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1.
Inorg Chem ; 63(13): 5972-5981, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502785

RESUMO

Laves phases AB2 form the most abundant group of intermetallic compounds, consisting of combinations of larger electropositive metals A with smaller metals B. Many practical applications of Laves phases depend on the ability to tune their physical properties through appropriate substitution of either the A or B component. Although simple geometrical and electronic factors have long been thought to control the formation of Laves phases, no single factor alone can make predictions accurately. Several machine learning models have been developed to discover new Laves phases, including variations caused by solid solubility, using elemental properties solely on the basis of chemical composition. These models were trained on a data set comprising about 3700 entries of experimentally known phases AB2 with Laves and non-Laves structures. Among these models, a decision tree algorithm gave very good performance (average recall of 95%, precision of 94%, and accuracy of 96% on the test set) by using only a small set of descriptors, the most important of which relates to the electron density at the boundary of the Wigner-Seitz cell for the B component. This model provides guidance for new experiments by making predictions on >400000 candidates very quickly. A chemically unintuitive candidate Cd(Cu1-xSbx)2 with a limited solid solubility of Sb for Cu was targeted; it was successfully synthesized and confirmed to adopt a cubic MgCu2-type Laves structure.

2.
Molecules ; 29(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38398637

RESUMO

Several types of pollutants have acute adverse effects on living bodies, and the effective removal of these pollutants remains a challenge. Safranin O (a biological dye) and merbromin (a topical mercury-containing antiseptic) are considered organic pollutants, and there are only a few reports on their removal. Synthesized and well-characterized (through PXRD, FTIR, FESEM, and EDS analysis) MOF-5 was used for the first time in the removal of safranin O and merbromin from simulated wastewater and real wastewater. In both cases, MOF-5 effectively removed contaminants. We found that in simulated wastewater, the highest efficiency of removal of safranin O was 53.27% (for 15 mg/L) at pH 10, and for merbromin, it was 41.49% (for 25 mg/L) at pH 6. In the case of real wastewater containing natural ions (Na+, K+, F-, Cl-, SO42-, PO43-, Mg2+, and Ca2+) and other molecules, the removal efficiencies of these two dyes decreased (34.00% and 26.28% for safranin O and merbromin, respectively) because of the presence of other ions and molecules. A plausible mechanism for the removal of these pollutants using MOF-5 was proposed.

3.
Inorg Chem ; 62(19): 7304-7314, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37125995

RESUMO

The ternary phase with the composition Ni3InSb has been synthesized by high-temperature synthesis and structurally characterized by a combination of X-ray analysis, neutron diffraction analysis, and theoretical calculations. The structure of Ni3InSb crystallizes in the orthorhombic space group Pnma with lattice constants a = 7.111(3) Å, b = 5.193(3) Å, and c = 8.2113(2) Å. The crystal structure contains ∼20 atoms in its unit cell, which are distributed over four crystallographically independent positions (two Ni, one In, and one Sb). The crystal structure can be considered as a ternary substitutional variant of Ni3Sn2 (Pnma, no. 62), where a trivalent In and a pentavalent Sb orderly occupy two tetravalent Sn sites of Ni3Sn2. This site decoration pattern of two neighboring elements, In and Sb, is unique and confirmed by first principles total energy calculations. The crystal structure can be described by two building units: Ni2Sb (building unit of Ni2In) and NiIn (NiAs-type). They alternate in the crystal structure and form infinite ac-slabs (puckered), and the slabs are stacked along [010]. A triangular lattice formed by Ni atoms indicates the existence of a geometrically frustrated structure. The calculated density of states and crystal orbital Hamilton population enlighten the stability and bonding characteristics of the structure. The temperature-dependent neutron diffraction study down to 5 K reveals that the crystal structure remains in the same orthorhombic symmetry with a weak anomaly in the lattice parameters at ∼100 K. Detailed temperature- and magnetic field-dependent magnetic properties of the title phase Ni3InSb show spin-glass- or spin-disorder-like behaviors below ∼300 K with an unusual magnetic behavior below 100 K, where an enhancement of magnetization with a decrease of the coercive field has been found.

