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1.
Heliyon ; 10(8): e28998, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644884

RESUMO

The primary issues in the Himalayan Rivers are sediment and cavitation degradation of the hydroelectric power turbine components. During the monsoon season, heavy material is transported by streams in hilly areas like the Himalayas through regular rainfalls, glacial and sub-glacial hydrological activity, and other factors. The severe erosion of hydraulic turbines caused by silt abrasion in these areas requires hydropower facilities to be regularly shut down for maintenance, affecting the plant's overall efficiency. This article provides an in-depth examination of the challenges that can lead to cavitation, silt erosion, and a decrease in the efficiency of various hydroelectric turbines, and it demands attention on the design, manufacture, operation, and maintenance of the turbines. This study's main objective is to critically evaluate earlier theoretical, experimental, and numerical evaluation-based studies (on cavitation and silt erosion) that are provided and addressed throughout the study. As a part of this study, various strategies for mitigating the effects of these problems and elongating the time that turbine may be utilized before they must be replaced have been provided.

2.
Heliyon ; 10(6): e26784, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38496867

RESUMO

Micro-electrical discharge machining (µEDM) is severely affected by tool wear and its process variants, which can lead to compromised precision and dimensional disruptions in micro-part production. Several attempts have been made to address this problem by suggesting offline and online (real-time) tool wear compensation strategies. Research efforts in this area have intensified over the last 20 years. However, most methods proposed were applicable only for a few work-tool combinations and in limited input process parametric settings. Instead of tool wear compensation, several research articles have focused on strategies to reduce the negative impact of tool wear on the quality of fabricated parts. The present study systematically reviews various investigations conducted in this area and aims to add cutting-edge compensation for tool wear to future inquiries. The articles reviewed here are explored in detail. Critical findings/innovations are classified into four categories: tool wear in µEDM, tool wear compensation techniques, and offline and online compensation methods.

3.
Heliyon ; 10(6): e27869, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533060

RESUMO

The present investigation focuses on assessing the water quality of groundwater surrounding brick kilns in the Jammu district of Jammu and Kashmir (J&K). At 43 different brick kiln sites in both north and south regions of Jammu, concentrations of heavy metals were measured using established techniques. The elements zinc, copper, iron, lead, cadmium, nickel, and manganese were analyzed utilizing an Atomic Absorption Spectrophotometer (AAS). The pollution load index value was consistently below unity across all sites, suggesting an absence of pollution and making the water suitable for consumption. The average concentrations, listed in ascending order, were found to be 0.38 mg/L for copper, 0.31 mg/L for zinc, 0.01 mg/L for iron, and 0.09 mg/L for manganese. Notably, concentrations of lead, cadmium, and nickel were found below the detectable levels. Evaluation of contamination factors revealed the sequence Cu > Fe > Zn > Mn, while the geo accumulation index followed the sequence Cu > Fe > Mn > Zn. Comparison of these findings with the established standards of World Health Organization and Bureau of Indian Standards indicated that the recorded ranges were within permissible limits. The study's outcomes suggest that heavy metal emissions from brick kilns may not significantly impact the quality of groundwater. Elevated copper levels found near brick kilns were likely to result from plumbing materials in the study area. Iron and manganese in groundwater seems to have geo-genic origin and not emission-related. This research represents a foundational step in examining groundwater contamination by heavy metals specifically in the neighborhood of brick kilns in Jammu district. It contributes to the establishment of a comprehensive database and serves as a reference point for future studies. Additionally, the study recommends regular monitoring of groundwater to ensure the maintenance of drinking water quality.

4.
Sci Rep ; 14(1): 6817, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514706

RESUMO

This work discusses selecting optimal brake friction composite alternatives based on an integrated MABAC (multi-attributive border approximation area comparison) and AHP (analytic hierarchy process) approach. Therefore, non-asbestos automotive brake friction composites containing varying proportions of cement dust (50 to 0 wt%) and barium sulfate (0 to 50 wt%) were developed and tribo-evaluated on a Krauss machine following European regulations. Composite made up of 30 wt% cement dust and 20 wt% barium sulfate had the highest friction coefficient (0.361), lowest variability coefficient (0.598), and maximum recovery (123.27%). The composite with the least fading (15.36%) included 50 wt% cement dust, whereas the composite with the lowest wear (9.10 g) and the least frictional fluctuations (0.271) contained 50 wt% barium sulfate. By AHP, the friction coefficient (0.1989), fade (0.1696), recovery (0.1551), and wear (0.1412) were selected as the essential criteria in the performance assessment. Based on the MABAC ranking evaluation, the composite comprises 20 wt% barium sulfate and 30 wt% cement dust has the best tribological profile, whereas the composites of solely cement dust or barium sulfate have the poorest tribological profile. The acquired ranking results were confirmed using other decision-making models and subjected to sensitivity analysis to demonstrate their robustness.

