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1.
J Nanosci Nanotechnol ; 20(4): 2359-2364, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492248

RESUMO

The observations of room temperature ferroelectricity and ferromagnetism for GdMnO3 (GMO) ceramics have been reported in this paper. The nanocrystalline GMO powder was synthesized by chemical route and then sintered in the form of bulk pellet at 850 °C for 24 h by following slow step sintering schedule. Bulk GMO sample is observed to be polycrystalline in nature having orthorhombic perovskite structure and Pbnm space group. Well connected grains are observed with higher percentage of porosity in the micrographs obtained from field emission scanning electron microscope. The dielectric anomaly has been observed for the sintered sample at 338 K and a wide ferroelectric hysteresis loop has also been observed at room temperature. Room temperature dielectric constant (ε) value of the sample is high (~2736) at the frequency of 100 Hz. The zero field cooled (ZFC) and field cooled (FC) magnetizations shows the antiferromagnetic behavior around 12 K. Sample shows a weak ferromagnetic behavior at 3 K.

2.
Neuroscience ; 146(2): 741-55, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17367952

RESUMO

Exposure to environmental toxins increases the risk of neurodegenerative diseases including Parkinson's disease (PD). Rotenone is a neurotoxin that has been used to induce experimental Parkinsonism in rats. We used the rotenone model of experimental Parkinsonism to explore a novel aspect of extra-nigral degeneration, the neurodegeneration of spinal cord (SC), in PD. Rotenone administration to male Lewis rats caused significant neuronal cell death in cervical and lumbar SC as compared with control animals. Dying neurons were motoneurons as identified by double immunofluorescent labeling for terminal deoxynucleotidyl transferase, recombinant-mediated dUTP nick-end labeling-positive (TUNEL(+)) cells and choline acetyltransferase (ChAT)-immunoreactivity. Neuronal death was accompanied by abundant astrogliosis and microgliosis as evidenced from glial fibrillary acidic protein (GFAP)-immunoreactivity and OX-42-immunoreactivity, respectively, implicating an inflammatory component during neurodegeneration in SC. However, the integrity of the white matter in SC was not affected by rotenone administration as evidenced from the non co-localization of any TUNEL(+) cells with GFAP-immunoreactivity and myelin basic protein (MBP)-immunoreactivity, the selective markers for astrocytes and oligodendrocytes, respectively. Increased activities of 76 kD active m-calpain and 17/19 kD active caspase-3 further demonstrated involvement of these enzymes in cell death in SC. The finding of ChAT(+) cell death also suggested degeneration of SC motoneurons in rotenone-induced experimental Parkinsonism. Thus, this is the first report of its kind in which the selective vulnerability of a putative parkinsonian target outside of nigrostriatal system has been tested using an environmental toxin to understand the pathophysiology of PD. Moreover, rotenone-induced degeneration of SC motoneuron in this model of experimental Parkinsonism progressed with upregulation of calpain and caspase-3.


Assuntos
Calpaína/metabolismo , Caspase 3/metabolismo , Neurônios Motores/metabolismo , Degeneração Neural/metabolismo , Rotenona , Doenças da Medula Espinal/fisiopatologia , Animais , Antígeno CD11b/metabolismo , Colina O-Acetiltransferase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Proteína Básica da Mielina/metabolismo , Degeneração Neural/etiologia , Degeneração Neural/patologia , Fosfopiruvato Hidratase/metabolismo , Ratos , Ratos Endogâmicos Lew , Doenças da Medula Espinal/induzido quimicamente , Doenças da Medula Espinal/metabolismo , Doenças da Medula Espinal/patologia , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
3.
Int J Biol Macromol ; 93(Pt A): 1161-1167, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27667539