4.
Surg Endosc ; 37(12): 9414-9419, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37672111

RESUMO

BACKGROUND: Incisional hernia is a common complication following abdominal surgery. It causes change in function of core abdominal muscles leading to change in abdominal wall dynamics. This study aims to objectively measure and compare preoperative abdominal wall dynamics with surface electromyography (sEMG) in incisional hernia patients with healthy individuals. MATERIALS AND METHODS: In this prospective comparative study, two groups of participants as cases and controls were evaluated for their abdominal wall dynamics by using sEMG. Both cases and controls were evenly matched in terms of age and gender. Statistical analysis was done with STATA 14.1 and p value of < 0.05 was considered significant. RESULTS: Demographic profile was comparable between the two groups. Mean BMI of cases was higher than controls. The most common index procedure was lower segment cesarean section. The strength and power of all three abdominal wall muscles (rectus abdominis, external oblique, internal oblique) were significantly diminished among cases compared to controls. CONCLUSIONS: Abdominal wall dynamics can be objectively and correctly interpreted from sEMG of abdominal wall core muscles in patients with incisional hernia. This study shows that there is a decrease in abdominal wall strength and power in patients suffering from incisional hernia in comparison with healthy controls.


Assuntos
Parede Abdominal , Hérnia Ventral , Hérnia Incisional , Gravidez , Humanos , Feminino , Parede Abdominal/cirurgia , Hérnia Incisional/etiologia , Hérnia Incisional/cirurgia , Estudos Prospectivos , Cesárea , Músculos Abdominais/cirurgia , Hérnia Ventral/cirurgia
5.
Inorg Chem ; 60(8): 5488-5496, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33779152

RESUMO

A nonstoichiometric line phase, Rh3Cd5-δ (δ ∼ 0.56), is found in close vicinity to RhCd and structurally characterized by single-crystal X-ray diffraction and energy-dispersive X-ray spectroscopy. The compound crystallizes in the cubic space group Im3m (No. 229) with lattice constant a = 6.3859(9) Å and represents a 2 × 2 × 2 superstructure of RhCd, which accommodates a vacancy concentration of nearly 6% in its crystal structure. The first-principles electronic structure calculation on a hypothetical ordered configuration of Rh3Cd5-δ reveals that Rh-Cd heteroatomic interaction plays a major role in the stability of the compound. A combination of the total energy, formation energy, and crystal orbital Hamilton population calculations on hypothetical model configurations establishes that the compound upholds an optimum vacancy concentration in the Cd2a (Cd1) site for the stability of the phase.

6.
Indian J Crit Care Med ; 25(10): 1167-1172, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34916750

RESUMO

BACKGROUND: Focused assessment with sonography in trauma (FAST) is an important adjunct and an extension of the clinical examination in an emergency setting for the last three decades. e-FAST visualizes the lung bases and injuries related to the lungs in addition to the intra-abdominal and pericardial bleed. In trauma patients, time is precious. Noncontrast computed tomography (NCCT) chest is the gold standard for the evaluation of blunt trauma chest. However, it is cumbersome and time-consuming and leads to increased morbidity and mortality. Therefore, evaluation of trauma patients at the trauma bay with e-FAST which is available at all times will not only save time but also the lives of trauma patients. Our endeavor is to find whether e-FAST can be substituted for NCCT for assessing injuries accurately in a stable blunt trauma patient. PATIENT AND METHODS: Prospective observational study was conducted in a tertiary care trauma center during the period of November 2017 to 2019. Of the 197 patients presenting to the trauma surgeon in the trauma center, 110 were included in the study after satisfying the inclusion criteria. Eighty-seven patients being hemodynamically unstable were excluded from the study. RESULTS: There was no statistical significance in the comparative data between the groups and all with "p" values more than 0.05. This accepts the null hypothesis and establishes the fact that there is no difference between NCCT chest which is the gold standard for chest blunt trauma and e-FAST. CONCLUSION: We conclude that e-FAST is a better adjunct to the diagnosis and management of blunt trauma chest patients. HOW TO CITE THIS ARTICLE: Devadoss H, Sharma P, Nair VV, Rehsi SS, Roy N, Rao PP. Diagnostic Accuracy of e-FAST in Stable Blunt Trauma Chest: A Prospective Analysis of 110 Cases at a Tertiary Care Center. Indian J Crit Care Med 2021;25(10):1167-1172.

