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1.
Phys Chem Chem Phys ; 22(3): 1027-1034, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31854408

RESUMO

Mass selected slow photoelectron spectra (SPES) of three boron-containing reactive species, BH2, BH, and BF were recorded by double imaging photoion-photoelectron coincidence spectroscopy (i2PEPICO) using synchrotron radiation. All species were generated in a flow reactor from the H-abstraction of B2H6 by F atoms created in a F2 microwave discharge. The spectrum of BH2+ exhibits a long bending mode progression with a 970 cm-1 spacing due to the large geometry change from bent to linear upon ionization. Its ionization energy was determined as 8.12 ± 0.02 eV. For BH, photoionisation from both X1Σ+ singlet and a3Π triplet state was observed, permitting the experimental determination of the singlet/triplet gap (ΔEST) from the observed IE's of 9.82 eV and 8.48 eV. In addition, a threshold photoelectron spectrum of BF was recorded, which leads to an IE of 11.11 eV and an improved value for νBF+ of 1690 cm-1. All spectra were simulated by calculating Franck-Condon factors from optimised structures based on quantum chemical calculations.

2.
Parasite Immunol ; 40(7): e12535, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29745990

RESUMO

Leishmania donovani, the causative parasite of Visceral Leishmaniasis (VL), deviously manipulates host monocytes/macrophages to ensure its survival. Although monocytes/macrophages from patients with VL have demonstrated an impaired oxidative burst and antigen presentation, an unanswered yet pertinent question remains as to whether they are deactivated or alternatively activated. The significantly raised plasma levels of IL-4/IL-13 and IL-10 in VL patients suggested a microenvironment conducive for alternative activation of monocytes/macrophages. Accordingly, the classical markers for IL-4-driven monocytes/macrophages [M(IL-4)] were studied namely intramonocytic CD206+ , circulating CCL22 and CCL17, and were unchanged. Furthermore, the mRNA expression of Kruppel-like factor 4 (KLF4), peroxisome proliferator-activated receptors (PPAR)-γ and arginase-I (ARG-I) in peripheral blood mononuclear cells was unaltered. However, markers for IL-10-driven monocytes/macrophages [M(IL-10)], namely soluble CD163, intramonocytic IL-10, and circulating CXCL13 were significantly increased. Monocytes/macrophages of patients with VL demonstrated an increased expression of markers for M(IL-10), along with the absence of markers for M(IL-4). Taken together, in human VL, manipulation of these IL-10 polarized monocytes-macrophages may pave the way for improved therapeutic outcomes.


Assuntos
Interleucina-10/análise , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Adulto , Idoso , Feminino , Humanos , Fator 4 Semelhante a Kruppel , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Explosão Respiratória
3.
J Vector Borne Dis ; 53(1): 23-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27004575

RESUMO

BACKGROUND & OBJECTIVES: Long-lasting insecticidal net (LLIN) is considered to be a highly effective intervention against malaria under National Vector Borne Disease Control Programme in India. A cross-sectional study was undertaken to assess the coverage and utilization of LLIN and the factors related thereto. METHODS: A survey of 1300 households was carried out in Ranibandh block of Bankura district in West Bengal, India, using lot quality assurance sampling (LQAS) method. Coverage/utilization of 80% was considered as minimum acceptable norm. The weighted sample size was calculated from each village of the block. The sociodemographic, economic information of the household along with the availability and use of LLIN was collected through interview and observation. RESULTS: In total, 7320 individuals including 840 children ≤ 5 yr were visited. Overall coverage of adequate LLIN was 65.4% (± 1.5%) and for children ≤ 5 yr, it was 60.5% (± 1.3%). Overall, 66.1% (± 1.4%) people of all ages and 63.7% (± 1.4%) children ≤ 5 yr slept under LLINs in the night before the survey. Out of 26 sub-centres, distribution of LLINs in 10 sub-centres was below the accepted norm, whereas utilization was sub-optimal in 19 sub-centres. In only 18.2% (± 0.5%) households, LLINs remained hanging during daytime. Poverty, caste, education, perception regarding malarial morbidity and preventive action of LLIN were associated significantly with the distribution of LLIN. Similarly, poverty (AOR = 2.14), threat perception regarding malarial morbidity (AOR = 1.51) and mortality (AOR = 2.52) were positively associated with the use of LLIN. Full utilization of bednets by under-fives of the households was higher in villages with sub-centres. INTERPRETATION & CONCLUSION: Around two-third population of the study area was effectively covered with LLIN. Higher proportion of socially marginalized people received LLIN. Threat perception regarding malaria was directly associated with both receipt and use of LLIN. Behaviour change communication on utilization along with adequate access to LLIN needs to be strengthened.


