Does Liposuction for Lymphedema Worsen Lymphatic Injury?

Liposuction for treatment of lymphedema is an effective and time-tested treatment. However, as there is a fear regarding further lymphatic damage caused by liposuction, we objectively compared lymphatic function pre- and post-liposuction. All patients with solid-predominant lymphedema who were treated during the study period of June 2014 and November 2018 were included. Patients were assessed using patient-reported baselines/outcomes, lymphedema- specific quality of life scale (LYMQOL), limb circumference/volume measurements, and indocyanine green lymphography (ICGL) preoperatively and at predefined postoperative time intervals. Fifty-seven limbs from 41 patients were included. Mean lipoaspirate volumes were 2035 mL, 5385 mL, and 3106 mL for the arm, thigh, and leg, respectively with a mean adipose fraction of the lipoaspirate of 71%. All patients underwent redundant skin excision with the "flying squirrel" technique. The mean follow-up was 10.7 months (range 3 - 48 months) with a mean limb volume reduction of 32.2% and all patients reporting satisfactory relief of symptoms. All showed statistically significant improvement in LYMQOL in symptoms, appearance, and function. On ICGL, none showed worsened lymphatic drainage, rather, all showed improved lymph drainage. Furthermore, the improved lymph drainage was found to be progressive during the study period in all patients. Our study results demonstrate that treating extremity lymphedema with liposuction does not worsen lymphatic function and in fact, paradoxically, it induces progressive improvement in lymph drainage.

Correlation between lipid-lowering therapy and cerebral microbleeds

OBJECTIVE

To investigate if there is a correlation between lipid-lowering treatment with statins and the occurrence, number, and location of cerebral microbleeds (CMBs) among patients with ischemic cerebrovascular disease (ICVD), and also to compare treatment with atorvastatin and rosuvastatin in terms of the occurrence of CMBs and their differences.

METHODS

In this retrospective study, we included patients who were diagnosed with ICVD and underwent susceptibility weighted imaging (SWI) in a grade A tertiary hospital from October 1, 2014 to October 1, 2022. We collected information on previous statin use, past medical history, clinical test indicators, and imaging data.

RESULTS

We found that out of 522 patients, 310 patients (59.4%) had no CMB and 212 patients (40.6%) had CMBs. There was no statistically significant correlation between prior statin use, the occurrence, and number of CMBs in patients diagnosed with ICVD (P < 0.05). As for the location of CMB, there was a statistically significant correlation between prior statin use and lobar CMBs (P < 0.048). However, there was no statistically significant correlation between the use of atorvastatin and rosuvastatin and the occurrence of CMBs (P > 0.05).

CONCLUSION

There was no independent correlation between previous statin use, and the occurrence, and number of CMBs in patients with ICVD. As for CMBs in different locations, there was a correlation between previous use of statin and lobar CMBs. There was no significant difference between atorvastatin and rosuvastatin in the occurrence of CMBs in patients with ICVD.

Smartphone use increases the likelihood of making short-sighted financial decisions

Contextualizing in the digitalization of personal finance (e.g., mobile banking), the present research explores how financial decisions made on smartphones (vs. laptops or tablets) are more likely to be shortsighted, manifesting in being unwilling to save for retirement, referring to recent information while making financial decisions, and opting for instant but smaller rewards. We trace the effect to smartphones’ affordance of ubiquity, an attribute that allows users to satisfy various needs with considerable flexibility of time and space and prompts users to seek instant gratifications. We also rule out potential alternative factors that might account for this effect, including haptic gratification, direct-touch effect, task difficulty, thinking style, concentration, and the hedonic usage of the devices by users. Furthermore, we demonstrate that prompting users to deliberate on their decisions successfully attenuates the effect. Implications for the development of interventions are discussed.

Potential of Bradyrhizobia inoculation to promote peanut growth and beneficial Rhizobacteria abundance

AIMS

To investigate the effects of three symbiotic Bradyrhizobium strains on peanut growth and on rhizobacterial communities in flowering and harvest stages in an organic farm, also to evaluate the role of plant development in influencing peanut rhizobacterial microbiota and correlations among the inoculants, rhizobacterial communities and plant growth.

METHODS AND RESULTS

Peanut seeds were inoculated with three individual Bradyrhizobium strains, plant growth performance was measured in two developmental stages and rhizobacterial communities were analysed by Illumina sequencing of rpoB gene amplicons from peanut rhizosphere. The three bradyrhizobial inoculants significantly increased the nodule numbers and aboveground fresh weight of peanut plants regardless of the different growth stages, and the pod yields were increased to some extent and significantly positively correlated with Bradyrhizobium abundances in rhizosphere. Principal coordinate analysis indicated that the rhizobacterial communities were strongly influenced by the inoculation and peanut developmental stages. The bradyrhizobia inoculation increased relative abundances of potentially beneficial bacteria in peanut rhizosphere, and also altered rhizobacterial co-occurrence association networks and important network hub taxa. Similarly, plant development also significantly influenced the structure, composition and co-occurrence association networks of rhizobacterial communities.

CONCLUSIONS

Bradyrhizobial inoculants increased peanut growth and yields, they and plant development affected the assembly of peanut rhizobacterial communities.

SIGNIFICANCE AND IMPACT OF THE STUDY

Rhizobial inoculants improved the host plant performance that might also be associated with the dynamic changes in rhizobacterial community except enhancing the biological nitrogen fixation and helps to profoundly understand the mechanism how rhizobia inoculants improve plant growth and yields.

Bradyrhizobium arachidis mediated enhancement of (oxy)matrine content in the medicinal legume Sophora flavescens

Effect of rhizobial inoculation and nitrate application on the content of bioactive compounds in legume plants is an interesting aspect for interactions among microbes, plants and chemical fertilizers, as well as for cultivated practice of legumes. In this study, nitrate (0, 5 and 20 mmol l^-1 ) and Bradyrhizobium arachidis strain CCBAU 051107^T were applied, individually or in combination, to the root rhizosphere of the medicinal legume Sophora flavescens Aiton (SFA). Then the plant growth, nodulation and active ingredients including (oxy)matrine of SFA were determined and compared. Rhizobial inoculation alone significantly increased the numbers and fresh weight of root nodules. Nodulation was significantly inhibited due to nitrate (5 and 20 mmol l^-1 ). Only oxymatrine was detected in the control plants without rhizobial inoculation and nitrate supplement, while both oxymatrine and matrine were synthesized in plants treated with inoculation of B. arachidis or supplied with nitrate. The content of oxymatrine was the highest in plants inoculated solely with rhizobia and was not significantly altered by additional application of nitrate. Combinations of B. arachidis inoculation and different concentrations of nitrate did not significantly change the concentrations of (oxy)matrine in the plant. In conclusion, sole rhizobial inoculation was the best approach to increase the contents of key active ingredients oxymatrine and matrine in the medicinal legume SFA.

Recent development and new insight of diversification and symbiosis specificity of legume rhizobia: mechanism and application

Currently, symbiotic rhizobia (sl., rhizobium) refer to the soil bacteria in α- and β-Proteobacteria that can induce root and/or stem nodules on some legumes and a few of nonlegumes. In the nodules, rhizobia convert the inert dinitrogen gas (N₂ ) into ammonia (NH₃ ) and supply them as nitrogen nutrient to the host plant. In general, this symbiotic association presents specificity between rhizobial and leguminous species, and most of the rhizobia use lipochitooligosaccharides, so called Nod factor (NF), for cooperating with their host plant to initiate the formation of nodule primordium and to inhibit the plant immunity. Besides NF, effectors secreted by type III secretion system (T3SS), exopolysaccharides and many microbe-associated molecular patterns in the rhizobia also play important roles in nodulation and immunity response between rhizobia and legumes. However, the promiscuous hosts like Glycine max and Sophora flavescens can nodulate with various rhizobial species harbouring diverse symbiosis genes in different soils, meaning that the nodulation specificity/efficiency might be mainly determined by the host plants and regulated by the soil conditions in a certain cases. Based on previous studies on rhizobial application, we propose a '1+n-N' model to promote the function of symbiotic nitrogen fixation (SNF) in agricultural practice, where '1' refers to appreciate rhizobium; '+n' means the addition of multiple trace elements and PGPR bacteria; and '-N' implies the reduction of chemical nitrogen fertilizer. Finally, open questions in the SNF field are raised to future think deeply and researches.

