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1.
Sci Rep ; 14(1): 1720, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243064

RESUMO

Multisystem Inflammatory Syndrome in Children (MIS-C) is a rare manifestation of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) infection that can result in increased morbidity and mortality. Mounting evidence describes sex disparities in the clinical outcomes of coronavirus disease 2019 (COVID-19). However, there is a lack of information on sex-specific differences in immune responses in MIS-C. This study is an observational and cross-sectional study and we wanted to examine immune parameters such as cytokines, chemokines, acute phase proteins (APPs), growth factors, microbial translocation markers (MTMs), complement components and matrix metalloproteinases (MMPs) in MIS-C children, based on sex. Male children were associated with heightened levels of pro-inflammatory cytokines-IFNγ, IL-2, TNFα, IL-1α, IL-1ß, IL-6, IL-12, G-CSF and GM-CSF, chemokines-CCL2, CCL11, CXCL1, CXCL8 and CXCL10, acute phase proteins-α-2M, CRP, growth factors VEGF and TGFα, microbial translocation markers- iFABP, LBP, EndoCAb, complement components-C1q, MBL and C3 and matrix metalloproteinases MMP-8 and MMP-9 compared to female children with MIS-C. These results indicate that the heightened immune response in males is a characteristic feature of MIS-C. These findings might explain the differential disease pathogenesis in males compared to females with MIS-C and facilitate a deeper understanding of this disease.


Assuntos
COVID-19/complicações , Citocinas , SARS-CoV-2 , Criança , Humanos , Masculino , Feminino , Estudos Transversais , Proteínas de Fase Aguda , Síndrome de Resposta Inflamatória Sistêmica , Imunidade , Metaloproteinases da Matriz
2.
JAMA Netw Open ; 6(3): e231713, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36961465

RESUMO

Importance: Multisystem inflammatory syndrome in children (MIS-C) is a severe and unrestrained inflammatory response with multiorgan involvement, which occurs within a few weeks following the resolution of acute SARS-CoV-2 infection. The complement system is a vital part of the innate immune system and plays a role in COVID-19 pathogenesis. Objective: To examine and compare the levels of complement components and regulators along with complement activation products in the different clinical spectrum of children with SARS-CoV-2 and a control group. Design, Setting, and Participants: This cross-sectional study analyzed children with MIS-C admitted to a single hospital in India from June through September 2020. Eligible participants were children who were hospitalized of either sex, aged 1 to 18 years. Data were analyzed August 2022. Measures: Levels of complement components and regulators along with complement activation products in all the groups of children. Mann-Whitney U test and Kruskal-Wallis analysis were used to compare the complement component levels, and Spearman rank correlation analysis was used to describe the association between complement components and laboratory and biochemical parameters. Results: A total 145 children were included (median age, 5 years [range, 1 month-17 years); 84 [58%] male): 44 children with MIS-C, 33 with acute COVID-19 (reverse transcriptase-polymerase chain reaction [RT-PCR] positive), 47 with convalescent COVID-19 (immunoglobulin G-positive non-MIS-C) and 21 children for a control group (both serology and RT-PCR negative). Children with MIS-C and COVID-19 had higher levels of C1q (geometric mean [SD]: MIS-C, 61.5 [18.5] ng/mL; acute COVID-19, 56.9 [18.6] ng/mL; controls, 24.1 [3.3] ng/mL), C2 (MIS-C, 605.8 [219.7] ng/mL; acute COVID-19, 606.4 [167.7] ng/mL; controls, 255.9 [73.3] ng/mL), C3 (MIS-C, 318.2 [70.7] ng/mL; acute COVID-19, 237.7 [61.8] ng/mL; controls, 123.4 [15.7] ng/mL), C4b (MIS-C, 712.4 ng/mL; acute COVID-19, 640.7 ng/mL; controls, 351.5 ng/mL), C5 (MIS-C, 1487 ng/mL; acute COVID-19, 1364 ng/mL; controls, 561.9 ng/mL), C5a, (MIS-C, 2614.0 [336.2] ng/mL; acute COVID-19, 1826.0 [541.0] ng/mL; controls, 462.5 [132.4] ng/mL), C3b/iC3b (MIS-C, 3971.0 [635.1] ng/mL; acute COVID-19, 3702.0 [653.9] ng/mL; controls, 2039.0 [344.5] ng/mL), and factor B (MIS-C, 47.6 [7.8] ng/mL; acute COVID-19, 44.6 [6.3] ng/mL; controls, 27.5 [5.0] ng/mL), factor D (MIS-C, 44.0 [17.2] ng/mL; acute COVID-19, 33.8 [18.4] ng/mL; controls, 21.3 [6.1] ng/mL), and factor H (MIS-C, 53.1 [4.0] ng/mL; acute COVID-19, 50.8 [5.7] ng/mL; controls, 43.6 [3.8] ng/mL) in comparison with convalescent and control children. In addition, children with MIS-C had significantly elevated levels of C3 (318.2 [70.7] ng/mL vs 237.7 [61.8] ng/mL), C5a (2614 [336.2] ng/mL vs 1826 [541.0] ng/mL), and mannose-binding lectin (79.4 [12.4] ng/mL vs 69.6 [14.7] ng/mL) in comparison to children with acute COVID-19. Levels of some of these analytes at admission (ie, pretreatment) were more elevated in children with MIS-C who needed pediatric intensive care unit (PICU) support as compared with those who did not require PICU support, and in children with COVID-19 who developed moderate to severe disease compared with those who developed mild disease. Overall, MIS-C and acute COVID-19 were associated with the hyperactivation of complement components and complement regulators. Conclusions and Relevance: In this cross-sectional study, the complement system was associated with the pathogenesis of MIS-C and COVID-19 in children; complement inhibition could be further explored as a potential treatment option.


