Qualitative Polymerase Chain Research Articles

Detection of Genetically Modified Additives in Meat Products in Riyadh City

Vegetable proteins such as soybean protein have numerous nutritional and functional characteristics, and consequently, their utilization in meat products development has dramatically increased in recent decades. Due to high demands for soybean, transgenic Roundup Ready (RR) soybean line grains were developed and widely distributed into global markets. The current study was designed to investigate the presence of transgenic soybean in meat products sold in Riyadh food retails, Saudi Arabia. After extraction of DNA from meat product samples, qualitative duplex polymerase chain reaction (PCR) was used to detect the genetically modified (GM) soybean products in the meat samples using pairs of primers targeting the lectin gene and the 35S promoter. Real-time PCR was used to quantify the percentage of RR soy products in the positive samples. The results clarified that out of 96 tested meat product samples (minced, burger, luncheon, canned, and sausages), 75 samples were positive for the presence of lectin gene, of which 42 samples representing 43.75% of total meat product samples were positive for the presence of 35S promoter. All positive samples for 35S promoter contained RR soy below 0.1%. The results of the consumer acceptance questionnaire of GM additives in meat products proved the presence of several critical aspects of concerns to consumers of meat products in different localities of Riyadh city.

Detection of chicken DNA in commercial dog foods

BackgroundThese days the number of potential food allergens is very large, but chicken is one of the most common allergens in dogs. Elimination diet is one of the clinical tools for the diagnosis of allergies and allergy tests are not very reliable. The restriction diet is most commonly carried out by feeding pet foods, relying on the ingredients on the label to select an elimination diet not containing previously eaten foods. Unfortunately, mislabeling of pet food is quite common. The purpose of this study was to determine the absence or presence of chicken DNA using both qualitative and quantitative polymerase chain reaction (PCR) analysis methods in dry and wet maintenance complete pet foods for adult dogs. Results were used to verify the declared composition on the labels.ResultsEleven out of fifteen (73%) dog foods were produced as declared by the manufacturer, two of which showed the presence of chicken protein as stated on the label. The remaining nine foods contained amounts of chicken DNA below 1%, consistent with declarations that no chicken was added in the composition. Four of tested dog foods (27%) were not produced consistently with the declaration on the packaging. Two dog foods (one dry and one wet) did not contain the claimed chicken protein. In two foods the addition of chicken DNA was detected at the level of over 2% and almost 6%, respectively.ConclusionsIn this study, we focused on one of the most commonly undeclared animal species on the label—chicken protein—and performed DNA analyzes to investigate possible contamination and mislabeling. The results showed some inaccuracies. However, most of them are trace amounts below 1%, which proves compliance with the label. Our results showed that undeclared animal species can be as common as missing an animal protein declared on the label. The conducted research indicates that both dry and wet analyzed foods should not be recommended as a diagnostic tool in elimination tests, because it may result in false negative results. Over-the-counter maintenance foods for dogs should not be recommended for the diagnosis and treatment of food hypersensitivity.

Evaluation of Utilizing the Distinct Genes as Predictive Biomarkers in Late-Onset Alzheimer's Disease.

Alzheimer's disease (AD) is a neurodegenerative disease that is characterized by a devastating decline in cognitive activities among all types of dementia, and it severely affects the quality of life. Late-onset AD (LOAD) occurs after the age of 65 years and develops sporadically. Although aging comes first along the main risk factors underlying LOAD, disease-causing susceptibility genes have been associated with disease pathogenesis. In our study, we included the genes PARP1 , POLB , HTRA2 , SLC1A2 , HS1BP3 , and DRD3 to be investigated in LOAD patients based on their expression levels. Within this framework, we aimed to determine the possible functions of these genes in the pathophysiology of the disease. We investigated whether the utilization of these genes as biomarkers in the early diagnosis of LOAD may help the treatment scheme to be applied in the clinic. We involved 50 individuals in the study and collected peripheral blood samples from the patients and control groups for molecular genetic analysis. Subsequently, RNA was extracted from the peripheral blood samples, and expression analyzes were performed using qualitative reverse transcription polymerase chain reaction. The results obtained were evaluated by using proper statistical methods. Our results demonstrated that there was no difference between patient and control groups in terms of HTRA2 , DRD3 , HS1BP3 , and POLB genes. The expression levels of the SLC1A2 and PARP1 genes were significantly lower in the patient group compared with the control group. In conclusion, we presume that the PARP1 and SLC1A2 genes can be utilized as molecular biomarkers for LOAD.