5.
Eur Biophys J ; 53(3): 147-157, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456905

RESUMO

Phosphopantetheine adenylyltransferase (EC. 2.7.7.3, PPAT) catalyzes the penultimate step of the multistep reaction in the coenzyme A (CoA) biosynthesis pathway. In this step, an adenylyl group from adenosine triphosphate (ATP) is transferred to 4'-phosphopantetheine (PNS) yielding 3'-dephospho-coenzyme A (dpCoA) and pyrophosphate (PPi). PPAT from strain C3 of Klebsiella pneumoniae (KpPPAT) was cloned, expressed and purified. It was crystallized using 0.1 M HEPES buffer and PEG10000 at pH 7.5. The crystals belonged to tetragonal space group P41212 with cell dimensions of a = b = 72.82 Å and c = 200.37 Å. The structure was determined using the molecular replacement method and refined to values of 0.208 and 0.255 for Rcryst and Rfree factors, respectively. The structure determination showed the presence of three crystallographically independent molecules A, B and C in the asymmetric unit. The molecules A and B are observed in the form of a dimer in the asymmetric unit while molecule C belongs to the second dimer whose partner is related by crystallographic twofold symmetry. The polypeptide chain of KpPPAT folds into a ß/α structure. The conformations of the side chains of several residues in the substrate binding site in KpPPAT are significantly different from those reported in other PPATs. As a result, the modes of binding of substrates, phosphopantetheine (PNS) and adenosine triphosphate (ATP) differ considerably. The binding studies using fluorescence spectroscopy indicated a KD value of 3.45 × 10-4 M for ATP which is significantly lower than the corresponding values reported for PPAT from other species.


Assuntos
Trifosfato de Adenosina , Klebsiella pneumoniae , Nucleotidiltransferases , Klebsiella pneumoniae/metabolismo , Cristalografia por Raios X , Coenzima A/química , Coenzima A/metabolismo
6.
Sci Rep ; 14(1): 3541, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347060

RESUMO

The importance of solar radiation for the body's ability to synthesize Vitamin D3 is well documented, yet the precise amount of sun exposure required to avoid Vitamin D insufficiency is less clear. To address this knowledge gap, this study sought to utilize the sun in a suitable period at the optimum dose by utilizing numerical simulations to determine the amount of Vitamin D3 synthesis in the skin according to season, time of day, and geographical location in Turkey. The study was carried out in three stages; in the first stage, daily, monthly, and annual values were determined in cases where the solar zenith angle has the active UV-B wavelength. The second stage determined the level of Vitamin D that can be synthesized in all skin types at 25% solar radiation exposure. In the third stage, the sun exposure time required for 1000 International Units (IU) for all skin types was calculated. According to the analysis, the yearly period of active synthesis of D3 on Earth lasts from the beginning of March to the third week of October. During the day, it is between 10:00 and 16:00. For 1000 IU/day, the average annual estimated times (minutes) are 5.05 for Type I, 6.3 for Type II, 7.6 for Type III, 11.35 for Type IV, 15.15 for Type V, and 25.25 for Type VI. The results of this paper will impact awareness for academic-medical users.


Assuntos
Colecalciferol , Raios Ultravioleta , Vitamina D , Luz Solar , Estações do Ano , Vitaminas
7.
Heliyon ; 10(3): e25453, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38352792

RESUMO

Multi-criteria decision-making (MCDM) methods have been widely used among researchers to provide a trade-off solution between best and worst, considering conflicting criteria and sets of preferences. An efficient and systematic literature review of these methods is needed to maintain their application in distinctive domains. To this end, this paper presents a comprehensive and systematic literature survey on "multi-objective optimization by ratio analysis" (MOORA) method and its fuzzy extensions developed and discussed in recent years. This review includes articles categorized based on the publication name, publishing year, journal name, type of applications, and type of fuzzy extensions. In addition, this review will enhance the understanding of practitioners and decision-makers on the MOORA method, its development, fuzzy hybridization, different application areas, and future work. The study revealed that the MOORA technique was predominantly used with the TOPSIS approach, followed by the AHP and COPRAS methods. Furthermore, 76.28 % use single and hybridization approaches among all MOORA studies, while 23.72 % use MOORA in a fuzzy environment.

