[Construction and pathological characterization of 3 animal models of temporomandibular joint degenerative joint disease in mice]

Objective: To explore the pathological characteristics of three mice models of temporomandibular joint degenerative joint disease (TMJDJD), including osteoarthritis and osteoarthrosis, and to provide references for animal experimental study regarding the pathological mechanism of osteoarthritis and osteoarthrosis. Methods: A total of 54 8-week-old male C57BL/6 mice were selected to construct three TMJDJD animal models, including bilateral temporomandibular joint (TMJ) Freund's complete adjuvant (FCA) injection model, bilateral TMJ monosodium iodoacetate (MIA) injection model, and right TMJ discectomy model. FCA injection model (15 mice) was divided into saline injection group, FCA injection group-1 week, FCA injection group-2 week, FCA injection group-4 week and FCA injection group-6 week, 3 mice were used at each time point, with a total of 6 TMJs on both sides. MIA injection model (15 mice) was separated into saline injection group, MIA injection group-1 week, MIA injection group-2 week, MIA injection group-4 week and MIA injection group-6 week, 3 mice were used at each time point, with a total of 6 TMJs on both sides. TMJ discectomy model (24 mice) was split into control group, discectomy group-2 week group, discectomy group-4 week and discectomy group-6 week, six mice were used at each time point, with a total of six right TMJs. General pictures of the bilateral joints area of mice were collected 1 day after drug injection, and stereoscopic images of condylar tissues were collected 4 weeks after microsurgery for discectomy. Mouse TMJ tissue sections from each time point were stained with HE and toluidine blue, respectively, synovial tissues were scored for synovial inflammation, and the percentage of proteoglycan in condylar cartilage was quantitatively analyzed. Results: One day after intra-articular FCA or MIA injection, the width of bilateral TMJ were significantly increased in FCA injection groups [(24.60±0.46) mm] compared with the saline injection group [(21.63±0.52) mm] (t=4.25, P<0.013), the width of bilateral TMJ in MIA injection groups [(24.50±0.62) mm] were also significantly higher than that in saline injection group [(21.40±0.52) mm] (t=3.82, P=0.019). The synovitis scores in FCA injection groups 1, 2, 4, 6 weeks after FCA injection were significantly higher than that of the saline injection group (F=18.09, P<0.001), with the proteoglycan of condylar cartilage increased firstly and then decreased compared with the saline injection group (F=21.59, P<0.001). Condylar cartilage proteoglycan loss in different degrees were observed 1, 2, 4 and 6 weeks after MIA injection (F=13.59, P<0.001), and synovitis scores were increased at different degrees compared with saline injection group (F=14.79, P<0.001). The morphology of condylar cartilage in discectomy groups mice were severely damaged, synovial tissues showed dense connective tissue lesions at 2, 4 and 6 weeks postoperatively, condylar cartilage tissues showed a time-dependent loss of proteoglycan compared with the control group (F=40.62, P<0.001). Conclusions: Intra-articular FCA injection establishes a mouse model of TMJ osteoarthritis with severe synovial inflammation. Intra-articular MIA injection constructs a mouse model of typical TMJ osteoarthritis. Discectomy establishes a mouse TMJ osteoarthrosis model with severe condylar cartilage destruction.

The effectiveness of eHealth interventions on moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants: a systematic review and meta-analysis

Background

Cardiac rehabilitation is a class IA recommendation for patients with cardiovascular diseases. Physical activity is the core component and core competency of cardiac rehabilitation programs. Cardiac rehabilitation guidelines recommend patients achieve at least thirty minutes of moderate-to-vigorous intensity physical activity five or more days per week. However many patients with cardiovascular diseases are failing to meet recommended daily physical activity levels. eHealth interventions may increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants.

Objectives

The objective of this study was to review the evidence of the effectiveness of eHealth interventions to increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. The secondary objective was to examine the effectiveness of eHealth interventions on improving exercise capacity, cardiovascular risk profile and health-related quality of life.

