Table of Content

30 November 1990, Volume 8 Issue 4

Previous Issue    Next Issue

EPIDEMIOLOGICAL SURVEY ON PATIENTS WITH ADVANCED FILARIASIS IN SHANDONG PROVINCE WITH BANCROFTIAN FILARIASIS BASICALLY ELIMINATED

1990, 8(4):  245-248. 

Asbtract ( )   PDF (270KB) ( )  

Related Articles | Metrics

This paper reports on the incidence of advanced filariasis after basic elimination of bancroftian filariasis since 1983 in Shandong Province. Investigation was carried out in a population of 166 776 between 1984 and 1988 in 252 villages of Teng Xian and other 5 counties/cities, the erstwhile highly endemic areas. A total of 1038 filariasis patients were found with an average incidence of 0.6%. Among them, 383 were with elephantiasis, 357 with chyluria and 298 with hydrocele. 902 cases (86.9$) who suffered the disease before the elimination of filariasis and 136 cases (13.1%) after it, 125 (91.9%) being chyluria cases. The oldest of the 1 038 cases was 86 years of age and the youngest, 6 years of age. The course of duration as 8~74 years in elephantiasis cases, 82.8% of them (317 cases) had previously lymphangitis and/or lymphadenitis. In the past three years 16.4% (52 cases) suffered from prolonged or intermittent acute lymphangitis and/or lymphadenitis. The results of this survey indicated that, after the basic elimination of filariasis in Shandong Province together with thorough clearance of infection source, elephantiasis and hydrocele persisted while new cases of chyluria continued to develop. Therefore, in such areas more emphasis should be put on the treatment of clinical patients. New patients should be surveyed and old patients be treated actively so as ta reach the goal of eradicating filariasis.

CONSTRUCTION OF A cDNA LIBRARY OF SCHISTOSOMA JAPONICVM

1990, 8(4):  249-252. 

Asbtract ( )   PDF (1167KB) ( )  

Related Articles | Metrics

The template mRNA was extracted from Schistosoma japonicum. The first strand of cDNA was synthesized by AMV-reverse transcriptase. The second strand cDNA was first digested by RNase H to remove mRNA and was then synthesized by AMV-reverse tran-scriptase, T4-DNA polymerase- Sizing of cDNA was applied on a NACS column to remove small fragments of less than 1 kb. Homopolymeric tailing of vector (PUC18) was done with dGTP and DNA terminal transferase and tailing of the cDNA with dCTP was carried out under the same conditions. After annealing, the plasmids with cDNA were transformed into E. coli MC1061. The efficiency of cloning was about 104/μg mRNA with 30% of the transformants having the inserts of cDNA (Figs. 1-2).

CHANGES IN THE SUSCEPTIBILITY OF THE RECIPIENT AEDES AEGYPTI TO BRUGIA PAHANGI AFTER PASSIVE TRANSFER OF HAEMOLYMPH

1990, 8(4):  253-255. 

Asbtract ( )   PDF (236KB) ( )  

Related Articles | Metrics

Observations were carried out on the changes in the susceptibility of Aedes aegyptt (refm) to Brugia pahangi after receiving haemolymph from both refractory (repRR) and susceptible (refm) Aedes aegypti that were previously inoculated with microfilariae plus TC199 (tissue culture 199) or TC199 respectively. The metanization rates of microfilariae in the recipient mosquitoes were determined by dissecting the mosquitoes on day 3, 4 and 5 after haemolymph transfer. In the recipients receiving haemolymph from the refractory donors inoculated with microfilariae plus TC199, from the refractory donors inoculated with TC199 only and from the susceptible donors inoculated with TC199 only, the melanization rates of microfilariae were estimated to be 31.2%, 31.1% and 21.2% respectively. It is suggested that the intensity of melanization of mosquitoes varies with their susceptibijity inherited from their parents. Therefore, the melanization rates of microfilariae in the mosquitoes can be taken as one of the indices of their susceptibility. In addition, most (64.3-73.6%) of the recovered melanized microfilariae were found in the abdomen of the mosquitoes while almost all the developing larvae, in the thorax, possibly due to the choice of preferred sites for development in the latter.

