Volume 72 (2023): Issue 3 (September 2023)

Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the leading causes of morbidity and death in humans worldwide. Some autophagy genes associated with TB and some miRNAs regulating TB have been found, but the identification of autophagy-related genes in M. tuberculosis remains to be explored. Forty-seven autophagy-related genes differentially expressed in TB were identified in this study by analysis of TB-related datasets in the Gene Expression Omnibus (GEO) and autophagy-related genes in the Human Autophagy Database. The potential crucial genes affecting TB were found through the protein-protein interaction (PPI) network, and the possible pathways affected by these genes were verified. Analysis of the PPI network of miRNAs associated with M. tuberculosis infection and their target genes revealed that hsa-let-7, hsa-mir-155, hsa-mir-206, hsa-mir-26a, hsa-mir-30a, and hsa-mir-32 may regulate the expression of multiple autophagy-related genes (MAPK8, UVRAG, UKL2, and GABARAPL1) alone or in combination. Subsequently, Cytoscape was utilized to screen the differentially expressed genes related to autophagy. The hub genes (GABARAPL1 and ULK2) affecting TB were identified. Combined with Gene Set Enrichment Analysis (GSEA), the signaling pathways affected by the hub genes were verified. Finally, we divided TB patients into two subgroups based on autophagy-related genes, and the immune microenvironment of patients in different subgroups was significantly different. Our study found two autophagy-related hub genes that could affect TB and divide TB samples into two subgroups. This finding is of great significance for TB treatment and provides new ideas for exploring the pathogenesis of M. tuberculosis.

To compare the clinical outcomes of linezolid and vancomycin regimens combined with one-stage surgery in treating traumatic osteomyelitis of the limbs caused by methicillin-resistant Staphylococcus aureus (MRSA) infection. A retrospective study was performed to analyze patients with traumatic osteomyelitis of the limbs attributable to MRSA infection. All of these patients received one-stage surgery to debride their wounds, with subsequent implantation of a vancomycin-loaded calcium sulfate artificial bone. Patients received either intravenous linezolid (study group) or vancomycin (control group) during the perioperative period. The postoperative inflammatory markers, renal function, duration of drainage catheter placement, duration of antibiotic administration, length of hospital stay, adverse events, and recurrence of osteomyelitis in these two groups were compared. The study group had a shorter duration of antibiotic administration and length of hospital stay (p < 0.05). There was a significant difference in the incidences of adverse events between the two groups (5.88% and 17.65% in the study and control groups, respectively, p < 0.05). There was no recurrence in either group during the three-year follow-up period. As of year, five after the surgery, one patient in the control group had a recurrence of osteomyelitis. The linezolid regimen should be preferred to the vancomycin regimen in patients with traumatic osteomyelitis of the extremities caused by MRSA infection because the linezolid regimen showed fewer adverse events, shorter periods of antibiotic use, and shorter hospital stay. However, both treatment regimens achieved satisfactory outcomes and warranted further investigations.

We aimed to compare the clinical efficacy of fecal microbiota transplantation (FMT) from the same sex on ulcerative colitis (UC) patients. A total of 272 UC patients were selected in the prospective clinical study, which incorporated four distinct groups, each comprising male and female patients, who were either receiving FMT or placebo, respectively. FMT was performed by sending the gut microbiota of healthy female or male adolescents to the same gender patients via gastroscope three times (one time/three weeks), and a placebo was used with an equal volume of saline. Abdominal pain, diarrhea, thick bloody stool, intestinal mucosal lesion, and Mayo scores were measured. Self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were evaluated. The changes of intestinal flora were detected by the 16S rRNA sequencing. FMT reduced the scores of diarrhea, abdominal pain, mucosal lesion, and Mayo, SAS, and SDS in UC patients compared to the placebo group (p < 0.05). Clostridiales and Desulfovibrionaceae were dominant in gut microbiota from male patients and were reduced after FMT. Meanwhile, the abundance of Prevotella, Lactobacillus, and Bifidobacterium was increased in the male group. Female patients had a higher abundance of Escherichia-Shigella, Desulfovibrionaceae, and Staphylococcaceae before FMT, and it was reduced after FMT. Meanwhile, the abundance of Porphyromonadaceae, Prevotella, Lactobacillus, and Bifidobacterium was increased in the female group. There were no significant changes for the species in the corresponding placebo groups. FMT improved the UC symptoms of male and female patients, which may be associated with different gut microbiota changes.

