自然流产患者的卵泡液代谢标志物研究

目的探讨与自然流产发生相关的卵泡液(FF)代谢标志物,以进一步科学阐释自然流产的发生机制。方法利用超高效液相色谱-高分辨质谱技术对因输卵管因素行体外受精-胚胎移植(IVF-ET)后自然流产患者即流产组(40例)及分娩者即对照组(45例)的FF进行代谢组学分析。结果流产组和对照组FF共32种差异代谢物,主要有氨基酸类、胆固醇类、维生素类、脂肪酸类、胆酸类、溶血卵磷脂类及其他7大类,其中上调的有Dehydroepiandrosterone sulfate,Lyso PC(16∶0),Palmitoylglycerophosphocholine等8种,下调的有L-valine,6-Oxohexanoate,L-Phenylalanine,2-Oxoglutarate,Linoleate等24种。结论本研究鉴定的32种差异代谢物与自然流产相关,为自然流产提供可能的诊断依据和治疗靶点,从FF代谢组学层面为阐释自然流产发生机制提供科学依据。

基于卵泡液代谢组学的卵巢低反应生物标志物研究

目的通过卵泡液代谢组学探寻与卵巢低反应相关的生物标志物。方法采用超高液相色谱-高分辨质谱联用仪对行体外受精-胚胎移植/单精子卵泡浆内显微注射-胚胎移植(IVF-ET/ICSI-ET)的卵巢低反应组30例,以及同时仅因男方因素行IVF-ET/ICSI-ET的对照组49例进行卵泡液代谢组学分析。对比两组的差异代谢物。结果与卵巢低反应相关的潜在生物标志物有30种,其上调的代谢物有9种,包括L-苯丙氨酸、脯氨酸、色氨酸、1-羟基-2-氧代丙基四氢蝶呤、水杨酸镁、尿苷二磷酸、LysoPC(18∶1)、LysoPC(18∶2)及LysoPC(18∶3);下调的代谢物有21种,包括6-氧代己酸酯、亚油酸酯、油酸、十六烷、花生四烯酸、二十二碳六烯酸、13,14-二氢视黄醇、石胆酸、7-脱氢甾醇、硬脂酰肉碱、25-羟基维生素D3、27-羟基胆固醇、3α,7α,12α-三羟基-5β-胆甾烷、13-羟基-α-生育酚、强啡肽A、LysoPC(16∶1)、LysoPC(16∶0)、LysoPC(18∶0)、LysoPC(20∶5)、LysoPC(20∶4)、LysoPC(20∶3)。结论卵巢低反应患者在卵巢储备、卵巢反应、卵子数目、质量方面比正常女性低;卵巢低反应患者卵泡液代谢物与正常女性比较,差异有统计学意义(P <0.05)。这些差异代谢物可以作为卵巢低反应的生物标志物。

Laparoscopic VS open hepatectomy for hepatolithiasis: An updated systematic review and meta-analysis

AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane Library,and undertook a meta-analysis to compare the efficacy and safety of laparoscopic hepatectomy V S conventional open liver resection for local hepatolithiasis in the left or right lobe. Intraoperative and postoperative outcomes(time,estimated blood loss,blood transfusion rate,postoperative intestinal function recovery time,length of hospital stay,postoperative complication rate,initial residual stone,final residual stone and stone recurrence) were analyzed systematically.RESULTS A comprehensive literature search retrieved 16 publications with a total of 1329 cases. Meta-analysis of these studies showed that the laparoscopic approach for hepatolithiasis was associated with significantly less intraoperative estimated blood loss [weighted mean difference(WMD): 61.56,95% confidence interval(CI): 14.91-108.20,P = 0.01],lower blood transfusion rate [odds ratio(OR): 0.41,95%CI: 0.22-0.79,P = 0.008],shorter intestinal function recovery time(WMD: 0.98,95%CI: 0.47-1.48,P = 0.01),lower total postoperative complication rate(OR: 0.52,95%CI: 0.39-0.70,P < 0.0001) and shorter stay in hospital(WMD: 3.32,95%CI: 2.32-4.32,P < 0.00001). In addition,our results showed no significant differences between the two groups in operative time(WMD: 21.49,95%CI: 0.27-43.24,P = 0.05),residual stones(OR: 0.79,95%CI: 0.50-1.25,P = 0.31) and stone recurrence(OR: 0.34,95%CI: 0.11-1.08,P = 0.07). Furthermore,with subgroups analysis,our results proved that the laparoscopic approach for hepatolithiasis in the left lateral lobe and left side could achieve satisfactory therapeutic effects. CONCLUSION The laparoscopic approach is safe and effective,with less intraoperative estimated blood loss,fewer postoperative complications,reduced length of hospital stay and shorter intestinal function recovery time than with conventional approaches.

