[Risk factors for complications of endoscopic full-thickness resection of upper gastrointestinal submucosal tumors].

Objective: To analyze the risk factors for complications of endoscopic full-thickness resection (EFTR) of upper gastrointestinal submucosal tumors (SMTs). Methods: This was a retrospective observational study. The indications for EFTR included: (1) SMTs originating from the muscularis propria layer and growing out of the cavity or infiltrating the deep part of the muscularis propria layer; (2) SMTs diameter <5 cm; and (3) tumor identified as closely adherent to the serous layer during endoscopic submucosal dissection or endoscopic mucosal resection. This study included patients with SMTs originating from the muscularis propria layer in upper digestive tract, diagnosed preoperatively by endoscopic ultrasonography or computed tomography, who were successfully treated with EFTR. Those with incomplete clinical data were excluded. The clinical data of 154 patients with upper gastrointestinal SMTs who underwent EFTR at the Department of Gastroenterology, First Affiliated Hospital of Soochow University from January 2016 to January 2022 were retrospectively analyzed. Post-EFTR complications (such as delayed perforation, delayed bleeding, and postoperative infection, including electrocoagulation syndrome) were monitored and the risk factors for them were analyzed. Results: Among the 154 study patients, 33 (21.4%) developed complications, including delayed bleeding in three (1.9%), delayed perforation in two (1.3%), and postoperative infection in 28 (18.2%). One patient with bleeding was classified as having a major complication (hospitalized for more than 10 days because of complication). According to univariate analysis, complication was associated with tumor diameter >15 mm, operation time >90 minutes, defect closure method(purse string suture), and diameter of resected specimen ≥20 mm (all P<0.05). Multivariate logistic regression analysis showed that operation time >90 minutes (OR=6.252, 95%CI: 2.530-15.446, P<0.001) and tumor diameter >15 mm (OR=4.843, 95%CI: 1.985-11.817, P=0.001) were independent risk factors for complications after EFTR in patients with upper gastrointestinal SMTs. The independent risk factors for postoperative infection in these patients were operation time>90 minutes (OR=4.993, 95%CI:1.964-12.694, P=0.001) and purse string suture (OR=7.142, 95%CI: 1.953-26.123, P=0.003). Conclusion: Patients with upper gastrointestinal SMTs undergoing EFTR with tumor diameter >15 mm or operation time >90 minutes have a significantly increased risk of postoperative complications. Postoperative monitoring is important for these patients with SMTs.

Whole Body Center of Mass Feedback in a Reflex-Based Neuromuscular Model Predicts Ankle Strategy During Perturbed Walking.

Active prosthetic and orthotic devices have the potential to increase quality of life for individuals with impaired mobility. However, more research into human-like control methods is needed to create seamless interaction between device and user. In forward simulations the reflex-based neuromuscular model (RNM) by Song and Geyer shows promising similarities with real human gait in unperturbed conditions. The goal of this work was to validate and, if needed, extend the RNM to reproduce human kinematics and kinetics during walking in unperturbed and perturbed conditions. The RNM was optimized to reproduce joint torque, calculated with inverse dynamics, from kinematic and force data of unperturbed and perturbed treadmill walking of able-bodied human subjects. Torques generated by the RNM matched closely with torques found from inverse dynamics analysis on human data for unperturbed walking. However, for perturbed walking the modulation of the ankle torque in the RNM was opposite to the modulation observed in humans. Therefore, the RNM was extended with a control module that activates and inhibits muscles around the ankle of the stance leg, based on changes in whole body center of mass velocity. The added module improves the ability of the RNM to replicate human ankle torque response in response to perturbations. This reflex-based neuromuscular model with whole body center of mass velocity feedback can reproduce gait kinetics of unperturbed and perturbed gait, and as such holds promise as a basis for advanced controllers of prosthetic and orthotic devices.

Symbitron Exoskeleton: Design, Control, and Evaluation of a Modular Exoskeleton for Incomplete and Complete Spinal Cord Injured Individuals.

