Commercial compost amendments inhibit the bioavailability and plant uptake of per- and polyfluoroalkyl substances in soil-porewater-lettuce systems.

Compost is widely used in agriculture as fertilizer while providing a practical option for solid municipal waste disposal. However, compost may also contain per- and polyfluoroalkyl substances (PFAS), potentially impacting soils and leading to PFAS entry into food chains and ultimately human exposure risks via dietary intake. This study examined how compost affects the bioavailability and uptake of eight PFAS (two ethers, three fluorotelomer sulfonates, and three perfluorosulfonates) by lettuce (Lactuca sativa) grown in commercial organic compost-amended, PFAS spiked soils. After 50 days of greenhouse experiment, PFAS uptake by lettuce decreased (by up to 90.5 %) with the increasing compost amendment ratios (0-20 %, w/w), consistent with their decreased porewater concentrations (by 30.7-86.3 %) in compost-amended soils. Decreased bioavailability of PFAS was evidenced by the increased in-situ soil-porewater distribution coefficients (Kd) (by factors of 1.5-7.0) with increasing compost additions. Significant negative (or positive) correlations (R2 ≥ 0.55) were observed between plant bioaccumulation (or Kd) and soil organic carbon content, suggesting that compost amendment inhibited plant uptake of PFAS mainly by increasing soil organic carbon and enhancing PFAS sorption. However, short-chain PFAS alternatives (e.g., perfluoro-2-methoxyacetic acid (PFMOAA)) were effectively translocated to shoots with translocation factors > 2.9, increasing their risks of contamination in leafy vegetables. Our findings underscore the necessity for comprehensive risk assessment of compost-borne PFAS when using commercial compost products in agricultural lands.

Enhanced indigenous consortia for the remediation of uranium-contaminated groundwater by bioaugmentation: Reducing and phosphate-solubilizing consortia.

To investigate the strengthening effects and mechanisms of bioaugmentation on the microbial remediation of uranium-contaminated groundwater via bioreduction coupled to biomineralization, two exogenous microbial consortia with reducing and phosphate-solubilizing functions were screened and added to uranium-contaminated groundwater as the experimental groups (group B, reducing consortium added; group C, phosphate-solubilizing consortium added). ß-glycerophosphate (GP) was selected to stimulate the microbial community as the sole electron donor and phosphorus source. The results showed that bioaugmentation accelerated the consumption of GP and the proliferation of key functional microbes in groups B and C. In group B, Dysgonomonas, Clostridium_sensu_stricto_11 and Clostridium_sensu_stricto_13 were the main reducing bacteria, and Paenibacillus was the main phosphate-solubilizing bacteria. In group C, the microorganisms that solubilized phosphate were mainly unclassified_f_Enterobacteriaceae. Additionally, bioaugmentation promoted the formation of unattached precipitates and alleviated the inhibitory effect of cell surface precipitation on microbial metabolism. As a result, the formation rate of U-phosphate precipitates and the removal rates of aqueous U(VI) in both groups B and C were elevated significantly after bioaugmentation. The U(VI) removal rate was poor in the control group (group A, with only an indigenous consortium). Propionispora, Sporomusa and Clostridium_sensu_stricto_11 may have played an important role in the removal of uranium in group A. Furthermore, the addition of a reducing consortium promoted the reduction of U(VI) to U(IV), and immobilized uranium existed in the form of U(IV)-phosphate and U(VI)-phosphate precipitates in group B. In contrast, U was present mainly as U(VI)-phosphate precipitates in groups A and C. Overall, bioaugmentation with an exogenous consortium resulted in the rapid removal of uranium from groundwater and the formation of U-phosphate minerals and served as an effective strategy for improving the treatment of uranium-contaminated groundwater in situ.

Multi-media interaction improves the efficiency and stability of the bioretention system for stormwater runoff treatment.

