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The effect of a longitudinal magnetic field on the emission characteristics of a forevacuum plasma electron source based on a discharge with a hollow cathode is studied. It is shown that, starting from a certain threshold value of the induction Bc, the magnetic field leads to a decrease in the plasma concentration on the axis of the cathode cavity. With a decrease in the diameter of the cathode cavity, the threshold value of Bc increases. On the other hand, the longitudinal magnetic field makes it possible to increase the diameter of the emission chan-nel, which contributes to a significant increase in the current of electron emission from the plasma. In this case, the degree of increase in the emission current is determined by the ge-ometry of the cathode cavity and the pressure of the working gas.

Summary Background Maternal influenza immunisation can reduce morbidity and mortality associated with influenza infection in pregnant women and young infants. We aimed to determine the vaccine efficacy of maternal influenza immunisation against maternal and infant PCR-confirmed influenza, duration of protection, and the effect of gestational age at vaccination on vaccine efficacy, birth outcomes, and infant growth up to 6 months of age. Methods We did a pooled analysis of three randomised controlled trials done in Nepal (2011–2014), Mali (2011–2014), and South Africa (2011–2013). Pregnant women, gestational age 17–34 weeks in Nepal, 28 weeks or more in Mali, and 20–36 weeks in South Africa, were enrolled. Women were randomly assigned 1:1 to a study group, in which they received trivalent inactivated influenza vaccine (IIV) in all three trials, or a control group, in which they received saline placebo in Nepal and South Africa or quadrivalent meningococcal conjugate vaccine in Mali. Enrolment at all sites was complete by April 24, 2013. Infants and women were assessed for respiratory illness, and samples from those that met the case definition were tested for influenza by PCR testing. Growth measurements, including length and weight, were obtained at birth at all sites, at 24 weeks in South Africa, and at 6 months in Nepal and Mali. The three trials are registered with ClinicalTrials.gov , numbers NCT01430689 , NCT01034254 , and NCT02465190 . Findings 10 002 women and 9800 liveborn infants were included. Pooled efficacy of maternal vaccination to prevent infant PCR-confirmed influenza up to 6 months of age was 35% (95% CI 19 to 47). The pooled estimate was 56% (28 to 73) within the first 2 months of life, 39% (11 to 58) between 2 and 4 months, and 19% (–9 to 40) between 4 and 6 months. In women, from enrolment during pregnancy to the end of follow-up at 6 months postpartum, the vaccine was 50% (95% CI 32–63) efficacious against PCR-confirmed influenza. Efficacy was 42% (12 to 61) during pregnancy and 60% (36 to 75) postpartum. In women vaccinated before 29 weeks gestational age, the estimated efficacy was 30% (–2 to 52), and in women vaccinated at or after 29 weeks, efficacy was 71% (50 to 83). Efficacy was similar in infants born to mothers vaccinated before or after 29 weeks gestation (34% [95% CI 12 to 51] vs 35% [11 to 52]). There was no overall association between maternal vaccination and low birthweight, stillbirth, preterm birth, and small for gestational age. At 6 months of age, the intervention and control groups were similar in terms of underweight (weight-for-age), stunted (length-for-age), and wasted (weight-for-length). Median centile change from birth to 6 months of age was similar between the intervention and the control groups for both weight and length. Interpretation The assessment of efficacy for women vaccinated before 29 weeks gestational age might have been underpowered, because the point estimate suggests that there might be efficacy despite wide CIs. Estimates of efficacy against PCR-confirmed influenza and safety in terms of adverse birth outcomes should be incorporated into any further consideration of maternal influenza immunisation recommendations. Funding Bill & Melinda Gates Foundation.