7.
Mol Divers ; 19(4): 991-1002, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26303382

RESUMO

The Apicomplexa parasite Plasmodium is a major cause of death in developing countries which are less equipped to bring new medicines to the market. Currently available drugs used for treatment of malaria are limited either by inadequate efficacy, toxicity and/or increased resistance. Availability of the genome sequence, microarray data and metabolic profile of Plasmodium parasite offers an opportunity for the identification of stage-specific genes important to the organism's lifecycle. In this study, microarray data were analysed for differential expression and overlapped onto metabolic pathways to identify differentially regulated pathways essential for transition to successive erythrocytic stages. The results obtained indicate that S-adenosylmethionine decarboxylase/ornithine decarboxylase, a bifunctional enzyme required for polyamine synthesis, is important for the Plasmodium cell growth in the absence of exogenous polyamines. S-adenosylmethionine decarboxylase/ornithine decarboxylase is a valuable target for designing therapeutically useful inhibitors. One such inhibitor, [Formula: see text]-difluoromethyl ornithine, is currently in use for the treatment of African sleeping sickness caused by Trypanosoma brucei. Structural studies of ornithine decarboxylase along with known inhibitors and their analogues were carried out to screen drug databases for more effective and less toxic compounds.


Assuntos
Antimaláricos/química , Plasmodium falciparum/enzimologia , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/química , Adenosilmetionina Descarboxilase/antagonistas & inibidores , Adenosilmetionina Descarboxilase/química , Antimaláricos/farmacologia , Desenho de Fármacos , Regulação da Expressão Gênica , Humanos , Redes e Vias Metabólicas/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Ornitina Descarboxilase/química , Filogenia , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Relação Estrutura-Atividade
8.
Plant Direct ; 8(6): e593, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38887667

RESUMO

Rice genetic diversity is regulated by multiple genes and is largely dependent on various environmental factors. Uncovering the genetic variations associated with the diversity in rice populations is the key to breed stable and high yielding rice varieties. We performed genome wide association studies (GWASs) on seven rice yielding traits (grain length, grain width, grain weight, panicle length, leaf length, leaf width, and leaf angle) based on a population of 183 rice landraces of Bangladesh. Our GWASs reveal various chromosomal regions and candidate genes that are associated with different traits in Bangladeshi rice varieties. Noteworthy was the recurrent implication of chromosome 10 in all three grain-shape-related traits (grain length, grain width, and grain weight), indicating its pivotal role in shaping rice grain morphology. Our study also underscores the involvement of transposon gene families across these three traits. For leaf related traits, chromosome 10 was found to harbor regions that are significantly associated with leaf length and leaf width. The results of these association studies support previous findings as well as provide additional insights into the genetic diversity of rice. This is the first known GWAS study on various yield-related traits in the varieties of Oryza sativa available in Bangladesh-the fourth largest rice-producing country. We believe this study will accelerate rice genetics research and breeding stable high-yielding rice in Bangladesh.

9.
Nat Genet ; 33(4): 522-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12640455

RESUMO

An organism's lifespan is modulated by environmental conditions. When nutrients are abundant, the metabolism of many organisms shifts to growth or reproduction at the expense of longer lifespan, whereas a scarcity of nutrients reverses this shift. These correlations suggest that organisms respond to environmental changes by altering their metabolism to promote either reproduction and growth or long life. The only previously reported signaling mechanism involved in this response is the nutrient-responsive insulin/insulin-like growth factor-1 receptor pathway. Here we report another pathway that controls the length of yeast lifespan. Commitment to cell growth activates the Slt2p MAP kinase pathway, which phosphorylates the transcriptional silencing protein Sir3p, resulting in a shorter lifespan. Elimination of the Sir3p phosphorylation site at Ser275 extended lifespan by 38%. Lifespan extension occurs by a mechanism that is independent of suppressing rDNA recombination. Thus, Slt2p is an enzymatic regulator of silencing function that couples commitment to cell growth and shorter lifespan.


Assuntos
Inativação Gênica , Proteínas Quinases Ativadas por Mitógeno , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Alelos , Western Blotting , Proteínas Fúngicas/metabolismo , Sistema de Sinalização das MAP Quinases , Modelos Biológicos , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Fases de Leitura Aberta , Fenótipo , Fosforilação , Testes de Precipitina , Estrutura Terciária de Proteína , Recombinação Genética , Fatores de Tempo
10.
Sci Rep ; 13(1): 12121, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495655

RESUMO

We investigate the nature of quantum criticality and topological phase transitions near the critical lines obtained for the extended Kitaev chain with next nearest neighbor hopping parameters and non-Hermitian chemical potential. We surprisingly find multiple gap-less points, the locations of which in the momentum space can change along the critical line unlike the Hermitian counterpart. The interesting simultaneous occurrences of vanishing and sign flipping behavior by real and imaginary components, respectively of the lowest excitation is observed near the topological phase transition. Introduction of non-Hermitian factor leads to an isolated critical point instead of a critical line and hence, reduced number of multi-critical points as compared to the Hermitian case. The critical exponents obtained for the multi-critical and critical points show a very distinct behavior from the Hermitian case.

