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1.
Soft Matter ; 20(5): 1025-1035, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38197513

RESUMO

Spontaneous formation of a supramolecular metal-organic hydrogel using unsubstituted guanosine as a ligand and Zn2+ ions is reported. Guanosine, in the presence of NaOH, self-assembled into a stable G-quadruplex structure, which underwent crosslinking through Zn2+ ions to afford a stable hydrogel. The gel has been characterized using several spectroscopic as well as microscopic studies. The hydrogel demonstrated excellent stimuli responsiveness towards various chemicals and pH. Furthermore, the gel exhibited intrinsic thixotropic behavior and showed self-healing and injectable properties. The optical properties of the Zn-guanosine metallo-hydrogel suggested a semiconducting nature of the gel, which has been exploited for fabricating a thin film device based on a Schottky diode interface between metal and a semiconductor. The fabricated device shows excellent charge transport characteristics and linear rectifying behavior. The findings are likely to pave the way for newer research in the area of soft electronic devices fabricated using materials synthesized by employing simple biomolecules.

2.
Reprod Domest Anim ; 58(8): 1070-1079, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37254573

RESUMO

The use of antibiotics in semen extenders can contribute to the development of antibiotic resistance. The objective of the study was to evaluate epsilon-polylysine (Ɛ-PL) as a substitute for antibiotics in the buffalo semen extender. For this, 20 semen ejaculates were collected from four Murrah buffalo bulls. Each ejaculate was divided into three equal aliquots and extended into an egg yolk-based semen extender containing either antibiotics (strepto-penicillin) or different concentrations of Ɛ-PL (0.64 and 1.28 g/L) to make the final concentration 80 million sperm/mL and cryopreserved as per the standard procedure. The antibiogram sensitivity test confirmed that Ɛ-PL is an effective antimicrobial against microbes present in buffalo semen ejaculates. Furthermore, the addition of Ɛ-PL in the semen extender significantly reduces the colony forming unit (CFU)/mL in cryopreserved semen equivalent to strepto-penicillin. The sperm motility and kinematic parameters assessed by a computer-assisted sperm analyser showed that Ɛ-PL did not inhibit either sperm motility not kinematic parameters of cryopreserved sperm. The flow-cytometric evaluation of frozen-thawed sperm revealed interesting results. The extender supplemented with Ɛ-PL protected sperm acrosome and mitochondrial membrane potential greater than the extender supplemented with strepto-penicillin. Further, Ɛ-PL reduced significantly the production of superoxide anions from mitochondria during the cryopreservation process. In this way, Ɛ-PL may be a suitable alternative to antibiotics in semen extenders. In conclusion, Ɛ-PL at a concentration of 0.64 g/L acts as an effective antimicrobial as well as antioxidant in semen extender for cryopreservation of buffalo sperm.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Animais , Lisina/farmacologia , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Crioprotetores/farmacologia , Espermatozoides , Criopreservação/veterinária , Criopreservação/métodos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Penicilinas , Búfalos
3.
Trop Anim Health Prod ; 55(5): 313, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37735295

RESUMO

This study was attempted to estimate the genetic parameters of semen quality traits in buffalo bulls. The study data consisted of 10975 ejaculates from 45 Murrah buffalo bulls (aged 24-72 months) used for breeding program during year 2010 to 2020. Semen quality traits (ejaculate volume, concentration of sperm, mass activity, initial and post-thaw motility, number of sperms per ejaculate, motile sperm number and discard rates) were studied. It was observed that average ejaculate volume was 2.82 ± 1.45 mL with mean concentration of 1040.12 ± 523.26 million/mL. Higher heritability was observed for number of sperms per ejaculate, number of motile sperm and sperm concentration. Significant phenotypic correlation was obtained between volume and number of sperms per ejaculate as well as volume and number of motile sperms. Likewise, significant phenotypic correlation was evident between sperm concentration with sperm number per ejaculate. Highest phenotypic correlation was obtained between sperm count per ejaculate and motile sperm count. Estimated genetic trends showed significant change in volume and motile sperm number. In conclusion, this study ascertains that genetic parameters of semen traits can be considered during the selection of buffalo bulls in breeding program.


