IgE antibody responses in cerebrospinal fluids relate to the brain pathologic injury of hosts with Angiostrongylus cantonensis infection.

BACKGROUND: The immunoglobulin E (IgE) response to Angiostrongylus cantonensis infection increases in the host. This study analyzed the IgG and IgE responses detected in different body fluids of A. cantonensis-infected mice. METHODS: BALB/c (high susceptibility), CBA (medium), and C57BL/6 and C57BL/10 (resistance) strain mice were used in this study. The levels of IgM, IgG, and IgE in the serum and cerebrospinal fluid (CSF) from infected mice were compared. A. cantonensis-reactive antigens from BALB/c and C57BL/6 mice CSF were also analyzed. RESULTS: Antibodies against fifth-stage larvae (L5) antigens increased in mice CSF, particularly IgE, relate to worm rejection and the susceptibility of different mouse strains. The increased IgE level in BALB/c mice CSF is lower than that from others, suggesting IgE response in brain is more important than that in serum. Anti-L5 and anti-excretory/secretory (ES) antigen IgE and IgG responses in CSF were analyzed. In addition, the antibody-dependent eosinophil-mediated cytotoxicity induced by anti-excretory/secretory (ES) antigen antibodies may be the reason of severe brain inflammation in infected BALB/c mice. IgE and IgG antibodies against a 105 kDa protein of L5 antigen was detected at week 3 post-infection in C57BL/6 mice and week 5 post-infection in BALB/c mice. We suggest that 105 kDa protein is related with the antibody response of A. cantonensis-infected mice. CONCLUSION: We found that IgE antibodies in mice CSF against L5 antigens related to worm rejection in mice brains. This study may help to identify specific angiostrongyliasis markers that can be applied for clinical diagnosis and treatment in future.

Epidemiologic Investigation of Intestinal Parasite Infection and Associated Risk Factors among Primary Schoolchildren in the Manzini and Lubombo Provinces, the Kingdom of Eswatini.

Although the deworming program has been executed since 2000, the intestinal parasitic infection (IPI) rates among primary schoolchildren (PSC) in the two provinces of the Kingdom of Eswatini investigated in 2010 remained high, reaching 32.2%. In this study, we monitored the IPI status along with the associated risk factors for PSC in two provinces-Manzini and Lubombo. After consent from their parents/guardians, a total of 316 samples collected from PSC with grades 1 to 3 from four primary schools in Manzini and Lubombo were examined by the Merthiolate-Iodine-Formaldehyde (MIF) method. In addition, demographic characteristics and risk factors acquired by questionnaire surveys were included to be statistically analyzed. The overall prevalence was 40.5% (128/316), of which the infection rate in Manzini and Lubombo was 28.8% (19/66) and 58.3% (74/140), respectively. Pathogenic protozoa had the highest infection rate of 20.6% (65/316), including Entamoeba histolytica/dispar (8.5%, 27/316), Giardia duodenalis (14.6%, 46/316), and Blastocystis hominis (9.8%, 31/316). In terms of helminth infection, the infection rate was quite low, 1.6% only, and these five infected cases included four cases of Hymenolepis nana and one case of Enterobius vermicularis infection. Present study showed that 27.8% (88/316) of PSC were infected by more than one pathogenic parasite. Personal hygiene like washing hands before a meal has a significant protection effect (OR = 0.32, 95% CI = 0.14-0.75, p=0.009). Rain or well water and the type of water supply from which they drank also showed a considerable risk factor (OR = 2.44, 95% CI = 1.25-4.79, p=0.04). The IPI rate in PSC seems unlikely changed compared to that of the previous survey conducted in 2010, especially when the pathogenic protozoan infection rate remains high. Treatment of infected PSC with appropriate medication to reduce intestinal pathogenic protozoan infection should be seriously considered by Eswatini Health Authority.

