Influenza surveillance on ‘foie gras’ duck farms in Bulgaria, 2008–2012

Objectives

Ducks can shed and spread influenza A viruses (IAVs) while showing no disease signs. Our objective was to clarify the role of ‘foie gras’ ducks in the circulation of IAVs in Bulgaria.

Methods

Monthly avian influenza surveillance was conducted on 63 ‘foie gras’ duck farms, 52 of which were surveyed throughout the study between November 2008 and April 2012. Virologic and serologic samples were collected and tested. During this time, wild bird samples were collected at major wild bird‐resting areas near the Black Sea coast and Danube River.

Results

The study showed high isolation frequency of low‐pathogenicity avian influenza viruses. In the raising population (<75 days old), subtypes H3, H4, and H6 were detected monthly and H5 LPAIV, sporadically. Different subtypes (H1, H10, H11) were isolated from the fattening premises (75‐ to 100‐day‐old ducks), suggesting different routes of introduction. Only 6 of the 52 farms that were surveyed both virologically and serologically were influenza‐free throughout the study, possibly due to higher biosecurity measures implemented. No evidence of direct transmission of IAV from wild birds was found. Wild bird surveillance showed low isolation frequency of IAV. IAV prevalence of 0·55% for migratory ducks and 0·53% for migratory geese was estimated in November–December 2011 and January–February 2012, respectively, at two ornithologically important locations near the Black Sea coast.

Conclusions

The ‘foie gras’ duck farms in Bulgaria are an optimal niche where Eurasian‐like IAVs are maintained and reassorted unapparent to farmers and veterinarians.     

Essential role of insulin-like growth factor I receptor in insulin-induced fetal brown adipocyte differentiation

To define the specific role of IGF-I receptor (IGF-IR) in adipogenic and thermogenic differentiation of brown adipocytes during late fetal life, we have established immortalized brown adipocyte cell lines from fetuses of IGF-IR-deficient mice (IGF-IR(-/-)) as well as from wild-type mice (IGF-IR(+/+)). IGF-IR(-/-) cells showed an increased insulin sensitivity regarding insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation despite a substantial reduction in IRS-1 protein content. Furthermore, insulin-induced total and IRS-1-associated phosphatidylinositol 3-kinase activities were augmented in IGF-IR-deficient cells compared with wild-type cells. Downstream phosphatidylinositol 3-kinase activation of Akt, but not p70s6 kinase, were elicited at lower doses of insulin in IGF-IR(-/-) brown adipocytes. Activation of protein kinase Czeta by insulin was similar in both cell types as was insulin-induced glucose uptake. Treatment of wild-type brown adipocytes with insulin for 12 h up-regulated fatty acid synthase (FAS) and adipocyte determination and differentiation (ADD1/SREBP) mRNAs; this effect was impaired in the absence of IGF-IR. At the protein level, insulin increased FAS content and the amount of the mature form of adipocyte determination and differentiation (ADD1/SREBP) in the nucleus in wild-type cells, but not in IGF-IR(-/-) cells. Furthermore, 24 h of insulin stimulation induced the expression of both uncoupling protein-1 and CCAAT/enhancer-binding protein alpha (C/EBPalpha) in wild-type brown adipocytes; these effects were abolished in IGF-I-R(-/-) cells. Retrovirus-mediated reexpression of peroxisomal proliferator-activated receptor gamma (PPARgamma) in IGF-IR(-/-) brown adipocytes could overcome FAS mRNA impairment, bypassing insulin signaling. However, insulin further increased FAS mRNA expression in C/EBPalpha-IGF-IR(-/-) cells, but not in PPARgamma-IGF-IR(-/-) cells. In addition, fetal brown adipocytes lacking IGF-IR up-regulated uncoupling protein-1 expression in the absence of insulin when PPARgamma, but not C/EBPalpha, was overexpressed. These data provide strong evidence for a critical role of IGF-IR in the differentiation of the brown adipocyte phenotype in fetal life; this effect is mimicked by PPARgamma in an insulin-independent manner.     

The corticotrophin-releasing hormone test is the most reliable noninvasive method to differentiate pituitary from ectopic ACTH secretion in Cushing's syndrome

