[Cross-reaction of seasonal influenza vaccine immune serum against Eurasian Avian-like H1N1 swine influenza virus].

Objective: To evaluate the cross-reaction of seasonal influenza vaccine immune serum against Eurasian avian-like H1N1 swine influenza virus. Methods: Nine human infected Eurasian avian-like H1N1 swine influenza virus strains were obtained from national influenza surveillance network laboratories in Jiangsu, Hebei, Shandong, Yunnan, Hunan, Fujian and Tianjin provinces, and their genetic characteristics of hemagglutinin were analyzed by deep sequencing. 30 volunteers were recruited respectively from children (2-5 years old), adults (24-57 years old) and elderly (60-84 years old) who received 2019-2020 seasonal influenza vaccine in Anning city, Yunnan Province in October 2019, and serum samples were collected before and 1 month after vaccination. The hemagglutination inhibition test was used to evaluate the cross-reaction of serum before and after immunization against 4 strains of human infection with Eurasian avian-like H1N1 swine influenza virus isolated since 2015. Results: The homology of hemagglutinin genes of 9 Eurasian avian-like H1N1 swine influenza viruses was similar, but the difference of hemagglutinin heavy chain and light chain amino acid genes with A (H1N1) pdm09 (vaccine strain) were 90-101 and 24-30 amino acids respectively. The antibody titer of vaccine strain antiserum to vaccine strain was 2 560; the antibody titers of the vaccine strain antiserum to Eurasian avian-like H1N1 swine influenza virus and the Eurasian avian-like H1N1 swine influenza virus antiserum to vaccine strain were same as 640. The proportion of children, adults and elderly vaccinated with seasonal influenza vaccine with antibody titer ≥40 against vaccine strain was 90.0%, 70.0% and 73.3%, respectively; while the proportion merely were 46.7%, 36.7% and 33.3%-43.3% to 4 strains of Eurasian avian-like H1N1 swine influenza virus, respectively. Conclusion: Seasonal influenza vaccination does not provide effective cross-protection against Eurasian avian-like H1N1 swine influenza virus.

Elevated lactoferrin is associated with moderate to severe Clostridium difficile disease, stool toxin, and 027 infection.

We evaluated blood and fecal biomarkers as indicators of severity in symptomatic patients with confirmed Clostridium difficile infection (CDI). Recruitment included patients with CDI based on clinical symptoms and supporting laboratory findings. Disease severity was defined by physician's assessment and blood and fecal biomarkers were measured. Toxigenic culture done using spore enrichment and toxin B detected by tissue culture were done as confirmatory tests. Polymerase chain reaction (PCR) ribotyping was performed on each isolate. There were 98 patients recruited, with 85 (87%) confirmed cases of toxigenic CDI (21 severe, 57 moderate, and seven mild), of which 68 (80%) were also stool toxin-positive. Elevated lactoferrin (p = 0.01), increased white blood cell (WBC) count (p = 0.08), and low serum albumin (p = 0.03) were all associated with the more severe cases of CDI. Ribotype 027 infection accounted for 71% of severe cases (p < 0.01) and patients with stool toxin had significantly higher lactoferrin levels and WBC counts (p < 0.05). Our findings show that elevated fecal lactoferrin, along with increased WBC count and low serum albumin, were associated with more severe CDI. In addition, patients infected with ribotype 027 and those with stool toxin had significantly higher fecal lactoferrin and WBC counts.

Transport properties of warm dense neon and krypton at high pressures.