Assuntos
Transmissão de Doença Infecciosa/prevenção & controle , Mosquiteiros Tratados com Inseticida/provisão & distribuição , Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Malária/prevenção & controle , Controle de Mosquitos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Doenças Endêmicas , Características da Família , Feminino , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Malária/epidemiologia , Masculino , Pessoa de Meia-Idade , Gravidez , Inquéritos e Questionários , Adulto Jovem
4.
J Phys Chem A ; 118(33): 6361-6, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24521509

RESUMO

We report here on the two lowest, rigorous-accurate diabatic potential energy surfaces (PES), for the F + H2 system, as calculated by including the two dominant topological effects of this system at the low energy region, namely, the Jahn-Teller effect and the Renner-Teller effect. Both effects were treated in the most rigorous way as demanded by the Born-Oppenheimer approach. No approximations were made, and in those cases where convergence was required, it was satisfied. In other words, convergence was attained in all situations. The numerical part that includes the calculation of the two lowest ab initio adiabatic PESs and the corresponding nonadiabatic coupling terms (NACTs) was carried out using the MOLPRO program. The required diabatic potentials are calculated by employing these ab initio adiabatic PESs and the corresponding adiabatic-to-diabatic angles as obtained employing the above-mentioned ab initio NACTs. The relevance of these Renner-Teller/Jahn-Teller diabatic potentials is studied by comparing the dressed-lowest ab initio adiabatic PES and the one formed by diagonalizing the dressed-diabatic 2 × 2 potential matrix. The dressed-potentials are calculated employing the vib-rotational manifold derived for each of the three surfaces, namely, the lowest adiabatic potential and the two diabatic ones. This kind of study was recently recommended by Lipoff and Herschbach ( Mol. Phys. 2010 , 108 , 1133 ) as a "blessed-practice" for the relevance of any PES. In the present case significant differences were revealed between the two types of dressed-adiabatic PESs, eventually, indicating that the lowest, ab initio PES (due to the Born-Oppenheimer approximation) is not adequate for low energy processes.

5.
ScientificWorldJournal ; 2014: 589543, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24672341

RESUMO

Numerical study on AHWR fuel bundle has been carried out to assess influence of circumferential and cross flow rewetting on the conduction heat transfer. The AHWR fuel bundle quenching under accident condition is designed primarily with radial jets at several axial locations. A 3D (r, θ, z) transient conduction fuel pin model has been developed to carry out the study with a finite difference method (FDM) technique with alternating direction implicit (ADI) scheme. The single pin has been considered to study effect of circumferential conduction and multipins have been considered to study the influence of cross flow. Both analyses are carried out with the same fluid temperature and heat transfer coefficients as boundary conditions. It has been found from the analyses that, for radial jet, the circumferential conduction is significant and due to influence of overall cross flow the reductions in fuel temperature in the same quench plane in different rings are different with same initial surface temperature. Influence of cross flow on rewetting is found to be very significant. Outer fuel pins rewetting time is higher than inner.


