Polychlorinated biphenyls in sediments of the Tam Giang-Cau Hai Lagoon, Central Vietnam

The Tam Giang-Cau Hai Lagoon, the largest in south east Asia, suffers from a great anthropogenic pressure and appears subject to a process of progressive environmental deterioration. To establish causes, history and trends of lagoon contamination, sediment samples representing three major parts of the systems were sampled and analysed for porosity, organic carbon, total nitrogen, delta(13)C, grain size, radiotracers and PCBs. PCB surficial concentrations range from 10.2 to 24.5 microg kg(-1), and maximum values are close to NOAA ERL guidelines. The downcore distribution of PCBs shows two well defined peaks in the core from Tam Giang (25.5 and 16.2 microg kg(-1)), whereas the sediment from Cau Hai is characterised by a maximum at the surface. Therefore, present trends indicate that contamination is still increasing or slightly decreasing. The prevailing congeners are 3-CB and 4-CB, hence recent PCBs appear to be mostly originated by Aroclor 1016- and 1242-like mixtures, with some samples influenced also by Aroclor 1248. Present sources seem to be similar everywhere and probably they are widespread all over the territory of the Thua Thien-Hue province.

GnRH antagonists in ovarian stimulation for ICSI with oocyte restriction: a matched, controlled study

Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.

P2Y2 receptor up-regulation induced by guanosine or UTP in rat brain cultured astrocytes

Among P2 metabotropic ATP receptors, P2Y2 subtype seems to be peculiar as its upregulation triggers important biological events in different cells types. In non-stimulated cells including astrocytes, P2Y2 receptors are usually expressed at levels lower than P2Y1 sites, however the promoter region of the P2Y2 receptors has not yet been studied and little is known about the mechanisms underlying the regulation of the expression of this ATP receptor. We showed that not only UTP and ATP are the most potent and naturally occurring agonist for P2Y2 sites, but also guanosine induced an up-regulation of astrocyte P2Y2 receptor mRNA evaluated by Northern blot analysis. We also focused our attention on this nucleoside since in our previous studies it was reported to be released by cultured astrocytes and to exert different neuroprotective effects. UTP and guanosine-evoked P2Y2 receptor up-regulation in rat brain cultured astrocytes was linked to an increased P2Y2-mediated intracellular calcium response, thus suggesting an increased P2Y2 activity. Actinomycin D, a RNA polymerase inhibitor, abrogated both UTP and guanosine-mediated P2Y2 up-regulation, thus indicating that de novo transcription was required. The effect of UTP and guanosine was also evaluated in astrocytes pretreated with different inhibitors of signal transduction pathways including ERK, PKC and PKA reported to be involved in the regulation of other cell surface receptor mRNAs. The results show that ERK1-2/MAPK pathway play a key role in the P2Y2 receptor up-regulation mediated by either UTP or guanosine. Moreover, our data suggest that PKA is also involved in guanosine-induced transcriptional activation of P2Y2 mRNA and that increased intracellular calcium levels and PKC activation may also mediate P2Y2 receptor up-regulation triggered by UTP. The extracellular release of ATP under physiological and pathological conditions has been widely studied. On the contrary, little is known about the release of pyrimidines and in particular of UTP. Here we show that astrocytes are able to release UTP, either at rest or during and following hypoxia/hypoglycemia obtained by submitting the cells to glucose-oxygen deprivation (OGD). Interestingly, also P2Y2 receptor mRNA increased by about two-fold the control values when the cultures were submitted to OGD. It has been recently reported that P2Y2 receptors can play a protective role in astrocytes, thus either guanosine administration or increased extracellular concentrations of guanosine and UTP reached locally following CNS injury may increase P2Y2-mediated biological events aimed at promoting a protective astrocyte response.

Multiple sclerosis: pharmacogenomics and personalised drug treatment

Multiple sclerosis (MS) is a disorder of the central nervous system with an inflammatory and a neurodegenerative component. We do not yet have a definitive therapy for MS. Attempts to develop new treatments are long and costly and should be paralleled by studies aimed at increasing the therapeutic index of the existing treatments, interferon beta and glatiramer acetate. Pharmacogenetics and pharmacogenomics may be of use in this respect though their application may not be straightforward, particularly in MS.

