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1.
Bull Environ Contam Toxicol ; 111(3): 44, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37715801

RESUMO

Moyna of Purba Medinipur district is widely known as an aquaculture hub of West Bengal, India. Though very good production is achievable from this fish culture system, management practices are inappropriate, which could create the sustainability problem of this culture system. The present study was thus undertaken for the estimation of plankton population, water quality, carbon footprint and carbon sequestration of this intensive aquaculture practices. Information on spawn to fry, fry to fingerlings and grow-out culture were collected through the structured questionnaire from the fish farmers. The plankton density, primary productivity, carbon footprint and carbon sequestration were analyzed using standard procedures. The phytoplankton, zooplankton and primary productivity were maximum at the stocking period and minimum during the middle of culture period. The lowest feed conversion ratio (FCR) was noticed with the minimum amount of feed applied in the pond. The CO2-e emission ranged from 0.56 to 4.89 kg CO2-e/kg fish (av. 2.13) for the production levels of 5.0 to 10.7 t/ha/yr. The pond water developed salinity and ammonium-N increased from 0.01 to 0.50 mg/l. The ponds with high feed loading (28 to 32 t/ha/yr) had the highest average sediment accumulation rate (11.0 ± 3.0 cm/yr) and carbon sequestration (704 ± 30 g C/m2/yr).


Assuntos
Pegada de Carbono , Sequestro de Carbono , Animais , Dióxido de Carbono , Aquicultura , Índia , Plâncton
3.
J Mater Chem B ; 4(19): 3292-3304, 2016 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263264

RESUMO

In this study, mesoporous silica nanoparticles (MSPs) of different size and shape were developed, and their surface coatings were utilized to study their differential effects in enhancing antibacterial activity. In brief, MSPs with three different aspect ratios (1, 2 and 4) were prepared, doped with silver ions and finally coated with the polymer chitosan. Both Gram-positive and Gram-negative bacteria were treated with the MSPs. Results indicate that silver ion doped and chitosan coated MSPs with the aspect ratio of 4 (Cht/MSP4:Ag+) have the highest antimicrobial activity among the prepared series. Further studies revealed that Cht/MSP4:Ag+ was most effective against Escherichia coli (E.coli) and least effective against Vibrio cholerae (V. cholerae). To investigate the detailed inhibition mechanism of the MSPs, the interaction of the nanoparticles with E.coli membranes and its intracellular DNA was assessed using various spectroscopic and imaging-based techniques. Furthermore, to increase the efficiency of the MSPs, a combinatorial antibacterial strategy was also explored, where nanoparticles, in combination with kanamycin (antibiotic), were used against Vibrio Cholerae (V. cholerae). Toxicity screening of these on MSPs was conducted on Caco-2 cells, and the results show that the dose used for antibacterial screening is below the limit of the toxicity threshold. Our findings show that both shape and surface engineering contribute positively towards killing bacteria, and the newly developed silver ion-doped and chitosan-coated MSPs have good potential as antimicrobial nanomaterials.

4.
J Nanosci Nanotechnol ; 15(12): 9636-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26682390

RESUMO

The paper presents the results of our experimental investigation pertaining to tailoring of energy bandgap and other associated characteristics of undoped and Al doped ZnO (AZO) thin film by varying the atomic concentration of Al in ZnO. Thin films of ZnO and ZnO doped with Al (1, 3, and 5 atomic percent (at.%)) were deposited on silicon substrate for structural characterization and on glass substrate for optical characterization. The dependence of structural and optical properties of Al doped ZnO on the atomic concentration of Al added to ZnO has been reported. On the basis of the experimental results an empirical formula has been proposed to calculate the energy bandgap of AZO theoretically in the range of 1 to 5 at.% of Al. The study revealed that AZO films are composed of smaller and larger number of grains as compared to pure ZnO counterpart and density of the grains was found to increase as the Al concentration increased (from 1 to 5 at.%). The transmittance in the visible region was greater than 90% and found to increase with increasing Al concentration up to 5 at.%. The optical bandgap was found to increase initially with increase in atomic concentration of Al concentration up to 3 at.% and decrease thereafter with increasing concentration of Al.

