Pulmonary Epstein-Barr virus-associated smooth muscle tumor after kidney transplantation: two case reports with review of differential diagnosis.

Pulmonary nodules are a common complication in solid organ transplant recipients, and may have various underlying causes, with Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) being one of them. Given the rarity of this entity, we describe the diagnosis and therapeutic interventions for post-transplant EBV-SMT in two individuals. Both cases involved female patients who were diagnosed with multiple pulmonary nodules 60 months and 116 months, respectively, after receiving living-related kidney transplantation. Pathological examination revealed a spindle cell tumor, with immunophenotype and EBV in situ hybridization supporting the diagnosis of EBV-SMT. After diagnosis, these two patients underwent intervention by decreasing their intake of immunosuppressants. As of the latest follow-up, the patients' lesion size remained stable, and their overall condition was favorable. We also reviewed literature about the morphological and molecular pathological features of EBV-SMT and highlighted the diagnosis and differential diagnosis of pulmonary spindle cell lesions especially in the setting of immunosuppression.

[Effects of gender on treatment strategies for elderly patients with acute coronary syndrome].

OBJECTIVE: To explore the effects of gender on treatment strategies for elderly patients with acute coronary syndrome (ACS). METHODS: March 2009 to March 2012, consecutive 619 aged ACS patients undergoing coronary angiography (CA) were screened at our hospital. There were 273 females and 346 males. Risk factors, ACS diagnosis, CA results, treatments and prognosis were compared between female and male groups. RESULTS: The risk factors of body mass index, stroke history, smoking history, hemoglobin (Hb), serum cholesterol (TC), low density lipoprotein (LDL-C) and blood uric acid (UA) levels were significantly lower in female group than those in male group (P < 0.05). The morbidity of diabetes in female group was obviously higher than that in male group (27.8% vs 18.5%, P < 0.05). The prevalence of myocardial infarction history, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) history in male group were significantly greater than that in female group (48.0% vs 39.9%, P < 0.05; 30.6% vs 22.3%, P < 0.05; 19.9% vs 10.3%, P < 0.01). The rate of combined multiple risk factors (3 or higher) increased significantly in female group (41.8% vs 29.8%, P < 0.05). The incidence of unstable angina pectoris (UAP) and non-ST segment elevation myocardial infarction (NSTEMI) in female group was greater, but there was no statistical significance. The rate of 3-vessel and calcification lesions in female group was significantly elevated compared with male group (36.26% vs 28.61%, P < 0.05). Regarding the choice of treatment strategy, conservative treatment was common in females, but there was no statistical significance between them. PCI, emergency PCI and selective CABG operation were performed more frequently in female group compared with male group (26.0% vs 14.2%, P < 0.01; 14.7% vs 6.6%, P < 0.01; 19.1% vs 7.7%, P < 0.01). The prognosis had no statistical significance between two groups. CONCLUSION: The treatment strategies have certain limitations for female ACS patients. And an more aggressive treatment should be offered to improve the prognosis.

Indole Alkaloids from Alocasia macrorrhiza.

Five new indole alkaloids, alocasins A-E (3-7), together with known hyrtiosin B (1) and hyrtiosulawesin (2) were isolated from Alocasia macrorrhiza (L.) SCHOTT; their structures were elucidated on the basis of spectroscopic data. Compounds 1-7 were in vitro tested for cytostatic activity on human throat cancer (Hep-2), human hepatocarcinoma (Hep-G2), and human nasopharyngeal carcinoma epithelial (CNE) cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method; compounds 2, 3, 6 and 7 showed mild antiproliferative activity against Hep-2 and Hep-G2 whereas compounds 2 and 4 showed gentle antiproliferative activity against CNE.

[Construction of miRNA expression vector dual-targeting on HIF-1α/survivin genes and its effects on proliferation of pancreatic cancer Panc-1 cell line].