In this paper, we present the design, control, and preliminary evaluation of the Symbitron exoskeleton, a lower limb modular exoskeleton developed for people with a spinal cord injury. The mechanical and electrical configuration and the controller can be personalized to accommodate differences in impairments among individuals with spinal cord injuries (SCI). In hardware, this personalization is accomplished by a modular approach that allows the reconfiguration of a lower-limb exoskeleton with ultimately eight powered series actuated (SEA) joints and high fidelity torque control. For SCI individuals with an incomplete lesion and sufficient hip control, we applied a trajectory-free neuromuscular control (NMC) strategy and used the exoskeleton in the ankle-knee configuration. For complete SCI individuals, we used a combination of a NMC and an impedance based trajectory tracking strategy with the exoskeleton in the ankle-knee-hip configuration. Results of a preliminary evaluation of the developed hardware and software showed that SCI individuals with an incomplete lesion could naturally vary their walking speed and step length and walked faster compared to walking without the device. SCI individuals with a complete lesion, who could not walk without support, were able to walk with the device and with the support of crutches that included a push-button for step initiation Our results demonstrate that an exoskeleton with modular hardware and control allows SCI individuals with limited or no lower limb function to receive tailored support and regain mobility.

Neuromuscular Controller Embedded in a Powered Ankle Exoskeleton: Effects on Gait, Clinical Features and Subjective Perspective of Incomplete Spinal Cord Injured Subjects.

Powered exoskeletons are among the emerging technologies claiming to assist functional ambulation. The potential to adapt robotic assistance based on specific motor abilities of incomplete spinal cord injury (iSCI) subjects, is crucial to optimize Human-Robot Interaction (HRI). Achilles, an autonomous wearable robot able to assist ankle during walking, was developed for iSCI subjects and utilizes a NeuroMuscular Controller (NMC). NMC can be used to adapt robotic assistance based on specific residual functional abilities of subjects. The main aim of this pilot study was to analyze the effects of the NMC-controlled Achilles, used as an assistive device, on chronic iSCI participants' performance, by assessing gait speed during 10-session training of robot-aided walking. Secondary aims were to assess training impact on participants' motion, clinical and functional features and to evaluate subjective perspective in terms of attitude towards technology, workload, usability and satisfaction. Results showed that 5 training sessions were necessary to significantly improve robot-aided gait speed on short paths and consequently to optimize HRI. Moreover, the training allowed participants who initially were not able to walk for 6 minutes, to improve gait endurance during Achilles-aided walking and to reduce perceived fatigue. Improvements were obtained also in gait speed during free walking, thus suggesting a potential rehabilitative impact, even if Achilles-aided walking was not faster than free walking. Participants' subjective evaluations indicated a positive experience.

Gait training with Achilles ankle exoskeleton in chronic incomplete spinal cord injury subjects.

Powered exoskeletons (EXOs) have emerged as potential devices for Spinal Cord Injury (SCI) to support the intervention of physical therapists during therapy (rehabilitation EXOs) as well as to assist lower limb motion during the daily life (assistive EXOs). Although the ankle is considered a key joint for gait restoration after SCI, very few ankle exoskeletons were developed and tested in incomplete SCI (iSCI) population. Among those, the Achilles ankle exoskeleton is the only one embedding a Controller inspired by the neuromuscular system (NeuroMuscular Controller, NMC). In a previous study we demonstrated that a period dedicated to train iSCI subjects in using the Achilles EXO as an assistive aid, improved robot-aided walking speed and surprisingly also generated a positive trend in free walking speed on long and short distances thus suggesting a possible unexpected rehabilitation effect. To further investigate this result, a case-control longitudinal study was conducted in the present work. The aim of this study was to test the hypothesis that Achilles-aided training could improve performance of free walking of chronic iSCI people more than conventional intensity-matched gait rehabilitation. Before and after conventional and robot-aided rehabilitation a number of variables were analyzed, including spatiotemporal parameters, joint kinematics, ground reaction forces, muscle force, spasticity and its related symptoms, balance and personal experience about the training. Results showed that only the NMC-controlled Achilles training allowed participants to significantly walk faster, with a longer step length and a reduced gait cycle time. A slight force and spasticity improvements were also experienced. In terms of subjects' personal experience, Achilles training was perceived more interesting and less physically demanding than conventional rehabilitation.

