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1.
PLoS Pathog ; 19(2): e1011196, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36827451

RESUMO

The Omicron variant of SARS-CoV-2 is capable of infecting unvaccinated, vaccinated and previously-infected individuals due to its ability to evade neutralization by antibodies. With multiple sub-lineages of Omicron emerging in the last 12 months, there is inadequate information on the quantitative antibody response generated upon natural infection with Omicron variant and whether these antibodies offer cross-protection against other sub-lineages of Omicron variant. In this study, we characterized the growth kinetics of Kappa, Delta and Omicron variants of SARS-CoV-2 in Calu-3 cells. Relatively higher amounts infectious virus titers, cytopathic effect and disruption of epithelial barrier functions was observed with Delta variant whereas infection with Omicron sub-lineages led to a more robust induction of interferon pathway, lower level of virus replication and mild effect on epithelial barrier. The replication kinetics of BA.1, BA.2 and BA.2.75 sub-lineages of the Omicron variant were comparable in cell culture and natural infection in a subset of individuals led to a significant increase in binding and neutralizing antibodies to the Delta variant and all the three sub-lineages of Omicron but the level of neutralizing antibodies were lowest against the BA.2.75 variant. Finally, we show that Cu2+, Zn2+ and Fe2+ salts inhibited in vitro RdRp activity but only Cu2+ and Fe2+ inhibited both the Delta and Omicron variants in cell culture. Thus, our results suggest that high levels of interferons induced upon infection with Omicron variant may counter virus replication and spread. Waning neutralizing antibody titers rendered subjects susceptible to infection by Omicron variants and natural Omicron infection elicits neutralizing antibodies that can cross-react with other sub-lineages of Omicron and other variants of concern.


Assuntos
COVID-19 , Humanos , Anticorpos Amplamente Neutralizantes , Cinética , SARS-CoV-2/genética , Anticorpos Neutralizantes , Interferons/genética , Anticorpos Antivirais
2.
Scand J Immunol ; 99(2): e13345, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38441373

RESUMO

COVID-19 disease has plagued the world economy and affected the overall well-being and life of most of the people. Natural infection as well as vaccination leads to the development of an immune response against the pathogen. This involves the production of antibodies, which can neutralize the virus during future challenges. In addition, the development of cellular immune memory with memory B and T cells provides long-lasting protection. The longevity of the immune response has been a subject of intensive research in this field. The extent of immunity conferred by different forms of vaccination or natural infections remained debatable for long. Hence, understanding the effectiveness of these responses among different groups of people can assist government organizations in making informed policy decisions. In this article, based on the publicly available data, we have reviewed the memory response generated by some of the vaccines against SARS-CoV-2 and its variants, particularly B cell memory in different groups of individuals.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Anticorpos , Memória Imunológica
3.
Indian J Med Res ; 159(1): 91-101, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38344919

RESUMO

BACKGROUND OBJECTIVES: The clinical course of COVID-19 and its prognosis are influenced by both viral and host factors. The objectives of this study were to develop a nationwide platform to investigate the molecular epidemiology of SARS-CoV-2 (Severe acute respiratory syndrome Corona virus 2) and correlate the severity and clinical outcomes of COVID-19 with virus variants. METHODS: A nationwide, longitudinal, prospective cohort study was conducted from September 2021 to December 2022 at 14 hospitals across the country that were linked to a viral sequencing laboratory under the Indian SARS-CoV-2 Genomics Consortium. All participants (18 yr and above) who attended the hospital with a suspicion of SARS-CoV-2 infection and tested positive by the reverse transcription-PCR method were included. The participant population consisted of both hospitalized as well as outpatients. Their clinical course and outcomes were studied prospectively. Nasopharyngeal samples collected were subjected to whole genome sequencing to detect SARS-CoV-2 variants. RESULTS: Of the 4972 participants enrolled, 3397 provided samples for viral sequencing and 2723 samples were successfully sequenced. From this, the evolution of virus variants of concern including Omicron subvariants which emerged over time was observed and the same reported here. The mean age of the study participants was 41 yr and overall 49.3 per cent were female. The common symptoms were fever and cough and 32.5 per cent had comorbidities. Infection with the Delta variant evidently increased the risk of severe COVID-19 (adjusted odds ratio: 2.53, 95% confidence interval: 1.52, 4.2), while Omicron was milder independent of vaccination status. The independent risk factors for mortality were age >65 yr, presence of comorbidities and no vaccination. INTERPRETATION CONCLUSIONS: The authors believe that this is a first-of-its-kind study in the country that provides real-time data of virus evolution from a pan-India network of hospitals closely linked to the genome sequencing laboratories. The severity of COVID-19 could be correlated with virus variants with Omicron being the milder variant.


