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1.
Plant Physiol ; 194(3): 1336-1357, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-37930810

RESUMO

Plants must rapidly and dynamically adapt to changes in their environment. Upon sensing environmental signals, plants convert them into cellular signals, which elicit physiological or developmental changes that allow them to respond to various abiotic and biotic cues. Because plants can be simultaneously exposed to multiple environmental cues, signal integration between plant cells, tissues, and organs is necessary to induce specific responses. Recently, CLAVATA3/EMBRYO SURROUNDING REGION-related (CLE) peptides and their cognate CLAVATA-type receptors received increased attention for their roles in plant-environment interactions. CLE peptides are mobile signaling molecules, many of which are induced by a variety of biotic and abiotic stimuli. Secreted CLE peptides are perceived by receptor complexes on the surface of their target cells, which often include the leucine-rich repeat receptor-like kinase CLAVATA1. Receptor activation then results in cell-type and/or environment-specific responses. This review summarizes our current understanding of the diverse roles of environment-regulated CLE peptides in modulating plant responses to environmental cues. We highlight how CLE signals regulate plant physiology by fine-tuning plant-microbe interactions, nutrient homeostasis, and carbon allocation. Finally, we describe the role of CLAVATA receptors in the perception of environment-induced CLE signals and discuss how diverse CLE-CLAVATA signaling modules may integrate environmental signals with plant physiology and development.


Assuntos
Interação Gene-Ambiente , Transdução de Sinais , Transporte Biológico , Carbono , Peptídeos
2.
Breast Cancer Res Treat ; 206(1): 19-30, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38668856

RESUMO

BACKGROUND: Evaluation of axillary lymph nodes status in cN0 axilla is performed by sentinel lymph node biopsy (SLNB) utilizing a combination of radioactive isotope and blue dye or alternative to isotope like Indocyanine green (ICG). Both are very resource-intensive; which has prompted development of low-cost technique of Fluorescein Sodium (FS)-guided SLNB. This systematic review and meta-analysis evaluate the diagnostic performance of FS-guided SLNB in early breast cancer. OBJECTIVES: The objective was to evaluate the diagnostic performance of FS for sentinel lymph node biopsy. METHODS: Eligibility criteria: Studies where SLNB was performed using FS. INFORMATION SOURCES: PubMed, EMBASE, Cochrane library and online clinical trial registers. Risk of bias: Articles were assessed for risk of bias using the QUADAS-2 tool. SYNTHESIS OF RESULTS: The main summary measures were pooled Sentinel Lymph Node Identification Rate (SLN-IR) and pooled False Negative Rate (FNR) using random-effects model. RESULTS: A total of 45 articles were retrieved by the initial systematic search. 7 out of the 45 studies comprising a total of 332 patients were included in the meta-analysis. The pooled SLN-IR was 93.2% (95% confidence interval [CI], 0.87-0.97; 87% to 97%). Five validation studies were included for pooling the false negative rate and included a total of 211 patients. The pooled FNR was 5.6% (95% confidence interval [CI], 2.9-9.07). CONCLUSION: Fluorescein-guided SLNB is a viable option for detection of lymph node metastases in clinically node negative patients with early breast cancer. It achieves a high pooled Sentinel Lymph Node Identification Rate (SLN-IR) of 93% with a false negative rate of 5.6% for the detection of axillary lymph node metastasis.


Assuntos
Neoplasias da Mama , Fluoresceína , Metástase Linfática , Biópsia de Linfonodo Sentinela , Humanos , Biópsia de Linfonodo Sentinela/métodos , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico , Feminino , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Linfonodo Sentinela/patologia , Axila , Biópsia Guiada por Imagem/métodos
3.
Small ; : e2402953, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923392

RESUMO

While peptide-based drug development is extensively explored, this strategy has limitations due to rapid excretion from the body (or shorter half-life in the body) and vulnerability to protease-mediated degradation. To overcome these limitations, a novel strategy for the development of a peptide-based anticancer agent is introduced, utilizing the conformation switch property of a chameleon sequence stretch (PEP1) derived from a mycobacterium secretory protein, MPT63. The selected peptide is then loaded into a new porous organic polymer (PG-DFC-POP) synthesized using phloroglucinol and a cresol derivative via a condensation reaction to deliver the peptide selectively to cancer cells. Utilizing ensemble and single-molecule approaches, this peptide undergoes a transition from a disordered to an alpha-helical conformation, triggered by the acidic environment within cancer cells that is demonstrated. This adopted alpha-helical conformation resulted in the formation of proteolysis-resistant oligomers, which showed efficient membrane pore-forming activity selectively for negatively charged phospholipids accumulated in cancer cell membranes. The experimental results demonstrated that the peptide-loaded PG-DFC-POP-PEP1 exhibited significant cytotoxicity in cancer cells, leading to cell death through the Pyroptosis pathway, which is established by monitoring numerous associated events starting from lysosome membrane damage to GSDMD-induced cell membrane demolition. This novel conformational switch-based drug design strategy is believed to have great potential in endogenous environment-responsive cancer therapy and the development of future drug candidates to mitigate cancers.