RESUMO

In this investigation an attempt has been made to characterize and identify Lysinibacillus sp. 3HHX by 16S-rDNA sequencing. The bacterium exhibited occurrence of PHAs granules on an average 11±1 per cell of 1.0µm length and breadth 0.72µm, revealed from TEM studies. Under optimized condition, 4.006gm/L of PHAs was extracted using hypochlorite digestion and multi-solvent extraction process. PhaC gene of ∼540bp and higher PHA synthase activity was detected at 48h of cultivation. The extracted PHAs was structurally characterized by GC-MS and 1H NMR reported to be P(3HB-co-3HDD-co-3HTD) and amorphous in nature with 112°C melting point, -11.0°C glass transition point and 114.76°C decomposition temperature detected by DSC & TGA respectively. The C/O of biopolymer disc was 1:65 as revealed from C1s and O1s spectra of XPS, that was completely biodegradable within 30 days. This biopolymer was observed to be non-cytotoxic to NIH 3T3 mouse fibroblast cells. The report is of its kind in establishing the abilities of Lysinibacillus sp. 3HHX for non-growth associated PHA co-polymer production. Moreover the biocompatible and biodegradable nature of the biopolymer conferred to its substantial biomedical applications.


Assuntos
Bacillaceae/metabolismo , Fermentação , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Imersão , Camundongos , Células NIH 3T3 , Poli-Hidroxialcanoatos/metabolismo , Poli-Hidroxialcanoatos/toxicidade , Rizosfera , Microbiologia do Solo
4.
Biotechnol Adv ; 18(2): 91-120, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14538112

RESUMO

Well developed techniques are currently available to help growers meet the demand of the pharmaceutical industry in the next century. These protocols are designed to provide optimal levels of carbohydrates, organic compounds (vitamins), mineral nutrients, environmental factors (e.g. light, gaseous environment, temperature, and humidity) and growth regulators required to obtain high regeneration rates of many plant species in vitro and thereby facilitate commercially viable micropropagation. Well-defined cell culture methods have also been developed for the production of several important secondary products. An overview of the regeneration of medicinal plants by direct and indirect organogenesis and by somatic embryogenesis from various types of explants is presented, and the use of these techniques combined with other biotechnological approaches to improve medicinal plants through somaclonal variation and genetic transformation is reviewed.

5.
Int J Parasitol ; 20(7): 969-72, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2276870

RESUMO

Studies were conducted on 41 cross-bred (Bos taurus x Bos indicus) calves which were less than 1 year old. Three types of salivary gland antigens (SG Ag) viz. SG Ag-I (whole), SG Ag-II (supernatant) and SG Ag-III (sediment), prepared from the ixodid tick, Hyalomma anatolicum anatolicum, were used for immunizing these calves. The calves were divided into five groups. The first three groups were immunized with SG Ag-I, -II and -III with Freund's complete adjuvant (FCA), respectively. The fourth group was immunized with SG Ag-I (without adjuvant), and the fifth group remained as an unimmunized control inoculated with FCA only. In all the groups, immunization was carried out on days 1 and 14 and the animals were challenged on the 21st day. Significant resistance developed in the calves of the SG Ag-I and SG Ag-II (both with FCA) groups. Of all, SG Ag-I with FCA proved the most potent immunogen. Both humoral and cellular immune responses were demonstrated by in vivo and in vitro tests. The capillary tube agglutination test and double diffusion test gave positive reactions 21 days after first immunization. The immunized calves showed a significant increase in the levels of serum gamma globulin and per cent 'E' rosettes. Tick salivary gland antigens therefore seem to have promising potentials in inducing resistance in calves.


Assuntos
Antígenos/imunologia , Doenças dos Bovinos/prevenção & controle , Imunização/veterinária , Infestações por Carrapato/veterinária , Carrapatos/imunologia , Animais , Bovinos , Masculino , Glândulas Salivares/imunologia , Infestações por Carrapato/prevenção & controle
6.
J Cancer Res Clin Oncol ; 130(1): 37-44, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14569466

