[Computer-vision-based artificial intelligence for detection and recognition of instruments and organs during radical laparoscopic gastrectomy for gastric cancer: a multicenter study]

Objective: To investigate the feasibility and accuracy of computer vision-based artificial intelligence technology in detecting and recognizing instruments and organs in the scenario of radical laparoscopic gastrectomy for gastric cancer. Methods: Eight complete laparoscopic distal radical gastrectomy surgery videos were collected from four large tertiary hospitals in China (First Medical Center of Chinese PLA General Hospital [three cases], Liaoning Cancer Hospital [two cases], Liyang Branch of Jiangsu Province People's Hospital [two cases], and Fudan University Shanghai Cancer Center [one case]). PR software was used to extract frames every 5-10 seconds and convert them into image frames. To ensure quality, deduplication was performed manually to remove obvious duplication and blurred image frames. After conversion and deduplication, there were 3369 frame images with a resolution of 1,920×1,080 PPI. LabelMe was used for instance segmentation of the images into the following 23 categories: veins, arteries, sutures, needle holders, ultrasonic knives, suction devices, bleeding, colon, forceps, gallbladder, small gauze, Hem-o-lok, Hem-o-lok appliers, electrocautery hooks, small intestine, hepatogastric ligaments, liver, omentum, pancreas, spleen, surgical staplers, stomach, and trocars. The frame images were randomly allocated to training and validation sets in a 9:1 ratio. The YOLOv8 deep learning framework was used for model training and validation. Precision, recall, average precision (AP), and mean average precision (mAP) were used to evaluate detection and recognition accuracy. Results: The training set contained 3032 frame images comprising 30 895 instance segmentation counts across 23 categories. The validation set contained 337 frame images comprising 3407 instance segmentation counts. The YOLOv8m model was used for training. The loss curve of the training set showed a smooth gradual decrease in loss value as the number of iteration calculations increased. In the training set, the AP values of all 23 categories were above 0.90, with a mAP of 0.99, whereas in the validation set, the mAP of the 23 categories was 0.82. As to individual categories, the AP values for ultrasonic knives, needle holders, forceps, gallbladders, small pieces of gauze, and surgical staplers were 0.96, 0.94, 0.91, 0.91, 0.91, and 0.91, respectively. The model successfully inferred and applied to a 5-minutes video segment of laparoscopic gastroenterostomy suturing. Conclusion: The primary finding of this multicenter study is that computer vision can efficiently, accurately, and in real-time detect organs and instruments in various scenarios of radical laparoscopic gastrectomy for gastric cancer.

[Incidence of postoperative complications in Chinese patients with gastric or colorectal cancer based on a national, multicenter, prospective, cohort study]

Objective: To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications. Methods: This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression. Results: The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion: Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

[Predictive value of hemoglobin glycation index for chronic kidney disease]

Objective: To investigate the influence of hemoglobin glycation index (HGI) on the risk of incident chronic kidney disease (CDK) among nondiabetic patients. Methods: Prospective cohort study. At baseline, a total of 7 407 nondiabetic patients without a history of CKD from Pingguoyuan Community of the Shijingshan District in Beijing were included from December 2011 to August 2012, who were then divided into three groups according to the tertiles of their baseline HGI levels. The CKD incidence rate was compared among the different HGI groups at last follow-up. Cox multivariable regression was applied to evaluate whether HGI measures predicted CKD risk. Test for trend across tertiles were examined using ordinal values in separate models. Results: The mean age of the subjects was (56.4±7.5) years, and 4 933 (66.6%) were female. At mean follow-up of 3.23 years, 107 (1.4%) individuals developed CKD. The incidence of CKD was gradually increasing from the low to high HGI groups [1.1% (28/2 473) vs. 1.2% (31/2 564) vs. 2.0% (48/2 370), P=0.016]. In the multivariate Cox regression analysis, after adjustment for potential confounders, the high HGI group had a 68.5% increased risk of CKD compared with the low HGI group (HR=1.685, 95%CI 1.023 to 2.774). CKD risk increased with increasing HGI tertiles (P for trend=0.028). Conclusion: High HGI is associated with an increased risk for CKD in the nondiabetic population, indicating that HGI may help identify individuals at high risk for CKD.

[Meta-analysis of the interventional effects of music therapy on pain and anxiety of burn patients in wound dressing change]

Objective: To evaluate the interventional effects of music therapy on pain and anxiety of burn patients in wound dressing change. Methods: The meta-analysis method was adopted. Databases including China National Knowledge Internet, Wanfang Database, and VIP database were retrieved with the search terms in Chinese version of ", , /, /", and PubMed, Embase, and Cochrane Library were retrieved with the search terms in English version of "music, burn, dressing change/wound dressing, pain/ache/sore" to obtain the publicly published randomized controlled trials on the application of music therapy for wound dressing change in burn patients from the establishment of each database to May 2021. The outcome indexes included pain score/percentage and anxiety score after dressing change. Rev Man 5.4 and Stata 14.0 statistical software were used to conduct a meta-analysis of eligible studies. Results: A total of 520 burn patients from 7 studies were included, including 260 patients in music therapy group who received music therapy and 260 patients in routine dressing change group who received routine dressing change. The bias risk of all the 7 included studies was uncertain. Compared with those in routine dressing change group, the pain percentages (relative risk=0.06, 95% confidence interval=0.01-0.41, P<0.01) and pain scores after dressing change (standardized mean difference (SMD)=-0.91, 95% confidence interval=-1.61--0.22, P<0.05) of patients in music therapy group were significantly lower. Subgroup analysis showed that music type and timing of intervention might be the source of heterogeneity in pain scores after dressing change. The anxiety scores of patients in music therapy group were significantly lower than those in routine dressing change group (SMD=-0.64, 95% confidence interval=-1.09--0.19, P<0.01). There was no publication bias in pain or anxiety scores after dressing change. Conclusions: Music therapy can relieve the pain and anxiety of burn patients during dressing change.

Proteomic biomarkers associated with incident heart failure and frailty in late life

Background

Heart failure (HF) and frailty are highly prevalent in late life and commonly co-exist, but the mechanisms underlying their bi-directional relationship are incompletely understood. This study aimed to identify shared molecular pathways associated with incident HF and frailty in late life.

Methods

Among participants in the Atherosclerosis Risk in Communities (ARIC) study, a communit-based cohort study in the United States, 4,877 plasma proteins were measured using an aptamer-affinity assay (Somascan v4) at study Visit 3 (V3; 1993–1994; n=10,368, age 60±6 years; 822 incident HF events) and at study Visit 5 (V5; 2011–2013; n=3,908, age 75±5 years; 336 incident HF events). Frailty was assessed at V5 using Fried criteria, which incorporates gait speed, grip strength, low energy expenditure, weight loss, and exhaustion. We examined the association of proteins at V3 with incident HF after V3 with Bonferroni corrected P&lt;0.05 using multivariable Cox proportional hazard regression models. For HF-associated proteins at V3, we assessed the association of V5 protein levels with incident HF after V5. For the resulting HF-associated proteins, multivariable logistic regression was used to assess associations of V5 protein values with prevalent frailty at V5 (n=223 cases) and with incident frailty by study Visit 6 (2016–2018; n=152 incident cases). All models adjusted for age, sex, race, hypertension, diabetes, cardiovascular disease, BMI, atrial fibrillation, and stroke. The set of HF-related proteins that associated with incident frailty at FDR &lt;0.05 using Benjamini-Hochberg correction was tested for pathway enrichment using the Reactome database.

