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1.
Int J Biol Macromol ; 281(Pt 2): 136291, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39368573

RESUMEN

Malaria remains a global health issue, especially in resource-limited regions. Artemisinin, a key antimalarial compound from Artemisia annua, is crucial for treatment, but low natural yields hinder large-scale production. In this study, we employed advanced transgenic technology to co-overexpress six key biosynthetic enzymes-Isopentenyl Diphosphate Isomerase (IDI), Farnesyl Pyrophosphate Synthase (FPS), Amorpha 4,11-diene Synthase (ADS), cytochrome P450 monooxygenase (CYP71AV1), cytochrome P450 oxidoreductase (AACPR) and artemisinic aldehyde D11 reductase (DBR2)-in A. annua to significantly enhance artemisinin production. Our innovative approach utilized a co-expression strategy to optimize the artemisinin biosynthetic pathway, leading to a remarkable up to 200 % increase in artemisinin content in T1 transgenic plants compared to non-transgenic controls. The stability and efficacy of this transformation were confirmed in subsequent generations (T2), achieving a potential 232 % increase in artemisinin levels. Additionally, we optimized transgene expression to maintain plant growth and development, and performed untargeted metabolite analysis using GC-MS, which revealed significant changes in metabolite composition among T2 lines, indicating effective diversion of farnesyl diphosphate into the artemisinin pathway. This metabolic engineering breakthrough offers a promising and scalable solution for enhancing artemisinin production, representing a major advancement in the field of plant biotechnology and a potential strategy for more cost-effective malaria treatment.

2.
J Assoc Physicians India ; 72(9S): 27-31, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39291570

RESUMEN

Torsemide is a loop diuretic used to manage edema associated with chronic kidney disease (CKD) and acute kidney injury (AKI). It acts by inhibiting sodium and chloride ions reabsorption in the ascending limb of the loop of Henle, thereby increasing urine output and reducing fluid accumulation. Compared to other diuretics, torsemide has an extended duration of action, higher bioavailability, and its elimination route is primarily through the hepatic route, making it effective in patients with CKD and AKI. Clinical studies indicate that torsemide can improve symptoms of fluid overload and potentially enhance renal function.


Asunto(s)
Edema , Insuficiencia Renal Crónica , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico , Torasemida , Humanos , Lesión Renal Aguda/complicaciones , Lesión Renal Aguda/tratamiento farmacológico , Edema/etiología , Edema/tratamiento farmacológico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/farmacología , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/uso terapéutico , Torasemida/farmacología , Torasemida/uso terapéutico
3.
ISA Trans ; 153: 41-56, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39084912

RESUMEN

This paper proposes a novel controller design using adaptation based modified super twisting control to facilitate trajectory tracking and hovering maneuvers for the quadrotor. The controller gains of the existing modified super twisting control require bounds on the disturbance for trajectory tracking and hovering of the quadrotor. In this paper, the controller gains are adapted using the proposed dynamic adaptation law without knowing the actual disturbance or their upper bounds. The controller is designed within a nonlinear framework without performing linearization of quadrotor dynamics, which enables the proposed controller to remain effective even when the states deviate significantly from their nominal values. The performance of trajectory tracking and hovering of the quadrotor in the presence of disturbance is demonstrated using numerical simulations. In order to assess the effectiveness of the controller, the performance of the adaptation based modified super twisting control is compared to the existing modified super twisting control, and the proposed controller outperforms the existing one.

4.
Chem Commun (Camb) ; 60(60): 7761-7764, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38973622

RESUMEN

Among the several unsymmetrical bis-NHC derived distinct homo-bimetallic and mono-NHC supported PdII complexes studied here (1-5), the bimetallic complex 1 was noted to be the most effective catalyst for the challenging hydrodefluorination. The electron richness of the metal centers and the synergistic cooperation between the PdII centers (cooperativity index, ɑ = 8.67) have been recognized to be the deciding factor for its better activity.

