bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic and balanced regulation of the thrABC operon gene for efficient synthesis of L-threonine
Authors: Hao Ruxin , Wang Sumeng , Jin Xin , Yang Xiaoya , Qi Qingsheng , Liang Quanfeng 
Published: March 2023

L-threonine is an essential amino acid used widely in food, cosmetics, animal feed and medicine. The thrABC operon plays an important role in regulating the biosynthesis of L-theronine. In this work, we systematically analyzed the effects of separating thrAB and thrC in different proportions on strain growth and L-threonine production in Escherichia coli firstly. The results showed that higher expression of thrC than thrAB enhanced cell growth and L-threonine production; however, L-threonine production decreased when the thrC proportion was too high. The highest L-threonine production was achieved when the expression intensity ratio of thrAB to thrC was 3:5. Secondly, a stationary phase promoter was also used to dynamically regulate the expression of engineered thrABC. This strategy improved cell growth and shortened the fermentation period from 36 h to 24 h. Finally, the acetate metabolic overflow was reduced by deleting the ptsG gene, leading to a further increase in L-threonine production. With these efforts, the final strain P2.1-2901ΔptsG reached 40.06 g/L at 60 h fermentation, which was 96.85% higher than the initial control strain TH and the highest reported titer in shake flasks. The maximum L-threonine yield and productivity was obtained in reported fed-batch fermentation, and L-threonine production is close to the highest titer (127.30 g/L). In this work, the expression ratio of genes in the thrABC operon in E. coli was studied systematically, which provided a new approach to improve L-threonine production and its downstream products.
Preterm birth leads to a decreased number of differentiated podocytes and accelerated podocyte differentiation
Authors: Zhang Lulu , Chen Zhihui , Gao Qi , Liu Ge , Zheng Jun , Ding Fangrui 
Published: March 2023

Preterm birth was previously identified as a high-risk factor for the long-term development of chronic kidney disease. However, the detailed pattern of podocyte (PD) changes caused by preterm birth and the potential mechanism underlying this process have not been well clarified. In present study, a rat model of preterm birth was established by delivery of pups 2 days early and podometric methods were applied to identify the changes in PDs number caused by preterm birth. In addition, single-cell RNA sequencing (scRNA-seq) and subsequent bioinformatic analysis were performed in the preterm rat kidney to explore the possible mechanism caused by preterm birth. As results, when the kidney completely finished nephrogenesis at the age of 3 weeks, a reduction in the total number of differentiated PDs in kidney sections was detected. In addition, 20 distinct clusters and 12 different cell types were identified after scRNA-seq in preterm rats (postnatal day 2) and full-term rats (postnatal day 0). The numbers of PDs and most types of inherent kidney cells were decreased in the preterm birth model. In addition, 177 genes were upregulated while 82 genes were downregulated in the PDs of full-term rats compared with those of preterm rats. Further functional GO analysis revealed that ribosome-related genes were enriched in PDs from full-term rats, and kidney development-related genes were enriched in PDs from preterm rats. Moreover, known PD-specific and PD precursor genes were highly expressed in PDs from preterm rats, and pseudotemporal analysis showed that PDs were present earlier in preterm rats than in full-term rats. In conclusion, the present study showed that preterm birth could cause a reduction in the number of differentiated PDs and accelerate the differentiation of PDs.
Prevalence, multiple antibiotic resistance and virulence profile of methicillin-resistant Staphylococcus aureus (MRSA) in retail poultry meat from Edo, Nigeria
Authors: Igbinosa Etinosa O. , Beshiru Abeni , Igbinosa Isoken H. , Ogofure Abraham G. , Ekundayo Temitope C. , Okoh Anthony I. 
Published: March 2023

