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1.
Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC50 and IC90) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.  相似文献   
2.
Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6?×?100?mm, 3.5?µm) UPLC column. The optimized chromatographic condition was achieved at 0.16?mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235?nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt?=?2.723 and 3.068?min, respectively along with r2?>?0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis.  相似文献   
3.
Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) are autoimmune mediated diseases triggered by group A streptococcal (GAS) infections. Molecular mimicry between GAS M-proteins and host tissue proteins has been proposed as the mechanism that initiates autoreactive immune responses in ARF/RHD. However, the individual role of antibodies and T-cells specific for GAS M-proteins in the pathogenesis of autoimmune carditis remains under-explored. The current study investigated the role of antibodies and T-cells in the development of carditis in the Lewis rat autoimmune valvultis (RAV) model by transferring serum and/or splenic T-cells from rats previously injected with GAS recombinant M5 protein. Here we report that serum antibodies alone and serum plus in vitro expanded rM5-specific T-cells from hyperimmune rats were capable of transferring carditis to naïve syngeneic animals. Moreover, the rats that received combined serum and T-cells developed more severe carditis. Recipient rats developed mitral valvulitis and myocarditis and showed prolongation of P-R intervals in electrocardiography. GAS M5 protein-specific IgG reactivity and T-cell recall response were also demonstrated in recipient rats indicating long-term persistence of antibodies and T-cells following transfer. The results suggest that both anti-GAS M5 antibodies and T-cells have differential propensity to induce autoimmune mediated carditis in syngeneic rats following transfer. The results highlight that antibodies and effector T-cells generated by GAS M protein injection can also independently home into cardiac tissue to cross-react with tissue proteins causing autoimmune mediated immunopathology.  相似文献   
4.
A study on the current oscillation based on the electrogenerated superoxide ion (O2-) at a hanging mercury drop electrode (HMDE) in dimethylsulfoxide solution containing tetra-n-alkylammonium perchlorate as the electrolyte was carried out. Cyclic voltammetric, potential step chronoamperometric, normal and reverse pulse voltammetric techniques were employed in this study. A bare glassy carbon electrode, a liquid hemispherical mercury (Hg) drop-coated gold (Au) electrode and a Hg film-coated Au electrode were also used as working electrodes to understand the mechanism of the current oscillation. The experimental conditions were optimized for a simple, regular and reproducible current oscillation. The specific adsorption phenomenon of iodide ion and the adsorption of the alkyl chain of the supporting electrolyte on the HMDE surface were also considered to clarify the experimental factors governing the current oscillation phenomenon. It has been concluded that the oscillation is mainly due to the promoted oxidation (dissolution) of the HMDE itself by the adsorption of O2-, resulting in the formation–destruction of a passive film such as Hg2(O2-)2 on the electrode surface. A probable mechanism for the observed current oscillation is discussed.  相似文献   
5.
Inadequate diet quality is a cause of undernutrition among children 6–23 months of age in Bangladesh, particularly in remote and isolated areas such as Bandarban District. Feeding animal source foods can help to combat stunting and wasting problems among children, but it may not be accessible or acceptable. A barrier analysis using the Designing for Behavior Change Framework was conducted in Bandarban district with participants from 4 ethnic groups, to explore potential barriers and key motivators by examining 12 behavioural determinants of consumption of animal-source food in complementary feeding for children 8–23 months. Data were collected from 45 mothers of children 8–23 months, who provided animal-source foods to their children (doers), and from 45 mothers who did not (non-doers), for a total of 90 interviews. Nine determinants were statistically significantly different between doers and non-doers as follows: self-efficacy, positive consequences, negative consequences, social norms, access, reminders, perceived risk, perceived severity and perceived action efficacy. Nearby access to purchase animal-source foods, rearing poultry or livestock at home and the support of household and community members are enablers to feeding animal-source food. In contrast, these same factors are barriers for non-doers. The lack of money to spend on animal-source foods is also a barrier. An integrated nutrition-sensitive and gender-transformative animal-based food production, and inclusive market programme could increase access to meat and eggs at the household level, increase opportunities to earn income and support gender-equitable household workloads and decision-making for optimal child feeding.  相似文献   
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8.
Patchouli oil, an essential aroma oil extracted from patchouli leaf during short-term exposure with five and ten drops either inhibited (at 1 or 2 h) or stimulated (at 4 h) the platelet MAO-A activity depending on the dosages of the aroma oil mainly due to inhibition or stimulation of its K m. The long-term 15 consecutive days exposure (with two or five drops) of patchouli oil, on the other hand, maximally stimulated the platelet MAO-A activity with five drops patchouli oil for 1 h exposure, but further continuation of its exposure with same doses (two or five drops) for 30 consecutive days significantly stimulated (with two drops) and inhibited (with five drops) the platelet MAO-A activity due to stimulation and inhibition respectively of its corresponding both K m and V max. These results thus suggest that this aroma oil exposure may modulate the blood platelet serotonergic regulation depending on the dose, duration, and conditions of exposure.  相似文献   
9.
Background: Triple negative breast cancer (TNBC) which is treated with taxane, adriamycin and cyclophosphamide (TAC) chemotherapy regimen show variation in treatment response. CYP1B1 4326 C>G polymorphism has been implicated in contributing to the differences in treatment response in various types of cancers. Aim: The objective of the present study was to investigate whether this polymorphism modulate the risk of disease recurrence in TNBC patients undergoing TAC chemotherapy regimen. Methods: Blood samples of 76 immunohistochemistry confirmed TNBC patients were recruited. The genotyping of CYP1B1 4326 C>G polymorphism was carried out using PCR-RFLP technique. The genotype patterns were categorized into homozygous wildtype, heterozygous and homozygous variant. Kaplan-Meier analysis followed by Cox proportional hazard regression model were performed to evaluate the TNBC patients’ recurrence risk. Results: Out of 76 TNBC patients, 25 (33.0%) showed disease recurrence after one-year evaluation. Kaplan Meier analysis showed that TNBC patients who are carriers of CYP1B1 4326 GG variant genotypes (37.0%) had a significantly lower probability of disease-free rates as compared to TNBC patients who are carriers of CYP1B1 4326 CC/CG genotypes (71.0%). Univariate and multivariate Cox analysis demonstrated that TNBC patients who carried CYP1B1 4326 GG variant genotype had a significantly higher risk of recurrence with HR: 2.50 and HR: 4.18 respectively, even after adjustment as compared to TNBC patients who were carriers of CYP1B1 4326 CC and CG genotypes. Conclusion: Our results demonstrate the potential use of CYP1B1 4325 GG variant genotype as a candidate biomarker in predicting risk of recurrence in TNBC patients undergoing TAC chemotherapy regimen.  相似文献   
10.

