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1.
Nano Lett ; 24(1): 458-465, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38148139

RESUMEN

The subvalent silver kernel represents the nascent state of silver cluster formation, yet the growth mechanism has long been elusive. Herein, two silver nanoclusters (Ag30 and Ag34) coprotected by TC4A4- (H4TC4A = p-tert-butylthiacalix[4]arene) and TBPMT- (TBPMTH = 4-tert-butylbenzenemethanethiol) containing 6e and 4e silver kernels are synthesized and characterized. The trimer of the 2e superatom Ag14 kernel in Ag30 is built from a central Ag6 octahedron sandwiched by two orthogonally oriented Ag5 trigonal bipyramids through sharing vertexes, whereas a double-octahedral Ag10 kernel in Ag34 is a dimer of 2e superatoms. They manifest disparate polyhedron fusion growth patterns at the beginning of the silver cluster formation. Their excellent solution stabilities are contributed by the multisite and multidentate coordination fashion of TC4A4- and the special valence electron structures. This work demonstrates the precise control of silver kernel growth by the solvent strategy and lays a foundation for silver nanocluster application in photothermal conversion.

2.
BMC Plant Biol ; 24(1): 510, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844838

RESUMEN

BACKGROUND: Optimum planting date and appropriate fertilizer module are essential facets of chrysanthemum cultivation, to enhance quality yield, and improve soil health. A field-based study was undertaken over multiple growing seasons in 2022 and 2023, where six different planting dates, viz., P1:June 15, P2:June 30, P3:July 15, P4:July 30, P5:August 15 and P6:August 30 and two fertilizer modules, FM1:Jeevamrit @ 30 ml plant-1 and FM2:NPK @ 30 g m-2 were systematically examined using a Randomized Block Design (factorial), replicated thrice. RESULTS: P6 planting resulted in early bud formation (44.03 days) and harvesting stage (90.78 days). Maximum plant height (79.44 cm), plant spread (34.04 cm), cut stem length (68.40 cm), flower diameter (7.83 cm), stem strength (19.38˚), vase life (14.90 days), flowering duration (24.08 days), available soil N (314 kg ha-1), available P (37 kg ha-1), available K (347 kg ha-1), bacterial count (124.87 × 107 cfu g-1 soil), actinomycetes count (60.72 × 102 cfu g-1 soil), fungal count (30.95 × 102 cfu g-1 soil), microbial biomass (48.79 µg g-1 soil), dehydrogenase enzyme (3.64 mg TPF h-1 g-1 soil) and phosphatase enzyme (23.79 mol PNP h-1 g-1 soil) was recorded in P1 planting. Among the fertilization module, minimum days to bud formation (74.94 days) and days to reach the harvesting stage (120.95 days) were recorded with the application of NPK @30 g m-2. However, maximum plant height (60.62 cm), plant spread (23.10 cm), number of cut stems m-2 (43.88), cut stem length (51.34 cm), flower diameter (6.92 cm), stem strength (21.24˚), flowering duration (21.75 days), available soil N (317 kg ha-1), available P (37 kg ha-1) and available K (349 kg ha-1) were also recorded with the application of NPK @300 kg ha-1. Maximum vase life (13.87 days), OC (1.13%), bacterial count (131.65 × 107 cfu g-1 soil), actinomycetes count (60.89 × 102 cfu g-1 soil), fungal count (31.11 × 102 cfu g-1 soil), microbial biomass (51.27 µg g-1 soil), dehydrogenase enzyme (3.77 mg TPF h-1 g-1 soil) and phosphatase enzyme (21.72 mol PNP h-1 g-1 soil) were observed with the application of Jeevamrit @ 30 ml plant-1. CONCLUSION: Early planting (P1) and inorganic fertilization (NPK @ 30 g m-2) resulted in improved yield and soil macronutrient content. The soil microbial population and enzymatic activity were improved with the jeevamrit application. This approach highlights the potential for improved yield and soil health in chrysanthemum cultivation, promoting a more eco-friendly and economically viable agricultural model.


Asunto(s)
Chrysanthemum , Fertilizantes , Microbiología del Suelo , Suelo , Chrysanthemum/crecimiento & desarrollo , Fertilizantes/análisis , Suelo/química , Estaciones del Año , Biomasa
3.
Neuropathology ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409890

RESUMEN

Astroblastoma is an uncommon circumscribed glial tumor mostly involving the cerebral hemisphere. The characteristic molecular alteration is meningioma (disrupted in balanced translocation) 1 (MN1) rearrangement. No definite World Health Organization grade has been assigned as both low- and high-grade tumors are known to occur. Tumors in the spine are extremely rare; to date only three cases have been reported in the literature. A vigilant microscopy and ancillary testing aid in diagnosis when the tumors present in unusual locations, as in our case. The prompt differentiation of this tumor from its mimickers is a mandate as modalities of management are different and not clearly established.

