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1.
Soc Sci Med ; 351: 116928, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38772211

ABSTRACT

Social capital, defined as the nature of the social relationship and the resources embedded within the social network of an individual or community, influences how individuals within a group interact and collaborate within their communities or organizations. While it is acknowledged that social capital can be drawn from as a coping strategy to mitigate financial stress, there is a notable absence of the lived experience in the literature on how social capital influences households to tap resources from their social network. We have investigated the role of social capital in healthcare financing in rural Uttar Pradesh, India, highlighting the challenges faced by households in managing healthcare expenses. We took a qualitative research approach, conducting in-depth interviews with 24 households in the Hardoi District of Uttar Pradesh in August 2017 to explore participants' lived experience of accruing support from their community during their healthcare crisis. Data analysis followed a thematic content analysis approach. The study finds that households leverage social capital for both financial and non-financial support during health crises. Social networks, trust, and community cohesion play critical roles in resource acquisition. However, overreliance on social capital can be coercive, leading to inequity, privacy invasion, and dependency. Though social capital serves as a crucial resource of support in healthcare emergencies, its unequal distribution and potential for misuse highlight the need for more structured health financing policies in India. The findings underscore the importance of integrating community-driven resources into broader health financing strategies, considering local social structures and community dynamics.


Subject(s)
Healthcare Financing , Qualitative Research , Rural Population , Social Capital , Humans , India , Rural Population/statistics & numerical data , Female , Male , Adult , Middle Aged , Social Support
2.
Life (Basel) ; 12(7)2022 Jun 22.
Article in English | MEDLINE | ID: mdl-35888024

ABSTRACT

The evidence for fibroblast heterogeneity is continuously increasing, and recent work has shed some light on the existence of different sub-populations of fibroblasts in the human skin. Although we now have a more precise understanding of their distribution in the human body, we do not know whether their properties are predictive of where these cells derive from or whether these sub-types have functional consequences. In this study, we employed single-cell transcriptomics (10X Genomics) to study gene expression and segregate fibroblast sub-populations based on their genetic signature. We report the differential expression of a defined set of genes in fibroblasts from human skin, which may contribute to their dynamicity in vivo and in vitro. We show that the sub-population of fibroblasts expressing cytoskeletal markers, such as ANXA2, VIM, ACTB, are enriched in an adult skin sample. Interestingly, this sub-population of fibroblasts is not enriched in a neonatal skin sample but becomes predominant when neonatal fibroblasts are cultivated. On the other hand, the fibroblast sub-populations expressing COL1A1 and ELN are enriched in neonatal skin but are reduced in the adult skin and in fibroblasts from neonatal skin that are cultured in vitro. Our results indicate that fibroblasts are a dynamic cell type, and while their genetic make-up changes markedly, only a handful of genes belonging to the same functional pathway govern this alteration. The gene expression pattern of cytoskeletal markers may help in identifying whether the fibroblasts were isolated from an adult or an infant or whether they were cultivated, and this information could be useful for quality control in clinics and in cell banking. Furthermore, this study opens additional avenues to investigate the role of these markers in defining the complexity of human dermal fibroblasts.

3.
Cells ; 11(14)2022 07 09.
Article in English | MEDLINE | ID: mdl-35883599

ABSTRACT

The basal layer of human interfollicular epidermis has been described to harbour both quiescent keratinocyte stem cells and a transit amplifying cell population that maintains the suprabasal epidermal layers. We performed immunofluorescence analyses and revealed that the main proliferative keratinocyte pool in vivo resides suprabasally. We isolated from the human epidermis two distinct cell populations, the basal and the suprabasal keratinocytes, according to the expression of integrin ß4 (iß4). We compared basal iß4+ or suprabasal iß4- keratinocytes with respect to their proliferation and colony-forming ability and their Raman spectral properties. In addition, we generated dermo-epidermal substitutes using freshly isolated and sorted basal iß4+ or suprabasal iß4- keratinocytes and transplanted them on immuno-compromised rats. We show that suprabasal iß4- keratinocytes acquire a similar proliferative capacity as basal iß4+ keratinocytes after two weeks of culture in vitro, with expression of high levels of iß4 and downregulation of K10 expression. In addition, both basal iß4+ and suprabasal iß4- keratinocytes acquire authentic self-renewing properties during the in vitro 3D-culture phase and are able to generate and maintain a fully stratified epidermis for 16 weeks in vivo. Therefore, against the leading dogma, we propose that human suprabasal keratinocytes can retro-differentiate into true basal stem cells in a wound situation and/or when in contact with the basement membrane.