Prognostic impact of fibroblast growth factor receptor (FGFR) genomic alterations and outcomes in patients with metastatic urothelial.

537 Background: FGFR mutations/translocations are druggable targets in metastatic urothelial cancer (mUC). However, the prognostic effect of these genomic alterations (GA) and their role in the response to conventional therapy remain poorly characterized. Methods: We undertook an observational retrospective study in four Academic Hospitals in Madrid, Spain. Clinical and molecular information of patients diagnosed of Urothelial Cancer (UC) between January 2010 and December 2020 was systematically reviewed. The objective of this work was to compare the outcome of mUC patients with GA in the FGFR 2-3 genes versus wild type tumors. Analyses for detection of FGFR translocations and mutations using DNA isolated from formalin-fixed and paraffinized tumor tissue samples consisted of either next-generation sequencing (Foundation One test; n = 68) or qualitative real-time polymerase chain reaction–based assays (n = 9) with TFGFR or QIAGEN therascreen® tests that evaluated somatic mutations within the FGFR2-3 gene: R248C, S249C, G370C and Y373C and fusions: FGFR3-TACC3v3, FGFR3-TACC3v1 and FGFR3-BAIAP2L1, FGFR2-BICC1 and FGFR2-CASP7. Overall response rate (ORR), Progression Free Survival (PFS) and Overall Survival (OS) were determined and Cox-regression analysis were performed to assess the prognostic impact of these alterations. Results: We identified 201 patients diagnosed with UC. Genomic profiling was available in 77 mUC with 28 patients harboring any FGFR GA. Regarding ORR to first line a trend towards a better outcome was identified in FGFR GA (mutation/translocation/fusion) vs wild type cases (57,7% vs 45,5%, p=0,46). However, median OS was significantly worse among FGFR GA (mutation/translocation) vs FGFR wt tumours (13.8 vs 26.2 months, p=0,021). Prognostic factors associated with an unfavorable outcome in multivariable analysis were visceral metastases (HR 7,29 95% CI 1.6-32,3), ECOG >1 (HR 7,03 95% CI 2,59-19,1), first line treatment with checkpoint inhibitors (HR 2,67; 95% CI 1,06-6,74) and the presence of FGFR GAs (HR 2,98, 95% CI 1.37-6.5). Conclusions: Despite a better response to first line treatment, overall FGFR GA showed to be an independent risk factor in mUC. Thus, this determination should be included in new prognostic models.[Table: see text]

DETECTION OF MINIMAL TUMOR CELLS FOR THE DIAGNOSIS AND TREATMENT MONITORING OF CHILDREN WITH NEUROBLASTOMA

Diagnosis, treatment and designing an adequate strategy of neuroblastoma (NB) therapy in children is still a complicated tasks for pediatric oncology and hematology. One of the key aspects of NB control is detection and monitoring of minimal residual disease.The authors make a concise review of the up-to-date methods, such as immunocytochemistry, fluorescent in situ hybridization (FISH), flow cytometry, the methods of qualitative and quantitative polymerase chain reaction (PCR) to estimate mRNA (RT-PCR and QRT-PCR), which are currently used for minimal residual disease detection in patients with NB. Disialoganglioside GD2, a specific NB marker, is traditionally determined by immunocytochemistry with fluorochromes that enhance its specificity, and by flow cytometry, as well. At present, FISH test is a gold standard for evaluation of the MYCN gen status in NB. A widely used multicolor flow cytometry method allows achieving high specificity of the analysis for NB diagnosis. RT-PCR may search for various targets to reveal NB cells, however, at the moment the only accepted immune target is tyrosine hydroxylase mRNA. Moreover, the studies established that quantitative QRT-PCR has more advantages than traditional qualitative RT-PCR, since this method allows a more accurate and quantitative detection of one or several mRNAs in clinical samples. The review discusses advantages and disadvantages of the main methods currently used for minimal residual disease evaluation of NB cells, such as RT-PCR, flow cytometry, FISH, etc. Comparative studies included multicolor flow cytometry with various combinations of CD9/CD81/CD56/CD45/GD2 monoclonal antibodies, conventional RT-PCR and quantitative QRT-PCR to reveal circulating/disseminated NB cells in the clinical samples of cancer patients and healthy volunteers.The authors analyze the results of various studies that compared accuracy and sensitivity of diagnostic methods such as RT-PCR, flow cytometry, FISH and some others. Despite the advantages of each method, the authors emphasize that multicolor flow cytometry is the optimal approach for the rapid and reliable detection of minimal residual disease and micrometastases of NB.

