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1.
Bioorg Med Chem Lett ; 36: 127810, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482292

RESUMO

Using Cu(I)-catalyzed cycloaddition of alkyne and azide reaction (CuAAC), a series of novel 1,2,3-triazole based imidazole derivatives (3a-e) have been synthesized. The synthesized molecules were characterized by spectroscopic techniques such as 1H NMR, 13C NMR, mass and elemental analysis. Antitubercular activity (anti-TB) against Mycobacterium tuberculosis H37Rv (Mtb) and cytotoxic activity against the mammalian Vero cell line was screened for the synthesized compounds. The compounds 3d and 3e displayed potent in vitro antitubercular activity and may serve as a lead for further optimization. Besides, the experimental findings were in line with the results of molecular docking. Also, the synthesized compounds have also been analyzed for ADME properties and the experimental finding facilitates the development of new and more potent anti-TB agents in this series in the future. Using fluorescence and UV-vis absorption spectroscopy, the binding interaction of compounds (3d and 3e) with human serum albumin (HSA) was investigated. The results showed that, as a result of HSA-compound complex, the fluorescence quenching of HSA by test compounds was a static quenching process. According to Forster's theory, energy transfer efficiency is calculated.


Assuntos
Antituberculosos/farmacologia , Imidazóis/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Albumina Sérica Humana/química , Triazóis/farmacologia , Animais , Antituberculosos/síntese química , Antituberculosos/química , Sítios de Ligação/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Humanos , Imidazóis/síntese química , Imidazóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química , Células Vero
2.
Genes Dev ; 27(5): 485-90, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23431031

RESUMO

Proper neurological function in humans requires precise control of levels of the epigenetic regulator methyl CpG-binding protein 2 (MeCP2). MeCP2 protein levels are low in fetal brains, where the predominant MECP2 transcripts have an unusually long 3' untranslated region (UTR). Here, we show that miR-483-5p, an intragenic microRNA of the imprinted IGF2, regulates MeCP2 levels through a human-specific binding site in the MECP2 long 3' UTR. We demonstrate the inverse correlation of miR-483-5p and MeCP2 levels in developing human brains and fibroblasts from Beckwith-Wiedemann syndrome patients. Importantly, expression of miR-483-5p rescues abnormal dendritic spine phenotype of neurons overexpressing human MeCP2. In addition, miR-483-5p modulates the levels of proteins of the MeCP2-interacting corepressor complexes, including HDAC4 and TBL1X. These data provide insight into the role of miR-483-5p in regulating the levels of MeCP2 and interacting proteins during human fetal development.


Assuntos
Encéfalo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , Sítios de Ligação , Encéfalo/embriologia , Encéfalo/fisiopatologia , Linhagem Celular , Feto/embriologia , Feto/metabolismo , Feto/fisiopatologia , Impressão Genômica , Humanos , Neurônios/patologia , Ligação Proteica
3.
Cereb Cortex ; 28(6): 1946-1958, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28449024

RESUMO

The neocortex of primates, including humans, contains more abundant and diverse inhibitory neurons compared with rodents, but the molecular foundations of these observations are unknown. Through integrative gene coexpression analysis, we determined a consensus transcriptional profile of GABAergic neurons in mid-gestation human neocortex. By comparing this profile to genes expressed in GABAergic neurons purified from neonatal mouse neocortex, we identified conserved and distinct aspects of gene expression in these cells between the species. We show here that the calcium-binding protein secretagogin (SCGN) is robustly expressed by neocortical GABAergic neurons derived from caudal ganglionic eminences (CGE) and lateral ganglionic eminences during human but not mouse brain development. Through electrophysiological and morphometric analyses, we examined the effects of SCGN expression on GABAergic neuron function and form. Forced expression of SCGN in CGE-derived mouse GABAergic neurons significantly increased total neurite length and arbor complexity following transplantation into mouse neocortex, revealing a molecular pathway that contributes to morphological differences in these cells between rodents and primates.


