Melatonin modulates adiponectin expression on murine colitis with sleep deprivation

AIM To determine adiponectin expression in colonic tissue of murine colitis and systemic cytokine expression after melatonin treatments and sleep deprivation.METHODS The following five groups of C57BL/6 mice were used in this study:(1) group Ⅰ,control;(2) group Ⅱ,2% DSS induced colitis for 7 d;(3) group Ⅲ,2% DSS induced colitis and melatonin treatment;(4) group Ⅳ,2% DSS induced colitis with sleep deprivation(SD) using specially designed and modified multiple platform water baths; and(5) group V,2% DSS induced colitis with SD and melatonin treatment. Melatonin(10 mg/kg) or saline was intraperitoneally injected daily to mice for 4 d. The body weight was monitored daily. The degree of colitis was evaluated histologically after sacrificing the mice. Immunohistochemical staining and Western blot analysis was performed using anti-adiponectin antibody. After sampling by intracardiac punctures,levels of serum cytokines were measured by ELISA. RESULTS Sleep deprivation in water bath exacerbated DSS induced colitis and worsened weight loss. Melatonin injection not only alleviated the severity of mucosal injury,but also helped survival during stressful condition. The expression level of adiponectin in mucosa was decreased in colitis,with the lowest level observed in colitis combined with sleep deprivation. Melatonin injection significantly(P < 0.05) recovered the expression of adiponectin. The expression levels of IL-6 and IL-17 were increased in the serum of mice with DSS colitis but decreased after melatonin injection. CONCLUSION This study suggested that melatonin modulated adiponectin expression in colonic tissue and melatonin and adiponectin synergistically potentiated antiinflammatory effects on colitis with sleep deprivation.

Learning Discriminatory Information for Object Detection on Urine Sediment Image

In clinical practice,the microscopic examination of urine sediment is considered an important in vitro examination with many broad applications.Measuring the amount of each type of urine sediment allows for screening,diagnosis and evaluation of kidney and urinary tract disease,providing insight into the specific type and severity.However,manual urine sediment examination is labor-intensive,time-consuming,and subjective.Traditional machine learning based object detection methods require hand-crafted features for localization and classification,which have poor generalization capabilities and are difficult to quickly and accurately detect the number of urine sediments.Deep learning based object detection methods have the potential to address the challenges mentioned above,but these methods require access to large urine sediment image datasets.Unfortunately,only a limited number of publicly available urine sediment datasets are currently available.To alleviate the lack of urine sediment datasets in medical image analysis,we propose a new dataset named UriSed2K,which contains 2465 high-quality images annotated with expert guidance.Two main challenges are associated with our dataset:a large number of small objects and the occlusion between these small objects.Our manuscript focuses on applying deep learning object detection methods to the urine sediment dataset and addressing the challenges presented by this dataset.Specifically,our goal is to improve the accuracy and efficiency of the detection algorithm and,in doing so,provide medical professionals with an automatic detector that saves time and effort.We propose an improved lightweight one-stage object detection algorithm called Discriminatory-YOLO.The proposed algorithm comprises a local context attention module and a global background suppression module,which aid the detector in distinguishing urine sediment features in the image.The local context attention module captures context information beyond the object region,while the global background suppression module emphasizes objects in uninformative backgrounds.We comprehensively evaluate our method on the UriSed2K dataset,which includes seven categories of urine sediments,such as erythrocytes(red blood cells),leukocytes(white blood cells),epithelial cells,crystals,mycetes,broken erythrocytes,and broken leukocytes,achieving the best average precision(AP)of 95.3%while taking only 10 ms per image.The source code and dataset are available at https://github.com/binghuiwu98/discriminatoryyolov5.

