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This work is focused on the development of controlled drug delivery systems using different wax/fat embedded indomethacin (IM). Discrete wax/fat embedded microspherules containing indomethacin were prepared by using cetostearyl alcohol, paraffin wax and stearic acid by employing emulsification-phase separation method. These matrices have been used as barrier coatings due to their hydrophobic nature. Chemically inert and tasteless nature of wax/fats promotes their use as taste masking agents for bitter drugs. Various waxes and fats are available having different physicochemical properties to suit the needs of formulation. Methyl cellulose (MC) 1% w/v, sodium alginate (SA) 0.5% w/v and Tween-80 (TW) 1% w/v were used as emulgents. The resulting microspherules were discrete, large, spherical and also free flowing. It is revealed from the literature that natures of wax/fat emulgents were found to influence the rate of drug release. In the present work the drug content in all the batches of microspherules were found to be uniform. The rate of drug release corresponded best to first order kinetics, followed by Higuchi and zero-order equations. The release of the model drug from these wax/fat microspherules was prolonged over an extended period of time and the drug release mechanism followed anomalous (non-Fickian) diffusion controlled as well as Super Case II transport. Among the three matrix materials used, paraffin wax retarded the drug release more than the other two. Surface characteristics of microspherules have been studied by Scanning Electron Microscope (SEM). A fair degree rank of correlation was found to exist between the size and release retardation in all the three-wax/fat emulgent combinations.  相似文献   
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Background

Variants of DNA repair genes are extensively reported to cause genetic instability and increase the risk of breast cancer. In combination with NBS1, MRE11 and RAD50 constitute an MRN (MRE11–RAD50–NBS1) complex that repairs DNA damage. However, certain genetic alterations in MRE11 and RAD50 produce abnormal protein that affects the repairing process and may result in malignancy. We aimed to investigate the association of MRE11 and RAD50 polymorphisms with breast risk in the female population of Punjab, Pakistan.

Methods

We collected blood samples of 100 breast cancer patients and 100 tumor-free females selected as controls. Extracted DNA was genotyped by tetra ARMS-PCR followed by gel electrophoresis. Results were analyzed by SPSS and SNPstats to analyze the association of different clinical factors and SNPs (single nucleotide polymorphisms) with the risk of breast cancer.

Results

We found that the increased risk of breast cancer is associated with MRE11 variant rs684507 (odds ratio-OR 3.71, 95% confidence interval-CI 1.68–8.18, p value < 0.0001), whereas, RAD50 variant rs28903089 appeared to have protective effect (OR 0.55, CI 0.29–1.02, p value = 0.003). Additionally, clinical factors such as positive family history, life style, and marital status also play significant roles in breast cancer development.

Conclusion

In the present study, strong risk of breast cancer was associated with MRE11 gene. However, RAD50 showed protective effect. Additionally, clinical factors are also pivotal in risk assessment. We anticipate that targeting specific genetic variations confined to ethnic groups would be more effective in future therapeutic approaches for prevention and treatment of breast cancer.
  相似文献   
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Purpose of Review

Rectal cancer is predominantly a disease of older adults but current guidelines do not incorporate the associated specific challenges leading to wide variation in the delivery of cancer care to this subset of population. Here, we will review the current data available regarding the management of rectal cancer in older adults.

Recent Findings

The greatest challenge arises in the management of stage II/III disease as it involves tri-modality treatment that can be harder to tolerate by frail older patients. Response to neoadjuvant treatment is being used as a new marker to tailor further therapy and possibly avoid surgery. Oxaliplatin can be omitted from the adjuvant treatment without compromising outcomes.

Summary

Physicians should perform geriatric assessment utilizing many validated tools available to help predict treatment tolerability and outcomes in older adults that can help personalize subsequent management. Most older adults can undergo standard therapy for stages I, II, or III rectal cancer with curative intent. Increasing evidence suggests that patients with a clinical complete response to neoadjuvant treatment may be observed closely with the possibility of avoiding surgery. Studies are evaluating alternate systemic treatments for advanced metastatic disease with the hope of maintaining quality of life without compromising cancer outcomes.
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Gender, race/ethnicity, and personality are markers of significant psychosocial and biological variability. Each may have implications for allostatic load and resulting inflammatory processes, yet findings have been largely mixed. We investigated whether women, minorities, and those higher in Neuroticism and lower in Extraversion were at risk for elevated circulating levels of the pro-inflammatory cytokine interleukin (IL)-6 in a sample of 103 middle aged and older urban primary care patients. Regression analyses controlling for age, education, current depression levels, and chronic medical conditions revealed that women, minorities, and individuals lower in Extraversion had higher circulating levels of IL-6. Analyses of more specific personality traits revealed that the sociability and positive emotions components of Extraversion were unassociated with IL-6, but the activity facet—reflecting dispositional vigor and energy—was robustly associated with IL-6. The difference between high (+1 Standard Deviation (SD)) and low (?1 SD) trait activity was sufficient to shift IL-6 levels beyond a previously established high risk cut-point in both white and minority women. These findings suggest that while broad group differences between genders and races/ethnicities exist, personality represents an important source of individual differences in inflammation within groups. Future work should examine to what extent IL-6 levels are linked to temperament or genetic activity levels vs. physical activity itself, and whether IL-6 levels may be reduced by boosting regular activity levels in demographic segments such as women and minorities who appear susceptible to greater inflammation.  相似文献   
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