[Analysis of biofilm-forming ability and drug resistance for Hypervirulent Klebsiella pneumoniae].

Investigate the biofilm-forming ability and drug resistance of Hypervirulent Klebsiella pneumoniae (HvKP) to provide scientific basis for the treatment of HvKP-infection. A total of 96 Klebsiella pneumoniae strains isolated from clinical infection specimens in Changsha Central Hospital from January to December in 2021 were retrospectively collected, and the clinical data of patients were collected. The string test preliminarily distinguished between HvKP and classic Klebsiella pneumoniae (CKP). The biofilm-forming ability of clinical strains of Klebsiella pneumoniae (KP) was determined by microplate method. The Vitek 2 Compact automatic microbial identification/drug sensitivity analysis system was used for bacterial identification and drug sensitivity test. The clinical data of patients, biofilm forming ability and drug resistance in the HvKP group and those in the CKP group were compared and analyzed. The results showed that a total of 20 strains of HvKP were isolated from 96 non-repetitive KP, and the detection rate was 20.8%. HvKP mainly come from respiratory specimens, up to 75.0%.The prevalence of hepatobiliary diseases and the infection rate of multiple sites in patients with HvKP infection were higher than those in patients with CKP infection, and the difference was statistically significant(χ2=5.184,7.488;P=0.023,0.006).There was no significant difference between the two groups in terms of gender, age, ICU admission, hypertension, diabetes, coronary heart disease, lung disease, urinary system disease, central nervous system disease and laboratory test indexes (all P>0.05).17 (85.0%) strains of HvKP can form biofilm, including 2 strains with weak biofilm-forming ability (10.0%), 10 strains with moderate biofilm-forming ability (50.0%) and 5 strains with strong biofilm-forming ability (25.0%). Among the 76 CKP, 71 (93.4%) could form biofilm, including 13 (17.1%) with weak biofilm-forming ability, 30(39.5%) with moderate biofilm-forming ability and 28 (36.8%) with strong biofilm-forming ability. There was no significant difference in biofilm-forming ability between HvKP and CKP (χ2=1.470,P=0.225).The overall resistance rate of HvKP was not high, but a multi-resistant HvKP resistant to carbapenems was found. The detection rate of multi-resistant HvKP (5.0%) was lower than that of multi-resistant CKP (28.9%), and the difference was statistically significant (χ2=4.984, P=0.026).The resistance rate of HvKP to piperacillin/tazobactam, aztreonam, ciprofloxacin, levofloxacin, ceftazidime, cefepime, tobramycin, minocycline, doxycycline, and compound sulfamethoxazole was lower than that of CKP, and the difference was statistically significant (all P<0.05). In conclusion, most of hypervirulent Klebsiella pneumoniae can form biofilm in this study, but the difference of biofilm-forming ability is not obvious compared with classic Klebsiella pneumoniae. HvKP maintains high sensitivity to commonly used antibacterial drugs, but the drug resistance monitoring of the bacteria cannot be ignored.

[HbA1c comparison and diagnostic efficacy analysis of multi center different glycosylated hemoglobin detection systems].

