Influence of indoor microbial aerosol on the welfare of meat ducks.

The aim of the study was to evaluate the effects of microbial aerosols on ducks' welfare and provide information on which to establish microbial aerosol concentration standards for poultry. A total of 1800 1-d-old Cherry Valley ducks were randomly divided into 5 groups (A, B, C, D and E) with 360 ducks in each. To obtain objective data, each group had three replications. Different microbial aerosol concentrations in different groups were created by controlling ventilation and bedding cleaning frequency. Group A was the control group and hygienic conditions deteriorated progressively from group B to E. A 6-stage Andersen impactor was used to detect the aerosol concentration of aerobes, fungi, gram-negative bacteria and an AGI-30 microbial air sampler detected endotoxins. Physiological stress was evaluated in the ducks by adrenocorticotropic hormone (ACTH) values in serum. To assess the effects of bioaerosol factors, welfare indicators including fluctuating asymmetry (FA), appearance and gait as well as the Lactobacillus caecal concentration were evaluated. The data showed group D had already reached the highest limit of concentration of airborne aerobic bacteria, airborne fungi, airborne gram-negative bacteria and airborne endotoxin. The ducks in this group had significantly increased serum ACTH values and significantly decreased caecal lactobacilli concentration. Furthermore, appearance and gait scores, wing length and overall FA and caecal Lactobacillus concentration in this group were significantly increased at 6 and 8 weeks of age. In conclusion, high concentrations of microbial aerosol adversely affected the welfare of meat ducks. The microbial aerosol values in group D suggest a preliminary upper limit concentration of bioaerosols in ambient air for healthy meat ducks.

The influences of ambient temperature and crude protein levels on performance and serum biochemical parameters in broilers.

This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28-32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially.

Molecular cloning and immune responsive expression of LGP2 gene, a pivotal member of the RLR gene family from Muscovy duck Cairina moschata.

Laboratory of genetics and physiology 2 (LGP2) is an important intracellular receptor that recognizes viral RNAs in innate immunity. In this study, a novel LGP2 cDNA was identified from the spleen of a Muscovy duck (Cairina moschata). The deduced amino acid sequence of Muscovy duck LGP2 (MDLGP2) consisted of 675 amino acid residues. The peptide contained two main structure domains: six important motifs, including a DExD/H box for RNA helicase activity in the RNA helicase region located at the N-terminal region, and two Zn2+-binding regions with an RNA-binding loop in the C-terminus regulatory domain (CTD). The MdLGP2 mRNA was ubiquitously expressed in the tested tissues, with high expression levels in glandular stomach, colon, ileum, crop, and caecum tissues, and low expression levels in the brain, skin, and heart. The mRNA expression of MdLGP2 was significantly upregulated in the brain, spleen, and lungs of ducks in the early stages of postinfection with H5N1 highly pathogenic avian influenza virus (HPAIV). These results suggested that MdLGP2 was involved in the early stages of antiviral innate immune response in ducks after infection with H5N1 HPAIV. However, whether it plays a positive or negative regulatory role in the host antiviral response requires further investigation.

Corresponding states principle and van der Waals potentials of Zn2, Cd2, and Hg2.

Based on the assumptions that the corresponding states principle is valid for the group 12 dimers and that the interaction potentials of these dimers can be described by the Tang-Toennies potential model, a set of correlation relations between the spectroscopic constants of these dimers are derived. Some recently measured spectroscopic constants satisfy these relations quite well, but older experimental data do not. These recent spectroscopic constants and the newly available dispersion coefficients are used to construct the entire van der Waals potentials of Zn2, Cd2, and Hg2. There are indications that the ground state Hg2 potential predicted by the present study is possibly the most accurate to date. No unequivocal conclusion can be made for Zn2 and Cd2 potentials. Compared with the recent experiments, the present Zn2 bond length is eight percent too small, and the present Cd2 bond length is eight percent too large. However, both Zn2 and Cd2 bond lengths predicted by the present study are in good agreement with the quantum Monte Carlo results.

Identification and expression profiling analysis of goose melanoma differentiation associated gene 5 (MDA5) gene.

Melanoma differentiation associated gene 5 (MDA5) is an important cytoplasmic receptor that recognizes long molecules of viral double-stranded RNA and single-stranded RNA with 5' triphosphate and mediates type I interferon secretion. In this study, the full-length MDA5 gene in the goose was identified and characterized. The cDNA of goose MDA5 was 3,306 bp in length with an open reading frame of 3,018 bp, which encoded a polypeptide of 1,005 amino acids. The deduced amino acid sequence contained 6 main structure domains including 2 caspase activation and recruitment domains, one DExD/H-box helicase domain, one type III restriction enzyme domain, one helicase conserved C-terminal domain, and one RIG-I C-terminal domain. Quantitative real-time PCR analysis indicated that goose MDA5 mRNA was constitutively expressed in all sampled tissues. It was highly expressed in the jejunum, trachea, ileum, colon, and kidney, and lowly expressed in the muscular stomach, glandular stomach, and muscle. A significant increase in the transcription of MDA5 was detected in the brain, spleen, and lungs of geese after infection with H5N1 highly pathogenic avian influenza virus compared with uninfected tissues. These findings indicated that goose MDA5 was an important receptor, involved in the antiviral innate immune defense to H5N1 highly pathogenic avian influenza virus in geese.