Relapse of clinical symptoms of COVID-19 or probable reinfection in a laboratory professional: a case report from Northeast Brazil

Healthcare professionals constitute one of the groups that are most vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Herein, we report the case of a non-overweight and non-smoking 42-year-old woman with thrombophilia due to methylenetetrahydrofolate reductase (MTHFR) gene mutation, hereditary renal cysts, and no history of diabetes or arterial hypertension, who presented the first symptoms between 10 and 17 August 2020, with a SARS-CoV-2-positive naso-oropharyngeal swab by qualitative real-time polymerase chain reaction (RT-PCR). However, the result for SARS-CoV-2 immunoglobulin G (IgG) was non-reactive 41 days after (21 September 2020) the onset of symptoms. Nevertheless, on 7 October 2020 (57 days after the first symptoms), the patient presented new symptoms suggestive of COVID-19, with another SARS-CoV-2-positive RT-PCR result, and on 21 October 2020, SARS-CoV-2 immunoglobulin G was positive. Considering this, we interrogated the results to determine whether the case was reinfection or reactivation. This outcome highlights the importance of surveillance over relapses or reinfections.

Development and analytical validation of real-time PCR for the detection of Streptococcus agalactiae in pregnant women

BackgroundGroup B Streptococcus (GBS) is the leading cause of invasive neonatal infection. In this study, we aimed to evaluate the analytical validation of qualitative real-time polymerase chain reaction (qPCR) as a means to detect GBS.MethodsGenomic DNA (gDNA) was purified from 12 ATCC bacterial strains, two belonging to GBS and the remainder acting as negative controls. Additionally, gDNA was isolated from 21 strains of GBS from various serotypes (Ia, Ib and II-VIII). All gDNA was used to evaluate the analytical validation of the qPCR method employing a specific Taqman probe. Inclusivity, exclusivity, anticipated reportable range, the limit of detection and robustness were evaluated. The methods used are described in international guidelines and other existing reports. The performance of this qPCR method for detecting GBS was compared to other microbiological methods used with vaginal-rectal samples from pregnant women.ResultsOur qPCR method for detecting GBS was analytically validated. It has a limit of detection of 0.7 GE/μL and 100% analytical specificity. It detects all strains of GBS with the same level of performance as microbiological methods.ConclusionData suggest that this qPCR method performs adequately as a means to detect GBS in vaginal-rectal swabs from pregnant women.

Clinical diagnostic criteria of efficiency for combined etiopathogenetic therapy in patients with chronic Epstein–Barr virus infection

