Missing data represent a general problem in many scientific fields, especially in medical survival analysis. Dealing with censored data, interpolation method is one of important methods. However, most of the interpolation methods replace the censored data with the exact data, which will distort the real distribution of the censored data and reduce the probability of the real data falling into the interpolation data. In order to solve this problem, we in this paper propose a nonparametric method of estimating the survival function of right-censored and interval-censored data and compare its performance to SC (self-consistent) algorithm. Comparing to the average interpolation and the nearest neighbor interpolation method, the proposed method in this paper replaces the right-censored data with the interval-censored data, and greatly improves the probability of the real data falling into imputation interval. Then it bases on the empirical distribution theory to estimate the survival function of right-censored and interval-censored data. The results of numerical examples and a real breast cancer data set demonstrated that the proposed method had higher accuracy and better robustness for the different proportion of the censored data. This paper provides a good method to compare the clinical treatments performance with estimation of the survival data of the patients. This pro vides some help to the medical survival data analysis.
Algorithms ; Breast Neoplasms ; epidemiology ; Female ; Humans ; Probability ; Statistics, Nonparametric ; Survival Analysis

To study the effects of major components of Maijunan tablets, puerarin (Pue) and rhynchophylline (Rhy) on the transport of hydrochlorothiazide (Hct) Caco-2 cell monolayer model, the transport parameters of Hct, such as apparent permeability coefficient (P(app) (B --> A) and P(app) (A --> B)) and the ratio of P(app) (B --> A) versus P(app) (A --> B), were studied and compared when Hct was used solely and co-used with Pue and/or Rhy. The effects of drug concentrations, conveying times, P-glyprotein (P-gp) inhibitor verapamil and conveying Liq pH values on the transport of Hct in the above conditions were also investigated. The results indicated that the absorption of Hct in Caco-2 cell monolayer model could be a carrier-mediated active transport, along with the excretion action mediated by P-gp. Pue can decrease the excretion action of Hct mediated by P-gp, and Rhy had no significant effect on the transport of Hct. The co-use of Hct, Pue and Rhy enhanced the absorption of Hct. Meanwhile, conveying Liq pH value had significant influence on the transport of Hct. The absorption of Hct at pH 6.0 was higher than that at pH 7.4.

The experiment aimed to study the toxic effect of oral ricin on gastrointestinal tract and immune organs of mice with the dose of 1/5 LD50.In early days of intoxication,there was an obviously decrease in daffy weight and relative weight of thymus and spleen,fllowing the excretion of toxin,they had a trend of recovering to the normal state.Also,results of pathological section,scanning electron microscope and transmission electron microscope showed that ricin would induce a series of pathological reaction in intestines,meanwhile,the splenocytes displayed significant symptom of apoptosis and necrosis.

Objective:To investigate the effect of Masquelet technique combined with platelet-rich plasma (PRP) on repair of massive tibial defects.Methods:A prospective randomized controlled single blind trial was conducted in the 21 patients who had been admitted to Department of Repair and Reconstruction Surgery, Foshan Hospital of Chinese Medicine for massive tibial defects from June 2016 to June 2018.The length of bone defects ranged from 6.0 to 22.5 cm (mean, 10.8 cm)in length.They were 14 males and 7 females, aged from 29 to 60 years(mean, 42.1 years).The patients were divided into 2 groups by an en-crypting envelope with a random digital table.In the experimental group of 11 cases, the bone defects were repaired with Masquelet technique combined with PRP; in the control group of 10 cases, the bone defects were reconstructed with only Masquelet technique.The 2 groups were compared in terms of operation time, hospital stay, wound healing, weight-bearing time, bony union time, clinical union time, complications and John-er-Wruhs scores at the second stage.Results:The 2 groups were comparable due to insignificant differ-ences between them in the preoperative general data ( P>0.05).All patients were followed up for 12 to 24 months (mean, 14.9 months).There were no significant differences in operation time, hospital stay, wound healing, weight-bearing time, Johner-Wruhs scores or rate of complications at the second stage between the 2 groups ( P>0.05).The bony union time (4.5 months ± 1.2 months) and clinical union time (4.1 months ± 0.9 months) in the experimental group were significantly shorter than those (5.7 months ± 1.5 months and 5.4 months ± 1.1 months) in the control group ( P<0.05).No such postoperative complications as infection, loosening of internal fixator, bone resorption or nonunion were found in the experimental group.One case of wound infection occurred in the control group but responded to dressing change. Conclusion:Masquelet technique combined with PRP is a safe and effective reparative treatment for massive tibial defects and can speed up bone healing.