Methods

A comprehensive search strategy was developed for four electronic databases (PubMed, Web of Science, Embase and The Cochrane Library); through December 16, 2021. All studies reporting on eHealth interventions designed to increase moderate-to-vigorous physical activity among cardiac rehabilitation participants were included. Multiple not-blind reviewers determined study eligibility and extracted data. Risk of bias was evaluated using the Cochrane Collaboration Tool for randomized controlled trials and using the Effective Practice and Organisation of Care Cochrane Review Group for non-randomized controlled trials. Data quality using the Grading of Recommendations Assessment, Development and Evaluation professional guideline development tool. Data were pooled using a random-effects model. All statistical analyses were performed using Stata 17.

Results

Twenty-one studies were included in the review which fifteen were in the meta-analysis. The meta-analysis demonstrated eHealth interventions improved moderate-to-vigorous physical activity (standard mean difference = 0.17, 95% confidence interval: 0.07, 0.27, P&lt;0.001). No changes were observed in exercise capacity (P=0.09), cardiovascular risk profile (body mass index, P=0.19; waist circumference, P=0.7; systolic blood pressure, P=0.36; total cholesterol, P=0.72; plasma glucose, P=0.41) and health-related quality of life (P=0.12).

Conclusions

eHealth interventions are effective at increasing minutes/week of moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. Future high-quality empirical studies are needed to evaluate the effectiveness of eHealth interventions delivered, with these sub-types (wearable devices, online web portal, smart phone application, messaging services and telephone calls) delivered alone or in combination delivered more conducive to moderate-to-high intensity physical activity.

Funding Acknowledgement

Type of funding sources: None.

Experimental Evidence of Intrinsic Current Generation by Turbulence in Stationary Tokamak Plasmas

High-β_{θe} (a ratio of the electron thermal pressure to the poloidal magnetic pressure) steady-state long-pulse plasmas with steep central electron temperature gradient are achieved in the Experimental Advanced Superconducting Tokamak. An intrinsic current is observed to be modulated by turbulence driven by the electron temperature gradient. This turbulent current is generated in the countercurrent direction and can reach a maximum ratio of 25% of the bootstrap current. Gyrokinetic simulations and experimental observations indicate that the turbulence is the electron temperature gradient mode (ETG). The dominant mechanism for the turbulent current generation is due to the divergence of ETG-driven residual flux of current. Good agreement has been found between experiments and theory for the critical value of the electron temperature gradient triggering ETG and for the level of the turbulent current. The maximum values of turbulent current and electron temperature gradient lead to the destabilization of an m/n=1/1 kink mode, which by counteraction reduces the turbulence level (m and n are the poloidal and toroidal mode number, respectively). These observations suggest that the self-regulation system including turbulence, turbulent current, and kink mode is a contributing mechanism for sustaining the steady-state long-pulse high-β_{θe} regime.

[Analysis on characteristics of HIV-1 molecular network in injected drug users in Guangzhou, 2008-2017]

Objective: To understand the characteristics of the HIV-1 molecular networks in injected drug users (IDUs) in Guangzhou from 2008 to 2017, and provide reference for the prevention and control of AIDS in this population. Methods: The serum samples of newly diagnosed HIV-1 positive IDUs in Guangzhou from 2008 to 2017 were collected, HIV-1 RNA was extracted for pol gene amplification and sequencing. The molecular cluster in the phylogenetic tree was identified by Cluster Picker 1.2.3 for cluster analysis. TN93 model in HyPhy2.2.4 was used to calculate the gene distance between the cluster sequences. Software Cytoscape3.8.2 was used to visualize the molecular network, and χ² test or exact probability method was used for cluster analysis and centrality analysis. Results: A total of 586 sequences were successfully amplified (73.9%, 586/793), and 80 molecular clusters were produced, with a clustering rate of 46.6% (273/586). In molecular clusters, the proportions of the strains from IDUs in Han ethnic group (48.4%, 260/537), IDUs who were local residents in Guangdong (52.7%, 146/277) and IDUs whose strain sequence subtype was CRF55_01B (93.3%, 14/15) were higher. In the molecular network, the degree range was 1-7, and nodes with degree ≥3 accounted for 12.8% (24/187), which was associated with another 81 nodes in the molecular network (43.3%, 81/187). The centrality analysis showed that the proportions of housework/unemployed with high degree centrality (19.0%, 19/100), high intermediary (22.0%, 22/100), and high proximity centrality (32.0%, 32/100) were higher in IDUs infected with HIV-1. Conclusion: The risk of HIV-1 clustering in IDUs in Guangzhou was high, suggesting that IDUs who were from both Guangdong and Guangxi and were house workers or unemployed should be viewed as the key targets, and precise intervention should be implemented to reduce the HIV-1 infection rate in this population.

