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1.
Community Dent Health ; 41(1): 83-88, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38377047

RESUMO

Chronic oral diseases, such as caries and periodontal disease, may, in future, be treated by oral microbiome transplant (OMT) technology. OMT therapy would involve collecting a donor oral microbiome and transplanting into a recipient to either prevent or treat oral diseases linked to a change (i.e., dysbiosis) in the oral microbiome. Given the great promise of this technology, we must consider the ethical and practical implications of how it is developed to maximise its accessibility and affordability. Here, we examine ways that OMT technology might be commercialized in the context of equity and accessibility in both clinical or do-it-yourself settings. We do this while assuming that the technology can be developed for humans in ways that are safe and effective at the individual and population-levels. We highlight the need for OMT therapy to be 1) cost-effective, 2) understood by end users and clinicians, 3) easy to access even in rural or remote communities, and 4) providing donors equitable compensation for their microbiomes. These key elements will only be achieved through partnerships between scientists, clinicians, investors and stakeholders throughout development. Therefore, proper acknowledgement and equitable evaluation of contributions in this team will also be critical to ensuring that this technology can be globally accessed. While OMT is likely to reshape how we prevent or treat oral disease, consciously guiding its development toward equity and accessibility to all people may significantly aid in improving health for those without access to dental care.


Assuntos
Cárie Dentária , Microbiota , Doenças da Boca , Doenças Periodontais , Humanos , Cárie Dentária/prevenção & controle
2.
Community Dent Health ; 41(1): 75-82, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38377042

RESUMO

Advancing oral microbiome research has revealed the association between oral microbiome composition and oral disease. However, much of the research has predominantly focused on comparing health and disease conditions, overlooking the potential dental public health implications. This article examines the evolution of oral microbial research from inception, advancement, and current knowledge of health-associated microbiota. Specifically, we focus on two key aspects: the impact of lifestyle and environmental factors on the oral microbiome and using the oral microbes as a therapeutic modality. The complex interaction of host intrinsic, environmental, and lifestyle factors affects the occurrence and development of the oral microbiota. The article highlights the need for ongoing research that embraces population diversity to promote health equity in oral health research and integrate public health practices into microbiome-based research. The implication of population-level interventions and targeted approaches harnessing the oral microbiome as an intervention, such as oral microbiome transplantation, should be further explored.


Assuntos
Microbiota , Boca , Humanos , Saúde Bucal , Saúde Pública , Promoção da Saúde
3.
Cryo Letters ; 45(1): 36-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38538370

RESUMO

BACKGROUND: Extensive dilution of cattle semen with tris-based extender compromises certain sperm kinetic and functional traits following cryopreservation. OBJECTIVE: To study sperm functions of buffalo bulls under high dilution rates. MATERIALS AND METHODS: Twenty-four ejaculates were harvested twice a week from four buffalo bulls, and diluted to sperm concentrations of 80, 60, 40 and 20 million/mL. Diluted samples were filled in straws, equilibrated at refrigeration temperature for 4 h, and frozen in liquid nitrogen. Frozen sperm samples were thawed for evaluation of kinetic and functional attributes. RESULTS: Compared to 20 million/mL (million/mL) sperm sample, the total motility, progressive motility and rapid motility were reduced (P < 0.05) in 5 million/mL sample. The proportion of live sperm were significantly (P < 0.05) higher in 10, 15 and 20 million/mL samples than in 5 million/mL sample. The percentage of moribund sperm, dead sperm, and sperm with lipid per oxidation increased significantly (P < 0.05) in 5 million/mL sample. CONCLUSION: The reduction of sperm concentrations to < 10 million/mL affects post-thaw Buffalo sperm kinetic and functional attributes.. https://doi.org/10.54680/fr24110110712.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Bovinos , Masculino , Búfalos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Criopreservação/veterinária , Crioprotetores , Espermatozoides , Análise do Sêmen/veterinária
4.
Langmuir ; 39(23): 8109-8119, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37269303