Objective: Compare and analyze the results of the domestic Lanyi AH600 glycated hemoglobin analyzer and other different detection systems to understand the comparability of the detection results of different detectors, and establish the best cut point of Lanyi AH600 determination of haemoglobin A1c (HbA1c) in the diagnosis of diabetes. Methods: Multi center cohort study was adopted. The clinical laboratory departments of 18 medical institutions independently collected test samples from their respective hospitals from March to April 2022, and independently completed comparative analysis of the evaluated instrument (Lanyi AH600) and the reference instrument HbA1c. The reference instruments include four different brands of glycosylated hemoglobin meters, including Arkray, Bio-Rad, DOSOH, and Huizhong. Scatter plot was used to calculate the correlation between the results of different detection systems, and the regression equation was calculated. The consistency analysis between the results of different detection systems was evaluated by Bland Altman method. Consistency judgment principles: (1) When the 95% limits of agreement (95% LoA) of the measurement difference was within 0.4% HbA1c and the measurement score was≥80 points, the comparison consistency was good; (2) When the measurement difference of 95% LoA exceeded 0.4% HbA1c, and the measurement score was≥80 points, the comparison consistency was relatively good; (3) The measurement score was less than 80 points, the comparison consistency was poor. The difference between the results of different detection systems was tested by paired sample T test or Wilcoxon paired sign rank sum test; The best cut-off point of diabetes was analyzed by receiver operating characteristic curve (ROC). Results: The correlation coefficient R2 of results between Lanyi AH600 and the reference instrument in 16 hospitals is≥0.99; The Bland Altman consistency analysis showed that the difference of 95% LoA in Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180) was -0.486%-0.325%, and the measurement score was 94.6 points (473/500); The difference of 95% LoA in the Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant II) was -0.727%-0.612%, and the measurement score was 89.8 points; The difference of 95% LoA in the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT) was -0.231%-0.461%, and the measurement score was 96.6 points; The difference of 95% LoA in the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT) was -0.469%-0.479%, and the measurement score was 91.9 points. The other 14 hospitals, Lanyi AH600, were compared with 4 reference instrument brands, the difference of 95% LoA was less than 0.4% HbA1c, and the scores were all greater than 95 points. The results of paired sample T test or Wilcoxon paired sign rank sum test showed that there was no statistically significant difference between Lanyi AH600 and the reference instrument Arkray HA8180 (Z=1.665,P=0.096), with no statistical difference. The mean difference between the measured values of the two instruments was 0.004%. The comparison data of Lanyi AH600 and the reference instrument of all other institutions had significant differences (all P<0.001), however, it was necessary to consider whether it was within the clinical acceptable range in combination with the results of the Bland-Altman consistency analysis. The ROC curve of HbA1c detected by Lanyi AH600 in 985 patients with diabetes and 3 423 patients with non-diabetes was analyzed, the area under curve (AUC) was 0.877, the standard error was 0.007, and the 95% confidence interval 95%CI was (0.864, 0.891), which was statistically significant (P<0.001). The maximum value of Youden index was 0.634, and the corresponding HbA1c cut point was 6.235%. The sensitivity and specificity of diabetes diagnosis were 76.2% and 87.2%, respectively. Conclusion: Among the hospitals and instruments currently included in this study, among these four hospitals included Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180), Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant Ⅱ), the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT), and the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT), the comparison between Lanyi AH600 and the reference instruments showed relatively good consistency, while the other 14 hospitals involved four different brands of reference instruments: Arkray, Bio-Rad, DOSOH, and Huizhong, Lanyi AH600 had good consistency with its comparison. The best cut point of the domestic Lanyi AH600 for detecting HbA1c in the diagnosis of diabetes is 6.235%.

HIV-1 genotype is independently associated with immunodeficiency progression among Chinese men who have sex with men: an observational cohort study.

OBJECTIVES: HIV-1 genetic diversity is increasing among men who have sex with men (MSM) in China, but the association of HIV-1 genotype with disease progression remains to be elucidated. METHODS: We collected data in an observational longitudinal cohort study of 860 HIV-1-infected MSM in Guangzhou, China between January 2008 and March 2017. Kaplan-Meier analysis and Cox proportional hazard model were used to predict the time from HIV-1 diagnosis to immunodeficiency progression (CD4 cell count < 200 cells/µl) as well as adjusted hazard ratio (aHR). RESULTS: CRF01_AE and HIV-1 subtype B infection were associated with higher percentage of patients progressed to immunodeficiency and higher incidence of immunodeficiency than infection with CRF07_BC or CRF55_01B. Compared with CRF07_BC, the time from HIV-1 diagnosis to immunodeficiency were different among the major HIV-1 genotypes, which ranked as follows, in descending order: CRF07_BC (7.03 years) > CRF55_01B (5.71 years, P = 0.014; aHR 3.752, P = 0.0923) > CRF01_AE (5.18 years, P < 0.001; aHR 4.733, P = 0.0152). HIV-1 genotype, viral load and baseline CD4 T-cell count were three independent variables associated with disease progression. CONCLUSIONS: Our results confirm differential rates of immunodeficiency progression as a function of HIV-1 genotype. The impact of HIV-1 genotype on HIV epidemics, patient management and prevention should be further investigated.

Randomised clinical trial: Tong-Xie-Yao-Fang granules versus placebo for patients with diarrhoea-predominant irritable bowel syndrome.

