[A case of diabetic retinopathy with coagulation factor â § and â « deficiency].

The patient was a 48-year-old male with a previous history of diabetes mellitus and hypertension. The patient had persistent bleeding after vitrectomy of the left eye, and the patient was examined for abnormal coagulation factor Ⅷ combined with Ⅻ. This case suggests that we need effective control of blood glucose and blood pressure in patients undergoing vitrectomy in clinical work, and adequate examination of coagulation function. Patients with coagulation factor deficiency should be treated with plasma transfusion to supplement coagulation factors before performing the necessary surgical treatment to prevent severe bleeding.

[Thyroid function of first-trimester twin pregnant women and its association with preterm delivery].

OBJECTIVE: To describe the thyroid function abnormality of first-trimester twin pregnant women according to different references, and to explore its association with preterm delivery. METHODS: Participants, first-trimester twin pregnant women, were recruited at Peking University Third Hospital from March 2017 to February 2020. The thyroid hormone reference for ordinary adults identified on the assay kits by Siemens incorporation, thyroid hormone reference specifically for singleton pregnancy established previously, and thyroid hormone reference specifically for twin pregnancy established previously were used in the description of hypothyroidism and hyperthyroidism for first-trimester twin pregnant women. Thyroid autoantibody reference identified on the assay kits by Siemens incorporation was used in the description of positive thyroid autoantibody. Multivariable log-binomial regression was conducted to examine the association between thyroid function and preterm delivery, in which normal pregnant women according to the three references and normal pregnant women according to twin pregnancy reference accompanied with negative thyroid autoantibody were taken as control respectively. RESULTS: A total of 570 twin pregnant women were finally included. Rates of hypothyroidism according to the three references were 1.2%, 1.6% and 3.5%, respectively. Rates of hyperthyroidism according to the three references were 32.6%, 18.1% and 1.1%, respectively. After adjustment for potential confounding factors, risk of preterm delivery significantly increased in pregnant women with hyperthyroidism according to the twin specific pregnancy reference [adjusted relative risk (ARR)=1.41, 95%CI: 1.14-1.75], while no significant increase was found in those with normal thyroid function according to the twin specific pregnancy reference but hyperthyroidism according to the singleton specific pregnancy reference (ARR=1.00, 95%CI: 0.81-1.25) and in those with hyperthyroidism purely according to the ordinary adult reference (ARR=1.06, 95%CI: 0.85-1.32), compared with those normal according to all the references. Risks of preterm delivery almost significantly or significantly increased in pregnant women with hypothyroidism according to the ordinary adult or singleton specific pregnancy reference (ARR=1.40, 95%CI: 0.88-2.22) and those with hypothyroidism according to the twin specific pregnancy reference (ARR=1.53, 95%CI: 1.03-2.28). Overall analysis of thyroid function according to the twin specific pregnancy reference and thyroid autoantibody showed that risks of preterm delivery almost significantly or significantly increased in pregnant women with simple hypothyroidism (ARR=1.46, 95%CI: 0.93-2.27), simple positive thyroid autoantibody (ARR=1.32, 95%CI: 1.15-1.52), and hypothyroidism accompanied with positive thyroid autoantibody (ARR=1.78, 95%CI: 1.30-2.44), compared with those normal according to the twin specific pregnancy reference with negative thyroid autoantibody. CONCLUSION: The ordinary adult reference and that of singleton pregnancy may lead to under-diagnosis of hypothyroidism and over-diagnosis of hyperthyroidism in first-trimester twin pregnant women. Compared with pregnant women with normal thyroid function, those missed in the diagnosis of hypothyroidism were at a higher risk of preterm delivery, while those over-diagnosed as hyperthyroidism had a similar risk of preterm delivery, indicating a need to develop and generalize twin-pregnancy-specific reference on common indicators of thyroid function. Moreover, the thyroid autoantibody should be taken into consideration in the prenatal diagnosis and treatment to twin pregnant women with hypothyroidism.