Subject(s)
Skin, Artificial , Animals , Dermis , Epidermal Cells , Epidermis/metabolism , Humans , Keratinocytes/metabolism , Rats
4.
SSM Popul Health ; 15: 100901, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34466652

ABSTRACT

In the absence of adequate social security, out-of-pocket health expenditure compels households to adopt coping strategies, such as utilizing savings, selling assets, or acquiring external financial support (EFS) by borrowing with interest. Households' probability of acquiring EFS and its amount (intensity) depends on its social capital - the nature of social relationships and resources embedded within social networks. This study examines the effect of social capital on the probability and intensity of EFS during health events in Uttar Pradesh (UP), India. The analysis used data from a cross-sectional survey of 6218 households, reporting 3066 healthcare events, from two districts of UP. Household heads (HH) reported demographic, socioeconomic, and health-related information, including EFS, for each household member. Self-reported data from Shortened and Adapted Social Capital Assessment Tool in India (SASCAT-I) was used to generate four unique social capital measures (organizational participation, social support, trust, and social cohesion) at HH and community-level, using multilevel confirmatory factor analysis. After descriptive analysis, two-part mixed-effect models were implemented to estimate the probability and intensity of EFS as a function of social capital measures, where multilevel mixed-effects probit regression was used as the first-part and multilevel mixed-effects linear model with log link and gamma distribution as the second-part. Controlling for all covariates, the probability of acquiring EFS significantly increased (p = 0.04) with higher social support of the HH and significantly decreased (p = 0.02) with higher community social cohesion. Conditional to receiving any EFS, higher social trust of the HH resulted in higher intensity of EFS (p = 0.09). Social support and trust may enable households to cope up with financial stress. However, controlling for the other dimensions of social capital, high cohesiveness with the community might restrict a household's access to external resources demonstrating the unintended effect of social capital exerted by formal or informal social control.

5.
BMJ Open ; 10(6): e037202, 2020 06 30.
Article in English | MEDLINE | ID: mdl-32606063

ABSTRACT

OBJECTIVE: Having the world's second-largest tobacco-consuming population, tobacco control is a priority agenda of the Indian Government. Yet, there is no evidence of how peer influence and nature of social relationships-defined as social capital-affect tobacco use. This study aimed to explore the role of social capital and peer influence on tobacco consumption among household heads in rural Uttar Pradesh (UP), India. DESIGN AND SETTING: This study was embedded within the baseline evaluation of Project Samuday. A cross-sectional multistage cluster survey was implemented in six census blocks of Hardoi and Sitapur districts of UP from June to August 2017. Self-reported tobacco consumption status of randomly selected 6218 household heads (≥18 years; men vs women=5312 vs 906) was assessed from 346 rural communities. Peer influence of tobacco use was measured by the non-self cluster proportion of tobacco consumption among respondents. Community engagement, social support, trust and social cohesion were separately measured as unique facets of social capital both at individual and community levels using the Shortened Adapted Social Capital Assessment Tool in India (SASCAT-I). The explanatory power of covariates was assessed using gender-stratified generalised estimating equations (GEE) with robust-variance estimator. RESULT: Tobacco consumption patterns were starkly different for men and women (71% vs 14%). The peer influence only affected men (adjusted odds ratio (AOR)=1.10, 95% CI: 1.05 to 1.16, p<0.01), whereas women were more likely to consume tobacco if they were more engaged with community organisations (AOR=1.33, 95% CI=1.07 to 1.66, p<0.01). CONCLUSION: Gender alters the way social engagement affects tobacco use in rural India. Countering peer influence on Indian men should be prioritised as a tobacco control strategy. Moreover, as gender mainstreaming is a critical egalitarian agenda in India, further research is needed to understand how social engagement affects tobacco consumption behaviours among women.