The transport properties of warm dense neon (Ne) and krypton (Kr) are studied by combining self-consistent fluid variational theory (SFVT) with linear response theory (LRT). The components are determined using the SFVT, and the transport parameters, including the electrical conductivity, thermal conductivity, and thermopower, are calculated with the LRT. The relevant scattering mechanisms, including electron-ion, electron-electron, and electron-atom scatterings, are taken into account. An effective potential model in combination with the Muffin-tin model is introduced to further improve the description for electron-atom scattering, which not only includes static, exchange, and polarization interactions but also considers the plasma environmental effects. It is found that for electron-atom scattering, the influence of the plasma density is significant at lower scattering energies but the effects are different for electron-Ne and electron-Kr scattering. For electron-Kr scattering, a plasma density-dependent Ramsauer-Townsend minimum is observed. The obtained transport parameters are compared with the available experiments and other simulations. The plasma phase transition of warm dense Kr is revisited from multiple perspectives based on the numerical simulation results for the electrical conductivity and thermopower. These observations may help one to better understand the transport properties of warm dense noble gases and are an important guide for future experimental designs and theoretical developments.

Fatigue behavior in Co-Cr-Ni-Mo medical wires drawn with different drawing practices.

35%Co-20%Cr-35%Ni-10%Mo alloy (MP35N) with a low titanium (LT) content is commonly used as the material for the manufacture of leads in medical applications such as Cardiac Rhythmic Management (CRM), neurostimulation and Deep Brain Stimulation (DBS). The material is drawn to thin wires, and this involves subjecting the material to extensive plastic deformation to obtain the desired mechanical and fatigue properties. The critical part in the medical device design requires understanding the relationship between the processing method, microstructure and their impact on the cyclic performance. In this study, the influence of drawing practices namely Full Die Drawing (FDD) and Half Die Drawing (HDD) on the cyclic performance of MP35NLT wires have been investigated, by differing the amount of plastic strain applied on the material. The as-drawn wires were subjected to rotary beam fatigue tests (R = -1) with varying stress amplitudes, and the microstructural factors controlling the Low Cycle Fatigue (LCF) and High Cycle Fatigue (HCF) performance were determined through post fatigued TEM investigations. The results conclude that there is a significant impact on the drawing techniques on the fatigue performance of MP35NLT wires, with the FDD wires having a higher endurance limit than the HDD drawn wire until 75% CW, but there was a slight drop in the fatigue performance when the CW was increased to 95%. This was attributed to the difference in grain sizes, dislocation structures, twin density, twin spacing, and grain boundary orientations observed between the two wires which contributed to contrasting cyclic behavior. The drop-in fatigue performance of the FDD wire upon an increased strain to 95% has been attributed to the shear band formations in the material, which increased the stress localization in the material bestowing to drop-in fatigue performance.

In pregnant mice, the infection of Toxoplasma gondii causes the decrease of CD4+CD25+ -regulatory T cells.

Acute maternal infection with Toxoplasma gondii during pregnancy is associated with adverse pregnancy outcomes. Although previous reports have indicated that T. gondii may result in abortion without direct transmission of the parasite to the foetus, the molecular mechanism remains unclear. CD4+CD25+-regulatory T cells are known to be involved in maternal tolerance toward the foetus-bearing alloantigens. With a model of pregnant mice infected with T. gondii, we found that Foxp3 mRNA expression levels in both splenocytes and placenta were reduced markedly during the process of infection. Furthermore, the numbers of splenic CD4+CD25+-regulatory T cells and placental Foxp3+ cells decreased synchronously in the infected mice, and the reduction of splenic CD4+CD25+-regulatory T cells were associated with apoptosis induced by the infection. Additionally, injection of pregnant mice with excretory-secretory antigens (ESA) of T. gondii also resulted in foetal loss, which could be partly prevented by adoptive transfer of CD4+CD25+-regulatory T cells from normal pregnant mice. These data suggest that foetal loss caused by T. gondii can be independent of vertical infection and that the decrease of CD4+CD25+-regulatory T cells during infection may represent a previously unrecognized mechanism for the pathogenesis of abortion caused by this parasite.

Evaluation of lactate production and clearance kinetics by 1H NMR in a model of brief repetitive cerebral ischemia.