Prognostic model for identifying candidates for hepatectomy among patients with hepatocellular carcinoma and hepatic vein invasion.

BACKGROUND: Hepatic vein tumour thrombus (HVTT) is a major determinant of survival outcomes for patients with hepatocellular carcinoma (HCC). An Eastern Hepatobiliary Surgery Hospital (EHBH)-HVTT model was established to predict the prognosis of patients with HCC and HVTT after liver resection, in order to identify optimal candidates for liver resection. METHODS: Patients with HCC and HVTT from 15 hospitals in China were included. The EHBH-HVTT model with contour plot was developed using a non-linear model in the training cohort, and subsequently validated in internal and external cohorts. RESULTS: Of 850 patients who met the inclusion criteria, there were 292 patients who had liver resection and 198 who did not in the training cohort, and 124 and 236 in the internal and external validation cohorts respectively. Contour plots for the EHBH-HVTT model were established to predict overall survival (OS) rates of patients visually, based on tumour diameter, number of tumours and portal vein tumour thrombus. This differentiated patients into low- and high-risk groups with distinct long-term prognoses in the liver resection cohort (median OS 34·7 versus 12·0 months; P < 0·001), internal validation cohort (32·8 versus 10·4 months; P = 0·002) and external validation cohort (15·2 versus 6·5 months; P = 0·006). On subgroup analysis, the model showed the same efficacy in differentiating patients with HVTT in peripheral and major hepatic veins, the inferior vena cava, or in patients with coexisting portal vein tumour thrombus. CONCLUSION: The EHBH-HVTT model was accurate in predicting prognosis in patients with HCC and HVTT after liver resection. It identified optimal candidates for liver resection among patients with HCC and HVTT, including tumour thrombus in the inferior vena cava, or coexisting portal vein tumour thrombus.

ANTECEDENTES: La trombosis tumoral de la vena hepática (hepatic vein tumour thrombus, HVTT) es un determinante importante de los resultados de supervivencia en pacientes con carcinoma hepatocelular (hepatocellular carcinoma, HCC). Se desarrolló el modelo llamado Eastern Hepatobiliary Surgery Hospital (EHBH)-HVTT para predecir el pronóstico de los pacientes con HCC y HVTT después de la resección hepática (liver resection, LR), con el fin de identificar los candidatos óptimos para LR entre estos pacientes. MÉTODOS: Se incluyeron pacientes con HCC y HVTT de 15 hospitales en China. El modelo EHBH-HVTT con gráfico de contorno se desarrolló utilizando un modelo no lineal en la cohorte de entrenamiento, siendo posteriormente validado en cohortes internas y externas. RESULTADOS: De 850 pacientes que cumplieron con los criterios de inclusión, hubo 292 pacientes en el grupo LR y 198 pacientes en el grupo no LR en la cohorte de entrenamiento, y 124 y 236 en las cohortes de validación interna y externa. Los gráficos de contorno del modelo EHBH-HVTT se establecieron para predecir visualmente las tasas de supervivencia global (overall survival, OS) de los pacientes, en función del diámetro del tumor, número de tumores y del trombo tumoral de la vena porta (portal vein tumour thrombus, PVTT). Esto diferenciaba a los pacientes en los grupos de alto y bajo riesgo, con distinto pronóstico a largo plazo en las 3 cohortes (34,7 versus 12,0 meses, 32,8 versus 10,4 meses y 15,2 versus 6,5 meses, P < 0,001). En el análisis de subgrupos, el modelo mostró la misma eficacia en la diferenciación de pacientes con HVTT, con trombo tumoral en la vena cava inferior (inferior vena cava tumour thrombus, IVCTT) o en pacientes con PVTT coexistente. CONCLUSIÓN: El modelo EHBH-HVTT fue preciso para la predicción del pronóstico en pacientes con HCC y HVTT después de la LR. Identificó candidatos óptimos para LR en pacientes con HCC y HVTT, incluyendo IVCTT o PVTT coexistente.