RESUMO

PURPOSE: Matrix metalloproteinases (MMPs) are known to play an important role in extracellular matrix remodeling during the process of tumor invasion and metastasis. However, little is known about their role in preinvasive lesions and early esophageal carcinomas. METHOD: Immunohistochemical analysis of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) expression was carried out in paraffin-embedded sections of surgically resected esophageal squamous cell carcinoma (ESCC) (58 cases) and paired distal normal esophageal tissues (44 cases) and correlated with clinicopathological parameters. RESULT: Overexpression of MMP-2 and MMP-9 proteins was observed in 39 (67%) and 32 (55%) of the 58 ESCCs, respectively localized in tumor cell cytoplasm and stromal elements. Histological evaluation of hematoxylin- and eosin-stained 44 matched distal normal esophageal tissue sections revealed that 26 comprised of normal epithelium, while 15 tissues showed evidence of dysplasia and three tissues showed hyperplasia. Interestingly, 12 (80%) and 13 (87%) of these 15 dysplasias showed immunostaining for MMP-2 and MMP-9 proteins, respectively. Low levels of MMP-2 and MMP-9 were observed in 10 (38%) and 6 (23%) of 26 matched histologically normal esophageal tissues, respectively. Higher MMP-2 immunopositivity was observed in well and moderately differentiated SCCs in comparison with poorly differentiated tumors. The expression of MMP-2 was significantly reduced with the progressive de-differentiation of esophageal SCCs ( P =0.03). Overexpression of MMP-2 and MMP-9 in dysplasia as well as SCC suggests that these alterations occur in early stages of esophageal tumorigenesis. CONCLUSION: Increased levels of MMP-2 and MMP-9 proteins in ESCCs as compared to normal esophageal tissues suggest their association with esophageal tumorigenesis. Increased levels of these MMPs are observed in majority of dysplasias analyzed herein, indicating that these alterations may be early events in esophageal tumorigenesis. In-depth studies are warranted to determine their role in development and progression of esophageal cancer.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/enzimologia , Neoplasias Esofágicas/enzimologia , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Adulto , Western Blotting , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Esôfago/enzimologia , Esôfago/patologia , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Hiperplasia/enzimologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Regulação para Cima
7.
Plant Cell Rep ; 16(8): 578-582, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-30727582

RESUMO

Somatic embryogenesis was achieved in callus cultures dervied from 40-day-old semimature zygotic embryos ofDalbergia sissoo on semi-solid Murashige and Skoog (MS) salts and vitamins supplemented with 0.46-1.16 µM kinetin, 6.78-9.04 µM 2,4-dichlorophenoxy acetic acid (2,4-D) and 30 g/1 sucrose. Somatic embryos proliferated rapidly by secondary somatic embryogenesis after transfer to half-strength basal MS medium supplemented with 0.46-1.16 µM kinetin and 6.78-9.04 µM 2,4-D with 2% (w/v) sucrose. The light-green somatic embryos germinated on half-strength MS salts and vitamins supplemented with 0.5 mg/1 abscisic acid and 2% (w/v) sucrose. The developmental stages of somatic embryogenesis were studied by light and scanning electron microscopy.

8.
Vet Parasitol ; 31(1): 83-7, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2499092

RESUMO

The relative role of male and female Hyalomma anatolicum anatolicum ticks in the epidemiology of Theileria transmission was studied by detecting Theileria sporozoites in the dissected salivary glands of 568 ticks by the methyl green pyronin staining method. Detailed frequency distribution of Theileria-positive acini in the salivary glands of the 264 (46.48%) positive ticks from a field collection in Haryana indicated that the number of infected salivary acini per positive tick was greater in females than in males. This suggests that female ticks have a more important role in Theileria transmission than male ticks. This finding assumes greater significance in the light of the observation that the natural male:female ratio is also in favour of female ticks.


Assuntos
Apicomplexa/fisiologia , Vetores Aracnídeos/parasitologia , Theileriose/transmissão , Carrapatos/parasitologia , Animais , Bovinos , Feminino , Interações Hospedeiro-Parasita , Índia , Masculino , Fatores Sexuais
9.
Environ Pollut ; 98(1): 29-36, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-15093342

RESUMO

This review emphasises cadmium toxicity on plants with regards to ecological, physiological and biochemical aspects. Cadmium toxicity in plants and problems concerning tolerance and ecological performance are discussed briefly. Efforts have been made to compare the relative sensitivity of various plant groups including micro-and macro-flora. This review may help in interdisciplinary studies to assess the ecological significance of metal stress.

