Percutaneous antegrade management of large proximal ureteral stones using non-papillary puncture

Objective:To evaluate the feasibility and the safety of medial non-papillary percutaneous nephrolithotomy(npPCNL)for the management of large proximal ureteral stones.Methods:We evaluated prospectively collected data of 37 patients with large proximal ureteral stones more than 1.5 cm in diameter treated by prone npPCNL.Depending on stone size,in-toto stone removal or lithotripsy using the Lithoclast®Trilogy(EMS Medical,Nyon,Switzerland)was performed.Perioperative parameters including operative time(from start of puncture to the skin suturing),stone extraction time(from the first insertion of the nephroscope to the extraction of all stone fragments),and the stone-free rate were evaluated.Results:Twenty-one males and 16 females underwent npPCNL for the management of large upper ureteral calculi.The median age and stone size of treated patients were 58(interquartile range[IQR]:51-69)years and 19.3(IQR:18.0-22.0)mm,respectively.The median operative time and stone extraction time were 25(IQR:21-29)min and 8(IQR:7-10)min,respectively.One case(2.7%)of postoperative bleeding and two cases(5.4%)of prolonged fever were managed conservatively.The stone-free rate at a 1-month follow-up was 94.6%.Conclusion:The npPCNL provides a straight route to the ureteropelvic junction and proximal ureter.Approaching from a dilated portion of the ureter under low irrigation pressure with larger diameter instruments results in effective and safe stone extraction within a few minutes.

L_(1)-Smooth SVM with Distributed Adaptive Proximal Stochastic Gradient Descent with Momentum for Fast Brain Tumor Detection

Brain tumors come in various types,each with distinct characteristics and treatment approaches,making manual detection a time-consuming and potentially ambiguous process.Brain tumor detection is a valuable tool for gaining a deeper understanding of tumors and improving treatment outcomes.Machine learning models have become key players in automating brain tumor detection.Gradient descent methods are the mainstream algorithms for solving machine learning models.In this paper,we propose a novel distributed proximal stochastic gradient descent approach to solve the L_(1)-Smooth Support Vector Machine(SVM)classifier for brain tumor detection.Firstly,the smooth hinge loss is introduced to be used as the loss function of SVM.It avoids the issue of nondifferentiability at the zero point encountered by the traditional hinge loss function during gradient descent optimization.Secondly,the L_(1) regularization method is employed to sparsify features and enhance the robustness of the model.Finally,adaptive proximal stochastic gradient descent(PGD)with momentum,and distributed adaptive PGDwithmomentum(DPGD)are proposed and applied to the L_(1)-Smooth SVM.Distributed computing is crucial in large-scale data analysis,with its value manifested in extending algorithms to distributed clusters,thus enabling more efficient processing ofmassive amounts of data.The DPGD algorithm leverages Spark,enabling full utilization of the computer’s multi-core resources.Due to its sparsity induced by L_(1) regularization on parameters,it exhibits significantly accelerated convergence speed.From the perspective of loss reduction,DPGD converges faster than PGD.The experimental results show that adaptive PGD withmomentumand its variants have achieved cutting-edge accuracy and efficiency in brain tumor detection.Frompre-trained models,both the PGD andDPGD outperform other models,boasting an accuracy of 95.21%.

Clinical efficacy of modified Kamikawa anastomosis in patients with laparoscopic proximal gastrectomy

BACKGROUND With the increasing incidence of proximal gastric cancer,laparoscopic proximal gastrectomy has been applied.However,reflux esophagitis often occurs after traditional esophagogastric anastomosis.In order to solve this problem,several methods of digestive tract reconstruction have emerged,but the most satisfying method remains to be discussed.Therefore,we modified traditional Kamikawa anastomosis to investigate the appropriate digestive tract reconstruction in laparo-scopic proximal gastrectomy.All the patients were successfully operated on without conversion to laparotomy.The duration of operation and digestive tract reconstruction were 203.500(150-224)min and 87.500(73-111)min,respectively.The intraoperative amount of bleeding was 20.500 mL±0.696 mL.The time of postoperative first flatus,the first postoperative fluid intake,and the postoperative length of stay were 2(1-3)d,4(3-5)d,and 9(8-10)d,respectively.All the patients were followed up for 12-23 months.The body mass index at 6 and 12 months after surgery were 22.577 kg/m2±3.098 kg/m2 and 22.594 kg/m2±3.207 kg/m2,respectively.The nutrition risk screening 2002 score,the patient-generated subjective global assessment score,and the gastroesophageal reflux disease scale score were good at 6 and 12 months after surgery.Reflux esophagitis and anastomotic stenosis were not observed in any of the patients during their 12-month postoperative gastroscopy or upper gastrointestinal tract visits.All the patients exhibited no tumor recurrence or metastasis.CONCLUSION The modified Kamikawa anastomosis is safe and feasible for laparoscopic proximal gastrectomy and has good antireflux effects and nutritional status.