Pilots of high-performance aircraft are subject to repeated transient cerebral ischemia during high-gravitational stress maneuvers. Previously we have demonstrated that repeated episodes of transient cerebral ischemia and reflow are cumulative and lactate accumulations appear to be exponential. To evaluate the metabolic events determining the kinetics of lactate accumulation, and therefore the rates of substrate utilization, we have used in vivo 1H nuclear magnetic resonance with a 5-s time resolution to measure lactate production and clearance. The individual rates for each animal were then used to predict the accumulation of lactate in the same animal during 30 episodes of ischemia and reflow. Lactate accumulation was modeled as the balance between a zero-order production process during the ischemic period and a first-order clearance process. The predicted lactate accumulation showed excellent agreement with the observed time course, validating the predictive power of the simple model used. The highly reproducible nature of this model and its accuracy in predicting lactate accumulation should enable more accurate studies of the deleterious effects of lactate accumulation in cerebral ischemia by providing a highly reproducible means for generating a specific level of lactate accumulation.

Concomitant EEG, lactate, and phosphorus changes by 1H and 31P NMR spectroscopy during repeated brief cerebral ischemia.

Pilots of high-performance aircraft are subject to transient loss of consciousness due to cerebral ischemia resulting from sudden high gravitational stress. To assess the effects of gravitational stress-induced blackout on cerebral metabolism and electrical function, we developed an animal model in which global cerebral ischemia is produced repeatedly at short intervals. Rats were prepared by ligation of subclavian and external carotid arteries and the right carotid artery was cannulated bidirectionally to measure circle of Willis and systemic pressures. Ischemia was induced by inflation of an occluder about the left carotid artery. Interleaved 31P and 1H NMR spectra were acquired on a 4.7-T Biospec system simultaneously with EEG recordings. We report results from 20 experiments of 30-min duration in which rats were subject to 30 1-min ischemia:reflow cycles of 10I:50R, 20I:40R, 30I:30R, and 40I:20R [numbers are seconds of ischemia (I) and reflow (R) during each 1-min cycle]. During ischemia the graded delivery of the ischemic insult permitted direct correlations between 2- to 5- and 7- to 20-Hz EEG activity and progressive changes in pH, lactate, ATP, phosphocreatine (PCr) and Pi. The best correlations were found between EEG activity and pH and PCr; correlation coefficients ranged from 0.93 to 0.95. A loss of EEG activity was observed without significant sustained energy loss in all but the most severe cycle.

The radiologic manifestations of Legionnaire's disease. The Ohio Community-Based Pneumonia Incidence Study Group.

STUDY OBJECTIVES: To study the serial radiographic manifestations of Legionnaire's disease from the initial presentation on admission to recovery using strict criteria for the diagnosis of infection. MATERIALS AND METHODS: We prospectively studied the chest radiographs of patients hospitalized with a diagnosis of community-acquired pneumonia in Summit County, Ohio between November 1990 and November 1992. Forty-three patients fulfilled strict criteria for legionellosis. The diagnosis of infection was based on the criteria of "definite" diagnosis as defined by the Ohio Community-Based Pneumonia Incidence Study Group report. The criteria included the isolation of the microorganism, the presence of a significant antibody rise, or the presence of Legionella antigen in the urine. RESULTS: Forty of 43 patients had admission radiographs interpreted as compatible with pneumonia. In spite of appropriate antimicrobial therapy, worsening of the infiltrates was found in more than half of the patients within the first week. Twenty-seven patients were observed to have pleural effusion during the course of hospitalization: 10 effusions were found on admission, another 14 developed during the first week, and 3 new effusions were discovered after the first week. Cavitation was found in only one patient. None of the patients had apical involvement. CONCLUSION: This study confirms previous reports using less stringent etiologic diagnosis criteria that chest radiographic findings in Legionnaire's disease are not specific. Even with appropriate therapy, more than half of the patients will have worsening of the infiltrates during the first week. Pleural effusion is common among our patients, and it is frequently detected during the serial radiographic studies during the first week of hospitalization. Chest radiography in Legionnaire's disease is useful only for the monitoring of disease progression and not for diagnostic purposes. In addition, worsening of infiltrates and pleural effusion are seen in more than half of the patients in spite of appropriate therapy and clinical improvement.