10.
Chemosphere ; 40(8): 855-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10718579

RESUMO

The tolerance of populations of a grass, Echinochloa colona, growing abundantly on chromite minewaste dumps, was tested in two separate experiments. Seed-based experiments indicate that the populations growing naturally on uncontaminated sites, germinated better in nutrient solutions without metal than those collected from minewaste dumps. Metal tolerance indices were greater in the plant populations derived from metal contaminated sites and better growth of these plants was noted on mine spoil soil-mix in the ratio of 1:1; the percentage of seed germination and the rate of seedling growth, however, declined in a soil compost containing 25% mine spoil and 75% uncontaminated (control) soil. Populations of Echinochloa colona occurring naturally on chromite mine spoils, therefore, appear to have developed metal tolerance. It is maintained by a balanced and stable genetic system built up and adjusted by natural selection. Such material is very suitable to be used in restoration work designed to produce an effective vegetation cover to improve the derelict land and to reduce erosion. This finding might be useful in revegetation programmes on metalliferous minewastes.


Assuntos
Cromo/toxicidade , Germinação/efeitos dos fármacos , Níquel/toxicidade , Poaceae/fisiologia , Poluentes do Solo/toxicidade , Resíduos Perigosos , Mineração , Poaceae/crescimento & desenvolvimento
11.
Environ Technol ; 22(10): 1147-54, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11766037

RESUMO

Metal contamination in soil and plant samples from a chromite mine and its adjoining regions was determined. The metal concentration varied in stem, leaf and root of different tree species. In the case of shrubs, the highest concentration of iron (18.5 mg kg(-1) was detected in the stem of Combretum roxburghii. The concentration of aluminium varied from 1.8 - 5.3 mg kg(-1) dry weight, whereas the nickel content was found to be the highest in the stem of Calotropis gigantea. In the case of herbs, chromium concentration was highest (60.9 mg kg(-1) dry weight) in Evovulus alsenoides and the lowest (18.8 mg kg(-1) dry weight) in Andrographis paniculata. There was a significant correlation observed between chromium in soil with the root of tree species like Lagerstroemia parviflora, Madhuca longifolia, Anogeissus latifolia and Haldina cordyfolia. Nickel in soil was significantly correlated with the stem and leaf of all the tree species except Chlroxylon sweitenta. Iron in soil showed correlation with the stem and leaf of Chloroxylon sweitenia. Among the shrubs (Calotropis gigantea, Combretum roxburghii and Smilax zeylancia), chromium in soil showed a correlation with the root. Nickel in soil was positively correlated with the stem and leaf of Calotropis gigantea and Combretum roxburghii. Among the herbs, chromium in the whole plant of Evolvulus alsenoids, Solanum surattense and Phyllanthus fraternus showed significant positive correlation with soil; nickel in Solanum surattense showed significant positive correlation with soil. The positive correlation coefficient was observed between iron in the whole plant and soil on Phyllanthus virgatus, Phyllanthus fraternus and Andrographis paniculata. The above information would be useful for the establishment of a vegetation cover on the minewaste heaps.


Assuntos
Cromo , Monitoramento Ambiental , Metais Pesados/análise , Mineração , Plantas/química , Poluentes do Solo/análise , Ecossistema , Metais Pesados/farmacocinética , Eliminação de Resíduos , Poluentes do Solo/farmacocinética
12.
Indian J Pathol Microbiol ; 44(1): 63-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12562001

RESUMO

Sertoli cell tumours are rare sexcord stromal tumours of testis. Malignant behaviour is observed in one tenth of such tumours. A malignant sertoli cell tumour is reported here in a 70 years old man. The tumour was of large size and showed necrosis, marked celllar pleomorphism, and mitotic figures.


Assuntos
Tumor de Células de Sertoli/patologia , Neoplasias Testiculares/patologia , Idoso , Humanos , Masculino , Tumor de Células de Sertoli/complicações , Neoplasias Testiculares/complicações
13.
Rev Biol Trop ; 49(3-4): 957-63, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12189827

RESUMO

A successful protocol was developed for mass propagation of Lawsonia inermis Linn., an important medicinal plant. Multiple shoots were induced in apical and axillary meristems derived from mature explants of L. inermis on Murashige and Skoog (1962) medium supplemented with 0.25 mg/l 6-benzylaminopurine (BA), 0.25 mg/l Kinetin (Kn), 0.5 mg/l ascorbic acid and 3% (w/v) sucrose. The rate of multiplication was higher when the cultures were incubated under continuous light rather than the 14 hr photoperiod. Rooting was readily achieved upon transferring the microshoots onto MS basal semi-solid medium supplemented with 0.25 mg/l indole-3-butyric acid (IBA) after ten days of culture. Micropropagated plantlets were acclimatized and successfully grown in soil.


