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Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
The single intradermal comparative cervical tuberculin (SICCT) test and post-mortem examination are the main diagnostic tools for bovine tuberculosis (bTB) in cattle in the British Isles. Latent class modelling is often used to estimate the bTB test characteristics due to the absence of a gold standard. However, the reported sensitivity of especially the SICCT test has shown a lot of variation. We applied both the Hui–Walter latent class model under the Bayesian framework and the Bayesian model specified at the animal level, including various risk factors as predictors, to estimate the SICCT test and post-mortem test characteristics. Data were collected from all cattle slaughtered in abattoirs in Northern Ireland in 2015. Both models showed comparable posterior median estimation for the sensitivity of the SICCT test (88.61% and 90.56%, respectively) using standard interpretation and for post-mortem examination (53.65% and 53.79%, respectively). Both models showed almost identical posterior median estimates for the specificity (99.99% vs. 99.80% for SICCT test at standard interpretation and 99.66% vs. 99.86% for post-mortem examination). The animal-level model showed slightly narrower posterior 95% credible intervals. Notably, this study was carried out in slaughtered cattle which may not be representative for the general cattle population.
Frailty is associated with cognitive decline in older adults. However, the mechanisms explaining this relationship are poorly understood. We hypothesized that sleep quality may mediate the relationship between frailty and cognition.
154 participants aged between 50-90 years (mean = 69.1 years, SD = 9.2 years) from the McKnight Brain Registry were included.
Participants underwent a full neuropsychological evaluation, frailty and subjective sleep quality assessments. Direct relationships between frailty and cognitive function were assessed using linear regression models. Statistical mediation of these relationships by sleep quality was assessed using nonparametric bootstrapping procedures.
Frailty severity predicted weaker executive function (B = −2.77, β = −0.30, 95% CI = −4.05 – −1.29) and processing speed (B = −1.57, β = −0.17, 95% CI = −3.10 – −0.16). Poor sleep quality predicted poorer executive function (B = −0.47, β = −0.21, 95% CI = −0.79 – −0.08), processing speed (B = −0.64, β = −0.28, 95% CI = −0.98 – −0.31), learning (B = −0.42, β = −0.19, 95% CI = −0.76 – −0.05) and delayed recall (B = −0.41, β = −0.16, 95% CI = −0.80 – −0.31). Poor sleep quality mediated the relationships between frailty severity and executive function (B = −0.66, β = −0.07, 95% CI = −1.48 – −0.39), learning (B = −0.85, β = −0.07, 95% CI = −1.85 – −0.12), delayed recall (B = −0.47, β = −0.08, 95% CI = −2.12 – −0.39) and processing speed (B = −0.90, β = −0.09, 95% CI = −1.85 – −0.20).
Relationships between frailty severity and several cognitive outcomes were significantly mediated by poor sleep quality. Interventions to improve sleep quality may be promising avenues to prevent cognitive decline in frail older adults.
Social networks facilitate the transmission of hepatitis C virus (HCV) in people who inject drugs (PWID). The aim of this study was to assess how certain network structural characteristics are related to HCV infections in PWID and to determine the most susceptible individuals for HCV transmission in a network of PWID. PWID (N = 80) from central China were recruited from a previous follow-up case-control study. Demographic and behavioural information was obtained from a computerized database for each group. HCV RNA was extracted from blood specimens. Sequences were used to construct a phylogenetic tree and to determine genetic distances. Socio-metric social links were established between participants. Network measures were calculated using UCINET. Three HCV genotypes were identified, covering five subtypes. The density of the social networks for the whole sample (N = 80), case group (n = 31) and control group (n = 49) was 0.038, 0.054 and 0.008, respectively. PWID infected with HCV were in frequent contact with others within their group. There were four pairs of nodes with genotypic distances of 0.000 that were identified and clustered in subtypes 6a and 1b; each subject pair was linked and found in one clique. Three of the five most active nodes were infected with HCV. These three nodes served as a bridge, contributing to the connection of other nodes. These findings identify susceptible individuals for HCV transmission in PWID based on their frequent contact with others in the network. These results provide data that could be used for modelling HCV transmission patterns and in public health policies.