[Therapeutic effect of tonsillectomy on IgA nephropathy after kidney transplantation]

Objective: To observe the clinical effect of tonsillectomy on IgA nephropathy (IgAN) after renal transplantation. Methods: From March 2011 to July 2018, 201 kidney transplantation recipients who were diagnosed of IgAN by transplant renal biopsy in the Department of Organ Transplantation of the First Affiliated Hospital of Sun Yat-sen University were retrospectively reviewed, of which 18 patients underwent tonsillectomy after renal biopsy. The clinical data of the 18 patients were collected, patient and kidney survival time and function of the transplanted kidney were analyzed. Results: Of the 18 recipients, 13 were male and 5 were female, with an average age of (36.0±10.9) years. All 18 patients survived during follow-up. Two patients returned to dialysis treatment 10 months and 14 months after tonsillectomy, respectively. The creatinine was 94 (78, 133) μmol/L, 95 (74, 139) μmol/L, 106 (87, 158) μmol/L and 95(81, 147) μmol/L before tonsillectomy, 3 months, 1 year and 2 years after tonsillectomy, respectively (P=0.206). Urinary protein quantification was 0.31 (0.16, 1.38) g/24 h, 0.34 (0.10, 1.42) g/24 h, 0.33 (0.11, 0.56) g/24 h and 0.25 (0.10, 0.50) g/24 h at the same time points, respectively (P=0.104). The two patients who returned to dialysis were diagnosed of IgAN by transplant renal biopsy because of elevated creatinine, proteinuria and hematuria, 9 years and 4 years after kidney transplant respectively. Renal biopsy suggested that glomerular and segmental sclerosis were 7/24, 5/24 and 1/6, 2/6, respectively. Additionally, interstitial fibrosis and tubular atrophy (IF/TA) were both occupied 30% in the biopsies, and tonsillectomy was performed 461 days and 1 077 days after diagnosis of IgAN, respectively. Conclusions: Tonsillectomy can maintain the stability of renal function and prevent the aggravation of proteinuria in IgAN patients after renal transplantation. However, if pathology suggests obvious glomerulosclerosis or IF/TA, tonsillectomy may not be effective.

[A novel and simplified closure method for defect closure after endoscopic full-thickness resection of gastric submucosal tumors: short-term outcomes of "Shao-Mai" closure method]

Objective: To evaluate the feasibility and short-term efficacy of a novel and simplified closure method developed by our team for the defect closure after endoscopic full-thickness resection (EFTR) for gastric submucosal tumors (SMT) in the gastric wall. Methods: A prospective single-arm clinical study was used. Inclusion criteria: (1) the lesion was located in the fundus or the greater curvature of the stomach, and was confirmed to originate from the muscularis propria layer; (2) the diameter of the tumor was ≤3.5 cm, and the tumor had no extensive adhesion to the peritoneal tissues and organs in extraperitoneal cavity; (3) the tumor had no malignant features under ultrasound endoscopy; (4) the patient agreed to participate in the study; (5) patients with severe complications were excluded. Based on the above criteria, 20 patients with gastric SMT at the Endoscopy Center of Zhongshan Hospital of Fudan University from January 2015 to March 2018 were enrolled in this study, including 5 males and 15 females with mean age of 61.1 (38 to 70) years. Grasping forceps-assisted endo-loop snare ligation device which is called "Shao-Mai" method was used to close the defect site. All the patients underwent EFTR and "Shao-Mai" method to perform defect closure. After successful tumor resection by EFTR, an endo-loop was anchored onto the edge of the gastric defect with grasping forceps assistance and closed tightly. The observation indicators included tumor size, en bloc resection, operation time, postoperative complications and hospital stay. The follow-up indicators included tumor residual, local recurrence, and metachronous lesions. Results: All the 20 lesions were located in the muscularis propria with a size of 0.5-3.5 (mean 1.4) cm. Three of them were located in the greater curvature of the mid-upper gastric body, 17 were located in the fundus. The endoscopic "Shao-Mai" closure was successfully performed after EFTR in all the 20 cases. Endoscope was used uniquely through the entire process, without laparoscopic assistance. The operative time was 20-100 (mean 43.8) minutes, while the "Shao-Mai" closure procedure took a range of 3-30 (mean 10.1) minutes. The en bloc resection rate was 100%. The pathological diagnosis included 17 gastrointestinal stromal tumors and 3 leiomyomas. No major complications occurred during or after surgery. All the patients were discharged 1-11 (mean 3.1) days after operation. The wounds of all the cases were healed completely six months after operation and only scar was observed without ulcer. No residual lesion, tumor recurrence or metastasis, leakage or fistula of digestive tract were found during the follow-up period of 15-54 (median 41) months. Conclusion: The endoscopic "Shao-Mai" closure method is a simplified novel way, which is feasible, effective, and safe for closing the gastric defect after EFTR.

[Application value of dual channel dual curved endoscope in the endoscopic submucosal dissection for gastric angle mucosal lesions]

Objective: To evaluate the clinical value of dual channel dual curved endoscope in the endoscopic submucosal dissection (ESD) for gastric angle mucosal lesions. Methods: A descriptive cohort study was carried out. Clinicopathological data of 20 cases with gastric angle mucosal lesions undergoing ESD by dual channel dual curved endoscope in our center from October 2016 to August 2018 were collected and analyzed retrospectively. Inclusion criteria: (1) the lesion was located in the gastric angle confirmed by gastroscopy before ESD. (2) CT examination showed no distant metastasis. (3) pathological biopsy confirmed precancerous lesion or early cancerous lesion without submucosal invasion. (4) the whole operation was performed by the same endoscopist with ESD experience of about 2000 cases. Patients with previous ESD history of gastric angle and other serious diseases were excluded. The dual channel dual curved endoscopy (Olympus, GIF-2TQ260M) and other conventional endoscopic surgical instruments were used in all the cases. Complete tumor resection rate, pathological results, intraoperative and postoperative complications, operation time and hospitalization time were observed. Follow - up parameters included residual tumor, local recurrence and heterogeneous lesion. Results: Of 20 patients, 14 were male and 6 were female with an average of 55.6 years (range, 37 to 75). All the tumors located in gastric angle. Specimen size ranged from 1.2 to 5.5 (average 2.9) cm. Operation time ranged from 50 to 120 (average 85.8) minutes. Hospital stay ranged from 3 to 7 (average 5.1) days. The en bloc excision was performed successfully in all 20 cases. There was no perforation or bleeding during or after operation. Pathological results showed curative or nearly curative resection stage in all the cases. No tumor residual or recurrence was found during follow-up for 8 to 30 (average 18.5) months. Conclusion: Dual channel dual curved endoscope can provide good vision and easy control in removing the lesion completely and avoiding complications during the ESD procedure in gastric angle mucosal lesions with good long-term efficacy.

Rhizobial biogeography and inoculation application to soybean in four regions across China

AIMS

The aim of the study was to survey rhizobial biogeography and to inoculate soybean with selected rhizobia in China to enhance symbiotic nitrogen fixation (SNF).