Thermo-Responsive Shape Memory Behavior of Methyl Vinyl Silicone Rubber/Olefin Block Copolymer Blends via Co-Crosslinking

Shape memory polymers (SMPs) are developed by blending and cross-linking polymers which include crystalline domains and cross-linked networks. In this paper, we describe the morphology, thermal and shape memory behavior of methyl vinyl silicone rubber (MVMQ)/olefin block copolymer (OBC) blends prepared by a melt-blending and chemical cross-linking method. MVMQ without crystalline domains could not hold its temporary shape. After introducing the OBC, the obtained blends exhibited excellent dual shape memory properties. The cross-linking networks of MVMQ acted as reversible domains, while crystalline regions of OBC worked as fixed domains. When the blending ratio of MVMQ/OBC was 50/ 50, the blend had both a high shape fixity ratio and shape recovery ratio.

Role of the active cycle of breathing technique combined with phonophoresis for the treatment of patients with chronic obstructive pulmonary disease (COPD): study protocol for a preliminary randomized controlled trial

Background

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease characterized by coughing, the production of excess sputum, and dyspnea. Patients with excessively thick sputum may have frequent attacks or develop more serious disease. The guidelines recommend airway clearance for patients with excessive sputum who are hospitalized with COPD. The active cycle of breathing technique is the most common non-pharmacological airway clearance technique used by physiotherapists. However, the effectiveness of the technique is not always guaranteed. Active cycle of breathing techniques require the initial dilution of the sputum, usually by inhalation drugs, which may have limited effects. Recent studies have found that phonophoresis decreases inflammation, suggesting the potential of the combined usage of active cycle of breathing techniques and phonophoresis. Therefore, the aim of this study is to explore the effectiveness and safety of combining active cycle of breathing technique and phonophoresis in treating COPD patients.

Methods and analysis

We propose a single-blind randomized controlled trial using 75 hospitalized patients diagnosed with COPD with excessive sputum production. The patients will be divided into three groups. The intervention group will receive active cycle of breathing techniques combined with phonophoresis. The two comparison groups will be treated with active cycle of breathing techniques and phonophoresis, respectively. The program will be implemented daily for 1 week. The primary outcomes will be changes in sputum viscosity and production, lung function, and pulse oximetry. Secondary outcomes include the assessment of COPD and anxiety, measured by the COPD Assessment Test scale and the Anxiety Inventory for Respiratory Disease, respectively; self-satisfaction; the degree of cooperation; and the length of hospital stay. All outcome measures, with the exception of sputum production and additional secondary outcomes, will be assessed at the commencement of the study and after 1 week’s intervention. Analysis of variance will be used to investigate differences between the groups, and a p-value of less than 0.05 (two-tailed) will be considered statistically significant.

Discussion

This study introduces a combination of active cycle of breathing techniques and phonophoresis to explore the impact of these interventions on patients hospitalized with COPD. If this combined intervention is shown to be effective, it may prove to be a better treatment for patients with COPD.

Trial registration

The trial was registered prospectively on the Chinese Clinical Trial Registry on 24 December 2019.ClinicalTrials.gov ChiCTR1900028506. Registered on December 2019.

Role of active cycle of breathing technique for patients with chronic obstructive pulmonary disease: A pragmatic, randomized clinical trial

BACKGROUND

While active cycle of breathing technique for chronic obstructive pulmonary disease patients with more sputum can improve clinic outcomes, less is known about sputum viscosity and sputum production of the intervention.

OBJECTIVE

The purpose of our study was to explore the effect of active cycle of breathing technique on sputum viscosity and production among patients with chronic obstructive pulmonary disease.

DESIGN

This was a two-arms, parallel, randomized clinical trial.

SETTING

Study enrollment, randomization and implementation were conducted in the department of respiratory medicine inpatient at the Medical Center in Changchun, China.

PARTICIPANTS

Hospitalized patients due to chronic obstructive pulmonary disease who met additional eligibility criteria were randomized to active cycle of breathing technique (n = 50) or usual care group (n = 50).

METHODS

Patients in the intervention group received a week-long intervention from an experienced physical therapist. Patients in the usual care group received usual care as well as information and advice in the light of their health plan from respiratory medicine. The primary outcome was the changes on sputum viscosity and production.

