[Association between sedentary behavior and force expiratory volume in 1 second reduction in middle-aged and elderly adults in communities]

Objective: To analyze the relationship between sedentary behavior and the force expiratory volume in 1 second (FEV₁) reduction in middle-aged and elderly people in communities. Methods: The participants aged ≥40 years were randomly selected from a natural population cohort in Songjiang District, Shanghai, for pulmonary function tests and survey by using international physical activity questionnaire, a generalized additive model was used to analyze the association between sedentary behavior and FEV₁ reduction in the study population and different sex-age subgroups. Results: A total of 3 121 study subjects aged ≥40 years were included. The prevalence of FEV₁ reduction was 14.8%, which was higher in men than in women. There were 24.8% participants were completely sedentary. The prevalence of FEV₁ reduction in women aged <60 years in complete sedentary group was 2.04 (95%CI: 1.11-3.72) times higher than that in non-complete sedentary group. In men aged <60 years, the prevalence of FEV₁ reduction increased with daily sedentary time (OR=1.16, 95%CI: 1.04-1.29), and the prevalence of FEV₁ reduction was also higher in those with sedentary time >5 hours/day than those with sedentary time ≤5 hours/day (OR=3.02, 95%CI: 1.28-7.16). The sensitivity analysis also found such associations. Conclusions: FEV₁ reduction rate in age group <60 years was associated with sedentary behavior. Complete sedentary behavior or absence of moderate to vigorous physical activity played important roles in FEV₁ reduction in women, while men were more likely to be affected by increased sedentary time, which had no association with physical activity. Reducing sedentary time to avoid complete sedentary behavior, along with increased physical activity, should be encouraged in middle-aged and elderly adults in communities to improve their pulmonary function.

[Association between metabolism-related chronic disease combination and prevalence of non-alcoholic fatty liver disease in community residents in Shanghai]

Objective: To explore the combination of metabolism-related chronic diseases associated with the prevalence of non-alcoholic fatty liver disease (NAFLD) in community residents in Shanghai. Methods: The baseline data of Shanghai Suburban Adult Cohort and Biobank were used to understand the prevalence of five metabolism-related chronic diseases, including obesity, hypertension, hyperlipidemia, gout and diabetes, based on questionnaire survey, physical examination and blood biochemical detection. NAFLD was diagnosed by B-ultrasound detection and questionnaire. Multivariable logistic regression model was used to analyze the association of 31 metabolism-related chronic diseases combinations with the prevalence of NAFLD. Results: The median age (Q1, Q3) of 65 477 subjects was 60 (51, 66) years, and men accounted for 40.6%. The overall prevalence of NAFLD was 38.2%, and the prevalence of HAFLD in patients without any of the five metabolism-related chronic diseases was 12.0%. The chronic disease combination with the strongest association with NAFLD was obesity + hypertension + hyperlipidemia + gout + diabetes in the total population (OR=37.94, 95%CI: 31.02-46.41), in women (OR=36.99, 95%CI: 28.78-47.54) and in age group ≥60 years (OR=36.19, 95%CI: 28.25-46.36). The chronic disease combination with the strongest association with NAFLD was obesity + hyperlipidemia + gout + diabetes in men (OR=50.70, 95%CI: 24.62-104.40) and in age group <60 years (OR=49.58, 95%CI: 24.22-101.47). Conclusions: The prevalence of NAFLD in community residents in Shanghai was high. Attention needs to be paid to health of obese people and weight loss should be promoted for them. Community health education should be strengthened for patients complicated with gout, diabetes, hyperlipidemia and hypertension and it is necessary to correct abnormal serum uric acid, blood sugar, blood lipids and blood pressure in a timely manner to reduce the risk of NAFLD.

[Association of hyperuricemia with risk of incident chronic kidney disease in adult in Songjiang district, Shanghai: a follow-up study]

Objective: To evaluate the association of hyperuricemia with the risk for chronic kidney disease (CKD) in community adults. Methods: A community-based follow-up study comprising of 7 276 adults aged 20-74 years who attended the natural population cohort in Eastern China and had no CKD at baseline survey was performed in the Songjiang district, Shanghai. CKD was diagnosed according to the National Kidney Foundation Practice Guidelines for Chronic Kidney Disease criteria. Hyperuricemia was defined as serum uric acid level >420 μmol/L for men and >360 μmol/L for women. Cox proportional hazards model was used to examine the association of hyperuricemia with the risk for CKD. Results: During a median follow-up period of 2.65 year, 301 participants were newly diagnosed with CKD. The cumulative incidence rate and incidence density of CKD were 4.14%, and 16.01/1 000 person-years (95%CI: 14.20-17.82), respectively. A higher prevalence of hyperuricemia was observed in subjects with CKD compared with those without CKD. Multivariate Cox regression model analysis showed that hyperuricemia was associated with the increased risk for CKD, with an adjusted HR of 1.92 (95%CI: 1.46-2.53). Their positive associations remained in almost all the subgroups, including sex, age (<60, ≥60 years), BMI (<25.0, ≥25.0 kg/m²), type 2 diabetes, and hypertension. A significant synergistic effect of the interaction between age and hyperuricemia on CKD was found, and the synergy index was 1.78 (95%CI: 1.18-2.68). Conclusion: The incidence of CKD in adults in Songjiang district was relatively high. Hyperuricemia is an independent risk factor for the development of CKD.