IntroductionStaphylococcus aureus causes staphylococcal food poisoning and several difficult-to-treat infections. The occurrence and dissemination of methicillin-resistance S. aureus (MRSA) in Nigeria is crucial and well documented in hospitals. However, findings on MRSA from meat in the country are yet to be adequately reported. The current study determined the prevalence, virulence profile and antibiogram characteristics of MRSA from a raw chicken product from retail outlets within Edo.MethodsA total of 368 poultry meat samples were assessed for MRSA using a standard culture-based approach and characterized further using a molecular method. The antimicrobial susceptibility profile of the isolates was determined using the disc diffusion method. The biofilm profile of the isolates was assayed via the crystal violet microtitre-plate method. Virulence and antimicrobial resistance genes were screened using polymerase chain reaction via specific primers.ResultsOf the samples tested, 110 (29.9%) were positive for MRSA. All the isolates were positive for deoxyribonuclease (DNase), coagulase and beta-hemolysis production. Biofilm profile revealed 27 (24.55%) weak biofilm formers, 18 (16.36%) moderate biofilm formers, and 39 (35.45%) strong biofilm formers. The isolates harboured 2 and ≤17 virulence genes. Enterotoxin gene profiling revealed that 100 (90.9%) isolates harboured one or more genes. Resistance against the tested antibiotics followed the order: tetracycline 64(58.2%), ciprofloxacin 71(64.6%), trimethoprim 71(64.6%) and rifampin 103(93.6%). A total of 89 isolates were multidrug-resistant, while 3 isolates were resistant to all 22 antibiotics tested. The isolates harboured antimicrobial-resistant determinants such as methicillin-resistant gene (mecA), tetracycline resistance genes (tetK, tetL), erythromycin resistance genes (ermA, ermC), trimethoprim resistance gene (dfrK). All the staphylococcal cassette chromosome mec (SCCmec) IVa and SCCmec V positive isolates harboured the Panton-Valentine Leukocidin Gene (PVL).ConclusionIn conclusion, S. aureus was resistant to commonly used antibiotics; a concern to public health concerning the transmission of these pathogens after consuming these highlight the significance of antimicrobial and enterotoxigenic monitoring of S. aureus in food chains.
Impact of exercise on pulmonary artery pressure in patients with heart failure using an ambulatory pulmonary artery pressure monitor
Authors: Khedraki Rola , Abraham Jacob , Jonsson Orvar , Bhatt Kunjan , Omar Hesham R. , Bennett Mosi , Bhimaraj Arvind , Guha Ashrith , McCann Patrick , Muse Evan D. , Robinson Monique , Sauer Andrew J. , Cheng Andrew , Bagsic Samantha , Fudim Marat , Heywood J. Thomas , Guglin Maya 
Published: March 2023

BackgroundIn this multicenter prospective study, we explored the relationship between pulmonary artery pressure (PAP) at rest and in response to a 6-min walk test (6MWT) in ambulatory patients with heart failure (HF) with an implantable PAP sensor (CardioMEMS, Abbott).MethodsBetween 5/2019 and 2/2021, HF patients with a CardioMEMS sensor were recruited from seven sites. PAP was recorded in the supine and seated position at rest and in the seated position immediately post-exercise.ResultsIn our cohort of 66 patients, mean age was 70 ± 12 years, 67% male, left ventricular ejection fraction (LVEF) &lt; 50% in 53%, mean 6MWT distance was 277 ± 95 meters. Resting seated PAPs were 31 ± 15 mmHg (systolic), 13 ± 8 mmHg (diastolic), and 20 ± 11 mmHg (mean). The pressures were lower in the seated rather than the supine position. After 6MWT, the pressures increased to PAP systolic 37 ± 19 mmHg (p &lt; 0.0001), diastolic 15 ± 10 mmHg (p = 0.006), and mean 24 ± 13 mmHg (p &lt; 0.0001). Patients with elevated PAP diastolic at rest (&gt;15 mmHg) demonstrated a greater increase in post-exercise PAP.ConclusionThe measurement of PAP with CardioMEMS is feasible immediately post-exercise. Despite being well-managed, patients had severely limited functional capacity. We observed a significant increase in PAP with ambulation which was greater in patients with higher baseline pressures.
Preoperative optimization of cardiac valve patients’ expectations: Study protocol of the randomized controlled ValvEx-trial
Authors: Horn Nicole , Gärtner Laura , Rastan Ardawan J. , Andrási Térezia B. , Lenz Juliane , Böning Andreas , Salzmann-Djufri Miriam , Puvogel Ulrike , Genovese Maria , Kus Sibel , Rief Winfried , Salzmann Stefan 
Published: March 2023

