[Clinical effect of laparoscopy for the treatment of biliary stricture after biliary dilatation operation].

Objective: To investigate the safety and effect of laparoscopy for the treatment of biliary stricture after the biliary dilatation operation. Methods: The clinical data of 78 patients,including 27 males and 51 females aged (48.6±14.2)years(range:17 to 76 years),who presented biliary stricture after biliary dilatation operation from January 2017 to June 2021 in the Department of Minimally Invasive Hepatobiliary Surgery,Hunan Provincial People's Hospital,were retrospectively collected,with 38 cases in the laparoscopy group and 40 cases in the laparotomy group. Of the 78 patients,there were 67 cases of cholangiojejunostomy stricture and 11 cases of stricture of the high intrahepatic bile duct. Statistical methods such as t-test and χ2 test were carried out to compare perioperative clinical data and follow-up information between the two groups. Results: Less intraoperative blood loss((102.6±76.4)ml vs. (162.5±105.9) ml, t=-2.874,P=0.005),shorter postoperative stay length of stay((10.5±3.7)days vs. (14.5±6.4)days, t=-3.379,P=0.001) and shorter waiting time for postoperative anal exhaust((2.0±0.6)days vs. (2.5±0.9)days, t=-2.827,P=0.006) were found in the laparoscopy group than that in the laparotomy group,with statistically significant differences. While there was no statistically difference in the operative time((252.8±54.7)minutes vs. (257.4±68.6)minutes,t=-0.331,P=0.742). Postoperative review and follow-up did not show statistically significant differences between the two groups in the residual stone rate(5.3%(2/38) vs. 5.0%(2/40)) and the incidence of recurrent biliary stricture(5.3%(2/38) vs. 7.5%(3/40))(both P>0.05). Conclusion: Laparoscopy may be safe and effective in the treatment of biliary stricture after the biliary dilatation operation,with less trauma,faster recovery compared to laparotomy.

[The diagnostic value of hydrogen sulfide breath test for small intestinal bacterial overgrowth].

Objective: To evaluate the diagnostic value of hydrogen sulfide breath test(SBT) for small intestinal bacterial overgrowth (SIBO). Methods: College students were enrolled to complete gastrointestinal symptom scale, food frequency questionnaire, lactulose hydrogen- methane breath test (LHMBT) and SBT. Based on the correlation between hydrogen sulfide(H2S) and hydrogen or methane gas,the receiver operating characteristic (ROC) curve of H2S was drawn and diagnostic criteria of SBT was defined. Results: A total of 300 subjects including 84 males and 216 females with age 17-32 (21.6±2.4) years were enrolled from April 2019 to December 2019 and divided into two groups.Two hundred and three patients reported SIBO discomforts with 99 (48.8%) LHMBT positive, while 38 (39.2%) were LHMBT positive in 97 health controls. Rise of H2S at 90 min was positively related with that of hydrogen (r=0.516, P<0.01), and H2S levels at 90 min were positively correlated with methane (r=0.632, P<0.01). A rise in H2S of ≥25.0 ppb or H2S levels ≥62.5 ppb at 90 min during lactulose breath test was considered positive for SIBO, that sensitivity, specificity and accuracy were 66.4%,79.1% and 73.3% respectively. H2S levels were significantly related to the amount of Vitamin B12 intake (P=0.011). H2S-positive subjects exhibited a constipation-predominant pattern. Conclusion: SBT is consistent with LHMBT, especially in constipation-predominant patients, which may provide a reference to the diagnosis of SIBO.

[Clinical outcome of open reduction and internal fixation with digastric trochanteric flip osteotomy for acetabular posterior wall fracture with hip dislocation].

