Cell membrane-associated MT1-MMP-dependent activation of pro-MMP-2 in A375 melanoma cells.

Matrix metalloproteinases (MMPs), a family of zinc-dependent endopeptidases, can degrade extracellular matrix components under physiological conditions and during cancer invasion and metastasis. Among the MMPs, the 72 kDa type IV collagenase MMP-2 (gelatinase A) is activated in a membrane-associated manner by an activation complex composed of membrane type 1 matrix metalloproteinase (MT1-MMP), tissue inhibitor of matrixmetalloproteinase-2 (TIMP-2), and pro-MMP-2 in the presence of alphavbeta3 integrin receptor. The activation of pro-MMP-2 correlates with increased occurrence of metastases. Increased MMP-2 activity has been demonstrated in many human tumors. In the present communication, we studied cell surface-associated activation of MMP-2 (72 kDa collagenase type IV) in the moderately metastatic human melanoma cell line A375. RESULTS: Activation of purified 72 kDa collagenase type IV, pro-MMP-2 from cervical cancer tissue homogenate and from serum-free culture medium of HT1080 cells grown in presence of concanavalin A, by A375 cells, was shown by gelatin zymography. A375 cells activated only pro-MMP-2 from purified MMP-9/MMP-2 mixture indicating that the activation is specific for MMP-2. Activation of MMP-2 and purified collagenase type IV by A375 membrane fraction and membrane extract was also demonstrated by gelatin zymography. When A375 cells were first incubated with anti-MT1-MMP polyclonal antibody, activation of collagenase type IV was significantly decreased, indicating that membrane-associated MMP-2 activation is MT1-MMP-mediated. Immunocytochemistry showed MT1-MMP localization at focal adhesion sites. The presence of the components of activation complex-MT1-MMP and integrin alphavbeta3-were confirmed by Western blot, cell adhesion assay, and integrin subunit assay. CONCLUSION: Our experimental findings furnish another example of the unique membrane-associated MMP-2 activation mechanism in A375 melanoma cells and clearly indicate the role of MT1-MMP in MMP-2 activation. The information could help in developing new therapies designed to interfere with MMP activation and management of cancer and metastases.     

Role of a second stage partogram in predicting the outcome of normal labour

Background: Management of the second stage of labour is dictated by arbitrary time limits rather than true measures of progress. No partogram is available for second stage of labour.
Objectives: To evaluate a partogram designed for use for the second stage of labour.
Methods: This prospective cross-sectional analytical study included low-risk pregnant women with singleton fetuses with vertex presentations at term. From onset of the second stage, vaginal examinations were performed every 30 min until delivery. A scoring system developed by Sizer et al . was used based on station and position of fetal head. Scores were plotted on a second stage partogram and used to predict labour outcomes, such as duration of second stage and mode of delivery.
Results: Of 79 women examined, 73 had spontaneous vaginal delivery. Of the remaining six, four required oxytocin infusion and other two required vacuum extraction. The median durations of the second stage of labour for primigravidas ( n  = 34) and multigravidas ( n  = 45) were 35 and 25 min, respectively. The median Sizer's partogram score at the onset of second stage was 4. Multiple regression analysis showed that the partogram score ( r ² = 0.27) and gravidity ( r ² = 0.10) were independent predictors of duration of the second stage. There was a significant association between second stage progress plotted to the right of the partogram line and non-spontaneous delivery ( P =  0.01).
Conclusion: The second stage partogram score at onset can predict the duration of second stage. Poor progress plotted on the partogram is associated with non-spontaneous delivery.     

Primary breast sarcomas--report of two cases

Two (2) primary breast sarcomas out of 110 primary breast malignancies from N.R.S. Medical College, Kolkata are being reported. Primary Breast Sarcomas are classified into five (5) broad groups with their representative features. Our two cases are classified as fibrosarcoma and malignant haemangioendothelioma and their features are documented. Because of its rarity, we are presenting this case with brief review of literature.     

Can homeopathic arsenic remedy combat arsenic poisoning in humans exposed to groundwater arsenic contamination?: a preliminary report on first human trial

Groundwater arsenic (As) has affected millions of people globally distributed over 20 countries. In parts of West Bengal (India) and Bangladesh alone, over 100 million people are at risk, but supply of As-free water is grossly inadequate. Attempts to remove As by using orthodox medicines have mostly been unsuccessful. A potentized homeopathic remedy, Arsenicum Album-30, was administered to a group of As affected people and thereafter the As contents in their urine and blood were periodically determined. The activities of various toxicity marker enzymes and compounds in the blood, namely aspartate amino transferase, alanine amino transferase, acid phosphatase, alkaline phosphatase, lipid peroxidation and reduced glutathione, were also periodically monitored up to 3 months. The results are highly encouraging and suggest that the drug can alleviate As poisoning in humans.     

Vulnerability to HIV/AIDS among women of reproductive age in the slums of Delhi and Hyderabad,India

This report explores how vulnerability to HIV/AIDS applies to women in the reproductive age range living in the slum areas of Delhi and Hyderabad. The paper is based on a qualitative study of AIDS awareness levels conducted during the summer of 2006. It offers insightful narratives from a sample of 32 women, providing an in depth view of their vulnerability to HIV/AIDS due to their precarious socioeconomic conditions and low AIDS awareness. The women cited lack of education, low empowerment in expressing and accessing information related to sexual matters, and poverty as key factors to vulnerability.     

