Expression and characterization of anticoagulant activity of salivary protein alALP from Asian tiger mosquito Aedes albopictus

@#Several bioactive molecules isolated from the saliva of blood-sucking arthropods, such as mosquitoes, have been shown to exhibit potential anticoagulant function. We have previously identified a 30kDa allergen named Aegyptin-like protein (alALP), which is highly homologous to Aegyptin, from the salivary glands of female Aedes albopictus (Asian tiger mosquito). In this study, we identified the conserved functional domain of alALP by using bioinformatic tools, and expressed the His-tagged alALP recombinant protein in sf9 insect cells by generation and transfection of a baculoviral expression plasmid carrying the fulllength cDNA of alALP. We purified this recombinant protein and examined its function on the inhibition of blood coagulation. The results showed that the purified His-alALP prolonged the Activated Partial Thromboplastin Time (APTT), Prothrombin Time (PT) and Thrombin Time (TT) in vitro as well as the Bleeding Time (BT) in vivo, which suggest that alALP could be a novel anticoagulant.

Bimanual irrigation-aspiration for ectopia lentis and use of a small incision for 4-point scleral-sutured foldable intraocular lens and anterior vitrectomy in patients with Marfan syndrome

Purpose: This study evaluated bimanual intracapsular irrigation-aspiration for ectopia lentis with use of a small incision for 4-point scleral fixation of a foldable posterior-chamber intraocular lens (IOL) and anterior vitrectomy in patients with Marfan syndrome. Methods: We performed a retrospective study of 18 eyes from 10 patients with Marfan syndrome who underwent surgical intervention for ectopia lentis at our clinic between July 2012 and September 2018. In this study, intraoperative and postoperative complications, uncorrected visual acuity, best-corrected visual acuity, spherical equivalent, intraocular pressure, and endothelial cell density were evaluated. Results: No intraoperative complications were reported. In all cases, early postoperative evaluation revealed a clear cornea, round pupil, and well-centered IOL. Mean logMAR uncorrected visual acuity improved from 1.09 preoperatively to 0.56 postoperatively (P < 0.05). Mean logMAR best-corrected visual acuity improved from 0.45 preoperatively to 0.17 postoperatively (P < 0.05). Aside from transient ocular hypertension, no postoperative complications were reported. Conclusion: The combined surgical technique presented above yields excellent visual outcomes with an extremely low incidence of complications. This approach is simple, safe, and effective in the treatment of ectopia lentis in patients with Marfan syndrome.

The clinicopathologic and immunohistochemical features of villoglandular adenocarcinoma of uterine cervix

Aim: Villoglandular adenocarcinoma (VGA) of the uterine cervix is a variant of endocervical adenocarcinoma. However, the clinicopathologic and immunohistochemical features of VGA are still unclear. The aim of this study was to investigate the clinicopathologic and immunohistochemical features of VGA. Materials and Methods: A total of 20 VGA patients were identified among 852 patients diagnosed with cervical cancer and enrolled in this study. The immunohistochemical levels of Ki-67, P53, P16, progesterone receptor (PR), carcinoembryonic antigen (CEA), vimentin (Vim), and estrogen receptor (ER) were measured by immunohistochemistry. Results: VGA was prevalent in younger women and presented favorable prognosis. Ki-67, P16, and CEA were highly expressed in VGA tissues, while PR expression was hardly to be detected. The positive rates of Ki-67, CEA, and P16 were 90.0%, 90.0%, and 85.0%, respectively, which were significantly higher compared with PR (5.0%, P < 0.001). In addition, the positive rates of P53, Vim, and ER in VGA tissues were 55.0%, 50.0%, and 40.0%, respectively. However, the expression levels of Ki-67, P53, P16, PR, CEA, Vim, and ER were not significantly associated with clinical features (P > 0.05). Conclusion: These data indicate that VGA is a rare cervical adenocarcinoma, which is prevalent in younger women, and presents favorable prognosis. Detection of Ki-67, P53, P16, PR, CEA, Vim, and ER would be beneficial for the diagnosis of VGA.