Assuntos
COVID-19 , Doenças do Tecido Conjuntivo , Criança , Masculino , Humanos , Pré-Escolar , Feminino , SARS-CoV-2 , Estudos Transversais , Hospitalização , Fatores Imunológicos
4.
Front Med (Lausanne) ; 9: 1050804, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544496

RESUMO

Introduction: Multisystem Inflammatory Syndrome in children (MIS-C) is a serious inflammatory sequela of SARS-CoV2 infection. The pathogenesis of MIS-C is vague and matrix metalloproteinases (MMPs) may have an important role. Matrix metalloproteinases (MMPs) are known drivers of lung pathology in many diseases. Methods: To elucidate the role of MMPs in pathogenesis of pediatric COVID-19, we examined their plasma levels in MIS-C and acute COVID-19 children and compared them to convalescent COVID-19 and children with other common tropical diseases (with overlapping clinical manifestations). Results: Children with MIS-C had elevated levels of MMPs (P < 0.005 statistically significant) in comparison to acute COVID-19, other tropical diseases (Dengue fever, typhoid fever, and scrub typhus fever) and convalescent COVID-19 children. PCA and ROC analysis (sensitivity 84-100% and specificity 80-100%) showed that MMP-8, 12, 13 could help distinguish MIS-C from acute COVID-19 and other tropical diseases with high sensitivity and specificity. Among MIS-C children, elevated levels of MMPs were seen in children requiring intensive care unit admission as compared to children not needing intensive care. Similar findings were noted when children with severe/moderate COVID-19 were compared to children with mild COVID-19. Finally, MMP levels exhibited significant correlation with laboratory parameters, including lymphocyte counts, CRP, D-dimer, Ferritin and Sodium levels. Discussion: Our findings suggest that MMPs play a pivotal role in the pathogenesis of MIS-C and COVID-19 in children and may help distinguish MIS-C from other conditions with overlapping clinical presentation.