Treatment of chronic viral infections accompanied by permanent virus persistence in the target epitopes of the oral cavity, skin, urogenital tract is complicated by virtual lack of available drugs exerting combined systemic virulicidal and immunomodulatory effects. Here we demonstrate clinical and immunological efficacy of combined therapy in treatment of Epstein–Barr virus (EBV)-associated chronic infections. The aim of the study was to evaluate the clinical and immunological efficacy of combined etiopathogenetic therapy using the Acegram cosmetic product in patients with EBV-associated chronic infections. Materials and methods. There were enrolled 40 patients monitored before treatment as well as 20 patients followed up after combination therapy (cycle therapy consisted of oral valaciclovir (Valtrex) applied at dose of 500 μg twice a day for 10 days, glucosaminylmuramyldipeptide (Licopid) — 10 mg 2 twice a day for 10 days, topical irrigation for mucous membranes with granulocyte-macrophage colony-stimulating factor active center-derived peptide (Acegram-spray) 3 times a day for 10 days. If necessary, treatment courses were repeated 20 days after the onset. All patients were examined for the presence of EBV genomes in the oral fluid and blood using the qualitative and quantitative polymerase chain reaction (PCR) using the DNA technology test system (Russia) on a DT-Lite device prior treatment and 30, 60 days post-therapy time points. In addition, serum samples were analyzed for level of class G immunoglobulins specific to the EBV nuclear and capsid antigens by using enzyme immunoassay (test systems manufactured by CJSC Vector Best, Russia) as well as immune status (clinical methods, enu flow cytometry evaluation of the phagocytic activity of neutrophils, ELISA method). Results. Use of single or two course combination therapy in subjects with fully eradicated EBV carriage associated with reversed clinical symptoms was accompanied by recovered immune system status (T and B cells, T-helper cells, CD3+ CD25+ cells, phagocytosis parameters). A non-invasive approach proposed for controlling virus elimination in the oral fluid by using polymerase chain reaction method may serve as to objectively monitor therapeutic efficacy.

Response to immunotherapy, platinum-based chemotherapy or their combination in metastatic urothelial carcinoma (MUC) with or without FGFR-3 alterations: Single cohort experience.

560 Background: Fibroblast growth factor receptor-3 (FGFR-3) is a promising target therapy in metastatic urothelial carcinoma. Its role in patient’s clinical outcome and treatment response is unclear. We present data for overall survival (OS) and response to platinum-based treatment, immunotherapy and combination (platinum plus immunotherapy) in MUC. Methods: Enrolled patients were diagnosed with muscle-invasive urothelial cancer (MIUC) between 2/2009-6/2019 at Clinic Hospital of Barcelona, Spain. All have been screened for FGFR-3 alterations using next-generation sequencing or qualitative real-time polymerase chain reaction-based assays in tumour or blood. Demographic, pathology, treatments and treatment response were collected retrospectively. Results: 101 patients with MIUC were screened, 99% had progressed to metastatic stage. At diagnosis 32.67% were metastatic. 77% were man and median age was 68y (38-85y). Median follow-up (FU) since metastatic disease was 16.25 months (1.2-89.72m) with 69.31% of patients had died at cut-off. 32% presented FGFR-3 alteration (fusion =1 and mutation=31). FGFR-3 altered more frequently had papillary histology than FGFR-3 wild type tumours (69 vs 26%, p<0.05). No statistical differences were detected between both groups for gender, age, stage at diagnosis, median FU, primary tumour site (upper vs lower tract) or previous history of non-invasive urothelial carcinoma. 58% patients received 1st line platinum-based chemotherapy, 25% immunotherapy and 8% the combination of both (9% with other therapies). FGFR-3 altered tended to present more benefit (complete, partial response or stable disease) with platinum-based chemotherapy than FGFR-3 wild type (81% vs 62%) but without reach statistical significance. No differences were detected for immunotherapy or combination therapies. Moreover, OS was similar for FGFR-3 altered (median 14.6m) and FGFR-3 wild- type (median 17.1 m) (HR 0.76, p=0.3). Conclusions: In our series, no significant differences related to response to first line therapy or survival was observed.

Evaluation of the prevention of mother-to-child transmission programme at a primary health care centre in South Africa

Aim: To evaluate the effectiveness of the prevention of mother-to-child transmission (PMTCT) of the HIV programme at Levai Mbatha Community Health Centre (CHC), Evaton, South Africa.
 
 Methods: A retrospective analysis of HIV-infected mother–infant pairs was conducted between 1 August 2009 and 31 July 2010. The infants’ HIV status was determined using HIV-specific qualitative DNA polymerase chain reaction (PCR). Demographic characteristics, mode of mother to child transmission (MTCT), choice of infant feeding, mode of delivery and CD4 count were included.
 
