432 research outputs found
Polymeric Recrystallized Agglomerates of Cefuroxime Axetil Prepared by Emulsion Solvent Diffusion Technique
Purpose: To study the effect of different polymers on the solubility and dissolution rate of cefuroxime axetil (CFU) prepared by emulsion solvent diffusion (ESD) technique.Methods: The ESD technique employed involved three test solvents: first, substance dissolution medium-good solvent (acetone); second, partial dissolution medium for the substance-bridging liquid (dichloromethane), and third, immiscible with the substance-poor solvent (distilled water). The pure CFU and the prepared agglomerates were characterized in terms of production yield, drug content, solubility, in vitro release profile, flowability, density, wettability, as well as by thin layer chromatography (TLC),differential scanning calorimetry (DSC), x-ray diffraction (XRD), Fourier transforms infra red spectroscopy (FTIR) and stability test.Results: DSC showed a decrease in the melting enthalpy indicating disorder in the crystalline content. XRD also indicated changes in crystallinity, FTIR revealed that there were no chemical changes in therecrystallized agglomerates while dissolution data demonstrated a marked increase in the dissolution rate (>55 % in 45 min) compared with the pure drug (35% in 45 min). The improvement in the dissolution rate of CFU from optimized crystal formulation was attributed to the wetting effect of the polymers, change in drug crystallinity, altered surface morphology and micronization. The recrystallized agglomerates also exhibited higher wettability and flowability. Conclusion: The optimised recrystallized agglomerates exhibited good solubility, wettability, dissolution rate and other physicochemical properties compared to the unmodified CFU
NEPHROPROTECTIVE ACTIVITY OF ASPARAGUS RACEMOSUS AGAINST CISPLATIN-INDUCED NEPHROTOXICITY AND RENAL DYSFUNCTION IN EXPERIMENTAL RATS
Objective: The current study was designed to evaluate the protective effect of standardized hydroalcoholic extract of Asparagus racemosus (AR) against cisplatin (CP)-induced nephrotoxicity in Wistar rats.Methods: AR extract was administered orally at three dose levels (100, 200, and 400 mg/kg). Vitamin E (250 mg/kg) was used as a standard nephroprotective agent. The kidney function test (estimation of serum creatinine, albumin, and blood urea nitrogen [BUN]), oxidative stress study (estimation of superoxide dismutase and malondialdehyde [MDA] activity), and histological examination of kidneys were conducted.Results: The efficacy of AR was compared with CP-treated group. Serum creatinine and BUN were significantly (p<0.001) elevated in CP-treated group compared to control group. Hydroalcoholic extract of AR (100, 200, and 400 mg/kg) and Vitamin E (250 mg/kg) significantly (p<0.001) decreased the serum creatinine and BUN levels. CP exhibited significant (p<0.001) decrease in albumin when compared to control. Significant (p<0.001) increase in the serum albumin level was found in extract-treated group compared to CP group. Significant (p<0.001) decrease in activity of superoxide dismutase (SOD) was observed in the CP group as compared to control. AR (100 and 200 mg/kg) significantly (p<0.01) increased SOD levels. AR (400 mg/kg) significantly (p<0.001) increased SOD levels. AR (100, 200, and 400 mg/kg) significantly (p<0.001) decreased MDA levels as compared to CP group. Histopathological examination of the kidneys showed that AR markedly ameliorated CP-induced renal tubular necrosis. Extract was found effective at all doses, although high dose (400 mg/kg) was found to be more effective and comparable with standard group (Vitamin E 250 mg/kg).Conclusion: The present investigation revealed that AR resulted in dose-dependent attenuation of CP-induced renal damage in rats
Socio-Demographic Patterning of Physical Activity across Migrant Groups in India: Results from the Indian Migration Study
OBJECTIVE: To investigate the relationship between rural to urban migration and physical activity (PA) in India. METHODS: 6,447 (42% women) participants comprising 2077 rural, 2,094 migrants and 2,276 urban were recruited. Total activity (MET hr/day), activity intensity (min/day), PA Level (PAL) television viewing and sleeping (min/day) were estimated and associations with migrant status examined, adjusting for the sib-pair design, age, site, occupation, education, and socio-economic position (SEP). RESULTS: Total activity was highest in rural men whereas migrant and urban men had broadly similar activity levels (p<0.001). Women showed similar patterns, but slightly lower levels of total activity. Sedentary behaviour and television viewing were lower in rural residents and similar in migrant and urban groups. Sleep duration was highest in the rural group and lowest in urban non-migrants. Migrant men had considerably lower odds of being in the highest quartile of total activity than rural men, a finding that persisted after adjustment for age, SEP and education (OR 0.53, 95% CI 0.37, 0.74). For women, odds ratios attenuated and associations were removed after adjusting for age, SEP and education. CONCLUSION: Our findings suggest that migrants have already acquired PA levels that closely resemble long-term urban residents. Effective public health interventions to increase PA are needed