5.
PLoS Pathog ; 18(11): e1010915, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36322537

RESUMO

The clinical presentation of MIS-C overlaps with other infectious/non-infectious diseases such as acute COVID-19, Kawasaki disease, acute dengue, enteric fever, and systemic lupus erythematosus. We examined the ex-vivo cellular parameters with the aim of distinguishing MIS-C from other syndromes with overlapping clinical presentations. MIS-C children differed from children with non-MIS-C conditions by having increased numbers of naïve CD8+ T cells, naïve, immature and atypical memory B cells and diminished numbers of transitional memory, stem cell memory, central and effector memory CD4+ and CD8+ T cells, classical, activated memory B and plasma cells and monocyte (intermediate and non-classical) and dendritic cell (plasmacytoid and myeloid) subsets. All of the above alterations were significantly reversed at 6-9 months post-recovery in MIS-C. Thus, MIS-C is characterized by a distinct cellular signature that distinguishes it from other syndromes with overlapping clinical presentations. Trial Registration: ClinicalTrials.gov clinicaltrial.gov. No: NCT04844242.


Assuntos
COVID-19 , Lúpus Eritematoso Sistêmico , Criança , Humanos , Linfócitos T CD8-Positivos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico
6.
Vaccine ; 39(46): 6787-6795, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34656378

RESUMO

PURPOSE: This phase 4, randomized, open-label, multicenter study in healthy Indian infants and toddlers evaluated the safety, tolerability, and immunogenicity of the 13-valent pneumococcal conjugate vaccine (PCV13) formulated in a multidose vial (MDV) or single prefilled syringe (PFS). METHODS: Healthy Indian infants (6 weeks of age) were randomized 1:1 to receive either PCV13-MDV or PCV13-PFS concomitant with routine pediatric vaccines. Subjects received a single dose of either PCV13-MDV or PCV13-PFS as a 4-dose schedule (infant series: 1 dose at 6, 10, and 14 weeks of age; toddler dose: 12 months of age). Safety was assessed, including local reactions, systemic events, and adverse events (AEs). Immunogenicity 1 month after both the infant series and toddler dose was measured by concentrations of serotype-specific immunoglobulin G (IgG) antibodies and opsonophagocytic activity titers. RESULTS: Rates and severities of local reactions and systemic events up to 7 days after each dose of either PCV13-MDV or PCV13-PFS were generally similar, with the majority being of mild or moderate severity. PCV13-MDV had a safety profile comparable with PCV13-PFS; both groups experienced a similar frequency of AEs. PCV13-MDV elicited immune responses comparable with those induced by PCV13-PFS. Clear boosting of immune responses after the PCV13-MDV toddler dose was observed; ≥96% of subjects showed serotype-specific IgG concentrations at or above the defined thresholds 1 month after the PCV13-MDV toddler dose. CONCLUSIONS: PCV13-MDV was safe, well tolerated, and immunogenic in healthy Indian infants and toddlers when coadministered with routine pediatric vaccinations. Safety and immunogenicity of PCV13-MDV was comparable with PCV13-PFS. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov: NCT03548337.


Assuntos
Infecções Pneumocócicas , Anticorpos Antibacterianos , Criança , Método Duplo-Cego , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Lactente , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/efeitos adversos , Vacinação , Vacinas Conjugadas/efeitos adversos
7.
Vaccine ; 39(37): 5313-5317, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34366142

RESUMO

PURPOSE: The 13-valent pneumococcal conjugate vaccine (PCV13) was recently approved in India for the prevention of pneumococcal disease in children aged 6 to 17 years based on global data as well as immunogenicity and safety findings from a phase 3 study. The current phase 4 study in India further evaluated the safety profile of PCV13 in this age group to support the positive benefit-risk profile of PCV13. METHODS: Healthy male and female children aged 6 to 17 years in India were administered a single intramuscular injection of PCV13. Through 7 days after PCV13 administration, local reactions and systemic events were recorded daily by caregivers in an electronic diary. Adverse events (AEs) were collected from the provision of informed consent through 28-42 days postvaccination. RESULTS: One hundred subjects enrolled in and completed the study. After PCV13 vaccination, 73.9% and 57.8% of subjects reported local reactions and systemic events, respectively. The majority of reactogenicity events were mild to moderate in severity, with injection site pain and fatigue the most frequently reported local reaction and systemic event, respectively. Six subjects reported 7 AEs, all of which were considered unrelated to PCV13. One subject reported a serious AE (acute hepatitis), which was considered unrelated to PCV13 and ultimately resolved. No subjects withdrew because of AEs, and there were no deaths. CONCLUSION: PCV13 vaccination was well tolerated with an acceptable safety profile in healthy subjects aged 6 to 17 years in India. This work further supports the safety profile of PCV13 for prevention of pneumococcal disease in this age group in India.