Watson-Jones Anatomical Approach for Open Reduction and Internal Fixation of Proximal Femoral Fractures without Image Intensifier in a Low-Resource Setting

Introduction: Standard procedures for surgical fixation of proximal femoral fractures (PFF) require an image intensifier which in developing countries remains a luxury. We hypothesized that, with a well-codified technique, the Watson Jones approach (WJA) without image intensifier nor traction table, can allow open reduction and internal fixation (ORIF) of PFF using Dynamic hip screw (DHS), with satisfactory outcome. Patients and methods: Forty one consecutive patients (mean age 59.5 ± 21.6 years, 61% males) who were followed in a Teaching Hospital for PFF treated by ORIF using the WJA and DHS from January 2016 to December 2020 were reassessed. The outcome measures were the quality of the reduction, the positioning of the implants, the tip-apex distance (TAD), the rate and delay of consolidation, the functional results using Postel Merle d’Aubigné (PMA) score, the rate of surgical site infection (SSI) and the overall mortality. Logistic regression was used to determine factors associated with mechanical failure. Results: The mean follow-up period was 33.8 ± 15.0 months. Fracture reduction was good in 31 (75.6%) cases and acceptable in 8(19.5%) cases. Implant position was fair to good in 37 (90.2%) patients. The mean TAD was 26.1 ± 3.9 mm. Three patients developed SSI. Consolidation was achieved in 38 (92.6%) patients. The functional results were good to excellent in 80.5% of patients. The overall mortality rate was 7.3%. There were an association between mechanical failure and osteoporosis (p = 0.04), fracture reduction (p = 0.003), and TAD (p = 0.025). In multivariate logistic regression, no independent factors were predictive of mechanical failure. Conclusion: This study shows that ORIF using DHS for PFF via the Watson-Jones approach without an image intensifier can give satisfactory anatomical and functional outcomes in low-resource settings. It provides and validates a reliable and reproducible technique that deserves to be diffused to surgeons in austere areas over the world.

Almost Sure Convergence of Proximal Stochastic Accelerated Gradient Methods

Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stochastic proximal gradient method performs well. However, research on its accelerated version remains unclear. This paper proposes a proximal stochastic accelerated gradient (PSAG) method to address problems involving a combination of smooth and non-smooth components, where the smooth part corresponds to the average of multiple block sums. Simultaneously, most of convergence analyses hold in expectation. To this end, under some mind conditions, we present an almost sure convergence of unbiased gradient estimation in the non-smooth setting. Moreover, we establish that the minimum of the squared gradient mapping norm arbitrarily converges to zero with probability one.

Feldman-Katok度量下Li-Yorke混沌和Proximal对

通过Feldman-Katok引入了FK Li-Yorke混沌和FK Proximal对,并且研究它们之间的关系.证明如果一个拓扑动力系统是FK敏感的,并且含有一个由传递点和周期点组成的FK Proximal对,则它是FK Li-Yorke混沌的.