[Study on clinical symptoms and influencing factors of influenza-associated severe acute respiratory illness in children younger than 5 years old in Suzhou of China, 2011-2017]

Objective: To study the influencing factors of influenza-associated severe acute respiratory illness (SARI) in children younger than 5 years of old in Suzhou, and to provide evidence to support the improvement of prevention and control strategies for influenza in children. Methods: We conducted a prospective influenza surveillance for hospitalized SARI and outpatient influenza-like illness (ILI) at Children's Hospital of Soochow University from April 2011 to March 2017. We compared the clinical and other characteristics of influenza-positive patients with SARI to those with ILI to find the differences and to identify influencing factors of influenza-associated SARI, using χ² test and unconditional logistic regression. Results: We found 786 cases of influenza-associated ILI and 413 cases of influenza-associated SARI during the study period. Cough, runny nose, shortness of breath, asthma or wheezing were more common in influenza-associated SARI than in influenza-associated ILI (P<0.01). Univariate and multivariate logistic regression showed that the influencing factors which significantly associated with increased risk of influenza-associated SARI were as follows: younger age (<6 months OR=3.6, 6-23 months aOR=2.5), respiratory infection history within 3 months (aOR=4.5), chronic lung disease history (OR=3.4), fever above 39.0 ℃ (39.0-39.9 ℃ aOR=2.4, ≥40.0 ℃ aOR=6.0), and the presence of A/H1N1 (aOR=2.3), A/H3N2 (aOR=1.9). Conclusion: Children younger than 2 years old, with a history of chronic lung disease, a history of respiratory infection within 3 months, or with a fever peak above 39.0 ℃ should seek medical advice as soon as possible or receive annual influenza vaccination to reduce the incidence of influenza-associated serious outcomes.

[Influence of dietary patterns on type 2 diabetes mellitus in local residents aged 40 years and above in Songjiang district, Shanghai]

Objective: To evaluate the association between dietary pattern and type 2 diabetes mellitus (T2DM) in local residents aged 40 years and above in Songjiang district of Shanghai. Methods: Data was obtained from the baseline investigation of Shanghai Peak-Plan cohort. According to inclusion and exclusion criteria, we selected people with T2DM as the case group, and people without T2DM as controls, matched with gender, age and alcohol intake status. Dietary patterns were established by factor analysis. Conditional logistic regression model (CLRM) was used to explore the relationship between different dietary patterns and T2DM, as well as the association between multiplicative interactions of dietary patterns and T2DM. Results: We used factor analysis to obtain six dietary patterns: including meat, desserts-coarse cereals, condiment-egg, beverage, cereals-tubers and fruit-vegetable. Data from multivariate condition logistic regression suggested that condiment-egg patterns as (OR=0.543, 95%CI: 0.377-0.781), beverage (OR=0.590, 95%CI: 0.409-0.852), cereals-tubers (OR=0.592, 95%CI: 0.414-0.848), fruit-vegetable (OR=0.604, 95%CI: 0.417-0.876) were associated with the reduced risks for T2DM. After analyzing the multiplicative interactions between dietary patterns, there were three interaction items associated with T2DM with statistical significances: the multiplicative interaction between meat pattern and condiments-egg pattern was related with the increased risk for T2MD, and the multiplicative interactions between cereal-tubers pattern, meat pattern between cereal-tubers pattern and fruit-vegetable pattern were related with the reduced risks for T2MD. Conclusions: In the six dietary pattern under study, cereals-tubers pattern undwr studly, fruit-vegetable pattern might be more practical in preventing T2DM. In addition, the dietary pattern with cereals and potatos as the main ingredients, appropriate meat and reduced condiment intake might also play positive roles in reducing the risk for T2DM.

[Hospitalization rates for influenza-associated severe acute respiratory illness in children younger than five years old in Suzhou of China, 2016-2018]

We analyzed the influenza surveillance data of Children's Hospital of Suzhou University from 2016 to 2018 and estimated the hospitalization burden of children under 5 years old due to influenza infection in Suzhou. The results showed that the influenza virus positive rate of 1 451 severe acute respiratory infection (SARI) cases in Children's Hospital of Suzhou University was 13.6% (95%CI: 11.8%-15.3%; 197 cases), among which the influenza pandemic intensity in 2017-2018 was relatively high, and A/H1N1 was the main pandemic virus. It was estimated that the hospitalization rate of influenza-related SARI in children under 5 years old in Suzhou was 6.9‰ (95%CI: 6.6‰-7.2‰), among which the hospitalization rate of children aged<6 months was higher, up to 11.4‰ (95%CI: 9.9‰-12.8‰).

[Epidemiological features of adult chronic kidney diseases in a community-based population in Songjiang district, Shanghai]

Objective: To investigate the prevalence and associated factors of chronic kidney diseases (CKD) in adult residents living in a community of Songjiang district, Shanghai. Methods: A total of 9 257 residents aged 20-75 years old in Xinqiao township of Songjiang district were selected by random cluster sampling. All the participants were interviewed to complete a set of personal questionnaire and undergo physical examinations. Urine and blood tests including markers of kidney damage and related associated factors with CKD, were carried out. Results: Eligible data from 8 207 subjects were enrolled in the study. After adjustment for age and gender, the prevalence of CKD was 8.4% (95%CI: 7.8%-9.0%), with majority of the patients (76.5%) appeared in the early stage (Ⅰ and Ⅱ) of the disease. The prevalence of CKD increased with age and higher prevalence was seen in females than in males (P<0.001). Results from logistic regression analysis showed that factors as: being elderly or female, having hypertension, hyperuricemia, and hyperlipidemia were all independently associated with CKD. Conclusions: The prevalence of CKD appeared relatively high in adult residents of Xinqiao township, Songjiang district where CKD had become a public health problem. Factors as: being female or elderly, hypertension, hyperuricemia, and hyperlipidemia were found to be associated with CKD. Our findings suggested that early prevention and control on CKD to reduce the incidence of end-stage renal diseases and related complications had called for more urgent attention.