Percutaneous radiofrequency trigeminal rhizotomy benefits in patients with refractory trigeminal neuralgia.

ABSTRACT: A significant number of patients suffers from refractory trigeminal neuralgia (TN) after receiving microvascular decompression (MVD) or other neuro-destructive procedure such as gamma knife radiosurgery (GKRS). This study aims to demonstrate a remediable, reproducible approach to treating refractory pain effectively by percutaneous radiofrequency trigeminal rhizotomy (RF-TR).A total of 392 patients with TN were treated by RF-TR during the past 10 years. Among these patients, 48 cases who had received either MVD, GKRS alone, or a combination of both were assigned to group A. Those who had not received any form of treatment (125 patients) or failed to respond medically (130 patients) were assigned as the control group (group B). All the RF-TR were performed by a single surgeon with the aid of intraoperative computed tomography (iCT)-based neuronavigation with magnetic resonance (MR) image fusion. The outcome measure was the numerical rating scale (NRS) expressed subjectively by patients. The paired Student t test and the analysis of covariance (ANCOVA) were used for statistical analysis.In group A, 21 of 24 patients (88%) had significant improvement (NRS change ≥5) in facial pain after RF-TR. The average NRS score was 9.75 ±â€Š0.53 before the procedure and 1.92 ±â€Š3.35 post-treatment (significant NRS decrease [P = .000]). On the other hand, in group B, 226 of 255 patients (89%) also had dramatic amelioration of facial pain after RF-TR. The average NRS score was 9.46 ±â€Š0.69 before the procedure and 1.62 ±â€Š2.85 post-treatment (7.84 ±â€Š2.82 in NRS decrease [P = .008]). By using a univariate ANCOVA, no statistical significance was found in NRS score improvement between the two groups.Repeated MVD and GKRS for refractory TN may be less desirable due to a greater risk of mortality (up to 0.8%) and morbidity (4% of serious complications). Conversely, RF-TR administration with the novel navigation technique by using iCT and MR image fusion is free from any remarkable and irreversible morbidities. In this study, RF-TR not only provided an alternative and effective strategy if TN recurred but also resulted in the same NRS score improvement regardless of the status of prior treatment.

Prevalence of Pediculus capitis in schoolchildren in Battambang, Cambodia.

BACKGROUND/PURPOSE: Pediculus capitis is the most common human ectoparasite. When it feeds on the blood through the scalp of its host, the anticoagulant in its saliva causes scalp inflammation and itching, and consequent scratching by the host causes further inflammation from bacterial infection. P. capitis infestation is currently a common parasitic dermatosis and a critical public health concern in underdeveloped countries. METHODS: Through naked eye inspection of P. capitis on or in the hair from 323 school children in Cambodia. RESULTS: A total of 143 children (44.3%) were found to have P. capitis infestation. Univariate analysis revealed that girls had a significantly higher infection rate than boys. Overall, young aged schoolchildren (10 yrs old ≤) showed significantly higher infection rate than old aged schoolchildren (>10 yrs old). Groups stratified by time revealed that schoolchildren studied at the afternoon classes than morning classes in Tuol Prum Muoy Primary School had a significantly higher risk in acquisition of P. capitis infestation. Multivariate analysis results indicated that relative to the boys, the girls were at a significantly higher risk of contracting P. capitis infection. When stratified by inspection time with the Tuol Prum Muoy Primary School morning classes as the reference, the Tuol Prum Muoy Primary School afternoon classes exhibited a significantly higher risk of P. capitis infection. CONCLUSION: Primary school children in Cambodia have a high P. capitis infection rate and thus require effective treatment and prevention measures to treat symptoms and lower the infection rate.

Intestinal parasitic infections: Current status and associated risk factors among school aged children in an archetypal African urban slum in Nigeria.