Double-tract reconstruction is superior to esophagogastrostomy in controlling reflux esophagitis and enhancing quality of life after proximal gastrectomy:Results from a prospective randomized controlled clinical trial in China

Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),nutritional status and surgical safety.Methods:This study was a randomized controlled trial.Patients eligible for PG were enrolled and randomly assigned to the EG group and DTR group.The characteristics of patients,parameters for surgical safety,incidence of reflux esophagitis,nutrition status and QOL were collected and compared between the two groups.Univariate analysis and multivariate analysis were performed to determine the significant factors affecting the incidence of reflux esophagitis after PG.Results:Thirty-seven patients of the EG group and 36 patients of the DTR group were enrolled.The incidence of reflux esophagitis was significantly lower in the DTR group than in the EG group(8.3%vs.32.4%,P=0.019).The DTR group demonstrated a more favorable QOL than the EG group after PG.The nutritional status was balanced within the EG group and the DTR group.The operation time was longer in the DTR group than in the EG group(191 min vs.221 min,P=0.001),while surgical safety was similar in the two groups.Conclusions:Our research demonstrated that DTR is superior to EG after PG in terms of the incidence of reflux esophagitis and provides a more satisfactory QOL without increasing surgical complications or sacrificing nutritional status.

Anti-reflux effects of a novel esophagogastric asymmetric anastomosis technique after laparoscopic proximal gastrectomy

BACKGROUND Reflux esophagitis is a common postoperative complication of proximal gastrectomy.There is an urgent need for a safer method of performing esophageal-gastric anastomosis that reduces the risk of reflux after proximal gastrectomy.We hypothesize that a novel technique termed esophagogastric asymmetric anastomosis(EGAA)can prevent postoperative reflux in a safe and feasible manner.To observe a novel method of EGAA to prevent postoperative reflux.METHODS Initially,we employed a thermal stress computer to simulate and analyze gastric peristalsis at the site of an esophagogastric asymmetric anastomosis.This was done in order to better understand the anti-reflux function and mechanism.Next,we performed digestive tract reconstruction using the EGAA technique in 13 patients who had undergone laparoscopic proximal gastrectomy.Post-surgery,we monitored the structure and function of the reconstruction through imaging exams and gastroscopy.Finally,the patients were followed up to assess the efficacy of the anti-reflux effects.RESULTS Our simulation experiments have demonstrated that the clockwise contraction caused by gastric peristalsis and the expansion of the gastric fundus caused by the increase of intragastric pressure could significantly tighten the anastomotic stoma,providing a means to prevent the reverse flow of gastric fluids.Thirteen patients with esophagogastric junction tumors underwent laparoscopic proximal gastrectomy,with a mean operation time of 304.2±44.3 min.After the operation,the upper gastroenterography in supine/low head positions showed that eight patients exhibited no gastroesophageal reflux,three had mild reflux,and two had obvious reflux.The abdominal computed tomography examination showed a valve-like structure at the anastomosis.During followup,gastroscopy revealed a closed valve-like form at the anastomosis site without stenosis or signs of reflux esophagitis in 11 patients.Only two patients showed gastroesophageal reflux symptoms and mild reflux esophagitis and were treated with proton pump inhibitor therapy.CONCLUSION EGAA is a feasible and safe surgical method,with an excellent anti-reflux effect after proximal gastrectomy.

Treatment of proximal humeral fractures accompanied by medial calcar fractures using fibular autografts:A retrospective,comparative cohort study

BACKGROUND Severe proximal humerus comminuted fractures are often accompanied by medial calcar comminuted fractures and loss of medial support,which are important factors that lead to internal fixation failure.The appropriate treatment for proximal humerus comminuted fractures has not been established.Therefore,this study assessed the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.AIM To investigate the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.METHODS This retrospective,comparative cohort study included two groups of patients.Group 1 comprised 22 patients and group 2 comprised 25 patients with complete follow-up data.Group 1 was treated with a fibular autograft with open reduction and locking plates to enable internal fixation.Group 2 was treated with open reduction and locking plates to enable internal fixation.The intraoperative blood loss volume from the shoulder wound,operative time,shoulder wound pain,bone fracture healing time,Constant-Murley score of the shoulder joint,preoperative Holden walking function score,Mallet score of the shoulder joint,and humeral neck-shaft angle during surgery of the two groups were compared,and the differences were analysed using an independent sample t-test.RESULTS Group 1 had a shorter mean operative time than group 2(2.25±0.30 h vs 2.76±0.44 h;P=0.000).Group 1 had a lower shoulder wound pain score on the first day after surgery than group 2(7.91±1.15 points vs 8.56±1.00 points;P=0.044).Group 1 had a shorter fracture healing time than group 2(2.68±0.48 mo vs 3.64±0.64 mo;P=0.000).Group 1 had higher Constant-Murley scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(76.64±4.02 points vs 72.72±3.02 points,86.36±3.53 points vs 82.96±3.40 points,and 87.95±2.77 points vs 84.68±2.63 points,respectively;P=0.000,0.002,and 0.000,respectively).Group 1 had higher Mallet scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(10.32±0.57 points vs 9.96±0.54 points,13.36±1.00 points vs 12.60±0.87 points,and 13.91±0.75 points vs 13.36±0.70 points,respectively;P=0.032,0.007,and 0.013,respectively).CONCLUSION Using locking plates with a fibular autograft can recreate medial support,facilitate fracture healing,and improve shoulder function;therefore,this may be an effective treatment option for severe proximal humerus comminuted fractures.