4.
J Clin Microbiol ; 62(3): e0104823, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38329335

RESUMO

Human granulocytic anaplasmosis (HGA) is an emerging, rickettsial tick-borne disease caused by Anaplasma phagocytophilum. Sero-epidemiological data demonstrate that this pathogen has a worldwide distribution. The diagnosis of HGA requires a high index of clinical suspicion, even in endemic areas. In recent years, HGA has increasingly been reported from Asia and described in China, Japan, and Korea. We serologically and molecularly screened 467 patients with clinical suspicion of Anaplasmosis. The present study describes the epidemiology, clinical, and laboratory details of 6 confirmed and 43 probable cases of human granulocytic anaplasmosis. One of the HGA patients developed secondary invasive opportunistic Aspergillus fumigatus and Acinetobacter baumanii infection during the illness, which resulted in a fatal infection. The HGA patients without severe complications had excellent treatment responses to doxycycline. The emergence of this newly recognized tick-borne zoonotic HGA in North India is a significant concern for public health and is likely underdiagnosed, underreported, and untreated. Hence, it is also essential to establish a well-coordinated system for actively conducting tick surveillance, especially in the forested areas of the country.IMPORTANCEThe results of the present study show the clinical and laboratory evidence of autochthonous cases of Anaplasma phagocytophilum in North India. The results suggest the possibility of underdiagnosis of HGA in this geographical area. One of the HGA patients developed secondary invasive opportunistic Aspergillus fumigatus and Acinetobacter baumanii infection during the illness, which resulted in a fatal infection.


Assuntos
Anaplasma phagocytophilum , Anaplasmose , Doenças Transmitidas por Carrapatos , Animais , Humanos , Anaplasmose/diagnóstico , Anaplasmose/tratamento farmacológico , Anaplasmose/epidemiologia , Doxiciclina/uso terapêutico , China/epidemiologia , Índia
5.
Chemistry ; 30(13): e202303287, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37997510

RESUMO

An efficient and short synthesis of fused dihydroisoquinolines, diaryl substituted pyridine derivatives in good to high yields has been established by using an environmentally safe, solvent-metal-oxidant-free tandem approach. In this article, we discuss how the electrocyclic reaction is more pronounced in the solid phase in the presence of urea, whereas the typical aza-Michael addition is more prominent in presence of arylamine in the solution phase for 3-(2-formylcycloalkenyl)acrylic ester derivative substrates. The wide range of substrates and urea-promoted neat synthesis made our approach more significant in medical and also analytical science. Moreover, an isoquinoline alkaloid decumbenine B analogue has been synthesized by using our newly developed neat methodology. We have also investigated the photophysical properties of the synthesized fused dihydroisoquinoline derivatives. One of the synthesized molecules was used as a sensor for the selective detection of toxic picric acid. Therefore, the effective neat synthesis and molecular sensing applications of these compounds made our approach more exciting in the field of heterocyclic chemistry.

6.
World J Surg ; 48(6): 1433-1439, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38658165

RESUMO

BACKGROUND: Excess and prolonged axillary drainage is a frequent nuisance following axillary lymph node dissection (ALND) in breast cancer patients. No consensus exists about the best method to prevent this consistently and reliably. Tranexamic acid (TA) has been found to reduce the amount and duration of drainage, but the reduction is not optimal. We hypothesized that systemic administration of TA along with the topical application of hemocoagulase (H) to the axillary dissection bed may decrease the cumulative axillary drain output and shorten the requirement of drainage after ALND as compared to placebo. PATIENT AND METHODS: Seventy women undergoing ALND for breast carcinoma were randomized into two groups, the intervention (TA + H) group and the control (C) group. The cumulative drain output (primary objective), duration of drainage, incidence of seroma formation after drain removal, number of seroma aspirations required, volume of seroma aspirated, and incidence of surgical site infection (SSI) were compared. RESULTS: The mean cumulative output in the TA + H group was significantly lower than the C group (290 ± 200 mL vs. 552 ± 369 mL, p < 0.001). Axillary drains were removed significantly earlier in the TA + H group (6.6 ± 2.2 vs. 11.7 ± 6.0 days, p < 0.001), but the incidence of seroma formation (p = 0.34), number of aspirations required (p = 0.33), volume of seroma aspirated (p = 0.47), and the incidence of SSI (p = 0.07) were similar. CONCLUSIONS: Perioperative systemic administration of tranexamic acid along with topical application of H to the axillary dissection bed is effective in reducing cumulative axillary drain output after ALND. This strategy may also facilitate earlier removal of suction drains.


