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Melatonin and serotonin are important signaling and stress mitigating molecules that play important roles across growth and development in plants. Despite many well‐documented responses, a systematic investigation of the entire metabolic pathway (tryptophan, tryptamine, and N‐acetylserotonin) does not exist, leaving many open questions. The objective of this study was to determine the responses of Hypericum perforatum (L.) to melatonin, serotonin, and their metabolic precursors. Two well‐characterized germplasm lines (#4 and 112) created by mutation and a haploid breeding program were compared to wild type to identify specific responses. Germplasm line 4 has lower regenerative and photosynthetic capacity than either wild type or line 112, and there are documented significant differences in the chemistry and physiology of lines 4 and 112. Supplementation of the culture media with tryptophan, tryptamine, N‐acetylserotonin, serotonin, or melatonin partially reversed the regenerative recalcitrance and growth impairment of the germplasm lines. Quantification of phytohormones revealed crosstalk between the indoleamines and related phytohormones including cytokinin, salicylic acid, and abscisic acid. We hypothesize that melatonin and serotonin function in coordination with their metabolites in a cascade of phytochemical responses including multiple pathways and phytohormone networks to direct morphogenesis and protect photosynthesis in H. perforatum.  相似文献   
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It is relatively easy to begin policy documents with a general assertion that ethics will be followed. Less obvious is how to ensure that day‐to‐day activities are consonant with ethical standards. We suggest that using day‐to‐day publication activities as the driver for building policies and procedures can promote ethical practices from the ground up. Although basic principles of ethical publication practice may seem straightforward to some, for others this information may require explanation, interpretation and context. Effective policy development includes big‐picture items as well as more day‐to‐day tactical responsibilities such as those discussed below. Research questions, disciplinary practices, applications and team structures may vary. Thus, no single publication plan or policy solution is right for all teams. It is up to team members to review guidelines for best practices and find the optimal implementation for their situations. Experts in publication management, planning and writing can help large teams manage publication activities. These experts have an obligation to maintain and enhance their skills continually. A strong acumen in publication best practices will allow these publication professionals to better address any possible ethical dilemmas in the future.  相似文献   
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Objective:Comparing the efficacy, safety and outcome of percutaneous intrervention for Budd-Chiari Syndrome (BCS) patients with bilirubin less than 3 and 3–6 mg dl−1.Methods and materials:188 BCS patients having serum bilirubin ≤6 mg dl−1 and underwent percutaneous interventions were divided into two groups based on bilirubin level: 151 patients having bilirubin <3 mg dl−1 were included in Group 1; and 37 patients having bilirubin 3–6 mg dl−1 were included in Group 2. Both group were compare for technical success (successful recanalization of hepatic venous stenosis or creation of portocaval shunt with post-procedure gradient ≤5 mm of Hg), Safety (procedure-related mortality/morbidity or patient required transplantation) and outcome (resolution of clinical symptoms and survival).Results:Technical success was 94.7% in Group 1–89.1% in Group 2 with overall success rate was 93.6%. No significant differences observed between the two groups in regards to procedure related complication. Overall transplant-free survival at 1 and 5 years after intervention in both groups was 96.3 and 91.2% respectively. 1-year and 5-year survivals in Group 1 was 96.7%, and 93.1%, whereas Group 2 was 94.6 and 90.1% with no statically significantly difference between the two groups (p = 0.59). Percutaneous intervention results are good in patients having bilirubin up to 6 mg dl−1, i.e. mild to moderate liver dysfunctions.Conclusion:Technical success, survival and outcome of percutaneous intervention in BCS patients having serum bilirubin 3–6 mg dl−1 was comparable to patients having bilirubin level <3 mg dl−1.Advances in knowledge:Percutaneous intervention treatment is suitable for treatment for symptomatic BCS patients having bilirubin up to 6 mg  dl−1.  相似文献   
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Detection of abnormally elevated levels of molecules in patients with oral cancer may be useful in early diagnosis. These markers can be included in current Histopathology grading and in TNM staging systems of Oral Squamous Cell Carcinoma (OSCC) to make it more efficient. Several pro-angiogenic molecules have been assessed for the same reason. Endothelin-1 (ET-1) is a vasoactive peptide associated with the development and spread of many solid tumors, including Squamous Cell Carcinoma (SCC), but its utility in OSCC has not been confirmed.

Objective

This study aims to evaluate the role of the serum big ET-1 as a biomarker of OSCC, by correlating it with the clinical staging and the histopathological grading.

Material and Methods

Serum levels of big ET-1 measured by the sandwich Enzyme-Linked Immunosorbent Assay (ELISA) in 40 OSCC cases were compared with the levels from the control group using independent t-test. Clinical stages and histopathological grades of OSCC cases were compared in relation to their mean levels of serum big ET-1, one using the Analysis of Variance (ANOVA) test and the other the independent t-test, respectively. The significance of the mean difference between the groups was evaluated by Tukey’s multiple comparison test. All statistical analyses were performed on GraphPad statistical software version 5.0.

Results

By comparing the mean of the big ET-1 concentrations of cases and controls, the independent t-test revealed significant higher big ET-1 concentration of OSCC cases when compared to controls (p<0.0001). Tukey’s multiple comparison test also revealed statistically significant difference among all OSCC stages in relation to the mean levels of serum big ET-1. However, the mean of the big ET-1 concentrations of cases of grade I and of grade II did not differ statistically (p=0.729).

Conclusion

Serum big ET-1 levels may be useful as a diagnostic tool in OSCC and as an adjunct to OSCC staging. However, its use as a prognostic marker warrants larger prospective studies.  相似文献   
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The purpose of this study was to apply photoacoustic imaging (PAI), a relatively new imaging method, to non-invasively map neurovascular dynamics in salivary glands. Dynamic PAI with co-registered ultrasound (US) was performed in mice to monitor salivary gland hemodynamics in response to exogenous muscarinic receptor stimulation (pilocarpine) and blockade (atropine). Pilocarpine increased salivary gland oxygen saturation (%sO2) within minutes after administration, which was abrogated by atropine. A significant correlation was observed between change in %sO2 measured by PAI and saliva secretion. PAI is a novel imaging method that can be used for functional assessment of neurovascular dynamics in salivary glands.  相似文献   
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Temporomandibular joint (TMJ) ankylosis is a debilitating condition usually afflicting children and young adults. Treatment is surgical, i.e., release of the ankylosed joint/s with or without interposition arthroplasty and correction of secondary deformities (mandibular retrusion and asymmetry) This article deals with identifying potential setbacks in TMJ ankylosis surgery and preventing them.KEY WORDS: Ankylosis, complications, temporomandibular joint  相似文献   
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