5.
Cureus ; 16(5): e61261, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38939296

RESUMEN

Aim We reviewed surgical outcomes for patients with colorectal cancer resections in Basildon and Thurrock University Hospital between April 2019 and March 2020. Methods Clinical characteristics of 141 patients who underwent surgical resection for colorectal cancer at the district hospital were assessed and reported, including tumor site, disease stage, and type of surgical resection performed. We reviewed 30- and 90-day postoperative mortality, postoperative complications, return to the theater, and extended hospital stay data for these patients. The results of our review across measured outcomes were compared to the national average from the National Bowel Cancer Audit (NBOCA) Report. Results Clinical data and health outcomes for 141 patients with colorectal cancer resections within the index year were reviewed. The mean age at diagnosis was 68.9 (12.5) years. Among the patients, 61 (43.3%) were female, and 59 (41.8%) had Stage III and IV colorectal cancer. Around 95 (67.4%) had the colon as the primary tumor site, while 46 (32.6%) had the primary tumor site in the rectum. Of the patients, 17 (12.1%) had emergency surgeries, and 124 (87.9%) underwent laparoscopic surgery. Right hemicolectomy was the most common operation performed in 58 patients (41.1%). The average length of stay was 7.8 (6.6) days; the length of stay was similar for both colonic and rectal resections. Low 30-day and 90-day mortality rates of (1/141) 0.71% and (2/141) 1.4%, respectively, were observed compared to the 90-day United Kingdom (UK) national average mortality rate of 2.7% in 2019/20. Around 30 (21.3%) of the patients developed postoperative complications within 30 days of surgery. Only six out of 30 postoperative complications were classified as Clavien-Dindo Grade III. Conclusion Surgical outcomes for patients with colorectal cancer in our district general hospital are similar to or lower than the national averages estimated by NBOCA. To further strengthen surgical care delivery and improve patient outcomes in the United Kingdom, there is a need to improve surgical techniques and quality improvement processes.

6.
Cureus ; 16(4): e58438, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38765387

RESUMEN

Introduction Gallstone ileus is an uncommon cause of small bowel obstruction; it is a rare complication of calculus chronic cholecystitis which leads to cholecystoenteric fistula and impaction of gallstone in the gastrointestinal tract leading to mechanical bowel obstruction. Our aim is to report the natural history and management of this rare condition in a teaching hospital. Materials and methods It is a retrospective study, where 10 years of data related to the management of intestinal obstruction secondary to gallstone ileus was collected. The cohort included 10 patients, whose demographic data, clinical findings, and management outcomes were evaluated. Results Majority of patients were female (90%, n=9) with a median of 83 years (range 61-96) although 90% of the population were above 70 years. Presenting complaints were mostly pain and vomiting. The onset of symptoms was between two and seven days. The site of obstruction was mostly the ileum (n=9) with the exception of one case in the sigmoid proximal to a benign stricture, and the size of the stone ranged from 2.5 to 4 cm. Moreover, most of the patients had a previous history of gallstone (n=7) with one post-cholecystectomy status. The laboratory investigations in 50% of patients had deranged liver function test (LFT) and acute kidney injury (AKI), and 60% had raised inflammatory markers, namely, white blood cells (WBC) and C-reactive protein (CRP). Intervention as enterolithotomy was the preferred approach (n=8 (two laparoscopic, six open surgery)), and two patients were managed conservatively. The mean postoperative length of stay was 10 days in the open approach and five days in the laparoscopic approach, respectively. Conclusions Elderly female patients are more prone to have gallstone ileus particularly with a past medical history of gallstones, and the preferred management option is enterolithotomy which could be open or laparoscopic depending on the expertise of the surgeon.

7.
Parasite Immunol ; 46(5): e13036, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720445

RESUMEN

Apolipoprotein E (ApoE) has been associated with several diseases including Parkinson's disease, Alzheimer's and multiple sclerosis. ApoE also has documented immunomodulatory functions. We investigated gene expression in circulating monocytes and in bone marrows of patients with visceral leishmaniasis (VL) living in an endemic area in Bihar, India, and contrasted these with control healthy subjects or other diagnostic bone marrows from individuals in the same region. Samples from VL patients were obtained prior to initiating treatment. Our study revealed significant upregulated expression of the apoE transcript in patients with VL. Furthermore, the levels of ApoE protein were elevated in serum samples of subjects with VL compared with healthy endemic controls. These observations may provide clues regarding the complex interactions between lipid metabolism and immunoregulation of infectious and inflammatory diseases.