Assuntos
Administração Tópica , Antifibrinolíticos , Axila , Neoplasias da Mama , Drenagem , Excisão de Linfonodo , Ácido Tranexâmico , Humanos , Feminino , Ácido Tranexâmico/administração & dosagem , Ácido Tranexâmico/uso terapêutico , Neoplasias da Mama/cirurgia , Pessoa de Meia-Idade , Método Duplo-Cego , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/uso terapêutico , Drenagem/métodos , Adulto , Batroxobina/administração & dosagem , Batroxobina/uso terapêutico , Seroma/prevenção & controle , Seroma/etiologia , Idoso , Resultado do Tratamento , Assistência Perioperatória/métodos , Hemostáticos/administração & dosagem , Hemostáticos/uso terapêutico
7.
Mol Cell Neurosci ; 126: 103886, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567489

RESUMO

Polyglutamine (polyQ) induced neurodegeneration is one of the leading causes of progressive neurodegenerative disorders characterized clinically by deteriorating movement defects, psychiatric disability, and dementia. Calcium [Ca2+] homeostasis, which is essential for the functioning of neuronal cells, is disrupted under these pathological conditions. In this paper, we simulated Huntington's disease phenotype in the neuronal cells of the Drosophila eye and identified [Ca2+] pump, sarco-endoplasmic reticulum calcium ATPase (SERCA), as one of the genetic modifiers of the neurodegenerative phenotype. This paper shows genetic and molecular interaction between polyglutamine (polyQ) aggregates, SERCA and DIAP1. We present evidence that polyQ aggregates interact with SERCA and alter its dynamics, resulting in a decrease in cytosolic [Ca2+] and an increase in ER [Ca2+], and thus toxicity. Downregulating SERCA lowers the enhanced calcium levels in the ER and rescues, morphological and functional defects caused due to expanded polyQ repeats. Cell proliferation markers such as Yorkie (Yki), Scalloped (Sd), and phosphatidylinositol 3 kinases/protein kinase B (PI3K/Akt), also respond to varying levels of calcium due to genetic manipulations, adding to the amelioration of degeneration. These results imply that neurodegeneration due to expanded polyQ repeats is sensitive to SERCA activity, and its manipulation can be an important step toward its therapeutic measures.


Assuntos
Cálcio , Drosophila , Proteínas Inibidoras de Apoptose , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Animais , Apoptose , Cálcio/metabolismo , ATPases Transportadoras de Cálcio , Drosophila/metabolismo , Retículo Endoplasmático/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas de Drosophila
8.
J Assoc Physicians India ; 72(1): 18-21, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38736069