[Clinical characteristics and economic burden of influenza among children under 5 years old, in Suzhou, 2011-2017]

Objective: To understand the clinical characteristics and economic burden of influenza-like illness (ILI) children aged 0-59 months in the outpatient settings in Suzhou, China, 2011-2017. Methods: From March 2011 to February 2017, we conducted a prospective surveillance program on ILI for children aged less than 5 years at Soochow University Affiliated Children's Hospital. Through standard questionnaires and follow-up survey via telephone, we collected information regarding the demographic characteristics, medical history, clinical symptoms and both direct and indirect costs associated with influenza, of the patients. We then compared clinical characteristics and economic burden of influenza A/H1N1, A/H3N2, and B infections among children with ILI. Results: We enrolled 6 310 patients with ILI from March 2011 to February 2017 and collected all their throat swabs. 791 (12.9%) of the swabs showed positive for influenza virus, including 88 (11.1%) subtype influenza A/H1N1, 288 (36.4%) subtype influenza A/H3N2, and 415(52.5%) type influenza B. The proportions of cough, rhinorrhea, wheezing, vomiting and convulsion in influenza-positive children were higher than those influenza-negative children. Except for the prevalence rates of cough (χ(2)=9.227, P=0.010), wheezing (χ(2)=7.273, P=0.026) and vomiting (χ(2)=8.163, P=0.017), other clinical symptoms appeared similar between the three viral subtypes. Among all the ILI children, the average total cost per episode of influenza was 688.4 Yuan (95%CI: 630.1-746.7) for influenza-negative children; 768.0 Yuan (95%CI: 686.8-849.3) for influenza-positive children and 738.3 Yuan (95%CI: 655.5-821.1) for influenza B. Children with influenza A/H1N1 spent much more than those with influenza A/H3N2 or influenza B in the total cost (χ(2)=7.237, P=0.028). Conclusion: Children infected influenza showed higher prevalence rates of cough, rhinorrhea, wheezing, vomiting and convulsion than those without influenza. Influenza A/H1N1 subtype caused heavier economic burden than the other two influenza subtypes.

[A 22-year-follow-up cohort study on primary liver cancer in Haimen city of Jiangsu province]

Objective: A prospective cohort study was carried out to assess the mortality and potential risk factors for primary liver cancer (PLC) in Haimen city of Jiangsu province. Methods: The cohort involved 89 789 adult residents aged 25-69 years. Upon the entry of this project, each subject was asked to complete a questionnaire and to provide a blood sample of 10 ml. Surface antigen of hepatitis B virus (HBsAg) was tested by radioimmunoassay. All the subjects were followed-up every year for vital statistics and death certificate information until 2014. Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence interval (95%CI) for PLC mortality associated with HBsAg status and other risk factors. Results: During the 1 299 611 person-years of follow-up, a total of 2 583 PLC cases were identified, including 2 149 men and 434 women. Mortality of the PLC for men and women were 247.80/100 000 person-years and 100.38/100 000 person-years, respectively. Among those who died of PLC, 73.87% had been tested HBsAg positive. HBV infection seemed the predominant risk factor for PLC and the HRs were 15.97 for men (95%CI: 14.29-17.85) and 21.63 for women (95%CI: 16.16-28.96) respectively. Ageing, cigarette smoking, previous history of hepatitis, and family history of HCC were factors associated with the increased risk for PLC. Conclusion: People living in Haimen city had a high risk on PLC. HBV infection appeared the most important risk factor for HCC mortality in this area.

[Cost-effectiveness of multiple screening modalities on breast cancer in Chinese women from Shanghai]

Objective: To determine the most cost-effective modality for breast cancer screening in women living in Shanghai. Methods: A Markov model for breast cancer was redeveloped based on true effect which was derived from a project for detection of women at high risk of breast cancer and an organized breast cancer screening program conducted simultaneously in Minhang district, Shanghai, during 2008 to 2012. Parameters of the model were derived from literatures. General principles related to cost-effectiveness analysis were used to compare the costs and effects of 12 different screening modalities in a simulated cohort involving 100 000 women aged 45 years. Incremental cost-effectiveness ratio (ICER) was used to determine the most cost-effective modality. Sensitivity analysis was conducted to evaluate how these factors affected the estimated cost-effectiveness. Results: The modality of biennial CBE followed by ultrasonic and mammography among those with positive CBE was observed as the most cost-effective one. The costs appeared as 182 526 Yuan RMB per life year gained and 144 386 Yuan RMB per quality adjusted life-year (QALY) saved, which were within the threshold of 2-3 times of local per capita Gross Domestic Product. Results from sensitivity analysis showed that, due to higher incidence rate of breast cancer in Shanghai, the cost per QALY would be 64 836 Yuan RMB lower in Shanghai than the average level in China. Conclusion: Our research findings showed that the biennial CBE program followed by ultrasonic and mammography for those with positive CBE results might serve as the optimal breast cancer screening modality for Chinese women living in Shanghai, and thus be widely promoted in this population elsewhere.

Application values of detection of serum CA199, CA242 and CA50 in the diagnosis of pancreatic cancer

Pancreatic cancer is characterized by rapid onset, high malignancy and high mortality, thus its early diagnosis is effective for improving the survival rate of patients. To discuss the values of detection of carbohydrate antigen (CA) 50, CA242 and CA199 in the diagnosis of pancreatic cancer, this study randomly selected 112 patients who were confirmed as having stage Ia~IIb pancreatic ductal adenocarcinoma (PDAC) in the Shandong Provincial Hospital, China, from May 2012 to May 2013 as a malignant group. One hundred patients with benign pancreatic lesions and 90 healthy people were selected in the same period as a benign group and a healthy control group, respectively. The levels of serum CA199, CA242 and CA50 were detected using electrochemiluminescence. Results demonstrated that the levels of serum CA199, CA242 and CA50 of the malignant group were significantly higher than those of the benign group and the healthy control group (P=0.001; P=0.003; P=0.000). The positive rate of the tumor markers of the malignant group was higher than that of the benign group and the healthy control group, and the differences had statistical significance (P=0.006; P=0.004; P=0.005). In the malignant group, sensitivity of CA199 was the highest (81.42%) as was the specificity of CA242 (80.14%). The detection of two or more markers could improve sensitivity (joint detection based on parallel tests) and specificity (joint detection based on serial tests). Thus the levels of serum tumor markers including CA199, CA242 and CA50 could be used as the assisted indicators for the diagnosis of early-stage PDAC. Joint detection of the three tumor markers is of great significance to improve the diagnostic sensitivity and accuracy of early PDAC.