OBJECTIVE: To design and construct miRNA expression vector dual-targeting on HIF-1α and survivin genes and to investigate its effects on proliferation of human pancreatic cancer cells. METHODS: The specific pre-miRNA single strand DNA oligos for HIF-1 α and survivin genes were designed and synthesized, then via annealing and ligating with pcDNA6.2-GW/EmGFP-miR plasmids in order, two kinds (eight in total) of miRNA expression vectors for HIF-1α and survivin genes were constructed. The vectors, which were most effective to knockdown target genes, were screened with real-time RT-PCR and combined by chaining technology to construct dual-targeting plasmid. The recombined dual-targeting plasmid, mono-targeting plasmids and negative plasmid were transfected into Panc-1 cells, the suppression effect on two genes was identified by real-time RT-PCR, Western blot and MTT assays. RESULTS: The miRNA expression plasmids anti-H, anti-S and anti-H+S were successfully constructed by identification of sequencing analysis, and they were able to effectively inhibit the target genes expressing. MTT assays showed that the inhibition effect of dual-targeting vector anti-H+S was higher than that of mono-targeting vectors anti-H and anti-S 72 h after transfection (P<0.05). CONCLUSION: The effective miRNA expression vector dual-targeting on HIF-1α and survivin genes has been successfully constructed. The inhibition effect on proliferation of pancreatic cancer Panc-1 cells by dual-targeting plasmid was higher than that by mono-target plasmids.

Efficacy and safety of long-term transcutaneous electroacupuncture versus sham transcutaneous electroacupuncture for delayed gastric emptying after distal gastrectomy: study protocol for a randomized, patient-assessor blinded, controlled trial.

BACKGROUND: Delayed gastric emptying (DGE) after distal gastrectomy impacts patients' nutritional status and quality of life. The current treatments of DGE seem unsatisfactory or need invasive interventions. It is unknown whether transcutaneous electroacupuncture (TEA) is effective in treating DGE. METHODS: A total of 90 eligible participants who underwent distal gastrectomy will be randomly allocated to either the TEA group (n = 60) or the sham transcutaneous electroacupuncture (sham-TEA) group (n = 30). Each participant will receive TEA on the bilateral acupoints of Zusanli (ST36) and Neiguan (PC6) for 4 weeks. The primary outcomes will be the residual rates of radioactivity in the stomach by gastric scintigraphy and total response rates. The secondary outcomes will be endoscopic features, autonomic function, nutritional and psychological status, serum examination, and quality of life (QoL). The adverse events will also be reported. The patients will be followed up 1 year after the treatment. DISCUSSION: The findings of this randomized trial will provide high-quality evidence regarding the efficacy and safety of long-term TEA for treating DGE after distal gastrectomy. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000033965. Registered on 20 June 2020.

Drought-induced site-specific DNA methylation and its association with drought tolerance in rice (Oryza sativa L.).

An indica pyramiding line, DK151, and its recurrent parent, IR64, were evaluated under drought stress and non-stress conditions for three consecutive seasons. DK151 showed significantly improved tolerance to drought. The DNA methylation changes in DK151 and IR64 under drought stress and subsequent recovery were assessed using methylation-sensitive amplified polymorphism analysis. Our results indicate that drought-induced genome-wide DNA methylation changes accounted for ∼12.1% of the total site-specific methylation differences in the rice genome. This drought-induced DNA methylation pattern showed three interesting properties. The most important one was its genotypic specificity reflected by large differences in the detected DNA methylation/demethylation sites between DK151 and IR64, which result from introgressed genomic fragments in DK151. Second, most drought-induced methylation/demethylation sites were of two major types distinguished by their reversibility, including 70% of the sites at which drought-induced epigenetic changes were reversed to their original status after recovery, and 29% of sites at which the drought-induced DNA demethylation/methylation changes remain even after recovery. Third, the drought-induced DNA methylation alteration showed a significant level of developmental and tissue specificity. Together, these properties are expected to have contributed greatly to rice response and adaptation to drought stress. Thus, induced epigenetic changes in rice genome can be considered as a very important regulatory mechanism for rice plants to adapt to drought and possibly other environmental stresses.

[Binding pancreatic duct to mucosa anastomosis].

