A dynamic prediction model for preeclampsia using the sFlt-1/PLGF ratio combined with multiple factors.

OBJECTIVE: Preeclampsia (PE) is a pregnancy-related multi-organ disease and a significant cause of incidence rate and mortality of pregnant women and newborns worldwide. Delivery remains the only available treatment for PE. This study aims to establish a dynamic prediction model for PE. METHODS: A total of 737 patients who visited our hospital from January 2021 to June 2022 were identified according to the inclusion and exclusion criteria, forming the primary dataset. Additionally, 176 singleton pregnant women who visited our hospital from July 2022 to November 2022 comprised the verification set. We investigated different gestational weeks of sFlt-1/PLGF (soluble FMS-like tyrosine kinase-1, placental growth factor) ratio combined with maternal characteristics and routine prenatal laboratory results in order to predict PE in each trimester. Multivariate logistic regression was used to establish the prediction model for PE at different gestational weeks. The discrimination, calibration, and clinical validity were utilized to evaluate predictive models as well as models in external validation queues. RESULTS: At 20-24 weeks, the obtained prediction model for PE yielded an area under the curve of 0.568 (95% confidence interval, 0.479-0.657). At 25-29 weeks, the obtained prediction model for PE yielded an area under the curve of 0.773 (95% confidence interval, 0.703-0.842)and 0.731 (95% confidence interval, 0.653-0.809) at 30-34 weeks. After adding maternal factors, uterine artery pulsation index(Ut-IP), and other laboratory indicators to the sFlt-1/PLGF ratio, the predicted performance of PE improved. It found that the AUC improved to 0.826(95% confidence interval, 0.748 ∼ 0.904) at 20-24 weeks, 0.879 (95% confidence interval, 0.823 ∼ 0.935) at 25-29 weeks, and 0.862(95% confidence interval, 0.799 ∼ 0.925) at 30-34 weeks.The calibration plot of the prediction model indicates good predictive accuracy between the predicted probability of PE and the observed probability. Furthermore, decision-curve analysis showed an excellent clinical application value of the models. CONCLUSION: Using the sFlt-1/PLGF ratio combined with multiple factors at 25-29 weeks can effectively predict PE, but the significance of re-examination in late pregnancy is not significant.

A Multiple-Target Simultaneous Detection Method for Immunosorbent Assay and Immunospot Assay.

Enzyme-linked immunosorbent assay (ELISA) is one of the most common methods in biological studies, and enzyme-linked immunospot (ELISpot) is a method to measure specific cell numbers by detecting protein secretion at a single-cell level. However, these two current methods can only detect one signal at one time and the sensitivity is not high enough to test low-concentration samples, which are major shortcomings in systematically analyzing the samples of interest. Herein, we demonstrated fluorescence-based oligo-linked immunosorbent assay (FOLISA) and fluorescence-based oligo-linked immunospot (FOLISPOT), which utilized DNA-barcoded antibodies to provide a highly multiplexed method with signal amplification. Signal amplification and simultaneous multiple-target detection were achieved by DNA complementary pairing and modular orthogonal DNA concatemers. By comparing FOLISA with traditional ELISA and comparing FOLISPOT with traditional ELISPOT, we found that the detection sensitivities of FOLISA and FOLISPOT are much higher than those of traditional ELISA and ELISPOT. The detection limit of ELISA is around 3 pg/mL, and the detection limit of FOLISA is below 0.06 pg/mL. FOLISPOT can detect more spots than ELISPOT and can detect targets that are undetectable for ELISPOT. Furthermore, FOLISA and FOLISPOT allowed sequential detection of multiple targets by using a single dye or multiple dyes in one round and sequential detection in multiple rounds. Thus, FOLISA and FOLISPOT enabled simultaneous detection of a large number of targets, significantly improved the detection sensitivity, and overcame the shortcomings of ELISA and ELISPOT. Overall, FOLISA and FOLISPOT presented effective and general platforms for rapid and multiplexed detection of antigens or antibodies with high sensitivity, either in laboratory tests or potentially in clinic tests.

One-Pot Synthesis of α-Ketoamides from α-Keto Acids and Amines Using Ynamides as Coupling Reagents.

A one-pot strategy for α-keto amide bond formation have been developed by using ynamides as coupling reagents under extremely mild reaction conditions. Diversely structural α-ketoamides were afforded in up to 98% yield for 36 examples. This reaction features advantages such as practical coupling procedure, wide functional group tolerance, and extremely mild conditions and has potential applications in synthetic and medicinal chemistry.