Measurement of very low-molecular weight metabolites by traveling wave ion mobility and its use in human urine samples

The collision cross-sections(CCS)measurement using ion mobility spectrometry(IMS)in combination with mass spectrometry(MS)offers a great opportunity to increase confidence in metabolite identification.However,owing to the lack of sensitivity and resolution,IMS has an analytical challenge in studying the CCS values of very low-molecular-weight metabolites(VLMs250 Da).Here,we describe an analytical method using ultrahigh-performance liquid chromatography(UPLC)coupled to a traveling wave ion mobility-quadrupole-time-of-flight mass spectrometer optimized for the measurement of VLMs in human urine samples.The experimental CCS values,along with mass spectral properties,were reported for the 174 metabolites.The experimental data included the mass-to-charge ratio(m/z),retention time(RT),tandem MS(MS/MS)spectra,and CCS values.Among the studied metabolites,263 traveling wave ion mobility spectrometry(TWIMS)-derived CCS values(TWCCSN2)were reported for the first time,and more than 70%of these were CCS values of VLMs.The TWCCSN2 values were highly repeatable,with inter-day variations of<1%relative standard deviation(RSD).The developed method revealed excellent TWCCSN2 accuracy with a CCS difference(DCCS)within±2%of the reported drift tube IMS(DTIMS)and TWIMS CCS values.The complexity of the urine matrix did not affect the precision of the method,as evidenced by DCCS within±1.92%.According to the Metabolomics Standards Initiative,55 urinary metabolites were identified with a confidence level of 1.Among these 55 metabolites,53(96%)were VLMs.The larger number of confirmed compounds found in this study was a result of the addition of TWCCSN2 values,which clearly increased metabolite identification confidence.

Landscape of urine biomarkers for bladder cancer:molecular function,cell-of-origin,and bibliometric trend

Background:The effective management of bladder cancer(BCa)depends on the early diagnosis and surveillance.Previous studies have explored numerous urinary molecules as potential biomarkers of BCa.However,the molecular functions and cell-of-origin profiles of these biomarkers are yet to be elucidated.In this study,we aimed to provide a comprehensive overview of the landscape of urinary biomarker genes for BCa.Methods:We conducted an exhaustive literature search in PubMed,through which 555 biomarker genes were identified.We then analyzed the BCa single-cell atlas to infer the cellular origin of these BCa urine biomarker genes and performed functional enrichment analysis to gain insights into the functional molecular implications of these biomarkers.Results:These genes are involved in tumor proliferation,angiogenesis,cellmigration,and cell death and are predominantly expressed in epithelial and stromal cells.Interestingly,our analysis ofmultiomics tumor data revealed a discordance between tissue and urine in terms of differential methylation and RNA expression,suggesting that biomarker discovery for liquid biopsies should ideally begin with the analysis of bodily fluids rather than relying interest and that test strategies incorporating multiple molecular markers represent an ongoing trend.Conclusions:Collectively,our study has built a landscape of BCa urine biomarker genes,uncovered molecular insights into these biomarkers,and revealed the bibliometric trends in this field,which will contribute to the discovery of novel biomarkers in the future.

影响Urine-H-11干化学法检测尿液分析的因素

Urine—H—11尿液试纸是干化学法检测尿液分析的一种方法，利用干化学法进行尿液分析，能够简便，快速为临床诊断、治疗、预防和监测疾病提供可靠的实验依据，但是，Urine—H—11干化学法也受许多因素的影响，而导致结果的准确性，为了使大家更多的了解影响Urine-H—11干化学法检测尿液的各项因素，准确的为临床提供诊断依据，现将有关Urine—H—11干化学法检测尿液的影响因素总结如下：

Detection of Neisseria Gonorrhoeae from Urine with Ligase Chain Reaction

Objective: To evaluate the value of ligase chainreaction(LCR) in the diagnosis of diplococcusgonorrhoeae in urine. Methods: LCR detection of the urine for Neisseriagonorrhoeae and bacteria culture of discharge was per-formed simultaneously to 276 patients with urethritisor cervicitis seeking treatment in sex transmitted dis-eases (STDs) outpatient clinic. For specimens withdiscordant results, polymerase chain reaction wasconducted. The purpose was to detect the respectivesensitivity and specificity of bacteria culture and LCR. Results: 24 of 276(8.7%) patients had positive LCRresults and 21 of 276(7.6%) were positive for culture.5 specimens had discordant results from LCR andbacteria culture. The sensitivity and specificity of LCRin the diagnosis of gonorrhoeae were 92.3% and100% respectively. Conclusion: This study showed that LCR had ahigher sensitivity and specificity for the diagnosis ofgonorrhoeae from urine.