Bioretention systems are one of the most widely used stormwater control measures for urban runoff treatment. However, stable and effective dissolved nutrient treatment by bioretention systems is often challenged by complicated stormwater conditions. In this study, pyrite-only (PO), pyrite-biochar (PB), pyrite-woodchip (PW), and pyrite-woodchip-biochar mixed (M) bioretention systems were established to study the feasibility of improving both stability and efficiency in bioretention system via multi-media interaction. PB, PW, and M all showed enhanced dissolved nitrogen and/or phosphorus removal compared to PO, with M demonstrating the highest efficiency and stability under different antecedent drying durations (ADD), pollutant levels, and prolonged precipitation depth. The total dissolved nitrogen and dissolved phosphorus removal in M ranged between 64%-86% and 80%-95%, respectively, with limited organic matter and iron leaching. Pore water, microbial community, and material analysis collectively indicate that pyrite, woodchip, and biochar synergistically facilitated multiple nutrient treatment processes and protected each other against by-product leaching. Pyrite-woodchip interaction greatly increased nitrate removal by facilitating mixotrophic denitrification, while biochar further enhanced ammonium adsorption and expanded the denitrification area. The Fe3+ generated by pyrite aerobic oxidation was adsorbed on the biochar surface and potentially formed a Fe-biochar composite layer, which not only reduced Fe3+-induced pyrite excessive oxidation but also potentially increased organic matter adsorption. Fe (oxyhydr)oxides intermediate product formed by pyrite oxidation, in return, controlled the phosphorus and organic matter leaching from biochar and woodchip. Overall, this study demonstrates that multi-media interaction may enable bioretention systems to achieve stable and effective urban runoff treatment.

Clinical evidence of three traditional Chinese medicine drugs and three herbal formulas for COVID-19: A systematic review and meta-analysis of the Chinese population.

BACKGROUND: The coronavirus disease 2019 (COVID-19) continues to spread worldwide. Integrated Chinese and Western medicine have had some successes in treating COVID-19. OBJECTIVE: This study aims to evaluate the efficacy and safety of three traditional Chinese medicine drugs and three herbal formulas (3-drugs-3-formulas) in patients with COVID-19. SEARCH STRATEGY: Relevant studies were identified from 12 electronic databases searched from their establishment to April 7, 2022. INCLUSION CRITERIA: Randomized controlled trials (RCTs), non-RCTs and cohort studies that evaluated the effects of 3-drugs-3-formulas for COVID-19. The treatment group was treated with one of the 3-drugs-3-formulas plus conventional treatment. The control group was treated with conventional treatment. DATA EXTRACTION AND ANALYSIS: Two evaluators screened and selected literature independently, then extracted basic information and assessed risk of bias. The treatment outcome measures were duration of main symptoms, hospitalization time, aggravation rate and mortality. RevMan 5.4 was used to analyze the pooled results reported as mean difference (MD) with 95% confidence interval (CI) for continuous data and risk ratio (RR) with 95% CI for dichotomous data. RESULTS: Forty-one studies with a total of 13,260 participants were identified. Our analysis suggests that compared with conventional treatment, the combination of 3-drugs-3-formulas might shorten duration of fever (MD = -1.39; 95% CI: -2.19 to -0.59; P < 0.05), cough (MD = -1.57; 95% CI: -2.16 to -0.98; P < 0.05) and fatigue (MD = -1.36; 95% CI: -2.21 to -0.51; P < 0.05), decrease length of hospital stay (MD = -2.62; 95% CI -3.52 to -1.72; P < 0.05), the time for nucleic acid conversion (MD = -2.92; 95% CI: -4.26 to -1.59; P < 0.05), aggravation rate (RR = 0.49; 95% CI: 0.38 to 0.64; P < 0.05) and mortality (RR = 0.34; 95% CI: 0.19 to 0.62; P < 0.05), and increase the recovery rate of chest computerized tomography manifestations (RR = 1.22; 95% CI: 1.14 to 1.3; P < 0.05) and total effectiveness (RR = 1.24; 95% CI: 1.09 to 1.42; P < 0.05). CONCLUSION: The 3-drugs-3-formulas can play an active role in treating all stages of COVID-19. No severe adverse events related to 3-drugs-3-formulas were observed. Hence, 3-drugs-3-formulas combined with conventional therapies have effective therapeutic value for COVID-19 patients. Further long-term high-quality studies are essential to demonstrate the clinical benefits of each formula. Please cite this article as: You LZ, Dai QQ, Zhong XY, Yu DD, Cui HR, Kong YF, Zhao MZ, Zhang XY, Xu QQ, Guan ZY, Wei XX, Zhang XC, Han SJ, Liu WJ, Chen Z, Zhang XY, Zhao C, Jin YH, Shang HC. Clinical evidence of three traditional Chinese medicine drugs and three herbal formulas for COVID-19: A systematic review and meta-analysis of the Chinese population. J Integr Med. 2023; 21(5): 441-454.