Assuntos
Bison , Búfalos , Masculino , Animais , Búfalos/genética , Análise do Sêmen/veterinária , Sêmen , Contagem de Espermatozoides/veterinária
4.
J Clin Immunol ; 42(5): 923-934, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35420363

RESUMO

BACKGROUND: Vaccination prevents severe morbidity and mortality from COVID-19 in the general population. The immunogenicity and efficacy of SARS-CoV-2 vaccines in patients with antibody deficiency is poorly understood. OBJECTIVES: COVID-19 in patients with antibody deficiency (COV-AD) is a multi-site UK study that aims to determine the immune response to SARS-CoV-2 infection and vaccination in patients with primary or secondary antibody deficiency, a population that suffers from severe and recurrent infection and does not respond well to vaccination. METHODS: Individuals on immunoglobulin replacement therapy or with an IgG less than 4 g/L receiving antibiotic prophylaxis were recruited from April 2021. Serological and cellular responses were determined using ELISA, live-virus neutralisation and interferon gamma release assays. SARS-CoV-2 infection and clearance were determined by PCR from serial nasopharyngeal swabs. RESULTS: A total of 5.6% (n = 320) of the cohort reported prior SARS-CoV-2 infection, but only 0.3% remained PCR positive on study entry. Seropositivity, following two doses of SARS-CoV-2 vaccination, was 54.8% (n = 168) compared with 100% of healthy controls (n = 205). The magnitude of the antibody response and its neutralising capacity were both significantly reduced compared to controls. Participants vaccinated with the Pfizer/BioNTech vaccine were more likely to be seropositive (65.7% vs. 48.0%, p = 0.03) and have higher antibody levels compared with the AstraZeneca vaccine (IgGAM ratio 3.73 vs. 2.39, p = 0.0003). T cell responses post vaccination was demonstrable in 46.2% of participants and were associated with better antibody responses but there was no difference between the two vaccines. Eleven vaccine-breakthrough infections have occurred to date, 10 of them in recipients of the AstraZeneca vaccine. CONCLUSION: SARS-CoV-2 vaccines demonstrate reduced immunogenicity in patients with antibody deficiency with evidence of vaccine breakthrough infection.


Assuntos
COVID-19 , Doenças da Imunodeficiência Primária , Vacinas Virais , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , SARS-CoV-2
5.
Andrologia ; 54(7): e14431, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35451101

RESUMO

Sperm mitochondrion is one of the major susceptible organelles that get damaged during cryopreservation. The study aimed to minimize mitochondrial dysfunction and oxidative stress during sperm cryopreservation using mitochondria-specific antioxidants. For this, semen was collected from five buffalo bulls (3 ejaculates/bull). The ejaculates were diluted in an low-density lipoprotein-based extender and divided into four equal aliquots. Mitochondria-targeted antioxidant (MitoQ) was added at a final concentration of 0 (control), 0.02, 0.2 and 2 µM separately in each aliquotes and cryopreserved. The addition of MitoQ at a concentration of 0.02 µM improved post-thaw sperm motility, plasma membrane integrity and able to sustain sperm motility for a longer time. To investigate MitoQ's effects on mitochondrial function, we measured mitochondrial membrane potential (MMP) using JC-1 dye, superoxide production using Mitosox assay, and lipid peroxidation by TBARS assay. The supplementation of 0.02 µM MitoQ in the extender prevented the significant reduction of MMP and reduced superoxide production resulting in lower lipid peroxidation of sperm plasma membrane after cryopreservation. Further, we found that a higher concentration of MitoQ decreases MMP and increases mitochondrial superoxide production. In conclusion, MitoQ @ 0.02 µM can alleviate oxidative stress by regulating mitochondrial functionality in spermatozoa during cryopreservation.