Objective: To evaluate the clinical outcome of open reduction and internal fixation via digastric trochanteric flip osteotomy for acetabular posterior wall fracture with hip dislocation. Methods: From January 2014 to December 2016 a total of 39 patients who suffered posterior wall acetabular fracture and hip dislocation and treated in Beijing Jishuitan Hospital were included in this retrospective study. All the patients were divided into two groups according to surgery type. There were 22 cases in osteotomy group who underwent digastric trochanteric flip osteotomy (DTFO) via Kocher-Langenbeck (K-L) approach, while 17 cases in control group who only received surgery via (K-L) approach. The Matta scale was used to evaluate fracture reduction, while functional recovery scale (FRS) and Euro-Quality of 5 Dimension (EQ-5D) were applied to measure the clinical effect. Results: The baseline characteristics were similar for both groups and the mean follow-up period was (48±11) months. All the surgeries were performed successfully. The blood loss (t=1.52, P=0.12), bed days (t=1.22, P=0.25), complication rate (χ²=2.02, P=0.16) and operation time (t=1.31, P=0.23) showed no significant difference between the 2 groups (P>0.05). The fracture reduction (χ²=0.05, P=0.81) were similar between the 2 groups but the excellent rate were higher in osteotomy group. According to evaluation scales the FRS score and EQ-5D index favored osteotomy group(85±13 vs 80±15 and 0.86±0.12 vs 0.80±0.17, respectively, t=2.87, 3.47, both P<0.05). Conclusion: K-L approach with DTFO can provide clearier surgical field which is convenient for procedure, and compared to K-L approach the clinical effect is more satisfactory.

[Application of Chen's pancreaticojejunostomy technique in laparoscopic pancreaticoduodenectomy (116 cases report)].

Objective: To investigate the safety and feasibility of longitudinal transpancreatic U-sutures invaginated pancreatojejunostomy (Chen's pancreaticojejunostomy technique) in laparoscopic pancreaticoduodenectomy (LPD). Methods: Clinical data of 116 consecutive patients who underwent LPD using Chen's pancreaticojejunostomy technique in Hunan Provincial People's Hospital from May 2017 to December 2018 were retrospectively analyzed. Among these patients, 66 were males and 50 were females. The median age was 58 years old (32-84 yeas old). All 116 patients underwent pure laparoscopic whipple procedure with Child reconstruction method, using Chen's pancreaticojejunostomy technique. The intraoperative and postoperative data of patients were analyzed. Results: All 116 patients underwent LPD successfully. The mean operative time was (260.3±33.5) minutes (200-620 minutes). The mean time of pancreaticojejunostomy was (18.2±7.6) minutes (14-35 minutes). The mean time of hepaticojejunostomy was (14.6±6.3) minutes (10-25 minutes). The mean time of gastrojejunostomy was (12.0±5.5) minutes (8-20 minutes). The mean estimated blood loss was (106.0±87.6) ml (20-800 ml). Postoperative complications were: 11.2%(13/116) of cases had postoperative pancreatic fistula (POPF), including 10.3% (12/116) of biochemical fistula and 0.9%(1/116) of grade B POPF, no grade C POPF occurred; 10.3%(12/116) had gastrojejunal anastomotic bleeding; 3.4%(4/116) had hepaticojejunal anastomotic fistula; 3.4%(4/116) had delayed gastric emptying; 4.3% (5/116) had localized abdominal infection; 12.1%(14/116) had pulmonary infection; postoperative mortality were 0(0/116) and 1.7%(2/116) within 30 days and 90 days, respectively. One patient died of massive abdominal bleeding secondary to Gastroduodenal artery pseudoaneurysm rupture, the other patient died of extensive tumor recurrence and metastasis after surgery. Conclusions: Chen's pancreaticojejunostomy technique is safe and feasible for LPD.It is an option especially for surgeons who have not completed the learning curve of LPD.

Short chain fatty acids contribute to gut microbiota-induced promotion of colonic melatonin receptor expression.