Prognostic factors of malignant peritoneal mesothelioma: a retrospective study of 52 female patients.

BACKGROUND: Prognosis in malignant peritoneal mesothelioma (MPM) remains poor, and the associated factors are unclear. Therefore, this study aimed to investigate the prognostic factors of MPM. METHODS: A total of 52 female MPM patients treated in 2012-2017 were retrospectively analyzed. Kaplan-Meier survival curves were generated for survival analysis by the log-rank test. The Cox regression model was used for univariate and multivariate analyses. RESULTS: Univariate analysis showed that median survival time (MST) was longer in the epithelioid type compared with the sarcomatoid type (12 months vs 5 months); cumulative survival rates at 12 months were 45.7% and 0%, respectively (P=0.005). MST was longer in patients with proliferating cell nuclear antigen (Ki67) ≤ 10% compared with those with Ki67 > 10% (15 months vs 11 months). Cumulative survival rates at 12 months were 60.0% and 28.1%, respectively (P=0.036). MSTs in patients administered peritoneal biopsy or adnexectomy + paclitaxel + platinum perfusion, peritoneal biopsy (or adnexectomy) + pemetrexed + platinum perfusion, cytoreductive surgery + paclitaxel + platinum perfusion, and cytoreductive surgery + pemetrexed + platinum perfusion were 6, 11, 12, and 24 months, respectively, with cumulative survival rates at 12 months of 0%, 35.7%, 45.5%, and 73.3%, respectively. Survival time after cytoreductive surgery combined with pemetrexed + platinum was the longest. In multivariate analysis, pathological type, T staging, and therapeutic regimen were independent prognostic factors of MPM (P < 0.05). CONCLUSIONS: Prognosis in MPM is associated with pathological subtype, clinical staging, cytoreductive surgery, and subsequent pemetrexed use. Radical cytoreductive surgery and postoperative use of pemetrexed prolong survival.

Association between TNF, IL1B, IL6, IL10 and IFNG polymorphisms and recurrent miscarriage: a case control study.

BACKGROUND: Approximately half of recurrent miscarriages have unexplained etiology. Recent evidences suggest that cytokines are important determinants in pregnancy maintenance and as such, cytokine gene polymorphisms, which can affect cytokine production and/or functionality, could play a role in the disorder. Thus, we aimed to investigate the association of selected cytokine gene polymorphisms with risk of recurrent miscarriage among Chinese. METHODS: TNF -238G > A, TNF -308G > A, IL1B -511 T > C, IL1B 3954C > T, IL6 -174G > C, IL6 -634C > G, IL10 -1082A > G and IFNG 874A > T polymorphisms were genotyped on 775 women with idiopathic recurrent miscarriage and 805 healthy parous control women. Logistic regression analysis was performed to determine the odds ratios (ORs) of the association between the polymorphisms and recurrent miscarriage risk. RESULTS: Among the eight polymorphisms studied, only the IL1B -511 T > C and IL6 -634C > G polymorphisms showed statistically significant associations with recurrent miscarriage risk. For the former, a significantly increased risk of recurrent miscarriage was observed for the mutant (CC) genotype (OR: 1.377; 95% CI: 1.039-1.824; P = 0.026). However, for the IL6 -634C > G polymorphism, a decreased recurrent miscarriage risk was observed for the heterozygous (CG) genotype (OR: 0.614; 95% CI: 0.493-0.765; P < 0.001) and the mutant (GG) genotype (OR: 0.414; 95% CI: 0.251-0.684; P = 0.001). CONCLUSIONS: The IL1B -511 T > C polymorphism may serve as important risk factor for recurrent miscarriage while the IL6 -634C > G polymorphism may protect against the risk of recurrent miscarriage.

Effects of metronidazole combined probiotics over metronidazole alone for the treatment of bacterial vaginosis: a meta-analysis of randomized clinical trials.

