A novel interaction between the FLJ33534 locus and smoking in obesity: a genome-wide study of 14 131 Pakistani adults.

BACKGROUND: Obesity is a complex disease caused by the interplay of genetic and lifestyle factors, but identification of gene-lifestyle interactions in obesity has remained challenging. Few large-scale studies have reported use of genome-wide approaches to investigate gene-lifestyle interactions in obesity. METHODS: In the Pakistan Risk of Myocardial Infraction Study, a cross-sectional study based in Pakistan, we calculated body mass index (BMI) variance estimates (square of the residual of inverse-normal transformed BMI z-score) in 14 131 participants and conducted genome-wide heterogeneity of variance analyses (GWHVA) for this outcome. All analyses were adjusted for age, age(2), sex and genetic ancestry. RESULTS: The GWHVA analyses identified an intronic variant, rs140133294, in the FLJ33544 gene in association with BMI variance (P-value=3.1 × 10(-8)). In explicit tests of gene × lifestyle interaction, smoking was found to significantly modify the effect of rs140133294 on BMI (Pinteraction=0.0005), whereby the minor allele (T) was associated with lower BMI in current smokers, while positively associated with BMI in never smokers. Analyses of ENCODE data at the FLJ33534 locus revealed features indicative of open chromatin and high confidence DNA-binding motifs for several transcription factors, providing suggestive biological support for a mechanism of interaction. CONCLUSIONS: In summary, we have identified a novel interaction between smoking and variation at the FLJ33534 locus in relation to BMI in people from Pakistan.

Detection of cryptosporidium in immunosuppressed patients.

BACKGROUND: Cryptosporidium is an important cause of diarrhoeal disease in children and immunosuppressed persons. It is an opportunistic pathogen. A study was done to determine the frequency of Cryptosporidium in immunosuppressed persons. METHODS: Fecal samples were collected from Jinnah Postgraduate Medical Centre Karachi during July to December 2003 and they consisted of three categories of patients which included cancer patients (10) diabetics (20) and patients on dialysis (20). Direct microscopy in saline and iodine was done to detect parasites. Detection of Cryptosporidium from fecal samples was done by Kinyoun method. Bacteriological study was also done to determine any bacterial pathogens. RESULTS: Out of 50 fecal samples Cryptosporidium was found in 20 (40%) of cases. Among the different groups Cryptosporidium was found in 80% of cancer patients, 25% diabetics and 35% dialysis patients. Distribution of Cryptosporidium according to gender indicated more cases in males (87%) among cancer patients and 40% among dialyzed patients while diabetic patients showed similar distribution. Among the different age groups male patients were found to be between 40-49 years group for all categories of patients while more positive cases were detected in females in 30-39 years age group. Direct microscopy did not indicate any ova or parasite and bacteriological study indicated Salmonella and Shigella spp. in stool samples. CONCLUSION: This study provides indication of the possibility of Cryptosporodisis in immunosuppressed patient and further comprehensive study is required to clearly establish the relationship of opportunistic infections in immunosuppressed patients.

Inhibitory effect of IL-4 on the production of IL-1 beta and TNF-alpha by gastric mononuclear cells of Helicobacter pylori infected patients.

BACKGROUND: The mechanisms by which Helicobacter pylori damages host tissues are complex and unclear. AIMS: To determine the effect interleukin (IL)-4 and interferon-gamma (IFN-gamma) on the production of proinflammatory cytokines by the gastric mononuclear cells of H. pylori infected patients was determined. METHODS: The effect of IL-4 and IFN-gamma on the production of proinflammatory cytokines by the gastric mononuclear cells of H. pylori infected patients was determined. RESULTS: IL-4 markedly reduced the production of IL-1 beta and tumour necrosis factor-a (TNF-alpha) by the gastric mononuclear cells of H. pylori infected patients (P < 0.01). Enzyme-linked immunospot (ELISPOT) assay indicated a decrease in IL-4 producing cells (P < 0.05) and an increase in IFN-gamma secreting cells (P < 0.01). CONCLUSIONS: The increased level of proinflammatory cytokines may be due to hyposecretion of IL-4 in H. pylori infected patients. T helper type 1 (Th1) immune response with increased IFN-gamma also contributes to the inflammation of the gastric mucosa.

Reciprocal, temporal expression of SpeA and SpeB by invasive M1T1 group a streptococcal isolates in vivo.

