Observation of a Strongly Isospin-Mixed Doublet in ^{26}Si via β-Delayed Two-Proton Decay of ^{26}P

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

Large Isospin Asymmetry in ^{22}Si/^{22}O Mirror Gamow-Teller Transitions Reveals the Halo Structure of ^{22}Al

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

Rno_circ_0005139 regulates apoptosis by targeting Wnt5a in rat anorectal malformations

BACKGROUND

The molecular mechanisms underlying anorectal malformations (ARM) are not fully established. Circular RNAs (circRNAs) are new born non-coding RNAs, and their role in ARM is unclear. We assumed that rno_circ_0005139 influences apoptosis and proliferation by acting as a miR-324-3p sponge, and downregulating Wnt5a in ARM.

AIM

To identify the differential expression of circRNAs and mRNAs in a rat ARM model.

METHODS

Sixty-six pregnant Wistar rats were randomly divided into two groups: ARM group (2-imidazolidinethione-induced) and control groups. Embryos were harvested by cesarean delivery, and anorectal tissue was taken on embryonic days 16 (E16), 17 (E17), 19 (E19), and 21 (E21). RNA sequencing and gene microarray analysis was used to identify differentially expressed circRNAs and mRNAs in the ARM in a rat model. We selected 6 circRNAs and 3 mRNAs in the Wnt signal pathway from the result of the RNA sequencing and gene microarray analysis, and quantitative reverse transcription polymerase chain reaction was performed to evaluate their tissue expression. According to bioinformatics prediction, rno_circ_0005139 acted as a miR-324-3p sponge to regulate the expression of Wnt5a. We chose rno_circ_0005139 and Wnt5a as the final candidates. We tested the function of rno_circ_0005139 and the binding sites between rno_circ_0005139 and miR-324-3p, miR-324-3p and Wnt5a by luciferase assays. Co-transfection of rno_circ_0005139 and miR-324-3p was to verify their functional consistency.

RESULTS

We identified 38 upregulated and 42 downregulated circRNAs on E17 (P < 0.05), and 301 mRNAs were upregulated and 256 downregulated in the ARM on E17 (P < 0.05, fold-change > 2.0). We found that rno_circ_0006880 and rno_circ_0011386 were upregulated, whereas rno_circ_0000436, rno_circ_0005139, rno_circ_0009285, rno_circ_0014367, Wnt5a, Wnt10b, and Wnt2b were downregulated in ARM tissues. According to bioinformatics prediction, rno_circ_0005139 acted as a miR-324-3p sponge to regulate the expression of Wnt5a. We chose rno_circ_0005139 and Wnt5a as the final candidates. Because the role and molecular mechanism of rno_circ_0005139 are poorly understood, its effect on apoptosis and proliferation was investigated by in vitro plasmid transfection. A luciferase experiment showed that rno_circ_0005139 could bind with miR-324-3p, which negatively regulated Wnt5a expression. The expression of miR-324-3p was significantly higher in ARM anorectal tissues than that in control group on E17 and E19; Wnt5a expression showed the opposite trend. In addition, a miR-324-3p inhibitor attenuated the effects of rno_circ_0005139 knockdown on ARM development.

CONCLUSION

Rno_circ_0005139 influences cell proliferation and apoptosis by acting as a miR-324-3p sponge, thereby downregulating Wnt5a in ARM. Accordingly, rno_circ_0005139, miR-324-3p, and Wnt5a could be targeted therapeutic factors for ARM.

Construction of an anchoring SSR marker genetic linkage map and detection of a sex-linked region in two dioecious populations of red bayberry

Red bayberry (Morella rubra) is an evergreen fruit tree found in southern China whose whole-genome sequence has recently been published. We updated the linkage map of the species by adding 118 SSR markers and the female-specific marker MrFT2_BD-SEX. The integrated map included eight linkage groups and spanned 491 cM. Eleven sex-associated markers were identified, six of which were located in linkage group 8, in agreement with the previously reported location of the sex-determining region. The MrFT2_BD-SEX marker was genotyped in 203 cultivated accessions. Among the females of the accessions, we found two female-specific alleles, designated W-b (151 bp) and W-d (129 bp). We previously found that 'Dongkui', a female cultivar, could produce viable pollen (we refer to such plants 'Dongkui-male') and serve as the paternal parent in crosses. The genotypes of the MrFT2_BD-SEX marker were W-b/Z in 'Biqi' and W-d/Z in 'Dongkui-male'. The progeny of a cross between these parents produced a 3:1 female (W-) to male (ZZ) ratio and the expected 1:1:1:1 ratio of W-b/W-d: W-b/Z: W-d/Z: Z/Z. In addition, the flowering and fruiting phenotypes of all the F1 progeny fit their genotypes. Our results confirm the existence of ZW sex determination and show that the female phenotype is controlled by a single dominant locus (W) in a small genomic region (59 kb and less than 3.3 cM). Furthermore, we have produced a homozygous "super female" (WW) that should produce all-female offspring in the F2 generation, providing a foundation for commercial use and presenting great potential for use in modern breeding programs.

