of cellular fractionation steps were determined spectrophotometrically in aqueous pyridine (5 % v/v, pH 7.5) as a low spin complex with haematin. Cell counts were determined using a haemocytometer and a rapid novel fluorescent flow cytometry method. RESULTS: A higher throughput haem fractionation assay in 24-well plates, containing at most ten million trophozoites was validated against the original published method using CQ and its robustness was confirmed. It provided a minimum six-fold improvement in productivity and 24-fold reduction in starting material volume. The assay was successfully applied to amodiaquine (AQ), which was shown to inhibit Hz formation, while the antifolate pyrimethamine (PYR) and the mitochondrial electron transporter inhibitor atovaquone (Atov) demonstrated no increase in toxic cellular free haem. CONCLUSIONS: This higher throughput cellular haem fractionation assay can easily be applied to novel anti-malarials with a significantly decreased lead time, providing a valuable tool with which to probe the mechanisms of action of both new and established anti-malarials.


Assuntos
Antimaláricos/farmacologia , Colorimetria/métodos , Heme/análise , Plasmodium falciparum/efeitos dos fármacos , Trofozoítos/efeitos dos fármacos , Amodiaquina/farmacologia , Atovaquona/farmacologia , Cloroquina/farmacologia , Pirimetamina/farmacologia
3.
Cell Biochem Funct ; 33(2): 59-66, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25663587

RESUMO

Tissue degradation and leukocyte extravasation suggest proteolytic destruction of the extracellular matrix (ECM) during severe malaria. Matrix metalloproteinases (MMPs) play an established role in ECM turnover, and increased MMP-9 protein abundance is correlated with malarial infection. The malaria pigment hemozoin (Hz) is a heme detoxification biomineral that is produced during infection and associated with biologically active lipid peroxidation products such as 4-hydroxynonenal (HNE) adsorbed to its surface. Hz has innate immunomodulatory activity, and many of its effects can be reproduced by exogenously added HNE. Hz phagocytosis enhances MMP-9 expression in monocytes; thus, this study was designed to examine the ability of HNE to alter MMP-9 regulation in activated cells of macrophage lineage. Data show that treatment of lipopolysaccharide-stimulated RAW 264.7 cells with HNE increased MMP-9 secretion and activity. HNE treatment abolished the cognate tissue inhibitor of metalloproteinase-1 protein levels, further decreasing MMP-9 regulation. Phosphorylation of both p38 mitogen-activated protein kinase (MAPK) and c-Jun NH2-terminal kinase was induced by HNE, but only p38 MAPK inhibition lessened MMP-9 secretion. These results demonstrate the in vitro ability of HNE to cause MMP-9 dysregulation in an activated cell model. The findings may extend to myriad pathologies associated with lipid peroxidation and elevated MMP-9 levels leading to tissue damage.


Assuntos
Aldeídos/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Lipopolissacarídeos/metabolismo , Macrófagos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Animais , Linhagem Celular , Peroxidação de Lipídeos , Macrófagos/imunologia , Camundongos , Fosforilação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
N Z Med J ; 131(1479): 64-71, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30048434

RESUMO

AIM: The Waitemata District Health Board (DHB) aimed to investigate and improve the accuracy of its reporting of post-partum haemorrhage (PPH), to understand its true incidence. METHOD: The quality improvement project included multidisciplinary collaboration between maternity clinicians and clinical coders, substantive redesign of the Waitemata DHB's birth documentation form, systematic auditing and follow-up of clinical documentation by a dedicated quality midwife, linking of maternity clinicians to a key designated senior coder and ongoing PPH incidence monitoring and staff education. RESULTS: The coded rate of PPH has risen dramatically and is now in line with expected Australasian incidence levels. A corresponding increase in the value of cost-weighted discharges (estimated at $544,000 for the 2015/16 financial year) was realised as a result of the more accurate reported incidence. CONCLUSION: This case illustrates the value of coding to a clinical service and the importance of clinical leadership and engagement in achieving successful and sustainable service redesign initiatives. It provides an example of how to evaluate and update coding and a process for changing the way clinicians and coders work that could benefit other services in Waitemata DHB as well as in other New Zealand district health boards.


