Molecular Epidemiology of SARS-associated Coronavirus, Beijing

Viral adaptation to the host may be occurring under selective immune pressure

Genomic variation, environmental adaptation and feralization in ramie, an ancient fiber crop

Feralization is an important evolutionary process, but the mechanisms behind it remain poorly understood. Here, we use the ancient fiber crop, ramie (Boehmeria nivea (L.) Gaudich.) as a model to investigate genomic changes associated with both domestication and fertilization. We first produced a chromosome-scale de novo genome assembly of feral ramie and investigated structural variations between feral and domesticated ramie genomes. Next, 915 accessions from 20 countries were gathered, comprising cultivars, major landraces, feral populations and wild progenitor. Based on whole genome resequencing of these accessions, the most comprehensive ramie genomic variation map to date was constructed. Phylogenetic, demographic, and admixture signal detection analyses indicate that feral ramie is of exoferal or exo-endo origin, i.e., descended from hybridization between domesticated ramie and wild progenitor or ancient landraces. Feral ramie has greater genetic diversity than wild or domesticated ramie, and genomic regions affected by natural selection during feralization are different from those under selection during domestication. Ecological analyses showed that feral and domesticated ramie have similar ecological niches which are substantially different from the niche of the wild progenitor, and three environmental variables were associated with habitat-specific adaptation in feral ramie. Our findings advance our understanding of feralization, providing a scientific basis for the excavation of new crop germplasm resources and offering novel insights into the evolution of feralization in nature

Identification, evaluation, and application of the genomic-SSR loci in ramie

To provide a theoretical and practical foundation for ramie genetic analysis, simple sequence repeats (SSRs) were identified in the ramie genome and employed in this study. From the 115 369 sequences of a specific-locus amplified fragment library, a type of reduced representation library obtained by high-throughput sequencing, we identified 4774 sequences containing 5064 SSR motifs. SSRs of ramie included repeat motifs with lengths of 1 to 6 nucleotides, and the abundance of each motif type varied greatly. We found that mononucleotide, dinucleotide, and trinucleotide repeat motifs were the most prevalent (95.91%). A total of 98 distinct motif types were detected in the genomic-SSRs of ramie. Of them, The A/T mononucleotide motif was the most abundant, accounting for 41.45% of motifs, followed by AT/TA, accounting for 20.30%. The number of alleles per locus in 31 polymorphic microsatellite loci ranged from 2 to 7, and observed and expected heterozygosities ranged from 0.04 to 1.00 and 0.04 to 0.83, respectively. Furthermore, molecular identity cards (IDs) of the germplasms were constructed employing the ID Analysis 3.0 software. In the current study, the 26 germplasms of ramie can be distinguished by a combination of five SSR primers including Ibg5-5, Ibg3-210, Ibg1-11, Ibg6-468, and Ibg6-481. The allele polymorphisms produced by all SSR primers were used to analyze genetic relationships among the germplasms. The similarity coefficients ranged from 0.41 to 0.88. We found that these 26 germplasms were clustered into five categories using UPGMA, with poor correlation between germplasm and geographical distribution. Our study is the first large-scale SSR identification from ramie genomic sequences. We have further studied the SSR distribution pattern in the ramie genome, and proposed that it is possible to develop SSR loci from genomic data for population genetics studies, linkage mapping, quantitative trait locus mapping, cultivar fingerprinting, and as genetic diversity studies

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Treatment of Epilepsy with Bipolar Electro-coagulation: An Analysis of Cortical Blood Flow and Histological Change in Temporal Lobe

Background: Bipolar electro-coagulation has a reported efficacy in treating epilepsy involving functional cortex by pure electro-coagulation or combination with resection. However, the mechanisms of bipolar electro-coagulation are not completely known. We studied the acute cortical blood flow and histological changes after bipolar electro-coagulation in 24 patients with intractable temporal lobe epilepsy. Methods: Twenty-four patients were consecutively enrolled, and divided into three groups according to the date of admission. The regional cortical blood flow (rCBF), electrocorticography, the depth of cortex damage, and acute histological changes (H and E staining, neuronal staining and neurofilament (NF) staining) were analyzed before and after the operation. The t-test analysis was used to compare the rCBF before and after the operation. Results: The rCBF after coagulation was significantly reduced (P < 0.05). The spikes were significantly reduced after electro-coagulation. For the temporal cortex, the depth of cortical damage with output power of 2-9 W after electro-coagulation was 0.34 ± 0.03, 0.48 ± 0.06, 0.69 ± 0.06, 0.84 ± 0.09, 0.98 ± 0.08, 1.10 ± 0.11, 1.11 ± 0.09, and 1.22 ± 0.11 mm, respectively. Coagulation with output power of 4-5 W completely damaged the neurons and NF protein in the molecular layer, external granular layer, and external pyramidal layer. Conclusions: The electro-coagulation not only destroyed the neurons and NF protein, but also reduced the rCBF. We concluded that the injuries caused by electro-coagulation would prevent horizontal synchronization and spread of epileptic discharges, and partially destroy the epileptic focus

Preparation,characterization and NO/NO₂ catalytic reduction performance of MnO₂-Fe₂O₃-CeO₂/Al₂O₃ nanocatalysts with different manganese contents