6.
Cell Death Discov ; 1: 15016, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551450

RESUMO

For rapid tumor growth, cancer cells often reprogram the cellular metabolic processes to obtain enhanced anabolic precursors and energy. The molecular changes of such metabolic rewiring are far from established. Here we explored the role of mTOR (mechanistic target of rapamycin), which serves as a key regulator of cell growth, proliferation and survival, in the metabolic reprograming of cancer cells. When we inhibited mTOR in human hepatocellular carcinoma (HCC) and renal cell carcinoma (RCC) cells, using pharmacologic inhibitors or by RNA interference, we noticed shuttle of the glycolytic flux to gluconeogenesis pathway along with reduction in cellular proliferation and survival. Augmentation of gluconeogenesis was mechanistically linked to upregulation of the key gluconeogenic enzymes PCK1 and G6PC expressions, enhanced lactate dehydrogenase activity and glucose-derived lipogenesis without causing any attenuation in mitochondrial function. Interestingly, concomitant knocking down of PCK1 and not G6PC along with mTOR pathway could overcome the inhibition of cancer cell proliferation and survival. These observations were validated by identifying distinctive diminution of PCK1 and G6PC expressions in human HCC and RCC transcriptome data. Significant correlation between mTOR-dependent upregulation of PCK1 and cell death in different cancer cell lines further emphasizes the physiological relevance of this pathway. We reveal for the first time that inhibition of mTORC2 and consequent redistribution of glycolytic flux can have a prosurvival role in HCC and RCC cancer cells only in the presence of downregulation of gluconeogenesis pathway genes, thus identifying novel pivots of cancer cell metabolic rewiring and targets for therapy.

7.
J Nanosci Nanotechnol ; 14(5): 3552-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734586

RESUMO

ZnO based bottom-gate thin film transistor (TFT) with SiO2 as insulating layer has been fabricated with two different structures. The effect of formation of mesa structure on the electrical characteristics of the TFTs has been studied. The formation of mesa structure of ZnO channel region can definitely result in better control over channel region and enhance value of channel mobility of ZnO TFT. As a result, by fabricating a mesa structured TFT, a better value of mobility and on-state current are achieved at low voltages. A typical saturation current of 1.85 x 10(-7) A under a gate bias of 50 V is obtained for non mesa structure TFT while for mesa structured TFT saturation current of 5 x 10(-5) A can be obtained at comparatively very low gate bias of 6.4 V.

8.
Pak J Biol Sci ; 16(5): 245-50, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24175435

RESUMO

The structural organization of different cells lining the olfactory epithelium of Gerres filamentosus (Cuvier 1829) were studied by light and scanning electron microscopy respectively to correlate their role in olfaction. The fan shaped olfactory rosette of G. filamentosus was more or less oval in outline and composed of 13 lamellae of different sizes in both sides. The olfactory epithelium was partitioned into sensory and non-sensory regions. The sensory epithelium was restricted on the flat apical end of the lamellae and embossed with two types of receptor cells bearing either cilia or microvilli. The non-sensory epithelium, covering the middle and basal region of lamellae was comprised of stratified epithelial cells and mucous cells. The orientation of various cells in the surface contour of olfactory epithelium was discussed in light of their functional significance.


Assuntos
Peixes/anatomia & histologia , Mucosa Olfatória/citologia , Animais , Cílios/fisiologia , Células Epiteliais/citologia , Olfato/fisiologia
9.
J Postgrad Med ; 59(1): 51-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23525059

RESUMO

A 26-year-old previously healthy female presented with a 6-month history of anemia. The laboratory findings revealed hemolytic anemia and direct antiglobulin test was positive. With a diagnosis of autoimmune hemolytic anemia (AIHA), prednisolone was started but was ineffective after 1 month of therapy. A bone marrow trephine biopsy revealed pure red cell aplasia (PRCA) showing severe erythroid hypoplasia. The case was considered PRCA following AIHA. This combination without clear underlying disease is rare. Human parvovirus B19 infection was not detected in the marrow aspirate during reticulocytopenia. The patient received azathioprine, and PRCA improved but significant hemolysis was once again documented with a high reticulocyte count. The short time interval between AIHA and PRCA phase suggested an increased possibility of the evolution of a single disease.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Medula Óssea/patologia , Aplasia Pura de Série Vermelha/diagnóstico , Adulto , Anemia Hemolítica Autoimune/tratamento farmacológico , Anemia Hemolítica Autoimune/imunologia , Azatioprina/administração & dosagem , Azatioprina/uso terapêutico , Biópsia , Teste de Coombs , Feminino , Humanos , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Aplasia Pura de Série Vermelha/tratamento farmacológico , Aplasia Pura de Série Vermelha/imunologia , Contagem de Reticulócitos , Resultado do Tratamento
10.
J Nanosci Nanotechnol ; 12(3): 1880-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22754993

