Time to positivity(TTP) is a new parameter in blood culture field.The article shows us the concepts of TTP,differential time to positivity (DTTP),and introduces their relation with bloodstream infection (BSI),catheter-related bloodstream infection (CRBSI).Besides,it stresses TTP' s clinical application,including determining the severity of disease;identifying the isolates whether pollution or not; identification of isolate strains ; detection of the drug resistance of isolates ; evaluating the effect of antibiotic ; helping to adjust the therapeutic drug; diagnosing or excluding CRBSI by means of DTTP;deciding whether the catheter is the source of infection in patients with candidemia; understanding the epidemiological distribution of strain.At the same time,the article also describes the shortcomings and domestic current status.

Objective To provide a comprehensive reference index for different mouse models of herpes simplex virus 1 (HSV-1) infection by investigating the related clinical manifestations, pathological features and characteristics of viral distribution in tissues and organs of BALB/c mice infected with different HSV-1 strains by using different strategies.Methods Acute infection models were established by challenging BALB/c mice at age three or six weeks with HSV-1 17+ and McKrae strains via intranasal and corneal administrations.Correspondingly, chronic infection models were established with BALB/c mice through subcutaneous and foot pad injections.Results Although all experimental mice showed trichiasis and roachback, there were differences in weight and fatality rate among different groups.Results of the quantitative PCR detection indicated that the proliferation of HSV-1 in the nervous tissues (brain, spinal cord, trigeminal ganglion) varied among different groups.The pathological examination indicated that in the acute infection groups, significant pathological changes only occurred in the brain tissues, while in the chronic infection groups, pathological injuries only occurred in the trigeminal ganglia.Although a key index latency-associated transcript (LAT) was not detected in the trigeminal nerve tissues of mice in the chronic infection groups, co-culturing the tissues with Vero cells resulted in infectious lesions in the cells.Conclusion This study indicates that there are significant differences in weight and fatality rate among different BALB/c mouse models of HSV-1 infection.Varied replication dynamics of HSV-1 were observed in different tissues or organs of the BALB/c mice in different groups.Therefore, different indexes should be adopted to evaluate different HSV-1 infection models.

Presepsin(sCD14-ST), is an soluble leukocyte differentiation antigen 14 subtype. It is a glycoprotein fragment and a marker of acute phase reaction. For diagnosis of adult sepsis, bacteremia and bacterial DNAaemia, the area under of ROC is 0.88,0.78 and 0.79, respectively. The levels of Presepsin increase earlier than procalcitonin, and have better clinical value for early diagnosis of sepsis. It is significantly correlated with disease severity and can be used to predict prognosis. One study mentioned that in the absence of organ dysfunction, the value was 235.0 (172.0-340.3) pg/ml, and for one, two, three or more organ dysfunction, were 403.5 (275.8-587.3) pg / ml, 844.5 (559.8-1259.5) pg / ml, 1412.5 (893.0-2675.8) pg/ml (P<0.01), respectively. Another study mentioned that Presepsin is an independent risk factor for 30-day death of sepsis, and it is effective to evaluate poor prognosis with a threshold of >927.5 pg/ml. Presepsin also has clinical value for neonatal and child sepsis. The Greece meta-analysis showed that the AUC for neonatal sepsis diagnosis was 0.9751, which was higher and more sensitive than that of CRP and procalcitonin. Turkish study on children showed a significant increase in sCD14-ST in sepsis patients compared with healthy controls. Its AUC was 0.98, the best threshold was 990 pg/ml. The reference range of this value was been studied, showing that 75％ and 95％ percentiles of full-term infants are 791 and 1178 pg/ml. Adults do not exceed 200 pg/ml of all age groups. It is affected by renal function. Prospective trials are expected to further clarify its diagnostic value, more therapeutic research to elaborate its therapeutic value, and corresponding clinical practice guideline.

Objective:To investigate the risk factors of diabetes mellitus complicated by pulmonary tuberculosis.Methods:The clinical data of 83 patients with diabetes mellitus complicated by pulmonary tuberculosis who received treatment in Taiyuan Fourth People's Hospital from March 2020 to March 2022 were collected. These patients were divided into sensitive group ( n = 45) and resistant group ( n = 38 ) according to the results of drug sensitivity test. Univariate and multivariate non-conditional logistic regression was performed to analyze the influential factors of drug resistance. Results:Univariate logistic regression results revealed that there were significant differences in blood CD4 +T lymphocyte count ( χ2 = 11.73, P = 0.001) and diabetic complications ( χ2 = 4.94, P = 0.026). Multivariate non-conditional logistic regression analysis was performed taking whether blood CD4 +T lymphocyte count was lower than the average level and whether patients with diabetes mellitus had complications as independent variables, and taking whether drug resistance was a dependent variable. The results showed that the OR (95% CI) value of the decreased blood CD4 +T lymphocyte count was 4.909 (1.926-12.514). It is a risk factor for drug resistance of diabetes mellitus complicated by pulmonary tuberculosis. Conclusion:The decrease of blood CD4 +T lymphocyte count is a risk factor of drug resistance in diabetes mellitus complicated by pulmonary tuberculosis, and it should be intervened early in the clinic.