Liver metastases are common in patients with neuroendocrine tumors (NETs), having a negative impact on disease prognosis. The options for selective therapy in patients with unresectable multiple liver metastases are limited to TACE (transarterial chemoembolization), TAE (transarterial embolization), or SIRT (selective internal radiation therapy). To explore the clinical outcome, survival and safety of these therapies in NETs patients. Retrospective case series of consecutive patients (mean age 56.6 years, 59% male) treated at two tertiary university medical centers from 2005 to 2015. Fifty-seven patients with G1, G2, and low G3 NETs with liver metastases were investigated (pancreatic NET (pNET), 24; small bowel, 16; unknown origin (UKO), 9; rectal, 3; lung, 3; and gastric, 2). Fifty-three patients underwent TACE, three patients underwent TAE, and one patient underwent SIRT. Clinical improvement and tumor response were observed in 54/57 patients (95%), together with marked decreased in tumor markers. The median time to tumor progression following the first treatment was 14 ± 16 months. The median overall survival was 22 ± 18 months, more pronounced in the pNET, followed by small bowel and UKO subgroups. There was a trend for a better survival in patients with disease limited to the liver and in whom the primary tumor was resected. Hepatic intra-arterial therapies are well tolerated in the majority of patients with NETs and liver metastases and associated with both clinical improvement and tumor stabilization for prolonged periods. These therapies should be always considered, irrespective of the presence of extrahepatic metastasis.

Mutation and reassortment of highly pathogenic avian influenza A(H5N1) viruses at the animal-human interface remain a major concern for emergence of viruses with pandemic potential. To understand the relationship of H5N1 viruses circulating in poultry and those isolated from humans, comprehensive phylogenetic and molecular analyses of viruses collected from both hosts in Vietnam between 2003 and 2010 were performed. We examined the temporal and spatial distribution of human cases relative to H5N1 poultry outbreaks and characterized the genetic lineages and amino acid substitutions in each gene segment identified in humans relative to closely related viruses from avian hosts. Six hemagglutinin clades and 8 genotypes were identified in humans, all of which were initially identified in poultry. Several amino acid mutations throughout the genomes of viruses isolated from humans were identified, indicating the potential for poultry viruses infecting humans to rapidly acquire molecular markers associated with mammalian adaptation and antiviral resistance.

To evaluate the impact of an institutional protocol on patterns of use and outcomes of inferior vena cava filters (IVCF). Following a multidisciplinary effort, an institutional protocol involving dedicated follow-up of patients receiving IVCF and a physician education program regarding IVCF utilization, was established. We prospectively collected data of patients who received IVCF during 2015–2016, following protocol implementation (POST group). For comparison, we reviewed records of patients who received IVCF during 2009–2014, before implementation of the institutional protocol (PRE group). In the PRE and POST groups, 76 and 38 IVCF per year were inserted respectively, with an overall decrease of 50%. IVCF were more likely to be placed for therapeutic rather than prophylactic indications in the POST compared to the PRE group (P = 0.003). Follow-up rates at our coagulation clinic were significantly higher in the POST than the PRE group (100 vs. 22.9%, P

BackgroundLiver metastases are relatively common in patients with metastatic medullary thyroid carcinoma (MTC), carrying a negative impact on disease prognosis. The options for selective therapy of liver metastases in MTC patients are limited to catheter-guided procedures such as trans-arterial chemoembolization (TACE). Data regarding the effectiveness and safety of this procedure in MTC are limited.AimTo explore the clinical outcome, survival and safety profile of TACE for liver metastases in a group of MTC patients.MethodsRetrospective case series of patients treated at a single tertiary University Medical Center from 2005 to 2015.ResultsSeven consecutive patients (mean age 64.5 ± 10.9 years, 5 females) with histologically confirmed MTC with liver metastases were included. Metastatic involvement of the liver was less than 50% of the liver volume in all patients. The median size of the largest liver lesion was 40 ± 6.9 mm. The patients underwent in total 20 sessions of TACE. Clinical improvement as well as tumor response (PR) were observed in all patients. The median time to tumor progression was 38 months (range 8–126). Three patients were still alive at the end of the follow-up period (a median overall survival rate of 57 ± 44 months).ConclusionTACE in MTC patients with hepatic metastases is usually well tolerated and induces both clinical improvement and tumor response for prolonged periods of time in the majority of patients. This therapeutic option should always be considered, irrespective of the presence of extrahepatic metastasis.

