Rh(II)/Ag(I)-Cocatalyzed Three-Component Reaction via SN1/SN1'-Type Trapping of Oxonium Ylide with the Nicholas Intermediate

A Rh(II)/Ag(I)-cocatalyzed three-component reaction of propargylic alcohol-Co₂(CO)₆ complexes with diazo compounds and benzyl alcohols is described, which represents the first trapping process of oxonium ylides with carbocations via the S_N1/S_N1'-type pathway. This transformation provides an efficient approach for construction of dicobalt hexacarbonyl-complexed 3,3-disubstituted oxindoles. Further derivatization of the product, initiated by the deprivation of the dicobalt species, gives the 3,3-disubstituted oxindoles with the ene alkynyl group and the privileged spirooxindole-vinyldihydropyran structure.

A modified negative pressure wound therapy for the treatment of refractory wounds: A preliminary study

Negative pressure wound therapy (NPWT) is an important therapy for the management of refractory wounds. The aim of this retrospective preliminary study was to introduce a modified NPWT (m-NPWT) and compared the efficacy of it with conventional NPWT (c-NPWT) in the management of refractory wounds.A total of 127 patients with refractory wounds receiving the NPWT from January 2010 to October 2017 in our hospital were retrospectively reviewed. The demographics and clinical data were collected from medical records and compared between m-NPWT group and c-NPWT group.There were 65 patients in c-NPWT group and 62 patients in m-NPWT group. No significant difference was observed between 2 groups in antimicrobial use (P = .51), hospitalization time (P = .24), wound-healing rate (P = .44) or complication rate (P = .59). However, patients in m-NPWT group had shorter wound-healing time (24.82 vs 27.66 days, P < .01), less debridement times (1.23 vs 2.08, P < .01), less total cost (3743.93 vs 6344.33 yuan, P < .01) and higher satisfaction rate (56/62 vs 44/65, P = .02) compared to those in c-NPWT group.The m-NPWT technique was an efficient and safe alternative therapy for refractory wounds.

Opposing biological functions of the cytoplasm and nucleus DAXX modified by SUMO-2/3 in gastric cancer

Death domain-associated protein (DAXX) is a complex biological multifunctional protein and is involved in the tumorigenesis and progression of multiple cancers. The accumulation of DAXX in the nucleus is a common phenomenon in tumor cells. However, altering the subcellular localizations of DAXX results in different biological functions, and we also found that its nuclear/cytoplasmic ratio (NCR) was associated with poor prognosis in gastric cancer (GC). In this study, we investigated the effect of cytoplasmic and nuclear DAXX (cDAXX and nDAXX) in GC and the underlying mechanisms. Immunohistochemical detection performed in 323 GC tissues reveled that cDAXX was associated with a better survival, while high nDAXX expression suggested a poorer prognosis outcome. Upregulation of DAXX in the cytoplasm inhibited cell proliferation and promoted apoptosis, whereas downregulation of DAXX in the nucleus displayed opposite effects. Moreover, Transwell assays revealed that DAXX enhanced GC cell migration and invasion. Analysis from the Gene Expression Profile Interactive Analysis (GEPIA) database showed that the expression of DAXX was significantly associated with SUMO-2/3 in GC tissues. Co-immunoprecipitation combined with immunofluorescence analysis indicated that DAXX interacted directly with SUMO-2/3. Subsequently, down-regulating the expression of SUMO-2/3 resulted in altered subcellular localization of DAXX. Bioinformatics analysis showed that RanBP2 may act as SUMO E3 ligase to promote nuclear-plasma transport via combining with RanGAP1. Taken together, our results indicated that DAXX plays opposing roles in GC and suggest a new model whereby cDAXX, nDAXX, and SUMO-2/3 form a molecular network that regulates the subcellular localization of DAXX and thereby modulates its opposing biological effects. Thus, our findings provide a foundation for future studies of DAXX as a novel therapeutic target for patients with GC.