METHODS AND RESULTS

Biogeography, genetic diversity and phylogeny of soybean rhizobia were surveyed. Inocula were prepared and applied to soybean. Results showed that Bradyrhizobium elkanii and Ensifer fredii were widely distributed in acid and alkaline soils respectively. Available iron was detected as the first determinant for distribution of the two rhizobia and the soybean varieties did not greatly affect the rhizobial compatibility. Geographical latitude and precipitation in June were the main geographical and climatic factors affecting the rhizobial distribution. Inoculation with selected rhizobia increased the nodule number, fresh weight, occupation ratio, seed protein content and soybean yields.

CONCLUSIONS

Selection and application of effective soybean rhizobia across China according to biogeography were clarified to promote the SNF, thereby improving soybean yield.

SIGNIFICANCE AND IMPACT OF THE STUDY

Rhizobial diversity and biogeography were evaluated systematically in six sites across China. Available iron and soil pH are found to be the most important determinants for the distribution of soybean rhizobia. Inoculation to soybean enhances SNF, positively correlating to the increase in soybean yield and seed protein content.

[Clinical comparison of modified laparoscopic and conventional placement of peritoneal dialysis catheters]

Objective: To explore the clinical efficacy of the modified laparoscopic placement of peritoneal dialysis catheters by nephrologists. Methods: A total of 188 patients diagnosed as end-stage renal disease (ESRD) were enrolled, who received catheter and continuous ambulatory peritoneal dialysis (CAPD) therapy from January 2011 to May 2016 in Zhejiang Provincial People's Hospital. They were divided into group A (with modified laparoscopic placement of peritoneal dialysis catheters, n=59) and group B (with conventional placement of peritoneal dialysis catheter, n=129). The demographic and clinical characteristics, past abdominal operation history, surgery time, hospital stay after operation, expenses for surgery and hospitalization, early and late complications including bleeding, pain, leakage, peritonitis and catheter displacement were observed. Results: Patients with previous abdominal surgery accounted for 11.9% in group A and 0 in group B(χ²=15.897, P<0.001). The duration of the operation was (38.9±12.8)min in group A and (64.1±12.7)min in group B(t=-6.466 6, P=0.000 0). The cost of the operation was (5 488.4±156.1) yuan in group A and (1 602.7±48.92) yuan in group B (t=257.129, P=0.000 0). Catheter displacement within one month was observed in 0 and 11.6%(χ²=7.455 3, P=0.003), pain in 15.3% and 41.9% (χ²=12.862 2, P=0.000), and catheter displacement after one month in 0 and in 16.3% (χ²=10.812 4, P=0.000) of the patients, respectively in group A and group B. The incidences of peritonitis within one month and beyond one month, leakage, bleeding and so on showed no difference between the two groups(P>0.05). Conclusions: Placement of PD catheter with laparoscope is suitable for renal failure patients with abdominal operation history and replacement PD catheter. It also has the advantages of shorter surgery time, less pain and lower incidences of catheter displacement, expanding the application of PD. However, bleeding, leakage, hernia and other complications are frequently seen.

[Focal segmental glomerulosclerosis after renal transplantation in a child with ANCA-associated glomerulonephritis: case report and literature review]

Objective: To study the clinical features and treatment of focal segmental glomerulosclerosis (FSGS) after renal transplantation in a child with ANCA-associated glomerulonephritis. Method: The clinical and pathological data of the patient treated in the Department of Pediatrics as well as in the Department of Organ Transplantation in November 2015 in the First Affiliated Hospital of Sun Yat-sen University, who was diagnosed with de novo FSGS after renal transplantation with a primary disease ANCA-associated glomerulonephritis, was analyzed retrospectively. Reports on "ANCA-associated glomerulonephritis" "(renal OR kidney) transplantation" "focal segmental glomerular sclerosis" were searched and reviewed. Result: A ten years old female was definitely diagnosed with ANCA-associated glomerulonephritis on the 81^st day after the onset of primary ANCA associated glomerulonephritis. Because of progressive decline of renal function, a hemodialysis period for 7 months was administered following the pulsed methylprednisolone as well as cyclophosphamide treatment. The renal transplantation was then carried out 18 months later, the renal function recovered 7 days later while proteinuria reappeared 28 days after renal transplantation. Based on the anti-rejection treatment, 3 times pulsed methylprednisolone administration did not make difference on reducing the proteinuria and then a renal biopsy was conducted and the transplanted kidney proved to be a newly developed FSGS. Consequently, plasma exchange therapy was administrated. When the plasma exchange course finished, the proteinuria decreased significantly (from 3.270 g/24 h to 0.370 g/24 h). No reports were retrieved either in Chinese databases or at PubMed as well as Medline databases. Conclusion: FSGS appears in transplanted kidney in patient with a primary renal disease as ANCA associated glomerulonephritis with early proteinuria after transplantation as well as negative P-ANCA and MPO. Pathology of renal biopsy revealed FSGS while the pathology of other recipient was not FSGS. The patient had no response to pulsed methylprednisolone therapy. Instead, plasma exchange therapy was an alternative also effective treatment for de novo FSGS in transplanted kidney.

Differential chemotactic potential of mouse platelet basic protein for thymocyte subsets

Mouse platelet basic protein (CXCL7/mPBP) was cloned from thymic stromal cells and further identification indicated that it was expressed in thymic monocytes/macrophages (Mo/Mphis). Recombinant mPBP was chemoattractive for target cells of polymorphonuclear leucocytes, peritoneal Mo/Mphis and splenic lymphocytes with distinct potencies. CXCR2 was identified to be a cognate receptor for mPBP. Mouse thymocyte subsets of CD4-CD8- double-negative (DN), CD4+CD8+ double-positive (DP), CD4+CD8- single-positive (CD4SP) and CD4-CD8+ single-positive (CD8SP) expressed cell surface CXCR2 with different positive percentages and expression levels. mPBP was chemoattractive for thymocyte subsets with the potency order DN>DP> CD8SP>CD4SP, consistent with the levels of CXCR2 expressed on the respective cells. Thus, mPBP in thymus is functionally redundant with chemokine CXCL12/ SDF-1. Moreover, our finding that thymic Mo/Mphis can produce mPBP implies that they may have other functions apart from acting as scavengers in thymus.

Is endoscopic sphincterotomy plus large-balloon dilation a better option than endoscopic large-balloon dilation alone in removal of large bile duct stones? A retrospective comparison study

BACKGROUND

Several comparison studies have demonstrated that endoscopic sphincterotomy (EST) combined with large-balloon dilation (LBD) may be a better option than EST alone to manage large bile duct stones. However, limited data were available to compare this combination method with LBD alone in removal of large bile duct stones.

OBJECTIVE

To compare EST plus LBD and LBD alone for the management of large bile duct stones, and analyze the outcomes of each method.

PATIENTS AND METHODS

Sixty-one patients were included in the EST plus LBD group, and 48 patients were included in the LBD alone group retrospectively. The therapeutic success, clinical characteristics, procedure-related parameters and adverse events were compared.

RESULTS

Compared with EST plus LBD, LBD alone was more frequently performed in patients with potential bleeding diathesis or anatomical changes (P = 0.021). The procedure time from successful cannulating to complete stone removal was shorter in the LBD alone group significantly (21.5 vs. 17.3 min, P = 0.041). The EST plus LBD group and the LBD alone group had similar outcomes in terms of overall complete stone removal (90.2% vs. 91.7%, P = 1.000) and complete stone removal without the need for mechanical lithotripsy (78.7% vs. 83.3%, P = 0.542). Massive bleeding occurred in one patient of the EST plus LBD group, and successfully coagulated. Postoperative pancreatitis did not differ significantly between the EST plus LBD group and the LBD alone group (4.9% vs. 6.3%; P = 1.000).