Genome-wide identification and analysis of the MADS-box gene family and its potential role in fruit development and ripening in red bayberry (Morella rubra)

The MADS-box gene family encodes transcription factors and plays an important role in plant growth and the development of flower and fruit. A perennial dioecious plant, the red bayberry genome has been published recently, providing the opportunity to analyze the MADS-box gene family and its role in fruit development and ripening. Here, we identified 54 MADS-box genes in the red bayberry genome, and classified them into two types based on phylogenetic analysis. Thirteen Type I MADS-box genes were subdivided into three subfamilies and 41 Type II MADS-box genes into 13 subfamilies. A total of 46 MADS-box genes were distributed across eight red bayberry chromosomes, and the other eight genes were located on the unmapped scaffolds. Transcriptome analysis suggested that the expression of most Type II genes was higher than Type I in five female tissues. Moreover, 26 MADS-box genes were expressed during red bayberry fruit development and ten of them showed high expression. qRT-PCR showed that the expression of MrMADS01 (SEP, MIKC^C), with differences between the pale pink and red varieties, increased significantly at the final ripening stage, suggesting it may participate in ripening as positive regulator and related to anthocyanin biosynthesis. These results provide some clues for future study of MADS-box genes in red bayberry, especially in ripening process.

Dietary supplemented antimicrobial peptide microcin J25 improves the growth performance, apparent total tract digestibility, fecal microbiota, and intestinal barrier function of weaned pigs

Microcin J25 (MccJ25) is an antimicrobial peptide produced by a fecal strain of Escherichia coli containing 21 AA. This study was performed primarily to evaluate the effects of MccJ25 as a potential substitute for antibiotics (AB) on growth performance, nutrient digestibility, fecal microbiota, and intestinal barrier function in weaned pigs. In the present study, 180 weaned pigs (7.98 ± 0.29 kg initial BW) were randomly assigned to 1 of 5 treatments, including a basal diet (CON) and CON supplemented with AB (20 mg/kg colistin sulfate; ABD) or 0.5, 1.0, and 2.0 mg/kg MccJ25. On d 0 to 14, dietary supplementation with MccJ25 and ABD had positive effects on ADG, ADFI, diarrhea incidence, and G:F ( < 0.05). Pigs fed the 2.0 mg/kg MccJ25 diet had greater ADG ( < 0.05) and marginally greater G:F ( < 0.10) compared with pigs fed the ABD diet. Compared with the CON diet, the 2.0 mg/kg MccJ25 diet sharply improved ( < 0.05) ADG and G:F and decreased ( < 0.05) diarrhea incidence (d 15 to 28 and d 0 to 28). Apparent digestibility of nutrients in pigs fed 1.0 and 2.0 mg/kg MccJ25 was improved ( < 0.05) compared with that of pigs fed CON and ABD. The serum cytokines IL-6 and IL-1β and tumor necrosis factor-α levels in pigs fed MccJ25 were greater than in pigs fed CON ( < 0.05). Additionally, the IL-10 concentration in pigs fed MccJ25 was sharply increased ( < 0.05) compared with that of pigs fed CON. Pigs fed 1.0 and 2.0 mg/kg MccJ25 diets had remarkably decreased lactate, diamine oxidase, and endotoxin concentrations and fecal numbers ( < 0.05) and improved fecal and numbers ( < 0.05). Compared with the ABD diet, the diet containing 2.0 mg/kg MccJ25 did not increase lactate, diamine oxidase, and endotoxin (d 14) concentrations ( < 0.05) or decrease the and (d 28) numbers ( < 0.05). The diets containing 1.0 and 2.0 mg/kg MccJ25 and ABD (d 28) improved lactate concentration and short-chain fatty acid concentrations, including acetate, propionate, and butyrate, in feces ( < 0.05). Moreover, the pigs fed 2.0 mg/kg MccJ25 had greater lactate, butyrate (d 14), and propionate concentrations than the pigs fed the ABD diet ( < 0.05). In conclusion, dietary supplemented MccJ25 effectively improved performance, attenuated diarrhea and systematic inflammation, enhanced intestinal barrier function, and improved fecal microbiota composition of weaned pigs. Therefore, MccJ25 could be a potential effective alternative to AB for weaned pigs.