IntroductionComplete recovery after surgery depends on psychological factors such as preoperative information, expectations, and surgery-associated anxiety. Prior studies have shown that even a short preoperative psychological intervention aiming at optimized expectations (EXPECT) can improve postoperative outcomes in coronary artery bypass patients. However, this intervention may benefit only a small subgroup of heart surgery patients since implementing preoperative psychological interventions into the daily clinical routine is difficult due to the additional time and appointments. It is unclear whether the EXPECT intervention can be shortened and whether heart valve patients would also benefit from interventions that optimize patients’ expectations. The multicenter ValvEx trial aims (i) to adapt an effective preoperative psychological intervention (EXPECT) to make it brief enough to be easily integrated into the preoperative routine of heart valve patients and (ii) to examine if the adapted preoperative psychological intervention improves the subjectively perceived illness-related disability (PDI) up to 3 months after surgery.Materials and analysisIn two German university hospitals, N = 88 heart valve patients who undergo heart surgery are randomized into two groups [standard of care (SOC) vs. standard of care plus interventional expectation manipulation (SOC and EXPECT)] after baseline assessment. Patients in the EXPECT group additionally to standard of care participate in the preoperative psychological intervention (30–40 min), focusing on optimizing expectations and have two booster-telephone calls (4 and 8 weeks after the surgery, approx. 15 min). Both groups have assessments again on the evening before the surgery, 4 to 6 days, and 3 months after the surgery.DiscussionThe trial demonstrates excellent feasibility in the clinical routine and a high interest by the patients.Ethics and disseminationThe Ethics Committees of the Department of Medicine of the Philipps University of Marburg and the Department of Medicine of the University of Giessen approved the study protocol. Study results will be published in peer-reviewed journals and presented at congresses.Clinical trial registrationClinicalTrials.gov, identifier NCT04502121.
Numerical simulation study on the influence of air leakage on oxygen concentration in goafs of fully mechanized caving mining with shallow buried and large mining height
Authors: Zhu Xingpan , Wen Hu 
Published: March 2023

In order to reveal the influence of air leakage on oxygen concentration in goafs of fully mechanized caving mining with a shallow buried and high mining height, the air leakage of No.122108 working face in Caojiatan coal mine in different seasons was tested by the SF6 tracer gas test method. Based on the result of the air leakage test, the “three zones” of spontaneous combustion in the goaf were simulated using Ansys Fluent fluid dynamics software, and the simulated result was compared with that of the field test. The result shows that the vertical air leakage of the working face is serious, the wind speed is high, and the air leakage rate is up to 86.96%. The air leakage rate is higher in winter and lower in summer. The air leakage intensity decreases from the air inlet side to the air return side through the middle of the goaf. The range of the oxidation heating zone of the goaf is 98–245 m on the air inlet side and 33–96 m on the air return side. The numerical simulation result is well consistent with the field test data. The research conclusion can guide fire prevention and the extinguishing of No.122108 working face and lay a foundation for the prevention and control of spontaneous fire in goafs of fully mechanized caving mining with a shallow buried and high mining height.
Cognition and BDNF levels in prediabetes and diabetes: A mediation analysis of a cross-sectional study
Authors: Sumbul-Sekerci Betul , Sekerci Abdusselam , Pasin Ozge , Durmus Ezgi , Yuksel-Salduz Zeynep Irem 
Published: March 2023

AimClinical and epidemiological studies suggest links between dementias and Type 2 diabetes (T2DM). The underlying mechanisms of diabetes-related cognitive impairment are largely unknown. This study aims to investigate the role of BDNF in cognitive impairment in prediabetes and T2DM.MethodsThe study included 68 patients with prediabetes (preDM), 96 patients with T2DM, and 65 healthy controls. The cognitive function of the patients was evaluated with the Montreal Cognitive Assessment (MoCA) test and serum BDNF levels were measured by Elisa. The MoCA scores and BDNF levels were compared between diabetes groups after adjusting for age, gender, and education using ANCOVA. The role of BDNF in the diabetes-related cognitive impairment was investigated through mediation analysis.ResultsPatients with T2DM had significantly lower cognitive performance, particularly in memory. Diabetes was found to be a predictor of both cognitive impairment and BDNF levels. A significant increase in serum BDNF levels was observed in patients with T2DM. However, the mediator role of BDNF in the pathology of cognitive impairment in diabetes was not determined.ConclusionCognitive impairment is prevalent in patients with T2DM and should be included in routine screening for complications. The results of the mediation analysis suggest that although BDNF is a biomarker affected by T2DM and cognition, it does not play a mediator role between cognitive impairment and diabetes.
Robotic-assisted laparoscopic adrenalectomy (RARLA): What advantages and disadvantages compared to retroperitoneal laparoscopic adrenalectomy (RLA)?
Authors: Li Xuwen , Xiao Song , Yu Yue , Liu Wei , Xi Haibo , Wang Gongxian , Zhou Xiaochen 
Published: March 2023