RESULTS

Among one hundred patients who were randomized (mean [SD] age, 54.89 [12.06] years; females, 58%), ninety-six participants completed the study. No significant differences were found between two groups on the changes of sputum viscosity (t = 0.277, P = 0.782). And there were insignificant differences between groups in the average amount of sputum among 1 h (Z=-1.848, P = 0.065) and significant differences in the average amount of sputum among 24 h (Z=-2.236, P = 0.025). From admission to one week recovery, the changes in ratio of forced expiratory volume in 1 s to forced vital capacity (Z=-4.511, P<0.0001) and arterial oxygen saturation (Z=-2.997, P = 0.003) were better in active cycle breathing technique group. Total Chronic Obstructive Pulmonary Disease Assessment Test scale were similar among two groups (Z=-1.818, P = 0.069). No adverse events occurred during the study.

CONCLUSION

For patients with chronic obstructive pulmonary disease, active cycle of breathing technique can significantly result in sputum production and respiratory function, especially those of Global Initiative for Chronic Obstructive Lung Disease classification level 3, but did not result in the short-term improvement of sputum viscosity, quality of life and cost effectiveness. Registration number: ChiCTR2000033068.

Preparation, Foaming and Characterization of Poly(l-lactic acid))/Poly(d-lactic acid)-Grafted Graphite Oxide Blends

Commercial poly(l-lactic acid) (PLLA) was blended with different contents of graphene oxide-graft-poly(d-lactic acid) (GO-g-PDLA), which was synthesized via ring-opening polymerization using modified GO as initiator. PLLA and PLLA/GO-g-PDLA blend foams were prepared in a batch process via varying-temperature mode using supercritical carbon dioxide as physical foaming agent. The results showed that the addition of GO-g-PDLA in PLLA leads to the formation of stereocomplex (sc)-crystallites. Increase in the GO-g-PDLA content enhances the IR absorption, diffraction peak and melting peak corresponding to the sc-crystallites. The addition of GO-g-PDLA to PLLA leads to the decrease of the cell diameter, increase of the cell density and to a little change in expansion ratio, which is attributed to the fact that the enhancement of PLLA crystallization restricts cell growth and GO-g-PDLA acts as nucleation point.

[Etiologic characteristics of Shigella sonnei strains isolated from some areas of Guangdong province and Guangxi Zhuang Autonomous Region of China, 2014-2016]

Objective: To investigated the etiologic characteristics of Shigella (S.) sonnei strains causing outbreaks and sporadic cases in some areas of Guangdong province and Guangxi Zhuang Autonomous Region during 2014-2016. Methods: Fourteen S. sonnei strains isolated from outbreaks and 6 S. sonnei strains from sporadic cases from Guangdong and Liuzhou of Guangxi Zhuang Autonomous Region were tested for antimicrobial resistance and analyzed by pulsed-field gel electrophoresis (PFGE). Six typical strains were selected for whole genome sequencing typing and compared with 51 strains isolated both at home and abroad from NCBI genome database. Results: The antibiotic resistance test indicated the isolates had high resistance rate to ampicillin, tetracycline, gentamicin, trimethoprim/sulfamethoxazole and nalidixic acid, while sensitive to azithromycin, chloromycetin and imipenem. PFGE showed high similarity (93.2%) among the strains isolated from different areas. The whole genome sequencing analysis also revealed that all the typical strains were clustered into a same evolution branch, close to some strains from Korea. Conclusions: The S. sonnei strains isolated from some areas of Guangdong and Guangxi Zhuang Autonomous Region showed high resistance to commonly used antibiotics, but they were sensitive to azithromycin, chloramphenicol and imipenem. The isolates in this study also showed similar PFGE patterns and close phylogenic evolution.

Operation of bolometer system using Pt foil on SiN substrate detector for EAST tokamak

The foil resistive bolometer diagnostic on experimental advanced superconducting tokamak has been upgraded partly with a new generation of detectors. The new detectors have faster response time. However, the microwave interference is still a serious issue for the bolometer system. The system response to microwave is tested, and the test results show that the closed Wheatstone bridge circuit in the detector is the most sensitive component to high power microwave field. Simulation results of microwave transmission by the high frequency structure simulator software and shielding design are also presented.