RESUMO

We report the performance of the thin film transistors (TFTs) using ZnO as an active channel layer grown by radio frequency (RF) magnetron sputtering technique. The bottom gate type TFT, consists of a conventional thermally grown SiO2 as gate insulator onto p-type Si substrates. The X-ray diffraction patterns reveal that the ZnO films are preferentially orientated in the (002) plane, with the c-axis perpendicular to the substrate. A typical ZnO TFT fabricated by this method exhibits saturation field effect mobility of about 0.6134 cm2/V s, an on to off ratio of 102, an off current of 2.0 x 10(-7) A, and a threshold voltage of 3.1 V at room temperature. Simulation of this TFT is also carried out by using the commercial software modeling tool ATLAS from Silvaco-International. The simulated global characteristics of the device were compared and contrasted with those measured experimentally. The experimental results are in fairly good agreement with those obtained from simulation.

12.
Folia Morphol (Warsz) ; 70(3): 143-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21866523

RESUMO

The olfactory organ of Oreochromis nilotica was studied by means of light and scanning electron microscopes. The oval shaped olfactory apparatus consists of 19-20 lamellae radiating from a central raphe. The receptor epithelium occupies the restricted area of the middle swollen region of the lamellae and is framed with receptor cells (both ciliated and microvillous) and rod cells. The larger part of the lateral surface of the olfactory lamella is covered with non-receptor epithelium, which is made up of stratified epithelial cells and mucous cells. The functional significance of various cells lining the olfactory epithelium of this fish are discussed.


Assuntos
Ciclídeos/anatomia & histologia , Mucosa Olfatória/ultraestrutura , Neurônios Receptores Olfatórios/ultraestrutura , Animais , Microscopia Eletrônica de Varredura
13.
Folia Morphol (Warsz) ; 70(2): 74-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21630226

RESUMO

The olfactory epithelium of Scatophagus argus (Linnaeus) was investigated by light and scanning electron microscopy. The elongated olfactory organ is made up of 20 to 22 primary lamellae arranged on both sides of the narrow median raphe. Sensory and non-sensory regions are located separately on each lamella. The sensory epithelium occupies the upper apical broad half and extreme basal part of the olfactory lamellae whereas the middle slender part is covered with non-sensory epithelium. The sensory epithelium consists of ciliated, microvillus, and crypt cells. The non-sensory epithelium is made up of stratified epithelial cells having different patterns of finger-like micro-ridges and mucous cells. Different cells lining the olfactory epithelium have been correlated with the functional views of the fish concerned.


Assuntos
Mucosa Olfatória/ultraestrutura , Neurônios Receptores Olfatórios/ultraestrutura , Perciformes , Olfato/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Cílios/fisiologia , Cílios/ultraestrutura , Ecossistema , Microscopia Eletrônica de Varredura/métodos , Microvilosidades/fisiologia , Microvilosidades/ultraestrutura , Muco/metabolismo , Mucosa Olfatória/citologia , Mucosa Olfatória/fisiologia , Neurônios Receptores Olfatórios/fisiologia , Perciformes/anatomia & histologia , Perciformes/fisiologia , Especificidade da Espécie
14.
Br Poult Sci ; 52(6): 769-74, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22221243

RESUMO

1. Rice bran lysolecithin (RBL) was evaluated in broiler chicken diets. In the first experiment, RBL was included in diet at 0, 0·5, 2, 8 and 32 g/kg and fed to 250 broiler chickens from 0 to 42 d of age. In the second experiment, RBL was fed at 0, 25 and 50 g/kg diet to 405 day-old broiler chickens until 21 d of age, while during the finisher phase (22-35 d of age) chickens receiving each concentration of RBL were given all three concentrations of RBL in a 3 × 3 factorial manner. The diets were isocaloric. 2. Body weight, food consumption and food conversion efficiency were unaffected by feeding RBL, while the weight of pancreas increased at ≥2 g/kg of RBL in diet (experiment 1). In experiment 2, body weight was greater in the chickens receiving RBL at either 25 or 50 g/kg (21 d) and 50 g/kg (35 d of age). At 21 d of age, food consumption was greater at 25 or 50 g RBL/kg diet, while food conversion efficiency improved with 50 g RBL/kg diet. 3. Fat digestibility increased with RBL at 32 g/kg (experiment 1) and ≤25 g/kg (experiment 2). Rice bran lysolecithin increased ready to cook weight at 50 g/kg during starter phase and decreased abdominal fat at 25 and 50 g/kg during finisher phase (experiment 2). Liver and meat fat content were not affected. 4. It is concluded that lysolecithin from rice bran oil could be used as energy supplement in broiler chicken diet.