4.
J Am Chem Soc ; 145(36): 19523-19532, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37646485

RESUMEN

Structural transformation of metal nanoclusters (NCs) is of great ongoing interest regarding their synthesis, stability, and reactivity. Although sporadic examples of cluster transformations have been reported, neither the underlying transformation mechanism nor the intermediates are unambiguous. Herein, we have synthesized a flexible 54-nuclei silver cluster (Ag54) by combining soft (tBuC≡C-) and hard (nPrCOO-) ligands. The existence of weakly coordinated nPrCOO- enhances the reactivity of Ag54, thus facilitating the dicarboxylic acid to induce structural transformation. X-ray structural analyses reveal that Ag54 transforms to Ag28 cluster-based 2D networks (Ag28a and Ag28b) induced by H2suc (succinic acid) and H2glu (glutaric acid), whereas with H2pda (2,2'-(1,2-phenylene)diacetic acid), a discrete Ag28 cluster (Ag28c) is isolated. The key intermediate Ag17 that emerges during the self-dissociation of Ag54 was isolated by using cryogenic recrystallization and characterized by X-ray crystallography. The "tandem transformation" mechanism for the structure evolution from Ag54 to Ag28a is established by time-dependent electrospray ionization mass spectrometry (ESI-MS) and UV-vis spectroscopy. In addition, the catalytic activity in the 4-nitrophenol reduction follows the sequence Ag28c > Ag28b > Ag28a > Ag54 due to more bare silver sites on the surface of the Ag28 cluster unit. Our findings not only open new avenues to the synthesis of silver NCs but also shed light on a better understanding of the structural transformation mechanism from one cluster to another or cluster-based metal-organic networks induced by dicarboxylates.

5.
Arch Microbiol ; 205(7): 270, 2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37356030

RESUMEN

Nitrogen metabolism in the genus Citrobacter is very poorly studied despite its several implications in wastewater treatment. In the current study, Citrobacter portucalensis strain AAK_AS5 was assessed for remediation of simulated wastewater supplemented with different inorganic nitrogen sources. Combination of (NH4)2SO4 with KNO3 was the most preferred for achieving high growth density followed by (NH4)2SO4 and KNO3 alone. This was in agreement with highest ammonical nitrogen removal of 92.9% in the presence of combined nitrogen sources and the corresponding nitrate nitrogen removal of 93% in the presence of KNO3. Furthermore, these removal capacities were validated by investigating the uniqueness and the spread of metabolic features through pan-genomic approach that revealed the largest number of unique genes (2097) and accessory genes (705) in strain AAK_AS5. Of the total 44 different types of nitrogen metabolism-related genes, 39 genes were associated with the core genome, while 5 genes such as gltI, nasA, nasR, nrtA, and ntrC uniquely belonged to the accessory genome. Strain AAK_AS5 possessed three major nitrate removal pathways viz., assimilatory and dissimilatory nitrate reduction to ammonia (ANRA & DNRA), and denitrification; however, the absence of nitrification was compensated by ammonia assimilation catalyzed by gene products of the GDH and GS-GOGAT pathways. narGHIJ encoding the respiratory nitrate reductase was commonly identified in all the studied genomes, while genes such as nirK, norB, and nosZ were uniquely present in the strain AAK_AS5 only. A markedly different genetic content and metabolic diversity between the strains reflected their adaptive evolution in the environment thus highlighting the significance of C. portucalensis AAK_AS5 for potential application in nitrogen removal from wastewater.


Asunto(s)
Desnitrificación , Aguas Residuales , Nitratos , Amoníaco , Nitrógeno/metabolismo , Nitrificación , Citrobacter/genética , Citrobacter/metabolismo , Procesos Heterotróficos , Aerobiosis , Nitritos/metabolismo
6.
Curr Microbiol ; 80(2): 81, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36662309