RESUMO

Tuning surface properties of nanoparticles by introducing charge, surface functionalization, or polymer grafting is central to their stability and applications. Here, we show that introducing non-DLVO forces like steric and hydrophobic effects in charged silica nanoparticle suspensions through interaction with a nonionic surfactant brings about interesting modulations in their interparticle interaction and phase behavior. The Ludox TM-40 negatively charged silica suspensions thus exhibit liquid-liquid phase separation driven by the onset of interparticle attraction in the system in the presence of the triblock copolymer Pluronic P123. The observed phase separations are thermoresponsive in nature, as they are associated with lower consolute temperatures and a re-entrant behavior as a function of temperature. The nanoparticle-Pluronic system thus undergoes transformation from one-phase to two-phase and then back to one-phase with monotonic increase in temperature. Evolution of the interparticle interaction in the composite system is investigated by dynamic light scattering (DLS), small angle neutron scattering (SANS), zeta potential, rheological, and fluorescence spectroscopy studies. Zeta potential studies show that the charge interaction in the system is partially mitigated through adsorption of a Pluronic micellar layer on the nanoparticle surfaces. Contrast-matching SANS studies suggest that hydrophobic interactions between the adsorbed micellar layer bring about the onset of interparticle attraction in the system. The results are unique and not reported hitherto in charged silica nanoparticle systems.

5.
J Postgrad Med ; 69(4): 215-220, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37357486

RESUMO

Single parent adoption (SPA) is a relatively new construct worldwide and in India. The Ministry of Women and Child Development, Government of India, has laid down criteria for adoption in general and SPA in particular, in conjunction with the Juvenile Justice Act (Care and Protection of Children), 2015. There is scant literature on this topic of SPA, more so in India, that looks into the various psychological nuances of SPA from a mental health professional's (MHP) perspective. This review paper aims to assess SPA from the perspective of a MHP that will focus on its various legal nuances as well as the psychological connotations attached to it. For this, a search strategy was employed that included a thorough literature search from two databases (PubMed and Google Scholar) with relevant keywords related to the topic. The various legal issues pertaining to SPA in the current scenario, the psychological issues and challenges faced by single parents, the behavioral outcomes of adoptees who are adopted by single parents, and ways to deal with the various obstacles of SPA are discussed.


Assuntos
Saúde Mental , Pais Solteiros , Criança , Humanos , Feminino , Adoção/psicologia , Índia
6.
Cryo Letters ; 44(1): 57-65, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36625876

RESUMO

BACKGROUND: Cryopreservation is an important technique for the long-term storage of semen for artificial insemination (AI). Buffalo spermatozoa are sensitive to cryopreservation procedures because of the presence of a high amount of polyunsaturated fatty acids in the plasma membrane. OBJECTIVE: To study the effect of different concentrations of BHT on the quality of Murrah buffalo bull semen for low-dose cryopreservation. MATERIAL AND METHODS: Semen was collected from four high fertile Murrah buffalo bulls (6 ejaculates each) using an artificial vagina. A total of 24 ejaculates were collected from each bull twice a week using an artificial vagina. Every sample was split into four parts: Control without additives; and three treatments with BHT at 0.5 mM, 1 mM or 2 mM. Semen was cryopreserved at low-dose sperm cryopreservation of 20, 15, 10 and 5 million sperm per aliquot after supplementation of BHT. Semen samples were evaluated for fresh, pre-freeze and post-thaw stages. RESULTS: There was a significant increase (p<0.05) in sperm quality parameters, such as progressive motility (%), viability (%), HOST response (%), acrosome integrity (%) and post-thaw motility, with the addition of 0.5-1 mM BHT. CONCLUSION: The addition of BHT in Murrah buffalo semen improves the low dose cryopreservation quality in a dose-dependent manner. doi.org/10.54680/fr23110110612.