Asunto(s)
Apolipoproteínas E , Leishmaniasis Visceral , Monocitos , Regulación hacia Arriba , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Apolipoproteínas E/genética , Médula Ósea , India/epidemiología , Leishmaniasis Visceral/inmunología , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/parasitología , Monocitos/inmunología
8.
Cureus ; 16(4): e58901, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38800329

RESUMEN

Most obturator hernias are diagnosed intraoperatively due to their vague signs and symptoms. However, they are associated with a high mortality rate mainly because of the patient's age, comorbidities, and late diagnosis. We present three cases of obturator hernia in patients admitted under our care with signs of acute intestinal obstruction. All the patients were elderly with comorbidities, and they underwent open surgery with anatomical repair of the hernial defect with or without resection of any gangrenous bowel. They were discharged in good health, and during the limited follow-up period, there has been no recurrence. We would like to emphasize that obturator hernia should be considered in the differential diagnosis when an elderly, thinly built woman presents with acute intestinal obstruction. Though the outcome of such cases depends on the clinical status and comorbidities of the patient, early diagnosis and treatment can help in reducing postoperative morbidity and mortality.

9.
PLoS Negl Trop Dis ; 18(2): e0011960, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38408097

RESUMEN

BACKGROUND: CD4+ T cells play a central role in control of L. donovani infection, through IFN-γ production required for activation of macrophages and killing of intracellular parasites. Impaired control of parasites can in part be explained by hampered CD4+ T cells effector functions in visceral leishmaniasis (VL) patients. In a recent studies that defined transcriptional signatures for CD4+ T cells from active VL patients, we found that expression of the IL-7 receptor alpha chain (IL-7Rα; CD127) was downregulated, compared to CD4+ T cells from endemic controls (ECs). Since IL-7 signaling is critical for the survival and homeostatic maintenance of CD4+ T cells, we investigated this signaling pathway in VL patients, relative to ECs. METHODS: CD4+ T cells were enriched from peripheral blood collected from VL patients and EC subjects and expression of IL7 and IL7RA mRNA was measured by real time qPCR. IL-7 signaling potential and surface expression of CD127 and CD132 on CD4+ T cell was analyzed by multicolor flow cytometry. Plasma levels of soluble IL-7 and sIL-7Rα were measured by ELISA. RESULT: Transcriptional profiling data sets generated previously from our group showed lower IL7RA mRNA expression in VL CD4+ T cells as compared to EC. A significant reduction was, however not seen when assessing IL7RA mRNA by RT-qPCR. Yet, the levels of soluble IL-7Rα (sIL-7Rα) were reduced in plasma of VL patients compared to ECs. Furthermore, the levels of soluble IL-7 were higher in plasma from VL patients compared to ECs. Interestingly, expression of the IL-7Rα protein was higher on VL patient CD4+ T cells as compared to EC, with activated CD38+ CD4+ T cells showing higher surface expression of IL-7Rα compared to CD38- CD4+ T cells in VL patients. CD4+ T cells from VL patients had higher signaling potential baseline and after stimulation with recombinant human IL-7 (rhIL-7) compared to EC, as measured by phosphorylation of STAT5 (pSTAT5). Interestingly, it was the CD38 negative cells that had the highest level of pSTAT5 in VL patient CD4+ T cells after IL-7 stimulation. Thus, despite unaltered or potentially lowered IL7RA mRNA expression by CD4+ T cells from VL patients, the surface expression of the IL-7Rα was higher compared to EC and increased pSTAT5 was seen following exposure to rhIL-7. Accordingly, IL-7 signaling appears to be functional and even enhanced in VL CD4+ T cells and cannot explain the impaired effector function of VL CD4+ T cells. The enhanced plasma IL-7 may serve as part of homeostatic feedback mechanism regulating IL7RA expression in CD4+ T cells.