Subject(s)
Developing Countries , Family Characteristics , Peer Influence , Rural Population , Smoking/psychology , Social Capital , Adolescent , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , India , Male , Middle Aged , Sex Factors , Smoking/epidemiology , Social Facilitation , Social Support , Young Adult
7.
SSM Popul Health ; 10: 100545, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32405528

ABSTRACT

The National Health Policy (2017) of India advocates Universal Health Coverage through inclusive growth, decentralization, and rebuilding a cohesive community through a participatory process. To achieve this goal, understanding social organization, and community relationships - defined as social capital - is critical. This study aimed to explore the influence of individual and community-level social capital on a critical health system performance indicator, three-doses of diphtheria-pertussis-tetanus (DPT3) immunization among 12-59 month children, in rural Uttar Pradesh (UP), India. The analysis is based on a cross-sectional survey from two districts of UP, which included 2239 children 12-59 months of age (level 1) from 1749 households (level 2) nested within 346 communities (level 3). We used multilevel confirmatory factor analysis to generate standardized factor scores of social capital constructs (Organizational Participation, Social Support, Trust and Social Cohesion) of the household heads and mothers both at individual and community level, which were then used in the multilevel logistic regressions to explore the independent and contextual effect of social capital on a child's DPT3 immunization status. The result showed only community-level Social Cohesion of the mothers was associated with a child's DPT3 immunization status (Adjusted odds ratio = 1.25, 95% confidence interval = 1.12-1.54; p = 0.04). Beyond its independent effect on utilization of immunization service, the collective Social Cohesion of the mothers significantly modified the relationship of child age, mother's knowledge of immunization, community wealth, and communities' contact with frontline workers with immunization status of the child. With a strong theoretical underpinning, the result substantially contributes to understanding the individual and contextual predictors of immunization service utilization and further advancing the literature of social capital in India. This study can serve as a starting point to catalyze social capital within the health interventions for achieving wellbeing and the collective development of society.

8.
Cancer Cell ; 32(3): 342-359.e10, 2017 09 11.
Article in English | MEDLINE | ID: mdl-28898696

ABSTRACT

Concomitant hepatocyte apoptosis and regeneration is a hallmark of chronic liver diseases (CLDs) predisposing to hepatocellular carcinoma (HCC). Here, we mechanistically link caspase-8-dependent apoptosis to HCC development via proliferation- and replication-associated DNA damage. Proliferation-associated replication stress, DNA damage, and genetic instability are detectable in CLDs before any neoplastic changes occur. Accumulated levels of hepatocyte apoptosis determine and predict subsequent hepatocarcinogenesis. Proliferation-associated DNA damage is sensed by a complex comprising caspase-8, FADD, c-FLIP, and a kinase-dependent function of RIPK1. This platform requires a non-apoptotic function of caspase-8, but no caspase-3 or caspase-8 cleavage. It may represent a DNA damage-sensing mechanism in hepatocytes that can act via JNK and subsequent phosphorylation of the histone variant H2AX.