Results

Of 289 proteins associated with incident HF post-V3 at p&lt;1.0x10–5 (0.05/4,877), 84 were significantly associated with incident HF post-V5 at p&lt;1.7x10–4 (0.05/289). Among 4,131 HF-free participants at V5, 48 of these 84 HF-associated proteins associated with prevalent frailty at p&lt;5.9x10–4 (0.05/84). Among Visit 5 participants who completed a frailty assessment and were free of both prevalent HF and frailty (n=3,908), 31of 48 candidate proteins were also significantly associated with incident frailty at FDR 0.05, 18 of which were significantly associated with incident frailty at p&lt;1.0x10–3 (0.05/48; Figure 1). The 31 proteins associated with incident frailty at FDR 0.05 enriched for collagen biosynthesis, formation, and trimerization (COL28A1, COL6A3, EFEMP1), and cytokine immune pathways and TNF receptor binding (TNFRSF1A and B, VEGFA, B2M, and HAVCR2) in pathway enrichment analysis.

Conclusions

Collagen metabolism and immune pathways may be shared biologic pathways between HF and frailty in late-life.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The Atherosclerosis Risk in Communities study has been funded in whole or in part with Federal funds from the National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services.

[Dilemmas in definition and classification of adenocarcinoma of esophagogastric junction: from history to current status]

In recent years, adenocarcinoma of esophagogastric junction (AEG) has received increased attention from the academic community. However, the esophagogastric junction (EGJ) straddles two anatomical regions: the thoracic cavity and the abdominal cavity. The histological features of the EGJ are different from those of the esophagus and stomach. There are general disagreements among the related disciplines regarding the definition and classification of AEG. By summarizing the views of different disciplines, including endoscopy, radiography, and pathology, a more comprehensive definition of the EGJ was formulated in the Japanese Classification of Gastric Carcinoma (the 15th edition), and the principle of endoscopic diagnostic priority was established. In recent years, with the development of physiological and anatomical studies, the EGJ has gradually expanded conceptually into a complex functional anatomical region covering the distal esophagus to the proximal stomach. The venous and lymphatic vessels in the EGJ are characterized by bidirectional flow, which is an important anatomical basis for the invasion and metastasis patterns of tumors in this region. The clinical practice of EGJ cancer has been promoted by the creation of Nishi and Siewert classification systems. With the support of a series of clinical studies for its scientificity and effectiveness, the Siewert classification is widely accepted by the international community, and successively introduced into major international practice guidelines. In general, the staging and management of Siewert Ⅰ and Ⅱ AEG are recommended as esophageal cancer, while Siewert Ⅲ AEG is recommended for gastric cancer. However, in the Japanese guidelines for the treatment of esophageal and gastric cancers, the Nishi classification is still used to define and classify EGJ cancer. Recent year, a Chinese consensus on the surgical treatment of AEG was formulated by multidisciplinary experts. The main controversies were summarized in the consensus, and proposals that incorporate the domestic situation were also presented. At present, only by returning to the basic anatomical and physiological perspectives, strengthening multidisciplinary communication and cooperation, and with the help of emerging bioinformatics, digital, and material technology, can it be possible to get out of the dilemma faced by traditional AEG classification and staging system.

Di-(2-ethylhexyl) phthalate exposure links to inflammation and low bone mass in premenopausal and postmenopausal females: Evidence from ovariectomized mice and humans

OBJECTIVE

Phthalates induce inflammation and are ubiquitously used in daily life. We aim to study the impact of di-(2-ethylhexyl) phthalate (DEHP) exposure on inflammation and osteoporosis in premenopausal and postmenopausal females.

METHODS

Female 8-week-old C57BL/6JNarl mice received an ovariectomy (OVX) or a sham operation and were fed with DEHP or vehicle by oral gavage for 4 or 8 weeks. Their femurs were isolated for micro-computed tomography, and their serum was collected for inflammatory cytokine assays. Correlations between urinary phthalate metabolites and the lumbar spine bone mineral density (BMD) in premenopausal and postmenopausal volunteers were performed.

RESULTS

Among the OVX mice treated for 4 weeks, significant lower bone volume, bone volume/tissue volume, and trabecular number but significant higher trabecular bone pattern factor and structure model index were identified in the mice treated with DEHP than with vehicle. The OVX mice treated with DEHP for 4 weeks had significantly higher serum interleukin (IL)-1β, IL-10, IL-17A, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and Dickkopf-1 levels than those treated with vehicle. The sham mice treated with DEHP for 8 weeks showed an impaired femur trabecular microstructure and had significantly higher serum IL-1β, IL-6, IL-10, IL-17A, IFN-γ, and TNF-α than those treated with vehicle. DEHP metabolites were inversely correlated with the BMD of premenopausal women and the T-score of postmenopausal women.

CONCLUSION

DEHP treatment in OVX and sham mice results in osteoporosis and impairs the microstructure of the femur trabecula through inflammation. Phthalate exposure negatively affects the bone mass in both premenopausal and postmenopausal women. Thus, long-term avoidance is suggested.

[Application value and difficulty analysis of fluorescence laparoscopy in lymphadenectomy of gastric cancer]

Gastric cancer is one of the most common gastrointestinal malignancies, and the incidence and mortality of gastric cancer remain high in China. In recent years, with the rapid popularization of laparoscopic technology, fluorescent laparoscopic technology is increasingly getting mature, providing a new method for accurate clinical tracing of lymph nodes and prediction of tumor metastasis lymph nodes. A large number of scientific research experiments and clinical trials have shown that, laparoscopic lymph node diagnosis technology based on the fluorescent indocyanine green (ICG) can significantly improve the efficiency of lymphadenectomy and prediction accuracy of lymph node metastasis, and can reveal a more accurate scope of lymphadenectomy in gastric cancer for surgeons, so as to avoid excessive adenectomy as well as iatrogenic injuries on patients. Although the status of the technology in gastric cancer surgery mentioned above continues improving, the overall operation process details of ICG fluorescence imaging, standardized fluorescence detecting equipment, and postoperative pathological examination process still need to be further optimized.