Duration of EEG suppression does not predict recovery time or degree of cognitive impairment after general anaesthesia in human volunteers.

BACKGROUND: Burst suppression occurs in the EEG during coma and under general anaesthesia. It has been assumed that burst suppression represents a deeper state of anaesthesia from which it is more difficult to recover. This has not been directly demonstrated, however. Here, we test this hypothesis directly by assessing relationships between EEG suppression in human volunteers and recovery of consciousness. METHODS: We recorded the EEG of 27 healthy humans (nine women/18 men) anaesthetised with isoflurane 1.3 minimum alveolar concentration (MAC) for 3 h. Periods of EEG suppression and non-suppression were separated using principal component analysis of the spectrogram. After emergence, participants completed the digit symbol substitution test and the psychomotor vigilance test. RESULTS: Volunteers demonstrated marked variability in multiple features of the suppressed EEG. In order to test the hypothesis that, for an individual subject, inclusion of features of suppression would improve accuracy of a model built to predict time of emergence, two types of models were constructed: one with a suppression-related feature included and one without. Contrary to our hypothesis, Akaike information criterion demonstrated that the addition of a suppression-related feature did not improve the ability of the model to predict time to emergence. Furthermore, the amounts of EEG suppression and decrements in cognitive task performance relative to pre-anaesthesia baseline were not significantly correlated. CONCLUSIONS: These findings suggest that, in contrast to current assumptions, EEG suppression in and of itself is not an important determinant of recovery time or the degree of cognitive impairment upon emergence from anaesthesia in healthy adults.

A shared neural integrator for human posture control.

Control of standing posture requires fusion of multiple inputs including visual, vestibular, somatosensory, and other sensors, each having distinct dynamics. The semicircular canals, for example, have a unique high-pass filter response to angular velocity, quickly sensing a step change in head rotational velocity followed by a decay. To stabilize gaze direction despite this decay, the central nervous system supplies a neural "velocity storage" integrator, a filter that extends the angular velocity signal. Similar filtering might contribute temporal dynamics to posture control, as suggested by some state estimation models. However, such filtering has not been tested explicitly. We propose that posture control indeed entails a neural integrator for sensory inputs, and we test its behavior with classic sensory perturbations: a rotating optokinetic stimulus to the visual system and a galvanic vestibular stimulus to the vestibular system. A simple model illustrates how these two inputs and body tilt sensors might produce a postural tilt response in the frontal plane. The model integrates these signals through a direct weighted sum of inputs, with or without an indirect pathway containing a neural integrator. Comparison with experimental data from healthy adult subjects (N = 16) reveals that the direct weighting model alone is insufficient to explain resulting postural transients, as measured by lateral tilt of the trunk. In contrast, the neural integrator, shared by sensory signals, produces the dynamics of both optokinetic and galvanic vestibular responses. These results suggest that posture control may involve both direct and indirect pathways, which filter sensory signals and make them compatible for sensory fusion.NEW & NOTEWORTHY Control of standing posture requires fusion of multiple inputs including visual, vestibular, somatosensory, and other sensors, each having distinct dynamics. We propose that postural control also entails a shared neural integrator. To test this theory, we perturbed standing subjects with classic sensory stimuli (optokinetic and galvanic vestibular stimulation) and found that our proposed shared filter reproduces the dynamics of subjects' postural responses.

[Radioimmunoimaging assay of ovarian tumor with 99mTc labeled anti-carcinoembryonic antigen monoclonal antibody].