Esophagogastric Reconstruction in Cobra-Head Shape with Toupet-Like Partial Anti-Reflux Technique for Resection of Proximal Gastric Tumors. Experience with Three Cases from a Non-Asian Population

Background: Proximal gastrectomy is a rarely performed procedure but a feasible option in benign tumors and malignant neoplasms in the proximal third of the stomach since novel options of reconstructions are available nowadays with fewer long-term sequels. Methods: Report of three cases of proximal gastric gastrointestinal stromal tumors (GIST), with a description of its presentation, histological characteristics, and follow-up after being treated with proximal gastrectomy with cobra head reconstruction. Results: Case 1: A 62-year-old woman with epigastric pain of four months with endoscopic evidence of a cardia GIST. The surgery was performed without complications. The histopathological report confirmed a fusiform GIST of 3.2 × 3 × 2.5 cm, stage IA. No adjuvant treatment was considered. An esophagogram showed no evidence of reflux and no stenosis, and no disease recurrence after 40-months follow-up. Case 2: A 66-year-old woman with dyspepsia and a palpable tumor in the epigastrium. The surgery was performed without complications. The pathology report confirmed a proximal gastric GIST of 13 × 8 × 7 cm, staged II. She received adjuvant treatment with imatinib for 36 months without recurrence and no reflux or stenosis. Case 3: A 55-year-old woman with intermittent hematemesis and right subscapular pain. The surgery was performed without complications. The histopathological report concluded that a GIST tumor of the cardia, 1.4 × 1.2 cm, staged IA. She was left in observation. At a 6-month follow-up, she does not report dysphagia, reflux, or stenosis, and no locoregional recurrence. Conclusions: Open and laparoscopic proximal gastrectomy is a safe therapeutic option for GIST. Furthermore, the reconstruction of the esophagus-gastro anastomosis in the cobra head after proximal gastrectomy is feasible and secure in our population, with good functional results in a short follow-up.

多目标优化问题proximal真有效解的最优性条件

在广义凸性假设下,给出了集合proximal真有效点的线性标量化,并在此基础上证明了它与Benson真有效点和Borwein真有效点的等价性.将这些结果应用到多目标优化问题上,得到proximal真有效解的最优性条件.最后,利用proximal次微分,得到了proximal真有效解的模糊型最优性条件.

Proximal gastrectomy with jejunal interposition and TGRY anastomosis for proximal gastric cancer

AIM: To compare the short-term outcomes of patients who underwent proximal gastrectomy with jejunal interposition(PGJI) with those undergoing total gastrectomy with Roux-en-Y anastomosis(TGRY).METHODS: From January 2009 to January 2011, thirty-five patients underwent PGJI, and forty-one patients underwent TGRY. The surgical efficacy and short-term follow-up outcomes were compared between the two groups.RESULTS: There were no differences in the demographic and clinicopathological characteristics. The mean operation duration and postoperative hospital stay in the PGJI group were statistically longer than those in the TGRY group(P = 0.00). No anastomosis leakage was observed in two groups. No statistically significant difference was found in endoscopic findings, Visick grade or serum albumin level. The single-meal food intake in the PGJI group was more than that in the TGRY group(P = 0.00). The PG group showed significantly better hemoglobin levels in the second year(P = 0.02). The twoyear survival rate was not significantly different(PGJI vsTGRY, 93.55% vs 92.5%, P = 1.0).CONCLUSION: PGJI is a safe, radical surgical method for proximal gastric cancer and leads to better outcomes in terms of the single-meal food intake and hemoglobin level, compared with TGRY in the short term.