IN VITRO ASSAY FOR DETECTING HEMOLYTIC TOXICITY OF ANTIMALARIALS INCORP RATED WITH MICROSOMAL METABOLIC SYSTEM

1990, 8(4):  256-259. 

Asbtract ( )   PDF (309KB) ( )  

Related Articles | Metrics

The in vitro metabolic system comprised NADP co-factors and liver microsomes isolated from male rats pre-treated with phenobarbital, 60 mg/kg, i.p for 3d combined with a single i.p. dose of 80 mg/kg of naphtholflavone. The 1% RBC suspension was made up from G6PD-defitient rabbit blood. Primaquine, chloroquine and M 8506 at various dosages were incubated at 37℃ with the microsomal metabolic system in vitro respectively. The supernatants were incubated with 1% RBC suspension. The OD635nm values of tbe supernatants were detected after incubation and centrifugation. The results showed that both primaquine and M 8506 exhibited potent hemolytic toxicity at the dose-range of 1.5 -3 × (101-103) μmol/L, with certain dose-effect relationship, while chloroquine exhibited no hemolytic toxicity. It is suggested that the in vitro assay incorporated with microsomal metabolic system might be a useful preliminary screening method for testing hemolytic toxicity of various antimalarials.

EXPERIMENTAL INFECTION INDEX OF ANOPHELES SINENSIS AND MELANIZATION OF PERIODIC BRUGIA MALAYI LARVAE

1990, 8(4):  260-263. 

Asbtract ( )   PDF (302KB) ( )  

Related Articles | Metrics

This paper deals with the infection index of Anopheles sinensis infected with the blood meals of 9 different microfilarial densities (5-300 mf/10μl) of periodic Brugia malayi. The results indicated that the mean number of microfilariae (mf) ingested by mosquitoes increased with the mf-density of the blood meal. The infection rates of vectors were 30, 65, 93 and 100%, when mf-densities were 5, 10, 20 and 50 mf/10μl respectively. Although the infection rate was 100% when mf-densities were larger than 50(100, 150, 200, 250, 300) mf/10μl. the infection intensities were gradually increased from 17.2 to 51.4 and the host efficiencies were decreased from 0.4135 to 0.2328. The infection intensities and host efficiencies of low mf-densities (5, 10, 20, 50 mf/10μl) were 1.22-8.40 and 0.5669-0.6356 respectively. Under the condition of 27.5±0.5℃, RH75±5%, the developmental period from mf to third stage larva was 8 days and numerous infective larvae could be harvested when mf-density was 200 mf/10μl. The relationship between mf-density and host efficiency, number of melanized larvae and susceptibility of vector, (experimental infection indices of Kartman and of Wharton were discussed.

SCREENING OF SCHISTOSOMA JAPONICUM ADULT WORM GENOMIC DNA LIBRARY BY SPECIFIC ANTIBODY

1990, 8(4):  264-266. 

Asbtract ( )   PDF (1082KB) ( )  

Related Articles | Metrics

S. japonicum adult worm genomic DNA libraries were screened by enzymeimmunoassay. The antigens produced by recombinant λgt 11 plaques were transferred to nitrocellulose filters. Clones encoding given antigens were detected with infected rabbit sera (IKS) which were preabsorbed with lysate of induced λgt 11 in Y1090 cells. Eight putative positives were picked up from 97 plates in the primary screening and were rescreened a second time, and, 2 of them consistently gave good positive signals in subsequent screenings. One of the phage clones was purified to homogeneity and mixed with Y1089 cells. The expressed products still showed positive when rescreened by ELISA, indicating that the clone encor ding S. Japonicum antigen could be recognized by IRS. The immmunoscreening method described here was able to efficiently isolate single clones encoding S. japonicum antigens The method has the advantages of screening libraries efficiently, reliably and specifically, and it might open the way to screen genes encoding S. japonicum antigens inducing protective immunity (Fig. 1).

DOT-ELISA USING MONOCLONAL ANTIBODY FOR DETECTING SCHISTOSOME CIRCULATING ANTIGEN

1990, 8(4):  267-269. 