[Course of Revision of the Diagnosis and Treatment Protocol for COVID-19 and the Forensic Contribution].

ABSTRACT: From January 15 to March 3, 2020, seven editions of the guidelines for the diagnosis and treatment of COVID-19 have been issued successively by the National Health Commission of the People's Republic of China, and the guidelines' name was changed from Guidelines for Diagnosis and Treatment of Novel Coronavirus Pneumonia to Diagnosis and Treatment for COVID-19. It optimized and perfected the etiology, clinical manifestations and types, diagnostic procedures and specific treatment measures of the disease, so that the clinical management of the cases was more scientific. In the revision process of guidelines for diagnosis and treatment, forensic medicine experts have also made some positive suggestions on clinical diagnosis and treatment. Especially regarding the pathological changes of COVID-19, they have repeatedly called for rapid autopsy at different levels. With the support, understanding and cooperation of all parties, pathological examination of more than ten cases of the remains were carried out, which made an important contribution to the understanding of the clinical characteristics and pathological characteristics of the disease and the improvement of treatment plans.

[The whole genome-wide screening of the longevity-related gene of Uyghur population in Hotan, Xinjiang].

Objective: To discuss the whole genome-wide screening of the longevity-related gene of Uyghur population in Hotan, Xinjiang. Methods: The whole gene scanning using genome-wide association study (GWAS) based on the pooling DNA and the SNP-Map strategy in the longevity group (≥90 years old) and control group (persons who died before 70 years old) was carried out. Then, through detecting varieties of SNP locus, the frequencies of genotype and allele were calculated by sequencing and PCR- restriction fragment length polymorphism (RFLP) method. Results: There was no significant difference of rs6450874, rs6800573 and rs6741735 genotypes and alleles frequency distributions between the two groups, however, there were statistical differences of rs1718307, rs4449651, rs11217987 and rs2907092 genotypes and alleles frequency distributions between the two groups. The TT genotype of rs11217987 (OR=1.462, P=0.034) and the GG genotype of rs2907092 (OR=3.000, P=0.018) were positively correlated to the longevity. And the T allele of rs11217987 (OR=1.382, 95%CI: 1.075-1.776) and the G allele of rs2907092 (OR=1.672, 95%CI: 1.267-2.205) had strong potential function to prolong life. The TT genotype of rs4449651 (OR=6.892, P=0.009) and rs1718307 (OR=4.036, P<0.001) were positively correlated to the longevity. Moreover, the T allele of both SNPs (OR=1.793, 95%CI: 1.298-2.477; OR=1.830, 95%CI: 1.391-2.407) had strong potential function to prolong life. Conclusions: The GWAS test can effectively and extensively analyze human longevity-related genes. And rs1718307, rs4449651, rs11217987 and rs2907092 are related to the longevity of Uyghur population in Hotan, Xinjiang.

Age-Related Response of Rumen Microbiota to Mineral Salt and Effects of Their Interactions on Enteric Methane Emissions in Cattle.