Oxidative stress and lipid peroxidation products:effect of pinealectomy or exogenous melatonin injections on biomarkers of tissue damage during acute pancreatitis

BACKGROUND:Melatonin (N-acetyl-5-methoxytripta-mine) is a free radical scavenger and a strong antioxidant,secreted by the pineal gland.In this study,we evaluated the effects of decreasing and increasing serum melatonin levels on malonyldialdehyde (MDA),superoxide dismutase (SOD),and reduced glutathione (GSH) levels in pancreatic tissue from rats with experimental acute pancreatitis.METHODS:Experimental acute pancreatitis was induced in three groups of Wistar albino rats (10 animals per group) by pancreatic ductal ligation.The first group had only acute pancreatitis and served as the control.Surgical pinealectomy was added to acute pancreatitis in the second group,removing the source of endogenous melatonin (low melatonin levels group).The third group was given 0.1 ml daily intraperitoneal injections of 20 mg/ml melatonin solution for one week (high melatonin levels group).The effects of melatonin levels were evaluated by comparison of the levels of MDA,SOD,and GS in pancreatic tissue.RESULT:We found that intraperitoneal melatonin injections decreased the levels of MDA and increased the levels of SOD and GSH in pancreatic tissue.CONCLUSION:Exogenous melatonin has a preventive effect on lipid peroxidation and oxidative damage in acute pancreatitis.

Determination of urine catecholamines and metanephrines by reversed-phase liquid chromatography-tandem mass spectrometry

The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines.

A Study on Bisphenol A,Nonylphenol,and Octylphenol in Human Urine amples Detected by SPE-UPLC-MS

Objective To establish a comprehensive analytical method based on SPE‐UPLC‐MS for the simultaneous determination of bisphenol A （BPA）, nonylphenol （NP）, and octylphenol （OP） in urine samples. Methods Sixty urine samples collected from healthy subjects were analyzed for BPA, NP, and OP concentrations. The samples were de‐conjugated by adding β‐glucuronidase and sulfatase. After the enzymatic treatment, the samples were subjected to the OASIS HLB column solid phase extraction cartridges so as to be cleaned and concentrated. The UPLC separation was performed on a Acquity UPLCTM BEH C18 column （2.1×100 mm, 1.7 μm） with a gradient elution system of methanol‐water as the mobile phase. Triple‐quadrupole mass spectrometry analyzer was used for the qualitative and quantitative analysis of UPLC‐MS/MS system. Results The limit of detection of BPA, NP, and OP was 0.10, 0.10, and 0.15 ng/mL, respectively. The recoveries of BPA, NP and OP were 80.1%‐108%, 81.3%‐109%, and 81.5%‐98.7%, respectively. Among the 60 urine samples, BPA was detected in 8 samples at the level of 0.297‐32.7ng/mL, NP was detected in 29 samples at the level of 1.69‐27.8 ng/mL, and OP was detected in 17 samples at the level of 0.407‐11.1 ng/mL. Conclusion The method is simple with high sensitivity and selectivity, and is suitable for the determination of BPA, NP, and OP in urine. As shown by our analysis , BPA, NP, and OP appear to be prevalent in human urine. This is particularly true for NP. The results from our study is therefore valuable for future studies to assess the exposure to BPA, NP, and OP in the general population.

Simultaneous determination of fluorine and iodine in urine by ion chromatography with electrochemical pretreatment

A new method for the simultaneous determination of fluorine and iodine in urine by ion chromatography （IC） with electrochemical pretreatment has been developed. The pretreatment was performed in a novel electrochemical oxidationneutralization device （EOND）, in which iodide of the sample was oxidized to iodate and the alkaline digestion sample solution was neutralized. Under the optimized conditions, the limits of detection （LOD, S/N = 3） were 2.5 μg/L for fluoride and 20 μg/L for iodate, respectively. The recoveries were in the range of 93-102% for fluoride and 86-98% for iodate.