BACKGROUND: Tong-Xie-Yao-Fang (TXYF) is a Chinese herbal formula for treating chronic diarrhoea accompanied by abdominal pain. The results were inconsistent in previous trials examining its effect. AIM: To study the efficacy of TXYF granules for treating diarrhoea-predominant irritable bowel syndrome (IBS-D). METHODS: We performed a double-blind, placebo-controlled randomised trial and enrolled 160 participants with IBS-D. The participants had VAS scores ≥3 cm in IBS-D global symptoms and ≥2 days in a week with abdominal pain and loose stools (Bristol score 5, 6 or 7). They were randomly assigned to received TXYF or placebo during a treatment period of 4 weeks, and they were followed up for 8 weeks after treatment. The primary outcome was adequate relief of IBS-D global symptoms for at least 2 of 4 weeks during weeks 1-4. Secondary outcomes included mean weekly VAS scores of IBS-D major symptoms, mean weekly stool frequency, mean weekly Bristol score, and adverse events. RESULTS: 155 of 160 patients completed the trial. We found a significantly higher rate of adequate relief of global symptoms in TXFY group during weeks 1 to 4 (57.5% vs 37.5%, χ2 = 5.6391, P = 0.017); logistic regression analysis showed a similar result (OR 2.2, 95% CI 1.2-4.4, P = 0.016). Most of the secondary outcomes showed superiority of TXYF over placebo in weekly assessment from week 3 to week 7. The adverse event rate was low in both groups (3.8% vs 3.8%, P = 1.000). CONCLUSION: During a 4 week trial, TXFY granules were superior to placebo in controlling symptoms of IBS-D.

The effect of meconium exposure on the expression and differentiation of amniotic fluid mesenchymal stem cells.

BACKGROUND: The goal of this study was to determine if exposure to meconium would alter the phenotype of amniotic fluid mesenchymal stem cells (AF-MSCs) and the ability of these cells to be differentiated into distal airway type cells. METHODS: Meconium was collected, lyophilized and resuspended in PBS at 3 different concentrations (high, medium, and low). AF-MSCs were cultured in the presence of this meconium suspension for 8 hours and then analyzed for changes in gene expression. Additionally, AF-MSCs exposed to meconium were differentiated for 14 days using modified small airway growth medium (mSAGM) and gene expression was determined. As a spontaneous differentiation control, meconium exposed AF-MSCs were cultured in amniotic fluid stem cell medium (AF medium). RESULTS: After 8 hours of exposure in culture, AF-MSCs had increased expression of distal airway genes aquaporin 5 (AQP5) and surfactant protein c (SPC) when cultured in AF medium containing meconium. These gene expression levels were similar to that of AF-MSCs that were differentiated in mSAGM for 14 days. Furthermore, there was an up regulation of pluripotency genes NANOG and OCT4 in response to low meconium concentration for 8 hours. Following 14 days of culture in mSAGM, there was an upregulation of TTF1, SPC and AQP5 expression in the control, as well as in the low and medium meconium exposed groups indicating that these cells were still able to be differentiated. High meconium concentration did, however, appear to influence the level of distal airway gene expression after 14 days in mSAGM. After 14 days in AF medium, there was significant downregulation in pluripotency and mesenchymal markers as well as distal airway gene expression in all groups. CONCLUSION: The phenotype of AF-MSCs is modulated by meconium exposure; however, the cells were still able to differentiate into distal airway gene and protein expression. This result supports the hypothesis that progenitor cells exist in the amniotic fluid and the presence of meconium may affect their initial phenotype. However, these cells were still able to be differentiated to a distal lung phenotype.

Image multiplexing and encryption using the nonnegative matrix factorization method adopting digital holography.

In this paper, a joint multiple-image encryption and multiplexing system, which utilizes both the nonnegative matrix factorization (NMF) scheme and digital holography, is proposed. A number of images are transformed into noise-like digital holograms, which are then decomposed into a defined number of basis images and a corresponding weighting matrix using the NMF scheme. The determined basis images are similar to the digital holograms and appear as noise-like patterns, which are then stored as encrypted data and serve as the lock in an encryption system. On the other hand, the column vectors in the weighting matrix serve as the keys for the corresponding plain images or the addresses of the multiplexed images. Both the increased uniformity of the column weighting factors and the parameters used in the digital holography enhance the security of the distributed keys. The experimental results show that the proposed method can successfully perform multiple-image encryption with high-level security.