New Insights of Emerging SARS-CoV-2: Epidemiology, Etiology, Clinical Features, Clinical Treatment, and Prevention

Since the first reports that the novel coronavirus was showing human-to-human transmission characteristics and asymptomatic cases, the number of patients with associated pneumonia has continued to rise and the epidemic has grown. It now threatens the health and lives of people across the world. The governments of many countries have attached great importance to the prevention of SARS-CoV-2, via research into the etiology and epidemiology of this newly emerged disease. Clinical signs, treatment, and prevention characteristics of the novel coronavirus pneumonia have been receiving attention worldwide, especially from medical personnel. However, owing to the different experimental methods, sample sizes, sample sources, and research perspectives of various studies, results have been inconsistent, or relate to an isolated aspect of the virus or the disease it causes. Currently, systematic summary data on the novel coronavirus are limited. This review combines experimental and clinical evidence into a systematic analysis and summary of the current progress of research into SARS-CoV-2, from multiple perspectives, with the aim of gaining a better overall understanding of the disease. Our report provides important information for current clinicians, for the prevention and treatment of COVID-19 pneumonia.

Dysbiosis in Peripheral Blood Mononuclear Cell Virome Associated With Systemic Lupus Erythematosus

Objective: Pathogen infection plays a role in the development and progression of systemic lupus erythematosus (SLE). Previous studies showed that peripheral blood mononuclear cells (PBMCs) harbor many viral communities. However, little is known about the viral components and the expression profiles of SLE-associated virome. We aimed to identify viral taxonomic markers of SLE that might be used in the detection of disease or in predicting its outcome.

Methods: Non-human sequence data from high-throughput transcriptome sequencing of PBMC samples from 10 SLE patients and 10 healthy individuals were used for taxonomic alignment against an integrated virome reference genome database. Based on abundance profiles of SLE-associated virome species, genera, or host, Random Forests model was used to identify the viruses associated with SLE diagnostic markers. Spearman's correlation and functional clustering was used to analyze the interaction of candidate virome dysbiosis and SLE-associated differentially expressed genes.

Results: A total of 419 viruses (38 human associated viruses, 350 phage, and 31 other viruses) was detected and the diversity of the PBMC virome was significantly increased in patients with SLE compared to the healthy controls (HCs). Viral taxa discriminated the cases from the controls, with an area under the receiver operating characteristic curve of 0.883, 0.695, and 0.540 for species, genus, and host, respectively. Clinical subgroup analysis showed that candidate PBMC viral markers were associated with stable- and active-stage SLE. Functional analyses showed that virome dysbiosis was mainly relevant to cellular and metabolic processes.

Conclusion: We identified virome signatures associated with SLE, which might help develop tools to identify SLE patients or predict the disease stage.

Enantioselective three-component aminomethylation of α-diazo ketones with alcohols and 1,3,5-triazines

Enantioselective α-aminomethylation of carbonyl compounds constitutes a powerful protocol for introducing aminomethyl groups to simple organic molecules. However, current strategies rely on nucleophile-based enantioselective activation with inherently activated substrates only, and enantioselective protocol based on the activation of in situ-generated unstable formaldimines remains elusive, probably owing to their unstable nature and the lack of steric environment for efficient stereocontrols. Here, based on a rhodium/chiral phosphoric acid cooperative catalysis, we achieved an enantioselective three-component reaction of α-diazo ketones with alcohols and 1,3,5-triazines. A dual hydrogen bonding between the chiral phosphoric acid catalyst and two distinct active intermediates was proposed to be crucial for the efficient electrophile-based enantiocontrol. A series of chiral β-amino-α-hydroxy ketones including those derived from simple aliphatic alcohols, allylic alcohol, propargyl alcohol, complicated natural alcohols and water could all be prepared in high efficiency and enantioselectivity.

Strategies for enantioselective α-aminomethylation of carbonyl compounds rely on the chiral activation of stable ketones substrate. Here, the authors report a rhodium/chiral phosphoric acid cooperative catalysis for the three-component reaction of α-diazo ketones with alcohols and 1,3,5-triazines via imine chiral activation.