Melatonin plays an important role in various gut functions through melatonin receptors. The gut microbiota/gut hormone axis has recently received increasing attention. However, the relationship between the gut microbiota and melatonin receptors has not yet been evaluated. We aimed to determine the effect of the gut microbiota on colonic melatonin receptor expression in germ-free (GF) rats and to further explore the potential mechanism in Caco-2 cells. In this study, GF rats were transplanted with fecal samples from a healthy human donor. Subsequently, 16S rRNA sequencing was performed to analyze the microbial communities. Colon tissue was collected for immunohistochemical analysis. The correlations between melatonin receptor expression and the gut microbiota were assessed. Melatonin receptor expression in Caco-2 cells was detected by Western blot. We found that fecal microbiota transplantation significantly increased the expression of colonic melatonin receptors in GF rats. The amount of fecal Short chain fatty acids (SCFAs) was significantly higher in fecal microbiota transplantation (FMT) rats than in GF rats. SCFA-producing bacteria, such as Alistipes and Blautia, were positively correlated with colonic melatonin receptor expression in FMT rats. Additionally, acetate and propionate significantly increased melatonin receptor-1 expression in Caco-2 cells. Therefore, the gut microbiota may promote melatonin receptor expression, and the mechanism may involve the action of SCFAs. This finding may facilitate the development of new therapeutic treatments for various gastrointestinal disorders.

[Exploration on laparoscopic hepatectomy on central liver tumor: a report of 40 cases].

Objective: To assess the safety and feasibility of the application of the laparoscopic modality in the perioperative treatment of central liver tumors. Methods: Collecting all the clinical information of a total of 40 patients with central liver tumors who received laparoscopic resection treatment carried out at Department of Hepatological Surgery of People's Hospital of Hunan Provincial from January 2016 to December 2018 to take a retrospective review. There were 19 males and 21 females.The age was (59.5±14.5) years (range: 15 to 71 years) . There were 26 cases of primary hepatic carcinoma (24 cases of hepatocellular carcinoma, 2 cases of cholangiocellular carcinoma) , 8 cases of hepatic cavernous hemangioma, 1 case of metastatic hepatic carcinoma, 5 cases of hepatocellular adenoma. The maximum diameter of tumors were (6.2±2.9) cm (range: 2 to 13 cm) . The patient's information about hepatectomy methods, blocking mode and time of blood flow, operation time, intraoperative blood loss, intraoperative blood transfusion rate, post-operative hospitalization time, perioperative reoperation and postoperative complications were collected. Results: A total of 40 patients all were treated with laparoscopic surgery. The surgical procedure was as follows: 2 patients received the right hepatic lobectomy (Ⅴ, Ⅵ, Ⅶ and Ⅷ segments) , 2 patients received the left hepatic lobectomy (Ⅱ, III and Ⅳ segments) , 13 patients received mesohepatectomy (Ⅳ, Ⅰ and Ⅷ segments) , 2 patients received left hepatic trisegmentectomy (Ⅱ, Ⅲ, Ⅳ and Ⅷ segments) , 2 patients received right hepatic trisegmentectomy (Ⅳ, Ⅴ, Ⅵ, Ⅶ and Ⅷ segments) , 7 patients received Ⅷ segmentectomy, 1 patient received Ⅳ segmentectomy, 3 patients received Ⅴ and Ⅷ segmentectomy, 5 patients received hepatic caudate lobe resection (Ⅰ, Ⅸ segments) , and 3 patients received local tumors resection.Pathological results: there were 26 cases of primary hepatic carcinoma (24 cases of hepatocellular carcinoma, 2 cases of cholangiocellular carcinoma) , 8 cases of hepatic cavernous hemangioma, 1 case of metastatic hepatic carcinoma, 5 cases of hepatocellular adenoma; the pathological reports of all malignant tumor cases all showed negative incisal edge. The operative time was (333±30) minutes (range: 280 to 380 minutes) ; the intraoperative hepatic portal occlusion period was (58±13) minutes (range: 30 to 90 minutes) ; the intraoperative hemorrhage was (173±129) ml (range: 20 to 600 ml) ; the intraoperative blood transfusion rate was 2.5% (1/40) ; the postoperative incidence of bile leakage was 2.5% (1/40) , the hospital discharge of 1 patient with bile leakage was approved after conservative treatments like T pipe decompression and adequate drainage; there was 1 case of abdominal infection and 1 case of pulmonary infection, both of which were discharged from the hospital with conservative treatments; there were no other serious postoperative complications. The postoperative hospital stay was (10.7±2.7) days (range: 6 to 16 days) ; there were no perioperative mortality and reoperation cases. Conclusion: In the centers with abundant laparoscopic hepatectomy experiences, the laparoscopic resection is proved to be safe and feasible in the perioperative treatments of central liver tumors by the highly selective cases, the adequate preoperative assessment and reasonable surgical techniques and approach.