Assuntos
COVID-19 , Feminino , Humanos , Masculino , Progressão da Doença , Hospitais , Estudos Prospectivos , SARS-CoV-2/genética , Adulto , Adolescente , Idoso , Pessoa de Meia-Idade
4.
Int Microbiol ; 26(1): 143-147, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36251128

RESUMO

INTRODUCTION: The present study aimed to investigate the antifungal activity of silver nanoparticles (SNPs) against agents of suspected rhino orbital mucormycosis. METHODS: Thirty-two strains were isolated from endoscopy-guided nasal swab and/or tissue biopsy after debridement/surgery on Sabouraud dextrose agar without cyclohexamide. Antifungal activity was conducted according to Clinical and Laboratory Standards Institute's (CLSI) guidelines, M38-A2. The average size of silver nanoparticle was less than 10 nm. RESULTS: Minimum inhibitory concentration (MIC) of nanoparticles of all strains was in the concentration range of 1-64 µg/ml and minimal fungicidal concentration (MFC) at 16-512 µg/ml. CONCLUSION: The SNPs revealed significant antifungal activity against agents of invasive mycosis.


Assuntos
Nanopartículas Metálicas , Mucormicose , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Prata/farmacologia , Mucormicose/diagnóstico , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Testes de Sensibilidade Microbiana
5.
J Nucl Cardiol ; 30(3): 1147-1157, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36474068

RESUMO

BACKGROUND: Routine use of cardiac sympathetic imaging in HF has been limited by the lower availability/sensitivity of radiotracers. This study was aimed to assess the feasibility of 18F-FDOPA (commonly available PET-radiotracer) in assessment of cardiac autonomic dysfunction. METHODS: Twenty-four controls (46.5 ± 11.1 years, 16men) and 24 patients (43.5 ± 11.0 years, 18men) with diagnosed HF (Framingham-Criteria) underwent cardiac-PET/CT. Region(s) Of Interest were drawn over entire left ventricular myocardium (LV), individual walls, and mediastinum (M). Coefficient of Variation (CV) was calculated from individual wall counts. RESULTS: HF patients had significantly lower myocardial 18F-FDOPA uptake (P < .001, independent t test) than controls [32.4% ± 9.5% global reduction; highest in apex (39.9% ± 7.0%)]. A cut-off of LV/M ≤ 1.68 could differentiate patients from controls with sensitivity and specificity of 100% and 95.8%, respectively. LV/M correlated positively with EF (Pearson coefficient = 0.460, P .031). During follow-up, 3 patients were lost to follow-up, 4 died (survival-20.5 ± 4 months), 2 worsened, and 15 remained stable/showed mild improvement. Patients who worsened/died during follow-up had higher CV than those with stable/improving symptoms [0.16 ± 0.05 vs 0.11 ± 0.05, P value .069 (independent t test); Cox regression P = .084]. CONCLUSION: Myocardial 18F-FDOPA uptake in patients with HF is significantly reduced. Higher reduction is seen in those with lower EF. CV, a maker of regional heterogeneity, is a potential prognostic marker.


