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1.
Indian J Dent Res ; 30(5): 703-707, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31854360

RESUMO

Background: Oral cytology studies have claimed that cytoplasmic Periodic Acid Schiff (PAS) positivity in type-2 diabetics is due to glycogen content. But, it can also be due to mucin and glycoconjugates. Aim: 1. To confirm that cytoplasmic PAS positivity in type-2 diabetics is due to glycogen using diastase. 2. To know the effect of diabetes by determining the number of glycogen-containing cells in the smear. 3. To assess the impact of duration of diabetes based on PAS staining of cells. 4. To correlate between random blood glucose level and the number of PAS-positive cells. Materials and Methods: Study population comprised 45 individuals with 30 type-2 diabetics as case group (Group I < 5 years duration; Group II > 5 years duration) and 15 healthy volunteers (age and gender-matched) as control. For all subjects, random blood glucose was estimated and two cytosmears were obtained. The smears were stained with PAS and PAS-diastase stains (PAS-D). Staining intensity was documented as score 1 (mild-to-moderate) and score 2 (moderate-to-intense) and data obtained were statistically analyzed in SPSS version 16.0. Results: Mann-Whitney U test revealed that in diabetics cytoplasmic PAS positivity is because of glycogen (P < 0.05). There is an increase in the number of glycogen-containing cells (P < 0.05) in diabetics. The duration of diabetes had less impact on intracellular glycogen accumulation (P > 0.05). Spearman's correlation test revealed no significant correlation (P > 0.05) between random blood glucose and a number of PAS-positive cells. Conclusion: PAS positivity is because of intracellular glycogen accumulation in type-2 diabetics. It can convey the glycaemic status of an individual in the recent past, thus a beneficial role in screening and therapeutic monitoring.


Assuntos
Diabetes Mellitus , Glicogênio , Glicemia , Corantes , Humanos , Reação do Ácido Periódico de Schiff , Coloração e Rotulagem
2.
J Oral Maxillofac Pathol ; 23(Suppl 1): 27-31, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30967719

RESUMO

The presence of numerous minor salivary gland tissues in the posterior part of hard palate increases the possibility of salivary gland neoplasms. Minor salivary gland tumor accounts for about 15% of all the salivary gland neoplasms, of which mucoepidermoid carcinoma (MEC) accounts for about 35.9%. Although a wide range of the differential diagnosis is made by the clinicians toward a single palatal swelling without any other specific changes on inspection, a prompt "histopathological" diagnosis is of utmost importance in case of lesions like "MEC." By taking the case study of a 23-year-old male patient who was complaining of difficulties in eating and speaking due to a swelling in the palate that was not associated with pain, etc., this case report highlights the need for an early clinical examination and prompt histopathological diagnosis of such clinically benign looking lesions, as such an action can play an ameliorating role in reducing the chances of postoperative morbidity.

3.
J Biomol Struct Dyn ; 37(11): 2875-2896, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30043685

RESUMO

Here, a theoretical and comprehensive study of the structural features and interaction properties of viral protein 40 is being briefed out to understand the mechanism of Ebola virus (EV) with structural and orbital analysis. In general, viral protein 40 is the key protein for the oligomerization, the N-terminal loop region in the viral protein 40 and it is essential for the viral replication in Ebola. The electronic structures of native N-terminal loop (His124-Asn134) and metalized (Mn+=Ag+ and Cu2+) complexes are optimized at the M06-2X/LANL2DZ level of theory. Among Mn+-interacted N-loop complexes, Cu2+-interacted N-terminal loop complex has the highest interaction energy of -973.519 kcal/mol and also it has the stabilization energy in the range of 9.92 kcal/mol. The cation-π interactions between His124, Pro131 and Arg134 residues are the important factor, which enhances the interaction energy of viral protein 40. Due to the chelation behavior of metal ions, the backbone and the side chains of N-terminal loop regions are deviated from the planarity that results in the formation of classical hydrogen bonds between N-terminal loop regions. Molecular dynamics simulation studies also revealed that the structural transformations of Nloop into a stable α-helix and ß-sheet folded conformations due to the interaction of Ag+ and Cu2+ ions in the N-terminal loop region. The hydrogen bond formation and hydrophobic interactions are responsible for the stability and structural changes in N-terminal loop region. Therefore, it is clear that interaction of metal ion with viral protein-40 reduces the replication of the disease by inducing the secondary structural changes. Communicated by Ramaswamy H. Sarma.