8.
Sci Rep ; 14(1): 3140, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326386

RESUMO

Dissolved oxygen (DO) is an important parameter in assessing water quality. The reduction in DO concentration is the result of eutrophication, which degrades the quality of water. Aeration is the best way to enhance the DO concentration. In the current study, the aeration efficiency (E20) of various numbers of circular jets in an open channel was experimentally investigated for different channel angle of inclination (θ), discharge (Q), number of jets (Jn), Froude number (Fr), and hydraulic radius of each jet (HRJn). The statistical results show that jets from 8 to 64 significantly provide aeration in the open channel. The aeration efficiency and input parameters are modelled into a linear relationship. Additionally, utilizing WEKA software, three soft computing models for predicting aeration efficiency were created with Artificial Neural Network (ANN), M5P, and Random Forest (RF). Performance evaluation results and box plot have shown that ANN is the outperforming model with correlation coefficient (CC) = 0.9823, mean absolute error (MAE) = 0.0098, and root mean square error (RMSE) = 0.0123 during the testing stage. In order to assess the influence of different input factors on the E20 of jets, a sensitivity analysis was conducted using the most effective model, i.e., ANN. The sensitivity analysis results indicate that the angle of inclination is the most influential input variable in predicting E20, followed by discharge and the number of jets.

9.
Heliyon ; 10(3): e25015, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318078

RESUMO

The main objective of this work is to review the capability of using waste marble dust (MD) particles as reinforcing materials in recycled polymeric composites to achieve environmentally friendly materials. In the present study, polymer composites were fabricated from recycled polyethylene terephthalate (rPET) and MD and then analyzed for their structural and thermal properties. Preparation of rPET-based composites containing 0-20 wt% MD was carried out through extrusion and injection molding. For their characterization Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) were applied. The DSC analysis revealed a nucleating effect of MD on rPET, which was manifested in a higher crystallization temperature (196.7 °C ⇒ 204.4 °C); however, the marble particles were also found to hamper chain mobility, thereby decreasing the crystallinity ratio (23.7 % ⇒ 19.2 %) of rPET and altering its crystalline structure. According to the TGA measurements, a slight increase occurred in the thermal stability of rPET, its major decomposition temperature increased from 446 °C to 451 °C when 20 wt% MD was incorporated into it. DMA showed an improved stiffness in the entire investigated temperature range for MD-filled composites versus neat rPET. Additionally, several factors were derived from the DMA data, including the effectiveness factor, degree of entanglement, and reinforcing efficiency factor which all suggested a decent interaction between the components indicating a proper reinforcing ability of marble powder. However, above 5 wt% MD content the reinforcing efficiency deteriorated due to the agglomeration of filler particles, which was also supported by scanning electron microscopic images.

10.
Indian J Pathol Microbiol ; 66(4): 886-887, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084558

RESUMO

Ataxia-telangiectasia (A-T) is a rare autosomal recessive disease characterized by ataxia, cutaneous and ocular telangiectasia, impaired immunity with susceptibility to sino-pulmonary infections, radiation sensitivity, and cancers particularly of hemato-lymphoid origin. Liver function tests abnormalities and elevated alfa feto-protein have been reported in A-T; however, there is no reported case of combined hepatocellular-cholangiocarcinoma (cHCC-CC) in literature. These tumors should be treated in similar fashion as in general population; however, reduction of chemotherapy dose might be helpful in decreasing chemo-toxicity.


Assuntos
Ataxia Telangiectasia , Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Ataxia Telangiectasia/complicações , Ataxia Telangiectasia/diagnóstico , Ataxia Telangiectasia/patologia , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/diagnóstico , Estudos Retrospectivos , Ductos Biliares Intra-Hepáticos/patologia
11.
Cureus ; 15(9): e46252, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37908954