Assuntos
Cardiopatias , Insuficiência Cardíaca , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Projetos Piloto , Coração
6.
Indian J Med Res ; 157(6): 509-518, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37322634

RESUMO

Background & objectives: Vaccination and natural infection can both augment the immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but how omicron infection has affected the vaccine-induced and hybrid immunity is not well studied in Indian population. The present study was aimed to assess the durability and change in responses of humoral immunity with age, prior natural infection, vaccine type and duration with a minimum gap of six months post-two doses with either ChAdOx1 nCov-19 or BBV152 prior- and post-emergence of the omicron variant. Methods: A total of 1300 participants were included in this observational study between November 2021 and May 2022. Participants had completed at least six months after vaccination (2 doses) with either ChAdOx1 nCoV-19 or an inactivated whole virus vaccine BBV152. They were grouped according to their age (≤ or ≥60 yr) and prior exposure of SARS-CoV-2 infection. Five hundred and sixteen of these participants were followed up after emergence of the Omicron variant. The main outcome was durability and augmentation of the humoral immune response as determined by anti-receptor-binding domain (RBD) immunoglobulin G (IgG) concentrations, anti-nucleocapsid antibodies and anti-omicron RBD antibodies. Live virus neutralization assay was conducted for neutralizing antibodies against four variants - ancestral, delta and omicron and omicron sublineage BA.5. Results: Before the omicron surge, serum anti-RBD IgG antibodies were detected in 87 per cent participants after a median gap of eight months from the second vaccine dose, with a median titre of 114 [interquartile range (IQR) 32, 302] BAU/ml. The levels increased to 594 (252, 1230) BAU/ml post-omicron surge (P<0.001) with 97 per cent participants having detectable antibodies, although only 40 had symptomatic infection during the omicron surge irrespective of vaccine type and previous history of infection. Those with prior natural infection and vaccination had higher anti-RBD IgG titre at baseline, which increased further [352 (IQR 131, 869) to 816 (IQR 383, 2001) BAU/ml] (P<0.001). The antibody levels remained elevated after a mean time gap of 10 months, although there was a decline of 41 per cent. The geometric mean titre was 452.54, 172.80, 83.1 and 76.99 against the ancestral, delta, omicron and omicron BA.5 variants in the live virus neutralization assay. Interpretation & conclusions: Anti-RBD IgG antibodies were detected in 85 per cent of participants after a median gap of eight months following the second vaccine dose. Omicron infection probably resulted in a substantial proportion of asymptomatic infection in the first four months in our study population and boosted the vaccine-induced humoral immune response, which declined but still remained durable over 10 months.


Assuntos
COVID-19 , Humanos , Lactente , COVID-19/prevenção & controle , Imunidade Humoral , SARS-CoV-2 , ChAdOx1 nCoV-19 , Vacinação , Anticorpos Neutralizantes , Imunoglobulina G , Anticorpos Antivirais
7.
Eur J Pediatr ; 181(2): 513-527, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34379196

RESUMO

This observational study done during April-December 2020 at a tertiary-care hospital in Haryana (India) enrolled 152 SARS-CoV-2-exposed neonates. Among them, 150 neonates had perinatal SARS-CoV-2 exposure and 2 neonates had late postnatal exposure. Stable infant-mother dyads were roomed-in with precautions to support breastfeeding. Nasopharyngeal swabs collected from neonates were tested for SARS-CoV-2 by reverse transcriptase-polymerase chain reaction (RT-PCR) test. There was a high incidence of prematurity (23%), low birth weight (31%), intrauterine fetal distress (16%), perinatal asphyxia (6%), admission to neonatal intensive care unit (24%), and mortality (1.3%) among neonates with perinatal SARS-CoV-2 exposure. In this sub-group, 20 neonates tested positive for SARS-CoV-2 in nasopharyngeal swab sample(s). A recent official publication by the World Health Organization emphasizes that the perinatal SARS-CoV-2-exposed neonates found RT-PCR positive once in upper respiratory (non-sterile) sample must document viral persistence in another non-sterile sample for confirmation of mother-to-child virus transmission. With this approach, only one neonate was confirmed intrapartum transmission. A telephonic follow-up in discharged neonates at 1 month of age or 1 month postexposure recorded them all to be asymptomatic and doing well.Conclusion: Neonates with perinatal SARS-CoV-2 exposure constitute a high-risk group and it is not uncommon to get a positive RT-PCR report in upper respiratory sample(s) from these babies. Majority of them do not demonstrate viral persistence. Clinical outcomes are favorable in breastfed infants roomed-in with their asymptomatic-mild symptomatic SARS-CoV-2-infected mothers following appropriate safety protocols. What is Known: •Neonates with perinatal exposure suffer a high burden of morbidities and mortality. •Still, an uncertainty exists about rooming-in and breastfeeding among neonates born to SARS-CoV-2 positive mothers. What is New: •With the policy of mother-infant rooming-in and supporting breastfeeding, none of the neonate suffered clinical illness compatible with postnatal SARS-CoV-2 transmission and infection. •Around 13% perinatal exposed neonates demonstrated SARS-CoV-2 RNA in nasopharyngeal swab samples but the majority of them did not demonstrate viral persistence.