Assuntos
Infecções Pneumocócicas , Criança , Feminino , Humanos , Índia , Consentimento Livre e Esclarecido , Injeções Intramusculares , Masculino , Infecções Pneumocócicas/prevenção & controle , Vacinas Conjugadas/efeitos adversos
8.
Curr Microbiol ; 78(8): 3239-3245, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34223923

RESUMO

Streptococcus pneumoniae is the major cause of childhood pneumonia and related deaths in India. Widespread use of erythromycin for the treatment of pneumonia has led to the emergence of erythromycin resistance. Despite this increase in erythromycin resistance, there are very little data on resistance determinants from India. Hence, we aimed to perform the molecular characterization of erythromycin-resistant invasive pneumococcal isolates in India. In this study, 250 erythromycin-resistant invasive isolates obtained from four Indian hospitals between 2014 and 2019 were included. The isolates were reconfirmed by standard CDC protocols, followed by detection of erm(B), mef(A/E) genes, and screening for mutations in 23S rRNA, ribosomal proteins L4 and L22. Among the 250 erythromycin-resistant isolates, 46% (n = 114) and 35% (n = 87) carried the mef(A/E) gene and erm(B) gene, respectively; both genes were present in 8% (n = 20) of the isolates and 12% (n = 29) of the studied strains did not bear any of them. The major mutations associated with erythromycin resistance in 23S rRNA, such as A2060C, A2061G, and C2613G, were absent. The predominant serotypes were 19F, 14, 23F, 6A, 6B, 19A, and 9V. The major clonal complexes were CC320, followed by CC230 and CC63. The predominant gene was mef(A/E), and most of the serotypes were PCV13 (54%). This study contributes to the baseline understanding of the erythromycin resistance determinants associated with the serotypes and sequence types (ST) of Indian invasive S. pneumoniae.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Humanos , Índia , Testes de Sensibilidade Microbiana , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética
9.
Open Forum Infect Dis ; 8(7): ofab279, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34322566

RESUMO

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a rare manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children that can result in increased morbidity and mortality. The inflammatory underpinnings of MIS-C have not been examined in detail. METHODS: We examined the plasma levels of acute phase proteins and microbial translocation markers in children with MIS-C, children with acute coronavirus disease 2019 (COVID-19) infection, SARS-CoV-2-seropositive children, and controls. RESULTS: MIS-C children exhibited significantly higher levels of C-reactive protein (CRP), alpha2 macroglobulin (α2M), serum amyloid P (SAP), lipopolysaccharide (LPS), sCD14, and LPS binding protein (LBP) and significantly lower levels of haptoglobin (Hp) in comparison with seropositive, control, and/or COVID-19 children. In addition, COVID-19 children exhibited significantly higher levels of most of the above markers in comparison with seropositive and control children. Principal component analysis using a set of these markers could clearly discriminate MIS-C and COVID-19 from seropositive and control children. MIS-C children requiring pediatric intensive care unit admission and COVID-19 children with severe disease had higher levels of CRP, SAP, and/or sCD14 at admission. CONCLUSIONS: Our study describes the role of systemic inflammation and microbial translocation markers in children with MIS-C and COVID-19 and therefore helps in advancing our understanding of the pathogenesis of different presentations of SARS-CoV-2 infection in children.