[Laparoscopic proximal gastrectomy and lymph node resection in adenocarcinoma of the esophagogastric junction]

The proportion of adenocarcinoma of the esophagogastric junction (AEG) in gastric cancer is gradually increasing. Due to the unique anatomical structure and biological characteristics of the tumor at this site, AEG has a certain degree of complexity in many aspects of diagnosis and treatment, which brings difficulties to the operation method, the selection of the resection range, the lymph node dissection and the treatment decision-making. Therefore, AEG has always been the focus of academic debate. With the development of minimally invasive surgery in recent years, laparoscopic technology has been increasingly mature and widely used in the treatment of gastrointestinal tumors. Compared with distal gastric cancer, the minimally invasive treatment of AEG is in a lagging state, and there are also a series of problems that have not yet reached a consensus. This article reviews and summarizes the recent research progress in two aspects: proximal gastrectomy for AEG and lymph node dissection. Laparoscopic-assisted proximal gastrectomy is safe for early proximal gastric cancer and has a long-term survival outcome not inferior to total gastrectomy, but the surgical indications must be strictly selected. Abdominal lymph node metastasis of AEG is mainly in group 1, 2, 3, and 7, and mediastinal lymph node metastasis is closely related to the length of the infiltrated esophagus. The abdominal transhiatal (TH) approach can obtain a sufficient number of harvested lymph node, and has good safety and efficacy, which is the first-choice of surgical approach for early AEG. The results of the CLASS-10 clinical trial can provide a higher level of evidence for laparoscopic mediastinal lymph node dissection. Laparoscopic surgery for AEG should be carried out in experienced medical center based on clinical research.

[Clinicopathological features and survival analysis of gastric cancer patients with neuroendocrine differentiation after radical resection]

Objective: To compare the clinicopathological characteristics and the prognosis of gastric adenocarcinoma patients with and without neuroendocrine differentiation (NED) after radical gastrectomy plus D2 lymph node dissection. Methods: A retrospective cohort study was performed. The inclusion criteria were as follows: (1) patients who underwent radical resection of gastric cancer plus D2 lymph node dissection and were confirmed as gastric adenocarcinoma by postoperative pathology and received immunohistochemical examination of neuroendocrine markers Syn and/or CgA; (2) patients aged 20 to 75 years with normal organ function; (3) patients who did not receive neoadjuvant chemotherapy or radiotherapy before operation; (4) patients with postoperative pathological stage I to III according to the 8th edition of tumor staging system of American Joint Committee on Cancer (AJCC); and (5) patients who completed adjuvant chemotherapy according to the postoperative pathological stage. Those who had other malignant tumors in the past 5 years and who could not be followed up according to the required rules were excluded. According to the above criteria, the clinicopathological characteristics of gastric cancer patients who underwent radical resection plus D2 lymph node dissection in Zhongshan Hospital of Fudan University from January 2010 to June 2017 were collected and compared. All patients were followed up till June 2020. The disease-free survival (DFS) and overall survival (OS) between the patients with and without NED were compared, and the effect of NED on the prognosis was corrected by Cox proportional hazards model. The propensity score matching method was used for sensitivity analysis. Results: A total of 539 patients were enrolled in this study, including 35 with NED and 504 without NED. Compared with the patients without NED, the patients with NED were older [(65.0±7.5) years vs. (54.5±11.3) years, t=-7.681, P<0.001], had higher proportion of undergoing proximal gastrectomy [22.9% (8/35) vs. 7.6% (36/504), χ(2)=10.335, P=0.006], higher proportion of intestinal-type based on Lauren classification [77.1% (27/35) vs. 42.5% (214/504), χ(2)=14.553, P<0.001], and higher proportion of pathologic stage III [65.7% (23/35) vs. 27.6% (139/504), χ(2)=25.653, P<0.001]. The 3-year DFS of patients with NED and those without NED was 48.9% (95% CI: 33.8%-70.8%) and 37.4% (95% CI: 32.9%-42.5%) respectively, and no significant difference was found (P=0.44). The 3-year OS was 56.1% (95% CI: 39.9%-79.1%) and 64.3% (95% CI: 59.3%-69.7%) respectively, and no significant difference was found as well (P=0.32). Univariate and multivariate analyses showed that NED was not an independent risk factor for DFS and OS (all P>0.05). Sensitivity analysis showed that there was no significant difference in DFS and OS between the two groups after propensity score matching. Conclusion: Compared with patients without NED, patients with NED were older at onset, had a higher proportion of proximal gastrectomy, intestinal-type, and later diagnostic stage, but the survival prognosis had no significant difference with that of patients without NED.

[Analyses of triggers for recurrent cardiac events in 38 patients with symptomatic long QT syndrome]

Objective: To evaluate the main triggers of recurrent cardiac events in patients with symptomatic congenital long QT syndrome (cLQTS). Methods: In this retrospective case analysis study, clinical characteristics were reviewed from 38 patients with recurrent cardiac events after first visit out of 66 symptomatic cLQTS patients. General clinical data such as gender, age, clinical presentation, family history and treatment were collected, auxiliary examination results such as electrocardiogram and gene detection were analyzed. LQTS-related cardiac events were defined as arrhythmogenic syncope, implantable cardioverter defibrillator (ICD) shock, inappropriate ICD shock, aborted cardiac arrest, sudden cardiac death or ventricular tachycardia. Results: A total of 38 patients with recurrent symptoms were enrolled in this study, including 30 females (79%) and 14 children (37%). The average age of onset was (15.6±14.6) years, and the recurrence time was (3.6±3.5) years. Subtype analysis showed that there were 11 cases (29%) of LQT1 (including 2 cases of jervel-Lange Nielson syndrome), 19 cases (50%) of LQT2, 5 cases (13%) of LQT3 and 3 cases (8%) of other rare subtypes (1 LQT5, 1 LQT7 and 1 LQT11) in this patient cohort. LQT1 patients experienced recurrent cardiac event due to drug withdrawal (6 (55%)), specific triggers (exercise and emotional excitement) (4 (36%)) and medication adjustment (1 (9%)). For LQT2 patients, main triggers for cardiac events were drug withdrawal (16 (84%)), specific triggers (shock, sound stimulation, waking up (6 (32%)). One patient (5%) had recurrent syncope after pregnancy. One patient (20%) had inappropriate ICD shock. For LQT3 patients, 4 (80%) patients developed syncope during resting state, and 1 (20%) developed ventricular tachycardia during exercise test. One LQT5 patients experienced syncope and ICD shock under specific triggers (emotional excitement). One LQT11 patient had repeated ICD shocks under specific inducement (fatigue). One LQT7 patient experienced inappropriate ICD shock. Left cardiac sympathetic denervation (LCSD) significantly alleviated the symptoms in 2 children with Jervell-Lange Nielson syndrome (JLNS) post ineffective β-blocker medication. Nadolol succeeded in eliminating cardiac events in one patient with LQT2 post ineffective metoprolol medication. Mexiletine significantly improved symptoms in 2 patients with LQT2 post ineffective β-blocker medication. Conclusions: Medication withdrawal is an important trigger of the recurrence of cardiac events among patients with symptomatic congenital long QT syndrome.