RESUMO

INTRODUCTION: The world has changed tremendously for patients suffering from diabetes mellitus with the development of cutting-edge technologies like continuous glucose monitoring and flash glucose monitoring systems. Now, the details of constant fluctuations of glucose in their blood can be monitored not only by medical professionals but also by patients, and this is called glycemic variability (GV). Traditional metrics of glycemic control measurement, such as glycated hemoglobin (HbA1c), fail to reflect various short-term glycemic changes like postprandial hyperglycemia and hypoglycemic episodes, paving the way to the occurrence of various diabetic complications even in asymptomatic, well-controlled diabetic patients. This need for advanced management of diabetes and effective monitoring of these swings in blood glucose can be met by using a continuous glucose monitoring system (CGMS). AIM AND OBJECTIVE: To evaluate the extent of GV in well-controlled type 2 diabetes mellitus (T2DM) patients using a flash CGMS and to assess the correlation between GV and HbA1c. MATERIALS AND METHODS: A hospital-based prospective observational study was carried out from May 2020 to Oct 2021 at the Department of Medicine, SMS Hospital, Jaipur, Rajasthan (India), after approval from the Ethics Committee of the institution. A total of 30 patients with well-controlled T2DM (HbA1c was ≥6.5, but ≤7.5) were included in the study using simple random techniques after written informed consent from patients. Patients were studied for glycemic excursions over a period of 7 days by using FreeStyle® Libre Pro™, which is a flash glucose monitoring system. The CGM sensor was attached to the left upper arm of the patient on day 0 and removed on day 7. The data recorded in the sensor was then retrieved using pre-installed computer software and analyzed using standard CGM metrics like standard deviation (SD), percentage coefficient of variation (%CV), time above range (TAR), time below range (TBR), and time in range (TIR), out of which %CV was used to quantify GV. %CV has been used to cluster patients into four cohorts from best to worst, namely: best/low CV ≤ 10%, intermediate CV from 10 to 20%, high CV from 20 to 30%, and very high CV of >30%. Scatterplots are used to establish correlations between various parameters. RESULT: Data from a total of 30 patients were analyzed using CGMS and thus used for calculating standard CGM metrics; glucose readings every 15 minutes were recorded consecutively for 7-day periods, making it a total of 672 readings for each patient. Interpreting the CGM data of all 30 patients, the following results were found: the mean blood glucose of all cases is 134.925 ± 22.323 mg/dL, the mean SD of blood glucose of all cases is 35.348 ± 9.388 mg/dL, the mean of %CV of all cases is 26.376 ± 6.193%. CGM parameters of time are used in the form of percentages, and the following results were found: the mean of TAR, TBR, and TIR is 14.425 ± 13.211, 5.771 ± 6.808, and 82.594 ± 12.888%, respectively. Clustering the patients into cohorts, the proportion of patients exhibiting best/low %CV (10%) is 0, intermediate %CV (10-20%) is 16.67% (five out of 30 patients), high %CV (20-30%) is 50% (15 out of 30 patients) and very high %CV (>30%) is 33.33% (10 out of 30 patients). Also, there is no significant correlation found between HbA1c and %CV (ρ = 0.076, p-value = 0.690); a significant negative correlation was found between %CV and TIR (ρ = -0.604, p < 0.001S); a positive correlation of %CV with TAR and TBR is significant (ρ = 0.816, p-value of <0.001). CONCLUSION: Using a flash CGMS device and considering %CV as the parameter and primary measure of GV, the study demonstrated the overall instability of a person's glycemic control, making note of unrecognized events of hypoglycemia and hyperglycemia in asymptomatic well-controlled T2DM patients, revealing the overall volatile glycemic control. The most important finding of this study is that even those diabetics who are considered well-controlled experience a great degree of GV as assessed by CGM-derived metrics. This study also demonstrated that there is no significant correlation between HbA1c and GV, suggesting that patients may not have optimal control of their diabetes despite having "normal HbA1c" values; hence, GV can be considered an HbA1c-independent danger factor, having more harmful effects than sustained hyperglycemia in the growth of diabetic complications. So, by using CGM-derived metrics, the measurement of GV has the potential to complement HbA1c data. In this manner, a more comprehensive assessment of glycemic excursions can be provided for better treatment decisions, thereby facilitating optimal glycemic control, which is essential for reducing overall complications and promoting good quality of life.


Assuntos
Automonitorização da Glicemia , Glicemia , Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Humanos , Diabetes Mellitus Tipo 2/sangue , Automonitorização da Glicemia/métodos , Automonitorização da Glicemia/instrumentação , Glicemia/análise , Hemoglobinas Glicadas/análise , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Controle Glicêmico/métodos , Adulto , Idoso , Monitoramento Contínuo da Glicose
9.
BMC Plant Biol ; 23(1): 228, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120525

RESUMO

BACKGROUND: Moth bean (Vigna aconitifolia) is an underutilized, protein-rich legume that is grown in arid and semi-arid areas of south Asia and is highly resistant to abiotic stresses such as heat and drought. Despite its economic importance, the crop remains unexplored at the genomic level for genetic diversity and trait mapping studies. To date, there is no report of SNP marker discovery and association mapping of any trait in this crop. Therefore, this study aimed to dissect the genetic diversity, population structure and marker-trait association for the flowering trait in a diversity panel of 428 moth bean accessions using genotyping by sequencing (GBS) approach. RESULTS: A total of 9078 high-quality single nucleotide polymorphisms (SNPs) were discovered by genotyping of 428 moth bean accessions. Model-based structure analysis and PCA grouped the moth bean accessions into two subpopulations. Cluster analysis revealed accessions belonging to the Northwestern region of India had higher variability than accessions from the other regions suggesting that this region represents its center of diversity. AMOVA revealed more variations within individuals (74%) and among the individuals (24%) than among the populations (2%). Marker-trait association analysis using seven multi-locus models including mrMLM, FASTmrEMMA FASTmrEMMA, ISIS EM-BLASSO, MLMM, BLINK and FarmCPU revealed 29 potential genomic regions for the trait days to 50% flowering, which were consistently detected in three or more models. Analysis of the allelic effect of the major genomic regions explaining phenotypic variance of more than 10% and those detected in at least 2 environments showed 4 genomic regions with significant phenotypic effect on this trait. Further, we also analyzed genetic relationships among the Vigna species using SNP markers. The genomic localization of moth bean SNPs on genomes of closely related Vigna species demonstrated that maximum numbers of SNPs were getting localized on Vigna mungo. This suggested that the moth bean is most closely related to V. mungo. CONCLUSION: Our study shows that the north-western regions of India represent the center of diversity of the moth bean. Further, the study revealed flowering-related genomic regions/candidate genes which can be potentially exploited in breeding programs to develop early-maturity moth bean varieties.