Human Cytomegalovirus (HCMV) is a leading healthcare problem associated with stillbirth and congenital abnormalities. Determining the seroprevalence and the possible risk factors related to HCMV infections may be a cornerstone in preventing its complications. This cross-sectional study was conducted in Kassala and River Nile States to determine the seroprevalence and risk factors associated with HCMV infection in pregnant women. One hundred eighty-four (n = 184) blood specimens were collected from pregnant women from February 2018 to January 2020. Enzyme-linked immunosorbent assay (ELISA) was used to detect HCMV-specific IgG and IgM antibodies. Socio-demographical characteristics of the women were collected using structured questionnaires. The results showed that HCMV IgG was detected in 170 (92.4%) of the blood specimens, and IgM was detected in 29/93 (31.2%). There was a significant relationship between the history of miscarriage and the presence of IgG and IgM with a p-value = 0.001 and between HCMV IgM and gestational stage (p-value = 0.028). The study found a strikingly high seroprevalence of HCMV infections among pregnant women in the investigated States. This high percentage of illiterate housewives living in rural areas makes it possible to reduce the incidence of HCMV infection in pregnant women by improving their knowledge, attitude, and practice regarding the route of viral transmission, which may reflect in lowering the rate of congenital diseases in their infants.

Uricase (or Urate oxidase), a key enzyme involved in purine metabolism, is commonly used in treating conditions such as gout, hyperuricemia, and tumor lysis syndrome. In this study, a uricase-producing strain (named CSAJ-16) was isolated from the soil sample of Cangshan Mountain, Yunnan Province, China. This strain was identified as Arthrobacter sp. CSAJ-16. Based on the gene sequence alignment, the uricase gene (named aruox) of Arthrobacter sp. CSAJ-16 was amplified and heterologously expressed. The recombinant uricase (ArUOX) was about 32 kDa. The optimal pH and temperature of ArUOX were pH 7 and 20°C, respectively. The ArUOX remained above 50% relative activity after incubation at 37°C for 100 min or at pH 6.0–8.6 for 24 h. Moreover, metal ions such as K⁺, Mg²⁺, Ca²⁺, Ba²⁺ and Pb²⁺ can significantly enhance the activity of ArUOX (> 200%). These enzymatic properties indicate that ArUOX has potential applications in pharmaceutical enzymes and uric acid detection kits.

The study aimed to isolate Lactobacillaceae strains with in vitro hypoglycemic activity and probiotic properties and to determine their antidiabetic abilities in vivo. Lactiplantibacillus plantarum 22, L. plantarum 25, Limosilactobacillus fermentum 11, and L. fermentum 305 with high in vitro hypoglycemic activity were screened from 23 strains of Lactobacillaceae isolated from human feces and identified by 16S rDNA sequencing. The fasting blood glucose (FBG) of the mice was recorded weekly. After 12 weeks, liver, kidney, and pancreas tissues were stained with hematoxylin and eosin (H&E) to observe histomorphology; the inflammatory factors were assayed by Quantitative Real-time PCR; PI3K and AKT were measured by Western blot; the short-chain fatty acids (SCFAs) were determined by LC-MS/MS. Inhibitory activities of L. plantarum 22, L. plantarum 25, L. fermentum 11, and L. fermentum 305 against α-amylase were 62.29 ± 0.44%, 51.81 ± 3.65%, 58.40 ± 1.68%, and 57.48 ± 5.04%, respectively. Their inhibitory activities to α-glucosidase were 14.89 ± 0.38%, 15.32 ± 0.89%, 52.63 ± 3.07%, and 51.79 ± 1.13%, respectively. Their survival rate after simulated gastrointestinal test were 12.42 ± 2.84%, 9.10 ± 1.12%, 5.86 ± 0.52%, and 8.82 ± 2.50% and their adhesion rates to Caco-2 cell were 6.09 ± 0.39%, 6.37 ± 0.28%, 6.94 ± 0.27%, and 6.91 ± 0.11%, respectively. The orthogonal tests of bacterial powders of the four strains showed that the maximum inhibitory activities to α-amylase and α-glucosidase were 93.18 ± 1.19% and 75.33 ± 2.89%, respectively. The results showed that the mixture of Lactobacillaceae could lower FBG, reduce inflammation, and liver, kidney, and pancreas damage, promote PI3K/AKT signaling pathway, and increase the content of SCFAs. The combination of L. plantarum 22, L. plantarum 25, L. fermentum 11, and L. fermentum 305 can potentially improve type 2 diabetes mellitus (T2DM).

A single-arm study was conducted with 10 children aged 2–12 years with severe cow's milk allergy (CMA) requiring complete allergen elimination. Subjects were administered kestose, a prebiotic, at 1 or 2 g/day for 12 weeks. Results of a subsequent oral food challenge (OFC) showed a statistically significant increase in the total dose of cow's milk ingestion (1.6 ml vs. 2.7 ml, p = 0.041). However, the overall evaluation of the OFC results, TS/Pro (total score of Anaphylaxis Scoring Aichi (ASCA)/cumulative dose of protein), showed no statistically significant improvement, although the values were nominally improved in seven out of 10 subjects. The 16S rDNA analysis of fecal samples collected from the subjects revealed a statistically significant increase in the proportion of Faecalibacterium spp. (3.8 % vs. 6.8%, p = 0.013), a type of intestinal bacterium that has been reported to be associated with food allergy. However, no statistically significant correlation was found between Faecalibacterium spp. abundance and the results of the OFC.