The streptococcal pyrogenic exotoxins (Spes) play a central role in the pathogenesis of invasive group A streptococcal (GAS) infections. The majority of recent invasive GAS infections have been caused by an M1T1 strain that harbors the genes for several streptococcal superantigens, including speA, speB, speF, speG, and smeZ. However, considerable variation in the expression of Spe proteins among clonal M1 isolates has been found, and many of the speA-positive M1 strains do not produce detectable amounts of SpeA in vitro. This study was designed to test the hypothesis that speA gene expression can be induced in vivo. A mouse infection chamber model that allows sequential sampling of GAS isolates at various time points postinfection was developed and used to monitor the kinetics of Spe production in vivo. Micropore Teflon diffusion chambers were implanted subcutaneously in BALB/c mice, and after 3 weeks the pores became sealed with connective tissue and sterile fluid containing a white blood cell infiltrate accumulated inside the infection chambers. Representative clonal M1T1 isolates expressing no detectable SpeA were inoculated into the implanted chambers, and the expression of SpeA in the aspirated aliquots of the chamber fluid was analyzed on successive days postinfection. Expression of SpeA was detected in the chamber fluid as early as days 3 to 5 postinfection in most animals, with a significant increase in expression by day 7 in all infected mice. Isolates recovered from the chamber and grown in vitro continued to produce SpeA even after 21 passages in vitro, suggesting stable switch on of the speA gene. A temporal relation between the upregulation of SpeA expression and the downregulation of SpeB expression was observed in vivo. These data suggest that in vivo host and/or environmental signals induced speA gene expression and suppressed speB gene expression. This underscores the role of the host-pathogen interaction in regulating the expression of streptococcal virulence factors in vivo. The model described here should facilitate such studies.

Role of cytokines in giardiasis.

OBJECTIVES: The purpose of this study was to determine the relationship of inteleukins with G. lamblia infection. METHODS: Serum interleukins were estimated in 42 patients suffering from giardiasis and 42 apparently healthy controls. Tumor Necrosis Factor (TNF) was also studied in 14 patients and 14 controls. Interleukins (IL-2, IL-4, IL-10) and TNF alpha were determined by ELISA. RESULTS: IL-4 was present in 14 (33.3%) patients (mean value 220 pg/ml) and 8 (19%) controls (mean value 93 pg/ml). IL-10 was present in 5 (12%) patients (mean value 57 pg/ml) and 6 (14%) controls (mean value 79 pg/ml). IL-2 was present in one patient only but absent in controls. TNF alpha was not detected in patients but was present in 2 (14.2%) controls (mean value 75 pg/ml). CONCLUSION: Results indicate that IL-4 being an inflammatory regulator appears to have some relationship with giardiasis, while TNF alpha was not detected in patients probably because G. lamblia is a non invasive parasite.

Breast feeding may protect children against Campylobacter jejuni associated diarrhoea.

PIP: To investigate the bacterial etiology of infant diarrhea in Karachi, Pakistan, 180 rectal swab samples collected from diarrhea patients under 5 years of age and 30 samples from age- and sex-matched healthy children were analyzed. Enteropathogenic organisms were isolated from 70 case samples (38.9%). The two most common etiologic agents were Campylobacter jejuni (19.4%) and Aeromonas hydrophilia (6.1%). Salmonella, Shigella, and Yersina appear to have a limited incidence in this age group. None of the control specimens yielded any enteropathogen. Breast-fed infants had a significantly lower risk of enteric infection. A pathogen was isolated in 26.0% of samples from breast-fed children with diarrhea compared with 46.8% of samples from bottle-fed diarrhea patients. All C jejuni infections identified in this study involved bottle-fed children. Boiled water was used to prepare infant formula in only 31.1% of these patients. These findings are consistent with those of other studies showing a decreased rate or severity of diarrhea in breast-fed infants. Mothers should be encouraged to breast feed their infants or, if this is not possible, to use boiled water for the preparation of infant formula.^ieng

The immune function and measles virus infection in three different socioeconomic child populations in Karachi, Pakistan.

The immune function as well as anti-measles virus antibody level were investigated with 111 children in Karachi who were classified into high-, middle- and low-income groups. No difference in the blood cell counts or the biochemical data among three groups indicates no marked difference in the general health conditions among them. In the low-income group, levels of IgG, IgA and anti-measles virus antibody were significantly higher than those in the other two groups. Although 30% of children of the low-income group kept extremely high levels of immunoglobulin, no significant correlation was observed between IgG levels and anti-measles virus antibody levels. In the high-income group, the level of IgM was significantly lower and the incidence of anti-measles virus antibody-negative children was high (7/38; 18.4%). These antibody-negative children kept lower immunoglobulin levels although they were over four years old. These results suggest that the living environmental conditions of these different socioeconomic groups vary greatly and hygienic conditions must influence the chance of encountering infectious pathogens including measles virus. The relation between living environment and risk of subacute sclerosing panencephalitis (SSPE) in child population of Krachi is discussed.

Anti-tumor effect of human lymphocytes and interleukin-2.

We studied the anti-tumor effect of control human lymphocytes and interleukin-2 (IL-2) activated lymphocytes (lymphokine activated killer cells, LAK-cells), on two different cell lines: SW742 human colon adenocarcinoma and K562 human myeloid leukaemia cell line. Our results indicate that IL-2 augment the anti-tumor activity of human lymphocytes and these LAK-cells lyse the tumor cells very efficiently. Furthermore, we treated the target cells (SW742 and K562) with different cytokines in order to establish whether these cytokines have any effect on susceptibility to lysis by LAK-cells. Anti-tumor activity of human lymphocytes and IL-2 is discussed in this study.