急性呼吸窘迫综合征患儿血清Melatonin、MIP-1α与NLRP3炎症小体和预后的关系分析

目的探讨急性呼吸窘迫综合征(ARDS)患儿血清褪黑素(Melatonin)、巨噬细胞炎性蛋白-1α(MIP-1α)与核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)炎症小体和预后的关系。方法选取2021年1月至2023年1月该院收治的ARDS患儿140例纳入ARDS组,另选取同期100例体检健康儿童纳入对照组。根据入院28 d临床结局将ARDS患儿分为死亡组29例和存活组111例。采用酶联免疫吸附试验检测血清Melatonin、MIP-1α、白细胞介素(IL)-1β、IL-18水平,实时荧光定量PCR检测NLRP3 mRNA、半胱氨酸蛋白酶-1(Caspase-1)mRNA水平。采用Pearson相关分析ARDS患儿血清Melatonin、MIP-1α水平与NLRP3炎症小体相关指标(NLRP3 mRNA、Caspase-1 mRNA、IL-1β、IL-18)的相关性。采用多因素Cox回归分析影响ARDS患儿预后的因素。根据ARDS患儿血清Melatonin、MIP-1α水平均值分为高/低血清Melatonin、MIP-1α组,Kaplan-Meier法绘制高/低血清Melatonin、MIP-1α水平ARDS患儿生存曲线。采用受试者工作特征(ROC)曲线分析血清Melatonin、MIP-1α对ARDS患儿死亡的预测价值。结果与对照组比较,ARDS组血清Melatonin水平降低,血清MIP-1α、IL-1β、IL-18和外周血单核细胞NLRP3 mRNA、Caspase-1 mRNA水平升高(P<0.05)。Pearson相关分析显示,ARDS患儿血清Melatonin水平与NLRP3 mRNA、Caspase-1 mRNA、IL-1β、IL-18均呈负相关(P<0.05),MIP-1α水平与NLRP3 mRNA、Caspase-1 mRNA、IL-1β、IL-18均呈正相关(P<0.05)。多因素Cox回归分析显示,急性生理学和慢性健康状况评价Ⅱ评分、NLRP3 mRNA、Caspase-1 mRNA、IL-1β、IL-18、MIP-1α为影响ARDS患儿预后的独立危险因素,Melatonin为独立保护因素(P<0.05)。Kaplan-Meier生存曲线分析显示,高血清Melatonin组28 d生存率高于低血清Melatonin组(P<0.05),高血清MIP-1α组28 d生存率低于低血清MIP-1α组(P<0.05)。ROC曲线分析显示,血清Melatonin、MIP-1α联合预测ARDS患儿死亡的曲线下面积为0.881(95%CI 0.816~0.930),大于血清Melatonin、MIP-1α单独预测的0.785(95%CI 0.708~0.850)、0.778(95%CI 0.700~0.844)。结论ARDS患儿血清Melatonin水平降低、MIP-1α水平升高,与NLRP3炎症小体和预后密切相关,联合检测血清Melatonin、MIP-1α水平对ARDS患儿预后具有较高的预测价值。

Urea hydrolysis and recovery of nitrogen and phosphorous as MAP from stale human urine

Laboratory-scale tests for magnesium ammonium phosphate（MAP）precipitation following urea hydrolysis of human urine were conducted using orthogonal experiment design.The effects of initial pH,temperature and the volumetric ratios of stale urine to fresh urine,on urea hydrolysis in urine were studied to determine the final hydrolysis time to recover most nitrogen from separated human urine by MAP.With a volumetric ratio of stale to fresh urine>10% and at temperature≥20℃,urea hydrolysis could be completed in two days.Alkaline pH inhibited urea hydrolysis progress.The final pH values were all around 9.0 following urine hydrolysis,while the suspension pH might act as an indicator to detect the start and extent of urea hydrolysis.Over 95% of ammonium nitrogen and over 85% of phosphorus from hydrolyzed urine as MAP precipitate were obtained using MgCl;·6H;O and Na;HPO;·12H;O as precipitation agents at pH 8.5,molar ratio of Mg;:NH;-N:PO;-P at（1.2-1.3）:1:1,mixing speed of 120 r/min,and precipitation time and reaction time of 3 h and 15 min,respectively.The precipitate has a structure resembling pure MAP crystal.