OBJECTIVE: To study the feasibility of binding pancreatic duct to mucosa anastomosis (BDM)-a complementary procedure to both binding pancreaticojejunostomy and binding pancreaticogastrostomy. METHODS: (1) Animal experimental study:gastrostomy and jejunostomy were performed on six adult New Zealand rabbits. The gastrostomy and jejunostomy shared a same stent (rubber urethral catheter, silicone tube or plastic infusion tube). Both ends of the stent were placed in gastric and enteric cavity. Purse-string suture was performed around the stent before the jejunum and the stomach were brought together for fixation by few stitches. And to observe whether the purse-string suture around a plastic tube, rubber tube or silicon tube inserted into jejunum and/or stomach can prevent leaking out of the jejunal or gastric content to cause peritonitis. (2) Clinically 7 patients were performed with BDM anastomosis. The procedure was consisted of five steps: preparation of the pancreatic stump;preparation of the jejunum; preparation of the fixing sutures between the pancreatic stump and the jejunum; implementation of the anastomosis; lastly, fixation of the jejunum beside the pancreas stump. Post-operative periodic examination of the blood amylase and the amylase in the abdominal drainage. Pancreatic fistula was classified in to two categories: parenchymal fistula (pancreatic cut surface fistula) and anastomotic leakage. RESULTS: Animal experiment did not show any leakage around the plastic tube or silicon tube inserted into jejunum and(or) stomach. There was no anastomotic leak in all the patients. There was transient increase of amylase in two cases, but the volume of drainage did not exceed 50 ml/d and the recovery of the patients was not affected. CONCLUSIONS: BDM is a simple, safe and easy procedure to perform. It provides to the surgeons with a new option in different situations to achieve the most ideal surgical result.

Genome-wide gene responses in a transgenic rice line carrying the maize resistance gene Rxo1 to the rice bacterial streak pathogen, Xanthomonas oryzae pv. oryzicola.

BACKGROUND: Non-host resistance in rice to its bacterial pathogen, Xanthomonas oryzae pv. oryzicola (Xoc), mediated by a maize NBS-LRR type R gene, Rxo1 shows a typical hypersensitive reaction (HR) phenotype, but the molecular mechanism(s) underlying this type of non-host resistance remain largely unknown. RESULTS: A microarray experiment was performed to reveal the molecular mechanisms underlying HR of rice to Xoc mediated by Rxo1 using a pair of transgenic and non-transgenic rice lines. Our results indicated that Rxo1 appeared to function in the very early step of the interaction between rice and Xoc, and could specifically activate large numbers of genes involved in signaling pathways leading to HR and some basal defensive pathways such as SA and ET pathways. In the former case, Rxo1 appeared to differ from the typical host R genes in that it could lead to HR without activating NDR1. In the latter cases, Rxo1 was able to induce a unique group of WRKY TF genes and a large set of genes encoding PPR and RRM proteins that share the same G-box in their promoter regions with possible functions in post-transcriptional regulation. CONCLUSIONS: In conclusion, Rxo1, like most host R genes, was able to trigger HR against Xoc in the heterologous rice plants by activating multiple defensive pathways related to HR, providing useful information on the evolution of plant resistance genes. Maize non-host resistance gene Rxo1 could trigger the pathogen-specific HR in heterologous rice, and ultimately leading to a localized programmed cell death which exhibits the characteristics consistent with those mediated by host resistance genes, but a number of genes encoding pentatricopeptide repeat and RNA recognition motif protein were found specifically up-regulated in the Rxo1 mediated disease resistance. These results add to our understanding the evolution of plant resistance genes.

[Laparoscopic ultrasonography in laparoscopic hepatectomy: experience with 22 cases].

OBJECTIVE: To assess the value of laparoscopic ultrasonography in laparoscopic hepatectomy. METHODS: Twenty-two patients with liver diseases underwent laparoscopic ultrasonography. A 10 mm 7.5/10 MHz linear, side viewing laparoscopic ultrasonography probe was used intra-operatively to examine the convergence of intrahepatic biliary ducts and blood vessels, confirm and correct the resection line, guide the laparoscopic resection, examine the tumor margin, and discover the residue of calculi. RESULTS: One additional tumor was detected in one primary liver tumor case during the laparoscopic hepatectomy. Laparoscopic hepatectomy was accomplished successfully in 21 patients one of which had to be transferred to laparotomy due to severe liver cirrhosis and uncontrollable bleeding. The average operation time was 157 min with the average examining and guiding time of 14 min. The intra-operative bleeding amount was 520 ml. No calculus and tumor residue were found. One case of post-operative liver wound bile leakage and one case of subphrenic hydrops were found and they both recovered after drainage. CONCLUSION: Intra-operative laparoscopic ultrasonography helps evaluate the entire liver and decide the resection line accurately. Under its guiding the laparoscopic hepatectomy can be performed smoothly.