11.
Osong Public Health Res Perspect ; 14(2): 119-128, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37183332

RESUMO

OBJECTIVES: Coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM) has emerged as a formidable infection in patients with COVID-19. The aggressive management of CAM affects quality of life (QOL); thus, this study was designed to assess the QOL in patients with CAM at a tertiary healthcare institution. METHODS: This cross-sectional study of 57 patients with CAM was conducted over 6 months using a semi-structured standard questionnaire (the abbreviated World Health Organization Quality of Life questionnaire [WHO-BREF]) and a self-rated improvement (SRI) scale ranging from 0 to 9. Cut-off values of ≤52 and <7 were considered to indicate poor QOL and poor improvement, respectively. The correlations of QOL and SRI scores were evaluated using Spearman rho values. RESULTS: In total, 27 patients (47.4%; 95% confidence interval [CI], 34.9%-60.1%) and 26 patients (45.6%; 95% CI, 33.4%-58.4%) had poor QOL and poor SRI scores, respectively. The overall median (interquartile range) QOL score was 52 (41-63). Headache (adjusted B, -12.3), localized facial puffiness (adjusted B , -16.4), facial discoloration (adjusted B, -23.4), loosening of teeth (adjusted B, -18.7), and facial palsy (adjusted B, -38.5) wer e significantly associated with the QOL score in patients with CAM. CONCLUSION: Approximately 1 in 2 patients with CAM had poor QOL and poor improvement. Various CAM symptoms were associated with QOL in these patients. Early recognition is the key to optimal treatment, improved outcomes, and improved QOL in patients with CAM.

12.
Proc Natl Acad Sci U S A ; 106(48): 20300-5, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19918083

RESUMO

In eukaryotic organisms, gene expression requires an additional level of coordination that links transcriptional and posttranslational processes. Messenger RNAs have traditionally been viewed as passive molecules in the pathway from transcription to translation. However, it is now clear that RNA-binding proteins (RBPs) play an important role in cellular homeostasis by controlling gene expression at the posttranscriptional level. Here, we show that RBPs, as a class of proteins, show distinct gene expression dynamics compared to other protein coding genes in the eukaryote Sacchoromyces cerevisiae. We find that RBPs generally exhibit high protein stability, translational efficiency, and protein abundance but their encoding transcripts tend to have a low half-life. We show that RBPs are also most often posttranslationally modified, indicating their potential for regulation at the protein level to control diverse cellular processes. Further analysis of the RBP-RNA interaction network showed that the number of distinct targets bound by an RBP (connectivity) is strongly correlated with its protein stability, translational efficiency, and abundance. We also note that RBPs show less noise in their expression in a population of cells, with highly connected RBPs showing significantly lower noise. Our results indicate that highly connected RBPs are likely to be tightly regulated at the protein level as significant changes in their expression may bring about large-scale changes in global expression levels by affecting their targets. These observations might explain the molecular basis behind the cause of a number of disorders associated with misexpression or mutation in RBPs. Future studies uncovering the posttranscriptional networks in higher eukaryotes can help our understanding of the link between different levels of regulation and their role in pathological conditions.


Assuntos
Regulação da Expressão Gênica/fisiologia , Redes Reguladoras de Genes/fisiologia , Modelos Biológicos , Processamento Pós-Transcricional do RNA/fisiologia , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae
13.
Artigo em Inglês | MEDLINE | ID: mdl-34518133

RESUMO

OBJECTIVE: To develop Automatic Oral Cancer Detection algorithm for identification and differentiation of premalignant lesions from buccal cavity images for early detection of oral cancer, which may reduce related fatalities in developing countries. STUDY DESIGN: The oral cavity images of normal, erythroplakia, and leukoplakia (20 images of each) were collected and processed using MATLAB image processing tools. First, maximum red value was used to differentiate between normal and abnormal. Second, mean red value was used for the selection of a processing path through YCbCr. Third, gray-level co-occurrence matrix (GLCM) based features were used to make final decisions. Images have been randomly divided and shuffled between training and test set to rigorously train the algorithm. RESULTS: With 100% efficiency, normal images were separated from abnormal images in the first step by applying R value distribution with a cutoff R value, 11,900. Further, images with a mean R value >200 and <200 were processed by segmentation of Y plane and Cr plane, respectively. For the final decision, abnormal images were analyzed through the GLCM using the entropy feature as one of the key indicators, which can apply to the differentiation decision with 89% efficiency. CONCLUSIONS: The developed algorithm can successfully differentiate premalignant lesions from normal. A graphic user interface was developed, which displays outcomes with reasonable accuracy.