Mineral salt bricks are often used in cow raising as compensation for mineral losses to improve milk yield, growth, and metabolic activity. Generally, effects of minerals are partially thought to result from improvement of microbial metabolism, but their influence on the rumen microbiota has rarely been documented to date. In this study, we investigated the response of microbiota to mineral salt in heifer and adult cows and evaluated ruminal fermentation and enteric methane emissions of cows fed mineral salts. Twelve lactating Holstein cows and twelve heifers fed a total mixed ration (TMR) diet were randomly allocated into two groups, respectively: a treatment group comprising half of the adults and heifers that were fed mineral salt and a control group containing the other half fed a diet with no mineral salt supplement. Enteric methane emissions were reduced by 9.6% (P < 0.05) in adults ingesting a mineral salt diet, while concentrations of ruminal ammonia, butyrate, and propionate were increased to a significant extent (P < 0.05). Enteric methane emissions were also reduced in heifers ingesting a mineral salt diet, but not to a significant extent (P > 0.05). Moreover, the concentrations of ammonia and volatile fatty acids (VFAs) were not significantly altered in heifers (P > 0.05). Based on these results, we performed high-throughput sequencing to explore the bacterial and archaeal communities of the rumen samples. Succiniclasticum and Prevotella, two propionate-producing bacteria, were predominant in samples of both adults and heifers. At the phylotype level, mineral salt intake led to a significant shift from Succiniclasticum to Prevotella and Prevotellaceae populations in adults. In contrast, reduced abundance of Succiniclasticum and Prevotella phylotypes was observed, with no marked shift in propionate-producing bacteria in heifers. Methanogenic archaea were not significantly abundant between groups, either in adult cows or heifers. The shift of Succiniclasticum to Prevotella and Prevotellaceae in adults suggests a response of microbiota to mineral salt that contributes to higher propionate production, which competes for hydrogen utilized by methanogens. Our data collectively indicate that a mineral salt diet can alter interactions of bacterial taxa that result in enteric methane reduction, and this effect is also influenced in an age-dependent manner.

Cytomixis and meiotic abnormalities during microsporogenesis are responsible for male sterility and chromosome variations in Houttuynia cordata.

Houttuynia cordata (Saururaceae) is a leaf vegetable and a medicinal herb througout much of Asia. Cytomixis and meiotic abnormalities during microsporogenesis were found in two populations of H. cordata with different ploidy levels (2n = 38, 96). Cytomixis occurred in pollen mother cells during meiosis at high frequencies and with variable degrees of chromatin/chromosome transfer. Meiotic abnormalities, such as chromosome laggards, asymmetric segregation and polyads, also prevailed in pollen mother cells at metaphase of the first division and later stages. They were caused by cytomixis and resulted in very low pollen viability and male sterility. Pollen mother cells from the population with 2n = 38 showed only simultaneous cytokinesis, but most pollen mother cells from the population with 2n = 96 showed successive cytokinesis; a minority underwent simultaneous cytokinesis. Cytomixis and irregular meiotic divisions appear to be the origin of the intraspecific polyploidy in this species, which has large variations in chromosome numbers.

In vitro induction of tetraploid garlic with trifluralin.

Garlic (Allium sativum) is propagated asexually. Since sexual cross breeding is almost impossible, means for effective breeding are not currently available and the available production cultivars are seriously aged and degenerated. A possible alternative for breeding is chemical induction. Trifluralin, a type of herbicide, has been reported to provoke chromosome doubling. However, this chemical had not been tested on garlic. We tested various trifluralin concentrations and treatment durations for efficiency in the induction of tetraploid garlic. A clove base of garlic with a stem cv. Gailiang was used as the ex-plant to induce calluses on Murashige and Skoog (MS) medium; the calluses were then inoculated onto MS medium containing different levels of trifluralin and cultured to induce chromosome number variation in vitro. Garlic calluses were effectively induced via the ex-plant and both shoots and roots differentiated well on MS medium containing 6-benzylaminopurine at 3.0 mg/L and indole-3-acetic acid at 0.1 mg/L. However, increases in trifluralin concentration and treatment duration reduced the survival rate and differentiation rate of calluses. Garlic callus cultured for 15 days on medium containing 100 µM trifluralin gave the highest rate of chromosome doubling. Through observation of chromosome number in the root apical cells and the morphology of guard cells on the leaf epidermis of the regenerated plantlets, it was clear that chromosome number variation was induced and tetraploids were produced in vitro by trifluralin treatment.

Diffusivity control in molecule-on-metal systems using electric fields.