Arecoline suppresses RANKL-induced osteoclast differentiation in vitro and attenuates LPS-induced bone loss in vivo

BACKGROUND

Areca nut has anti-inflammatory, antiparasitic, antihypertensive, and antidepressant properties. The pathological hallmarks of inflammatory joint diseases are an increased number of osteoclasts and impaired differentiation of osteoblasts, which may disrupt the bone remodeling balance and eventually lead to bone loss.

PURPOSE

The present study assessed the effects of arecoline, the main alkaloid found in areca nut, on osteoclast and osteoblast differentiation and function.

METHOD

M-CSF/RANKL-stimulated murine bone marrow-derived macrophages (BMMs) were incubated with several concentrations of arecoline, and TRAP staining and pit formation were assessed to monitor osteoclast formation. Quantitative real-time RT-PCR and western blot analyses were used to analyze the expression of osteoclast-associated genes and signaling pathways. The effects of arecoline on bone were investigated in an in vivo mouse model of lipopolysaccharide (LPS)-induced trabecular bone loss after oral administration of arecoline. Alizarin red S staining and assays to measure ALP activity and the transcription level of osteoblast-related genes were used to evaluate the effects of arecoline on osteoblast differentiation and bone mineralization.

RESULTS

In a dose-dependent manner, arecoline at concentrations of 50-100 μM reduced both the development of TRAP-positive multinucleated osteoclasts and the formation of resorption pits in M-CSF/RANKL-stimulated BMMs. In M-CSF/RANKL-stimulated BMMs, arecoline also suppressed the expression and translocation of c-Fos and NFATcl, and osteoclast differentiated-related genes via interference with the AKT, MAPK, and NF-kB activation pathways. Femur bone loss and microcomputed tomography parameters were recovered by oral administration of arecoline in the mouse LPS-induced bone loss model. Lastly, arecoline increased ALP activity, bone mineralization, and the expression of osteoblast differentiation-related genes, such as ALP and Runx2, in MC3T3-E1 cells.

CONCLUSION

Our data suggest that arecoline may attenuate or prevent bone loss by suppressing osteoclastogenesis and promoting osteoblastogenesis. These findings provide evidence supporting arecoline's use as a potential therapeutic agent in bone-loss disorders and diseases.

[Retrospect of 2019: focus on the research progress of gastric neoplasm]

Gastric carcinoma, gastrointestinal stromal tumor and gastric neuroendocrine tumor are the most common gastric neoplasms. A series of researches in 2019 showed that the safety and efficacy of laparoscopic gastrectomy in the treatment of both early and advanced gastric cancer patients are similar to open surgeries, providing a high-level evidence-based medical basis for the promotion of laparoscopic surgery in the treatment for gastric cancer. In multidisciplinary treatment and perioperative chemoradiotherapy, major research results have also been published, and clinical researches in China are gradually gaining international recognition and attention. Although the application of targeted therapy and immunotherapy has made progress, the first-line therapy after gastric cancer surgery has not been established. In the field of gastrointestinal stromal tumors, laparoscopic surgery has gradually been recognized, and surgical treatment of patients with advanced drug resistance still has its value. In terms of gastric neuroendocrine tumors, the latest researches showed that surgical methods should be selected according to tumor characteristics, and gastric adenocarcinoma with neuroendocrine components may have a worse prognosis.

[The shift of the treatment strategy of gastrointestinal stromal tumor from the surgical perspective]

As tumors originated from mesenchymal tissue, gastrointestinal stromal tumors (GIST) has its own typical history. For the idea of treatment for GIST at different historical periods, the role and value of surgery for the treatment of GIST keep changing. Laparoscopy and endoscopy will have the role they deserved. With the understanding of pathogenesis of GIST, targeted chemotherapy will be more and more accurate and individualized. How to improve the overall therapeutic effect of GIST, especially for the patients with the high risk and drug-resistance, is the dilemma and challenges for the surgeons.

[Efficacy of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy for gastric cancer]

Objective: To evaluate the efficacy of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy for gastric cancer in preventing duodenal stump leakage. Methods: A descriptive cohort study was conducted to retrospectively collect clinical data of 211 patients with gastric adenocarcinoma who underwent laparoscopic radical gastrectomy with Roux-en-Y or Billroth Ⅱ reconstruction and reinforcement on duodenal stump using laparoscopic single purse-string suture in Zhongshan Hospital of Fudan University between January 2013 and December 2016. Of 211 patients, 136 were male and 75 were female with mean age of (57.5±11.1)(24 to 87) years. Tumors locating at gastric upper 1/3, middle 1/3 and low 1/3 were found in 62, 68 and 81 patients respectively. Eighty-three cases underwent total gastrectomy, 128 underwent distal subtotal gastrectomy, 107 underwent Roux-en-Y reconstruction and 104 underwent Billroth II reconstruction. The procedure of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy was as follows: (1) after cutting the duodenal stump to about 2.0 cm in length, use a 3-0 single-strand absorbable suture to make a muscle layer purse at a distance of 1.0 to 1.5 cm from the duodenal stump; (2) use the purse line to make a slipknot; (3) push the duodenum stump into the purse with a needle holder or grasper; (4) tighten the knot of the purse string, and then make 4 to 5 knots for reinforcement. Postoperative complications were defined and graded according to the Clavien-Dindo grading criteria, and the incidence of early complications was recorded. Clinicopathologic features and postoperative outcomes were analyzed. Results: All patients completed operations successfully. The mean time of laparoscopic single purse-string suture was (5.1±1.6) (3.6 to 10.2) minutes. Postoperative early complication occurred in 31 cases (14.7%), of whom 27 cases developed surgery-related complications (12.8%), including 7 cases (3.3%) of peritoneal infection, 6 (2.8%) of pancreatic leakage, 4 (1.9%) of wound infection, 4 (1.9%) of gastroplegia, 2 (0.9%) of peritoneal hemorrhage, 2 (0.9%) of intestinal obstruction, 2 (0.9%) of lymphatic leakage, and no duodenal stump leakage; while 4 cases (1.9%) developed internal non-surgical complication, including 3 cases (1.4%) of pulmonary infection and 1 (0.5%) of cardiovascular event. The patient with peritoneal hemorrhage was healed after re-operation and all other patients were discharged uneventfully after conservative treatment. Four cases (1.9%) developed complications beyond grade III a of Clavien-Dindo criteria. Conclusion: Reinforcement on duodenal stump using laparoscopic single purse-string suture during laparoscopic radical gastrectomy with Roux-en-Y or Billroth II reconstruction is simple and effective, and can prevent the risk of development of duodenal stump leakage.