It was previously shown that hemagglutinin residues Thr155, Glu158, and Ser228 are crucial for the recognition of Neu5Gc. In this study, we demonstrated that the ability to bind the Neu5Gc-terminated receptor is related to the amino acid 145: viruses of years 1972-1999 with Lys145 bind to the receptor, whereas viruses with Asn145 do not. Sporadic appearance and disappearance of the ability to bind Neu5Gc oligosaccharides and the absence of Neu5Gc in the composition of human glycoconjugates indicate the non-adaptive nature of this ability. It was previously shown that unlike H1N1 viruses, H3N2 viruses of years 1968-1989 did not distinguish between Neu5Acα2-6Galβ1-4Glc (6'SL) and Neu5Acα2-6Galβ1-4GlcNAc (6'SLN). H3N2 viruses isolated after 1993 have acquired the ability to distinguish between 6'SL and 6'SLN, similarly to H1N1 viruses. We found that the affinity for 6'SLN has gradually increased from 1992 to 2003. After 2003, the viruses lost the ability to bind a number of sialosides, including 6'SL, that were good receptors for earlier H3N2 viruses, and retained high affinity for 6'SLN only, which correlated with the acquisition of new glycosylation sites at positions 122, 133, and 144, as well as Glu190Asp and Gly225Asp substitutions, in hemagglutinin. These substitutions are also responsible for the receptor-binding phenotype of human H1N1 viruses. We conclude that the convergent evolution of the receptor specificity of the H1N1 and H3N2 viruses indicates that 6'SLN is the optimal natural human receptor for influenza viruses.

Aim The utilization of inferior vena cava filter placement for pulmonary embolism prevention in elderly patients has not been well characterized. The present study aimed to review indications, complications and follow-up data of elderly patients undergoing inferior vena cava filter placement. Methods A retrospective review was carried out of consecutive admitted patients who underwent inferior vena cava filter insertion at a large university hospital with a level I trauma center. Results Overall, 455 retrievable filters were inserted between 2009 and 2014. A total of 133 patients (29.2%) were aged ≥70 years. Elderly patients were less likely to have their filter retrieved compared with non-elderly patients (5.3% vs 21.4%, P

The results of the vanadium reduction laboratory investigation are presented. Experiments were conducted with CaO-SiO2-Al2O3-V2O3slags in a wide range of compositions in an air atmosphere. A saturated iron- carbon melt was used as a reducing agent. The reduction kinetics was studied by sampling. V2O3reduction from slags having a viscosity of more than 0.5 Pa⋅s and containing less than 7.5–8.0% V2O3proceeds in a diffusion mode. The reaction is of the first order in vanadium. The process rate is inversely proportional to the square root of slag viscosity. A good agreement between the obtained data and the results of electrochemical studies on the cathodic reduction of vanadium was found. One made possible to deduce the rate equation of vanadium reduction by an iron-carbon melt depending on the volume concentration, temperature and slag viscosity. The calculated data for different slags acceptably check with those found by experiment.

Objectives: The objective of this study is to evaluate patterns of use and outcomes of retrievable inferior vena cava filters (rIVCF) in obstetric patients. Methods: A single center review of consecutive patients who underwent rIVCF placement during pregnancy/postpartum in 2005–2016. A pooled analysis of the relevant cases in the English literature was conducted. Results: The current cohort comprised 24 women, median age 27 [interquartile range 24–30] years. Among 10 filters placed during pregnancy, the most common indication (n = 4) was the need to withhold anticoagulation therapy before delivery, in the presence of acute thrombosis. In the postpartum period, most filters (64%, 9/14) were an adjunct to catheter-directed thrombolytic therapy. Inferior vena cava filters (IVCF)-related complications occurred in seven (29.2%). Retrieval was attempted in 21 patients (87.5%), and was technically successful in 19 (90.5%), for an overall removal rate of 79.1%. Pooled analysis of the literature (n = 98) showed comparable rates for filter removal and complications (81.6%, p = .78 and 24.2%, p = .60, respectively). Suprarenal placement (p = .12) and elective cesarean section (p = .19) did not reduce overall complication and retrieval rates. The estimated radiation dose among pregnant patients who underwent rIVCF placement without adjunct catheter directed thrombolysis (CDT) (mean 695 Gy cm2) was significantly lower than the radiation dose used in postpartum patients (1863 Gy cm2) or in pregnant patients in whom adjunct CDT was utilized (4059 Gy cm2) (p = .001 for both comparisons). Conclusions: Frequent rIVCF-related complications, radiation exposure, and removal failure call for their cautious utilization in obstetric patients. The role of suprarenal placement and elective cesarean section to improve outcomes has yet to be established.