CONCLUSION

Endoscopic sphincterotomy combined with LBD offers no significant advantage over LBD alone for the removal of large bile duct stones. LBD can simplify the procedure compared with EST plus LBD in terms of shorten the procedure time.

Submucosal tunneling endoscopic resection for upper gastrointestinal multiple submucosal tumors originating from the muscular propria layer: a feasibility study

BACKGROUND AND AIMS

In recent years, submucosal tunneling endoscopic resection (STER) was applied more and more often for single gastrointestinal (GI) submucosal tumor (SMT). However, little is known about this technique for treating multiple SMTs in GI tract. In the present study, we investigated the feasibility and outcome of STER for upper GI multiple SMTs originating from the muscularis propria (MP) layer.

PATIENTS AND METHODS

A feasibility study was carried out including a consecutive cohort of 23 patients with multiple SMTs from MP layer in esophagus, cardia, and upper corpus who were treated by STER from June 2011 to June 2014. Clinicopathological, demographic, and endoscopic data were collected and analyzed.

RESULTS

All of the 49 SMTs were resected completely by STER technique. Furthermore, only one tunnel was built for multiple SMTs of each patient in this study. En bloc resection was achieved in all 49 tumors. The median size of all the resected tumors was 1.5 cm (range 0.8-3.5 cm). The pathological results showed that all the tumors were leiomyoma, and the margins of the resected specimens were negative. The median procedure time was 40 min (range: 20-75 min). Gas-related complications were of the main complications, the rates of subcutaneous emphysema and pneumomediastinum, pneumothorax, and pneumoperitoneum were 13.0%, 8.7% and 4.3%. Another common complication was thoracic effusion that occurred in 2 cases (8.7%), among which only 1 case (4.3%) with low-grade fever got the drainage. Delayed bleeding, esophageal fistula or hematocele, and infection in tunnel were not detected after the operation there were no treatment-related deaths. The median hospital stay was 4 days (range, 2-9 days). No residual or recurrent lesion was found during the follow-up period (median 18, ranging 3-36 months).

CONCLUSION

Submucosal tunneling endoscopic resection is a safe and efficient technique for treating multiple esophageal SMTs originating from MP layer, which can avoid patients suffering repeated resections.

Anomalous interface adhesion of graphene membranes

In order to understand the anomalous interface adhesion properties between graphene membranes and their substrates, we have developed a theoretical method to calibrate the interface adhesion energy of monolayer and multilayer graphene on substrates based on the bond relaxation consideration. Four kinds of interfaces, including graphene/SiO₂, graphene/Cu, graphene/Cu/Ni and Cu/graphene/Ni, were taken into account. It was found that the membrane thickness and the interface confinement condition determine the adhesion energy. The relationship between the critical interface separation and the graphene thickness showed that the interface separation in the self-equilibrium state drops with decreasing membrane thickness. The size-dependent Young's modulus of graphene membrane and the interfacial condition were responsible for the novel interface adhesion energy. The proposed theory was expected to be applied to the design of graphene-based devices.

Peroral endoscopic remyotomy for failed Heller myotomy: a prospective single-center study

BACKGROUND AND STUDY AIMS

Recurrence/persistence of symptoms occurs in approximately 20 % of patients after Heller myotomy for achalasia. Controversy exists regarding the therapy for patients in whom Heller myotomy has failed. The aim of the current study was to evaluate the efficacy and feasibility of peroral endoscopic myotomy (POEM), a new endoscopic myotomy technique, for patients with failed Heller myotomy.

PATIENTS AND METHODS

A total of 12 patients with recurrence/persistence of symptoms after Heller myotomy, as diagnosed by established methods and an Eckardt score of ≥ 4, were prospectively included. The primary outcome was symptom relief during follow-up, defined as an Eckardt score of ≤ 3. Secondary outcomes were procedure-related adverse events, lower esophageal sphincter (LES) pressure on manometry, reflux symptoms, and medication use before and after POEM.

RESULTS

All 12 patients underwent successful POEM after a mean of 11.9 years (range 2 - 38 years) from the time of the primary Heller myotomy. No serious complications related to POEM were encountered. During a mean follow-up period of 10.4 months (range 5 - 14 months), treatment success was achieved in 11/12 patients (91.7 %; mean score pre- vs. post-treatment 9.2 vs. 1.3; P < 0.001). Mean LES pressure was 29.4 mmHg pre-treatment and 13.5 mmHg post-treatment (P < 0.001). One patient developed mild reflux symptoms and required intermittent medication with proton pump inhibitors.

CONCLUSIONS

POEM seems to be a promising new treatment for failed Heller myotomy resulting in short-term symptom relief in > 90 % of cases. Previous Heller myotomy may make subsequent endoscopic remyotomy more challenging, but does not prevent successful POEM.

Investigations of mechanical vibrations for beamlines at the Canadian Light Source

Vibration is often a problem causing poor quality of photon beams at synchrotron radiation facilities, since beamlines are quite sensitive to vibrations. Therefore, vibration analysis and control at synchrotron radiation facilities is crucial. This paper presents investigations on mechanical vibrations at four beamlines and endstations at the Canadian Light Source, i.e. the Canadian Macromolecular Crystallography Facility 08ID-1 beamline, the Hard X-ray MicroAnalysis 06ID-1 beamline, the Resonant Elastic and Inelastic Soft X-ray Scattering 10ID-2 beamline, and the Scanning Transmission X-ray Microscope endstation at the Spectromicroscopy 10ID-1 beamline. This study identifies vibration sources and investigates the influence of mechanical vibrations on beamline performance. The results show that vibrations caused by movable mechanical equipment significantly affect the data acquired from beamlines.

Intra-articular magnesium sulfate (MgSO4) reduces experimental osteoarthritis and nociception: association with attenuation of N-methyl-D-aspartate (NMDA) receptor subunit 1 phosphorylation and apoptosis in rat chondrocytes

OBJECTIVE

To study the effects of intra-articular injection of magnesium sulfate (MgSO(4)) on the development of osteoarthritis (OA) and to examine concomitant changes in the nociceptive behavior of rats.

METHODS

OA was induced in Wistar rats with intra-articular injection of collagenase (500 U) in the right knee; the left knee was left untreated. In the OA+MgSO(4) group (n=7), the treated knee was injected with 500-microg (0.1-ml) MgSO(4) twice a week for 5 consecutive weeks starting at 1 week after collagenase injection; in the OA group (n=7), the same knee was injected with the same amount of physiological normal saline. In the MgSO(4) group (n=6), naïve rats received only MgSO(4) injections; in the control group (n=6), naïve rats received only physiological normal saline injections. Nociceptive behavior (mechanical allodynia and thermal hyperalgesia) on OA development was measured before and at 1, 2, 4, 6, and 8 weeks after collagenase injection, following which the animals were sacrificed. Gross morphology and histopathology were examined in the femoral condyles, tibial plateau, and synovia. Immunohistochemical analysis was performed to examine the effect of MgSO(4) on N-methyl-D-aspartate (NMDA) receptor subunit 1 phosphorylation (p-NR1) and apoptosis in the articular cartilage chondrocytes.

RESULTS

OA rats receiving intra-articular MgSO(4) injections showed a significantly lower degree of cartilage degeneration than the rats receiving saline injections. MgSO(4) treatment also suppressed synovitis. Mechanical allodynia and thermal hyperalgesia showed significant improvement in the OA+MgSO(4) group as compared to the OA group. Moreover, MgSO(4) attenuated p-NR1 and chondrocyte apoptosis in OA-affected cartilage.