The development of methods for controlling the motion and arrangement of molecules adsorbed on a metal surface would provide a powerful tool for the design of molecular electronic devices. Recently, metal phthalocyanines (MPc) have been extensively considered for use in such devices. Here we show that applied electric fields can be used to turn off the diffusivity of iron phthalocyanine (FePc) on Au(111) at fixed temperature, demonstrating a practical and direct method for controlling and potentially patterning FePc layers. Using scanning tunneling microscopy, we show that the diffusivity of FePc on Au(111) is a strong function of temperature and that applied electric fields can be used to retard or enhance molecular diffusion at fixed temperature. Using spin-dependent density-functional calculations, we then explore the origin of this effect, showing that applied fields modify both the molecule-surface binding energies and the molecular diffusion barriers through an interaction with the dipolar Fe-Au adsorption bond. On the basis of these results FePc on Au(111) is a promising candidate system for the development of adaptive molecular device structures.

MicroRNA-130b-5p accelerates the migration and invasion of osteosarcoma via binding to TIMP2.

The article "MicroRNA-130b-5p accelerates the migration and invasion of osteosarcoma via binding to TIMP2, by Z.-H. Cheng, C. Luo, Z.-L. Guo, published in Eur Rev Med Pharmacol Sci 2019; 23 (21): 9267-9276-DOI: 10.26355/eurrev_201911_19419-PMID: 31773678" has been withdrawn from the authors stating that "some data has to be verified by future research". The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/19419.

First isolation of tryptophan from edible lotus (Nelumbo nucifera Gaertn) rhizomes and demonstration of its antioxidant effects.

Various vegetables were investigated for antioxidant activities in two assays, namely, inhibition of lysis of erythrocytes induced by peroxyl radicals and inhibition of lipid peroxidation. The lotus (Nelumbo nucifera Gaertn) rhizome showed the strongest antioxidant activity in both assays. The crude extract (L) of lotus rhizome was chromatographed on a macroporous adsorption resin named NKA. The resulting three fractions were designated L1, L2 and L3, respectively. L2 showed the highest antioxidant activity and was further fractionated by Sephadex LH-20 chromatography. Eight fractions were obtained and named from L2a to L2h, respectively. L2c showed the strongest activity in inhibiting hemolysis of erythrocytes and was further purified by high-performance liquid chromatography. L2c-3 was identified as tryptophan. Its inhibitory concentration of 50% (IC(50)) value in inhibiting hemolysis of erythrocytes was 156.3 microg/ml (i.e. 765.4 microM). This is the first report on isolation of tryptophan from the aqueous extract of lotus rhizome and demonstration of their antioxidant activities.

MicroRNA-130b-5p accelerates the migration and invasion of osteosarcoma via binding to TIMP2.

OBJECTIVE: To elucidate the potential function of microRNA-130b-5p in the progression of osteosarcoma (OS) and the underlying mechanism. MATERIALS AND METHODS: The relative level of microRNA-130b-5p in OS tissues and cell lines was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the microRNA-130b-5p level and the pathological characteristics of OS was analyzed by the Chi-square test. The Kaplan-Meier curves were introduced for assessing the survival of OS patients with high expression and low expression of microRNA-130b-5p. The regulatory effects of microRNA-130b-5p on the migratory and invasive abilities of MG63 and U2OS cells were evaluated by the transwell assay. The relative levels of matrix metalloproteinase 2 (MMP2) and MMP9 in OS cells with overexpression or knockdown of microRNA-130b-5p were determined. The binding relationship between microRNA-130b-5p and TIMP2 was verified through the dual-luciferase reporter gene assay. Finally, a series of rescue experiments were performed to uncover the role of microRNA-130b-5p/TIMP2 in the progression of OS. RESULTS: MicroRNA-130b-5p was upregulated in OS tissues and cell lines. The high expression of microRNA-130b-5p indicated a poor prognosis of OS patients. The overexpression of microRNA-130b-5p accelerated OS cells to migrate and invade. Besides, the relative levels of MMP2 and MMP9 were upregulated in OS cells overexpressing microRNA-130b-5p. TIMP2 was the direct target of microRNA-130b-5p, which was negatively regulated by microRNA-130b-5p. The knockdown of TIMP2 reversed the regulatory effect of microRNA-130b-5p on the migratory and invasive abilities of the OS cells. CONCLUSIONS: MicroRNA-130b-5p is upregulated in OS. It accelerates the progression of OS via inhibiting TIMP2 level.

