[Analysis of time for diagnosis of nontuberculous mycobacterial lung disease and its associated factors in a tuberculosis-designated hospital in Shanghai].

Objective: To investigate the pathogenic characteristics, bacteriological diagnosis time and its associated factors among patients with nontuberculous mycobacterial (NTM) lung disease in a large tuberculosis-designated hospital in Shanghai from 2020 to 2021, in order to improve diagnosis efficiency and formulate precision treatment. Methods: On the basis of the Tuberculosis Database in Shanghai Pulmonary Hospital, NTM patients diagnosed by the Department of Tuberculosis between January 2020 and December 2021 were screened. Demographic, clinical and bacterial information were retrospectively collected. Chi-square test, paired-sample nonparametric test and logistic regression model were used to analyze the factors associated with the diagnosis time of NTM lung disease. Results: A total of 294 patients with bacteriologically confirmed NTM lung disease were included in this study, 147 males and 147 females with a median age of 61(46, 69) years. Of them, 227 (77.2%) patients had comorbidity of bronchiectasis. Species identification results showed that Mycobacterium Avium-Intracellulare Complex was the main pathogen of NTM lung disease (56.1%), followed by Mycobacterium kansasii (19.0%) and Mycobacterium abscessus (15.3%). Species such as Mycobacterium xenopi and Mycobacterium malmoense were rarely identified, accounting for a total proportion of only 3.1%. Positive culture rates for sputum, bronchoalveolar lavage fluid and puncture fluid were 87.4%, 80.3% and 61.5%, respectively. Paired-sample analysis showed that the positive rate of sputum culture was significantly higher than that of smear microscopy (87.1% vs. 48.4%, P<0.01), while no statistical difference was observed between sputum and bronchoalveolar lavage fluid on positive culture rate (78.7% vs. 77.3%, P>0.05). Patients with cough or expectoration were observed with 4.04-fold (95%CI 1.80-9.05) or 2.95-fold (95%CI 1.34-6.52) higher probability of positive sputum culture, compared to those without. Regarding bronchoalveolar lavage fluid, female or patients with bronchiectasis had a 2.82-fold (95%CI 1.16-6.88) or 2.38-fold (95%CI 1.01-5.63) higher probability to achieve a positive culture. The median time to diagnosis of NTM lung disease was 32 (interquartile range: 26-42) days. The results of multivariable analysis showed that patients with symptom of expectoration (aOR=0.48, 95%CI 0.29-0.80) needed a shorter diagnosis time in comparison with patients without expectoration. With Mycobacterium Avium-Intracellulare Complex as a reference, lung disease caused by Mycobacterium abscessus needed shorter diagnosis time (aOR=0.43, 95%CI 0.21-0.88), whereas those caused by rare NTM species were observed to require a longer diagnosis time (aOR=8.31, 95%CI 1.01-68.6). Conclusion: The main pathogen causing NTM lung disease in Shanghai was Mycobacterium Avium-Intracellulare Complex. Sex, clinical symptoms and bronchiectasis had an impact on the positive rate of mycobacterial culture. The majority of patients in study hospital were timely diagnosed. Clinical symptoms and NTM species were associated with the bacteriological diagnosis time of NTM lung disease.

Risk factors for prolongation of ileostomy closure operation.

OBJECTIVE: Understanding factors for prolonged operative time is essential for surgery. This study aims at identifying the factors related to prolonged ileostomy closure operation time. PATIENTS AND METHODS: The data of 88 patients who underwent ileostomy reversal in the Department of Gastrointestinal Surgery of Jiaxing First Hospital between January 2018 and October 2021 were retrospectively analyzed. Prolonged operation time was defined as operative time >65 minutes. The Chi-square test was used to compare data between patients with normal operative time (≤65 minutes) and patients with prolonged operative time. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with prolonged ileostomy closure operation time. RESULTS: Among the 88 patients (mean age: 62.78 years), median ileostomy retention time was 127.50 (range: 61.00-1,192.00) days. The operation time ranged from 35.00 minutes to 125.00 minutes. Prolonged ileostomy closure time occurred in 41 (46.6%) patients. In univariate analysis, the factors associated with prolonged operation time were body mass index (BMI) ≥25 kg/m2, previous history of abdominal surgery, and manual suture. History of serious complications after the primary operation was associated with shorter operation time. In multivariate analysis, the independent risk factors for prolonged operation time were BMI ≥25 kg/m2 (OR = 4.552, 95% CI: 1.369-15.136, p = 0.013), previous history of abdominal surgery (OR = 4.377, 95% CI: 1.394-13.739, p = 0.011), and manual suture (OR = 3.941, 95% CI: 1.181-13.154, p = 0.026). CONCLUSIONS: Overweight, previous history of abdominal surgery, and manual suture appear to be risk factors for prolonged operative time for ileostomy closure.

