Prevalence and risk factors for colonisation and infection with carbapenem-resistant Enterobacterales in intensive care units: A prospective multicentre study.

OBJECTIVES: This study aimed to investigate the prevalence and risk factors for carbapenem-resistant Enterobacterales colonisation/infection at admission and acquisition among patients admitted to the intensive care unit. RESEARCH METHODOLOGY/DESIGN: A prospective and multicentre study. SETTING: This study was conducted in 24 intensive care units in Anhui, China. MAIN OUTCOME MEASURES: Demographic and clinical data were collected, and rectal carbapenem-resistant Enterobacterales colonisation was detected by active screening. Multivariate logistic regression models were used to analyse factors associated with colonisation/infection with carbapenem-resistant Enterobacterales at admission and acquisition during the intensive care unit stay. RESULTS: There were 1133 intensive care unit patients included in this study. In total, 5.9% of patients with carbapenem-resistant Enterobacterales colonisation/infection at admission, and of which 56.7% were colonisations. Besides, 8.5% of patients acquired carbapenem-resistant Enterobacterales colonisation/infection during the intensive care stay, and of which 67.6% were colonisations. At admission, transfer from another hospital, admission to an intensive care unit within one year, colonisation/infection/epidemiological link with carbapenem-resistant Enterobacterales within one year, and exposure to any antibiotics within three months were risk factors for colonisation/infection with carbapenem-resistant Enterobacterales. During the intensive care stay, renal disease, an epidemiological link with carbapenem-resistant Enterobacterales, exposure to carbapenems and beta-lactams/beta-lactamase inhibitors, and intensive care stay of three weeks or longer were associated with acquisition. CONCLUSION: The prevalence of colonisation/infection with carbapenem-resistant Enterobacterales in intensive care units is of great concern and should be monitored systematically. Particularly for the 8.5% prevalence of carbapenem-resistant Enterobacterales acquisition during the intensive care stay needs enhanced infection prevention and control measures in these setting. Surveillance of colonisation/infection with carbapenem-resistant Enterobacterales at admission and during the patient's stay represents an early identification tool to prevent further transmission of carbapenem-resistant Enterobacterales. IMPLICATIONS FOR CLINICAL PRACTICE: Carbapenem-resistant Enterobacterales colonization screening at admission and during the patient's stay is an important tool to control carbapenem-resistant Enterobacterales spread in intensive care units.

A plasma-derived extracellular vesicle mRNA classifier for the detection of breast cancer.

BACKGROUND: According to the global cancer burden data released in 2020, breast cancer (BC) has become the most common cancer in the world. Similar to those of other cancers, the present methods used in clinic for diagnosing early BC are invasive, inaccurate, and insensitive. Hence, new non-invasive methods capable of early diagnosis are needed. METHODS: We applied next-generation sequencing and analyzed the messenger RNA (mRNA) profiles of plasma extracellular vesicles (EVs) derived from 14 BC patients and 6 patients with benign breast lesions. We used 3 regression models, namely support vector machine (SVM), linear discriminate analysis (LDA), and logistic regression (LR), to develop classifiers for use in making predictive BC diagnoses; and used 259 plasma samples, including those obtained from 144 patients with BC, 72 patients with benign breast lesions, and 43 healthy women, which were divided into training groups and validation groups to verify their performances as classifiers by quantitative reverse transcription polymerase chain reaction (RT-qPCR). The area under the curve (AUC) and accuracy, sensitivity, and specificity of the classifiers were cross-validated with the leave-1-out cross-validation (LOOCV) method. RESULTS: Among all combinations assessed with the 3 different regression models, an 8-mRNA combination, named EXOBmRNA, exhibited high performance [accuracy =71.9% and AUC =0.718, 95% confidence interval (CI): 0.652 to 0.784] in the training cohort after LOOCV was performed, showing the largest AUC in the SVM model. The mRNAs in EXOBmRNA were HLA-DRB1, HAVCR1, ENPEP, TIMP1, CD36, MARCKS, DAB2, and CXCL14. In the validation cohort, the AUC of EXOBmRNA was 0.737 (95% CI: 0.636 to 0.837). In addition, gene function and pathway analyses revealed that different levels of gene expression were associated with cancer. CONCLUSIONS: We developed a high-performing predictive classifiers including 8 mRNAs from plasma extracellular vesicles for diagnosing breast cancer.