The Simultaneous Inhibitory Effect of Niclosamide on RANKL-Induced Osteoclast Formation and Osteoblast Differentiation

The bone destruction disease including osteoporosis and rheumatoid arthritis are caused by the imbalance between osteoblastogenesis and osteoclastogenesis. Inhibition of the NF-κB pathway was responsible for decreased osteoclastogenesis. Recently many studies indicated that niclosamide, the FDA approved an antihelminth drug, inhibits prostate and breast cancer cells growth by targeting NF-κB signaling pathways. This study evaluated the effects of niclosamide on osteoclast and osteoblast differentiation and function in vitro. In RANKL-induced murine osteoclast precursor cell RAW264.7 and M-CSF/RANKL-stimulated primary murine bone marrow-derived macrophages (BMM), niclosamide dose-dependently inhibited the formation of TRAP-positive multinucleated osteoclasts and resorption pits formation between 0.5uM and 1uM. In addition, niclosamide suppressed the expression of nuclear factor of activated T cells c1 (NFATc1) and osteoclast differentiated-related genes in M-CSF/ RANKL-stimulated BMM by interference with TRAF-6, Erk1/2, JNK and NF-κB activation pathways. However, the cytotoxic effects of niclosamide obviously appeared at the effective concentrations for inhibiting osteoclastogenesis (0.5-1uM) with increase of apoptosis through caspase-3 activation in osteoblast precursor cell line, MC3T3-E1. Niclosamide also inhibited ALP activity, bone mineralization and osteoblast differentiation-related genes expression in MC3T3-E1. Therefore, our findings suggest the new standpoint that niclosamide's effects on bones must be considered before applying it in any therapeutic treatment.

Design, synthesis and SARs of novel salicylanilides as potent inhibitors of RANKL-induced osteoclastogenesis and bone resorption

Inhibiting osteoclastogenesis is a promising therapeutic target for treating osteoclast-related diseases. Herein, we synthesized a series of modified salicylanilides and their corresponding 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione and 10-phenyldibenzo[b,f][1,4]oxazepin-11(10H)-one derivatives, and investigated the effects of such compounds on RANKL-induced osteoclast formation. Among them, a salicylanilide derivative (A04) and its 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivative (B04) markedly suppressed RANKL-induced osteoclast differentiation and showed no significant cytotoxic effects at doses higher than that required to inhibit osteoclast formation. Both compounds reduced osteoclast formation and bone resorptive activity of osteoclasts in a dose-dependent manner. Further, the anti-osteoclastogenic effects of A04 and B04 may operate through reducing the RANKL-induced nuclear translocation of NFATc1. Accordingly, we present the potent anti-osteoclastogenic compounds A04 and B04 as promising candidates for further optimization as anti-resorptive agents.

Dynamics and regulation of glycolysis-tricarboxylic acid metabolism in the midgut of Spodoptera litura during metamorphosis

Significant changes usually take place in the internal metabolism of insects during metamorphosis. The glycolysis-tricarboxylic acid (glycolysis-TCA) pathway is important for energy metabolism. To elucidate its dynamics, the mRNA levels of genes involved in this pathway were examined in the midgut of Spodoptera litura during metamorphosis, and the pyruvate content was quantified. The expression patterns of these genes in response to starvation were examined, and the interaction between protein phosphatase 1 (PP1) and phosphofructokinase (PFK) was studied. The results revealed that the expression or activities of most glycolytic enzymes was down-regulated in prepupae and then recovered in some degree in pupae, and all TCA-related genes were remarkably suppressed in both the prepupae and pupae. Pyruvate was enriched in the pupal midgut. Taken together, these results suggest that insects decrease both glycolysis and TCA in prepupae to save energy and then up-regulate glycolysis but down-regulate TCA in pupae to increase the supply of intermediates for construction of new organs. The expression of all these genes were down-regulated by starvation, indicating that non-feeding during metamorphosis may be a regulator of glycolysis-TCA pathway in the midgut. Importantly, interaction between PP1 and PFK was identified and is suggested to be involved in the regulation of glycolysis.

CD146+ mesenchymal stem cells display greater therapeutic potential than CD146- cells for treating collagen-induced arthritis in mice

Background

The characteristics and therapeutic potential of subtypes of mesenchymal stem cells (MSCs) are largely unknown. In this study, CD146⁺ and CD146^– MSCs were separated from human umbilical cords, and their effects on regulatory T cells (Tregs), Th17 cells, chondrogenesis, and osteogenesis were investigated.

Methods

Flow cytometry was used to quantify IL-6 and TGF-β1 expressed on CD146⁺ and CD146^– MSCs. The therapeutic potential of both subpopulations was determined by measuring the clinical score and joint histology after intra-articular (IA) transfer of the cells into mice with collagen-induced arthritis (CIA).

Results

Compared with CD146^– MSCs, CD146⁺ MSCs expressed less IL-6 and had a significantly greater effect on chondrogenesis. After T lymphocyte activation, Th17 cells were activated when exposed to CD146^– cells but not when exposed to CD146⁺ cells both in vitro and in vivo. IA injection of CD146⁺ MSCs attenuated the progression of CIA. Immunohistochemistry showed that only HLA-A⁺ CD146⁺ cells were detected in the cartilage of CIA mice. These cells may help preserve proteoglycan expression.

Conclusions

This study suggests that CD146⁺ cells have greater potency than CD146^– cells for cartilage protection and can suppress Th17 cell activation. These data suggest a potential therapeutic application for CD146⁺ cells in treating inflammatory arthritis.

Cytotoxic Edema in Posterior Reversible Encephalopathy Syndrome: Correlation of MRI Features with Serum Albumin Levels

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome is a clinicoradiologic entity with typical MR imaging showing predominant vasogenic and occasional cytotoxic edema. It is unclear whether MR imaging correlates with levels of serum albumin. We determined potential risk factors for development of cytotoxic edema in posterior reversible encephalopathy syndrome.

MATERIALS AND METHODS

Seventy-nine cases with typical clinical symptoms and characteristic neuroradiologic findings conformed to posterior reversible encephalopathy syndrome diagnostic criteria and were included in this study. FLAIR, DWI, and ADC maps were interpreted to evaluate the severity and type of edema. MR imaging was correlated with the levels of serum albumin, and cytotoxic edema was compared with the location and severity of brain edema.

RESULTS

Pure vasogenic edema was found in 53 cases (67.09%), and vasogenic edema complicated with cytotoxic components, in 26 patients (32.91%). There was no difference in serum albumin levels between patients with cytotoxic components and those with vasogenic edema (P = .983). There was a significant difference in the edema scale scores between patients with cytotoxic edema and those with vasogenic edema (P = .006). The percentage of cytotoxic edema located in the area with higher scale scores of edema was significantly larger than that in areas with lower scale scores of edema (P = .002).

CONCLUSIONS

Serum albumin may contribute to the development of edema in PRES but is not a decisive factor for edema type. Cytotoxic edema in posterior reversible encephalopathy syndrome is probably related to regional decreased perfusion and arteriolopathy. Further work should be undertaken to discover the pathophysiologic mechanisms involved.