Background: 4H or POLR3-related leukodystrophy is an autosomal recessive disorder characterized by hypomyelination, hypodontia and hypogonadotropic hypogonadism caused by mutations in POLR3A, POLR3B and POLR1C. The endocrine abnormalities have never been systematically studied. Methods: A cross sectional international multicenter study was performed and the following variables were assessed: weight, height, head circumference, pubertal history, hormone levels and neurological and non-neurological features. Data was analyzed to determine whether there was a correlation between the presence of endocrine abnormalities and mutations in a specific gene and/or the presence of specific symptoms such as other non-neurological symptoms. Results: Data was collected on 156 patients. Endocrine data were available for 144 patients. The most common endocrine abnormalities seen in this cohort were short stature (54/90 patients (60%)) and delayed puberty (53/70 patients (76%)). 13 of the 58 patients tested (22%) had abnormal thyroid function. Patients with POLR3A mutations were more likely to have endocrine abnormalities. Conclusions: Our results confirm that the most common endocrine features in 4H leukodystrophy are short stature and pubertal abnormalities. However, the other potential endocrine abnormalities are typically under-investigated in this patient population. A prospective study is required to investigate the extent and severity of the endocrine abnormalities in 4H leukodystrophy.
This model, proposed by T. Nagylaki, describes the evolution of two alleles under the joint action of selection, migration, and partial panmixia – a non-local term, for the complete dominance case, where g(x) is assumed to change sign at least once to reflect the diversity of the environment. First, properties for general non-local problems are studied. Then, existence of non-trivial steady states, in terms of the diffusion coefficient d and the partial panmixia rate b, is obtained under different signs of the integral ∫Ωg(x)dx. Furthermore, stability and instability properties for non-trivial steady states, as well as the trivial steady states u ≡ 0 and u ≡ 1 are investigated. Our results illustrate how the non-local term – namely, the partial panmixia – helps the migration in this model.
Cholera is one of a number of infectious diseases that appears to be influenced by climate, geography and other natural environments. This study analysed the environmental factors of the spatial distribution of cholera in China. It shows that temperature, precipitation, elevation, and distance to the coastline have significant impact on the distribution of cholera. It also reveals the oceanic environmental factors associated with cholera in Zhejiang, which is a coastal province of China, using both remote sensing (RS) and geographical information systems (GIS). The analysis has validated the correlation between indirect satellite measurements of sea surface temperature (SST), sea surface height (SSH) and ocean chlorophyll concentration (OCC) and the local number of cholera cases based on 8-year monthly data from 2001 to 2008. The results show the number of cholera cases has been strongly affected by the variables of SST, SSH and OCC. Utilizing this information, a cholera prediction model has been established based on the oceanic and climatic environmental factors. The model indicates that RS and GIS have great potential for designing an early warning system for cholera.
Nursing homes (NHs) have been implicated as significant reservoirs of antibiotic-resistant organisms causing severe infectious disease. We investigated the prevalence and molecular epidemiology of, and risk factors for, faecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E). A multicentre cross-sectional study was conducted in seven NHs in Shanghai between March 2014 and May 2014. Antimicrobial susceptibility testing and polymerase chain reaction were used to detect genes coding for ESBLs and carbapenemases. NH records at individual-resident level and facility level were examined for potential risk factors. Four hundred and fifty-seven Enterobacteriaceae isolates were collected of which 183 (46·92%) were colonized by ESBL-E. CTX-M enzymes (198/200, 99%) predominated, with CTX-M-14 (84/200, 42%) the most common types. Two carbapenemase producers harboured blaKPC-2. Resistance rates to carbapenems, TZP, AK, FOS, CL and TGC were low. History of invasive procedures [odds ratio (OR) 2·384, 95% confidence interval (CI) 1·318–4·310, P = 0·004], narrow-spectrum cephalosporins (OR 1·635, 95% CI 1·045–2·558, P = 0·031) and broad-spectrum cephalosporins (OR 3·276, 95% CI 1·278–8·398, P = 0·014) were independently associated with ESBL-E carriage. In conclusion, NH residents have a very high prevalence of faecal carriage of ESBL-E. Continuous and active surveillance is important, as are prudent infection control measures and antibiotic use to prevent and control the spread of these antibiotic-resistant strains.