Molecular cloning, characterization, and expression analysis of the Muscovy duck Toll-like receptor 3 (MdTLR3) gene.

Toll-like receptor 3 (TLR3) is an important membrane-bound receptor for recognizing double-stranded RNA in innate immunity. In this study, we described the cloning and characterization of the Muscovy duck TLR3 (MdTLR3) gene. The full-length MdTLR3 cDNA (2,836 bp) encoded a polypeptide of 895 amino acids. The deduced amino acid sequence contained 4 main structural domains: a signal peptide, an extracellular leucine rich repeats domain, a transmembrane domain, and a Toll/IL-1 receptor domain. Quantitative real-time PCR analysis indicated that MdTLR3 mRNA was constitutively expressed in all sampled tissues of uninfected Muscovy duck except muscle. Expression of MdTLR3 in brain was significantly upregulated at 24 h (1.94-fold, P < 0.05), reached a peak at 48 h (4.64-fold, P < 0.05), and recovered to normal levels at 72 h postinfection with the H5N1 highly pathogenic avian influenza virus. In contrast, MdTLR3 expression was downregulated during the test period in spleen and lung. These results implicated MdTLR3 was a novel member of the TLR family, which is involved in the early stage of antiviral innate immunity.

[Consistency of peripheral whole blood and venous serum procalcitonin in children: a multicenter parallel controlled study].

Objective: To explore the consistency of peripheral whole blood and venous serum procalcitonin (PCT) levels, and the value of peripheral whole blood PCT in evaluating pediatric bacterial infection. Methods: This multicenter cross-sectional parallel control study was conducted in 11 children's hospital. All the 1 898 patients older than 28 days admitted to these hospitals from March 2018 to February 2019 had their peripheral whole blood and venous serum PCT detected simultaneously with unified equipment, reagent and method. According to the venous serum PCT level, the patients were stratified to subgroups. Analysis of variance and chi-square test were used to compare the demographic characteristics among groups. And the correlation between the peripheral blood and venous serum PCT level was investigated by quantitative Pearson correlation analysis.The PCT resultes were also converted into ranked data to further test the consistency between the two sampling methods by Spearman's rank correlation test. Furthermore, the ranked data were converted into binary data to evaluate the consistency and investigate the best cut-off of peripheral blood PCT level in predicting bacterial infection. Results: A total of 1 898 valid samples were included (1 098 males, 800 females),age 27.4(12.2,56.7) months. There was a good correlation between PCT values of peripheral whole blood and venous serum (r=0.97, P<0.01). The linear regression equation was PCTvenous serum=0.135+0.929×PCTperipheral whole blood. However, when stratified to 5 levels, PCT results showed diverse and unsatisfied consistency between the two sampling methods (r=0.51-0.92, all P<0.01). But after PCT was converted to ordinal categorical variables, the stratified analysis showed that the coincidence rate of the measured values by the two sampling methods in each boundary area was 84.9%-97.1%. The dichotomous variables also showed a good consistency (coincidence rate 96.8%-99.3%, Youden index 0.82-0.89). According to the severity of disease, the serum PCT value was classified into 4 intervals（<0.5、0.5-<2.0、2.0-<10.0、≥10.0 µg/L）, and the peripheral blood PCT value also showed a good predictive value (AUC value was 0.991 2-0.997 9). The optimal cut points of peripheral whole blood PCT value 0.5、1.0、2.0、10.0 µg/L corresponding to venous serum PCT values were 0.395, 0.595, 1.175 and 3.545 µg/L, respectively. Conclusions: There is a good correlation between peripheral whole blood PCT value and the venous serum PCT value, which means that the peripheral whole blood PCT could facilitate the identification of infection and clinical severity. Besides, the sampling of peripheral whole blood is simple and easy to repeat.

Decreased chaperone activity of alpha-crystallins in naphthalene-induced cataract possibly results from C-terminal truncation.

Naphthalene-induced cataract has been extensively used to test potential anticataract drugs. Because the morphology as well as the toxic manifestations of naphthalene-induced cataract are reported to be similar to that of age-related cataract, naphthalene cataractogenesis in rats has been used as a valuable animal model to study the aetiology of age-related cataract in humans. This study aimed to determine whether the molecular chaperone activity of the alpha-crystallins was altered in naphthalene-induced cataract, and to clarify the possible mechanism for these changes. The data showed that the chaperone activity of the alpha-crystallins decreased in naphthalene-induced cataract. By mass spectrometry, C-terminal truncation of 16 amino acids and other post-translational modifications such as acetylation, phosphorylation, oxidation and carbamylation of the alpha-crystallins were detected. Furthermore, the results suggested that, at the proteomics level, naphthalene-induced cataract is a valuable animal model for the study of age-related cataract in humans.