CONCLUSIONS

Our results indicate that local intra-articular administration of MgSO(4) following collagenase injection in an experimental rat OA model (1) modulates chondrocyte metabolism through inhibition of cell NMDA receptor phosphorylation and apoptosis, (2) attenuates the development of OA, and (3) concomitantly reduces nociception.

[The expression of p97 on the membrane of the reticulocyte and the role in iron uptake in rabbit]

AIM

To investigate the expression of p97 on the membrane of the reticulocyte and the possible role in non-transferrin bound iron uptake.

METHODS

The SDS-PAGE and the radioisotope (59Fe) was used in this investigation.

RESULTS

(1) The protein of the supernatant of reticulocytes was separated on SDS-PAGE. There was one band near 97kDa. The same result was obtained with reticulocytes treated with PI-PLC and the Mean OD of the band was higher than that of untreated reticulocytes. But for the mature erythrocytes, there wasn't apparent band near 97kD. (2) No apparent effect of only PI-PLC treatment on iron uptake by reticulocytes (P > 0.05). Reticulocytes, depleted endogenous-transferrin and then treated by PI-PLC, gave a significant decrease in iron uptake in cytosol and in heme (P < 0.05).

CONCLUSION

The results support the possibility that p97 might be able to be expressed on the membrane of reticulocytes and plays a role in non-transferrin bound iron uptake by this type of cells in rabbit.

[Relationship between dopamine and iron contents in the brain of parkinsonian rats]

Using fast cyclic voltammetry (FCV), atomic absorption/flame emission spectrophotometry and high performance liquid chromatography for electrochemical detection, we studied the change in iron content in the substantia nigra (SN) of 6-hydroxydopamine (6-OHDA) lesioned Parkinsonian (PD) rats and the toxic effect of intranigral injection of iron on DA neurons. The neuroprotective effect of desferrioxamine mesylate was also observed. The results are as follows. (1) The iron content in SN on the lesioned side of 6-OHDA-lesioned PD rats was about three times as high as that in nonstandard PD rats. (2) The iron content in caudate putamen (CPu) on the lesioned side of PD rats was not different from that on the unlesioned side. (3) DA release as well as the content of DA and its metabolites were significantly decreased on the lesioned side of PD rats. (4) In the rats pretreated with intracerebroventricular desferrioxamine mesylate before 6-OHDA injection, the release and content of DA on the lesioned side were not significantly different from those on the unlesioned side. (5) Intranigral injection of 40 micrograms FeCl3 resulted in a dramatic reduction of both DA release and content in CPu. The above results strongly suggest that 6-OHDA reduces the DA release from CPu, in which iron plays an important role. Elevation of iron content in SN is one of the mechanisms responsible for the reduction of DA content. Desferrioxamine mesylate may exert a protective action on dopaminergic neurons.

Heterogeneity within medullary-type TCRalphabeta(+)CD3(+)CD4(-)CD8(+) thymocytes in normal mouse thymus

The functional maturation process of medullary-type CD4(-)CD8(+) [CD8 single-positive (SP)] thymocytes remains largely uncharacterized. We describe a phenotypic analysis of CD8 SP medullary-type thymocytes and find a remarkable heterogeneity within this thymic cell population. While mature CD8(+) T cells in the periphery are relatively homogeneous (TCRalphabeta(+)CD3(+)Qa-2(+) HSA(-)3G11(-)6C10(-)CD69(-)), CD8 SP medullary-type thymocytes contain discrete subpopulations that can be identified by differential expression of several cell-surface markers. We have identified at least six discrete subpopulations in the subset of TCRalphabeta(+)CD3(+) CD8 SP cells in the thymus. According to the expressed phenotypes, a linear developmental pathway is predicted among these CD8 SP subpopulations as follows: 6C10(+)CD69(+)HSA(hi)3G11(+)Qa-2(-) --> 6C10(-)CD69(+)HSA(hi/int)3G11(+)Qa-2(-) --> 6C10(-)CD69(-)HSA(int)3G11(+)Qa-2(-) --> 6C10(-)CD69(-)HSA(lo)3G11(+)Qa-2(-) --> 6C10(-)CD69(-)HSA(-/lo)3G11(-)Qa-2(-) --> 6C10(-)CD69(-)HSA(-/lo)3G11(-)Qa-2(+). This study provides a framework for understanding CD8 SP T cell maturation in the thymic medulla.

Superior sagittal sinus thrombosis induced by thyrotoxicosis. Case report

There is a wide variety of disorders associated with thrombosis of the superior sagittal sinus (SSS), including infectious disease. noninfectious conditions such as vasculitis and hypercoagulable states, and complications arising from pregnancy or use of oral contraceptive medications. Despite these well-defined associations, approximately 25% of the cases remain idiopathic. In this article the authors describe a patient who was found to have SSS thrombosis while experiencing a thyrotoxic phase of Graves disease. The patient presented with intracerebral hemorrhage, subarachnoid hemorrhage, seizure, coma, a raised fibrinogen concentration, low protein C activity, and atrial fibrillations. Thrombolysis was successfully performed despite the coexistence of thrombosis and intracranial hemorrhage. Patients with thyrotoxicosis and a diffuse goiter may be predisposed to the development of SSS thrombosis, as a result of hypercoagulation and stasis of local venous blood flow. In the present case, a patient in whom thrombosis coexisted with intracranial hemorrhage was successfully treated using thrombolytic therapy.

Effect of murine thymic epithelial cell line (MTEC1) on the functional expression of CD4(+)CD8(-) thymocyte subgroups

To determine the effect of thymic stromal cells on the functional maturation of CD4 single-positive (SP) thymocytes, the functional status of isolated CD4 SP thymocyte subgroups was investigated by means of cell proliferation and cytokine production in response to concanavalin A (Con A) prior and after co-culturing with a murine thymic epithelial cell line (MTEC1). Mouse medullary CD4 SP thymocytes were phenotypically divided into seven discrete subgroups predicted to reflect the maturation pathway from newly emerging CD4 SP thymocytes to terminally differentiated cells. For functional analysis, six major subgroups (6C10(+)CD69(+), 6C10(-)CD69(+), 6C10(-)CD69(-)3G11(+)Qa-2(-), 6C10(-)CD69(-)3G11(+)Qa-2(+), 6C10(-)CD69(-)3G11(-)Qa-2(-) and 6C10(-)CD69(-)3G11(-)Qa-2(+)) cells were isolated and their functional status in response to Con A stimulation assessed. A functional hierarchy is revealed among these subgroups, consistent with their phenotypic maturation status, which may imply that these cells undergo a functional maturation process within thymic medulla. The function of cytokine production by CD4 SP thymocytes is acquired in a stepwise manner from a low to high level and characterized by T(h)0-type cytokines in the main stream of differentiation pathway. However, a minor subgroup that appeared at the late stage as 3G11(-)6C10(-) cells was biased to produce T(h)2-type cytokines. Nevertheless, the functional capacity of the final two Qa-2(+) subgroups of CD4 SP thymocytes was still significantly lower than that of spleen CD4(+) T cells. After co-cultivation with MTEC1 cells, four subgroups of TCRalphabeta(+)CD4(+)CD8(-) thymocytes exhibited significantly higher levels of proliferation capability and modulation in cytokine production capability. However, co-culturing with MTEC1 cells did not change the pattern of T(h)0- or T(h)2-like cytokine production by respectively medullary CD4 SP thymocyte subgroups nor could MTEC1 induce CD4 SP thymocytes to secrete T(h)1-type cytokines. The results suggest that MTEC1 can regulate the functional status of these thymocyte subgroups.

