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Melon (Cucumis melo L.) is a global commercial crop that is sensitive to seed-borne wilt infections caused by Fusarium oxysporum f. sp. melonis (Fom). To address the challenge of detecting Fom contamination, we designed a probe-based real-time PCR method, TDCP2, in combination with rapid or column-based DNA extraction protocols to develop reliable molecular detection methods. Utilizing TDCP2, the detection rate reached 100% for both artificially Fom-inoculated (0.25-25%) and pod-inoculated melon seeds in conjunction with DNA samples from either the rapid or column-based extraction protocol. We performed analyses of precision, recall, and F1 scores, achieving a maximum F1 score of 1 with TDCP2, which highlights the robustness of the method. Additionally, intraday and interday assays were performed, which revealed the high reproducibility and stability of column-based DNA extraction protocols combined with TDCP2. These metrics confirm the reliability of our developed protocols, setting a foundation for future enhancements in seed pathology diagnostics and potentially broadening their applicability across various Fom infection levels. In the future, we hope that these methods will reduce food loss by improving the control and management of melon diseases.

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Ciboria shiraiana is a fungal pathogen and the causal agent of hypertrophy sorosis scleroteniosis (HSS) in mulberry, leading to substantial economic losses in the mulberry fruit-related industry. To obtain HSS resistant resources and investigate the resistance mechanism, the resistances of 14 mulberry varieties were assessed. Morus laevigata Wall. (MLW) varieties showed strong resistance to C. shiraiana, and the pathogen's infection was associated with mulberry fluorescence. Stigmas were identified as the infection site through cutting experiments. Susceptible varieties (S-varieties) displayed secretory droplets on their stigma papillar cell surfaces, while MLWs lacked these secretions. Correlation analysis between the secretion rate and the diseased fruit rate indicated that the differences between resistant varieties (R-varieties) and S-varieties were related to the stigma type. Furthermore, comparative transcriptome analysis was performed on stigma and ovary samples from R- and S-varieties. Compared with the stigma of R-varieties, the key differentially expressed genes (DEGs) with significantly higher expression in S-variety stigmas mainly participated in the fatty acid biosynthetic process. In R-variety stigmas and ovaries, the transcript levels of DEGs involved in defense response, including resistance (R) genes, were significantly higher than that of S-varieties. Overexpression of MlwRPM1-2 and MlwRGA3 enhances resistance to C. shiraiana and Sclerotinia sclerotiorum, but not Botrytis cinerea in tobacco. These findings help us explain the different resistance mechanisms of mulberry to C. shiraiana, and the critical defense genes in R-varieties can be applied to breeding antifungal plant varieties.

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The heading date and grain size are two essential traits affecting rice yield. Here, we found that OsMOS1 promotes rice heading and affects its grain size. Knocking out OsMOS1 delayed heading, while the overexpression of OsMOS1 promoted heading in rice under long-day conditions. The transcriptions of the heading activators Ehd1, Hd3a, and RFT1 were decreased and the heading repressor Hd1 was increased in the osmos1 mutant. Conversely, the overexpression of OsMOS1 promoted the expressions of Ehd1, Hd3a, and RFT1, but inhibited the expression of Hd1. This suggests that OsMOS1 may control heading in rice by modulating the transcriptions of Ehd1, Hd3a, RFT1, and Hd1. In addition, knocking out OsMOS1 led to larger grains with longer grain lengths and higher grain weights. The seed cell size measurement showed that the cell lengths and cell widths of the outer glume epidermal cells of the osmos1 mutant were greater than those of the wild type. Furthermore, we also found that the overexpression of OsMOS1 in the Arabidopsis mos1 mutant background could suppress its phenotypes of late flowering and increased seed size. Thus, our study shows a conserved function of MOS1 in rice and Arabidopsis, and these findings shed light on the heading and seed size regulation in rice and suggest that OsMOS1 is a promising target for rice yield improvement.

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Chromatin remodeling proteins modulate nucleosome dynamic to affect global gene expression and other cellular processes. Their roles in the regulation of plant growth and development have been widely reported, but their roles in plant stress resistance, especially disease resistance, have not been extensively investigated. Here, we show that the Arabidopsis Immunity Switch (ISWI) chromatin-remodeling factors CHR11 and CHR17, are negative regulators of plant disease resistance. The loss of both CHR11 and CHR17 function led to upregulation of a large set of defense response genes in the absence of pathogen infection. The chr11 single mutant showed enhanced resistance against a virulent pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). Further analysis revealed that mutation of Phytoalexin Deficient4 (PAD4) reduced the upregulation of defense gene expression as well as resistance against Pst DC3000 in the chr11 chr17 double mutant. However, mutation of PAD4 does not rescue the growth defects of chr11 chr17. Together, our study revealed a function of ISWI in repressing defense response under non-pathogenic conditions and indicates distinct target genes of ISWI in regulating plant growth and plant immunity.