RESUMO

Background The WHO protocol for the management of shock in children with severe acute malnutrition (SAM) is not supported by physiological evidence. In this study, we aimed to assess the effectiveness of the WHO treatment protocol in the management of shock in children with SAM. Methodology This cohort study included children aged 2-60 months with WHO-defined SAM and fulfilling the WHO criteria for identification of shock. The exclusion criteria included severe anemia (hemoglobin <4 g/dL), congenital anomalies, congenital heart defects, and chronic diseases. The WHO treatment protocol for the management of shock was used, and features of resolution of shock were assessed at eight and 24 hours. Oliguria was recorded at eight and 24 hours along with in-hospital mortality. Multiple logistic regression was used to determine predictors of mortality. Results Of 53 children, 40 (75.4%) were discharged and 13 (24.5%) expired. We observed significant resolution of features of shock at 24 hours compared to eight hours (35 (71.4%) vs. 10 (18.8%), p < 0.0001). Further analysis revealed a significant resolution of features of shock (p = 0.03) at 24 hours in both fluid-responsive (24 vs. 10) and fluid-refractory children (11 vs. 27) compared to eight hours. Multivariate analysis revealed that mechanical ventilation was positively related to death (odds ratio (OR) = 85, 95% confidence interval (CI) = 8.49, 860, p < 0.0001), and inotrope scores <20 (OR = 0.053, 95% CI = 0.004, 0.64, p = 0.021) and blood transfusion (OR = 0.025, 95% CI = 0.001, 0.61, p = 0.024) had favorable outcomes. Conclusions The WHO protocol for the management of shock in children with SAM is effective in fluid-responsive shock whereas evidence was inconclusive in fluid-refractory shock.

12.
Sci Transl Med ; 15(718): eadh1469, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37851822

RESUMO

Leishmania braziliensis is a parasitic infection that can result in inflammation and skin injury with highly variable and unpredictable clinical outcomes. Here, we investigated the potential impact of microbiota on infection-induced inflammatory responses and disease resolution by conducting an integrated analysis of the skin microbiome and host transcriptome on a cohort of 62 patients infected with L. braziliensis. We found that overall bacterial burden and microbiome configurations dominated with Staphylococcus spp. were associated with delayed healing and enhanced inflammatory responses, especially by IL-1 family members. Quantification of host and bacterial transcripts on human lesions revealed that high lesional S. aureus transcript abundance was associated with delayed healing and increased expression of IL-1ß. This cytokine was critical for modulating disease outcomes in L. braziliensis-infected mice colonized with S. aureus, given that its neutralization reduced pathology and inflammation. These results highlight how the human microbiome can shape disease outcomes in cutaneous leishmaniasis and suggest pathways toward host-directed therapies to mitigate the inflammatory consequences.


Assuntos
Leishmaniose Cutânea , Microbiota , Humanos , Camundongos , Animais , Staphylococcus aureus , Multiômica , Inflamação , Bactérias , Gravidade do Paciente
13.
J Trop Pediatr ; 69(6)2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37805828

RESUMO

This prospective cross-sectional study evaluated the diagnostic and prognostic role of cerebrospinal fluid (CSF) tumor necrosis factor-alpha (TNF-α) in children with cerebral malaria (CM) and its role in the differentiation of CM from non-cerebral severe malaria. CSF TNF-α was measured using a human TNF-α enzyme-linked immunosorbent assay kit of 39 cases of CM and 19 cases of non-cerebral severe malaria. CSF TNF-α levels were significantly higher in CM (p < 0.001). Based on the receiver operating characteristics curve, a cutoff value of CSF TNF-α was 5.7 pg/ml for diagnosis of CM with sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 87.2%, 94.7%, 97.1% and 78.3% respectively. The cutoff value of CSF TNF-α was 13.7 pg/ml for predicting adverse outcomes in CM with sensitivity, specificity, PPV and NPV of 100%, 96.8%, 88.9% and 100%, respectively. However, the cutoff value of CSF TNF-α was 4.96 pg/ml for predicting adverse outcomes in non-cerebral severe malaria with a sensitivity, specificity, PPV and NPV of 100%, 94.1%, 88.9% and 100% respectively. So, CSF TNF-α is an excellent biomarker and can be used as a diagnostic and prognostic tool. More studies are needed to establish CSF TNF-α as a predictor of neurological sequelae.


Assuntos
Malária Cerebral , Fator de Necrose Tumoral alfa , Humanos , Criança , Fator de Necrose Tumoral alfa/líquido cefalorraquidiano , Malária Cerebral/diagnóstico , Malária Cerebral/líquido cefalorraquidiano , Estudos Prospectivos , Estudos Transversais , Curva ROC
14.
Bioinformation ; 19(4): 392-398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822814

RESUMO

The identification and characterization of plasma proteins in drug resistant and drug sensitive in HIV-1 infected/AIDS patients were carried out using the SWATH-MS protocol. In total, 204 proteins were identified and quantified, 57 proteins were differentially expressed, out of which 25 proteins were down regulated and 32 proteins were up regulated in drug resistant patients. Six proteins such as complement C4-A, immunoglobulin heavy variable 1-2, carboxylic ester hydrolase, fibulin-1, immunoglobulin lambda constant7, secreted phosphoprotein 24 were differentially expressed in individuals with drug resistant HIV as compared to individuals with drug sensitive HIV. Gene ontology of 57 differentially expressed proteins was analysed and documented.

