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1.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(1): 94-98, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32148239

RESUMO

OBJECTIVE: To evaluate the value of lung ultrasound score (LUS) on predicting weaning outcome in patients with intro-abdominal infection (IAI) undergoing mechanical ventilation. METHODS: Patients with IAI undergoing mechanical ventilation admitted to Research Institute of General Surgery of East War Zone Hospital and intensive care unit (ICU) of the First People's Hospital of Lianyungang from January to December in 2018 were included. The patients who satisfied weaning criteria were enrolled in the weaning process, which included spontaneous breathing trial (SBT) and extubation. They were divided into SBT success group and SBT failure group according to whether passed 120-minute SBT or not. LUS scores before and after SBT were compared between the two groups. The patients in the SBT success group were extubated, and they were divided into successful extubation group and failed extubation group for sub-group analysis according to whether re-intubation was needed in 48 hours after extubation. LUS score before extubation (at the end of SBT) and 48 hours after extubation (48 hours after extubation in the successful extubation group or before re-intubation in the failed extubation group) were compared. The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of LUS score before SBT for SBT failure and LUS score before extubation for the failure. RESULTS: A total of 76 patients with IAI undergoing mechanical ventilation were included. Twenty-three patients had duration of mechanical ventilation less than 48 hours, severe chronic obstructive pulmonary disease (COPD), tracheotomy or automatic discharge were excluded, and 53 patients were enrolled. SBT was failed in 9 patients, and successfully performed in 44 patients, of whom 23 patients with successful extubation, and 21 with failed extubation. The LUS scores before and after SBT in the SBT failure group were significantly higher than those in the SBT success group (before SBT: 13.22±1.99 vs. 10.79±1.64, t = -3.911, P = 0.000; after SBT: 19.00±1.12 vs. 13.41±1.86, t = -8.665, P = 0.000). ROC curve analysis showed that the area under ROC curve (AUC) of LUS score before SBT for predicting SBT failure was 0.82 [95% confidence interval (95%CI) was 0.67-0.98, P = 0.002]. When the optimum cut-off value was 12.5, the sensitivity was 66.7%, and the specificity was 84.1%. Sub-group analysis showed that the LUS scores before and after extubation in the failed extubation group were significantly higher than those in the successful extubation group (before extubation: 14.19±1.60 vs. 12.69±1.81, t = -2.881, P = 0.006; after extubation: 16.42±1.59 vs. 12.78±1.54, t = -7.710, P = 0.000). ROC curve analysis showed that the AUC of LUS score before extubation for predicting the failure was 0.81 (95%CI was 0.69-0.92, P = 0.000). When the optimum cut-off value was 13.5, the sensitivity was 80.0%, and the specificity was 65.2%. CONCLUSIONS: LUS score can effectively predict SBT outcome, risk of re-intubation after extubation in patients with IAI undergoing mechanical ventilation.

3.
Opt Express ; 28(1): 345-359, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118963

RESUMO

Orbital angular momentum (OAM) modes of electromagnetic (EM) waves have been extensively studied to obtain more than two independent channels at a single frequency. Thus far, however, multiple radiators have been used to achieve this goal in wireless communications. For the first time, a single radiator was designed to simultaneously transmit three OAM waves in free space at the same frequency. Our design makes use of the radiating resonant modes of a dielectric resonator antenna (DRA). For demonstration, a wireless communication system consisting of a pair of transmitting and receiving OAM DRAs was setup and measured. Three EM waves carrying three different signals were transmitted and received successfully, increasing the system throughput without requiring any complex signal processing algorithms. It confirms that a single radiator can wirelessly transmit more than two independent EM waves at a single frequency by using multi-OAM modes. The work is useful for the future high-speed wireless communication systems.

4.
Sensors (Basel) ; 20(3)2020 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-32024314

RESUMO

Quantitative online detection of microcracks in long-distance oil and gas pipelines is an international problem, and the effective detection method is still lacking. In this paper, a mathematical model of non-uniform distribution of crack magnetic charges is established based on the stress distribution laws of pipeline cracks under internal pressure. The weak magnetic signal characteristics of pipeline cracks with different sizes are analyzed. The internal pressure increasing factor of weak magnetic signals are extracted to analyze the corresponding relationship between crack size and weak magnetic signals. The experimental study of the X70 pipeline is carried out. The results show that the axial component of the weak magnetic signal at the crack has a maximum value near the tip, and a minimum value appears in the middle of the crack. The internal pressure increasing factor is introduced to quantify the weak magnetic signal, the crack is in a safe state (not expanding) when the internal pressure increasing factor is positive, the weak magnetic signal has a linear relationship with the crack size. However, the crack is in a dangerous state when the internal pressure increasing factor is negative, and the pipeline crack will expand as the internal pressure increases.

