Lactic acid is the main substance produced by Lactobacillus and plays an important role in maintaining a healthy vaginal microecology. Recent studies indicates that both L- and D-chiral isomers of lactic acid can be protonated and destroy the cell membranes of pathogens, thereby inhibiting bacterial vagi-nosis- and aerobic vaginitis-related pathogens. Lactic acid also can inhibit the pathogens of sexually transmit-ted diseases such as Chlamydia trachomatis and human immunodeficiency virus. Moreover, lactic acid acts as an immunomodulator to inhibit the inflammatory responses caused by pathogenic microorganisms and as an epigenetic regulator regulating gene expression in vaginal epithelial cells. In this paper, we reviewed the pro-gress in lactic acid-mediated maintenance of a healthy vaginal microbiology in recent years for providing ref-erence for further research.

Objective To analyze the value of vaginal microecological detection in evaluating therapeutic effect of simple vulvovaginal candidiasis(VVC), and explore microecological factors which can affect the cure rate of simple VVC.Methods 75 patients with simple VVC in Tianjin Medical University General Hospital from January 2016 to June 2017 were enrolled.Vaginal secretion was collected and applied for vaginal microecological detection.The patients were treated with clotrimazole based monotherapy later. The relationship between vaginal microecological characters and therapeutic effects was analyzed.Results PH values,leukocyte counts,flora density,flora diversity,small bacilli and cocci counts had no influence on therapeutic effects(P>0.05).The cure rate of patients with lactobacillary gradesⅠ-Ⅱa was higher than that with lactobacillary gradesⅡb-Ⅲ(83.33% vs 53.33%,P=0.033), while lower with lactobacilli≤22.8/hpf than that with lactobacilli >22.8/hpf(59.26% vs 87.50%,P=0.007), which indicate that lactobacilli counts was the main factor that affects therapeutic effects.Conclusions Vaginal microecological detection plays an important role in predicting the therapeutic effect of simple VVC.For the patients with lower lactobacillus counts,the follow-up after treatment should be strengthened.(Chin J Lab Med,2018, 41:292-295)

The mucosal immune system is the first line of defense against pathogens such as bacteria and viruses invading the bodies. The female reproductive tract mucosal immune system not only resists the invasion of pathogens through innate and adaptive immunity, but also contribute to successfully fertilization and pregnancy, thus maintaining the health of women′s reproductive system. The innate immunity of female genital tract involves the mechanical barrier of the mucosal epithelium, microbial barrier of commensal bacteria, immunological barrier of immune cells and their receptors, and adaptive immunity including B cell-mediated humoral immunity and T cell-mediated cellular immunity. Female genital mucosal immunity is not only involved in local inflammation, but may also have anti-tumor effects. Moreover, the female genital tract mucosal immune is also regulated by sex hormone to maintain a homeostasis of local microenvironment. Herein, this paper summarized recent progress in female genital mucosal immunity.

Objective Airway resistance(R)and lung compliance(C)under non-invasive positive pressure ventilation(NPPV)conditions were measured using a brief pressure release at the end of expiration,and the measurement accuracy was also evaluated.Methods An NPPV respirator was developed by programming a method for calculating R and C.An experimental platform based on the active servo lung ASL5000 was designed.By simulating a healthy adult(R=5 cmH2 O and C=50 mL/cmH2 O,1 cmH2 O=0.098 kPa),an adult patient with acute respiratory distress syndrome(R=10 cmH2 O and C=30 mL/cmH2 O),and an adult patient with chronic obstructive pulmonary disease(R=20 cmH2 O and C=50 mL/cmH2 O),a series of experiments for calculating the R and C were conducted.Results The maximum relative error of R was-12.67%,which occurred in calculating the R of an average adult.The maximum relative error of C was 17.37%,which occurred when calculating the C values of patients with acute respiratory distress syndrome.Each group of data was analyzed using a paired t-test,which showed statistically significant differences(P>0.05).Conclusions The calculation method for R and C at the end of expiration during NPPV is feasible,and its realization and application will be beneficial for achieving precise and personalized respiratory ventilation.

