Genetic polymorphism of the glutathione-S-transferase P1 gene (GSTP1) and susceptibility to prostate cancer in the Kashmiri population

Glutathione-S-transferase P1 (GSTP1) is a critical enzyme of the phase II detoxification pathway. One of the common functional polymorphisms of GSTP1 is A→G at nucleotide 313, which results in an amino acid substitution (Ile105Val) at the substrate binding site of GSTP1 and reduces catalytic activity of GSTP1. To investigate the GSTP1 Ile105Val genotype frequency in prostate cancer cases in the Kashmiri population, we designed a case-control study, in which 50 prostate cancer cases and 45 benign prostate hyperplasia cases were studied for GSTP1 Ile105Val polymorphism, compared to 80 controls taken from the general population, employing the PCR-RFLP technique. We found the frequency of the three different genotypes of GSTP1 Ile105Val in our ethnic Kashmir population, i.e., Ile/Ile, Ile/Val and Val/Val, to be 52.4, 33.3 and 14.3% among prostate cancer cases, 48.5, 37.5 and 14% among benign prostate hyperplasia cases and 73.8, 21.3 and 5% in the control population, respectively. There was a significant association between the GSTP1 Ile/Val genotype and the advanced age group among the cases. We conclude that GSTP1 Ile/Val polymorphism is involved in the risk of prostate cancer development in our population.

Risk of colorectal cancer associated with the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in the Kashmiri population

Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA synthesis, DNA repair and DNA methylation. The two common functional polymorphisms of MTHFR, 677 C→T and 1298 A→C, have been shown to impact various diseases, including cancer. The 677 C→T polymorphism has been widely investigated in different cancers and has been implicated as a risk factor for the development of various cancers. We investigated MTHFR C677T genotype frequency in colorectal cancer cases in the Kashmiri population and correlated this information with the known clinicopathological characters of colorectal cancer, in a case-control study. Eighty-six colorectal cancer cases were studied for MTHFR C677T polymorphism, compared to 160 controls taken from the general population, employing the PCR-RFLP technique. We found the frequency of the three different genotypes of MTHFR in our ethnic Kashmir population, i.e., CC, CT and TT, to be 68.6, 20.9 and 10.4% among colorectal cancer cases and 75.6, 16.9 and 7.5% among the general control population, respectively. There was a significant association between the MTHFR TT genotype and colorectal cancer in the higher age group. We conclude that the MTHFR C677T polymorphism slightly increases the risk for colorectal cancer development in our ethnic Kashmir population.

TP53 Pro47Ser and Arg72Pro polymorphisms and colorectal cancer predisposition in an ethnic Kashmiri population

Two TP53 gene polymorphisms at codon 47 (TP53 Pro47Ser) and at codon 72 (TP53 Arg72Pro) have been associated with susceptibility to various cancers. We carried out a case-control study and examined the genotype distribution of TP53 Pro47Ser and Arg72Pro single nucleotide polymorphisms (SNPs), using a PCR-RFLP approach, to determine if these two SNPs are risk factors for colorectal cancer (CRC) development and to look for a possible correlation of these two SNPs with clinicopathological variables of CRC. We investigated the genotype distribution of these SNPs in 86 CRC cases in comparison with 160 healthy subjects in an ethnic Kashmiri population. TP53 Arg72Pro SNP genotype frequencies differed significantly (P = 0.000001) between the groups; the frequency of the Pro/Pro mutant was almost 20% in the general population. We also found significant association of the Pro/Pro mutant with tumor location, nodal status/higher tumor grade and bleeding per rectum/constipation. We conclude that Arg72Pro SNP is associated with susceptibility to developing CRC in this ethnic Kashmiri population.

Effect of amlodipine and lisinopril on microalbuminuria in patients with essential hypertension: A prospective study