BACKGROUND/PURPOSE: Intestinal parasitic infections (IPIs) among school aged children (SAC) in Nigeria remains endemic, hence the need for regular surveillance to attract the attention of policy makers. This cross-sectional study investigated the current prevalence and factors associated with intestinal parasitic infections among school aged children in an urban slum of Lagos City, Nigeria. METHODS: Single stool samples from 384 school aged children (188 boys and 196 girls) were examined by employing Merthiolate-iodine-formaldehyde concentration (MIFC) and Kato-Katz methods. Demographic characteristics and risk factors were obtained by questionnaires investigation. RESULTS: The overall prevalence was 86.2% in school children, out of them 39.1% had polyparasitism. IPIs showed the highest to the lowest prevalence of 62% (238/384), 25% (97/384), 12.3% (47/384), 11.8% (45/384), 9.9% (38/384), 8.4% (32/384), 3.4% (13/384), and 0.5% (2/384) found in Ascaris lumbricoides, Entamoeba histolytica/dispar, Giardia duodenalis, Endolimax nana, Entamoeba coli, Trichuris trichiura, Blastocystis hominis, and hookworm infections, respectively. MIFC technique showed superiority to Kato-Katz technique in the detection of IPIs (p < 0.0001). Drinking untreated water was a significant risk factor for these school aged children in acquiring protozoan infections after multivariate adjustment (OR = 1.86, 95% CI = 1.08-3.20, p = 0.02). CONCLUSION: Intestinal parasitic infections are very severe among school aged children in the urban slums, thus regular mass de-worming programs, health education, and the provision of safe drinking water is recommended to combat IPIs among the school aged children.

Enhanced expressions of neurodegeneration-associated factors, UPS impairment, and excess Aß accumulation in the hippocampus of mice with persistent cerebral toxocariasis.

BACKGROUND: Toxocariasis is a worldwide zoonotic parasitic disease mainly caused by Toxocara canis. Humans can be infected by accidental ingestion of T. canis embryonated ovum-contaminated food, water, or encapsulated larvae in paratenic hosts' viscera or meat. Since humans and mice are paratenic hosts of T. canis, the wandering larvae might cause mechanical tissue damage and excretory-secretory antigens may trigger inflammatory injuries to local organs. Long-term residence of T. canis larvae in a paratenic host's brain may cause cerebral toxocariasis (CT) that contributes to cerebral damage, neuroinflammation and neuropsychiatric disorders in mice and clinical patients. Since the hippocampus has been long recognized as being responsible for learning and memory functions, parasitic invasion of this site may cause neuroinflammatory and neurodegenerative disorders. The present study intended to assess pathological changes, expressions of neurodegeneration-associated factors (NDAFs), including transforming growth factor (TGF)-ß1, S100B, glial fibrillary acidic protein (GFAP), transglutaminase type 2 (TG2), claudin-5, substance P (SP) and interleukin (IL)-1ß, and the ubiquitin-proteasome system (UPS) function in the hippocampus and associated cognitive behavior in ICR mice orally inoculated with a high, medium or low-dose of T. canis embryonated ova during a 20-week investigation. RESULTS: Results indicated although there were insignificant differences in learning and memory function between the experimental mice and uninfected control mice, possibly because the site where T. canis larvae invaded was the surrounding area but not the hippocampus per se. Nevertheless, enhanced expressions of NDAF, persistent UPS impairment and excess amyloid ß (Aß) accumulation concomitantly emerged in the experimental mice hippocampus at 8, 16 and 20 weeks post-infection. CONCLUSIONS: We thus postulate that progressive CT may still progress to neurodegeneration due to enhanced NDAF expressions, persistent UPS impairment and excess Aß accumulation in the hippocampus.

Intestinal parasitic infections: Current prevalence and risk factors among schoolchildren in capital area of the Republic of Marshall Islands.

