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1.
Exp Parasitol ; 239: 108286, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35660529

RESUMO

Leishmania donovani, an obligate intracellular parasite, the causative agent of visceral leishmaniasis is known to subvert the host immune system for its own survival. Although the precise mechanism is still unknown, emerging evidences indicate that L. donovani efficiently suppress MHC I mediated antigen presentation, rendering inadequate CD8+T cell activation and weakening host defense against parasite. The role of transcription factor EB (TFEB) was recognized in modulating antigen presentation besides its role in lysosomal biogenesis and function. Here, we investigated the regulatory role of TFEB in the modulation of presentation of Leishmania antigen in host tissue. Our results showed an increased expression of TFEB after Leishmania infection both in vitro and in vivo and there was a decrease in the expression of Th-1 cytokine IFNγ along with MHC class I and CD8+T cells indicating attenuation of cell mediated immunity and possibly MHC I restricted antigen presentation. Silencing of TFEB resulted in increased expression of IFNγ and MHC I along with increased CD8+T cells population without any significant change in CD4+T cell number. We also observed a decreased parasite burden in TFEB silenced condition which indicates enhanced parasite clearance by alteration of immunological response possibly through induction of presentation of Leishmania antigen through MHC I. The present study explains the role of TFEB silencing in parasite clearance through regulating the antigen presentation of Leishmania antigen thereby promises to formulate a potential therapeutic strategy against visceral leishmaniasis.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Animais , Apresentação de Antígeno , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/imunologia , Controle de Doenças Transmissíveis , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Fatores de Transcrição/imunologia
2.
BMC Pregnancy Childbirth ; 21(1): 820, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893054

RESUMO

BACKGROUND: Postpartum family planning (PPFP) helps women space childbirths, increase exclusive breastfeeding and prevent unintended pregnancies, leading to reduction in maternal, infant and child morbidities and mortality. Unmet need of family planning is highest among women in the postpartum period due to lack of knowledge, cultural and religious barriers, access barriers and low antenatal care service utilization. However, in spite of low prevalence of postpartum family planning practices, birth-to-birth interval is reportedly high in Delhi, India. This study explores the postpartum contraception practices and the relationship between use of postpartum contraception and subsequent child linear growth. METHODS: This is a mixed method cohort study on PPFP and is nested within an ongoing "Women and Infants Integrated Interventions for Growth Study" (WINGS). Married women aged 18-30 years who have delivered a live baby are recruited for quantitative interviews at 6 weeks, 6, 12, and 24 months postpartum. In-depth interviews are conducted with a randomly selected sub-sample of women at each of the four time points, 35 husbands and 20 local service providers to understand their perspectives on PPFP practices. DISCUSSION: The findings from the study will provide useful insights into couples' contraception preferences and choice of contraception, modern and traditional, initiation time and the effect of birth spacing and contraception use on subsequent linear growth of the child. This knowledge will be of significant public health relevance and will help in designing appropriate interventions for appropriate postpartum contraception use and delivery strategies. The study aims to work address the Sexual and Reproductive Health and Rights goal of promoting reproductive health, voluntary and safe sexual and reproductive choices for women. TRIAL REGISTRATION: Trial registration number: CTRI/2020/03/023954 .


Assuntos
Estudos Clínicos como Assunto , Comportamento Contraceptivo/etnologia , Anticoncepção/métodos , Serviços de Planejamento Familiar/métodos , Período Pós-Parto/etnologia , Adolescente , Adulto , Intervalo entre Nascimentos/etnologia , Desenvolvimento Infantil , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Índia , População Urbana , Adulto Jovem
3.
Exp Parasitol ; 217: 107948, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32698076