The role of Rho/Rho-kinase pathway and the neuroprotective effects of fasudil in chronic cerebral ischemia

The Rho/Rho-kinase signaling pathway plays an important role in cerebral ischemia/reperfusion injury. However, very few studies have examined in detail the changes in the Rho/Rho-kinase signaling pathway in chronic cerebral ischemia. In this study, rat models of chronic cerebral ischemia were established by permanent bilateral common carotid artery occlusion and intra- gastrically administered 9 mg/kg fasudil, a powerful ROCK inhibitor, for 9 weeks. Morris water maze results showed that cognitive impairment progressively worsened as the cerebral ischemia proceeded. Immunohistochemistry, semi-quantitative RT-PCR and western blot analysis showed that the expression levels of Rho-kinase, its substrate myosin-binding subunit, and its relat- ed protein alpha smooth muscle actin, significantly increased after chronic cerebral ischemia. TUNEL staining showed that chronic cerebral ischemia could lead to an increase in neuronal apoptosis, as well as the expression level of caspase-3 in the frontal cortex of rats subjected to chronic cerebral ischemia. Fasudil treatment alleviated the cognitive impairment in rats with chronic cerebral ischemia, and decreased the expression level of Rho-kinase, myosin-binding subunit and alpha smooth muscle actin. Furthermore, fasudil could regulate cerebral injury by reducing cell apoptosis and decreasing caspase-3 expression in the frontal cortex. These findings demonstrate that fasudil can protect against cognitive impairment induced by chronic cerebral ischemia via the Rho/Rho-kinase signaling pathway and anti-apoptosis mechanism.

Intranasal insulin ameliorates neurological impairment after intracerebral hemorrhage in mice

In Alzheimer’s disease and ischemic stroke,intranasal insulin can act as a neuroprotective agent.However,whether intranasal insulin has a neuroprotective effect in intracerebral hemorrhage and its potential mechanisms remain poorly understood.In this study,a mouse model of autologous blood-induced intracerebral hemorrhage was treated with 0.5,1,or 2 IU insulin via intranasal delivery,twice per day,until 24 or 72 hours after surgery.Compared with saline treatment,1 IU intranasal insulin treatment significantly reduced hematoma volume and brain edema after cerebral hemorrhage,decreased blood-brain barrier permeability and neuronal degeneration damage,reduced neurobehavioral deficits,and improved the survival rate of mice.Expression levels of p-AKT and p-GSK3βwere significantly increased in the perihematoma tissues after intranasal insulin therapy.Our findings suggest that intranasal insulin therapy can protect the neurological function of mice after intracerebral hemorrhage through the AKT/GSK3βsignaling pathway.The study was approved by the Ethics Committee of the North Sichuan Medical College of China(approval No.NSMC(A)2019(01))on January 7,2019.