OBJECT: To evaluate the curative effect of metronidazole combined probiotics over metronidazole alone in the treatment of BV. METHODS: We are searching randomized controlled trials on major online databases including PubMed, Science Direct, and Cochrane Database between 1990 and 2015. The primary outcome measure was the cure rate of BV. Cochran's Chi-square test (Q test) was used to test for heterogeneity among trials, and the I 2 index. We used mixed-effects modeling for parameters of the summary hazard ratios (HRs), odds ratios (ORs), and their 95% confidence intervals (CIs). RESULTS: Analysis suggests the cure rate of BV [RR = 1.12, 95% CI (0.94-1.32), p = 0.20], and the I 2 index was 83%. The value of I 2 index decreased to 16% after removing the study of Anukam et al., and Amsel 1.04 (95% CI 0.96-1.13) (p = 0.35), Nugent 1.02 (95% CI 0.94-1.11), short-term 1.01 (95% CI 0.93-1.10) (p = 0.79), long-term 1.06 (95% CI 0.98-1.14) (p = 0.13), Europe 1.06 (95% CI 0.95-1.19) (p = 0.32), Non-Europe 0.99 (95% CI 0.94-1.05) (p = 0.83). When the two same groups data were combined, respectively, the RRs for all studies were the same as 1.03 (95% CI 0.96-1.09) (p = 0.42) showing that there is not statistically significant in relevant stratums. CONCLUSION: The result has showed an overall little significance for the efficacy of metronidazole combined probiotics over metronidazole alone for the treatment of BV. We need more further studies to provide enough evidence to confirm the benefits of probiotics in the treatment of BV.

[Progress in studies on the relationship between Dicer and ovarian tumor].

MiRNAs are short, noncoding RNAs that modulate gene expression at the posttranscriptional level and induce the degradation of the mRNA transcript or the inhibition of protein translation. Dicer is an endoribonuclease in the RNase III family that is essential for the production of miRNAs. The abnormal expression of Dicer is frequently found in the occurrence and development process of many kinds of tumors, which is closely related to the treatment and prognosis of tumor.

[Detection of somatic mutations in deteriorated cell of peritoneal mesothelioma by whole genome sequencing].

OBJECTIVE: To detect the somatic mutations in peritoneal mesothelioma with whole genome sequencing technique. METHODS: Surgically resected cancer and pericancerous tissue samples from one patient with peritoneal mesothelioma were obtained. The whole genome sequences of tumor tissue and pericancerous tissue were examined by the second generation sequencing technique and compared with reference sequences from human genome database. RESULTS: There were 639 717 single nucleotide variations (Single Nucleotide Variation SNV) found in both tumor and pericancerous tissue cells; while 20 302 SNVs were unique for tumor cells and 2 185 SNVs unique for pericancerous tissue, but still 223 SNVs found in cancer and pericancerous tissue were differed from those in human genome database. CONCLUSION: The preliminary results indicate that merely comparing the gene sequences of cancer and pericancerous tissue samples in an individual with the human genome reference sequence can not accurately locate all somatic mutations in pathological cells. For those individualized diseases caused by random somatic mutations, it is suggested to sequence the whole genome at birth or at least to reserve a DNA sample at early age for both research and clinical needs.

Validation of Self-Regulated Writing Strategies for Advanced EFL Learners in China: A Structural Equation Modeling Analysis.

This study aims to validate self-regulated writing strategies for advanced EFL learners through a structural equation modeling analysis. Two sets of advanced, university-level EFL learners in China were recruited on the basis of results from a nationwide standardized English test. Sample 1 consisted of 214 advanced learners and served mainly as a data source for exploratory factor analysis. Sample 2 consisted of 303 advanced learners; data from this group were used to conduct confirmatory factor analyses. The results confirmed the goodness of fit of the hierarchical, multidimensional structure of self-regulated writing strategies. This hierarchic model has the higher order of self-regulation and the second order of nine self-regulated writing strategies that belong to four dimensions. In terms of model comparisons, the indices of Model 1 (nine-factor correlated model of EFL writing strategies for SRL) and Model 2 (four-factor second-order model of EFL writing strategies for SRL) mark significant improvements in terms of fit over the indices of Model 3 (one-factor second-order model of EFL writing strategies for SRL). This means the four-factor model (cognition, metacognition, social behavior, and motivational regulation) offered a better explanation for advanced EFL learners than the model treating self-regulated writing strategies as a single convergent factor. These findings, in some ways, differ from the results of earlier research on EFL learners' self-regulated writing strategies, and the findings of this study have certain implications for L2 writing teaching and learning.

Effects of Maleic Anhydride-Grafted Polyethylene on the Properties of Artificial Marble Waste Powder/Linear Low-Density Polyethylene Composites with Ultra-High Filling Content.

