Brush-like gold nanowires-anchored g-C3N4 nanosheets with tunable geometry for ultrasensitive and regenerative SERS detection of gaseous molecules

Strapping plasmonic substrate with a reliable ability to anchor molecules and achieve reproducible result provides trustworthy opportunities for flourishing surface-enhanced Raman scattering (SERS) technique. Herein, a facile controllable in-situ anisotropic growth strategy was exploited to anchor gold nanowires (Au NWs) onto two-dimensional g-C₃N₄ nanosheets (g-C₃N₄/Au NWs), facilitating a sensitive and recyclable SERS sensor for gaseous analytes. Benefiting from the attractive enrichment effect of the brush-like surface formed by numerous small Au NWs as well as their rich nanotips-mediated enhancement capability, the hybrid substrate showed an outstanding performance in SERS-based detection of trace 4-Aminothiophenol (4-ATP) molecules, demonstrating a monitoring limitation down to 10^-8 M even in atmosphere. Satisfyingly, under visible light illumination, the efficient green photocatalytic ability derived from the g-C₃N₄ supporting matrix rendered reusable capability for the substrate, whose SERS signal was kept at a persistent high level throughout 6 cycles. Attributed to the narrow line width of SERS spectrum, the 4-ATP assay under the interference of 2-naphthalenethiol (2-NAT) was acquired in gas phase and the dependable recovery rates from 85.4 to 93.9% were confirmed as well. Thanks to the intriguing features including excellent sensitivity and recyclability, the g-C₃N₄/Au NWs substrate proposed here will pave the way toward the potential application of SERS technique in multiplexed gaseous detection.

[Enterostomy based on abdominal wall tension and fascial locking: a theory of preventing stoma complications and parahernia]

No consensus on standardized technique of enterostomy creation has been made meanwhile high heterogeneity of surgical procedure exists in 'stoma creation' chapters of textbooks or atlases of colorectal surgery. The present article reviews the anatomy of tendinous aponeurotic fibers which is crucial for abdominal wall tension and integrity. Through empirical practice we hypothesize a procedure of enterostomy creation basied on abdominal wall tension plus anchor suture for fascia fixation which could theoretically decrease short-term stoma complication rates and long-term parastomal hernia rates. Surgical techniques are as followed: (1) preoperative stoma site mark for de-functioning ileostomy should be positioned at the lateral border of rectus abdominis muscle (RAM) to decrease the difficulty of stoma reversal and for permanent colostomy should be placed overlying the RAM to promote adhesion; (2)Optimal circular removal or lineal opening of skin, and avoid dissection of subcutaneous tissue; (3) Lineal dissection of natural strong fascia (rectus sheath) at stoma site and blunt separation of muscular fibers. The tunnel of the fascia should be made with appropriate size without undue tension. To prevent the formation of dead space, additional suturing at fascia layer is unnecessary. (4) Anchor suture for fascia fixation at two ends of fascia opening could be considered to avoid delayed fascia disruption and parastomal hernia. (5) After pull-through of ileum or colon loop, 4-8 interrupted seromuscular sutures could be placed to attach loop to skin. For ileostomy, self-eversion of mucosa can be successful in vast majority of cases and a Brooke ileostomy is not necessary. The efficacy and safety of this procedure should be tested in future trials.

An Interpretable Deep Embedding Model for Few and Imbalanced Biomedical Data

In healthcare, training examples are usually hard to obtain (e.g., cases of a rare disease), or the cost of labelling data is high. With a large number of features ( p) be measured in a relatively small number of samples ( N), the "big p, small N" problem is an important subject in healthcare studies, especially on the genomic data. Another major challenge of effectively analyzing medical data is the skewed class distribution caused by the imbalance between different class labels. In addition, feature importance and interpretability play a crucial role in the success of solving medical problems. Therefore, in this paper, we present an interpretable deep embedding model (IDEM) to classify new data having seen only a few training examples with highly skewed class distribution. IDEM model consists of a feature attention layer to learn the informative features, a feature embedding layer to directly deal with both numerical and categorical features, a siamese network with contrastive loss to compare the similarity between learned embeddings of two input samples. Experiments on both synthetic data and real-world medical data demonstrate that our IDEM model has better generalization power than conventional approaches with few and imbalanced training medical samples, and it is able to identify which features contribute to the classifier in distinguishing case and control.

[Bacterial community diversity in Dermatophagoides farinae using high-throughput sequencing]

OBJECTIVE

To investigate the bacterial community diversity in Dermatophagoides farinae.