10.
EBioMedicine ; 66: 103317, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33813138

RESUMO

BACKGROUND: SARS-CoV-2 infection in children can present with varied clinical phenotypes and understanding the pathogenesis is essential, to inform about the clinical trajectory and management. METHODS: We performed a multiplex immune assay analysis and compared the plasma biomarkers of Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 infection (PIMS-TS), acute COVID-19 infection (COVID-19), SARS-CoV-2 seropositive and control children admitted to a tertiary care children's hospital in Chennai, India. Pro-inflammatory cytokines, chemokines and growth factors were correlated with SARS-CoV-2 clinical phenotypes. FINDINGS: PIMS-TS children had significantly elevated levels of cytokines, IFNγ, IL-2, TNFα, IL-1α, IFNα, IFNß, IL-6, IL-15, IL-17A, GM-CSF, IL-10, IL-33 and IL-Ra; elevated chemokines, CCL2, CCL19, CCL20 and CXCL10 and elevated VEGF, Granzyme B and PDL-1 in comparison to COVID-19, seropositive and controls. COVID-19 children had elevated levels of IFNγ, IL-2, TNFα, IL-1α, IFNα, IFNß, IL-6, IL-17A, IL-10, CCL2, CCL5, CCL11, CXCL10 and VEGF in comparison to seropositive and/or controls. Similarly, seropositive children had elevated levels of IFNγ, IL-2, IL-1α, IFNß, IL-17A, IL-10, CCL5 and CXCL10 in comparison to control children. Plasma biomarkers in PIMS-TS and COVID-19 children showed a positive correlation with CRP and a negative correlation with the lymphocyte count and sodium levels. INTERPRETATION: We describe a comprehensive plasma biomarker profile of children with different clinical spectrum of SARS-CoV-2 infection from a low- and middle-income country (LMIC) and observed that PIMS-TS is a distinct and unique immunopathogenic paediatric illness related to SARS-CoV-2 presenting with cytokine storm different from acute COVID-19 infection and other hyperinflammatory conditions.


Assuntos
Biomarcadores/sangue , COVID-19/sangue , Síndrome de Resposta Inflamatória Sistêmica/sangue , Adolescente , Proteína C-Reativa/análise , COVID-19/etiologia , COVID-19/virologia , Teste Sorológico para COVID-19 , Estudos de Casos e Controles , Quimiocinas/sangue , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Índia , Lactente , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Contagem de Linfócitos , Masculino , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Síndrome de Resposta Inflamatória Sistêmica/virologia
11.
Indian J Pediatr ; 88(Suppl 1): 124-130, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33469897

RESUMO

OBJECTIVE: High burden of rotavirus associated diarrhea has been documented among Indian children. The phased introduction of an indigenous rotavirus vaccine 'ROTAVAC' in India's national immunization programme began in 2017. Phase-III trial showed the vaccine to have a low-intussusception-risk profile. However, evaluation of post-licensure trends of intussusception is necessary to assess potential vaccine-associated intussusception risk. This study's objective was to describe the epidemiology of intussusception hospitalizations in children under two years of age in Tamil Nadu and Puducherry following ROTAVAC introduction. METHODS: A cross-sectional surveillance was established in six hospitals in Tamil Nadu and Puducherry. Children under two years of age with intussusception fulfilling Brighton Collaboration's criteria for level 1 diagnostic certainty were enrolled. Patient and disease characteristics were captured using a standardized questionnaire. Descriptive and inferential statistical analyses were performed using Stata Version 13. RESULTS: Overall, 287 cases were enrolled and had a median age of seven months. Frequently presenting symptoms were vomiting (78%), abdominal pain (76%), and blood in stool (71%). Abdominal ultrasonography or radiography confirmed diagnosis in 65% of cases and managed by nonoperative measures. Remaining 35% of cases were diagnosed and managed with surgery. Over 98% of the cases had positive treatment outcomes. Age less than five months (OR = 4.36), and hospitalization at a state government health facility (OR = 5.01) were significant predictors for children to receive surgical management. CONCLUSIONS: The present study documents the epidemiology of intussusceptions immediately after the rollout of rotavirus vaccine in Tamil Nadu and Puducherry. No appreciable increase in intussusception hospitalizations was seen in the study hospitals after vaccine introduction.