The need to reach carbon neutrality as soon as possible has made the use of recycled materials widespread. However, the treatment of artificial marble waste powder (AMWP) containing unsaturated polyester is a very challenging task. This task can be accomplished by converting AMWP into new plastic composites. Such conversion is a cost-effective and eco-friendly way to recycle industrial waste. However, the lack of mechanical strength in composites and the low filling content of AMWP have been major obstacles to its practical application in structural and technical buildings. In this study, a composite of AMWP/linear low-density polyethylene (LLDPE) filled with a 70 wt% AMWP content was fabricated using maleic anhydride-grafted polyethylene as a compatibilizer (MAPE). The mechanical strength of the prepared composites is excellent (tensile strength ~18.45 MPa, impact strength ~51.6 kJ/m2), making them appropriate as useful building materials. Additionally, laser particle size analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and thermogravimetric analysis were used to examine the effects of maleic anhydride-grafted polyethylene on the mechanical properties of AMWP/LLDPE composites and its mechanism of action. Overall, this study offers a practical method for the low-cost recycling of industrial waste into high-performance composites.

Litter inputs exert greater influence over soil respiration and its temperature sensitivity than roots in a coniferous forest in north-south transition zone.

The changes in carbon inputs of litter and roots to forest soils caused by climate change will result in a serious cascade effect on soil respiration and its temperature sensitivity (Q10). To differentiate and quantify the effects of surface litter and living roots on soil respiration and Q10, and further explore the role of abiotic factors and microbial properties on soil respiration and Q10, a short-term (two years) detritus input and removal treatment experiment was conducted in a coniferous forest of central China. Soil temperature, soil moisture, C/N, microbial biomass and community composition were analyzed to explore the drive mechanisms of soil respiration and Q10 in response to carbon inputs. The results showed that litter addition increased soil respiration by 22 %, while litter or roots removal did not affect soil respiration, which might be ascribed to the "priming effects" mediated by fresh plant litter. We also found that litter addition increased Q10, while litter removal decreased Q10. Litter addition significantly enhanced the microbial biomass for any single functional group and altered soil microbial community composition. Structural equation model further proved that microbial biomass and community composition exerted stronger impacts on Q10 than do soil abiotic factors. Soil moisture, microbial biomass and community structure were main factors in predicting soil respiration. The study highlights the important role of litter inputs compared with living roots in carbon cycling in short-term and deepens our understanding on the complex relationships among soil respiration, soil micro-environment and microbial community composition.

[Comprehensive analysis of therapeutic methods and effect on cesarean scar pregnancy].

OBJECTIVE: To evaluate the efficacies and medic economic efficiency of therapeutic method for cesarean scar pregnancy (CSP). METHODS: The pertinent literatures on the treatment of CSP were collected and screened by retrieving some Chinese and English databases, such as PubMed, VIP and Wanfang Data. The weighting means and polled standard deviations of operative duration, operative hemorrhage volume, hysterectomy rate, length of stay, medical fees and the time of serum level of beta-human chorionic gonadotropin (ß-HCG) returning to normal were reckoned. RESULTS: Among different therapeutic methods of CSP, curettage duration was shortest in the patients with methotrexate (MTX) injection; operative hemorrhage volume, hysterectomy rate and length of stay were smallest in those with uterine artery embolization; medical fees was least in those with local MTX injection; the time of serum ß-HCG level returning to normal was shortest in those with hysteroscopic and/or laparoscopic operation after MTX injection or uterine artery embolization. CONCLUSION: Curettage after uterine artery embolization offers multiple advantages over therapeutic methods in the treatment of CSP.

[Diagnostic and therapeutic analyses for peritoneal malignant mesothelioma: a report of 26 women].

OBJECTIVE: To investigate the etiology, clinicopathologic features and prognosis of peritoneal malignant mesothelioma (PMM). METHODS: The diagnostic and therapeutic data for PMM from March 2000 to December 2010 were retrospectively analyzed for 26 women. They had an age range of 41 - 78 years old. Among them, 21 patients (81%) had a history of exposure to asbestos. Their major symptoms were abdominal distension, abdominal pain, ascites and abdominopelvic mass. Some had cachexia. Intestinal obstruction occurred in all cases during a late stage. RESULTS: Among them, the tumor marker of CA125 increased markedly in serum and ascitic samples. The positive rate of ascitic cytology was 31%. Type B ultrasound and CT (computed tomography) examinations showed ascites, peritoneal thickening and abdominopelvic mass and pie-shaped omentum. Their general pathological classifications were as follows: diffuse type (n = 23), localized type (n = 3), epithelial (n = 14), sarcoma (n = 3) and mixed type (n = 9). Cytoreductive surgery was performed in 16 cases. Ten patients underwent only laparoscopy while 23 patients received chemotherapy. The comparison of life span was not statistically significant between cytoreductive surgery and laparoscopy (P > 0.05); the difference of life span between ≤ 6 courses of chemotherapy and < 6 courses was not statistically significant (P > 0.05). CONCLUSION: The history of exposure to asbestos is a risk factor for PMM. PMM with no specific clinical features should be combined with laboratory and imaging studies to make a timely clinical diagnosis. Final diagnosis should be based upon histopathological and immunohistochemical examinations. Surgery and chemotherapy do not prolong the life span of patients. And the patients have a very poor prognosis.