RESUMO

Immunomodulation is an emerging concept to combat infection in recent years. Immunomodulators like arabinosylated-lipoarabinomannan (Ara-LAM) and glycyrrhizic-acid (GA) possess anti-leishmanial property, whereas sodium-antimony-gluconate (SAG) is still considered as the first choice for chemotherapy against leishmaniasis. During infection, invasion of Leishmania donovani needs the potential requirement of Ca2+, which is further responsible for apoptosis in intracellular amastigotes. However, suppression of elevated intracellular calcium by the activation of plasma-membrane-calcium-ATPase (PMCA4) facilitates survival of L. donovani in the host. In the present study, SAG, Ara-LAM, and GA were found to evoke significant increase in intracellular Ca2+ in L. donovani infected macrophages by inhibiting PMCA4. Moreover, PMCA4 inhibition by TFP or PMCA4 siRNA elevated the level of PKCß, whereas calcium-independent upregulation of PKCζ remained unchanged in infected macrophages. Furthermore, application of immunomodulators in infected macrophages resulted in down-regulation of PKCζ, conversion of anti-inflammatory to pro-inflammatory cytokines and inhibition of PMCA4. Plasma membrane-associated ceramide which is known to be elevated during leishmaniasis, triggered upregulation of PMCA4 via PKCζ activation. Interestingly, immunomodulators attenuated ceramide generation, which resulted into reduced PKCζ activation leading to the decreased PMCA expression in infected macrophages. Therefore, our study elucidated the efficacy of SAG, Ara-LAM, and GA in the reduction of parasite burden in macrophages by suppressing PMCA activation through inhibition of ceramide mediated upregulation of PKCζ.


Assuntos
Antiprotozoários/uso terapêutico , ATPases Transportadoras de Cálcio/sangue , Membrana Celular/enzimologia , Fatores Imunológicos/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Animais , Gluconato de Antimônio e Sódio/farmacologia , Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/farmacologia , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Ceramidas/metabolismo , Meios de Cultura Livres de Soro , Densitometria , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Ácido Glicirrízico/farmacologia , Ácido Glicirrízico/uso terapêutico , Imipramina/farmacologia , Immunoblotting , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/uso terapêutico , Macrófagos/fisiologia , Camundongos , RNA de Protozoário/genética , RNA de Protozoário/isolamento & purificação , RNA Interferente Pequeno/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Reversa , Transfecção
4.
Microb Pathog ; 128: 41-46, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30578837

RESUMO

Acute Vibrio cholerae infection triggers significant inflammatory response and immense fluid secretion in the intestine. In the present study, methyl gallate (MG) isolated from Terminalia chebula was evaluated to determine the in vivo fluid accumulation-inhibitory, anticolonization and anti-inflammatory and in vitro biofilm-inhibitory activities against multi-drug resistant (MDR) V. cholerae. Bacterial membrane-damaging and biofilm-inhibitory activities were determined by membrane perturbation and transmission electron microscopy (TEM); and microdilution assays, respectively. Fluid accumulation-inhibitory and anticolonization activities of MG (23.80-95.23 mg/kg body weight) were determined in 4-5 days old BALB/c mice with an incubation time of 18 h. The effect of MG (1, 50 and 500 mg/kg body weight) on intestinal inflammatory reaction induced by V. cholerae was studied by performing histology in Swiss albino mice. MIC and MBC of MG against the test strains were 32-64 and 64-256 µg/ml, respectively. MG showed the fluid accumulation-inhibitory activity with inhibition values of 42.86-89.08% at doses between 23.80 and 95.23 mg/kg body weight and significant anticolonization activity (p < 0.0001) against V. choleare in the suckling mouse intestine. MG (500 mg/kg body weight) significantly inhibited the inflammatory reactions induced by V. cholerae compared to the vehicle control. MG exhibited 70% minimum biofilm inhibition concentration of 64 µg/ml and bacterial membrane damaging activity at 1 × MBC. The results obtained in the present study suggest that MG has potential as an effective agent for the treatment of severe secretory and inflammatory diarrheal disease caused by MDR V. cholerae.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Biofilmes/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Ácido Gálico/análogos & derivados , Terminalia/química , Vibrio cholerae/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Membrana Celular/efeitos dos fármacos , Cólera/microbiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Ácido Gálico/administração & dosagem , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Intestino Delgado/patologia , Intestino Delgado/virologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Vibrio cholerae/citologia , Vibrio cholerae/crescimento & desenvolvimento , Vibrio cholerae/patogenicidade
5.
Ther Adv Chronic Dis ; 15: 20406223231223286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250743