Research progress of oral allergy syndrome / 中华预防医学杂志

Oral allergy syndrome (OAS) is an IgE-mediated hypersensitivity. Patients with pollen allergy will experience oropharyngeal allergy after eating fresh fruits or vegetables containing homologous pathogenesis-related allergen, occasionally accompanied by systemic symptoms, it is a special type of food hypersensitivity in which respiratory allergens and food allergens are similar structurally and lead to the cross-reactivity. At present, there is little research and attention to it in China. To master the definition, epidemiological characteristics, pathological mechanism, diagnosis, prevention and treatment of OAS is very important to the prevention and control of OAS. This article reviews the research progress of OAS, providing reference and prevention basis for clinicians to improve the diagnosis and differential diagnosis of OAS.

Cortical Organoid-on-a-Chip with Physiological Hypoxia for Investigating Tanshinone IIA-Induced Neural Differentiation.

Cortical organoids represent cutting-edge models for mimic human brain development during the early and even middle stage of pregnancy, while they often fail to recreate the complex microenvironmental factors, such as physiological hypoxia. Herein, to recapitulate fetal brain development, we propose a novel cortical organoid-on-a-chip with physiological hypoxia and further explore the effects of tanshinone IIA (Tan IIA) in neural differentiation. The microfluidic chip was designed with a micropillar array for the controlled and efficient generation of cortical organoids. With low oxygen, the generated cortical organoids could recapitulate key aspects of early-gestational human brain development. Compared to organoids in normoxic culturing condition, the promoted neurogenesis, synaptogenesis and neuronal maturation were observed in the present microsystem, suggesting the significance of physiological hypoxia in cortical development. Based on this model, we have found that Chinese herbal drug Tan IIA could promote neural differentiation and maturation, indicating its potential therapeutic effects on neurodevelopmental disorders as well as congenital neuropsychiatric diseases. These results indicate that the proposed biomimetic cortical organoid-on-a-chip model with physiological hypoxia can offer a promising platform to simulate prenatal environment, explore brain development, and screen natural neuroactive components.

[Concept and method of evidence-based toxicology of traditional Chinese medicine from origin and development of evidence-based toxicology].

Advances in science and technology promote the rapid development of toxicological detection technologies. However, there is still a lack of decision-making tools for toxicological risk assessment, such as the lack of transparent schemes to evaluate current toxicological research and practice and the lag of toxicological testing tools to evaluate toxicity, resulting in difficulties in toxicity verification and hindering the transformation of toxicological research paradigm. Some scholars have proposed to integrate the concept of evidence-based medicine with the toxicological practice to improve the technical methods of toxicological research concept and risk assessment decision-making. With the promotion of relevant scholars and academic organizations, the concept and connotation of evidence-based toxicology have gradually become clear and a framework for research and practice has been initially formed. Although there are still many challenges, it also provides a new idea for the toxicity risk assessment and safe medication decision-making of traditional Chinese medicine(TCM). The era of digital intelligence has brought new opportunities and broad space for the development of TCM evidence-based toxicology. The exploration of TCM evidence-based toxicology from concept to method is an important embodiment of the development of TCM evidence-based toxicology, and will also promote the continuous enrichment and improvement of the research and practice system of TCM evidence-based toxicology.

