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In addition to fulfilling many breeders' curiosity, equine embryonic sex determination can have a profound commercial impact. However, the application of currently described assays for equine embryonic sexing has rendered variable diagnosis and validation rates, with sensitivity being the main problem. In addition, while pregnancy results of in vivo-flushed equine embryos following a needle aspiration biopsy equal those of non-biopsied embryos, the effect on in vitro-produced embryos is unknown. Here, we aimed to develop a highly sensitive and specific assay for equine sex determination that can be directly performed on few embryonic cells, and to test the effect of a needle aspiration biopsy on the viability of the in vitro-produced embryo. To this end, a multiplex quantitative real-time PCR (qPCR) assay with dual-labelled probes was designed to allow the simultaneous generation of both male-specific and control fragments in a single closed-tube reaction, avoiding potential sample loss or contamination. To improve sensitivity, multicopy and polymeric genes were chosen to be specifically amplified, i.e., eight copies of Y-chromosomal ETSTY5 as male-specific and four autosomal UBC monomers as control fragment. Specificity was enhanced by the equine-specific character of ETSTY5 and by using dual-labelled probes. The assay was optimised with equine male and female genomic DNA and demonstrated a 100% accuracy and a >95% qPCR efficiency down to 10 pg of DNA. The assay was subsequently applied to determine the sex of 44 in vitro-produced embryos, collecting trophectoderm biopsies by means of a needle aspiration biopsy and herniating cells. Of all trophectoderm biopsies and herniating cell samples (n = 54), 87% could be diagnosed. Assay results were validated on a second sample obtained from the biopsied embryo (n = 18) or, by ultrasound-based sex determination of the foetus (n = 7) following the transfer of the biopsied embryo to a recipient mare, with about half of the embryos being fillies and colts. The needle aspiration biopsy procedure did not impair initial pregnancy rate or early pregnancy losses as compared to non-biopsied embryos. In conclusion, we report a safe, reliable, fast, and cost-effective assay for equine sex determination which was validated for the sex determination of in vitro-produced embryos based on few embryonic cells, and needle aspiration biopsy did not impair the embryo's viability. The assay and safe biopsy strategy hold potential for other applications.

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Low carbon fuel and waste management policies at the federal and state levels have catalyzed the construction of California's wet anaerobic digestion (AD) facilities. Wet ADs can digest food waste and dairy manure to produce compressed natural gas (CNG) for natural gas vehicles or electricity for electric vehicles (EVs). Carbon capture and sequestration (CCS) of CO2 generated from AD reduces the fuel carbon intensity by carbon removal in addition to avoided methane emissions. Using a combined lifecycle and techno-economic analysis, we determine the most cost-effective design under current and forthcoming federal and state low carbon fuel policies. Under many scenarios, designs that convert biogas to electricity for EVs (Biogas to EV) are favored; however, CCS is only cost-effective in these systems with policy incentives that exceed $200/tonne of CO2 captured. Adding CCS to CNG-producing systems (Biogas to CNG) only requires a single unit operation to prepare the CO2 for sequestration, with a sequestration cost of $34/tonne. When maximizing negative emissions is the goal, incentives are needed to either (1) fund CCS with Biogas to EV designs or (2) favor CNG over electricity production from wet AD facilities.

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Double-walled carbon nanotubes (DWCNTs) were synthesized and continuously collected using a water-assisted floating catalyst chemical vapor deposition (FCCVD) method. Differing from the conventional water-assisted synthesis in which water vapor is one part of the carrier gas mixture, we included de-ionized water in the catalyst system, which achieved a more uniform and controlled distribution for efficient DWCNT production. Using a water-assisted FCCVD process with optimized conditions, a transition from multi- to double-walled CNTs was observed with a decrease in diameters from 19-23 nm to 10-15 nm in tandem with an elevated Raman IG/ID ratio up to 10.23, and corroborated from the decomposition peak shifts in thermogravimetric data. To characterize the mechanical and electrical improvements, the FCCVD-CNT/bismaleimide (BMI) composites with different water concentrations were manufactured, revealing high electrical conductivity of 1720 S/cm along the bundle alignment (collection) direction, and the nano-indentation tests showed an axial reduced modulus at 65 GPa. A consistent value of the anisotropic ratio at ~3 was observed comparing the longitudinal and transverse properties. The continuous capability of the presented method while maintaining high quality is expected to result in an improved DWCNT mass production process and potentially enhance the structural and electrical applications of CNT nanocomposites.