RESUMO

The development of a biosimilar is based on comparative structural, physicochemical, functional and clinical assessments. The sum of these analyses encompasses the 'totality of evidence', which demonstrates no clinically meaningful differences between the biosimilar and the reference product (RP). Once biosimilarity has been established, provided there is suitable scientific justification, clinical data may be extrapolated to other indications of the RP. AVT02 has been developed as a biosimilar to high-concentration, low-volume Humira (adalimumab), an anti-tumour necrosis factor-alpha monoclonal antibody approved for various chronic inflammatory indications. The totality of evidence for AVT02 is described, supporting its approval as an adalimumab biosimilar for all approved indications globally. Analytical similarity assessments using mass spectrometry methods demonstrated identical amino acid sequences for AVT02 and the RP, with high similarity in terms of primary structure, post-translational modifications and higher-order structural attributes. The mechanism of action was assessed by various cell-based potency assays and binding assays, and the results demonstrated that AVT02 is highly similar to the RP. No clinically meaningful differences in terms of purity, potency and safety were observed, and minor differences in a few physiochemical attributes did not impact the in vitro biologic activity and were not considered clinically relevant. Clinical similarity was demonstrated by comparing the pharmacokinetic, efficacy, safety and immunogenicity profiles of AVT02 with those of the RP. Clinical studies supported similar pharmacokinetic and comparable immunogenicity profiles between AVT02 and the RP in healthy participants and participants with moderate-to-severe chronic plaque psoriasis, with no new safety signals detected. The totality of evidence described demonstrates the biosimilarity of AVT02 to the RP, thereby fulfilling the scientific and regulatory requirements for AVT02 as a high-concentration biosimilar for the treatment of chronic plaque psoriasis and all approved indications of the RP.


Demonstrating the high similarity between the biosimilar AVT02 (adalimumab) and Humira, supporting AVT02 to be used to treat all conditions currently treated with Humira Biosimilars are drugs that have similar quality, effectiveness, and safety profiles to an already approved biological drug, which is referred to as the 'reference product (RP)'. Although biosimilars have identical amino acids (the building blocks that make up proteins) to the RPs, they are manufactured in living cells which leads to a small amount of natural variability. Therefore, extensive testing is required to confirm that a biosimilar is highly similar to the RP. The 'totality of evidence' is a set of tests to demonstrate that there are no meaningful differences between the biosimilar and the RP, in other words, that there is 'biosimilarity' between the biosimilar and RP. Once biosimilarity has been proven, the biosimilar may be used to treat all the diseases currently treated with the RP, without the need for separate clinical trials in each disease. AVT02 has been developed as a biosimilar to Humira, an antibody approved for various chronic inflammatory diseases such as chronic plaque psoriasis (PsO). A step-by-step approach was used to show biosimilarity of AVT02 to Humira. This included clinical studies (in healthy individuals and participants with moderate to severe chronic PsO) and non-clinical studies (comparisons of the chemistry of the drugs and how they work in the body). Clinical studies in healthy individuals and participants with PsO showed that AVT02 and Humira were taken up and degraded by the body in a similar way, peoples' immune response to the two drugs were similar, and both drugs had similar side effects. No clinically meaningful differences in the purity, effectiveness, and safety of AVT02 compared with Humira were seen. The evidence demonstrates the biosimilarity of AVT02 to Humira and supports the use of AVT02 to treat all conditions which are currently treated with Humira.

6.
Bioinorg Chem Appl ; 2024: 1018375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601021

RESUMO

Nowadays, the search for new chemotherapeutic agents with low toxicity and high selectivity is a major concern. In this paper, we report the synthesis and characterization of a hybrid thiosemicarbazone/hydrazone ligand in its neutral form (L1H2) and as the chloride salt ([L1H3]Cl)-, three diorganotin (IV) complexes, and one complex with Sn (IV). The compounds have been fully characterized by IR, mass spectra, 1H, 13C, and 119Sn NMR, 119Sn CP/MAS NMR, and by single crystal X-ray diffraction. The organotin compounds have the empirical formula [SnR2L1] (R = Me, Bu, and Ph), but in the solid state, they are polymeric species with seven coordination number due to weak coordination of the pyridine nitrogen, whereas in solution, the polymeric structure is lost to afford hexacoordinate monomeric species. Reaction with SnI4 yields complex [Sn (L1)2]·EtOH, with the metal in a distorted dodecahedral arrangement. We have evaluated the antiproliferative activity of the two forms of the ligands and the four coordination compounds against MDA-MB-231, HeLa, PC3, and HepG2 cancer cell lines, and WI-38 normal cell line, and all the compounds present higher activity than cisplatin, used as the standard control. To investigate the mode of action, we have selected the most active complex, containing phenyl substituents, and used the triple negative breast cancer cell line MDA-MB-231. The results show that the complex induces apoptotic cell death promoted by generation of reactive oxygen species and by disruption of mitochondrial membrane potential.