Assuntos
COVID-19 , Transmissão Vertical de Doenças Infecciosas , Leite Humano , Animais , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Leite Humano/imunologia , Mães , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , RNA Viral , SARS-CoV-2
8.
J Gen Virol ; 102(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33904816

RESUMO

Reactive oxygen species (ROS) are chemically active species which are involved in maintaining cellular and signalling processes at physiological concentrations. Therefore, cellular components that regulate redox balance are likely to play a crucial role in viral life-cycle either as promoters of viral replication or with antiviral functions. Zinc is an essential micronutrient associated with anti-oxidative systems and helps in maintaining a balanced cellular redox state. Here, we show that zinc chelation leads to induction of reactive oxygen species (ROS) in epithelial cells and addition of zinc restores ROS levels to basal state. Addition of ROS (H2O2) inhibited dengue virus (DENV) infection in a dose-dependent manner indicating that oxidative stress has adverse effects on DENV infection. ROS affects early stages of DENV replication as observed by quantitation of positive and negative strand viral RNA. We observed that addition of ROS specifically affected viral titres of positive strand RNA viruses. We further demonstrate that ROS specifically altered SEC31A expression at the ER suggesting a role for SEC31A-mediated pathways in the life-cycle of positive strand RNA viruses and provides an opportunity to identify drug targets regulating oxidative stress responses for antiviral development.


Assuntos
Vírus da Dengue/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Replicação Viral , Zinco/farmacologia , Adolescente , Aedes , Animais , Células CACO-2 , Criança , Pré-Escolar , Chlorocebus aethiops , Cricetinae , Dengue/virologia , Vírus da Dengue/fisiologia , Humanos , Estresse Oxidativo , RNA Viral
9.
Altern Ther Health Med ; 27(S1): 196-203, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33891569

RESUMO

CONTEXT: SARS-CoV-2 is a global public-health concern. Interventions to prevent infection are urgently needed. The anti-inflammatory and antiviral effects of neem make it a potential agent for COVID-19 prophylaxis. OBJECTIVE: The study intended to evaluate the prophylactic effects of neem capsules for persons at high risk of COVID-19 infection due to contact with COVID-19 positive patients. DESIGN: The research team designed a prospective, randomized, double-blind, placebo-controlled, parallel-design study. SETTING: The study was conducted at a single center in India. PARTICIPANTS: Participants were 190 healthcare workers at the hospital or relatives of patients with COVID-19 infection. INTERVENTION: Of the 190 participants, 95 were in the intervention group and 95 in the control group. Participants received 50 mg of a proprietary, patent-pending, neem-leaf extract or a placebo orally in capsules, twice a day for 28 days. OUTCOME MEASURES: The number of individuals positive for COVID-19 between baseline and follow-up on day 56 was the primary outcome measure. Secondary measures included an evaluation of neem's safety and its effects on quality of life (QOL) and changes in biomarkers. RESULTS: The mean age of participants was 36.97 years, and 68.42% were male. Total 13 subjects tested positive during the study. All were asymptomatic. Of the 154 participants who completed the study per-protocol, 11 tested positive, 3 in the intervention group and 8 in the control group. The probability of COVID-19 infection in participants receiving the intervention was 0.45 times that of participants receiving the placebo, a relative risk of 0.45, with the effectiveness of the intervention being around 55%. Treatment-emergent adverse events (TEAEs) in both groups were minimal and were of grade 1 or 2 in severity. Biomarkers and QOL remained stable in both groups. CONCLUSIONS: The study found a reduced risk of COVID-19 infection in participants receiving neem capsules, which demonstrates its potential as a prophylactic treatment for the prevention of COVID-19 infection. The findings warrant further investigation in clinical trials.