Assuntos
Galinhas/metabolismo , Lisofosfatidilcolinas/administração & dosagem , Carne/normas , Óleos de Plantas/administração & dosagem , Tecido Adiposo/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/fisiologia , Ingestão de Energia/fisiologia , Feminino , Fígado/metabolismo , Masculino , Tamanho do Órgão/fisiologia , Distribuição Aleatória , Óleo de Farelo de Arroz
15.
Folia Morphol (Warsz) ; 69(3): 154-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21154285

RESUMO

The cellular organisation of the olfactory rosettes of Etroplus suratensis was studied by light and scanning electron microscopy. The oval shaped olfactory rosette of the fish consists of 12 lamellae radiating from a central raphe. The olfactory lamellae are comprised of restricted areas of sensory epithelium and broad areas of non-sensory epithelium in the apical, middle, and basal regions. The sensory epithelium contains three types of receptor cells: microvillus, ciliated, and rod cells, as well as labyrinth cells and supporting cells. The non-sensory epithelium consists of stratified epithelial and mucous cells. The transitional region between the sensory and non-sensory epithelium consists of ciliated receptor cells, mucous cells, and stratified epithelial cells. The different cells on the olfactory epithelium were discussed regarding the functional significance of the fish concerned.


Assuntos
Ciclídeos/anatomia & histologia , Ciclídeos/fisiologia , Mucosa Olfatória/citologia , Mucosa Olfatória/fisiologia , Animais , Microscopia , Microscopia Eletrônica de Varredura , Microvilosidades/ultraestrutura , Mucosa Olfatória/ultraestrutura
16.
J Nanosci Nanotechnol ; 10(9): 5623-33, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21133083

RESUMO

Nanocrystalline NiFe2O4 with different particle sizes and nanocomposites of (NiFe2O4)(1-x)(Al2O3)x (x = 0.25, 0.40) were prepared by using co-precipitation method. In this method two techniques viz., 'ultrasonication' and 'magnetic stirring' during co-precipitation were used. The as prepared samples were annealed at different temperatures to obtain samples with different particle sizes. The formation of the nanocrystalline spinel phases of all the samples were confirmed by X-ray diffraction (XRD) patterns. The sizes of the nanoparticles of all the samples were calculated from the broadening of the (311) line in the XRD pattern. The distribution of sizes are remarkably less in samples obtained from 'ultrasonication' technique compared to those obtained in 'magnetic stirring' technique. The different soft magnetic quantities viz., coercive field, magnetization, remanance, hysteresis losses etc. were extracted from the ac hysteresis loops observed at different frequencies. The variations of coercive field and hysteresis loss as functions of frequency and particle sizes have been studied. Mössbauer spectra of the samples along with the hysteresis loops recorded at room temperature indicate the presence of superparamagnetic (SPM) relaxations of the nanoparticles. Also, SPM relaxations have been introduced in the samples annealed at higher temperature by encapsulating the nanoparticles in non-magnetic matrix of Al2O3 with 40% coating.

17.
Folia Morphol (Warsz) ; 69(1): 24-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20235046

RESUMO

The histological and micro-architecture of different cells lining the olfactory epithelium in Catla catla (Hamilton) have been studied by means of light and scanning electron microscopes. The oval olfactory rosette of the fish consists of a rosette of 30 to 32 primary lamellae. Each lamella is provided with restricted area of sensory epithelium in the middle region while the apical and basal part of the lamella consists of non-sensory epithelium. The non-sensory epithelium is made up of patches of ciliated supporting cells, epidermal or stratified epithelial cells with concentrically arranged microridges and scattered mucous cells. The sensory epithelium contains two types of receptor cell (microvillar and flagellated) and mucous cells. The multilayer olfactory organ in C. catla provides an acute sense of smell, and various aspects of their existence are mediated through olfactory cues.