Prognostic factors for patients with lymphoma requiring intensive care

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Background: Prognosis of patients (pts) with hematological malignancies (HM) in the intensive care unit (ICU) seems to be improving, despite different biological behaviors and outcomes. The study of homogenous groups of pts might provide useful clinical insights. The aim of this study was to evaluate the outcomes of critically ill patients with lymphomas (CIPL). Methods: During 66 months, all consecutive CIPL admitted to an oncologic ICU were studied. Variables collected were: age, gender, performance status, type and status of lymphoma, neutropenia, infection at admission, use of mechanical ventilation (MV), the Acute Physiology and Chronic Health Evaluation (APACHE) II score, comorbidities and number of acute organ failures (AOF). Variables selected in the univariate analysis (p < 0.25) and those clinically relevant were entered in a multivariable logistic regression analysis [results expressed as odds-ratios (OR), 95% confidence interval (CI)]. The end-point was hospital mortality. Results: A total of 120 CIPL were studied. Mean age was 51 ± 20 years and 54% were males. APACHE II was 19 ± 7 points. Diagnoses were High Grade Non-Hodgkin’s Lymphoma (77.5%), Hodgkin’s disease (17.5%) and Low Grade Non-Hodgkin’s Lymphoma (5%). Reasons for ICU admission were severe sepsis (62%) and acute respiratory failure (22%). During ICU stay 90% pts received MV, 71% vasopressors and 27.5% dialysis. Twenty-three (19%) pts had neutropenia. End-of-life decisions were implemented in 31% pts and all of them died at the ICU. The ICU and hospital mortality rates were 53% and 67% respectively, with no difference among the groups of lymphomas (p = 0.877). Variables identified in the multivariate analysis were: age [OR = 1.03 (95% CI = 1.01–1.06)], male gender [3.72 (1.27–10.90)], uncontrolled disease [OR = 6.28 (1.80–21.95), for pts with newly diagnosed disease and OR = 5.33 (1.45–19.47), for those with recurrence/progression, sepsis [OR = 5.31 (1.62–17.37)] and AOF [OR = 2.35 (1.53–3.61)]. Conclusions: Higher age, male gender, the severity of organ failures, sepsis and disease status were the main adverse factors. Type of lymphoma and neutropenia had no impact in the outcome. The appropriate use of such easily available clinical characteristics may avoid forgoing intensive care for lymphoma pts with a chance of survival.

No significant financial relationships to disclose.

The contribution of epigenetic and genetic changes to predict gastrointestinal stromal tumors (GIST) behavior

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Background: To search for markers for better prognostic evaluation in patients (pts) with GIST was our goal. Loss of E-cadherin expression and/or function by hypermethylation has been correlated with increase in the invasive potential of human tumors. Recently, loss of p16INK4a expression was considered as an independent prognostic factor in pts with GIST. Methods: We investigated the methylation (MT) status for p16Ink4a and E-cadherin by the MT -specific PCR, c-KIT mutation by SSCP-sequencing, p16INK4a and cKIT expressions and KI-67 index by IHC, in 81 pts with completely ressected GIST between Jan 1990 and April 2003. Clinical data and follow-up information were obtained from medical records.A cutoff at 20% and 5% positivity was used for p16INK4a and KI-67, respectively. Univariate analysis of disease-free survival (DFS) and overall survival (OS) were performed by Kaplan Meier method with the log-rank test. Results: Median age was 55 (9–78); Male/female 42/58%; primary tumor sites were stomach (46.9%), small bowell (37.0%), colorectal (8.6%) and peritoneal (6.2%). Median tumor size was 8cm (1.2–35.0). The median follow-up was 24 months. Pts were stratified into low- (24.7%), intermediate- (37.0%) and high- (38.3%) risk pts based on tumor size and mitotic index. There was a significant correlation between risk classification and disease free survival (DFS) (p=0.023) and overall survival (OS) (p=0.010). The p16Ink4a and E-cadherin MT were observed in 19.4% and 63.3% pts, respectively. We observed loss of p16INK4a expression in 64.9% of GISTs. Overall, 78.4% had KIT mutation in exon 11 or 9. There was non-significant correlations between epigenetic alterations, cKIT mutation, p16INK4a expression, KI-67 index and survival. By analysing the three groups separately we found a significant correlation between E-cadherin MT with DFS (p<0.047) only in the intermediate risk group. Conclusion: Our results suggest that E-cadherin MT may be a helpful prognostic factor particularly in the intermediate risk group of GISTs. In contrast with previous results from the literature p16INK4a alterations had no prognostic impact in our samples.

No significant financial relationships to disclose.