Novel inhibitors of RANKL-induced osteoclastogenesis: Design, synthesis, and biological evaluation of 6-(2,4-difluorophenyl)-3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-diones

A series of novel 6-(2,4-difluorophenyl)-3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivatives were synthesized and evaluated for their inhibitory effects on osteoclast activities by using TRAP-staining assay. Among the tested compounds, 3d and 3h exhibited more potent osteoclast-inhibitory activities than the lead compound NDMC503 (a ring-fused structure of NDMC101), as reported in our previous study. Both 3d and 3h exhibited two-fold increase in activity compared to NDMC503. In addition, our biological results indicated that 3d and 3h could suppress RANKL-induced osteoclastogenesis-related marker genes, such as NFATc1, c-fos, TRAP, and cathepsin K. Notably, 3d could significantly attenuate the bone-resorbing activity of osteoclasts in the pit formation assay. Thus, this study might provide a new class of lead structures that warrant further development as potential anti-resorptive agents.

Discovery of 5-(2',4'-difluorophenyl)-salicylanilides as new inhibitors of receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis

To improve the inhibitory potency of lead compound NDMC101 on RANKL-induced osteoclastogenesis, a series of new 5-(2',4'-difluorophenyl)-salicylanilide derivatives were synthesized and evaluated for osteoclast inhibition by using TRAP-staining assay. Among them, both of compounds 6d and 6i showed three-fold increase in osteoclast-inhibitory activities compared to NDMC101 at half-inhibitory concentration. Further, the mechanistic study showed that 6d and 6i could suppress RANKL-induced osteoclastogenesis-related genes, such as NFATc1, c-fos, TRAP, and cathepsin K. Their inhibitory activities were further confirmed by including specific inhibition of NF-κB and NFATc1 expression levels in nucleus. In addition, 6d and 6i also could significantly attenuate bone-resorbing activity of osteoclasts by performing pit formation assay. Thus, a new class of 5-(2',4'-difluorophenyl)-salicylanilide derivatives may be considered as essential lead structures for the further development of anti-resorptive agents.

Modified salicylanilide and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivatives as novel inhibitors of osteoclast differentiation and bone resorption

Inhibition of osteoclast formation is a potential strategy to prevent inflammatory bone resorption and to treat bone diseases. In the present work, the purpose was to discover modified salicylanilides and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-dione derivatives as potential antiosteoclastogenic agents. Their inhibitory effects on RANKL-induced osteoclastogenesis from RAW264.7 cells were evaluated by TRAP stain assay. The most potent compounds, 1d and 5d, suppressed RANKL-induced osteoclast formation and TRAP activity dose-dependently. The cytotoxicity assay on RAW264.7 cells suggested that the inhibition of osteoclastic bone resorption by these compounds did not result from their cytotoxicity. Moreover, both compounds downregulated RANKL-induced NF-κB and NFATc1 in the nucleus, suppressed the expression of osteoclastogenesis-related marker genes during osteoclastogenesis, and prevented osteoclastic bone resorption but did not impair osteoblast differentiation in MC3T3-E1. Therefore, these modified salicylanilides and 3-phenyl-2H-benzo[e][1,3]oxazine-2,4(3H)-diones could be potential lead compounds for the development of a new class of antiresorptive agents.

TACE-dependent amphiregulin release is induced by IL-1β and promotes cell invasion in fibroblast-like synoviocytes in rheumatoid arthritis

OBJECTIVES

The aims of this study were to investigate the expression of amphiregulin (AREG) and TNF-α-converting enzyme (TACE) in fibroblast-like synoviocytes from humans with RA (FLS-RA) when stimulated with proinflammatory cytokines and to explore whether AREG plays a role in RA.

METHODS

The effects of cytokines on the expression of AREG and TACE in FLS-RA were measured by quantitative RT-PCR and western blotting. Blockade of IL-1β-mediated pathways was used to verify the involvement of intracellular signal pathways in the induction of AREG and TACE. TAPI-1 and TACE short hairpin RNA (shRNA) infection were used to identify the role of TACE in IL-1β-induced AREG secretion and shedding. AREG-induced production of MMP-1 and cadherin-11 in FLS-RA were measured by ELISA or western blotting. The effect of AREG on FLS-RA invasion was examined using a Transwell invasion assay.

RESULTS

IL-1β, but not other tested cytokines, increased the expressions of AREG mRNA and protein in a dose-responsive and time-dependent manner in FLS-RA. IL-1β induced AREG expression via p38 MAPK, NF-κB, JNK and ERK1/2 signalling pathways and induced TACE expression via PI3K, p38MAPK and NF-κB signalling pathways in FLS-RA. TACE mediated AREG secretion and shedding. EGFR (ErbB1) and Her-2 (ErbB2) were expressed in FLS-RA, and AREG increased MMP-1 and cadherin-11 expression in FLS-RA. AREG promoted the FLS-RA invasion ability.

CONCLUSION

AREG and TACE expression were up-regulated by IL-1β and their activations on FLS-RA lead to the matrix degradation by inducing MMP-1 and cadherin-11 production. TACE activity is necessary for IL-1β-induced AREG release. Our results demonstrate that IL-1β-induced AREG release may be involved in the pathogenesis of RA.

Brief Report: Single-nucleotide polymorphisms in VKORC1 are risk factors for systemic lupus erythematosus in Asians

OBJECTIVE

The increased risk of thrombosis in systemic lupus erythematosus (SLE) may be partially explained by interrelated genetic pathways for thrombosis and SLE. The present study was undertaken to investigate whether 33 established and novel single-nucleotide polymorphisms (SNPs) in 20 genes involved in hemostasis pathways that have been associated with deep venous thrombosis (DVT) in the general population are risk factors for SLE among Asian subjects.

METHODS

Patients in the discovery cohort were enrolled in 1 of 2 North American SLE cohorts. Patients in the replication cohort were enrolled in 1 of 4 Asian or 2 North American cohorts. We first genotyped 263 Asian patients with SLE and 357 healthy Asian control subjects for 33 SNPs in the discovery phase, and then genotyped 5 SNPs in up to an additional 1,496 patients and 993 controls in the replication phase. Patients were compared to controls for bivariate association with minor alleles. Principal components analysis was used to control for intra-Asian ancestry in the replication cohort.

RESULTS

Two genetic variants in the gene VKORC1 were highly significant in both the discovery and replication cohorts: rs9934438 (in the discovery cohort, odds ratio [OR] 2.45, P=2×10(-9); in the replication cohort, OR 1.54, P=4×10(-6)) and rs9923231 (in the discovery cohort, OR 2.40, P=6×10(-9); in the replication cohort, OR 1.53, P=5×10(-6)). These associations were significant in the replication cohort after adjustment for intra-Asian ancestry: for rs9934438, OR 1.34, P=0.0029; for rs9923231, OR 1.34, P=0.0032.