Objective Under noninvasive positive pressure ventilation, in view of inconvenient operations in human airway, and avoiding the interference of spontaneous breathing and the necessary leakage flow, the method for dynamic online monitoring of the respiratory resistance (R) and compliance (C) was studied.Methods At the end of expiration, when the exhaled flow was 0, relative to the expiration positive airway pressure (EPAP), a step-dropped pressure was produced with the amplitude Δp and hold time Δt. Under this dropped pressure, a short-time discharged flow was generated from the lung, and the discharged flow was applied to calculate the R and C. In addition, a respiratory model was developed in MATLAB to simulate the breaths of normal adult, acute respiratory distress syndrome (ARDS) patient and chronic obstructive pulmonary disease (COPD) patient. A serial of simulation experiments were carried out for obtaining data and verification.Results The calculated R and C from simulation for normal adult, ARDS patient, COPD patient, deviated from the actual value by 1.60% and -1.60%, 1.21% and -1.19%, -12.53% and 14.32%, respectively.Conclusions The proposed algorithm is practicable and feasible for calculating the R and C. The simulation results are beneficial for studying and realizing the intelligent ventilation and proportional assist ventilation in respirator.

Objective T o analyze the influence of high flow nasal cannula (HFNC) on trespiratory mechanical parameters of the patient with acute respiratory distress syndrome (ARDS) based on ventilation experiment, and investigate the therapeutic and side effects of the HFNC. Methods The HFNC ventilation system model based on MATLAB and the physical experiment platform based on active simulated lung ASL5000 were developed to simulate the respiratory movement of ARDS patients with different lung compliance, and a series of the HFNC ventilation experiments were carried out. Both experimental results in MATLAB and physical platform were compared and analyzed. Results The results from the Matlab model-based simulation experiment and physical platform based-physical experiment uniformly showed that increasing the output flow of HFNC would decrease the relevant respiratory mechanical parameters of respiratory flow and tidal volume, but increase the intrapulmonary pressure and the functional residual capacity (FRC). Under the condition of small flow, the output flow from HFNC might be smaller than the inspiratory flow required by the patient, and an inspiratory compensation flow was necessary to make up for the inspiratory flow. Conclusions The necessary reliable compensation flow in inspiration will promote the security of HFNC. Understanding the changes in respiratory mechanical parameters of ARDS patient will be beneficial to pre-evaluate the HFNC, improve the ventilation effect and reduce the ventilation risks.

Objective To compare biomechanical properties between the anatomical clavicle plate and the reconstructed clavicle plate, and investigate the influence of pre-bending or repeated bending process on biomechanical properties of the reconstructed clavicle plate, so as to provide biomechanical evidence for treating midshaft clavicle fracture in clinic. Methods The reconstructed clavicle plate was bent by 1, 2, 3, 5 times respectively based on shape of the anatomical clavicle plate. The biomechanical differences in anatomical plate group, reconstructed plate group and pre-bending plate group were compared by static compression test. Results The fixation stiffness and strength of the anatomical plate were better than those of the reconstructed plate. There was no significant difference in stiffness and strength between the anatomical plate group and one-time bending group. Pre-bending had a great effect on mechanical properties of the clavicle plate, and stiffness and strength of the clavicle plate were obviously improved after one-time bending. The mechanical properties of the clavicle plate were obviously reduced by bending of the clavicle plate after one-time bending. Conclusions The stiffness and strength of the anatomical plate and one-time bending plate are higher than those of the normal reconstructed plate. It is recommended that surgeons should perform bending appropriately according to the patient’s clavicle anatomy when using the reconstructed clavicle plate for fracture fixation, and minimize the number of repeated bending to maintain stiffness and strength of the clavicle plate.

Without artificial airway though oral, nasal or airway incision, the bi-level positive airway pressure (Bi-PAP) has been widely employed for respiratory patients. In an effort to investigate the therapeutic effects and measures for the respiratory patients under the noninvasive Bi-PAP ventilation, a therapy system model was designed for virtual ventilation experiments. In this system model, it includes a sub-model of noninvasive Bi-PAP respirator, a sub-model of respiratory patient, and a sub-model of the breath circuit and mask. And based on the Matlab Simulink, a simulation platform for the noninvasive Bi-PAP therapy system was developed to conduct the virtual experiments in simulated respiratory patient with no spontaneous breathing (NSB), chronic obstructive pulmonary disease (COPD) and acute respiratory distress syndrome (ARDS). The simulated outputs such as the respiratory flows, pressures, volumes, etc, were collected and compared to the outputs which were obtained in the physical experiments with the active servo lung. By statistically analyzed with SPSS, the results demonstrated that there was no significant difference ( P > 0.1) and was in high similarity ( R > 0.7) between the data collected in simulations and physical experiments. The therapy system model of noninvasive Bi-PAP is probably applied for simulating the practical clinical experiment, and maybe conveniently applied to study the technology of noninvasive Bi-PAP for clinicians.
Humans ; Respiration, Artificial/methods* ; Positive-Pressure Respiration/methods* ; Respiration ; Ventilators, Mechanical ; Lung