Limiting the number of injected oocytes to three impairs ICSI outcomes in patients with nonobstructive azoospermia

BACKGROUND

Since March 2004, only a maximum of three oocytes were allowed to be subjected to ICSI at one time in Italy. A previous study failed to show an impact of this restriction on fresh embryo transfer outcomes. The objective of this study was to compare ICSI outcomes before and after this restriction in patients with nonobstructive azoospermia.

METHODS

Patients underwent testicular sperm extraction followed by ICSI. Biological (fertilization rate and the percentage of good-morphology zygotes and embryos) and clinical (clinical pregnancy and implantation rates) outcomes of the last 100 ICSI attempts before the restriction and outcomes of the first 100 ICSI attempts after the restriction were compared.

RESULTS

Despite comparable fertilization rates (58.8% versus 59.2%; P > 0.05), there was a significant decrease in the percentage of good-morphology zygotes (41.1% versus 88.4%; P < 0.05) and embryos (36.7% versus 74.0%; P < 0.05) in the cohort of embryos transferred, clinical pregnancy rate (22.7% versus 42.4%; P < 0.05) and cumulative pregnancy rate from fresh and frozen embryo transfers (22.7% versus 53.5%; P < 0.05) after the restriction.

CONCLUSION

The oocyte number restriction reduces dramatically the chance of achieving a clinical pregnancy in cases of nonobstructive azoospermia.

Molar tooth sign and superior vermian dysplasia: a radiological, clinical, and genetic study

We have identified a group of 13 patients with a homogeneous radiological pattern at MRI consisting of the molar tooth sign (MTS) and superior vermian dysplasia. The patients represent a relatively heterogeneous clinical group with variable severity of developmental delay, ataxia, hypotonia, and apnea. Careful examination of MRI prompted us to split our series of patients into two groups, based on IVth ventricle dilatation. In 4/13 patients the IVth ventricle was judged to be dilated and those patients were less severely affected while most clinically affected patients had a normal IVth ventricle. DNA samples of blood leukocytes from 6/13 consanguineous patients were genotyped using polymorphic markers encompassing the Joubert syndrome loci. We therefore sequenced AHI1 located in 6q23 in two patients who were homozygous at the locus and in four sporadic cases. Only one homozygous nonsense mutation was identified. Clinically, the patient exhibiting the AHI1 mutation was the most severely affected child with a profound encephalopathy, major hypotonia, ataxia, Leber congenital amaurosis, and normal IVth ventricle at the MRI. The present study suggests that the syndrome associating MTS and dysplasia of the superior vermis of the cerebellum is a clinically and genetically heterogeneous entity and that Jouberin (AHI1) mutations account for a marginal fraction of patients.

Baroreflex control of heart rate during sleep in severe obstructive sleep apnoea: effects of acute CPAP

Baroreflex control of heart rate during sleep (baroreflex sensitivity; BRS) has been shown to be depressed in obstructive sleep apnoea (OSA), and improved after treatment with continuous positive airway pressure (CPAP). Whether CPAP also acutely affects BRS during sleep in uncomplicated severe OSA is still debatable. Blood pressure was monitored during nocturnal polysomnography in 18 patients at baseline and during first-time CPAP application. Spontaneous BRS was analysed by the sequence method, and estimated as the mean sequence slope. CPAP did not acutely affect mean blood pressure or heart rate but decreased cardiovascular variability during sleep. Mean BRS increased slightly during CPAP application (from 6.5+/-2.4 to 7.5+/-2.9 ms x mmHg(-1)), mostly in response to decreasing blood pressure. The change in BRS did not correlate with changes in arterial oxygen saturation or apnoea/hypopnoea index. The small change in baroreflex control of heart rate during sleep at first application of continuous positive airway pressure in severe obstructive sleep apnoea was unrelated to the acute resolution of nocturnal hypoxaemia, and might reflect autonomic adjustments to positive intrathoracic pressure, and/or improved sleep architecture. The small increase in baroreflex control of heart rate during sleep may be of clinical relevance as it was accompanied by reduced cardiovascular variability, which is acknowledged as an independent cardiovascular risk factor.