[Determination of Hair Shafts by InnoTyper® 21 Kit].

OBJECTIVES: To explore the application value of InnoTyper® 21 kit in forensic practice. METHODS: Samples of hair shafts and saliva were collected from 8 unrelated individuals. Template DNA was extracted by AutoMate Express™ forensic DNA automatic extraction system. DNA was amplified by InnoTyper® 21 kit and AmpFℓSTR™ Identifiler™ Plus kit, respectively, and then the results were compared. RESULTS: After the amplification by InnoTyper® 21 kit, complete specific genotyping could be detected from the saliva samples, and the peak value of genotyping profiles of hair shafts without sheath cells was 57-1 219 RFU. Allelic gene deletion could be found sometimes. When amplified by AmpFℓSTR™ Identifiler™ Plus kit, complete specific genotyping could be detected from the saliva samples, and the specific fragment was not detected in hair shafts without sheath cells. CONCLUSIONS: The InnoTyper® 21 kit has certain application value in the cases of hair shafts without sheath cells.

Genomic structure of the mouse PP4 gene: a developmentally regulated protein phosphatase.

Protein phosphatases play important roles in the control of various cellular processes. Here, we report the cloning and characterization of the murine cDNA and genomic DNA encoding the serine/threonine protein phosphatase 4 (PP4), also called PPX. While the nucleotide sequences of murine and human PP4 are distinct, their amino acid sequences are identical. We have analyzed the protein, cDNA and genomic PP4 sequences to provide insight into the structure, function and potential regulation of PP4. Genomic Southern blots demonstrated the conservation of PP4 across species. Using Northern blotting and in situ hybridization, we have examined the expression of PP4 in murine embryos and adult tissues. In adult tissues, PP4 was expressed at high levels in the testis, kidney, liver, and lung, and at lower levels in virtually all tissues. PP4 was differentially expressed in murine embryos at different developmental stages, suggesting that PP4 is a developmentally regulated protein phosphatase.

Involvement of hematopoietic progenitor kinase 1 in T cell receptor signaling.

Hematopoietic progenitor kinase 1 (HPK1), a mammalian Ste20-related serine/threonine protein kinase, is a hematopoietic-specific upstream activator of the c-Jun N-terminal kinase. Here, we provide evidence to demonstrate the involvement of HPK1 in T cell receptor (TCR) signaling. HPK1 was activated and tyrosine-phosphorylated with similar kinetics following TCR/CD3 or pervanadate stimulation. Co-expression of protein-tyrosine kinases, Lck and Zap70, with HPK1 led to HPK1 activation and tyrosine phosphorylation in transfected mammalian cells. Upon TCR/CD3 stimulation, HPK1 formed inducible complexes with the adapters Nck and Crk with different kinetics, whereas it constitutively interacted with the adapters Grb2 and CrkL in Jurkat T cells. Interestingly, HPK1 also inducibly associated with linker for activation of T cells (LAT) through its proline-rich motif and translocated into glycolipid-enriched microdomains (also called lipid rafts) following TCR/CD3 stimulation, suggesting a critical role for LAT in the regulation of HPK1. Together, these results identify HPK1 as a new component of TCR signaling. T cell-specific signaling molecules Lck, Zap70, and LAT play roles in the regulation of HPK1 during TCR signaling. Differential complex formation between HPK1 and adapters highlights the possible involvement of HPK1 in multiple signaling pathways in T cells.

Pulmonary surfactant activity after severe steam inhalation injury in rabbits.

Lung water content, Pao2, surface tension (in terms of hysteresis) and lecithin content of both bronchial irrigation fluid and lung homogenates were determined after severe steam inhalation injury in rabbits. At the time of a decrease in Pao2 and an increase in lung water content there was a moderate fall in pulmonary surfactant activity; as shown by a progressive decrease in the area of the hysteresis loop and a decrease of the lecithin content in both bronchial irrigation fluid and lung homogenate. It is proposed that a fall in pulmonary surfactant activity plays an important role in the pathogenesis of pulmonary oedema after inhalation injury. Successive determinations of lecithin content and/or surface tension of bronchial irrigation fluid are recommended as early diagnostic and prognostic aids in severe inhalation injury.