Metal-free cascade synthesis of unsymmetrical 2-aminopyrimidines from imidazolate enaminones.

A convenient metal-free synthesis of unsymmetrical 2-aminopyrimidines from imidazolate enaminones has been developed. In this procedure, various structural 2-aminopyrimidines, as well as 4,5-dihydroisoxazol-5-ols and pyrazoles were synthesized in moderate to excellent yields. A plausible mechanism was also proposed for the cascade reaction. This method represents an effective strategy towards the synthesis of unsymmetrical 2-aminopyrimidines.

Immunotherapy and Prevention of Cancer by Nanovaccines Loaded with Whole-Cell Components of Tumor Tissues or Cells.

Tumor tissues/cells are the best sources of antigens to prepare cancer vaccines. However, due to the difficulty of solubilization and delivery of water-insoluble antigens in tumor tissues/cells, including water-insoluble antigens into cancer vaccines and delivering such vaccines efficiently to antigen-presenting cells (APCs) remain challenging. To solve these problems, herein, water-insoluble components of tumor tissues/cells are solubilized by 8 m urea and thus whole components of micrometer-sized tumor cells are reasssembled into nanosized nanovaccines. To induce maximized immunization efficacy, various antigens are loaded both inside and on the surface of nanovaccines. By encapsulating both water-insoluble and water-soluble components of tumor tissues/cells into nanovaccines, the nanovaccines are efficiently phagocytosed by APCs and showed better therapeutic efficacy than the nanovaccine loaded with only water-soluble components in melanoma and breast cancer. Anti-PD-1 antibody and metformin can improve the efficacy of nanovaccines. In addition, the nanovaccines can prevent lung cancer (100%) and melanoma (70%) efficiently in mice. T cell analysis and tumor microenvironment analysis indicate that tumor-specific T cells are induced by nanovaccines and both adaptive and innate immune responses against cancer cells are activated by nanovaccines. Overall, this study demonstrates a universal method to make tumor-cell-based nanovaccines for cancer immunotherapy and prevention.

[Diagnosis and treatment of cesarean scar pregnancy].

OBJECTIVE: To investigate the suitable measures of diagnosis and treatment of cesarean scar pregnancy (CSP). METHODS: From May 2003 to February 2010, 52 cases were diagnosed as CSP on the basis of the history of cesarean section and the manifestations of pregnancy by transvaginal ultrasound and magnetic resonance imaging (MRI) examination. According to the blood level of ß-HCG, 32 patients underwent uterine artery methotrexate perfusion and uterine artery embolization (UAE), 20 cases received a protocol of methotrexate and leucovorin (CF) while UAE or Foley catheter balloon hemostasis was performed for massive vaginal bleeding cases. When ß-HCG decreased 80% - 90% and mass blood flow reduced or disappeared, focal resection was administered. RESULTS: Forty-six cases were diagnosed by transvaginal ultrasound and 6 cases by MRI. On admission, 11 patients with severe vaginal bleeding underwent UAE or Foley catheter hemostasis. Forty patients undergoing curettage had no uterine perforation or rupture with hysteroscopic guidance and laparoscopic monitoring if necessary. Among them, 39 (97.5%) cases were successful. Six cases were directly treated by laparotomy or laparoscopic focal resection and uterine repair. And 6 cases underwent conservative treatment without focal resection. 52 patients were cured successfully without any case of hysterectomy. CONCLUSION: Transvaginal ultrasound is the preferred diagnostic method of CSP while MRI is an auxiliary method for diagnosis. The treatment of CSP should be based on blood ß-HCG levels and lesion location, size, muscle thickness of surface, the condition of blood supply and vaginal bleeding. Different measures may be selected to kill embryos, stop hemorrhage and resect lesions.