Optical determination of spin diffusion length and interfacial spin mixing conductance in epitaxial Pd/Fe bilayers.

We present a detailed study of the photoinduced magnetization precession and magnetic relaxation in epitaxial Pd/Fe films on MgO(0 0 1) substrates via all-optical pump-probe techniques. We explicitly formulate the correlation between the Gilbert damping and the effective damping in the optical approach. Furthermore, a non-local Gilbert damping induced by spin pumping is demonstrated self-consistently by the Gilbert damping dependence on Pd thickness and the [Formula: see text] relationship of damping with Fe thickness [Formula: see text]. The non-local Gilbert damping enables the determination of spin diffusion length [Formula: see text] in Pd and interfacial spin mixing conductance [Formula: see text]. Our work paves the way toward the optical determination of spin transport parameters.

24-hour blood pressure in Uygur, Kazakh and Han elderly subjects in China.

The Uygur in Hotan (Xinjiang, China) are reported to have a long life expectancy. The purpose of this study was to clarify the relationship between variations in blood pressure (BP) and longevity. Cross-sectional surveillance was carried out in both Hotan and Barkol. The subjects were divided into five groups: 1. Uygur longevity subjects in Hotan (103 subjects, age >90 yr); 2. Uygur elderly subjects in Hotan (107 subjects, age 65-70 yr); 3. Han elderly subjects in Hotan (41 subjects, age 65-70 yr); 4. Kazakh elderly subjects in Barkol (117 subjects, age 65-70 yr); 5. Han elderly subjects in Barkol (50 subjects, age 65-70 yr). BP was monitored and analyzed using the fourteen devices of ambulatory BP monitoring. The prevalence of hypertension was lowest in the Uygur (16.2% in Uygur elderly subjects in Hotan; 23.7% in Uygur longevity subjects in Hotan; 27.0% in Han elderly subjects in Hotan; 42.0% in Han elderly subjects in Barkol; 50.0% in Kazakh elderly subjects in Barkol). The ratio of dips in BP was largest in the Han (57% in Han elderly subjects in Barkol; 50% in Han elderly subjects in Hotan; 50% in Uygur longevity subjects in Hotan, 49% in Uygur elderly subjects in Hotan; 17% in Kazakh elderly subjects in Barkol). The 24-h mean systolic BP in Uygur longevity subjects in Hotan was not different from those in Uygur elderly subjects and Han elderly subjects in Hotan, nor did the 24-h mean diastolic BP differ from those in Uygur elderly subjects and Han elderly subjects in Hotan respectively. In conclusion, Uygur subjects seem to be less hypertensive, compared to Kazakh subjects. Uygur longevity subjects had more dipping in their BP variation than did the Kazakh subjects in Xinjiang, China.

Syndrome of endemic arsenism and fluorosis. A clinical study.

Sixty-five patients in Xinjiang with syndrome of endemic arsenism and fluorosis (SEAF) were investigated clinically from March 1982 to August 1989. SEAF is a kind of chronic syndrome resulting from the combined, harmful effects of two trace elements, arsenic and fluorine. Peripheral neuritis and cardiovascular changes were observed in this syndrome more often than in simple arsenism or simple fluorosis. The excessive quantities of these two trace elements in blood might have a synergic, harmful effect on the nervous and circulatory systems. No definite conclusion could be reached with regard to the morbidity of skin and visceral tumors in this series. The incidence of associated skin cancer was found to be 7.7% and an associated Grade II squamous cell carcinoma of the esophagus was encountered in one patient.

[Inhibitory effect of tripterine on activities of IL-1, IL-2 and release of PGE2].