Application of Laparoscopic Gastrectomy in Obese Patients (BMI≥30 kg/m2) with Gastric Cancer: A Comparison With Open Gastrectomy Regarding Short-term Outcomes.

OBJECTIVE: Few studies have compared the surgical outcomes of laparoscopic (LG) and open (OG) gastrectomy in obese patients (BMI≥30 kg/m) with gastric cancer. The current study aimed to investigate the short-term outcomes of LG in this group of patients. METHODS: A total of 33 LG cases and 23 OG cases (BMI≥30 kg/m) were identified from our gastric cancer database. Clinicopathologic features, operative details, laboratory examination, and postoperative outcomes were compared between both groups. Regression analysis was used to determine the effects of BMI on intraoperative outcomes. RESULTS: The 2 groups had comparable clinicopathologic characteristics. LG was associated with significantly lesser blood loss, whereas both also groups had a similar operative time, and number of harvested lymph nodes. However, regression analysis indicated that increased BMI affected the operative time and blood loss in patients that underwent OG but had little effect on patients who received LG. The elevation of inflammatory factors (WBC, CRP) was lower in LG than in OG, postoperatively. Postoperative hepatic (alanine aminotransferase, total bilirubin, albumin) and renal (creatinine, blood urea nitrogen) functions in the LG group were not worse than in the OG group. The time to first flatus, initiation of diet, hospitalization, and postoperative complications seemed superior in LG than in OG, but these differences were not statistically significant. CONCLUSION: LG can be safely performed in obese gastric cancer patients. Compared with conventional OG, LG is less invasive and is characterized by less blood loss and milder surgical trauma. LG is also less adversely affected by increased BMI.

[Study on the quality of life after pancreaticoduodenectomy].

OBJECTIVE: To evaluate the quality of life (QOL) of the patients who received pancreaticoduodenectomy (PD) and work out their long term therapy agents. METHODS: QOL of 18 cases who received PD (group PD) and 18 cases received laparoscopic cholecystectomy (LC) (group LC) in the same days was determined by symptoms questionnaire and Chinese version SF-36 QOL questionnaire from Jan 2002 to Dec 2003 in Sir Run Run Shaw Hospital. RESULTS: Compared with group LC, the total QOL score and physical health score of group PD didn't have significant decrease. But the mental health score of group PD was lower than group LC (P < 0.05). Eight different scales of SF-36 questionnaire showed that the score in physical functioning, role-physical, bodily pain, general health, social functioning of group PD was lower than that of group LC. The score in vitality, role-emotional and mental health of group PD was the same as the group LC. According to the symptoms questionnaire, the patient diarrhea and recurrence had obvious influence on PH score. The patient weight loss and unemployment had obvious influence on MH2 score. CONCLUSIONS: The QQL of patients received PD didn't have decreased. Their total score of SF-36 QQL was close to the patients who received LC. But the mental health score of group PD was lower than group LC. Weight loss, unemployment, recurrence and chronic pancreatic diarrhea may be infect the Quality of life after PD.

[Clinical evaluation of laparoscopic radical resection of colon cancer].

OBJECTIVE: To investigate the clinical effect of laparoscopic radical resection of colon cancer. METHODS: Patients with colon cancer who underwent radical resection during January 2000 to January 2004 in Sir Run Run Shaw Hospital (Medical College of Zhejiang University) were divided into open and laparoscopic groups for a non-randomized case-control study. All the patients were followed up and their clinical and pathological results were compared. RESULTS: No difference was seen between the two groups on the patients' age, gender, lymph node numbers and Dukes staging. The laparoscopic group had a longer mean operation time [(182 +/- 62) min vs (141 +/- 37) min] and shorter hospital stay [(5.3 +/- 1.9) d vs (8.2 +/- 1.2) d] than the open group. All surgical margins were pathological negative. Post-operation follow up was 12-18 months (mean 21 months). No incision recurrence was found in neither group. As far the local recurrence and distal metastasis rate were similar in both groups. CONCLUSIONS: Laparoscopic radical resection of colon cancer has minimal invasion and shorter recuperation than open procedure, the radicalness and either local recurrence or distal metastasis rate after surgery are similar when compared with open group.

