[Analysis of polymorphism on ribosomal internal transcribed spacer 2 in four species of sandflies with PCR-RFLP].

Internal transcribed spacer 2 region in 4 species of sandflies from China (Phlebotomus chinensis, Ph. wui, Ph. longiductus and Ph. alexandri) was genotyped by PCR-RFLP. Four kinds of RFLP band patterns were created by Dra I, that were A 450 bp, B 154 bp/127 bp/93 bp/66 bp/10 hp, C 311 bp/80 bp/60 bp, and D 353 bp/300 bp/160 bp/58 bp. There were identical pattern types in various sandflies, AA in Ph. chinensis, BB in Ph. alexandri, CC in Ph. wui, and DD in Ph. longiductus. The results indicated that PCR-RFLP can be used to identify the four species of Phlebotomus in China.

[Investigation on transmitting vectors of visceral leishmaniasis in Jiashi County, Xinjiang].

OBJECTIVE: To investigate sandfly vectors transmitting visceral leishmaniasis, including species and seasonal distribution in Jiashi county of Xinjiang Uygur Autonomous Region. METHODS: Sandflies were collected in the field, counted and identified. The specimens were dissected to analyze the gonotrophic cycle and to find infection of promastigotes. The resting places were observed by using oil-paper and sandfly-capturing trap. RESULTS: 4540 sandflies were collected with 99.9% of Phlebotomus wui and only 0.1% Sergentomyia minutus sinkiangensis. On the seasonal distribution, the first peak appeared by the end of May and the first ten-day of June, and the second peak was in the middle of August. Observation showed that the activity of sandflies occurred mainly from 22:00 to 4:00, reaching to the maximum in the midnight. Analysis on the gonotrophic cycle revealed that Ph. wui was an exophilic species and appeared nocturnally for feeding with preference to human blood. Natural infection with promastigotes was found in 4 sandflies, more in the field than the residential area. Resting places included the aperture on the wall of livestock sheds and in the caves. CONCLUSION: Ph. wui is the predominant species in Jiashi, with higher infection rate of natural promastigotes in the field and with two life generations annually.

[An epidemiological survey of visceral leishmaniasis in Hamangou coal mine area of Korla City, Xinjiang].

OBJECTIVE: To investigate the epidemiological status of visceral leishmaniasis in Hamangou coal mine area of Korla City of Xinjiang Uygur Autonomous Region. METHODS: Based on a hint of possible existence of patients, a retrospective survey was carried out house by house to find cases with suspected signs/symptoms of the disease. Meanwhile, a survey on current status was conducted, including physical examination (liver and spleen palpation) to those less than 15 years-old, leishmanin skin test and rk39 immunochromatographic strip test for part of the residents. Bone marrow smears were examined for the cases with clinical signs/symptoms and positive rk39 strip test. Sandflies were collected using routine methods in and around the area, identified, and dissected to find infection of promastigotes. RESULTS: Leishmanin skin test was performed in 185 people with a positive rate of 21.1% (39/185), 39 out of 140 local residents who have lived there for more than 6 years showed positive (27.9%), while all residents who have lived less than 6 years and children under 5 years old were negative. Of the 81 children under 15 years old with a negative skin test, one showed positive for rk39 strip test, and leishmania body was found in the bone marrow smear of this case, so confirmed as visceral leishmaniasis. 12 sandflies were identified as Phlebotomus alexandri, and natural infection with promastigotes was found in one sandly. CONCLUSION: The investigation confirms that visceral leishmaniasis is endemic in the Hamangou coal mine area.

[Field test of sandfly-catching by light traps and attractants].

Three kinds of light traps, attractants and their combination were used to collect sandflies in Andier township, Minfeng County of Xinjiang. The combined use of carbon dioxide and tungsten lamp showed better attraction effect to sandflies, also an easier way for the separation of insects collected.

[A newly identified endemic area of visceral leishmaniasis in Minfeng county of South Xinjiang I. epidemiological survey].

OBJECTIVE: To investigate the epidemiological status of visceral leishmaniasis in Minfeng county, a newly identified endemic area in south Xinjiang, China. METHODS: Based on a hint of possible existence of patients, a retrospective survey was carried out house by house in Andier Township of the county to find cases with suspected signs/symptoms of the disease in the past 20 years including those died. Meanwhile, a survey on current status was conducted, including physical examination(liver and spleen palpation) to those under 15 years-old, leishmanin skin test and rk39 immunochromatographic strip test for part of the residents. RESULTS: The investigation covered 313 local residents and revealed no case with present illness but 60 cases with a history of suspected signs/symptoms including 13 deaths, traced back as visceral leishmaniasis. Leishmanin skin test was performed in 171 people with a positive rate of 99.4% and 28 out of 29 suspected cases showed positive (96.6%). rk39 immunochromatographic strip test was conducted in 197 people with a positive rate of 10.2% (20/197) and 19.4% (6/31) in those with a history of suspected signs/symptoms. CONCLUSION: The epidemiological investigation indicates that the Andier Township of Minfeng County is an endemic area of visceral leishmaniasis.

[A newly identified endemic area of visceral leishmaniasis in Minfeng county of south Xinjiang II. Investigation on phlebotomine vectors].