Intestinal parasitic infections (IPIs) among schoolchildren in Republic of Marshall Islands (RMI) largely remains unknown, thus investigation on IPIs status to establish the baseline data is urgently needed. This cross-sectional study intended to investigate the current IPIs status and associated risk factors among schoolchildren at capital of RMI. Single stool sample from 400 schoolchildren (207 boys and 193 girls) aged 9.73±2.50 yrs old was examined by employing merthiolate-iodine-formaldehyde concentration method. Demographic characteristics, uncomfortable symptoms and risk factors were obtained by questionnaires investigation. The overall prevalence of IPIs in schoolchildren was 22.8% (91/400), of them 24.2% harbored at least 2 different parasites. Notably, the majority was infected by waterborne protozoan parasites (82.4%, 75/91). Nine different intestinal parasites have been identified, of which six were pathogenic including Hook worm, Trichuris trichiura, Enterobius vermicularis, Entamoeba histolytica/dispar, Giardia intestinalis and Blastocystis hominis. Schoolchildren who ever complained dizziness or headache showed a significant higher prevalence of pathogenic IPIs than those who did not (p<0.05). Schoolchildren who lived in urban area than rural area had higher chance to acquire pathogenic IPIs (p=0.03). However, none of risk factors were identified to be associated with pathogenic IPIs.

Prevalence and Risk Factors for Intestinal Parasitic Infection in Schoolchildren in Battambang, Cambodia.

Most intestinal parasitic infections (IPIs), commonly endemic in tropical resource-poor developing countries, are neglected tropical diseases. Parasitic infections and malnutrition are most commonly found in children. We determined the prevalence of IPIs and the risk factors in Battambang Province, northwestern Cambodia, from August to September 2015. This study collected 308 valid questionnaires and specimens from Dontri (173, 56.2%) and Kon Kaêk (135, 43.8%) primary schools. All stool samples were examined using Chang's Feces Examination Apparatus through the merthiolate-iodine-formaldehyde technique. Headache (259, 84.1%), recurrent cough (249, 80.8%), and abdominal pain (235, 76.3%) were the most common symptoms as detected from questionnaire investigation. A total of 155 students were positive for any parasite type; a single parasite type was observed in 97 students (31.5%), two types in 40 students (13.0%), three types in 14 students (4.6%), and four types in four students (1.3%). Nine gastrointestinal parasite species (three helminths and six protozoa) were identified in the stool samples. The most common parasites in schoolchildren were Giardia intestinalis (31.5%) and Entamoeba histolytica/dispar (17.5%). This is the first IPIs study, and more than half of the schoolchildren were infected with parasite species in Moung Russey District of Battambang Province. We found nine parasite species, including helminths and protozoa, and pathogenic protozoa were the main source of IPIs. Improving the detection method, sanitation facilities, and personal hygiene as well as utilizing combined drugs are all important measures to greatly reduce IPIs in Cambodian schoolchildren.

Knowledge of human social and behavioral factors essential for the success of community malaria control intervention programs: The case of Lomahasha in Swaziland.

BACKGROUND: Although malaria control programs have made rapid progress recently, they neglect important social and behavioral factors associated with the disease. Social, political, and cultural factors are involved in malaria control, and individuals in a community may be comfortable in behaving in ways that, to an outsider, may seem contrary to commonly held perceptions. Malaria control efforts can no longer afford to overlook the multidimensional human contexts that create and support varying notions of malaria and its prevention, treatment, and control. This study aimed to assess the knowledge and perceptions of malaria issues in the community, and to identify practices that support or hinder the progress of malaria control programs. METHODS: A triangulation study involving individual interviews, focus group discussions, and observatory analysis between 2003 and 2010 at Lomahasha, a malarious community on the eastern border of Swaziland and Mozambique, was conducted. RESULTS: Results indicated that a high knowledge level and good perception of the disease were observed in the age group of < 40 years, contrary to those in higher age groups, among the Lomahasha community members. However, behavior of certain community groups includes practices that are not supportive of the national control program's aspirations, such as delay in seeking medical attention, staying outdoors until late, maintaining stagnant water in roadside excavations, and seeking medical assistance from wrong sources. Malpractices are more commonly observed among men, boys, and those who drink alcohol. CONCLUSION: This study suggests a thorough community diagnosis before all intervention programs for malaria control are instituted.