5.
Otolaryngol Head Neck Surg ; : 194599820907893, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32097087

RESUMO

We retrospectively analyzed 17 patients with esophageal stent who underwent cervical esophageal and/or hypopharyngeal stenosis after total laryngectomy (TL) from January 2014 to January 2018. The success rate of stent implantation was 100%. Dysphagia in 16 patients improved to class 0 or 1 (16/17, 94.12%) after stent implantation and in 1 patient was improved to class 2 (1/17, 5.88%). Two patients died of tumor progression at 7 months and 11 months after stent implantation, respectively, but both could eat semi-solid/solid food before death. Dysphagia was resolved in the remaining 15 patients, and there was no recurrence of dysphagia including feeding obstruction during follow-up. Therefore, this case series concludes that the esophageal stent position after TL can be much higher than that of patients with normal pharyngeal structures. Esophageal stent implantation is a feasible and effective treatment for patients with laryngopharyngeal/esophageal stenosis following TL.

6.
Biosci Rep ; 40(3)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32073611

RESUMO

Hyperglycemia-induced renal tubular cell injury is thought to play a critical role in the pathogenesis of diabetic nephropathy (DN). However, the role of miRNAs in renal tubular cell injury remains to be fully elucidated. The aim of the present study was to investigate the role and mechanisms of miRNAs protecting against high glucose (HG)-induced apoptosis and inflammation in renal tubular cells. First, we analyzed microRNA (miRNA) expression profiles in kidney tissues from DN patients using miRNA microarray. It was observed that miRNA-140-5p (miR-140-5p) was significantly down-regulated in kidney tissues from patients with DN. An inverse correlation between miR-140-5p expression levels with serum proteinuria was observed in DN patients, suggesting miR-140-5p may be involved in the progression of DN. HG-induced injury in HK-2 cells was used to explore the potential role of miR-140-5p in DN. We found that miR-140-5p overexpression improved HG-induced cell injury, as evidenced by the enhancement of cell viability, and inhibition of the activity of caspase-3 and reactive oxygen species (ROS) generation. It was also observed that up-regulation of miR-140-5p suppressed HG induced the expressions of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß and IL-6 in HK-2 cells. In addition, TLR4, one of the upstream molecules of NF-κB signaling pathway, was found to be a direct target of miR-140-5p in the HK-2. Moreover, the HG-induced activation of NF-κB signaling pathway was inhibited by miR-140-5p overexpression. These results indicated that miR-140-5p protected HK-2 cells against HG-induced injury through blocking the TLR4/NF-κB pathway, and miR-140-5p may be considered as a potential prognostic biomarker and therapeutic target in the treatment of DN.

7.
Can J Gastroenterol Hepatol ; 2020: 5143013, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104670

RESUMO

Background and Aim. Upper gastrointestinal bleeding is a threat to patients with gastric varices (GVs). Previous studies have concluded that both transjugular intrahepatic portosystemic shunt (TIPS) and balloon-occluded retrograde transvenous obliteration (BRTO) are effective treatments for patients with GV. We aimed to compare the efficiency and outcomes of these two procedures in GV patients through meta-analysis. Methods: The PubMed, Cochrane Library, EMBASE, and Web of Science databases were searched using the keywords: GV, bleeding, TIPS, and BRTO to identify relevant randomized controlled trials and cohort studies. The overall survival (OS) rate, imminent haemostasis rate, rebleeding rate, technical success rate, procedure complication rate (hepatic encephalopathy and aggravated ascites), and Child-Pugh score were evaluated. Randomized clinical trials and cohort studies comparing TIPS and BRTO for GV due to portal hypertension were included in our meta-analysis. Two independent reviewers performed data extraction and assessed the study quality. A meta-analysis was performed to calculate risk ratios (RRs), mean differences (MDs), and 95% CIs using random effects models. Results: A total of nine studies fulfilled the inclusion criteria. There was a significant difference between TIPS and BRTO in the OS rate (RR, 0.81 (95% CI, 0.66 to 0.98); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90); P=0.03) and rebleeding rate (RR, 2.61 (95% CI, 1.75 to 3.90). Conclusions: In this meta-analysis, BRTO brought more benefits to patients, with a higher OS rate and lower rebleeding rate. BRTO is a feasible method for GVB.

