Ingestion of microplastics and its potential for causing structural alterations and oxidative stress in Indian green mussel Perna viridis- A multiple biomarker approach.

The present study has investigated the distribution of microplastics in sediment and its impact on histological, ultrastructural, and oxidative stress mechanisms in Perna viridis (P. viridis) from Kasimedu, Chennai, India. The results confirmed that fibers were the predominant type of microplastics observed, followed by spheres, flakes, sheets, and fragments. The observed microplastics were confirmed as polyester, polypropylene, polyethylene, cellophane, and rayon using µ-FT-IR. Microplastic particles entangled in gills caused abrasion of ciliated structure and hemocyte infiltration in the hemolymph vessels. The digestive gland showed a shrunken nucleus, dark inclusions, and damage in the nucleoid core structure. Enlarged vacuoles and the presence of clusters of vesicles presumably represented the transformed golgi cisternae. Further, the results confirmed that oxidative stress markers were significantly high in gills and digestive diverticula of P. viridis. Overall, the results indicated that microplastics induced different toxic physiological and structural alterations in gills and digestive diverticula of P. viridis. These findings highlighted the necessity to focus on exposure studies to understand the absolute magnitude of the problem due to microplastic pollution in the urban estuarine ecosystems of Chennai, Tamil Nadu, India.

Epidemiology of Invasive Fungal Infections at Two Tertiary Care Neonatal Intensive Care Units Over a 12-Year Period (2000-2011).

We conducted a retrospective review of 168 patients with invasive fungal infections from January 2000 to December 2011 in 2 neonatal intensive care units. Patients with Candida bloodstream infection (BSI, n = 152) were further analyzed. C albicans was the most common species overall (47%); however, there was an increase in non-albicans sp from 2006 to 2011. Candida BSI clearance rates were lower in extremely low birth weight infants (77% vs 93%, P = .01) and in patients with C albicans infections (77% vs 91%, P = .01). Clearance rates improved from 2000 to 2005 (70% - 90%) to 2006 to 2011 (86% -100%). Combination antifungal use increased during the later years (73% vs 49%, P < .05) and in patients with end-organ dissemination (83% vs 54%, P < .05). We concluded that extremely low birth weight infants and C albicans infection are factors associated with nonclearance of Candida BSI. Successful clearance of Candida BSI improved in 2006 to 2011, perhaps due to increase in non-albicans species and the use of combination antifungals.

Microfilariae recurrence in graded murrah buffalo treated with repeated doses of ivermectin.

Filariosis is one of the common parasitic diseases of animals and man caused by a small group of filarid nematodes throughout the world. This disease is highly prevalent in hot and humid arenas of India especially hilly parts of Tarai region of Uttar Pradesh and coastal areas of Andhra Pradesh, (Kumar et al. 2005). Microfilariosis is manifested by pyerxia, loss of appetite, reduced milk yield, weakness, edema of dependent parts. Macrofilaricidal and micerfilaricidal are the most effective drugs to get rid of the larvae and adult worm burden. Ivermectin 200 µg/kg body wt subcutaneous route is used as a curative drug in present clinical case and animal was responded well with the treatment. After 2 months the animal brought with same symptoms which were reported earlier. Wet blood film examination revealed recurrence of microfilariae in the peripheral blood circulation.

How well are we preparing pediatricians to manage seizures and epilepsy? A single-center questionnaire-based pilot study.

OBJECTIVE: To assess the knowledge of pediatric residents regarding principles of management of seizures and epilepsy. METHODS: A 10-item multiple-choice questionnaire with single correct response each (scored as 1) was administered to pediatric residents at an academic hospital. RESULTS: Out of 92 questionnaires, 73 were returned (79.3%). The mean score was 5 ± 1.9 (range = 1 to 9). Most correct responses (53/70, 75.5%) were received for the question on diagnosis of epilepsy. Questions on febrile seizures and on pharmacology of valproic acid received <50% correct responses among senior as well as junior residents, with no significant improvement in the correct response rate of senior residents. CONCLUSIONS: Deficiencies exist in pediatric residents' knowledge of seizures and epilepsy, especially with respect to febrile seizures and pharmacology of antiepileptic medications. Improved mechanisms to promote understanding in these areas are needed during pediatric training.

Influence of estradiol on mammary tumor collagen solubility in DMBA-induced rat mammary tumors.

Estradiol plays a vital role in the growth and development of mammary glands. It is a potent stimulator of metabolic processes in normal and carcinoma breast. A critical factor in determining mammary glandular morphology is the stroma. Collagen is a predominant component of the extracellular matrix and cell-collagen interactions are essential carcinogenesis. The present investigation explored the influence of estradiol on collagen solubility and metabolism in mammary tumors during tumor progression and regression. A single injection of 20 mg of 9,10-dimethyl-1,2-benzanthracene was given to rats at 7 weeks of age. With the appearance of the first palpable mammary tumor, the rats were treated with 0.5 microg estradiol or 50 microg tamoxifen daily for 30 days. The rats were sacrificed 24 h after 30 days of treatment. Estradiol appears to stimulate the synthesis of new collagens and thus contributes to the enlargement of the mammary tumors. This might have created a potential microenvironment by increasing the synthesis of suitable matrix that sustains the growth of the mammary tumors. In short, the present findings emphasize a definite mediatory role for collagen in estradiol promoted mammary tumor growth.

