Morphometric and Histological Study of Breast Lesions with Special Reference to Proliferative Activity and Invasiveness

Breast carcinoma is the most common cause of carcinoma death in women. Sometimes, difficulty arises to differentiate between premalignant lesions and carcinoma by routine histopathology. Our study was done to establish the role of morphometry and immunohistochemistry to solve this problem. In this study, total 60 cases of different breast lesions were included and 10 controls were also included to compare the results with the normal findings. They were studied by hematoxylin and eosin-stained sections for morphometry and routine histological study; as well as by proliferative markers such as proliferating cell nuclear antigen and p53. Invasiveness was studied using immunohistochemical staining with 34 βE12 monoclonal antibody. Statistically significant differences were found in morphometric parameters and in expression of proliferative markers between most of them. Morphometry and immunohistochemistry help in the proper diagnosis of different breast lesions that lie in the gray zone on routine histopathology.     

Detection and isolation of exotic Newcastle disease virus from field-collected flies

Flies were collected by sweep net from the vicinity of two small groups of "backyard" poultry (10-20 chickens per group) that had been identified as infected with exotic Newcastle disease virus (family Paramyxoviridae, genus avulavirus, ENDV) in Los Angeles County, CA, during the 2002-2003 END outbreak. Collected flies were subdivided into pools and homogenized in brain-heart infusion broth with antibiotics. The separated supernatant was tested for the presence of ENDV by inoculation into embryonated chicken eggs. Exotic Newcastle disease virus was isolated from pools of Phaenicia cuprina (Wiedemann), Fannia canicularis (L.), and Musca domestica L., and it was identified by hemagglutination inhibition with Newcastle disease virus antiserum. Viral concentration in positive pools was low (<1 egg infectious dose50 per fly). Isolated virus demonstrated identical monoclonal antibody binding profiles as well as 99% sequence homology in the 635-bp fusion gene sequence compared with ENDV recovered from infected commercial egg layer poultry during the 2002 outbreak.     

Binding of Escherichia coli heat-stable toxin and rise of guanylyl cyclase activity in the brush-border membranes of rabbit intestinal epithelial cells

The study examines the age-related differences in the density of Escherichia coli heat-stable enterotoxin (STa) receptors in the small intestine of rabbits. The number of STa receptors was found to be 1.7 x 10(12) in 14-day old rabbits compared to 2.4 x 10(9) in 14-week old rabbits per milligram brush-border membrane protein. The STa-induced guanylyl cyclase activity in the intestinal brush-border membranes was found to be stimulated by 6.2 folds over the basal enzyme activity in 14-day old rabbits, whereas in the 14-week old rabbits, it was 4 folds over the basal activity. Moreover, the enzyme activity remained lower in the adult rabbits compared to the younger ones. Autoradiographic analysis of sodium dodecyl sulphate polyacrylamide gel electrophoresis showed two STa-binding proteins of apparent molecular weights of 140 and 38 kDa in the intestinal brush-border membranes of rabbits.     

Gene sequence tags from Plasmodium falciparum genomic DNA fragments prepared by the "genease" activity of mung bean nuclease.

A genes-first approach to genome sequencing is described which efficiently generates gene sequence tags from genomic DNA. Mung bean nuclease (EC 3.1.30.1) cleaves the genomic DNA of many organisms before and after genes and within some introns. Analysis of gene sequence tags prepared from mung bean nuclease-digested Plasmodium falciparum DNA demonstrates that this method has several advantages over the popular cDNA expressed sequence tag approach. To date, 673 sequence tags containing over 215 kb of sequence have been generated from 400 clones. Sixty clones (15%) have significant similarity to sequences in the protein and translated nucleic acid data bases. These represent 51 unique genes, of which only 5 encode previously known P. falciparum proteins. The identified proteins include those expressed in erythrocytic, exoerythrocytic, and gametocytic stages of the parasite. Thirty percent of clones identified appear to carry complete coding regions. The spacer DNA separating genes is rarely cloned. These gene sequence tags will form a useful data base from which to initiate projects to develop new therapeutics, vaccines, and strategies to control human malaria.     

Endothelin-mediated remodeling in aortas of diabetic rats

BACKGROUND: Smooth muscle cells proliferation and extracellular matrix (ECM) protein deposition are key features of diabetic macroangiopathy. In the present study, we have studied the role of endothelin(A) (ET(A)) receptor, the predominant receptor on smooth muscle cells, in diabetes-induced vascular hypertrophy and remodeling. METHODS: Streptozotocin-induced diabetic rats were administrated a selective ET(A) receptor antagonist, TBC3214, for 26 weeks. Following treatment, aortas were harvested and subjected to gene expression and morphometric analyses. We quantified fibronectin (FN) and plasminogen activator inhibitor-1 (PAI-1) expression as indicators of increased ECM protein synthesis. ET-1, ET-3, transforming growth factor-beta1 (TGF-beta1) and angiotensinogen mRNA levels were measured to elucidate genes involved in FN expression. We have investigated an embryonic splice variant of FN, oncofetal FN, and nonmuscle myosin heavy chain (SMemb) as vascular remodeling indicators. RESULTS: Our results show that diabetes leads to upregulation of FN, PAI-1, ET-1, ET-3, TGF-beta1 and angiotensinogen mRNA levels in association with increased medial thickness. Immunohistochemical analyses revealed concurrent protein level changes. Diabetes also upregulated oncofetal FN and SMemb mRNA levels. Treatment with TBC3214 attenuated the mRNA levels of several genes and prevented increased medial thickness. CONCLUSIONS: These results indicate that diabetes-induced vascular hypertrophy and remodeling is associated with reexpression of embryonic forms of FN and myosin heavy chain. Such changes are ET-dependent and may be mediated via TGF-beta1 and angiotensin.