[Comparison of gut microbiotal compositional analysis of patients with irritable bowel syndrome through different bioinformatics pipelines].

OBJECTIVE: To assess whether the same biological conclusion, diagnostic or curative effects regarding microbial composition of irritable bowel syndrome (IBS) patients could be reached through different bioinformatics pipelines, we used two common bioinformatics pipelines (Uparse V2.0 and Mothur V1.39.5)to analyze the same fecal microbial 16S rRNA high-throughput sequencing data. METHODS: The two pipelines were used to analyze the diversity and richness of fecal microbial 16S rRNA high-throughput sequencing data of 27 samples, including 9 healthy controls (HC group), 9 diarrhea IBS patients before (IBS group) and after Rifaximin treatment (IBS-treatment, IBSt group). Analyses such as microbial diversity, principal co-ordinates analysis (PCoA), nonmetric multidimensional scaling (NMDS) and linear discriminant analysis effect size (LEfSe) were used to find out the microbial differences among HC group vs. IBS group and IBS group vs. IBSt group. RESULTS: (1) Microbial composition comparison of the 27 samples in the two pipelines showed significant variations at both family and genera levels while no significant variations at phylum level; (2) There was no significant difference in the comparison of HC vs. IBS or IBS vs. IBSt (Uparse: HC vs. IBS, F=0.98, P=0.445; IBS vs. IBSt, F=0.47,P=0.926; Mothur: HC vs.IBS, F=0.82, P=0.646; IBS vs. IBSt, F=0.37, P=0.961). The Shannon index was significantly decreased in IBSt; (3) Both workshops distinguished the significantly enriched genera between HC and IBS groups. For example, Nitrosomonas and Paraprevotella increased while Pseudoalteromonadaceae and Anaerotruncus decreased in HC group through Uparse pipeline, nevertheless Roseburia 62 increased while Butyricicoccus and Moraxellaceae decreased in HC group through Mothur pipeline.Only Uparse pipeline could pick out significant genera between IBS and IBSt, such as Pseudobutyricibrio, Clostridiaceae 1 and Clostridiumsensustricto 1. CONCLUSION: There were taxonomic and phylogenetic diversity differences between the two pipelines, Mothur can get more taxonomic details because the count number of each taxonomic level is higher. Both pipelines could distinguish the significantly enriched genera between HC and IBS groups, but Uparse was more capable to identity the difference between IBS and IBSt groups. To increase the reproducibility and reliability and to retain the consistency among similar studies, it is very important to consider the impact on different pipelines.

[Deltoid ligament augmentation and repairing in ankle fracture associated with deltoid ligament injury and syndesmosis diastasis].

Objective: To evaluate the outcome of the deep component augmentation and superficial component repairing and syndesmosis screw fixation in treating ankle fracture associated with deltoid ligament injury and syndesmosis diastasis. Methods: From January 2014 to December 2017, 16 patients with ankle fracture combined with deltoid ligament injury and syndesmosis diastasis were treated with the deep component augmentation and superficial component repairing in Beijing Jishuitan Hospital.Of the patients, 13 were males and 3 were females, with an average age of (38±10) years (21-57 years). Nine cases were athletic injuries, 4 cases were daily-life injuries and 3 cases were traffic injuries.According to the Weber classification, 6 cases were type B, 10 cases were type C. According to the Lauge-Hansen classification, 6 cases were supination external rotation Ⅳ injury, 9 cases were pronation external rotation Ⅳ injury, 1 case was pronation abduction Ⅲ injury.The surgical treatment method was rigid fixation of the lateral malleolus and deep deltoid ligament augamentation instead of syndesmosis screw fixation.The effect of the surgical method was observed. Results: The average follow up was (24±12) months (6-40 months). The mean degree of dorsiflexion was 17.8°±6.8° (5°-30°), with 3.8°±6.0° (0°-15°) less than that in normal side, the mean degree of plantar flexion was 46.9°±7.9°, with 1.9°±3.9° (0°-10°) less than that in normal side.The mean Philips and Schwartz score was 96.8±5.1 (82-100), the American Orthopaedic Foot and Ankle Society (AOFAS) Score was 97.4±4.6 (84-100). Conclusion: In the treatment of ankle fracture associated with deltoid ligament injury and syndesmosis diastasis, the deep component augmentation and superficial component repairing and proper rehabilitation can benefit the functional recovery.