The prokaryotic microalga Limnothrix redekei KNUA012 isolated from a freshwater bloom sample from Lake Hapcheon, Hapcheon-gun, South Korea, was investigated for its potential as a biofuel feedstock. Microalgae produce straight-chain alkanes/alkenes from acyl carrier protein-linked fatty acyls via aldehyde decarbonylase (AD; EC 1.2.1.3), which can convert aldehyde intermediates into various biofuel precursors, such as alkanes and free fatty acids. In L. redekei KNUA012, long-chain ADs can convert fatty aldehyde intermediates into alkanes. After heterologous AD expression in Escherichia coli (pET28-AD), we identified an AD in L. redekei KNUA012 that can synthesize various alkanes, such as pentadecane (C₁₅H₃₂), 8-heptadecene (C₁₇H₃₄), and heptadecane (C₁₇H₃₆). These alkanes can be directly used as fuels without transesterification. Biodiesel constituents including dodecanoic acid (C₁₃H₂₆O₂), tetradecanoic acid (C₁₅H₃₀O₂), 9-hexa decenoic acid (C₁₇H₃₂O₂), palmitoleic acid (C₁₇H₃₂O₂), hexadecanoic acid (C₁₇H₃₄O₂), 9-octadecenoic acid (C₁₉H₃₆O₂), and octadecanoic acid (C₁₉H₃₈O₂) are produced by L. redekei KNUA012 as the major fatty acids. Our findings suggest that Korean domestic L. redekei KNUA012 is a promising resource for microalgae-based biofuels and biofuel feedstock.

This work investigated the genetic relationship among Stenotrophomonas maltophilia strains in fecal samples from dairy cows in northeast China and identified the dominant β-lactamase genotype. One hundred and six samples were collected from two randomly selected cow farms in northeast China, and the isolates were identified with MALDI-TOF/MS. Whole-genome sequencing was conducted using Illumina HiSeq 4000-PE150 platform (Illumina, Inc., USA). The antimicrobial resistance genes were detected using CGE services. The phylogenetic analysis of S. maltophilia strains was performed by Roary and MEGA X. In total, 24 S. maltophilia isolates were isolated. The results of resistome analysis showed all S. maltophilia strains carrying bla_L1 gene, which was the only β-lactamase genotype. In addition, the aminoglycoside resistance genes aac(6′)-Iz and aph(3′)-IIc were found. The phylogenetic tree indicated the clonal diversity of S. maltophilia in these two regions and the clonal relatedness of the strains from these regions. This study first investigated the dissemination and characterization of S. maltophilia isolates from dairy cows in northeast China and provided evidence of the potential transmission between two provinces. Furthermore, it indicated bla_L1 was the most prevalent genotype of β-lactamase in these regions.

Fusarium oxysporum is the primary pathogen of blueberry root rot; furthermore, we found that Fusarium commune can also cause root rot in blueberries. Trichoderma spp. is widely used to control plant diseases. We isolated Trichoderma asperellum (TM11) from blueberry rhizosphere soil to explore its control effect and mechanism on F. oxysporum and F. commune. We found that the inhibitory effects of TM11 volatiles and broth metabolites on F. oxysporum were significant, but only F. commune volatile metabolites had a significant inhibitory effect on its growth. Twelve known antimicrobial metabolites were detected from the methanol extract of TM11 fermentation broth by HPLC-MS. TM11 lysed and coiled around the hyphae of F. oxysporum and F. commune. The pot experiment showed that TM11 had significant control effects against F. oxysporum and F. commune, and inoculation of TM11 prior to that of F. oxysporum and F. commune was more effective. The TM11, TM11 and F. oxysporum, or F. commune and distilled water treatments had different effects on the activities of superoxide dismutase, peroxidase and catalase, and the enzyme activity levels exhibited the following order: TM11 > TM11 and F. oxysporum or F. commune > distilled water. The results showed that TM11 provided effective control of blueberry root rot.

Chlamydia felis is an important zoonotic agent for humans and various animals. A recombinase-aided amplification (RAA) assay was developed for detecting C. felis. RAA can be performed in a closed tube at 39°C within 30 min. The detection limit was 10.6 copies of the C. felis plasmid DNA per reaction. No positive signals for other pathogens were detected. The coincidence rate of RAA and conventional PCR was 95.24% (20/21) and 100% (96/96) for positive and negative samples, respectively. The established RAA assay is a simple, rapid, highly sensitive, and specific method for detecting C. felis.