Comparison between Conventional Gastric Adenocarcinoma and EBV Associated Gastric Carcinoma

Epstein Barr Virus (EBV or Human herpesvirus 4) belongs to the genus Lymphocryptoviridae, the gamma 1 subtype of the Subfamily Gamma herpes viridae and is one of the most common viruses in humans. It is present in all populations, infecting more than 95% of all individuals within the first four decades of life. In developing countries, infections occur very early in life with no specific characteristics other than the general symptoms of acute viremia. In developed countries however, the infection is usually delayed until adolescence or early childhood years where it causes infectious mononucleosis, a benign self-limiting lymphoproliferative disorder.Though the infection with EBV is benign in the acute stages and latent in the chronic phase in the vast majority of people, the virus has been demonstrated to be involved in the development of many malignancies with the list of such malignancies progressively increasing. The first association was with the endemic Burkitt’s lymphoma. Subsequently, other lymphomas (subtypes of Hodgkin’s and non-hodgkin’s lymphomas) are also known to be associated with EBV infection. Epithelial malignancies such as lymphoepitheliomas of nasopharynx and stomach are included in the list of EBV associated tumors. Tumors arise as a result of genetic and epigenetic alterations produced by the virus, which transforms the normal cell into an immortalized proliferating cell. Since Burke et al first detected EBV in undifferentiated lymphoepithelioma like gastric cancer in 1990, many researches are undertaken to prove the same. EBV expresses latent membrane protein which can be detected immune histochemically.Our study is aimed at detecting the EBV expression in gastric carcinoma cells

Assessment of knowledge and practice on plastics among the professional course students of Annamalai University, Tamil Nadu

Background: The use of plastics made life easy in day to day life. However, the disposal of it remains a public health problem worldwide. Plastic waste are major cause of environment pollution becomes carcinogenic to human, birth defects, impaired immunity, endocrine disruption, development and reproductive effect. Raising the awareness of the different stake holders is suggested by United Nations Environment Programme. Assessing the knowledge and practice of the student community, especially of the professional courses, in this regard is considered as a vital one.Methods: A total of 563 students of professional courses were included in the study. Their knowledge in terms general aspects, ill effects, reuse and practice in terms of usage and disposal were assessed with a questionnaire.Results: 46% of the students found having good knowledge. Only 27.6% were found to have good practice. Though the students have good knowledge on ill effects of plastics, their practice in terms of disposal was less. Significant variations were observed among the students of different courses.Conclusions: Addressing the gap between knowledge and practice in terms of designing messages for proper disposal and avoiding usage of single use plastics at individual and collective level is required.

Osteoblast response to commercially available demineralized bone matrices - An in-vitro study.

Objective: Reconstruction of lost attachment apparatus is a major goal of periodontal therapy. Although various osteoinductive bone replacement grafts (BRGs) have been used with apparent clinical success, unequivocal evidence of osteoinductivity may be obtained only through the demonstration of increased osteoblastic/osteoclastic differentiation following exposure to these materials. Materials and Methods: Bone marrow stem cells (BMSCs) obtained from rat femur were cultured in Dulbecco's Modified Eagles Medium (DMEM) and 10% fetal bovine serum (FBS). They were then exposed to two demineralized bone matrices (DBM's) - Grafton and Osseograft, and divided into three groups, comprising of a negative control (BMSC + DMEM + 10% FBS), Grafton, Osseograft. An osteogenic medium (OM) (10 hm dexamethasone, 10 hm b-glycerophosphate, and 50 μg/ml ascorbic acid) was added to create three subgroups comprising of a positive control (OM), Grafton with OM, Osseograft with OM. Results: After an initial phase (up to day 5), both Grafton and Osseograft induced an increased proliferative activity in the BMSCs, which reached a plateau after day 10. These grafts also induced increased alkaline phosphatase activity when compared to the control groups and to BMSCs with an OM. Conclusion: Both Osseograft and Grafton are capable of inducing osteoblastic proliferation and differentiation.