Assuntos
Intussuscepção , Infecções por Rotavirus , Vacinas contra Rotavirus , Criança , Estudos Transversais , Hospitalização , Humanos , Índia/epidemiologia , Lactente , Intussuscepção/epidemiologia , Intussuscepção/etiologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/efeitos adversos , Vacinação
13.
N Engl J Med ; 383(20): 1932-1940, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33176083

RESUMO

BACKGROUND: A three-dose, oral rotavirus vaccine (Rotavac) was introduced in the universal immunization program in India in 2016. A prelicensure trial involving 6799 infants was not large enough to detect a small increased risk of intussusception. Postmarketing surveillance data would be useful in assessing whether the risk of intussusception would be similar to the risk seen with different rotavirus vaccines used in other countries. METHODS: We conducted a multicenter, hospital-based, active surveillance study at 27 hospitals in India. Infants meeting the Brighton level 1 criteria of radiologic or surgical confirmation of intussusception were enrolled, and rotavirus vaccination was ascertained by means of vaccination records. The relative incidence (incidence during the risk window vs. all other times) of intussusception among infants 28 to 365 days of age within risk windows of 1 to 7 days, 8 to 21 days, and 1 to 21 days after vaccination was evaluated by means of a self-controlled case-series analysis. For a subgroup of patients, a matched case-control analysis was performed, with matching for age, sex, and location. RESULTS: From April 2016 through June 2019, a total of 970 infants with intussusception were enrolled, and 589 infants who were 28 to 365 days of age were included in the self-controlled case-series analysis. The relative incidence of intussusception after the first dose was 0.83 (95% confidence interval [CI], 0.00 to 3.00) in the 1-to-7-day risk window and 0.35 (95% CI, 0.00 to 1.09) in the 8-to-21-day risk window. Similar results were observed after the second dose (relative incidence, 0.86 [95% CI, 0.20 to 2.15] and 1.23 [95% CI, 0.60 to 2.10] in the respective risk windows) and after the third dose (relative incidence, 1.65 [95% CI, 0.82 to 2.64] and 1.08 [95% CI, 0.69 to 1.73], respectively). No increase in intussusception risk was found in the case-control analysis. CONCLUSIONS: The rotavirus vaccine produced in India that we evaluated was not associated with intussusception in Indian infants. (Funded by the Bill and Melinda Gates Foundation and others.).


Assuntos
Intussuscepção/etiologia , Vacinas contra Rotavirus/efeitos adversos , Administração Oral , Estudos de Casos e Controles , Feminino , Humanos , Imunização Secundária/efeitos adversos , Incidência , Índia/epidemiologia , Lactente , Intussuscepção/epidemiologia , Masculino , Vigilância de Produtos Comercializados , Risco , Infecções por Rotavirus/prevenção & controle , Vacinação , Vacinas Atenuadas/efeitos adversos
14.
J Am Chem Soc ; 142(16): 7606-7617, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32233467

RESUMO

Multicomponent supramolecular copolymerization promises to construct complex nanostructures with emergent properties. However, even with two monomeric components, various possible outcomes such as self-sorted supramolecular homopolymers, a random (statistical) supramolecular copolymer, an alternate supramolecular copolymer, or a complex supramolecular block copolymer can occur, determined by their intermolecular interactions and monomer exchange dynamics and hence structural prediction is extremely challenging. Herein, we target this challenge and demonstrate unprecedented two-component sequence controlled supramolecular copolymerization by manipulating thermodynamic and kinetic routes in the pathway complexity of self-assembly of the constitutive monomers. Extensive molecular dynamics simulations provided useful mechanistic insights into the monomer exchange rates and free energy of interactions between the monomers that dictate the self-assembly pathway and sequence. The fluorescent nature of core-substituted naphthalene diimide monomers has been further utilized to characterize the three sequences via Structured Illumination Microscopy (SIM).