CONCLUSION

Genetic variants in VKORC1, which are involved in vitamin K reduction and associated with DVT, correlate with SLE development in Asian subjects. These results suggest that there may be intersecting genetic pathways for the development of SLE and thrombosis.

Hand-assisted laparoscopic surgery versus the open approach in curative resection of rectal cancer

This prospective, randomized study compared the outcomes of hand-assisted laparoscopic surgery (HALS) with open surgery for the resection of rectal cancer. The main outcome measures were procedure time, blood loss, post-operative pain, time to oral intake, return of bowel function, length of hospital stay, morbidity and functional recovery. Patients in each group were similar with regard to general status, procedure types and the histopathological features of tumours. Procedure times were significantly longer with HALS versus open surgery. Analgesic requirements, surgical blood loss, time to first passing flatus, time to first oral fluids and post-operative hospital stay length were all significantly shorter in the HALS group. At a median follow-up of 16.3 months, local recurrence of tumour was not observed in either group. In this study, the HALS approach for curative resection of rectal cancer was safe and effective and may offer several potential advantages to patients in their post-operative recovery.

Ten-year cardiovascular risk in a Hong Kong population

BACKGROUND

Cardiovascular disease is a major health issue in Hong Kong. We conducted a screening program to assess the 10-year risk for the population and to assess the potential benefit of large-scale screening in Hong Kong.

METHOD

A local screening program for cardiovascular risk was carried out in a health service network with a total of 17,716 participants. Retrospective data analysis for the prevalence and distribution of the various risk factors was performed. The data were then applied to calculate the 10-year risk of each individual, according to the European Task Force coronary risk chart.

RESULTS

Of the participants, 54.2% had total cholesterol levels > 5.2 mmol/l; 28.7% had body mass index > 25 kg/m2; 18.5% were hypertensive; 15.1% were smokers; and 3.7% had diabetes mellitus. There were 35.5% of the screened population who had at least two risk factors and 10.9% had at least three risk factors. A total of 9049 individuals satisfied the criteria for the European Task Force guidelines and were selected for 10-year cardiovascular risk analysis. We calculated that 68.0% of the male population had at least 10% risk and 41.5% had at least 20% risk of developing a coronary heart event within 10 years. Among women, 48.2% of the population carried at least 10% risk and 2.8% carried at least 20% risk.

CONCLUSION

The calculated 10-year risk of the population, particularly for men, is significant. Our study demonstrated that mass screening is feasible, and has the benefit of early identification of high-risk individuals, which could be a reasonable strategy for cost-effective medicine.

The evolution of the alcohol dehydrogenase gene family by loss of introns in plants of the genus Leavenworthia (Brassicaceae)

We present results showing that several species in the plant genus Leavenworthia, in the Brassica family, have three alcohol dehydrogenase loci, unlike Arabidopsis thaliana, which has only a single classical (class P) alcohol dehydrogenase locus. Based on a portion of the sequence, the alcohol dehydrogenase loci of Leavenworthia show about 92%-93% amino acid sequence identity to that of the A. thaliana alcohol dehydrogenase. The great majority of the sequence differences from the A. thaliana Adh-coding sequence, and also between three different Leavenworthia species, are synonymous, suggesting that all are currently functional (or have been in the recent evolutionary past). The loci differ in the numbers of introns present, with one locus (Adh-3) having no introns present. RT-PCR tests detect expression of all three loci. Linkage data using variant alleles identified by single-strand conformation polymorphism analysis show that the three Leavenworthia loci are not closely linked. The results therefore suggest that the Adh-3 locus may have arisen via an mRNA intermediate but, despite loss of the introns, is expressed.

The stage I yolk sac tumor of testis in children younger than 2 years, chemotherapy or not?

Yolk sac tumor is the most frequent germ cell tumor of testis in children. For stage I yolk sac tumor of testis in children younger than 2 years, high inguinal orchiectomy alone has been the standard treatment, with a cure rate of at least 75%. Here, we compare the treatment results of receiving chemotherapy or no chemotherapy after orchiectomy, to analyze the role of chemotherapy. From February 1987 to January 1997, 22 children younger than 2 years, with stage I yolk sac tumor of testis, were included in the study. All patients had high inguinal orchiectomy without retroperitoneal lymphadenectomy. Initial diagnostic imaging studies included computed tomographic scan of abdomen, chest radiography, and long bone survey. Clinical stage I was defined as a tumor completely resected with no evidence of local regional lymph node involvement or distant metastases. Serum alpha-fetoprotein (AFP) was assessed at diagnosis. After orchiectomy, diagnosis, and staging, patients were stratified into two treatment groups, with or without chemotherapy, according to the decision of the parents. Ten children received chemotherapy consisting of cisplatin, vinblastine, and bleomycin (PVB, modified "Einhorn regimen") for 12 weeks. The remaining 12 patients were followed up according to a "wait and see" policy. Determination of AFP was performed monthly during the first postoperative year, every other month during the second year, every 3 months during the third year, every 6 months during the fourth year, and yearly until the fifth postoperative year at least. The duration of follow-up ranged from 3 months to 119 months (median, 53 months). The Kaplan-Meier plot estimated an overall survival rate of 91.6% at 7 years after diagnosis. Among the 12 patients without chemotherapy, 2 children had relapses at 4 and 6 months after diagnosis, respectively. One was cured with PVB chemotherapy. The other patient died with refractory lung metastasis, in spite of intensive multimodality salvage therapy. The Kaplan-Meier plot showed a survival rate of 80% at 7 years and a relapse-free survival rate of 81.8% at 5 years after diagnosis. All children receiving chemotherapy were alive and free from relapse. There was no significant treatment-related toxicity. Our results may suggest that PVB chemotherapy after orchiectomy is an affective and safe regimen for stage I yolk sac tumor of testis in children younger than 2 years. Instead of four courses of PVB as used here, two or three courses could be enough. To elucidate the necessity for chemotherapy and to determine the number of courses of PVB needed (if chemotherapy is given), a randomized study of more cases is warranted.

Application of anticancer agent embolism in Miles' operation

Presented in this paper is a report of the prospective studies on rectal cancer. By using the method of anticancer agent gelatin sponge to form embolism and by ligating the bilateral arteria iliaca internal, we performed Miles' operation on 64 cases of rectal cancer. Only 24 cases in the control group had Miles' operation. The amount of blood transfused during operation, duration of operation, days of hospitalization, infection rate of incision on the peritoneum, and relapse rate in treated group were significantly different from those in the control group (P < 0.05).

Assessment of autopsic samples of carotid atherosclerosis in the aged by intravascular ultrasound

To assess the value of intravascular ultrasound in detecting carotid atherosclerosis, we compared the ultrasound images of 48 carotid artery segments from autopsies with their histological findings. The results showed that by intravascular ultrasonography one could distinguish between elastic and muscular tissues of arteries, determine the lesions of fibroelastosis and calcified plaques on arterial wall, and precisely measure the wall thickness, inner and outer diameter, luminal area and cross-sectional area of arteries with a high correlation between the data measured from ultrasonography and histological study (r values were 0.98, 0.97, 0.97, 0.96 and 0.96, respectively). This study suggests that intravascular ultrasound might be effectively used for morphological study and detection of atherosclerotic lesions in vivo.

