The criterion value of fetal cerebral lateral ventricular atrium width for diagnosis of ventriculomegaly

Aim: To determine the distribution of cerebral lateral ventricular atrium width (LVAW) as established according to gestational weeks, and calculate the criterion value of LVAW that differentiates normal fetuses from abnormal fetuses. Materials and Methods: A total of 832 patients meeting the study's criteria were included in the control group. An additional 43 fetuses with LVAW > ten mm formed the case group. Results: The criterion value of LVAW was 9.7 mm. It did not change significantly throughout gestation. In the case group, 23 fetuses were terminated for fetal abnormalities, two fetuses died in utero, and 18 infants were born alive. Most of the abnormal development coincided with LVAW values greater than 12 mm. Conclusion: The authors suggest 9.7 mm as the criterion value, based on receiver operating characteristic (ROC) curve analysis. When the LVAW is between 9.8 and 12 mm without other fetal abnormalities, it may be regarded as a variation of the normal

A case of McCune-Albright syndrome associated with Gs alpha mutation in the bone tissue

The syndrome of McCune-Albright syndrome (MAS) is clasically defined as a triad presentation with the findings of polyostotic fibrous dysplasia, cafe-au-lait spots, and sexual precocity. However, not all patients present with complete symptoms. A 52-year-old mail was diagnosed as having a variant of McCune-Albright syndrome with the following findings: polyostotic Fibrous dysplasia, acromegaly due to pituitary tumor and subclinical hyperthyroidism due to toxic multinodular goiter. Sexual precocity and cafe-au-lait spots were not noted. Acromegaly was confirmed by laboratory examination (IGF-1, glucose Suppression test and TRH stimulation test). Long acting somatostatin analogue was used as treatment. Although the pituitary tumor Could not be removed due to technical problems, mass lesions on the cranium were removed subtotally. Histopathological evaluation demonstrated that the lesion complied with fibrous dysplasia. Genomic DNAs were isolated from the craniofacial bones and peripheral leucocytes of the patient. After amplifying the related regions, Gs alpha (Gs alpha) gene was analysed by automatic DNA sequence analysis. Ail activating mutation of the Gs alpha gene (Arg 201 Cys) was found in the genomic DNA isolated from the bone tissue of the patient, but not in the genomic DNA isolated from the blood. We described a case of MAS associated with Gs alpha mutation in the bone tissue, presenting with polyostotic fibrous dysplasia, subclinical hyperthyroidism and acromegaly

Catalytic Ring-Opening of Cyclic Alcohols Enabled by PCET Activation of Strong O–H Bonds

We report a new photocatalytic protocol for the redox-neutral isomerization of cyclic alcohols to linear ketones via C–C bond scission. Mechanistic studies demonstrate that key alkoxy radical intermediates in this reaction are generated via the direct homolytic activation of alcohol O–H bonds in an unusual intramolecular PCET process, wherein the electron travels to a proximal radical cation in concert with proton transfer to a weak Brønsted base. Effective bond strength considerations are shown to accurately forecast the feasibility of alkoxy radical generation with a given oxidant/base pair

Enantioselective Photoredox Catalysis Enabled by Proton-Coupled Electron Transfer: Development of an Asymmetric Aza-Pinacol Cyclization

The first highly enantioselective catalytic protocol for the reductive coupling of ketones and hydrazones is reported. These reactions proceed through neutral ketyl radical intermediates generated via a concerted proton-coupled electron transfer (PCET) event jointly mediated by a chiral phosphoric acid catalyst and the photoredox catalyst Ir­(ppy)₂(dtbpy)­PF₆. Remarkably, these neutral ketyl radicals appear to remain H-bonded to the chiral conjugate base of the Brønsted acid during the course of a subsequent C–C bond-forming step, furnishing <i>syn</i> 1,2-amino alcohol derivatives with excellent levels of diastereo- and enantioselectivity. This work provides the first demonstration of the feasibility and potential benefits of concerted PCET activation in asymmetric catalysis

Discovery and mechanistic study of a photocatalytic indoline dehydrogenation for the synthesis of elbasvir

Elbasvir is a potent NS5A antagonist for the treatment of chronic hepatitis C. A seemingly trivial indoline oxidation en route to the target compound was complicated by epimerization of a stereogenic hemiaminal center under most standard oxidation conditions. To address this issue, a novel visible light photoredox process for indoline oxidation was developed involving an iridium photosensitizer and environmentally-benign perester oxidant. The reaction was discovered through a high-throughput experimentation campaign and the optimized process was demonstrated on 100 g scale in flow to afford a key intermediate towards the target compound. A battery of kinetic, electrochemical, and spectroscopic studies of this process indicates a radical chain mechanism of dehydrogenation involving selective HAT from the substrate by an alkoxy radicals. Notably, isotope effects were used to validate the chain mechanism when quantum yield data proved ambiguous

Enantioselective Photoredox Catalysis Enabled by Proton-Coupled Electron Transfer: Development of an Asymmetric Aza-Pinacol Cyclization

The first highly enantioselective catalytic protocol for the reductive coupling of ketones and hydrazones is reported. These reactions proceed through neutral ketyl radical intermediates generated via a concerted proton-coupled electron transfer (PCET) event jointly mediated by a chiral phosphoric acid catalyst and the photoredox catalyst Ir­(ppy)₂(dtbpy)­PF₆. Remarkably, these neutral ketyl radicals appear to remain H-bonded to the chiral conjugate base of the Brønsted acid during the course of a subsequent C–C bond-forming step, furnishing <i>syn</i> 1,2-amino alcohol derivatives with excellent levels of diastereo- and enantioselectivity. This work provides the first demonstration of the feasibility and potential benefits of concerted PCET activation in asymmetric catalysis