The course of pathophysiological mechanisms involved in fragile X-associated tremor/ataxia syndrome (FXTAS) remains largely unknown. Previous proteomics and metabolomics studies conducted in blood ...samples collected from FMR1 premutation carriers with FXTAS reported abnormalities in energy metabolism, and precursors of gluconeogenesis showed significant changes in plasma expression levels in FMR1 premutation carriers who developed FXTAS. We conducted an analysis of postmortem human brain tissues from 44 donors, 25 brains with FXTAS, and 19 matched controls. We quantified the metabolite relative abundance in the inferior temporal gyrus and the cerebellum using untargeted mass spectrometry (MS)-based metabolomics. We investigated how the metabolite type and abundance relate to the number of cytosine-guanine-guanine (CGG) repeats, to markers of neurodegeneration, and to the symptoms of FXTAS. A metabolomic analysis identified 191 primary metabolites, the data were log-transformed and normalized prior to the analysis, and the relative abundance was compared between the groups. The changes in the relative abundance of a set of metabolites were region-specific with some overlapping results; 22 metabolites showed alterations in the inferior temporal gyrus, while 21 showed differences in the cerebellum. The relative abundance of cytidine was decreased in the inferior temporal gyrus, and a lower abundance was found in the cases with larger CGG expansions; oleamide was significantly decreased in the cerebellum. The abundance of 11 metabolites was influenced by changes in the CGG repeat number. A histological evaluation found an association between the presence of microhemorrhages in the inferior temporal gyrus and a lower abundance of 2,5-dihydroxypyrazine. Our study identified alterations in the metabolites involved in the oxidative-stress response and bioenergetics in the brains of individuals with FXTAS. Significant changes in the abundance of cytidine and oleamide suggest their potential as biomarkers and therapeutic targets for FXTAS.
ABSTRACT
We report the discovery of two hot Jupiters orbiting the stars K2-237 and K2-238. We used photometric data from Campaigns 11 and 12 of the Kepler K2 mission and radial velocity data obtained ...using the HARPS, FEROS, and CORALIE spectrographs. K2-237 b and K2-238 b have masses of $1.60^{+0.11}_{-0.11}$ and $0.86^{+0.13}_{-0.12}\,M_\mathrm{Jup}$, radii of $1.65^{+0.07}_{-0.08}$ and $1.30^{+0.15}_{-0.14}\,R_\mathrm{Jup}$, and are orbiting their host stars in 2.18- and 3.20-d orbits, respectively. The large radius of K2-237 b leads us to conclude that this candidate corresponds to a highly inflated hot Jupiter. K2-238 b has a radius consistent with theoretical models, considering the high incident flux falling on the planet. We consider K2-237 b to be an excellent system for follow-up studies, since not only is it very inflated, but it also orbits a relatively bright star (V = 11.6).
Most species of filamentous cyanobacteria are capable of gliding motility, likely via a conserved type IV pilus-like system that may also secrete a motility-associated polysaccharide. In a subset of ...these organisms, motility is achieved only after the transient differentiation of hormogonia, which are specialized filaments that enter a nongrowth state dedicated to motility. Despite the fundamental importance of hormogonia to the life cycles of many filamentous cyanobacteria, the molecular regulation of hormogonium development is largely undefined. To systematically identify genes essential for hormogonium development and motility in the model heterocyst-forming filamentous cyanobacterium
, a forward genetic screen was employed. The first gene identified using this screen, designated
, encodes a putative O-linked β-
-acetylglucosamine transferase (OGT). The deletion of
abolished motility, while ectopic expression of
induced hormogonium development even under hormogonium-repressing conditions. Transcription of
is rapidly upregulated (1 h) following hormogonium induction, and an OgtA-GFPuv fusion protein localized to the cytoplasm. In developing hormogonia, accumulation of PilA but not HmpD is dependent on
Reverse transcription-quantitative PCR (RT-qPCR) analysis indicated equivalent levels of
transcript in the wild-type and Δ
mutant strains, while a reporter construct consisting of the intergenic region in the 5' direction of
fused to
produced lower levels of fluorescence in the Δ
mutant strain than in the wild type. The production of hormogonium polysaccharide in the Δ
mutant strain is reduced compared to that in the wild type but comparable to that in a
deletion strain. Collectively, these results imply that
-GlcNAc protein modification regulates the accumulation of PilA via a posttranscriptional mechanism in developing hormogonia.
Filamentous cyanobacteria are among the most developmentally complex prokaryotes. Species such as
develop an array of cell types, including nitrogen-fixing heterocysts, spore-like akinetes, and motile hormogonia, that function in dispersal as well as the establishment of nitrogen-fixing symbioses with plants and fungi. These symbioses are major contributors to global nitrogen fixation. Despite the fundamental importance of hormogonia to the life cycle of filamentous cyanobacteria and the establishment of symbioses, the molecular regulation of hormogonium development is largely undefined. We employed a genetic screen to identify genes essential for hormogonium development and motility in
The first gene identified using this screen encodes a eukaryotic-like O-linked β-
-acetylglucosamine transferase that is required for accumulation of PilA in hormogonia.