15.
Indian J Med Microbiol ; 37(1): 72-90, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424014

RESUMO

Antimicrobial resistance is on the rise across the globe. Increasing incidence of infections due to carbapenem resistance organisms is becoming difficult to treat, due to the limited availability of therapeutic agents. Very few agents such as colistin, fosfomycin, tigecycline and minocycline are widely used, despite its toxicity. However, with the availability of novel antimicrobials, beta-lactam/beta-lactamase inhibitor-based and non-beta-lactam-based agents could be of great relief. This review covers three important aspects which include (i) current management of carbapenem-resistant infections, (ii) determination of specific types of carbapenemases produced by multidrug-resistant and extensively drug-resistant Gram-negative pathogens and (iii) the currently available novel beta-lactam/beta-lactamase inhibitors and non-beta-lactam-based agents' laboratory findings, clinical outcome and implications.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Farmacorresistência Bacteriana Múltipla/genética , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/genética , Carbapenêmicos/farmacologia , Colistina/farmacologia , Fosfomicina/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Minociclina/farmacologia , Tigeciclina/farmacologia
16.
Methods Mol Biol ; 1577: 35-53, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28963712

RESUMO

Mesenchymal stem cells (MSCs) are derived from Wharton's jelly tissue of the human umbilical cord. Given appropriate culture conditions, these cells can self-renew and differentiate into multiple cell types across the lineages. Among the properties exhibited by these cells, immunomodulation through secretion of trophic factors has been widely exploited in a broad spectrum of preclinical/clinical regenerative applications. Moreover, the extracellular matrix is found to play a major role apart from niche cells in determining stem cell fate including that of MSCs. Therefore, the currently employed technique of two-dimensional culture expansion can alter the inherent properties of naïve MSCs originally residing within the three-dimensional space. This limitation can be overcome to some extent by using native extracellular matrix scaffold culture system which mimics the in situ microenvironment. In this chapter, we have elucidated the protocol for the preparation of a native extracellular matrix scaffold by decellularization of the MSC sheet and thereof culture expansion and characterization of human Wharton's jelly-derived MSCs.


Assuntos
Técnicas de Cultura de Células/métodos , Matriz Extracelular/química , Células-Tronco Mesenquimais/citologia , Alicerces Teciduais/química , Geleia de Wharton/citologia , Diferenciação Celular , Proliferação de Células , Separação Celular/métodos , Células Cultivadas , Humanos , Geleia de Wharton/química
17.
Methods Mol Biol ; 1553: 115-132, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28229411

RESUMO

Mesenchymal stem cells (MSCs) are blossoming as a credible source for regenerative medical applications. The use of fetal MSCs is gaining momentum for therapeutic use. The ease of isolation, enhanced characteristics, and immunomodulation properties renders the utilization of fetal MSCs for numerous clinical applications. In this article, we will demonstrate a step-by-step protocol for isolation of Wharton's jelly MSCs (WJMSCs) from the human umbilical cord matrix, preparation of human platelet lysate, fabricating amniotic membrane scaffold and mice model to study skin regeneration using a combination of MSCs and decellularized amniotic membrane scaffold.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Pele/lesões , Geleia de Wharton/citologia , Cicatrização , Animais , Apoptose , Biomarcadores , Ciclo Celular , Diferenciação Celular , Linhagem da Célula , Separação Celular , Rastreamento de Células , Transformação Celular Neoplásica , Células Cultivadas , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Imunofenotipagem , Camundongos SCID , Fenótipo
18.
Hum Vaccin Immunother ; 13(1): 120-127, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-27629913