Assuntos
Azadirachta , COVID-19 , Adulto , Cápsulas , Método Duplo-Cego , Humanos , Estudos Prospectivos , Qualidade de Vida , SARS-CoV-2 , Resultado do Tratamento
11.
Neurol Sci ; 39(4): 691-698, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29427165

RESUMO

Polymorphisms in MTHFR gene are mostly associated with increased levels of homocysteine in the absence of dietary folate and are a risk factor for complex neurovascular diseases like migraine. The aim of present case-control study was to determine the association between MTHFR gene polymorphisms (C667T; rs 1801133, A1298C; rs 1801131) with migraine susceptibility. In total, 100 patients with migraine (23with MA and 77 with MO) and age-sex matched 100 healthy controls were included in this study from OPD of ESIC Medical College & Hospital, Faridabad. Genotyping was done by PCR-RFLP method. Genotypic and allelic frequencies were compared by SPSS 24 version. Genotypic results indicated a non-significant increase in frequencies of CT and TT in C667T SNP in migraine patients with control (52 and 10% vs. 42 and 7%: p > 0.05), but CC genotype in A1298C was found to be a risk factor in migraine patients than controls (30 vs. 17% respectively: p < 0.05). On comparing migraine subclasses, migraine with aura (MA) and without aura (MO) with control groups, the present study suggests that in MTHFR polymorphisms, the prevalence of 677CT genotype and T allele in C667T SNP influences susceptibility to MA (p < 0.05) but not to MO. Meanwhile, CC genotype in A1298C SNP could be a risk factor for migraine patients without aura (p < 0.05).


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Transtornos de Enxaqueca/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
12.
Indian J Physiol Pharmacol ; 58(2): 162-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25509968

RESUMO

Physical inactivity is a leading risk factor for overweight and obesity in the society. Prevalence of overweight and obesity in the reproductive age group women not only affects maternal health but also the health of the off spring. Infertility is a common problem in India affecting 13-19 million people at any given time. Even though it is not life threatening, infertility causes intense mental agony and trauma that can only be best described by infertile couples themselves. Infertility is more common in overweight and obese individuals compared to normal weight individuals. Decreasing ovarian reserve is an important factor for infertility in women. This study examined the impact of physical activity on ovarian reserve markers in normal, overweight and obese reproductive age women. The observations made in this study reveal that physical activity improves ovarian reserve markers in all reproductive age women but this improvement is more distinct and statistically significant in overweight and obese women compared to normal weight women.


Assuntos
Infertilidade Feminina/fisiopatologia , Atividade Motora , Obesidade/fisiopatologia , Reserva Ovariana , Ovário/fisiopatologia , Sobrepeso/fisiopatologia , Adulto , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Estudos Transversais , Feminino , Hormônio Foliculoestimulante Humano/sangue , Humanos , Infertilidade Feminina/sangue , Infertilidade Feminina/diagnóstico , Obesidade/sangue , Obesidade/diagnóstico , Folículo Ovariano/diagnóstico por imagem , Ovário/diagnóstico por imagem , Sobrepeso/sangue , Sobrepeso/diagnóstico , Fatores de Risco , Comportamento Sedentário , Ultrassonografia , Adulto Jovem
13.
Indian J Physiol Pharmacol ; 58(3): 197-205, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25906601

