Diagnostic Accuracy of Flow Cytometric DNA Index in Saudi Children with B Cell Acute Lymphoblastic Leukemia.

B cell Acute Lymphoblastic Leukemia (B-ALL) is one of the most common types of cancer diagnosed in children in Saudi Arabia. Cytogenetic investigations, including karyotyping and FISH, are used to determine the incidence and prognostic significance of chromosomal abnormalities in B-ALL. However, in ALL, accurate identification of the morphology of chromosomes is sometimes not achieved. Flow cytometric DI may have the advantage of being technically fast, using either fresh or frozen samples to correctly stratify the patient into the appropriate risk group for treatment. In this study, we evaluated the reliability and validity of using fixed samples instead of fresh samples to determine aneuploidy in cancer cells using a DNA index. The results of the DNA index obtained by flow cytometry were compared with those of conventional cytogenetic analysis to validate the accuracy. Fixed samples (n = 72) from children diagnosed with B-ALL at King Fahad Medical City in Riyadh between 2017 and 2019 were investigated. The results showed strong and statistically significant positive correlation between DNAI-FCM and conventional cytogenetic analysis (p = 0.000 < 0.01). The DNA index value by flow cytometry was proportional to the cytogenetic study in 94.36% (67) of the cases, while discrepancy was observed in 5.6% (four) cases. Our findings highlight the ability of the DNA index method to provide complementary information for the accurate diagnosis of aneuploidy in patients with B-ALL.

Detection of Radiolabeled Inflammatory Cell Macrophage Subpopulations in Chronic Respiratory Diseases: Results from Preliminary Analyses.

Chronic respiratory diseases (CRDs) like asthma and chronic obstructive pulmonary disease (COPD) are the leading causes of morbidity and mortality worldwide. Alveolar macrophages (AM) are immune cells that exist in different polarization states/phenotypes and have been shown to play a critical role during an inflammatory process. In this paper, differently polarized mouse bone marrow-derived macrophages (BMDM (M1-proinflammatory or M2-immunomodulator)) were radiolabeled with either 99mTc-D,L-hexamethylene-propyleneamine oxime (99mTc-HMPAO), 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG), or 67Ga-citrate. Biocompatibility and in vivo biodistribution of radionuclide-labeled macrophages after intravenous injection were evaluated. Radioactivity measurements were performed using Packard Cobra Quantum 5002 Gamma Counter. Both M1 and M2 macrophages showed a higher uptake for 18F-FDG and 99mTc-HMPAO, than 67Ga-citrate. M2 macrophages showed a higher uptake of radionuclides than M1 macrophages. The used radionuclides were biocompatible for both M1 and M2 macrophages. At 2-hour postinjection, 18F-FDG-labeled M1 and M2 macrophages were found significantly higher in the lung of inflammatory animals (12.54 ± 1.58% and 14.13 ± 1.03%, respectively) than in control mice. Labeling macrophages with either 18F-FDG or 99mTc-HMPAO did not affect their biodistribution. The results from these initial experiments indicate that radionuclide-labeled macrophages may allow a higher sensitivity detection in nuclear imaging techniques such as PET and SPECT. Further confirmatory studies are needed to noninvasively image radiolabeled BMDM to understand their role in the inflammatory processes inherent to CRDs.

Gene expression patterns of COX-1, COX-2 and iNOS in H. Pylori infected histopathological conditions.

BACKGROUND: Research indicates that Helicobacter pylori can inflict severe histological damage through the modulation of host-related genes. The current study investigated the effect of H. pylori genotypes in the outcome of disease, and the expression of anti-apoptotic related genes, COX-1, COX-2, and iNOS genes in benign, pre-malignant, and malignant lesions of gastric carcinogenesis. MATERIALS AND METHODS: Tissue samples from H. pylori positive patients were graded based on the genotype of the infected H. pylori strain. Expression of COX-1, COX-2 and iNOS was assessed using a combination of real-time PCR and immunohistochemistry. RESULTS: Gene expression studies confirmed that COX-2 and iNOS expression was highly and selectively induced in epithelium with premalignant changes such as atrophic conditions, metaplasia and dysplasia, suggesting an important role of these genes in the sequence to gastric carcinoma of the intestinal type. Furthermore, the expression of COX-2 and iNOS was also dependent on the genotype of H. pylori and subjects with genotype-1 exhibited significantly higher expressions of COX-2 and iNOS compared to other genotypes. Comparison of the expression levels among infected and uninfected individuals demonstrated significant difference in the expression pattern of COX-2 gene whereas iNOS expression was found only in subjects infected H. pylori (p < 0.001). Immunohistochemical staining showed 1.5619 folds higher propensity of COX-2 and 3.2941 folds higher intensity of iNOS expression in subjects infected with H. pylori genotype 1. CONCLUSION: The up-regulation of COX-2 and iNOS was associated with the genotype of the H. pylori strain and the presence of certain genotype may greatly affect early events during carcinogenesis.