Kinetics of the clonal proliferation of granulocytes and macrophages in cultures of mouse bone marrow cells as supported by two distinct types of colony-stimulating factors

Two different types of colony-stimulating factors (CSF) were used to support the clonal growth of myeloid progenitor cells (CFUc) in semi-solid agar or viscous methylcellulose cultures of mouse bone marrow cells. The cultures stimulated for 5 days with RSP-2-P3 cell CSF (CSFRSP) contained mainly granulocyte colonies, whereas the cultures stimulated for 10 days with human urine CSF (CSFhu) contained mainly monocyte/macrophage colonies. Four lines of study were carried out: 1) a kinetic study using combinations of the two types of CSFs in the same culture; 2) a study of transferring CFUc from the initial 3-day cultures to recipient cultures containing the same or different types of CSF; 3) an examination of the morphology over time of colonies that were confined by glass capillaries plunged in agar; and 4) electron microscopic observations on disintegrating granulocytes. The results of all these lines of study suggest that about one third of the CFUc can be stimulated both by CSFRSP and CSFhu while the other two thirds react specifically either with CSFRSP or with CSFhu. The present study also suggests that granulocytes in the culture stop proliferation and disintegrate while macrophages are still growing there. Thus, mixed-type colonies containing both macrophages and granulocytes later become macrophage colonies.

Range of accuracy of two wavelength oximetry

Earlier reports of a two wavelength oximeter suggested a tendency toward overestimation of arterial oxygen saturation (SaO2) at the lowest values examined. To investigate this possible inaccuracy, we compared oximeter readings to SaO2 over a wider range of laboratory-induced steady-state hypoxia than has previously been reported. For values of SaO2 greater than 75 percent, oximeter readings were linearly related to SaO2 such that y = 0.94 SaO2 + 8.7 (r = 0.96) and the mean difference between oximeter reading and SaO2 was 0.09 percent. However, when SaO2 was less than 75 percent, the instrument readings were progressively higher than the SaO2 so that when SaO2 was approximately 50 percent, the oximeter reading was approximately 65 percent. These data show that the two wavelength oximeter displays falsely elevated readings when the arterial saturation falls below 75 percent.

Influence of supplemental oxygen on the physiological response to the PO2 aerobic exerciser

Acute physiological responses to the "PO2-Aerobic Exerciser" (AE), a partial rebreathing device designed to stimulate training at altitudes, were studied in seven healthy men [mean VO2max = 56.1 +@- 10.1 (SD) ml X kg-1 X min-1] who performed cycle ergometer exercise to exhaustion in three experimental situations: a control test (C) breathing normal atmosphere: a test with the device (AE); and a test with the AE air supplemented with oxygen (AEO2'). Arterial oxygen saturation at rest for C, AE, and AEO2' studies was 97 +/- 1, 95 +/- 2, and 97 +/- 1%, respectively (P less than 0.05 for C vs AE and AE vs AEO2'), while at exhaustion it was 95 +/- 1, 87 +/- 2, and 95 +/- 1%, respectively (P less than 0.05 for C vs AE and AE vs AEO2'). Maximum work rate decreased from a control value of 1738 +/- 184 kg X min-1 to 1371 +/- 147 kg X min-1 during AE and remained below control levels during AEO2'; 1554 +/- 110 kg X min-1 (P less than 0.05). Beyond 60% of maximum work rate during AE, inspired CO2 increased to 0.026 +/- 0.005. Mouth pressure swings of up to -19.2 +/- 10.2 and 12.7 +/- 5.7 cm H2O were recorded during AE. While the PO2 aerobic exerciser induced a hypoxic stress, the pertubation imposed was not explained fully by arterial oxygen desaturation. Other factors such as hypercapnia and a flow resistive increase in the work of breathing appear to have influenced work capacity during the use of the device.

Conjunctival oxygen tension and its relationship to arterial oxygen tension

Using a miniaturized Clark electrode embedded in a polymethylmethacrylate eyepiece, we measured transconjunctival oxygen tension (PcjO2) in 5 healthy volunteer subjects at multiple levels of steady-state isocapnic hypoxia, normoxia, and hyperoxia. PcjO2 was linearly related to arterial oxygen tension (PaO2) as PaO2 ranged from 28 to 205 mm Hg (PcjO2 = 0.59 PaO2 + 0.36 mm Hg; r = 0.94; standard error of the estimate = 7.09 mm Hg). However, the relationships between PcjO2 and PaO2 varied significantly among subjects. Whereas the overall mean ratio of PcjO2 to PaO2 was 0.59, the mean ratio for subjects ranged from 0.47 to 0.79 and was significantly different among subjects (P less than 0.0001). The time response of the electrode to a step change in oxygen tension in vitro was exponential, with a 90% response time of 38 seconds after a lag of 3.7 seconds. The time responses to in vivo changes in oxygen tension were also exponential. From hypoxia to normoxia, 90% response time was 45.0 seconds after a lag of 5.1 seconds; from room air to hypoxia, 90% response time was 72.4 seconds after a lag of 30.3 seconds; from room air to hyperoxia, 90% response time was 87.2 seconds after a lag of 6.8 seconds. We conclude that, although PcjO2 measured by a miniaturized Clark electrode is linearly related to PaO2 in healthy subjects, variation in the relationship of PcjO2 to PaO2 among individuals will prevent precise estimation of PaO2 for any individual unless subject-specific calibration is performed.

Amiodarone pulmonary toxicity: functional and ultrastructural evaluation

Pulmonary function, chest radiographic appearances, and the cellular composition of bronchoalveolar lavage fluid were assessed in 13 patients who were receiving amiodarone treatment. Eight of the patients had developed clinical and radiological evidence of lung disease and five were symptom free. The proportions of lymphocytes (mean 8.6 (SD 6.9)) and neutrophils (mean 3.4 (3.3)) obtained by bronchoalveolar lavage were similar in patients with and without lung complications. Electron microscopic examination of alveolar macrophages showed intralysosomal inclusion bodies in all subjects, regardless of clinical state. There was no significant difference in the mean number of inclusion bodies per macrophage transection between those with and those without lung disease. The differential cell count in bronchoalveolar lavage fluid and the presence of macrophage inclusion bodies were therefore not useful as markers of disease activity. Among those who developed clinical and radiological evidence of lung disease, the cumulative drug dose per kilogram of body weight and the duration of treatment (mean 16.5 (SD 9.0) months) were significantly correlated with the degree of lung restriction as measured by total lung capacity and forced vital capacity. It is concluded that, while the severity of the restrictive pulmonary defect that is induced by amiodarone is largely dose related, the development of lung toxicity is to some extent idiosyncratic.