8.
Biochim Biophys Acta Mol Basis Dis ; 1866(5): 165685, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953217

RESUMO

Progression of acute pancreatitis (AP) into a severe form usually results in a life-threatening condition with multiple organ dysfunction, and in particular acute lung injury (ALI), often contributes to the majority of AP-associated deaths. Increasing evidence has shown that uncontrolled activation of the immune system with rapid production of inflammatory cytokines play a dominant role in this process. As an intracellular inflammatory signaling platform, the NOD-like receptor protein 3 (NLRP3) inflammasome, is recently reported to be involved in the pathogenesis of AP progression, however, the relationship between NLRP3 inflammasome activation and AP-associated lung injury remains unclear yet. Here, we show that NLRP3 inflammasome activation and subsequent pyroptosis in alveolar macrophages (AMs) is responsible for the lung injury secondary to AP. In addition, plasma-derived exosomes from AP mice is capable of triggering NLRP3-dependent pyroptosis in AMs. Inhibition of exosome release or uptake in vivo by inhibitors substantially suppresses AMs pyroptosis and thereby alleviates AP-induced pulmonary lesion. Collectively, the current work reveals for the first time the involvement of NLRP3-dependent pyroptosis induced by plasma exosomes in the pathogenesis of AP-induced ALI, suggesting that the exosome-mediated NLRP3 inflammatory pathway is a potential therapeutic target for the treatment of lung injury during AP.

9.
Eur J Pharm Sci ; 144: 105214, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31935464

RESUMO

There are many kinds of potentially undesirable teeth. At present, surgical extraction is the most efficient way to eliminate these teeth, but it's very complex and invasive. In this study, we investigated the effects of bleomycin (BLM) on dental follicle and tooth eruption as a potential conservative therapy for undesirable teeth. Our data showed that local injection of 0.2 U/kg BLM had no significant effects on tooth eruption compared to the control group in Wistar rats. With higher dose of BLM (0.5 or 2 U/kg), the eruption of treated teeth was interrupted and their root formation failed until 4 weeks postnatal without significant systemic toxicity. Additionally, those effects were not depending on the toxicity of overdose evidenced by TUNEL assay. In summary, injecting BLM into dental follicle at an early stage could interrupt tooth development and eruption, and may prevent the potentially clinical problems resulting from undesirable teeth instead of surgical removal.

10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 74-80, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31950793

RESUMO

Objective: To develop an assay for determination of 8-oxo-2'-deoxyguanosine and cotinine in human urine by hydrophilic chromatography tandem mass spectrometry (HILIC-MS/MS) with isotope dilution. Methods: The urine supernatant was 1∶5 diluted with 3 mmol/L ammonium formate aqueous solution containing 15N 5-8-OHdG and D 3-cotinine as internal standard. After being filtered through a 0.22 µm water filter, the sample solution was injected into ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Separation was performed on ACQUITY UPLC® BEH HILIC column (50 mm×3.0 mm, 1.7 µm) with isocratic elution (A∶B=10∶90) at 40 ℃. The mobile phase was composed with acetonitrile (B) and 3 mmol/L ammonium formate water soulution (A). The flow rate was 0.3 mL/min. Positive ion scan-multiple reaction monitoring (MRM) mode were used for monitoring and internal standard curves were applied for quantification. Results: Good linearity was obtained under the optimal conditions. Detection limits for 8-OHdG and cotinine were 0.064 µg/L and 0.035 µg/L respectively, the quantitation limits were 0.21 µg/L and 0.12 µg/L respectively, and the recoveries of the spiked urine samples were 92.6%-102% and 102%-106% respectively. Statistical analysis of 40 urine sample determination results obtained by using the above assay showed that there were significant differences in tobacco smoke exposure and tobacco-specific nitrosamine intake between active and passive smoker ( P<0.05). The concentration of NNAL and cotinine were higher in urine samples of active smoker. Tobacco smoke exposure was positively correlated with tobacco specific nitrosamine intake in both active and passive smokers (the correlation coefficients were 0.487 and 0.786 respectively, P<0.05). Conclusion: We successfully established a simple and fast assay for simultaneously detecting 8-oxo-2'-deoxyguanosine and cotinine in human urine. It was sensitive and accurate for quntification via the calibration by the isotope internal standards, and can meet the needs of batch analysis.