METHODS

Laboratory-cultured D. farinae was collected, and the composition of microbial communities was determined by sequence analyses of the V4 region in the bacterial 16S ribosomal RNA (16S rRNA) gene on an Illumina PE250 high-throughput sequencing platform. Following quality control and filtering of the raw sequence files, valid reads were obtained and subjected to operational taxonomic units (OTU) clustering and analysis of the composition of microbial communities and alpha diversity index using the Usearch software, Silva database, and Mothur software.

RESULTS

A total of 187 616 valid reads were obtained, and 469 OTUs were clustered based on a sequence similarity of more than 97%. OTU annotation showed that the bacteria in D. farinae belonged to 26 phyla, 43 classes, 100 orders, 167 families and 284 genera. The bacteria in D. farinae were mainly annotated to five phyla of Proteobacteria, Firmicutes, Bacteroidota, Actinobacteriota, and Acidobacteriota, with Proteobacteria as the dominant phylum, and mainly annotated to five dominant genera of Ralstonia, norank-f-Mitochondria, Staphylococcus and Sphingomonas, with Wolbachia identified in the non-dominant genus.

CONCLUSIONS

A high diversity is identified in the composition of the bacterial community in D. farinae, and there are differences in bacterial community diversity and abundance among D. farinae.

[Comparison of the efficacy and safety of 2 low-dose rituximab regimens in the second-line treatment of primary immune thrombocytopenia in children]

Objective: To compare the efficacy and safety of 2 low-dose rituximab regimens in the treatment of children with primary immune thrombocytopenia (ITP). Methods: A total of 90 ITP children admitted to the Hematology Oncology Center of Beijing Children's Hospital from January 2018 to March 2021 were enrolled in this prospective cohort study. In the single-dose group, rituximab was given with a single dose of 375 mg/m² (maximum dose 600 mg). In the 4-dose group, rituximab was given with a dose of 100 mg weekly (if body weight of the patient ≥ 30 kg, increase dosage to 200 mg weekly) for 4 weeks. Wilcoxon Mann-Whitney test, Chi-square test and Fisher's exact test were used to analyze the difference in efficacy, safety and treatment burden between two groups. Results: Among the 90 children, 41 were male and 49 were female, and the age of medication was 6.8 (4.1,10.0) years. There were 27 cases in the single-dose group and 63 cases in the 4-dose group.There were no significant differences in overall response rate, complete response rate and partial response rate between the single-dose group and 4-dose group (41% (11/27) vs. 33% (21/63), 26% (7/27) vs. 19% (12/63), 15% (4/27) vs. 14%(9/63), χ²=0.45, 0.54, 0.00, all P>0.05). The single-dose group was earlier to get overall response than the 4-dose group (1 (1, 1) vs. 3 (2, 6) weeks, Z=-3.24, P=0.001). There were no significant differences in the sustained response rate, the overall response rate in 1 year, the complete response rate in 1 year, and the partial response rate in 1 year between the single-dose group and the 4-dose group (33% (9/27) vs. 30% (19/63), 30% (8/27) vs. 24% (15/63), 19% (5/27) vs. 14% (9/63), 11% (3/27) vs. 10% (6/63), χ²=0.09, 0.34, 0.04, 0.00, all P>0.05). There were no significant differences in the duration of overall response, recurrence rate within half a year and one year, recurrence time and rate of adverse events between the single-dose group and 4-dose group (all P>0.05). The number of hospitalizations, the duration of hospital stays and the dosage of the single-dose group were significantly lower than those of the 4-dose group (1 (1, 1) vs. 4 (4, 4) times, 5 (4, 7) vs. 8 (5, 8) d, 400 (250, 500) vs. 400 (400, 800) mg, Z=-8.67, -3.03, -4.05, all P<0.05). Conclusions: The single-dose rituximab regimen is comparable to 4-dose rituximab regimen in effectiveness and safety for treatment of children ITP, but more economical and convenient. The single-dose rituximab regimen is more suitable for the second-line treatment of children ITP.