Assuntos
Análise do Sêmen , Preservação do Sêmen , Animais , Feminino , Masculino , Sêmen , Búfalos/fisiologia , Criopreservação/veterinária , Criopreservação/métodos , Hidroxitolueno Butilado/farmacologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Motilidade dos Espermatozoides , Crioprotetores/farmacologia
7.
Cryobiology ; 101: 125-134, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33933431

RESUMO

The present study compared the effect of mitochondria-targeted (Mitoquinone, MitoQ) and untargeted cytosolic antioxidant (Resveratrol, RESV) supplementation on lipid peroxidation (LPO) and in-vitro sperm functions of cryopreserved buffalo bull semen. To optimize additive's concentration, sperm pellet obtained from twenty-four ejaculates was supplemented with different concentrations of MitoQ (20 nM, 100 nM, 200 nM); and RESV (10 µM, 25 µM, 50 µM) against control in the extender. The post-thaw sperm motility, livability, and membrane integrity were higher (P < 0.05) in 200 nM MitoQ and 50 µM RESV than other concentrations used. In another experiment, sperm pellet from thirty-two ejaculates was supplemented with 200 nM MitoQ and 50 µM RESV in the extender. Pre-freeze and post-thaw progressive motility and livability were higher (P < 0.05) in MitoQ (200 nM) than RESV (50 µM) treatment. MitoQ supplementation improved post-thaw membrane integrity (CFDA-PI) higher (P < 0.05) than RESV, however, hypo-osmotic swelling response observed no improvement with RESV treatment. Post-thaw LPO rate was lower (P < 0.05) and Bovine cervical mucus penetration was higher (P < 0.05) in MitoQ than RESV treatment. In post-thaw semen, MitoQ showed higher (P < 0.05) proportion of acrosome intact (FITC-PNA), live non-apoptotic (P < 0.01) sperm with a higher reduction (P < 0.05) in membrane scrambling. MitoQ improved (P < 0.01) proportion of sperm with high Mitochondrial Membrane Potential and low LPO (P < 0.01) than RESV treatment. In conclusion, improvement in post-thaw in-vitro sperm functions and cryo-tolerance was more evident in MitoQ than RESV supplemented buffalo bull semen. Our study provides a better strategy to mitigate oxidative stress by enhancing mitochondrial antioxidant system with targeted antioxidants than cytosolic antioxidant supplementation.


Assuntos
Criopreservação , Preservação do Sêmen , Animais , Antioxidantes/farmacologia , Búfalos , Bovinos , Criopreservação/métodos , Crioprotetores/farmacologia , Masculino , Mitocôndrias , Compostos Organofosforados , Resveratrol/farmacologia , Sêmen , Análise do Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Ubiquinona/análogos & derivados
8.
Community Dent Health ; 37(1): 26-31, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32031346

RESUMO

OBJECTIVES: Identify the determinants of periodontitis in a rural Indian population aged 35-44 years. BASIC RESEARCH DESIGN: Case-control clinical and questionnaire study in a cluster sample of 50 villages. METHODS: A total of 3000 persons were screened for the presence of periodontitis using the CDC case definition in full mouth examination. Equal numbers of cases (604 persons with periodontitis) and controls (604 without periodontitis) were recruited and interviewed with a piloted questionnaire. Univariate and multivariate analysis estimated crude and adjusted odds ratios (aOR) respectively with 95% confidence limits. RESULTS: Six factors were determined by multivariate analysis to predict periodontitis: education less than or equal to twelve years of schooling (aOR=2.51, 95% CI=1.18-5.34), alcohol consumption (aOR= 1.7, 95% CI=1.16-2.49), consuming a non-vegetarian diet (aOR=1.38, 95% CI=1.08-1.76), not drinking milk (aOR=1.7, 95% CI= 1.29-2.24), not using a toothbrush for cleaning of teeth (aOR=2.98, 95% CI =1.71-5.21) and not cleaning teeth at least once a day (aOR=2.13, 95% CI=1.58-2.87). CONCLUSION: Risk factors for periodontitis in a rural Indian population were identified. Further studies should validate these findings and appropriate recommendations should be developed to decrease the prevalence and burden of periodontitis in this population.