ObjectiveTo explore the advantages and disadvantages of robot-assisted laparoscopic adrenalectomy compared with retroperitoneal laparoscopic adrenalectomy.MethodsA total of 101 patients with adrenal tumors who received retroperitoneal laparoscopic adrenalectomy (RLA) (n=75) or robot-assisted laparoscopic adrenalectomy (RARLA) (n=26) in our hospital from January 2021 to December 2021 were retrospectively collected. Patients’ demographics, tumor characteristics, and perioperative indicators were compared. Statistical analysis was performed using t-test for continuous variables and Pearson chi-square test or Fisher’s exact test for categorical variables.ResultsWe found that blood loss in the RARLA group was significantly less than that in the RLA group (66.9 ± 35.5 ml vs 91.5 ± 66.1 ml, p = 0.020). Gastrointestinal function recovery time in RARLA group was significantly less than that in RLA group (19.9 ± 6.9 hours vs 32.0 ± 9.0 hours, p &lt; 0.001). However, the operation time, drainage tube placement time, post-operative hospital stay in the RARLA group were significantly longer compared with the RLA group (149.6 ± 53.4 mins vs 118.7 ± 41.2 mins, p = 0.003; 4.9 ± 2.0 days vs 3.6 ± 1.1 days, p = 0.004; 6.4 ± 1.8 days vs 4.6 ± 1.6 days, p &lt; 0.001). The hospitalization expense in the RARLA group is significantly higher than that in the RLA group (59284 ± 8724 RMB¥ vs 39785 ± 10126 RMB¥, p &lt; 0.001). We found that there was no significant difference in the incidence of postoperative complications between the two groups. However, the pathological types of the two groups were significantly different. Patients in the RLA group had a higher proportion of adrenocortical adenoma, while patients in the RARLA group had a higher proportion of pheochromocytoma.ConclusionCompared with traditional laparoscopic adrenalectomy, robot-assisted laparoscopic adrenalectomy can significantly reduce intraoperative blood loss and accelerate postoperative gastrointestinal recovery. It is committed to studying how to reduce the hospitalization time and hospitalization cost of RARLA, which can make RARLA more widely used.
Spatial and temporal changes in land and water resources on the northern slopes of the Tianshan mountains from the perspective of “production-living-ecological space”
Authors: Xu Xingang , Tian Hao , Yang Guang , Li Xiaolong , He Xinlin , Li Yi , Gao Yongli , Li Fadong , Li Pengfei , Liu Bing , Xue Lianqing 
Published: March 2023

The rapidly growing social demand for water and land, along with increasingly constraining economic and social development, have intensified the conflicts between regional production, living, and ecological spaces (PLES). Water and land resources have become major obstacles to long-term growth in arid and semi-arid regions. Therefore, we propose a scenario-based framework for a production, living, and ecological spaces water resource assessment, integrating patch-generating land use simulation (PLUS), Shared Socioeconomic Pathways (SSPs), and multiple regression equations to analye the spatial and temporal variability of these resources on the northern slopes of the Tianshan Mountains (NSTM) and assess the future development of water resources. The results show: 1) from 2000 to 2020, land use types on the northern slopes of the Tianshan Mountains were dominated by ecological land, which decreased to 11,793 km2; production and domestic land use increased. Water for production and ecological use accounted for approximately 93% and a minor proportion of the total water use, respectively. 2) Production land is mainly influenced by population density and Gross Domestic Product (GDP), living land by population density, and ecological land by precipitation and topographic factors. 3) The PLUS model had good applicability, with a kappa coefficient, overall accuracy, and FoM of 0.81, 0.88, and 0.28, respectively. 4) The total water use in the northern slopes of the Tianshan Mountains will increase under all three scenarios between 2030 and 2050, but by varying degrees. Production water use accounts for the most significant proportion (93%), with its use decreasing by 305 million m3 under the SSP3 scenario. Domestic water use shows a slow increase under all three scenarios. Further development of the northern slopes of the Tianshan Mountains should take account of regional ecological vulnerability, and water use for production should be controlled based on existing water resources and ecological capacity to reduce pressure on the environment and provide essential ecological protection and sustainable development.
Increased whitebark pine (Pinus albicaulis) growth and defense under a warmer and regionally drier climate
Authors: Kichas Nickolas E. , Pederson Gregory T. , Hood Sharon M. , Everett Richard G. , McWethy David B. 
Published: March 2023