Asbtract ( )   PDF (241KB) ( )  

Related Articles | Metrics

Monoclonal antibodies were produced by the fusion of splenic lymphocytes from BALB/c mice immunized with Schistosoma japonicum excretory / secretory antigen and the myeloma cell line SP2/0. The 1B2E7B8 McAb was proved to be specific against the gut antigen of adult worm in IFA. The McAb labelled with HRP was used in Dot-ELISA to detect schistosome circulating antigen.Schistosome circulating antigen was detected in 152 out of 188 proven cases of schis-tosomiasis, accounting for a positive rate of 80.9%. The positive rates for circulating antigen in cases with 1-24, 25-99 and ≥100 EPG were 76.8%, 86.6% and 100% respectively. 10 out of 11 cases who had been checked 2 months after effective treatment became ELISA negative. No circulating antigen was detected in cases with other parasitosis nor in normal individuals. In addition, the McAb-Dot-ELISA showed good reproducibility The results indicated that McAb-Dot-ELISA might be used for diagnosis of schistosomiasis and evaluation of cure.

STUDIES ON THE STRAIN DIFFERENCES OF SCHISTOSOMA JAPONICUM IN THE MAINLAND OF CHINA Ⅱ.SUSCEPTIBILITY OF MAMMALIAN HOSTS

1990, 8(4):  270-273. 

Asbtract ( )   PDF (293KB) ( )  

Related Articles | Metrics

Six species of animals were percutaneously exposed to cercariae obtained from pools of naturally infected snails from different isolates of S. japonicum in the mainland of China as shown in Tables 1 and 2. Our results indicated that with the exception of rat, all animals under study were permissive host though their worm recovery rates varied with different isolates.The mean prepatent period in different host species were 35.0 ±0.8 to 36.4±1.0 days for Anhui isolate; 34.5±1.2 to 36.4± 1.2 days for Hubei isolate; 34.5±1.3 to 35.8 ±0.6 days for Sichuan isolate; 35.1 ± 1.0 to 37.3 ± 1.9 days for Guangxi isolate and 36.1 ±1.9 to 37.8 +± 0.8 days for Yunnan isolate. In general, the prepatent period was longer in the C57 BL inbred mice, hamsters and rhesus monkeys infected with Yunnan and Guangxi isolates, than that with Sichuan isolate. This result also indicates that the prepatent period of the strain of S. japonicum defined by Dr. Vogel as a Chinese strain which had been originated from the cercariae in infected Oncomelania hupensis hupensis snails from Jiaxing, Zhejiang (Kashing, Chekiang), China, and established in Tropeninstitut in Hamburg since 1937 by repeated passages in dogs and laboratory-bred O. h. hupensis snails, was 5-8 days longer than that of all the isolates under our study, probably due to some behavioral change. We suggest, therefore, that the Vogel's stock of S. japonicum should be termed as "Chinese Vogel strain".

IDENTIFICATION OF L. DONOVANI PROMASTIGOTES FROM PHLEBOTOMVS BY MONOCLONAL ANTIBODY

1990, 8(4):  274-276. 

Asbtract ( )   PDF (231KB) ( )  

Related Articles | Metrics

It has been reported by the authors that monoclonal antibody L12G9 produced from target antigens of L. donovani promastigotes, was very useful for detecting promastigotes from artificially infected sandflies. In the present study, detection of promastigotes from artificially infected sandflies by McAb showed that the positive rate correlated with the infection duration of sandflies. 4 days after feeding on infected Chinese hamsters, the sandflies were lightly infected with L. donovani promastigotes with a positive rate of 15.9%, but 10 days later, the sandflies were heavily infected, the positive rate being 100%:Observation has been made on the relationship between the number of promastigotes and mouse blood dilution. The results showed that satisfactory results could be obtained by using monoclonal antibodies in the detection of L. donovani, the number of promas tigotes should be over 1 × 107/ml, and the blood meals in sandflies completely digested.If very few promastigotes were present in naturally infected sandflies before identification by monoclonal antibody, the parasites must be grown in NNN medium. Positive result could then be obtained.

STUDIES ON THE DYNAMIC CHANGES IN SPECIFIC ANTIBODIES IN SERA FROM ANIMALS INFECTED WITH UNISEXUAL AND BISEXUAL CERCARIAE OF SCHISTOSOMA JAPONICVM

1990, 8(4):  277-280. 