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Melanoma is a highly lethal cutaneous cancer with the tendency for early invasion and metastasis. Integrated miRNA transcriptome sequence analysis of human melanoma tumors and adjacent control tissues identified 17 miRNAs differentially expressed in melanoma tissues: let-7a-5p, let-7b-5p, let-7c, miR-374a-3p, miR-100-5p, miR-7, miR-195, miR-1908, miR-214, miR-221, miR-199a-5p, miR-21, miR-18, miR-34a, miR-199a-3p, miR-92a and miR-106b. Among these, miR-34a was most significantly down-regulated in melanoma tissues, and its expression correlated with TNM melanoma stage. miR-34a overexpression inhibited expression and activity of the transcription factor ZEB1, resulting in decreased proliferation and migration of melanoma cells. Moreover, miR-34a overexpression inhibited ZEB1 expression and melanoma tumor growth in vivo, in a melanoma nude mouse model. Together, these findings demonstrate that miR-34a inhibits melanoma growth by targeting the proto-oncogene ZEB1 and suggest the miR-34a -ZEB1 axis may serve as a novel target for melanoma treatment.

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Heterotrimeric guanine-nucleotide-binding proteins (G-proteins) play key roles in responses to various abiotic stress responses and tolerance in plants. However, the detailed mechanisms behind these roles remain unclear. Mulberry (Morus alba L.) can adapt to adverse abiotic stress conditions; however, little is known regarding the associated molecular mechanisms. In this study, mulberry G-protein genes, MaGα, MaGß, MaGγ1, and MaGγ2, were independently transformed into tobacco, and the transgenic plants were used for resistance identification experiments. The ectopic expression of MaGα in tobacco decreased the tolerance to drought and salt stresses, while the overexpression of MaGß, MaGγ1, and MaGγ2 increased the tolerance. Further analysis showed that mulberry G-proteins may regulate drought and salt tolerances by modulating reactive oxygen species' detoxification. This study revealed the roles of each mulberry G-protein subunit in abiotic stress tolerance and advances our knowledge of the molecular mechanisms underlying G-proteins' regulation of plant abiotic stress tolerance.

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Heterotrimeric guanine-nucleotide-binding proteins (G-proteins) consist of α, ß and γ subunits and play important roles in response and tolerance to abiotic stresses in plants, but the function of the heterotrimeric G-protein ß subunit in response to drought remains unclear. In the present study, the AGB1 mutants (agb1-2-1 and agb1-3-2) were more sensitive to drought than the wild-type. The overexpression of mulberry (Morus alba L.) G-protein ß subunit in transgenic tobacco (Nicotiana tabacum L.) significantly enhanced the plants' drought tolerance. The transgenic tobacco plants had higher proline contents and peroxidase activities, and lower malonaldehyde and hydrogen peroxide contents and superoxide free radical accumulations under drought conditions. Additionally, transcript levels of the tobacco antioxidative genes, NtSOD and NtCAT, increased in drought-stressed transgenic tobacco plants. Thus, the heterotrimeric G-protein ß subunits positively regulate drought tolerance in plants.

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Antigenicity is the biggest obstacle of xenogeneic acellular dermal matrices (ADM) as dermal scaffold in treatment of large-area skin defect. We prepared ADM by repeated freezing and thawing and ultrasonic process, and then injected the ADM homogenate and degradation product into porcine skin to evaluate the effectiveness of the decellularized method and the antigenicity of porcine ADM. In this work, chinese miniature pigs (n = 10) were sensitized by subcutaneous injection with human ADM degradation products on days 0, 7, and 14. After 21 days, their abdominal skin was divided into five regions for intradermal injection of porcine ADM homogenate (PADM), PADM degradation products, human ADM homogenate (HADM), HADM degradation products, and physiological saline (negative control). Positive controls (n = 2) were processed with fresh human skin homogenate by the same method. The skin manifestations in related areas were observed at 24 and 48 h and then the skin was subjected to histopathological and immunohistochemical analysis. The results showed that skin erythema and hydroderma were not observed in all groups but in positive control group. The histopathological and immunohistochemical results confirmed that no inflammatory cell infiltration, irregular extracellular matrix, IL-2, and IFN-γ expression were observed in all four test groups. Our results suggest that the combination with repeated freeze-thawing and ultrasonication can be an effective method to prepare ADM, which has great potential in clinical application.