Polyketides with different post-modifications from desert endophytic fungus Paraphoma sp

Three new polyketides 4,6,8-trihydroxy-5-methyl-3,4-dihydronaphthalen-1(2H)-one (1), 5,7-dihydroxy-3-(1-hydroxyethyl)-3,4-dimethylisobenzofuran-1(3H)-one (2) and 1-(4-hydroxy-6-methoxy-1,7-dimethyl-3-oxo-1,3-dihydroisobenzofuran-1-yl) ethyl acetate (3) together with seven known analogues (4-10) were isolated from desert endophytic fungus Paraphoma sp. The structures of these compounds were elucidated by analysis of NMR data. The absolute configuration of (1-3) was established on the basis of CD experiments. The possible biosynthetic pathway of compounds (1-10) was suggested, which implied that these secondary metabolites might be originated from polyketide biosynthesis with different post-modification reactions. Compounds 2, and 5-8 were evaluated for bioactivities against plant pathogen A. solani, whereas none of them displayed any biological effects. In addition, compounds 1, 2 and 5-10 were also tested for cytotoxic activities against three human cancer cell lines (HepG2 cells, MCF-7 cells and Hela cells) without biological effects.

Is the Dispersion Relation Applicable for Exotic Nuclear Systems? The Abnormal Threshold Anomaly in the ^{6}He+^{209}Bi System

The threshold anomaly of the phenomenological potential has been known for a long time in nuclear reactions at energies around the Coulomb barrier, where the connection between the real and imaginary potentials is well described by the dispersion relation. However, this connection is not clear yet for some weakly bound nuclear systems, especially for reactions induced by exotic radioactive nuclei. In this study, precise optical potentials of the halo nuclear system ^{6}He+^{209}Bi were extracted via ^{208}Pb(^{7}Li,^{6}He) transfer reactions with energies measured downward to the extremely sub-barrier region. The real potential presents a bell-like shape around the barrier as a normal threshold anomaly in tightly bound nuclear systems. However, the imaginary potential shows an abnormal behavior: it increases first with energy decreasing below the barrier and then falls quickly down to 0. It is the first time the threshold of the imaginary potential has been determined in an exotic nuclear system. Moreover, experimental results show the dispersion relation is not applicable for this system, which may be a common phenomenon for exotic nuclear systems. We discuss possible explanations for such a peculiar behavior, but further study is still desired for the underlying physics.

[Expression of Wnt5a in the terminal rectum of children with anorectal malformation]

OBJECTIVE

To study the expression of Wnt5a protein in the terminal rectum of children with anorectal malformation (ARM) and the possible association between Wnt5a and ARM.

METHODS

Specimens were obtained from 20 children with ARM, 7 children with acquired rectovestibular fistula and 6 children with non-gastrointestinal tract disease (control group). The expression of Wnt5a protein in the terminal rectum was determined by immunohistochemistry and Western blot.

RESULTS

Wnt5a was mainly expressed in the rectum of the myenteric nerve plexus, mucosal layer and submucosa in the control group. Compared with the control group, Wnt5a expression in the terminal rectum decreased significantly in the ARM group, and decreased more significantly in children with high ARM. The results of Western blot showed the expression of Wnt5a protein in the high, intermediate and low ARM groups were significantly lower than that in the acquired rectovestibular fistula and the control groups (P<0.01). The expression of Wnt5a protein in the high and the intermediate ARM groups were also lower than that in the low ARM group (P<0.01). There was no significant difference in the Wnt5a protein expression between the acquired rectovestibular fistula and the control groups.

CONCLUSIONS

The expression of Wnt5a in the termina1 rectum decreases in children with ARM, suggesting Wnt5a may play an important role in the development of ARM.

Ileal duplication with extensive gastric heterotopia in a girl

BACKGROUND

Gastrointestinal duplications are rare congenital abnormalities known to occur at any level of the alimentary tract from the mouth to the anus. The cause of intestinal duplication has not been established. Several theories have been put forward to explain different types of duplications. Some of these duplications are large sized and giant, and only 4 cases have been reported.

METHODS

A 4-year-old girl was referred to our hospital with a history of abdominal pain, abdominal distension, and diarrhea mixed with black blood for 20 days. Technetium-99m scintigraphy identified heterotopic gastric mucosa at the middle and lower abdominal region. Enteric duplication was suspected.

RESULTS

Operatively, duplication was found to be located at the ileum with abnormal hypertrophy in shape, 50 cm of the ileum was resected, and an ileoileal end-to-end anastomosis was made. Stomach-like mucosa and some ring structures were identified instead of the normal intestinal mucosa when opening this ileal duplication. Microscopically, most of mucosa showed gastric corpusfundic glands.