GvHD results in death in the majority of steroid-resistant patients. This report assesses the safety and efficacy of two regional intra-arterial steroid (IAS) treatment protocols in the largest published cohort of patients with resistant/dependent hepatic and/or gastrointestinal GvHD, as well as identification of predictors of response to IAS and survival. One hundred and twenty patients with hepatic, gastrointestinal GvHD or both were given IAS. Gastrointestinal initial response (IR) and complete response (CR) were documented in 67.9% and 47.6%, respectively, whereas hepatic IR/CR in 54.9% and 33.3%, respectively. The predictors of gastrointestinal CR were lower peak GvHD and steroid-dependent (SD) GvHD. The predictors for hepatic CR were male patient, reduced intensity conditioning and SD GvHD. Twenty-six of the 120 patients (21.6%) are currently alive (median follow-up for the survivors 91.5 months). The 12 months' overall survival is 30% with no treatment-associated deaths. Predictors of 12 months' survival were as follows: first transplant, age

The noncovalent interactions that mediate trimerization of the influenza hemagglutinin (HA) are important determinants of its biological activities. Recent studies have demonstrated that mutations in the HA trimer interface affect the thermal and pH sensitivities of HA, suggesting a possible impact on vaccine stability (). We used size exclusion chromatography analysis of recombinant HA ectodomain to compare the differences among recombinant trimeric HA proteins from early 2009 pandemic H1N1 viruses, which dissociate to monomers, with those of more recent virus HAs that can be expressed as trimers. We analyzed differences among the HA sequences and identified intermolecular interactions mediated by the residue at position 374 (HA0 numbering) of the HA2 subdomain as critical for HA trimer stability. Crystallographic analyses of HA from the recent H1N1 virus A/Washington/5/2011 highlight the structural basis for this observed phenotype. It remains to be seen whether more recent viruses with this mutation will yield more stable vaccines in the future. IMPORTANCE Hemagglutinins from the early 2009 H1N1 pandemic viruses are unable to maintain a trimeric complex when expressed in a recombinant system. However, HAs from 2010 and 2011 strains are more stable, and our work highlights that the improvement in stability can be attributed to an E374K substitution in the HA2 subunit of the stalk that emerged naturally in the circulating viruses.

Development and improvement of quality control tests for live attenuated vaccines are a high priority because of safety concerns. Live attenuated influenza vaccine (LAIV) viruses are 6:2 reassortants containing the hemagglutinin (HA) and neuraminidase (NA) gene segments from circulating influenza viruses to induce protective immune responses, and the six internal gene segments from a cold-adapted Master Donor Virus (MDV). LAIV candidate viruses for the 2012–2013 seasons, A/Victoria/361/2011-CDC-LV1 (LV1) and B/Texas/06/2011-CDC-LV2B (LV2B), were created by classical reassortment of A/Victoria/361/2011 and MDV-A A/Leningrad/134/17/57 (H2N2) or B/Texas/06/2011 and MDV-B B/USSR/60/69. In an attempt to provide better identity and stability testing for quality control of LV1 and LV2B, sensitive real-time RT-PCR assays (rRT-PCR) were developed to detect the presence of undesired gene segments (HA and NA from MDV and the six internal genes from the seasonal influenza viruses). The sensitivity of rRT-PCR assays designed for each gene segment ranged from 0.08 to 0.8 EID50 (50% of Egg Infectious Dose) per reaction for the detection of undesired genes in LV1 and from 0.1 to 1 EID50 per reaction for the detection of undesired genes in LV2B. No undesired genes were detected either before or after five passages of LV1 or LV2B in eggs. The complete genome sequencing of LV1 and LV2B confirmed the results of rRT-PCR, demonstrating the utility of the new rRT-PCR assays to provide the evidence for the homogeneity of the prepared vaccine candidate.

