Host genetic variants associated with COVID-19 reconsidered in a Slovak cohort

We present the results of an association study involving hospitalized coronavirus disease 2019 (COVID-19) patients with a clinical background during the 3rd pandemic wave of COVID-19 in Slovakia. Seventeen single nucleotide variants (SNVs) in the eleven most relevant genes, according to the COVID-19 Host Genetics Initiative, were investigated. Our study confirms the validity of the influence of LZTFL1 and 2'-5'-oligoadenylate synthetase (OAS)1/OAS3 genetic variants on the severity of COVID-19. For two LZTFL1 SNVs in complete linkage disequilibrium, rs17713054 and rs73064425, the odds ratios of baseline allelic associations and logistic regressions (LR) adjusted for age and sex ranged in the four tested designs from 2.04 to 2.41 and from 2.05 to 3.98, respectively. The OAS1/OAS3 haplotype 'gttg' carrying a functional allele G of splice-acceptor variant rs10774671 manifested its protective function in the Delta pandemic wave. Significant baseline allelic associations of two DPP9 variants in all tested designs and two IFNAR2 variants in the Omicron pandemic wave were not confirmed by adjusted LR. Nevertheless, adjusted LR showed significant associations of NOTCH4 rs3131294 and TYK2 rs2304256 variants with severity of COVID-19. Hospitalized patients' reported comorbidities were not correlated with genetic variants, except for obesity, smoking (IFNAR2), and hypertension (NOTCH4). The results of our study suggest that host genetic variations have an impact on the severity and duration of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Considering the differences in allelic associations between pandemic waves, they support the hypothesis that every new SARS-CoV-2 variant may modify the host immune response by reconfiguring involved pathways.

Comparison of pulsed and continuous electromagnetic field generated by WPT system on human dermal and neural cells

In recent decades, we have seen significant technical progress in the modern world, leading to the widespread use of telecommunications systems, electrical appliances, and wireless technologies. These devices generate electromagnetic radiation (EMR) and electromagnetic fields (EMF) most often in the extremely low frequency or radio-frequency range. Therefore, they were included in the group of environmental risk factors that affect the human body and health on a daily basis. In this study, we tested the effect of exposure EMF generated by a new prototype wireless charging system on four human cell lines (normal cell lines-HDFa, NHA; tumor cell lines-SH-SY5Y, T98G). We tested different operating parameters of the wireless power transfer (WPT) device (87-207 kHz, 1.01-1.05 kW, 1.3-1.7 mT) at different exposure times (pulsed 6 × 10 min; continuous 1 × 60 min). We observed the effect of EMF on cell morphology and cytoskeletal changes, cell viability and mitotic activity, cytotoxicity, genotoxicity, and oxidative stress. The results of our study did not show any negative effect of the generated EMF on either normal cells or tumor cell lines. However, in order to be able to estimate the risk, further population and epidemiological studies are needed, which would reveal the clinical consequences of EMF impact.

Modelling Duchenne muscular dystrophy in vitro with newly generated, blood cell-derived induced pluripotent stem cell line ORIONi003-A

Here, we present newly derived in vitro model for modeling Duchenne muscular dystrophy. Our new cell line was derived by reprogramming of peripheral blood mononuclear cells (isolated from blood from pediatric patient) with Sendai virus encoding Yamanaka factors. Derived iPS cells are capable to differentiate in vitro into three germ layers as verified by immunocytochemistry. When differentiated in special medium, our iPSc formed spontaneously beating cardiomyocytes. As cardiomyopathy is the main clinical complication in patients with Duchenne muscular dystrophy, the cell line bearing the dystrophin gene mutation might be of interest to the research community.

Underexplored reciprocity between genome-wide methylation status and long non-coding RNA expression reflected in breast cancer research: potential impacts for the disease management in the framework of 3P medicine

Breast cancer (BC) is the most common female malignancy reaching a pandemic scale worldwide. A comprehensive interplay between genetic alterations and shifted epigenetic regions synergistically leads to disease development and progression into metastatic BC. DNA and histones methylations, as the most studied epigenetic modifications, represent frequent and early events in the process of carcinogenesis. To this end, long non-coding RNAs (lncRNAs) are recognized as potent epigenetic modulators in pathomechanisms of BC by contributing to the regulation of DNA, RNA, and histones' methylation. In turn, the methylation status of DNA, RNA, and histones can affect the level of lncRNAs expression demonstrating the reciprocity of mechanisms involved. Furthermore, lncRNAs might undergo methylation in response to actual medical conditions such as tumor development and treated malignancies. The reciprocity between genome-wide methylation status and long non-coding RNA expression levels in BC remains largely unexplored. Since the bio/medical research in the area is, per evidence, strongly fragmented, the relevance of this reciprocity for BC development and progression has not yet been systematically analyzed. Contextually, the article aims at:consolidating the accumulated knowledge on both-the genome-wide methylation status and corresponding lncRNA expression patterns in BC andhighlighting the potential benefits of this consolidated multi-professional approach for advanced BC management. Based on a big data analysis and machine learning for individualized data interpretation, the proposed approach demonstrates a great potential to promote predictive diagnostics and targeted prevention in the cost-effective primary healthcare (sub-optimal health conditions and protection against the health-to-disease transition) as well as advanced treatment algorithms tailored to the individualized patient profiles in secondary BC care (effective protection against metastatic disease). Clinically relevant examples are provided, including mitochondrial health control and epigenetic regulatory mechanisms involved.

MiR-126 and miR-146a as markers of type 2 diabetes mellitus: a pilot study

INTRODUCTION

Despite known risk factors for developing type 2 diabetes mellitus (T2D), the research community still tries to discover new markers that would widen our diagnostic and therapeutic approach to diabetes. Therefore, research on microRNA (miR) in diabetes thrives. This study aimed to assess the utility of miR-126, miR-146a, and miR-375 as novel diagnostic markers for T2D.

METHODS

We examined relative quantities of miR-126, miR-146a, and miR-375 in the serum of patients with established type 2 diabetes mellitus (n = 68) and compared these with a control group (n = 29). We also undertook a ROC analysis of significantly changed miR to examine their use as a diagnostic test.

RESULTS

MiR-126 (p < 0.0001) and miR-146a (p = 0.0005) showed a statistically significant reduction in patients with type 2 diabetes mellitus. MiR-126 also proved to be an exceptional diagnostic test in our study cohort, with high sensitivity (91 %) and specificity (97 %). We did not find any difference in our study groups' relative quantities of miR-375.

CONCLUSION

The study proved a statistically significant reduction of miR-126 and miR-146a in patients with T2D (Tab. 4, Fig. 6, Ref. 51). Text in PDF www.elis.sk Keywords: microRNA, epigenetics, genomics, type 2 diabetes mellitus, miR-126, miR-146a and miR-375.