7.
PLoS One ; 17(3): e0264777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275948

RESUMO

BACKGROUND: The impact of infertility on mental, emotional, physical and sexual health is grave, particularly in a pronatalist society. Literature is replete with evidence of wide ranging psychosocial consequences of infertility in women, indicating the need for identifying the gaps and designing appropriate context specific interventions to improve access and utilization of services. Data that are accessible, primarily from infertility clinics and women visiting hospitals for infertility treatment; information from community settings is rare. This is a protocol paper for a study to understand women's experiences and actions taken by them to cope with delayed conception. METHODS: Mixed-methods cross-sectional design is used to obtain deep insights into the experiences of delayed conception, coping mechanisms, medical assistance and other help sought. Information is also being obtained on socio-demographic profile, fertility intentions, fertility quality of life, general medical history, obstetric, gynecological and sexual history, substance use and mental health status. A sample of 1530 women will be administered 4 modules of a quantitative survey. Focus group discussions, about four or till saturation point, will be conducted using purposive sampling. The study is recruiting from a population of women who previously participated in the 'Women and Infants Integrated Interventions for Growth Study (WINGS) and failed to conceive during 18 months follow up period. Data collected through questionnaire will be assembled, cleaned, analyzed and reported. The findings will be disseminated through reports with the ethics review committee, government entities, academic and research publications. DISCUSSION: This study will provide insights on the experiences and coping strategies of women with delayed conception in the study community. Results will assist in designing appropriate interventions to meet the holistic health and psychosocial needs of women with delayed conception and promote sexual and reproductive health within the broader framework of Sustainable Development Goals and Universal health coverage. TRIAL REGISTRATION: Trial registration number: CTRI/2020/03/023955.


Assuntos
Infertilidade , Qualidade de Vida , Adaptação Psicológica , Estudos Transversais , Feminino , Clínicas de Fertilização , Humanos , Lactente , Gravidez
8.
Front Glob Womens Health ; 3: 816969, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35425937

RESUMO

Objective: To estimate utilization of maternal, perinatal healthcare services after the lockdown was implemented in response to the COVID-19 pandemic compared to the period before. Methods: This study conducted in Dakshinpuri, an urban neighborhood in Delhi, reports data over a 13-month period which includes the period "before lockdown" i.e., October 1, 2019 to March 21, 2020 and "after lockdown" i.e., March 22 to November 5, 2020. The period "after lockdown" included the lockdown phase (March 22 to May 31, 2020) and unlock phase (June 1 to November 5, 2020). Mothers delivered during this period in the study area were interviewed using semi-structured questionnaires. In-depth interviews (IDIs) were conducted in a subsample to understand the experiences, challenges, and factors for underutilization of healthcare services. Findings: The survey covered a total population of 21,025 in 4,762 households; 199 eligible mothers (mean age 27.4 years) were interviewed. In women who delivered after lockdown against before lockdown, adjusted odds of having >2 antenatal care visits in the third trimester was 80% lower (aOR 0.2, 95% CI 0.1-0.5); proportion of institutional deliveries was lower (93 vs. 97%); exclusive breastfeeding during first 6 months of birth (64.5 vs. 75.7%) and health worker home visitation within 6 weeks of birth (median, 1 vs. 3 visits) were substantially lower. Fear of contracting COVID-19, poor quality of services, lack of transportation and financial constraints were key issues faced by mothers in accessing health care. More than three-fourth (81%) of the mothers reported feeling down, depressed or hopeless after lockdown. The major factors for stress during lockdown was financial reasons (70%), followed by health-related concerns. Conclusion: COVID-19 pandemic-related lockdown substantially affected maternal and perinatal healthcare utilization and service delivery.