Assuntos
Neurônios GABAérgicos/metabolismo , Neocórtex/embriologia , Neurogênese/fisiologia , Secretagoginas/metabolismo , Animais , Humanos , Interneurônios/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neuritos/metabolismo , Transcriptoma
4.
Opt Express ; 25(3): 1618-1628, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29519016

RESUMO

We demonstrate fiber nonlinearity mitigation by using multiple optical phase conjugations (OPCs) in the WDM transmission systems of both 8 × 32-Gbaud PDM QPSK channels and 8 × 32-Gbaud PDM 16-QAM channels, showing improved performance over a single mid-span OPC and no OPC in terms of nonlinear threshold and a best achievable Q2 factor after transmission. In addition, after an even number of OPCs, the signal wavelength can be preserved after transmission. The performance of multiple OPCs for fiber nonlinearity mitigation was evaluated independently for WDM PDM QPSK signals and WDM PDM 16-QAM signals. The technique of multiple OPCs is proved to be transparent to modulation formats and effective for different transmission links. In the WDM PDM QPSK transmission system over 3600 km, by using multiple OPCs the nonlinear threshold (i.e. optimal signal launched power) was increased by ~5 dB compared to the case of no OPC and increased by ~2 dB compared to the case of mid-span OPC. In the WDM PDM 16-QAM transmission system over 912 km, by using the multiple OPCs the nonlinear threshold was increased by ~7 dB compared to the case of no OPC and increased by ~1 dB compared to the case of mid-span OPC. The improvements in the best achievable Q2 factors were more modest, ranging from 0.2 dB to 1.1 dB for the results presented.

5.
Matern Child Nutr ; 13 Suppl 22017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29032621

RESUMO

We analyse data from the 2012 Comprehensive Nutrition Survey in the State of Maharashtra, India, which surveyed 2,630 households. This is a unique dataset because in addition to nutritional status of mothers and children, it has information on diets of women and children and household food security. This rich dataset allows us to address three issues: whether household food security predicts higher diet diversity in children aged 6-23 months; whether household food security predicts lower risk of undernutrition; and whether the lower risk of undernutrition in children who live in food secure households is mediated by improved diet diversity for children. We find that children from moderately food insecure and severely food insecure households are more likely to have lower diet diversity scores. We find that the odds of a child being severely stunted, severely underweight, or severely wasted are higher in severely food insecure households. After controlling for children's diet diversity, and other child, maternal and household characteristics, we find that household food security is no longer statistically associated with stunting, wasting, or underweight. However, diet diversity of children is statistically significantly associated with whether a child is stunted or underweight. Our results although not causal provide evidence for understanding the extent to which household food insecurity affects children's diet diversity and how both these factors affect nutrition outcomes in children. Our analysis informs Government of Maharashtra's and India's National Nutrition Mission in their efforts for formulating appropriate policies and programmes to address child undernutrition.


Assuntos
Dieta/estatística & dados numéricos , Características da Família , Abastecimento de Alimentos/estatística & dados numéricos , Estado Nutricional , Estatura , Peso Corporal , Feminino , Transtornos do Crescimento/epidemiologia , Humanos , Índia/epidemiologia , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Masculino , Desnutrição/epidemiologia , Política Nutricional , Magreza/epidemiologia
6.
Opt Express ; 24(13): 14208-14, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27410578

RESUMO

Recently, there is increasing interest in utilizing Stokes vector receiver, which is a direct-detection technique with the capability to digitally track the polarization changes in fibers and decode information in multiple dimensions. Here, we report a monolithically integrated silicon photonic Stokes vector receiver, which consists of one polarization beam splitter, two polarization rotators, one 90-degree optical hybrid, and six germanium photodetectors. Paired with a silicon in-phase/quadrature modulator incorporating a power-tunable carrier in the orthogonal polarization, transmission at 128-Gb/s over 100-km fiber is achieved with direct detection.

7.
PLoS Genet ; 9(10): e1003858, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146628

RESUMO

During spermatogenesis, mRNA localization and translation are believed to be regulated in a stage-specific manner. We report here that the Protamine2 (Prm2) mRNA transits through chromatoid bodies of round spermatids and localizes to cytosol of elongating spermatids for translation. The transacting factor CBF-A, also termed Hnrnpab, contributes to temporal regulation of Prm2 translation. We found that CBF-A co-localizes with the Prm2 mRNA during spermatogenesis, directly binding to the A2RE/RTS element in the 3' UTR. Although both p37 and p42 CBF-A isoforms interacted with RTS, they associated with translationally repressed and de-repressed Prm2 mRNA, respectively. Only p42 was found to interact with the 5'cap complex, and to co-sediment with the Prm2 mRNA in polysomes. In CBF-A knockout mice, expression of protamine 2 (PRM2) was reduced and the Prm2 mRNA was prematurely translated in a subset of elongating spermatids. Moreover, a high percentage of sperm from the CBF-A knockout mouse showed abnormal DNA morphology. We suggest that CBF-A plays an important role in spermatogenesis by regulating stage-specific translation of testicular mRNAs.