Abciximab and excessive bleeding in patients undergoing emergency cardiac operations.

BACKGROUND: Abciximab (ReoPro; Eli Lilly and Co, Indianapolis, IN) is a monoclonal antibody that binds to the platelet glycoprotein IIb/IIIa receptor and produces powerful inhibition of platelet function. Clinical trials of abciximab in patients undergoing coronary angioplasty have demonstrated a reduction in thrombotic complications and have encouraged the widespread use of this agent. We have observed a substantial incidence of excessive bleeding among patients who receive abciximab and subsequently require emergency cardiac operations. METHODS: The records of 11 consecutive patients who required emergency cardiac operations after administration of abciximab and failed angioplasty or stent placement were reviewed. RESULTS: The interval from the cessation of abciximab administration to operation was critical in determining the degree of coagulopathy after cardiopulmonary bypass. The median values for postoperative chest drainage (1,300 versus 400 mL; p < 0.01), packed red blood cells transfused (6 versus 0 U; p = 0.02), platelets transfused (20 versus 0 packs; p = 0.02), and maximum activated clotting time (800 versus 528 seconds; p = 0.01) all were significantly greater in the early group (cardiac operation < 12 hours after abciximab administration; n = 6) compared with the late (cardiac operation >12 hours after abciximab administration; n = 5) group. CONCLUSIONS: This report suggests that the antiplatelet agent abciximab is associated with substantial bleeding when it is administered within 12 hours of operation.

Normothermic retrograde continuous cardioplegia for myocardial protection during cardiopulmonary bypass. A modified technique.

Normothermic retrograde continuous cardioplegia is a revolutionary development for myocardial preservation in cardiac surgery. Despite excellent reports regarding this technique, the surgical community has expressed concern over technical problems encountered. The method of normothermic retrograde continuous cardioplegia in current use requires both large total crystalloid volumes and large potassium loads to deliver adequate cardioplegia. We have developed a technique that eliminates these problems. The heart is stopped by an initial infusion of normothermic cardioplegic solution through a coronary sinus catheter. The infusate is then converted to normothermic pump blood. Small boluses of potassium chloride are added intermittently to maintain cardiac arrest. We applied this technique to 35 patients undergoing cardiac valve surgery. The average volume of crystalloid cardioplegia required was 125 mL (range, 40 to 155 mL), and the average total potassium load was 52 mEq (range, 2 to 100 mEq). Clinically significant sequelae were noted in 4 patients (11%), and 1 (3%) died of pneumonia on the 28th postoperative day. The method we describe is a safe and effective alternative to the current technique of normothermic retrograde continuous cardioplegia and offers both physiologic and technical advantages to patients undergoing cardiac valve procedures.

Synthesis of Tc-D,D-HMPAO and Tc-L,L-HMPAO and their comparison of chemical and biological properties.

Tc-D,D- and TC-L,L-HMPAO were synthesized. The stability of Tc-D,D- and TC-L,L-HMPAO in vitro is similar to that of d,l-isomers by the spectrophotometric and three strips methods. Cerebral uptake (%D in brain) for the L,L-isomer is higer than the D,D- and d,l-isomer in rats. Delayed studies shows that T-L,L-HMPAO reveals less washout and reflects a higher cerebral deposition properties than the D,D- and d,l-isomer.

Use of the total artificial heart as an interim device: initial experience in Pittsburgh with four patients.

The experimental use of the total artificial heart as an interim device before heart transplantation has demonstrated its potential usefulness. Once again there has been a reaffirmation of the basic principle in transplantation that careful selection of patients is a prerequisite for a high likelihood of success. Our experience suggests that advanced degrees of renal failure and liver dysfunction are not likely to be associated with a consistently useful interim support. Although our numbers of patients are quite small, we continue to be concerned by what appears to be the tendency for the development of severe thrombocytopenia not resulting from the use of heparin. Studies of platelet kinetics and deposition are planned for the future. Although no recipient has had direct evidence of thromboembolic events, systemic anticoagulation with heparin has been aggressively applied, and bleeding complications have been common. All Jarvik-7 hearts on which autopsies have been performed have demonstrated grossly evident platelet fibrin thrombi, especially around the inlet and outlet valve housings. It has not been our purpose to investigate the relative role for univentricular or biventricular assist. It is likely that a number of our patients might have benefited from left ventricular assistance alone. It would appear that additional patients are needed before strong conclusions can be formed regarding the potential benefits and risks of the current Jarvik-7 device or any total artificial heart as an interim method of support before heart transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)