 Results: Of the 206 mothers, 10 infants had positive DNA PCR results at 6 weeks. The MTCT rate was 4.9%. The mean age of HIV-infected mothers was 28 years (SD 5.7, range 16–42 years). Overall, 74.2% (152) of HIV-positive mothers received dual therapy
 and 28.8% (53) were on HAART alone. Mothers with CD4 count < 200cells/μl (OR = 0.09 [CI, 0.01–0.75]; p = 0.026) and lack of prophylaxis during labour (OR = 9.50 [CI, 1.59–56.66]; p = 0.013) were identified as significant risk factors associated with MTCT. 
 
 Conclusions: The PMTCT programme at Levai Mbatha CHC is effective in reducing the MTCT of HIV. Lack of ART prophylaxis and low CD4 count were the significant determinants of MTCT in the study.
 
 (Full text of the research articles are available online at www.medpharm.tandfonline.com/ojfp)
 
 S Afr Fam Pract 2017; DOI: 10.1080/20786190.2016.1254933

Qualitative Cytomegalovirus Polymerase Chain Reaction From Gastrointestinal Specimens for Diagnosis of Tissue Invasive Disease

Qualitative Cytomegalovirus Polymerase Chain Reaction From Gastrointestinal Specimens for Diagnosis of Tissue Invasive Disease

Detection of sunblotch viroid from fruits of avocado cultivar ‘Hass’ using fluorescence-based qualitative real-time polymerase chain reaction

Detection of sunblotch viroid from fruits of avocado cultivar ‘Hass’ using fluorescence-based qualitative real-time polymerase chain reaction

Study of genetic translocations in children with acute lymphoblastic leukemia using qualitative Multiplex Reverse Transcriptase Polymerase chain reaction.

e21006 Background: Despite the high rate of cure, ALL is one of the leading causes of death in children. The chromosomal translocations which have a therapeutic and prognostic significance ETV6-RUN...

PCR-based assay to detect sheeppox virus in ocular, nasal, and rectal swabs from infected Moroccan sheep

Sheeppox is now enzootic in Morocco. The development of a reliable method for rapid diagnosis of the disease is a central part of any control strategy. The aim of this study is to determine the diagnostic value of a variety of clinical samples such as ovine nasal, ocular or rectal swabs for the detection of sheeppox virus (SPPV) by qualitative conventional polymerase chain reaction (PCR), using a single pair of primers targeting the inverted terminal repeats of the SPPV InS-1 strain, a virulent field isolate. Swab and blood samples were collected from forty animals naturally infected with SPPV who had clinical signs of sheeppox. All animals tested PCR-positive for SPPV. Positive results were obtained infrequently with blood samples, whereas swab samples from at least two sites (nasal, ocular, rectal) were positive per evaluated animal. These results indicate that swab samples are suitable for quantitative molecular SPPV diagnosis. PCR product sequences obtained from all types of sheep samples proved to be identical to the corresponding regions of sheeppox virus strain Romania 65.

Event-Specific Qualitative and Quantitative Detection in Transgenic Soybean OsDREB3 Based on the 5′ Flanking Sequence

With the development of genetically modified organisms, labeling regulations have been introduced that require appropriate detection methods. Event-specific qualitative and quantitative polymerase chain reaction (PCR) detection methods have become the internationally agreed state-of-the art. Using adaptor PCR, we analyzed the flanking sequences of exogenous integrant in transgenic soybean OsDREB3, which has resistance genes. In this study 5′ region flanking sequences of exogenous gene were identified in the soybean OsDREB3 genome, which was integrated in chromosome 1 with an additional 394 bp insertion between soybean genomic DNA and exogenous gene. Based on these inserts and flanking sequences, the event-specific qualitative and quantitative PCR system was established for this line. In the conventional qualitative PCR assay, the event-specific primers designed were confirmed to be specific and the limit of detection (LOD) was 0.1%. In the quantitative real-time PCR assay, the LOD and the limit of quantity were 10 and 100 haploid genome copies, respectively. The goodness of the linearity and high efficiency of the PCR reaction indicated the utility of the established PCR system. This study provides two reliable methods and information for detection, identification, and quantification of the presence of non-authorized transgenic soybean OsDREB3.