Analysis on sliding helices and strands in protein structural comparisons: a case study with protein kinases.

Protein structural alignments are generally considered as 'golden standard' for the alignment at the level of amino acid residues. In this study we have compared the quality of pairwise and multiple structural alignments of about 5900 homologous proteins from 718 families of known 3-D structures. We observe shifts in the alignment of regular secondary structural elements (helices and strands) between pairwise and multiple structural alignments. The differences between pairwise and multiple structural alignments within helical and beta-strand regions often correspond to 4 and 2 residue positions respectively. Such shifts correspond approximately to "one turn" of these regular secondary structures. We have performed manual analysis explicitly on the family of protein kinases. We note shifts of one or two turns in helix-helix alignments obtained using pairwise and multiple structural alignments. Investigations on the quality of the equivalent helix-helix, strand-strand pairs in terms of their residue side-chain accessibilities have been made. Our results indicate that the quality of the pairwise alignments is comparable to that of the multiple structural alignments and, in fact, is often better. We propose that pairwise alignment of protein structures should also be used in formulation of methods for structure prediction and evolutionary analysis.

Comparison of sequence-based and structure-based phylogenetic trees of homologous proteins: Inferences on protein evolution.

Several studies based on the known three-dimensional (3-D) structures of proteins show that two homologous proteins with insignificant sequence similarity could adopt a common fold and may perform same or similar biochemical functions. Hence, it is appropriate to use similarities in 3-D structure of proteins rather than the amino acid sequence similarities in modelling evolution of distantly related proteins. Here we present an assessment of using 3-D structures in modelling evolution of homologous proteins. Using a dataset of 108 protein domain families of known structures with at least 10 members per family we present a comparison of extent of structural and sequence dissimilarities among pairs of proteins which are inputs into the construction of phylogenetic trees. We find that correlation between the structure-based dissimilarity measures and the sequence-based dissimilarity measures is usually good if the sequence similarity among the homologues is about 30% or more. For protein families with low sequence similarity among the members, the correlation coefficient between the sequence-based and the structure-based dissimilarities are poor.In these cases the structure-based dendrogram clusters proteins with most similar biochemical functional properties better than the sequence-similarity based dendrogram. In multi-domain protein families and disulphide-rich protein families the correlation coefficient for the match of sequence-based and structure-based dissimilarity (SDM) measures can be poor though the sequence identity could be higher than 30%. Hence it is suggested that protein evolution is best modelled using 3-D structures if the sequence similarities (SSM) of the homologues are very low.

Effect of polychlorinated biphenyl, Aroclor 1254 on rat epididymis.

BACKGROUND& OBJECTIVES: Polychlorinated biphenyls (PCB), the synthetic chlorinated organic compounds, are known to decrease thyroid function, sperm count and fertility, and increase the risk of testicular cancer may cause serious effect on male reproduction. The objective of the present study was to study the effect of PCB, Aroclor 1254 on rat epididymal structure and function. METHODS: Adult male albino rats were treated ip with Aroclor 1254, 200 microg/kg body weight for 15 and 30 days. Serum levels of testosterone, estradiol, total triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) were measured by radioimmunoassay. The epididymal weight, sperm count, and caudal epididymal sialic acid, glyceryl phosphoryl choline (GPC) were also investigated. Histological studies were done on caput and caudal epididymal regions. RESULTS: Serum testosterone showed no change, but estradiol levels increased in 30 days treated animals, T3 and T4 levels decreased and TSH levels increased in both 15 and 30 days treated animals. Body weight, epididymal weight, sialic acid, GPC and sperm count were decreased only in 30 days Aroclor treated group. INTERPRETATION & CONCLUSION: The results suggested that Aroclor 1254 treatment for 15 and 30 days induced hypothyroidism in rats, but epididymal functions were altered only at 30 days treatment. The adverse effect of Aroclor 1254 (PCB) on epididymis might be due to indirect action through hormonal regulation.