Assuntos
Modelos Teóricos , Molhabilidade
6.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38683055

RESUMO

In the pursuit of precise diagnostics for measuring negative ion density in a helicon plasma source (HPS), a new approach utilizing a radio frequency (RF) broadband transformer-based Langmuir probe is developed specifically for laser photo-detachment (LPD) analysis. This inductively coupled LPD technique is useful for high power RF systems in which capacitive RF noise is in the same scale as the pulsed photo-detachment signal. The signal acquired by this transformer-based probe is compared against the conventional Langmuir probe-based LPD technique, revealing a remarkable enhancement in signal fidelity through an improved signal-to-noise ratio (SNR) achieved by the RF broadband transformer methodology. In addition, the localized hydrogen negative ion density measurements obtained through this probe are harmoniously aligned with the line-averaged negative ion density derived from the cavity ringdown spectroscopy (CRDS) technique. These concurrence measurements highlight the RF broadband transformer-based approach's accuracy in capturing localized negative ion density during helicon mode operation in an HPS setup. Furthermore, the correlation of negative ion density values with RF input exhibits a consistent trend in tandem with background plasma density. Notably, both CRDS and LPD measurements ascertain negative ion densities ranging from ∼5 to 6×1016 m-3 under an RF power of 500-700 W and a pressure of 8 × 10-3 mbar, all under the influence of a 55 G axial magnetic field. These specific parameters represent the optimal operational configuration for effective negative ion production with the present experimental HPS setup. Due to its better SNR, the RF broadband transformer-based Langmuir probe emerges as a useful tool for LPD diagnostics, particularly in the presence of pervasive RF noise.

7.
Pulmonology ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38402124

RESUMO

BACKGROUND: Asbestos is still the leading cause of occupational cancer mortality worldwide. Asbestos-related lung cancer (LC) and malignant pleural mesothelioma (MPM) prognosis is still poor especially at advanced stage, so early diagnosis biomarkers are needed. MicroRNAs (miRNAs) have been proposed as potential early diagnostic biomarkers of asbestos-related LC and MPM. AIM: To evaluate the role of miRNAs as diagnostic and prognostic biomarkers of asbestos-related LC and MPM by performing a literature systematic review and meta-analysis. METHODS: MEDLINE, EMBASE via Ovid, PUBMED and Cochrane library databases were systematically searched up to April 2023 to identify relevant articles. A grey literature search was also conducted using the Google Scholar platform. MeSH and free text terms for 'asbestos', 'occupational exposure', 'lung cancer', 'mesothelioma' and 'miRNAs' were used to search the literature. Our systematic review protocol was registered in the PROSPERO database. Study quality was assessed via the Newcastle-Ottawa Scale. RESULTS: From the search, 331 articles were retrieved, and, after applying our selection criteria, and exclusion of one study for poor quality, 27 studies were included in the review. Most of the studies were hospital-based case-control, conducted in Europe, and evaluated MPM among men only. MiRNAs expression was measured mainly in plasma or serum. MiR-126, miR-132-3p, and miR-103a-3p were the most promising diagnostic biomarkers for MPM, and we estimated a pooled area under the curve (AUC) of 85 %, 73 %, and 50 %, respectively. In relation to MPM prognosis, miR-197­3p resulted associated with increased survival time. MiR-126, alone and combined with miR-222, was confirmed associated also to LC diagnosis, together with miR-1254 and miR-574-5p; no miRNA was found associated to LC prognosis. CONCLUSION: Based on our systematic literature review there is suggestive evidence that the expression of specific miRNAs in the blood serum or plasma are associated with asbestos-related LC and MPM diagnosis and prognosis. Further large longitudinal studies are urgently needed to validate these findings and elucidate the underlying mechanisms given the potential important implications for patients' survival.