RESUMO

Normal pregnancy is associated with intense alterations in the maternal cardiovascular system. The aim of the present study was, to assess the influence of normal pregnancy on maternal central aortic pressures, arterial stiffness, and arterial wave reflection using non-invasive PC based cardiovascular risk analysis system (Periscope). The current study was conducted on 137 women with, normotensive, healthy, singleton pregnancies at first trimester (n = 42), second trimester (n = 48), third trimester (n = 47) of pregnancy and 35 age matched non-pregnant controls. There was no significant correlation between the estimated means for age and systolic and diastolic blood pressure. There was progressive and significant increase in BMI as pregnancy progresses (p = 0.0001). Heart rate rose significantly from Pre-pregnant to second and second to third trimesters (P < 0.003). There were no significant changes observed in central aortic diastolic pressure (AoDiaBP) as pregnancy progressed (p = 0.235) however Post Hoc comparisons showed a significant increase in central aortic systolic blood pressure (AoSysBP) and central aortic pulse pressure (AoPP) during first trimester when compared with non pregnant control group (p = 0.039 and 0.048 respectively). There was significant increase in central aortic augmentation pressure (AoAugP) in first trimester compared to non pregnant control group (p = 0.024). All the parameters of central aortic pressures were increased in the first trimester but decreased in the second trimester and again increased in the third trimester of pregnancy. There was a significant drop in Brachial-Ankle Pulse wave Velocity (baPWV) during first trimester of pregnancy compared to non-pregnant control group (p = 0.0001) after that there is a progressive increase in baPWV in second and third trimester of pregnancy. In the third trimester baPWV is increased to more than non-pregnant control group but it was non significant (p = 0.562) however it was significantly higher than first trimester (p = 0.0001). Carotid-femoral Pulse wave velocity (cfPWV) also followed the same sequence as BaPWV but the drop in cfPWV during first trimester was not significant (P = 0.135). All of the variables of hemodynamic and arterial compliance differed between participants with various trimester of pregnancy and non-pregnant control group. A significant up and down changes in Augmentation index (Aix) was observed from control to first, second and third trimester of pregnancy (3.14 to 6.74 to 2.63 to 10.51 respectively, P < 0.0001). To summarize our report show that normal pregnancy is associated with a significant cardiovascular adaptation indicated by alteration in central aortic blood pressure, augmentation index and pulse wave velocity.


Assuntos
Gravidez/fisiologia , Rigidez Vascular , Adulto , Índice Tornozelo-Braço , Pressão Sanguínea , Feminino , Humanos , Trimestres da Gravidez , Análise de Onda de Pulso
14.
Artigo em Inglês | MEDLINE | ID: mdl-38557204

RESUMO

India saw a spike in COVID-19 cases in early 2023, and this wave of infection was attributed to XBB sublineages of SARS-CoV-2 Omicron variant. The impact of XBB wave was significantly shorter with low burden of severe cases or hospitalization as compared with previous SARS-CoV-2 variants of concern. Although a combination of old and new mutations in the spike region of XBB.1.16 variant led to a drastic reduction in the ability of antibodies from prior immunity to neutralize this virus, additional nonspike mutations suggested a possible change in its ability to suppress innate immune responses. In this study, we tested the sensitivity of Delta, BA.2.75, and XBB.1.16 variants to interferon-ß (IFN-ß) treatment and found that XBB.1.16 variant was most sensitive to IFN-ß. We next tested the ability of serum antibodies from healthy individuals to neutralize XBB.1.16. We showed that most of the individuals with hybrid immunity maintained a low but significant level of neutralizing antibodies to XBB.1.16 variant. Therefore, our observations indicated that both hybrid immunity because of natural infection and enhanced sensitivity to IFNs may have contributed to the low impact of XBB.1.16 infections in India.

15.
Nucl Med Commun ; 45(2): 121-127, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982572

RESUMO

OBJECTIVE: F-18 Fluorodeoxyglucose PET/CT (FDG-PET) is emerging as a useful imaging adjunct to MRI in the initial diagnostic evaluation of autoimmune encephalitis (AIE)-though presently it is not included in the diagnostic criteria. MATERIALS AND METHODS: In this prospective study we enrolled a total of 52 patients with clinically diagnosed and treated AIE. MRI evaluation was done in each case along with CSF and EEG where feasible. FDG-PET was done for all and images were interpreted visually and using SPM. RESULTS: The mean age group of patients included was 38.5 ± 22.6 years with 31 females and 21 males. 23 antibody-positive cases underwent PET, the most common antibody detected was anti-NMDAR type followed by anti-LGI 1. Most common metabolic pattern in NMDARE was hypermetabolism in basal ganglia and hypometabolism in parieto-occipital cortices and ovarian teratoma was detected in two of these patients on whole-body PET. A metabolic pattern consistent with AIE was demonstrated in 22/29 (75.8%) antibody-negative patients with hypermetabolism in basal ganglia and mesial temporal cortices. The overall sensitivity of FDG PET was 86% (45/52). MRI abnormalities were detected in 22/52 (42%) cases, 10/23 antibody positive and 12/29 antibody negative cases. PET was positive in 23/30 (76%) MRI negative cases. CONCLUSION: Sensitivity of FDG PET for supporting a diagnosis of AIE was higher compared to MRI in both antibody-positive (definitive) and antibody-negative (presumed) AIE. Specific metabolic patterns can be demonstrated on FDG PET in AIE, prompting an early diagnosis so that timely treatment can be instituted.