Objective:Microvascular clip plays important role in microsurgery. Therefore, the development of microvascular clips and research in clamp-related vascular injuries becomes a major topic. Based on clamp-related microvascular injuries, the study investigated in 4 aspects: injury assessment, vascular characteristics and blood vessel injury, vessel repair, and development of microvascular clamp. A prospects of the current researches is also given.

Objective:To explore the method and clinical efficacy of Flow-through latissimus dorsi musculocutaneous flap to repair children’s limb wounds.Methods:From January, 2017 to September, 2019, the Flow-through latissimus dorsi myocutaneous flap was used to repair the limb wounds in 9 children, which were 3 cases of upper extremity wounds and 6 cases of lower extremity wounds. The patients were 5-12 years old, with an average age of 9.4 years. The wound debridement was performed in the first stage, and the wound was covered with VSD. The second operation was performed 5-8 days later. Flow-through free latissimus dorsi muscle flap was used to repair the wound, and 6 patients combined with skin grafting. During the operation, both ends of the recipient area artery were trimmed into a downward slant. The proximal end of the recipient area blood vessel was coincided with the subscapular artery, the distal end was coincided with the circumflex scapular artery, and the thoracodorsal vein and the recipient area vein were coincided. One patient had 2 thoracodorsal veins, and 8 patients had 1 thoracodorsal vein. After the operation, the patients were given anti-infection, anticoagulation and antispasmodic treatment. And regular follow-up.Results:In this group, 8 flaps survived completely, and 1 had partial epidermal necrosis, which healed under the scab. Skin grafting survives well. Nine patients were followed-up for 3 to 28 months, 7 of which were followed-up in the outpatient clinic, and 2 by WeChat. CDU showed smooth blood flow in all patients 1 month after operation, in addition of 3 after 1 year. The flap had good blood flow and soft texture. Flap plastic surgery was performed in 3 cases.Conclusion:Using Flow-through latissimus dorsi musculocutaneous flap to repair the wounds of the children’s limbs, the flap survived well after the operation, and the blood circulation of the main vessel in the affected area was smooth, which had no obvious effect on the blood supply to the distal limb of the affected area.

Objective:To construct a risk prediction and assessment system for incisional infection after spinal surgery.Methods:Based on the failure mode and effect analysis (FMEA), risk factors and assessment indicators of postoperative incisional infection in spinal surgery were sorted out through literature search followed by expert consultation using the Delphi expert consultation method. After three-level assessment indicators were selected according to their importance and expert opinions and assigned by different scores, a risk prediction and evaluation system was constructed for postoperative incisional infection after spinal surgery.Results:The 2 rounds of expert consultation questionnaire resulted in an effective response rate of 100%. The degree of expert consultation authority was 0.85, showing high reliability; the Kendall coordination coefficients of expert consultation ranged from 0.525 to 0.686, showing good coordination ( P<0.05). The three-level assessment indicators consisted of 3 primary, 18 secondary and 54 tertiary ones. After statistical analyses of the important risk indicators selected which consisted of 6 preoperative evaluation ones and 18 postoperative evaluation ones, 6 preoperative and 12 postoperative predictive indicators were obtained. The values of risk priority number (RPN) were calculated for high, medium and low risks for postoperative incisional infection using a semi-quantitative method. Conclusion:A self-designed system has been constructed for risk prediction and assessment of incisional infection after spinal surgery based on expert consultation and FMEA method.