Structure of A-C Type Intervariant Interface in Nonmodulated Martensite in a Ni-Mn-Ga Alloy

The structure of A-C type intervariant interface in nonmodulated martensite in the Ni54Mn25Ga21 alloy was studied using high resolution transmission electron microscopy. The A-C interface is between the martensitic variants A and C, each of which has a nanoscale substructure of twin-related lamellae. According to their different thicknesses, the nanoscale lamellae in each variant can be classified into major and minor lamellae. It is the boundaries between these lamellae in different variants that constitute the A-C interface, which is thus composed of major-major, minor-minor, and major-minor lamellar boundaries. The volume fraction of the minor lamellae, λ, plays an important role in the structure of A-C interfaces. For major-major and minor-minor lamellar boundaries, they are symmetrical or asymmetrical tilt boundaries; for major-minor boundary, as λ increases, it changes from a symmetrical tilt boundary to two asymmetrical microfacets. Moreover, both lattice and misfit dislocations were observed in the A-C interfaces. On the basis of experimental observations and dislocation theory, we explain how different morphologies of the A-C interface are formed and describe the formation process of the A-C interfaces from λ ≈ 0 to λ ≈ 0.5 in terms of dislocation-boundary interaction, and we infer that low density of interfacial dislocations would lead to high mobility of the A-C interface.

Generalized negative binomial distribution: a promising statistical distribution for Oncomelania hupensis in the lake- and marsh-land regions of China

A new generalization of the negative binomial distribution (GNBD) is introduced and fitted to counts of Oncomelania hupensis, the intermediate host of Schistosoma japonicum, made, in areas of Chinese lakeland and marshland, early in the winter of 2005 and late in the spring of 2006. The GNBD was found to fit the snail data better than the standard negative binomial distribution (NBD) that has previously been widely used to model the distribution of O. hupensis. With two more parameters than the NBD, the GNBD can integrate many discrete distributions and is more flexible than the NBD in modelling O. hupensis. It also provides a better theoretical distribution for the quantitative study of O. hupensis, especially in building an accurate prediction model of snail density. The justification for adopting the GNBD is discussed. The GNBD allows researchers to broaden the field in the quantitative study not only of O. hupensis and schistosomiasis japonica but also of other environment-related helminthiases and family-clustered diseases that have, traditionally, been modelled using the NBD.

[Studies on risk factors for liver fibrosis of schistosomiasis japonica]

OBJECTIVE

To explore the risk factors for schistosomal liver fibrosis.

METHODS

192 hepatitis-negative patients with schistosomiasis were selected and divided into 3 groups according to the result of B ultrasound examination, that is, grade 2 and 3 fibrosis group(81 patients), grade 1 fibrosis group (61 patients) and control group (non-fibrosis, 50 patiets). The univariate and multivariate ordinal regression model was made to analyse the possibly harmful factors influencing the liver damages of these patients.

RESULTS

Four factors were found to be positively associated with schistosomal liver fibrosis. They were: number of treatments of schistosomiasis (OR = 1.75), interval of schistosomal infection(OR = 1.40), history of drinking wine (OR = 1.95) and familial history of advanced schistosomiasis (OR = 2.11).

CONCLUSION

Patients with repeated schistosome infection, long duration of schistosomal infection, long history of drinking and familial history of advanced schistosomiasis had higher risk for liver fibrosis than schistosomiasis patients without these factors.

Antinociceptive and respiratory effects of intrathecal H-Tyr-D-Arg-Phe-Lys-NH2 (DALDA) and [Dmt1] DALDA

DALDA (H-Tyr-D-Arg-Phe-Lys-NH(2)) and [Dmt(1)]DALDA (H-Dmt-D-Arg-Phe-Lys-NH(2)) (Dmt = 2',6'-dimethyltyrosine) are potent and highly selective mu-opioid agonists (K(i)(delta)/K(i)(mu) > 10,000 and K(i)(kappa)/K(i)(mu) > 100). Both peptides carry a 3+ charge at physiological pH. Their antinociceptive and respiratory effects were compared with morphine (MOR) after intrathecal administration in rats. Both DALDA and [Dmt1]DALDA produced dose-dependent and naloxone-reversible antinociceptive effects with relative potencies of 14 and 3000x that of MOR. The antinociceptive potency of [Dmt1]DALDA far exceeded its affinity and potency at the mu-opioid receptor and may be explained by its ability to inhibit norepinephrine (NE) uptake in spinal cord synaptosomes. The antinociceptive response to [Dmt1]DALDA was significantly attenuated by the alpha(2)-adrenergic antagonist yohimbine. Thus, [Dmt1]DALDA may be regarded as a drug with dual actions, and its antinociceptive potency is better described by both its affinity and potency at mu-opioid receptors, and its potency at inhibiting NE uptake. The analgesic duration of an equipotent dose of MOR, DALDA, and [Dmt1]DALDA was 3, 7, and 13 h, respectively, and the long duration may be due to the hydrophilic nature of these peptide analogs. Respiratory effects were determined using whole body plethysmography at 3 and 30x the antinociceptive ED(50). A significant depression in minute ventilation was observed with the higher dose of morphine and both doses of DALDA, but not with either dose of [Dmt1]DALDA. Because of its high antinociceptive potency, long duration of action, and low propensity to induce respiratory depression, [Dmt1]DALDA is of interest as a drug candidate for intrathecal analgesia.

Pharmacokinetics of deguelin, a cancer chemopreventive agent in rats

PURPOSE

To study the pharmacokinetics of deguelin, a naturally occurring potential cancer chemopreventive agent, in rats.