8.
J Phys Chem A ; 117(36): 8497-505, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-23323799

RESUMO

We follow a suggestion by Lipoff and Herschbach (Mol. Phys. 2010, 108, 1133) and compare dressed potentials to get insight regarding the low-energy dynamics (e.g., cold reaction) taking place in molecular systems. In this particular case we are interested in studying the effect of topological effects on the interacting atoms. For this purpose we consider dressed adiabatic and adiabatic-via-dressed diabatic potentials in the entrance channel of reactive systems. In a recent study of this kind for the F + H2 system (J. Chem. Phys. 2012, 136, 054104), we revealed that a single Jahn-Teller conical intersection is expected to have only a mild effect on the dynamics. This fact implies that the Born-Oppenheimer approximation is expected to be valid for this system at least for low enough energies. In the present article this study is extended to include also the Renner-Teller effect as produced by the two lower degenerate Π states. As a result we consider three electronic states which enforce the use of the adiabatic-to-diabatic transformation (ADT) matrix A. The results indicate that the topological effects as produced by the extended Renner/Teller-Jahn/Teller system are strong to the level that, most likely, abolishes the Born-Oppenheimer approximation for this system, all this in contrast to our previous findings (see above publication).

9.
J Chem Phys ; 138(2): 024113, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23320674

RESUMO

The present study concentrates on a situation where a Renner-Teller (RT) system is entangled with Jahn-Teller (JT) conical intersections. Studies of this type were performed in the past for contours that surround the RT seam located along the collinear axis [see, for instance, G. J. Halász, Á. Vibók, R. Baer, and M. Baer, J. Chem. Phys. 125, 094102 (2006)]. The present study is characterized by planar contours that intersect the collinear axis, thus, forming a unique type of RT-non-adiabatic coupling terms (NACT) expressed in terms of Dirac-δ functions. Consequently, to calculate the required adiabatic-to-diabatic (mixing) angles, a new approach is developed. During this study we revealed the existence of a novel molecular parameter, η, which yields the coupling between the RT and the JT NACTs. This parameter was found to be a pure number η = 22/π (and therefore independent of any particular molecular system) and is designated as Renner-Jahn coupling parameter. The present study also reveals an unexpected result of the following kind: It is well known that each (complete) group of states, responsible for either the JT-effect or the RT-effect, forms a Hilbert space of its own. However, the entanglement between these two effects forms a third effect, namely, the RT/JT effect and the states that take part in it form a different Hilbert space.


Assuntos
Teoria Quântica , Algoritmos , Modelos Químicos , Termodinâmica
10.
Environ Geochem Health ; 35(1): 119-32, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22618763

RESUMO

Arsenic contamination in groundwater is becoming more and more a worldwide problem. Nearing 50 million of people are at health risk from arsenic contamination at Ganga-Meghna-Bramhaputra basin. The experimental results of the five blocks under Malda district of West Bengal, India, showed that the arsenic concentration in groundwater (0.41-1.01 mg/l) was higher than the permissible limit for drinking water (0.01 mg/l) (WHO) and FAO (Food and Agriculture Organization) permissible limit for irrigation water (0.10 mg/l). The soil arsenic level (13.12 mg/kg) crossed the global average (10.0 mg/kg), but within the maximum acceptable limit for agricultural soil (20.0 mg/kg) recommended by the European Union. The total arsenic concentration on food crops varied from 0.000 to 1.464 mg/kg of dry weight. The highest mean arsenic concentration was found in potato (0.456 mg/kg), followed by rice grain (0.429 mg/kg). The total mean arsenic content (milligrams per kg dry weight) in cereals ranged from 0.121 to 0.429 mg/kg, in pulses and oilseeds ranged from 0.076 to 0.168 mg/kg, in tuber crops ranged from 0.243 to 0.456 mg/kg, in spices ranged from 0.031 to 0.175 mg/kg, in fruits ranged from 0.021 to 0.145 mg/kg and in vegetables ranged from 0.032 to 0.411 mg/kg, respectively. Hence, arsenic accumulation in cereals, pulses, oilseed, vegetables, spices, cole crop and fruits crop might not be safe in future without any sustainable mitigation strategies to avert the potential arsenic toxicity on the human health in the contaminated areas.