Asunto(s)
Linfocitos T CD4-Positivos , Leishmaniasis Visceral , Humanos , Interleucina-7 , Leishmaniasis Visceral/parasitología , Transducción de Señal , ARN Mensajero/genética
10.
Sci Rep ; 13(1): 21021, 2023 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-38030709

RESUMEN

Pancreatic Neuroendocrine tumors (PanNET) are challenging to diagnose and often detected at advanced stages due to a lack of specific and sensitive biomarkers. This study utilized proteomics as a valuable approach for cancer biomarker discovery; therefore, mass spectrometry-based proteomic profiling was conducted on plasma samples from 12 subjects (3 controls; 5 Grade I, 4 Grade II PanNET patients) to identify potential proteins capable of effectively distinguishing PanNET from healthy controls. Data are available via ProteomeXchange with the identifier PXD045045. 13.2% of proteins were uniquely identified in PanNET, while 60% were commonly expressed in PanNET and controls. 17 proteins exhibiting significant differential expression between PanNET and controls were identified with downstream analysis. Further, 5 proteins (C1QA, COMP, HSP90B1, ITGA2B, and FN1) were selected by pathway analysis and were validated using Western blot analysis. Significant downregulation of C1QA (p = 0.001: within groups, 0.03: control vs. grade I, 0.0013: grade I vs. grade II) and COMP (p = 0.011: within groups, 0.019: control vs grade I) were observed in PanNET Grade I & II than in controls. Subsequently, ELISA on 38 samples revealed significant downregulation of C1QA and COMP with increasing disease severity. This study shows the potential of C1QA and COMP in the early detection of PanNET, highlighting their role in the search for early-stage (Grade-I and Grade-II) diagnostic markers and therapeutic targets for PanNET.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Proteómica , Detección Precoz del Cáncer , Biomarcadores de Tumor/análisis
12.
Chemistry ; 29(65): e202302180, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37702918

RESUMEN

The bis(azolium) salt [L1-H2 ]Br2 was found to serve as a suitable platform for accessing the heterobimetallic IrIII -M (M=PdII /AuI ) and PdII -IrIII complexes. Initially, selective mono-metalation of [L1-H2 ]Br2 yielded an orthometalated IrIII - or non-orthometalated PdII -complex. Sequential metalation of the mono-IrIII complex resulted in the formation of heterobimetallic IrIII -PdII /AuI complexes. Similarly, a distinct heterobimetallic PdII -IrIII complex was synthesized starting from the mono-PdII complex. Further, the corresponding homobimetallic IrIII -IrIII and PdII -PdII complexes were directly obtained from [L1-H2 ]Br2 . Additionally, monometallic PdII and IrIII analogues were synthesized from [L2-H]Br and [L3-H]Br, respectively. The heterobimetallic IrIII -PdII and PdII -IrIII complexes were then evaluated as catalysts in various one-pot tandem catalytic reactions in which they demonstrated superior activity than the mixtures of both their corresponding homobimetallic IrIII -IrIII /PdII -PdII and monometallic IrIII /PdII counterparts, under the constant concentrations of metal centers. Moreover, while comparing complexes IrIII -PdII and PdII -IrIII , the former exhibits higher activity in all the studied reactions. All these findings suggest the presence of some form of cooperativity between the two metal centers (Ir and Pd) connected by a single ligand framework in IrIII -PdII and PdII -IrIII complex, with IrIII -PdII displaying better cooperativity that has been validated by electrochemical, NMR, and DFT studies.

13.
Front Immunol ; 14: 1236952, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37638047

RESUMEN

Visceral leishmaniasis (VL) is a severe and often fatal form of leishmaniasis caused by Leishmania donovani in the Indian sub-continent. Post Kala-azar Dermal Leishmaniasis (PKDL) is a late cutaneous manifestation of VL, typically occurring after apparent cure of VL, but sometimes even without a prior history of VL in India. PKDL serves as a significant yet neglected reservoir of infection and plays a crucial role in the transmission of the disease, posing a serious threat to the VL elimination program in the Indian sub-continent. Therefore, the eradication of PKDL should be a priority within the current VL elimination program aimed at achieving a goal of less than 1 case per 10,000 in the population at the district or sub-district levels of VL endemic areas. To accomplish this, a comprehensive understanding of the pathogenesis of PKDL is essential, as well as developing strategies for disease management. This review provides an overview of the current status of diagnosis and treatment options for PKDL, highlighting our current knowledge of the immune responses underlying disease development and progression. Additionally, the review discusses the impact of PKDL on elimination programs and propose strategies to overcome this challenge and achieve the goal of elimination. By addressing the diagnostic and therapeutic gaps, optimizing surveillance and control measures, and implementing effective intervention strategies, it is possible to mitigate the burden of PKDL and facilitate the successful elimination of VL in the Indian sub-continent.