Polyomavirus BK Infection in End-stage Renal Disease: Analysis of Viral Replication in Patients on Hemodialysis or Peritoneal Dialysis

Patients in end-stage renal disease undergoing renal replacement treatment (ESRD-RRT) are considered immunocompromised. The hemodialysis (HD) or peritoneal dialysis (PD) procedures seem to produce alterations of the immune status. Interest in immunosuppression has increased due to the poliomavirus BK (BKV) infection. Our study evaluated the prevalence of BKV infection in ESRD-RRT patients and viral replication on HD or PD. From 2006 to 2011 we selected 58 patients (34 males) in ESRD-RRT for inclusion in our study. BKV replication was evaluated by qualitative real-time polymerase chain reaction. In ESRD-RRT patients, the prevalence of BKV replication on plasma was 21%. We identified two groups of patients according to the dialysis procedure: 36 patients on HD (HD group) and 22 on PD (PD group). BKV replication in the HD group was 33% (12 of 36) versus 0% (0 of 22) in the PD group. Different age, number of months on RRT, and preserved diuresis was observed in the HD versus PD groups. With our results we can speculate that BKV infection in ESRD-RRT patients is linked to factors involved in the uremia-related immune dysfunction but also to specific mechanisms related to the different RRTs. PD is an option that could be associated with a better transplant outcome for patients undergoing kidney transplantation.

Vitamin D deficiency: Correlation to interleukin-17, interleukin-23 and PIIINP in hepatitis C virus genotype 4

To assess vitamin D (Vit D) abnormalities in hepatitis C infected patients and their relationship with interleukin (IL)-17, IL-23 and N-terminal propeptide of type III pro-collagen (PIIINP) as immune response mediators. The study was conducted on 50 Egyptian patients (36 male, 14 female) with hepatitis C virus (HCV) infection, who visited the Hepatology Outpatient Clinic in the Endemic Disease Hospital at Cairo University. Patients were compared with 25 age- and sex-matched healthy individuals. Inclusion criteria were based on a history of liver disease with HCV genotype 4 (HCV-4) infection (as new patients or under follow-up). Based on ultrasonography, patients were classified into four subgroups; 14 with bright hepatomegaly; 11 with perihepatic fibrosis; 11 with hepatic cirrhosis; and 14 with cirrhosis and hepatocellular carcinoma (HCC). Total Vit D (i.e., 25-OH-Vit D) and active Vit D [i.e., 1,25-(OH)₂-Vit D] assays were carried out using commercial kits. IL-17, IL-23 and PIIINP levels were assayed using enzyme linked immunosorbent assay kits, while HCV virus was measured by quantitative and qualitative polymerase chain reaction. Levels of Vit D and its active form were significantly lower in advanced liver disease (hepatic cirrhosis and/or carcinoma) patients, compared to those with bright hepatomegaly and perihepatic fibrosis. IL-17, IL-23 and PIIINP levels were markedly increased in HCV patients and correlated with the progression of hepatic damage. The decrease in Vit D and active Vit D was concomitant with an increase in viral load, as well as levels of IL-17, IL-23 and PIIINP among all subgroups of HCV-infected patients, compared to normal healthy controls. A significant negative correlation was evident between active Vit D and each of IL-17, IL-23 and PIIINP (r = -0.679, -0.801 and -0.920 at P < 0.001, respectively). HCV-infected men and women showed no differences with respect to Vit D levels. The viral load was negatively correlated with Vit D and active Vit D (r = -0.084 and -0.846 at P < 0.001, respectively), and positively correlated with IL-17, IL-23 and PIIINP (r = 0.951, 0.922 and 0.94 at P < 0.001, respectively). Whether the deficiency in Vit D was related to HCV-induced chronic liver disease or was a predisposing factor for a higher viral load remains to be elucidated. The negative correlations between Vit D and IL-17, IL-23 and PIIINP highlight their involvement in the immune response in patients with HCV-4-related liver diseases in Egypt.