CONCLUSIONS

This is an unusual case of enteric duplication. Ultrasonography, computed tomography and technetium-99m scintigraphy are helpful in the diagnosis of duplication.

Reduction in myocardial infarct size by postconditioning in patients after percutaneous coronary intervention

BACKGROUND

Postconditioning has been shown to reduce infarct size during reperfusion (< 72 hours). However, it is unknown whether the infarct size reduction with postconditioning is a long-term effect after clinical percutaneous coronary intervention (PCI). The present study tested the hypothesis that postconditioning during primary PCI preserves global cardiac function and reduces infarct size in patients after prolonged reperfusion.

METHODS

Fortyone patients undergoing PCI were randomly assigned to a control (n = 18) or postconditioning (n = 23) group within 90 minutes after admission. After predilatation, in the Control group, no intervention was applied in the first 3 minutes of reperfusion, while in the Postconditioning group, three cycles of 30-second angioplasty balloon deflation and 30-second inflation were repetitively applied.

RESULTS

There was a trend toward increased ejection fraction quantified by echocardiography in the Postconditioning group compared to that in the Control group (54 +/- 12.9% vs. 44 +/- 16.7%; p > 0.05). Infarct size represented by the area under the curve of creatine-kinase activity during the first 72 hours of reperfusion was significantly less by 27% in the Postconditioning group than that in the Control group (58,002 +/- 593 vs. 79,787 +/- 681; p = 0.04). After 7 days of reperfusion, infarct size quantified by single-photon emission computed tomography was 27% smaller in the Postconditioning group than that measured in the Control group (31.3 +/- 8.6% vs. 22.8 +/- 6.7% of left ventricle; p < 0.05).

CONCLUSION

This study demonstrates that postconditioning following PCI significantly protects the heart against ischemia/reperfusion-induced injury. More importantly, this study indicates that protection with postconditioning is still apparent 1 week following reperfusion, suggesting long-term protection.

Solid cystic papillary tumor of pancreas in eight children

OBJECTIVE

To estimate the clinical and pathological features of pancreatic solid cystic papillary tumor (SCPT) in children.

METHODS

From 2000 to 2005, 8 cases with SCPT of the pancreas were analyzed retrospectively. All cases but one were females. Average age was 12.8 years. By case review, we discussed the clinical and pathological features of SCPT in children.

RESULTS

The chief complains were abdominal pain and palpable mass. There were 3 cases in the head, 1 case in the body, and 4 cases in the tail of pancreas. The procedures employed included local resection (1 case), distal pancreatectomy (5 cases), pancreaticoduodenectomy (1 case), and biopsy (1 case). Histological examination showed solid with cystic areas and papillary protrusions in the 8 cases; as for immunohistochemical examinations, the positive rate was 100% for alpha-antitrypsin (AACT), 87.5% for vinmentin, and 62.5% for neuron-specific enolase (NSE). The patients were followed up for 2 months to 4 years but one was lost by follow-up and all were alive postoperatively. SCPT in 2 cases relapsed.

CONCLUSION

Occurring predominantly in young females, SCPT is usually curable by surgical resection with a favorable prognosis.

[Solid cystic papillary tumor of pancreas in children---a report of eight cases with literature review]

BACKGROUND & OBJECTIVE

Solid cystic papillary tumor (SCPT) of the pancreas in children is rare with limited references of its clinical features and treatment. Therefore, to estimate the clinicopathologic features of SCPT of the pancreas in children is necessary.

METHODS

Clinical data of 8 children with pathologically confirmed SCPT of the pancreas, treated from 2000 to 2005 with surgery, were analyzed retrospectively. The clinicopathologic features were analyzed with literature review.

RESULTS

All patients were girls but one, with the average age of 12.8 years. The chief complaints were burbulence, abdominal pain, and palpable mass. The tumors were mainly located in the head or tail of the pancreas. Of the 8 patients, 1 received local resection, 5 received distal pancreatectomy, 1 received pancreatico-duodenectomy, and 1 received only biopsy. Seven patients were followed-up for 2 months to 4 years and were still alive; 2 patients suffered recurrence. All cases showed solid with cystic areas and papillary protrusions. Immunohistochemically, the positive rates were 100% for alpha-antitrypsin, 87.5% for vinmentin, and 62.5% for neuron-specific enolase.

CONCLUSIONS

SCPT of the pancreas occurs predominantly in young girls, and its pathogenesis is still unknown. Surgical resection is usually curative, and the prognosis is good.