[The capability of IL-1 in the induction of chemokine production by murine thymic epithelial cell (MTEC1) clones]

To analyze the capability of IL-1 and IL-6 in the induction of chemokine (CF) production by mouse thymus epithelial cell (MTEC1) clones, MTEC1 cells were cloned through one cell culture and individual cell clones were established in long term culture referred to as MTEC1-DW clones. The constitutive production of IL-1, IL-6 and CF by MTEC1-DW clones was evaluated and the patterns of the cytokine production determined. Addition of exogenous IL-1 or IL-6 or both to the cultures of those MTEC1-DW clones that are unable to produce CF, and incubated for 2 days, then, to assess the chemotactic activity in the cell culture supernatants (SNs). In the opposite, addition of anti-IL-1 mAb(s) to the cultures of those MTEC1-DW clones that can produce IL-1 and CF to neutralize secreted IL-1 then, to test chemotactic activity in the SNs after 2-day incubation. The results showed that in the MTEC1-DW clones which were unable to constitutively produce IL-1 or CF, addition of IL-1 could induce these cloned cells to produce CF with high chemotactic activity. By constrast, addition of anti-IL-1 mAb(s) to those MTEC1-DW clones that constitutively produce IL-1 and CF could significantly inhibit them to produce CF. IL-6 only exhibited weak activity in the induction of CF production by those cloned cells. Therefore, in the cytokine network regulation, CF production is mainly induced by endogenously produced IL-1 in MTEC1 cells.

[Characterization of expression of the apoptosis associated PF18-3 molecule in thymocyte apoptosis following ConA activation]

The expression pattern of McAb PF18-3 recognized molecule in activation induced thymocyte apoptosis was analysed. Results indicated that following activation by ConA, thymocytes underwent activation induced apoptosis identified by delayed production of DNA ladder and TUNEL positive staining of thymocytes in late stage of activation. PF18-3 molecule was found to express specifically in subset of apoptotic thymocytes with diploid. Kinetic comparison of expression between PF18-3 molecule and Fas or translocated membrane phospholipid suggested that PF18-3 molecule is different from them and likely to be a novel molecule related to thymocyte apoptosis.

Phenotypic identification of the subgroups of murine T-cell receptor alphabeta+ CD4+ CD8- thymocytes and its implication in the late stage of thymocyte development

Phenotypic analysis of the medullary-type CD4+ CD8- [CD4 single-positive (SP)] thymocytes has revealed phenotypic heterogeneity within this cell population. The characteristic phenotype of mature peripheral T cells can be uniquely marked as Qa-2+ HSA- CD69-, whereas in the medullary-type CD4 SP thymocytes, the expression patterns of many markers were quite different. This suggests that there are many subgroups in the population, which reflects that medullary-type CD4 SP thymocytes may undergo phenotypic maturation. According to the results of two-colour flow cytometry, seven discrete phenotypes were identified by the expression capacity of Qa-2, HSA, CD69, 3G11 and 6C10 molecules. Consequently, the phenotypic precursor-progeny relationship can be envisaged as: 3G11- 6C10+ CD69+ HSAhi -->3G11+ 6C10+ CD69+ HSAhi --> 3G11+ 6C10- CD69+ HSAint -->3G11+ 6C10- CD69- HSAint Qa-2- -->3G11+ HSA-/lo Qa-2lo. At the stage of 3G11+ 6C10- CD69- HSAint Qa-2-, a branch pathway could be initiated, which gave rise to 3G11- HSAl degrees Qa-2- cells, which then, in turn, developed into 3G11- HSA-/loQa-2hi cells, a minor subgroup of the most mature CD4 SP cells. Consistent with this predicted pathway, experiments indicated that the first two subgroups were still cortisone sensitive, whereas the others were cortisone resistant. The cells in the last two Qa-2-positive subgroups are probably ready for emigration into the periphery.

Cerebellar granule cells acquire transferrin-free iron by a carrier-mediated process

In this study, the mechanism of transferrin-free iron uptake by brain neuronal cells was investigated using the cultured cerebellar granule cells. Effects of incubation time, iron concentration, temperature and other divalent metals on the cellular uptake were determined. After five days of plating, the cells were incubated with different concentrations of transferrin-free iron in isotonic sucrose solution at different temperatures for a certain time. The cellular transferrin-free iron uptake was analysed by measuring the cellular radioactivity with a gamma-counter. The result showed that the cultured cerebellar granule cells had the capacity to acquire transferrin-free iron at pH 6.5, at which it was demonstrated that transferrin binds iron very poorly and only very little transferrin can be internalized by reticulocytes and HeLa cells. The iron uptake by cells increased with incubation time in a linear manner at a rate of 0.1076 pmol/microg protein/min within the first 10 min. The uptake was time- and temperature-dependent, iron concentration saturable, and inhibited by several divalent metal ions, such as Co2+, Zn2+, Mn2+ and Ni2+. These characteristics of transferrin-free iron uptake by the cultured cerebellar granule cells observed in this study, similar to those obtained from cells outside of the brain, implied that a carrier-mediated iron transport system might be present on the membrane of this type of brain neuronal cells. In addition, no significant difference in malondialdehyde measurement was found when the cells were incubated without or with the lower concentrations of iron (< 4 microM) for 20 min at 37 degrees C, demonstrating that this system was valid for studying membrane iron transport in this type of brain neuronal cell.

[Effect of beta-endorphin on plasma sialic acid level in rats and the relationship with the immune function]

With the use of beta-EP microinjection into the central nervous system, spectrophotometrical analysis and immunochemical method we studied the effect of beta-Endorphin (beta-EP) on plasma sialic acid (SA) level. The results indicate: (1) The plasma SA level was significantly decreased after microinjection of beta-EP into the lateral ventricle (LV); (2) When beta-EP was microinjection into nucleus arcuatus (ARC), the plasma SA level was significantly decreased (P < 0.05). This effect can be blocked by i.v. atropine or vagotomy; (3) Microinjection of beta-EP into ARC can cause the increase of CD3, CD4 and CD4/CD8, while CD8 was decreased. The above results suggest that the possible mechanism underlying the decrease of plasma SA level is mediated by cholinergic muscarinic receptor, and the cellular immune function is enhanced.

[Phenotypic analysis of TCR alpha beta+ CD4+CD8- medullary thymocytes]

Phenotypic analysis of the medullary-type CD4+CD8- (CD4SP) thymocytes have revealed phenotypic heterogeneity within these cells. The phenotype of mature peripheral T cells is Qa-2+ HSA- CD69-, whereas in the medullary-type CD4SP thymocytes, the expression pattern of many markers were quite different, suggesting that the medullary-type CD4SP thymocytes may undergo phenotypic maturation. According to the results of two-color cytometry, seven discrete phenotypes were defined by the relative expression of Qa-2, HSA, CD69, 3G11 and 6C10: 3G11-6C10+CD69+HSAhi-->3G11+6C10+CD69+ HSAhi-->3G11+6C10-CD69+HSAint-->3G11+6C10- CD69-HSAint Qa-2(-)-->3G11+HSAlo/-Qa-2lo, at the same time, 3G11+6C10-CD69-HSAint Qa-2(-)-->3G11-HSAlo Qa-2(-)-->3G11-HSAlo/- Qa-2hi, the last two Qa-2 positive subsets could exit the thymus and home into periphery.

Thymic microenvironments, 3-D versus 2-D?

Lympho-stromal interactions in the thymus crucially de- termine the fate of developing T cells. Epithelial cells, inter- digitating reticular cells, macrophages and fibroblasts all play a role in the shaping of the T cell repertoire. Recently published evidence shows that lympho-stromal interaction acts bi-directional. Developing T cell themselves, at different stages of differentiation, control the microarchitecture of thymic microenvironments, a phenomenon designated as 'crosstalk'. This paper reviews experiments showing that developing T cells crosstalk to different thymic epithelial cells in a stepwise fashion. In this way, correctly organized thymic microenvironments guarantee normal thymopoiesis.