Chlamydia pneumoniae in asymptomatic carotid atherosclerosis

We evaluated, in 415 patients with asymptomatic carotid atherosclerosis: (i) the prevalence of C. pneumoniae DNA in atherosclerotic carotid plaques and peripheral blood mononuclear cells (PBMC); (ii) the distribution of C. pneumoniae in atherosclerotic carotid plaques and PBMC from the same patients; (iii) the correlation between circulating anti-chlamydial antibodies and the presence of C. pneumoniae DNA. Overall, 160 atherosclerotic carotid plaques and 174 PBMC specimens from patients with asymptomatic carotid atherosclerosis were examined by ompA nested touchdown PCR for presence of C. pneumoniae. In addition, C. pneumoniae DNA was detected in 81 specimens of atherosclerotic carotid plaque and PBMC obtained from the same patients. C. pneumoniae DNA was found in 36.9% of atherosclerotic carotid plaques and in 40.2% of PBMC specimens examined (P=NS). With regard to 81 patients, C. pneumoniae DNA was detected in 27.2% of atherosclerotic carotid plaques and in 44.4% of PBMC specimens(P=0.05). In 18 patients, the presence of C. pneumoniae DNA in PBMC specimens and atherosclerotic carotid plaques coincided (P=0.005). No statistically significant association was found between anti-C. pneumoniae antibodies (IgG and IgA) and positive PCR results. In conclusion, our results suggest that the detection of C. pneumoniae DNA in PBMC specimens seems to be a first-choice method to identify the patients at risk for endovascular chlamydial infection.

Bradykinin stimulates cell proliferation through an extracellular-regulated kinase 1 and 2-dependent mechanism in breast cancer cells in primary culture

We have previously reported that bradykinin (BK) represents an influential mitogenic agent in normal breast glandular tissue. We here investigated the mitogenic effects and the signalling pathways of BK in primary cultured human epithelial breast cells obtained from a tumour and from the histologically proven non-malignant tissue adjacent to the tumour. BK provoked cell proliferation, increase in cytosolic calcium, activation of protein kinase C (PKC)-alpha, -beta, -delta, -epsilon and -eta and phosphorylation of the extracellular-regulated kinases 1 and 2 (ERK1/2). The following compounds blocked the proliferative effects of BK: Hyp3-BK, a B2 receptor subtype inhibitor; U73122, a phospholipase C-beta inhibitor; GF109203X, a protein kinase C (PKC) inhibitor; and PD98059, a mitogen-activated protein kinase kinase inhibitor. Gö6976, a Ca(2+)-dependent PKC inhibitor, did not have any effect. In conclusion, the mitogenic effects of BK are retained in peritumour and tumour cells; hence, it is likely that BK has an important role in cancer endorsement and progression.

Hysteroscopy may be justified after two miscarriages

BACKGROUND

Recurrent pregnancy loss is traditionally investigated after three or more consecutive pregnancy losses. Although there is a trend to start investigation after two miscarriages, data are not available to date to justify this approach. We sought to compare the frequency of uterine anomalies between women referred to hysteroscopy for repeated miscarriages after two, and three or more, miscarriages respectively.

METHODS

A retrospective analysis of acquired and congenital uterine anomalies in all patients undergoing hysteroscopy for repeated pregnancy loss at an academic and referral medical centre.

RESULTS

Hysteroscopy was performed on 165 women referred for recurrent pregnancy loss: 67 after two and 98 after three or more consecutive miscarriages. The rate of uterine anomalies did not differ significantly and was 32 versus 28% respectively.

CONCLUSIONS

Hysteroscopy may be justified following two spontaneous pregnancy losses.

Evidence for bone mass and body fat distribution relationship in postmenopausal obese women

The measurement of bone mass, a reliable predictor of osteoporotic fractures, in obese subjects has yielded conflicting results and bone mass has been reported to be elevated, normal or decreased. These observations indicate that factors other than body weight may be involved in the less risk for osteoporosis in obese subjects. In order to clarify the role of body fat distribution on bone density we studied sixty postmenopausal overweight/obese women with Body Mass Index (BMI) over 25 kg/m(2). Thirty five age-matched, nonobese postmenopausal women, served as controls. Bone mineral density (BMD) was measured at the proximal and ultradistal non dominant forearm using a double energy X-ray absorption (DEXA) apparatus. The waist/hip circumferences ratio (WHR) was used, in obese group, as an anthropometric estimation of the abdominal (WHR>0.85) to lower-extremity (WHR>0.85) fat proportion. The results were analyzed by Student t-test, ANOVA, and multiple linear regression analysis. No difference was found in BMD between obese group and controls, but a highly significant (P<0.001) positive correlation has been documented between proximal and ultradistal radius bone mineral density and waist/hip ratio in the obese group. Instead not significant correlation was found with BMI. Regional fat topography may influence the bone mass independently of total adiposity and visceral fat was the primary parameter accounting for higher bone mineral density values. These finding suggest that women with android-like obesity are protected from osteoporosis.