Radioimmunoimaging (RI I) assay with 99mTc labeled anti-CEA monoclonal antibody was performed in 31 patients with suspected primary or recurrent malignant ovarian tumor. The radiation dose raging from 920MBq to 110MBq(1mgIgG) was administered i.v. for each patient. Anterior-posterior views of the pelvis and abdomen were obtained routinely with gamma-camera during 18-24 hour after the application of antibody. The results of RII were compared with the findings in operation or CT examination. Sensitivity in diagnosis was 100% (13/13), specificity was 94%(16/17) and metastatic foci sensitivity was 63%(10/16). The serum CA125 in this study appeared to be correlated with the results of RII. However, in 2 patients with normal serum CA125 titers RII revealed true positive. The preliminary clinical results of RII with 99mTc-MAb showed that RII is a promising method for the detection of malignant ovarian tumors.

[Preliminary report on the application of colposcopy in screening of cervical carcinoma].

Four hundred and fifty six women were examined by colposcopy in a high incidence area of cervical cancer from May 1988 to June 1990. In the 330 evaluable cases, colposcopic impression correlated accurately with the histologic diagnosis (including difference of one degree) in 95.2% of the cases, while cytology in 71.2% only. Directed biopsies under colposcopy were compared with surgical specimen of 36 patients and the diagnostic accurate rate was 97.2%. The confirmation rate between colposcopy and endocervical curettage was 89.2%. Among 79 patients with cervical cancer, the results obtained by colposcopy and cytology did not show a statistically significant difference (P = 0.9691). However, colposcopy was superior to cytology with regard to the sensitivity of detection of early cervical cancer (88.5% vs 54.4%). When colposcopy was combined with cytology, the diagnostic accurate rate of cervical cancer was further improved (94.9%). This study demonstrated that colposcopy is another reliable method for the diagnosis of cervical cancer and precancerous lesions. The combination of colposcopy with cytology may not only improve the diagnostic accuracy, but also reduce their false negative rate. We would suggest application of colposcopy plus endocervical curettage combined with histopathological examination as an effective approach to improve the quality of screening of cervical cancers.

[Relation between female genital human papilloma virus (HPV) infection and cancer of uterine cervix in Xiang Yuan County, a high incidence area of cervical carcinoma].

Six thousand seven hundred and ten women were screened in a high incidence area, Xiang Yuan County, Shanxi province to study the relation between cervical cancer and female genital HPV infection (HPVI). Invasive cervical cancer was diagnosed by histopathology in 15 subjects, CIS in 44 and HPVI in 110. Morphologic features of HPVI were found in 23.9% (80/334) of the biopsies from abnormal cervix and lower genital tract. A total of 20.3% lesions had morphologic feature of HPVI associated with CIN, CIS and ICC. One hundred sixty eight biopsies were assayed for the presence of HPV 6B/11, 16, 18 DNA by dot blot hybridization. Altogether, 40.5% biopsies were found to have HPV DNA. The positivities of HPV DNA in cancerous and non-cancerous groups were 62.8% and 32.8%, respectively. The positivity of HPV DNA and the grade of cervical lesions showed a statistically significant correlation (P less than 0.01). Of those with positive HPV DNA HPV 16 was the most frequent type (66.2%). This study further demonstrated that Xiang Yuan is one of the highest risk areas of cervical cancer in China. It is suggested that there is a close association between cervical cancer and HPV infection, especially of type HPV 16, of the female genital tract.

Detection of HPV-16 DNA in cervical carcinoma by paraffin section in situ hybridization.

Thirty-eight cervical carcinomas and one cervical condyloma were examined for the presence of human papillomavirus type 16 (HPV-16) DNA using 3H-dcTP-labelled HPV-16 DNA probe in paraffin section in situ hybridization and dot blot hybridization (Tm-17 degrees C). The results showed that HPV-16 DNA positive rate in our series was about 74.4% (29/39) as determined by paraffin section in situ hybridization and about 71.8% (28/29) by dot blot hybridization. There was no significant difference between the two methods. We thus confirmed that paraffin section in situ hybridization is an informative, reliable, and sensitive method for the diagnosis of cervical HPV infection.

Kinetics of IgE antibody response to trichosanthin alpha-momorcharin and beta-momorcharin in mice.