Assuntos
Periodontite , População Rural , Adulto , Estudos de Casos e Controles , Estudos Transversais , Humanos , Razão de Chances , Prevalência , Fatores de Risco
9.
Community Dent Health ; 37(1): 12-21, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32031339

RESUMO

OBJECTIVE: To determine whether alcohol consumption is associated with the risk of periodontitis. BASIC RESEARCH DESIGN: Systematic review and meta-analysis of observational studies performed using the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. METHOD: PubMed and Scopus were searched for eligible articles published in English from inception till November 2018. The quality of studies was assessed by the Newcastle Ottawa Scale. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated for the risk of periodontitis associated with highest versus lowest/non-alcohol in a random effects meta-analysis model. Heterogeneity and sensitivity were investigated in meta regression analysis. A funnel plot was used to assess publication bias. RESULTS: Twenty-nine observational studies were included. One study with two separate datasets was considered as two separate studies for analysis. Alcohol consumption was significantly associated with the presence of periodontitis (OR = 1.26, 95% CI= 1.11-1.41). Significant heterogeneity (I2=71%) was present in the overall analysis, primarily attributable to sampling cross-sectional studies (I2=76.6%). A funnel plot and Egger tests (p=0.0001) suggested the presence of publication bias. CONCLUSION: Alcohol consumption was associated with increased occurrence of periodontitis and should be considered as a parameter in periodontal risk assessment. Publication bias should be explored in future studies.


Assuntos
Consumo de Bebidas Alcoólicas , Periodontite , Estudos Transversais , Humanos , Estudos Observacionais como Assunto , Razão de Chances , Medição de Risco
10.
Lupus ; 28(4): 545-554, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30857465

RESUMO

Several studies have demonstrated associations between interleukin-18 polymorphisms and risk of systemic lupus erythematosus in different populations except one of Indian origin. We therefore investigated for the influence of interleukin-18 (-1297T/C, -607A/C, -137G/C; + 105A/C) polymorphisms on genetic susceptibility and clinical expression of the disease in Indian systemic lupus erythematosus patients. A total of 200 systemic lupus erythematosus patients and 201 controls were recruited. Genotyping of interleukin-18 polymorphisms were performed by polymerase chain reaction-restriction fragment length polymorphism. Serum interleukin-18 levels were measured by enzyme-linked immunosorbent assay. Interleukin-18 (-1297T/C; -137G/C) polymorphisms showed significant association with genetic susceptibility to the disease in our systemic lupus erythematosus cohort. Stratification analysis revealed -1297CC and -1297C associated with renal involvement (odds ratio = 3.4, correcting p value = 0.0207), (odds ratio = 2.0, correcting p value = 0.0054) respectively. Additionally, -1297C allele frequency was significantly increased in patients with anti-nucleosome antibody (odds ratio = 2.1, correcting p value = 0.0301). Haplotype analysis showed CC haplotype strongly associated with serositis (odds ratio = 9.1, correcting p values = 0.0009) and neurologic involvement (odds ratio = 9.3, correcting p value = 0.0018). We reported a 2.7-fold increase in serum interleukin-18 levels in patients (511.5 ± 242.3 pg/ml) compared to controls (189.4 ± 80.8 pg/ml) ( p < 0.0001). Furthermore, interleukin-18 levels were positively correlated with disease activity ( r = 0.548, p = 0.0001) and renal involvement in the patients with lupus nephritis ( r = 0.569, p < 0.0001). In summary, interleukin-18 polymorphisms elucidated in this study appear to confer genetic susceptibility to the disease and are associated with renal, serositis and neurologic involvement in Indian systemic lupus erythematosus patients.


