Exogenous retroelement integration in sperm and embryos affects preimplantation development.

Retroelement transcripts are present in male and female gametes, where they are typically regulated by methylation, noncoding RNAs and transcription factors. Such transcripts are required for occurrence of retrotransposition events, while failure of retrotransposition control may exert negative effects on cellular function and proliferation. In order to investigate the occurrence of retrotransposition events in mouse epididymal spermatozoa and to address the impact of uncontrolled retroelement RNA expression in early preimplantation embryos, we performed in vitro fertilization experiments using spermatozoa preincubated with plasmid vectors containing the human retroelements LINE-1, HERVK-10 or the mouse retroelement VL30, tagged with an enhanced green fluorescence (EGFP) gene-based cassette. Retrotransposition events in mouse spermatozoa and embryos were detected using PCR, FACS analysis and confocal microscopy. Our findings show that: (i) sperm cell incorporates exogenous retroelements and favors retrotransposition events, (ii) the inhibition of spermatozoa reverse transcriptase can decrease the retrotransposition frequency in sperm cells, (iii) spermatozoa can transfer exogenous human or mouse retroelements to the oocyte during fertilization and (iv) retroelement RNA overexpression affects embryo morphology and impairs preimplantation development. These findings suggest that the integration of exogenous retroelements in the sperm genome, as well as their transfer into the mouse oocyte, could give rise to new retrotransposition events and genetic alterations in mouse spermatozoa and embryos.

Apolipoprotein E polymorphisms and ischaemic stroke: a two-center Greek study.

BACKGROUND AND PURPOSE: Apolipropotein E(apoE) is a plasma protein exhibiting three common isoforms (E2, E3, E4). Its involvement in lipoprotein metabolism may have an impact on stroke occurrence. As results in the literature are inconclusive further studies are needed to elucidate its role. Our objective was to study the role of apoE isoforms and the interplay with environmental risk factors in patients with first ischaemic stroke occurrence in the Greek population. METHODS: Three hundred and twenty-nine patients with first-ever ischaemic stroke were included in our study. Strokes of cardioembolic origin and patients with autoimmune or prothrombotic syndromes were excluded. A control group of 361 subjects with no stroke history were also included in our study. Risk factors (hyperlipidemia, hypertension, diabetes mellitus and smoking) were assessed. ApoE alleles were determined in all subjects participating in the study. RESULTS: Genotype ε3/ε3 was found to have a protective role against stroke occurrence compared with other genotypes (odds ratio 0.674, 95% confidence interval 0.480-0.946) especially in the female patient subgroup. In multivariate analysis after adjustment for age, body mass index (BMI), hypertension, dyslipidemia, diabetes mellitus and smoking, the role of genotype was limited and outweighed by risk factors in both genders. No association between apoE alleles and BMI, cholesterol, triglycerides or high-density lipoprotein plasma levels was noted. CONCLUSIONS: Our study was indicative of a protective role of the ε3/ε3 genotype, especially in female patients. However, risk factors such as age, BMI, hypertension, dyslipidemia, diabetes mellitus and smoking have a strong impact on stroke occurrence and outweigh the protective role of the ε3/ε3 genotype.

Dramatic reduction in sperm parameters following bariatric surgery: report of two cases.

Severe obesity constitutes the main public health crisis of the industrialised world. Bariatric surgery has been proposed as the most efficient treatment of obesity. In this study, we report the potential effects of bariatric surgery on semen parameters in male partners of couples undergoing assisted reproduction. These patients had been tested in the context of infertility treatment in two consecutive cycles before and after bariatric surgery. A marked reduction in sperm parameters was observed in a period of twelve to eighteen months after surgery. This unfavourable effect had also remarkable effects on the assisted reproduction outcome, necessitating the counselling of patients before bariatric surgery.

Paraoxonase gene polymorphisms and stroke severity.

BACKGROUND: Paraoxonase (PON) is an HDL-associated enzyme that prevents low-density lipoprotein oxidation, playing a major role in the pathogenesis of atherosclerosis. PON genes polymorphisms may affect the corresponding enzyme activity. In this study, we examined the association of ischemic stroke with the three PON genes. METHODS: One hundred and seventy-eight patients hospitalized for ischemic stroke and 181 age- and sex-matched healthy controls were recruited. PON1(Q/R) 192, PON1(M/L) 55, and PON2(S/C) 311 polymorphisms were analyzed. RESULTS: The presence of the PON2 311C allele was significantly increased in patients with severe forms of ischemic stroke according to Modified Rankin Scale (P = 0.02, odds ratio = 2.215). No significant differences in genotype and allele distribution were observed between patients and controls. CONCLUSIONS: The PON2 311C allele was suggested as a possible predisposing factor for severe cases of ischemic stroke. Large-scale multicenter-controlled prospective studies are warranted to further explore the effects of PON polymorphisms on stroke susceptibility and severity.