Subject(s)
Carcinogenesis/metabolism , Carcinogenesis/pathology , Caspase 8/metabolism , DNA Damage , Liver Neoplasms/enzymology , Liver Neoplasms/pathology , Animals , Apoptosis , Carcinoma, Hepatocellular/pathology , Cell Proliferation , Cellular Senescence , Chronic Disease , Crosses, Genetic , DNA Repair , Fas-Associated Death Domain Protein/metabolism , Female , Genomic Instability , Hepatectomy , Hepatocytes/pathology , Histones/metabolism , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Liver/metabolism , Liver/pathology , Liver Regeneration , Male , Mice , Myeloid Cell Leukemia Sequence 1 Protein/metabolism , Phosphorylation , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Risk Factors
9.
Cell Stem Cell ; 21(2): 225-240.e5, 2017 08 03.
Article in English | MEDLINE | ID: mdl-28736216

ABSTRACT

Bacterial infection leads to consumption of short-lived innate immune effector cells, which then need to be replenished from hematopoietic stem and progenitor cells (HSPCs). HSPCs express pattern recognition receptors, such as Toll-like receptors (TLRs), and ligation of these receptors induces HSPC mobilization, cytokine production, and myeloid differentiation. The underlying mechanisms involved in pathogen signal transduction in HSCs and the resulting biological consequences remain poorly defined. Here, we show that in vivo lipopolysaccharide (LPS) application induces proliferation of dormant HSCs directly via TLR4 and that sustained LPS exposure impairs HSC self-renewal and competitive repopulation activity. This process is mediated via TLR4-TRIF-ROS-p38, but not MyD88 signaling, and can be inhibited pharmacologically without preventing emergency granulopoiesis. Live Salmonella Typhimurium infection similarly induces proliferative stress in HSCs, in part via TLR4-TRIF signals. Thus, while direct TLR4 activation in HSCs might be beneficial for controlling systemic infection, prolonged TLR4 signaling has detrimental effects and may contribute to inflammation-associated HSPC dysfunction.


Subject(s)
Adaptor Proteins, Vesicular Transport/metabolism , Hematopoietic Stem Cells/metabolism , Immunity, Innate , Salmonella typhimurium/physiology , Signal Transduction , Toll-Like Receptor 4/metabolism , Animals , Cell Proliferation/drug effects , Cell Self Renewal/drug effects , DNA/metabolism , Enzyme Activation/drug effects , Gene Expression Profiling , Hematopoietic Stem Cells/drug effects , Immunity, Innate/drug effects , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred C57BL , Myeloid Differentiation Factor 88/metabolism , Reactive Oxygen Species/metabolism , Salmonella typhimurium/drug effects , Signal Transduction/drug effects , Stress, Physiological/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
10.
Nat Cell Biol ; 18(7): 777-89, 2016 07.
Article in English | MEDLINE | ID: mdl-27323328

ABSTRACT

The cyclin-dependent kinase inhibitor p21(WAF1/CIP1) (p21) is a cell-cycle checkpoint effector and inducer of senescence, regulated by p53. Yet, evidence suggests that p21 could also be oncogenic, through a mechanism that has so far remained obscure. We report that a subset of atypical cancerous cells strongly expressing p21 showed proliferation features. This occurred predominantly in p53-mutant human cancers, suggesting p53-independent upregulation of p21 selectively in more aggressive tumour cells. Multifaceted phenotypic and genomic analyses of p21-inducible, p53-null, cancerous and near-normal cellular models showed that after an initial senescence-like phase, a subpopulation of p21-expressing proliferating cells emerged, featuring increased genomic instability, aggressiveness and chemoresistance. Mechanistically, sustained p21 accumulation inhibited mainly the CRL4-CDT2 ubiquitin ligase, leading to deregulated origin licensing and replication stress. Collectively, our data reveal the tumour-promoting ability of p21 through deregulation of DNA replication licensing machinery-an unorthodox role to be considered in cancer treatment, since p21 responds to various stimuli including some chemotherapy drugs.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21/metabolism , DNA Replication/genetics , Genomic Instability/genetics , Cells, Cultured , Cyclin-Dependent Kinase Inhibitor p21/genetics , Cyclins/genetics , Cyclins/metabolism , Humans , Neoplasms/genetics , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
11.
Nat Commun ; 7: 10660, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26876348