Pharmacokinetic properties of S-adenosylmethionine after oral and intravenous administration of its tosylate disulfate salt: a multiple-dose, open-label, parallel-group study in healthy Chinese volunteers.

BACKGROUND: S-adenosylmethionine (SAMe) is an endogenous molecule that plays an important role in cellular metabolism. Despite being widely used as a dietary supplement with claimed benefits for numerous conditions, there is little information about the pharmacokinetic properties of exogenous SAMe. OBJECTIVES: One aim of this study was to characterize the pharmacokinetic properties of SAMe after administration of single and multiple doses of orally and intravenously administered SAMe tosylate disulfate (STD) in healthy male and female Chinese volunteers. Because men have higher erythrocyte levels of endogenous SAMe than do women, we also assessed the effects of sex on the disposition of SAMe. METHODS: A simple and sensitive assay for SAMe based on liquid chromatography-mass spectrometry using selected-ion monitoring of analyte and acyclovir as internal standard was developed and validated. The assay was used to study the pharmacokinetic properties of SAMe. STD was administered as single and multiple doses of enteric-coated tablets and IV infusion of STD to groups of healthy native Chinese volunteers. After an overnight fast, male and female Chinese volunteers were assigned to receive STD 1000 mg for 5 days, either in enteric-coated tablet formulation or as a 250-mL IV infusion. Blood samples were collected 24 hours after the first and last dose and used for determining plasma SAMe concentrations and pharmacokinetic parameters. For the oral formulation, SAMe concentrations were corrected for concentrations of endogenous SAMe. Pharmacokinetic parameters were calculated for men and women separately and for the total group of volunteers. Adverse events were monitored using a physician during blood collection and by spontaneous reporting. RESULTS: Twenty healthy volunteers were enrolled (oral formulation: 5 men, 5 women; mean [SD] age, 24.1 [4.7] years [range, 21-37 years]; mean [SD] weight, 59.9 [4.8] kg [range, 54-70 kg]; IV formulation: 5 men, 5 women; mean [SD] age, 22.6 [1.8] years [range, 21-27 years]; mean [SD] weight, 59.5 [5.4] kg [range, 53-67 kg]). None of the between-sex differences in SAMe pharmacokinetic properties were significant. The (mean [SD]) pharmacokinetic properties of singledose oral SAMe in men and women, respectively, were as follows: C(max), 2.37 (1.58) and 2.50 (1.83) micromol/L; T(max), 5.40 (1.14) and 5.20 (1.48) hours; AUC(0-24), 8.56 (5.16) and 10.3 (8.0) micromol/L/h; and t(1/2beta), 6.06 (1.80) and 6.28 (2.60) hours. Corresponding values with the single-dose IV formulation were: C(max), 127 (49) and 211 (94) micromol/L; T(max), 1.90 (0.22) and 1.60 (0.22) hours; AUC(0-24), 329 (84) and 480 (176) micromol/L/h; and t(1/2beta), 4.34 (0.57) and 3.83 (0.78) hours. The single-dose oral:IV ratios of AUC(0-24) in men and women, respectively, were 2.60% and 2.14% (degrees of fluctuation: 4.96 [1.77] and 9.49 [0.91]). The pharmacokinetic properties of multiple-dose oral and IV SAMe were not significantly different from those with single-dose administration. None of the volunteers reported any adverse events during the study. CONCLUSIONS: In this small study in healthy Chinese volunteers, there were no significant differences in the pharmacokinetic parameters of SAMe between men and women or between single- and multiple-dose administration of STD 1000 mg administered orally or intravenously. No evidence of accumulation of SAMe in plasma was found on multiple dosing. Both enteric-coated tablets and the IV infusion were well tolerated in these volunteers.

Evaluation of the biocompatibility of acellular porcine dermis.