Effects of prolactin and androgens on enzymes of carbohydrate metabolism in prostate of castrated bonnet monkeys Macaca radiata (Geoffroy).

Effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combinations of these androgens with PRL/Br on the specific activities of caudal and cranial prostatic cellular enzymes involved in carbohydrate metabolism in castrated mature bonnet monkeys have been studied. Castration decreased all the enzymes studied such as hexokinase (HK), 6-phosphofructokinase (6-PFK), glyceraldehyde-3-phosphate dehydrogenase (G-3-PD), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD) and 6-phosphogluconate dehydrogenase (6-PGD) in the cranial and caudal prostates. PRL elevated the activities of all the enzymes above normal except G-3-PD of cranial lobe. In the caudal lobe, PRL brought back the activities of HK, PFK, PK, G-6-PD to normal and 6-PGD above normal except G-3-PD. TP/DHT treatment increased all the enzymes in both the lobes. PRL given along with TP/DHT further enhanced the androgen action with regard to HK, PK, G-6-PD and 6-PGD of cranial and PFK, G-3-PD, PK, G-6-PD and 6-PGD of caudal lobe. Br treatment did not produce any alteration of these enzymes in both the lobes. In the cranial lobe, during Br+TP/DHT treatment, the stimulating effects of androgen were unaffected on all the enzymes except PK. On the other hand in the caudal, the stimulatory effects of androgens were affected and the activities of HK, PFK, PK and 6-PGD were significantly decreased. The present results suggest that PRL has a direct as well as a synergistic action with androgens on enzymes of EMP and HMP shunt in the prostates of monkeys.

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.

Influence of prolactin, androgens and bromocriptine on seminal vesicular and prostatic adenosine triphosphatases in castrated adult monkeys Macaca radiata.

E ects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combinations of these androgens with PRL/Br on specific activities of adenosine triphosphatases (ATPases) of seminal vesicles and cranial and caudal prostates were studied in castrated adult bonnet monkeys. Castration decreased all ATPases (sodium/potassium, magnesium and calcium dependent) of seminal vesicles and both the lobes of prostate. PRL restored the normal activities of all ATPases in both the organs. Br given alone decreased all ATPases of prostate but caused no significant alteration, particularly calcium dependent ATPases of seminal vesicles and caudal prostate. TP/DHT replacement restored all ATPases of both the organs to the normal levels. PRL + TP/DHT further enhanced all the ATPases activities of all the regions studied. Br + TP/DHT decreased all ATPases but it did not produce any alteration in the calcium ATPases of seminal vesicles. The results suggest that prolactin facilitates membrane transport enzymes in the cranial and caudal prostate and seminal vesicles of adult castrated bonnet monkeys.

Effect of corticosterone on epididymal lipids in pubertal rat.

Serum corticosterone excess was induced by the administration of corticosterone acetate to adrenal intact rats. Different lipid classes were studied in unwashed and washed (epididymal sperm and fluid free) caput and cauda epididymides. The unwashed caput epididymidis registered a significant decrease in total lipid, cholesterol and phospholipid while total glyceride glycerol and its fractions were not altered after corticosterone treatment. Among phospholipid fractions phosphatidyl inositol, choline and ethanolamine showed a significant decrease. Unlike the unwashed caput epididymidis, the washed caput region recorded a marked increase in total lipid, glyceride glycerol and its fractions. However, total lipid in the washed cauda region significantly increased and the increase was mainly due to triacyl glycerol. Though the phospholipid fractions phosphatidyl choline and ethanolamine showed an increase, the total phospholipid was not altered significantly. Serum testosterone and prolactin registered a significant decrease while gonadotropins were unaltered. On the withdrawal of corticosterone treatment, all the lipid classes turned to normalcy along with serum testosterone and prolactin. It is concluded that corticosterone excess favours lipid accumulation in the sperm free epididymal tissue and its influence on epididymis is region specific and reversible.