Assuntos
Arsênio/análise , Água Subterrânea/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola/normas , Agricultura , Arsênio/química , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Contaminação de Alimentos , Água Subterrânea/química , Humanos , Índia , Poluentes do Solo/química , Poluentes Químicos da Água/química , Abastecimento de Água/normas
11.
Nucleic Acids Res ; 38(3): 878-92, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19934260

RESUMO

Earlier we have shown that exogenous expression of HIPPI, a molecular partner of Huntingtin interacting protein HIP-1, induces apoptosis and increases expression of caspases-1, -8 and -10 in HeLa and Neuro2A cells. The C-terminal pseudo death effector domain of HIPPI (pDED-HIPPI) specifically interacts with the putative promoter sequences of these genes. In the present manuscript, we predict from structural modeling of pDED-HIPPI that R393 of HIPPI is important for such interaction. R393E mutation in pDED-HIPPI decreases the interaction with the putative promoter of caspase-1 in cells. Expression of caspase-1 is decreased in cells expressing mutant pDED-HIPPI in comparison to that observed in cells expressing wild type pDED-HIPPI. Using HIP-1 knocked down cells as well as over expressing HIP-1 with mutation at its nuclear localization signal and other deletion mutations, we demonstrate that translocation of HIPPI to the nucleus is mediated by HIP-1 for the increased expression of caspase-1. HIPPI-HIP-1 heterodimer is detected in cytoplasm as well as in the nucleus and is associated with transcription complex in cells. Taking together, we are able to show the importance of R393 of HIPPI and the role of HIPPI-HIP-1 heterodimer in the transcription regulation of caspase-1.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Caspase 1/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Transcrição Gênica , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Apoptose , Caspase 1/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , DNA/química , Proteínas de Ligação a DNA/química , Dimerização , Células HeLa , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Regiões Promotoras Genéticas
12.
Nat Med ; 7(5): 569-74, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11329058

RESUMO

Angiogenesis has an essential role in many important pathological and physiological settings. It has been shown that vascular permeability factor/vascular endothelial growth factor (VPF/VEGF), a potent cytokine expressed by most malignant tumors, has critical roles in vasculogenesis and both physiological and pathological angiogenesis. We report here that at non-toxic levels, the neurotransmitter dopamine strongly and selectively inhibited the vascular permeabilizing and angiogenic activities of VPF/VEGF. Dopamine acted through D2 dopamine receptors to induce endocytosis of VEGF receptor 2, which is critical for promoting angiogenesis, thereby preventing VPF/VEGF binding, receptor phosphorylation and subsequent signaling steps. The action of dopamine was specific for VPF/VEGF and did not affect other mediators of microvascular permeability or endothelial-cell proliferation or migration. These results reveal a new link between the nervous system and angiogenesis and indicate that dopamine and other D2 receptors, already in clinical use for other purposes, might have value in anti-angiogenesis therapy.


Assuntos
Dopamina/farmacologia , Fatores de Crescimento Endotelial/fisiologia , Linfocinas/fisiologia , Neovascularização Patológica , Isoformas de Proteínas/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Linfocinas/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Fosforilação , Ligação Proteica , Isoformas de Proteínas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
14.
Andrologia ; 42(4): 242-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20629647

RESUMO

This study was conducted after an initial epidemiological survey of patients in and around Calcutta, India, concerning their lifestyle history, degree of risk exposure and semen analysis based on conventional WHO criteria. It was found that a large group of exposed patients were showing normozoospermic semen parameters in conventional semen analysis. Hence, a selected group of subjects, designated as normozoospermic in routine analysis, but under risk factor exposure, were selected for a repeat computer aided semen analysis (CASA) and were compared with a control group. The parameters considered among CASA results were: curvilinear velocity (VCL), straight-line velocity, average path velocity (VAP), straightness index (STR), lateral head displacement (ALH) and beat cross frequency. The results depict a significant decline in the mean values of VCL (P = 0.029) and STR (P = 0.007) in the tobacco-exposed group when compared with the unexposed group. On the other hand, there was a significant decline in the mean values of VCL (P = 0.014) and ALH (P = 0.040) in the heavy metal-exposed group when compared with the unexposed group. The other parameters did not show significant change in either group. Semen samples that had been designated normozoospermic in conventional analysis were seen to be influenced by risk factors at the level of sperm motion kinetics.