Comparison of the methods for isolation and detection of SARS-CoV-2 RNA in municipal wastewater

Introduction

Coronavirus SARS-CoV-2 is a causative agent responsible for the current global pandemic situation known as COVID-19. Clinical manifestations of COVID-19 include a wide range of symptoms from mild (i.e., cough, fever, dyspnea) to severe pneumonia-like respiratory symptoms. SARS-CoV-2 has been demonstrated to be detectable in the stool of COVID-19 patients. Waste-based epidemiology (WBE) has been shown as a promising approach for early detection and monitoring of SARS-CoV-2 in the local population performed via collection, isolation, and detection of viral pathogens from environmental sources.

Methods

In order to select the optimal protocol for monitoring the COVID-19 epidemiological situation in region Turiec, Slovakia, we (1) compared methods for SARS-CoV-2 separation and isolation, including virus precipitation by polyethylene glycol (PEG), virus purification via ultrafiltration (Vivaspin®) and subsequent isolation by NucleoSpin RNA Virus kit (Macherey-Nagel), and direct isolation from wastewater (Zymo Environ Water RNA Kit); (2) evaluated the impact of water freezing on SARS- CoV-2 separation, isolation, and detection; (3) evaluated the role of wastewater filtration on virus stability; and (4) determined appropriate methods including reverse transcription-droplet digital PCR (RT-ddPCR) and real-time quantitative polymerase chain reaction (RT-qPCR) (targeting the same genes, i.e., RdRp and gene E) for quantitative detection of SARS-CoV-2 in wastewater samples.

Results

(1) Usage of Zymo Environ Water RNA Kit provided superior quality of isolated RNA in comparison with both ultracentrifugation and PEG precipitation. (2) Freezing of wastewater samples significantly reduces the RNA yield. (3) Filtering is counterproductive when Zymo Environ Water RNA Kit is used. (4) According to the specificity and sensitivity, the RT-ddPCR outperforms RT-qPCR.

Discussion

The results of our study suggest that WBE is a valuable early warning alert and represents a non-invasive approach to monitor viral pathogens, thus protects public health on a regional and national level. In addition, we have shown that the sensitivity of testing the samples with a nearer detection limit can be improved by selecting the appropriate combination of enrichment, isolation, and detection methods.

Sensitive SARS-CoV-2 detection, air travel Covid-19 testing, variant determination and fast direct PCR detection, using ddPCR and RT-qPCR methods

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) monitoring in air traffic is important in the prevention of the virus spreading from abroad. The gold standard for SARS-CoV-2 detection is RT-qPCR; however, for early and low viral load detection, a much more sensitive method, such as droplet digital PCR (ddPCR), is required. Our first step was to developed both, ddPCR and RT-qPCR methods, for sensitive SARS-CoV-2 detection. Analysis of ten swab/saliva samples of five Covid-19 patients in different stages of disease showed positivity in 6/10 samples with RT-qPCR and 9/10 with ddPCR. We also used our RT-qPCR method for SARS-CoV-2 detection without the need of RNA extraction, obtaining results in 90-120 minutes. We analyzed 116 self-collected saliva samples from passengers and airport staff arriving from abroad. All samples were negative by RT-qPCR, while 1 was positive, using ddPCR. Lastly, we developed ddPCR assays for SARS-CoV-2 variants identification (alpha, beta, gamma, delta/kappa) that are more economically advantageous when compared to NGS. Our findings demonstrated that saliva samples can be stored at ambient temperature, as we did not observe any significant difference between a fresh sample and the same sample after 24 hours (p = 0.23), hence, saliva collection is the optimal route for sampling airplane passengers. Our results also showed that droplet digital PCR is a more suitable method for detecting virus from saliva, compared to RT-qPCR. Keywords: COVID-19; RT-PCR; ddPCR; SARS-CoV-2; nasopharyngeal swab; saliva.

Circulating metabolites in the early stage of breast cancer were not related to cancer stage or subtypes but associated with ki67 level. Promising statistical discrimination from controls

It was documented that the presence of malignancy in an organism causes metabolomic alterations in blood plasma which applies also to breast cancer. Breast cancer is a heterogeneous disease and there are only limited known relations of plasma metabolomic signatures with the tumour characteristics in early BC and knowing them would be of great advantage in noninvasive diagnostics. In this study, we focused on the metabolic alterations in early BC in blood plasma with the aim to identify metabolomic characteristics of BC subtypes. We used 50 early BC patients (FIGO stage I and II), where no additional metabolomic changes from metastatically changed remote organs were to be expected. We compared plasma levels of metabolites against controls and among various molecular and histological BC subtypes. BC patients showed decreased plasma levels of branched-chain amino acids BCAAs (and related keto-acids), histidine pyruvate and alanine balanced with an increased level of 3-hydroxybutyrate. The levels of circulating metabolites were not related to BC molecular subtypes (luminal A/luminal B), histological finding or grade, eventually stage, which indicate that in early BC, the BC patients share common metabolomics fingerprint in blood plasma independent of grade, stage or molecular subtype of BC. We observed statistically significant correlations between tumour proliferation marker Ki-67 level and circulating metabolites: alanine, citrate, tyrosine, glutamine, histidine and proline. This may point out the metabolites those levels could be associated with tumour growth, and conversely, the rate of tumour proliferation could be potentially estimated from plasma metabolites. When analyzing metabolomic changes in BC, we concluded that some of them could be associated with the metabolomic features of cancer cells, but the other observed alterations in blood plasma are the results of the complex mutual biochemical pathways in the comprehensive inter-organ metabolic exchange and communication. In the end, statistical discrimination against controls performed with AUC >0.91 showed the very promising potential of plasma metabolomics in the search for biomarkers for oncologic diseases.

Persistence of Metabolomic Changes in Patients during Post-COVID Phase: A Prospective, Observational Study

Several relatively recently published studies have shown changes in plasma metabolites in various viral diseases such as Zika, Dengue, RSV or SARS-CoV-1. The aim of this study was to analyze the metabolome profile of patients during acute COVID-19 approximately one month after the acute infection and to compare these results with healthy (SARS-CoV-2-negative) controls. The metabolome analysis was performed by NMR spectroscopy from the peripheral blood of patients and controls. The blood samples were collected on 3 different occasions (at admission, during hospitalization and on control visit after discharge from the hospital). When comparing sample groups (based on the date of acquisition) to controls, there is an indicative shift in metabolomics features based on the time passed after the first sample was taken towards controls. Based on the random forest algorithm, there is a strong discriminatory predictive value between controls and different sample groups (AUC equals 1 for controls versus samples taken at admission, Mathew correlation coefficient equals 1). Significant metabolomic changes persist in patients more than a month after acute SARS-CoV-2 infection. The random forest algorithm shows very strong discrimination (almost ideal) when comparing metabolite levels of patients in two various stages of disease and during the recovery period compared to SARS-CoV-2-negative controls.

In vitro modeling of amyotrophic lateral sclerosis with induced pluripotent stem cell technology-derived cell line ORIONi002-A

We present here a new iPS cell line for modeling sporadic form of ALS. Cell line was generated by reprogramming skin fibroblasts isolated with explant culture technology from skin biopsy, donated by ALS patient. For reprogramming, polycistronic self-replicating RNA vector was used and derived iPS cells were characterized by immunocytochemistry and FACS (pluripotent factors expression), karyotyping, STR fingerprinting analysis and in vitro differentiation assay. New cell line showed normal (46, XY) karyotype and differentiated in vitro into cells from three germ layers. STR analysis proved the origin and originality of the cell line.