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AIM: To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori (H. pylori) treatment in children with H. pylori-associated functional dyspepsia. METHODS: Children with H. pylori-associated functional dyspepsia were enrolled in this study. H. pylori infection was confirmed by positive bacterial culture results. All of the children received triple H. pylori eradication therapy (a 2 wk course of omeprazole, amoxicillin, and clarithromycin). The children were divided into two groups based on the success of the H. pylori treatment: group 1 (eradicated) - patients who had a negative 13C-urea breath test 2 mo after the end of therapy; and group 2 (non-eradicated) - patients who had a positive 13C-urea breath test. Plasma ghrelin, gastric ghrelin mRNA, and the body mass index were evaluated in both groups before and after the H. pylori treatment. The plasma ghrelin levels were measured by a radioimmunoassay. The expression of gastric ghrelin mRNA was determined by real-time reverse transcription polymerase chain reaction. RESULTS: A total of 50 children with H. pylori-associated functional dyspepsia were treated with triple H. pylori eradication therapy. The mean age of the children was 5.52 ± 0.83 years, and there were 28 males and 22 females. Among the 50 H. pylori-positive children, 30 successfully achieved eradication, and 20 did not. The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment, respectively, which was a significant increase (P = 0.001). However, the mean plasma ghrelin level of group 2 before and after the H. pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10 ng/L (P = 0.785). The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2. Similarly, the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08. After treatment, the level was 3.11 ± 0.65, which was significantly different (P = 0.023). The gastric ghrelin mRNA expression in group 2 did not change significantly during the treatment (2.82 ± 0.44 vs 2.79 ± 0.31, P = 0.875). The plasma ghrelin and gastric ghrelin mRNA levels in group 1 increased substantially after the treatment but did not do so in group 2. In addition, the body mass index the two groups did not differ significantly 2 mo before and after the H. pylori treatment. CONCLUSION: H. pylori eradication increases the plasma and tissue ghrelin levels in children with H. pylori-associated functional dyspepsia.

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Glucagon induces intracellular Ca(2+) ([Ca(2+)](i)) elevation by stimulating glucagon receptor (GCGR). Such [Ca(2+)](i) signaling plays important physiological roles, including glycogenolysis and glycolysis in liver cells and the survival of beta-cells. Previous studies indicated that phospholipase C (PLC) might be involved in glucagon-mediated [Ca(2+)](i) response. Other studies also debated whether cAMP accumulation mediated by GCGR/G alpha(s) coupling contributes to [Ca(2+)](i) elevation. But the exact mechanisms remain uncertain. In the present study, we found that glucagon induces [Ca(2+)](i) elevation in HEK293 cells expressing GCGR. Removing extracellular Ca(2+) did not affect glucagon-stimulated [Ca(2+)](i) response. But depleting the intracellular Ca(2+) store by thapsigargin completely inhibited glucagon-induced [Ca(2+)](i) response. Experiments with forskolin and adenylyl cyclase inhibitor revealed that cAMP is not the cause of [Ca(2+)](i) response. Further studies with G alpha(q/11) RNAi and pertussis toxin (PTX) indicated that both G alpha(q/11) and G alpha(i/o) are involved. Combination of G alpha(q/11) RNAi and G alpha(i/o) inhibition almost completely abolished glucagon-induced [Ca(2+)](i) signaling.

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OBJECTIVE: This study aimed to investigate the value of the liver function test in the differential diagnosis of infantile hepatitis syndrome (IHS) and biliary atresia (BA) by analyzing seven conventional serological markers in this test using receiver operating characteristic (ROC) curves. METHODS: Serum levels of seven conventional serological markers: alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (gamma-GT), alkaline phosphatase (ALP), total bilirubin (TB), conjugated bilirubin (CB) and serum albumin (ALB) were measured in 103 children with IHS and 60 children with BA. ROC curves were used to evaluate the sensitivity, specificity, positive and predictive values and optimal cut-off. The united tests (parallel test and serial test) of gamma-GT, TB and CB were performed to elevate diagnostic efficiency. RESULTS: Compared with the IHS group, the BA group had significantly increased serum ALT, AST, gamma-GT, TB and CB levels (p<0.01). The area under ROC (AUCROC) of AST, gamma-GT, CB and TB was 0.77, 0.881, 0.841 and 0.87, respectively. gamma-GT showed the highest AUCROC, specificity, positive predictive value and positive likelihood ratio in the diagnosis of BA, followed by CB, TB and AST in turn. The negative predictive value of CB was the highest, followed by TB. The negative likelihood ratio of CB was the lowest but its Youden index was the highest. The Youden index of gamma-GT and TB was lower than that of CB. After the parallel tests, the sensitivity and negative predictive value of gamma-GT, CB and TB increased to 100%. After the serial tests, the specificity of gamma-GT, CB and TB increased to 90.4% and the positive predictive value increased to 87.5%. CONCLUSIONS: The measurement of gamma-GT, TB and CB levels are valuable in the differential diagnosis of BA and IHS. An imaging examination is required in the parallel test positive patients.