Vitamin D Receptor FokI, ApaI, and TaqI Polymorphisms in Lead Exposed Subjects From Saudi Arabia.

Vitamin D receptor (VDR) gene polymorphisms were reported to influence blood lead levels (BLL) and the response of subjects to the symptoms of lead toxicity. However, no studies have been conducted in the Saudi Arabian population which has unique ethnicity and socio-demographic features. This study examined the polymorphisms in exon 2 (allele 1) and intron 8 (allele 2 and allele 3) of VDR gene and their relation to BLLs. As per the CDC guidelines, the recruited lead-exposed workers (N = 130) were categorized to two groups viz., low BLL group (<10 µg/dL) and high BLL group (>10 µg/dL). The low BLL group had a mean BLL of 4.37 µg/dL, while the high BLL group had levels of 18.12 µg/dL (p < 0.001). Overall, the genetic variants, TC and CC in the VDR FokI were significantly associated with a risk of lead toxicity and the allele "C" was a risk factor (p = 0.00026). Furthermore, the TT genotype of VDR ApaI significantly increased the risk of developing lead poisoning (p = 0.0006). The VDR TaqI SNP was not significantly associated with lead toxicity. The highest BLLs for VDR FokI-CC, VDR ApaI-GG, and VDR TaqI-TT genotypes from High BLL group were 18.42, 15.26, and 18.75 µg/dL, respectively. Older age (51-60 years) was found to be a significant confounding factor for BLLs (p = 0.012). Additional studies in larger sample sizes are needed to firmly establish the role of VDR genotypes and genetic susceptibility to lead poisoning.

Effect of polyethylene glycol surface charge functionalization of SWCNT on the in vitro and in vivo nanotoxicity and biodistribution monitored noninvasively using MRI.

The current study evaluated in vitro and in vivo toxicity of carboxyl or amine polyethylene glycol (PEG) surface functionalization of single-walled carbon nanotubes (SWCNTs). Assessments of cytotoxicity, genotoxicity, immunotoxicity, and oxidative stress were performed in vitro and in vivo (in a 1-month follow-up study). The SWCNT biodistribution was investigated using noninvasive magnetic resonance imaging (MRI). Results confirmed the enhanced biocompatibility of PEG-functionalized SWCNTs compared to non-functionalized materials with significant decreases (p < 0.05) in the percentage of cell viability and increases in ROS generation, mitochondrial membrane potential, cell apoptosis, oxidative stress generation, and oxidative DNA damage in vitro. PEG-functionalized SWCNTs with amine terminals were found to induce prominent increases in ROS generation, mitochondrial membrane potential, and oxidative stress compared to carboxy functionalization. No significant difference in the biodistribution of either functionalized SWCNTs was observed in MRI. In vivo assessments revealed a statistically significant increase (p < 0.05) in oxidative stress as early as 24 h in serum and liver; however, all values normalized at 2 weeks' investigation time point. DNA damage was minimal with either PEG-COOH or PEG-NH2 functionalized SWCNTs after 2 weeks' exposure. The negatively charged SWCNTs caused lesser DNA damage compared to positively charged samples. Carboxy-functionalized SWCNTs did not cause substantial changes in inflammatory mediators and were found to be significantly safer than non-functionalized SWCNTs and may pave the way for novel biomedical applications in cancer diagnosis and therapy.

Blocking Interleukin-4 Receptor α Using Polyethylene Glycol Functionalized Superparamagnetic Iron Oxide Nanocarriers to Inhibit Breast Cancer Cell Proliferation.