Ethylene Methyl Acrylate Copolymer Toughened Poly(lactic acid) Blends: Phase Morphologies, Mechanical and Rheological Properties

The ethylene methyl acrylate copolymer (EMA), for the first time, was melt blended with poly(lactic acid) (PLA) by a twin-screw extruder to toughen PLA. The phase morphologies, mechanical, and rheological properties of the PLA/EMA blends with six weight ratios were investigated. The results showed that the addition of EMA improves the toughness of PLA at the expense of the tensile strength, flexural strength and modulus to a certain degree, and results in the transition from brittle fracture of PLA into ductile fracture. The droplet-matrix morphology is observed in the PLA/EMA blends, in which the mean diameter of EMA droplets increases and its distribution widens gradually with increasing the EMA content. The PLA/EMA blends with three weight ratios (90/10, 80/20, and 70/30) display different characteristic linear viscoelastic properties in the low frequency region, which were investigated in terms of their complex viscosity, storage modulus, and Cole-Cole plots. The interfacial tension between the PLA and EMA is calculated using the Palierne model conducted on the 80/20 PLA/EMA blend, and the calculated result is 3.3 mN/m.

Optical and magneto-optical anisotropies in large-area two-dimensional Co antidots film

In this work, we investigate the plasmon-induced optical and magneto-optical anisotropies in the large-area square-ordered Co antidots film. It shows that both the outline of reflectivity spectrum and Kerr spectrum are significantly modified by surface plasmon polarition (SPP) resonances. Moreover, the magnitude of Kerr angle reaches to about 10 minutes at the azimuthal angle 45°, which is over 3 times of that of pure Co film. These phenomena are attributed to the SPP resonances with different diffraction orders of reciprocal lattice vectors.

Distribution of radionuclides in the guano sediments of Xisha Islands, South China Sea and its implication

Several natural and anthropogenic radionuclides ((210)Pb, (226)Ra and (137)Cs) in guano-phosphatic coral sediments and pure guano particles collected from Ganquan, Guangjin, Jinqing and Jinyin Islands of the Xisha archipelago, South China Sea, were analyzed. The Constant Initial Concentration (CIC) model and the Constant Rate of Supply (CRS) model were applied for age calculation. The average supply rate of (210)Pb was 126 Bq m(-2) a(-1), very close to the flux of northern hemisphere average (125 Bq m(-2) a(-1)). The activities of anthropogenic radionuclides in the sediments were very low, indicating that human nuclear tests did not notably impact this region. The main source of radionuclides in the sediments was from atmospheric precipitation, and the organic matter derived from plant and produced by nutrient-rich guano could further enhance them.

Smart nanofibers from combined living radical polymerization, "click chemistry", and electrospinning

A simple method for preparing solvent-resistant nanofibers with a thermal-sensitive surface has been developed by the combined technology of reversible addition-fragmentation chain-transfer (RAFT) polymerization, atom transfer radical polymerization (ATRP), electrospinning, and "click chemistry". Initially, well-defined block copolymers of 4-vinylbenzyl chloride (VBC) and glycidyl methacrylate (GMA) (PVBC-b-PGMA) were prepared via RAFT polymerization. Electrospinning of PVBC-b-PGMA from a solution in tetrahydrofuran gave rise to fibers with diameters in the range of 0.4-1.5 microm. Exposure to a solution of sodium azide (NaN(3)) not only affords nanofibers with azido groups on the surface but also leads to a cross-linking structure in the nanofibers. One more step of "click chemistry" between the PVBC-b-PGMA nanofibers with azido groups on the surface (PVBC-b-PGMA(-N3)) and alkyne-terminated polymers of N-isopropylacrylamide (NIPAM) (PNIPAM(AT)), which were prepared by ATRP, allows the preparation of a PVBC-b-PGMA nanofiber with thermal-sensitive PNIPAM brushes on the surface (PVBC-b-PGMA-g-PNIPAM). PVBC-b-PGMA-g-PNIPAM nanofibers exhibit a good resistance to solvents and thermal-responsive character to the environment, having a hydrophobic surface at 45 degrees C (water contact angle approximately 140 degrees) and having a hydrophilic surface at 20 degrees C (water contact angle approximately 30 degrees).