9.
J Family Med Prim Care ; 10(11): 4182-4188, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35136786

RESUMO

BACKGROUND: Caesarean section (C-section) delivery is a serious maternal health concern in the long run. Notedly, there is a lack of studies dealing with understanding the ways and reasons of C-section deliveries becoming a public health issue in today's time in India and the measures to reduce the unnecessary caesarean sections. We have conducted this study to study the changes in the state-wise prevalence of C-section deliveries in India and understand C-section delivery's socioeconomic and biomedical predictors. MATERIALS AND METHODS: The study uses data from the fourth and fifth rounds of the National Family Health Surveys (NFHS). The per cent differences in the C-section deliveries from NFHS-4 to NFHS-5 across the states were measured through relative changes. The association between the C-section delivery and socioeconomic and biomedical factors were assessed using multiple logistic regression. RESULTS: This study revealed that the C-section deliveries are higher in the southern states than in the other parts of India. Literacy plays a vital role in C-section deliveries. The probabilities of C-section deliveries are more in 30-40 and 40 + years. The women belonging to the median wealth index category were more likely (OR-CI, 1.62 [1.55-1.66]) to undergo the C-section followed by the women from wealthy households (OR-CI, 1.46 [1.41-1.52]). CONCLUSION: The Government's health policymakers should take the initiative to reduce the C-section section delivery by means of building maternal health literacy and awareness among women and the community so that its future implications can be minimised. It is crucial to formulate a mandate and implement it in the states where C-sections are too high through community health workers and primary care providers.

10.
Mol Cell Neurosci ; 37(4): 657-62, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18313940

RESUMO

The control of RNA stability is an important post-transcriptional event. While neural development is known to require proteins that bind AU-rich elements (ARE) and affect RNA half-life, the role of specific RNA stability in this process remains elusive. In the Drosophila embryo, glial fate acquisition is triggered by glial cells missing (gcm) master gene, which is transiently expressed in all gliogenic stem cells and submitted to tight transcriptional regulation. By using in vitro and in vivo site directed mutagenesis, we have discovered that gcm RNA is unstable and that its 3'UTR confers labile properties to RNA due to the presence of an ARE motif. Moreover, we show that the gliogenic potential of Gcm transcription factor increases when ARE is abolished and demonstrate the importance of gcm RNA stability in the acquisition of the glial fate. Thus, control of a single RNA half-life is crucial for nervous system differentiation.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Neuroglia/fisiologia , Estabilidade de RNA/genética , Fatores de Transcrição/genética , Regiões 3' não Traduzidas/genética , Adenosina/genética , Animais , Sequência de Bases , Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/genética , Dados de Sequência Molecular , Neuroglia/citologia , Fatores de Transcrição/fisiologia , Uridina/genética
11.
Biochim Biophys Acta ; 1769(9-10): 541-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17804093

RESUMO

NIPP1 is a ubiquitously expressed nuclear protein that represses the transcription of targeted genes. Here we show that the transcriptional repression by NIPP1 is alleviated by the RNAi-mediated knockdown of EED and EZH2, two core components of the Polycomb Repressive Complex 2 (PRC2), and by the overexpression of a catalytically dead mutant of the histone methyltransferase EZH2. NIPP1 is present in a complex with EED and EZH2 in vivo and has distinct binding sites for these proteins. These data disclose an essential role for the PRC2 complex in the transcriptional repression by NIPP1.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endorribonucleases/metabolismo , Complexos Multiproteicos/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/fisiologia , Sítios de Ligação/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Endorribonucleases/genética , Proteína Potenciadora do Homólogo 2 de Zeste , Humanos , Complexos Multiproteicos/genética , Fosfoproteínas Fosfatases/genética , Complexo Repressor Polycomb 2 , Proteínas do Grupo Polycomb , Ligação Proteica/genética , Proteínas de Ligação a RNA/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética
12.
PLoS One ; 9(10): e110843, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25329062

RESUMO

Calcium is an ubiquitous cellular signaling molecule that controls a variety of cellular processes and is strictly maintained in the cellular compartments by the coordination of various Ca2+ pumps and channels. Two such fundamental calcium pumps are plasma membrane calcium ATPase (PMCA) and Sarco/endoplasmic reticulum calcium ATPase (SERCA) which play a pivotal role in maintaining intracellular calcium homeostasis. This intracellular Ca2+ homeostasis is often disturbed by the protozoan parasite Leishmania donovani, the causative organism of visceral leishmaniasis. In the present study we have dileneated the involvement of PMCA4 and SERCA3 during leishmaniasis. We have observed that during leishmaniasis, intracellular Ca2+ concentration was up-regulated and was further controlled by both PMCA4 and SERCA3. Inhibition of these two Ca2+-ATPases resulted in decreased parasite burden within the host macrophages due to enhanced intracellular Ca2+. Contrastingly, on the other hand, activation of PMCA4 was found to enhance the parasite burden. Our findings also highlighted the importance of Ca2+ in the modulation of cytokine balance during leishmaniasis. These results thus cumulatively suggests that these two Ca2+-ATPases play prominent roles during visceral leishmaniasis.


