An atypical HLH protein OsLF in rice regulates flowering time and interacts with OsPIL13 and OsPIL15.

In plants, flowering as a crucial developmental event is highly regulated by both genetic programs and environmental signals. Genetic analysis of flowering time mutants is instrumental in dissecting the regulatory pathways of flowering induction. In this study, we isolated the OsLF gene by its association with the T-DNA insertion in the rice late flowering mutant named A654. The OsLF gene encodes an atypical HLH protein composed of 419 amino acids (aa). Overexpression of the OsLF gene in wild type rice recapitulated the late flowering phenotype of A654, indicating that the OsLF gene negatively regulates flowering. Flowering genes downstream of OsPRR1 such as OsGI and Hd1 were down regulated in the A654 mutant. Yeast two hybrid and colocalization assays revealed that OsLF interacts strongly with OsPIL13 and OsPIL15 that are potentially involved in light signaling. In addition, OsPIL13 and OsPIL15 colocalize with OsPRR1, an ortholog of the Arabidopsis APRR1 gene that controls photoperiodic flowering response through clock function. Together, these results suggest that overexpression of OsLF might repress expression of OsGI and Hd1 by competing with OsPRR1 in interacting with OsPIL13 and OsPIL15 and thus induce late flowering.

[Effect of prone or spine position on mechanically ventilated neonates after cardiac surgery with acute lung injury].

OBJECTIVE: To compare the efficacy and safety ventilated with pressure support ventilation (PSV) or neurally adjusted ventilatory assist (NAVA) in neonates undergoing open-heart surgery with acute lung injury (ALI) in spine and prone positions. METHODS: Fifteen neonates with a mean age of (15 +/- 9) days and a mean weight of (3.5 +/- 0.6) kg underwent open-heart surgery with ALI from July to December in 2009 were enrolled in this study. After hemodynamic stabilization ventilated with pressure regulated volume control (PRVC-base), all cases were ventilated with PSV and NAVA both in spine (SP) and prone (PP) positions for 60 minutes in a randomized crossover trial respectively. The hemodynamics, blood gas analysis, airway pressure, electrical activity of diaphragm (EAdi) and asynchrony index (AI) during every mode were recorded. RESULTS: The heart rate, systolic blood pressure and central venous pressure were stable in every mode. The peak inspiratory pressure and mean airway pressure in every mode had no significant difference but were significantly lower than in PRVC-base either in spine or prone position. The respiratory rate in PSV and NAVA with prone position was more rapid than in spine position and in PRVC-base (P < 0.05). But there was no significant difference in minute ventilation (MV) for each mode. The oxygenation index was higher in NAVA or PSV in both positions versus PRVC-base [(200 +/- 60) mm Hg in PRVC-base, (272 +/- 76) mm Hg in PSV-SP, (308 +/- 90) mm Hg in PSV-PP, (347 +/- 84) mm Hg in NAVA-SP and (365 +/- 87) mm Hg in NAVA-PP respectively, P < 0.01]. The oxygenation index was significantly higher in NAVA-PP than in PSV-SP (P < 0.05) while PaCO(2) was in normal range and had no significant difference for any mode. The minimal EAdi in NAVA-PP was significant lower than that in PSV-SP [(0.2 +/- 0.1) microV vs (0.5 +/- 0.2) microV, P < 0.05]. The AI of NAVA either in spine or in prone position was 0. It was significantly lower than that in PSV-SP [(21.5 +/- 4.8)%, P < 0.01] and PSV-PP [(22.4 +/- 3.4)%, P < 0.01]. CONCLUSION: Especially in a prone position, NAVA demonstrates a better synchrony in ALI neonates after cardiac surgery. It helps to provide a better oxygenation for the patients.

Overexpression of ACL1 (abaxially curled leaf 1) increased Bulliform cells and induced Abaxial curling of leaf blades in rice.