Establishment of PANDA - a new human pancreatic ductal adenocarcinoma cell line with 3D cell culture technology

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive type of malignancy with one of the worst prognoses amongst any type of cancer. Surgery is applicable only to the limited number of patients with locally resectable tumors and currently represents the only curative treatment option. Treatment with chemotherapy and radiotherapy can only extend patient survival. Despite advances in conventional therapies, the five-year survival of PDAC remained largely unchanged. New in vitro and in vivo models are therefore urgently needed to investigate this type of cancer. Here, we present the establishment and characterization of a novel pancreatic cancer cell line, isolated from a patient with PDAC. Cell line abbreviated as PANDA (PANncreatic Ductal Adenocarcinoma) was established with an optimized 3D culture protocol published previously by our group. The new cancer cell line "PANDA" represents a novel in vitro approach for PDAC cancer research and new therapy testing.

Metabolomic profiling of blood plasma of patients with lung cancer and malignant tumors with metastasis in the lungs showed similar features and promising statistical discrimination against controls

Targeting metabolomic pathways is a promising strategy for cancer treatment. Alterations in the metabolomic state have also an epigenetic impact, making the metabolomic studies even more interesting. We explored metabolomic changes in the blood plasma of patients with primary and secondary lung cancer and tried to explore their origin. We also applied a discrimination algorithm to the data. In the study, blood samples from 132 patients with primary lung cancer, 47 with secondary lung cancer, and 77 subjectively healthy subjects without any cancer history were used. The samples were measured by NMR spectroscopy. PCA and PLS-DA analyses did not distinguish between patients with primary and secondary lung tumors. Accordingly, no significantly changed levels of plasmatic metabolites were found between these groups. When comparing with healthy controls, significantly increased glucose, citrate, acetate, 3-hydroxybutyrate, and creatinine balanced with decreased pyruvate, lactate, alanine, tyrosine, and tryptophan were found as a common feature of both groups. Metabolomic analysis of blood plasma showed considerable proximity of patients with primary and secondary lung cancer. The changes observed can be partially explained as cancer-derived and also as changes showing ischemic nature. Random Forrest discrimination based on the relative concentration of metabolites in blood plasma performed very promising with AUC of 0.95 against controls; however noticeable parts of differencing metabolites are overlapping with those observed after ischemic injury in other studies.

Diagnostic Potential of MicroRNAs as Biomarkers in the Detection of Preeclampsia

Preeclampsia is a multisystemic disorder that occurs in 5-8% of pregnant women and remains a leading cause of both maternal and fetal morbidity and mortality. The disease is characterized by the abnormal vascular response to placentation, but the exact pathophysiology and pathogenesis of preeclampsia remain unknown. Risk factors for preeclampsia include increased maternal age, obesity, multiple gestations, and a history of preeclampsia. Several studies have suggested that altered expression of some microRNAs (miRNAs) in placental tissue, and maternal circulation, may be associated with several types of pregnancy complications such as preeclampsia, preterm birth, and spontaneous abortion. It is assumed that these miRNAs play an important role in various cellular processes important for maintaining a healthy pregnancy, including promoting angiogenesis and the differentiation of trophoblast cells. In this review, we discuss the role of miRNAs as potential biomarkers of preeclampsia.

Methylation of MMP2, TIMP2, MMP9 and TIMP1 in abdominal aortic aneurysm

OBJECTIVES

Abdominal aortic aneurysm (AAA) and its complications are among the most serious cardiovascular diseases and its occurrence has risen sharply in recent years. The aim of this pilot study is to explore the relationship between the methylation of matrix metalloproteinases and tissue inhibitors of the metalloproteinases genes' promoter region, and abdominal aortic aneurysm (AAA) through the detection of the methylation status of MMP2, TIMP2, TIMP1, and MMP9 genes in peripheral blood.

METHODS

The study included 43 males with verified AAA (case group) and 34 healthy males (control group). The methylation status of the genes' promoter region was detected by methylation-specific polymerase chain reaction (MS-PCR).

RESULTS

In adominal aortic aneurysm patients, the methylation ratio of MMP2 gene was positive in 9.3 % (4 cases), 2.3 % (1 case) had methylated TIMP2 gene, 7.0 % (3 cases) had methylated TIMP1 gene, while the methylation ratio of MMP9 gene was positive in 93.0 % (40 cases). In the control group, MMP2 gene was found to be methylated in 5.9 % (2 cases), 5.9 % of cases had methylated TIMP2 and TIMP1 genes (2 cases), and MMP9 gene was found to be methylated in 91.2 % (31 cases).

CONCLUSION

In our pilot study, we found no association between DNA methylation of gelatinases and their tissue inhibitors, and the development of an abdominal aortic aneurysm (Tab. 2, Fig. 1, Ref. 27).

NMR plasma metabolomics study of patients overcoming acute myocardial infarction: in the first 12 h after onset of chest pain with statistical discrimination towards metabolomic biomarkers

Acute myocardial infarction (AMI) is one of the leading causes of death among adults in older age. Understanding mechanisms how organism responds to ischemia is essential for the ischemic patient's prevention and treatment. Despite the great prevalence and incidence only a small number of studies utilize a metabolomic approach to describe AMI condition. Recent studies have shown the impact of metabolites on epigenetic changes, in these studies plasma metabolites were related to neurological outcome of the patients making metabolomic studies increasingly interesting. The aim of this study was to describe metabolomic response of an organism to ischemic stress through the changes in energetic metabolites and aminoacids in blood plasma in patients overcoming acute myocardial infarction. Blood plasma from patients in the first 12 h after onset of chest pain was collected and compared with volunteers without any history of ischemic diseases via NMR spectroscopy. Lowered plasma levels of pyruvate, alanine, glutamine and neurotransmitter precursors tyrosine and tryptophan were found. Further, we observed increased plasma levels of 3-hydroxybutyrate and acetoacetate in balance with decreased level of lipoproteins fraction, suggesting the ongoing ketonic state of an organism. Discriminatory analysis showed very promising performance where compounds: lipoproteins, alanine, pyruvate, glutamine, tryptophan and 3-hydroxybutyrate were of the highest discriminatory power with feasibility of successful statistical discrimination.

Generation of ORIONi001-A induced pluripotent stem cell line for in vitro modeling of sporadic form of amyotrophic lateral sclerosis

We generated new in vitro model for sporadic form of amyotrophic lateral sclerosis by reprogramming isolated skin fibroblasts into iPSCs. Fibroblasts were reprogrammed with commercially available synthetic polycistronic, self-replicating RNA vector. As verified by FISH, an early passages of a new iPSC line showed mosaic karyotype (cells with normal and abnormal karyotype 46,XY,t(2;14)(q13;p12) were present), while late passages contained only cells with abnormal karyotype. New iPSCs differentiated into all three germ layers and formed a teratoma in nude mice. Our iPSC line represents a new model for therapy testing and drug development in the field of ALS research.