Nuclear magnetic resonance-based metabolomics and metabolic pathway networks from patient-matched esophageal carcinoma,adjacent noncancerous tissues and urine

BACKGROUND Several studies have demonstrated a correlation between esophageal cancer(EC)and perturbed urinary metabolomic profiles,but none has described the correlation between urine metabolite profiles and those of the tumor and adjacent esophageal mucosa in the same patient.AIM To investigate how urinary metabolic phenotypes were linked to the changes in the biochemical landscape of esophageal tumors.METHODS Nuclear magnetic resonance-based metabolomics were applied to esophageal tumor tissues and adjacent normal mucosal tissues alongside patient-matched urine samples.RESULTS Analysis revealed that specific metabolite changes overlapped across both metrics,including glucose,glutamate,citrate,glycine,creatinine and taurine,indicating that the networks for metabolic pathway perturbations in EC,potentially involved in but not limited to disruption of fatty acid metabolism,glucose and glycolytic metabolism,tricarboxylic acid cycle and glutaminolysis.Additionally,changes in most urinary biomarkers correlated with changes in biomarker candidates in EC tissues,implying enhanced energy production for rapid cell proliferation.CONCLUSION Overall,these associations provide evidence for distinct metabolic signatures and pathway disturbances between the tumor tissues and urine of EC patients,and changes in urinary metabolic signature could reflect reprogramming of the aforementioned metabolic pathways in EC tissues.Further investigation is needed to validate these initial findings using larger samples and to establish the underlying mechanism of EC progression.

Urine versus brushed samples in human papillomavirus screening： study in both genders

Aim： To investigate whether urine is a good medium for screening and whether there is a correlation between the amount of extracted DNA and human papillomavirus （HPV）-positivity. Methods： In the present study, 30 first-voided urine （FVU） specimens and 20 urethroglandular swabs using cervex-brushes from male partners of HPV-positive patients, and 31 FVU specimens and 100 liquid-based cervix cytology leftovers sampled with cervix-brushes from HPV-positive women were examined for the presence of β-globin. Oncogenic HPV were detected using type-specific PCR. Results： β-globin was found in all the brushed samples, whereas it was found in only 68.9% of the FVU specimens. HPV-PCR was positive in 60.0% of the male brushes, in 29% of the female brushes and in 0% of the male FVU specimens. DNA concentration was, respectively, 0.9998 ng/μL, 37.0598 ng/μL and 0.0207 ng/μL. Conclusion： Urine is not a good tool for HPV detection, probably because the low DNA concentration reflects a low amount of collected cells. β-globin is measurable in FVU by real time quantitative PCR, but the DNA concentration is lower compared to brush sampling for both genders. β-globin-positivity of urethral and cervical swabs is 100%, showing a higher mean concentration of DNA, leading to a higher detection rate of HPV. This is the first article linking DNA- concentration to the presence of HPV.

Inhibition of mitochondria responsible for the anti-apoptotic effects of melatonin during ischemia-reperfusion

Objective： To investigate a possible mechanism responsible for anti-apoptotic effects of melatonin and provide theoretical evidences for clinical therapy. Methods： lschemia-reperfusion mediated neuronal cell injury model was constructed in cerebellar granule neurons （CGNs） by deprivation of glucose, serum and oxygen in media. After ischemia, melatonin was added to the test groups to reach differential concentration during reperfusion. DNA fragmentation, mitochondrial transmembrane potential, mitochondrial cytochrome c release and caspase-3 activity were observed after subjecting cerebellar granule neurons to oxygen-glucose deprivation （OGD）. Results： The results showed that OGD induced typical cell apoptosis change, DNA ladder and apoptosis-related alterations in mitochondrial functions including depression of mitochondrial transmembrane potential （its maximal protection ratio was 73.26%） and release of cytochrome c （its maximal inhibition ratio was 42.52%） and the subsequent activation of caspase-3 （its maximal protection ratio was 59.32%） in cytoplasm. Melatonin reduced DNA damage and inhibited release of mitochondrial cytochrome c and activation of caspase-3. Melatonin can strongly prevent the OGD-induced loss of the mitochondria membrane potential. Conclusion： Our findings suggested that the direct inhibition of mitochondrial pathway might essentially contribute to its anti-apoptotic effects in neuronal ischemia-reperfiusion.