Anti-hypertensive and endothelia protective effects of Fufang Qima capsule on primary hypertension via adiponectin/adenosine monophosphate activated protein kinase pathway.

OBJECTIVE: To investigate the potential mechanism of the vascular remodeling effect and provide additional information about anti-hypertension activity of Fufang Qima capsule. METHODS: Spontaneous hypertensive rats (SHRs) were used to study the underlying mechanism of the anti-hypertension activity of QM. In this study, SHRs were randomly divided into 5 groups: model group, Telmisartan group (7.2 mg/kg, p.o.), and three QM groups (0.9298, 1.8596, and 3.7192 g/kg, p.o.). Wistar Kyoto rats (WKY) were used as normal control group. Blood pressure (BP), aorta, perivascular adipose tissue (PVAT) histology were investigated to evaluate the effect of QM. Nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) phosphorylation were measured. Adiponectin (APN) secretion, as well as APN signal pathway proteins including APN, adiponectin receptors (R1 and R2) and adenosine 5'-monophosphate-activated protein kinase (AMPK) were all analyzed. RESULTS: QM significantly reduced BP and ameliorated the vascular pathological change, i.e. intima media thicken and collagen fiber hyperplasia. Meanwhile, QM increased concentration of NO and the phosphorylation of eNOS in the aorta. The anti-hypertensive and endothelia-protective effect of QM could be attributed to activating APN/ AMPK pathway by up-regulating the expression of APN in PVAT and APN Receptor 2, AMPKα and phosphorylated AMPKα in the aorta. CONCLUSION: The QM alleviation effect mechanism for primary hypertension was via modulating the APN/AMPK signal pathway.

Influence of natural organic matter and pH on phosphate removal by and filterable lanthanum release from lanthanum-modified bentonite.

Lanthanum modified bentonite (LMB) has been applied to eutrophic lakes to reduce phosphorus (P) concentrations in the water column and mitigate P release from sediments. Previous experiments suggest that natural organic matter (NOM) can interfere with phosphate (PO4)-binding to LMB and exacerbate lanthanum (La)-release from bentonite. This evidence served as motivation for this study to systematically determine the effects of NOM, solution pH, and bentonite as a La carrier on P removal. We conducted both geochemical modeling and controlled-laboratory batch kinetic experiments to understand the pH-dependent impacts of humic and fulvic acids on PO4-binding to LMB and La release from LMB. The role of bentonite was studied by comparing PO4 removal obtained by LMB and La3+ (added as LaCl3 salt to represent the La-containing component of LMB). Our results from both geochemical modeling and batch experiments indicate that the PO4-binding ability of LMB is decreased in the presence of NOM, and the decrease is more pronounced at pH 8.5 than at 6. At the highest evaluated NOM concentration (28 mg C L-1), PO4-removal by La3+ was substantially lower than that by LMB, implying that bentonite clay in LMB shielded La from interactions with NOM, while still allowing PO4 capture by La. Finally, the presence of NOM promoted La-release from LMB, and the amount of La released depended on solution pH and both the type (i.e., fulvic/humic acid ratio) and concentration of NOM. Overall, these results provide an important basis for management of P in lakes and eutrophication control that relies on LMB applications.

Evaluation of the protective effect of lycopene on growth performance, intestinal morphology, and digestive enzyme activities of aflatoxinB1 challenged broilers.