Astrocyte-neuron communication mediated by the Notch signaling pathway:focusing on glutamate transport and synaptic plasticity

Maintaining glutamate homeostasis after hypoxic ischemia is important for synaptic function and neural cell activity,and regulation of glutamate transport between astrocyte and neuron is one of the important modalities for reducing glutamate accumulation.However,further research is needed to investigate the dynamic changes in and molecular mechanisms of glutamate transport and the effects of glutamate transport on synapses.The aim of this study was to investigate the regulatory mechanisms underlying Notch pathway mediation of glutamate transport and synaptic plasticity.In this study,Yorkshire neonatal pigs(male,age 3 days,weight 1.0–1.5 kg,n=48)were randomly divided into control(sham surgery group)and five hypoxic ischemia subgroups,according to different recovery time,which were then further subdivided into subgroups treated with dimethyl sulfoxide or a Notch pathway inhibitor(N-[N-(3,5-difluorophenacetyl-l-alanyl)]-S-phenylglycine t-butyl ester).Once the model was established,immunohistochemistry,immunofluorescence staining,and western blot analyses of Notch pathway-related proteins,synaptophysin,and glutamate transporter were performed.Moreover,synapse microstructure was observed by transmission electron microscopy.At the early stage(6–12 hours after hypoxic ischemia)of hypoxic ischemic injury,expression of glutamate transporter excitatory amino acid transporter-2 and synaptophysin was downregulated,the number of synaptic vesicles was reduced,and synaptic swelling was observed;at 12–24 hours after hypoxic ischemia,the Notch pathway was activated,excitatory amino acid transporter-2 and synaptophysin expression was increased,and the number of synaptic vesicles was slightly increased.Excitatory amino acid transporter-2 and synaptophysin expression decreased after treatment with the Notch pathway inhibitor.This suggests that glutamate transport in astrocytes-neurons after hypoxic ischemic injury is regulated by the Notch pathway and affects vesicle release and synaptic plasticity through the expression of synaptophysin.

Influence of control strategy on stability of dual-spin projectiles with fixed canards

Existing literature has shown that the control force at the nose could cause dynamic instability for controlled projectiles. To lower the adverse impact on the dual-spin projectile with fixed canards under the premise of meeting guidance system requirements, the influence of control moment provided by a motor on the flight stability is analyzed in this paper. Firstly, the effect of the rolling movement on stability is analyzed based on the stability criterion derived using the Hurwitz stability theory. Secondly, the evaluation parameters combining the features of different control periods that could assess the variation of stability features after the motor torque are obtained. These effective formulas are used to indicate that, to reduce the flight instability risks, the stabilized rolling speed of roll speed keeping period should be as small as possible; the variation trend of motor torque during the rolling speed controlling period and the roll angle of the forward body during roll angle switching period are recommended corresponding to the projectile and trajectory characteristics. Moreover,detailed numerical simulations of 155 mm dual-spin projectile are satisfactory agreement with the theoretical results.

Endothelial Nitric Oxide Synthase Gene Polymorphisms Associated with Susceptibility to High Altitude Pulmonary Edema in Chinese Railway Construction Workers at Qinghai-Tibet over 4500 Meters above Sea Level

Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.

Different techniques for harvesting grafts for living donor liver transplantation: A systematic review and meta-analysis

AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochrane Library were searched comprehensively for studies comparing MILDH with conventional living donor hepatectomy (CLDH). Intraoperative and postoperative outcomes (operative time, estimated blood loss, postoperative liver function, length of hospital stay, analgesia use, complications, and survival rate) were analyzed in donors and recipients. Articles were included if they: (1) compared the outcomes of MILDH and CLDH; and (2) reported at least some of the above outcomes. RESULTS Of 937 articles identified, 13, containing 1592 patients, met our inclusion criteria and were included in the meta-analysis. For donors, operative time [weighted mean difference (WMD) = 20.68, 95% CI: -6.25-47.60, p = 0.13] and blood loss (WMD = -32.61, 95% CI: -80.44-5.21, p = 0.18) were comparable in the two groups. In contrast, analgesia use (WMD = -7.79, 95% CI: -14.06-1.87, p = 0.01), postoperative complications [odds ratio (OR) = 0.62, 95% CI: 0.44-0.89, p = 0.009], and length of hospital stay (WMD): -1.25, 95% CI: -2.35-0.14, p = 0.03) significantly favored MILDH. No differences were observed in recipient outcomes, including postoperative complications (OR = 0.93, 95% CI: 0.66-1.31, p = 0.68) and survival rate (hr = 0.96, 95% CI: 0.27-3.47, p = 0.95). Funnel plot and statistical methods showed a low probability of publication bias. CONCLUSION MILDH is safe, effective, and feasible for living donor liver resection with fewer donor postoperative complications, reduced length of hospital stay and analgesia requirement than CLDH.