4.
Hum Exp Toxicol ; 35(2): 170-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25829403

RESUMO

Despite the extensive use of nanoparticles (NPs) in various fields, adequate knowledge of human health risk and potential toxicity is still lacking. The human lymphocytes play a major role in the immune system, and it can alter the antioxidant level when exposed to NPs. Identification of the hazardous NPs was done using in vitro toxicity tests and this study mainly focuses on the comparative in vitro cytotoxicity and genotoxicity of four different NPs including cobalt (II, III) oxide (Co3O4), iron (III) oxide (Fe2O3), silicon dioxide (SiO2), and aluminum oxide (Al2O3) on human lymphocytes. The Co3O4 NPs showed decrease in cellular viability and increase in cell membrane damage followed by Fe2O3, SiO2, and Al2O3 NPs in a dose-dependent manner after 24 h of exposure to human lymphocytes. The oxidative stress was evidenced in human lymphocytes by the induction of reactive oxygen species, lipid peroxidation, and depletion of catalase, reduced glutathione, and superoxide dismutase. The Al2O3 NPs showed the least DNA damage when compared with all the other NPs. Chromosomal aberration was observed at 100 µg/ml when exposed to Co3O4 NPs and Fe2O3 NPs. The alteration in the level of antioxidant caused DNA damage and chromosomal aberration in human lymphocytes.


Assuntos
Óxido de Alumínio/toxicidade , Cobalto/toxicidade , Compostos Férricos/toxicidade , Linfócitos/efeitos dos fármacos , Nanopartículas/toxicidade , Óxidos/toxicidade , Dióxido de Silício/toxicidade , Adulto , Antioxidantes/metabolismo , Membrana Celular/patologia , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
5.
Prep Biochem Biotechnol ; 46(5): 446-53, 2016 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26444052

RESUMO

Polyhydroxyalkanoate (PHA) is a promising polymer for various biomedical applications. There is a high need to improve the production rate to achieve end use. When a cost-effective production was carried out with cheaper agricultural residues like molasses, traces of toxins were incorporated into the polymer, which makes it unfit for biomedical applications. On the other hand, there is an increase in the popularity of using chemically defined media for the production of compounds with biomedical applications. However, these media do not exhibit favorable characteristics such as efficient utilization at large scale compared to complex media. This article aims to determine the specific nutritional requirement of Pseudomonas sp. MNNG-S for efficient production of polyhydroxyalkanoate. Response surface methodology (RSM) was used in this study to statistically design for PHA production based on the interactive effect of five significant variables (sucrose; potassium dihydrogen phosphate; ammonium sulfate; magnesium sulfate; trace elements). The interactive effects of sucrose with ammonium sulfate, ammonium sulfate with combined potassium phosphate, and trace element with magnesium sulfate were found to be significant (p < .001). The optimization approach adapted in this study increased the PHA production more than fourfold (from 0.85 g L(-1) to 4.56 g L(-1)).


Assuntos
Poli-Hidroxialcanoatos/metabolismo , Pseudomonas/metabolismo , Fermentação
6.
J Biomed Mater Res A ; 102(10): 3470-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24222470

RESUMO

The focus of this study was to evaluate the growth of the cells on a scaffold based on novel polyhydroxyalkanoate (PHA) (Polyhydroxy propionate copoly hydroxy ocatadecanoate copolymer), derived from a mutant strain of Pseudomonas sp. Naive PHA was also blended with several biodegradable polymeric materials (PEG, PLA, and MMT) to improve the scaffold properties. Protein adsorption study was done to evaluate the capability of scaffolds for cellular interaction. PHA:PEG blended scaffold showed better adsorption than others. 3T3 fibroblast cultures on various polymers were equally viable when compared with control culture except for the blend PHA:MMT by CCK 8 kit. MTT assay, performed with the continuous cultures HeLa, HEp-2, Vero, and McCoy on the polymer blends, supported the above finding. Among the blends PHA:PEG showed increased viability and was selected for further studies. Cell proliferation assay with colorimetric BrdU ELISA kit showed increase in cell proliferation over the matrix PHA:PEG than that of control. There were no observable morphological changes of continuous cells grown over matrix PHA:PEG when observed by phase contrast microscopy. HEp-2 cells were enclosed within the matrix when analyzed by SEM. The current study states that the scaffold prepared by using the indigenous PHA in combination with PEG supports cell growth better than the conventional plastic surface. PHA:PEG would be a promising material for tissue engineering.