Transcriptomic differential lncRNA expression is involved in neuropathic pain in rat dorsal root ganglion after spared sciatic nerve injury

Dorsal root ganglia (DRG) neurons regenerate spontaneously after traumatic or surgical injury. Long noncoding RNAs (lncRNAs) are involved in various biological regulation processes. Conditions of lncRNAs in DRG neuron injury deserve to be further investigated. Transcriptomic analysis was performed by high-throughput Illumina HiSeq2500 sequencing to profile the differential genes in L4-L6 DRGs following rat sciatic nerve tying. A total of 1,228 genes were up-regulated and 1,415 down-regulated. By comparing to rat lncRNA database, 86 known and 26 novel lncRNA genes were found to be differential. The 86 known lncRNA genes modulated 866 target genes subject to gene ontology (GO) and KEGG enrichment analysis. The genes involved in the neurotransmitter status of neurons were downregulated and those involved in a neuronal regeneration were upregulated. Known lncRNA gene rno-Cntnap2 was downregulated. There were 13 credible GO terms for the rno-Cntnap2 gene, which had a putative function in cell component of voltage-gated potassium channel complex on the cell surface for neurites. In 26 novel lncRNA genes, 4 were related to 21 mRNA genes. A novel lncRNA gene AC111653.1 improved rno-Hypm synthesizing huntingtin during sciatic nerve regeneration. Real time qPCR results attested the down-regulation of rno-Cntnap lncRNA gene and the upregulation of AC111653.1 lncRNA gene. A total of 26 novel lncRNAs were found. Known lncRNA gene rno-Cntnap2 and novel lncRNA AC111653.1 were involved in neuropathic pain of DRGs after spared sciatic nerve injury. They contributed to peripheral nerve regeneration via the putative mechanisms.

Exosomes promote cetuximab resistance via the PTEN/Akt pathway in colon cancer cells

Cetuximab is widely used in patients with metastatic colon cancer expressing wildtype KRAS. However, acquired drug resistance limits its clinical efficacy. Exosomes are nanosized vesicles secreted by various cell types. Tumor cell-derived exosomes participate in many biological processes, including tumor invasion, metastasis, and drug resistance. In this study, exosomes derived from cetuximab-resistant RKO colon cancer cells induced cetuximab resistance in cetuximab-sensitive Caco-2 cells. Meanwhile, exosomes from RKO and Caco-2 cells showed different levels of phosphatase and tensin homolog (PTEN) and phosphor-Akt. Furthermore, reduced PTEN and increased phosphorylated Akt levels were found in Caco-2 cells after exposure to RKO cell-derived exosomes. Moreover, an Akt inhibitor prevented RKO cell-derived exosome-induced drug resistance in Caco-2 cells. These findings provide novel evidence that exosomes derived from cetuximab-resistant cells could induce cetuximab resistance in cetuximab-sensitive cells, by downregulating PTEN and increasing phosphorylated Akt levels.

Continuous blood purification treatment for endotoxin-induced acute respiratory distress syndrome

This study aimed to explore the effects of continuous blood purification (CBP) treatment in pigs affected with acute respiratory distress syndrome (ARDS). A total of 12 healthy male pigs, weighing 12±1.8 kg, were randomly and equally assigned to the control and experimental groups. The ARDS pig model was prepared by intravenous injections of endotoxin (20 µg/kg). The control group was given conventional supportive therapy, while the experimental group was given continuous veno-venous hemofiltration therapy. During the treatment process, the variations in dynamic lung compliance, oxygenation index, hemodynamics, and urine volume per hour at different times (Baseline, 0, 2, 4, and 6 h) were recorded. The levels of tumor necrosis factor (TNF-α), interleukin 6 (IL-6), and IL-10 in serum and bronchoalveolar lavage fluid (BALF) were measured using the enzyme-linked immunosorbent assay. The histomorphological changes of the lung, heart, and kidney were visualized using a light microscope. The nuclear factor κB p65 protein content of the heart, lung, and kidney tissues was also detected using western blot. The experimental group outperformed the control group in both respiratory and hemodynamic events. CBP treatment cleared TNF-α, IL-6, and IL-10 partially from serum and BALF. The pathological examination of the heart, lung, and kidney tissues revealed that the injury was less severe in the experimental group. CBP treatment can improve the organ functions of pigs affected with endotoxin-induced ARDS and protect these organs to some extent.

Cardioprotection against experimental myocardial ischemic injury using cornin

Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt.