OBJECTIVE: It has been reported previously that the paired interpretation of the corticotrophin-releasing hormone (CRH) test and the 8-mg dexamethasone suppression test (HDDST) could have higher diagnostic power than any single test in the differential diagnosis of ACTH-dependent Cushing's syndrome. This finding has not been confirmed thereafter in large series. The aim of the present study has been to assess the operating characteristics of either the CRH test or the overnight HDDST and also to evaluate the potential utility of combining the interpretation of both tests in the differential diagnosis of ACTH-dependent Cushing's syndrome. DESIGN AND PATIENTS: We have reviewed the medical records of 59 consecutive cases with ACTH-dependent Cushing's syndrome: 49 patients with proven Cushing's disease (CD) and 10 patients with proven ectopic ACTH syndrome (EAS). Univariate curves of the receiver operating characteristics (ROC) have been performed to define the best cut-off values, the sensitivity and the specificity for CRH and overnight HDDST. A comparison between the areas under the ROC curves has also been performed. RESULTS: For the CRH test, the point on the ROC curve closest to 1 corresponded to a value of ACTH percentage increment of 50%[sensitivity 86% (72.6-94.8) and specificity 90% (55.5-98.3)]. The best threshold for cortisol percentage (30%) increment gave inferior results [sensitivity 61% (45.5-75.6) and specificity 70% (34.8-93.0)]. For the HDDST, the point on the ROC curve closest to 1 corresponded to a value of cortisol decrease from the baseline of 50%[sensitivity 77% (62.7-88.5), specificity 60% (26.4-87.6)]. The area under the ROC curve of the ACTH percentage increment after CRH was significantly greater than the area under the diagonal [0.9 (0.7-1.0), P= 0.0001]. Conversely, the area under the cortisol percentage decrement after dexamethasone was not different from that obtained by chance [0.7 (0.5-0.9), P= ns]. The area under the ROC curve of CRH is significantly greater than that of overnight HDDST (P = 0.03). A correct diagnosis has been achieved by the CRH test in 86.5% of cases and by the HDDST in 73% (P = 0.06). The combination of both tests has given a correct diagnosis in a significantly lower percentage of cases than the CRH test alone (69%, P= 0.04). The bilateral inferior petrosal sinus sampling (BIPSS) has been performed in 29 patients (24 CD, five EAS) who had negative imaging and/or discordant results of the noninvasive tests. Considering the criterion of a central to peripheral ACTH ratio > 3 after CRH stimulation, a correct diagnosis was achieved in all cases. CONCLUSIONS: The present data suggest that the CRH is likely to be the most reliable noninvasive diagnostic procedure for the differential diagnosis of the ACTH-dependent Cushing's syndrome. The criterion for a diagnosis of EAS is an ACTH percentage increment lower than 50%. The use of a combination of tests is not recommended because it does not add valuable information and may even impair the outcome of the CRH test. Cases with discordant results in pituitary imaging and CRH test should undergo BIPSS. The validity of this approach, which is straightforward and easily applicable in clinical practice, should be verified in larger series.     

Drug-drug interactions and the pharmacotherapy of HIV infection

Knowledge of drug-drug interactions is crucial to HIV therapeutics. Recent reports in this area include reduced atazanavir exposure with coadministration of omeprazole or rifampin; increased hepatic toxicity with coadministration of saquinavir and rifampin; reduced buprenorphine exposure with concurrent efavirenz administration; absence of clinically significant interactions of depomedroxyprogesterone with nevirapine, efavirenz, or nelfinavir; increased atazanavir and saquinavir exposure with the double-boosted regimen of atazanavir/saquinavir/ritonavir; reduced amprenavir, lopinavir, and saquinavir exposure with the addition of tipranavir/ritonavir therapy; and reduced lopinavir and amprenavir exposure with the addition of fosamprenavir or fosamprenavir/ritonavir to lopinavir/ritonavir. This article summarizes a presentation on drug-drug interactions in HIV therapeutics by Angela D. M. Kashuba, PharmD, at the International AIDS Society-USA course in Los Angeles in April 2005.     

Nosocomial infections in a neonatal intensive care unit: incidence and risk factors

BACKGROUND: Nosocomial infections (NIs) have become a matter of major concern in neonatal intensive care units (NICUs). The objectives of this study were to determine the incidence rate and the most frequent sites of infection in a Brazilian NICU from January 1999 to March 2000 and to study the risk factors for NIs. METHODS: A cohort study was carried out in which 225 neonates who remained at least 24 hours in the NICU were followed-up; neonates with NIs were identified, and the presence of risk factors was studied. Results were submitted to chi(2) distribution. RESULTS: The incidence rate and the incidence density rate were 50.7% and 62 infections per 1000 patient-days, respectively. In order of frequency, the sites of infection were: pneumonia (40.3%), primary bloodstream (16.7%), skin and soft tissue (14.9%), and meningitis (9.6%). The following risk factors were associated with NIs (P <.05): birth weight, gestational age, mechanical ventilation, total parenteral nutrition, umbilical catheter, use of antibiotics, and intubation in the delivery room. CONCLUSION: Risk factors were similar to those reported by other authors. However, incidence rates of infections in our NICU were much higher, possibly because of different methodologies and the adopted criteria for the classification of NIs.     