Assuntos
Estudo de Associação Genômica Ampla , Vigna , Vigna/genética , Genótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética
10.
Crit Rev Biotechnol ; : 1-20, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37455414

RESUMO

The intensification of food production via conventional crop breeding alone is inadequate to cater for global hunger. The development of precise and expeditious high throughput reverse genetics approaches has hugely benefited modern plant breeding programs. Targeting Induced Local Lesions in Genomes (TILLING) is one such reverse genetics approach which employs chemical/physical mutagenesis to create new genetic sources and identifies superior/novel alleles. Owing to technical limitations and sectional applicability of the original TILLING protocol, it has been timely modified. Successions include: EcoTILLING, Double stranded EcoTILLING (DEcoTILLING), Self-EcoTILLING, Individualized TILLING (iTILLING), Deletion-TILLING (De-TILLING), PolyTILLING, and VeggieTILLING. This has widened its application to a variety of crops and needs. They can characterize mutations in coding as well as non-coding regions and can overcome complexities associated with the large genomes. Combining next generation sequencing tools with the existing TILLING protocols has enabled screening of huge germplasm collections and mutant populations for the target genes. In silico TILLING platforms have transformed TILLING into an exciting breeding approach. The present review outlines these multifarious TILLING modifications for precise mutation detection and their application in advance breeding programmes together with relevant case studies. Appropriate use of these protocols will open up new avenues for crop improvement in the twenty first century.

11.
Langmuir ; 39(24): 8450-8462, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37279383

RESUMO

Developing a solid organic emitter based on an oxazaborinine complex with improved photophysical characteristics has become essential to fulfilling the rising need for optical and electrochemical technology. Two oxazaborinine complexes (TNB (a tri-naphthalene boron complex) and DNB (a di-naphthalene boron complex)) decorated with naphthalene and triphenylamine have been developed, which show emission in the red light region in the solid phase. Their effectiveness as asymmetric supercapacitor electrodes in aqueous electrolytes is also being studied. Polynapthaldimine-substituted DNI (di-naphthalene imine) and TNI (tri-naphthalene imine) have been initially synthesized and converted to a N,O-linked boron complex. TNB in solids (λem 660 nm) and the polydimethylsiloxane (PDMS) composite (λem 632 nm) emit pure red light. The optimized structure has been generated, and the HOMO-LUMO energy was calculated with the help of density functional theory (DFT). Due to the higher conjugation effect and lower HOMO-LUMO energy difference, TNB could be used as a supercapacitor electrode. In a three-electrode configuration, TNB has a maximum specific capacitance of 896.25 F/g. Furthermore, an asymmetric supercapacitor device (ASC) was fabricated in an aqueous electrolyte using TNB as a positive electrode having a high specific capacitance of 155 F/g. Even in an aqueous electrolyte, the ASC device reached the operating potential window of 0 to 1.4 V with an enhanced energy density of 42.19 W h/kg and ∼96% cyclic stability after 10 000 cycles. The reported oxazaborinine complex and its electrochemical efficiency in aqueous electrolytes make it ideal for supercapacitor applications and directly impact the development of advanced electrodes for next-generation supercapacitors.

12.
Inorg Chem ; 62(30): 11920-11931, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37462947

RESUMO

Both natural enzymatic systems and synthetic porous material catalysts utilize well-defined and uniform channels to dictate reaction selectivities on the basis of size or shape. Mimicry of this design element in homogeneous systems is generally difficult owing to the flexibility inherent in most small molecular species. Herein, we report the synthesis of a tripodal ligand scaffold that orients a narrow and rigid cavity atop accessible metal coordination space. The permanent void is formed through a macrocyclization reaction whereby the 3,5-dihydroxyphenyl arms are covalently linked through methylene bridges. Deprotonative metallation leads to anionic and coordinatively unsaturated complexes of divalent cobalt, nickel, and zinc. An analogous series of trigonal monopyramidal complexes bearing a nonmacrocyclized variant of the tripodal ligand are also reported. Physical characterization of the coordination complexes has been carried out using multiple spectroscopic techniques (NMR, EPR, and UV-vis), cyclic voltammetry, and X-ray diffraction. Complexes of the macrocyclized [LOCH2O]3- ligand retain a rigid cavity upon metallation, with this cavity guarding the entrance to the open axial coordination site. Through a combination of spectroscopic and computational studies, it is shown that acetonitrile entry into the void is sterically precluded, disrupting anticipated coordination at the intracavity site.