Formation of glycidyl methacrylate-DNA adducts in vivo.

In in vivo test, rats were orally administrated with glycidyl methacrylate (GMA) at respective doses of 250 mg/kg, 125 mg/kg and 62.5 mg/kg, 31.25 mg/kg and solvent as control for 14 days. DNA adducts produced in the liver, kidney, blood and testis were analyzed by RP-HPLC and nuclease P1 mediated 32P-postlabelling method. Results showed that several potential GMA-DNA adducts were formed in various organs (4 adducts in blood, 3 adducts in liver and kidney, 1 adduct in testis). A linear dose-response relationship was observed within certain dose levels. The relative adduct labeling values failed to further increase any more when the concentration went up to 125 mg/kg. The order of adduct level with GMA was kidney, liver, blood and testis. The GMA adduct N3-methacrylate-2-hydroxypropyl-dCMP was found in kidney, liver and blood. These results indicated that GMA could react with negatively charged centers on DNA and form GMA-DNA adducts. If carcinogen induced DNA damage exceeds the ability of repair systems, gene mutation is induced. Therefore, study on molecular mechanism of gene mutation induced by DNA adducts is not only an important part of chemical-carcinogenesis, but also provides information on critical biomarkers for monitoring human exposure to genetic toxins.

In vitro metal ion release and biocompatibility of amorphous Mg67Zn28Ca5 alloy with/without gelatin coating.

Amorphous zinc-rich Mg-Zn-Ca alloys have exhibited good tissue compatibility and low hydrogen evolution in vivo. However, suboptimal cell-surface interaction on magnesium alloy surface observed in vitro could lead to reduced integration with host tissue for regenerative purpose. This study aims to improve cell-surface interaction of amorphous Mg67Zn28Ca5 alloy by coating a gelatin layer by electrospinning. Coated/uncoated alloys were immersed and extracted for 3 days under different CO2. The immersion results showed that pH and metal ion release in the alloy extracts were affected by gelatin coating and CO2, suggesting their roles in alloy biocorrosion and a mechanism has been proposed for the alloy-CO2 system with/without coating. Cytotoxicity results are evident that gelatin-coated alloy with 2-day crosslinking not only exhibited no indirect cytotoxicity, but also supported attachment of L929 and MG63 cell lines around/on the alloy with high viability. Therefore, amorphous Mg67Zn28Ca5 alloy coated with gelatin by electrospinning technique provides a useful method to improve alloy biocompatibility.

TAK1 regulates SCF expression to modulate PKBα activity that protects keratinocytes from ROS-induced apoptosis.

Dysregulated reactive oxygen species (ROS) generation contributes to many human pathologies, including cancer and diabetes. During normal wound repair, inflammation-induced ROS production must be tightly controlled, but the mechanisms reining their generation remain unclear. Herein, we show that transforming growth factor ß-activated kinase 1 (TAK1) directly regulates stem cell factor (SCF) expression, which activates the protein kinase B (PKB)α pro-survival pathway in a cell-autonomous manner to protect keratinocytes from ROS-mediated cell death. TAK1 is a pivotal inflammatory mediator whose expression was transiently elevated during wound healing, paralleling the ROS production profile. TAK1 deficiency in keratinocytes led to increased apoptosis in response to anoikis and TNF-α treatment and was associated with elevated ROS level as analyzed by FACS. Using organotypic skin co-culture and comparative growth factor array analysis, we revealed a cell-autonomous mechanism that involved the SCF/c-Kit/PKBα signaling cascade. Ectopic expression of TAK1 or treatment with exogenous recombinant SCF restored the increased ROS production and apoptotic cell death in TAK1-deficient keratinocytes. Conversely, normal keratinocytes treated with various inhibitors targeting the SCF/c-Kit/PKBα pathway exhibited increased ROS production and TNF-α- or anoikis-induced apoptosis. Our study reveals a novel anti-apoptotic role for SCF in keratinocytes and identifies TAK1 as a novel player uniting inflammation and ROS regulation in skin redox biology.