[Laparoscopic distal pancreatectomy with preservation of the spleen].

OBJECTIVE: To summarize the experience of laparoscopic distal pancreatectomy with preservation of the spleen. METHODS: From Nov 2003 to Dec 2004, 2 patients with cystic lesions in the body and tail of the pancreas underwent laparoscopic distal pancreatectomy with preservation of the spleen. RESULTS: Both of the operations were successful with the operative time of 220 min and 190 min respectively, and the blood loss were 450 ml and 350 ml. There was no postoperative complication and the pathological diagnosis was pancreatic serous cystadenoma. Both patients' symptom disappeared after operation without recurrence during the follow-up of 18 and 5 months. CONCLUSION: Laparoscopic distal pancreatectomy with preservation of the spleen is safe and feasible for the management of benign tumor in the body and tail of pancreas with the advantages of reduced injury, earlier recovery and less complication.

[Laparoscopic resection of true pancreatic cyst: report of 5 cases].

OBJECTIVE: To summarize the experience in laparoscopic resection of true pancreatic cyst. METHODS: Five patients with true pancreatic cyst, including 1 case of pancreatic head cyst and 4 cases of distal pancreatic cyst, underwent laparoscopic resection. Among them one case with pancreatic head cyst and 4 cases of distal pancreatic cyst underwent simple laparoscopic cyst resection and one case of distal pancreatic cyst underwent laparoscopic distal pancreatectomy with resection of the spleen. The curative effects were evaluated. A follow-up lasting 2 approximately 33 months was conducted. RESULTS: All operations were successful with intraoperative blood loss of 50 to 150 ml. The patients could get up and move about 6 hours after the operation and were recovered and discharged 4 to 6 days later. Follow-up showed that all symptoms disappeared and no recurrence of cyst occurred. CONCLUSION: Laparoscopic resection of true pancreatic cyst is feasible with the advantages of reduced injury and earlier recovery.

[The measurement of pre-binding and post-binding tolerance pressure in binding pancreaticojejunostomy].

OBJECTIVE: To evaluate the superiority of binding pancreaticojejunostomy (BPJ) and the appropriate degree of tightness of binding from the view of tolerance pressure of the anastomotic stoma. METHODS: The clinical data of 24 patients with diseases of head of pancreas and duodenum who underwent binding pancreaticojejunostomy were analyzed. The tolerance pressure at the anastomotic stoma was measured before and after the binding. RESULTS: The pre-binding tolerance pressure at the anastomotic stoma ranged from 28 cm H2O to 65 cm H2O, with a median of 44 cm H2O. The post-binding tolerance pressure at the anastomotic stoma ranged from 75 cm H2O to 90 cm H2O, with a mean of 85 cm H2O, significantly higher than those before binding (P < 0.01). CONCLUSION: Binding greatly increases the tolerance pressure at the anastomotic stoma. The tolerance pressure adopted is appropriate.

Pancreatic solid cystic desmoid tumor: case report and literature review.

Desmoid tumors (DTs) are nonmetastatic, locally aggressive neoplasms with a high rate of postoperative recurrence. Pancreatic DTs are especially rare; only a few cases have been reported to date. This paper describes a case of a sporadic cystic DT of the pancreas managed successfully with central pancreatectomy, with no signs of recurrence 40 mo after surgery. According to the literature, this is the first reported case in China of a pancreatic DT presenting as a solid cystic lesion, as well as the first pancreatic DT managed with central pancreatectomy and pancreaticogastrostomy. We report the case for its rarity and emphasize disease management by concerted application of clinical, pathological, radiological and immunohistochemical analyses.

Sutureless choledochoduodenostomy with an intraluminal degradable stent in dog model.