[Minimally invasive plate osteosynthesis for treatment of proximal humeral fractures through anterolateral acromial approach].

OBJECTIVE: To investigate the feasibility, surgical technique and effect of osteosynthesis for proximal humerus fractures through the minimal incision anterolateral acromion. METHODS: In this study, 32 patients of proximal humeral fractures were selected and treated through the minimal incision antero-lateral acromion between January 2012 and October 2014. Of these patients, there were 19 males and 13 females, with mean age 46 years old (range: 22-78 years). The mechanism of injury was a trauma of simple fall for 21 patients and motor vehicle accident for 11 patients. According to Neer classification, 18 cases had two-part fractures, 12 had three-part fractures, and 2 had four-part fractures. All patients were sustained operation of open reduction and internal fixation. The average delay between trauma and surgery was 4 d (0.5-10.0 d). The operations were performed in invariable operating room with general anesthesia. The fractures were reduced and immobilized with anatomical locking plate through the minimal incision anterolateral acromion during operation. Patients were received passive motion after operation. RESULTS: All the 32 cases were followed up ranging from 3 to 34 months with an average of 11 months. All the fractures were healed. There was neither failure of internal fixation nor incision infection case. The functional results of the shoulder, according to Constant-Murley score was on an average 86 (range: 69-100). CONCLUSION: The treatment for proximal humeral fractures through the minimal incision anterolateral acromion approach is a feasible and effective method, which shows good results for treating proximal humerus fractures with correct indication. There are several advantages compared with conventional deltopectoral approach. They are minimal soft tissue disruption, minimal blood loss and easily to manipulate technique. But it required selection of indication strictly and surgeon's experience.

[Evaluation of the proximal femur geometry in patients with elderly osteoporotic hip fractures].

Objective: To investigate the relationship between the proximal femur geometry and elderly osteoporotic hip fractures. Methods: From May 2015 to December 2015, 137 patients with elderly osteoporotic hip fractures were involved.69 cases were in the fracture group and 68 cases were in the control group.CT scan were performed on all patients and the proximal femur geometry parameters were measured, including the neck width (NW), neck length (NL), neck shaft angle (NSA), femur head diameter (FHD), head height (HH) and Offset.Statistical analysis was performed between two groups. Results: The results of single factor analysis showed that age, sex, NL, FHD, NSA and Offset had significantly differences between two groups (P<0.05). The multiple Logistic regression analysis showed that age, sex, NL and NSA were independent risk factor for the hip fractures.The ROC curve analysis showed that area under curve (AUC) were 0.818, 0.818 and 0.725, respectively. Conclusions: The patients with older age, longer NL and larger NSA might be prone to hip fracture and it was an effective and feasible method to reconstruct and measure the CT data of the proximal femur with Mimics software.

[Epidemiological analysis of hospitalized patients with femoral neck fracture in a first-class hospital of Beijing].

OBJECTIVE: To analyze the clinical parameters of the patients with femoral neck fracture such as general condition, therapy method, hospitalized expense so as to provide more effective management plan for the clinical work. METHODS: The patients with femoral neck fracture above 50 years who received in-patient treatment from 2008 January to 2012 December were admitted into this study. We collected and analyzed the information, such as age, chronic medical disease, therapy method, hospitalized duration and expense and so on. RESULTS: There were 1 794 femoral neck fracture patients above 50 years (male/female=1/2.06) in our hospital in recent 5 years and the annual average rate of increase was 7.3%. The average age of the patients was (69.9±10.7) years and the annual average rate of increase was 0.6%. The chronic medical disease diagnosis ratio was 55.0%. The average waiting time for operation was (6.8±4.2) days and the average hospitalized duration was (12.9±4.9) days which showed downward trend in recent years. The most popular operations were cannulated screw internal fixation (41.8%) and artificial femoral head replacement (34.1%). In the study, 146 cases (7.9%) received nonsurgical treatment which showed downward trend. The average hospitalized expense was (35 075.7±11 343.2) yuan which showed no obvious change in recent years. The cost for the females was more than that for the males. The expense for hemiarthroplasty and total hip arthroplasty increased while that for cannulated screw internal fixation decreased gradually. CONCLUSION: The cannulated screw internal fixation and artificial femoral head replacement were the most important operations for the patients with femoral neck fracture. The number and the average age of the patients were on the rise while the expense showed no obvious change in recent years.