Assuntos
Predisposição Genética para Doença , Interleucina-18/genética , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Índia/epidemiologia , Lúpus Eritematoso Sistêmico/sangue , Nefrite Lúpica/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Estatísticas não Paramétricas , Adulto Jovem
12.
Phytother Res ; 31(1): 3-26, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27667670

RESUMO

Nelumbo nucifera, also known as sacred lotus, has primarily been used as food throughout the Asian continent, and its medicinal values have been described in Ayurvedic and Traditional Chinese Medicine. The purpose of this study is to systematically characterize the chemical profiling and pharmacological activities of N. nucifera. Herein, we critically reviewed and analysed the phytochemical and pharmacological reports of N. nucifera. Our search for the keyword 'Nelumbo nucifera pharmacology' in all databases reported in Web of Science yielded 373 results excluding reviews and abstracts in document types. Two hundred and forty-three spectrum natural compounds from different parts of N. nucifera belonging to diverse chemical groups, including alkaloids, flavonoids, glycosides, terpenoids, steroids, fatty acids, proteins, minerals, and vitamins have been reported. In addition, distinct pharmacological activities, mainly against cancer, microbial infection, diabetes, inflammation, atherosclerosis, and obesity, have been associated with crude extracts, fractions, and isolated compounds. This review highlights potential use of neferine, liensinine, isoliensinine, and nuciferine in clinical trials. In depth, mechanism of the potential chemical entities from N. nucifera via structure activity relationship needs to be explored to guarantee the stability and safety for the clinical use. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Medicina Tradicional Chinesa/métodos , Nelumbo/química , Fitoterapia/métodos , Extratos Vegetais/química , Sementes/química , Desenho de Fármacos , Extratos Vegetais/farmacologia
13.
Psychol Med ; 46(8): 1719-33, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26965923

RESUMO

BACKGROUND: Paternal depressive symptoms are associated with children's emotional and behavioural problems, which may be mediated by negative parenting. But there is no research on the influence of paternal depressive symptoms on children's emotion regulation and limited literature investigating fathers' parenting as a mediator in the pathway between paternal depressive symptoms and children's externalizing and internalizing problems. We aimed to investigate the mediating role of father-child conflict (at 3 years) in the association between postnatal paternal depressive symptoms (at 9 months) and children's emotional and behavioural problems (at 7 years) (aim 1). We also examined whether mediation pathways were more pronounced for boys or for girls (aim 2). METHOD: Secondary data analysis was conducted on the Millennium Cohort Study, when children were 9 months, 3 years and 7 years old (n = 3520). Main study variables were measured by self-report questionnaires. Fathers completed the Rutter Scale (depressive symptoms) and the Parent-Child Relationship Questionnaire (father-child conflict), while mothers completed the Strengths and Difficulties Questionnaire and the Social Behaviour Questionnaire (child emotional and behavioural problems, emotion regulation). We used structural equation modelling to estimate direct, indirect and total effects of paternal depressive symptoms on child outcomes, mediated by father-child conflict whilst adjusting for relevant covariates (maternal depressive symptoms, child temperament, marital conflict, and socio-economic factors such as poverty indicator and fathers' education level). Multi-group and interaction analysis was then conducted to determine the differential effect by gender of the association between paternal depressive symptoms on child outcomes via father-child conflict. RESULTS: Father-child conflict mediated the association between paternal depressive symptoms and emotion regulation problems [standardized indirect effect (SIE) 95% confidence interval (CI) -0.03 to -0.01, p < 0.001; standardized total effect (STE) 95% CI -0.05 to -0.01, p < 0.05] (aim 1). Father-child conflict mediated a larger proportion of the effect in boys (SIE 95% CI -0.03 to -0.01, p < 0.001; STE 95% CI -0.05 to 0.00, p = 0.063) than it did in girls (SIE 95% CI -0.02 to -0.01, p < 0.001; STE 95% CI -0.04 to 0.01, p = 0.216) (aim 2). CONCLUSIONS: Father-child conflict may mediate the association between postnatal paternal depressive symptoms and children's emotion regulation problems. Paternal depressive symptoms and father-child conflict resolution may be potential targets in preventative interventions.