Identification of rat mammary tumor-1 gene (RMT-1), which is highly expressed in rat mammary tumors.

Full-term pregnancy early in life results in a permanent reduction in lifetime breast cancer risk in women. Parous rats and mice are also refractory to chemical carcinogenesis. Therefore, investigation of the differences between mammary glands from virgin and parous rats would provide valuable information regarding the protective effects of early full-term pregnancy. In this report, we examined the gene expression patterns in mammary glands from virgin and parous Lewis rats. Using differential display technology, a novel 4.2 kb cDNA, designated rat mammary tumor-1 (RMT-1) was isolated. Northern blot analysis of RMT-1 showed that RMT-1 expression was higher in the pre-pubertal and pubertal stages during rat mammary gland development while it was down-regulated in mammary glands from mature virgin and parous rats. RMT-1 expression was highest in rat mammary cancers compared with either the mammary glands of virgin or parous rats. At the Northern blot sensitivity level, RMT-1 expression was found only in the mammary gland. Northern blot analysis also showed that the expression of this gene was found in 74% of N-methyl-nitrosourea (MNU)-induced mammary cancers while it was not found in MNU-induced cancers from other organs. The examination of the RMT-1 gene structure revealed that it consists of five exons spanning 5.9 kb. Using fluorescence in situ hybridization, the gene was localized on rat chromosome 1 band q 43-51. The present data show that there is a correlation between high RMT-1 expression and rat mammary carcinogenesis or decreased RMT-1 expression and parity associated refractoriness to chemically induced mammary carcinogenesis. However, whether or not RMT-1 gene has a functional role in these processes remains to be investigated.

Short-term exposure to pregnancy levels of estrogen prevents mammary carcinogenesis.

It is well established that pregnancy early in life reduces the risk of breast cancer in women and that this effect is universal. This phenomenon of parity protection against mammary cancer is also observed in rodents. Earlier studies have demonstrated that short-term administration of estradiol (E) in combination with progesterone mimics the protective effect of parity in rats. In this study, the lowest effective E dosage for preventing mammary cancer was determined. Rats were injected with N-methyl-N-nitrosourea at 7 weeks of age; 2 weeks later, the rats were subjected to sustained treatment with 20 microg, 100 microg, 200 microg, or 30 mg of E in silastic capsules for 3 weeks. Treatments with 100 microg, 200 microg, and 30 mg of E resulted in serum levels of E equivalent to those of pregnancy and were highly effective in preventing mammary cancer. E treatment (20 microg) did not result in pregnancy levels of E and was not effective in reducing the mammary cancer incidence. In another set of experiments, we determined the effect of different durations of E with or without progesterone treatments on mammary carcinogenesis. These experiments indicate that a period as short as one-third the period of gestation is sufficient to induce protection against mammary carcinogenesis. The pioneering aspect of our study in contrast to long-term estrogen exposure, which is thought to increase the risk of breast cancer, is that short-term sustained treatments with pregnancy levels of E can induce protection against frank mammary cancer.

Hormonal prevention of breast cancer: mimicking the protective effect of pregnancy.

Full term pregnancy early in life is the most effective natural protection against breast cancer in women. Rats treated with chemical carcinogen are similarly protected by a previous pregnancy from mammary carcinogenesis. Proliferation and differentiation of the mammary gland does not explain this phenomenon, as shown by the relative ineffectiveness of perphenazine, a potent mitogenic and differentiating agent. Here, we show that short term treatment of nulliparous rats with pregnancy levels of estradiol 17beta and progesterone has high efficacy in protecting them from chemical carcinogen induced mammary cancers. Because the mammary gland is exposed to the highest physiological concentrations of estradiol and progesterone during full term pregnancy, it is these elevated levels of hormones that likely induce protection from mammary cancer. Thus, it appears possible to mimic the protective effects of pregnancy against breast cancer in nulliparous rats by short term specific hormonal intervention.

Increased degradation of dermal collagen in diabetic rats.

The effect of alloxan induced diabetes on the dermal collagen content of albino rats was studied in relation to few lysosomal enzymes. Diabetes decreased the dermal collagen content. The specific activities of the lysosomal enzymes studied in the diabetic rat skin were elevated. It has been established that lysosomal enzymes degrade the connective tissue components. Thus, it may be suggested that the increase in the lysosomal enzymes studied should have facilitated the decrease in dermal collagen content of diabetic rats by increasing the degradation of dermal collagen.