Tripterine is one of the components isolated from Tripterygium wilfordii Hook. Previous studies demonstrated that tripterine inhibited not only humoral and cellular immune responses but also some inflammatory responses. The present investigation attempted to observe effect of the drug on productions of IL-1 from macrophages, IL-2 from splenocytes and PGE2 from synovial cells. The results showed that tripterine (0.1-1.0 microgram/ml) significantly inhibited IL-1 activity of murine peritoneal macrophages induced by LPS. Because both intracellular and extracellular IL-1 activities were decreased, so tripterine might be able to reduce the production and release of IL-1. Besides, inhibition of IL-1 production was observed when macrophages were pretreated with the drug for 8 h and 16 h. A good relationship was found between the effect and concentration of tripterine which inhibited IL-2 production from ConA-activated murine splenocytes. Kinetic study indicated that IL-2 production was decreased when splenocytes were pretreated with the drug for 3 h, 6 h and 12 h. Synovial cells obtained from rabbit knee joint were cultured successfully. A23187 was found to augment PGE2 synthesis modestly. Tripterine significantly reduced PGE2 release from synovial cells in a concentration dependent manner.

[Effects of tail suspension on learning and memory function of mice].

Objective. To study the effects of simulated weightlessness on learning and memory capability of the brain. Method. Accuracy fraction, error frequency and pass rate were observed among control, restrained control, tail suspended (TS) control, restrained, and tail suspended mice in square water maze tests. And latent period and error time were observed in control and 30 degrees tail suspension mice in step down test. Result. The indices did not change significantly during learning period. Accuracy fraction of tail suspended group was reduced significantly in the tests as compared with pretest values. In step down test, latent period and error time showed no difference between TS 5 h and 2 d in untrained mice, but shortened evidently after TS 2 d and prolonged after TS 7 d in trained mice, which suggested the degradation of learning and memory ability after TS 5 h and 2 d respectively. Conclusion. Acute tail suspension depressed brain's learning ability and quality, while tail suspension of 7 d and 12 d impaired the spatial memory in mice.

[Analysis of heart rate variability during acute exposure to hypoxia].

Objective. To investigate the changes of autonomic nervous system during acute exposure to an altitude of 5000 m by analysing heart rate variability (HRV). Method. 11 healthy male volunteers aged 18-30 were observed during inhalation of low oxygen gas mixture to simulate acute exposure to hypoxia. HRV was analyzed with both time domain and frequency domain methods. The eleven subjects were divided into two groups--Group A with good tolerance and Group B with poor tolerance. Result. During hypoxia heart rate increased markedly and RMSSD (the square root of the mean squared differences of successive RR intervals) decreased markedly; normalized low-frequency (LFn. u.) and LF/HF ratio increased significantly, while HF and normalized high-frequency (HFn. u.) reduced significantly. LFn. u. and LF/HF increased more apparently in group B than in group A during hypoxia of 5-10 min and RMSSD decreased more in group B during 10-15 min. Conclusion. The results suggested that cardiac sympathetic activity increased and cardiac vagal activity decreased during acute hypoxia. The analysis of HRV could predict the tolerance to hypoxia.

Inhibitors from natural products to HIV-1 reverse transcriptase, protease and integrase.

Acquired immunodeficiency syndrome (AIDS), caused by human immunodeficiency virus type 1 (HIV-1) infection, is still one of the most challenging diseases of the early 21st century. Reverse transcriptase (RT), protease (PR) and integrase (IN) are three key enzymes of HIV-1. Despite the shortcomings of chemical drugs such as toxicity, lack of curative and multiple effects, the search for more and better anti-HIV agents has been focused on natural products. Many natural products have been shown to possess promising activities that could assist in the prevention and amelioration of the disease. Most of these natural anti-HIV agents have other medicinal values as well, which afford them further prospective as novel lead compounds for the development of new drugs. These natural products can deal with both the virus and the various disorders that are caused by HIV. In this review, natural inhibitors of RT, PR and IN have been found to be classified and the relationship between structure and inhibitory activity is discussed.