Assuntos
Depressão/psicologia , Conflito Familiar , Relações Pai-Filho , Pai/psicologia , Ajustamento Social , Comportamento Social , Criança , Pré-Escolar , Estudos de Coortes , Emoções , Feminino , Humanos , Lactente , Masculino , Poder Familiar , Fatores Sexuais , Inquéritos e Questionários , Reino Unido
14.
J Appl Microbiol ; 121(4): 973-87, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27406903

RESUMO

AIMS: The aim of this study was to isolate and characterize the bioactive compound of Micromonospora auratinigra, HK-10 and its antibacterial inhibitory mechanism. METHODS AND RESULTS: An oily bioactive compound was extracted from HK-10 (GenBank accession no. JN381554) and found to have promising antibacterial activity. The compound was characterized as 2-methylheptylisonicotinate (1) by (1) H, (13) C NMR and mass spectroscopy. Minimum inhibitory concentration (MIC) of this molecule was tested by micro broth dilution method and was found to be 70, 40, 80, 60, 60 and 50 µg for Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Echerichia coli, Pseudomonas aeruginosa and Mycobacterium abscessus respectively. The effects of compound 1 were studied on bacterial membrane structure using scanning electron microscopy. The results indicated a membrane-disrupting mechanism, resulting in the dysfunction of the cytoplasmic membrane structure and cell death of the pathogenic bacterial strains. Kinetics of growth of the test organisms was also analysed and indicated 2-methylheptylisonicotinate 1 as a bactericidal agent. Furthermore, we have studied the binding affinity of 1 towards different membrane proteins of pathogenic bacteria by in silico analysis. CONCLUSIONS: 2-methylheptylisonicotinate was isolated from M. auratinigra, a rare actinobacterial strain possessing antibacterial activity through a membrane-disrupting mechanism, and has MICs similar to standard antibiotic neomycin sulphate. It is the first report about a strain of M. auratinigra, isolated from Indo-Burma biodiversity hotspot of North-east India with new antimicrobial activities. In silico studies have also supported these results performed on various membrane targets of pathogenic bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: The antibacterial potential of M. auratinigra is reported for the first time. The results indicate the possible use of 2-methylheptylisonicotinate as a source of antibacterial agent against dreaded human pathogens.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ácidos Isonicotínicos/isolamento & purificação , Ácidos Isonicotínicos/farmacologia , Micromonospora/química , Microbiologia do Solo , Bactérias/classificação , Humanos , Índia , Cinética , Testes de Sensibilidade Microbiana , Micromonospora/classificação , Micromonospora/ultraestrutura
15.
Heliyon ; 10(7): e28777, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586384

RESUMO

This work reports the structural characteristics, surface morphology, linear and nonlinear optical properties of 110 to 225 nm thick plasma polymerized methyl acrylate (PPMA) thin films. X-ray diffraction analyses confirm the amorphous nature of the films. Field emission scanning electron micrographs of the films display cluster-based surface morphology. Attenuated total reflectance Fourier transform infrared spectroscopy confirms the chemical structural changes in the films. The optical properties were studied based on the absorbance, transmittance, and reflectance spectra measured by an ultraviolet-visible spectrophotometer within the wavelength ranges from 200 to 800 nm. The direct optical band gap and Urbach values are increased from 3.66 to 3.83 eV and 0.28 to 0.45 eV, respectively with increasing film thickness. The extinction coefficient and refractive index were evaluated, and discussed a correlation between the refractive index and the optical bandgap. The real and imaginary dielectric constants, volume/surface energy loss functions and skin depth were deduced. The oscillator energies and parameters were analyzed using the concept of Wemple-DiDomenico and Sellmeier models, respectively for a single oscillator. Static linear refractive index for the studied films exhibits normal dispersion behavior with film thicknesses and satisfied Moss, Ravindra-Gupta, and Herve-Vandamme rules. The linear susceptibility, third-order nonlinear susceptibility and the non-linear refractive index are considerably reduced from 0.20, 29.5 × 10-14 esu, and 5.89 × 10-12 esu with increasing optical band gap energies. The outcomes from the analyses of PPMA demonstrated their potential for usage in electronic, optoelectronic, and non-linear device applications.