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AIM: The study aim to examine whether management commitment and prioritization of safety at the hospital had any relationship with health care workers' safety behaviour under pressure to deliver health care. BACKGROUND: Sub-Saharan Africa faces a human resource crisis in the health sector, leading to a compromise of the safety practices of nurses and other care providers. Hence there is a need to probe the influence of pressure for health service delivery on safety behaviour. METHODS: The sample consisted of 295 respondents consisting of nurses, medical doctors and biological scientists from two teaching hospitals (Tamale Teaching Hospital and Komfu Anokye Teaching Hospital). A quantitative research design approach was used. Simple linear regression was carried out to test the hypotheses formulated. RESULTS: The results showed that pressure for health service delivery negatively affected health care workers' safety behaviour whereas management commitment to safety and priority of safety at the hospital were positively related to safety behaviour. CONCLUSION: Priority and the commitment of management to safety can influence the safety behaviour of nurses and other caregivers who are under pressure to deliver quality health care to the great number of patients. IMPLICATION FOR NURSING MANAGEMENT: Upholding high safety standards by management can create an enabling environment that would compel nurses and other caregivers to provide apt safety behaviours which in the long run can improve the quality of safety of nurses and other care providers.

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Large scale manufacturing of electrically conductive carbon nanotube (CNT) sheets with production capability, low cost, and long-term electrical performance stability is still a challenge. A new method to fabricate highly conductive continuous buckypaper (CBP) with roll-to-roll production capability and relatively low cost is reported. The electrical conductivity of CBP can be improved to 7.6 × 104 S m-1 by using an oxidant chemical (i.e. HNO3 and I2) doping method. To compensate for the conductivity degradation caused by the instability of the oxidant chemical doping, a polymer layer of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) was coated on the chemically doped CBP. The fabricated highly conductive CBP showed stable electrical performance in air for more than a month. This CBP material with high electrical conductivity, relatively low cost, and roll-to-roll manufacturing capability could enable a wide range of engineering applications including flexible conductors, electromagnetic interference (EMI) shielding materials, and electrodes in energy devices.

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BACKGROUND: Congenital and inherited myopathies in dogs are faithful models of human muscle diseases and are being recognized with increasing frequency. In fact, canine models of dystrophin deficient muscular dystrophy and X-linked myotubular myopathy are of tremendous value in the translation of new and promising therapies for the treatment of these diseases. We have recently identified a family of Australian Rottweilers in which male puppies were clinically affected with severe muscle weakness and atrophy that resulted in early euthanasia or death. X-linked myotubular myopathy was suspected based on the early and severe clinical presentation and histopathological changes within muscle biopsies. The aim of this study was to determine the genetic basis for myopathy in these dogs and compare and contrast the clinical presentation, histopathology, ultrastructure, and mutation in this family of Rottweiler dogs with the previously described myotubular myopathy in Labrador retrievers. RESULTS: Histopathology, histochemistry, and ultrastructural examination of muscle biopsies from affected Rottweiler puppies were consistent with an X-linked myotubular myopathy. An unusual finding that differed from the previously reported Labradors and similar human cases was the presence of excessive autophagy and prominent autophagic vacuoles. Molecular investigations confirmed a missense mutation in exon 11 of MTM1 that was predicted to result in a non-functional phosphatase activity. Although the clinical presentations and histopathology were similar, the MTM1 p.(Q384P) mutation is different from the p.(N155K) mutation in exon 7 affecting Labrador retrievers with X-linked myotubular myopathy. CONCLUSIONS: Here we describe a second pathogenic mutation in MTM1 causing X-linked myotubular myopathy in dogs. Our findings suggest a variety of MTM1 mutations in dogs as seen in human patients. The number of MTM1 mutations resulting in similar severe and progressive clinical myopathy and histopathological changes are likely to increase as canine myopathies are further characterized.