Microalbuminuria can be present in 25-100% of patients with essential hypertension and is associated with increased incidence of cardiovascular events. Our goal was to evaluate the effect of a commonly used calcium channel blocker, amlodipine, and an angiotensin converting enzyme inhibitor, lisinopril on urinary albumin excretion in patients with mild to moderate essential hypertension. We screened 324 patients with essential hypertension for microalbuminuria and documented it in 120 patients. These 120 patients with microalbuminuria were randomly divided into two groups of 60 each, matched for age, sex, arterial pressure, creatinine clearance, and urinary albumin excretion so as to receive amlodipine or lisinopril. We prospectively measured their urinary albumin excretion and creatinine clearance prior to treatment and, four and eight weeks after treatment with amlodipine or lisinopril. Mean arterial pressure (mean +/- SD) at baseline, after four weeks, and after eight weeks was 113.01 +/- 4.38,104.93 +/- 3.12, and 98.89 +/- 1.75 mmHg (P < 0.0000); and 114.13 +/- 7.11, 106.52 +/- 3.50, and 100.89 +/- 2.80 mmHg (P < 0.0000) in amlodipine and lisinopril groups, respectively. Urinary albumin excretion (mean +/- SEM) at baseline, after four, and after eight weeks was 79.30 +/- 3.74, 62.03 +/- 3.61, and 52.02 +/- 3.05 (P < 0.0000); and 73.96 +/- 4.10, 72.39 +/- 3.74, 66.12 +/- 3.94 (P = 0.1742) in lisinopril and amlodipine groups, respectively. Lisinopril but not amlodipine, reduced the urinary albumin excretion significantly despite their similar antihypertensive efficacy. The clinical and prognostic significance of these observations need to be established.

Use of a night vision intensifier for direct visualization by eye of far-red and near-infrared fluorescence through an optical microscope

We describe the design, construction and testing of a prototype device that allows the direct visualization by eye of far-red and near-infrared (NIR) fluorescence through an optical microscope. The device incorporates a gallium arsenide (GaAs) image intensifier, typically utilized in low-light or 'night vision' applications. The intensifier converts far-red and NIR light into electrons and then into green light, which is visible to the human eye. The prototype makes possible the direct, real-time viewing by eye of normally invisible far-red and NIR fluorescence from a wide variety of fluorophores, using the full field of view of the microscope to which it is applied. The high sensitivity of the image intensifier facilitates the viewing of a wide variety of photosensitive specimens, including live cells and embryos, at vastly reduced illumination levels in both fluorescence and bright-field microscopy. Modifications to the microscope are not required in order to use the prototype, which is fully compatible with all current fluorescence techniques. Refined versions of the prototype device will have broad research and clinical applications.

Coreceptor function of mutant human CD4 molecules without affinity to gp120 of human immunodeficiency virus

Despite extensive mutational studies on the human CD4 molecule and its affinity to human immunodeficiency virus (HIV) envelope glycoprotein gp120, coreceptor functions of such mutant molecules have only been examined by indirect measurement of their affinity to class II major histocompatibility complex (MHC) molecules. In this report, coreceptor functions of mutant human CD4 molecules, which have no or reduced affinity to an HIV envelope protein, gp120, were assessed in a murine T cell receptor/class II MHC recognition system. The substitution of human C" beta strand with the murine homologous segment resulted in the loss of the coreceptor function as well as in the complete loss of gp120 binding capacity, corroborating the consensus that Phe-43 in C" beta strand plays crucial roles in both situations. However, simultaneous replacement of the C'-C" loop along with the C" beta strand by homologous murine segments rescued the coreceptor function, whereas gp120 binding capacity remained negative. Further analysis indicated that insertion of lysine between Gly-41 and Ser-42 can partially compensate for the coreceptor function lost by the Phe-43 --> Val mutation. Although the coreceptor function of these mutant CD4 molecules in a human T cell recognition system is yet to be determined, these observations necessitate a re-evaluation of the role played by Phe-43 in coreceptor function. Examination of the sensitivities of the mutant CD4 molecules expressed on HeLa cells to infection by a T cell-tropic HIV-1 strain indicated that only those mutants that had completely lost gp120 binding capacity were resistant to the infection. All mutants having whole C" substitution, irrespective of additional substitutions or their coreceptor functions, were resistant to the infection.

Differential regulation of activation-induced cell death in individual human T cell clones

BACKGROUND

Restimulation of T lymphocytes via the TCR/CD3 complex can result in CD95/CD95L-dependent activation-induced cell death (AICD). Although the correlation of AICD sensitivity to the T helper 1 phenotype was confirmed in different studies, the underlying mechanism is still debated. Thus, it has been suggested that in Th2 cells, AICD resistance is controlled by a TCR-induced upregulation of the CD95-associated inhibitory phosphatase, FAP-1. We and others demonstrated that AICD resistance is associated with a reduced surface expression of CD95L upon restimulation.