Influence of anions in phosphate and tetraborate electrolytes on growth kinetics of microarc oxidation coatings on Ti6Al4V alloy

The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.

Moving horizon based wavelet de-noising method of dual-observed geomagnetic signal for nonlinear high spin projectile roll positioning

Phase-frequency characte ristics of approximate sinusoidal geomagnetic signals can be used fo r projectile roll positioning and other high-precision trajectory correction applications.The sinusoidal geomagnetic signal deforms in the exposed and magnetically contaminated environment.In order to preciously recognize the roll information and effectively separate the noise component from the original geomagnetic sequence,based on the error source analysis,we propose a moving horizon based wavelet de-noising method for the dual-observed geomagnetic signal filtering where the captured rough roll frequency value provides reasonable wavelet decomposition and reconstruction level selection basis for sampled sequence;a moving horizon window guarantees real-time performance and non-cumulative calculation amount.The complete geomagnetic data in full ballistic range and three intercepted paragraphs are used for performance assessment.The positioning performance of the moving horizon wavelet de-noising method is compared with the band-pass filter.The results show that both noise reduction techniques improve the positioning accuracy while the wavelet de-noising method is always better than the band-pass filter.These results suggest that the proposed moving horizon based wavelet de-noising method of the dual-observed geomagnetic signal is more applicable for various launch conditions with better positioning performance.

Influence of yawing force frequency on angular motion and ballistic characteristics of a dual-spin projectile

A roll-decoupled course correction fuze with canards can improve the hit accuracy of conventional unguided ammunitions. The fuze increases accuracy by reducing the effect of angular and translational motion produced by the cyclical yawing forces applied on the projectile. In order to investigate the influence of yawing forces on angular motion, a theoretical solution of the total yaw angle function with the cyclical yawing forces is deduced utilizing the 7 degrees of freedom(7-DOF) model designed for this calculation. Furthermore, a detailed simulation is carried out to determine the influence rules of yawing force on angular motion. The calculated results illustrate that, when the rotational speed of the forward part is close to the initial turning rate, the total yaw angle increases and the flight range decreases sharply. Moreover, a yawing force at an appropriate frequency is able to correct the gun azimuth and elevation perturbation to some extent.

Fabrication,microstructure and mechanical properties of Mg matrix composites reinforced by high volume fraction of sphere TC4 particles

A novel liquid settling method was investigated and applied to fabricate TC4 spherical particle reinforced AZ91 alloy matrix composites.This method was called liquid state settling technique in which TC4 particles would settle down under the force of gravity.High volume fraction(50%)particle reinforced AZ91 composites could be easily obtained via this novel method.This is difficult to achieve for other traditional liquid fabrication methods.In addition,there was a good dispersion of TC4 particles in the AZ91 matrix and no clusters were found,which indicate that this method was feasible.Interfacial reaction occurred and the reaction product was confirmed to be Al2Ti.Three kinds of pre-dispersion technologies were used before the settling process and different interfacial microstructures were found.Theoretical calculation and experimental results both indicated that the interfacial product which was embedded in the matrix strengthened the composites and improved the tensile strength.