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Loss-of-function mutations in the myotubularin gene (MTM1) cause X-linked myotubular myopathy (XLMTM), a fatal, congenital pediatric disease that affects the entire skeletal musculature. Systemic administration of a single dose of a recombinant serotype 8 adeno-associated virus (AAV8) vector expressing murine myotubularin to Mtm1-deficient knockout mice at the onset or at late stages of the disease resulted in robust improvement in motor activity and contractile force, corrected muscle pathology, and prolonged survival throughout a 6-month study. Similarly, single-dose intravascular delivery of a canine AAV8-MTM1 vector in XLMTM dogs markedly improved severe muscle weakness and respiratory impairment, and prolonged life span to more than 1 year in the absence of toxicity or a humoral or cell-mediated immune response. These results demonstrate the therapeutic efficacy of AAV-mediated gene therapy for myotubular myopathy in small- and large-animal models, and provide proof of concept for future clinical trials in XLMTM patients.

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BACKGROUND: Neonates are at high risk for bleeding complications after cardiovascular surgery. Activation of intravascular fibrinolysis is one of the principal effects of cardiopulmonary bypass that causes poor postoperative hemostasis. Antifibrinolytic medications such as tranexamic acid are often used as prophylaxis against fibrinolysis, but concentration/effect data to guide dosing are sparse for adults and have not been published for neonates. Higher concentrations of tranexamic acid than those necessary for inhibition of fibrinolysis may have adverse effects. Therefore, we investigated the concentration of tranexamic acid necessary to inhibit activated fibrinolysis in neonatal plasma. METHODS: We conducted an in vitro study using neonatal plasma derived from the placenta/cord units from 20 term, elective cesarean deliveries. Graded concentrations of tranexamic acid were added to aliquots of the pooled plasma before maximally activating fibrinolysis with high-dose tissue-type plasminogen activator. Thromboelastography was then performed with the primary outcome variable being lysis at 30 minutes. These procedures were repeated on pooled adult normal plasma and dilutions of neonatal plasma. RESULTS: The minimum concentrations of tranexamic acid to completely prevent fibrinolysis were 6.54 µg/mL (95% confidence interval, 5.19-7.91) for neonatal plasma and 17.5 µg/mL (95% confidence interval, 14.59-20.41) for adult plasma. Neonatal plasma requires a significantly lower concentration than adult plasma (P < 0.0001, 2-sided Wald test). CONCLUSIONS: Our data establish the minimal effective concentration of tranexamic acid necessary to completely prevent fibrinolysis in neonatal plasma in vitro. These data may be useful in designing a dosing scheme for tranexamic acid appropriate for neonates.

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Mutations in the human SEPN1 gene, encoding selenoprotein N (SepN), cause SEPN1-related myopathy (SEPN1-RM) characterized by muscle weakness, spinal rigidity, and respiratory insufficiency. As with other members of the selenoprotein family, selenoprotein N incorporates selenium in the form of selenocysteine (Sec). Most selenoproteins that have been functionally characterized are involved in oxidation-reduction (redox) reactions, with the Sec residue located at their catalytic site. To model SEPN1-RM, we generated a Sepn1-knockout (Sepn1(-/-)) mouse line. Homozygous Sepn1(-/-) mice are fertile, and their weight and lifespan are comparable to wild-type (WT) animals. Under baseline conditions, the muscle histology of Sepn1(-/-) mice remains normal, but subtle core lesions could be detected in skeletal muscle after inducing oxidative stress. Ryanodine receptor (RyR) calcium release channels showed lower sensitivity to caffeine in SepN deficient myofibers, suggesting a possible role of SepN in RyR regulation. SepN deficiency also leads to abnormal lung development characterized by enlarged alveoli, which is associated with decreased tissue elastance and increased quasi-static compliance of Sepn1(-/-) lungs. This finding raises the possibility that the respiratory syndrome observed in patients with SEPN1 mutations may have a primary pulmonary component in addition to the weakness of respiratory muscles.