Assuntos
Exposição Ambiental/efeitos adversos , Processamento de Imagem Assistida por Computador/métodos , Metais Pesados/toxicidade , Análise do Sêmen/métodos , Sêmen/efeitos dos fármacos , Fumar/efeitos adversos , Motilidade dos Espermatozoides , Humanos , Índia , Estilo de Vida , Masculino , Fatores de Risco , Espermatozoides/patologia
15.
Environ Sci Pollut Res Int ; 27(30): 37745-37759, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32613499

RESUMO

This study investigates the kinked exponential growth, degree of association, and causation between economic growth, energy consumption, population, trade openness, and carbon dioxide (CO2) emissions in 25 upper middle-income group countries spanning data from 1985 to 2014. The study employed first-generation and second-generation unit root tests; prior to that, the cross-sectional dependence test is also applied and panel cointegration techniques, panel FMOLS and DOLS, and panel causality techniques are employed to test the degree of association and causation among the variables. The study reveals a long-run cointegration among the variables. Results of FMOLS declare that there are negative associations between economic growth and CO2 emissions, trade openness, and carbon dioxide emissions respectively, whereas it was found that there are positive relations between energy consumption and CO2 emissions, population, and CO2 emissions. While analyzing the association through DOLS, we find that all the selected determinants of carbon dioxide emissions are directly proportional to CO2 emissions in these countries. The panel Granger causality test indicates that there is bi-directional causality between population and economic growth and between trade openness and economic growth. Finally, the study ends with some policy suggestions and new avenues for future research.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Estudos Transversais , Renda , Políticas
16.
Science ; 243(4896): 1337-40, 1989 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-17808265

RESUMO

The Archean Kolar Schist Belt, south India, is a suture zone where two gneiss terranes and at least two amphibolite terranes with distinct histories were accrted. Amphibolites from the eastern and western sides of the schist belt have distinct incompatible element and isotopic characteristics sugesting that their volcanic protoliths were derived from dint mantle sources. The amphibolite and gneiss terranes were juxtaposed by horizontal compression and shearing between 2530 and 2420 million years ago (Ma) along a zone marked by the Kolar Schist Belt. This history of accretion of discrete crustal terranes resembles those of Phanerozoic convergent margins and thus suggests that plate tectonics operated on Earth by 2500 Ma.

17.
Andrologia ; 41(4): 207-15, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19601931

RESUMO

Reports indicate an increase in the incidence of DNA fragmentation in male factor infertility and its role in the outcome of assisted reproductive techniques (ART). However, reports are conflicting between the relationships of sperm DNA integrity with conventional semen parameters. We examined the relationship between conventional sperm parameters and DNA integrity using acridine orange (AO) test. The study included 373 patients and 28 fertile volunteers. DNA normality was compared with semen parameters between the patient and donor populations. Significant correlations were noted between DNA normality and sperm concentration (r = 0.18, P = 0.000), motility (r = 0.21, P = 0.0001), rapid motility (0.19, P = 0.000), normal morphology by World Health Organization (r = 0.15, P = 0.019) and head defects (r = -0.15, P = 0.023). A significant difference was noted in AO levels between donors and patients with asthenozoospermia (P = 0.002) and oligoasthenozoospermia (P = 0.001). A significant difference in DNA integrity was noted in samples having <30% and >30% normal morphology. A wide range of % DNA normality was observed in the patient group. Sperm assessment for DNA status using AO is reliable and shows good correlation with sperm count, motility and morphology. Assessment of sperm DNA status with AO staining may be helpful prior to ART.