Prevalence of intestinal parasitic infections among school children in capital areas of the Democratic Republic of São Tomé and Príncipe, West Africa.

BACKGROUND: Although the Democratic Republic of Sao Tome and Principe (DRSTP) has undertaken school children-based deworming programs against intestinal parasitic infections (IPIs) using a single dose of mebendazole annually since 2005, it remains unclear as to the outcome to date. The present study intends to investigate the recent IPIs status among school children living in capital areas of the DRSTP. METHODS: A total of 252 school children (121 boys and 131 girls) of grades 4 and 5 from 4 primary schools located in the capital areas participated in the present study and their fresh fecal specimens were examined for the presence of any parasites using the merthiolate-iodine-formaldehyde concentration method as conducted. RESULTS: The overall prevalence of IPIs was 64.7% (163/ 252). No significant gender difference in prevalence between boys (67.8%) and girls (61.8%) was found (p = 0.3). The majority of school children were infected with a single species of parasite (55.8%). Altogether, 12 different intestinal parasite species were identified in DRSTP school children, of which 9 species were pathogenic and the remaining 3 were non-pathogenic. CONCLUSION: Improving the detection method, sanitation facilities and personal hygiene as well as utilizing combined drugs are all important measures to greatly reduce IPIs in DRSTP school children.

Seroprevalence and Associated Risk Factors of Toxocariasis among College Students in Taipei City, Taiwan.

BACKGROUND: Infection by Toxocara spp. is known to be significantly associated with partial epilepsy. It has become popular for people to raise dogs/cats as pets and consume roasted meat/viscera, and the status of Toxocara spp. infection, epilepsy awareness, and associated risk factors among the general population are currently unknown in Taiwan. METHODS: A seroepidemiological investigation among 203 college students (CSs), consisting of 110 males and 93 females with an average age of 21.5 ± 1.2 years, was conducted in 2009 in Taipei City. A Western blot analysis based on excretory-secretory antigens derived from Toxocara canis larvae (TcESs) was applied to determine the positivity of serum immunoglobulin G antibodies. A self-administered questionnaire was also given to obtain information about demographic characteristics, epilepsy awareness, and risk factors. A logistic regression model was applied for the statistical analysis using SPSS software. RESULTS: The overall seropositive rate of Toxocara spp. infection was 8.4% (17/203). As to epilepsy awareness, a non-significantly higher seroprevalence was found in CSs who claimed to "know" about epilepsy compared to those who did not know (P > 0.05). CONCLUSIONS: It appears that appropriate educational programs are urgently needed to provide correct knowledge related to the prevention and control measures against Toxocara spp. infections to avoid potential threats by this parasite to the general population in Taiwan.

Toxoplasma gondii infection: seroprevalence and associated risk factors among primary schoolchildren in Lagos City, Southern Nigeria.

INTRODUCTION: Toxoplasma gondii infection has been described as the most widespread zoonotic infection of humans and other animals. Information concerning T. gondii infection among schoolchildren is unavailable in Lagos City, Nigeria. METHODS: This cross-sectional study investigated the seroprevalence and risk factors associated with T. gondii infection among primary schoolchildren (PSC) from a community located in the center of Lagos, southern Nigeria, from November 2013 to March 2014. A total of 382 PSC were screened for the presence of sera anti-T. gondii antibodies using a latex agglutination test (TOXO Test-MT, Tokyo, Japan). A cutoff titer of ≥ 1:32 was considered positive, while titers ≥ 1:1,024 indicated high responders. Questionnaires were also used to obtain data on possible risk factors from parents/guardians. RESULTS: The overall seroprevalence was 24% (91/382), and 83.5% (76/91) of seropositive PSC were classified as high responders. Among the risk factors tested, including contact with cats and soil, consumption of raw meat and vegetables, and drinking unboiled water, none showed statistical significance after multivariate adjustment. No associations were observed among age, gender, body mass index (BMI), and parents' occupation/educational level. CONCLUSIONS: The findings in this study show evidence of active infection, and hence, there is need for urgent preventive measures in this city. Further investigation is required to clarify the transmission routes. Policy makers also need to initiate prevention and control programs to protect pregnant women and immunocompromised patients in particular because they are more severely affected by T. gondii infection.