Assuntos
Doenças Autoimunes do Sistema Nervoso , Fluordesoxiglucose F18 , Masculino , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Compostos Radiofarmacêuticos , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética
16.
Adv Biol (Weinh) ; 8(1): e2300349, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37786307

RESUMO

Solubilizing extracellular matrix (ECM) materials and transforming them into hydrogels has expanded their potential applications both in vitro and in vivo. In this study, hydrogels are prepared by decellularization of human placental tissue using detergent and enzymes and by the subsequent creation of a homogenized acellular placental tissue powder (P-ECM). A perfusion-based decellularization approach is employed using detergent and enzymes. The P-ECM with and without gamma irradiation is then utilized to prepare P-ECM hydrogels. Physical and biological evaluations are conducted to assess the suitability of the P-ECM hydrogels for biocompatibility. The decellularized tissue has significantly reduced cellular content and retains the major ECM proteins. Increasing the concentration of P-ECM leads to improved mechanical properties of the P-ECM hydrogels. The biocompatibility of the P-ECM hydrogel is demonstrated through cell proliferation and viability assays. Notably, gamma-sterilized P-ECM does not support the formation of a stable hydrogel. Nonetheless, the use of HCl during the digestion process effectively decreases spore growth and bacterial bioburden. The study demonstrates that P-ECM hydrogels exhibit physical and biological attributes conducive to soft tissue reconstruction. These hydrogels establish a favorable microenvironment for cell growth and the need for investigating innovative sterilization methods.


Assuntos
Detergentes , Hidrogéis , Feminino , Gravidez , Humanos , Hidrogéis/farmacologia , Detergentes/metabolismo , Placenta , Matriz Extracelular/metabolismo , Bioensaio
17.
NPJ Vaccines ; 9(1): 3, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167915

RESUMO

Measuring SARS-CoV-2-specific T cell responses is crucial to understanding an individual's immunity to COVID-19. However, high inter- and intra-assay variability make it difficult to define T cells as a correlate of protection against COVID-19. To address this, we performed systematic review and meta-analysis of 495 datasets from 94 original articles evaluating SARS-CoV-2-specific T cell responses using three assays - Activation Induced Marker (AIM), Intracellular Cytokine Staining (ICS), and Enzyme-Linked Immunospot (ELISPOT), and defined each assay's quantitative range. We validated these ranges using samples from 193 SARS-CoV-2-exposed individuals. Although IFNγ ELISPOT was the preferred assay, our experimental validation suggested that it under-represented the SARS-CoV-2-specific T cell repertoire. Our data indicate that a combination of AIM and ICS or FluoroSpot assay would better represent the frequency, polyfunctionality, and compartmentalization of the antigen-specific T cell responses. Taken together, our results contribute to defining the ranges of antigen-specific T cell assays and propose a choice of assay that can be employed to better understand the cellular immune response against viral diseases.

18.
Indian J Physiol Pharmacol ; 57(1): 9-15, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24020093

RESUMO

Increasing female literacy and employment have resulted in a clear rise in the age at which women conceive. As fertility starts to decline with advancing age more and more number of women are facing the problem of infertility and are seeking medical attention to over come this problem. This resulted in more number of women seeking medical help to over come the problem of Infertility. This age related decline in ovarian reserve is not uniform in all women of reproductive age. A number of ovarian reserve tests were developed to overcome this problem. But to date there is no ideal marker for predicting ovarian reserve and pregnancy outcome in assisted reproductive technology program (ART). Recent studies indicate that anti mullein hormone is a promising marker for predicting ovarian reserve and pregnancy out come. The aim of this study was to assess the influence of age on Anti-Mullerian Hormone (AMH) in ART program outcomes. Ninety-three subjects in the age group of 25 to 42 years were recruited to the study. All these subjects underwent controlled ovarian stimulation (COS) and later intracytoplasmic sperm injection (ICSI). Subjects were divided into four groups. AMH levels in positive and negative pregnancy subjects in the above and below 35years age groups were compared. AMH levels were correlated with other ovarian reserve parameters and clinical pregnancy out come in both the age groups. Statistically significant differences were found in AMH levels between positive and negative pregnancy subjects in the age group of 35 and above, but not in the age group below 35 years. There were positive correlations between AMH and other ovarian reserve markers and clinical pregnancy outcome in this age group. AMH and the number of retrieved oocytes (r = 0.784, P < 0.01), Antral Follicle count (AFC) (r = 0.749, P < 0.01) and Mature Oocytes (MII) (r = 0.407, P < 0.01) followed by Grade-I Embryos (r = 0.433, P < 0.01). The current study revealed that AMH levels are better correlated with ovarian reserve and clinical pregnancy out come in subjects aged 35 years and above.