RESUMO

Multivalent combination vaccines have reduced the number of injections and therefore improved vaccine acceptance, timeliness of administration and global coverage. The hexavalent diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus/Haemophilus influenzae type b (DTPa-HBV-IPV/Hib; Infanrix hexa™) vaccine, administered according to various schedules, is widely used for the primary vaccination of infants worldwide. In the current publication, we are presenting the immunogenicity and safety of 3 doses of DTPa-HBV-IPV/Hib vaccine when administered to Indian infants. 224 healthy infants (mean age 6.8 weeks) were vaccinated at 6-10-14 weeks (W) of age (n = 112) or 2-4-6 months (M) of age (n = 112). One month after the third vaccine dose, the seroprotection/seropositivity status against diphtheria, pertussis, tetanus, polio, hepatitis B and Hib antigens ranged from 98.6% to 100% in both groups. The vaccine response rate to the pertussis antigens ranged from 97% to 100%. Pain (6-10-14W group: 25.2%; 2-4-6M group: 13.4%) and fever (15.3% and; 15.2%, respectively) were the most frequently reported solicited local and general symptoms. Unsolicited adverse events were reported for 35.7% (6-10-14W group) and 22.3% (2-4-6M group) of subjects. No vaccine related serious adverse events were reported. In conclusion, the hexavalent DTPa-HBV-IPV/Hib vaccine was immunogenic and well tolerated, irrespective of the dosing schedule.


Assuntos
Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Vacina contra Difteria, Tétano e Coqueluche/efeitos adversos , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Vacinas Anti-Haemophilus/efeitos adversos , Vacinas Anti-Haemophilus/imunologia , Vacinas contra Hepatite B/efeitos adversos , Vacinas contra Hepatite B/imunologia , Esquemas de Imunização , Vacina Antipólio de Vírus Inativado/efeitos adversos , Vacina Antipólio de Vírus Inativado/imunologia , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Febre/epidemiologia , Vacinas Anti-Haemophilus/administração & dosagem , Voluntários Saudáveis , Vacinas contra Hepatite B/administração & dosagem , Humanos , Índia , Lactente , Dor/epidemiologia , Vacina Antipólio de Vírus Inativado/administração & dosagem , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/efeitos adversos , Vacinas Combinadas/imunologia
19.
Pak J Pharm Sci ; 27(5): 1295-302, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25176365

RESUMO

Fishery waste and by-products are valuable sources of raw material for recovery of antioxidant and bioactive peptides. Due to the increased demand for protein hydrolysates with antioxidative properties by various sectors of consumable food, health care and pharmaceutical industries, the present study focused in the production of fish protein hydrolysate (FPH) by enzymatic digestion from the backbone of Rastrelliger kanagurta (Indian mackerel) and evaluated its antioxidant potential. The observed results of the degree of hydrolysis suggest that the rapid phase of proteolytic cleavage was occurred in the first 60 minutes of incubation and during this period, the rate of hydrolysis was found to be increased with increasing ratio of enzyme to substrate concentration. The result of the antioxidant properties clearly indicates that the 1, 1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging efficacy of FPH was similar to that of synthetic antioxidants like butylated hydroxyl toluene (BHT). The FPH also exhibited significant reducing power ability and great potential to inhibit lipid peroxidation in equivalence with that of synthetic and natural antioxidants such as BHT and α-tocopherol respectively. The overall findings of the study reveal that, FPH produced by tryptic digestion has considerable amount of bioactive peptides with potent antioxidant properties. The synthesized FPH is a good candidate for further development into a commercial food additive.


Assuntos
Antioxidantes/farmacologia , Perciformes , Hidrolisados de Proteína/farmacologia , Animais , Sequestradores de Radicais Livres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos
20.
Clin Pediatr (Phila) ; 53(6): 561-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24817593

RESUMO

Kawasaki disease (KD) is a common cause of cardiovascular morbidity in young children. No study has attempted to stratify risk factors for coronary artery involvement in Indian children. We attempted to study prospectively the risk factors for coronary involvement in children with KD in a tertiary care hospital between October 2009 and November 2011. The clinical details and investigations for all children admitted with KD were tabulated, and echocardiography was performed; 37 children were admitted with KD; and 8 children (21%) had coronary artery abnormalities. Prolonged fever, wider dispersion of symptoms, and pyuria were significantly associated with the development of coronary lesions. Clinical factors such as wider dispersion of symptoms and prolonged fever along with presence of pyuria can increase the risk of coronary lesions. The presence of these factors may help direct aggressive management and prevent loss of precious time.


Assuntos
Aneurisma Coronário/epidemiologia , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Fatores de Risco
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