Common gene haplotypes of gelatinases and their tissue inhibitors in abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) involves complex dynamic remodeling processes in the aortic wall. Gelatinases (MMP2 and MMP9) and their respective tissue inhibitors (TIMP1 and TIMP2) play a crucial role during extracellular matrix (ECM) turnover in aortic tissue. In this study we characterized associations between the haplotypes of genes encoding gelatinase/inhibitor pairs and pathways involved in AAA, a total of 100 AAA patients and 192 controls were enrolled. For males, a significant decrease in the distribution of the minor G allele of the TIMP2 rs8082025 was observed in AAA patients (p = 0.01, 23.1% controls vs. 13.1% AAA). In addition, in males, the major TIMP2 GA haplotype was associated with AAA (86.9% AAA vs. 76.9% control; p = 0.009, OR = 1.997), whereas the TIMP2 GG haplotype (7.7% AAA vs. 13.9% control) was associated with protection against AAA (p = 0.046, OR = 0.518). The minor GAGC MMP9 haplotype was related to AAA for all study subjects as well as the males only subset (p = 0.011, OR = 2.202 and p = 0.025, OR = 2.156, respectively). Small differences in the distribution of gene haplotypes could be associated with different levels of gene expression and in turn influence gelatinases activity in AAA.

Association between interleukin-18 variants and prostate cancer in Slovak population

Interleukin-18 (IL-18), pro-inflammatory cytokine, plays important role in antitumor immunity. Polymorphisms in the IL-18 gene may lead to its altered production/activity and such modulate susceptibility to prostate cancer. The aim of this study was to evaluate the relationship between the -607 and +105 polymorphisms in the IL-18 gene and the risk of prostate cancer development and progression in Slovak population. The study was performed using 425 patients with prostate cancer, 270 patients with benign prostatic hyperplasia (BHP) and 263 healthy male controls. The statistically significant association of the -607 AC genotype (OR = 2.24; p < 0.001), CC genotype (OR = 1.86; p = 0.006), as well as C allele (OR = 1.27; p = 0.033) with the higher risk of prostate cancer development was observed. No association of the IL-18 -607 polymorphism and BHP was detected. The subset analysis revealed the significant association of the -607 AC genotype (OR = 2.01; p = 0.008) with development of higher-grade carcinomas (Gleason score ≥7) and the strong association of the -607 AC genotype (OR = 3.11; p < 0.001), CC genotype (OR = 2.96; p < 0.001) as well as C allele (OR = 1.51; p = 0.003) with the higher risk of prostate cancer development in the group of patients with PSA < 10 ng/ml. The -607 AC genotype was also connected with significantly higher IL-18 plasma concentrations. No association between the IL-18 +105 polymorphism and prostate cancer was observed. The analysis of the distribution of the -607 and +105 haplotypes showed significant association of the - 607 C/ + 105 A and - 607 C/ + 105 C haplotypes with the risk of prostate cancer. This study found that the IL-18 -607 promoter polymorphism could contribute to prostate cancer development in Slovak population. Its presence was also associated with development of higher-grade carcinomas and therefore may influences the prognosis and aggressiveness of the disease.

Circulating tumor cells in lung carcinogenesis: minireview

Metastasis development causes death in over 90% of cancer patients, and understanding the underlying biological features has long been hindered by difficulties in studying the widespread cancerous lesions and the absence of reliable methods of isolating and detecting viable metastatic cells during disease progression. These problems have an adverse impact on developing new agents capable of blocking cancer spread. Circulating tumor cells (CTCs) have a crucial role in carcinogenesis, and this review presents advanced understanding of the characteristics of CTCs and CTC cluster metastatic properties. CTC analysis could well be more valuable for the biomarker profile than tissue biopsies, and herein we highlight current research findings which have the potential to improve clinical management of lung cancer patients. We also discuss problems in CTCs and CTC cluster biology, the limitations of detection methods and possible future diagnostic and therapeutic approaches for the study of circulating cells.

Transplantation of Human-Induced Pluripotent Stem Cell-Derived Neural Precursors into Early-Stage Zebrafish Embryos

Induced pluripotent stem cells (iPS cells) generated from somatic cells through reprogramming hold great promises for regenerative medicine. However, how reprogrammed cells survive, behave in vivo, and interact with host cells after transplantation still remains to be addressed. There is a significant need for animal models that allow in vivo tracking of transplanted cells in real time. In this regard, the zebrafish, a tropical freshwater fish, provides significant advantage as it is optically transparent and can be imaged in high resolution using confocal microscopy. The principal goal of this study was to optimize the protocol for successful short-term and immunosuppression-free transplantation of human iPS cell-derived neural progenitor cells into zebrafish and to test their ability to differentiate in this animal model. To address this aim, we isolated human iPS cell-derived neural progenitor cells from human fibroblasts and grafted them into (a) early (blastocyst)-stage wild-type AB zebrafish embryos or (b) 3-day-old Tg(gfap:GFP) zebrafish embryos (intracranial injection). We found that transplanted human neuronal progenitor cells can be effectively grafted and that they differentiate and survive in zebrafish for more than 2 weeks, validating the model as an ideal platform for in vivo screening experiments. We conclude that zebrafish provides an excellent model for studying iPS cell-derived cells in vivo.

miR-21, miR-221 and miR-150 Are Deregulated in Peripheral Blood of Patients with Colorectal Cancer

The Aim of this study was to evaluate the expression levels of miR-21, miR-221, miR-150, let-7a and miR-126a in peripheral blood of 71 patients with colorectal cancer and 80 matched healthy control individuals. We determined expression levels of these microRNAs in peripheral blood samples and used small nucleolar RNA (RNU48) as an internal control. Expression levels of miR-21 (p<0.0001) and miR-221 (p<0.0001) were significantly higher, whereas expression levels of miR-150 (p=0.0054) were significantly lower in the blood samples of patients with colorectal cancer in comparison to the control group. The combination of these three microRNAs enabled us to distinguish patients with colorectal cancer from healthy donors with a sensitivity of 80% and specificity of 74% (p<0.0001). We did not observe any correlation of the studied microRNAs with clinicopathological features of colorectal cancer, indicating that expression of these microRNAs is more likely related to the host response to the tumour than the tumour itself.