Asbtract ( )   PDF (312KB) ( )  

Related Articles | Metrics

The IEST using both liver tissue-egg frozen section of mice infected with Schistosoma japonicum and adult worm frozen section of Schistosoma japonicum (TEFS-IEST and AWFS-IEST) were performed to study the dynamics of specific antibodies in sera from rabbits infected with unisexual and bisexual cercariae of Schistosoma japonicum. Both peaks of specific antibodies appeared at the 10th week after infection. The levels of specific antibodies were much higher in bisexual infection than in unisexual infection and closely related to the intensity and duration of infection. The levels of anti-egg antibodies were higher than those of anti-adult worm antibodies. The serological reactivity of egg antigen is higher than that of adult worm antigen. TEFS-IEST shows higher sensitivity and specificity than AWFS-IEST and DGS-COPT for the diagnosis of schistosomiasis.

fN VITRO CULTIVATION OF PLASMODIUM FALCIPARUM WITH UMBILICAL CORD ERYTHROCYTE

1990, 8(4):  281-283. 

Asbtract ( )   PDF (250KB) ( )  

Related Articles | Metrics

Plasmodium falciparum was cultivated with umbilical cord erythrocytes or with erythrocytes from human adults for 33 days and 50 days respectively. The erythrocyte infection rate increased eightfold to eighteenfold at intervals of three to four days, the highest erythrocyte infection rate being more than 20%. Furthermore, the infection rate of umbilical cord erythrocytes was higher than that of adult erythrocytes at 48, 72 and 96 hours of cultivation, respectively (P0.01). The results suggested that human umbilical cord blood might be a good source of erythrocytes for in vitro cultivation of malaria parasite.

ANALYSIS OF AMINO ACIDS IN HEMOLYMPH AND ACID HYDROLYSATES OF MIDGUTS OF ANOPHELES DIRVS INFECTED WITH PLASMODIVM CYNOMOLGI

1990, 8(4):  284-287. 

Asbtract ( )   PDF (318KB) ( )  

Related Articles | Metrics

Quantitative determinations of free amino acids in hemolymph and acid hydrolysates of midguts of female Anopheles dims infected with Plasmodium cynomolgi bastianellii were carried out and the results were compared with those of noninfected mosquitoes. On day 10 after infected blood meal, the contents of methionine, isoleucine, leucine, ornithine, lysine in the hemolymph of infected mosquitoes markedly decreased as compared with those in the controls. However, the quantitative analysis of the amino acids of the acid hydrolysates of the midguts from infected mosquitoes on day 9 after an infected blood meal showed that the content of their total amino acids was 70 % more than that in the controls, with special reference to aspartic acid, glutamic acid, valine, methionine, isoleucine, leucine, phenylalanine, tryptophan.

STUDY ON THE EXOERYTHROCYTIC FORMS OF PLASMODIUM YOELII YOELII IN RATS AND MICE

1990, 8(4):  288-290. 

Asbtract ( )   PDF (1230KB) ( )  

Related Articles | Metrics

SD rats and three strains of mice were infected with Plasmodium yoelii yoelii By265 strain by intravenous inoculation of sporozoites via tail vein. Liver tissues were taken 42 hours after infection and serial sections were made and stained by Colophonium-Giemsa method for microscopic examination. The ratio of the average value of major diameter/ minor diameter of exoerythrocytic(EE)schizonts of Plasmodium yoetii yoelii in rats and mice of ICR/JCL, C57BL, KM strains was 35.81 ±4.56μm/29.72±4.08μm, 28.08±4.66μm/23.66±4.44μm, 28.14±.16μm/23.63±3.77μm, 23.80±2.42μm/21±0μm, respectively. The results showed that the development of EE schizonts of Plasmodium yoelii yoelii was not synchronous. The EE schizonts in the rat liver were surrounded by Kupffer cells, monocytes and monocyte-derived macrophages. Since the parasitemia disappeared rapidly in rats, and EE schizonts were not well developed in KM strain, it may be considered that ICR/JCL and C57BL strains are more suitable as vertebrate host in Plasmodium yoelii yoelii-Anopheles stephensi system model (Figs. 1-9).

SCANNING ELECTRON MICROSCOPIC OBSERVATIONS ON LARVAE AND YOUNG ADULTS OF ANGIOSTRONGYLU8 CANTONENSIS

1990, 8(4):  291-294. 