METHODS

[3H]Deguelin was administered intravenously (i.v.) under anesthesia, and blood samples were collected over 24 h. [3H]Deguelin and metabolites were extracted from plasma with ethyl acetate, and quantified by HPLC. Data were analyzed with the WinNolin pharmacokinetic software package to determine pharmacokinetic parameters. A three-compartment first-order elimination model was used to fit the plasma concentration-time curve. In addition, deguelin concentrations in tissues after i.v. and intragastric (i.g.) administration were determined by HPLC, and excretion (feces and urine) was evaluated over a 5-day period after i.g. administration.

RESULTS

Deguelin exhibited a mean residence time (MRT) of 6.98 h and terminal half-life (t1/2(gamma)) of 9.26 h. The area under the curve (AUC) and total clearance (Cl) were 57.3 ng.h/ml and 4.37 l/h per kg, respectively, with an apparent volume of distribution (V) and volume of distribution at steady-state (Vss) of 3.421 l/kg and 30.46 l/kg, respectively. Following i.v. administration, the relative levels of tissue distribution were as follows: heart > fat > mammary gland > colon > liver > kidney > brain > lung. Following i.g. administration, the relative levels of tissue distribution were as follows: perirenal fat > heart > mammary gland > colon > kidney > liver > lung > brain > skin. Within 5 days of i.g. administration, about 58.1% of the [3H]deguelin was eliminated via the feces and 14.4% via the urine. Approximately 1.7% of unchanged deguelin was found in the feces, and 0.4% in the urine.

CONCLUSIONS

An initial pharmacokinetic investigation of deguelin showed that this rotenoid has a relatively long MRT and half-life in plasma in the rat. The compound distributed in the tissues and excreted as metabolites, mainly via the feces.

Pharmacokinetics and tissue distribution of betulinic acid in CD-1 mice

Betulinic acid is a naturally occurring pentacyclic triterpenoid. Betulinic acid has recently been selected by the National Cancer Institute for addition into the RAID (Rapid Access to Intervention in Development) programme. The agent exhibits potential anti-tumour activity and functions in this regard via apoptosis. The objective of the present study was to determine the pharmacokinetics of betulinic acid in CD-1 mice. Serum samples were obtained at designed times after a single 250 or 500 mg/kg intraperitoneal (IP) dose of betulinic acid. Tissue samples (skin, heart, liver, spleen, kidney, lung, brain, colon, caecum, ovary, uterus, thymus, lymph node, bladder, perirenal fat, mammary gland and small intestine) were collected after betulinic acid administration (500 mg/kg). Betulinic acid was extracted with methylene chloride and quantitatively analysed by HPLC/MS. Oleanolic acid and madecassic acid were used as internal standards. Pharmacokinetic parameters were calculated using the WinNonlin pharmacokinetic software package. A two-compartment, first-order model was selected for pharmacokinetic modelling. The results showed that after IP 250 and 500 mg/kg betulinic acid, the serum concentrations reached peaks at 0.15 and 0.23 h, respectively. The 250 and 500 mg/kg above betulinic acid IP doses were found to have elimination half-lives of 11.5 and 11.8 h and total clearances of 13.6 and 13.5 L/kg/h, respectively. The pharmacokinetic parameters observed for IP betulinic acid 500 mg/kg in the skin of mice were as follows: k(a) (h(-1)) 0.257, k(10) (h(-1)) 0.234, t(1/2(alpha)) (h) 2.63, t(1/2(beta)) (h) 20.2, V (L/kg) 0.61, AUC (microg/h/mL) 3504, T(max) (h) 3.90 and C(max) (microg/mL) 300.9. The distribution of betulinic acid in tissues at 24 h post-IP administration in a descending order was as follows: perirenal fat, ovary, spleen, mammary gland, uterus, bladder, lymph node, liver, small intestine, caecum, lung, thymus, colon, kidney, skin, heart and brain.

Effects of ibogaine and noribogaine on the antinociceptive action of mu-, delta- and kappa-opioid receptor agonists in mice

Ibogaine, an alkaloid isolated from the bark of the African shrub, Tabernanthe iboga, has been claimed to decrease the self-administration of drugs of abuse like morphine, cocaine and alcohol. To determine whether these effects are mediated via opioid receptor systems, the effects of ibogaine and its metabolite, noribogaine on the antinociceptive actions of morphine, U-50,488H and [D-Pen2,D-Pen5]enkephalin (DPDPE) which are mu- kappa- and delta-opioid receptor agonists, respectively, were determined in male Swiss-Webster mice. Administration of morphine (7 or 10 mg/kg, s.c.), U-50,488H (15 or 25 mg/kg, i.p.) or DPDPE (10 microg/mouse, i.c.v.) produced antinociception in mice as measured by the tail-flick test. Ibogaine (10, 20 or 40 mg/kg, i.p.) by itself did not alter the tail-flick latency. The same doses of ibogaine injected 10 min before the opioid drugs did not modify the antinociceptive actions of morphine, U-50,488H or DPDPE. Ibogaine administered 4 h or 24 h prior to morphine injection did not modify the antinociceptive action of the latter. A dose of 40 mg/kg (i.p.) of noribogaine enhanced the antinociceptive activity of morphine (10 mg/kg, s.c.). Similarly, the doses of 40 and 80 mg/kg of noribogaine enhanced the antinociception produced by a smaller dose of morphine (5 mg/kg, s.c.). However, antinociception induced by U-50,488H and DPDPE was not modified by noribogaine (10-40 mg/kg). It is concluded that ibogaine, which has been suggested to decrease the self-administration of cocaine and opiates like heroin in humans, does not produce such an action by interacting directly with multiple opioid receptors. However, the metabolite of ibogaine enhances the antinociception of morphine but not of U-50,488H or DPDPE. Thus, in vivo evidence has been provided for the possible interaction of ibogaine with mu-opioid receptor following its metabolism to noribogaine.