Microfluidic profiling of apoptosis-related genes after treatment with BH3-mimetic agents in astrocyte and glioblastoma cell lines

Glioblastoma (GB) is the most frequent and biologically the most aggressive primary brain tumor in adults. Standard treatment for newly diagnosed GB consists of surgical resection, radiotherapy and chemotherapy. Resistance to therapy is a major obstacle, even with optimal treatment with a survival median of only 12-15 months. The heterogeneity and treatment response of GB makes this tumor type a challenging area of research. The aim of our study was to study the response of normal human astrocyte (HA) and human GB (T98G) cell lines to apoptosis inhibitors in vitro. ABT-737 is an inhibitor of anti-apoptotic proteins Bcl-2, Bcl-xL, Bcl-w, while MIM-1 is an Mcl-1 protein inhibitor. The viability of the cells was assayed biochemically using the cytotoxic methyl thiazolyl tetrazolium (MTT) assay. Changes in the expression of apoptosis-associated genes (n=93) in two human brain cell lines after treatment with the apoptosis inhibitors ABT-737 and MIM-1 (individually), between the apoptosis inhibitor treated group and the control group, were determined using a commercially pre-designed microfluidic array. Significant changes in apoptotic gene expression with more than a 2.0-fold difference in their expression levels were obtained in both cell lines; the most altered genes were in the HA cell line after MIM-1 treatment (n=42). These results contribute to the importance of apoptosis in normal and cancerous brain tissues and provide information on the effect of apoptosis inhibitors on cell viability and gene expression. Despite extensive investigations, a cure for GB is currently not available. The identification of an apoptotic gene panel and determining the sensitivity of normal and GB brain cells to individual apoptosis inhibitors could help to improve clinical practice and increase our understanding of brain tumor cell metabolism and apoptosis inhibitors in GB cells and astrocytes. Recognizing expression changes in pro-apoptotic and anti-apoptotic genes could contribute to the development of new treatments.

News in Pathogenesis of Chronic Venous Insufficiency

This review article is concentrating on the news in the pathophysiology of chronic venous insufficiency (CVD). Despite ongoing progress in understanding the molecular aspects of CVD the exact mechanism of its development remains unclear. Many different factors may play role in the pathogenesis of CVD, including changes in hydrostatic pressure, valvular incompetence, increased capillary permeability, endothelial dysfunction, activation of leukocytes, deep venous obstruction, capillary microthrombosis, ineffective function of calf muscle pump, biochemical and structural changes in the vessel wall, extracellular matrix alteration, and several other mechanisms. A better understanding of the pathophysiology is an important step in the finding of new potential treatment.

Associations of CYP1A2 Polymorphisms with the Risk Haplotypes in Lung Cancer in the Slovak Population

Phase I enzymes, including cytochrome P450, family 1, subfamily A, and polypeptide 2 (CYP1A2), are involved in the activation of carcinogens to reactive intermediates that are capable of binding covalently to DNA to form DNA adducts, potentially initiating the carcinogenic process. The aim of present study was to investigate the association of CYP1A2 gene polymorphisms and haplotypes with lung cancer risk. A case-control study was carried out on 105 lung cancer patients and 189 controls. To investigate three CYP1A2 polymorphisms: rs2472299, rs2470890, rs11072508 we used a high resolution melting analysis. We found significant allele associations (rs2470890 and rs2422299) with lung cancer risk. We searched for meaningful associations for all variants in the dominant, recessive, and additive genetic models. Genotype associations in the recessive model were of marginal significance for the same single nucleotide polymorphisms. A haplotype analysis included five variants with the frequency higher than 1 %. The haplotype "acc", present with the highest frequency, was associated with increased lung cancer risk (38.7 % vs. 31.5 %; OR 1.38; 95 %CI 0.95-2.01). On the contrary, rare haplotype "gtc" was significantly associated with decreased lung cancer risk in the Slovak population. In conclusion, the present study identified the risk alleles and haploid genotype associations of the CYP1A2 gene in lung cancer.

DNA methylation and detection of cervical cancer and precancerous lesions using molecular methods

Cervical cancer is the third most common cancer disease affecting the female population, and a key factor in the development of the disease is the human papillomavirus infection (HPV). The disease is also impacted by epigenetic changes such as DNA methylation, which causes activation or exclusion of certain genes. The aim of our review is to summarize and compare the most common molecular methods for detection of methylated promoter regions in biomarkers occurring in cervical carcinoma and also show the importance of connections of HR-HPV testing with methylation analysis in patients with cervical intraepithelial neoplasia. Insight into genetic and epigenetic alterations associated with cervical cancer development can offer opportunities for the molecular biomarkers that can be useful for screening, diagnosis, and also as new ways of treatment of cervical cancer precursor lesions.

DNA repair genes polymorphism and lung cancer risk with the emphasis to sex differences

Polymorphisms in nucleotide and base excision repair genes are associated with the variability in the risk of developing lung cancer. In the present study, we investigated the polymorphisms of following selected DNA repair genes: XPC (Lys939Gln), XPD (Lys751Gln), hOGG1 (Ser326Cys) and XRCC1 (Arg399Gln), and the risks they present towards the development of lung cancer with the emphasis to gender differences within the Slovak population. We analyzed 761 individuals comprising 382 patients with diagnosed lung cancer and 379 healthy controls. Genotypes were determined by polymerase chain reaction/restriction fragment length polymorphism method. We found out statistically significant increased risk for lung cancer development between genders. Female carrying XPC Gln/Gln, XPC Lys/Gln+Gln/Gln and XRCC1 Arg/Gln, XRCC1 Arg/Gln+Gln/Gln genotypes had significantly increased risk of lung cancer corresponding to OR = 2.06; p = 0.04, OR = 1.66; p = 0.04 and OR = 1.62; p = 0.04, OR = 1.69; p = 0.02 respectively. In total, significantly increased risk of developing lung cancer was found in the following combinations of genotypes: XPD Lys/Gln+XPC Lys/Lys (OR = 1.62; p = 0.04), XRCC1 Gln/Gln+hOGG1 Ser/Ser (OR = 2.14; p = 0.02). After stratification for genders, the following combinations of genotype were found to be significant in male: XPD Lys/Gln+XPC Lys/Lys (OR = 1.87; p = 0.03), XRCC1 Arg/Gln+XPC Lys/Lys (OR = 4.52; p = 0.0007), XRCC1 Arg/Gln+XPC Lys/Gln (OR = 5.44; p < 0.0001). In female, different combinations of the following genotypes were found to be significant: XRCC1 Arg/Gln+hOGG1 Ser/Ser (OR = 1.98; p = 0.04), XRCC1 Gln/Gln+hOGG1 Ser/Ser (OR = 3.75; p = 0.02), XRCC1 Arg/Gln+XPC Lys/Gln (OR = 2.40; p = 0.04), XRCC1 Arg/Gln+XPC Gln/Gln (OR = 3.03; p = 0.04). We found out decreased cancer risk in genotype combinations between female patients and healthy controls: XPD Lys/Lys+XPC Lys/Gln (OR = 0.45; p = 0.02), XPD Lys/Gln+XPC Lys/Lys (OR = 0.32; p = 0.005), XPD Lys/Gln+XPC Lys/Gln (OR = 0.48; p = 0.02). Our results did not show any difference between pooled smokers and non-smokers in observed gene polymorphisms in the association to the lung cancer risk. However, gender stratification indicated the possible effect of heterozygous constitution of hOGG1 gene (Ser/Cys) on lung cancer risk in female non-smokers (OR = 0.20; p = 0.01) and heterozygous constitution of XPC gene (Lys/Gln) in male smokers (OR = 2.70; p = 0.01).