ANALYSIS OF O-H…O HYDROGEN BONDS*

Some geometrical parameters associated with the donor and the acceptor end of O-H…O hydrogen bonds have been analysed. The data consist of 356 hydrogen bonds from reported crystal structures of amino acids, peptides and oligosaccharides. The following conclusions are arrived at: (a) The most probable range for the hydrogen bond length is between 2.7–2.8 å, the average being 2.76 å. When the donor is a water molecule the distribution is slightly different from the other cases. The average becomes 2.82 å, indicating that O-H…O hydrogen bonds, where a water molecule acts as a donor, tend to be slightly larger. (b) The maximum in the distribution for the hydrogen bond angle (H-O‥ .O) lies in the range 5°–10°, indicating that the O-H…O hydrogen bonds tend to be slightly nonlinear, a feature similar to that for N-H…O hydrogen bonds. (c) For carbonyl type of acceptor groups, the distribution of angle between O‥ .O (or H…O) and C = O extended shows a maximum in the range 50°–60° indicating a directional property towards the lone pair electrons. In order to study the effect of lone pair orbitals on the direction of orientation of the O-H group the following parameters connected with the direction of lone pair orbitals are analysed and the main results are: (d) The elevation of O‥ .O (and H…O) direction from the acceptor plane (plane containing the lone pair orbitals), (ζ), shows a maximum in the range O°–10° indicating that the direction thus tends to lie close to the acceptor plane. For carbonyl acceptor groups, the distribution is uniform up to 30° and many of the larger values of ζ are found to occur for carbonyl acceptor groups only. (e) The distribution for the angle between the projection O_accep.…O_donor (and O_accep.…H) direction on the acceptor plane and the direction of the lone pair orbital (ζ) shows a maximum in the range O°–30°. The distribution is found to be dependent on the number of hydrogen bonds for which the same oxygen atom is the acceptor. The distribution for ζ shows a maximum between 20°–30° for those cases when the oxygen atom is recipient of only one hydrogen bond and the maximum occurs between O°–10° for those cases when the oxygen receives two hydrogen bonds. (f) The geometry in the limited number of examples where the oxygen is the recipient of three hydrogen bonds is also discussed.     

Systematic evaluation of variability in ChIP-chip experiments using predefined DNA targets

The most widely used method for detecting genome-wide protein-DNA interactions is chromatin immunoprecipitation on tiling microarrays, commonly known as ChIP-chip. Here, we conducted the first objective analysis of tiling array platforms, amplification procedures, and signal detection algorithms in a simulated ChIP-chip experiment. Mixtures of human genomic DNA and "spike-ins" comprised of nearly 100 human sequences at various concentrations were hybridized to four tiling array platforms by eight independent groups. Blind to the number of spike-ins, their locations, and the range of concentrations, each group made predictions of the spike-in locations. We found that microarray platform choice is not the primary determinant of overall performance. In fact, variation in performance between labs, protocols, and algorithms within the same array platform was greater than the variation in performance between array platforms. However, each array platform had unique performance characteristics that varied with tiling resolution and the number of replicates, which have implications for cost versus detection power. Long oligonucleotide arrays were slightly more sensitive at detecting very low enrichment. On all platforms, simple sequence repeats and genome redundancy tended to result in false positives. LM-PCR and WGA, the most popular sample amplification techniques, reproduced relative enrichment levels with high fidelity. Performance among signal detection algorithms was heavily dependent on array platform. The spike-in DNA samples and the data presented here provide a stable benchmark against which future ChIP platforms, protocol improvements, and analysis methods can be evaluated.     

Copy number variant analysis of human embryonic stem cells

Differences between individual DNA sequences provide the basis for human genetic variability. Forms of genetic variation include single-nucleotide polymorphisms, insertions/duplications, deletions, and inversions/translocations. The genome of human embryonic stem cells (hESCs) has been characterized mainly by karyotyping and comparative genomic hybridization (CGH), techniques whose relatively low resolution at 2-10 megabases (Mb) cannot accurately determine most copy number variability, which is estimated to involve 10%-20% of the genome. In this brief technical study, we examined HSF1 and HSF6 hESCs using array-comparative genomic hybridization (aCGH) to determine copy number variants (CNVs) as a higher-resolution method for characterizing hESCs. Our approach used five samples for each hESC line and showed four consistent CNVs for HSF1 and five consistent CNVs for HSF6. These consistent CNVs included amplifications and deletions that ranged in size from 20 kilobases to 1.48 megabases, involved seven different chromosomes, were both shared and unique between hESCs, and were maintained during neuronal stem/progenitor cell differentiation or drug selection. Thirty HSF1 and 40 HSF6 less consistently scored but still highly significant candidate CNVs were also identified. Overall, aCGH provides a promising approach for uniquely identifying hESCs and their derivatives and highlights a potential genomic source for distinct differentiation and functional potentials that lower-resolution karyotype and CGH techniques could miss. Disclosure of potential conflicts of interest is found at the end of this article.