PURPOSE: The specific targeting of interleukin-4 receptor α (IL4Rα) receptor offers a promising therapeutic approach for inhibition of tumor cell progression in breast cancer patients. In the current study, the in vitro efficacy of superparamagnetic iron oxide nanoparticles conjugated with anti-IL4Rα blocking antibodies (SPION-IL4Rα) via polyethylene glycol polymers was evaluated in 4T1 breast cancer cells. MATERIALS AND METHODS: Cell viability, reactive oxygen species generation, and apoptosis frequency were assessed in vitro in 4T1 cancer cell lines following exposure to SPION-IL4Rα alone or combined with doxorubicin. In addition, immunofluorescence assessments and fluorimetrywere performed to confirm the specific targeting and interaction of the developed nanocarriers with IL4Rα receptors in breast cancer cells. RESULTS: Blocking of IL4Rα receptors caused a significant decrease in cell viability and induced apoptosis in 4T1 cells. In addition, combined treatment with SPION-IL4Rα+doxorubicin caused significant increases in cell death, apoptosis, and oxidative stress compared to either SPION-IL4Rα or doxorubicin alone, indicating the enhanced therapeutic efficacy of this combination. The decrease in fluorescence intensity upon immunofluorescence and fluorimetry assays combined with increased viability and decreased apoptosis following the blocking of IL4Rα receptors confirmed the successful binding of the synthesized nanocarriers to the target sites on murine 4T1 breast cancerous cells. CONCLUSION: These results suggest that SPION-IL4Rα nanocarriers might be used for successfulreduction of tumor growth and inhibition of progression of metastasis in vivo.

Evaluation of cytotoxicity and genotoxicity of pesticide mixtures on lymphocytes.

The cytotoxicity and genotoxicity of pesticide mixtures viz. endosulfan + chlorpyrifos, chlorpyrifos + profenofos, and endosulfan + profenofos were evaluated on cultured human peripheral blood lymphocytes using assays for cell viability, and genotoxicity using chromosomal aberrations test and comet assay. The LC50 values for cytotoxicity were 3.50 µM, 4.18 µM, and 10.5 µM for profenofos, endosulfan, and chlorpyrifos respectively. When combined in equimolar concentrations, the LC50 values for cytotoxicity were 1.4 µM, 1.8 µM, and 2.0 µM for endosulfan + chlorpyrifos, chlorpyrifos + profenofos, and endosulfan + profenofos, respectively. Higher concentrations of individual pesticides (0.5-4.0 µM) but very low concentrations of pesticide mixtures caused significant DNA damage. Additive index values indicated a synergistic effect of toxicity for endosulfan + chlorpyrifos combination (1.12 TTU). The binary mixture of chlorpyrifos + profenofos showed an additive toxicity (0.46 TTU) while an antagonistic effect was observed for endosulfan + profenofos combination. Synergism could be due to these complementary pesticides simultaneously acting in different ways, magnifying their efficacy, whereas an additive interaction would imply that the chemicals are acting by the same mechanism and at the same target. Analysis of toxicity of pesticide mixtures may serve as important biomarker for occupational and household exposure to pesticides, with different modes of action.

Sodium-22-radiolabeled silica nanoparticles as new radiotracer for biomedical applications: in vivo positron emission tomography imaging, biodistribution, and biocompatibility.

Despite their advantageous chemical properties for nuclear imaging, radioactive sodium-22 ((22)Na) tracers have been excluded for biomedical applications because of their extremely long lifetime. In the current study, we proposed, for the first time, the use of (22)Na radiotracers for pre-clinical applications by efficiently loading with silica nanoparticles (SiNPs) and thus offering a new life for this radiotracer. Crown-ether-conjugated SiNPs (300 nm; -0.18±0.1 mV) were successfully loaded with (22)Na with a loading efficacy of 98.1%±1.4%. Noninvasive positron emission tomography imaging revealed a transient accumulation of (22)Na-loaded SiNPs in the liver and to a lower extent in the spleen, kidneys, and lung. However, the signal gradually decreased in a time-dependent manner to become not detectable starting from 2 weeks postinjection. These observations were confirmed ex vivo by quantifying (22)Na radioactivity using γ-counter and silicon content using inductively coupled plasma-mass spectrometry in the blood and the different organs of interest. Quantification of Si content in the urine and feces revealed that SiNPs accumulated in the organs were cleared from the body within a period of 2 weeks and completely in 1 month. Biocompatibility evaluations performed during the 1-month follow-up study to assess the possibility of synthesized nanocarriers to induce oxidative stress or DNA damage confirmed their safety for pre-clinical applications. (22)Na-loaded nanocarriers can thus provide an innovative diagnostic agent allowing ultra-sensitive positron emission tomography imaging. On the other hand, with its long lifetime, onsite generators or cyclotrons will not be required as (22)Na can be easily stored in the nuclear medicine department and be used on-demand.