Assuntos
Codificação Clínica/normas , Hemorragia Pós-Parto/epidemiologia , Melhoria de Qualidade/normas , Feminino , Maternidades/normas , Maternidades/estatística & dados numéricos , Humanos , Incidência , Serviços de Saúde Materna/normas , Serviços de Saúde Materna/estatística & dados numéricos , Prontuários Médicos/normas , Nova Zelândia/epidemiologia , Alta do Paciente/normas , Gravidez
5.
Eur J Med Chem ; 152: 489-514, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29754074

RESUMO

Design, synthesis, structure-activity relationship, cytotoxicity studies, in silico drug-likeness, genotoxicity screening, and in vivo studies of new 1-aryl-3-substituted propanol derivatives led to the identification of nine compounds with promising in vitro (55, 56, 61, 64, 66, and 70-73) and in vivo (66 and 72) antimalarial profiles against Plasmodium falciparum and Plasmodium berghei. Compounds 55, 56, 61, 64, 66 and 70-73 exhibited potent antiplasmodial activity against chloroquine-resistant strain FCR-3 (IC50s < 0.28 µM), and compounds 55, 56, 64, 70, 71, and 72 showed potent biological activity in chloroquine-sensitive and multidrug-resistant strains (IC50s < 0.7 µM for 3D7, D6, FCR-3 and C235). All of these compounds share appropriate drug-likeness profiles and adequate selectivity indexes (77 < SI < 184) as well as lack genotoxicity. In vivo efficacy tests in a mouse model showed compounds 66 and 72 to be promising candidates as they exhibited significant parasitemia reductions of 96.4% and 80.4%, respectively. Additional studies such as liver stage and sporogony inhibition, target exploration of heat shock protein 90 of P. falciparum, targeted delivery by immunoliposomes, and enantiomer characterization were performed and strongly reinforce the hypothesis of 1-aryl-3-substituted propanol derivatives as promising antimalarial compounds.


Assuntos
Antimaláricos/farmacologia , Sistemas de Liberação de Medicamentos , Parasitemia/tratamento farmacológico , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Propanóis/farmacologia , Animais , Antimaláricos/síntese química , Antimaláricos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Camundongos , Estrutura Molecular , Parasitemia/parasitologia , Testes de Sensibilidade Parasitária , Plasmodium berghei/crescimento & desenvolvimento , Plasmodium falciparum/crescimento & desenvolvimento , Propanóis/síntese química , Propanóis/química , Relação Estrutura-Atividade
6.
Cryst Growth Des ; 16(5): 2542-2551, 2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27175104

RESUMO

Hemozoin is a unique biomineral that results from the sequestration of toxic free heme liberated as a consequence of hemoglobin degradation in the malaria parasite. Synthetic neutral lipid droplets (SNLDs) and phospholipids were previously shown to support the rapid formation of ß-hematin, abiological hemozoin, under physiologically relevant pH and temperature, though the mechanism by which heme crystallization occurs remains unclear. Detergents are particularly interesting as a template because they are amphiphilic molecules that spontaneously organize into nanostructures and have been previously shown to mediate ß-hematin formation. Here, 11 detergents were investigated to elucidate the physicochemical properties that best recapitulate crystal formation in the parasite. A strong correlation between the detergent's molecular structure and the corresponding kinetics of ß-hematin formation was observed, where higher molecular weight polar chains promoted faster reactions. The larger hydrophilic chains correlated to the detergent's ability to rapidly sequester heme into the lipophilic core, allowing for crystal nucleation to occur. The data presented here suggest that detergent nanostructures promote ß-hematin formation in a similar manner to SNLDs and phospholipids. Through understanding mediator properties that promote optimal crystal formation, we are able to establish an in vitro assay to probe this drug target pathway.