Quinalizarin, a specific CK2 inhibitor, reduces cell viability and suppresses migration and accelerates apoptosis in different human lung cancer cell lines.

BACKGROUND: Protein kinase CK2 is widely expressed in eukaryotic cells, and plays an important role in cell proliferation, migration, apoptosis, etc. The aim of the current study is to explore how Quinalizarin, a specific CK2 inhibitor, affects the cell proliferation, migration, and apoptosis of different pathological and genetic types of human lung cancer cell lines. MATERIALS AND METHODS: MTT assays were performed to evaluate the cell viability after being treated by Quinalizarin. Transwell migration assays were used to assess whether Quinalizarin could suppress cell migration. Flow cytometry was employed to test the apoptosis rate of different cells. RESULTS: After being treated by Quinalizarin, the viability of different pathological types of lung cancer cells (H446, H460, A549) were significantly suppressed in a time and dose‑dependent manner. More interestingly, in a serial of human lung adenocarcinoma cell lines with different epidermal growth factor receptor (EGFR) mutation status, Quinalizarin was shown to have a much better ability to reduce the viability of cells with EGFR sensitive mutation than those with resistance mutations. Meanwhile, we also found that the cell migration of different pathological types of lung cancer cells (H446, H460, A549) was significantly decreased by Quinalizarin dose‑dependently. In addition, the apoptosis rates in those cells were proved to be increased after exposed to Quinalizarin. CONCLUSIONS: Quinalizarin, the specific CK2 inhibitor, could reduce cell viability with emphasis on adenocarcinoma cells harboring EGFR sensitive mutation, suppresses migration, and accelerates apoptosis in different human lung cancer cell lines.

MFG-E8, a clearance glycoprotein of apoptotic cells, as a new marker of disease severity in chronic obstructive pulmonary disease

Milk fat globule epidermal growth factor 8 (MFG-E8) is an opsonin involved in the phagocytosis of apoptotic cells. In patients with chronic obstructive pulmonary disease (COPD), apoptotic cell clearance is defective. However, whether aberrant MFG-E8 expression is involved in this defect is unknown. In this study, we examined the expression of MFG-E8 in COPD patients. MFG-E8, interleukin (IL)-1β and transforming growth factor (TGF)-β levels were measured in the plasma of 96 COPD patients (93 males, 3 females; age range: 62.12±10.39) and 87 age-matched healthy controls (85 males, 2 females; age range: 64.81±10.11 years) using an enzyme-linked immunosorbent assay. Compared with controls, COPD patients had a significantly lower plasma MFG-E8 levels (P<0.01) and significantly higher plasma TGF-β levels (P=0.002), whereas there was no difference in plasma IL-1β levels between the two groups. Moreover, plasma MFG-E8 levels decreased progressively between Global Initiative for Chronic Obstructive Lung Disease (GOLD) I and GOLD IV stage COPD. Multiple regression analysis showed that the forced expiratory volume in 1 s (FEV1 % predicted) and smoking habit were powerful predictors of MFG-E8 in COPD (P<0.01 and P=0.026, respectively). MFG-E8 was positively associated with the FEV1 % predicted and negatively associated with smoking habit. The area under the receiver operating characteristic curve was 0.874 (95% confidence interval: 0.798-0.95; P<0.01). Our findings demonstrated the utility of MFG-E8 as a marker of disease severity in COPD and that cigarette smoke impaired MFG-E8 expression in these patients.

Evaluation of primary thyroid lymphoma by ultrasonography combined with contrast‑enhanced ultrasonography: A pilot study.