Percutaneous endovascular revascularization is emerging as the first line treatment for peripheral artery disease for both intermittent claudication and chronic critical limb ischemia. Radiation doses for these interventions have not been well documented.A single center retrospective study of therapeutic endovascular lower extremity interventions performed between September 2006 and December 2011 was undertaken. Collected data included patient demographics, procedure indication, procedural access, anatomic location of occlusive disease (pelvis, thigh, below-knee, or multilevel), and radiation exposure parameters including dose area product (DAP) and fluoroscopy time.Data was available for 382 procedures performed in 313 patients. Eighteen procedures bilateral procedures were excluded. Access site and complete anatomic data were available for 346 procedures. DAP was significantly higher for procedures performed in the pelvis compared with thigh procedures (179.6 vs 63.2 Gy*cm(2); P .0001) and below-knee procedures (179.6 vs 28.9 Gy*cm(2); P .0001), despite shorter fluoroscopy times (11.8 vs 16.4 minutes; P .0001 and 11.1 vs 31.06 minutes; P .0001, respectively). Procedure access-site affected radiation dose as well; contralateral up-and-over access resulted in a higher DAP than antegrade access (112.2 vs 42.6 Gy*cm(2); P .0001). In a multivariable analysis, anatomic location of the procedure showed the strongest association with radiation dose (P .0001).Percutaneous endovascular revascularization for lower extremity peripheral artery disease involves a substantial radiation dose, comparable, on average, to a computed tomography scan of the abdomen and pelvis. Procedures performed in the pelvis for intermittent claudication involve more radiation than thigh or below-knee procedures for chronic critical limb ischemia. Radiation dose should be considered when planning these procedures.

We assessed drug susceptibilities of 125 avian influenza A(H5N1) viruses isolated from poultry in Vietnam during 2009–2011. Of 25 clade 1.1 viruses, all possessed a marker of resistance to M2 blockers amantadine and rimantadine; 24 were inhibited by neuraminidase inhibitors. One clade 1.1 virus contained the R430W neuraminidase gene and reduced inhibition by oseltamivir, zanamivir, and laninamivir 12-, 73-, and 29-fold, respectively. Three of 30 clade 2.3.4 viruses contained a I223T mutation and showed 7-fold reduced inhibition by oseltamivir. One of 70 clade 2.3.2.1 viruses had the H275Y marker of oseltamivir resistance and exhibited highly reduced inhibition by oseltamivir and peramivir; antiviral agents DAS181 and favipiravir inhibited H275Y mutant virus replication in MDCK-SIAT1 cells. Replicative fitness of the H275Y mutant virus was comparable to that of wildtype virus. These findings highlight the role of drug susceptibility monitoring of H5N1 subtype viruses circulating among birds to inform antiviral stockpiling decisions for pandemic preparedness.

In August 2011, one of the earliest cases of influenza A(H3N2) variant [A(H3N2)v] virus infection was hospitalized with severe illness. To investigate the potential for healthcare-associated transmission of influenza A(H3N2)v, we evaluated both healthcare providers and patient contacts of the case. We found that healthcare-associated transmission was unlikely.

We investigated unusual crow mortality in Bangladesh during January-February 2011 at two sites. Crows of two species, Corvus splendens and C. macrorhynchos, were found sick and dead during the outbreaks. In selected crow roosts, morbidity was ~1 % and mortality was ~4 % during the investigation. Highly pathogenic avian influenza virus H5N1 clade 2.3.2.1 was isolated from dead crows. All isolates were closely related to A/duck/India/02CA10/2011 (H5N1) with 99.8 % and A/crow/Bangladesh/11rs1984-15/2011 (H5N1) virus with 99 % nucleotide sequence identity in their HA genes. The phylogenetic cluster of Bangladesh viruses suggested a common ancestor with viruses found in poultry from India, Myanmar and Nepal. Histopathological changes and immunohistochemistry staining in brain, pancreas, liver, heart, kidney, bursa of Fabricius, rectum, and cloaca were consistent with influenza virus infection. Through our limited investigation in domesticated birds near the crow roosts, we did not identify any samples that tested positive for influenza virus A/H5N1. However, environmental samples collected from live-bird markets near an outbreak site during the month of the outbreaks tested very weakly positive for influenza virus A/H5N1 in clade 2.3.2.1-specific rRT-PCR. Continuation of surveillance in wild and domestic birds may identify evolution of new avian influenza virus and associated public-health risks.