[30 kD MCP-1 protein produced by mouse thymic epithelial cell line MTEC1]

A medullary type mouse thymic epithelial cell line MTEC1 can produce chemokines. Crude culture supernant of MTEC1 cells was concentrated by controlled-pore glass beads. One of these chemotactic proteins was isolated from MTEC1 supernatant and purified to homogeneity by heparin-Sepharose affinity chromatography, cation-exchange FPLC and Reverse Phase-HPLC. The chemotactic factor for both lymphocytes and monocytes was identified as a 30 kD protein by SDS-PAGE analysis under reducing conditions. After cleavage of the NH2-terminally blocked protein with formic acid, the amino acid sequence of the internal fragment was analyzed and found to be identical to the amino acid sequence of mouse MCP-1/JE. The protein was hence identified as a glycosylated MCP-1/JE-like chemokine secreted by thymic epithelial cells. The characterization of chemokines produced by thymic stromal cells will benefit the analysis of the mechanism of thymus homing and the finding of new chemokines.

Promotion of ATP and S-140 to ribosome inactivation with camphorin, cinnamomin, and other RNA N-glycosidases

AIM

To study the effect of ATP and extra-ribosomal factors (S-140) on type I and type II RNA N-glycosidases in inactivating ribosome.

METHODS

The activity of ATP and S-140 was determined by characterization of R-fragment in gel. An improved two-step method of cell-free protein synthesis system was used to quantitate the requirements of S-140 in ribosome inactivation.

RESULTS

IC50 ratios of camphorin, gamma-momorcharin, luffin S, luffin A, trichosanthin (type I); and ricin, ricin A-chain; cinnamonin, cinnamomin A-chain (type II) between the absence and presence of ATP and S-140 were 3108, 151, 51, 45, 15; and 47, 7, 26, 12, respectively.

CONCLUSION

The ribosome-inactivating activity of type II ribosome-inactivating proteins, including intact protein and its A-chain, was promoted by ATP and S-140. Camphorin showed a significant difference from cinnamomin in need of ATP and S-140 for such promoting.

[Multiple types of cytokines secreted by a mouse fetal liver stromal cell line]

A murine fetal liver stromal cell line, called MFLC, has been established and maintained in DME supplemented with 10%NCS for 2 years. Without exogenous stimulation, the MFLC cells spontaneously secreted several types of cytokines, including IL-6, GM-CSF and chemotactic factor. Of which, IL-6 and chemotactic factor were abundant, GM-CSF at low level. Biological activities of IL-7 and IL-3 were not detected in the MFLC cell's supernatants. MFLC-SN induced colony formation of murine bone marrow cells in a dose dependent fashion in which mixed granulocyte/macrophage/megakaryocyte colonies(CFU-GMM) and granulocyte/macrophage colonies(CFU-GM) were dominant. MFLC-SN also sustained colony formation of bone marrow cells taken from 5-Fu injected mice, suggesting that there was a biological activity similar to SCF in MFLC-SN. The cytokines secreted by MFLC might play an important role in T cell early development in fetal liver. These results will be useful for us to analyse the mechanism of T cell development in fetal liver and to study the cytokine network regulation.

Large-scale preparation of two new ribosome-inactivating proteins--cinnamomin and camphorin from the seeds of Cinnamomum camphora

An improved method for large-scale preparation of cinnamomin and camphorin from the seeds of Cinnamomum camphora has been developed. Cinnamomin is a type II ribosome-inactivating protein (RIP), while camphorin is a type I RIP. Cinnamomin was purified by a single step of acid-treated Sepharose 4B affinity chromatography instead of gel filtration. Camphorin was purified by anion-exchange chromatography and gel filtration successively from the eluant not retained by the affinity column. Using this improved method, 620 mg of cinnamomin and 14.2 mg of camphorin were obtained from 500 g of wet seed, while only 10.6 mg of cinnamomin and 4.7 mg of camphorin were obtained by the previous method. Cinnamomin and camphorin purified by this method were homogeneous in SDS-denatured polyacrylamide gel electrophoresis. These two RIPs are multifunctional proteins. The assay of the enzymatic activities of cinnamomin and camphorin showed that both of them exhibit RNA N-glycosidase and supercoil-dependent endonuclease activities, while camphorin also exhibits superoxide dismutase activity.

Surgical management of grades III and IV primary vesicoureteral reflux in children with and without acute pyelonephritis as breakthrough infections: a comparative analysis

PURPOSE

Although high grade vesicoureteral reflux associated with breakthrough infection may be an indication for surgical intervention, it remains uncertain whether acute pyelonephritis as breakthrough infection is a risk for renal scar formation and whether surgery performed without it has any advantage. We assessed the results of antireflux surgery for high grade vesicoureteral reflux in children with and without acute pyelonephritis as breakthrough infections.

MATERIALS AND METHODS

A total of 33 boys and 27 girls (102 refluxing units) less than 3 years old with grades III and IV vesicoureteral reflux who underwent surgical management because of breakthrough infections were retrospectively studied in a 3-year period. Of the 60 patients 30 (group 1) presented with breakthrough infections of acute pyelonephritis, although they were maintained on prophylactic antibacterials. The remaining 30 patients (group 2) underwent surgery without acute pyelonephritis as the breakthrough infections. There was no renal scar formation at the diagnosis of vesicoureteral reflux in either group. Patients with renal scars were excluded from study. There was no significant difference in patient gender (p = 0.795) or distribution of bilateral vesicoureteral reflux (p = 0.781) in the groups. Group 1 patients were significantly younger at the diagnosis of vesicoureteral reflux (p = 0.006).

RESULTS

Although 55 patients presented with a febrile urinary tract infection at the diagnosis of vesicoureteral reflux, the infection was not significantly related to the development of renal scars (p = 0.066). Of the 55 patients 12 presented with acute pyelonephritis as the initial episode of urinary tract infection. The presence of acute pyelonephritis at the diagnosis of vesicoureteral reflux was also not significantly related to renal scar formation (p = 0.207). Postoperative urinary tract infections developed in 34 patients but there was no significant correlation between postoperative urinary tract infections and renal scar formation (p = 0.235). At followup 17 group 1 and 7 group 2 patients (29 renal units) were found to have renal scars.

CONCLUSIONS

Renal scars were significantly more common in younger children with than without acute pyelonephritis as breakthrough infections (p = 0.010). Although breakthrough infections in high grade reflux may be an indication for antireflux surgery, the most appropriate results were achieved when acute pyelonephritis was not a breakthrough infection.

Early versus late surgical management of fetal reflux nephropathy

PURPOSE

Considering that infants with reflux nephropathy may be susceptible to urinary tract infection or longer postnatal vesicoureteral reflux, an early antireflux procedure rather than chemoprophylaxis may be indicated after birth.

MATERIALS AND METHODS

In 15 male and 7 female neonates bilateral and unilateral primary high grade vesicoureteral reflux was detected prenatally in 15 and 7, respectively, on the basis of dilatation of the urinary tract. There was grade III or IV reflux in the 37 refluxing renal units and all patients received chemoprophylaxis after birth. In 11 neonates congenital reflux nephropathy was diagnosed during month 1 of life, including 5 (9 refluxing renal units) who underwent early antireflux surgery without evidence of urinary tract infection and 6 (11 refluxing renal units) who underwent late surgery with a history of urinary tract infection. All patients treated nonsurgically and surgically were monitored up to 2 years and for 2 years postoperatively, respectively.