Chromosomal damage among medical staff occupationally exposed to volatile anesthetics, antineoplastic drugs, and formaldehyde

OBJECTIVES

Structural chromosomal aberrations in blood lymphocytes represent a biomarker for cellular damage caused by genotoxic carcinogens and are an indicator of increased cancer risk. We evaluated the association between frequencies of total chromosomal aberrations, chromatid- and chromosome-type aberrations, and occupational exposures to volatile anesthetics, antineoplastic agents, and formaldehyde among 601 medical professionals.

METHODS

Chromosomal damage among exposed individuals and unexposed controls was determined by conventional cytogenetic analysis. We used binary logistic regression to evaluate the effects of workplace exposures and major confounders on chromosomal damage.

RESULTS

Significantly higher frequencies of total chromosomal, chromatid-type and chromosome-type aberrations were observed among subjects occupationally exposed to volatile anesthetics, antineoplastic agents, and formaldehyde compared to age- and sex-matched controls (P<0.0001). The risk of an increased frequency of chromosomal aberrations was associated with exposure to anesthetics [odds ratio (OR) 3.9, 95% confidence interval (95% CI) 2.7-5.8], cytostatics (OR 2.7, 95% CI 1.9-3.9), and formaldehyde (OR 1.7, 95% CI 1.1-2.7). No other covariate contributed significantly to the model. Chromatid- and chromosome-type aberrations were associated with exposure to anesthetics and cytostatics without any contribution of other variables. Stratified data analysis showed the risk of increased chromosomal aberrations among non-smoking female nurses and physicians exposed to anesthetics, cytostatics and, partially, formaldehyde. Chromatid and chromosome exchanges were significantly higher in the exposed groups than among controls.

CONCLUSION

Our findings indicate that the presence of genotoxic compounds in operating rooms, oncological units, and pathological departments results in a significant increase of chromosomal damage (impair of chromosomal integrity) among medical workers employed in these facilities.

Relation between expression pattern of p53 and survivin in cutaneous basal cell carcinomas

Background

The tumor suppressor gene p53 is a key regulator of cell division and/or apoptosis. Survivin is a multifunctional member of the inhibitor of apoptosis family. Survivin and p53 represent diametrically opposed signals that influence the apoptotic pathway.

Material/Methods

To determine the role of p53 and survivin in basal cell carcinoma (BCC), we evaluated the expression pattern of both proteins with regard to the percentage of positively immunostained tumor cells, the intensity of staining, and subcellular localization among 31 subjects with BCC.

Results

Overexpression of p53 protein was found in 28 of 31 cases (90.3%), whereas survivin accumulation was seen in 27 (87.1%). For p53, moderate and/or strong immunoreactivity was seen in 20 of 28 cases (71.4%), and 26 of 28 cases (92.9%) showed more than 25% reactive tumor cells. Nuclear p53 staining was detected in 23 of 28 cases (82.1%), whereas combined nuclear and cytoplasmic localization was found in only 5 of 28 cases (17.9%). Survivin revealed mild intensity of immuno-reaction in 22 of 27 cases (71%), and 25 of 27 cases (92.6%) showed less than 25% labeled tumor cells. Combined nuclear and cytoplasmic survivin localization was present in 26 of 27 cases (96.3%). Statistically significant differences were detected in the assessed expression parameters between those proteins.

Conclusions

Our results suggest that overexpression of wild type p53 protein may suppress the expression of survivin and its antiapoptotic activity in BCC cells.

Survivin: a promising biomarker in breast carcinoma

The antiapoptotic protein survivin can be detected in most types of malignant tumors, but it is rarely expressed in corresponding normal adult tissues. Therefore, survivin appears to represent a promising diagnostic biomarker. We examined survivin expression in 13 cases of normal breast tissue, 38 cases of fibroadenomas and 80 cases of breast carcinomas by immunohistochemical staining using anti-survivin antibody (DAKO, Clone 12C4). In each section, the intensity of staining, percentage of labeled cells, and the subcellular location of survivin antigen were assessed. Survivin was detected in 4/13 cases of normal breast tissue (30.7%), in 28/38 cases of fibroadenomas (73.7%), and in 67/80 cases of carcinomas (83.8%). Normal breast tissue showed cytoplasmic positivity only. In fibroadenomas, 19 cases (50.0%) revealed cytoplasmic reaction, and in 9 cases (23.7%), small foci of cells with combined nuclear and cytoplasmic location were identified. In carcinomas, cytoplasmic staining was found in 12/80 cases (15.0%), nuclear staining in 10/80 cases (12.5%), and combined cytoplasmic and nuclear staining in 45/80 cases (56.3%). Subcellular location of survivin between benign and malignant lesions revealed significant differences (p<0,001). Our findings point at practical use of survivin detection. We confirm the importance of nuclear staining of survivin antigen in breast carcinoma, which seems to be a notable diagnostic marker for estimation of the degree of neoplasia.

Lung cancer incidence and survival in chromium exposed individuals with respect to expression of anti-apoptotic protein survivin and tumor suppressor P53 protein

OBJECTIVE

Workers chronically exposed to hexavalent chromium have elevated risk of lung cancer. Our study investigates the incidence of lung cancer types, age at onset of the disease, and survival time among chromium exposed workers with respect to the expression of anti-apoptotic p53 and pro-apoptotic survivin proteins.

MATERIAL AND METHODS

67 chromium exposed workers and 104 male controls diagnosed with lung cancer were analyzed. The mean exposure time among workers was 16.7 ±10.0(SD) years (range 1- 41 years). To investigate the possible regulation of survivin by p53 we examined the expression of both proteins using immohistochemical visualization.

RESULTS

Chromium exposure significantly decreases the age of onset of the disease by 3.5 years (62.2 ±9.1 in the exposed group vs. 65.7 ±10.5 years in controls; P=0.018). Small cell lung carcinoma (SCLC) amounted for 25.4% of all cases in chromium exposed workers and for 16.3% in non-exposed individuals. The mean survival time in the exposed group was 9.0 ±12.7 vs. 12.1 ±21.9 months in controls, but this difference was not significant. Survivin was predominantly expressed in both cell nucleus and cytoplasm, whereas p53 was expressed in the nucleus. There was a negative correlation between survivin and p53 expression. A decreased intensity of expression and fewer cells positive for survivin was detected in SCLC compared with other types of lung cancer. p53 was expressed in 94.1% and survivin in 79.6% of the samples analyzed.

CONCLUSION

The study calls attention to decreased expression of survivin, as opposed to p53, in small cell lung carcinoma.

Gene polymorphisms of biotransforming enzymes (GSTs) and their association with lung cancer in the Slovakian population

Objective

The aim of present study was to present the results of a case-control study focused on genetic polymorphisms of selected Phase II metabolizing enzymes (GSTM1, T1, and P1) and to investigate the association of these polymorphisms with lung cancer risk in the Slovakian population.

Material and methods

The study encompassed 160 lung cancer cases and 220 controls. DNA was extracted from peripheral blood leukocytes, and the polymorphisms of GSTM1, GSTT1 and GSTP1 enzymes were determined by PCR-based methods. We determined the genotype distribution of all these genes and their combinations. The association between specific genotypes and the development of lung cancer were examined using logistic regression analysis to calculate odds ratios (OR) and 95% confidence intervals (CI).