Assuntos
Antioxidantes , Preservação do Sêmen , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Búfalos/fisiologia , Criopreservação/métodos , Crioprotetores/farmacologia , Masculino , Mitocôndrias/metabolismo , Análise do Sêmen , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides , Superóxidos/metabolismo
6.
Arch Toxicol ; 95(6): 2007-2018, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33772346

RESUMO

Toxicological studies propose that exposure to carbon black nanoparticles induces organ injuries and inflammatory responses. Besides, current understanding of the molecular mechanisms implies that carbon black nanoparticles (CBNP) exposure induces the production of reactive oxygen species (ROS) causing inflammation, mitochondrial dysfunction or disturbance in calcium homeostasis. However, the precise mechanisms whereby CBNP exert these effects in the lung are still not fully understood. To gain insight into the possible mechanism of CBNP exerted toxicity, human alveolar epithelial cells (A549) were exposed to different concentrations of CBNP and for different timepoints. The reaction of the cells was monitored by the systematic use of cell-based measurements of calcium and ROS, in the presence and absence of calcium (Ca2+) pump inhibitors/chelators and antioxidants. Followed by an in-depth PCR analysis of 84 oxidative stress-related genes. The measurements revealed, as compared to the control, that exposure to CBNP nanoparticles leads to the generation of high ROS levels, as well as a disturbance in calcium homeostasis, which remained primarily unchanged even after 24 h of exposure. Nevertheless, in presence of antioxidants N-acetylcysteine (NAC) and Trolox, ROS formation was considerably reduced without affecting the intracellular calcium concentration. On the other hand, Ca2+ pump inhibitors/chelators, BAPTA (1,2-bis(o-amino phenoxy)ethane-N, N, N', N'-tetraacetic acid) and verapamil not only decreased the Ca2+ overload, but also further decreased the ROS formation, indicating its role in CBNP-induced oxidative stress. Further, a PCR array analysis of A549 cells in presence and absence of the calmodulin (CaM) antagonist W7, indicated toward nine altered oxidative stress-related genes which further confirmed our cytotoxicity results. Obtained data suggested that CBNP exposure elevates calcium ion concentration, which further contributes to oxidative stress, via the calcium-binding protein CaM. Its inhibition with W7 leads to downregulation in gene expression of nine oxidative stress-related genes, which otherwise, as compared to control, show increased gene expression. The results of the study thus confirm that exposure of lung epithelial cells to CBNP leads to oxidative stress; however, the oxidative stress itself is a result of a disturbance in both calcium and ROS homeostasis, and should be considered while searching for a new strategy for prevention of CBNP-induced lung toxicity.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fuligem/toxicidade , Células A549 , Células Epiteliais Alveolares/patologia , Antioxidantes/farmacologia , Cálcio/metabolismo , Calmodulina/metabolismo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Fuligem/administração & dosagem , Fatores de Tempo
7.
Clin Obstet Gynecol ; 64(4): 721-738, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34668886

RESUMO

Combined hormonal contraception (CHC) are short-acting, reversible methods containing both estrogen and progestin. Available CHC methods include combined oral contraceptives, transdermal patches, and vaginal rings. The combined oral contraceptive remains the most commonly used contraceptive method in the United States. The general principles of CHC will be reviewed, including mechanism of action and effectiveness. Unless otherwise stated, these principles apply to all CHCs. When discussing clinical studies and specific considerations related only to pills, patches, or rings, the method(s) will be specified. Words that specify sex are used when discussing studies in which sex was specified.


Assuntos
Anticoncepcionais Orais Hormonais , Progestinas , Anticoncepção , Anticoncepcionais Orais Combinados/efeitos adversos , Estrogênios , Feminino , Contracepção Hormonal , Humanos
8.
Contact Dermatitis ; 84(5): 317-325, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33320367