ABSTRACT

Embryonic stem cells (ESCs) represent a transient biological state, where pluripotency is coupled with fast proliferation. ESCs display a constitutively active DNA damage response (DDR), but its molecular determinants have remained elusive. Here we show in cultured ESCs and mouse embryos that H2AX phosphorylation is dependent on Ataxia telangiectasia and Rad3 related (ATR) and is associated with chromatin loading of the ssDNA-binding proteins RPA and RAD51. Single-molecule analysis of replication intermediates reveals massive ssDNA gap accumulation, reduced fork speed and frequent fork reversal. All these marks of replication stress do not impair the mitotic process and are rapidly lost at differentiation onset. Delaying the G1/S transition in ESCs allows formation of 53BP1 nuclear bodies and suppresses ssDNA accumulation, fork slowing and reversal in the following S-phase. Genetic inactivation of fork slowing and reversal leads to chromosomal breakage in unperturbed ESCs. We propose that rapid cell cycle progression makes ESCs dependent on effective replication-coupled mechanisms to protect genome integrity.


Subject(s)
DNA Damage , DNA Replication , DNA, Single-Stranded/metabolism , DNA-Binding Proteins/metabolism , G1 Phase Cell Cycle Checkpoints , G1 Phase , Mouse Embryonic Stem Cells/metabolism , Rad51 Recombinase/metabolism , Animals , Ataxia Telangiectasia Mutated Proteins/metabolism , Blastocyst/metabolism , Blotting, Western , Chromatin/metabolism , Chromosomal Proteins, Non-Histone/metabolism , Electrophoresis, Gel, Pulsed-Field , Flow Cytometry , Histones/metabolism , Mice , Microscopy, Confocal , Microscopy, Electron , Microscopy, Fluorescence , Mitosis , Morula/metabolism , Phosphorylation , Poly(ADP-ribose) Polymerases/metabolism , Replication Protein A/metabolism , Tumor Suppressor p53-Binding Protein 1
12.
PLoS Genet ; 11(7): e1005384, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26181065

ABSTRACT

Genome stability is jeopardized by imbalances of the dNTP pool; such imbalances affect the rate of fork progression. For example, cytidine deaminase (CDA) deficiency leads to an excess of dCTP, slowing the replication fork. We describe here a novel mechanism by which pyrimidine pool disequilibrium compromises the completion of replication and chromosome segregation: the intracellular accumulation of dCTP inhibits PARP-1 activity. CDA deficiency results in incomplete DNA replication when cells enter mitosis, leading to the formation of ultrafine anaphase bridges between sister-chromatids at "difficult-to-replicate" sites such as centromeres and fragile sites. Using molecular combing, electron microscopy and a sensitive assay involving cell imaging to quantify steady-state PAR levels, we found that DNA replication was unsuccessful due to the partial inhibition of basal PARP-1 activity, rather than slower fork speed. The stimulation of PARP-1 activity in CDA-deficient cells restores replication and, thus, chromosome segregation. Moreover, increasing intracellular dCTP levels generates under-replication-induced sister-chromatid bridges as efficiently as PARP-1 knockdown. These results have direct implications for Bloom syndrome (BS), a rare genetic disease combining susceptibility to cancer and genomic instability. BS results from mutation of the BLM gene, encoding BLM, a RecQ 3'-5' DNA helicase, a deficiency of which leads to CDA downregulation. BS cells thus have a CDA defect, resulting in a high frequency of ultrafine anaphase bridges due entirely to dCTP-dependent PARP-1 inhibition and independent of BLM status. Our study describes previously unknown pathological consequences of the distortion of dNTP pools and reveals an unexpected role for PARP-1 in preventing DNA under-replication and chromosome segregation defects.