METHODS

Utilizing RT-PCR, Western blotting and flow cytometry, we analyzed time-dependent changes in levels of CD95L mRNA, cytosolic protein and surface expression in five long-term human T cell clones and polarized helper populations.

RESULTS

We confirm that the inducible CD95L surface expression is lower or absent in all tested AICD-resistant clones as compared to sensitive cells. It is of interest that striking differences with respect to the activation-dependent inducibility of CD95L mRNA expression in individual resistant clones were observed. In addition, alterations in the expression of the inhibitory phosphatase FAP-1 or TCR-dependent changes in CD95 sensitivity in AICD-resistant clones could be ruled out as a mechanism for AICD resistance of human T cell clones.

CONCLUSIONS

(1) The data presented strongly support the previous notion that AICD resistance of human T cell clones is mainly regulated by a differential expression of CD95L. (2) Differential expression of CD95L on individual resistant clones results from a lack of mRNA induction in one set and from a markedly decreased surface expression of translated protein in another set of clones.

Comparative analysis of the gp120-binding area of murine and human CD4 molecules

The structural basis for the difference between human and murine CD4 molecules in binding to HIV envelope protein gp120 has been intensively studied. Eighteen mutant human CD4 molecules were produced by segmental replacement of beta strands and loops in the gp120-binding area of the molecule with corresponding murine sequences or by single amino acid substitutions. Examination of these mutant CD4 molecules for gp120 binding indicated that murine CD4 molecule does not bind gp120 for the following three reasons: (a) The loops flanking the C" strand are longer than their human counterparts, causing significant difference in local tertiary structure; (b) valin, rather than phenylalanine, which is the key amino acid for the binding occupies position 43; (c) amino acids at positions 45 and 46 are different, causing further decrease in binding affinity. Furthermore, the present study indicated that the aromatic ring of Phe43 and the negative charge of Arg59 play key roles in gp120 binding.

Carcinoembryonic antigen directed multiple surgical procedures for recurrent colon cancer confined to the liver

During the past 14 years, eight patients have undergone two or more major hepatic procedures in an attempt to control metastatic colon cancer confined to the liver. A total of 19 operations was performed. In all cases, a rising level of carcinoembryonic antigen was the main indicator for surgical intervention. There were no operative deaths. Major complications occurred in 15 per cent. Following the first hepatic intervention, two patients remain alive and free of disease at 43 and 47 months (56 and 100 months since diagnosis), respectively. In the six patients who have died, survival from the first hepatic intervention ranged from 17 to 38 months (median 27 months). Age, sex, location of primary, size of primary, interval from primary operation to second operation, and site of hepatic metastasis did not influence survival. In carefully selected patients with metastatic colon carcinoma confined to the liver, encouraging results can be obtained by performing multiple surgical procedures.

Pre-operative and post-operative evaluation of circulating immune complexes in patients with gastric adenocarcinoma

Circulating immune complexes (CICs) in the sera of patients with histologically proven adenocarcinoma of stomach were sequentially studied. Serial CICs levels, quantitated using a sensitive method F(ab')2 anti-C3 ELISA, were measured before surgery and in a post-operative follow up. CICs could be detected in 85% of the patients pre-operatively, while ten days after surgery positivity decreased to 71%. Thirty days after surgery, the mean CIC levels decreased significantly and positivity fell to 46%. The results indicate that removal of primary tumor mass results in a sharp decline of CIC levels.

Localization by hand-held gamma probe of tumor labeled with antibody "cocktail"

Five groups (n = 4) of congenitally athymic female nude mice bearing subcutaneous implants of CX-1 and/or SW-1116 tumor in the hind limbs received iodine-125 radio-labeled monoclonal antibodies (MoAbs) B72.3 (two groups), 17-1A (two groups), and cocktail (one group) (iodogen method, 50 microCi/10 micrograms/mouse). Daily probe counts were made in duplicate with a hand-held detector over each tumor site and the front leg (background) for 21 days. Animals were sacrificed and appropriate well counts were obtained. All the single MoAb preparations localized well in both tumor cell lines. Uptake of monoclonal antibody 17-1A was similar in the two tumor cell lines, with counts initially high and slowly decreasing over the 21-day period. Tumor/background ratios continued to increase over time, indicating that both tumor lines have similar antigenic expression for the monoclonal antibody 17-1A. This was not the case for monoclonal antibody B72.3, which showed a preferential uptake by the CX-1 tumor, with higher initial counts and prolonged binding of the antibody, giving rise to higher tumor/background ratios. The mixture of monoclonal antibodies B72.3 and 17-1A markedly improved the uptake by the CX-1 tumor cell line but not that by the SW-1116 cell line, where the effect was negative when compared to the uptake of the single MoAb preparations. The use of a monoclonal antibody mixture can enhance targeting of some tumor sites. Due to the heterogeneity of tumor cell lines, even within the same animal, different mixtures of monoclonal antibodies are needed to increase the targeting of tumor.