Superficial peroneal sensory and sural nerve conduction studies in peripheral neuropathy

The objective of this study was to prospectively evaluate sensory nerve conduction studies (NCS) in the distal lower limbs in the electrodiagnosis of peripheral neuropathy. We prospectively studied 316 consecutive patients with surface stimulation and recording, in comparison with 90 control subjects. A total of 310 patients were found to have lower limb sensory NCS abnormalities. In these patients, the rate of detection of peripheral neuropathy with superficial peroneal NCS (88.5%) was significantly higher (P<0.001) compared with sural NCS (75%). The superficial peroneal NCS appeared to have a higher detection rate for peripheral neuropathy in our study, and its study can be adjunctive to sural NCS.

Short-segment nerve conduction studies in the localization of ulnar neuropathy of the elbow: Use of flexor carpi ulnaris recordings

Short-segment nerve conduction studies were performed in 17 limbs with clinical features suggestive of ulnar neuropathy at the elbow. Recording from flexor carpi ulnaris yielded 93% sensitivity, compared with 71.4% when recording from abductor digiti minimi. The rationale underlying the technique is discussed. This approach should be of value as a diagnostic adjunct in technically challenging cases of ulnar neuropathy at the elbow.

Posterior antebrachial cutaneous nerve conduction study in radial neuropathy

Radial neuropathy most commonly occurs as a result of external compression at the spiral groove region. The posterior antebrachial cutaneous nerve (PACN) conduction study was performed in 15 consecutive patients with radial palsy. Unilateral PACN abnormalities were present in 11 patients. A normal PACN study was correlated with clinical improvement at 3 months. Conversely, PACN abnormality was correlated with radial motor axon loss and a poorer prognosis. The PACN study is a simple adjunct which provides additional information relating to the diagnosis and prognosis of radial lesions.

Posterior antebrachial cutaneous nerve conduction studies in normal subjects

OBJECTIVE

The posterior antebrachial cutaneous (PABC) nerve is a sensory nerve that branches out from the radial nerve at the level of the spiral groove. Thus it can be affected in a radial nerve lesion at or proximal to its origin in the spiral groove. However, there has been limited knowledge about the normal values of PABC nerve conduction studies. This study was done to determine these normal values.

METHODS

Sixty-three healthy adults (23 males) with a mean age of 41.5+/-10.6 (range, 20-90) years were recruited with informed consent. A total of 126 nerves were studied. The nerve conduction studies were performed using a Dantec Counterpoint EMG machine (Dantec, Skovlunde, Denmark).

RESULTS

The mean+/-standard deviation values for the onset as well as peak latency, conduction velocity, amplitude and side-to-side amplitude ratio were 2.07+/-0.16 (range, 1.80-2.60) ms, 2.35+/-0.15 (range, 2.05-2.90) ms, 58.21+/-4.29 (range, 46.15-66.67) m/s, 6.10+/-2.11 (range, 2.90-13.00) microV and 0.83+/-0.12 (range, 0.60-0.99), respectively. There was a significant correlation between the subject age and the PABC onset and peak latencies as well as the amplitudes.

CONCLUSIONS

The PABC nerve is assessable for nerve conduction studies and these normal values may be useful in evaluation of patients with suspected radial nerve lesions.

[On cleanliness of hands in diminution of Ascaris lumbricoides infection in children]

OBJECTIVE

To study the relationship between cleanliness of children's hands and diminution of Ascaris lumbricoides infection.

METHODS

Before the study all persons positive for ascaris eggs in the preliminary survey were treated with albendazole. Hand-washing habit before meal and after defecation was kept in children of experimental group, but not in the control group. Kato thick smear stool examination was done once every two months for one year to compare the new infection rates in children without ascaris infection in the two groups, and the reinfection rates in the cured negative cases were also compared between them in half a month after chemotherapy.

RESULTS

All the new infection rates as well as reinfection rates of each reexamination in the experimental group were significantly lower than that of the control group (P < 0.001). Reexamination one year later showed that the ascaris infection rate of the experimental group was 35.2%, reducing by 48.5% as compared with 68.3% before the operation of the project; while ascaris infection rate of the control group was 73.7%, increasing by 78.0% as compared with 41.4% before the operation of the project.

CONCLUSION

Washing hands with toilet soap to keep hands clean can significantly reduce ascaris infection rate.