13.
Phys Chem Chem Phys ; 25(20): 14147-14157, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37162325

RESUMO

Telomerase is an RNA-dependent DNA polymerase that plays a role in the maintenance of the 3' end of the eukaryotic chromosome, known as a telomere, by catalyzing the DNA polymerization reaction in cancer and embryonic stem cells. The detailed molecular details of the DNA polymerization by telomerase, especially the general base for deprotonating the terminal 3'-hydroxyl, which triggers the chemical reaction, remain elusive. We conducted a computational investigation using hybrid quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) simulations to probe the detailed mechanism of the reaction. Our simulations started with the telomerase:RNA:DNA:dNTP ternary complex, and by using enhanced sampling QM/MM MD simulations, we probed the general base involved directly in the polymerization. We report the participation of an aspartate (Asp344) coordinated to Mg and an active site water molecule, jointly acting as a base during nucleic acid addition. The Asp344 residue remains transiently protonated during the course of the reaction, and later it deprotonates by transferring its proton to the water at the end of the reaction.


Assuntos
Simulação de Dinâmica Molecular , Telomerase , Polimerização , Telomerase/química , Telomerase/genética , Telomerase/metabolismo , DNA/química , Água
14.
World J Surg ; 47(2): 478-488, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36310323

RESUMO

INTRODUCTION: Evaluation of axillary lymph nodes after sentinel lymph node biopsy (SLNB) in breast cancer is mostly done by intra-operative frozen section biopsy (FSB) and/ or touch imprint cytology (TIC). In this systematic review and meta-analysis, we have compared the accuracy of the two modalities. METHODS: PubMed, EMBASE, and Cochrane electronic databases were searched for articles comparing TIC with FSB. Articles were assessed for methodological and reporting quality. The main summary measures were pooled sensitivity, pooled specificity, and diagnostic accuracy using bivariate generalized linear mixed models using random effects. RESULTS: Fourteen studies were included. The pooled sensitivity, specificity, and diagnostic accuracy for FSB were 78%, 100%, and 98.57%. For TIC, the pooled sensitivity, specificity, and diagnostic accuracy were 74%, 98%, and 98.37%. For both methods, visual inspection of summary ROC curves and of forest plots did not show significant heterogeneity. CONCLUSION: TIC showed comparable sensitivity, specificity, and accuracy to FSB and hence can be used as its substitute as a rapid and economical test for the detection of axillary lymph node metastasis during SLNB especially in low-resource settings.


Assuntos
Neoplasias da Mama , Linfadenopatia , Linfonodo Sentinela , Feminino , Humanos , Neoplasias da Mama/patologia , Secções Congeladas , Linfonodos/patologia , Linfadenopatia/patologia , Sensibilidade e Especificidade , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela/métodos
15.
Antonie Van Leeuwenhoek ; 116(4): 353-365, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36749507

RESUMO

One of the mechanistic approaches for explaining ageing is the oxidative stress theory of ageing. Saccharomyces cerevisiae has been used as a model to study ageing due to many factors. We have attempted to investigate if the differential ability to withstand oxidative stress can be correlated with their lifespans. In all the four strains studied (AP22, 699, 8C, and SP4), there was no age-associated increases in lipid peroxidation levels measured as thiobarbituric acid reactive substances (TBARS). Under induced oxidative stress conditions, there was an increased TBARS level in both the ages assessed with a quantum-fold increase in the stationary phase cells of AP22. In contrast, the late stationary phase cells of 8C exhibited the least susceptibility to induced oxidative stress. The level of TBARS in both exponential and late stationary phase cells of 699 was overall more than that in the other three strains. Protein carbonylation increased with age in 8C and 699. Induced stress increased carbonylation in the exponential cells of SP4 and 699 and the stationary phase cells of all four strains. Protein carbonylation data indicate that the AP22 cells exhibit decreased protein carbonylation vis-à-vis the other strains. Induced stress data showed that while the exponential cells of 699 are susceptible, the late stationary phase cells of 699 are most resistant. Western blotting analysis using anti-HNE antibodies showed two proteins of molecular mass ~ 56 and ~ 84 kDa that were selectively modified with age in all the strains. Under induced stress conditions, an additional protein of ~ 69 kDa was oxidized. Our investigation shows that the difference in lifespan between the four strains of S. cerevisiae may be regulated by oxidative stress. Knowledge of the identity of the oxidized proteins will significantly facilitate a better understanding of the effect of oxidative stress conditions on the cells of S. cerevisiae.