Gene expression signatures and ex vivo drug sensitivity profiles in children with acute lymphoblastic leukemia

Causes of treatment failure in acute lymphoblastic leukemia (ALL) are still poorly understood. Microarray technology gives new possibilities for the analysis of the biology of leukemias. We hypothesize that drug sensitivity in pediatric ALL is driven by specific molecular mechanisms that correlate with gene expression profiles assessed by microarray analysis. The aim of the study was to determine the ex vivo resistance profiles of 20 antileukemic drugs and gene expression profiles, with relation to response to initial therapy. Lymphoblasts were analyzed after bone marrow biopsy was obtained from 56 patients. The profile of in vitro resistance to drugs was determined in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT) cytotoxicity assay. High-quality total RNA was prepared and hybridized to oligonucleotide arrays HG-U133A 2.0 Chip (Affymetrix). The expression of selected genes was tested by qualitative reverse transcription polymerase chain reaction (qRT-PCR). The exposure of leukemic blasts to drugs initiates a complex cellular response, which reflects global changes in gene expression. Changes in the expression of several genes are highly correlated with drug resistance.

Association between VDAC1 mRNA expression and intracellular ATP levels of cultured L-02 hepatocytes during hexavalent chromium toxicity

One way in which xenobiotics induce apoptotic cell death is to alter the selective permeability of the intracellular voltage-dependent anion channel (VDAC1) in the mitochondrial membrane. In this study, we explored the association between VDAC1 mRNA expression and mitochondrial function during hexavalent chromium compounds [Cr(VI)] treatment. Cultured L-02 hepatocytes were treated with 2, 4, 8, 16, or 32 μmol/L Cr(VI) for 12, 24, or 36 h. Expression of VDAC1 mRNA was measured by qualitative reverse transcription polymerase chain reaction (RT-PCR), whereas intracellular adenosine triphosphate (ATP) levels were determined by an ATP-specific bioluminescence assay. Over this range of Cr(VI) concentrations, average VDAC1 mRNA expression decreased by 84% after 12 h treatment and by 40% after 24 h of treatment, but it increased 2.33-fold at 36 h when compared with the control cultures. Treatment with Cr(VI) disrupted cellular metabolism as evidenced by changes in ATP levels. Cr(VI) treatment caused ATP levels to increase at 12 h, decrease at 24 h, and increase again at 36 h, resulting in a slant V-shaped curve. Correlation analysis revealed a moderate negative relationship between VDAC1 mRNA expression and intracellular ATP levels during Cr(VI) treatment (r = -0.557, P < 0.05). The negative association seemed to be more obvious in 32 μmol/L Cr(VI) group. Based on these results, heavy metal toxicity may induce over-expression of VDAC1 mRNA, which causes a decrease in ATP levels. Key words : Heavy metal toxicity, VDAC1 mRNA expression, ATP, relationship.

Congenital cytomegalovirus infection: the impact of cerebral cortical malformations

Cytomegalovirus has been suggested to have a teratogenous influence during the migration of neural cells from the ventricular zones to the cortex during the gestational period. The aim of this study was to investigate the prevalence of congenital cytomegalovirus infections in a cohort of children with neurological disability and cerebral cortical malformations recognized by neuroimaging. Twenty-six children with neurological disability and cerebral cortical malformations were investigated retrospectively for congenital cytomegalovirus infection by analysing the dried blood spot samples for cytomegalovirus deoxynucleic acid using qualitative polymerase chain reaction. CMV DNA in the dried blood spot samples was found in four out of 26 children. Two of these four had severe disabilities with mental retardation, autism, spastic cerebral palsy, epilepsy and deafness. A third child had epilepsy and unilateral cerebral palsy, while the fourth had a mild motor coordination dysfunction and hearing deficit. In our study, the number of congenital cytomegalovirus infections in children with cerebral cortical malformations was higher (4/26) than expected with reference to the birth prevalence (0.2-0.5%) of congenital cytomegalovirus infection in Sweden. We thus conclude that congenital cytomegalovirus infection should be considered in children with cortical malformations of unknown origin.