Lack of evidence for protease evolution in HIV-1-infected patients after 2 years of successful highly active antiretroviral therapy

The mechanisms involved in maintaining a latent replication-competent integrated human immunodeficiency virus type 1 (HIV-1) reservoir after successful highly active antiretroviral therapy (HAART) have not been fully described. The objective of this study was to assess whether low-level, persistent HIV-1 replication can be detected in the protease gene, in 10 HIV-1-infected patients who have undergone 2 years of successful HAART. Peripheral blood mononuclear cells (PBMCs) were collected from 10 HIV-1-infected patients receiving a triple-drug combination therapy (2 nucleoside analogues and 1 protease inhibitor). HIV-1 RNA levels and CD4+ and CD8+ T cell counts were longitudinally determined during a follow-up period of 108 weeks. Similarly, proviral fragments of the protease-coding region, obtained at baseline and at week 108 of HAART, were amplified by polymerase chain reaction from PBMCs, and 10-25 individual clones were sequenced for each time point. Only 1 of 271 individual protease clones showed a major resistance substitution (M46I [patient D]). Phylogenetic analysis revealed that, in all patients, the genetic distances from the deduced most recent common ancestor, in samples obtained at week 108 of HAART, were not longer than those in samples obtained at baseline. Moreover, the pattern of amino acid divergence during therapy showed an absence of positive selection in the protease-coding region. Taken together, these results show a lack of clinically relevant evolution in the protease-coding region after 2 years of successful HAART.     

Comparison of infarct size changes with delayed contrast-enhanced magnetic resonance imaging and electrocardiogram QRS scoring during the 6 months after acutely reperfused myocardial infarction

Introduction

Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium that has infracted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size.

Aim

The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases.

Methods

In 31 patients (26 men, age 56 ± 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were taken from 1 to 2 days (acute), 1 month (healing), and 6 months (chronic) after the MI. Selvester QRS scoring was used to estimate the infarct size from the ECG.

Results

The correlation values between infarct size measured by DE-MRI and QRS scoring range from 0.33 to 0.43 higher for anterior than inferior infarcts. The infarct size estimated by QRS scoring was larger (about 5% of the left ventricle) than infarct size by DE-MRI acute and 1 month, but at 6 months, there was no difference. In about half of the patients, the QRS score agreed with DE-MRI in change of infarct size from acute to 6 months.

Conclusion

In conclusion, the Selvester QRS scoring system is in half of the patients with reperfused first time MI in good accordance with DE-MRI in identifying a decrease or no change in the extent of left ventricle occupied by infarction in the acute and chronic phases.     

Rapid discrimination of early CD34+ myeloid progenitors using CD45-RA analysis

Mononuclear cells (MNC) isolated by density centrifugation of cord blood and healthy bone marrow, and of peripheral blood (PB) from patients treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF after chemotherapy, were double-stained with anti CD34 monoclonal antibody (MoAb) (8G12) versus anti CD45, CD45-RB, CD45- RO, and CD45-RA, respectively, and analyzed by flow cytometry. In all specimens, CD34+ MNC co-expressed CD45 at a low level and the expression of CD45-RB was similar or slightly higher. Most CD34+ MNC were negative for CD45-RO, a weak coexpression was only seen in some bone marrow (BM) and blood samples. In contrast, CD45-RA could subdivide the CD34+ population into fractions negative, dim (+), and normal positive (++) for these subgroups, and typical staining patterns were observed for the different sources of hematopoietic cells: in BM, most CD34+ MNC were RA++. In PB, their majority was RA++ after G-CSF but RA+ or RA- after GM-CSF. In cord blood, the hematopoietic progenitors were mainly RA-/RO-. Semisolid culture of sorted CD34+ MNC showed that clusters and dispersed (late) colony-forming unit-GM (CFU- GM) originated from 34+/RA++ cells, while the 34+/RA- MNC formed compact and multicentric, both white and red colonies derived from early progenitors. Addition of 20 ng stem cell factor per milliliter of medium containing 34+/RA- cord blood MNC led to a change of many burst- forming unit-erythrocyte (BFU-E) to CFU-mix which was not, at least to this extent, seen in blood and BM. We conclude that early myeloid CD34+ cells are 45+/RA-. Because this population excludes 34+/19+ B cells and 33+ myeloid cells, both of which are RA++, two-color flow cytometric analysis using CD34 and CD45-RA facilitates the characterization and quantification of early myeloid progenitor cells.     