15.
J Exp Med ; 220(12)2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37812390

RESUMO

Cutaneous leishmaniasis causes alterations in the skin microbiota, leading to pathologic immune responses and delayed healing. However, it is not known how these microbiota-driven immune responses are regulated. Here, we report that depletion of Foxp3+ regulatory T cells (Tregs) in Staphylococcus aureus-colonized mice resulted in less IL-17 and an IFN-γ-dependent skin inflammation with impaired S. aureus immunity. Similarly, reducing Tregs in S. aureus-colonized and Leishmania braziliensis-infected mice increased IFN-γ, S. aureus, and disease severity. Importantly, analysis of lesions from L. braziliensis patients revealed that low FOXP3 gene expression is associated with high IFNG expression, S. aureus burden, and delayed lesion resolution compared to patients with high FOXP3 expression. Thus, we found a critical role for Tregs in regulating the balance between IL-17 and IFN-γ in the skin, which influences both bacterial burden and disease. These results have clinical ramifications for cutaneous leishmaniasis and other skin diseases associated with a dysregulated microbiome when Tregs are limited or dysfunctional.


Assuntos
Leishmaniose Cutânea , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Staphylococcus aureus , Interleucina-17 , Linfócitos T Reguladores , Gravidade do Paciente , Fatores de Transcrição Forkhead
16.
J Cancer Res Clin Oncol ; 149(19): 16983-16992, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37740764

RESUMO

PURPOSE: This study aimed to evaluate the survival outcomes and identify prognostic factors for patients with oral cavity cancer (OCC) who underwent adjuvant treatment with volumetric arc therapy (VMAT) using simultaneous integrated boost (SIB). METHODS: Data was collected for post-operated patients of carcinoma of oral cavity who received adjuvant VMAT with SIB between June 2018 and December 2022. The data was entered and analyzed using SPSS software version 20.0. Survival rates were estimated using Kaplan Meier method. To determine survival difference between the groups, log rank test was used. Multivariate analyses were performed with Cox proportional hazard model and p value < 0.05 was considered as significant. RESULTS: A total of 178 patients were included in the study. The median follow-up period was 26 months (range 3-56 months). The 3-year OS, DFS, and LRC rates were 78% (95% CI 77-79%), 76% (95% CI 74-77%), and 81% (95% CI 80-82%), respectively. Univariate analysis identified age ≥ 50 years, lymph node involvement, extracapsular extension (ECE), and N2-N3 disease as significant adverse prognostic factors for OS, DFS, and LRC. Multivariate analysis confirmed age ≥ 50 years and nodal involvement as independent predictors of worse OS, DFS, and LRC. Additionally, ECE independently affected OS and DFS. CONCLUSION: Adjuvant treatment with VMAT using SIBin patients with OCC is effective. Age and nodal involvement had significant impact on LRC, DFSand OS while ECE on DFSand OS.


Assuntos
Neoplasias Bucais , Humanos , Pessoa de Meia-Idade , Prognóstico , Neoplasias Bucais/radioterapia , Terapia Combinada , Modelos de Riscos Proporcionais , Estudos Retrospectivos
17.
RSC Adv ; 13(36): 25253-25275, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37622026