Proinflammatory effects and molecular mechanisms of interleukin-17 in intestinal epithelial cell line HT-29

AIM:To evaluate the proinflammatory effects and molecular mechanisms of interleukin(IL)-17 in intestinal epithelial cell line HT-29.METHODS:HT-29 cells were cultured with IL-17,tumor necrosis factor(TNF)-α,or the combination of both IL-17 and TNF-α.Real-time PCR and Western blot were used to measure the gene expression levels of neutrophil chemokines CXCL1,CXCL2,CXCL5,CXCL6,IL-8and TH-17 cell chemokine CCL20,the phosphorylation levels of p38 and TNF-α,and the expression level of IL-8,after using the p38 inhibitor in HT-29 cells.The stable Act1 knockdown HT-29 cell line was established to further test the phosphorylation changes of p38,after using IL-17 and TNF-α.RESULTS:After HT-29 cells were cultured with IL-17and TNF-α,the expression levels of neutrophil chemokines(CXCL1,CXCL2,CXCL5,CXCL6,IL-8)and Th17chemokine(CCL20)significantly improved(24.96±2.53,28.47±2.87,38.08±2.72,33.47±2.41,31.7±2.38,44.37±2.73,respectively),and the differences were all statistically significant(P<0.01).Western blot results showed that IL-17 obviously enhanced the phosphorylation level of p38,which was induced by TNF-α.Compared with the control group,the expression level of IL-8 significantly declined(9.47±1.36 vs 3.06±0.67,P<0.01)when TH-29 cells were cultured with IL-17and TNF-α.p38 inhibition assay showed that the p38pathway played an essential role in the inflammatory response induced by IL-17.p38 phosphorylation levels could not be changed after using IL-17 and TNF-αin the stable Act1 knockdown HT-29 cell line.CONCLUSION:IL-17 significantly promoted the gene expression levels of TNF-α-induced neutrophil chemokines and Th17 cell chemokine.It is obvious that IL-17and TNF-αhave synergistic effects on p38.

Mixed neuroendocrine-nonneuroendocrine neoplasm of the ampulla:Four case reports

BACKGROUND Mixed neuroendocrine-nonneuroendocrine neoplasm(MiNEN)is a rare tumor that occurs in the gastrointestinal tract and pancreas,usually composed of adenocarcinoma and neuroendocrine carcinoma.MiNEN occurring in ampulla is even rarer.We report 4 cases of MiNEN in ampulla,combined with literature review to summarize the clinical features and treatment of the disease,in order to improve the understanding of the disease.CASE SUMMARY A retrospective analysis was performed in 4 cases of MiNEN of the ampulla diagnosed by pathology from 2014 to 2021.The 4 patients were all male,aged 67-81 years(average 72.25 years).Among them,2 patients had jaundice,1 patient had abdominal pain,and 1 patient had jaundice with abdominal pain as the first symptom.All 4 patients underwent enhanced CT or MRI,which all indicated that the tumors were located in the ampulla.Two patients underwent duodenoscopy,and a biopsy revealed ampullary adenocarcinoma.All 4 patients underwent radical pancreaticoduodenectomy.Four cases were followed up:One patient developed severe complications after the operation,his condition deteriorated,and he survived for 1 mo.In the other 3 patients,tumor recurrence was observed during follow-up,and 2 of them survived for 29 mo and 22 mo respectively.One case survived and is still being followed up.CONCLUSION MiNEN of the ampulla are extremely rare,lacking typical clinical symptoms and imaging features,and are usually diagnosed after postoperative histopathological and immunohistochemical examinations.The main treatment is radical surgical resection,which can be combined with chemotherapy.The best method of diagnosis and treatment needs further research.

Ground target localization algorithm for semi-active laser terminalcorrection projectile

A target localization algorithm,which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position,is proposed to obtain the accurate position of ground target in real time in the trajectory correction process of semi-active laser terminal correction projectile.A target localization model is established according to projectile position,attitude and line-of-sight angle.The effects of measurement errors of projectile position,attitude and line-of-sight angle on localization accuracy at different quadrant elevation angles are analyzed through Monte-Carlo simulation.The simulation results show that the measurement error of line-of-sight angle has the largest influence on the localization accuracy.The localization accuracy decreases with the increase in quadrant elevation angle.However,the maximum localization accuracy is less than 7 m.The proposed algorithm meets the accuracy and real-time requirements of target localization.