Assuntos
Cromatografia Líquida de Alta Pressão , Cotinina , Espectrometria de Massas em Tandem , Urinálise , /urina , Cotinina/urina , Humanos , Isótopos/química , Urinálise/métodos
11.
Lancet Gastroenterol Hepatol ; 5(3): 267-275, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31926918

RESUMO

BACKGROUND: Chemoprevention of colorectal adenoma and colorectal cancer remains an important public health goal. The present study aimed to investigate the clinical potential and safety of berberine for prevention of colorectal adenoma recurrence. METHODS: This double-blind, randomised, placebo-controlled trial was done in seven hospital centres across six provinces in China. Individuals aged 18-75 years who had at least one but no more than six histologically confirmed colorectal adenomas that had undergone complete polypectomy within the 6 months before recruitment were recruited and randomly assigned (1:1) to receive berberine (0·3 g twice daily) or placebo tablets via block randomisation (block size of six). Participants were to undergo a first follow-up colonoscopy 1 year after enrolment, and if no colorectal adenomas were detected, a second follow-up colonoscopy at 2 years was planned. The study continued until the last enrolled participant reached the 2-year follow-up point. All participants, investigators, endoscopists, and pathologists were blinded to treatment assignment. The primary efficacy endpoint was the recurrence of adenomas at any follow-up colonoscopy. Analysis was based on modified intention-to-treat, with the full analysis set including all randomised participants who received at least one dose of study medication and who had available efficacy data. The study is registered with ClinicalTrials.gov, number NCT02226185; the trial has ended and this report represents the final analysis. FINDINGS: Between Nov 14, 2014, and Dec 30, 2016, 553 participants were randomly assigned to the berberine group and 555 to the placebo group. The full analysis set consisted of 429 participants in the berberine group and 462 in the placebo group. 155 (36%) participants in the berberine group and 216 (47%) in the placebo group were found to have recurrent adenoma during follow-up (unadjusted relative risk ratio for recurrence 0·77, 95% CI 0·66-0·91; p=0·001). No colorectal cancers were detected during follow-up. The most common adverse event was constipation (six [1%] of 446 patients in the berberine group vs one [<0·5%] of 478 in the placebo group). No serious adverse events were reported. INTERPRETATION: Berberine 0·3 g twice daily was safe and effective in reducing the risk of recurrence of colorectal adenoma and could be an option for chemoprevention after polypectomy. FUNDING: National Natural Science Foundation of China.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31923124

RESUMO

STUDY DESIGN: A prospective cohort study. OBJECTIVE: We conducted a prospective cohort study to identify the association between steroids and clinical worsening and compare outcomes between patients with and without preoperative steroid administration. SUMMARY OF BACKGROUND DATA: Patients with SDAVFs often were misdiagnosed and treated with steroids which led to acute worsening. METHODS: Patients with angiographically-confirmed SDAVFs were recruited consecutively between March 2013 and December 2014 in two referral centers. We reviewed the history of all the patients to identify those patients who were treated with steroids prior to exclusion of the fistulas. Modified Aminoff & Logue's scale (mALS) was used to evaluate the spinal cord function at different time points: before and after steroid administration, before operation and at 1-year follow-up. Paired t tests were used to assess the mALS of patients with steroid administration at different time points. Unpaired t tests and Pearson chi-square test were used to assess differences between patients with and without steroid administration. RESULTS: 18 patients with (18.2%) and 81 patients without (81.8%) steroid administration were included in this study. At baseline, there were no difference between both patient groups, in regards to age, gender, duration, location of fistula, treatment and preoperative mALS. However, patients without steroid administration had statistically significant better outcome according to their mALS at 1-year follow-up (P < 0.05). CONCLUSION: Steroid administration can induce acute clinical worsening in patients with SDAVFs that may persist despite successful obliteration of the fistula and should thus be avoided. LEVEL OF EVIDENCE: 3.

13.
Per Med ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31984849

RESUMO

Aim: This study aimed to explore leukocyte telomere length (LTL) in the prediction of the severity of coronary artery disease (CAD). Materials & methods: A total of 359 CAD patients who underwent coronary angiography were enrolled in this study. Severity of coronary artery was assessed by Gensini score (GS). Results: LTL is negatively correlated with GS (Spearman's rank correlation coefficient = -0.335; p < 0.001). Multivariate logistic regression results showed that LTL was an independent predictor of high GS (p = 0.001). Area under the curve value of LTL for predicting high GS was 0.659 (p < 0.001). Conclusion: LTL could be considered as a potential predictor of the severity of coronary artery in patients with CAD.