RESUMEN

This study reports the draft genome sequence of Bacillus velezensis strain AAK_S6 as a valuable biocontrol agent with high genetic potential to harbor broad-spectrum secondary metabolite producing capacity. A genome data of 4,430,946 bp were generated with a GC content of 46.4% that comprised a total of 4861 genes including a total of 4757 coding sequences (CDS), 104 rRNAs, 85 tRNAs and 80 pseudo-genes. Based on the overall genome-based relatedness indices (OGRI), the strain AAK_S6 has been reassigned to its correct taxonomic position. The strain shared > 99% OrthoANI, > 98% ANIb, > 99% ANIm, > 0.9900 TETRA, > 93% dDDH and 0.08% GC content difference with model strains B. velezensis FZB42T and B. velezensis NRRL B-41580T thus delineating them as closely related species. The genome was mined for strain-specific secondary metabolites that revealed 20 gene clusters for the biosynthesis of several cyclic lipopeptides, saccharides, polyketides along with bacilysin. Thus, the comparative genome analysis of strain AAK_S6 with members of the genus Bacillus by phylogenomic approach revealed that the genomes were almost similar genetically and contained the core genome for B. velezensis. Genomic data strongly supported that the strain AAK_S6 represented an excellent potential candidate for the production of secondary metabolites that could serve as a basis for developing new biocontrol agents, plant growth promoters, and microbial fertilizers.


Asunto(s)
Bacillus , Genoma Bacteriano , Bacillus/metabolismo , Genómica , Desarrollo de la Planta
7.
Curr Microbiol ; 81(1): 27, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38041739

RESUMEN

Multidrug-resistant tuberculosis (MDR-TB) requires treatment with fluoroquinolone (FLQ) drugs, however, the excessive use of FLQ has led to the rise of extensively drug-resistant TB. In 2019, ~ 20% of total MDR-TB cases were estimated to be resistant to FLQ drugs. In the present study, we developed and evaluated the utility of high-resolution melt curve analysis (HRM) for the rapid detection of FLQ-resistant Mycobacterium tuberculosis for the first time directly from sputum samples. A reference plasmid library was generated for the most frequently observed mutations of gyrA gene and was used to discriminate between mutant and wild-type samples in the FLQ-HRM assay. The developed assay was evaluated on n = 25 MDR M. tuberculosis clinical isolates followed by validation on archived sputum DNA (n = 88) using DNA sequencing as a gold standard. The FLQ-HRM assay showed a 100% sensitivity [95% Confidence Interval (CI): 71.5 to 100] and specificity (95% CI: 39.7 to 100) in smear-positive category, and a sensitivity of 88.9% (95% CI: 77.3 to 95.8) with 84.2% (95% CI: 60.4 to 96.6) specificity in smear-negative category. The assay showed a high level of concordance of ~ 90% (κ = 0.74) with DNA sequencing, however, we were limited by the absence of phenotypic drug susceptibility testing data. In conclusion, HRM is a rapid, cost-effective (INR 150/USD 1.83) and closed-tube method for direct detection of FLQ resistance in sputum samples including direct smear-negative samples.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Antituberculosos/farmacología , Isoniazida/farmacología , Esputo/microbiología , Rifampin/farmacología , Fluoroquinolonas/farmacología , Fluoroquinolonas/uso terapéutico , Pruebas de Sensibilidad Microbiana , Sensibilidad y Especificidad , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
8.
Phytother Res ; 37(9): 4018-4041, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37165686

RESUMEN

Polycystic ovary syndrome (PCOS) is most common in women of reproductive age, giving rise to androgen excess and anovulation, leading to infertility and non-reproductive complications. We explored the ameliorating effect of naringenin in PCOS using the Sprague Dawley (SD) rat model and human granulosa cells. Letrozole-induced PCOS rats were given either naringenin (50 mg/kg/day) alone or in combination with metformin (300 mg/kg/day), followed by the estrous cycle, hormonal analysis, and glucose sensitivity test. To evaluate the effect of naringenin on granulosa cell (hGC) steroidogenesis, we treated cells with naringenin (2.5 µM) alone or in combination with metformin (1 mM) in the presence of forskolin (10 µM). To determine the steroidogenesis of CYP-17A1, -19A1, and 3ßHSD2, the protein expression levels were examined. Treatment with naringenin in the PCOS animal groups increased ovulation potential and decreased cystic follicles and levels of androgens. The expression levels of CYP-17A1, -19A1, and 3ßHSD2, were seen restored in the ovary of PCOS SD rats' model and in the human ovarian cells in response to the naringenin. We found an increased expression level of phosphorylated-AKT in the ovary and hGCs by naringenin. Naringenin improves ovulation and suppress androgens and cystic follicles, involving AKT activation.