Reducing NOx emission in the exhaust gas under the extremely low temperature of engine cold start was important for the ecological environment and human health.MnO2 has high catalytic activity for NOx in the low temperature range, which is a promising nanocatalyst.The intrinsic relationship between the surface structural characteristics and denitrification activity of MnO2-Fe2O3-CeO2/Al2O3 nanocatalysts produced by ultrasonic assisted coprecipitation method with different manganese contents was discussed. The results show that when the manganese content is 15%(mass fraction), the nanocatalyst has the largest specific surface area and the smallest grain size. At the same time, the distribution of active substances is the most uniform. Meanwhile, the crystallinity of metal oxides is suppressed, and Mn, Fe and Ce are in the best coexistence state, which can promote the enrichment of chemisorption oxygen. The catalytic oxidation of NO to NO2 improves the reaction rate of fast SCR, and the NO2 conversion reaches 88.5% at 50 ℃. Optimizing manganese content is an extremely effective method to improve the structure-activity relationship of catalytic materials and promote the performance of NO preoxidation and fast SCR reaction

Comparison of Talaromyces marneffei Infection in Human Immunodeficiency Virus-positive and Human Immunodeficiency Virus-negative Patients from Fujian, China

Background: Talaromyces (Penicillium) marneffei (TM) is an emerging dimorphic human pathogenic fungus that is endemic to Southeast Asia. TM mostly occurs as an opportunistic infection in patients with human immunodeficiency virus (HIV). The objective of this study was to compare the clinical and laboratory parameters of patients with TM infections who were HIV-positive and HIV-negative and to assess therapies and outcomes. Methods: This was a retrospective analysis of 26 patients diagnosed with disseminated TM infection from September 2005 to April 2014 at Fujian Provincial Hospital, China. Results: Patients with TM infection tend to present with fever, weight loss, and anemia. The time from symptom onset to confirmed diagnosis was greater for HIV-negative patients (n = 7; median: 60 days, range: 14–365 days) than for HIV-positive patients (n = 19; median: 30 days, range: 3–90 days, Mann–Whitney U = 31.50, P= 0.041). HIV-negative patients were more likely to have dyspnea (57.1% vs. 5.3%, χ2 = 8.86, P= 0.010), low neutrophil count (Mann–Whitney U = 27.00, P= 0.029), high CD4 count (Mann–Whitney U = 0.00, P= 0.009), and high lymphocyte count (Mann–Whitney U = 21.00, P= 0.009). There were no significant differences in other demographic, clinical, or biochemical characteristics. Among all the patients, 12 HIV-positive patient and 1 HIV-negative patient received amphotericin and fluconazole treatment, 9 of whom improved, 1 died, 2 had kidney damage, 1 had hypokalemia due to exceeded doses. Conclusions: HIV-negative patients with TM infections tend to have a longer diagnostic interval, a higher percentage of dyspnea, higher levels of CD4 and lymphocytes, and lower neutrophil counts than TM infection in HIV-positive patients. Treatment programs with amphotericin and fluconazole are mostly effective

The Efficacy of Urinary Continence in Patients Undergoing Robot-Assisted Radical Prostatectomy with Bladder-Prostatic Muscle Reconstruction and Bladder Neck Eversion Anastomosis

Background and Objectives: To evaluate the efficacy of bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis in the recovery of urinary continence after robot-assisted radical prostatectomy (RARP). Materials and Methods: From January 2020 to May 2022, 69 patients who underwent RARP in our hospital were recruited. Thirty-seven patients underwent RARP with the Veil of Aphrodite technique (control group). On the basis of the control group, 32 patients underwent bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis during RARP (observation group). The recovery of urinary continence was followed up at 24 h and 1, 4, 12, and 24 weeks after catheter removal. Results: There were no significant differences in operative time (127.76 ± 21.23 min vs. 118.85 ± 24.71 min), blood loss (118.27 ± 16.75 mL vs. 110.77 ± 19.63 mL), rate of leakage (3.13% vs. 2.70%), rate of positive surgical margin (6.25% vs. 10.81%), or postoperative Gleason score [7 (6–8) vs. 7 (7–8)] between the observation group and the control group (p > 0.05). After catheter removal, the rates of urinary continence at 24 h, 1 week, 4 weeks, 12 weeks, and 24 weeks were 46.88%, 68.75%, 84.38%, 90.63%, and 93.75% in the observation group, respectively. Meanwhile, the rates of urinary continence in the control group were 21.62%, 37.84%, 62.16%, 86.49%, and 91.89%, respectively. There was a significant difference between the two groups (p = 0.034), especially at 24 h, 1 week, and 4 weeks after catheter removal (p Conclusions: Bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis were beneficial to the recovery of urinary continence after RARP, especially early urinary continence

Rapid Qualitative and Quantitative Determination of Seven Valuable Taxanes from Various Taxus Species by UFLC-ESI-MS and UFLC-DAD

The distribution and level of yew constituents vary with species and tissues. In this study, a rapid and valid method incorporating ultra-fast liquid chromatography (UFLC) with MS and UV detection was developed for simultaneous determination of paclitaxel and its six semisynthesis precursors in needles and hair roots from various Taxus species. All target analytes could be identified by comparing their retention times as well as UV and MS spectra with authentic standards, while seven valuable taxanes in botanical samples can be rapidly determined by UFLC-DAD with excellent sensitivity. Analysis of more than one hundred yew samples from nine species showed significant variations in distribution and content of seven evaluated taxanes. Thus, different developmental schemes should be used for better utilization of various yew resources