Asunto(s)
Leishmania donovani , Leishmaniasis Visceral , Humanos , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/epidemiología , Pueblo Asiatico , Manejo de la Enfermedad , India/epidemiología
14.
J Org Chem ; 88(13): 8690-8702, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37367717

RESUMEN

The hydrogenation of nitro compounds to their corresponding amines is developed using a heterogeneous and recyclable catalyst (V2O5/TiO2) under irradiation of blue LED (9 W) at ambient temperature. Hydrazine hydrate is used as a reductant and ethanol is used as a solvent, facilitating green, sustainable, low-cost production. The synthesis of 32 (hetero)arylamines and their pharmaceutically relevant molecules (five) are described. Significant features of the protocol include catalyst recyclability, green solvent, ambient temperature, and gram-scale reactions. Among the other aspects studied are 1H-NMR-assisted reaction progress monitoring, control experiments for mechanistic studies, protocol applications, and recyclability studies. Furthermore, the developed protocol enabled wide functional group tolerance, chemo-selectivity, high yield, and low-cost, sustainable, and environmentally benign synthesis.

15.
Plant Sci ; 334: 111736, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37211221

RESUMEN

The tomato is well-known for its anti-oxidative and anti-cancer properties, and with a wide range of health benefits is an important cash crop for human well-being. However, environmental stresses (especially abiotic) are having a deleterious effect on plant growth and productivity, including tomato. In this review, authors describe how salinity stress imposes risk consequences on growth and developmental processes of tomato through toxicity by ethylene (ET) and cyanide (HCN), and ionic, oxidative, and osmotic stresses. Recent research has clarified how salinity stress induced-ACS and - ß-CAS expressions stimulate the accumulation of ET and HCN, wherein the action of salicylic acid (SA),compatible solutes (CSs), polyamines (PAs) and ET inhibitors (ETIs) regulate ET and HCN metabolism. Here we emphasize how ET, SA and PA cooperates with mitochondrial alternating oxidase (AOX), salt overly sensitive (SOS) pathways and the antioxidants (ANTOX) system to better understand the salinity stress resistance mechanism. The current literature evaluated in this paper provides an overview of salinity stress resistance mechanism involving synchronized routes of ET metabolism by SA and PAs, connecting regulated network of central physiological processes governing through the action of AOX, ß-CAS, SOS and ANTOX pathways, which might be crucial for the development of tomato.


Asunto(s)
Etilenos , Estrés Salino , Solanum lycopersicum , Etilenos/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiología , Estrés Salino/fisiología
16.
Bioorg Med Chem Lett ; 88: 129308, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37127102

RESUMEN

To overcome the antibiotic resistance challenge, we synthesized a novel class of conjugates based on ciprofloxacin and avibactam, covalently linked by diverse amino acids. In vitro studies of these conjugates have shown improved antibacterial efficacy of avibactam when used alone against some ESKAPE pathogens, i.e., S. aureus, E. coli, and A. baumannii. Further, ceftazidime was screened in combination with all conjugates and found to be less synergistically effective than avibactam-ceftazidime co-dosing against K. pneumoniae and E. coli bacterial strains. Subsequently, the top-ranked active conjugates were investigated against the commercially available ß-lactamase-II (Penicillinase from Bacillus cereus) through in vitro studies. These studies elucidated two conjugates i.e, 9 (IC50 = 1.69±0.35 nM) and 24b (IC50 = 57.37±5.39 nM), which have higher inhibition profile than avibactam (IC50 = 141.08±12.20 nM). These outcomes allude to avibactam integration with ciprofloxacin is a novel and fruitful approach to discovering clinically valuable next-generation non-ß-lactam-ß-lactamase inhibitors.


Asunto(s)
Ceftazidima , Inhibidores de beta-Lactamasas , Ceftazidima/farmacología , Inhibidores de beta-Lactamasas/farmacología , Ciprofloxacina/farmacología , Lactamas/farmacología , Escherichia coli , Staphylococcus aureus/metabolismo , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Compuestos de Azabiciclo/farmacología , Compuestos de Azabiciclo/metabolismo , Combinación de Medicamentos , Klebsiella pneumoniae , Pruebas de Sensibilidad Microbiana
17.
J Biomol Struct Dyn ; 41(21): 12363-12371, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36744540