Effect of surface coating on the biocompatibility and in vivo MRI detection of iron oxide nanoparticles after intrapulmonary administration.

Superparamagnetic iron oxide nanoparticles (SPIONs) have attracted special attention as novel nanoprobes capable of improving both the therapy and diagnosis of lung diseases. For safe prospective clinical applications, their biocompatibility has to be assessed after intrapulmonary administration. This study was therefore conducted to understand the biological impact of SPIONs and their further surface-functionalization with polyethylene glycol (PEG) having either negative (i.e. carboxyl) or positive (i.e. amine) terminal in a 1-month longitudinal study following acute and sub-acute exposures. Noninvasive free-breathing MR imaging protocols were first optimized to validate SPIONs detection in the lung and investigate possible subsequent systemic translocation to abdominal organs. Pulmonary Magnetic Resonance Imaging (MRI) allowed successful in vivo detection of SPIONs in the lung using ultra-short echo time sequence. Following high-dose lung administration, MR imaging performed on abdominal organs detected transient accumulation of SPIONs in the liver. Iron quantification using Inductive coupled plasma - Mass mass spectroscopy (ICP-MS) confirmed MRI readouts. Oxidative stress induction and genotoxicity were then conducted to evaluate the biocompatibility of SPIONs with their different formulations in a mouse model. A significant increase in lipid peroxidation was observed in both acute and sub-acute sets and found to regress in a time-dependent manner. PEG functionalized SPIONs revealed a lower effect with no difference between both terminal modifications. Genotoxicity assessments revealed an increase in DNA damage and gene expression of CCL-17 and IL-10 biomarkers following SPIONs administration, which was significantly higher than surface-modified nanoparticles and decreased in a time-dependent manner. However, SPIONs with carboxyl terminal showed a slightly prominent effect compared to amine modification.

Magnetic single-walled carbon nanotubes as efficient drug delivery nanocarriers in breast cancer murine model: noninvasive monitoring using diffusion-weighted magnetic resonance imaging as sensitive imaging biomarker.

PURPOSE: Targeting doxorubicin (DOX) by means of single-walled carbon nanotube (SWCNT) nanocarriers may help improve the clinical utility of this highly active therapeutic agent. Active targeting of SWCNTs using tumor-specific antibody and magnetic attraction by tagging the nanotubes with iron oxide nanoparticles can potentially reduce the unnecessary side effects and provide enhanced theranostics. In the current study, the in vitro and in vivo efficacy of DOX-loaded SWCNTs as theranostic nanoprobes was evaluated in a murine breast cancer model. METHODS: Iron-tagged SWCNTs conjugated with Endoglin/CD105 antibody with or without DOX were synthetized and extensively characterized. Their biocompatibility was assessed in vitro in luciferase (Luc2)-expressing 4T1 (4T1-Luc2) murine breast cancer cells using TiterTACS™ Colorimetric Apoptosis Detection Kit (apoptosis induction), poly (ADP-ribose) polymerase (marker for DNA damage), and thiobarbituric acid-reactive substances (oxidative stress generation) assays, and the efficacy of DOX-loaded SWCNTs was evaluated by measuring the radiance efficiency using bioluminescence imaging (BLI). Tumor progression and growth were monitored after 4T1-Luc2 cells inoculation using noninvasive BLI and magnetic resonance imaging (MRI) before and after subsequent injection of SWCNT complexes actively and magnetically targeted to tumor sites. RESULTS: Significant increases in apoptosis, DNA damage, and oxidative stress were induced by DOX-loaded SWCNTs. In addition, a tremendous decrease in bioluminescence was observed in a dose- and time-dependent manner. Noninvasive BLI and MRI revealed successful tumor growth and subsequent attenuation along with metastasis inhibition following DOX-loaded SWCNTs injection. Magnetic tagging of SWCNTs was found to produce significant discrepancies in apparent diffusion coefficient values providing a higher contrast to detect treatment-induced variations as noninvasive imaging biomarker. In addition, it allowed their sensitive noninvasive diagnosis using susceptibility-weighted MRI and their magnetic targeting using an externally applied magnet. CONCLUSION: Enhanced therapeutic efficacy of DOX delivered through antibody-conjugated magnetic SWCNTs was achieved. Further, the superiority of apparent diffusion coefficient measurements using diffusion-weighted MRI was found to be a sensitive imaging biomarker for assessment of treatment-induced changes.