[Experimental study on the effect of olfactory training on olfactory function in mice with olfactory dysfunction]

Objective: To observe the effect of olfactory training on mice with olfactory dysfunction induced by 3-methylindole (3-MI). Methods: Thirty-one male BALB/c mice were randomly divided into 3 groups by random digits table: control group (group A, n=10), olfactory dysfunction group (group B, n=10) and olfactory dysfunction+olfactory training group (group C, n=11). Mice in group B and group C were intraperitoneally injected with 150 mg/kg 3-MI to induce olfactory dysfunction model, while mice in group A were intraperitoneally injected with corn oil of the same volume. From the first day after injection, mice in group C were treated with 4 kinds of odors by inhalation, while mice in group B were treated with distilled water by inhalation, with 2 times/d, 30 min/time/kind of odor, and continuous training for 28 d. Group A was not treated. Buried food pellet tests were conducted before injection and at 7, 14, 21 and 28 days after injection, respectively. The olfactory epithelium was harvested for observation of the number of olfactory marker protein (OMP) and the thickness of olfactory epithelium on the 28th day after injection. SPSS 23.0 software was used for statistical analysis. Results: Before injection, all mice in each group had no olfactory dysfunction. At the 7th, 14th, 21st and 28th days after injection, the food finding time of mice in group C was shorter than that in group B, and the difference was statistically significant ((175.88±100.50) s vs (266.73±46.83) s, (132.00±84.62) s vs (264.10±48.50) s, (103.57±77.43) s vs (197.43±69.78) s, (67.79±32.54) s vs (176.63±61.06) s, all P<0.05), but food finding time of mice in group B and C was longer than that in group A (the food finding time of group A at the 7th, 14th, 21st and 28th days after injection was (27.13±5.36) s, (25.83±7.28) s, (23.13±2.72) s, (26.63±7.60) s, respectively, all P<0.05). At the 28th day after olfactory training, the number of OMP positive cells in group B and C were fewer than that in group A, and the difference was statistically significant ((108.00±28.19)/HP vs (288.22±84.06)/HP, (199.33±58.55)/HP vs (288.22±84.06)/HP, all P<0.05). The number of OMP positive cells in group C were higher than that in group B (P<0.05). The number of OMP positive cells had negative correlation with food finding time (r=-0.886, P<0.01). As for the thickness of the olfactory epithelium, the thickness of group B was thinner than that in group A and C, and the difference was statistically significant ((59.57±31.27) μm vs (114.55±40.70)μm vs (90.54±37.72) μm, all P<0.05). Conclusion: Olfactory training can accelerate the recovery of olfactory function in 3-MI-induced olfactory impaired mice.

Rhodium-Catalyzed Branched and Enantioselective Direct α-Allylic Alkylation of Simple Ketones with Alkynes

Herein, we report the first direct branched-selective α-allylic alkylation of simple ketones with alkynes under rhodium and secondary amine cooperative catalysis. Through a rhodium-hydride-catalyzed allylic substitution pathway, a series of valuable γ,δ-unsaturated ketones are obtained with excellent regioselectivity in an atom-economic and byproduct-free manner. With a chiral BIPHEP ligand, high enantioselectivity has been achieved for this transformation.

Palladium-catalyzed diastereo- and enantioselective allylic alkylation of oxazolones with 1,3-dienes under base-free conditions

Herein, we report a highly diastereo- and enantioselective allylic alkylation of oxazolones with 1,3-dienes by palladium-hydride catalyst under base-free conditions.

The Abscopal Effect of Stereotactic Radiotherapy and Immunotherapy: Fool's Gold or El Dorado?

An 'abscopal' effect if often used to refer to distant tumour regression after localised irradiation. Since the first report of the abscopal effect in the 1950s, well-documented cases with radiotherapy alone are very rare. It is widely accepted that the immune response plays an important role in the abscopal effect, although the mechanism is still unclear. With the recent success of cancer immunotherapy, there is growing interest in combining immunotherapy with radiotherapy to boost abscopal response rates. Compared with conventional radiotherapy, stereotactic ablative radiotherapy (SABR) not only delivers ablative dose to the tumour, but may also induce robust immune responses. In this review we examine studies that combine SABR and immunotherapy. We review the preclinical rationale for SABR and immunotherapy combinations, the case for and against abscopal effects, and the current landscape of clinical trials.