Assuntos
Detecção Precoce de Câncer , Neoplasias Bucais , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Bucais/diagnóstico por imagem
14.
Rev Neurosci ; 22(3): 355-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21591907

RESUMO

Albumin is the most abundant plasma protein synthesised mainly in the liver. It is also a major component of extracellular fluids including cerebrospinal fluid, interstitial fluid and lymph. Albumin has several biochemical properties including regulation of colloid osmotic pressure of plasma, transportation of hormones, fatty acids, drugs and metabolites across plasma, regulation of microvascular permeability, antioxidant activity, anti-thrombotic activity and anti-inflammatory activity. This multifunctional protein has been implicated in many neurological diseases owing to its ability to regulate hemodynamic properties of the brain circulation as well as the direct neuroprotective actions on neuronal and glial cells. In this review, we summarise various neuroprotective actions of the albumin in the brain. In experimental ischemic stroke, exogenous human serum albumin administration has been found to be neuroprotective via reducing brain swelling, prevention of post-ischemic thrombosis, anti-oxidant activity, hemodilution and increasing the perfusion to the ischemic tissue. Also, human serum albumin administration is currently under clinical trials for treatment of cerebral ischemia. In the experimental models of Alzheimer's disease, albumin has been implicated in neuroprotection by inhibiting polymerisation and enhancing the clearance of amyloid ß. The direct neuroprotective actions on neuronal and glial cells are mediated via endogenously produced albumin or cellular uptake of blood derived albumin. These neuroprotective effects of albumin are partly attributed to anti-oxidant property and modulation of intracellular signalling of neuronal or glial cells. The recent finding of de novo synthesis of albumin in microglial cells directs us to explore newer roles of this endogenously produced multifunctional protein in normal as well as pathological conditions of the brain.


Assuntos
Albuminas/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Albuminas/metabolismo , Animais , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Modelos Biológicos
15.
Mol Divers ; 15(3): 733-50, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21327540

RESUMO

The docking studies and comparative molecular field analysis (CoMFA) were performed on highly active molecules of curcumine derivatives against 3' processing activity of HIV-1 integrase (IN) enzyme. The optimum CoMFA model was selected with statistically significant cross-validated r(2) value of 0.815 and non-cross validated r (2) value of 0.99. The common pharmacophore of highly active molecules was used for screening of HIV-1 IN inhibitors. The high contribution of polar interactions in pharmacophore mapping is well supported by docking and CoMFA results. The results of docking, CoMFA, and pharmacophore mapping give structural insights as well as important binding features of curcumine derivatives as HIV-1 IN inhibitors which can provide guidance for the rational design of novel HIV-1 IN inhibitors.


Assuntos
Curcumina/análogos & derivados , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/metabolismo , Integrase de HIV/metabolismo , Sítios de Ligação , Domínio Catalítico , Curcumina/química , Curcumina/farmacologia , Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Relação Quantitativa Estrutura-Atividade
16.
J Phys Condens Matter ; 33(33)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34062514

RESUMO

We investigate the nonequilibrium dynamics of entanglement entropy and out-of-time-order correlator (OTOC) of noninteracting fermions at half-filling starting from a product state to distinguish the delocalized, multifractal (in the limit of nearest neighbor hopping), localized and mixed phases hosted by the quasiperiodic Aubry-André-Harper (AAH) model in the presence of long-range hopping. For sufficiently long-range hopping strength a secondary logarithmic behavior in the entanglement entropy is found in the mixed phases whereas the primary behavior is a power-law the exponent of which is different in different phases. The saturation value of entanglement entropy in the delocalized, multifractal and mixed phases depends linearly on system size whereas in the localized phase (in the short-range regime) it is independent of system size. The early-time growth of OTOC shows very different power-law behaviors in the presence of nearest neighbor hopping and long-range hopping. The late time decay of OTOC leads to noticeably different power-law exponents in different phases. The spatial profile of OTOC and its system-size dependence also provide distinct features to distinguish phases. In the mixed phases the spatial profile of OTOC shows two different dependences on space for small and large distances respectively. Interestingly the spatial profile contains large fluctuations at the special locations related to the quasiperiodicity parameter in the presence of multifractal states.