Asunto(s)
Quiste Folicular , Metformina , Síndrome del Ovario Poliquístico , Humanos , Femenino , Ratas , Animales , Andrógenos/efectos adversos , Ratas Sprague-Dawley , Letrozol/efectos adversos , Proteínas Proto-Oncogénicas c-akt , Quiste Folicular/complicaciones , Modelos Animales de Enfermedad
9.
Int J Neurosci ; 133(6): 642-647, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34275423

RESUMEN

Rosette-forming glioneuronal tumor (RGNT) of the 4th ventricle is a newly described WHO grade I brain tumor included in recent WHO classification of CNS tumors. It is a biphasic tumor thought to originate from pluripotent progenitor cells of subependymal plate. Intra-operative diagnosis plays an important role, as complete surgical excision is the treatment of choice. We are reporting a case of RGNT in a 19 years-old young male emphasizing the intra-operative pathological pointers and their role in accurate diagnosis for the suitable surgical intervention.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Ventrículo Cerebral , Masculino , Humanos , Adulto Joven , Adulto , Neoplasias del Ventrículo Cerebral/diagnóstico por imagen , Neoplasias del Ventrículo Cerebral/cirugía , Cuarto Ventrículo/diagnóstico por imagen , Cuarto Ventrículo/cirugía , Cuarto Ventrículo/patología , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Técnicas Citológicas , Formación de Roseta
10.
Natl Med J India ; 36(1): 36-39, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37615139

RESUMEN

Background The medical curriculum for undergraduates was revised by the Medical Council of India in 2019, after 21 years. We did this study to determine teachers' pedagogical and technical readiness to implement the competency-based curriculum in medical colleges and determine factors that affect readiness, from their perspective. Methods We conducted a cross-sectional survey in the form of an online questionnaire. The qualitative data were coded numerically and were analysed using frequencies and proportions. Pearson Chi-square test was used to study the association among variables. Results The majority (85%) of respondents had attended a curriculum implementation training programme; 62.2% with experience <5 years, 56.1% with experience 5-10 years and a minority of 13.3% with >10 years' experience were ready to a 'great extent' to implement the new curriculum; 54.1% agreed to re-frame lectures and 64.9% possessed technological skills to suit the needs of a competency-based curriculum. About 77% agreed that it will provide a rich learning environment, inspire self-directed learning while 52% believed it will promote scientific thinking and provide better learning outcomes in the long run. Conclusion Medical teachers had a positive attitude towards implementation of the new curriculum. However, numerous factors such as low teacher-student ratio, textbooks designed according to the traditional curriculum, limited teachers' training and cumbersome paperwork may hinder its successful implementation. Updation of teachers' knowledge and skills through seminars/workshops is recommended to facilitate delivery of the new curriculum. Like any other ongoing reforms in medical education, competency-based curriculum is a work in process.


Asunto(s)
Educación Médica , Docentes Médicos , Humanos , Estudios Transversales , Curriculum , Aprendizaje
11.
J Food Sci Technol ; 60(8): 2105-2120, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37273559

RESUMEN

Edible insects (EI) are also becoming as a part of the diet due to their nutritional value and health benefits in many regions of the world. These EI are inexhaustible sources accessible by garnering from the wild with high feed conversion efficiency. Appreciating the budding of EI in justifiable food production, enlightening food security and biodiversity conversion, is promising a sufficient supply of the insect resource for future food to the world. These insects are processed to develop new products, improve organoleptic and nutritional parameters as well as the extension of shelf life. In this review, we discuss the edible insect characteristics, the potential application of EI in food industry, processing, pretreatments, drying, extraction of edible compounds like protein, lipid and chitin various food products formulation, safety regulation. Availability of broad nutritional spectrum of EI includes protein, mono and poly unsaturaturated fatty acids, amino acids, vitamins, amino aids and minerals has been used as an ingredient in development of various forms of food products such as flours in the form of whole insect powder, protein isolate, canned products, extruded products, hard candies, spreads, liquor infusion, cookies and other products.

12.
NMR Biomed ; 35(5): e4665, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34962326

RESUMEN

Magnetic resonance imaging (MRI) is playing an important role in the classification of breast tumors. MRI can be used to obtain multiparametric (mp) information, such as structural, hemodynamic, and physiological information. Quantitative analysis of mp-MRI data has shown potential in improving the accuracy of breast tumor classification. In general, a large set of quantitative and texture features can be generated depending upon the type of methodology used. A suitable combination of selected quantitative and texture features can further improve the accuracy of tumor classification. Machine learning (ML) classifiers based upon features derived from MRI data have shown potential in tumor classification. There is a need for further research studies on selecting an appropriate combination of features and evaluating the performance of different ML classifiers for accurate classification of breast tumors. The objective of the current study was to develop and optimize an ML framework based upon mp-MRI features for the characterization of breast tumors (malignant vs. benign and low- vs. high-grade). This study included the breast mp-MRI data of 60 female patients with histopathology results. A total of 128 features were extracted from the mp-MRI tumor data followed by features selection. Five ML classifiers were evaluated for tumor classification using 10-fold crossvalidation with 10 repetitions. The support vector machine (SVM) classifier based on optimum features selected using a wrapper method with an adaptive boosting (AdaBoost) technique provided the highest sensitivity (0.96 ± 0.03), specificity (0.92 ± 0.09), and accuracy (94% ± 2.91%) in the classification of malignant versus benign tumors. This method also provided the highest sensitivity (0.94 ± 0.07), specificity (0.80 ± 0.05), and accuracy (90% ± 5.48%) in the classification of low- versus high-grade tumors. These findings suggest that the SVM classifier outperformed other ML methods in the binary classification of breast tumors.