7.
Int J Parasitol Drugs Drug Resist ; 6(3): 184-198, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27718413

RESUMO

Synthesis of new 1-aryl-3-substituted propanol derivatives followed by structure-activity relationship, in silico drug-likeness, cytotoxicity, genotoxicity, in silico metabolism, in silico pharmacophore modeling, and in vivo studies led to the identification of compounds 22 and 23 with significant in vitro antiplasmodial activity against drug sensitive (D6 IC50 ≤ 0.19 µM) and multidrug resistant (FCR-3 IC50 ≤ 0.40 µM and C235 IC50 ≤ 0.28 µM) strains of Plasmodium falciparum. Adequate selectivity index and absence of genotoxicity was also observed. Notably, compound 22 displays excellent parasitemia reduction (98 ± 1%), and complete cure with all treated mice surviving through the entire period with no signs of toxicity. One important factor is the agreement between in vitro potency and in vivo studies. Target exploration was performed; this chemotype series exhibits an alternative antimalarial mechanism.


Assuntos
Amino Álcoois/isolamento & purificação , Amino Álcoois/farmacologia , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Amino Álcoois/efeitos adversos , Amino Álcoois/uso terapêutico , Animais , Antimaláricos/efeitos adversos , Antimaláricos/uso terapêutico , Modelos Animais de Doenças , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Concentração Inibidora 50 , Malária Falciparum/tratamento farmacológico , Camundongos , Relação Estrutura-Atividade , Análise de Sobrevida , Resultado do Tratamento
8.
Int J Parasitol Drugs Drug Resist ; 5(3): 84-91, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26150923

RESUMO

The Malaria Box, assembled by the Medicines for Malaria Venture, is a set of 400 structurally diverse, commercially available compounds with demonstrated activity against blood-stage Plasmodium falciparum. The compounds are a representative subset of the 20,000 in vitro antimalarials identified from the high-throughput screening efforts of St. Jude Children's Research Hospital (TN, USA), Novartis and GlaxoSmithKline. In addition, a small set of active compounds from commercially available libraries was added to this group, but it has not previously been published. Elucidation of the biochemical pathways on which these compounds act is a major challenge; therefore, access to these compounds has been made available free of charge to the investigator community. Here, the Malaria Box compounds were tested for activity against the formation of ß-hematin, a synthetic form of the heme detoxification biomineral, hemozoin. Further, the mechanism of action of these compounds within the malaria parasite was explored. Ten of the Malaria Box compounds demonstrated significant inhibition of ß-hematin formation. In this assay, dose-response data revealed IC50 values ranging from 8.7 to 22.7 µM for these hits, each of which is more potent than chloroquine (a known inhibitor of hemozoin formation). The in vitro antimalarial activity of these ten hits was confirmed in cultures of the chloroquine sensitive D6 strain of the parasite resulting in IC50 values of 135-2165 nM, followed by testing in the multidrug resistant strain, C235. Cultures of P. falciparum (D6) were then examined for their heme distribution following treatment with nine of the commercially available confirmed compounds, seven of which disrupted the hemozoin pathway.


Assuntos
Antimaláricos/farmacologia , Hemeproteínas/antagonistas & inibidores , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/química , Heme/classificação , Estrutura Molecular
9.
Int J Parasitol Drugs Drug Resist ; 4(3): 316-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25516843

RESUMO

The emergence of drug resistant strains of Plasmodium spp. creates a critical need for the development of novel antimalarials. Formation of hemozoin, a crystalline heme detoxification process vital to parasite survival serves as an important drug target. The quinoline antimalarials including chloroquine and amodiaquine owe their antimalarial activity to inhibition of hemozoin formation. Though in vivo formation of hemozoin occurs within the presence of neutral lipids, the lipophilic detergent NP-40 was previously shown to serve as a surrogate in the ß-hematin (synthetic hemozoin) formation process. Consequently, an NP-40 mediated ß-hematin formation assay was developed for use in high-throughput screening. Here, the assay was utilized to screen 144,330 compounds for the identification of inhibitors of crystallization, resulting in 530 hits. To establish the effectiveness of these target-based ß-hematin inhibitors against Plasmodium falciparum, each hit was further tested in cultures of parasitized red blood cells. This effort revealed that 171 of the ß-hematin inhibitors are also active against the parasite. Dose-response data identified 73 of these ß-hematin inhibitors have IC50 values ⩽5 µM, including 25 compounds with nanomolar activity against P. falciparum. A scaffold-based analysis of this data identified 14 primary scaffolds that represent 46% of the 530 total hits. Representative compounds from each of the classes were further assessed for hemozoin inhibitory activity in P. falciparum infected human erythrocytes. Each of the hit compounds tested were found to be positive inhibitors, while a negative control did not perturb this biological pathway in culture.

