Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Microbes Infect ; : 105340, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663721

RESUMO

Our developed cell division-specific 'centrin' gene deleted Leishmania donovani (LdCen1-/-) the causative parasite of the fatal visceral-leishmaniasis (VL), exhibits a selective growth arrest at the intracellular stage and is anticipated as a live attenuated vaccine candidate against VL. LdCen1-/- immunization in animals has shown increased IFN-γ secreting CD4+ and CD8+ T cells along with protection conferred by a protective proinflammatory immune response. A label-free proteomics approach has been employed to understand the physiology of infection and predict disease interceptors during Leishmania-host interactions. Proteomic modulation after infection of human macrophage cell lines suggested elevated annexin A6, implying involvement in various biological processes such as membrane repair, transport, actin dynamics, cell proliferation, survival, differentiation, and inflammation, thereby potentiating its immunological protective capacity. Additionally, S100A8 and S100A9 proteins, known for maintaining homeostatic balance in regulating the inflammatory response, have been upregulated after infection. The inhibitory clade of serpins, known to inhibit cysteine proteases (CPs), was upregulated in host cells after 48 h of infection. This is reflected in the diminished expression of CPs in the parasites during infection. Such proteome analysis confirms LdCen1-/- efficacy as a vaccine candidate and predicts potential markers in future vaccine development strategies against infectious diseases.

2.
ACS Omega ; 9(4): 4455-4465, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313517

RESUMO

The current research aims to develop a carrier system for the delivery of a matrix metalloproteinase (MMP) inhibitor along with a bioceramic agent to the periodontal pocket. It is proposed that the present system, if given along with a systemic antibiotic, would be a fruitful approach for periodontitis amelioration. To fulfill the aforementioned objective, a doxycycline hyclate- and hydroxyapatite-adsorbed composite was prepared by a physical adsorption method and successfully loaded inside sodium alginate-chitosan nanoparticles and optimized based on particle size and drug content. Optimized formulation was then subjected to different evaluation parameters like encapsulation efficiency, hydroxyapatite content, ζ potential, surface morphology, in vitro drug release, cell line studies, and stability studies. For the optimized formulation, particle size, polydispersity index (PDI), entrapment efficiency, ζ potential, and drug content were found to be 336.50 nm, 0.23, 41.77%, -13.85 mV, and 14.00%, respectively. The surface morphology of the placebo and adsorbed composite-loaded nanoparticles as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the spherical shape and rough surface of the particles. In gingival crevicular fluid (GCF) 7.6, a sustained drug release profile was obtained up to 36 h. In vitro % viability studies performed on murine fibroblast cells (NIH3T3) and human periodontal ligament (hPDL) cell lines confirmed the proliferative nature of the formulation. Also, when subjected to stability studies for 4 weeks, particle size, PDI, and drug content did not vary considerably, thereby ensuring the stable nature of nanoparticles. Henceforth, sodium alginate-chitosan nanoparticles appeared to be a good carrier system for doxycycline hyclate and hydroxyapatite for periodontal therapy. If given along with a system antibiotic, the system will serve as a fruitful tool for infection-mediated periodontal regeneration and healing.

3.
J Sep Sci ; 46(21): e2300582, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37675810

RESUMO

The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet-visible and Fourier-transform infrared spectroscopy. The purity of berberine was ascertained by thin-layer chromatography using n-propanol-formic acid-water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44-49 with compact spots (diameter 0.2-0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 µm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13-1.16 and 1.40-1.71, respectively. A comparison has shown that both thin-layer chromatography and high-performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis.


Assuntos
Berberina , Berberina/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Solventes/análise , Água
4.
Curr Probl Cardiol ; 48(7): 101666, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36828041

RESUMO

A considerable epidemiological and pathogenetic overlap exists between tuberculosis (TB) and cardiovascular diseases (CVD). The objective of this study was to establish the prevalence of CVD in the TB population. A systematic literature search was performed using Scopus, PubMed, EBSCO, ProQuest, Web of Science on January 25, 2023 using the keywords: "Tuberculosis," "TB," "mycobacterium tuberculosis," and "cardiovascular disease," "CVD" and with individual terms of various CVDs. Observational Studies were included if they reported the prevalence of CVD in the presence of TB in an adult population. The Newcastle-Ottawa Scale was used for quality evaluation. Statistical analyses were performed using STATA version 17. From 10 studies involving 46715 TB patients, a combined prevalence of CVDs was found to be 11% (CI: 95%, 5-16) with significant heterogeneity across studies (I2 = 96.72%). This study showed a considerable prevalence of CVD among TB patients suggesting TB patients to consider cardiac examination.