Protective Effect of Distillate and Redistillate of Cow’s Urine in Human Polymorphonuclear Leukocytes Challenged With Established Genotoxic Chemicals

Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects.

Measurement of Orotic Acid in Urine by Supercritical Fluid Chromatography

This work presents a simple, rapid and reliable supercritical fluid chromatography (SFC) method for a sensitive measurement of orotic acid in human urine. The samples were diluted with deionized water and analyzed directly without any pretreatment.

Dispersive Liquid-liquid Microextraction Combined with High-performance Liquid Chromatography for the Determination of Clozapine and Chlorpromazine in Urine

A simple method has been proposed for the determination of clozapine （CLZ） and chlorpromazine （CPZ） in human urine by dispersive liquid-liquid microextraction （DLLME） in combination with high-performance liquid chromatography-ultraviolet detector （HPLC-UV）. All important variables influencing the extraction efficiency, such as pH, types of the extraction solvent and the disperser solvent and their volume, ionic strength and centrifugation time were investigated and optimized. Under the optimal conditions, the limit of detection （LODs） and quantification （LOQs） of the method were 13 and 39 ng/mL for CLZ, and 2 and 6 ng/mL for CPZ, respectively. The relative standard deviations （RSDs） of the targets were less than 5.1% （C=0.100 μg/mL, n=9）. Good linear behaviors over the tested concentration ranges were obtained with the values of R20.999 for the targets. The absolute extraction efficiencies of CLZ and CPZ from the spiked blank urine samples were 98.3% and 97.8%, respectively. The applicability of the technique was validated by analyzing urine samples and the mean recoveries for spiked urine samples ranged from 93.3% to 105.0%. The method was successfully applied for the determination of CLZ and CPZ in real human urine.

Early diagnosis and prediction of severity in acute pancreatitis using the urine trypsinogen-2 dipstick test:A prospective study

AIM： To evaluate the use of the trypsinogen-2 dipstick （Actim Pancreatitis） test for early diagnosis and prediction of severity in acute pancreatitis （AP）. METHODS： Ninety-two patients with AP were included in this study. The control group was 25 patients who had acute abdominal pain from non-pancreatic causes. Urine trypsinogen-2 dipstick test （UTDT） and conventional diagnostic tests were performed in all patients. Patients were divided by the Atlanta classification into two groups as having mild or severe pancreatitis. RESULTS： UTDT was positive in 87 （94.6%） of the AP patients and in two （8%） controls （P 〈 0.05）. Positive UTDT was found in 61 （92.4%） of 66 （71.7%） patients with mild pancreatitis and in all （100%） of the 26 （28.3%） with severe pancreatitis （P 〉 0.05）. UTDT positivity lasted longer in severe pancreatitis compared with that in mild pancreatitis （6.2 ＋ 2.5 d vs 2.0 ＋ 1.43 d, P 〈 0.05）. The sensitivity, specificity, positive predictive value, negative predictive value （NPV）, positive likelihood ratio （PLR） and negative likelihood ratio （NLR） of UTDT were 91%, 72%, 96.6%, 70.4%, 3.4 and 0.1, respectively. CONCLUSION： UTDT is a simple, rapid and reliable method for use on admission. It has high specificity and low NLR for early diagnosis and prediction of severity in AP. However, its relatively low NPV does not allow trypsinogen-2 dipstick test to be a stand-alone tool for diagnosis of acute pancreatitis; the use of other conventional diagnostic tools remains a requirement.

Science Letters:Culture of Spirulina platensis in human urine for biomass production and O_2 evolution

Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O2 evolution, for potential application to nutrient regeneration and air revitalization in life support system. The culture results showed that Spirulinaplatensis grows successfully in diluted human urine, and yields maximal biomass at urine dilution ratios of 140-240. Accumulation of lipid and decreasing of protein occurred due to N deficiency. O2 release rate of Spirulina platensis in diluted human urine was higher than that in Zarrouk medium.