Staging of carcinoma of the breast using a hand-held gamma detecting probe and monoclonal antibody B72.3

Radioimmunoguided Surgery (RIGS) uses a hand-held gamma detecting probe to identify radiolabeled monoclonal antibodies (Mab). Fourteen patients with carcinoma of the breast proved at biopsy received Mab B72.3 (5 millicuries of 125I per 1 milligram, Iodo-Gen method) intravenously six to 26 days before exploration. Probe counts were measured intraoperatively in mammary tissue and axillary lymph nodes. In the mammary tissue, the RIGS system identified tumor that was histologically confirmed in seven of eight patients and confirmed the absence in four of six patients. Probe counts were suspicious for tumor that was not proved histologically in two of 14 patients. Unsuspected tumor was identified in three of 14 patients. In axillary tissue, probe counts identified one of two tumors that were confirmed histologically and verified the absence of tumor in eight of 12 patients. Probe counts in axillary tissue were suspicious for tumor that could not be documented histologically in four of 14 patients. RIGS appears to be able to identify residual, subclinical and multicentric carcinoma of the breast and accurately delineate the pattern of antigenic drainage of tumor into adjacent lymph nodes.

An assessment of prolonged reactivity of seven monoclonal antibodies against CX-1 tumor xenografts using a hand-held gamma-detecting probe

The biodistribution and kinetics of 7 monoclonal antibodies (MAb) with known reactivity against CX-1 tumor were examined over 21 days using a hand-held gamma-detecting probe (Neoprobe system). Twenty-eight immuno-deprived (athymic) nude mice implanted with human colon adenocarcinoma CX-1 xenografts were injected intraperitoneally with 50 microCi of 125I-labeled antibodies (4 mice/antibody). Of the 7 monoclonal antibodies, 4 were anti-CEA (MA, MB, MC, and MD), 2 were anti-TAG 72 (B72.3 NCI and B72.3 fermented) and one was anti-colorectal cancer (17-1A). Daily probe counts were recorded in duplicate over the tumor site and the contralateral nontumor site (background), and tumor-to-background (Tu/Bkg) ratios were calculated. Animals were sacrificed on day 21, and blood, heart, liver, spleen, lungs, kidneys, intestine, muscle, and the tumor were removed for gamma well counting. All antibodies identified the tumor as early as 24 h postinjection and specific tumor localization improved over time. Patterns of prolonged tumor binding varied considerably from one antibody to another, although all but one (MB) showed continuously increasing Tu/Bkg ratios. These data indicate progressive clearance of the antibodies from the background tissue and a persistence of labeled MAb activity in tumor resulting in improved tumor localization with increasing postinjection time.

Selective IgG subclass antibody response to insulin in diabetic patients receiving animal insulin replacement therapy

Serum IgG subclass antibodies to insulin were semiquantitatively estimated using a highly sensitive and specific technique of enzyme-linked immunosorbent assay. The three groups of patients (categorised on the basis of duration and dose of exogenous insulin administered) showed a variable pattern. In spite of considerable variations from patient to patient in a group, IgG1 and IgG2 levels were higher in patients receiving a low dose of insulin for 9-18 and 30-72 months, respectively, while in the patients on high dose of therapeutic insulin, IgG4 well predominated over all other subclasses. It is postulated that IgG4 antibodies are directed against the biologically active site of insulin and explains the high requirement of insulin in these patients.