Asbtract ( )   PDF (1592KB) ( )  

Related Articles | Metrics

Scanning electron microscopic observations on the structure of the body surface of various larval stages and young adults of Angiostrongylus cantonensis were made. The mouth opening of the first and second stage larvae closes in "Y" form until well developed young adult stage, There are two rows of 6 sensory papillae each around the mouth. With development of the worm, the papillae of the outer row gradually degenerated and could hardly be seen in adult worms. A pair of amphidial pores was present on the external side of lateral papillae of the inner row, being conspicuous in the fourth-stage larvae. There was one excretory pore on the ventral side of the anterior end. The copulatory bursa of the male worms began to develop in the third stage larvae and became well developed in the 25-day young adults. The processes of the development of copulatory bursa were described. The gonopore could be seen in the female worm as early as in the first-stage larvae but the anal pore appeared only in the fourth-stage larvae, both of them did not develop completely until the young adult stage of 11 day old (Figs. 1- 18);

ULTRASTRU CTURAL CHANGES IN THE BODY WALL AND GUT OF CLONORCHIS SINENSIS IN RATS AFTER ALBENDAZOLE TREATMENT

1990, 8(4):  295-297. 

Asbtract ( )   PDF (1101KB) ( )  

Related Articles | Metrics

The effect of albendazole on the body wall and gut of Clornorchis sinensis was studied with transmission and scanning electron microscopes after albendazole administration to rats infected with Chonorchis sinensis at a single dose of 150mg/kg. The results showed that swelling and adhesion of the projections of the tegument and gut microvilli occurred lh after medication. Necrosis and disruption of the projections and the gut microvilli were seen at the 24th h. By the 72nd h, detachment of the partial projections were seen. The dynamic process of the damages observed on the tegument was identical with that of the gut microvilli (Figs. 1-10).

AN APPROACH TO THE PATHOLOGIC BASIS OF ULTRASONOGRAPHY IN HEPATIC HYDATID DISEASE

1990, 8(4):  298-301. 

Asbtract ( )   PDF (316KB) ( )  

Related Articles | Metrics

The relationship between sonographic image and histological findings of 149 hepatic hydatid cysts was studied in 98 patients with primary hepatic hydatid disease. Sonographic classification was based on the morphology and structure of the cyst, which is thought to correspond to developmental stages of the hydatid cyst. The types were classified as follow: Type Ⅰ: simple fluid-filled cyst denoted as the early stage of the disease; Type Ⅱ: with undulated membrane representing detached endocysts secondary to rupture; Type Ⅲ: with daughter cysts and a formed echogenic material called matrix; Type Ⅳ: solid cyst filled with matrix; Type Ⅴ: calcified cyst. The latter two types were dead cysts, denoting the end of natural fate of the cyst. The natural progression of the cyst from Type Ⅰ to TypeⅤ was correlated with increasing age of the patients. The rate of stainable protoscolices corresponded to the degree of damage of the germinal membrane, which could reflect the viability of hydatid cyst. The damage of germinal membrane happened earlier and was more severe than that of the protoscolices?being the biologic basis of transforming from type Ⅱ into type Ⅲ. Our study also showed that normal, damaged and dead cysts accounted for about 1/3 respectively in the clinical cases of hepatic hydatid disease, providing references for evaluating chemotherapeutic effects on hepatic hydatidosis.

TUMOR NECROSIS SERUM INDUCE PLASMODIVM FALCIPARVM CRISIS FORM

1990, 8(4):  302-304. 

Asbtract ( )   PDF (228KB) ( )  

Related Articles | Metrics

This paper reports that tumor necrosis serum (TNS) containing tumor necrosis factor (TNF) could inhibite Plasmodium falciparum in vitro, TNS was obtained from rabbits given macrophage-activiting agent Mycobacterium tuberculosis (BCG)followed by intravenous administration of bacterial endotoxin (LPS). The results showed that TNS dilutions of 1:3, 1:6 and 1:12 cauld induce disappearance of Plasmodium falciparum (P0.05) after being cultured 6 hours. TNS decreased red blood cell infective rate of the parasites as compared with the control (P0.05) after 12 hours' cultivation. TNS of 1:3 dilution had further effect at 24 hours (P0.05). Morphological observations showed that the growth of schizonts was retarded and abnormal merozoites were found.