Assuntos
Fragmentação do DNA , DNA/genética , Análise do Sêmen , Espermatozoides/fisiologia , Laranja de Acridina , Humanos , Infertilidade Masculina/genética , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Doadores de Tecidos
18.
Indian J Public Health ; 53(4): 256-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20469770

RESUMO

A cross-sectional study using lot quality technique was undertaken among a sample of 198 women in 18 sub-centers (lots) of Bankura-I Community Development Block who had delivered in last 12 months preceding the survey to find out the sub-center(s) with 'acceptable' coverage (> or = 50%) and overall coverage of 'appropriate' antenatal care of the block. Registration before 12 weeks, three antenatal check-ups with checking of BP, weight, edema and abdominal examination, distribution of 100 IFA tablets and adequate tetanus prophylaxis were taken collectively as a measure of'appropriate' antenatal care. Out of 18 sub-centers, only one had 'acceptable' coverage of appropriate antenatal care. The overall coverage of 'appropriate' antenatal care was 29.1% in the study Block.


Assuntos
Amostragem para Garantia da Qualidade de Lotes/estatística & dados numéricos , Cuidado Pré-Natal/normas , Feminino , Humanos , Índia , Gravidez , Cuidado Pré-Natal/estatística & dados numéricos
19.
Rev Sci Instrum ; 90(8): 083103, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472659

RESUMO

In the present work, a permanent magnet-based helicon plasma source (HELEN) is characterized as a negative ion source. A noninvasive diagnostic technique based on cavity ring down spectroscopy (CRDS) is developed to measure the line-integrated negative hydrogen ion (H-) density in HELEN. This paper discusses the experimental results in which negative hydrogen ion density is measured for different magnetic field, pressure, and RF (13.56 MHz) power configurations. It is observed that in high power range (800-850 W), the source is operating in helicon wave heating mode with a background plasma density of ∼1018 m-3 and electron temperature of ∼2 eV. Negative hydrogen ion density is measured by CRDS method and also by optical emission spectroscopic technique. The measured negative ion density is in the range of ∼1016 m-3 under volume mode operational condition even without any use of standard magnetic filter or cesium seeding in the downstream region. The influence of pressure variation (pressure range from 4 × 10-3 mbar to 4 × 10-2 mbar) on negative ion density production is not significant, except for a particular axial magnetic field configuration (55 G) and at 8 × 10-3 mbar pressure, where ∼34% hike is observed.

20.
Int J Pharm ; 356(1-2): 193-9, 2008 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-18337028

RESUMO

Paracetamol-alginate (Keltone HVCR) (1:1) granules were prepared by a wet granulation process followed by crosslinking of dried granules in calcium chloride solution. The effect of shear (planetary (low), Brabender (high)), binder quantity (1:2, 1:1 water:powder) and drug particle size (PS 98, 275 microm) were studied using a factorial design. Supporting studies were carried out varying binder quantity and alginate grade (viscosity). In the pre-treated granules, drug entrapment was mainly influenced by drug PS, where the smaller particles showed better embedding. After crosslinking, drug particle size continued to be the most important factor influencing drug recovery. All factors influenced early stage release where high shear, high binder, small drug PS granules showed least release and the low shear, low binder and large drug PS granules showed greatest release. Some significant two-factor interactions were found. Granule consolidation (shown by SEM) and particle embedding increased with binder quantity and reduced as the alginate viscosity was increased. Crosslinking, as shown by Na and Ca contents was >90%. The impact of granule consolidation on drug entrapment and recovery was relatively small (<10%) when compared to its effect on early stage drug release (>60%) which may be important if these granule systems are to be used for taste improvement.


Assuntos
Acetaminofen/química , Alginatos/química , Excipientes/química , Cloreto de Cálcio/química , Química Farmacêutica , Reagentes de Ligações Cruzadas/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Pós/química , Viscosidade
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