Assuntos
Fator de Ligação a CCAAT/genética , Protaminas/metabolismo , Biossíntese de Proteínas , Proteínas de Ligação a RNA/genética , Espermatogênese/genética , Animais , Fator de Ligação a CCAAT/metabolismo , Citosol/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Polirribossomos , Protaminas/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Testículo/metabolismo
8.
Clin Endocrinol (Oxf) ; 82(3): 445-52, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25040494

RESUMO

OBJECTIVE: Distant metastases, although rare, account for maximum disease-related mortality in differentiated thyroid cancer (DTC). Lungs and bones are the most frequent sites of metastases. We sought to identify the prognostic factors in adult DTC patients presenting with pulmonary metastases at initial diagnosis. DESIGN: Retrospective cohort study. PATIENTS: From the medical records of 4370 patients, 200 patients aged more than 21 years who were identified to have pulmonary metastases at the time of diagnosis were included in the analysis. RESULTS: The sites of metastases were lungs alone in 133 (67%) patients, and additional sites in remaining 67 (33%) patients were as follows: bones in 59, liver in 4, brain in 2 and both bone and liver in two patients. During the mean follow-up of 61 months (range, 12-312 months), 76 patients achieved remission, 121 (60·5%) patients had biochemically and/or structurally persistent disease and three patients showed disease progression. Multivariate analysis revealed presence of macro-nodular (chest X-ray positive) pulmonary metastases and concomitant skeletal metastases as independent factors decreasing the likelihood of remission. Of the 76 patients with remission, 16 (21%) developed subsequent recurrence. Patient age >45 years and follicular histopathology were independently associated with greater hazards of developing recurrence. CONCLUSION: This study suggests that the patients with macro-nodular lung metastases and/or concomitant skeletal metastases have reduced odds of achieving remission. Moreover, significant number of patients recur even after complete remission with RAI treatment, hence strict surveillance is recommended especially in patients with age >45 years and/or with follicular histology of DTC.


Assuntos
Neoplasias Pulmonares/patologia , Neoplasias da Glândula Tireoide/patologia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
9.
Opt Express ; 23(5): 5723-37, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836802

RESUMO

The first realization of a wavelength-selective switch (WSS) with direct integration of few mode fibers (FMF) is fully described. The free-space optics FMF-WSS dynamically steers spectral information-bearing beams containing three spatial modes from an input port to one of nine output ports using a phase spatial light modulator. Sources of mode dependent losses (MDL) are identified, analytically analyzed and experimentally confirmed on account of different modal sensitivities to fiber coupling in imperfect imaging and at spectral channel edges due to mode clipping. These performance impacting effects can be reduced by adhering to provided design guidelines, which scale in support of higher spatial mode counts. The effect on data transmission of cascaded passband filtering and MDL build-up is experimentally investigated in detail.

10.
Opt Express ; 22(5): 5859-66, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663923

RESUMO

We demonstrate nonlinearity compensation of 37.5-GHz-spaced 128-Gb/s PDM-QPSK signals using dispersion-folded digital-backward-propagation and a spectrally-sliced receiver that simultaneously receives three WDM signals, showing mitigation of intra-channel and inter-channel nonlinear effects in a 2560-km dispersion-managed TWRS-fiber link. Intra-channel and adjacent inter-channel nonlinear compensation gains when WDM channels are fully populated in the C-band are estimated based on the GN-model.

11.
Opt Express ; 22(6): 6478-85, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24663996

RESUMO

We experimentally demonstrate the generation of 1.024-Tb/s Nyquist-WDM phase-conjugated vector twin waves (PCTWs), consisting of eight 128-Gb/s polarization-division-multiplexed QPSK signals and their idlers, by a broadband polarization-insensitive fiber optic parametric amplifier. This novel all-optical signal processing approach to generate WDM-PCTWs enables a 2-fold reduction in the needed optical transmitters as compared to the conventional approach where each idler is generated by a dedicated transmitter. Digital coherent superposition of the twin waves at the receiver enables more than doubled reach in a dispersion-managed transmission link. We further study the impact of polarization-mode dispersion on the performance gain brought by the phase-conjugated twin waves, showing a gain of ~3.8 dB in signal quality factors.