Effects of prolactin and androgens on seminal vesicular lipids of castrated mature bonnet monkeys Macaca radiata.

Effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combination of these androgens with PRL/Br on the total lipid, total cholesterol, total glyceride glycerols, total phospholipid and their fractions in seminal vesicles of castrated mature monkeys were studied. Glyceride glycerols formed the major portion (50%) of total lipids in normal monkeys. Cholesterol and phospholipids were of equal share (25%). Esterified cholesterol formed major share (75%) of total cholesterol. Diacyl glycerol was the major (60%) glyceride glycerol and phosphatidyl choline and ethanolamine were the major phospholipid classes. Except triacyl glycerol castration markedly decreased all the lipid classes. PRL restored normal free and esterified cholesterol and phosphatidyl inositol but Br invariably decreased all the lipid classes. TP/DHT treatment stimulated the free and esterified cholesterol more than the control; it restored the normal glyceride glycerols. Phosphatidyl inositol, choline and ethanolamine were stimulated by androgens and other phospholipid classes were brought to normal. Addition of PRL + TP/DHT markedly increased esterified cholesterol, phosphatidyl inositol, choline, ethanolamine and phosphatidic acid. In all these aspects, Br counteracted the effects of androgens and PRL.

HLA and filariasis in Sri Lankans and Indians.

Similar HLA association was found in patients with elephantiasis in Sri Lankans and Southern Indians. HLA-B15 was observed in 13/44 (30%) Sri Lankan patients with elephantiasis compared to 1/27 (4%) Sri Lankan controls (p = .0058; RR = 10.9) and in 5/8 (28%) Southern Indian elephantiasis compared to 10/101 (10%) Southern Indian controls (p = 0.04; RR = 3.5). In combining the data, the significance of the difference of the frequency of B15 between patients with elephantiasis and controls was even more marked (p = 0.00045; corrected p = 0.012; RR = 4.4).

Influence of sex steroids and prolactin on rat mammary gland.

The effect of sex steroids and prolactin on rat mammary glands. Estradiol-17 beta alone was found to increase the protein concentration significantly. Progesterone increased LDH and G-6-PD activities whereas Estradiol and Prolactin decreased LDH activity. G-6-PD activity was increased by estradiol and prolactin. Glycogen concentration was decreased by prolactin alone. Further, these hormones increased the percentage of total 'M' subunits and decreased total 'H' subunits of LDH. In general, sex steroids and prolactin increased glycogen utilisation and prepared the Mammary Gland or anaerobic metabolism.

Hormonal influences on the oviducal lactate dehydrogenase and its isoenzymes.

Changes in the specific activities and distribution of lactate dehydrogenase (LDH) isoenzymes have been studied in the oviduct of intact, ovariectomized and ovariectomized-hormone treated rats. Total LDH and M-subunits were higher in the oviduct during estrus compared to early diestrus phase. Ovariectomy lowered the total activity as well as the proportion of H and M-subunits of LDH, with a total loss of LDH. Treatment of ovariectomized rats with progesterone (2 mg/100 g. body wt/rat/day) and estradiol-17 beta (0.5 microgram/100 g body wt/rat/day) for 7 consecutive days induced marked augmentations in the total activities of this oviducal enzyme. Further, there was a shift in the isoenzyme patterns towards M-type, especially LDH5. Prolactin (400 microgram/100 g body wt/rat/day) depressed the total LDH activity and the distribution of isoenzymes. While LDH4 and LDH5 were very low, LDH1--LDH3, were inclusive, were absent in the oviduct of prolactin-treated group. None of the hormonal replacements could stimulate the LDH4 - subunit. The significance of these changes has been discussed in relation to metabolic activities in the tissue and hormonal influences.