Assuntos
Hormônio Antimülleriano/sangue , Técnicas de Reprodução Assistida , Adulto , Fatores Etários , Estudos Transversais , Feminino , Humanos , Oócitos/fisiologia , Indução da Ovulação , Gravidez , Resultado da Gravidez
19.
Indian J Physiol Pharmacol ; 57(2): 95-103, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24617158

RESUMO

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on Echocardiographic indices of systolic and diastolic left ventricular function. Forty five overweight & obese and 30 normal weight, serving personnel without any other pathological condition were studied. Group I (n = 23) consisted of subjects with normal weight and body mass index (BMI 18.5-22.9 kg/m2), Group II (n = 28) of overweight subjects (BMI 23-24.9 kg/m2) and Group III (n = 24) of obese subjects (BMI > or = 25 kg/m2). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by > or = 2 SD from the normal weight group. Ejection fraction was increased (p = 0.001) in group II and III however fractional shortening was increased significantly in group III (< 0.001). Left ventricular dimensions (EDD & ESD) were increased (P < 0.001, 0.002) but relative wall thickness was unchanged in group II & III. Systolic dysfunction was not observed in any of the obese patients. The deceleration time was increased (P < 0.01) in overweight and obese subjects compared to normal group individuals. No difference was found between obesity subgroups. Subclinical diastolic dysfunction in the form of reduced E/A ratio and increased deceleration time was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function. Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.


Assuntos
Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Função Ventricular Esquerda , Adulto , Índice de Massa Corporal , Diástole/fisiologia , Ecocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , Sístole/fisiologia
20.
Nucl Med Commun ; 44(8): 682-690, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37272279

RESUMO

INTRODUCTION: A DnCNN for image denoising trained with natural images is available in MATLAB. For Tc-99m DMSA images, any loss of clinical details during the denoising process will have serious consequences since denoised image is to be used for diagnosis. The objective of the study was to find whether this pre-trained DnCNN can be used for denoising Tc-99m DMSA images and compare its performance with block matching 3D (BM3D) filter. MATERIALS AND METHODS: Two hundred forty-two Tc-99m DMSA images were denoised using BM3D filter (at sigma = 5, 10, 15, 20, and 25) and DnCNN. The original and denoised images were reviewed by two nuclear medicine physicians and also assessed objectively using the image quality metrics: SSIM, FSIM, MultiSSIM, PIQE, Blur, GCF, and Brightness. Wilcoxon signed-rank test was applied to find the statistically significant difference between the value of image quality metrics of the denoised images and the corresponding original images. RESULTS: Nuclear medicine physicians observed no loss of clinical information in DnCNN denoised image and superior image quality compared to its original and BM3D denoised images. Edges/boundaries of the scar were found to be well preserved, and doubtful scar became obvious in the denoised image. Objective assessment also showed that the quality of DnCNN denoised images was significantly better than that of original images at P -value <0.0001. CONCLUSION: The pre-trained DnCNN available with MATLAB Deep Learning Toolbox can be used for denoising Tc-99m DMSA images, and the performance of DnCNN was found to be superior in comparison with BM3D filter.


Assuntos
Cicatriz , Redes Neurais de Computação , Humanos , Razão Sinal-Ruído , Imageamento Tridimensional/métodos , Ácido Dimercaptossuccínico Tecnécio Tc 99m , Processamento de Imagem Assistida por Computador/métodos
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