BACKGROUND: It is difficult and time-consuming for carrying out conventional hand-sewn bilioenteric anastomosis, especially for small bile duct anastomosis and laparoscopic procedure. In order to simplify it, we have developed a novel procedure of sutureless bilioenteric anastomosis with an intraluminal degradable stent. This study aimed to evaluate the feasibility and safety of this technique with cholangioduodenostomy in dog model. METHODS: A patent intraluminal degradable stent tube for sutureless choledochoduodenostomy in dog model was made with polylactic acid in diameter of 3 mm or 4 mm. Thirty-eight dogs were randomly divided into to a stent group (SG, n = 20) and a control group (CG, n = 18). Dogs in the SG underwent sutureless choledochoduodenostomy with intraluminal stent, while the CG underwent conventional choledochoduodenostomy (single layer discontinuous anastomosis with absorbable suture). Dogs of each group were divided into 4 subgroups according to time of death (1, 3, 6, and 12 months postoperatively) to evaluate the healing of anastomosis. Operation time, intraoperative tolerance pressure of anastomosis, rate of postoperative bile leakage, bursting pressure of anastomosis were compared between the two groups. Anastomosis tissue was observed afterwards by pathology evaluation, hydroxyproline content, serum bilirubin, liver enzyme level and magnetic resonance cholangio-pancreatography (MRCP) to assess the stricture. RESULTS: All procedures were completed successfully. The surgical time of the SG was significantly less than the CG (SG: (19.2 ± 4.3) minutes, vs. CG: (29.2 ± 7.1) minutes, P = 0.000). One bile leakage was occurred in either group. No significant difference of intraoperative tolerance pressure of anastomosis, rate of bile leakage and postoperative bursting pressure of anastomosis, anastomotic stricture, hydroxyproline content, serum bilirubin and liver enzyme level was found between the two groups. MRCP showed no anastomosis stricture and obstruction during months of follow-up. CONCLUSION: The technique of sutureless choledochoduodenostomy with a degradable intraluminal stent is feasible and a safe procedure in this dog model.

Identification of functional candidate genes for drought tolerance in rice.

Drought tolerance (DT) in rice is known to be controlled by many quantitative trait loci (QTLs) and involved differential expression of large numbers of genes, but linking QTLs with their underlying genes remains the most challenging issue in plant molecular biology. To shed some light on this issue, differential gene expression in response to PEG simulated drought in 3 unique genetic materials (a lowland rice, IR64 and its derived line, PD86 which has 11 introgressed DT QTLs, and a upland rice IRAT109) was investigated using a PCR-based subtractive hybridization strategy. More than 300 unique subtracted cDNA sequences, covering genes of diverse cellular activities and functions, were identified and confirmed by semi-quantitative and quantitative RT-PCR. Detailed bioinformatics analyses of the data revealed two interesting results. First, the levels and mechanisms of DT of the three rice lines were associated with the number and types of differentially expressed genes, suggesting different DT mechanisms in rice are controlled by different sets of genes and different metabolic pathways, and most differentially expressed genes under drought were able to contribute to DT. Second, there appeared a high correspondence in genomic location between DT QTLs and clusters of differentially expressed genes in rice, suggesting some DT QTLs may represent clusters of co-regulated and functionally related genes. Thus, differential gene expression analyses using genetically characterized materials can provide additional insights into the molecular basis of QTLs and convergent evidence to shortlist the candidate genes for target QTLs.

Genome-wide introgression lines and their use in genetic and molecular dissection of complex phenotypes in rice (Oryza sativa L.).

Tremendous efforts have been taken worldwide to develop genome-wide genetic stocks for rice functional genomic (FG) research since the rice genome was completely sequenced. To facilitate FG research of complex polygenic phenotypes in rice, we report the development of over 20,000 introgression lines (ILs) in three elite rice genetic backgrounds for a wide range of complex traits, including resistances/tolerances to many biotic and abiotic stresses, morpho-agronomic traits, physiological traits, etc., by selective introgression. ILs within each genetic background are phenotypically similar to their recurrent parent but each carries one or a few traits introgressed from a known donor. Together, these ILs contain a significant portion of loci affecting the selected complex phenotypes at which allelic diversity exists in the primary gene pool of rice. A forward genetics strategy was proposed and demonstrated with examples on how to use these ILs for large-scale FG research. Complementary to the genome-wide insertional mutants, these ILs opens a new way for highly efficient discovery, candidate gene identification and cloning of important QTLs for specific phenotypes based on convergent evidence from QTL position, expression profiling, functional and molecular diversity analyses of candidate genes, highlights the importance of genetic networks underlying complex phenotypes in rice that may ultimately lead to more complete understanding of the genetic and molecular bases of quantitative trait variation in rice.