Assuntos
Cálcio/metabolismo , Leishmaniose Visceral/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Sinalização do Cálcio/genética , Homeostase/genética , Humanos , Leishmania donovani/parasitologia , Leishmania donovani/patogenicidade , Leishmaniose Visceral/parasitologia , Macrófagos/metabolismo , Macrófagos/parasitologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Transdução de Sinais/genética
13.
FEMS Immunol Med Microbiol ; 60(1): 18-27, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20528929

RESUMO

We show here that oral immunization with purified outer membrane vesicles (OMVs) of Vibrio cholerae induces a prolonged high rise in the protective antibody titre. Rabbit immune sera were vibriocidal against the homologous and against several heterologous V. cholerae strains in vitro. In addition, OMV immunization conferred significant protective immunity against subsequent bacterial challenges. Thirty OMV-immunized rabbits were challenged with different V. cholerae strains; each challenged group contained five immunized and three unimmunized animals. All the immunized rabbits survived bacterial challenges and were healthy after 24 h, except the two from each group that received the SG24 and SG06 strains, respectively, which developed watery diarrhoea. In contrast, all the unimmunized animals developed cholera-like symptoms, with a death toll of eight within 24 h of challenge. This is the first report of the induction of protective immunity by V. cholerae OMVs in a rabbit model (removable intestinal tie-adult rabbit diarrhoea) that mimics the human disease. Finally, OMVs were found to be significantly less reactogenic than the live and the heat-killed bacteria. Our studies show that oral immunization with OMVs of V. cholerae may induce long-term immunity and may be useful as a 'nonliving' vaccine candidate for the future.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas contra Cólera/imunologia , Cólera/prevenção & controle , Vesículas Secretórias/imunologia , Vibrio cholerae/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/administração & dosagem , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Cólera/patologia , Vacinas contra Cólera/administração & dosagem , Diarreia/patologia , Diarreia/prevenção & controle , Modelos Animais de Doenças , Feminino , Masculino , Coelhos , Ensaios de Anticorpos Bactericidas Séricos , Análise de Sobrevida
14.
J Infect ; 54(5): 475-82, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17087996

RESUMO

OBJECTIVES: To determine whether Vibrio cholerae strains with similar phage types are also genetically homogeneous or heterogeneous by molecular typing methods like PFGE and RAPD-PCR employed in this study. METHODS: A total of 26 V. cholerae O1 and O139 strains received from different parts of India were analyzed by using conventional phage typing method, antibiogram and molecular typing methods such as PFGE and RAPD-PCR. RESULTS: Both O1 and O139 strains were resistant against two antibiotics (Ampicillin and Furazolidone) were detected. All of these strains were clustered in a single phage type, i.e., Type 27 for V. cholerae O1 and Type 1 for V. cholerae O139. Extensive molecular characterization by RAPD and PFGE showed that six sets of O1 and O139 strains, each comprising two strains, had identical PFGE and RAPD profiles. Only one O139 strain (PL-4) had unique RAPD and PFGE profile among all the 26 V. cholerae strains used in this study. CONCLUSION: Apart from serology, the strains of V. cholerae can be discriminated by this conventional phage typing system that offers the basic information on identification, biotyping and discrimination of strains. But, a high level of heterogeneity was observed in RAPD and PFGE profiles indicating the clonal diversity of V. cholerae O1 and O139 strains. It was concluded that these strains were phenotypically identical through phage typing system and antibiogram but genetically dissimilar, as shown in molecular typing systems.


