122 research outputs found
Supernumerary chromosome 1 in interphase nuclei of atypical germ cells in paraffin-embedded human seminiferous tubules
2-(3-Cyanopropyldimethylsilyl)ethyl as a Polar Sulfur Protecting Group
Organosulfur compounds are ubiquitous in synthetic chemistry, biology and materials chemistry. The reactivity of free sulfhydryls requires their masking in many synthetic strategies. To facilitate the isolation of protected thiols by chromatography, we propose 2-(3-cyanopropyldimethylsilyl)ethyl as a polar protecting group analogue of 2-(trimethylsilyl)ethyl. The masked thiophenol is obtained in two synthetically complementing ways. Either an existing thiophenol is protected, or the protected thiol group is introduced by a cross-coupling reaction. In both cases the required reagents are readily available from inexpensive starting materials. Thiol protection and thiol introduction both tolerate a large variety of functional groups and substitution patterns, and the protected thiophenols are stable toward a broad range of reaction conditions. The stability of the protected derivatives in cross-coupling reactions and the mild reaction conditions for the release of the protecting group further emphasizes the potential of the methodology
Zystische Adventitiadegeneration (CAD) als Ursache einer invalidisierenden Claudicatio intermittens
Zusammenfassung: Bei einem 45-jĂ€hrigen Patienten mit wechselhaften IschĂ€miebeschwerden und initial limitierter Gehstrecke rechts von höchstens 50m fĂŒhrten die duplexsonographischen und angiographischen AbklĂ€rungen zur Verdachtsdiagnose einer zystischen Adventitiadegeneration. Intraoperativ zeigte sich ein zystisch aufgetriebenes Poplitealsegment mit Entleerung von gallertiger FlĂŒssigkeit. Aufgrund der langstreckigen VerĂ€nderung erfolgte die Segmentresektion der A.poplitea und Rekonstruktion mittels eines autologen Veneninterponats. Die CAD ist ein seltenes Krankheitsbild, an das gerade bei jungen Patienten ohne systemische Arteriosklerose gedacht werden sollte. Die Therapie ist je nach Fall chirurgisch erhaltend durch Zystenresektion mittels "Exarterektomie" oder gefĂ€Ăresezierend, insbesondere bei langstreckigen VerĂ€nderungen bzw. vollstĂ€ndiger Okklusion mittels Ersatz durch ein Veneninterpona
Mediolateral Damping of an Overhead Body Weight Support System Assists Stability During Treadmill Walking
Background
Body weight support systems with three or more degrees of freedom (3-DoF) are permissive and safe environments that provide unloading and allow unrestricted movement in any direction. This enables training of walking and balance control at an early stage in rehabilitation. Transparent systems generate a support force vector that is near vertical at all positions in the workspace to only minimally interfere with natural movement patterns. Patients with impaired balance, however, may benefit from additional mediolateral support that can be adjusted according to their capacity. An elegant solution for providing balance support might be by rendering viscous damping along the mediolateral axis via the software controller. Before use with patients, we evaluated if control-rendered mediolateral damping evokes the desired stability enhancement in able-bodied individuals. Methods
A transparent, cable-driven robotic body weight support system (FLOAT) was used to provide transparent body weight support with and without mediolateral damping to 21 able-bodied volunteers while walking at preferred gait velocity on a treadmill. Stability metrics reflecting resistance to small and large perturbations were derived from walking kinematics and compared between conditions and to free walking. Results
Compared to free walking, the application of body weight support per-se resulted in gait alterations typically associated with body weight support, namely increased step length and swing phase. Frontal plane dynamic stability, measured by kinematic variability and nonlinear dynamics of the center of mass, was increased under body weight support, indicating reduced balance requirements in both damped and undamped support conditions. Adding damping to the body weight support resulted in a greater increase of frontal plane stability. Conclusion
Adding mediolateral damping to 3-DoF body weight support systems is an effective method of increasing frontal plane stability during walking in able-bodied participants. Building on these results, adjustable mediolateral damping could enable therapists to select combinations of unloading and stability specifically for each patient and to adapt this in a task specific manner. This could extend the impact of transparent 3-DoF body weight support systems, enabling training of gait and active balance from an early time point onwards in the rehabilitation process for a wide range of mobility activities of daily life
Bicyclic PhenylâEthynyl Architectures: Synthesis of a 1,4-Bis(phenylbuta-1,3-diyn-1-yl) Benzene Banister
The novel diacetylene bridged terphenylic macrocycle 1 is presented and discussed in the context of rotationally restricted âGelĂ€nderâ oligomers. The 1,4âbis(phenylbutaâ1,3âdiynâ1âyl) benzene bridge of diacetylene 1 is significantly longer than its terphenyl backbone, forcing the bridge to bend around the central pylon. The synthesis of molecule 1 is based to a large extent on acetylene scaffolding strategies, profiting from orthogonal alkyne protection groups to close both macrocyclic subunits by oxidative acetylene coupling sequentially. The spatial arrangement and the dynamic enantiomerization process of the bicyclic target structure 1 are analyzed. Inâdepth NMR investigations not only reveal an unexpected spatial arrangement with both oligomer strands bent alongside the backbone, but also display the limited stability of the model compound in the presence of molecular oxygen
Asymptomatic HIV-people present different profile of sCD14, sRAGE, DNA damage and vitamins, according to the use of cART and CD4+ T cells restoration.
We aimed to analyze markers of immune activation, inflammation, and oxidative stress in 92 asymptomatic HIV-infected patients according to the adequate (AR, >500 cells/mm(3)) or inadequate (IR, nAR > LTNP > tAR > tIR. Higher levels of 8-isoprostane were observed in nIR. LTNP presented a higher retinol dosage than tAR and less genotoxic damage induced by oxidative stress than the other groups. We suggest that the therapy, despite being related to lesser immune activation and inflammation, alters the vitamin profile and consequently increases the oxidative stress of patients. In addition, the lowest genotoxic index for LTNP indicates that both VL and cART could be responsible for the increased DNA damage. More studies are needed to understand the influence of cART on persistent immune activation and inflammation
Author Correction: Whole-genome sequencing of 1,171 elderly admixed individuals from Brazil (vol 13, 1004, 2022)
Whole-genome sequencing of 1,171 elderly admixed individuals from Brazil
As whole-genome sequencing (WGS) becomes the gold standard tool for studying population genomics and medical applications, data on diverse non-European and admixed individuals are still scarce. Here, we present a high-coverage WGS dataset of 1,171 highly admixed elderly Brazilians from a census-based cohort, providing over 76 million variants, of which ~2 million are absent from large public databases. WGS enables identification of ~2,000 previously undescribed mobile element insertions without previous description, nearly 5âMb of genomic segments absent from the human genome reference, and over 140 alleles from HLA genes absent from public resources. We reclassify and curate pathogenicity assertions for nearly four hundred variants in genes associated with dominantly-inherited Mendelian disorders and calculate the incidence for selected recessive disorders, demonstrating the clinical usefulness of the present study. Finally, we observe that whole-genome and HLA imputation could be significantly improved compared to available datasets since rare variation represents the largest proportion of input from WGS. These results demonstrate that even smaller sample sizes of underrepresented populations bring relevant data for genomic studies, especially when exploring analyses allowed only by WGS
Interleukin-15 augments oxidative metabolism and fungicidal activity of human monocytes against Paracoccidioides brasiliensis
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