To develop a specific, rapid, and convenient immunochromatography assay (ICA) to detect the rabies antibody in clinical sample from immuned dogs by rabies vaccine. Colloidal gold particles labeled with purified rabies virus (CVS11) were used as the detector reagent. The staphylococcal protein A (SPA) and pured rabbit anti-rabies virus IgG were blotted on the test and control regions of nitrocellulose membrane. Then the strip was assembled with sample pad, absorbing pad, and dorsal shield. The assay samples (261 dog's serum) were collected from Wildlife Rabies Disease Diagnostic Laboratories of Ministry of Agriculture in China, Institute of Military Veterinary, Academy of Military Medical Sciences and other six provinces, including rabies virus positive and negative serum. The performance of the strip was compared to fluorescent antibody virus neutralization test. The neutralizing antibody titer could be detected above 0.5 IU. The strip did not change of performance when stored at room temperature for 12 months. It may offer reference of neutralizing antibody titer level after dogs immuned rabies vaccine and determin whether the dogs need to be immuned again.
Animals ; Antibodies, Neutralizing ; analysis ; blood ; Antibodies, Viral ; analysis ; blood ; Dogs ; Gold Colloid ; Immunochromatography ; methods ; Rabies ; prevention & control ; veterinary ; Rabies Vaccines ; immunology ; Rabies virus ; immunology ; Reagent Strips ; Sensitivity and Specificity ; Vaccination

Objective:To analyze the epidemiological characteristics of a cluster of 5 confirmed COVID-19 cases related with the transmission in incubation period of initial case, and find out the infection source and transmission chain.Methods:According to "The Prevention and Control Protocol for Coronavirus Disease 2019 (Third Edition)" issued by the National Health Commission, a field epidemiological survey was conducted for the 5 cases in January 2020. Nasopharyngeal swabs and sputum samples were collected from them for the detection of 2019-nCoV by real time RT-PCR. Multi prevention and control measures were taken, such as tracking and screening close contacts, medical isolation observation, investigating the epidemiological link, analyzing transmission chain.Results:Case 1, who had common environmental exposure with other COVID-19 cases, got sick on 20 January, 2020 and was confirmed on 1 February. Case 2 became symptomatic on 22 January and was confirmed on 27 January. Case 3 got sick on 25 January and was confirmed on 30 January. Case 4 had illness onset on 20 January and was confirmed on 1 February. Case 5 got sick on 23 January and was confirmed on 31 January. Among the 5 cases, case 2 died and the illness of other cases were effectively controlled. After exclusion of other common exposure factors, case 1 had a 6-hour meeting with case 2 and case 3 on 19 January. Case 2 and case 3 might be infected by case 1 during the incubation period. It is the key point for epidemiological investigation.Conclusion:The epidemiological investigation indicates that the transmission might occur in the incubation period of COVID-19 case, close attention should be paid to it in future COVID-19 prevention and control.

OBJECTIVE: Pseudostellaria heterophylla has been paid more attention in recent years, mainly as a medicine food homology plant. The content determination of P. heterophylla is not specified in the Chinese Pharmacopoeia (version 2020). The environmental conditions in different production areas could exert an influence on the quality of P. heterophylla. The purpose of this study is to discriminate P. heterophylla collected from different geographical origins of China. METHODS: In this study, the content of polysaccharide in 28 batches of P. heterophylla was determined using phenol-sulfuric acid. HPLC fingerprints were established under optimised HPLC-PDA methods. Subsequently, the similarity analysis (SA) and the quantification of heterophyllin B were analyzed. The metabolites of P. heterophylla were identified and evaluated using UHPLC-Q Exactive HF orbitrap MS system. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), hierarchical cluster analysis (HCA) and orthogonal PLS-DA (OPLS-DA) were performed based on all peak areas. RESULTS: The polysaccharide content in Guizhou and Jiangsu was higher than that of other production areas, which varied significant from different origins. While the content of heterophyllin B in Anhui and Jiangsu was high. The correlation coefficients of HPLC fingerprints for 28 batches samples ranged from 0.877 to 0.990, and the characteristic map can be used to identify and evaluate the quality of P. heterophylla. The samples from Fujian, Guizhou, Jiangsu provinces can be relatively separated using multivariate statistical analysis including PCA, PLS-DA, HCA, OPLS-DA, indicating that their metabolic compositions were significantly different. Ultimately, a total of 15 metabolites which were filtrated by a VIP-value > 1 and a P-value < 0.05 associated with the separation of different origins were identified. CONCLUSION HPLC fingerprint was established to evaluate the quality and authenticity of P. heterophylla. The present work showed that the difference of geographic distributions had an influence on the internal chemical compositions. A sensitive and rapid untargeted metabolomics approach by UHPLC-Q Exactive HF orbitrap MS was utilized to evaluate P. heterophylla from different origins in China for the first time. Overall, this study provides insights to metabolomics of P. heterophylla and supplies important reference values for the development of functional foods.