Assuntos
Lythraceae/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Aclimatação , Meios de Cultura , Lythraceae/fisiologia , Brotos de Planta/fisiologia , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/fisiologia , Reprodução
14.
J Parasit Dis ; 37(1): 1-10, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24431532

RESUMO

Sarcocystis spp. are a group of tissue cyst-forming coccidia which infect a vast range of animals as well as human beings. Found frequently in animal carcasses at slaughter, undermining their value, they have also been found associated with clinical disease. Dogs and cats are involved in the transmission. Studies in India point to a vast reservoir of infection with high prevalence rates in various livestock species. However, there is a glaring paucity of reports on the horse and Sarcocystis of the camel has remained totally unexplored so far. At least two different Sarcocystis spp. can parasitize each livestock host species. Experimental transmission studies have provided additional parameters for distinguishing the species. The clinical symptoms are generally non-specific and diagnosis in the living animal, by the presently available means, is almost impossible. Immunodiagnosis till now is beset with problem of cross-reactivity. Treatment with anti-coccidials presently tried do not seem satisfactory. Of the two zoonotic species with cattle-man and pig-man cycles, only the latter seems of some significance in India due to backyard pig-rearing and slaughter practices. It is a paradox that despite high prevalence of S. suihominis in pigs, reports of human cases are limited. This and some of the existing grey areas of information in the Indian context, have been highlighted as also possible directions for future research.

15.
Neuroscience ; 192: 263-74, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21723922

RESUMO

Parkinson's disease (PD), characterized by selective midbrain nigrostriatal dopaminergic degeneration, is consistently associated with moderate systemic mitochondrial dysfunction. Downstream degeneration of spinal cord has also been suggested in PD, although the mechanisms have not been much investigated. In the present study, two mitochondrial toxicants, 1-methyl-4-phenylpyridinium ion (MPP(+)) and rotenone were tested in ventral spinal cord (VSC 4.1) motoneuronal cells. Cell death was assessed by morphological and biochemical means to discern a lower apoptosis-inducing concentration and lethal concentration of 50% cell death (LC(50)), which were subsequently compared in further cytoprotection experiments. Mitochondrial toxicants dose-dependently induced increase in intracellular free Ca(2+) level, which was conducive for increased expression and activities of Ca(2+)-activated neutral protease calpain and downstream caspase-3. Thus, mitochondrial damage triggered apoptotic mechanisms in spinal cord motoneurons. Inhibition of calpain by calpeptin significantly attenuated damaging effects of MPP(+) and rotenone on motoneurons, especially at low apoptosis-inducing concentrations of toxicants and partly at their LC(50), as demonstrated by absence of DNA ladder formation and decrease in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Cytoprotection by calpeptin was observed with marked decreases in Bax: Bcl-2 ratio and activities of calpain and caspase-3, which affirmed the role of mitochondrial dysfunction and involvement of intrinsic pathway in mediation of apoptosis. These findings strongly suggested that parkinsonian toxicants MPP(+) and rotenone at low doses induced cascade of cell-damaging effects in spinal cord motoneurons, thus, highlighting the possibility of induction of apoptotic mechanisms in these cells, when subjected to mitochondrial stress. Cytoprotection rendered by calpeptin further validated the involvement of calpain in apoptosis and suggested calpain inhibition as a potential neuroprotective strategy.


Assuntos
Calpaína/antagonistas & inibidores , Neurônios Motores/efeitos dos fármacos , Desacopladores/toxicidade , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Western Blotting , Linhagem Celular , Inibidores de Cisteína Proteinase/farmacologia , Dipeptídeos/farmacologia , Células Híbridas , Marcação In Situ das Extremidades Cortadas , Camundongos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Rotenona/toxicidade , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia
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