14.
World Neurosurg ; 133: e320-e326, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520758

RESUMO

BACKGROUND: Compared with intracranial aneurysms (IAs) at other locations, pericallosal artery aneurysms (PAAs) have demonstrated an extremely high risk of rupture. However, owing to their rarity, our understanding of their morphological characteristics has been limited, and whether the morphological characteristics of PAAs contribute to this high rupture risk has remained unexplored. In the present study, we aimed to provide a detailed description of the morphological characteristics of PAAs and investigate the association between its morphology and rupture risk compared with anterior circulation IAs at other locations. METHODS: A total of 40 patients with 45 PAAs and 348 patients with 392 anterior circulation IAs at other locations were recruited. The clinical and radiological data for these patients were retrospectively reviewed. The differences in the morphological parameters, including the aneurysm diameter, neck width, height, width, parent artery diameter, inflow angle, aspect ratio (AR), size ratio (SR), and aneurysm diameter/width ratio, between PAAs and other IA groups were compared. RESULTS: Of the 45 PAAs, 22 (48.9%) had ruptured. The proportion of ruptured aneurysms was greater for PAAs than for anterior circulation IAs at other locations. For both ruptured and unruptured anterior circulation IAs, PAAs had the highest AR and SR among all IA groups and had the largest inflow angle. CONCLUSION: The morphological characteristics of PAAs are unique. Compared with other anterior circulation IAs, PAAs have significantly increased ARs, SRs, and inflow angles, which, ultimately, promote their high propensity toward rupture.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Artéria Cerebral Anterior/diagnóstico por imagem , Angiografia Cerebral/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Adolescente , Adulto , Idoso , Aneurisma Roto/epidemiologia , Aneurisma Roto/patologia , Artéria Cerebral Anterior/patologia , Corpo Caloso/irrigação sanguínea , Suscetibilidade a Doenças , Feminino , Humanos , Aneurisma Intracraniano/epidemiologia , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
15.
Nucleic Acids Res ; 48(D1): D789-D796, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31665503

RESUMO

The early detection of cancer holds the key to combat and control the increasing global burden of cancer morbidity and mortality. Blood-based screenings using circulating DNAs (ctDNAs), circulating RNA (ctRNAs), circulating tumor cells (CTCs) and extracellular vesicles (EVs) have shown promising prospects in the early detection of cancer. Recent high-throughput gene expression profiling of blood samples from cancer patients has provided a valuable resource for developing new biomarkers for the early detection of cancer. However, a well-organized online repository for these blood-based high-throughput gene expression data is still not available. Here, we present BBCancer (http://bbcancer.renlab.org/), a web-accessible and comprehensive open resource for providing the expression landscape of six types of RNAs, including messenger RNAs (mRNAs), long noncoding RNAs (lncRNAs), microRNAs (miRNAs), circular RNAs (circRNAs), tRNA-derived fragments (tRFRNAs) and Piwi-interacting RNAs (piRNAs) in blood samples, including plasma, CTCs and EVs, from cancer patients with various cancer types. Currently, BBCancer contains expression data of the six RNA types from 5040 normal and tumor blood samples across 15 cancer types. We believe this database will serve as a powerful platform for developing blood biomarkers.

16.
Tob Control ; 29(2): 191-199, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31073096

RESUMO

BACKGROUND: Lung cancer is substantially attributable to smoking, but detailed related estimates on smoking-attributable expenditure (SAE) in China are not available yet, which could inform tobacco control and cancer prevention initiatives. METHODS: A prevalence-based approach was adopted to estimate the total SAE, including direct expenditure (medical and non-medical) and indirect cost (disability and premature death). Detailed per-patient data on direct expenditure and work-loss days were acquired from a unique multicentre survey in China. Other parameters were from literatures and official reports. RESULTS: The total estimated SAE of lung cancer was US$5249 million in China in 2015 (0.05 % of gross domestic product for China). The estimated direct SAE was US$1937 million (36.9 % of the total SAE), accounting for 0.29 % of total healthcare expenditure for China. The medical and non-medical direct expenditures were US$1749 million and US$188 million, respectively. The estimated indirect cost was US$3312 million (63.1 % of the total SAE), including US$377 million due to disability and US$2935 million due to premature death. The SAE increased with age, peaking at 60-64 years (US$1004 million), and was higher among men, in urban areas and in eastern China. If smoking prevalence was reduced to 20%, as is the goal of Healthy China 2030, the total SAE would be decreased by 4.9 %. CONCLUSIONS: Smoking-attributable economic burden caused by lung cancer was substantial in China in 2015, and will continue increasing given current trends in lung cancer. However, future economic burden can be prevented with implementation of effective tobacco control and other interventions.