Effects of multiple intracerebroventricular injections of [D-Pen2,D-Pen5]enkephalin and [D-Ala2,Glu4]deltorphin II on tolerance to their analgesic action and on brain delta-opioid receptors

Male Swiss-Webster mice were injected intracerebroventricularly (i.c.v.) with [D-Pen2,D-Pen5]enkephalin (DPDPE), a delta 1-opioid receptor agonist (20 micrograms per mouse) twice a day for either 2 or 4 days. Vehicle injected mice served as controls. Treatment of mice with DPDPE for 2 or 4 days decreased its analgesic response by 44 and 76%, respectively in comparison to vehicle injected mice. Treatment of mice with DPDPE for 2 or 4 days decreased density (Bmax) of [3H]DPDPE to bind to brain homogenates by 77 and 76%, respectively, in comparison to vehicle injected controls but the apparent dissociation constant (kd) values were not altered. The effects of i.c.v. injections of [D-Ala2,Glu4]deltorphin II (deltorphin II), a delta 2-opioid receptor agonist (20 micrograms per mouse) twice a day for either 2 or 4 days on its analgesic response as well as on brain receptors for [3H]DPDPE were also determined. The analgesic response to deltorphin II decreased by 51 and 78%, respectively in mice treated with deltorphin II for 2 or 4 days, respectively. Two or four days treatment with deltorphin II decreased the Bmax of [3H]DPDPE by 76 and 87%, respectively. The 2-day treatment also increased the Kd value by 58%, but the 4-day treatment with deltorphin II had no effect on the Kd of [3H]DPDPE to bind to brain membranes. Thus, multiple injections of delta 1- or delta 2-opioid receptor agonists results in the development of tolerance to their analgesic action and the intensity of tolerance increases with the duration of treatment. Both delta 1- and delta 2-opioid receptor agonist, on chronic administration, result in the down-regulation of delta 1-opioid receptors labeled with [3H]DPDPE.

Effects of some 7-arylidene and 7-heteroarylidene morphinan-6-ones on the antinociceptive activity of [D-Pen2, D-Pen5]enkephalin and [D-Ala2, Glu4]deltorphin II and on multiple opioid receptors

The in vivo and functional effects of several 7-arylidene and 7-heteroarylidene morphinan-6-ones were determined at the mu-, delta-, and kappa-opioid receptors using the guinea pig brain membranes, guinea pig ileum (GPI), and mouse vas deferens (MVD). In vivo effects included the antagonism by these compounds given subcutaneously on the antinociceptive actions of intracerebroventricularly injected [D-Pen2, D-Pen5]enkephalin (DPDPE) and [D-Ala2, Glu4]deltorphin II (deltorphin II), the highly selective putative delta 1- and delta 2-opioid receptor agonists. Finally, the partition coefficients of these compounds were estimated (CLOGP) and determined experimentally at pH 7.4 in the 1-octanol/water system. Compared with E-7-benzylidenenaltrexone (BNTX), most compounds except for E-7-(4-chlorobenzylidene)naltrexone, were more potent at delta-opioid receptors than at the mu-opioid receptor, whereas, in comparison to the kappa-opioid receptor, the activities of the E-7-arylidene or E-7-heteroarylidene naltrexone derivatives at the delta-receptor were in the following order, where the 7-substituents were: 4-fluorobenzylidene- > benzylidene > 3-pyridylmethylene- > 4-pyridylmethylene- > 1-methyl-2-imidazolylmethylene > 4-chlorobenzylidene. In the MVD preparation, the potencies at the delta-opioid receptor, in comparison to BNTX, were in the following order, where the 7-substituents were: benzylidene = 1-methyl-2-imidazolylmethylene- > 4-fluorobenzylidene- = 3-pyridylmethylene- = 4-pyridylmethylene-. All compounds antagonized delta 1, and delta 2-opioid receptor agonist-induced analgesia. The antagonist potencies at the delta 1-opioid receptor were in the following order, where the 7-substituents were: benzylidene- > 4-chlorobenzylidene- > 4-fluorobenzylidene- > 3-pyridylmethylene- > 1-methyl-2-imidazolymethylene- approximately 4-pyridylmethylene-, whereas at the delta 2-opioid receptor, the order was benzylidene- > 4-chlorobenzylidene- > 4-fluorobenzylidene- > 3-pyridylmethylene- > 1-methyl-2-imidazolymethylene- > 4-pyridylmethylene. In general, all compounds exhibited greater potency at the delta 2- than delta 1-opioid receptor. The computed partition coefficients were, as expected, greater than the apparent log P values, which were determined experimentally. Generally, the lipophilicity values in decreasing order were: 4-chlorobenzylidene- > 4-fluorobenzylidene- > benzylidene > 3-pyridylmethylene- = 4-pyridylmethylene- > 1-methyl-2-imidazolylmethylene-. In general, the benzylidene and 4-pyridylmethylene derivatives, which have medium lipophilicities, were equally effective at the delta 1- and delta 2-receptors; the 3-pyridylmethylene and 1-methyl-2-imidazolylmethylene derivatives had lower lipophilicities and were more selective for the delta 2- than delta 1-receptor; the 4-chlorobenzylidene and 4-fluorobenzylidene derivatives were more lipophilic and had intermediate activity. The plot of pED50 values for the in vivo tests for the delta 1- and delta 2-receptors showed that the two receptors are not independent with respect to this series of compounds.

Effect of 7-nitroindazole on tolerance to morphine, U-50,488H and [D-Pen2, D-Pen5] enkephalin in mice

The effects of 7-nitroindazole (7-NI), an inhibitor of the neuronal nitric oxide synthase (nNOS) which does not increase blood pressure, on tolerance to the antinociceptive activity of mu-(morphine), kappa-(U-50,488H) and delta-([D-Pen2, D-Pen5]enkephalin, DPDPE) opioid receptor agonists were determined in mice. Male Swiss-Webster mice were made tolerant by twice daily injections of morphine (20 mg/kg, s.c.), U-50,488H (25 mg/kg, i.p.) or DPDPE (20 micrograms/mouse, i.c.v.) for 4 days. When tested on day 5, tolerance to their antinociceptive activity was evidenced by decreased response in chronic drug treated mice in comparison to vehicle-injected mice. Concurrent administration of 7-NI (20, 40 or 80 mg/kg, i.p.) with DPDPE did not modify the development of tolerance to the antinociceptive action of DPDPE. However, 7-NI (40 or 80 mg/kg, i.p.) inhibited the development of tolerance to the antinociceptive activity of morphine and U-50,488H but the lower dose of 7-NI (20 mg/kg, i.p.) was not effective. Chronic administration of 7-NI by itself did not modify the acute response to morphine, U-50,488H or DPDPE. It is concluded that a specific inhibitor of nNOS can inhibit tolerance to the antinociceptive activity of mu- and kappa- but not of delta-opioid receptor agonists in mice.