OBJECTIVE: To investigate the transmitting phlebotomine sandfly in Minfeng County, a newly-identified endemic area of visceral leishmaniasis in the south of Talim Pendi of Xinjiang. METHODS: Sandflies were collected using routine methods in and around the Yatonggusi village of Andier Township. The sandflies were identified to get their composition. Sandfly density was calculated following an observation at a given spot and time-period, and their appearance was recorded at night-time and day-time. Sandflies were dissected to analyze the gonotrophic cycle and to find infection of promastigotes. RESULTS: Phlebotomus wui was identified as the transmitting vector of visceral leishmaniasis in Andier Township, which occupied 99.2% of the sandflies collected. The first and second ten-day period of June was the first peak of its seasonal distribution. Analysis of the gonotrophic cycle revealed that Ph. wui was an exophilic species and appeared nocturnally for feeding with preference to human blood. Natural infection with promastigotes was found in 2 sandflies. CONCLUSION: Phlebotomus wui is the transmitting vector for visceral leishmaniasis in the newly found endemic area of south Xinjiang.

[Preliminary test of phlebotomus surveillance by light-traps].

Different light-traps were tested in Wenxian of Gansu Province, including the light-traps without lamp and with glucose solution as attractant. Results showed that the light-traps attracted more mosquitoes and other insects than sandflies, and it became difficult to pick up the sandflies from gathering packet; the light-trap without lamp captured smaller amount of sandflies but much less other insects; glucose showed no significant effect in attracting sandflies. The existing light-traps are not so effective for Phlebotomus surveillance, and it is suggested that more effective attractants be tried.

[Expression deficiency of JWA enhanced DNA damage and delayed DNA repair in HeLa cells induced by benzo (a) pyrene exposure].

OBJECTIVE: To investigate the role of JWA gene in benzo (a) pyrene [B (a) P] induced DNA damage and repair effects in HeLa cells. METHODS: The antisense JWA express vector (pEGFP-C1-asJWA) was constructed and stably transfected into HeLa cells. JWA deficient HeLa cells (asJWA-HeLa) was then screened and established. The general characteristics of asJWA-HeLa cells were investigated. DNA damage and repair cell culture model was conducted by treating the cells with 50 micromol/L B (a) P plus S9 for 3 hours and then the cells were maintained further 0, 1, 3, and 24 hours for DNA repairing. The damaged DNA was detected by single cell gel electrophoresis assay (comet assay). RESULTS: JWA deficient HeLa cells (with a 31% of JWA protein expression as compared with the control) were obtained successfully. Compared with the empty vector transfected cells (C1-HeLa) and the untransfected HeLa cells, asJWA-HeLa cells were more sensitive to B (a) P exposure and with a delayed DNA repair process. CONCLUSION: The JWA determined might function as a potential effective environmental responsive gene and actively participate the process of B (a) P exposure associated with intracellular signal pathways of DNA damage and repair.

[Expression of novel environmental responsive protein JWA involved in the oxidative stress responsiveness in MCF-7 cells].

OBJECTIVE: To study the expression and the possible role of JWA protein in oxidative stress-induced damage of MCF-7 cells, especially the relationship between JWA and heat shock proteins (HSPs). METHODS: MCF-7 cells were exposed to different concentration of H(2)O(2) (0.01,0.10, 1.00 mmol/L) for different time (10, 30, 60 and 180 min) respectively. DNA damage was detected by using DNA gel electrophoresis. The MTT assay was used to analyze the effect of H(2)O(2) on the cytotoxicity and relative cell proliferation ratio of the cells. The expressions of JWA, HSP70, HSP27 and HSF1 were determined by Western-blot. RESULTS: The inhibitory effect on MCF-7 cells viability induced by H(2)O(2) was shown a dose-and time-dependent manner and MCF-7 cells proliferation, and was almost completely inhibited by the exposure of H(2)O(2) at 1.00 mmol/L for 180 min. Hydrogen peroxide treatment of MCF-7 cells caused oxidative stress which up-regulated the expressions of JWA, HSP70 and heat shock factor 1 (HSF1) in a dose-dependent manner, and the expression pattern of JWA was very similar to those of HSP70 and HSF1 but not to HSP27. CONCLUSION: JWA might enhance intracellular defenses against H(2)O(2)-induced oxidative damage in human breast carcinoma cells. JWA is determined functioning as an effective environmental responsive protein and as a parallel molecule of HSP70 actively participates in the signal pathways of oxidative damage which might be regulated by HSF1.

[Relationship between JWA expression and DNA damage-repair in human embryonic lung cells by benzo(a) pyrene].

OBJECTIVE: To investigate the expressions of JWA gene and heat shock protein 70 (hsp70) in human embryonic lung (cccHPF-1) cells after exposure to activated benzo(a)pyrene (B(a)P), and to explore the role and the possible mechanism of JWA gene involved in B(a)P-induced DNA damage and repair. METHODS: The models of DNA damage of ccc-HPF-1 cells were established by treatment of cells with B(a)P plus S9 at 10 to 100 micromol/L for 3 hours with or without 24 hours recovery for DNA repairing. The DNA damage was detected by single cell gel electrophoresis (SCGE) assay (comet assay). And the immuno-blotting assay was used for detecting expressions of JWA and hsp70. RESULTS: JWA expression was actively modulated by B(a)P exposure. The expressions of both JWA and hsp70 were increased greatly at 50 micromol/L and 100 micromol/L B(a)P treated cells and maintained at over expressed levels treated by 10-100 micromol/L B(a)P during the restored time. In addition, JWA expression pattern was similar to that of hsp70. CONCLUSION: JWA is determined in this study by its functioning as an effective environmental responsive gene and actively participating in the signal pathways of DNA damage and repair which might be associated with excision repair.