OBJECTIVE: To evaluate the features of primary thyroid lymphoma (PTL) by ultrasonography (US) combined with contrast‑enhanced ultrasonography (CEUS). MATERIALS AND METHODS: In this retrospective study, 20 patients (8 male and 12 female) with PTL were evaluated by conventional US and among them, 10 patients underwent CEUS examination. The appearance of US features was classified into three types: Diffusive mass type, multiple nodular type and mixed type. The CEUS patterns included diffusive homogeneous enhancement and diffusive heterogeneous enhancement pattern. Parameters of CEUS time‑intensive curve were analyzed in primary tumor and involved lymph nodes compared to ipsilateral common carotid artery. RESULTS: Of 20 patients with PTL, 18 presented an enlarging neck mass that grew rapidly with an average duration of 3.2 months, and 17 were associated with Hashimoto’s thyroiditis. In conventional US, all patients had marked hypoechoic masses. Among them, 12 patients were diffusive mass type, 6 were multiple nodular type and 2 were mixed type. For CEUS patterns, 8 were diffusive homogeneous enhancement and 2 were diffusive heterogeneous enhancement. Necrosis areas were showed in diffuse heterogeneous pattern which were hardly seen in conventional US. In the quantitative analysis of CEUS parameters, the time to peak of time‑intensive curve in the primary tumors or involved lymph nodes was longer than that of the ipsilateral common carotid artery (P = 0.004). CONCLUSION: PTL mainly demonstrated as a diffusive mass type with marked hypoechogenecity on conventional US and diffusive homogeneous enhancement pattern on CEUS. And the heterogeneous enhancement pattern is also helpful for detecting necrosis areas of PTL.

Esculetin, a coumarin derivative, exerts in vitro and in vivo antiproliferative activity against hepatocellular carcinoma by initiating a mitochondrial-dependent apoptosis pathway

This study investigated the in vitro and in vivo antiproliferative activity of esculetin against hepatocellular carcinoma, and clarified its potential molecular mechanisms. Cell viability was determined by the MTT (tetrazolium) colorimetric assay. In vivo antitumor activity of esculetin was evaluated in a hepatocellular carcinoma mouse model. Seventy-five C57BL/6J mice were implanted with Hepa1-6 cells and randomized into five groups (n=15 each) given daily intraperitoneal injections of vehicle (physiological saline), esculetin (200, 400, or 700 mg·kg-1·day-1), or 5-Fu (200 mg·kg-1·day-1) for 15 days. Esculetin significantly decreased tumor growth in mice bearing Hepa1-6 cells. Tumor weight was decreased by 20.33, 40.37, and 55.42% with increasing doses of esculetin. Esculetin significantly inhibited proliferation of HCC cells in a concentration- and time-dependent manner and with an IC50 value of 2.24 mM. It blocked the cell cycle at S phase and induced apoptosis in SMMC-7721 cells with significant elevation of caspase-3 and caspase-9 activity, but did not affect caspase-8 activity. Moreover, esculetin treatment resulted in the collapse of mitochondrial membrane potential in vitro and in vivo accompanied by increased Bax expression and decreased Bcl-2 expression at both transcriptional and translational levels. Thus, esculetin exerted in vitro and in vivo antiproliferative activity in hepatocellular carcinoma, and its mechanisms involved initiation of a mitochondrial-mediated, caspase-dependent apoptosis pathway.

Effects of 5-aza-2′deoxycytidine on RECK gene expression and tumor invasion in salivary adenoid cystic carcinoma

Reversion-inducing cysteine-rich protein with kazal motifs (RECK), a novel tumor suppressor gene that negatively regulates matrix metalloproteinases (MMPs), is expressed in various normal human tissues but downregulated in several types of human tumors. The molecular mechanism for this downregulation and its biological significance in salivary adenoid cystic carcinoma (SACC) are unclear. In the present study, we investigated the effects of a DNA methyltransferase (DNMT) inhibitor, 5-aza-2′deoxycytidine (5-aza-dC), on the methylation status of the RECK gene and tumor invasion in SACC cell lines. Methylation-specific PCR (MSP), Western blot analysis, and quantitative real-time PCR were used to investigate the methylation status of the RECK gene and expression of RECK mRNA and protein in SACC cell lines. The invasive ability of SACC cells was examined by the Transwell migration assay. Promoter methylation was only found in the ACC-M cell line. Treatment of ACC-M cells with 5-aza-dC partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression of mRNA and protein, and 5-aza-dC significantly suppressed ACC-M cell invasive ability. Our findings showed that 5-aza-dC inhibited cancer cell invasion through the reversal of RECK gene hypermethylation, which might be a promising chemotherapy approach in SACC treatment.

Evaluation of ultrasound application in diagnosis and clinical staging of thyroid cancers.