Subject(s)
Bloom Syndrome/genetics , Cytidine Deaminase/genetics , Poly(ADP-ribose) Polymerases/genetics , Pyrimidines/metabolism , Bloom Syndrome/pathology , Cell Line , Centromere/genetics , Chromosome Fragile Sites/genetics , Chromosome Segregation/genetics , Cytidine Deaminase/deficiency , DNA Replication/genetics , Genomic Instability , Humans , Mitosis/genetics , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/biosynthesis , RecQ Helicases/genetics , Sister Chromatid Exchange/genetics
13.
Mol Cell Biol ; 35(5): 856-65, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25535335

ABSTRACT

Poly(ADP-ribosyl)ation (PAR) has been implicated in various aspects of the cellular response to DNA damage and genome stability. Although 17 human poly(ADP-ribose) polymerase (PARP) genes have been identified, a single poly(ADP-ribosyl) glycohydrolase (PARG) mediates PAR degradation. Here we investigated the role of PARG in the replication of human chromosomes. We show that PARG depletion affects cell proliferation and DNA synthesis, leading to replication-coupled H2AX phosphorylation. Furthermore, PARG depletion or inhibition per se slows down individual replication forks similarly to mild chemotherapeutic treatment. Electron microscopic analysis of replication intermediates reveals marked accumulation of reversed forks and single-stranded DNA (ssDNA) gaps in unperturbed PARG-defective cells. Intriguingly, while we found no physical evidence for chromosomal breakage, PARG-defective cells displayed both ataxia-telangiectasia-mutated (ATM) and ataxia-Rad3-related (ATR) activation, as well as chromatin recruitment of standard double-strand-break-repair factors, such as 53BP1 and RAD51. Overall, these data prove PAR degradation to be essential to promote resumption of replication at endogenous and exogenous lesions, preventing idle recruitment of repair factors to remodeled replication forks. Furthermore, they suggest that fork remodeling and restarting are surprisingly frequent in unperturbed cells and provide a molecular rationale to explore PARG inhibition in cancer chemotherapy.


Subject(s)
Glycoside Hydrolases/metabolism , S Phase , Ataxia Telangiectasia Mutated Proteins/metabolism , Cell Proliferation , Chromatin/metabolism , DNA Damage , DNA Repair , DNA, Single-Stranded , GTPase-Activating Proteins/metabolism , HeLa Cells , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Microscopy, Confocal , Microscopy, Electron , Phenotype , Rad51 Recombinase/metabolism , Tumor Suppressor p53-Binding Protein 1
14.
Mutagenesis ; 23(5): 367-70, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18499649

ABSTRACT

Using single-molecule polymerase chain reaction, the frequency of spontaneous and radiation-induced mutation at an expanded simple tandem repeat (ESTR) locus was studied in DNA samples extracted from sperm and bone marrow of Atm knockout (Atm(+/-)) heterozygous male mice. The frequency of spontaneous mutation in sperm and bone marrow in Atm(+/-) males did not significantly differ from that in wild-type BALB/c mice. Acute exposure to 1 Gy of gamma-rays did not affect ESTR mutation frequency in bone marrow and resulted in similar increases in sperm samples taken from Atm(+/-) and BALB/c males. Taken together, these results suggest that the Atm haploinsufficiency analysed in our study does not affect spontaneous and radiation-induced ESTR mutation frequency in mice.


Subject(s)
Bone Marrow , Cell Cycle Proteins/physiology , DNA Repeat Expansion/genetics , DNA-Binding Proteins/physiology , Germ-Line Mutation , Protein Serine-Threonine Kinases/physiology , Spermatozoa , Tumor Suppressor Proteins/physiology , Animals , Ataxia Telangiectasia Mutated Proteins , Bone Marrow/radiation effects , Cell Cycle Proteins/genetics , DNA Mutational Analysis , DNA-Binding Proteins/genetics , Gamma Rays , Germ Cells/radiation effects , Haploidy , Male , Mice , Mice, Inbred BALB C , Polymerase Chain Reaction , Protein Serine-Threonine Kinases/genetics , Spermatozoa/radiation effects , Tumor Suppressor Proteins/genetics
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