Asunto(s)
Neoplasias de la Mama , Imágenes de Resonancia Magnética Multiparamétrica , Mama , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Máquina de Vectores de Soporte
13.
BMC Gastroenterol ; 22(1): 303, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35729511

RESUMEN

BACKGROUND: The aim of this study is to explore the treatment strategies being followed for patients with obstructing colorectal cancer (OCRC) at our institute and to know the management outcomes. METHODS: This study included 28 patients who were diagnosed with obstructing colorectal cancer (OCRC) either preoperatively or intraoperatively over a period of 5 years. RESULTS: Most were in the younger age group with mean age of 49.78 ± 15.96 years with 1/4th of the patients being younger than 40. There was no difference in incidence of OCRC among genders. It was found to be common in rural areas of the eastern Nepal, 16(57%) patients from such areas. 21.4% patients had complete bowel obstruction at presentation. The investigating modalities used were abdominal X-ray, ultrasonoghraphy of abdomen/pelvis, abdominal CT-scan, colonoscopy, serum CEA, punch biopsy and Faecal occult blood test. The anatomical shift to the right was observed with 54% lesions in the proximal colon. Majority were in advanced stage (stage 3:53.6%, stage 4:32.1%) with histologically adenocarcinoma (100%) and a higher incidence of synchronous lesion (28.6%). Patients averaged 13.82 days in the hospital with post-operative mortality rate of 3.6%. The 1-year and 2-years disease free survivals were 89.3% and 82.1% while overall survivals were 92.8% and 82.1% respectively. CONCLUSION: In developing countries like ours, relatively younger patients present to health center with obstructive colorectal cancer with anatomical shift to the right sided lesions. The treatments provided at our center and their outcomes are not inferior to that of the developed world.


Asunto(s)
Neoplasias Colorrectales , Obstrucción Intestinal , Adulto , Anciano , Neoplasias Colorrectales/patología , Femenino , Humanos , Obstrucción Intestinal/epidemiología , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Masculino , Persona de Mediana Edad , Nepal/epidemiología , Estudios Retrospectivos , Centros de Atención Terciaria
14.
Neuroradiology ; 64(9): 1801-1818, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35435463

RESUMEN

PURPOSE: Primary objective of this study was to retrospectively evaluate the potential of a range of qualitative and quantitative multiparametric features assessed on T2, post-contrast T1, DWI, DCE-MRI, and susceptibility-weighted-imaging (SWI) in differentiating evenly sampled cohort of primary-central-nervous-system-lymphoma (PCNSL) vs glioblastoma (GB) with pathological validation. METHODS: The study included MRI-data of histopathologically confirmed ninety-five GB and PCNSL patients scanned at 3.0 T MRI. A total of six qualitative features (three from T2 and post-contrast T1, three from SWI: thin-linear-uninterrupted-intra-tumoral-vasculature, broken-intra-tumoral-microvasculature, hemorrhage) were analyzed by three independent radiologists. Ten quantitative features from DWI and DCE-MRI were computed using in-house-developed algorithms. For qualitative features, Cohen's Kappa-interrater-variability-analysis was performed. Z-test and independent t-tests were performed to find significant qualitative and quantitative features respectively. Logistic-regression (LR) classifiers were implemented for evaluating performance of individual and various combinations of features in differentiating PCNSL vs GB. Performance evaluation was done via ROC-analysis. Pathological validation was performed to verify disintegration of vessel walls in GB and rim of viable neoplastic lymphoid cells with angiocentric-pattern in PCNSL. RESULTS: Three qualitative SWI features and four quantitative DCE-MRI features (rCBVcorr, Kep, Ve, and necrosis-volume-percentage) were significantly different (p < 0.05) between PCNSL and GB. Best diagnostic performance was observed with LR classifier using SWI features (AUC-0.99). The inclusion of quantitative features with SWI feature did not improve the differentiation accuracy. CONCLUSIONS: The combination of three qualitative SWI features using LR provided the highest accuracy in differentiating PCNSL and GB. Thin-linear-uninterrupted-intra-tumoral-vasculature in PCNSL and broken-intra-tumoral-microvasculature with hemorrhage in GB are the major contributors to the differentiation.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Linfoma , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Sistema Nervioso Central/patología , Diagnóstico Diferencial , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Humanos , Linfoma/diagnóstico por imagen , Linfoma/patología , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
15.
Environ Res ; 215(Pt 1): 114199, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36058281