RESUMEN

Maintaining the protein stability upon mutation is a challenging task in protein engineering. In the present computational study, we induced a single point Gly100Ala mutation in SazCA and examined the factors governing the stability and flexibility of the mutated form, and compared it to that of the wildtype using molecular dynamics simulations. We observed higher structural stability and lesser residual mobility in the mutated SazCA. Improved H-bonding due to Gly100Ala was observed. Ala100 was responsible for the increased helical contents in the mutated SazCA while Gly100 compromised the secondary structure contents in the wildtype. A strong network of salt bridges and high local ordering of the solvent molecules at the protein surface contributed to the enhanced stability of the mutated protein. Our simulations conclusively highlight Gly100Ala mutation as a step towards designing a more robust and thermostable SazCA.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Bacterias , Simulación de Dinámica Molecular , Secuencia de Aminoácidos , Ingeniería de Proteínas , Mutación , Estabilidad de Enzimas
18.
Phys Chem Chem Phys ; 25(4): 3472-3484, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36637052

RESUMEN

Orotate phosphoribosyltransferase (OPRT) catalyses the reversible phosphoribosyl transfer from α-D-5-phosphoribosyl-1-pyrophosphate (PRPP) to orotic acid (OA) to yield orotidine 5'-monophosphate (OMP) during the de novo synthesis of nucleotides. Numerous studies have reported the inhibition of this reaction as a strategy to check diseases like tuberculosis, malaria and cancer. Insight into the inhibition of this reaction is, therefore, of urgent interest. In this study, we implemented a QM/MM framework on OPRT derived from Saccharomyces cerevisiae to obtain insights into the competitive binding of OA and OA-mimetic inhibitors by quantifying their interactions with OPRT. 4-Hydroxy-6-methylpyridin-2(1H) one showed the best inhibiting activity among the structurally similar OA-mimetic inhibitors, as quantified from the binding energetics. Our analysis of protein-ligand interactions unveiled the association of this inhibitory ligand with a strong network of hydrogen bonds, a large contribution of hydrophobic contacts, and bridging water molecules in the binding site. The ortho-substituted CH3 group in the compound resulted in a large population of π-electrons in the aromatic ring of this inhibitor, supporting the ligand binding further.


Asunto(s)
Orotato Fosforribosiltransferasa , Ácido Orótico , Ácido Orótico/metabolismo , Ligandos , Orotato Fosforribosiltransferasa/química , Orotato Fosforribosiltransferasa/metabolismo , Sitios de Unión
19.
J Biomol Struct Dyn ; 41(13): 6001-6010, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35862658

RESUMEN

The fastest member of the carbonic anhydrase family catalysing the reversible hydration of carbon dioxide to bicarbonate ions has been recently reported to be SazCA. While thermostable, this enzyme shows exceptional activity at 353 K for the reaction. This study explores the molecular basis for the exceptional activity of SazCA, in contrast to SspCA, probed using molecular dynamics simulations. Our simulations, carried out at different temperatures, indicate the presence of efficient proton shuttle between the active zinc centre and His64 residue in the two enzymes. The proton accepting His64 residue was identified to have in and out conformations with the in conformations being supportive to proton acceptance. Our simulations show a large population of in conformations in SazCA making the enzyme exhibit an exceptional activity. The RMSF and H-bonds analysis confirmed the role of His2 and His207 in supporting the attainment of in conformations in SazCA resulting in exceptional activity.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Anhidrasas Carbónicas , Protones , Dióxido de Carbono , Catálisis , Cinética
20.
Biomedicines ; 10(9)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36140268

RESUMEN

Any type of brain injury that transpires post-birth is referred to as Acquired Brain Injury (ABI). In general, ABI does not result from congenital disorders, degenerative diseases, or by brain trauma at birth. Although the human brain is protected from the external world by layers of tissues and bone, floating in nutrient-rich cerebrospinal fluid (CSF); it remains susceptible to harm and impairment. Brain damage resulting from ABI leads to changes in the normal neuronal tissue activity and/or structure in one or multiple areas of the brain, which can often affect normal brain functions. Impairment sustained from an ABI can last anywhere from days to a lifetime depending on the severity of the injury; however, many patients face trouble integrating themselves back into the community due to possible psychological and physiological outcomes. In this review, we discuss ABI pathologies, their types, and cellular mechanisms and summarize the therapeutic approaches for a better understanding of the subject and to create awareness among the public.

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