16.
Mymensingh Med J ; 33(2): 586-591, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557544

RESUMO

Infertility, affecting 60 to 80 million couples globally, is clinically defined as the inability to conceive after 12 months of unprotected sexual contact. Male factors contribute significantly, comprising 40.0% to 50.0% of infertility cases. While the prevalence ranges from 5.0% to 30.0% in developing countries, the exact global prevalence remains unknown. The study, conducted at CMH and Ibn Sina Hospital, Jashore from October 2020 to September 2023, utilized a cross-sectional approach; examining 4173 samples aged 21 to 41. Exclusion criteria considered known female reproductive abnormalities or medications impacting male fertility. Standardized procedures, in-depth questionnaires and SPSS software version 15.0 were employed, adhering to World Health Organization Guidelines. In a study of 4173 seeking infertility treatment, 63.0% had abnormal semen parameters, with 45.0% aged 31-40 years. Addiction patterns: 76.0% used tobacco, 14.0% reported alcohol and tobacco. Occupations: 43.0% government workers, 41.0% private workers. Marriage duration: 44.0% married 5-10 years, infertility duration: 64.0% less than 6 years. Semen analysis showed 40% with sperm count above 65 million, 46.0% with 60.0-90.0% motile sperm, and 78.0% with sperm morphology below 15.0%. The most prevalent abnormality is asthenozoospermia 59%, with oligozoospermia and azoospermia observed in 31% and 3% of cases, respectively. This study highlights the global complexity of male infertility, emphasizing genetic factors in infertile couples. Addressing sample bias and the lack of national epidemiological data underscores the ongoing need for comprehensive research to advance global infertility diagnosis and treatment.


Assuntos
Infertilidade Masculina , Sementes , Masculino , Humanos , Feminino , Prevalência , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/terapia , Análise do Sêmen , Espermatozoides , Contagem de Espermatozoides
17.
J Chem Phys ; 139(16): 165101, 2013 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-24182082

RESUMO

We study the effects of the shear force on the rupture mechanism on a double stranded DNA. Motivated by recent experiments, we perform the atomistic simulations with explicit solvent to obtain the distributions of extension in hydrogen and covalent bonds below the rupture force. We obtain a significant difference between the atomistic simulations and the existing results in the literature based on the coarse-grained models (theory and simulations). We discuss the possible reasons and improve the coarse-grained model by incorporating the consequences of semi-microscopic details of the nucleotides in its description. The distributions obtained by the modified model (simulations and theoretical) are qualitatively similar to the one obtained using atomistic simulations.


Assuntos
DNA/química , Modelos Moleculares , Conformação de Ácido Nucleico , Ligação de Hidrogênio , Software
18.
Nat Genet ; 20(1): 70-3, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9731535

RESUMO

Schizophrenia is a common disorder characterized by psychotic symptoms; diagnostic criteria have been established. Family, twin and adoption studies suggest that both genetic and environmental factors influence susceptibility (heritability is approximately 71%; ref. 2), however, little is known about the aetiology of schizophrenia. Clinical and family studies suggest aetiological heterogeneity. Previously, we reported that regions on chromosomes 22, 3 and 8 may be associated with susceptibility to schizophrenia, and collaborations provided some support for regions on chromosomes 8 and 22 (refs 9-13). We present here a genome-wide scan for schizophrenia susceptibility loci (SSL) using 452 microsatellite markers on 54 multiplex pedigrees. Non-parametric linkage (NPL) analysis provided significant evidence for an SSL on chromosome 13q32 (NPL score=4.18; P=0.00002), and suggestive evidence for another SSL on chromosome 8p21-22 (NPL=3.64; P=0.0001). Parametric linkage analysis provided additional support for these SSL. Linkage evidence at chromosome 8 is weaker than that at chromosome 13, so it is more probable that chromosome 8 may be a false positive linkage. Additional putative SSL were noted on chromosomes 14q13 (NPL=2.57; P=0.005), 7q11 (NPL=2.50, P=0.007) and 22q11 (NPL=2.42, P=0.009). Verification of suggestive SSL on chromosomes 13q and 8p was attempted in a follow-up sample of 51 multiplex pedigrees. This analysis confirmed the SSL in 13q14-q33 (NPL=2.36, P=0.007) and supported the SSL in 8p22-p21 (NPL=1.95, P=0.023).