Assuntos
Senescência Celular , Estresse Oxidativo , Saccharomyces cerevisiae , Oxirredução , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Peroxidação de Lipídeos , Carbonilação Proteica , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Longevidade , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
Langenbecks Arch Surg ; 408(1): 200, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204607

RESUMO

BACKGROUND: We have performed an updated meta-analysis of randomized controlled trials (RCT) comparing total thyroidectomy (TT) with less than total thyroidectomy (LTT) for benign multinodular non-toxic goiter (BMNG). OBJECTIVES: The objective was to evaluate the effects and outcomes of TT as compared to LTT. METHODS: Eligibility criteria: RCTs comparing TT vs LTT. INFORMATION SOURCES: PubMed, Embase, Cochrane Library and online registers were searched for articles comparing TT with LTT. Risk of bias: Articles were assessed for risk of bias using the Cochrane's revised tool to assess risk of bias in randomized trials (RoB 2 tool). SYNTHESIS OF RESULTS: The main summary measures were risk difference using a random effects model. RESULTS: Five randomized controlled trials were included in the meta-analysis. Recurrence rate was lower for TT compared to LTT. Adverse events like temporary or permanent recurrent laryngeal nerve (RLN) palsy and permanent hypoparathyroidism were similar in both groups except for the rate of temporary hypoparathyroidism which was lower in the LTT group. DISCUSSION: All studies had unclear risk of bias for blinding of the participants and personnel and high risk of bias for certain selective reporting. This meta-analysis did not show any clear benefit or harm of either procedure (TT vs LTT) for goiter recurrence and re-operation rates (for both recurrence and incidental thyroid cancer). However, re-operation for goiter recurrence was significantly higher in the LTT group based on a single RCT. Evidence suggests increased rates of temporary hypoparathyroidism with TT but there was no difference in the rate of RLN palsy and permanent hypoparathyroidism between the two methods. The overall quality of evidence was low to moderate.


Assuntos
Bócio Nodular , Hipoparatireoidismo , Paralisia das Pregas Vocais , Humanos , Bócio Nodular/cirurgia , Bócio Nodular/etiologia , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Recidiva Local de Neoplasia/cirurgia , Hipoparatireoidismo/etiologia , Paralisia das Pregas Vocais/etiologia
17.
Indian J Med Res ; 157(6): 549-558, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37530310

RESUMO

Background & objectives: Multidrug-resistant (MDR) Acinetobacter baumannii is a serious threat for human health worldwide. The studies on agents targeting A. baumannii are imperative due to identified A. baumannii co-infections in COVID-19. Bacteriophages are promising antibacterial agents against drug-resistant bacteria. This study intended to isolate bacteriophages against MDR A. baumannii from the water of river Ganga, to be used potentially as therapeutic and disinfectant particles. Methods: Acinetobacter phages were isolated from the Ganga water collected from Kanpur and further tested on 50 MDR A. baumannii isolates to determine host range. The phages were morphologically characterized by transmission electron microscopy. The disinfectant property of the isolated phages was tested by spraying of bacteriophage cocktail on MDR A. baumannii contaminated plastic surface, analyzed by colony-forming unit (CFU) and bioluminescence assay (adenosine triphosphate monitoring). Results: A total of seven bacteriophages were isolated against MDR A. baumannii. The bacteriophages lysed three MDR A. baumannii isolates out of 50 tested, showing narrow host range. Electron microscopy revealed hexagonal heads and long tails of bacteriophages, belonging to order Caudovirales. The bacteriophage cocktail reduced the MDR A. baumannii load efficiently on plastic surface, evidenced by reduction in CFUs and bioluminescence. Interpretation & conclusions: The findings of this study suggest that the isolated bacteriophages are potential lytic agents for MDR A. baumannii clinical isolates, and may be used as potential therapeutic agents as well as disinfectant to combat MDR A. baumannii with due consideration to phage host specificity, with further characterization.


Assuntos
Acinetobacter baumannii , Bacteriófagos , COVID-19 , Humanos , Antibacterianos/farmacologia , Microscopia Eletrônica de Transmissão , Farmacorresistência Bacteriana Múltipla
18.
Appl Psychophysiol Biofeedback ; 48(3): 369-378, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37103669

RESUMO

Previous research has indicated a critical need for cost-effective alternative therapies. The present pilot study aimed to evaluate a novel, cost-effective therapy for treating insomnia. The study employed a randomized controlled trial with two groups: therapy and control. Participants were screened using research diagnostic criteria for insomnia recommended by the American Academy of Sleep Medicine (AASM) before undergoing simple randomization. The study included participants from Hindu, Muslim, and Christian faiths who were assigned to either the therapy group (Hare Krishna Mantra Based Cognitive Therapy: HMBCT) or the non-therapy group (control with relaxing music). Both groups underwent six weeks of treatment with traditional cognitive-behavioral therapy techniques, including stimulus control, sleep restriction, and sleep hygiene. Each week, participants in the therapy group received six 45-minute sessions of HMBCT in the evening and were asked to practice the therapy in the evening of the day of sleep recording. Sleep quality was assessed using behavioral measures, sleep logs, and polysomnography recordings before and after the six-week treatment period. There was a one-week period before and after the six weeks when no treatment was provided. Results showed that HMBCT significantly improved sleep quality measures, including a 61% reduction in Epworth Sleepiness Scale (ESS) scores and an 80% reduction in Insomnia Severity Index (ISI) scores. Participants did not take any sleep-inducing medication during the study. These findings suggest that adding mantra chanting to traditional cognitive-behavioral therapy may improve sleep quality.