Assuntos
Doenças Cardiovasculares , Mycobacterium tuberculosis , Tuberculose , Adulto , Humanos , Tuberculose/diagnóstico , Prevalência , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
5.
Lancet Public Health ; 7(4): e305-e315, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35338849

RESUMO

BACKGROUND: In low-incidence countries, tuberculosis mainly affects migrants, mostly resulting from reactivation of latent tuberculosis infection (LTBI) acquired in high-incidence countries before migration. A nationwide primary care-based LTBI testing and treatment programme for migrants from high-incidence countries was therefore established in high tuberculosis incidence areas in England. We aimed to assess the effectiveness of this programme. METHODS: We did a retrospective, population-based cohort study of migrants who registered in primary care between Jan 1, 2011, and Dec 31, 2018, in 55 high-burden areas with programmatic LTBI testing and treatment. Eligible individuals were aged 16-35 years, born in a high-incidence country, and had entered England in the past 5 years. Individuals who tested interferon-γ release assay (IGRA)-negative were advised about symptoms of tuberculosis, whereas those who tested IGRA-positive were clinically assessed to rule out active tuberculosis and offered preventive therapy. The primary outcome was incident tuberculosis notified to the national Enhanced Tuberculosis Surveillance system. FINDINGS: Our cohort comprised 368 097 eligible individuals who had registered in primary care, of whom 37 268 (10·1%) were tested by the programme. 1446 incident cases of tuberculosis were identified: 166 cases in individuals who had IGRA testing (incidence 204 cases [95% CI 176-238] per 100 000 person-years) and 1280 in individuals without IGRA testing (82 cases [77-86] per 100 000 person-years). Overall, in our primary analysis including all diagnosed tuberculosis cases, a time-varying association was identified between LTBI testing and treatment and lower risk of incident tuberculosis (hazard ratio [HR] 0·76 [95% CI 0·63-0·91]) when compared with no testing. In stratified analysis by follow-up period, the intervention was associated with higher risk of tuberculosis diagnosis during the first 6 months of follow-up (9·93 [7·63-12·9) and a lower risk after 6 months (0·57 [0·41-0·79]). IGRA-positive individuals had higher risk of tuberculosis diagnosis than IGRA-negative individuals (31·9 [20·4-49·8]). Of 37 268 migrants who were tested, 6640 (17·8%) were IGRA-positive, of whom 1740 (26·2%) started preventive treatment. LTBI treatment lowered the risk of tuberculosis: of 135 incident cases in the IGRA-positive cohort, seven cases were diagnosed in the treated group (1·87 cases [95% CI 0·89-3·93] per 1000 person-years) and 128 cases were diagnosed in the untreated group (10·9 cases [9·16-12·9] per 1000 person-years; HR 0·14 [95% CI 0·06-0·32]). INTERPRETATION: A low proportion of eligible migrants were tested by the programme and a small proportion of those testing positive started treatment. Despite this, programmatic LTBI testing and treatment of individuals migrating to a low-incidence region is effective at diagnosing active tuberculosis earlier and lowers the long-term risk of progression to tuberculosis. Increasing programme participation and treatment rates for those testing positive could substantially impact national tuberculosis incidence. FUNDING: National Institute for Health Research Health Protection Research Unit in Respiratory Infections.