An 'antigen capture' ELISA for secretory immunoglobulin A antibodies to hepatitis B surface antigen in human saliva

An enzyme-linked immunosorbent assay (ELISA) was developed which permits the assay of specific secretory immunoglobulin A (sIgA) antibodies against hepatitis B surface antigen (HBsAg) in saliva. The assay is based on the binding of sIgA antibodies present in saliva to microtitre plates coated with excess of F(ab')2 anti-secretory component antibodies, followed by the addition of specific antigen, HBsAg and finally peroxidase-labelled anti-HBsAg. The assay is fast, simple, reproducible and antigen specific as shown by total absence of inhibition of specific antigen by unrelated antigens but significant inhibition of labelled anti-HBsAg by unlabelled anti-HBsAg. The values obtained for hospital personnel exposed to hepatitis infections (0.068 +/- 0.083 U/ml) and for post-icteric hepatitis B patients (0.062 +/- 0.033 U/ml) were significantly higher than values in control subjects (0.013 +/- 0.006 U/ml).

Radioimmunoguided surgery using monoclonal antibody

The potential proficiency of radioimmunoguided surgery in the intraoperative detection of tumors was assessed using labeled monoclonal antibody B72.3 in 66 patients with tissue-proved tumor. Monoclonal antibody B72.3 was injected 5 to 42 days preoperatively, and the hand-held gamma-detecting probe was used intraoperatively to detect the presence of tumor. Intraoperative probe counts of less than 20 every 2 seconds, or tumor-to-adjacent normal tissue ratios less than 2:1 were considered negative (system failure). Positive probe counts were detected in 5 of 6 patients with primary colon cancer (83 percent), in 31 of 39 patients with recurrent colon cancer (79 percent), in 4 of 5 patients with gastric cancer (80 percent), in 3 of 8 patients with breast cancer (37.5 percent), and in 4 of 8 patients with ovarian cancer (50 percent) undergoing second-look procedures. Additional patients in each group were scored as borderline positive. Overall, radioimmunoguided surgery using B72.3 identified tumors in 47 patients (71.2 percent), bordered on positive in 6 patients (9.1 percent), and failed to identify tumor in 13 patients (19.7 percent). Improved selection of patients for antigen-positive tumors, the use of higher affinity second-generation antibodies, alternate routes of antibody administration, alternate radionuclides, and more sophisticatedly bioengineered antibodies and antibody combinations should all lead to improvements in radioimmunoguided surgery.

Single- and double-strand break formation in DNA irradiated in aqueous solution: dependence on dose and OH radical scavenger concentration

The yields of single- and double-strand breaks (SSB and DSB) in calf thymus DNA, after 60Co gamma irradiation in dilute aqueous solution, have been determined via molecular weight measurements using a low-angle laser light scattering technique. The irradiations were administered to N2O-containing solutions of DNA in the absence and presence of oxygen and with different concentrations of the OH radical scavengers phenol, tertiary butanol, and methanol. OH radicals were found to produce SSB linearly with dose with a G value of 55 nmol J-1 and 54 nmol J-1 in deoxygenated and oxygenated solutions, respectively. DSB were formed according to a linear-quadratic dose relationship and the G value of linearly formed DSB were GDSB alpha(r.t.) = 3.5 nmol J-1 in deoxygenated and 3.2 nmol J-1 in oxygenated solution. The ratio of GSSB/GDSB alpha(r.t.) = gamma of 19 +/- 6 was independent of the scavenger concentration in the case of tertiary butanol and methanol-containing solutions. GDSB alpha(r.t.) is interpreted to result from a radical site transferred from a sugar moiety of the cleaved strand to the complementary intact strand. This process of radical transfer and subsequent cleavage of the second strand occurs with a probability of about 6 +/- 2% in the presence of oxygen at all scavenger concentrations studied. These data on scavenging capacity on GDSB alpha(r.t.) suggest that the double-strand breakage produced via radical transfer remains higher than that resulting from direct effect, up to scavenging capacities of about 10(9) s-1.

Bacterial metabolism of mevalonic acid

Soluble cell-free extracts of actinomycete S4 grown on media containing mevalonate catalyze acetoacetate formation from mevalonate, mevaldate, and beta-hydroxy-beta-methylglutaryl-coenzyme A (CoA). Conversion of mevalonate to acetoacetate involves formation of free beta-hydroxy-beta-methylglutaryl-CoA, but not free mevaldate. The reaction favors mevalonate oxidation, and nicotinamide adenine dinucleotide, rather than nicotinamide adenine dinucleotide phosphate, acts as oxidant.

The Development of the Penile Urethra and the Homology of Cowper's Gland of Male Spermophile (Citellus Tridecemlineatus) with a note on the Prostatic Utricle

Images

Breech Fused Twin Monster

Images

Variations in the Lower End of Femur from Indians

Images