We describe two cases of infant botulism due to Clostridium butyricum producing botulinum type E neurotoxin (BoNT/E) and a previously unreported environmental source. The infants presented at age 11 days with poor feeding and lethargy, hypotonia, dilated pupils and absent reflexes. Faecal samples were positive for C. butyricum BoNT/E. The infants recovered after treatment including botulism immune globulin intravenous (BIG-IV). C. butyricum BoNT/E was isolated from water from tanks housing pet ‘yellow-bellied’ terrapins (Trachemys scripta scripta): in case A the terrapins were in the infant's home; in case B a relative fed the terrapin prior to holding and feeding the infant when both visited another relative. C. butyricum isolates from the infants and the respective terrapin tank waters were indistinguishable by molecular typing. Review of a case of C. butyricum BoNT/E botulism in the UK found that there was a pet terrapin where the infant was living. It is concluded that the C. butyricum-producing BoNT type E in these cases of infant botulism most likely originated from pet terrapins. These findings reinforce public health advice that reptiles, including terrapins, are not suitable pets for children aged <5 years, and highlight the importance of hand washing after handling these pets.
In Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?
Received parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.
Factor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.
Although the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.
We report the optical properties of C60 determined from the variable angle ellipsometry and near normal incidence reflection / transmission (R.T) experiments, and of M6C60 from the R, T experiments. The measurements were performed on thin films (d∼1000 Å) of C60 and M6C60 deposited on both Si(100) and suprasil substrates. The onset for strong absorption across the HOMO-LUMO gap in CgQ is measured to be -2.3 eV, slightly larger than the gap values obtained from the x-ray photoelectron spectroscopy (XPS) and electron-energy-loss spectroscopy (EELS) experiments. The observed peak positions in ε2(ω) for M6C60 and C60 compares well with the recent band structure calculations and suggests that the M6C60 compounds exhibit only a weak hybridization between the C60 and M states.
The Raman-active modes of solid films of MxC60 (x-0, 6; M=K, Rb, Cs) and K3C60 have been studied experimentally. The mode-activity is dominated by intraball interactions, and the effect of the M + ions on the C60 spectrum is observed to be almost insensitive to the radius or mass of the alkali metal. Tangential modes of solid C60 are observed to soften in M660 by -60 cm−1, which can be attributed to a charge-transfer-induced elongation of the intraball bond lengths, similar to that observed in graphite intercalation compounds. Conversely, the radial modes are found to upshift slightly, indicating that a competing mechanism counteracts the effect of the bond elongation. For K3C60, six Raman lines have been observed in which the lowest frequency mode exhibits a Breit-Wigner-Fano lineshape, indicating a coupling between the lowest frequency Hq-derived intramolecular modes of C60 and a broad Raman-active continuum with the same symmetry lying lower in frequency.
The premixability of reagents used in chemical vapor deposition reactors is important to insure that gas feed lines and nozzles do not become clogged with particulates during operation. Even if reactants are to be kept separate until introduced into a reaction chamber, it is desirable to limit the number of particles formed. A reactor which utilizes laser light scattering to monitor particulate formation when gaseous reagents are mixed is described. The reaction of tin (IV) chloride with water is commonly used to produce tin oxide films by chemical vapor deposition. It was found by the light scattering experiment that at temperatures above about 110°C the number of particulates formed is greatly reduced. Therefore, it would be most desirable that these reagents be mixed above this temperature when depositing tin oxide from this reaction. The reaction of titanium tetrachloride with various amine was also investigated by this method. This reaction has been demonstrated to produce titanium nitride above 450°C. For each case, it was observed that there was a temperature above which the number of particulates was significantly reduced. This temperature was always below the optimal temperature for producing titanium nitride films.
For the material (Pb0.95Sn0.05Te)1-x(PbS)x nanostructuring from nucleation and growth and spinodal decomposition were reported to enhance the thermoelectric figure of merit over bulk PbTe, producing ZT of 1.1 - 1.4 at 650 K for x = 0.08. Thermoelectric modules made from (Pb0.95Sn0.05Te)1-x(PbS)x materials with various hot-side metal electrodes were fabricated and tested. Short circuit current was measured on unicouples of Pb0.95Sn0.05Te – PbS 8% (n-type) legs and Ag0.9Pb9Sn9Sb0.6Te20 (p-type) legs over 10 (A) for a hot side temperature of 870K, and a cold side of 300K. Hot pressed (Pb0.95Sn0.05Te)1-x(PbS)x materials were also investigated for module fabrication. Investigations of the electrical properties of hot-pressed (Pb0.95Sn0.05Te)1-x(PbS)x materials are presented along with the latest advancements in the fabrication and characteristics of modules based on the processing of these materials.