An antitumor cardenolide with inhibitory activity against pseudomonas pseudomallei.

The antibacterial activity of a new cardenolide, 7beta, 14beta - dihydroxy-5-card-20(22) enolide has been studied and it has been found to be active against Pseudomonas pseudomallei. The new cardenolide also exhibited antitumor activity in a potato disc assay.

Prevalence of Chlamydia trachomatis infections in Karachi, Pakistan.

An epidemiological study was carried out to determine the prevalence of Chlamydia infections in adult females by enzyme immunoassay and microscopic examination of Giemsa-stained smears. Endocervical swabs were collected from 126 females attending OB/GYN ward at Abbasi Shaheed Hospital, Karachi. 13.5% of 126 females tested were positive by enzyme immunoassay and only 5.6% were positive by the Giemsa-staining method. The infection rate among pregnant and nonpregnant women with urinogenital problems were 11.8% and 14.7%, respectively. The majority of females complained of excessive cervical discharge and pain in the lower abdomen. A high prevalence of infection in normal pregnant women (18.2%) indicates the asymptomatic nature of this infection.

New bioactive compounds of plant origin.

Crude extracts of Withania somnifera (WS) and Polygonum equisetiforme (PE) as well as the pure compounds isolated therefrom were screened for antibacterial and antifungal activity against 20 bacterial and 17 fungal cultures. The crude extract of PE and WS inhibited the growth of T. mentagrophyte, M. canis and A. boydii at an MIC of 450-500 microg/ml whereas the pure compounds inhibited the growth at MIC of 300-350 micro/ml. Species of Corynebacterium, Bacillus, Streptococcus and Staphylococcus were found to be highly susceptible to both the crude sad the pure compounds. MIC values of both crude extracts for different organisms tested were found to be higher (200-350 microg/ml) than the pure compounds (150-170 microg/ml). The crude extract of PE did not inhibit the growth of Ps. aeruginosa, however, the pure compound was found to be bacteriostatic. Brine shrimp and BALB/c mice lethality test indicated that these extracts maybe toxic at high concentration.

Response of Campylobacter jejuni to combinations of ferrous sulphate and cadmium chloride.

On Mueller Hinton (MH) agar, Campylobacter jejuni showed 20.0 and 30.9 mm zones of inhibition surrounding discs impregnated with 2.5 and 20 micrograms CdCl2 respectively. The minimal inhibitory concentration (MIC) ranged from 0.64 to 3.2 micrograms CdCl2/ml of MH agar for four C. jejuni strains. In the presence of 23 micrograms FeSO4/ml of MH the MIC increased to a range of 1.5-5.4 micrograms CdCl2/ml of MH. Moreover, the numbers of colonies present on MH supplemented with FeSO4 were greater than on MH without iron. The growth response of C. jejuni in the presence of 0.025% (w/v) FeSO4 in MH broth was increased about 10,000 fold in three of four strains when compared with the growth in unsupplemented MH broth. Zones of inhibition surrounding 20 micrograms discs of CdCl, were 50.6 and 24.4 mm on MH and Campy-BAP media respectively, with cells grown on MH. These results suggest that the blood-containing medium 'neutralized' the biocidal influence of the CdCl2. In comparison, C. jejuni inoculum from fluid thioglycollate (FT) medium showed smaller zones of inhibition. These decreased from 34.9 mm on MH agar to 19.6 mm on Campy-BAP agar, suggesting that components in the FT growth medium ameliorated the toxic influence of CdCl2. Atomic absorption spectroscopy analysis indicated mean values (mg/100 g dry weight) of selected metals bound by C. jejuni as: Cu, 10.4; Mg, 146; Na, 2385; Fe, 45.1; Zn, 13.0; and K, 172.

Cadmium chloride susceptibility, a characteristic of Campylobacter spp.

We report a simple diagnostic characteristic useful in the presumptive identification of Campylobacter jejuni and Campylobacter coli. Filter paper disks impregnated with cadmium chloride were placed on streaked agar medium. Zones of growth inhibition for Campylobacter spp. occurred at 1.25 micrograms per disk. Other enteropathogens (Salmonella spp., Shigella spp., Vibrio cholerae, Vibrio parahaemolyticus, Escherichia coli, and Yersinia enterocolitica) were resistant to at least 40 micrograms per disk, with the exception of a strain of Shigella flexneri, which showed first susceptibility at 10 micrograms per disk. Most of the 52 Campylobacter strains, which were isolated from human clinical and animal sources, showed zones of inhibition greater than 10 mm with 2.5 micrograms of cadmium chloride per disk. At 20 micrograms per disk, Campylobacter isolates from clinical sources were significantly (P less than 0.01) more susceptible to cadmium chloride inhibition than were those from meat samples.