Assuntos
Tuberculose Latente , Migrantes , Adolescente , Adulto , Estudos de Coortes , Inglaterra/epidemiologia , Humanos , Tuberculose Latente/diagnóstico , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/epidemiologia , Estudos Retrospectivos , Adulto Jovem
6.
Parasitol Int ; 75: 102047, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31887394

RESUMO

Leishmania donovani, a protozoan parasite of family Trypanosomatidae, causes fatal visceral leishmaniasis (VL) in the Indian subcontinent and Africa and cutaneous leishmaniasis (CL) in Sri Lanka. Another member of Trypanosomatidae, Leptomonas seymouri, resembling Leishmania was discovered recently to co-exist with L. donovani in the clinical samples from India and Sri Lanka and therefore, interfere with its investigations. We earlier described a method for selective elimination of such co-existing L. seymouri from clinical samples of VL exploiting the differential growth of the parasites at 37 °C in vitro. Here, we explored ways for a rapid discriminatory diagnosis using high resolution melting (HRM) curves to detect co-occurring L. seymouri with L. donovani in clinical samples. Initial attempt with kDNA-minicircle (mitochondrial DNA) based HRM did not display different Tm values between L. donovani and L. seymouri. Surprisingly, all of their minicircle sequences co-existed in similar clades in the dendrogram analysis, although the kDNA sequences are known for its species and strain specific variations among the Trypanosomatids. However, an HRM analysis that targets the HSP70 gene successfully recognized the presence of L. seymouri in the clinical isolates. This discovery will facilitate rapid diagnosis of L. seymouri and further investigations in to this elusive organism, including the clinico-pathological implications of its co-existence with L. donovani in patients.


Assuntos
Coinfecção/diagnóstico , Infecções por Euglenozoa/diagnóstico , Leishmania donovani/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Trypanosomatina/isolamento & purificação , DNA de Cinetoplasto/análise
7.
Lancet Infect Dis ; 19(11): 1191-1201, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31471131

RESUMO

BACKGROUND: Evaluating interventions that might lead to a reduction in tuberculosis in high-income countries with a low incidence of the disease is key to accelerate progress towards its elimination. In such countries, migrants are known to contribute a large proportion of tuberculosis cases to the burden. We assessed the effectiveness of screening for active tuberculosis before entry to the UK and for latent tuberculosis infection (LTBI) post-entry for reduction of tuberculosis in new-entrant migrants to the UK. Additionally, we investigated the effect of access to primary care on tuberculosis incidence in this population. METHODS: We did a retrospective, population-based cohort study of migrants from 66 countries who were negative for active tuberculosis at pre-entry screening between Jan 1, 2011, and Dec 31, 2014, and eligible for LTBI screening. We used record linkage to track their first contact with primary care, uptake of LTBI screening, and development of active tuberculosis in England, Wales, and Northern Ireland. To assess the effectiveness of the pre-entry screening programme, we identified a control group of migrants who were not screened for active tuberculosis using the specific code for new entrants to the UK registering in primary care within the National Health Service patient registration data system. Our primary outcome was development of active tuberculosis notified to the National Enhanced Tuberculosis Surveillance System. FINDINGS: Our cohort comprised 224 234 migrants who were screened for active tuberculosis before entry to the UK and a control group of 118 738 migrants who were not. 103 990 (50%) migrants who were screened for active tuberculosis registered in primary care; all individuals in the control group were registered in primary care. 1828 tuberculosis cases were identified during the cohort time, of which 31 were prevalent. There were 26 incident active tuberculosis cases in migrants with no evidence of primary care registration, and 1771 cases in the entire cohort of migrants who registered in primary care (n=222 728), giving an incidence rate of 174 (95% CI 166-182) per 100 000 person-years. 672 (1%) of 103 990 migrants who were screened for active tuberculosis went on to develop tuberculosis compared with 1099 (1%) of 118 738 not screened for active tuberculosis (incidence rate ratio [IRR] 1·49, 95% CI 1·33-1·67; p<0·0001). 2451 (1%) of the 222 728 migrants registered in primary care were screened for LTBI, of whom 421 (17%) tested positive and 1961 (80%) tested negative; none developed active tuberculosis within the observed time period. Migrants settling in the least deprived areas had a decreased risk of developing tuberculosis (IRR 0·74, 95% CI 0·62-0·89; p=0·002), and time from UK arrival to primary care registration of 1 year or longer was associated with increased risk of active tuberculosis (2·96, 2·59-3·38; p<0·0001). INTERPRETATION: Pre-entry tuberculosis screening, early primary care registration, and LTBI screening are strongly and independently associated with a lower tuberculosis incidence in new-entrant migrants. FUNDING: National Institute for Health Research (NIHR) Health Protection Research Unit in Respiratory Infections and NIHR Imperial Biomedical Research Centre.