Assuntos
Cólera/epidemiologia , Vibrio cholerae O139 , Vibrio cholerae O1 , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Tipagem de Bacteriófagos , Cólera/microbiologia , Eletroforese em Gel de Campo Pulsado , Humanos , Índia/epidemiologia , Testes de Sensibilidade Microbiana , Fenótipo , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Vibrio cholerae O1/classificação , Vibrio cholerae O1/genética , Vibrio cholerae O1/isolamento & purificação , Vibrio cholerae O139/classificação , Vibrio cholerae O139/genética , Vibrio cholerae O139/isolamento & purificação
15.
J Biol Chem ; 278(33): 30677-85, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12788942

RESUMO

The nuclear protein NIPP1 (nuclear inhibitor of protein Ser/Thr phosphatase-1) interacts with the splicing factors SAP155 and CDC5L and is involved in a late step of spliceosome assembly. In addition, NIPP1 is an interactor of protein phosphatase-1 and a COOH-terminal NIPP1 fragment displays an RNase E like endoribonuclease activity. A yeast two-hybrid screening resulted in the identification of the Polycomb group protein EED (embryonic ectoderm development), an established transcriptional repressor, as a novel NIPP1 interactor. NIPP1 only interacted with full-length EED, whereas two EED interaction domains were mapped to the central and COOH-terminal thirds of NIPP1. The NIPP1-EED interaction was potentiated by the binding of (d)G-rich nucleic acids to the central domain of NIPP1. Nucleic acids also decreased the potency of NIPP1 as an inhibitor of PP1, but they did not prevent the formation of a ternary NIPP1.EED.PP1 complex. EED had no effect on the function of NIPP1 as a splicing factor or as an endoribonuclease. However, similar to EED, NIPP1 acted as a transcriptional repressor of targeted genes and this NIPP1 effect was mediated by the EED interaction domain. Also, the histone deacetylase 2 was present in a complex with NIPP1. Our data are in accordance with a role for NIPP1 as a DNA-targeting protein for EED and associated chromatin-modifying enzymes.


Assuntos
Proteínas de Transporte/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Fosfoproteínas Fosfatases/metabolismo , Proteínas de Ligação a RNA , Proteínas Repressoras/metabolismo , Transcrição Gênica/fisiologia , Animais , Células COS , Precipitação Química , Endorribonucleases/metabolismo , Biblioteca Gênica , Células HeLa , Humanos , Camundongos , Mutagênese Sítio-Dirigida , Complexo Repressor Polycomb 2 , Proteína Fosfatase 1 , RNA/metabolismo , Coelhos , Proteínas Repressoras/genética , Spliceossomos/metabolismo , Supressão Genética , Técnicas do Sistema de Duplo-Híbrido , Leveduras
16.
Dev Biol ; 255(1): 138-50, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12618139

RESUMO

Neuronal differentiation relies on proneural factors that also integrate positional information and contribute to the specification of the neuronal type. The molecular pathway triggering glial specification is not understood yet. In Drosophila, all lateral glial precursors and glial-promoting activity have been identified, which provides us with a unique opportunity to dissect the regulatory pathways controlling glial differentiation and specification. Although glial lineages are very heterogeneous with respect to position, time of differentiation, and lineage tree, they all express and require two homologous genes, glial cell deficient/glial cell missing (glide/gcm) and glide2, that act in concert, with glide/gcm constituting the major glial-promoting factor. Here, we show that glial specification resides in glide/gcm transcriptional regulation. The glide/gcm promoter contains lineage-specific elements as well as quantitative and turmoil elements scattered throughout several kilobases. Interestingly, there is no correlation between a specific regulatory element and the type of glial lineage. Thus, the glial-promoting factor acts as a naive switch-on button that triggers gliogenesis in response to multiple pathways converging onto its promoter. Both negative and positive regulation are required to control glide/gcm expression, indicating that gliogenesis is actively repressed in some neural lineages.


Assuntos
Sistema Nervoso Central/citologia , Sistema Nervoso Central/embriologia , Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Neuroglia/citologia , Transcrição Gênica , Animais , Axônios/patologia , Sequência de Bases , Biomarcadores , Diferenciação Celular , Linhagem da Célula , Drosophila/embriologia , Embrião não Mamífero , Genes de Insetos , Homozigoto , Modelos Neurológicos , Mutação , Fenótipo , Regiões Promotoras Genéticas , Células-Tronco/citologia , Fatores de Tempo , Transgenes
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