Assuntos
Cromossomos Humanos Par 13 , Cromossomos Humanos Par 8 , Esquizofrenia/genética , Adulto , Suscetibilidade a Doenças , Feminino , Genes Dominantes , Ligação Genética , Humanos , Escore Lod , Masculino , Repetições de Microssatélites , Modelos Genéticos
19.
East Asian Arch Psychiatry ; 33(3): 100-103, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37771217

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disorder that affects multiple organs. Neuropsychiatric SLE (NPSLE) can manifest with a multitude of neurological and psychiatric symptoms. Psychosis is a rare NPSLE manifestation that can occur at any phase of the illness; 21% of SLE-related psychosis cases occur at the onset of SLE, but the evidence base for this is lacking. We report a case of acute-onset psychosis in a woman that led to a diagnosis of SLE, which was substantiated by physical evaluation and laboratory assessments. Assessment of acute-onset psychosis requires consideration of all differential diagnoses, especially in the presence of atypical features. This case also underscores the importance of physical examination and laboratory investigations in psychosis.


Assuntos
Lúpus Eritematoso Sistêmico , Vasculite Associada ao Lúpus do Sistema Nervoso Central , Transtornos Psicóticos , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/etiologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/complicações , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico
20.
ACS Appl Mater Interfaces ; 15(33): 39926-39945, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37556210

RESUMO

Various literature studies (Table 6) have reported that dispersion of metal nanoparticles (NPs) on graphitic carbon nitride g-C3N4 (M/CN) has considerably improved the photocatalytic hydrogen yield. It is understood that metal NPs create active sites on the surface of CN and act as a cocatalyst. However, the precise changes induced by different metal NPs on the surface of CN still elude us. Here, we report a thorough understanding and comparison of the morphology, metal-support interactions, interfacial charge transfer kinetics, and band characteristics in different M/CN (M = Pt, Pd, Au, Ag, Cu) correlated with photocatalytic activity. Among all metals, Pt/CN was found to be the best performer both under sunlight and UV-visible irradiation. Under sunlight, maximum H2@ 2.7 mmol/h/g was observed over Pt/CN followed by Pd/CN > Au/CN > Ag/CN > Cu/CN ≈ CN. The present study revealed that among all metals, Pt formed superior interfacial contact with g-C3N4 as compared to other metals. The maximum Schottky barrier height (Φb,Pt) of 0.66 V was observed at Pt/CN followed by Φb,Au/CN (0.46 V) and Φb,Pd/CN (0.05 V). The presence of electron-deficient Pt in Pt-XPS, decrease in the intensity of d-DOS of Pt near the Fermi level in VB-XPS, increase in CB tail states, and cathodic shift in Vfb in MS plots sufficiently confirmed strong metal-support interactions in Pt/CN. Due to the SPR effect, Au and Ag NPs suffered from agglomeration and poor dispersion during photodeposition. Finely dispersed Pt NPs (2-4 nm, 53% dispersion) successfully competed with shallow/deep trap states and drove the photogenerated electrons to active metallic sites in a drastically reduced time period as investigated by femtosecond transient absorption spectroscopy. Typically, an interfacial electron transfer rate, KIET,avg, of 2.5 × 1010 s-1 was observed for Pt/CN, while 0.087 × 1010 s-1 was observed in Au/CN. Band alignment/potentials at M/CN Schottky junctions were derived and most favorable in Pt/CN with CB tail states much above the water reduction potential; however, in the case of Pd, these extend much below the H+/H2 potential and hence behave like deep trap states. Thus, in Pd/CN (τ0 = 4200 ps, 49%) and Ag/CN (3870 ps, 53%), electron deep trapping dominates over charge transfer to active sites. The present study will help in designing futuristic new cocatalyst-photocatalyst systems.

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