Does proximal femoral nail antirotation achieve better outcome than previous-generation proximal femoral nail?

BACKGROUND There are few studies in the literature comparing the clinical outcomes and radiographic results of proximal femoral nail(PFN)and proximal femoral nail antirotation(PFNA)for pertrochanteric femoral fracture(PFF)in elderly patients.AIM To evaluate both clinical and radiographic outcomes after fixation with PFN and PFNA in an elderly patient population.METHODS One hundred fifty-eight patients older than 65 years with PFF who underwent fixation with either PFN or PFNA were included.Seventy-three patients underwent fixation with PFN,whereas 85 were fixed with PFNA.The mean follow-up was 2.4 years(range,1-7 years).Clinical outcome was measured in terms of operation time,postoperative function at each follow-up visit,and mortality within one year.Radiographic evaluation included reduction quality after surgery,Cleveland Index,tip-apex distance(TAD),union rate,time to union,and sliding distance of the screw or blade.Complications including nonunion,screw cutout,infection,osteonecrosis of the femoral head,and implant breakage were also investigated.RESULTS Postoperative function was more satisfactory in patients who underwent PFNA than in those who underwent PFN(P=0.033).Radiologically,the sliding difference was greater in PFN than in PFNA patients(6.1 and 3.2 mm,respectively,P=0.036).The rate of screw cutout was higher in the PFN group;eight for PFN(11.0%)and two for PFNA patients(2.4%,P=0.027).There were no differences between the two groups in terms of operation time,mortality rate at one year after the operation,adequacy of reduction,Cleveland Index,TAD,union rate,time to union,nonunion,infection,osteonecrosis,or implant breakage.CONCLUSION Elderly patients with PFF who underwent PFNA using a helical blade demonstrated better clinical and radiographic outcomes as measured by clinical score and sliding distance compared with patients who underwent PFN.

Treatment of Pathological Fractures of the Proximal Femur Due to Advanced Metastasis of Highly Malignant Tumors: A Clinical Controlled Study of Enterostenosis Reconstruction and Conservative Treatment

Objective: To investigate whether different treatment methods have an impact on the quality of life and life span after fracture of patients with proximal femoral pathological fractures caused by advanced metastasis of highly malignant tumors. Methods: Karnofsky performance status (KPS) and visual analogue score (VAS) were counted at the time of admission and 2 months after the treatments. Survival analysis was implemented to compare the median survival time and 6-month survival rate of the 2 groups. Musculoskeletal score (MSTS) was used to evaluate limb function in the surgical group at 2 months after the treatment. Results: There was no significant difference in KPS score and VAS score between the two groups at the time of admission (p > 0.05). At 2 months after treatment, the KPS score of the surgical group was higher than that of the conservative group (P < 0.05), and the VAS score of the survivors of the surgical group was lower than that of the conservative group (P < 0.05). Survival analysis showed that the median survival time and 6-month survival rate after fracture in the surgical group were higher than those in the conservative group (P < 0.05). After 2 months of treatment, the average MTST score of survivors in the surgical group was 20.38 ± 0.9 (16 - 26 points). Conclusion: Surgical intervention can benefit patients with pathological fractures of the proximal femur due to metastasis of highly malignant tumors in terms of quality of life and survival. Local tumor resection and endoparasitic replacement, which can be tolerated by most patients, can effectively reconstruct the limb function of these patients and restore their self-care ability.