12.
J Phys Chem A ; 118(19): 3479-89, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24754644

RESUMO

A systematic study of six tetracyclones has been carried out using experimental and theoretical charge density analysis. A three pronged approach based on quantum theory of atoms in molecules (QTAIM), nucleus independent chemical shifts (NICS) criterion, and source function (SF) contributions has been performed to establish the degree of antiaromaticity of the central five-membered ring in all the derivatives. Electrostatic potentials mapped on the isodensity surface show that electron withdrawing substituents turn both C and O atoms of the carbonyl group more electropositive while retaining the direction of polarity.

13.
Zootaxa ; 3667: 1-89, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26079003

RESUMO

Based on a revision of available literature on the Indian Cladocera (Crustacea: Branchiopoda), we present an updated checklist, with taxonomical updates and comments for all taxa recorded since the start of research of this group in the country since 1860. We have listed a total of 137 valid taxa, of which most records belong to species groups that need revision worldwide. The situation in Indian Cladocera taxonomy is, at present, insufficient for realistic conclusions on biodiversity, ecology and biogeography. We list suggestions for an improvement of the current situation.


Assuntos
Distribuição Animal , Cladocera/classificação , Cladocera/fisiologia , Animais , Biodiversidade , Índia
14.
J Biomol Struct Dyn ; : 1-16, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477248

RESUMO

Two new quinazoline derivatives (2a and 2b) were successfully synthesized in this work using the condensation technique in excellent yields. Using spectroscopic techniques and elemental analyses, the compounds were completely characterized. Density functional theory (DFT) computations have been used to examine the title compound's reactive characteristics. Chemical reactivity was predicted using local reactive descriptors and molecule electrostatic potential. Additionally, Time dependent DFT (TD-DFT) simulations were used to examine the impact of solvents on the photophysical characteristics. The affinity of compounds 2a and 2b for human serum albumin (HSA) was further explored using several electronic spectroscopies. Through static mechanisms, both compounds reduce the intrinsic fluorescence of HSA. It is determined that the HSA-2b complex's binding constant is significantly greater than the HSA-2a complex. The fluorescence spectrum measurements proved that the HSA underwent structural changes after interaction with these compounds. It was demonstrated by site marker competitive displacement studies that compounds 2a and 2b preferred to bind to site I in HSA subdomain IIA. Additionally, synchronised fluorescence spectra were utilized to analyze how HSA's conformation changed after interacting with various substances. The molecular docking investigations of these compounds with the three critical HSA binding sites, comprising subdomains IIA, IIIA, and IB, further confirmed the experimental findings. The significant contact between the investigated compounds and HSA was supported by the docking simulations.Communicated by Ramaswamy H. Sarma.

15.
J Orthop Case Rep ; 13(9): 52-56, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37753119

RESUMO

Introduction: Paralabral cyst is benign fluid-filled lesion that occurs adjacent to glenoid labrum. Origin of the cyst can be traumatic or atraumatic. This cystic lesion can compress nearby axillary nerve or suprascapular nerve, resulting in shoulder pain and numbness. In this case report, we will discuss about anteroinferior paralabral cyst with axillary neuropathy in atraumatic condition. Case Report: A 35-year-old male was admitted in our institute with complaining of numbness in the mid-part of the lateral arm and pain in the posterior aspect in the left shoulder for 2 weeks. The patient has on-and-off pain in the left shoulder on lifting weight. He had no history of trauma. X-ray was normal. On examination, tenderness presents over the dorsal aspect of shoulder and reduced sensations over deltoid muscle (regimen badge sign). Deltoid atrophy was noted. Range of motion was normal. On examination, cervical spine was normal, and reduced sensation over the lateral aspect of arm and deltoid atrophy was present. Magnetic resonance imaging (MRI) shows large multiloculated paralabral cyst caudal to inferior glenoid rim. The diagnosis was compressive axillary neuropathy which was confirmed by nerve condition study. Conclusion: According to this case report, accurate early clinical examination and MRI evaluation are crucial in patients with atraumatic shoulder pain associated with neurological symptoms. On identification, cyst can be successfully decompressed by shoulder arthroscopy which can prevent axillary nerve damage, muscle denervation, and also recurrence of cyst can be avoided.