[Clinical features of irritable bowel syndrome with small intestinal bacterial overgrowth and a preliminary study of effectiveness of Rifaximin].

OBJECTIVE: To investigate the prevalence and clinical features of small intestinal bacterial overgrowth (SIBO) in diarrhea-predominant irritable bowel syndrome (IBS-D) patients detected by hydrogen and methane in lactulose breath test (LBT), and to study the effects of rifaximin in IBS-D patients. METHODS: Consecutive patients with IBS-D who met Rome Ⅲ criteria, and gender- and age-matched healthy volunteers were enrolled from March 2015 to January 2016 in Peking University Third Hospital. All the ISB-D patients underwent LBT to detect the prevalence of SIBO. The clinical and LBT features of IBS with SIBO (IBS-P group) and without SIBO (IBS-N group) were analyzed. The effects of rifaximin therapy (0.4 g, twice per day for 4 weeks) in IBS-D patients were evaluated by comparing changes in clinical features and LBT results after treatment. RESULTS: (1) Eighty-four IBS-D patients and 22 healthy controls were enrolled. The prevalence of SIBO in IBS-D patients was 41.67% (35/84), with 27 (77.14%) only hydrogen-positive, 5 (14.29%) methane-positive, and 3 (8.57%) both methane- and hydrogen-positive. (2) The body mass index (BMI) in the IBS-P group was lower than in the IBS-N group [(21.61±0.57) vs (23.44±0.54) kg/m(2,) P<0.05], the maximum stool frequency was also less than in the IBS-N group [(3.85±0.23) vs (4.88±0.35) times/day, P<0.05]. (3) No significant difference was found in oro-cecal transit time (OCTT) among IBS-P, IBS-N and healthy controls. The hydrogen concentration in small intestinal and colonic sections in breath of the IBS-P group was higher than that of both healthy controls and the IBS-N group, while methane concentration in small intestinal and colonic sections (160 min) was higher than that of the IBS-N group (all P<0.05). (4) There was no linear relationship between mean hydrogen and methane concentrations in LBT among the IBS-P, the IBS-N and healthy control groups (all r<0.35, P>0.05). (5) Totally 13 IBS-P patients received rifaximin therapy, in whom the symptoms of abdomen pain, bloating, fecal consistency, stool frequency, and stool satisfactory were significantly improved after treatment (all P<0.05); 8 IBS-N patients received rifaximin therapy, in whom fecal consistency, stool frequency, and satisfactory were significantly improved (all P<0.05). (6) And 5/13 of the IBS-P patients receiving rifaximin presented negative LBT results after rifaximin therapy, with lower hydrogen concentration at all the time points, especially in colonic section (120 min) [(34.54±7.32) ×10(-6) vs (52.23±9.40) ×10(-6,) P<0.05] and lower methane concentration especially in small intestinal section (80 min) [(8.54±0.95) ×10(-6) vs (11.31±0.94) ×10(-6,) P<0.05]. CONCLUSIONS: About 41.67% of the IBS-D patients meeting Rome Ⅲ criteria have SIBO, which can be better screened by combining hydrogen and methane in LBT compared with only hydrogen in LBT. SIBO can affect nutritional status in IBS-D patients. Rifaximin can improve the systematic symptoms of IBS-D patients with SIBO, also reduce hydrogen and methane concentration in breath, while only improving diarrhea in IBS-D patients without SIBO. Some differences in gut microbiota may exist between IBS-D with and without SIBO.

Sub-100nm resolution PSIM by utilizing modified optical vortices with fractional topological charges for precise phase shifting.