RESUMO

In 21st century, the energy demand has grown incredibly due to globalization, human population explosion and growing megacities. This energy demand is being mostly fulfilled by fossil-based sources, which are non-renewable and a major cause of global warming. Energy from these fossil-based sources is cheaper, however challenges exist in terms of climate change. This makes renewable energy sources more promising and viable for the future. Hydrogen is a promising renewable energy carrier for fulfilling the increasing energy demand due to its high energy density, non-toxic and environment friendly characteristics. It is a non-toxic energy carrier as combustion of hydrogen produces water as the byproduct whereas other conventional fuels produce harmful gases and carcinogens. Because of its lighter weight, hydrogen leaks are also easily dispersed in the atmosphere. Hydrogen is one of the most abundant elements on Earth, yet it is not readily available in nature like other fossil fuels. Hence, it is a secondary energy source and hydrogen needs to be produced from water or biomass-based feedstock for it to be considered renewable and sustainable. This paper reviews the renewable hydrogen generation pathways such as water splitting, thermochemical conversion of biomass and biological conversion technologies. Purification and storage technologies of hydrogen is also discussed. The paper also discusses the hydrogen economy and future prospects from an Indian context. Hydrogen purification is necessary because of high purity requirements in particular applications like space, fuel cells etc. Various applications of hydrogen are also addressed and a cost comparison of various hydrogen generation technologies is also analyzed. In conclusion, this study can assist researchers in getting a better grasp of various renewable hydrogen generation pathways, it's purification and storage technologies along with applications of hydrogen in understanding the hydrogen economy and its future prospect.

19.
J Cancer Res Clin Oncol ; 149(13): 12355-12364, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37434094

RESUMO

INTRODUCTION: The standard of care for treating early invasive cervical cancer is radical hysterectomy or radiation alone while chemo-radiation is a definitive treatment for advanced disease. Occasionally, a simple hysterectomy is performed in the cancer cervix and these patients merit adjuvant treatment in view of the high chances of loco-regional recurrences. The aim of the study was to analyze the survival outcome of these patients treated with salvage chemo-radiotherapy and also to determine the prognostic factors affecting survival. MATERIALS AND METHODS: The medical records of all patients with cervical cancer post simple hysterectomy outside and who received salvage treatment in our department between 2014 and 2020 were retrieved. The data regarding clinical, treatment details and survival were analyzed. RESULTS: A total of 198 patients were included. Median follow-up duration was 45.5 months. Gross disease and lymphadenopathy were seen in 60% and 28% patients, respectively. The 5-year progression-free survival(PFS) and overall survival(OS) was 75% and 76%, respectively. Concurrent chemotherapy alone or in combination with induction chemotherapy using three-drug regimens showed better survival compared to those treated by radiation alone. On multivariate analysis, factors found to be adversely affecting OS and PFS were lymph node (LN) size of more than 2 cm, non-squamous histology, overall treatment time(OTT) of more than 12 weeks and use of non three-drug chemotherapy regimen. CONCLUSION: Subtotal hysterectomy results in a higher incidence of local recurrence of disease. Factors that impair the outcome in this sub-group of patients are gross lymphadenopathy, non-squamous histology and prolong OTT.


Assuntos
Linfadenopatia , Neoplasias do Colo do Útero , Feminino , Humanos , Prognóstico , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Colo do Útero/patologia , Histerectomia , Linfadenopatia/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Intervalo Livre de Doença
20.
J Inorg Biochem ; 247: 112311, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37421730

RESUMO

Lactoperoxidase (LPO) is a heme containing mammalian enzyme which uses hydrogen peroxide (H2O2) to catalyze the conversion of substrates into oxidized products. LPO is found in body fluids and tissues such as milk, saliva, tears, mucosa and other body secretions. The previous structural studies have shown that LPO converts substrates, thiocyanate (SCN-) and iodide (I-) ions into oxidized products, hypothiocyanite (OSCN-) and hypoiodite (IO-) ions respectively. We report here a new structure of the complex of LPO with an oxidized product, nitrite (NO2-). This product was generated from NO using the two step reaction of LPO by adding hydrogen peroxide (H2O2) in the solution of LPO in 0.1 M phosphate buffer at pH 6.8 as the first step. In the second step, NO gas was added to the above mixture. This was crystallized using 20% (w/v) PEG-3350 and 0.2 M ammonium iodide at pH 6.8. The structure determination showed the presence of NO2- ion in the distal heme cavity of the substrate binding site of LPO. The structure also showed that the propionate group which is linked to pyrrole ring D of the heme moiety was disordered. Similarly, the side chain of Asp108, which is covalently linked to heme moiety, was also split into two components. As a result of these changes, the conformation of the side chain of Arg255 was altered allowing it to form new interactions with the disordered carboxylic group of propionate moiety. These structural changes are indicative of an intermediate state in the catalytic reaction pathway of LPO.


Assuntos
Lactoperoxidase , Nitritos , Animais , Lactoperoxidase/química , Nitritos/metabolismo , Óxido Nítrico/metabolismo , Peróxido de Hidrogênio/metabolismo , Dióxido de Nitrogênio/metabolismo , Propionatos , Mamíferos/metabolismo , Heme/química
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