Phylogenetic analysis of cubilin (CUBN) gene.

Cubilin, (CUBN; also known as intrinsic factor-cobalamin receptor [Homo sapiens Entrez Pubmed ref NM_001081.3; NG_008967.1; GI: 119606627]), located in the epithelium of intestine and kidney acts as a receptor for intrinsic factor - vitamin B12 complexes. Mutations in CUBN may play a role in autosomal recessive megaloblastic anemia. The current study investigated the possible role of CUBN in evolution using phylogenetic testing. A total of 588 BLAST hits were found for the cubilin query sequence and these hits showed putative conserved domain, CUB superfamily (as on 27(th) Nov 2012). A first-pass phylogenetic tree was constructed to identify the taxa which most often contained the CUBN sequences. Following this, we narrowed down the search by manually deleting sequences which were not CUBN. A repeat phylogenetic analysis of 25 taxa was performed using PhyML, RAxML and TreeDyn softwares to confirm that CUBN is a conserved protein emphasizing its importance as an extracellular domain and being present in proteins mostly known to be involved in development in many chordate taxa but not found in prokaryotes, plants and yeast.. No horizontal gene transfers have been found between different taxa.

A Phylogenetic analysis of Heparanase (HPSE) gene.

The Current Study aimed to investigate the possible role of Heparanase protein (HPSE-1, [Entrez Pubmed ref|NP_001092010.1|, heparanase isoform 1 preproprotein [Homo sapiens]) in evolution by studying the phylogenetic relationship and divergence of HPSE-1 gene using computational methods. The Human HPSE protein sequences from various species were retrieved from GenBank database and were compared using sequence alignment. Multiple sequence alignment was done using Clustal-W with defaults and phylogenetic trees for the gene were built using neighbor-joining method as in BLAST 2.2.26+ version. A total of 112 BLAST hits were found for the heparanase query sequence and these hits showed putative conserved domain, Glyco_hydro_79n superfamily. We then narrowed down the search by manually deleting the proteins which were not HPSE-1. These sequences were then subjected to phylogenetic analyses using the PhyML and TreeDyn software. Our study indicated that HPSE-1 is a conserved protein in classes Mammalia, Aves, Amphibia, Actinopterygii and Insecta emphasizing its importance in the physiology of cell membranes. Occurrence of this gene in evolution with conserved sites strengthens the role of HPSE-1 gene and helps in better understanding the biochemical processes that may lead to cancer.

Phylogenetic analysis of uroporphyrinogen III synthase (UROS) gene.

The uroporphyrinogen III synthase (UROS) enzyme (also known as hydroxymethylbilane hydrolyase) catalyzes the cyclization of hydroxymethylbilane to uroporphyrinogen III during heme biosynthesis. A deficiency of this enzyme is associated with the very rare Gunther's disease or congenital erythropoietic porphyria, an autosomal recessive inborn error of metabolism. The current study investigated the possible role of UROS (Homo sapiens [EC: 4.2.1.75; 265 aa; 1371 bp mRNA; Entrez Pubmed ref NP_000366.1, NM_000375.2]) in evolution by studying the phylogenetic relationship and divergence of this gene using computational methods. The UROS protein sequences from various taxa were retrieved from GenBank database and were compared using Clustal-W (multiple sequence alignment) with defaults and a first-pass phylogenetic tree was built using neighbor-joining method as in DELTA BLAST 2.2.27+ version. A total of 163 BLAST hits were found for the uroporphyrinogen III synthase query sequence and these hits showed putative conserved domain, HemD superfamily (as on 14(th) Nov 2012). We then narrowed down the search by manually deleting the proteins which were not UROS sequences and sequences belonging to phyla other than Chordata were deleted. A repeat phylogenetic analysis of 39 taxa was performed using PhyML and TreeDyn software to confirm that UROS is a highly conserved protein with approximately 85% conserved sequences in almost all chordate taxons emphasizing its importance in heme synthesis.