RESUMEN

In the present study, the microbial community residing at different depths of the landfill was characterized to assess their roles in serving as a methane sink. Physico-chemical characterization revealed the characteristic signatures of anaerobic degradation of organic matter in the bottom soil (50-60 cm) and, active process of aerobic denitrification in the top soil (0-10 cm). This was also reflected from the higher abundance of bacterial domain in the top soil metagenome represented by dominant phyla Proteobacteria and Actinobacteria which are prime decomposers of organic matter in landfill soils. The multiple fold higher relative abundances of the two most abundant genera; Streptomyces and Intrasporangium in the top soil depicted greater denitrifying taxa in top soil than the bottom soil. Amongst the aerobic methanotrophs, the genera Methylomonas, Methylococcus, Methylocella, and Methylacidiphilum were abundantly found in the top soil metagenome that were essential for oxidizing methane generated in the landfill. On the other hand, the dominance of archaeal domain represented by Methanosarcina and Methanoculleus in the bottom soil highlighted the complete anaerobic digestion of organic components via acetoclasty, carboxydotrophy, hydrogenotrophy, methylotrophy. Functional characterization revealed a higher abundance of methane monooxygenase gene in the top soil and methyl coenzyme M reductase gene in the bottom soil that correlated with the higher relative abundance of aerobic methanotrophs in the top soil while methane generation being the active process in the highly anaerobic bottom soil in the landfill. The activity dependent abundance of endogenous microbial communities in the different zones of the landfill was further validated by microcosm studies in serum bottles which established the ability of the methanotrophic community for methane metabolism in the top soil and their potential to serve as sink for methane. The study provides a better understanding about the methanotrophs in correlation with their endogenous environment, so that these bacteria can be used in resolving the environmental issues related to methane and nitrogen management at landfill site.


Asunto(s)
Metano , Suelo , Bacterias/genética , Bacterias/metabolismo , Metagenoma , Nitrógeno , Oxidación-Reducción , Suelo/química , Microbiología del Suelo , Instalaciones de Eliminación de Residuos
16.
Curr Microbiol ; 79(4): 110, 2022 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35175411

RESUMEN

In 2019, amongst half a million new rifampicin-resistant tuberculosis (TB) cases, 78% were multi drug-resistant TB (MDR-TB). Access to rapid and Universal-Drug susceptibility testing (DST) to patients in remote areas is a major challenge to combat drug-resistant TB. To overcome this challenge, we had recently reported the development of 'TB Concentration & Transport kit' for bio-safe ambient temperature transport of dried sputum on filter-paper (Trans-Filter). The present study was conducted to evaluate the utility of DNA extracted from sputum on Trans-Filter in a Multiplex PCR-based sequencing assay (Mol-DSTseq) for diagnosing drug-resistant TB. The developed Mol-DSTseq assays were standardized on Mycobacterium tuberculosis clinical isolates (n = 98) and further validated on DNA extracted from sputum on Trans-Filter (n = 100). Using phenotypic DST as gold standard, the Mol-DSTseq assay showed 100% (95% Confidence Interval [CI] 79.4-100%) and 73.3% (95% CI 54.1-87.7%) sensitivity for detecting rifampicin and isoniazid resistance with a specificity of 85.1% (95% CI 66.2-95.8%) and 100% (95% CI:82.3-100%), respectively. For fluoroquinolones and aminoglycosides, the Mol-DSTseq assay showed a sensitivity of 78.5% (95% CI 49.2-95.3%) and 66.6% (95% CI 9.4-99.1%) with a specificity of 88.2% (95% CI 72.5-96.7%) and 100% (95% CI 93.1-100%), respectively. The Mol-DSTseq assays exhibited a high concordance of ~ 83-96% (κ value: 0.65-0.81) with phenotypic DST for all drugs. In conclusion, the 'TB Concentration and Transport kit' was compatible with Mol-DSTseq assays and has the potential to provide 'Universal-DST' to patients residing in distant areas in high burden countries, like India for early initiation of anti-tubercular treatment.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Antituberculosos/farmacología , Humanos , Isoniazida , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/genética , Sensibilidad y Especificidad , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
17.
World J Microbiol Biotechnol ; 38(8): 140, 2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35705700