Understanding the genetic mechanism underlying rice leaf-shape development is crucial for optimizing rice configuration and achieving high yields; however, little is known about leaf abaxial curling. We isolated a rice transferred DNA (T-DNA) insertion mutant, BY240, which exhibited an abaxial leaf curling phenotype that co-segregated with the inserted T-DNA. The T-DNA was inserted in the promoter of a novel gene, ACL1 (Abaxially Curled Leaf 1), and led to overexpression of this gene in BY240. Overexpression of ACL1 in wild-type rice also resulted in abaxial leaf curling. ACL1 encodes a protein of 116 amino acids with no known conserved functional domains. Overexpression of ACL2, the only homolog of ACL1 in rice, also induced abaxial leaf curling. RT-PCR analysis revealed high expressions of ACLs in leaf sheaths and leaf blades, suggesting a role for these genes in leaf development. In situ hybridization revealed non-tissue-specific expression of the ACLs in the shoot apical meristem, leaf primordium, and young leaf. Histological analysis showed increased number and exaggeration of bulliform cells and expansion of epidermal cells in the leaves of BY240, which caused developmental discoordination of the abaxial and adaxial sides, resulting in abaxially curled leaves. These results revealed an important mechanism in rice leaf development and provided the genetic basis for agricultural improvement.

[Application of neurally adjusted ventilatory assist in infants who underwent cardiac surgery for congenital heart disease].

OBJECTIVE: Neurally adjusted ventilatory assist (NAVA) is a new mode of mechanical ventilation that delivers ventilatory assist in proportion to neural effort. This study aimed to compare the hemodynamic safety, oxygenation and gas exchange effects ventilated with NAVA and with pressure support ventilation (PSV) in infants who underwent open-heart surgery. METHODS: Twenty-one infants who underwent open-heart surgery for congenital heart disease (mean age 2.9+/- 2.1 months and mean weight 4.2+/- 1.4 kg) were enrolled. They were ventilated with PSV and NAVA for 60 minutes respectively in a randomized order. The hemodynamic, oxygenation and gas exchange effects produced by the two ventilation modes were compared. RESULTS: Three cases failed to shift to NAVA because of the bilateral diaphragmatic paralysis after operation. In the other 18 cases, there were no significant differences in the heart rate (HR), systolic blood pressure (BPs) and central venous pressure (CVP) in the two ventilation modes. The PaO2/FiO2 (P/F) ratio in NAVA was slightly higher than in PSV, but there was no statistical difference. PaCO2 did not show significant differences in the two modes. The peak inspiratory pressure (PIP) and electrical activity of the diaphragm (EAdi) in NAVA were significantly lower than in PSV. The EAdi signal after extubation was higher in infants who needed reintubation or intervention of noninvasive mechanical ventilation than in those who were extubated successfully (30.0+/- 8.4 microV vs 11.1+/- 3.6 microV; P<0.01). CONCLUSIONS: As the first study of application of NAVA in infants in China, this study shows that NAVA has the same homodynamic effects as PSV. However the PIP for maintaining the same level of PaCO2 in NAVA is significantly lower than that in the traditional PSV. Monitoring the EAdi signal after extubation may show the risks of reintubation or intervention of noninvasive mechanical ventilation.

The expression pattern of a rice proteinase inhibitor gene OsPI8-1 implies its role in plant development.

A rice proteinase inhibitor (PI) gene OsPI8-1 was identified. Belonging to the potato inhibitor I family, this gene contains a 201bp coding region with no introns and encodes a deduced protein of 66 amino acids which holds a PI domain. There are two uniform gene copies, OsPI8-1a and OsPI8-1b, with direct-repeat arrangement and an interval span of 13 kb on rice chromosome 8, corresponding to the site of BAC clone P0528B09 (Accession No. AP004703). Reverse transcription polymerase chain reaction (RT-PCR) assays showed that both OsPI8-1a and OsPI8-1b can be expressed in wild-type 'Zhonghua No.11'. To investigate the physiological functions of OsPI8-1 in plant development, we analyzed the expression patterns of the reporter gene beta-glucuronidase (GUS) driven by OsPI8-1 promoter at different developmental stages and tissues. It was demonstrated that no GUS signals were detected in the roots. Despite that very high GUS expression was examined in the shoot apical meristem, no detectable GUS activity in the developmental domains of leaf primordium was observed. OsPI8-1 promoter showed an obvious wound-induced response in mature leaves. Little GUS activity was detected in young nodes and internodes at the seedling stage, but active GUS expression was observed near the nodes on mature culms. In the developing stage of the anther, GUS signal was specifically located in the middle layer and the endothecium between the epidermis and tapetum. In the germinating seed, GUS expression was gradually accumulated in the side of scutellar epithelium close to the embryo. These tissue-specific accumulations suggested that OsPI8-1 has multiple endogenous roles on developmental regulation. In this report, the inhibitor function of OsPI8-1 to proteolytic enzymes and the potential influence of their poise on plant development (such as seed germination, tapetum degeneration, programmed cell death, etc.) were discussed.

Overexpression of transcription factor OsLFL1 delays flowering time in Oryza sativa.