Allergenicity of three plant abortifacient proteins, trichosanthin (TCS), alpha-momorcharin (alpha-MMC) and beta-momorcharin (beta-MMC) and the kinetics of IgE antibody response against these proteins were studied in C57BL/6N and BALB/cAn mice. These proteins were purified from Chinese medicinal herbs, characterized by biochemical and immunological procedures and found to be homogeneous by PAGE, SDS-PAGE and immunoelectrophoresis. The results obtained were summarized as follows: 1) different levels of IgE antibody responses against TCS, alpha-MMC and beta-MMC were induced when they were injected i.p. as antigen adsorbed onto AI(OH)3 gel into BALB/cAn or C57BL/6N mice on day 0 and day 28; 2) the allergenicity of the proteins was in the order of beta-MMC greater than alpha-MMC greater than TCS; 3) two injections of 10 micrograms or 50 micrograms of TCS or alpha-MMC given at 4 weeks interval without adjuvant elicited a low or undetectable PCA titer, while the same dose given weekly for 5 weeks resulted in high levels of IgE production; and 4) on the basis of PCA observations, no cross immunological reactivity among these three proteins was found, it seemed to support that TCS, alpha-MMC and beta-MMC may be alternately used for inducing abortion.

In situ hybridization analysis of HPV DNA in cervical precancer and cervical cancers from China.

A series of 103 cervical biopsies derived from 103 women during July 1958 to September 1963 from Beijing, China were investigated with in situ hybridization for the presence of HPV6, 11, 16, 18, 31 and 33 DNA. The mean age of the patients was 46.1 + 10.6 years with a range of 24-74 years. Morphological features of HPV infection were found in 80 (77.7%) biopsies. Invasive cervical cancer was diagnosed in 43 biopsies and cervical intraepithelial neoplasia CIN I, CIN II and CIN III in 9, 9, and 27 cases, respectively. A total of 63.1% (65/103) of the lesions had morphological features of HPV infections associated with CIN or invasive carcinomas. Altogether, 31.1% (32/103) of the biopsies were shown to contain HPV DNA. Of the cases showing HPV morphology, 43.1% were HPV DNA positive. HPV16 (30/32) was the most frequent type, followed by HPV11 and 18, whereas no lesions with HPV6, 31 or 33 were found. A total of 19/43 (44.2%) of the invasive carcinomas contained HPV DNA. HPV DNA positivity and the grade of CIN showed a statistically significant correlation (P = 0.0011). Our study demonstrated the presence of HPV in cervical lesions among Chinese women in the late 1950's and early 1960's when a single sexual partner was the rule and also supports the concept that HPV has as an important etiological role in cervical cancer, the highest risk being associated with HPV type 16. The applicability of in situ hybridization in retrospective assessment is emphasized.

[Flow cytometry (FCM) in DNA content assay of normal and malignant epithelial cells of human uterine cervix and the prognostic significance of DNA content--II. Results].

Previous studies on cervical cancer using microspectrophotometric technique to measure DNA content of the cancer cells had indicated that the tumor ploidy is an important prognostic variable and that tumors with a DNA index less than 1.55 have a worse prognosis than those with higher DNA index. But there are conflicting results in the other studies using flow cytometer. In this paper, a retrospective analysis on the tumor ploidy of paraffin-embedded tissues using flow cytometer before treatment in 88 patients with cervical cancer was carried out. The results indicate that tumors with a DNA index over 1.5 have a higher recurrence rate and lower survival rate in stage I patients as compared with tumors having a lower DNA index (P less than 0.05). No correlation is found between clinical stage, tumor size, lymph node metastasis, histopathology and DNA index. However, prognosis is related to many factors, such as tumor differentiation, treatment modality etc., a multiple regression analysis of the different prognostic variables and further studies in this aspect are necessary.

[Supraclavicular lymph node metastasis from carcinoma of the uterine cervix after radiotherapy--analysis of 219 patients].