We demonstrate an all-optical plasmonic structured illumination microscopy (PSIM) technique. A set of plasmonic standing-wave patterns is excited by amplitude-modified optical vortices (OVs), which have fractional topological charges for precise phase shift of {-2π/3, 0, 2π/3}. A specially designed optical aperture is introduced to modify the OVs in order to improve the uniformity of interference patterns. The imaging results of fluorescent beads reveal a sub-100nm resolving capability in aqueous environment. This PSIM technique as a structure-free, wide-field and super-resolved imaging technique is of great potential for low-cost biological dynamic imaging applications.

A novel missense mutation nt737T>G of JK gene with Jk(a-b-) phenotype in Chinese blood donors.

OBJECTIVES: The aim of this study was to investigate the molecular mechanism of the JK-null phenotype in the Chinese population. BACKGROUND: The Jk(a-b-) phenotype is vanishingly rare and the molecular basis differs between ethnic groups. The information regarding the molecular basis of JK-null alleles in the Chinese population is limited. MATERIALS AND METHODS: Three unrelated Jk(a-b-) phenotype donors were selected from 52 260 randomly blood samples through the urea lysis test and serological analysis. The JK gene-coding regions were amplified by the polymerase chain reaction and the products were sequenced directly. RESULTS: Sequencing results revealed that one sample of JK(*) B alleles carried the well-known Polynesian Jk(a-b-) mutation IVS5-1g>a. Another null allele, also on the JK(*) B background, presented with two heterozygous missense mutation, including nt222C>A(Asn74Lys) in exon 5 and nt896G>A(Gly299Glu) in exon 9. The third null allele carried two heterozygous missense mutations, nt222C>A and a novel allele nt737T>G(Leu246Arg) in exon 8. The family investigation revealed that the proband was JK(*) A(737T>G)/JK(*) B(222C>A). CONCLUSION: The Jk(a-b-) phenotype in the Chinese population shows several different molecular mechanisms. A novel missense mutation nt737T>G of JK gene was found as associated with Jk(a-b-) phenotype.

Suppression of PinX1 resulted in telomere dysfunction and enhanced radiosensitivity in osteosarcoma cell lines.

Telomeres have emerged as a promising and important factor modulating cellular and organism responses to ionizing radiation (IR). Pin2/TRF1 interacting protein X1 (PinX1) is an intrinsic telomerase inhibitor and a putative tumor suppressor gene in human cancers. The aim of this study is to investigate the role PinX1 in osteosarcoma (OS) radioresistance. A telomerase-positive OS cell line Saos-2 and a telomerase-negative OS cell line U2OS were used. PinX1 shRNA lentiviral vetors were constructed and transfected to cells. PinX1 expression was determined by real-time quantitative PCR (qPCR) and Western blotting. Relative telomere length (RTL) was detected by using qPCR. Flow cytometric analysis was used to detect cell cycle and apoptosis. Radiosensitivity was determined by colony formation assay. Data showed that, PinX1 knockdown resulted in telomere shortening, G1 phase arrest, increased apoptosis and enhanced IR sensitivity both in Saos-2 and U2OS cell lines, regardless of telomerase status. Our study concluded that PinX1 could serve as a novel predictor for radiotherapy response to OS patients, and the pathway of PinX1-mediated telomere stability might represent a new target to improve the radiotherapy effect of OS.

Cloning and functional analysis of the promoter of a maize starch synthase III gene (ZmDULL1).

The ZmDULL1 gene encodes a starch synthase and is a determinant of the structure of endosperm starch in maize (Zea mays L.). However, little is known regarding the regulatory mechanism of the ZmDULL1 gene. In this study, we isolated and characterized the ZmDULL1 promoter (PDULL1), which is the 5' flanking region of ZmDULL1 in maize. Sequence analysis showed that several cis-acting elements important for endosperm expression (GCN4_motif and AACA-element) were located within the promoter. A series of PDULL1 deletion derivatives, PDULL1-1-PDULL1-4, from the translation start code (-1676, -1216, -740, and -343) were fused to the ß-glucuronidase (GUS) reporter gene. Each deletion construct was transformed into rice using the Agrobacterium-mediated method, and then GUS activity was measured in transgenic plants. The results showed that PDULL1 was an endosperm-specific promoter. Further analysis showed that the promoter sequence (-343 to -1 base pairs) was sufficient for mediating GUS gene expression in endosperm. These results indicate that the region from -343 to -1 base pairs of PDULL1 is valuable for transgenic rice breeding and genetic engineering studies.