Association of estrogen receptor-alpha gene polymorphisms with stroke risk in patients with metabolic syndrome.

OBJECTIVE: The vascular protective effects of estrogens are mediated by their binding to the two known estrogen receptors. In this study, we examine the association of stroke with two common polymorphisms of the ESR1 gene in patients with metabolic syndrome. MATERIALS AND METHODS: DNA from 130 patients hospitalized for ischemic stroke and 240 healthy controls were genotyped for ESR1 PvuII and XbaI polymorphisms. Results - Comparing female and male patients, it was found that CCGG diplotype is more frequent in male patients (P = 0.03). In addition, the AA genotype is associated with the onset of stroke at a younger age in the male patient group (P < 0.05). CONCLUSIONS: These findings suggest that PvuII and XbaI polymorphisms may affect the age at onset of the first stroke and the probability of developing cerebrovascular disease.

Astrocytoma-like multiple sclerosis.

Multiple sclerosis (MS) may sometimes mimic clinically and radiologically a brain tumor. The initial recognition of such cases is essential as it might avoid a surgical intervention and supplementary treatment. However, even in patients who underwent surgery, the appropriate preparation of the specimen is of crucial importance for the correct pathological diagnosis since tumors and non-neoplastic demyelinating lesions share some common histopathological features. We present such a case of multiple sclerosis presenting with features of an astrocytoma and was treated with surgery and additional radiotherapy.

Multifocal glioblastoma with remote cutaneous metastasis: a case report and review of the literature.

BACKGROUND: Remote extracranial mestastases of glioblastoma multiforme (GBM) are uncommon, while cutaneous seeding at a distance from the operative site appears to be even more unusual. CASE REPORT: A 63-year-old man presented with focal seizures and mental impairment. Computed tomography (CT) scan revealed a left frontoparietal mass. He underwent a gross total removal of the tumor. The tissue diagnosis was that of a GBM. Seven months later, the patient developed a left scapular subcutaneous mass. Fine-needle aspiration cytology (FNAC) was performed and the cytological findings disclosed again a GBM. One month later, after clinical deterioration, a repeat magnetic resonance imaging (MRI) scan was carried out which demonstrated two new distinct lesions in the opposite hemisphere, as in a multifocal GBM. Both lesions were biopsed under stereotactic guidance and the recurrence of GBM was confirmed. The patient died ten months after the primary diagnosis of the intracranial GBM. CONCLUSION: Improved diagnostic modalities and prolonged survival have increased the likelihood of detection of extracranial mestastases from GBM. This potential may be greater in multifocal GBM. FNA is a valuable method for the definite diagnosis of metastatic GBMs. Although several theories have been postulated, the route of remote cutaneous dissemination and the mechanism of multifocal recurrence remain to be elucidated.

Guillain-Barré syndrome in northwest Greece.

OBJECTIVES: We present the epidemiological and clinical-laboratory features of Guillain-Barré syndrome (GBS) in northwest Greece over a 9.5-year period. MATERIALS AND METHODS: We studied all the patients with GBS who were admitted to our neurology inpatient service from January 1996 to May 2005 and compared them with previously published series. RESULTS: Forty-six patients were hospitalized during this period. The average crude incidence rate was 1.22/100,000 populations per year, and males were more susceptible than females. There was a spring clustering, as 52.17% presented the syndrome during spring. The axonal type of GBS was recorded in 13.04% of the patients. The most frequent presenting symptom was dysesthetic numbness (52.17%). A large number of patients (56.52%) had up to three times the elevation of liver function values that resolved in a few weeks. Most patients had an excellent recovery and no deaths were recorded. CONCLUSIONS: In our series, there was no difference in the incidence rate and subtypes of GBS but there was a significant seasonality with spring clustering. A transient elevation of transaminases of undetermined etiology was noted in more than a half of our patients. Although seven patients (15.21%) had significant neurologic sequelae, no deaths occurred.