Effects of competitive and noncompetitive antagonists of the N-methyl-D-aspartate receptor on the analgesic action of delta 1- and delta 2-opioid receptor agonists in mice

1. The effects of MK-801, a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor and LY 235959, a competitive antagonists of the NMDA receptor on the analgesic actions of [D-Pen2,D-Pen5]enkephalin (DPDPE) and [D-Ala2, Glu4] deltorphin II (deltorphin II), the putative delta 1- and delta 2-opioid receptor agonists, respectively, were determined in the male Swiss-Webster mice. 2. Intracerebroventricular administration of DPDPE or deltorphin II produced analgesia. MK-801 administered intraperitoneally 10 min before the injection of DPDPE or deltorphin II, dose-dependently antagonized the analgesic actions of both drugs. 3. LY 235959 also dose-dependently antagonized the analgesic actions of DPDPE and deltorphin II. 4. The effects of MK-801 and LY 235959 on the binding of [3H]-DPDPE to mouse brain membranes were also determined. Neither of the NMDA receptor antagonists had any effect on the binding of [3H]-DPDPE. 5. It is concluded that competitive and noncompetitive antagonists of the NMDA receptor antagonize the analgesic action of delta 1- and delta 2-opioid receptor agonists and that such effects are not mediated via a direct interaction with brain delta-opioid receptors.

Effects of chronic administration of 7-benzylidene-7-dehydronaltrexone and naltriben on the antinociceptive actions of delta 1- and delta 2-opioid receptor agonists

The effects of chronic administration of 7-benzylidene-7-dehydronaltrexone, a delta 1-opioid receptor antagonist and naltriben, a delta 2-opioid receptor antagonist, on the antinociceptive responses to [D-Pen2, D-Pen5] enkephalin and [D-Ala2, Glu4]deltorphin II, delta 1- and delta 2-opioid receptor agonists, respectively, were determined in the mouse. Female B6C3F1 mice were given 7-benzylidene-7-dehydronaltrexone (3 mg/kg/day), naltriben (1 mg/kg/day) or the vehicle by subcutaneously implanted Alzet osmotic minipumps for 7 days. Both [D-Pen2, D-Pen5]enkephalin and [D-Ala2, Glu4]deltorphin II administered intracerebroventricularly (i.c.v.) produced antinociceptive as measured by the tail-flick test with ED50 values of 6.76 and 6.68 micrograms/mouse, respectively. Chronic administration of 7-benzylidene-7-dehydronaltrexone lowered the ED50 of [D-Pen2, D-Pen5]enkephalin but not of [D-Ala2, Glu4]deltorphin II. Chronic administration of naltriben lowered the ED50 of [D-Ala2, Glu4]deltorphin II but had no effect on the ED50 of [D-Pen2, D-Pen5]enkephalin. The binding of [3H][D-Pen2, D-Pen5]enkephalin to whole brain membranes of chronic 7-benzylidene-7-dehydronaltrexone-treated mice did not differ from chronic vehicle-treated mice. On the other hand, chronic administration of naltriben resulted in slight but reproducible elevation in the Bmax value of [3H][D-Pen2, D-Pen5]enkephalin to bind to whole brain membranes in comparison to vehicle-injected controls. The results suggest that chronic treatment with delta 1- and delta 2-opioid receptor antagonist cause behavioral supersensitivity to their agonists, respectively, and provides further evidence for the existence of delta-opioid receptor subtypes.

Effect of nitric oxide synthase inhibition on tolerance to the analgesic action of D-Pen2, D-Pen5 enkephalin and morphine in the mouse

The effects of NG-nitro-L-arginine (NNA), an inhibitor of nitric oxide synthase (NOS) on the development of tolerance to the analgesic action of D-Pen2, D-Pen5 enkephalin (DPDPE), a delta 1 opioid receptor agonist, and morphine were determined in the mouse. Tolerance to DPDPE was induced in male Swiss-Webster mice by twice daily intracerebroventricular (i.c.v.) injections of the drug (20 micrograms/mouse) for 4 days. NNA was injected intraperitoneally (i.p.) 10 min before each injection of DPDPE. Chronic injections of DPDPE resulted in development of tolerance to its analgesic action. Multiple injections of NNA by itself did not modify the analgesic response to DPDPE. Concurrent injections of NNA did not affect the development of tolerance to the analgesic action of DPDPE. Twice daily injections of morphine (15 mg/kg s.c.) for 4 days resulted in the tolerance to its analgesic action. Concurrent administration of NNA with morphine attenuated the development of tolerance to morphine. It is concluded that NOS inhibition attenuates morphine, but not delta, opioid agonist-induced tolerance in the mouse.