Association of Subjective Cognitive Decline with Risk of Cognitive Impairment and Dementia: A Systematic Review and Meta-Analysis of Prospective Longitudinal Studies.

BACKGROUND: Subjective cognitive decline (SCD) as an early pathological manifestation of brain aging has become more prevalent among older adults. OBJECTIVES: We aimed to investigate the associations of subjective cognitive decline (SCD) with the combined risk of cognitive impairment and dementia. DESIGN: We performed a systematic review and meta-analysis via searching Embase, PubMed and Cochrane electronic databases from January 1 st 1970 to June 4th, 2020. SETTING: Prospective cohort studies Participants: Healthy individuals were recruited from community, clinics and population. MEASUREMENTS: Healthy individuals with SCD were classified into exposure groups, while those without were considered as the reference group. Adjusted relative risks (RR) were estimated in a random-effects model. Both primary and subgroup analyses were conducted. RESULTS: Of 28,895 identified studies, 21 studies containing 22 cohorts were eligible for inclusion in the meta-analysis. SCD increased the risk of subsequent cognitive disorders (RR=2.12, 95% confidence intervals [CI] =1.75-2.58, I2=87%, P<0.01). To be specific, SCD conferred a 2.29-fold excess risk for cognitive impairment (RR=2.29, 95% CI=1.66-3.17, I2=83%, P<0.01) and a 2.16-fold excess risk for dementia (RR=2.16, 95% CI=1.63-2.86, I2=81%, P<0.01). In subgroup analyses, participants with SCD in the subgroup of 65-75 years old, long-education (>15 years) subgroup and subgroup of clinics showed a higher risk of developing objective cognitive disorders. CONCLUSIONS: SCD is associated with an increased combined risk of cognitive impairment and incident dementia and should be considered a risk factor for objective cognitive disorders.

[Isolation and biological characteristics on Yersinia pestis phage YP060].

OBJECTIVE: To isolate and identify the characteristics of Yersinia pestis phage YP060 from mice nests in Yunnan plague focus. METHODS: Phage YP060 was isolated from Yunnan plague focus by double-layer agar plate method with attenuated vaccine Yersinia pestis strain EV76 as the host bacterium. Phage particle was observed under the electron microscope while biological properties of phage YP060 including lytic capacity, host spectrum, optimal multiplicity of infection (MOI), one-step growth curve, sensitivity to temperature, pH, ultraviolet ray and chloroform etc. were identified. RESULTS: The particles of phage YP060 presented tadpoles-like features, with optimal multiplicity of infection as 0.1. Latent period and burst period appeared as 50 min and 80 min, respectively. The phage endured the temperature between 30-50 ℃, and it contained a stronger lysis activities in a range of pH 5 to 10. Phage YP060 was sensitive to ultraviolet rays but insensitive to chloroform while presented special lysic ability to Yersinia pestis. CONCLUSION: Yersinia pestis phage YP060 was isolated for the first time from mice nests in plague natural focus in China. Our findings related to narrow host spectrum and stronger lysis activities.

Undulatory locomotion of Caenorhabditis elegans on wet surfaces.

The physical and biomechanical principles that govern undulatory movement on wet surfaces have important applications in physiology, physics, and engineering. The nematode Caenorhabditis elegans, with its highly stereotypical and functionally distinct sinusoidal locomotory gaits, is an excellent system in which to dissect these properties. Measurements of the main forces governing the C. elegans crawling gait on lubricated surfaces have been scarce, primarily due to difficulties in estimating the physical features at the nematode-gel interface. Using kinematic data and a hydrodynamic model based on lubrication theory, we calculate both the surface drag forces and the nematode's bending force while crawling on the surface of agar gels within a preexisting groove. We find that the normal and tangential surface drag coefficients during crawling are ∼222 and 22, respectively, and the drag coefficient ratio is ∼10. During crawling, the calculated internal bending force is time-periodic and spatially complex, exhibiting a phase lag with respect to the nematode's body bending curvature. This phase lag is largely due to viscous drag forces, which are higher during crawling as compared to swimming in an aqueous buffer solution. The spatial patterns of bending force generated during either swimming or crawling correlate well with previously described gait-specific features of calcium signals in muscle. Further, our analysis indicates that one may be able to control the motility gait of C. elegans by judiciously adjusting the magnitude of the surface drag coefficients.

Undulatory swimming in viscoelastic fluids.

The effects of fluid elasticity on the swimming behavior of the nematode Caenorhabditis elegans are experimentally investigated by tracking the nematode's motion and measuring the corresponding velocity fields. We find that fluid elasticity hinders self-propulsion. Compared to Newtonian solutions, fluid elasticity leads to up to 35% slower propulsion. Furthermore, self-propulsion decreases as elastic stresses grow in magnitude in the fluid. This decrease in self-propulsion in viscoelastic fluids is related to the stretching of flexible molecules near hyperbolic points in the flow.