RESULTS

Of the 11 patients (17 renal units) without congenital reflux nephropathy reflux improved in 53%, a documented urinary tract infection occurred in 2 and there was no development of new scars in a previously normal kidney. In the 11 patients (20 renal units) with congenital reflux nephropathy the parenchymal defect detected during month 1 of life was general or focal, that is at the mid zone as well as the poles. Surgery was performed at a mean of 8 weeks of life in 5 patients without a documented urinary tract infection, 24 weeks earlier than in the 6 with a history of urinary tract infections. Postoperative breakthrough infections occurred in all 6 infants who underwent late surgery and in none who underwent early surgery (p < 0.05). New scarring developed in previously scarred renal units but there was more new scarring in the renal units treated with late surgery (10 of 11, 90%) than in those treated with early surgery (2 of 9, 22%, p < 0.001). In both groups retardation of growth was identified in the renal units with general nephropathy.

CONCLUSIONS

Renal units with fetal reflux nephropathy were susceptible to urinary tract infections and new scar formation. Early antireflux surgery performed before a urinary tract infection develops offers a better prognosis than late surgery.

[Early T cell development in gene-targeted mutant mice]

Early intrathymic T cell development is highly coordinated and controlled by the interaction of a variety of molecules. The development of gene targeting technology provided a valuable tool to study the function of these molecules in vivo. The analysis of TCR and CD3 gene targeted mice indicated that CD44-CD25+ is a control point in early T cell development. At this stage, the expression of pre-TCR complex (composed of pre-TCR alpha, TCR beta and CD3) and/or its combination with unknown ligand provide signals for further progression beyond the CD44-CD25+ stage. The deficiency of any component in pre-TCR complex would lead to the blockage of T cell development at early stages.

Isolation of a lymphocyte chemotactic factor produced by the murine thymic epithelial cell line MTEC1: identification as a 30 kDa glycosylated form of MCP-1

A medullary-type murine thymic epithelial cell line (MTEC1) established in our laboratory constitutively produces multiple species of chemotactic factors, which attract lymphocytes, neutrophils, and monocytes. Chemotactic proteins were isolated from MTEC1 supernatant and purified to homogeneity by adsorption to controlled pore glass, heparin-Sepharose chromatography, cation-exchange FPLC and RP-HPLC. A chemotactic factor for both lymphocytes and monocytes was identified as a 30 kDa protein by SDS-PAGE analysis under reducing conditions. After cleavage of the NH2-terminally blocked protein with formic acid, the amino acid sequence of the internal fragment was analysed and found to be identical to the amino acid sequence of mouse MCP-1/JE. The protein is hence identified as a glycosylated natural form of MCP-1/JE secreted by thymic epithelial cells. The 30 kDa glycosylated form of MCP-1 shows lower specific chemotactic activity (CA) for both lymphocytes and monocytes than the 6-7 kDa unglycosylated form of MCP-1.

[CD4-CD8- to CD4-CD8+ transition induced by anti-CD3 mAb in vitro cell culture system]

In our experiments, we have observed the effect of anti-CD3 mAb in inducing the differentiation of CD4-CD8- (double negative, DN) thymocytes into CD4+ CD8+ (double positive, DP) cells in an in vitro cell culture system including IL-7 for maintaining the growth of TN thymocytes. When TN thymocytes were stimulated by immobilized anti-CD3 mAb for 3 days, CD4-CD8+ cells generated, which were mostly immediate precursors of CD4+CD8+ thymocytes according to their surface TCR beta expression. The transition from DN to DP thymocytes accompanied with downregulation of interleukin 2 receptor (IL-2 R) alpha chain, and the TCR alpha beta-CD3 expression induced by IL-7 was also inhibited. Anti-CD3 mAb was effective only before the appearance of functional TCR-alpha beta-CD3 complex. Taking together, the results strongly suggest that anti-CD3 mAb induced DN thymocyte defferentiation is through the pre-TCR complex.

[Analysis of chemokine (S) produced by mouse thymic stromal cell lines]

By using Boyden Chamber and PACS methods, we analysed the chemotactic activity of five mouse thymic stromal cell (MTSC) lines' culture supernatant for neutrophil, monocyte/macrophage and lymphocyte, and the phenotype of the attracted lymphocyes, MTEC 1, MTEC 2, MTEC 3, MTEC 5 are mouse thymus epithelial cell lines. MTDC 4 is a mouse thymus dendritic cell line. The results indicate that all of the five MTSC supernatants have chemotactic activity for the target cells mentioned above but in different degree. Chemokines produced by the MTSC cells can be classified into three categories: (1) Chemokines produced by MTEC 1 and MTEC 2 are more potent for the attraction of neutrophils and lymphocytes. (2) MTDC 4 derived chemokines are highly potent for the attraction of monocytes/macrophages. (3) Chemokines produced by MTEC 3 and MTEC 5 are equally attractive to neutrophils, lymphocytes and monocytes/macrophages. Most of the MTSC-SN are more potent for the migration of B lymphocyte than for T lymphocyte. The MTSC-SN exhibits higher chemotactic activity to CD4-CD8+ T cell subset than to CD4+CD8-T cell subset. The characterization of chemokines in MTSC-SN will benefit the finding of new chemokines and the analysis of the mechanism of thymus homing.

Alteration of cerebral microcirculation by hemodilution with hemosome in awake rats

Our study showed that hemodilution with modified fluid gelatin resulted in an increase in local cerebral blood flow (LCBF), but no change at all in local cerebral oxygen delivery (LCOD) in rats. Hemosome, a lecithin encapsulated hemoglobin having the oxygen-carrying capacity, was developed to improve LCOD by hemodilution. Therefore, we have hypothesized that LCBF & LCOD would be increased by hemodilution with hemosome. To test this hypothesis, adult male Sprague-Dawley rats weighing approximately 350g were used and divided into the hemodilution and the control groups. Hemosome was made from pig red blood cells and lecithin. It's mean diameter was approximately 0.3 um and hemoglobin concentration was approximately 4g/dl. Isovolemic hemodilution, which lowered the systemic hematocrit from approximately 50% to approximately 30%, was achieved by rapidly replacing blood with the same volume of hemosome. Ten min later, LCBF in 14 brain structures were measured using the 14C-iodoantipyrine technique. Our results showed that LCBF of the control group ranged from 115 +/- 11 ml/100g/min in the medulla to 260 +/- 31 ml/100g/min in the occipital cortex. LCBFs were generally higher (p < 0.05, MANOVA) by 16% in the hemodilution group than in the control group. However LCODs were generally decreased (p < 0.05, MANOVA) by 18% in the hemodilution group than in the control. In conclusion, hemodilution with hemosome indeed improves LCBF but lowers LCOD in awake rats.

[Excitation of hypothalamic nucleus arcuatus neuron induced decrease of plasma sialic acid level in rats]

The effect of sodium glutamate (Glu) on plasma sialic acid (SA) level was studied by means of microinjection into the nucleus arcuatus (ARC) and ultraviolet spectrophotometry. The results indicate: (1) The plasma SA level was significantly decreased after microinjection of Glu into the ARC (P < 0.01). With increasing Glu concentration, the onset of the decrease occurred earlier. (2) When Glu was microinjected into ARC after intraventricular injection of apomorphine, the plasma SA level was significantly decreased (P < 0.01) and the time required to cause the decrease was shortened. (3) When Glu was microinjected into ARC after intraventricular injection of spiperone, no change was found in the plasma SA level (P > 0.05). The above results suggest that the mechanism underlying the decrease of plasma SA level is probably related to modulated dopamine (DA) release of hypothalamic dopaminergic neurons by DA-D2 receptor.