The current study was conducted to investigate the protective efficiency of dietary lycopene (LYC) supplementation on growth performance, intestinal morphology, and digestive enzyme activities aflatoxinB1 (AFB1 ) challenged broilers. A total of 240 days old Arber across male broiler chicks were randomly allocated in five treatments and six replicates (eight birds per replicate); feed and water were provided ad libitum during the 42 days experiment. The treatment diets were as follows: (i) Basal diet (control), (ii) Basal diet + 100 µg/kg AFB1 contaminated diet, (iii) Basal diet + 100 µg/kg AFB1  + 100 mg/kg LYC1, (iv) Basal diet + 100 µg/kg AFB1  + 200 mg/kg LYC2, and (v) Basal diet + 100 µg/kg AFB1  + 400 mg/kg LYC3. The results showed that the addition of LYC to AFB1 contaminated broiler diets significantly increased (p < .05) average daily gain (ADG) and decreased feed conversion ratio (FCR) compared to the AFB1 diet. AFB1 diet decreased the intestinal villus height (VH) and crypt depth ratio (VCR) while increasing the crypt depth (CD). However, dietary LYC supplemented diets relieved the intestinal morphological alterations. Dietary LYC supplementation (200 and 400 mg/kg) significantly improved (p < .05) intestinal digestive enzyme amylase and lipase activities with AFB1 contaminated diet. These findings suggested that LYC is a promising feed supplement in the broiler industry, alleviating the harmful effects of AFB1 .

Human coronaviruses and therapeutic drug discovery.

BACKGROUND: Coronaviruses (CoVs) are distributed worldwide and have various susceptible hosts; CoVs infecting humans are called human coronaviruses (HCoVs). Although HCoV-specific drugs are still lacking, many potent targets for drug discovery are being explored, and many vigorously designed clinical trials are being carried out in an orderly manner. The aim of this review was to gain a comprehensive understanding of the current status of drug development against HCoVs, particularly severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). MAIN TEXT: A scoping review was conducted by electronically searching research studies, reviews, and clinical trials in PubMed and the CNKI. Studies on HCoVs and therapeutic drug discovery published between January 2000 and October 2020 and in English or Chinese were included, and the information was summarized. Of the 3248 studies identified, 159 publication were finally included. Advances in drug development against HCoV, especially SARS-CoV-2, are summarized under three categories: antiviral drugs aimed at inhibiting the HCoV proliferation process, drugs acting on the host's immune system, and drugs derived from plants with potent activity. Furthermore, clinical trials of drugs targeting SARS-CoV-2 are summarized. CONCLUSIONS: During the spread of COVID-19 outbreak, great efforts have been made in therapeutic drug discovery against the virus, although the pharmacological effects and adverse reactions of some drugs under study are still unclear. However, well-designed high-quality studies are needed to further study the effectiveness and safety of these potential drugs so as to provide valid recommendations for better control of the COVID-19 pandemic.

Study of hot spring bathing and chronic disease prevalence among residents between 30 and 65 in typical hot spring areas of Guizhou Province / 上海预防医学

Objective To investigate hot spring bathing behavior and chronic disease prevalence of residents aged 30 to 65 in typical hot spring areas of Guizhou Province. Methods Totally 3 708 individuals between 30 and 65 in five typical hot spring areas of Guizhou Province were included in this study. Their hot spring bathing behavior and chronic disease prevalence were recorded. Unconditional logistic regression was used to analyze the association between hot spring bathing and the incidence of chronic diseases. Results 71.3% of the residents in the hot spring areas had bathed in hot springs, with the proportion higher in males than females(χ2=92.856, P < 0.001). 76.3% of people took hot spring baths fewer than or equal to 6 times per year, 30.8% of residents often chose to take hot spring baths in the evening, and 37.6% of the residents took hot spring baths for 21-40 minutes. Bathing was more common in winter. 11.5% and 17.9% of the residents added other substances and used hot spring facilities, and most of them added traditional Chinese medicine and used the sauna. 46.6% and 41.6 % of the residents took hot spring baths to relax and relieve fatigue. The self-reported prevalence rate of chronic diseases was 522.1‰, and the top five single diseases were lumbar intervertebral disc disease(119.7‰), hypertension(118.1‰), urinary calculus(77.7‰), cervical intervertebral disc disease(53.7‰)and osteogenesis(44.5‰). Compared with those who never bathed in hot springs, taking hot spring baths 7-11 times a year was negatively correlated with chronic diseases.(OR=0.551, 95%CI: 0.345-0.879). Conclusion Hot spring bathing is popular in typical hot spring areas of Guizhou Province, but its frequency is not high. The overall prevalence of chronic diseases is relatively high, and the order of most prevalent chronic diseases is different from that in other areas. Proper hot spring bathing is negatively correlated with chronic diseases.