Assuntos
Carpas/anatomia & histologia , Mucosa Olfatória/ultraestrutura , Animais , Carpas/fisiologia , Microscopia Eletrônica de Varredura , Mucosa Olfatória/fisiologia , Olfato/fisiologia
18.
Folia Morphol (Warsz) ; 68(1): 40-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19384829

RESUMO

The topological architecture and functions of different cells of the olfactory epithelium in Wallago attu (Bleeker) have been systematically studied using a scanning electron microscope. The elongated olfactory rosette of the fish consists of 62 to 64 primary lamellae in each left and right rosette. Each lamella is provided with apical sensory epithelium and basal non-sensory epithelium. Topological analysis reveals that sensory epithelium contains receptor cells, ciliated supporting cells, labyrinth cells, and goblet cells. The non-sensory epithelium is made up of patches of ciliated supporting cells, epidermal or stratified epithelial cells with concentrically arranged microridges, and scattered goblet cells. Different cells on the olfactory epithelium support the view that the olfactory signalling is important to the survival of this fish in an aquatic environment.


Assuntos
Peixes/anatomia & histologia , Mucosa Olfatória/fisiologia , Mucosa Olfatória/ultraestrutura , Animais , Peixes/fisiologia , Microscopia Eletrônica de Varredura/métodos , Bulbo Olfatório/ultraestrutura
19.
Indian J Med Res ; 129(2): 182-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19293446

RESUMO

BACKGROUND & OBJECTIVES: The diagnosis of bacterial meningitis remains a challenge to the clinician because of its rapid lethal course lacking the consistency to particular clinical signs and symptoms. Moreover, in many clinical settings use of rampant and short course antibiotic therapy prior to lumbar puncture reduces the chance of isolation of bacteria in CSF culture making the diagnosis difficult. The present study was done to evaluate a multiplex seminested PCR based method for rapid diagnosis of bacterial meningitis even after initiation of antibiotics. METHODS: A 16S rDNA based PCR technique was evaluated using universal bacterial primers to detect any bacterial pathogen in CSF samples. The simultaneous use of three species-specific primers in a multiplex and seminested PCR format was done to identify Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis within 4 h. RESULTS: Analysis of 267 CSF samples obtained from suspected cases of acute bacterial meningitis revealed 94 per cent concordance in results for conventional (Gram stain and culture) and molecular methods. Conventional techniques failed to detect five PCR positive samples where clinical diagnosis, cell count and biochemical findings of CSF supported the evidence of infection. The overall sensitivity, specificity, positive predictive value and negative predictive value of 16S rDNA PCR were 79.24, 97.6, 89.36 and 94.88 per cent respectively when culture was considered as gold standard. The detection limit of 16S rDNA PCR was determined to be 1000 cfu/ml of E. coli and 4000 cfu/ml of S. pneumoniae. INTERPRETATION & CONCLUSION: The results suggest that 16S rDNA PCR can be used as a valuable supplementary test in routine clinical practice for diagnosis of acute bacterial meningitis in hospital setting.


Assuntos
DNA Ribossômico/genética , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/genética , Análise de Variância , Primers do DNA/genética , Humanos , Índia , Meningites Bacterianas/líquido cefalorraquidiano , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
20.
Folia Morphol (Warsz) ; 66(1): 10-4, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17533588

RESUMO

The fine anatomical structures of the olfactory epithelium of Cyprinus carpio (Linnaeus) have been systematically studied with the help of the scanning electron microscope (SEM). The olfactory rosette is an oval structure composed of a number of lamellae arranged on a median raphe. A large part of the lateral surface of the rosette is covered with non-receptor epithelium, whereas the receptor epithelium occupies a much smaller area in the middle part. The nonreceptor epithelium is covered with a tuft of ciliated supporting cells, among which the stratified epithelial cells and mucous cells are located. The receptor epithelium is represented by the flagellated and microvillus receptor and supporting cells. Different cells on the olfactory epithelium correlate with the functional significance of the fish concerned.


Assuntos
Carpas/anatomia & histologia , Mucosa Olfatória/ultraestrutura , Animais , Cílios/ultraestrutura , Microscopia Eletrônica de Varredura , Mucosa Nasal/ultraestrutura , Neurônios/ultraestrutura , Mucosa Olfatória/inervação
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