Effects of N-methyl-D-aspartate receptor antagonists on the analgesia and tolerance to D-Ala2, Glu4 deltorphin II, a delta 2-opioid receptor agonist in mice

The effects of MK-801, a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor and of LY 235959, a competitive antagonist of the NMDA receptor on the analgesic action and development of tolerance to the analgesic action of D-Ala2, Glu4 deltorphin II (deltorphin II), a delta 2-opioid receptor agonist were determined in mice. Tolerance to deltorphin II was induced in male Swiss-Webster mice by twice daily intracerebroventricular (i.c.v.) injections of the drug (20 micrograms/mouse) for 4 days. To determine the effects of NMDA receptor antagonists, the drugs were injected intraperitoneally in appropriate doses 10 min before each injection of deltorphin II. The doses of MK-801 were 0.01, 0.03 or 0.10 mg/kg whereas those of LY 235959 were 1, 2 or 4 mg/kg. Chronic administration of NMDA receptor antagonists by themselves did not alter the tail-flick latency or the analgesic effect of deltorphin II. MK-801 given concurrently with deltorphin II inhibited the development of tolerance to deltorphin II, the significant effects were observed at 0.03 and 0.10 mg/kg doses. Similar inhibitory effect of development of tolerance to deltorphin II were observed with LY 235959 at 4 mg/kg dose. MK-801 and LY 235959 also antagonized the analgesic action of deltorphin II. It is concluded that antagonism of NMDA receptors attenuates the analgesic action as well as development of tolerance to the analgesic action of delta 2-opioid receptor agonist in the mouse.

Nitric oxide synthase inhibition attenuates tolerance to morphine but not to [D-Ala2, Glu4] deltorphin II, a delta 2-opioid receptor agonist in mice

The effects of NG-nitro-L-arginine (L-NNA) and NG-monomethyl-L-arginine (L-NMMA), two potent inhibitors of nitric oxide synthase (NOS) on the development of tolerance to the analgesic action of [D-Ala2, Glu4] deltorphin II (deltorphin II), a delta 2-opioid receptor agonist, and morphine, a mu-opioid receptor agonist, were determined in mice. Male Swiss-Webster mice were rendered tolerant to deltorphin II by twice daily ICV injections of the drug for 4 days. Tolerance to morphine was induced by twice daily s.c. injections of the drug for 4 days. Multiple injections of deltorphin II (20 micrograms/mouse) or morphine (15 mg/kg) resulted in the development of tolerance to their analgesic action as evidenced by decreases in the response in comparison to mice injected with vehicle. Concurrent administration of L-NNA or L-NMMA (2,4, or 8 mg/kg, i.p.) had no effect on the development of tolerance to the analgesic action of deltorphin II. However, the same doses of L-NNA or L-NMMA inhibited the development of tolerance to the analgesic action of morphine. Acute treatment with L-NNA or L-NMMA did not modify deltorphin II- or morphine-induced analgesia in mice. It is concluded that NOS inhibition attenuates tolerance to the analgesic action of morphine but not to that of deltorphin II, a delta 2-opioid receptor agonist, in the mouse.

Effect of antagonism of the NMDA receptor on tolerance to [D-Pen2,D-Pen5]enkephalin, a delta 1-opioid receptor agonist

The effects of MK-801, a noncompetitive antagonist of the N-methy1-D-aspartate (NMDA) receptor, and of LY 235959, a competitive antagonist of the NMDA receptor, on the development of tolerance to the analgesic action of [D-Pen2,D-Pen5]enkephalin (DPDPE), a delta 1-opioid receptor agonist were determined in mice. Tolerance to DPDPE was induced in male Swiss Webster mice by twice daily ICV injections of the drug (20 micrograms/mouse) for 4 days. To determine the effects of NMDA receptor antagonists, the drugs were injected IP in appropriate doses 10 min before each injection of DPDPE. The doses of MK-801 were 0.01, 0.03, and 0.10 mg/kg whereas those of LY 235959 were 1, 2, and 4 mg/kg. Chronic administration of NMDA receptor antagonists by themselves did not alter the tail flick response or the analgesic effect of DPDPE (10 micrograms/mouse, ICV). MK-801 given concurrently with DPDPE dose-dependently inhibited the development of tolerance to DPDPE, the significant effect being observed at 0.10 mg/kg dose. Similar inhibitory effects on the development of tolerance to DPDPE were observed with LY 235959 at 1, 2, and 4 mg/kg doses. It is concluded that antagonism of NMDA receptors blocks tolerance to the analgesic action of delta 1-opioid receptor agonist in the mouse.

Effects of ohmefentanyl on CA1 field potentials in rat hippocampus slices

The effects of ohmefentanyl (OMF), a new opiate agonist with high affinity and high specificity for mu receptors, was examined on CA1 field potentials in the transverse hippocampal slices. OMF showed two effects upon the evoked population spikes (PS) recorded in stratum pyramidale: 1) a concentration-dependent increase in the amplitude of PS, which was largely reversed by naloxone, and 2) production of a naloxone-reversible additional PS at high stimulus intensities. No significant change was seen in field excitatory postsynaptic potential (EPSP) recorded simultaneously in stratum radiatum. The EC50 for OMF and morphine were 6.6 and 3700 nmol.L-1, respectively. Thus OMF was 560 times more potent than morphine. The mechanism of augmentation by OMF of PS could be attributed to disinhibition as judged from the paired-pulse paradigm.

[Pharmacokinetics of [3H]ohmefentanyl in rats]

Ohmefentanyl (OMF) is a new potent analgesic derived from fentanyl. The pharmacokinetic characteristics of [3H]OMF in rats was studied in this paper. Time courses of concentration of [3H]OMF in plasma after bolus iv could be described as a 3-compartment open kinetic model. The major part of a single dose (1 microgram/kg) of [3H]OMF was rapidly eliminated from plasma by uptake of the active drug by tissues or organs and by biotransformation into hydrophilic metabolites. In respect to its lipophilic nature of OMF the concentrations of [3H]OMF in tissues or organs were much higher than those in plasma. At 1 min after iv, the concentrations of [3H]OMF in the lung, kidney, heart and brain stem were 40, 15, 7.5 and 6 times respectively higher than those in plasma. [3H]OMF and its hydrophilic metabolites were mainly excreted via the kidneys. The urine and feces in 72 h contained about 53% and 15% respectively of the total radioactivity administered. Approximately 65% of [3H]OMF was bound to plasma protein at pH 7.4, 4 degrees C. The bindings were the same for all concentrations of [3H]OMF between 0.02 and 1 ng/ml plasma in vitro.