Flowering time is regulated by genetic programs and environment signals in plants. Genetic analysis of flowering time mutants is instrumental in dissecting the regulatory pathways of flower induction. Genotype W378 is a rice (Oryza sativa) late-flowering mutant selected from our collections of T-DNA insertion line. The T-DNA flanking gene in mutant W378 codes OsLFL1 (O. sativa LEC2 and FUSCA3 Like 1), a putative B3 DNA-binding domain-containing transcription factor. In wild-type rice OsLFL1 is expressed exclusively in spikes and young embryos, while in mutant W378 it is ectopically expressed. Introduction of OsLFL1-RNAi into mutant W378 successfully down-regulated OsLFL1 expression and restored flowering to almost normal time, indicating that overexpression of OsLFL1 confers late flowering for mutant W378. The flowering-promoting gene Ehd1 and its downstream genes are all down-regulated in W378. Thus, overexpression of OsLFL1 might delay the flowering of W378 by repressing the expression of Ehd1.

Seven years' experience of pediatric cardiopulmonary bypass: 8685 cases in Shanghai Children's Medical Center.

Herein we report our 7-year-experience of cardiopulmonary bypass. Between April 1, 1999, and December 31, 2005, 8685 children with congenital heart disease underwent cardiopulmonary bypass in Shanghai Children's Medical Center. The number of cases increased every year, and the number of patients younger than 1 year or weighing <10 kg also increased. Different bypass technology was adapted according to the operation. Roller pumps were used for most of the patients. Crystal cardioplegia (St. Thomas II) was used until blood cardioplegia was introduced in 2003. Ultrafiltrators were set up for infants weighing <10 kg. Mortality rates per year ranged from 1.81% to 3.70%. The most frequent complication was low cardiac output, about 12% in recent years. Arrhythmia, infection, and lung complications were the next three most frequent problems after surgery.

[Mapping of a new resistance gene to bacterial blight in rice line introgressed from Oryza officinalis].

Rice line 'B5', which was derived from the wild rice Oryza officinalis Wall ex Watt through introgression, has been proved to be high resistant to brown planthopper, whitebacked planthopper and bacterial blight (Xanthomonas oryzae pv. oryzae). In this study, the resistance to bacterial blight of 187 recombinant inbred lines (RILs) from a cross between ' B5' and 'Minghui63' were evaluated and RFLP markers linked to the resistance gene were identified by bulked segregant analysis. Analysis of the molecular marker linkage map and the data of the lesion length of RILs located the resistant gene within a 1. 3 cM region flanked by RFLP markers C904 and R596 on chromosome 1. This locus contributed to 52.96% of the phenotypic variance of resistance in the population, and is considered to be a new locus as compared with other resistant genes to bacterial blight that have been reported. We tentatively designate this gene as Xa29(t). This newly tagged gene introgressed from wild rice is valuable to molecular marker-assisted selection for multiple resistant materials in rice breeding programme. Furthermore, it provides information for cloning the resistant gene Xa29(t) in rice.

[Arterial switch operation for transposition of the great arteries and double outlet of right ventricle with subpulmonary ventricular septum defect].

OBJECTIVE: To summarize the clinical experience on the arterial switch operation for complex congenital heart disease in recent 3 years in our hospital. METHODS: Sixty-one patients with complex congenital heart disease received by arterial switch operation from Jan 2000 to May 2003. There were 26 patients with transposition of the great arteries and intact ventricular septum (TGA-IVS), 19 patients with transposition of the great arteries and ventricular septal defect (TGA-VSD) and 16 patients with double outlet of right ventricle with subpulmonary ventricular septum defect (Taussig-Bing). RESULTS: There were 2 death among TGA-IVS cases, 4 deaths among TGA-VSD cases and 4 deaths among Taussig-Bing cases. The total operative mortality was 16%. All patients were followed up 3 months to 3 years. In all patients, the cyanosis disappeared and the physical activities increased obviously. One patients with Taussig-Bing keep moderate mitral valve reflux unchanged, 2 patients with TGA had pulmonary and aortic supra-valve stenosis with 40 mmHg pressure gradient. One patient with subpulmonary stenosis and residual VSD was re-operated 3 months later. All survivor had good heart function. CONCLUSIONS: The effect of arterial switch operation on the treatment of TGA was well accepted in this study. The procedure used in treatment on Taussig-Bing can prevent pulmonary obstruction and avoid the complication of left ventricular outflow tract obstruction caused by intraventricular repair.