Results

We found that the GSTM1 null genotype (OR = 1.6; 95% CI = 1.03-2.4; χ² = 4.08, and P = 0.04) was associated with elevated risk. A significant correlation also was found for the combined genotypes of GSTM1 null and GSTP1 Ile/Val and Val/Val (OR = 2.01; 95% CI = 1.1-6.1; χ² = 3.6, and P = 0.02) and GSTM1 null and GSTT1 positive (OR = 2.00; 95% CI = 1.2-3.2; χ² = 7.3, and P = 0.006).

Conclusions

We conclude that the genotype of metabolizing enzymes and allelic combinations underscore the risk for lung cancer. Individual risk assessment may be further improved by increasing the number of polymorphisms studied and combining them with the traditional epidemiological risk factor.

Provocation of aspiration reflexes and their effects on the pattern of cough and reflex apnea in cats

Aspiration reflexes (AspRs) manifesting as reflex spasmodic inspirations and their effects on motor pattern of tracheobronchial cough and reflex apnea were studied on 22 spontaneously breathing pentobarbitone-anesthetized cats. AspRs induced during cough inspiration enhanced peak inspiratory (P<0.01) and expiratory (P<0.02) esophageal pressures, amplitudes of diaphragm (P<0.01) and abdominal muscles (P<0.05) EMG activity, and prolonged the entire expiratory period (P<0.01) and total cycle duration (P<0.05) of cough. Transient inhibitions and splits of cough expiration frequently occurred with AspR within active cough expiratory period; however, cough spatiotemporal characteristics were not altered significantly. Sub-threshold nasopharyngeal stimulation failing to provoke AspR had no significant effects on coughing. Hering-Breuer inflation apnea was moderately prolonged by AspRs (20%; P<0.05), unlike the apnea produced by continual mechanical laryngeal stimulation. AspRs are inducible during tested behaviors interacting with their motor pattern. Central mechanisms involving pulmonary stretch receptor stimulation is suggested for modulation of cough and inflation apnea by AspR.

Excitability and rhythmicity of tracheobronchial cough is altered by aspiration reflex in cats

Effects of nasopharyngeal stimulation on excitability and rhythmicity of mechanically induced tracheobronchial cough were examined on 18 pentobarbitone anesthetized cats. After the 17.2+/-2.4 aspiration reflexes (AspRs), tracheobronchial stimulation evoked lower number of coughs (P<0.05) with longer latency to the diaphragm activation (P<0.02), compared to control. AspRs induced within "inter-cough" periods (motor quiescence between individual coughs; 3.3 AspRs per period) reduced cough number by 50% (P<0.01), shortened cough-related abdominal activity (P<0.02), prolonged inter-cough period (P<0.02), and the total cough cycle duration (P<0.05). Cough efforts occurred irregularly with very variable "inter-cough" distances and total cough cycle durations. The subthreshold nasopharyngeal stimulation (failing to evoke AspR) did not affect rhythmic coughing. AspRs induced during persisting post-stimulation coughs did not significantly reduce their number. Excitability and rhythmicity of mechanically induced tracheobronchial cough can be reduced by AspRs, but not by subthreshold nasopharyngeal stimulation. The suppressive effect of spasmodic inspirations on chronic cough is suggested.

Human lung cancer and hexavalent chromium exposure

OBJECTIVE

Workers chronically exposed to hexavalent chromium have higher incidence of lung cancer. Our study investigates incidence of lung cancer types, age at onset of the disease and survival time among chromium exposed workers (smelters, tapers, crane operators) in comparison to non-exposed persons.

METHODS

64 chromium exposed workers and 104 male controls with diagnosed lung cancer were analysed. The average exposure time among workers was 16.71 +/- 10.02 (S.D.) years (range 1- 41 years).

RESULTS

Chromium exposure significantly decreases the age at the onset of the disease by 3.51 years (62.20 +/- 9.08 years in exposed group and 65.71 +/- 10.50 years in control; P=0.018). Small cell lung carcinoma (SCLC) forms 25.0 % of all cases in chromium exposed workers and 16.34% in non exposed individuals. No correlation was found between the age at the diseases onset and time of exposure. The mean survival time in exposed group was 9.03 +/- 12.73 month, in control 12.14 +/- 21.94 month, but this difference was not significant (P=0.473).

CONCLUSION

Occupational exposure to chromium was identified as an important risk factor of lung cancer, decreasing the age at the diseases onset. Higher percentage of SCLC was found in chromium exposed individuals.

Medullary raphe midline is involved in production of expulsive expirations in anesthetized rabbits

Effects of kainic acid lesions in the medullary raphe midline on reflex expirations induced mechanically from the trachea were examined. Spontaneously breathing rabbits were anesthetized by ketamine and xylazine i.m., followed by pentobarbitone i.v. Excitatory neurotoxin kainic acid (2 mg/ml in artificial CSF, total volume of 55-100 nl) was pressure microinjected into the medullary midline, rostral to the obex (2 microinjections at 2 different depths). The lesion (mostly affected the obscurus and magnus raphe nuclei) reduced the number of reflex expirations by 80% and expiratory amplitudes of esophageal pressure, abdominal EMG moving averages, and abdominal EMG powers by 71%, 62%, and 57%, respectively (in all cases P<0.05). The duration of abdominal activity in post-lesion responses was not altered. Control microinjections of artificial CSF had no effect on the reflex responses. We conclude that in rabbits, the medullary raphe nuclei participate in the control of expiratory expulsions originating from the trachea.

Chromosomal damage and polymorphisms of DNA repair genes XRCC1 and XRCC3 in workers exposed to chromium

OBJECTIVES

Welders, chronically exposed to hexavalent chromium, may exhibit disturbances in chromosomal integrity. Our study investigates chromosomal damage related to chromium exposure, considering the role of polymorphisms in relevant DNA repair genes.

METHODS

39 male welders exposed to chromium for 10.2+/-1.67 years and 31 male controls were assayed for structural chromosomal aberrations (conventional cytogenetic analysis). DNA repair gene polymorphisms were determined by Real-Time allelic discrimination assay.

RESULTS

Total chromosomal aberrations were moderately, but statistically not significant, higher in exposed individuals (1.96%) than in controls (1.55%). Chromosomal type breaks were almost two-fold higher in exposed than in control individuals. The highest frequency of total chromosomal aberrations was recorded in individuals with homozygous variant Gln/Gln cariers (2.14%) in XRCC1* Arg-399Gln and the lowest in those with the wild-type Arg/Arg cariers (1.33%). Polymorphisms in XRCC3 gene did not modulate the frequencies of CAs, CTAs and CSAs.

CONCLUSIONS

Understanding the effects of chromium on chromosomal integrity in relation to individual susceptibility may be a basis for preventive measures in working process.

