Kirkmcgregor2691
The electron donor cytochrome b5 (CybE/Cyb5) fuels the activity of the ergosterol biosynthesis-related P450 enzymes/P450s by providing electrons to P450s to promote ergosterol biosynthesis. Previous studies reported that lack of Aspergillus fumigatus (A. fumigatus) CybE reduces the proportion of ergosterol in total sterols and induces severe growth defects. However, the molecular characteristics of CybE and the underlying mechanism for CybE maintaining A. read more fumigatus growth remain poorly understood. Here, we found that CybE locates at the endoplasmic reticulum by its C-terminus with two transmembrane regions. Therefore, lack of the C-terminus of CybE is able to phenocopy a cybE deletion. Notably, cybE deletion reduced the accumulation of the sterol-rich plasma membrane domains (SRDs, the assembly platform of polarity factors/cell end markers and growth machinery) in hyphal tips and decreased membrane fluidity, which correspond to tardiness of hyphal extension and hypersensitivity to low temperature in cybE dele fumigatus, however, the potential mechanism remains elusive. Herein, we characterized the molecular features of CybE and found the C-terminus with two transmembrane domains are required for its ER localization and functions. In addition, we demonstrated that CprA, an electron donor-heme-independent P450 reductase, provides a reciprocal function for the missing cytochrome b5 protein-CybE in A. fumigatus CybE maintains the normal growth probably via supporting two crucial physiological processes, the SRD accumulation in hyphal tips and membrane fluidity. Therefore, our finding reveals the mechanisms underlying the regulatory effect of CybE on A. fumigatus growth and indicates that inhibition of CybE might be an effective approach for alleviating A. fumigatus infection.Methanogenic archaea have long been implicated in microbially influenced corrosion (MIC) of oil and gas infrastructure, yet a first understanding of the underlying molecular mechanisms has only recently emerged. We surveyed pipeline-associated microbiomes from geographically distinct oil field facilities and found methanogens to account for 0.2 to 9.3% of the 16S rRNA gene sequencing reads. Neither the type nor the abundance of the detected methanogens was correlated with the perceived severity of MIC in these pipelines. Using fluids from one pipeline, MIC was reproduced in the laboratory, both under stagnant conditions and in customized corrosion reactors simulating pipeline flow. High corrosion rates (up to 2.43 mm Fe0 · yr-1) with macroscopic, localized corrosion features were attributed to lithotrophic, mesophilic microbial activity. Other laboratory tests with the same waters yielded negligible corrosion rates (0.15 mm Fe0 · yr-1) biofilms. The micH gene, on the other hand, was absent in noncorrosive bionding of methanogenic MIC derived from pure culture work allowed us to develop a qPCR assay that distinguishes technically problematic from benign methanogens in a West African oil field. Detection of the same gene in geographically diverse samples from North America hints at the widespread applicability of this assay. The research presented here offers a step toward a mechanistic understanding of biocorrosion in oil fields and introduces a binary marker for (methanogenic) MIC that can find application in corrosion management programs in industrial settings.
To evaluate the normative profiles for neuroretinal rim area (RA) in a multiethnic Asian population.
Subjects were recruited from the Singapore Epidemiology of Eye Diseases (2009-2015) study and underwent standardised examinations. RA measurements were performed using Cirrus high-definition optical coherence tomography (Carl Zeiss Meditec). Multivariable linear regression with generalised estimating equation model was used to evaluate the associations between demographic, systemic and ocular factors with RA.
A total of 9394 eyes from 5116 subjects (1724 Chinese, 1463 Malay, 1929 Indian) were included in the final analysis. The mean (±SD) of RA was 1.28 (±0.23) mm
for Chinese, 1.33 (±0.26) mm
for Malays, and 1.23 (±0.23) mm
for Indians. The 5th percentile value for RA was 0.94 mm
for Chinese, 0.96 mm
for Malay, and 0.89 mm
for Indian. In multivariable analysis, following adjustment for age, gender, body mass index, diabetes mellitus, hyperlipidaemia, history of cataract surgery, axial length, intraocular pressure (IOP) and disc area, Indian eyes have smaller RA when compared with Malays (β=-0.074; 95% CI -0.090 to -0.058; p<0.001) and Chinese (β=-0.035; 95% CI -0.051 to -0.019; p<0.001), respectively. Additionally, older age (per decade, β=-0.022), male gender (β=-0.031), longer axial length (per mm, β=-0.025), spherical equivalent (per negative dioptre, β=-0.005), higher IOP (per mm Hg, β=-0.009) were associated with smaller RA (all p≤0.004).
In this multiethnic population-based study, we observed significantly smaller RA in Indian eyes, compared with Chinese and Malays. This indicates the need of a more refined ethnic-specific RA normative databases among Asians.
In this multiethnic population-based study, we observed significantly smaller RA in Indian eyes, compared with Chinese and Malays. This indicates the need of a more refined ethnic-specific RA normative databases among Asians.
Miyazaki syndrome is overshunting-associated myelopathy, which is a rare complication of ventriculoperitoneal shunt. We present the first case of Miyazaki syndrome caused by cystoperitoneal (CP) shunt for an arachnoid cyst (AC) in this report.
We report a case of a 42-year-old man with 12-year progressive spastic paraplegia, who underwent CP shunt for an AC at the age of 15 years. Although few findings suggested overshunting on symptoms and head computed tomography, contrast-enhanced magnetic resonance imaging revealed the engorgement of the cervical spinal epidural venous plexus compressing the spinal cord. Shunt valve replacement with a pressure-adjustable valve was performed. Postoperatively, the cervical cord compression by the enlarged spinal epidural venous plexus was completely improved, but, possibly due to delayed diagnosis and treatment, the patient's symptoms only partially improved.
When patients with a history of any kind of shunt surgery develop myelopathy, Miyazaki syndrome should be suspected and, for early diagnosis, cervical and/or contrast-enhanced magnetic resonance imaging should be performed.