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Abstract : Increased Incidence of Breast Cancer Due to Long Exposure of Light
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Abstract: The disturbed circadian rhythm due to long exposure to varied photo periods or to artificial light during night time (LAN) results in hormonal imbalance. The epidemiological survey indicates a clear difference in the incidence of breast cancer (BC) in countries closer to the poles and to the equator. Long-term exposure to LAN during sleep cycle is found to be the root cause of many health problems. Light dependent conversion of melatonin from serotonin plays a major role in cancer development. In rat model it is shown that levels of melatonin are always inversely proportional to oestradiol in the blood. Melatonin decreases the formation of oestrogens (mitogenic hormone) from androgens via aromatise inhibition. In a pilot study we have shown that in menopausal blind (risk age for BC) women the prevalence of BC is very low (1:169; Risk Rate (RR); Cumulative Risk (CR)35-64 age), compared to sighted women (1:78; CR, 35 - 64 age). Data was collected from a total of 2060 blind subjects (18.8% being <40 years of age and 81.2% above 40 years). Partially blind subjects have 11% greater risk of developing BC than those who are totally blind (RR=1.106; 95% CI=.352 to 3.472). Other established risk factors for BC are ineffective in blind. The blind women model (proposed in this study) suggests that dark hours are essential in our daily routine. By management of proper circadian rhythms better management of various endocrine diseases including hormone dependent cancers can be achieved. Keywords: Blind women model, low incidence, photoperiod, melatonin, epidemiology.Download Full Article |
Abstract : Depth-Sensitive Raman Spectroscopy of Intact Formalin-Fixed and Paraffin-Embedded Tissue Blocks for Objective Diagnosis of Cancer- An Exploratory Study
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Abstract: Histopathology, the current “gold standard”, is prone to human errors as it depends on expert interpretation of the microscopically derived cellular and sub-cellular information for tissue diagnosis. Further, this light microscope based approach requires preparation of appropriately stained specimens of micro-thin tissue sections from the formalin-fixed and paraffin-embedded (FFPE) blocks of tissue samples. We report a method that provides quantitative feedback about tissue diagnosis by measuring depth-sensitive Raman spectra from the intact FFPE tissue blocks without requiring preparation of any thin tissue sections or any other processing. The FFPE blocks of pathologically certified cancerous and normal breast tissues were used for validating the approach. The measured depth-sensitive Raman spectra were mathematically de-paraffinized for retrieving the characteristic tissue Raman signatures using scaled-subtraction. A multivariate analysis of the scaled-subtracted, depth-sensitive Raman spectra employing a probability-based diagnostic algorithm developed using the framework of sparse multinomial logistic regression (SMLR) provided a sensitivity and specificity of up to 100% towards cancer based on leave-one-block-out cross validation. The results of this exploratory study suggest that depth-sensitive Raman spectroscopy along with a multivariate statistical algorithm can provide a valuable alternate diagnostic modality in clinical pathology setting for discriminating cancerous from normal FFPE tissue blocks. Keywords: Formalin-fixed and paraffin-embedded (FFPE) tissue blocks, Depth-sensitive Raman spectroscopy, Scale-subtraction.Download Full Article |
Abstract : Microwaves Devulcanization of SBR Containing Carbon Black
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Abstract: Polymer recycling has been the most suitable alternative for management of plastics waste that are responsible by serious environmental damages. However, the recycling of some polymer materials, such as vulcanized elastomers, is not a trivial process. The recycling of elastomers is a process more complex than the recycling of thermoplastic polymers because the elastomers cannot be remolded by simple heating after vulcanization. Methods for rubber devulcanization has been developed as an interesting alternative for recover flow properties of elastomers, allowing other molding cycle. The aim of this work was to evaluate the effect of the presence of carbon black on devulcanization of styrene-butadiene rubber (SBR) by microwaves and analyze properties of recycled material. The devulcanization by microwaves showed efficiency for rubber compositions with higher content of carbon black incorporated as well as the properties of recycled material showed satisfactory performance for reuse in other products. Microwaves devulcanization of SBR is an important alternative for reuse of rubber waste and decrease of the environmental problem generated with discard of these materials. Keywords: Devulcanization, microwaves, rubber recycling.Download Full Article |
Abstract : The Influence of Pigment Transfer on the Risk of Developing Melanoma: The Significance of the Melanocyte ‘Amputation Cycle’
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Abstract: It has been shown that cancer incidence is not only a function of the size of the population at risk but is strongly associated with the turnover rate of the tissue concerned. There is a strong negative correlation between melanoma incidence and the degree of skin pigmentation, and yet the melanocyte density is the same for all races. The proposal advanced in this communication is that the probability of undergoing malignant change is critically dependent on the melanocyte turnover and that this is regulated by the pigmentation process. In melanocytes, the division rate is influenced by the process of pigment donation, probably by a mechanism whereby the continual cytoplasmic loss due to cytocrine transfer of melanosomes (termed the ‘Amputation Cycle’) inhibits replication. Consequently the turnover of melanocyte stem cells in heavily pigmented epidermis will be diminished, and this is held to account for the strong negative correlation between the degree of skin pigmentation and melanoma incidence. Download Full Article |
Abstract : Most Commonly Isolated Bacteria in Urine and their In Vitro Sensitivity to Antibiotics in Men with Benign Prostatic Hyperplasia
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Abstract: Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms commonly affect older men. Men with BPH in Podgorica in almost half (47.5%) cases have positive urine culture, out of which 14.2% have polyinfection. Urinary tract infections are most common in the age group 71 to 80 years. Although both groups of men (with and without BPH) are more prone to gram-negative bacterial infections of the urinary tract, K. pneumoniae is significantly more common in men with BPH compared with men without BPH. The results indicate that treatment of men with BPH is much more complex than in men without BPH due to the fact that in the treatment, a number of strains are resistant to levofloxacin (resistance of gram-negative bacteria to levofloxacin at the level of 80.4%, with 89.7% of resistant strains of K. pneumoniae and 73.3% of E. coli strains, as well as resistance of gram-positive bacteria at level of 24.8%, with resistant strains of enterococci in 64.7% of the strains) and β-lactam antibiotics (53.4% of isolated gram-negative bacteria synthesize ESBL enzymes out of which K. pneumoniae in up to 89.7% of the strains). Also, men with BPH have multi drug resistant strains in 53.1% of gram-positive bacteria and 79.7% of gram-negative bacteria. Carbapenems still represent a reserve group of drugs that have a good therapeutic effect in 93.2% of urinary tract infections in men with BPH. Download Full Article |