RESUMEN

Municipal landfills are known for methane production and a source of nitrate pollution leading to various environmental issues. Therefore, this niche was selected for the isolation of one-carbon (C1) utilizing bacteria with denitrifying capacities using anaerobic enrichment on nitrate mineral salt medium supplemented with methanol as carbon source. Eight axenic cultures were isolated of which, isolate AAK/M5 demonstrated the highest methanol removal (73.28%) in terms of soluble chemical oxygen demand and methane removal (41.27%) at the expense of total nitrate removal of 100% and 33% respectively. The whole genome characterization with phylogenomic approach suggested that the strain AAK/M5 could be assigned to Pseudomonas aeruginosa with close neighbours as type strains DVT779, AES1M, W60856, and LES400. The circular genome annotation showed the presence of complete set of genes essential for methanol utilization and complete denitrification process. The study demonstrates the potential of P. aeruginosa strain AAK/M5 in catalysing methane oxidation thus serving as a methane sink vis-à-vis utilization of nitrate. Considering the existence of such bacteria at landfill site, the study highlights the need to develop strategies for their enrichment and designing of efficient catabolic activity for such environments.


Asunto(s)
Suelo , Residuos Sólidos , Bacterias/metabolismo , Carbono/metabolismo , Desnitrificación , Genómica , Metano/metabolismo , Metanol/metabolismo , Nitratos/metabolismo , Oxidación-Reducción , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Suelo/química , Instalaciones de Eliminación de Residuos
18.
Mol Hum Reprod ; 27(6)2021 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-34051087

RESUMEN

Embryo implantation is a highly complex process involving many regulatory factors, including several micro RNAs (miRNAs/miRs). One miRNA present in the stromal cells of normal endometrium is miR-149, which targets poly (ADP-ribose) polymerase 2 (PARP-2), a gene involved in endometrial receptivity for trophoblast implantation. However, the precise role of miR-149 in the endometrial receptivity during blastocyst implantation is still unknown. We studied miR-149-dependent PARP-2 regulation during trophoblast attachment to endometrial epithelial cells. Using FISH, we found that miR-149 is expressed in mouse endometrial epithelial and stromal cells at implantation and inter-implantation sites. Endometrial receptivity for embryo implantation and attachment is inhibited by the upregulation of miR-149 in the endometrium. Our RT-PCR analysis revealed downregulation of miR-149 in the implantation region of the uterus during the receptive stage (Day 5, 0500 h, p.c.) in the mouse. Under in-vitro conditions, miR-149 overexpression in human endometrial epithelial cells (hEECs) abrogated the human trophoblastic cells spheroid and mouse blastocyst attachment. Subsequently, miR-149 also regulates transformed human endometrial stromal cell (T-hESCs) decidualization by downregulating PARP-2 and upregulating caspase-8 proteins. Overexpression of miR-149 in hEECs and downregulated PARP-2 protein expression, reconfirming that PARP-2 is a downstream target of miR-149 in endometrial cells as well. miR-149 is also able to alter the expression of caspase-8, another PARP-2 regulator. In conclusion, our data indicate that miR-149 is one of the regulators of endometrial receptivity and decidualization for trophoblast implantation, and it exerts the effects by acting on the downstream targets PARP-2 and caspase-8.


Asunto(s)
Implantación del Embrión/fisiología , Endometrio/metabolismo , Células Epiteliales/metabolismo , MicroARNs/genética , Poli(ADP-Ribosa) Polimerasas/genética , Células del Estroma/metabolismo , Trofoblastos/fisiología , Regiones no Traducidas 3'/genética , Animales , Apoptosis , Secuencia de Bases , Sitios de Unión , Biomarcadores , Caspasa 8/biosíntesis , Caspasa 8/genética , Técnicas de Cocultivo , Simulación por Computador , Endometrio/citología , Femenino , Ratones , MicroARNs/metabolismo , Poli(ADP-Ribosa) Polimerasas/biosíntesis , Embarazo , ARN Mensajero/genética , ARN Mensajero/metabolismo
19.
NMR Biomed ; 34(4): e4468, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33543519