Diagnostic Value of Contrast-Enhanced Spectral Mammography in Comparison to Magnetic Resonance Imaging in Breast Lesions

Objective

The aim of this study was to evaluate the diagnostic value between contrast-enhanced spectral mammography (CESM) and breast magnetic resonance imaging (MRI) in breast disease.

Methods

Two hundred thirty-five patients who were suspected of having breast abnormalities by clinical examination or mammography underwent CESM and MRI examination. Using histopathologic results as the criterion standard, the diagnostic performance of CESM and MRI was investigated. The areas under receiver operating characteristic curves were applied to analyze diagnostic efficiency. The Pearson correlation coefficients between CESM versus pathology and MRI versus pathology were calculated.

Results

Two hundred sixty-three breast lesions were found in 235 patients, in which 177 were malignant and 86 were benign. By evaluating the diagnostic value, sensitivity, positive predictive value, negative predictive value, and false-negative rate from CESM examination were comparable to those from MRI (91.5%, 94.7%, 83.7%, and 8.5% vs 91.5%, 90.5%, 82.1%, and 8.5%). Importantly, the accuracy and the specificity were higher for CESM than those for MRI (81% and 89.5% vs 80.2% and 71.7%), whereas the false-positive rate was lower (10.5% vs 19.8%). The areas under receiver operating characteristic curves of CESM and MRI were 0.950 and 0.939, displaying the equivalent diagnostic efficiency (P = 0.48).

For the agreement between measurements, mean tumor sizes were 3.1 cm for CESM and 3.4 cm for MRI compared with 3.2 cm on histopathologic results. The Pearson correlation coefficient of CESM versus histopathology (r = 0.774, P = 0.000) was consistent with MRI versus histopathology (r = 0.771, P = 0.000).

Conclusions

Our results show better accuracy, specificity, and false-positive rate of CESM in breast cancer detection than MRI. Contrast-enhanced spectral mammography displayed a good correlation with histopathology in assessing the lesion size of breast cancer, which is consistent with MRI.

Three-dimensional genome structures of single sensory neurons in mouse visual and olfactory systems

Sensory neurons in the mouse eye and nose have unusual chromatin organization. Here we report their three-dimensional (3D) genome structure at 20-kilobase (kb) resolution, achieved by applying our recently developed diploid chromatin conformation capture (Dip-C) method to 409 single cells from the retina and the main olfactory epithelium of adult and newborn mice. The 3D genome of rod photoreceptors exhibited inverted radial distribution of euchromatin and heterochromatin compared with that of other cell types, whose nuclear periphery is mainly heterochromatin. Such genome-wide inversion is not observed in olfactory sensory neurons (OSNs). However, OSNs exhibited an interior bias for olfactory receptor (OR) genes and enhancers, in clear contrast to non-neuronal cells. Each OSN harbored multiple aggregates of OR genes and enhancers from different chromosomes. We also observed structural heterogeneity of the protocadherin gene cluster. This type of genome organization may provide the structural basis of the 'one-neuron, one-receptor' rule of olfaction.

Branched-Selective Direct α-Alkylation of Cyclic Ketones with Simple Alkenes

Herein, we describe an intermolecular direct branched-selective α-alkylation of cyclic ketones with simple alkenes as the alkylation agents. Through an enamine-transition metal cooperative catalysis mode, the α-alkylation is realized in an atom- and step-economic manner with excellent branched selectivity for preparing β-branched ketones. Employment of a pair of bulky Brønsted acid and base as additives is responsible for enhanced efficiency. Promising enantioselectivity (74 % ee) has been obtained. Experimental and computational mechanistic studies suggest that a pathway through alkene migratory insertion into the Ir-C bond followed by C-H reductive elimination is involved for the high branched selectivity.