Assuntos
Materiais Biocompatíveis/farmacologia , Fibroblastos/citologia , Poli-Hidroxialcanoatos/farmacologia , Células 3T3 , Adsorção , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Pseudomonas/metabolismo , Soroalbumina Bovina/metabolismo , Solventes
7.
Curr Microbiol ; 65(5): 589-94, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22875103

RESUMO

Polyhydroxyalkanoates (PHAs) are natural polyesters produced by microbes, a potential alternative to synthetic plastics. Various methods ranging from gravimetry to spectrophotometry are routinely used for qualitative analysis of extracted PHA. There is a great need for accurate quantification of intracellular PHA during bioprocess. Hence, the present study aims to improvise the existing Nile red-based flow cytometry protocol. It was achieved using respective cells in a non-PHA accumulating state as gating control to minimize non-specific staining. The optimal Nile red concentration required for PHA staining is 5 × 10(3) pg mL(-1), which is ~10(3)-fold less than that of earlier reports. Further, it was inferred that flow-based quantification was more accurate than the gravimetric method. The intracellular PHA content was highest in Pseudomonas sp. MNNG-S (52.06 %) among the Pseudomonas strains tested by the flow-based method. Both gravimetric and flow-based cell cycle analyses revealed that DNA synthesis (S phase) and PHA production (log phase) are synchronous at 24-48 h of culture. This study supports flow-based PHA quantification for real time online measurement of intracellular PHA for bioreactor monitoring, control and optimization enduing industrial applications.


Assuntos
Citometria de Fluxo/métodos , Poli-Hidroxialcanoatos/análise , Pseudomonas/química , Pseudomonas/metabolismo , Reatores Biológicos/microbiologia , Poli-Hidroxialcanoatos/metabolismo
8.
Braz. j. microbiol ; 42(3): 1109-1118, July-Sept. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-607542

RESUMO

Polyhydroxyalkanoates (PHA) are biodegradable and biocompatible green thermoplastics, synthesized by wide variety of bacteria as an intracellular carbon and energy storage intermediate. They are used as an alternative to nonrenewable petroleum derived plastics. The current interest in these biopolyesters is stimulated by the search for cost-effective capitalized production. This paper attempts to achieve maximized production rate from recombinant system using inexpensive substrate. Molasses from agro-industrial waste was used to produce PHA from recombinant E.coli in batch culture. PHA yield in molasses (3.06g/L ± 0.05-75.5 percent) was higher than that of sucrose (2.5g/L ± 0.05 - 65.1 percent). Properties of the polymer produced from molasses and sucrose were analyzed by DSC, TGA, DTA, GC/MS, TLC and optical rotation studies. The findings suggested that molasses enhanced PHA production in recombinant E.coli.


Assuntos
Biopolímeros/análise , Proteínas de Escherichia coli , Melaço/análise , Pseudomonas , Poli-Hidroxialcanoatos/análise , Polímeros/análise , Sacarose/análise , Biodegradação Ambiental , Métodos , Técnicas
9.
Braz J Microbiol ; 42(3): 1109-18, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24031729

RESUMO

Polyhydroxyalkanoates (PHA) are biodegradable and biocompatible green thermoplastics, synthesized by wide variety of bacteria as an intracellular carbon and energy storage intermediate. They are used as an alternative to nonrenewable petroleum derived plastics. The current interest in these biopolyesters is stimulated by the search for cost-effective capitalized production. This paper attempts to achieve maximized production rate from recombinant system using inexpensive substrate. Molasses from agro-industrial waste was used to produce PHA from recombinant E.coli in batch culture. PHA yield in molasses (3.06g/L ± 0.05‒75.5%) was higher than that of sucrose (2.5g/L ± 0.05 - 65.1%). Properties of the polymer produced from molasses and sucrose were analyzed by DSC, TGA, DTA, GC/MS, TLC and optical rotation studies. The findings suggested that molasses enhanced PHA production in recombinant E.coli.

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