RESUMEN

Chemical exchange saturation transfer (CEST) MRI is a non-invasive molecular imaging technique with potential applications in pre-clinical and clinical studies. Applications of amide proton transfer-weighted (APT-w), glutamate-weighted (Glu-w) and creatine-weighted (Cr-w) CEST, among others, have been reported. In general, CEST data are acquired at multiple offset-frequencies. In reported studies, different offset-frequency step sizes and interpolation methods have been used during B0 inhomogeneity correction of data. The objective of the current study was to evaluate the effects of different step sizes and interpolation methods on CEST value computation. In the current study, simulation (Glu-w, Cr-w and APT-w) and experimental data from the brain were used. Experimental CEST data (Glu-w) were acquired from human volunteers at 7 T and brain tumor patients (APT-w) at 3 T. During B0 inhomogeneity correction, different interpolation methods (polynomial [degree-1, 2 and 3], cubic-Hermite, cubic-spline and smoothing-spline) were compared. CEST values were computed using asymmetry analysis. The effects of different step sizes and interpolation methods were evaluated using coefficient of variation (CV), normalized mean square error (nMSE) and coefficient of correlation parameters. Additionally, an optimum interpolation method for APT-w values was selected based upon fitting accuracy, T-test, receiver operating characteristic analysis, and its diagnostic performance in differentiating low-grade and high-grade tumors. CV and nMSE increase with an increase in step size irrespective of the interpolation method (except for cubic-Hermite and cubic-spline). The nMSE of Cr-w and Glu-w CEST values were least for polynomial (degree-2 and 3). The quality of Glu-w CEST maps became coarse with the increase in step size. There was a significant difference (P < .05) between low-grade and high-grade tumors using polynomial interpolation (degree-1, 2 and 3); however, linear interpolation outperforms other methods for APT-w data, providing the highest sensitivity and specificity. In conclusion, depending upon the saturation parameters and field strength, optimization of step size and interpolation should be carried out for different CEST metabolites/molecules. Glu-w, Cr-w and APT-w CEST data should be acquired with a step size of between 0.2 and 0.3 ppm. For B0 inhomogeneity correction, polynomial (degree-2) should be used for Glu-w and Cr-w CEST data at 7 T and linear interpolation should be used for APT-w data at 3 T for a limited frequency range.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen Molecular/métodos , Adulto , Simulación por Computador , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Adulto Joven
20.
NMR Biomed ; 34(7): e4526, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33880799

RESUMEN

In acute-ischemic-stroke patients, penumbra assessment plays a significant role in treatment outcome. MR perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) mismatch ratio can provide penumbra assessment. Recently reported studies have shown the potential of susceptibility-weighted imaging (SWI) in the qualitative assessment of penumbra. We hypothesize that quantitative penumbra assessment using SWI-DWI can provide an alternative to the PWI-DWI approach and this can also reduce the overall scan-time. The purpose of the current study was to develop a framework for accurate quantitative assessment of penumbra using SWI-DWI and its validation with PWI-DWI-based quantification. In the current study, the arterial-spin-labelling (ASL) technique has been used for PWI. This retrospective study included 25 acute-ischemic-stroke patients presenting within 24 hours of the last noted baseline condition of stroke onset. Eleven patients also had follow-up MRI within 48 hours. MRI acquisition comprised DWI, SWI, pseudo-continuous-ASL (pCASL), FLAIR and non-contrast-angiography sequences. A framework was developed for the enhancement of prominent hypo-intense vein signs followed by automatic segmentation of the SWI penumbra ROI. Apparent-diffusion-coefficient (ADC) maps and cerebral-blood-flow (CBF) maps were computed. The infarct core ROI from the ADC map and the ASL penumbra ROI from CBF maps were segmented semiautomatically. The infarct core volume, SWI penumbra volume (SPV) and pCASL penumbra volume were computed and used to calculate mismatch ratios MRSWIADC and MRCBFADC . The Dice coefficient between the SWI penumbra ROI and ASL penumbra ROI was 0.96 ± 0.07. MRSWIADC correlated well (r = 0.90, p < 0.05) with MRCBFADC , which validates the hypothesis of accurate penumbra assessment using the SWI-DWI mismatch ratio. Moreover, a significant association between high SPV and the presence of vessel occlusion in the MR angiogram was observed. Follow-up data showed salvation of penumbra tissue (location and volumes predicted by proposed framework) by treatments. Additionally, functional-outcome analysis revealed 93.3% of patients with MRSWIADC > 1 benefitted from revascularization therapy. Overall, the proposed automated quantitative assessment of penumbra using the SWI-DWI mismatch ratio performs equivalently to the ASL PWI-DWI mismatch ratio. This approach provides an alternative to the perfusion sequence required for penumbra assessment, which can reduce scan time by 17% for the protocol without a perfusion sequence.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Arterias Cerebrales/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Perfusión , Marcadores de Spin , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
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