Meta-analysis study of glutathione-S-transferases (GSTM1, GSTP1, and GSTT1) gene polymorphisms and risk of acute myeloid leukemia.

To investigate the association of glutathione-S-transferase (GST) polymorphisms with the risk of acute myeloid leukemia (AML), a meta-analysis of case-control studies published between 1998 and 2009 was performed. Pooled odds ratios (ORs) were assessed using both fixed- and random-effects models. Heterogeneity across studies was calculated, and funnel plots were constructed to test for publication bias. Overall, the random-effects OR with GSTM1 null genotype, GSTP1 Val105 allele and GSTT1 null genotype were 1.30 (95% confidence intervals (CI) 1.04-1.62, p = 0.018), 1.03 (95% CI 0.80-1.33, p = 0.80) and 1.24 (95% CI 0.98-1.58, p = 0.06), respectively. Statistically, significant increased risk of AML was observed with GSTM1 while borderline significance was seen with GSTT1 null genotypes. However, fixed-effects model showed significant risk of AML in the presence of null genotypes of GSTM1 and GSTT1(p < 0.05). Significant heterogeneity was found between studies relating to GSTP1 (p = 0.162), however, no heterogeneity was seen in studies that evaluated GSTM1 (Q-value = 44; I(2) = 70.9; p-value < 0.01]; and GSTT1 (Q-value = 26.03; I(2) = 57.74; p-value < 0.01] polymorphisms. From the limited studies on the association of GSTP1 with risk of AML, the role of this gene cannot be ascertained fully. Significant association of these three genes with risk of AML must be evaluated further with respect to population, smoking, eating habits, ethnicity, and race.

Polymorphisms in MGP gene and their association with lead toxicity.

Matrix gamma-carboxy glutamic acid protein (MGP) is a 10-kDa secreted protein containing five residues of the vitamin K-dependent calcium binding amino acid gamma-carboxyglutamic acid (Gla). This study was carried out to examine the effects of MGP gene promoter polymorphism (T-138C) on blood lead levels (BLL) and hematological parameters in 113 battery manufacturing unit workers occupationally exposed to lead and 102 controls. Genotypes for the MGP T-138C polymorphism were determined by PCR and restriction fragment length digestion. BLL were determined by Anode Stripping Voltammetry using ESA Model 3010B Lead analyzer. Complete blood picture (CBP) was analyzed using ADVIA Cell counter for each sample. The frequencies of MGP-TT, CT and CC genotypes in our population were 38.6%, 44.3%, and 17.2%, respectively. The frequencies for T and C alleles were 0.612 and 0.386, respectively. Although BLL did not differ significantly among genotypes; they were higher in workers with TT/CT genotype compared to CC genotype subjects (76-88 microg/dL vs 22-45 microg/dL, p > 0.05). About 29.2% of volunteers (n = 33) from the occupationally exposed group had hemoglobin levels below 10.0 gms/dl. There was no significant difference in total white cell count and platelet count between occupational and non-exposed groups. The possible role of SNPs in the promoter region of MGP gene with relation to lead toxicity was investigated for the first time in the Indian population; although significance could not be achieved in this study, further assessments over a larger population size may help in better understanding of the consequences of lead exposure.

CYP1A1 polymorphisms and risk of prostate cancer: a meta-analysis.