Objective

In developing countries like Bangladesh, delayed presentation for disorders of sex development (DSD) is common, and provides some special problems for management. There remains significant controversy about appropriate sex assignment in this group. We aimed, therefore, to assess gender identity (GI) in 50 consecutive patients with DSD presenting to a referral centre in Chittagong, Bangladesh, and correlate it with Prader score, to see if the latter could be used to predict GI.

Methods

A cross-sectional, case–control study of 50 consecutive children with DSD and 50 children with vascular anomalies was conducted in the Pediatric Surgical Clinic, Chittagong Medical College and Hospital. After informed consent, patients and controls provided oral answers to a GI questionnaire and had a detailed history and physical examination. Sex-typed activities were assessed by observations of a structured toy play and the child’s selection of a toy to keep. Both patients and parents then completed the Child Game Participation Questionnaire.

Results

There were no differences in age (2–16 years, mean 8.74) between controls and DSD patients (11 46, XX DSD, 32 46, XY DSD, 4 MGD, 3 ovo-testicular DSD). Fifteen of the DSD patients (30 %) came from consanguineous marriages and only 2 of the control patients had consanguinity of their parents. For the 13-question GI interview, there was no overall difference between DSD cases and controls. For the 46, XX DSD subgroup, there was a significantly higher score (11.1 ± 7.1) compared with control girls (4.5 ± 4.7) (p < 0.05), while for DSD and control boys, there was a positive correlation with age and GI (p < 0.01). Prader score correlated with GI score in both control (r = 0.91) and DSD patients (r = 0.75) (p < 0.01), DSD girls played significantly less with girls’ toys than controls (p < 0.01), but there was no differences for the boys. Composite scores on GI and gender-related behaviour correlated with Prader score for DSD patients (r = 0.61) (p < 0.01).

Conclusion

This study supports the view that GI and gender-role behaviour should be assessed routinely in DSD patients presenting after the neonatal period, so that sex assignment is in accordance with behaviour. Prader scores showed a good correlation with GI and gender role behaviour.  相似文献   
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