Improving head growth in very preterm infants--a randomised controlled trial I: neonatal outcomes.

BACKGROUND: Infants born very preterm are at an increased risk of poor growth in the post-natal period. Poor brain growth in this critical period may result from inadequate nutrition, and has long-term effects on neurodevelopmental outcome. AIMS: To examine the feasibility of providing macronutrients at amounts above current recommendations (hyperalimentation) to improve nutrition and head growth in preterm infants. METHODS: 142 infants <29 weeks' gestation were randomised to hyperalimented or standard parenteral and enteral nutrition. Growth was monitored from birth to 36 weeks' postmenstrual age (PMA). The primary outcome measure was occipitofrontal circumference (OFC) at 36 weeks' PMA. RESULTS: 55 infants in the intervention group and 59 infants in the control group survived to 36 weeks' PMA. 11 (16%) infants in the intervention group and 13 (18%) infants in the control group were small for gestational age (SGA). There was no statistically significant difference between the two groups in the primary outcome measure or other growth variables. Babies in the intervention group received significantly more energy and protein, but 80% were still in a cumulative protein/energy deficit at the end of 4 weeks. 20 (24%, p = 0.008) of those in deficit at 4 weeks had an OFC of more than 2 SD below the mean at 36 weeks' PMA, as opposed to none of those not in deficit. CONCLUSION: Cumulative energy/protein deficit is predictive of poor head growth, but the delivery of adequate intakes remains a challenge in the preterm.

Portfolio of health advice for young people with disabilities transferring to adult care.

BACKGROUND: The transition from paediatric to adult services for young people with complex disabilities is fraught with anxieties for families. To facilitate the transition process a portfolio comprising reports from parents, paediatrician and therapists was collected and given to the young person and family on leaving school. AIM: To evaluate the young people and their parents' views of the usefulness of portfolios in providing comprehensive picture of their health needs. METHODS: A prospective study was performed. Eight families were interviewed and semi-quantitative feedback obtained using standardized questionnaires. RESULTS: Seven out of eight young people and their families were satisfied with the portfolios they received. All of them found the portfolios worthwhile and useful. A quarter of the families would like to have been consulted more about the content of the individual reports. CONCLUSIONS: Portfolios of health reports facilitate transfer of information when young people with disabilities move from paediatric to adult services. Ideally portfolios should be interagency, and include reports from education and social services.

Focal neuropathy in children with critical illness.

Four children are described who developed focal lower limb nerve palsies following critical illness. Two had clinical and/or neurophysiological evidence of simultaneous generalised critical illness polyneuropathy. The diagnosis was delayed in three patients due to the presence of central motor abnormalities and slow motor recovery. Follow-up from seven months to three years showed minimal or no recovery. In three, a vasculitic skin infarct, compartment syndrome and focal myositis could have caused nerve compression. We suggest that in critical illness peripheral nerves have an increased susceptibility to damage by local pressure.

A novel process for the production of penitrem mycotoxins by submerged fermentation of Penicillium nigricans.

A strain of Penicillium nigricans, which produces both the antifungal antibiotic griseofulvin and tremorgenic penitrem mycotoxins concurrently in static liquid culture, also elaborated both metabolites in submerged culture when stimulated by calcium chloride to sporulate. Maximum yield of penitrems (60 mg l-1) occurred within 5 d in a 60 l stirred fermenter, thus constituting the first significant process for penitrem production in submerged culture.