INTRODUCTION: Two common polymorphisms in cytochrome P450; family 1, subfamily A, polypeptide 1 (CYP1A1); have been implicated as a risk factor of prostate cancer, but individual studies have been inconclusive or controversial. We reviewed studies on CYP1A1 polymorphisms in patients with prostate cancer. MATERIALS AND METHODS: The strategy searching in the PubMed was based on combinations of prostate cancer, CYP1A1, CYP1A1 gene polymorphism, and genetic susceptibility. The last search update was May 2008. The retrieved articles and their bibliographies of were evaluated and reviewed independently by 2 experts. We shortlisted 19 studies, of which 14 on sporadic prostate cancer were analyzed. Overall, 2573 patients with prostate cancer and 2576 controls were analyzed. RESULTS: The random effects odds ratio was 1.350 (95% confidence interval, 1.110 to 1.641; P = .003) for T/C polymorphism and 1.085 (95% confidence interval, 0.863 to 1.364; P = .49) for A/G polymorphism. The A/G polymorphism was not associated with increased risk of prostate cancer. However, the T/C polymorphism showed conflicting results in different studies, while overall, this polymorphism showed significant effects on the susceptibility to prostate cancer. There was no significant between-study heterogeneity for both polymorphisms with respect to distribution of alleles. CONCLUSION: This meta-analysis suggests that while the CYP1A1 T/C polymorphism is likely to considerably increase the risk of sporadic prostate cancer on a wide population basis, the A/G polymorphism may not influence this risk. However, the association of polymorphisms may be significant with respect to smoking history, diet habits, ethnicity, and race.

Individual susceptibility and genotoxicity in workers exposed to hazardous materials like lead.

The present study was undertaken to investigate lead-induced toxicity in occupationally exposed humans and to evaluate whether genetic damage can be correlated with the known clinical indicators of lead poisoning. For this purpose, genotoxicity biomarkers along with some clinical indices of lead poisoning were determined in blood samples of battery plant workers and compared with healthy control subjects. Workers had significantly increased chromosomal aberrations, micronuclei and DNA damage compared to the controls. Increased blood lead levels (BLLs), decreased hemoglobin, PCV and symptoms of lead poisoning were used as clinical indices of lead toxicity. In addition gene polymorphisms in ALAD and MGP gene were investigated and correlated with BLL and hemoglobin content. Our results showed no significant effects of the ALAD G177C polymorphism on BLL concentrations and BLL concentrations varied to levels much above the normal reference ranges independent of the genotype. Although, significance could not be achieved, ALAD 1-2/2-2 type subjects had numerically higher BLLs (76.2-89.1 microg/dl), compared to ALAD 1-1 volunteers (21.8-79.1 microg/dl). Similarly, this study also aimed to identify the relation of some SNPs with emphasis on lead toxicity and since MGP gene is an important biomarker associated with calcium metabolism; it was hypothesized that it may be associated with lead toxicity. However, we did not find any significant association of MGP T-138C and lead poisoning. Further studies on the role of gene polymorphisms over a larger population along with genotoxicity parameters and biochemical analyses may serve to understand lead toxicity.

Estimation of apoptosis and necrosis caused by pesticides in vitro on human lymphocytes using DNA diffusion assay.

Organophosphorus pesticides like monocrotophos, profenofos, chlorpyrifos, and acephate are most commonly used in India for agriculture and public health programs. Previous studies have revealed that at low doses, organophosphorus pesticides not only act as genotoxic agents but also affect several other biochemical pathways. The aim of the current investigation was to assess apoptosis and necrosis caused by these pesticides on human peripheral blood lymphocytes under in vitro conditions using the DNA diffusion assay. Our studies have revealed that all the above pesticides induced apoptosis and necrosis in cultured human peripheral blood lymphocytes in in vitro conditions. The results are statistically significant (p < 0.001). Data on these alterations of immune cells are required for understanding the subchronic effects mediated by pesticides on nontarget organisms.

Effect of organophosphorus and organochlorine pesticides (monochrotophos, chlorpyriphos, dimethoate, and endosulfan) on human lymphocytes in-vitro.

The toxicological profile of the four pesticides described herein characterizes its effects on lymphocytes from peripheral blood from healthy donors. The exposure to all pesticides was by direct interaction/incubation with varying concentrations of the pesticide with blood sample in-vitro. The dose response relationship in each case was calculated by applying log tables as LC50 values. Cytotoxicity of these pesticides on lymphocytes was measured using the trypan blue dye exclusion technique. Based on LC50 value, all the four pesticides were found to be highly toxic to lymphocyte culture, among them, monocrotophos and endosulfan were the most toxic and dimethoate was the least toxic. The genotoxicity of the pesticides was also determined by comet assay. The results revealed that the pesticides caused increase in the tail length indicating DNA damage. This study suggests that these pesticides have the capacity to alter the genetic material particularly chromosomes in mammalian cultures. The comet assay used in this study was found to be a sensitive and rapid method to detect genotoxicity of pesticide compounds.