From Mar. 1958 to Dec. 1985, 13547 patients with cervical cancer in stages I-III were treated by radiotherapy in our hospital. Supraclavicular lymph node metastasis developed in 219 (1.62%), 83.1% on the left, 7.7% on the right and 9.13% bilateral. 61.2% of the metastasis occurred within 2 years and 86.75% within 5 years after radiotherapy. The majority of these patients (88.3%, 191/215), except 4 who are still being followed, had died within 1.5 years of metastasis with a mean survival of 9.3 months. If radiotherapy in adequate dose is given to the supraclavicular metastatic area, the mean survival can be prolonged for 3.7 months. The prognosis is very poor for these patients no matter what the clinical stage is or when the metastasis develops. The more advanced clinical stage, the higher metastasis rate (P less than 0.001). In this series, 47/219 (21.5%) were found to have concurrent metastasis to the other organs.

[Application of monoclonal antibody OC 125 in gynecological oncology].

This study was undertaken to determine whether the measurement of CA125 could effect an early diagnosis and a method for monitoring the course of gynecologic tumors. CA 125 in serum of 195 patients, including 15 apparently healthy women; 39 benign gynecologic tumors; 2 borderline ovarian tumors; 139 malignancies were measured by CENTOCOR cancer antigen 125 kits. Diagnosis of all patients was confirmed by pathology. None of the healthy women; 10% of benign tumors; 78% of epithelial ovarian cancers; 31% of endometrial adenocarcinomas and one out of five adenocarcinoma of uterine cervix had CA 125 level over 65 U/ml. In addition, 23 cases of ovarian cancer were monitored serially up to 9 months. In more than 80% of these patients, CA 125 levels were correlated with the regression or progression of the disease. The significance of this assay for early diagnosis and monitoring the course of ovarian cancer is discussed. It is considered that CA 125 is a promising and useful antigenic marker for monitoring the course of ovarian cancers.

[Report on 114 primary vaginal carcinomas].

114 patients with primary carcinoma of the vagina were treated in our hospital from 1958 to 1978. It accounted for 0.83% of all gynecological malignant tumors in the same period. The youngest was 26 years of age, the oldest 75. Patients 40-59 years comprised 61.4%. 33% of patients had wedding age under 17. 63.4% had more than 4 pregnancies and 58.4% gave more than 4 births. 89.69% was diagnosed as squamous cell carcinoma, 7.2% as adenocarcinoma, 2.06% as undifferentiated carcinoma and 1 as embryonic carcinoma. The tumor occurred frequently in the upper third and posterior wall of the vagina (60% and 68%). In this series, there were 21 stage I, 29 stage II, 61 stage III and 3 stage IV lesions. 110 patients were treated by radiotherapy in different schemes. Intracavitary radium or caesium plus 60Co external irradiation by four fields gave better result with a 5 year survival rate of 66.1%. Only 2 out of 12 patients were cured by 60Co rotation alone but if supplemented by intracavitary radium or caesium, the cure rate was increased. The 5 year survival rate was 71.4% for stage I, 62.1% for stage II, 42.6% for stage III and O for stage IV. After the radiotherapy, rectovaginal fistula developed in 1 patient, vesicovaginal fistula in 1. 14% was complicated with rectal bleeding and 8.18% with hematuria.

[Relation between human papillomavirus (HPV) and cancer of uterine cervix].

HPV-DNA fragments were detected in biopsy specimens (29 cases of cancer of uterine cervix, 2 cervical dysplasia and 9 normal cervix) using DNA hybridization technique. It was demonstrated that 52% of biopsy specimens of the cancer of uterine cervix was positive for HPV 16 DNA probe, while 9% was positive for HPV 18 DNA probe. 11% of non-cancerous biopsy specimens had a positive result for HPV 16 DNA probe. It was also demonstrated that the positive rate of HPV 16 DNA was 75% in grossly cauliflower and nodular type tumors but only 25% in erosion type. It seems that the positive rate of HPV 16 DNA is correlated to gross appearance of the tumor. The positive rates of HPV 16 DNA were different in 6 provinces in China. It was 64% in Shanxi Province, a high incidence area but 36% in Sichuan Province, a low incidence area. These results suggest that the carcinogenesis of cancer of the uterine cervix, be related to HPV infection.