10.
Future Med Chem ; 5(12): 1437-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23919553

RESUMO

Recent initiatives to develop more effective and affordable drugs, controlling mosquitoes and development of a preventative vaccine have been launched with the goal of completely eradicating malaria. To this end, Novartis (Surrey, UK) and GlaxoSmithKline (Middlesex, UK) screened their chemical libraries of approximately two million small molecules for antimalarial properties, which resulted in a set of over 20,000 'highly druggable' initial hits. Efforts in academia are centered on specific pathway targets. One such high-throughput screening effort has been focused on hemozoin formation, a unique heme detoxification pathway found in the malaria parasite. This review discusses the current approaches and limitations of high-throughput screening discovery of hemozoin inhibitors. In the future, new methods must be developed to validate the mechanism of action of these hit compounds within the parasite.


Assuntos
Antimaláricos/química , Hemeproteínas/antagonistas & inibidores , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Heme/química , Hemeproteínas/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Malária/tratamento farmacológico , Malária/parasitologia , Plasmodium falciparum/efeitos dos fármacos
11.
Disabil Rehabil ; 35(14): 1149-63, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23083416

RESUMO

PURPOSE: Chronic pain, posttraumatic stress disorder (PTSD), and depression are common outcomes following traumatic injury. Yet, screening and early intervention to prevent the onset of these disorders do not occur routinely in acute trauma settings. This pilot study examined the clinical utility of screening and early multidisciplinary intervention for reducing disability following traumatic injury. METHOD: 142 non-severe head injured trauma inpatients (26% female, Injury Severity Score M = 9.65, M age = 36 years) were assessed for injury-related factors, pain, and psychological function within 4 weeks post injury. Patients were randomly allocated to a Multidisciplinary Intervention (MI) or Usual Care (UC) group. MI patients received assessment and treatment at one and 3 months post injury from pain and rehabilitation medicine doctors, physiotherapists, occupational therapists, and clinical psychologists. Outcomes at 6 months were then compared. RESULTS: Acute pain intensity, posttraumatic adjustment, depression and acute trauma symptoms, and alcohol use predicted a significant 26%, 49%, 56%, and 30% of the variance in pain, depressive, and PTSD severity, and physical mobility respectively at 6 months. Despite MI group patients reporting no improvement in the severity of pain and psychological symptoms, these patients reported significantly improved relief from pain symptoms as a result of treatment at 6 months. Twenty four per cent of the UC group initially below the cut-off for being at risk of developing PTSD/Depression received new clinical diagnoses at 6 months compared with none of the 'not at risk' MI group attendees who remained asymptomatic. CONCLUSIONS: Early findings point to the value of early screening to identify patients at risk of treatable pain, physical, and psychological impairments. Moreover, early multidisciplinary intervention models following traumatic injury show promise for protecting against the onset of posttraumatic psychological disorders.


Assuntos
Lesões Encefálicas/psicologia , Depressão/terapia , Transtornos de Estresse Pós-Traumáticos/terapia , Adaptação Psicológica , Adulto , Idoso , Depressão/diagnóstico , Depressão/psicologia , Avaliação da Deficiência , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/psicologia , Medição da Dor , Administração dos Cuidados ao Paciente , Equipe de Assistência ao Paciente , Projetos Piloto , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Resultado do Tratamento , Austrália Ocidental
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