Screening relevant genes of tolerance to low phosphorus in maize using cDNA-amplified fragment length polymorphism.

Soil contains a large amount of phosphorus, but plants cannot absorb most of this phosphorus effectively. Low inorganic phosphorus has been singled out as a major constraint that leads to a perpetually low Zea mays (maize) grain yield. The fundamental approach to solving this problem is to screen new genes of low phosphorous (LP) tolerance. Consequently, the exploration and utilization of LP-tolerant genes are of great significance in plants. The maize inbred line 178 is an inbred LP-tolerant line. In the current study, the expression of this inbred line was induced under the stress of LP conditions. We applied cDNA-amplified fragment length polymorphism to screen LP-tolerant genes and obtained and sequenced 78 differentially expressed gene fragments. Their functions were predicted via bioinformatic analysis. There were no function annotations for 8 differentially expressed fragments. Nine genes exhibited high homology to Arabidopsis thaliana and Oryza sativa genes involved in phosphorus metabolism. This study lays a good foundation for further cloning and verification of the genes involved in phosphorus metabolism in maize.

Overexpression of an endo-1,4-ß-glucanase V gene (EGV) from Trichoderma reesei leads to the accumulation of cellulase activity in transgenic rice.

The ectopic expression of cellulase in biomass can reduce the cost of biofuel conversion. This trait modification technique is highly beneficial for biofuel production. In this study, we isolated an endo-1,4-beta-glucanase gene (EGV) from Trichoderma reesei and inserted this gene downstream of a fragment encoding the signal peptide Apo-SP in a modified pCAMBIA1301 vector to obtain an Apo-SP and AsRed fusion protein. Transient expression of this fusion protein in onion epidermal cells showed that the Apo-SP signal was localized to the plastids. EGV transgenic rice plants that did not carry screening marker genes were obtained through overexpression of the pDTB double T-DNA vector. Western blotting showed that EGV was expressed in the dry straw of T0 generation transgenic rice plants and in fresh leaves of the T1 generation. More importantly, our results also showed that the peptide product of EGV in the transgenic plants folded correctly and was capable of digesting the cellulase substrate CMC. Additionally, cellulase activity remained stable in the straw that had been dried at room temperature for three months. This study presents an important technical approach for the development of transgenic rice straw that has stable cellulase activity and can be used for biofuel conversion.

Effect of temperature on endogenous hormone levels and opposite phyllotaxy in maize leaf primordial.

Newly identified maize (Zea mays) mutants with opposite leaf phyllotaxy are important in the study of the maize crop. Previous studies have revealed the developmental mechanism of opposite phyllotaxy on the physiological, cellular, and molecular levels. However, there have been few reports regarding the effects of changes in endogenous hormone levels in maize leaf primordia under different conditions. We conducted field studies to examine the influence of different environmental factors on leaf primordia differentiation. Our results indicated that compared with other major environmental factors, temperature was significantly positively correlated with the ratio of maize plants with opposite phyllotaxy. We examined endogenous hormone levels in maize at different temperatures using an enzyme-linked immunosorbent assay. The results showed that the ratio of maize plants with opposite phyllotaxy was mainly influenced by the cytokinin/auxin ratio. In addition, at the same temperature, the ratio of cytokinin/auxin in maize with opposite phyllotaxy was significantly higher than that near isogenic lines with alternate phyllotaxy.

Dynamic cosine-Gauss plasmonic beam through phase control.

We carry out an approach to dynamic manipulation of a nondiffracting cosine-Gauss plasmonic beam (CGPB) illuminated with an incident phase modulation within nanostructures by a spatial light modulator (SLM). By changing the hologram addressed on the SLM, dynamic control on the lobe width and the propagating direction of the CGPB is experimentally verified. Finally, we demonstrate an application example of this dynamic CGPB in routing optical signals to multichannel subwavelength wave guides through numerical simulation.