Chromosomal aberrations in tire plant workers and interaction with polymorphisms of biotransformation and DNA repair genes

We evaluated chromosomal aberrations in lymphocytes of 177 workers exposed to xenobiotics in a tire plant and in 172 controls, in relation to their genetic background. Nine polymorphisms in genes encoding biotransformation enzymes and nine polymorphisms in genes involved in main DNA repair pathways were investigated for possible modulation of chromosomal damage. Chromosomal aberration frequencies were the highest among exposed smokers and the lowest in non-smoking unexposed individuals (2.5+/-1.8% vs. 1.7+/-1.2%, respectively). The differences between groups (ANOVA) were borderline significant (F=2.6, P=0.055). Chromosomal aberrations were higher in subjects with GSTT1-null (2.4+/-1.7%) than in those with GSTT1-plus genotype (1.8+/-1.4%; F=7.2, P=0.008). Considering individual groups, this association was significant in smoking exposed workers (F=4.4, P=0.040). Individuals with low activity EPHX1 genotype exhibited significantly higher chromosomal aberrations (2.3+/-1.6%) in comparison with those bearing medium (1.7+/-1.2%) and high activity genotype (1.5+/-1.2%; F=4.7, P=0.010). Both chromatid- and chromosome-type aberration frequencies were mainly affected by exposure and smoking status. Binary logistic regression analysis revealed that frequencies of chromatid-type aberrations were modulated by NBS1 Glu185Gln (OR 4.26, 95%CI 1.38-13.14, P=0.012), and to a moderate extent, by XPD Lys751Gln (OR 0.16, 95%CI 0.02-1.25, P=0.081) polymorphisms. Chromosome-type aberrations were lowest in individuals bearing the EPHX1 genotype conferring the high activity (OR 0.38, 95%CI 0.15-0.98, P=0.045). Present results show that exposed individuals in the tire production, who smoke, exhibit higher chromosomal aberrations frequencies, and the extent of chromosomal damage may additionally be modified by relevant polymorphisms.

Short reflex expirations (expiration reflexes) induced by mechanical stimulation of the trachea in anesthetized cats

Fifty spontaneously breathing pentobarbital-anesthetized cats were used to determine the incidence rate and parameters of short reflex expirations induced by mechanical stimulation of the tracheal mucosa (ERt). The mechanical stimuli evoked coughs; in addition, 67.6% of the stimulation trials began with ERt. The expiration reflex mechanically induced from the glottis (ERg) was also analyzed (99.5% incidence, p < 0.001 compared to the incidence of ERt). We found that the amplitudes of abdominal, laryngeal abductor posterior cricoarytenoid, and laryngeal adductor thyroarytenoid electromyograms (EMG) were significantly enhanced in ERg relative to ERt. Peak intrathoracic pressure (esophageal or intra-pleural pressure) was higher during ERg than ERt. The interval between the peak in EMG activity of the posterior cricoarytenoid muscle and that of the EMG of abdominal muscles was lower in ERt compared to ERg. The duration of thyroarytenoid EMG activity associated with ERt was shorter than that in ERg. All other temporal features of the pattern of abdominal, posterior cricoarytenoid, and thyroarytenoid muscles EMGs were equivalent in ERt and ERg.In an additional 8 cats, the effect of codeine administered via the vertebral artery was tested. Codeine, in a dose (0.03 mg/kg) that markedly suppressed cough did not significantly alter either the incidence rate or magnitudes of ERt.In the anesthetized cat the ERt induced by mechanical stimulation of the trachea was similar to the ERg from the glottis. These two reflex responses differ substantially only in the frequency of occurrence in response to mechanical stimulus and in the intensity of motor output.

Brainstem regions involved in the expiration reflex. A c-fos study in anesthetized cats

Expression of the immediate-early gene c-fos, a marker of neuronal activation, was employed to localize brainstem neuronal populations functionally related to the expiration reflex (ER). Twelve spontaneously breathing, non-decerebrate, pentobarbital anesthetized cats were used. The level of Fos-like immunoreactivity (FLI) in 6 animals with repetitive ERs mechanically induced from the glottis (296+/-9 ERs) was compared to FLI in 6 control non-stimulated cats. Respiratory rate, arterial blood pressure, and end tidal CO(2) concentration remained stable during the experiment. In the medulla, increased FLI was found in the region of nucleus tractus solitarii (p<0.001), in the ventrolateral medulla along with the lateral tegmental field (p<0.01), and in the vestibular nuclei (p<0.01). In the pons, increased FLI was detected in the caudal extensions of the lateral parabrachial and Kölliker-Fuse nuclei (p<0.05). Within the rostral mesencephalon, FLI was enhanced in the midline area (p<0.05). A lower level of ER-related FLI compared to control animals was detected in the pontine raphe region (p<0.05) and the lateral division of mesencephalic periaqueductal gray (p<0.05). The results suggest that the ER is coordinated by a complex long loop of medullary-pontine-mesencephalic neuronal circuits, some of which may differ from those of other respiratory reflexes. The FLI related to the expulsive behavior ER differs from that induced by laryngeal stimulation and laryngeal adductor responses, particularly in ventrolateral medulla and mesencephalon.

Brainstem circuitry of tracheal-bronchial cough: c-fos study in anesthetized cats

The c-fos gene expression method was used to localize brainstem neurons functionally related to the tracheal-bronchial cough on 13 spontaneously breathing, pentobarbitone anesthetized cats. The level of Fos-like immunoreactivity (FLI) in 6 animals with repetitive coughs (170+/-12) induced by mechanical stimulation of the tracheobronchial mucosa was compared to FLI in 7 control non-stimulated cats. Thirty-four nuclei were compared for the number of labeled cells. Enhanced cough FLI was found bilaterally at following brainstem structures, as compared to controls: In the medulla, FLI was increased in the medial, interstitial and ventrolateral subnuclei of the solitary tract (p < 0.02), in the retroambigual nucleus of the caudal medulla (p < 0.05), in the ambigual, paraambigual and retrofacial nuclei of the rostral medulla along with the lateral reticular nuclei, the ventrolateral reticular tegmental field (p < 0.05), and the raphe nuclei (p < 0.05). In pons, increased FLI was detected in the lateral parabrachial and Kölliker-Fuse nuclei (p < 0.01), in the posteroventral cochlear nuclei (p < 0.01), and the raphe midline (p < 0.05). Within the mesencephalon cough-related FLI was enhanced at the rostral midline area (p < 0.05), but a decrease was found at its caudal part in the periaqueductal gray (p < 0.02). Results of this study suggest a large medullary - pontine - mesencephalic neuronal circuit involved in the control of the tracheal-bronchial cough in cats.

Swelling over the face: infantile cortical hyperostosis

Swelling over the face in infancy may be caused by parotitis, abscess glandulae parotis, osteomyelitis, purulent lymph node, bone tumor or by infantile cortical hyperostosis (the Caffey-Silverman syndrome). The case report shows the typical clinical, laboratory and radiographic changes seen in infantile cortical hyperostosis. It is a benign condition, often disappearing spontaneously but also cases of recurrence are known. The knowledge of the typical signs and laboratory findings enables the determination of a quick and reliable diagnosis.