Infantile hookworm disease in China. A review

Hundreds of cases of infantile hookworm disease which shows bloody stools, melena, anorexia, listlessness and oedema, have been reported in China since the 1960s. Hookworm eggs were detected in due course in the faeces of the reported cases. With the exception of a single worm identified as Necator americanus, all the adult worms expelled following chemotherapy or examined at autopsy were Ancylostoma duodenale. Many children showed clinical manifestations and eggs in their faeces on day 1-26 after birth, and more cases occurred within 3 months of birth. Evidently, these infections were mostly transmitted from the mothers by transplacental and/or transmammary routes.

Soil-transmitted helminthiases: nationwide survey in China

A total of 2848 study sites, with about 500 people in each, were randomly sampled for this investigation which covered a total population of 1 477 742. By stool examinations using the Kato-Katz thick-smear and larval-culture techniques, overall prevalences of 47.0%, 18.8%, and 17.2% were obtained for Ascaris lumbricoides, Trichuris trichiura, and hookworm infections, respectively. The number of infections due to Ascaris, Trichuris, and hookworm was estimated as 531 million, 212 million, and 194 million, respectively. Egg counts showed that 75-95% of the subjects had light infections. Higher prevalences of ascariasis and trichuriasis were found in the age group of 5-9, 10-14 and 15-19 years, and among adults for hookworm. Students, farmers (including vegetable growers) and fishermen were the occupational groups with high infection rates. The prevalence of helminthiases was found to be closely associated with climatic and geographical factors. In view of the morbidity and mortality due to these helminthiases, their control, particularly in schoolchildren, is very important.

Nationwide survey of human parasite in China

A nationwide survey of human parasites in China was conducted during 1988-1992, with a coverage of 30 provinces/autonomous regions/municipalities (P/A/M). A total of 2,848 pilot sites in 726 counties were selected by random sampling, and 1,477,742 individuals residing on were surveyed by fecal examination. The status of paragonimiasis, hydatid diseases, cysticercosis and trichinellosis were summarized through data review. The overall infection rate of intestinal parasites was 62.6% whereas at provincial level, the highest infection rate (94.7%) was recovered in Hainan, and the lowest (17.5%) in Heilong-jiang. A high proportion (43.3%) of polyparasitism among the infected population (882,080) was revealed. Altogether 56 species of parasites comprising protozoa (19), trematode (16), cestodes (8), nematodes (12) and thorny-headed worm (1) were discovered. During the survey a new species and several new records were documented. The number of the population infected with common intestinal parasites was estimated. The diversities of parasite distribution were noted in different nationalities as well as in varied occupations.

Selenium in Kashin-Beck disease areas

In this article, the duplication portion technique was used to determine the daily intakes of selenium and ten other elements in the 24-h total diets collected in the typical Kashin-Beck endemic areas, i.e., Shanxi Province and Inner Mongolia Autonomous of China. The contents of Ca, Mg, Cu, Fe, Zn, Mn, Al, Sr, Ba, and P in freeze-dried samples were determined by ICP-AES. Se was determined by differential pulse catalytic polarography. The average Se contents in total diets of Shanxi Kashin-Beck endemic and nonendemic areas were 0.009 and 0.021 micrograms/g (dry weight), respectively (P less than 0.001), corresponding to the daily intakes for Se of 4.6 and 10.5 micrograms. After the Se-supplemented fertilizer was applied (225 g of Na2SeO3/ha), the average Se content in total diets of Kashin-Beck disease area was increased to 0.0336 micrograms/g, which corresponded to the average daily intake for Se of 16.8 micrograms. In Inner Mongolia Kashin-Beck endemic and nonendemic areas, the average Se contents in total diets were 0.006 and 0.017 micrograms/g, respectively (p less than 0.001), corresponding to the average daily intakes for Se of 3 and 8.5 micrograms. The contents of other ten elements in total diets in endemic and nonendemic areas were reported and compared.

Antagonism between selenium and humic acid

In this work, two groups of experiments have been done by using mice and luminous bacteria. The results show that there exists an antagonism in toxicity between selenium and humic acid (HA) extracted from the drinking water in Kaschin Beck disease regions. In order to study the chemical mechanism of the antagonism, gel filtration and X-ray photoelectron spectroscopy techniques have been used to study the chemical bonding of the synthetic HA-Se in solution. The relationship between Se and HA in the cause of Kaschin Beck disease is discussed.