Current status and influencing factors of osteoporosis risk among residents in typical hot spring areas in Guizhou Province / 上海预防医学

Objective To understand the current status of osteoporosis risk and influencing factors for residents from 30 to 65 years old in typical hot spring areas in Guizhou province, and to provide a theoretical basis for reducing the risk of osteoporosis and the prevention of osteoporosis in the population. Methods A health questionnaire for residents in typical hot spring areas in Guizhou, osteoporosis risk test questions, Pittsburgh sleep quality index(PSQI), etc were used. A face-to-face survey of 3 708 residents was conducted, and logistic regression was used to analyze the influencing factors of osteoporosis risk in hot spring areas. Results 2 403(64.81%)residents of 3 708 people surveyed were at risk of osteoporosis, of whom 1 434(87.4%)males and 969 females(47.1%)had a higher risk of osteoporosis (χ2=652.4, P < 0.001). As age increased, more residents were at risk of osteoporosis(χ2=273.4, P < 0.001), and numbers of residents of 30-39 years old, 40-59 years old, and above 60 years of age at risk of osteoporosis were 319(49.2%), 1 572(62.9%), and 512(93.6%). Male osteoporosis risk was negatively correlated with an education level of undergraduate and above(OR=0.37, 95%CI: 0.19-0.73). Age 40-59(OR=1.54, 95%CI: 1.07-2.22), 60 and above(OR=6.39, 95%CI: 2.76-14.79), and sleep disorders(OR=1.59, 95%CI: 1.08-2.35)may increase the risk of osteoporosis in male residents in hot spring areas. Less oil in daily diet may increase the risk of osteoporosis in women(OR=1.70, 95%CI: 1.23-2.36). Age 40-59(OR=1.54, 95%CI: 1.17-2.03), over 60 and above(OR=16.24, 95%CI: 10.10-26.12), and sleep disorders(OR=1.84, 95%CI: 1.48-2.28)were positively correlated with risk of osteoporosis in women. Women with junior high school degree(OR=0.61, 95%CI: 0.47-0.80), high school degree(OR=0.57, 95%CI: 0.37-0.89)and undergraduate degree and above(OR=0.59, 95%CI: 0.39-0.98)had a lower risk of osteoporosis than women who were illiterate or semi-illiterate. The osteoporosis risk test questions showed that smoking, heavy drinking, and erectile dysfunction and reduced sexual desire were the main sources of osteoporosis risk in men. Menopause before the age of 60, ≤45 years old, no milk and no calcium supplements, parents with osteoporosis or bone fractures were the major risk sources of osteoporosis in women. Conclusion The risk of osteoporosis among male residents from 30 to 65 years old in typical hot spring areas in Guizhou province is higher than that among women. Education of osteoporosis prevention should be strengthened among local residents to promote healthy behaviors and lifestyles.

Radial Pulse Wave Signals Combined with Ba-PWV for the Risk Prediction of Hypertension and the Monitoring of Its Accompanying Metabolic Risk Factors.

Our aim was to study whether radial pulse wave signals can improve the risk prediction of incident hypertension and are associated with its concomitant metabolic risk factors beyond the traditional cardiovascular risk factor Ba-PWV. By enrolling 523 Chinese subjects in this study, linear and stepwise regression analysis was performed to assess the association of radial artery pulse wave signals and Ba-PWV with blood pressure and its related metabolic risk factors such as fasting plasma glucose (FPG), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and uric acid (UA). The area under the receiver-operating characteristic curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated by risk assessment plot to compare the discriminative ability among models with and without radial artery pulse wave signals. After adjusting related confounding factors, radial artery pulse wave variable h 3/h 1 was selected as the sensitive influential factor for blood pressure. Moreover, a new model with h 3/h 1 had a higher AUC than the reference model without it (0.86 vs 0.84; P=0.030). And the NRI and IDI for the new model was 50.0% (P=0.017) and 3.16% (P=0.044), respectively. In addition to Ba-PWV, we found that the decrease of t 4, t 5, and h 5 might be associated with higher FPG, TC, LDL-C, and UA and lower HDL-C. This research might provide a valuable additional tool for remote wearable monitoring of radial artery pulse wave signals in hypertension risk evaluation and management.