Treatment options for severe hypertriglyceridemia (SHTG): the role of apheresis
Hypertriglyceridemia is associated with a number of severe diseases such as acute pancreatitis and coronary artery disease. In severe hypertriglyceridemia (SHTG, triglycerides > 1,000 mg/dL), rapid lowering of plasma triglycerides (TG) has to be achieved. Treatment regimes include nutritional intervention, the use of antihyperlipidemic drugs, and therapeutic apheresis. Apheretic treatment is indicated in medical emergencies such as hypertriglyceridemic pancreatitis
HIV-1 Promotes Renal Tubular Epithelial Cell Protein Synthesis: Role of mTOR Pathway
Tubular cell HIV-infection has been reported to manifest in the form of cellular hypertrophy and apoptosis. In the present study, we evaluated the role of mammalian target of rapamycin (mTOR) pathway in the HIV induction of tubular cell protein synthesis. Mouse proximal tubular epithelial cells (MPTECs) were transduced with either gag/pol-deleted NL4-3 (HIV/MPTEC) or empty vector (Vector/MPTEC). HIV/MPTEC showed enhanced DNA synthesis when compared with Vector/MPTECs by BRDU labeling studies. HIV/MPTECs also showed enhanced production of β-laminin and fibronection in addition to increased protein content per cell. In in vivo studies, renal cortical sections from HIV transgenic mice and HIVAN patients showed enhanced tubular cell phosphorylation of mTOR. Analysis of mTOR revealed increased expression of phospho (p)-mTOR in HIV/MPTECs when compared to vector/MPTECs. Further downstream analysis of mTOR pathway revealed enhanced phosphorylation of p70S6 kinase and associated diminished phosphorylation of eEF2 (eukaryotic translation elongation factor 2) in HIV/MPTECs; moreover, HIV/MPTECs displayed enhanced phosphorylation of eIF4B (eukaryotic translation initiation factor 4B) and 4EBP-1 (eukaryotic 4E binding protein). To confirm our hypothesis, we evaluated the effect of rapamycin on HIV-induced tubular cell downstream signaling. Rapamycin not only attenuated phosphorylation of p70S6 kinase and associated down stream signaling in HIV/MPTECs but also inhibited HIV-1 induced tubular cell protein synthesis. These findings suggest that mTOR pathway is activated in HIV-induced enhanced tubular cell protein synthesis and contributes to tubular cell hypertrophy
The significance of tumour microarchitectural features in breast cancer prognosis: a digital image analysis
BACKGROUND: As only a minor portion of the information present in histological sections is accessible by eye, recognition and quantification of complex patterns and relationships among constituents relies on digital image analysis. In this study, our working hypothesis was that, with the application of digital image analysis technology, visually unquantifiable breast cancer microarchitectural features can be rigorously assessed and tested as prognostic parameters for invasive breast carcinoma of no special type.
METHODS: Digital image analysis was performed using public domain software (ImageJ) on tissue microarrays from a cohort of 696 patients, and validated with a commercial platform (Visiopharm). Quantified features included elements defining tumour microarchitecture, with emphasis on the extent of tumour-stroma interface. The differential prognostic impact of tumour nest microarchitecture in the four immunohistochemical surrogates for molecular classification was analysed. Prognostic parameters included axillary lymph node status, breast cancer-specific survival, and time to distant metastasis. Associations of each feature with prognostic parameters were assessed using logistic regression and Cox proportional models adjusting for age at diagnosis, grade, and tumour size.
RESULTS: An arrangement in numerous small nests was associated with axillary lymph node involvement. The association was stronger in luminal tumours (odds ratio (OR) = 1.39, p = 0.003 for a 1-SD increase in nest number, OR = 0.75, p = 0.006 for mean nest area). Nest number was also associated with survival (hazard ratio (HR) = 1.15, p = 0.027), but total nest perimeter was the parameter most significantly associated with survival in luminal tumours (HR = 1.26, p = 0.005). In the relatively small cohort of triple-negative tumours, mean circularity showed association with time to distant metastasis (HR = 1.71, p = 0.027) and survival (HR = 1.8, p = 0.02).