The biocompatibility of an acellular porcine dermis was evaluated by in vitro methods. Endothelia cells (ECV-304) and fibroblasts (NIH-3T3) were seeded on the dermis and cultured for 1 week to assess the cell viability in the skin grafts. Results by morphological assessment and methylthiazolyl tetrazolium assay (MTT assay) indicated good biocompatibility of acellular porcine dermis, which allowed adhesion and proliferation of examined cell types. Flow chamber technique was used to evaluate the adhesive force between cells and biomaterials. There was no significant difference in cells retention ratio between control cells and experimental cells after sheared 24h. The determination of integrin alpha5 expression proved that the acellular porcine dermis did not influence the expression of integrin alpha5 in cells. The results suggested that the dermal equivalent made from pigskin is a promising material for burn treatment.

Steep pulsed electric fields modulate cell apoptosis through the change of intracellular calcium concentration.

A steep electric pulsed field with low intensity (150-250V/cm) and relative long time (10 min) was applied to adherent liver cancer cell line SMMC-7721 and the liver cell line HL-7702. Results showed that the electric field with intensity of 200 and 250V/cm could trigger cell apoptosis, whereas the SMMC-7721 cell was more sensitive to the electric stimulation than the HL-7702 cell. Laser Scanning Confocal Microscope (LSCM) was used to measuring the real-time change of cytosolic free Ca(2+) concentration. When cells were exposed electric pulses with 100V/cm intensity for 10 min, there was no significant change of intracellular calcium concentration. With the intensity increased to 200 and 250V/cm, intracellular calcium concentration decreased significantly. Results demonstrated the relationship between the apoptosis and change of intracellular calcium concentration. And the steep electric pulsed field can be used to the cancer therapy.

The MGF expression of osteoblasts in response to mechanical overload.

Cell proliferation and mRNA expression of insulin-like growth factor (IGF-I) and "mechanogrowth factor" (MGF) were studied in osteoblasts in response to overload. Static and cyclic-stretching were used to apply superphysiological strains to cells. Overload was found to increase cell growth. IGF-I and its splicing variant, MGF, were measured using reverse transcriptase-polymerase chain reaction method and were found to be regulated differentially by mechanical signals at the mRNA level. Cyclic-stretching had a more significant effect on cell proliferation and mRNA expression levels of IGF-I and MGF, while unstrained cells did not express MGF at the mRNA level. These results demonstrated that gene expression is regulated by mechanical stimulation. MGF expression in osteoblasts in response to strain may be related to an autocrine mechanism.

The stress reaction and its molecular events: splicing variants.

The growth of cells and tissues is regulated by stress. When body is injured, it manifests a large spectrum of metabolic, endocrine, and immune alterations, which is named stress reaction. Among them, the production of growth factors may play a critical role. For osteoblasts and myoblasts, IGF-I has been shown to be involved in the process of cells in response to overloads. There are two splicing forms, one is IGF-Ea, the other is the IGF-IEb in the rodents and corresponds to IGF-IEc in humans. The latter is markedly up-regulated in response to overloads. Therefore, it has been named mechanogrowth factor. The link between the mechanical stimulus and the gene expression represents a new and important area in cell science. Understanding the process of splicing in IGF-I helps one to investigate the mechanotransduction of cells in response to mechanical stimulation at molecular level.

The effect of step-wise increased stretching on rat calvarial osteoblast collagen production.

Mechanical forces regulate the function of bone cells. In this paper, the effects of cyclic stretching on osteoblasts derived from rat calvaria were studied at a magnitude occurring in physiological loaded bone tissue. A four-point bending apparatus was used to apply cyclic stretching on osteoblasts. Stretching at 500 microepsilon for 2-24 h resulted in an increase in matrix synthesis(P<0.01). In contrast, the cyclic stretching at 1000 and 1500 microepsilon for 2-24 h inhibited osteoblast collagen production (P<0.01). We also described our new loading method to increase strain magnitude step-by-step. The strain magnitude increased by 500 microepsilon increments from 500 to 1500 microepsilon every 2 or 12 h, respectively. Results showed that osteoblasts could absorb large amount of proline for collagen synthesis when stretched at 500 microepsilon. However, not all the absorbed proline was used to synthesize collagen. Some of it was stored in cells. When the suitable signal (500 microepsilon) was changed to an inhibiting signal (1000 microepsilon), cells responded to it accordingly and released proline to medium. These results demonstrate that the response of osteoblasts is dependent on the magnitude of the strain applied and cells can adjust their bio-chemical response to adapt to the changing environmental stimulation.