17.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3777-3786, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833691

RESUMO

The compensation effect of re-watering after drought has been widely reported in various crops during different growth stages. It is considered as an important self-regulation mechanism for plants to resist abiotic stresses and also an efficient utilization of limited water resource. In this study, two rounds of re-watering after drought treatments were carried out during tuber expansion period of potato, to investigate the drought threshold of potato and explore the potential mechanisms of compensation effect with source-sink aspect. We used virus-free plantlets of "Atlantic" potato as experimental materials. Four treatments were included: sufficient water supply (W), re-watering after mild drought (D1-W), re-watering after medium drought (D2-W) and re-watering after severe drought (D3-W). The results showed that potato yield exhibited an over-compensation effect after two rounds of D1-W treatment, with water use efficiency and yield being increased by 17.5% and 6.3%, respectively, compared with the sufficient water supply. D2-W treatment had no significant effect on potato yield, but water use efficiency was increased by 8.4%, indicating a near-equivalent compensation effect. On the contrary, D3-W treatment did not show any compensation effect in yield. In addition, leaf chlorophyll content, net photosynthetic rate, and leaf area were all reduced after drought treatment, indicating a reduction in "source" size and activity. After re-watering, D1-W and D2-W treatments showed over-compensation and compensation effects through improving source supply capacity. Meanwhile, re-watering after moderate drought increased the sink activity through significantly enhancing the activities of key enzymes in tubers (sink), thus increased the average weight of tubers. In conclusion, re-watering after moderate drought stress during potato tuber expansion period had compensation and over-compensation effects on both source and sink, and thus could compensate for the drought-induced yield loss and improve water use efficiency.


Assuntos
Solanum tuberosum , Secas , Fotossíntese , Tubérculos , Água
19.
Dermatol Ther ; : e13207, 2019 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-31885155

RESUMO

Verruca plana is a kind of benign proliferative skin disease that generally occurs in exposed parts, but the treatment of warts poses a therapeutic challenge for physicians, as there is no method, among numerous approaches, that has been proven effective for completely curing this disease. We report a case of verruca plana cured by narrow-band ultraviolet B (NB-UVB), which provides a new treatment of verruca plana.

20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(5): 731-736, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31762246

RESUMO

OBJECTIVE: To develop a method for detecting nicotine and cotinine in hair by hydrophilic interaction chromatography tandem mass spectrometry. METHODS: Hair samples were hydrolyzed in sodium hydroxide solution before extraction with dichloromethane. The samples were blown to dry with nitrogen and dissolved with mobile phase. The filtrate of the samples was injected into a chromatographic-mass spectrometry system for analysis. The separation was performed by a hydrophilic column, with which methanol-0.1% ammonia was used as the mobile phase. The quantitative detection of Nicotine and Cortinine was carried out with electron spray ionization-triple quadrupole mass spectrometry. The established method was used for detecting nicotine and cotinine in 602 hair samples of pregnant women and 31 hair and urine samples of volunteers. RESULTS: A standard curve was drawn for the established method of hydrophilic liquid chromatography tandem mass spectrometry. Good linearity was obtained for detecting nicotine and cotinine in the range of 0.030-100.000 µg/L, with a detection limit (MDL) of 0.007 6 µg/g and 0.004 4 µg/g, respectively. The inter-day and intra-day precisions reached a level of less than 10%. The recoveries of the spiked samples ranged from 81.0% to 102.0%. About 0.020-0.260 µg/g nicotine and 0.004 8-0.069 0 µg/g cotinine were detected in the pregnant women without exposure to secondhand smoking (SHS), compared with 0.029-0.350 µg/g nicotine and 0.005 6-0.085 0 µg/g cotinine in those exposed to SHS. Nicotine and cotinine were also found in the hair and urine samples of volunteers, which were correlated with smoking (P < 0.05). A dose-response relationship were found between smoking and hair nicotine. CONCLUSIONS: The proposed method is accurate and sensitive for detecting nicotine and cotinine in hair samples. Hair nicotine can be a specific biomarker for assessing exposure to tobacco smoking.


Assuntos
Cotinina/análise , Cabelo/química , Nicotina/análise , Biomarcadores/análise , Cromatografia Líquida , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Gravidez , Espectrometria de Massas em Tandem , Poluição por Fumaça de Tabaco
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