CONCLUSIONS: We propose that tumour arrangement in few large nests indicates a decreased metastatic potential. By contrast, organisation in numerous small nests provides the tumour with increased metastatic potential to regional lymph nodes. An outstretched pattern in small nests bestows tumours with a tendency for decreased breast cancer-specific survival. Although further validation studies are required before the argument for routine quantification of microarchitectural features is established, our approach is consistent with the demand for cost-effective methods for triaging breast cancer patients that are more likely to benefit from chemotherapy
Drug sensitivity testing on patient-derived sarcoma cells predicts patient response to treatment and identifies c-Sarc inhibitors as active drugs for translocation sarcomas
BACKGROUND: Heterogeneity and low incidence comprise the biggest challenge in sarcoma diagnosis and treatment. Chemotherapy, although efficient for some sarcoma subtypes, generally results in poor clinical responses and is mostly recommended for advanced disease. Specific genomic aberrations have been identified in some sarcoma subtypes but few of them can be targeted with approved drugs. METHODS: We cultured and characterised patient-derived sarcoma cells and evaluated their sensitivity to 525 anti-cancer agents including both approved and non-approved drugs. In total, 14 sarcomas and 5 healthy mesenchymal primary cell cultures were studied. The sarcoma biopsies and derived cells were characterised by gene panel sequencing, cancer driver gene expression and by detecting specific fusion oncoproteins in situ in sarcomas with translocations. RESULTS: Soft tissue sarcoma cultures were established from patient biopsies with a success rate of 58%. The genomic profile and drug sensitivity testing on these samples helped to identify targeted inhibitors active on sarcomas. The cSrc inhibitor Dasatinib was identified as an active drug in sarcomas carrying chromosomal translocations. The drug sensitivity of the patient sarcoma cells ex vivo correlated with the response to the former treatment of the patient. CONCLUSIONS: Our results show that patient-derived sarcoma cells cultured in vitro are relevant and practical models for genotypic and phenotypic screens aiming to identify efficient drugs to treat sarcoma patients with poor treatment options.Peer reviewe
The Protein Phosphatase 7 Regulates Phytochrome Signaling in Arabidopsis
The psi2 mutant of Arabidopsis displays amplification of the responses controlled by the red/far red light photoreceptors phytochrome A (phyA) and phytochrome B (phyB) but no apparent defect in blue light perception. We found that loss-of-function alleles of the protein phosphatase 7 (AtPP7) are responsible for the light hypersensitivity in psi2 demonstrating that AtPP7 controls the levels of phytochrome signaling. Plants expressing reduced levels of AtPP7 mRNA display reduced blue-light induced cryptochrome signaling but no noticeable deficiency in phytochrome signaling. Our genetic analysis suggests that phytochrome signaling is enhanced in the AtPP7 loss of function alleles, including in blue light, which masks the reduced cryptochrome signaling. AtPP7 has been found to interact both in yeast and in planta assays with nucleotide-diphosphate kinase 2 (NDPK2), a positive regulator of phytochrome signals. Analysis of ndpk2-psi2 double mutants suggests that NDPK2 plays a critical role in the AtPP7 regulation of the phytochrome pathway and identifies NDPK2 as an upstream element involved in the modulation of the salicylic acid (SA)-dependent defense pathway by light. Thus, cryptochrome- and phytochrome-specific light signals synchronously control their relative contribution to the regulation of plant development. Interestingly, PP7 and NDPK are also components of animal light signaling systems
Gut Microbiota, Probiotics and Diabetes
Diabetes is a condition of multifactorial origin, involving several molecular mechanisms related to the intestinal
microbiota for its development. In type 2 diabetes, receptor activation and recognition by microorganisms from
the intestinal lumen may trigger inflammatory responses, inducing the phosphorylation of serine residues in insulin
receptor substrate-1, reducing insulin sensitivity. In type 1 diabetes, the lowered expression of adhesion proteins
within the intestinal epithelium favours a greater immune response that may result in destruction of pancreatic
β cells by CD8+ T-lymphocytes, and increased expression of interleukin-17, related to autoimmunity. Research in
animal models and humans has hypothesized whether the administration of probiotics may improve the prognosis
of diabetes through modulation of gut microbiota. We have shown in this review that a large body of evidence
suggests probiotics reduce the inflammatory response and oxidative stress, as well as increase the expression of
adhesion proteins within the intestinal epithelium, reducing intestinal permeability. Such effects increase insulin sensitivity and reduce autoimmune response. However, further investigations are required to clarify whether the administration of probiotics can be efficiently used for the prevention and management of diabetes
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