IntroductionTree defense characteristics play a crucial role in modulating conifer bark beetle interactions, and there is a growing body of literature investigating factors mediating tree growth and resin-based defenses in conifers. A subset of studies have looked at relationships between tree growth, resin duct morphology and climate; however, these studies are almost exclusively from lower-elevation, moisture-limited systems. The relationship between resin ducts and climate in higher-elevation, energy-limited ecosystems is currently poorly understood.MethodsIn this study, we: (1) evaluated the relationship between biological trends in tree growth, resin duct anatomy, and climatic variability and (2) determined if tree growth and resin duct morphology of whitebark pine, a high-elevation conifer of management concern, is constrained by climate and/or regional drought conditions.ResultsWe found that high-elevation whitebark pine trees growing in an energy-limited system experienced increased growth and defense under warmer and regionally drier conditions, with climate variables explaining a substantive proportion of variation (∼20–31%) in tree diameter growth and resin duct anatomy.DiscussionOur results suggest that whitebark pine growth and defense was historically limited by short growing seasons in high-elevation environments; however, this relationship may change in the future with prolonged warming conditions.
Comparison of humoral and cellular immune responses between ChAd-BNT heterologous vaccination and BNT-BNT homologous vaccination following the third BNT dose: A prospective cohort study
Authors: Sim Wooho , Kang Hyunhye , Jung Jin , Lee Jihyun , Ko Geon Young , Park Hye-Sun , Choi Jeewan , Park Kinam , Oh Eun-Jee 
Published: March 2023

IntroductionThe differential immune responses after two additional BNT162b2 (BNT) booster doses between ChAdOx1 nCoV-10 (ChAd)-primed and BNT-primed groups have not been elucidated. The aim of this study was to compare vaccine-induced humoral and cellular immune responses and evaluate breakthrough infection between the two vaccination strategies.MethodsIn 221 healthy subjects (111 in the ChAd group), longitudinal immune responses were monitored at 3, 4, and 6 months after the 2nd dose and 1, 3, and 6 months after the 3rd dose. Humoral immunity was measured by two fully automated chemiluminescent immunoassays (Elecsys and Abbott) and a surrogate virus neutralization test (sVNT). Cellular immunity was assessed by two interferon-γ (IFN-γ) release assays (QuantiFERON SARS-CoV-2 and Covi-FERON).ResultsAfter the 2nd dose of BNT vaccination, total antibody levels were higher in the ChAd group, but IgG antibody and sVNT results were higher in the BNT group. Following the 3rd dose vaccination, binding antibody titers were significantly elevated in both groups (ChAD-BNT; 15.4 to 17.8-fold, BNT-BNT; 22.2 to 24.6-fold), and the neutralizing capacity was increased by 1.3-fold in both cohorts. The ChAd-BNT group had lower omicron neutralization positivity than the BNT-BNT group (P = 0.001) at 6 months after the 3rd dose. Cellular responses to the spike antigen also showed 1.7 to 3.0-fold increases after the 3rd dose, which gradually declined to the levels equivalent to before the 3rd vaccination. The ChAd cohort tended to have higher IFN-γ level than the BNT cohort for 3-6 months after the 2nd and 3rd doses. The frequency of breakthrough infection was higher in the ChAd group (44.8%) than in the BNT group (28.1%) (P = 0.0219). Breakthrough infection induced increased humoral responses in both groups, and increase of cellular response was significant in the ChAd group.DiscussionOur study showed differential humoral and cellular immune responses between ChAd-BNT-BNT heterologous and BNT-BNT-BNT homologous vaccination cohorts. The occurrence of low antibody levels in the ChAd-primed cohort in the humoral immune response may be associated with an increased incidence of breakthrough infections. Further studies are needed on the benefits of enhanced cellular immunity in ChAd-primed cohorts.