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AIM: To establish baseline noninvasive carboxyhemoglobin (COHb) levels in children and determine the influence of exposure to environmental sources of carbon monoxide (CO), especially environmental tobacco smoke, on such levels. BACKGROUND: Second-hand smoking may be a risk factor for adverse outcomes following anesthesia and surgery in children (1) and may potentially be preventable. PATIENTS AND METHODS: Parents and their children between the ages of 1-12 were enrolled on the day of elective surgery. The preoperative COHb levels of the children were assessed noninvasively using a CO-Oximeter (Radical-7 Rainbow SET Pulse CO-Oximeter; Masimo, Irvine, CA, USA). The parents were asked to complete an environmental air-quality questionnaire. The COHb levels were tabulated and correlated with responses to the survey in aggregate analysis. Statistical analyses were performed using the nonparametric Mann-Whitney and Kruskal-Wallis tests. P < 0.05 was statistically significant. RESULTS: Two hundred children with their parents were enrolled. Children exposed to parental smoking had higher COHb levels than the children of nonsmoking controls. Higher COHb values were seen in the youngest children, ages 1-2, exposed to parental cigarette smoke. However, these trends did not reach statistical significance, and confidence intervals were wide. CONCLUSIONS: This study revealed interesting trends of COHb levels in children presenting for anesthesia and surgery. However, the COHb levels measured in our patients were close to the error margin of the device used in our study. An expected improvement in measurement technology may allow screening children for potential pulmonary perioperative risk factors in the future.

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This study assesses a possible relationship between chronic Chlamydia pneumoniae (Cpn) infection and lung cancer (LC). A total of 210 consecutive patients (136 M, 74 F) were diagnosed with LC during a 2-year period. Blood was obtained from 128 M and 70 F patients for Cpn serology. Repeat blood specimens were taken after 3 months. Throat specimens for Cpn DNA analysis by PCR were taken from 110/136 M and 63/74 F Seventy-four cytobrush specimens were taken and also analyzed by polymerase chain reaction (PCR). Fifty (29 M, 21 F) bronchial biopsies and 8 (6 M, 2 F) tumors resected at surgery were analyzed for Cpn by immunohistochemistry (IHC). Males had significantly more often squamous-cell carcinoma (SCC) than females. Other types of LC were more equally distributed between males and females. The difference between males and females regarding smoking history was significant, and male LC patients had significantly higher levels of IgG and/or IgA antibodies than female LC patients. Male and female LC patients had significantly higher prevalences of high antibody titers than controls. A high prevalence of unusually high titers of specific Cpn antibodies was found in male LC patients. This could indicate that LC may be induced by chronic Cpn infection, since stable high titers of Cpn antibodies, especially IgA, are a hallmark of chronic infections.

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Malignant melanoma is increasing in incidence in most countries. Distant metastases are common but intratracheal metastasis is extremely rare. We report a 54-year-old man who presented with increasing dyspnoea. Symptomatic treatment for asthma had been of no effect. Bronchoscopy showed that trachea was nearly occluded by a tumoral mass, and biopsy proved this to be a metastasis of malignant melanoma. The man's breathing difficulties disappeared after local laser therapy, but 2 months later he presented with symptoms of multiple brain metastases.

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Material from 117 consecutive patients with lung cancer was investigated with respect to serological markers for chronic Chlamydia pneumoniae infection. Specific C. pneumoniae IgA antibodies were found significantly more often in patients with lung cancer than in control groups with coronary heart disease and in healthy controls, even after adjustment for smoking. The results suggest that chronic C. pneumoniae infection is common in patients with lung cancer.

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