Objectives: The usage of Ultrasonography (US) in the diagnosis and management of patients with thyroid nodules and thyroid cancer is increasing. This method is also advocated for the pre-operative and post-operative diagnosis of cervical lymph node (LN) metastases. This article is trying to figure out the correlation between ultrasound features and pathological classification of thyroid carcinoma (TC). Materials and Methods: A total of 407 cases of patients with TC were selected from records between 2000 and 2006, which were used to analyze and compare the ultrasound features in different pathologic classification of TC. We grouped the US typing of TC according to the ultrasound features. Then, we implemented pre-surgery evaluation of TC by ultrasound assessment. Results: We classified these patients into six groups by ultrasound: (1) classical, (2) non-typical, (3) microminiaturize, (4) diffuse sclerosing, (5) medullary, and (6) undifferentiated. Ultrasonographic types of papillary TC: (1) classical, (2) microminiaturize, (3) diffuse, (4) cystic, (5) peripheral, (6) multi-nodules, (7) invasive, and (8) complicated Hashimoto. Grouping of the ultrasonic type of cervical LN metastasis: (1) cystic, (2) micro calcification, (3) macro-lymph, (4) microminiaturize, and (5) invasive. The ultrasound assessment of clinical staging had a higher sensitivity rate and specificity, and the accuracy rate of T stage was 93.9%. Conclusion: Ultrasound is a useful tool in the evaluation, characterization, quantification, and location of TC and cervical LN metastasis.

Expression of beclin 1 in primary salivary adenoid cystic carcinoma and its relation to Bcl-2 and p53 and prognosis

Beclin 1 plays a critical role in autophagy and functions as a haploinsufficient tumor suppressor. The expression and prognostic significance of beclin 1 in head and neck adenoid cystic carcinoma (ACC) are largely unexplored. Therefore, we investigated the expression of beclin 1, Bcl-2, and p53 in head and neck ACC tissue. Tissue samples from 35 cases (15 females, 20 males) of head and neck ACC were utilized for immunohistochemistry. Beclin 1 expression was observed in 32 cases (91.4%) and considered to be high in 15 cases (42.9%) and low in 20 cases (57.1%). Beclin 1 expression was significantly correlated with a histological growth pattern (P=0.046) and histological grade (P=0.037). Beclin 1 expression was inversely correlated with Bcl-2 expression (P=0.013) and significantly associated with overall survival (P=0.006). Bcl-2 and p53 expression were observed in 21 cases (60.0%) and 16 cases (45.7%). Bcl-2 expression was significantly correlated with perineural invasion (P=0.041) and not associated with overall survival (P=0.053). p53 expression was directly correlated with beclin 1 expression (P=0.044). Our results indicated that beclin 1 may be a novel, promising prognostic factor for clinical outcome in head and neck ACC patients and may play a part in the development of head and neck ACC by interacting with Bcl-2 and p53.

Construction of a recombinant plasmid harbouring the glyceraldenyde-3-phosphate dehydrogenase gene of periodic Brugia malayi and observation on DNA immunity.

Purpose: Controlling and eliminating lymphatic filariasis will require further research of preventative measures and implementation. Parasite is dependent on glycolysis for ATP production. The glycolytic enzyme glyceraldenyde-3-phosphate dehydrogenase (GAPDH) plays an important role in glycolysis and therefore is either a potential target for anti-parasite drug development or a vaccine candidate. Therefore, we tried to investigate the DNA vaccine-elicited immune responses in BALB/c mice. Materials and Methods: We cloned a gene encoding the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from periodic Brugia malayi into vector pcDNA3.1. Mice were injected at a dosage of 100 μg recombinant plasmid DNA with CpG intramuscular injection and immunized three times at 2-week intervals. pcDNA3.1 and normal saline were used as control. The tissue of muscles at the 4 weeks after the third injection was collected and target genes were detected using RT-PCR. The humoral responses elicited in mice by inoculation with the recombinant plasmid pcDNA3.1-BmGAPDH were detected using a standard ELISA. Two weeks after the third immunization, stimulation index (SI) was measured using the MTT method and the level of secreted IL-4 and INF-g were detected using ELISA. Results: Specific gene fragment coding GAPDH was amplified and the recombinant plasmid pcDNA3.1-BmGAPDH was constructed. Post-challenge sera from the mice immunized with the DNA vaccine had specific antibody titres of 1:1600 to 1:6400, and the highest titre was observed in the mice that were inoculated by pcDNA3.1-BmGAPDH/CpG at 6 weeks. At 4 weeks after immunization, the spleens of the mice were obviously enlarged. The proliferation of spleen T lymphocytes seen on the MTT assay was higher in the pcDNA3.1-BmGAPDH group than in the control group (P value <0.05). The levels of IL-4 and INF-g in serums from the immunized mice were significantly higher than that of the control (P value <0.05). Conclusions: We conclude that the recombinant eukaryotic plasmid pcDNA3.1-BmGAPDH could elicit humoral and cellular immune responses in mice.