Efficacy of combined treatment with albendazole and baicalein against eosinophilic meningitis induced by Angiostrongylus cantonensis in mice.

Angiostrongylus cantonensis infection causes eosinophilic meningitis in humans. Baicalein is a flavonoid originally isolated from the roots of Scutellaria baicalensis Georgi. In this study we evaluated the efficacy of the combination of albendazole and baicalein for treating eosinophilic meningitis in BALB/c mice. Therapeutic efficacy included the survival time, body weight, neurological function, leucocyte and eosinophil counts, eotaxin concentration, matrix metalloproteinase-9 (MMP-9) activity, larval recovery and histopathological examination. The results showed that the combination of albendazole and baicalein was more effective than either drug administered singly. Combination therapy increased the survival time, decreased body weight loss, neurological dysfunction, leucocyte response, eotaxin concentration and MMP-9 activity. Our results suggest that the combination of albendazole and baicalein may exhibit synergistic beneficial effects in the treatment of eosinophilic meningitis induced by A. cantonensis.

[Studies on the chemical comstituents of Pithecellobium clypearia].

OBJECTIVE: To study the chemical constituents of Pithecellobium clypearia. METHODS: The compounds were isolated from Pithecellobium clypearia with column chromatography. Their structures were characterized on the basis of their physical and chemical preperties, as well as chromatographic and spectroscopic evidences. RESULTS: A pair of isomeric flavans consisting of 7, 3'-O-di-gallyoltricetiflavan (I) and 7,4'-O-di-gallyoltricetiflavan (II), along with a catechin compound (-)-epigallocatechin-7-O-gallate (III) were isolated from the leaves and twigs of Pithecellobium clypearia. CONCLUSION: Compound I is a new flavan. Compound III is isolated from Pithecellobium genus for the first time, and its 13C-NMR data is firstly given in the present study.

Expression profile, localization of an 8-kDa calcium-binding protein from Schistosoma japonicum (SjCa8), and vaccine potential of recombinant SjCa8 (rSjCa8) against infections in mice.

Researches on genes expressed in a cercarial stage-specific manner may help us understand the molecular events and functions during schistosome invasion of skin. A genomic clone encoding 8-kDa calcium-binding protein (SjCa8) specifically expressed in cercariae and skin-stage schistosomulum (transformed within 3 h) was obtained from cercariae. Recombinant protein was expressed in vector pET32a (+) and purified using a Ni-NTA purification system. The target protein SjCa8 was determined by matrix-assisted laser desorption/ionization time-of-flight (TOF)/TOF mass spectrometer after thrombin digestion and dialysis. Reverse transcriptase polymerase chain reaction and Western blot revealed SjCa8 can be detected in cercaria and skin-stage schistosomulum but not lung-stage schistosomulum, adult, or egg and was localized to head gland, penetration gland tubes, and penetration glands where Ca(2+) was abundant, and the cercarial tegument (but not tegument of tail) and body-tail junction. Furthermore, SjCa8 was interestingly detected in cercarial secretions. The characterization of SjCa8 indicated that it may undergo structural and physiological modifications, including repair of the surface membrane, changes in permeability that account for the loss of water tolerance, activities of calcium-depending enzymes, and immune signaling, etc. Furthermore, vaccination with rSjCa8 plus adjuvant induced protective effect with 50.39% worm reduction rate and significantly high hepatic and intestine egg reduction rates (54.16%, 50.63%, respectively), which is possibly mediated through an apparent induction of Th1-type immune response for strikingly high level of IgG2a and IgG2b developed in immunized C57BL/6 mice.