17.
Asian Spine J ; 15(6): 874-880, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33355853

RESUMO

Respiratory failure and chronic ventilator dependence in tetraplegics following cervical injuries located high on the spine (C1-C3) constitute significant challenges in the rehabilitation of patients given the occurrence of repeated hospitalizations and an ever-increasing financial burden. A 30-year-old man presented with posttraumatic tetraplegia following an unstable injury at the C1-C2 level with cord compression; he was managed by posterior stabilization and decompression followed by ventilator dependence and no rehabilitation until 6 months postinjury. We implanted phrenic nerve stimulator electrodes bilaterally for indirect diaphragm pacing by an implantable pulse generator that allowed for weaning from mechanical ventilation and spontaneous ventilator-free breathing at 20 weeks post-implantation and which facilitated post-tetraplegia rehabilitation. At 36 months after implantation, the patient is ventilator-free without any procedure-related complications or respiratory infections. Diaphragm pacing with phrenic nerve stimulation may be a way forward for ventilator-dependent tetraplegics in developing countries to pursue effective rehabilitation and improved quality of life.

18.
Bioorg Med Chem Lett ; 20(13): 3972-6, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20488699

RESUMO

Histidinol dehydrogenase, the product of the HisD gene, mediates the final step in the histidine biosynthetic pathway. This enzyme has captured attention for drug discovery studies in past few years. Recently, our group cloned and expressed Geotrichum candidum histidinol dehydrogenase and successful screening of substrate analog inhibitors of histidinol dehydrogenase led to some antifungal compounds with IC(50) values in micromolar range. In this study, we have done docking analysis of these antifungal agents in G. candidum. Two new compounds were designed based on the docking results and these compounds turned out to be potent inhibitors of G. candidum histidinol dehydrogenase, showing IC(50) values as low as 3.17 microM.


Assuntos
Oxirredutases do Álcool/antagonistas & inibidores , Antifúngicos/farmacologia , Desenho de Fármacos , Geotrichum/enzimologia , Antifúngicos/síntese química , Antifúngicos/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
19.
Bioorg Med Chem Lett ; 20(3): 893-5, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20047831

RESUMO

A series of benzyl-[3-(benzylamino-methyl)-cyclohexylmethyl]-amine derivatives with different substitution pattern on the aromatic ring have been prepared and evaluated for their antibacterial activity against Gram-positive and Gram-negative bacterial strains. Most of the compounds exhibit potent activity against Pseudomonas aeruginosa and Staphylococcus epidermidis while compounds 6l and 6m showed antibacterial activity against all the four bacterial strains with MIC values ranging from 0.002 to 0.016 microg/mL and no hemolytic activity up to 512 microg/mL in mammalian erythrocytes was observed.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/fisiologia , Benzilaminas/síntese química , Benzilaminas/farmacologia , Cicloexanos/síntese química , Cicloexanos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana/métodos
20.
Mol Divers ; 14(1): 169-78, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19404761

RESUMO

The infectious disease burden imposed by trypanosomatidae family continues to create burden in countries that are least equipped to bring new medicines to the clinic. For sickness caused by this family of parasites (African trypanosomiasis, Chagas disease, and leishmaniasis) no vaccines are available, and currently available drugs suffer from insufficient efficacy, excessive toxicity, and steady loss of effectiveness due to resistance. Availability of the genome sequence of pathogens of this family offers a unique avenue for the identification of novel common drug targets for all three pathogens. Sirtuin family of nicotinamide adenine dinucleotide (NAD)-dependent deacetylases are remarkably conserved throughout evolution from archaebacteria to eukaryotes and plays an important role in trypanosomatidae biology and virulence. In order to gain insight for selective drug design, three-dimensional (3D) models of L. major, L. infantum, T. brucie, and T. cruzi sirtuin were constructed by homology modeling and compared with human sirtuin. The molecular electrostatic potentials and cavity depth analysis of these models suggest that the inhibitor binding catalytic domain has various minor structural differences in the active site of trypanosomal and human sirtuin, regardless of sequence similarity. These studies have implications for designing effective strategies to identify inhibitors that can be developed as novel broad-spectrum antitrypanosomal drugs.


Assuntos
Desenho de Fármacos , Sirtuína 2/química , Trypanosomatina/efeitos dos fármacos , Trypanosomatina/enzimologia , Sequência de Aminoácidos , Domínio Catalítico , Simulação por Computador , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Alinhamento de Sequência , Sirtuína 1/química , Sirtuína 1/genética , Sirtuína 2/antagonistas & inibidores , Sirtuína 2/genética , Especificidade da Espécie , Eletricidade Estática , Trypanosomatina/genética
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