RESUMO

BACKGROUND: People are exposed to mixtures containing allergens and irritants often causing contact dermatitis. Therefore, regulatory authorities require systematic information on the effects of mixtures on the sensitization threshold. In this study a moderate (cinnamal) and a weak (ethylene glycol dimethacrylate) allergen were combined with irritants covering different mechanisms of action (sodium dodecyl sulfate, salicylic acid, and α-pinene). For a systematic approach, the single substances were initially tested using the KeratinoSens assay. Thereafter, each allergen was combined with noncytotoxic concentrations of the irritants. METHOD: The KeratinoSens assay was applied for the single substances according to OECD (Organisation for Economic Co-operation and Development) Test Guideline 442D. Based on these results, three noncytotoxic concentrations of the irritants were selected and applied simultaneously with 12 concentrations of the allergens to the KeratinoSens cells. Sensitization threshold and cytotoxicity were measured and compared with the individual testing. RESULTS: The combinations of allergens and irritants differed from the effects of the single substances and lowered the sensitization threshold. The quantitative approach allowed a clear description of the changes which varied by factors between 1.1 and 10.3. CONCLUSIONS: Overall, the allergen was the prominent compound in the mixture and its nature appeared to determine the degree of the response.


Assuntos
Alérgenos/farmacologia , Irritantes/farmacologia , Queratinócitos/efeitos dos fármacos , Pele/efeitos dos fármacos , Acroleína/análogos & derivados , Acroleína/farmacologia , Linhagem Celular , Dermatite Alérgica de Contato/diagnóstico , Dermatite Irritante/diagnóstico , Relação Dose-Resposta a Droga , Humanos , Metacrilatos/farmacologia
9.
Andrologia ; 53(8): e14123, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34053099

RESUMO

The present study aimed to compensate dilution effect using additional seminal plasma (SP) in conventional (80 million (M) spermatozoa/ml) dose and low spermatozoa/dose (8M spermatozoa/ml). We also attempted to confirm whether removal of SP before the extension of ejaculates affects post-thaw sperm quality of buffalo semen. For this, semen ejaculates (N = 15) were divided into four groups: control (CON), removal of SP by centrifugation (NSP), resuspension of the centrifuged semen pellet into SP (CEN) and extra supplementation of SP (ESP). All groups were diluted into two different semen doses to 20 and 2M spermatozoa/0.25 ml using tris egg yolk extender and subsequently cryopreserved. We found that neither addition nor removal of SP affected sperm motility, kinematics, longevity, mitochondrial superoxide production and high mitochondrial membrane potential (MMP). Further, the addition or removal of SP was not able to compensate dilution effect in 2M groups resulting in a significantly (p < .05) reduction in sperm motility, kinematics, sperm longevity, membrane integrity, MMP, and an increase production of mitochondrial superoxide. In conclusion, it appears that role of SP in the sperm cryopreservation process is insignificant.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Búfalos , Criopreservação , Crioprotetores , Masculino , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
10.
Med J Armed Forces India ; 77(2): 194-199, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33867637

RESUMO

BACKGROUND: Morphometry has now become a useful adjunct to the diagnostic armamentarium of light, immunofluorescence, and electron microscopy, as it provides a deep insight into quantitative parameters of nephropathies. There has been a limited study on its utility especially in diagnosing pediatric renal diseases. This study is probably the first in India to assess the contribution of this diagnostic modality in pediatric renal disease to the best of authors' knowledge. METHODS: It's a retrospective cross-sectional study covering a period of 05 years at a tertiary care hospital. The study includes 28 cases of pediatric (age till 14 years) nephropathies. The diseases were divided into two groups-nephrotic presentation and nephritic presentation. Glomerular morphometry was performed and mean was calculated for Bowman's capsule area, glomerular capillary tuft area, and Bowman's space area; for the three groups, respectively. Renal parameters serum creatinine, blood urea, 24 h urine protein were studied along with hemoglobin and serum cholesterol for the cases. Data were analyzed using SPSS software, version 25, for one-way ANOVA comparing mean in the three groups. RESULTS: We found a positive and significant correlation between Bowman's capsule area with proteinuria, blood urea, and serum creatinine. There was positive and significant correlation between glomerular capillary tuft area and serum creatinine and Bowman's space area and proteinuria in both the groups. CONCLUSION: Glomerular morphometry may contribute to the diagnosis of some glomerulopathies and the association between glomerular morphometric parameters and laboratory data may promote better understanding of the prognosis of these patients.

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