Successful endoscopic extraction of a proximal esophageal foreign body following accurate localization using endoscopic ultrasound: A case report

BACKGROUND It is rare to find fish bones completely embedded in the wall of the esophagus with endoscopic findings similar to those of submucosal tumors.Most of the patients had the foreign body removed by thoracotomy or thoracoscopy in the past,which resulted in great trauma.CASE SUMMARY We report a 58-year-old woman who experienced dysphagia for 6 d after eating fish.Cervical computed tomography(CT)and endoscopic ultrasonography(EUS)indicated a fish bone completely embedded in the wall of the esophagus with endoscopic findings similar to those of submucosal tumors.The results of CT reconstruction and EUS suggested that the fish bone was parallel to the longitudinal axis of the esophagus.We performed a longitudinal mucosal incision from the highest point of the uplift by using an Olympus dual knife to find the fish bone.Unfortunately,no fish bone was found,so we extended the incision and endoscopic submucosal dissection(ESD)technique was used to detect and remove the fish bone entirety.CONCLUSION The extraction of fish bone via ESD immediately after the injection of methylene blue into the submucous membrane under EUS guidance to obtain accurate localization of the foreign body may be the best treatment for such patients.

Theoretical analysis of the sound absorption characteristics of periodically stiffened micro-perforated plates

The vibro-acoustic responses and sound absorption characteristics of two kinds of periodically stiffened micro-perforated plates are analyzed theoretically. The connected periodical structures of the stiffened plates can be ribs or block-like structures. Based on fundamental acoustic formulas of the micro-perforated plate of Maa and Takahashi, semi-analytical models of the vibrating stiffened plates are developed in this paper. Approaches like the space harmonic method, Fourier transforms and finite element method （FEM） are adopted to investigate both kinds of the stiffened plates. In the present work, the vibro-acoustic responses of micro-perforated stiffened plates in the wavenumber space are expressed as functions of plate displacement amplitudes. After approximate numerical solutions of the amplitudes, the vibration equations and sound absorption coefficients of the two kinds of stiffened plates in the physical space are then derived by employing the Fourier inverse transform. In numerical examples, the effects of some physical parameters, such as the perforation ratio, incident angles and periodical distances etc., on the sound absorption performance are examined. The proposed approaches are also validated by comparing the present results with solutions of Takahashi and previous studies of stiffened plates. Numerical results indicate that the flexural vibration of the plate has a signif- icant effect on the sound absorption coefficient in the water but has little influence in the air.

Lagerindicine, a New Pyrrole Alkaloid Isolated from the Flowers of Lagerstroemia indica Linnaeus

A phytochemical investigation of the EtOH extract of the flowers of Lagerstroemia indica L.led to the isolation and char-acterization of a new pyrrole alkaloid,named lagerindicine(1),along with four known compounds(2-5).Their structures were elucidated by the detailed spectroscopic analysis and comparison with literature data,whereas the structure,in par-ticularly,the absolute configuration(AC)of 1,was firmly determined by total synthesis.All the isolates were evaluated for their cytotoxic effects against human colon cancer cell(HCT-116),and compound 3 exhibited weak cytotoxicity with IC50 value of 28.4μM.

Methodological study on endogenous calcium absorptivity using rats and 41Ca tracing

Elemental calcium plays an important role in human physiology. In order to study the relationship between Ca-intake, Ca-chemical formulation, and Ca-absorptivity, a balance experiment using a ^(41)Ca tracer technique in SD rats was conducted to measure the endogenous fecal calcium and true absorption of calcium. Apparent absorption of calcium was measured as a control to the endogenous calcium labeling experiment. These results show that by using ^(41)Ca labeled endogenous calcium in vivo, researchers could obtain the true calcium absorption data without extrinsic labeling. Therefore, the method was not affected by the chemical structure or type of calcium supplement and might be used in evaluating the absorptivity of marketed calcium supplements.