Assuntos
Terapia Cognitivo-Comportamental , Meditação , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/terapia , Projetos Piloto , Meditação/métodos , Estudos de Viabilidade , Resultado do Tratamento , Terapia Cognitivo-Comportamental/métodos , Sono
19.
BMC Plant Biol ; 22(1): 99, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35247970

RESUMO

BACKGROUND: Alkaline soils cause low productivity in crop plants including lentil. Alkalinity adaptation strategies in lentil were revealed when morpho-anatomical and physio-biochemical observations were correlated with transcriptomics analysis in tolerant (PDL-1) and sensitive (L-4076) cultivars at seedling stage. RESULTS: PDL-1 had lesser salt injury and performed better as compared to L-4076. Latter showed severe wilting symptoms and higher accumulation of Na+ and lower K+ in roots and shoots. PDL-1 performed better under high alkalinity stress which can be attributed to its higher mitotic index, more accumulation of K+ in roots and shoots and less aberrantly dividing cells. Also, antioxidant enzyme activities, osmolytes' accumulation, relative water content, membrane stability index and abscisic acid were higher in this cultivar. Differentially expressed genes (DEGs) related to these parameters were upregulated in tolerant genotypes compared to the sensitive one. Significantly up-regulated DEGs were found to be involved in abscisic acid (ABA) signalling and secondary metabolites synthesis. ABA responsive genes viz. dehydrin 1, 9-cis-epoxycarotenoid dioxygenase, ABA-responsive protein 18 and BEL1-like homeodomain protein 1 had log2fold change above 4.0. A total of 12,836 simple sequence repeats and 4,438 single nucleotide polymorphisms were identified which can be utilized in molecular studies. CONCLUSIONS: Phyto-hormones biosynthesis-predominantly through ABA signalling, and secondary metabolism are the most potent pathways for alkalinity stress tolerance in lentil. Cultivar PDL-1 exhibited high tolerance towards alkalinity stress and can be used in breeding programmes for improving lentil production under alkalinity stress conditions.


Assuntos
Ácido Abscísico/metabolismo , Lens (Planta)/citologia , Lens (Planta)/genética , Lens (Planta)/metabolismo , Estresse Salino/genética , Tolerância ao Sal/genética , Análise de Sequência de RNA , Produtos Agrícolas/citologia , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Redes e Vias Metabólicas , Raízes de Plantas/metabolismo
20.
Plant Physiol ; 187(3): 1728-1745, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34618058

RESUMO

Iron (Fe) is an essential mineral element that governs the composition of natural plant communities and limits crop yield in agricultural ecosystems due to its extremely low availability in most soils, particularly at alkaline pH. To extract sufficient Fe from the soil under such conditions, some plants, including Arabidopsis (Arabidopsis thaliana), secrete Fe-mobilizing phenylpropanoids, which mobilize sparingly soluble Fe hydroxides by reduction and chelation. We show here that ectopic expression of the peptides IRONMAN (IMA1) and IMA2 improves growth on calcareous soil by inducing biosynthesis and secretion of the catecholic coumarin 7,8-dihydroxy-6-methoxycoumarin (fraxetin) via increased expression of MYB72 and SCOPOLETIN 8-HYDROXYLASE, a response that is strictly dependent on elevated environmental pH (pHe). By contrast, transcription of the cytochrome P450 family protein CYP82C4, catalyzing the subsequent hydroxylation of fraxetin to sideretin, which forms less stable complexes with iron, was strongly repressed under such conditions. We concluded that IMA peptides regulate processes supporting Fe uptake at both acidic and elevated pH by controlling gene expression upstream of or in concert with a putative pHe signal, adapting the plant to prevailing edaphic conditions. This regulatory pattern confers tolerance to calcareous soils by extending the pH range in which Fe can be efficiently absorbed from the soil. Our results further suggest that pHe calibrates the activities of components of the Fe deficiency response, accentuating processes that are most efficient under the prevailing conditions. Altering the expression of IMA peptides provides a route for generating plants adapted to calcareous soils.


Assuntos
Arabidopsis , Expressão Ectópica do Gene , Regulação da Expressão Gênica de Plantas , Ferro , Solo , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Alinhamento de Sequência , Solo/química
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