Laparoscopic splenic hilum lymph node dissection for advanced proximal gastric cancer:A modified approach for pancreasand spleen-preserving total gastrectomy

AIM:To investigate the feasibility and optimal approach for laparoscopic pancreasand spleen-preserving splenic hilum lymph node dissection in advanced proximal gastric cancer.METHODS:Between August 2009 and August 2012,12 patients with advanced proximal gastric cancer treated in Nanfang Hospital,Southern Medical University,Guangzhou,China were enrolled and subsequently underwent laparoscopic total gastrectomy with pancreasand spleen-preserving splenic hilum lymph node(LN)dissection.The clinicopathological characteristics,surgical outcomes,postoperative course and followup data of these patients were retrospectively collected and analyzed in the study.RESULTS:Based on our anatomical understanding of peripancreatic structures,we combined the characteristics of laparoscopic surgery and developed a modified approach(combined supraand infra-pancreatic approaches)for laparoscopic pancreasand spleenpreserving splenic hilum LN dissection.Surgery was completed in all 12 patients laparoscopically without conversion.Only one patient experienced intraoperative bleeding when dissecting LNs along the splenic artery and was handled with laparoscopic hemostasis.The mean operating time was 268.4 min and mean number of retrieved splenic hilum LNs was 4.8.One patient had splenic hilum LN metastasis(8.3%).Neither postoperative morbidity nor mortality was observed.Peritoneal metastasis occurred in one patient and none of the other patients died or experienced recurrent disease during the follow-up period.CONCLUSION:Laparoscopic total gastrectomy with pancreasand spleen-preserving splenic hilum LN dissection using the modified approach for advanced proximal gastric cancer could be safely achieved.

Management of proximal humerus fractures in adults

The majority of proximal humerus fractures are lowenergy osteoporotic injuries in the elderly and their incidence is increasing in the light of an ageing population. The diversity of fracture patterns encountered renders objective classification of prognostic value challenging. Non-operative management has been associated with good functional outcomes in stable, minimally displaced and certain types of displaced fractures.Absolute indications for surgery are infrequent and comprise compound, pathological, multi-fragmentary head-splitting fractures and fracture dislocations, as well as those associated with neurovascular injury. A constantly expanding range of reconstructive and replacement options however has been extending the indications for surgical management of complex proximal humerus fractures. As a result, management decisions are becoming increasingly complicated, in an attempt to provide the best possible treatment for each indi-vidual patient, that will successfully address their specific fracture configuration, comorbidities and functional expectations. Our aim was to review the management options available for the full range of proximal humerus fractures in adults, along with their specific advantages, disadvantages and outcomes.

Retrospective evaluation of lymphatic and blood vessel invasion and Borrmann types in advanced proximal gastric cancer

BACKGROUND The Borrmann classification system is used to describe the macroscopic appearance of advanced gastric cancer,and Borrmann typeⅣdisease is independently associated with a poor prognosis.AIM To evaluate the prognostic significance of lymphatic and/or blood vessel invasion(LBVI)combined with the Borrmann type in advanced proximal gastric cancer(APGC).METHODS The clinicopathological and survival data of 440 patients with APGC who underwent curative surgery between 2005 and 2012 were retrospectively analyzed.RESULTS In these 440 patients,LBVI+status was associated with Borrmann typeⅣ,low histological grade,large tumor size,and advanced pT and pN status.The 5-year survival rate of LBVI+patients was significantly lower than that of LBVI– patients,although LBVI was not an independent prognostic factor in the multivariate analysis.No significant difference in the prognosis of patients with Borrmann typeⅢ/LBVI+disease and patients with Borrmann typeⅣdisease was observed.Therefore,we proposed a revised Borrmann typeⅣ(r-BorⅣ)as Borrmann typeⅢplus LBVI+,and found that r-BorⅣwas associated with poor prognosis in patients with APGC,which outweighed the prognostic significance of pT status.CONCLUSION LBVI is related to the prognosis of APGC,but is not an independent prognostic factor.LBVI status can be used to differentiate Borrmann typesⅢandⅣ,and the same approach can be used to treat r-BorⅣand Borrmann typeⅣ.