16.
Indian J Nucl Med ; 38(4): 392-393, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38390546

RESUMO

Tertiary hyperparathyroidism (THPT) is characterized by over secretion of parathyroid hormone caused by long-standing secondary hyperparathyroidism. THPT can affect the bones as well as cause extraskeletal calcifications. The bony lesions often mimic multiple skeletal metastases or multiple myeloma. We report a case of a 48-year-old man with chronic kidney disease on dialysis, who presented with chief complaints of low back ache and swelling over the left clavicle. In view of clinical suspicion of malignancy with bony metastases, he underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography and was subsequently found to have parathyroid adenomas, which were confirmed on 99mTc-methoxy-isobutyl-isonitrile scintigraphy.

17.
Opt Express ; 20(17): 19088-95, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23038549

RESUMO

Coherent superposition of light waves has long been used in various fields of science, and recent advances in digital coherent detection and space-division multiplexing have enabled the coherent superposition of information-carrying optical signals to achieve better communication fidelity on amplified-spontaneous-noise limited communication links. However, fiber nonlinearity introduces highly correlated distortions on identical signals and diminishes the benefit of coherent superposition in nonlinear transmission regime. Here we experimentally demonstrate that through coordinated scrambling of signal constellations at the transmitter, together with appropriate unscrambling at the receiver, the full benefit of coherent superposition is retained in the nonlinear transmission regime of a space-diversity fiber link based on an innovatively engineered multi-core fiber. This scrambled coherent superposition may provide the flexibility of trading communication capacity for performance in future optical fiber networks, and may open new possibilities in high-performance and secure optical communications.


Assuntos
Segurança Computacional/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Dinâmica não Linear
18.
Opt Express ; 20(26): B595-600, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23262907

RESUMO

We demonstrate the use of digital coherent superposition to improve the performance of space-division-multiplexed (SDM) 676-Gb/s OFDM-16QAM superchannels, achieving ~4 dB improvement in OSNR by using two SDM copies and 1075-km (14 x 76.8 km) transmission over a seven-core-fiber with an effective aggregate spectral efficiency of 23.7 b/s/Hz. We further show that the performance improvement from the coherent superposition is retained in the nonlinear transmission regime through coordinated scrambling of signal constellations at the transmitter and appropriate unscrambling at the receiver, by using a series of simple scrambling functions.

19.
Opt Express ; 20(2): 706-11, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22274415

RESUMO

We demonstrate 2688-km multi-span transmission using wavelength-division multiplexing (WDM) of ten 50-GHz spaced 128-Gb/s PDM-QPSK signals, space-division multiplexed (SDM) in a low-crosstalk 76.8-km seven-core fiber, achieving a record net aggregate per-fiber-spectral-efficiency-distance product of 40,320 km·b/s/Hz. The demonstration was enabled by a novel core-to-core signal rotation scheme implemented in a 7-fold, synchronized recirculating loop apparatus.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Fibras Ópticas , Telecomunicações/instrumentação , Eletrônica/instrumentação , Eletrônica/métodos , Desenho de Equipamento
20.
Opt Express ; 20(2): 896-904, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22274436

RESUMO

We propose a novel energy-efficient coherent-optical OFDM transmission scheme based on hybrid optical-electronic signal processing. We demonstrate transmission of a 0.26-Tb/s OFDM superchannel, consisting of 13 x 20-Gb/s polarization-multiplexed QPSK subcarrier channels, over 400-km standard single-mode fiber (SSMF) with BER less than 6.3x10(-4) using all-optical Fourier transform processing and electronic 7-tap blind digital equalization per subchannel. We further explore long-haul transmission over up to 960 km SSMF and show that the electronic signal processing is capable of compensating chromatic dispersion up to 16,000 ps/nm using only 15 taps per subchannel, even in the presence of strong inter-carrier interference.


Assuntos
Eletrônica/instrumentação , Eletrônica/métodos , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Análise de Fourier , Desenho de Equipamento , Modelos Teóricos
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