Characterization of biochar-derived organic matter extracted with solvents of differing polarity via ultrahigh-resolution mass spectrometry

In recent years, biochar, a porous carbon-based material, has gained attention for its application prospects in contaminated soil remediation and soil improvement. Biochar-derived organic matter has a key role in influencing the migration and transformation of soil elements and pollutants. However, existing research concerning the molecular characteristics of biochar-derived organic matter is limited. Here, we used four polar solvents - dichloromethane (CH₂Cl₂), acetone (CH₃COCH₃), methanol (CH₃OH), and distilled water (H₂O) - to extract organic matter from soybean straw biochar and wheat straw biochar by accelerated solvent extraction (ASE). We characterized the extracts using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). We found considerable differences in organic matter according to the extraction solvents; such differences were related to the polarity of the solvent, as well as intermolecular forces between the solvent and organic matter. CH₃OH extracted the most biochar-extractable organic matter components because CH₃OH can weaken or destroy oxygen bridge bonds in biochar and form hydrogen bonds with small-molecule organic compounds. CH₃OH and H₂O have strong extraction capacity for compounds containing heteroatoms. CH₂Cl₂-extractable organic matter is relatively labile and bioavailable, while CH₃OH- and H₂O-extractable organic matters are relatively stable. In addition, the binding capacity of biochar-derived organic matter for minerals and pollutants differed among fractions, in part because of differences in molecular weight, atomic O/C and H/C ratios, heteroatom distribution, and biomolecular compounds present in biochar-derived organic matter. The findings in this study help to select appropriate extractants to analyze biochar-derived organic matter for various research purposes, and provides a theoretical basis for biochar-based remediation of contaminated soil.

[Associations between early onset of puberty and obesity types in children: Based on both the cross-sectional study and cohort study]

OBJECTIVE

To explore and analyze the relationship between early onset of puberty and different types of obesity in children, by combining large sample cross-sectional survey data with long-term longitudinal cohort data, so as to provide clues for further clarifying the health hazards of early onset of puberty and obesity prevention and control.

METHODS

The research data were from the cross-sectional survey data of seven provinces(autonomous regions, municipalities) in China and the cohort data of adolescent development in Xiamen. The study first found the association between early onset of puberty and obesity by Logistic regression on the cross-sectional data, and then used Poisson regression to analyze the association between early puberty initiation and various types of obesity risk.

RESULTS

In the study, 43 137 and 1 266 children were included in the cross-sectional survey and cohort survey respectively. The cross-sectional study found that among the girls aged 10-13 years, compared with the girls of the same age who did not start puberty, the body mass index (BMI)-Z score of the girls in the puberty start group was 0.5-0.8 higher, and the waist circumference Z score was 0.4-0.7 higher, and the risk of various types of obesity was higher. At the same time, the early onset of puberty was positively correlated with simple obesity, central obesity and compound obesity, the OR (95%CI) were 1.86 (1.42-2.44), 1.95 (1.65-2.32) and 1.86 (1.41-2.45), respectively. No significant association was found in boys. According to the cohort data, in girls, the risk of simple obesity was 6.00 times [RR (95%CI): 6.00 (1.07-33.60)], the risk of central obesity was 3.30 times [RR (95%CI): 3.30 (1.22-8.92)], and the risk of compound obesity was 5.76 times [RR (95%CI): 5.76 (1.03-32.30)], compared with the group without early puberty initiation, while no association between early puberty initiation and obesity was found in boys.

CONCLUSION

Based on the cross-sectional survey and longitudinal cohort survey, it is confirmed that the early onset of puberty in girls may increase the risk of simple obesity, central obesity and compound obesity, while there is no significant correlation between puberty onset and obesity in boys.

Risk factors and predictive scoring system for twice or more strokes in patients with cerebral small vessel disease

Objectives To explore the independent risk factors of twice or more strokes in patients with cerebral small vessel disease, and to construct a predictive scoring system. Methods A retrospective study was carried out in Tangshan, Hebei Province, China. Patients with cerebral small vessel disease suffered from acute stroke and admitted to Neurology Department of Tangshan Gongren Hospital from January 2020 to June 2021 were collected and grouped according to whether they had a previous stroke history. Binary logistic regression models were used to investigate the independent risks for the occurrence of twice or more strokes in patients with cerebral small vessel disease, assigned scores to each factor, then established and evaluated the predictive efficacy of the predictive scoring system. Results A total of 531 patients were included. Regression analysis showed that age, hypertension, diabetes, intracranial arterial stenosis, and total cerebral small vessel disease burden were independent risk factors. On the basis of each regression coefficient, a 10-point predictive scoring system selected the highest Jordon index as the cut-off value, which was 4 points. And the area under the receiver operating characteristic curve was 0.842 (95 %CI: 0.796~0.893, P＜0.001). Conclusions The predictive scoring system based on age, hypertension, diabetes, intracranial arterial stenosis, and total cerebral small vessel disease burden can effectively predict whether patients with cerebral small vessel disease are tend to be onset with twice or more strokes.