An effective indirect fluorescent antibody test for diagnosis of intestinal acariasis.

Adult mites' bodies of Dermatophagoides farinae were used as antigen in an indirect fluorescent antibody test (IFAT) to detect mite-specific IgG in sera of 48 patients with intestinal acariasis based on stool examination. Antibody titers with positive reaction ranged from 1:4 to 1:512 in 48 patients with intestinal acariasis. If antibody titers > or = 1:16 is regarded as being positive, the positive rate of patients detected with IFAT was 92%.

Production of interspecies chimeras by transplanting rosy barb (Puntius conchonius) embryonic cells to zebrafish (Danio rerio) embryos.

Establishment of a cell-mediated gene transfer system has potential as a new breeding technique for commercially valuable fishes. As an important step toward developing an inter-species chimera, cells from blastula-stage embryos of rosy barb (Puntius conchonius) were transplanted into zebrafish (Danio rerio) blastula-stage embryos to observe the development of the recipient. From the total of 473 transplants obtained only a fraction of 13 chimeras appeared perfectly normal after one month. Over two in normal 13 chimeras showed some characters from the donor cells with scarce pigmentation. This is the first successful inter-species study on zebrafish by using blastula cell transplants from rosy barb both belonging to the same family cyprinidae.

Emprego do propofol, isofluorano e morfina para a anestesia geral de longa duraçäo em bezerros / Use of propofol, isoflurane and morphine for prolonged general anesthesia in calves

Foram estudadas características da bioquímica do sangue, da pressäo arterial e da freqüência de pulso de 12 bezerros mantidos sob anestesia por 13 horas, utilizando-se propofol para a induçäo e isofluorano para manutençäo, associados à administraçäo de morfina intra-tecal. Os valores de freqüência de pulso, pressäo arterial e glicemia apresentaram pequenas variaçöes e se mantiveram próximos dos valores de referência para bezerros anestesiados. Ao longo do período de anestesia houve aumento significativo, mas discreto, do hematócrito, hemoglobina, pCO2, CO2 total, bicarbonato e potássio. O pH do sangue, pO2, Na+ e Ca++ apresentaram reduçöes significativas. Este protocolo anestésico foi seguro para a manutençäo de bezerros anestesiados por período prolongado.

Special features of acute infection due to Schistosoma japonicum in urban and rural areas in China.

The statistical analysis of six indices: sex, age, occupation, time of onset, mode of infection and educational level of acute cases infected by Schistosoma japonicum in 1990 and 1994 respectively in Wuhu city was carried out. No significant differences were found in the five indices between 1990 and 1994 in Wuhu city except sex. There were significant differences between the urban and rural areas in all six indices.

Isotypic antibody responses of a population in an endemic area of schistosomiasis japonica and their epidemiologic significance.

The present study was designed to explore if there exists a correlation between predominant isotype-defined antibody levels and reinfection in low age groups of the population in an endemic area of schistosomiasis japonica in China. One hundred and thirty-eight individuals aged 3-25 years old were selected for serological investigations including the levels of IgG, IgG4, IgM and IgE, detected by ELISA with soluble egg antigen and soluble adult worm antigen. Results show that age is a determinant for SEA-specific IgG, IgG4, and IgE, and SWA-specific IgG and IgG4 antibody levels, which increased with age, and that SEA- and SWA- specific IgG4 antibody levels are risk factors of reinfection, ie, the risk of reinfection occurrence of the population with high level of SEA or SWA-specific IgG4 is 2.83 or 2.40 times, respectively, that with low level of SEA or SWA-specific IgG4, suggesting that in the endemic area of schistosomiasis japonica, there exists a possibility that in the population aged 3-25 years, SEA and SWA-specific IgG4 antibodies mediate a blocking immunity response.