The aim of this study was to evaluate the presence of filamentous fungi and yeasts on the external surface of ants at hospitals. From March 2007 to February 2008, 2,899 ants were evaluated in two ...public hospitals in the city of Fortaleza, Ceará, in northeastern Brazil. The ants were attracted by nontoxic baits, distributed within critical and semicritical hospital areas. The fungi were identified through macro-and micromorphological analysis, biochemical profile, and growth in chromogenic medium. From this study, 5 genera and 13 species of ants were identified, from critical (8% of the collected ants) and semicritical (92%) areas, during the daytime (48%) and nighttime (52%) periods. In the mycological analysis, 75% of the ants were fungi carriers, with the species Tapinoma melanocephalum and species from the genus Pheidole having the most potential as carriers of airborne fungi (75 and 18%, respectively) and yeasts (6 and 1%, respectively). In summary, ants act as carriers of airborne fungi and yeasts, including some pathogenic species.
Oogenesis in fish is a process that involves cell proliferation, growth and maturation. In rivers blocked by hydroelectric dams, these factors can be altered and affect the reproduction mechanism of ...the species. Regarding this scenario, the present study aimed to describe oogenesis in two cichlids native to the Amazon basin, Geophagus argyrostictus and G. altifrons, during pre- and post-dam periods of the Xingu River. Females of both Geophagus species were captured and biometric measurements were taken. Afterwards, the fish were euthanized, and the gonads were removed and subjected to histological processing for light microscopy, scanning electron microscopy and immunoperoxidase staining. Oocyte diameter and zona radiata thickness were also measured. The ovaries appeared in pairs, where according to their shape, size, vascularization and cell organization, five stages were described for both species. In the post-dam period, there was a reduction in the mean diameter of the oocytes, especially type IV, and a decrease in the thickness of the zona radiata, mainly, in G. argyrostictus. In both species, there was a greater presence of oocyte atresia in the post-dam period. PCNA immunoreactivity was more intense in type I and II oocytes, while vitellogenin immunoreactivity occurred in the cytoplasm and follicular cells of oocytes III and IV. These data suggest that because of changes in the level/flow of the river, the gonads of these two species adjust to the new environment, with a decrease in mean diameter and zona radiata thickness of the oocytes, which can interfere with the reproduction of the animals.
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•Fish oogenesis is a process that involves cell proliferation, growth and maturation.•Oogenesis has been described in two congeners pre- and pos- dam in the Xingu River.•Hydroeletric dams affect the diameter, zona radiata thickness, and oocyte homeostasis.
Angiotensin peptides and lung cancer Gallagher, Patricia E; Cook, Katherine; Soto-Pantoja, David ...
Current cancer drug targets,
05/2011, Letnik:
11, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Lung cancer is a leading cause of death in both men and women, with over 1,000,000 new cases diagnosed worldwide annually and a 5-year survival rate of only 14%, a figure that has improved little in ...the past thirty years. This poor prognosis suggests a need for novel approaches for the treatment and prevention of lung cancer. The renin-angiotensin system is an established, primary regulator of blood pressure, homeostasis, and natriuresis; however, compelling evidence indicates that the angiotensin peptides also play a role in cell proliferation and inflammation. Angiotensin II is a vasoconstrictor, a mitogen, and an angiogenic factor, while angiotensin-(1-7) has vasodilator, anti-proliferative, and anti-angiogenic properties. This review focuses on studies examining the renin-angiotensin system in pulmonary cancers and whether clinical intervention of this pathway may serve as an effective chemotherapeutic and/or chemopreventive modality for lung cancer.
Patients with acute coronavirus disease 2019 (COVID-19) respiratory infection are associated with concomitant thromboembolic complications and a hypercoagulable state. Although these mechanisms are ...not completely understood, unique alterations in the serum markers for hemostasis and thrombosis have been detected. A high index of suspicion is required by vascular surgeons for patients presenting with this novel virus. We present the case of a 51-year-old man with acute COVID-19 pneumonia who developed phlegmasia cerulea dolens despite chronic warfarin therapy and a supratherapeutic international normalized ratio.
Context.
The Scorpius-Centaurus (Sco-Cen) young and nearby massive star-forming region is particularly well suited for extrasolar planet searches with both direct imaging and radial velocity (RV) ...techniques. The RV search, however, is challenging, as the stars are faster rotators on average than their older stellar counterparts of similar spectral types. Moreover, the RV time series show strong signatures of stellar variability (spots and faculae) and/or stellar pulsations.
Aims.
Our aim is to search for giant planets (GPs) and brown dwarfs at short orbital distances around star members of the Sco-Cen association. We also aim at using these data together with others available on young stars to estimate the GP occurrence rate for young stars for periods of up to 1000 days.
Methods.
We used the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph on the 3.6 m telescope at the La Silla Observatory to monitor 88
A – F
Sco-Cen stars. To improve our statistics and analysis, we combined this survey with two previous surveys that focused on young nearby stars (YNS) to compute companion occurrence rates from a sample of 176 young
A – M
stars.
Results.
We report the discovery of a massive hot-Jupiter candidate around HD 145467, together with the discovery of one probable short-period (
P <
10 days) brown dwarf around HD 149790. In addition, we confirm the binary nature of eight single-line binaries: HD 108857, HD 108904, HD 111102, HD 114319, HD 121176, HD 126488, HD 126838, and HD 133574. From our sample, we obtain a GP (
m
c
∈ 1; 13
M
Jup
) occurrence rate of 0.7
−0.2
+1.6
% for periods between 1 and 1000 days and a brown dwarf (
m
c
∈ 13; 80
M
Jup
) occurrence rate of 0.6
−0.2
+1.4
%, in the same period range. In addition, we report a possible lack of close (
P
∈ 1; 1000 days) GPs around young F-K stars compared to their older counterparts, with a confidence level of 95%.
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