Immunostaining of p53 protein in ovarian carcinoma: correlation with histopathological data and clinical outcome

Objective: The objective of this study was to analyze the incidence of immunohistochemically detectable p53 protein accumulation in epithelial ovarian carcinomas and to correlate these data with the clinical outcome so as to clarify further the role of p53 mutations in prognosis with these patients.Methods: Tumor tissues from 179 patients with epithelial ovarian carcinoma were used for immuno-histochemical analysis with monoclonal antibody DO1 and BP 53-12-1 on formalin-fixed, paraffin-embedded tissue.Results: A total of 78 cases (44%) showed positive nuclear p53 staining. The p53-positive cases were found in all histological types of epithelial ovarian tumors. p53 staining was found in tumors of all stages with a higher percentage of positive cases in stage IV ovarian carcinomas (not significant). Poorly differentiated carcinomas showed a significantly higher percentage of p53 protein expression than did highly differentiated tumors (P=0.0002). Clinical follow-up of up to 14 years (median 25 months) showed a slightly but not significantly shortened disease-free and overall survival time for patients with p53-positive epithelial ovarian carcinomas.Conclusions: We conclude from our data that p53 expression in ovarian carcinoma is associated with poor differentiation but not with the disease being in an advanced stage. There was a tendency for shortened disease-free and overall survival for patients with p53-positive tumors.     

Gene therapy blockade of dorsal striatal p11 improves motor function and dyskinesia in parkinsonian mice

Complications of dopamine replacement for Parkinson’s disease (PD) can limit therapeutic options, leading to interest in identifying novel pathways that can be exploited to improve treatment. p11 (S100A10) is a cellular scaffold protein that binds to and potentiates the activity of various ion channels and neurotransmitter receptors. We have previously reported that p11 can influence ventral striatal function in models of depression and drug addiction, and thus we hypothesized that dorsal striatal p11 might mediate motor function and drug responses in parkinsonian mice. To focally inhibit p11 expression in the dorsal striatum, we injected an adeno-associated virus (AAV) vector producing a short hairpin RNA (AAV.sh.p11). This intervention reduced the impairment in motor function on forced tasks, such as rotarod and treadmill tests, caused by substantia nigra lesioning in mice. Measures of spontaneous movement and gait in an open-field test declined as expected in control lesioned mice, whereas AAV.sh.p11 mice remained at or near normal baseline. Mice with unilateral lesions were then challenged with l-dopa (levodopa) and various dopamine receptor agonists, and resulting rotational behaviors were significantly reduced after ipsilateral inhibition of dorsal striatal p11 expression. Finally, p11 knockdown in the dorsal striatum dramatically reduced l-dopa–induced abnormal involuntary movements compared with control mice. These data indicate that focal inhibition of p11 action in the dorsal striatum could be a promising PD therapeutic target to improve motor function while reducing l-dopa–induced dyskinesias.Pharmacologic replacement of depleted dopamine is the primary therapeutic approach to treating Parkinson’s disease (PD). Although this usually improves the major motor problems of this disorder, complications of medical therapy can often limit both dosing and effectiveness. Among the most common adverse effects limiting dopamine replacement therapy for PD is the development of abnormal involuntary movements (AIMs), also known as levodopa-induced dyskinesia (LID) (1). Treatment of LID usually requires reducing the dosage of dopaminergic medications to below the threshold for major complications, although certain pharmacotherapies or surgeries can improve LID as well (1). Understanding both the anatomic location and molecular pathways underlying dyskinesia responses to dopamine replacement therapy is necessary to develop improved therapies, which can reduce motor symptoms without this debilitating problem.Previous studies have identified certain signaling pathways that may influence the development of dyskinesia. The primary site of action of l-dopa (levodopa) on PD motor symptoms after conversion to dopamine is the dorsal striatum, owing to the loss of the normal dopaminergic inputs from the substantia nigra pars compacta (2). This same region has also been shown to be responsible for motor complications of l-dopa therapy, including LID. Specifically, neurons harboring the D1 dopamine receptor appear to be primarily involved in these responses (3–5). Furthermore, other signaling pathways, including the serotonin 5-HT1B receptor, seem to modulate the response of these neurons to dopamine replacement therapy (6, 7). Nonetheless, it has been difficult to identify potential therapeutic targets that both improve motor function and reduce dyskinesia.Here we demonstrate that dorsal striatal p11 is a key regulator of dopamine responses in PD. We previously reported that p11, a small adaptor protein also known as S100A10, binds to specific serotonin receptor subtypes, including 5-HT1B (8–10). Because activation of the 5-HT1B serotonin receptor (5-HT1BR) reduces dyskinesia, and p11 binds to 5-HT1BR and potentiates 5-HT1B activity, we hypothesized that dorsal striatal p11 may influence the response to dopamine replacement therapy. We found that inhibition of p11 expression in the dorsal striatum improved motor function in parkinsonian mice. Surprisingly, blockade of dorsal striatal p11 expression profoundly inhibited dyskinesias in response to chronic l-dopa treatment, to a greater extent than pharmacologic activation of 5-HT1B in controls. This indicates that inhibition of striatal p11 is a promising potential target to block dyskinesias while improving motor function in PD, and that these effects likely occur through a mechanism other than 5-HT1B.