Assuntos
Emigrantes e Imigrantes , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Tuberculose Latente/diagnóstico , Programas de Rastreamento/métodos , Programas de Rastreamento/organização & administração , Administração em Saúde Pública/métodos , Adolescente , Adulto , Testes Diagnósticos de Rotina/métodos , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Tuberculose Latente/epidemiologia , Masculino , Irlanda do Norte/epidemiologia , Estudos Retrospectivos , País de Gales/epidemiologia , Adulto Jovem
8.
Int J Hematol Oncol Stem Cell Res ; 12(1): 14-22, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29951173

RESUMO

Background: Chronic myeloid leukemia (CML) is a hematological disorder caused by fusion of BCR and ABL genes. BCR-ABL dependent and independent pathways play equally important role in CML. TGFß-Smad pathway, an important BCR -ABL independent pathway, has scarce data in CML. Present study investigate the association between TGFß-Smad pathway and CML. Materials and Methods: Sixty-four CML patients and age matched healthy controls (n=63) were enrolled in this study. Patients were segregated into responder and resistant groups depending on their response to Imatinib mesylate (IM). TGFß1 serum levels were evaluated by ELISA and transcript levels of TGFß1 receptors, SMAD4 and SMAD7 were evaluated by Real-Time PCR. Sequencing of exons and exon-intron boundaries of study genes was performed using Next Generation Sequencing (NGS) in 20 CML patients. Statistical analysis was performed using SPSS version 16.0. Results:TGFß1 serum levels were significantly elevated (p = 0.02) and TGFßR2 and SMAD4 were significantly down-regulated (p = 0.012 and p = 0.043 respectively) in the patients. c.69A>G in TGFß1, c.1024+24G>A in TGFßR1 and g.46474746C>T in SMAD7 were the most important genetic variants observed with their presence in 10/20, 8/20 and 7/20 patients respectively. In addition, TGFßR1 transcript levels were reduced in CML patients with c.69A>G mutation. None of the genes differed significantly in terms of expression or genetic variants between responder and resistant patient groups. Conclusion: Our findings demonstrate the role of differential expression and genetic variants of TGFß-Smad pathway in CML. Decreased TGFßR2 and SMAD4 levels observed in the present study may be responsible for reduced tumor suppressive effects of this pathway in CML.

9.
Biochim Biophys Acta Mol Cell Res ; 1865(8): 1148-1159, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29800602

RESUMO

Expression of the intracellular form amastigote specific genes in the Leishmania donovani parasite plays a major role in parasite replication in the macrophage. In the current work, we have characterized a novel hypothetical gene, Ld30b that is specifically transcribed in the intracellular stage of the parasite. The recombinant Ld30b protein exists as a pentamer in solution as identified by native-PAGE and size exclusion gel chromatography. Structural analysis using circular dichroism and molecular modeling indicate that Ld30b belongs to family of cAMP-dependent protein kinase type I-alpha regulatory subunit. Co-localization immunofluorescence microscopy and western blot analyses (using anti-Ld30b antibody and anti-hypoxanthine-guanine phosphoribosyl transferase, a glycosome marker) on the isolated parasite glycosome organelle fractions show that Ld30b is localized in glycosome, though lacked a glycosome targeting PTS1/2 signal in the protein sequence. Episomal expression of Ld30b in the parasite caused the arrest of promastigotes and amastigotes growth in vitro. Cell cycle analysis using flow cytometry indicates that these parasites are arrested in 'sub G0/G1' phase of the cell cycle. Single allele knockout of Ld30b in the parasite similarly attenuated its growth by accumulation of cells in the S phase of cell cycle, thus confirming the probable importance of appropriate level of protein in the cells. Studying such intracellular stage expressing genes might unravel novel regulatory pathways for the development of drugs or vaccine candidates against leishmaniasis.


Assuntos
Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Leishmania donovani/fisiologia , Ciclo Celular , Dicroísmo Circular , Clonagem Molecular , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/química , Regulação da Expressão Gênica no Desenvolvimento , Leishmania donovani/genética , Microcorpos/química , Microcorpos/metabolismo , Modelos Moleculares , Filogenia , Multimerização Proteica , Estrutura Secundária de Proteína , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...