Protective Effects of Quercetin on Cadmium-induced Cytotoxicity in Primary Cultures of Rat Proximal Tubular Cells

Objective To investigate the protective effects of quercetin on cadmium-induced cytotoxicity in primary cultures of rat proximal tubular （rPT） cells. Methods Primary cultures of rPT cells undergoing exponential growth were incubated with 1.0 ug/mL quercetin and/or cadmium （2.5, 5.0 umol/L）, in a serum-free medium at 37℃ at different time intervals. Commercial kits were used and flow cytometric analyses were performed on rPT cell cultures to assay apoptosis and oxidative stress. Results Exposure of rPT cells to cadmium acetate （2.5, 5.0 umol/L） induced a decrease in cell viability, caused an increase in apoptotic rate and apoptotic morphological changes. Simultaneously, elevation of intracellular reactive oxygen species, malondialdehyde and calcium levels, depletion of mitochondrial membrane potential and intracellular glutathione, and inhibition of Na＋, K＋ -ATPase, Ca2＋ -ATPase, glutathione peroxidase （GSH-Px）, catalase （CAT）, and superoxide dismutase （SOD） activities were revealed during the cadmium exposure of rPT cells. However, simultaneous supplementation with 1 ug/mL quercetin protected rPT cells against cadmium-induced cytotoxicity through inhibiting apoptosis, attenuating lipid peroxidation, renewing mitochondrial function and elevating the intracellular antioxidants （non-enzymatic and enzymic） levels. Conclusion The present study has suggested that quercetin, as a widely distributed dietary antioxidant, contributes potentially to prevent cadmium-induced cytotoxicity in rPT cells.

Clinical importance and surgical decision-making regarding proximal resection margin for gastric cancer

Because of the intramural spread of gastric cancer,a sufficient length of a resection margin has to be attained to ensure complete excision of the tumor.There has been debate on an adequate length of proximal resection margin(PRM) and its related issues.Thus,the objective of this article is to review several studies on PRM and to summarize the current evidence on the subject.Although there is some discrepancy in the recommended values for PRM between authors,a PRM of more than 2-3 cm for early gastric cancer and 5-6 cm for advanced gastric cancer is thought to be acceptable.Once the margin is confirmed to be clear,however,the length of PRM measured in postoperative pathologic examination does not affect the patient's survival,even when it is shorter than the recommended values.Hence,the recommendations for PRM length should be applied only to intraoperative decision-making to prevent positive margins on the final pathology.Given that a negative resection margin is the ultimate goal of determining an adequate PRM,development and improvement of reliable methods to confirm a negative resection margin intraoperatively would minimize the extent of surgery and offer a better quality of life to more patients.In the same context,special attention has to be paid to patients who have advanced stage or diffuse-type gastric cancer,because they are more likely to have a positive margin.Therefore,a wider excision with intraoperative frozen section(IFS) examination of the resection margin is necessary.Despite all the attempts to avoid positive margins,there is still a certain rate of positive-margin cases.Since the negative impact of a positive margin on prognosis is mostly obvious in low N stage patients,aggressive further management,such as extensive re-operation,is required for these patients.In conclusion,every possible preoperative and intraoperative evaluation should be thoroughly carried out to identify in advance the patients with a high risk of having positive margins;these patients need careful management with a wider excision or an IFS examination to confirm a negative margin during surgery.

Assessment of proximal gastric accommodation in patients with functional dyspepsia

Impaired gastric accommodation is one of the most important etiologic factors in the pathophysiology of functional dyspepsia.Ultrasound is a potential alternative method to study changes in gastric volume as a reflection of gastric accommodation.Ultrasound is suitable for patients because it is a non-invasive,easily repeated and non-radioactive procedure,and a previous study has demonstrated the feasibility of 3-dimensional ultrasound in examining functional dyspepsia.The brief article by Fan et al demonstrated that both the proximal gastric area and volume,measured by 2-and 3-dimensional ultrasound respectively,were significantly smaller in patients with functional dyspepsia than in healthy controls.These results are very interesting,but we raise the relevant point that it should have been mandatory to study both changes in gastric volume and their relationship with upper gastrointestinal symptoms in functional dyspepsia.In fact,the relationship between cardinal symptoms and several pathophysiologic mechanisms in functional dyspepsia remains a matter of debate.Moreover,further evaluation of distal gastric volume that has been previously implicated in the origin of functional dyspeptic symptoms is advisable.Therefore,impaired gastric accommodation does not serve as a clear marker of the cardinal symptoms experienced by patients with functional dyspepsia in daily life.