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OBJECTIVE: To study the relationship of the types of Helicobacter pylori (H. pylori) strains with the classification and the severity of chronic gastro-duodenal diseases in children. METHODS: One hundred and fifteen children with chronic upper gastrointestinal symptoms who were diagnosed as H. pylori infection by gastroscopy were enrolled in this study. H. pylori strains were serotyped by immunoblot technique. The gastric biopsy specimens of all patients were studied histologically. RESULTS: Type I H. pylori strains were confirmed in 84 cases (73.0%), intermediate type strains in 21 cases (18.3%), and type II strains in 10 cases (8.7%). Type I H. pylori strains infection caused a moderate gastric mucosal inflammation in 83 cases and a severe inflammation in 1 case. Intermediate type H. pylori strains infection caused a moderate gastric mucosal inflammation in 21 cases. Type II H. pylori strains infection caused a mild gastric mucosal inflammation in 2 cases and a moderate inflammation in 8 cases. Different types of H. pylori strains resulted in different severity of gastric mucosal inflammation (x2=15.444, P < 0.01). The gastric mucosal inflammation due to type I H. pylori strains was the most severe, while the inflammation due to type II H. pylori strains was relatively mild. The incidence of nodulus lymphaticus of gastric mucosa due to type I, type II and intermediate type H. pylori strains infection was 76.2%, 47.6% and 40.0%, respectively (x2=10.171, P < 0.01). The classification of chronic gastro-duodenal diseases was not associated with the types of H. pylori strains. CONCLUSIONS: Type I strains were the leading cause of H. pylori infection in children. All of types of H. pylori strains can cause pathohistologic changes of gastric mucosa. Type I H. pylori strains infection can result in the most severe gastric mucosal inflammation and the highest incidence of nodulus lymphaticus. The immunoblot serotyping of H.pylori strains may be useless for the classification of chronic upper gastrointestinal diseases but it is helpful for the evaluation of the severity of the diseases in children.

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The occurrence of eating disorders in Chinese adolescents is increasing. However the cause, diagnosis, treatment and prognosis of this disorder are rarely reported by pediatricians. This paper investigated the cause and treatment of six cases of eating disorders in adolescent patients. The medical data of six cases of eating disorders in the Shanghai Children's Medical Center from January 2003 to September 2005 were retrospectively reviewed. The patients were 5 girls and 1 boy, whose onset ages ranged from 12.4 to 15.8 years. They were initially referred to the clinic between 12.9 to 16.7 years, with a course of disease varying from three to twelve months. The patients' body mass index (BMI) varied from 9.07 to 17.0. Four out of the six patients were hospitalized because of low temperature, low blood pressure, bradycardia, dehydration and multiple systems damages. The other two were treated in the out-patient clinic. Based on the medical history and physical examination as well as laboratory findings, five of them were diagnosed with anorexia nervosa and the other one were bulimia nervosa. All of the patients were under the care of a team consisting of pediatricians, dietitians, psychiatrists and nurses. When the patients whose vital signs were unstable, medical treatment focused on life sustention and they were kept on beds compulsively and given nutrition transfusion. Meanwhile cognition and behavior therapy was administered to help the patients find out the internal and environmental factors related to the development of this disorder, establish a new conception of healthy weight, and correct their abnormal eating behaviors. The patients who had a severe distortion of body image and a big resistance to the treatment were additionally administered with psychiatry drugs. After treatment, three patients set up a healthy eating behavior, their body weights gradually recovered and they had no relapse during a 1-year follow-up. The other three patients retained some abnormal eating behaviors and their body weights were always below normal. It was found that eating disorders in adolescents may be triggered by some environmental factors, such as comments on body shape from their peers, fashion influence, academic pressures, and problems in communication. Since the patients' abnormal eating behaviors were masked or neglected by parents at the early stage of the disease and the clinical presentations were related to multiple systems, it is difficult to make an early diagnosis and treatment. It is important to improve the pediatricians' knowledge of eating disorders of adolescents and perform cooperation between a multidisciplinary team for the early diagnosis and treatment of this disorder.

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