The relationship between cervical precancerous lesion galectin-3 and p27 protein expression and clinical prognosis.

The relationship between galectin-3 and p27kip1 protein expression levels in cervical precancerous lesions and clinical prognosis were studied. A total of 74 patients with cervical intraepithelial neoplasia [(CIN), 20 cases classified as stage I, 24 cases as stage II and 30 cases as stage III] were enrolled in this study. Tissue galectin-3, p27kip1, vascular endothelial growth factor (VEGF)-2 and cyclin D protein levels were detected via immunohistochemical staining and reverse transcription polymerase chain reaction (PCR). Follow-up median duration was 13.5 months and recurrence rate was determined. Galectin-3, VEGF-2, and cyclin D expression was elevated in patients with higher stage CIN, whereas p27kip1 showed the opposite trend (p<0.05). During follow-up, there were 3 cases (15.0%) of recurrence in the CIN-I group, 5 cases (20.8%) in the CIN-II group and 9 cases (30.0%) in CIN-III the group. No significant difference in recurrence rate was noted among the groups (p>0.05). The upregulation of galectin-3 and downregulation of p27kip1 in CIN tissues may be related to tumor progression. This phenomenon will require further verification.

Joint angle estimation with accelerometers for dynamic postural analysis.

This paper presents a new accelerometer based method for estimating the posture of a subject standing on a dynamic perturbation platform. The induced perturbation is used to study the control mechanisms as well as the balance requirements that regulate the upright standing. These perturbations are translated into different intensity levels of speed and acceleration along longitudinal and lateral directions of motion. In our method, the human posture is modeled by a tridimensional, three-segment inverted pendulum which simultaneously takes into account both the anterior-posterior and medio-lateral strategies of hip and ankle. Four tri-axial accelerometers are used her, one accelerometer is placed on the platform, and the other three are attached to a human subject. Based on the results, the joint angle estimated compare closely to measurements from magnetic encoders placed on an articulated arm joint. The results were also comparable to those found when using a high-end optical motion capture system coupled with advanced biomechanical simulation software. This paper presents the comparisons of our accelerometer-based method with encoder and optical marker based method of the estimated joint angles under different dynamics perturbations.

Design of multiple axis robotic platform for postural stability analysis.

This paper presents the design and implementation of IsiMove, a new dynamic posturography platform. It allows the evaluation of the static and dynamic balance of a human placed on a force plate. IsiMove is a robotic platform open kinematic with four degrees of freedom: anteroposterior tilt, mediolateral tilt, vertical rotation, and horizontal translation. It is capable of measuring the displacement of the center of pressure over time, with a resolution of 0.1 mm for each foot and support a human of about 120 kg. IsiMove can generate various types of balance perturbations based on parameters such as direction, amplitude, frequency and shape. In this paper, we will give a description of the mechanisms that constitute our platform. First, the technical specifications of the hardware and software architecture will be presented. Then, we will provide details related to extensive experimental evaluations of the platform in both static and dynamic condition as well as result of postural stability analysis with healthy subjects and stroke patients.

Bench test evaluation of adaptive servoventilation devices for sleep apnea treatment.

RATIONALE: Adaptive servoventilation devices are marketed to overcome sleep disordered breathing with apneas and hypopneas of both central and obstructive mechanisms often experienced by patients with chronic heart failure. The clinical efficacy of these devices is still questioned. STUDY OBJECTIVES: This study challenged the detection and treatment capabilities of the three commercially available adaptive servoventilation devices in response to sleep disordered breathing events reproduced on an innovative bench test. METHODS: The bench test consisted of a computer-controlled piston and a Starling resistor. The three devices were subjected to a flow sequence composed of central and obstructive apneas and hypopneas including Cheyne-Stokes respiration derived from a patient. The responses of the devices were separately evaluated with the maximum and the clinical settings (titrated expiratory positive airway pressure), and the detected events were compared to the bench-scored values. RESULTS: The three devices responded similarly to central events, by increasing pressure support to raise airflow. All central apneas were eliminated, whereas hypopneas remained. The three devices responded differently to the obstructive events with the maximum settings. These obstructive events could be normalized with clinical settings. The residual events of all the devices were scored lower than bench test values with the maximum settings, but were in agreement with the clinical settings. However, their mechanisms were misclassified. CONCLUSION: The tested devices reacted as expected to the disordered breathing events, but not sufficiently to normalize the breathing flow. The device-scored results should be used with caution to judge efficacy, as their validity depends upon the initial settings.