Beneficial effects of co-treatment with dextromethorphan on prenatally methadone-exposed offspring.

BACKGROUND: Heroin use among young women of reproductive age has drawn much attention around the world. Although methadone is widely used in maintenance therapy for heroin/morphine addiction, the long-term effects of prenatal exposure to methadone and preventative therapy remain unclear. For revealing this question, female pregnant Sprague-Dawley rats were sub-grouped to receive (1) vehicle, (2) methadone 5 mg/kg at embryonic day 3 (E3) and then 7 mg/kg from E4 to E20, (3) dextromethorphan (DM) 3 mg/kg, and (4) methadone + DM (the rats received methadone followed by DM treatment), subcutaneously, twice a day from E3 to E20. The body weight, natural withdrawal, pain sensitivity, ED50, conditioned place preference and water maze were conducted at different postnatal stages (P1 to P79) of offspring. The quantitative real-time RT-PCR and electrophysiology were also used to measure the gene expression of opioid receptors in the spinal cord and changes of LTP/LTD in the hippocampus, separately. RESULTS: Prenatal exposure to methadone or DM did not affect survival rate, body weight, water maze and LTP or LTD of offspring. However, prenatal methadone significantly increased the withdrawal symptoms, pain sensitivity, addiction liability and decreased the mRNA expression of pain related opioid receptors. Co-administration of DM with methadone in the maternal rats effectively prevented these abnormalities of offspring induced by methadone. CONCLUSIONS: Our study clearly showed that co-administration of dextromethorphan with methadone in the maternal rats prevented the adverse effects induced by prenatal methadone exposure. It implies that dextromethorphan may have a potential to be used in combination with methadone for maintenance treatment in pregnant heroin-addicted women to prevent the adverse effects induced by methadone on offspring.

Seroprevalence, disease awareness, and risk factors for Toxocara canis infection among primary schoolchildren in Makoko, an urban slum community in Nigeria.

In this study, we investigated the seroprevalence of Toxocara canis infection in southern Nigeria, which previously was unknown, in addition to evaluating disease awareness and potential risk factors for schoolchildren in an urban slum community. In total, 366 primary schoolchildren were investigated for the presence of anti-Toxocara IgG antibodies. Blood was collected and screened by a Western blot analysis based on the excretory-secretory antigens of larval T. canis (TcES), targeting low molecular weight bands of 24-35kDa specific for T. canis. Children were considered seropositive if their serum reacted with TcES when diluted to a titer of 1:32. Questionnaires concerning possible risk factors were given to the schoolchildren to acquire data on this infection. The overall seroprevalence of Toxocara infection was 86.1% (315/366). The logistic regression analysis of risk factors showed that children's age (odds ratio (OR)=2.88, 95% confidence interval (CI)=1.08-7.66, p=0.03), contact with dogs (OR=0.51, 95% CI=0.28-0.94, p=0.03), the age of the dog (OR=0.34, 95% CI=0.18-0.68, p=0.002), the feeding location of the dog (OR=0.31, 95% CI=0.12-0.79, p=0.01), the consumption of raw vegetables (OR=0.89, 95% CI=0.54-1.48, p=0.004), and the drinking of unboiled water (OR=0.48, 95% CI=0.26-0.90, p=0.02) were risk factors associated with Toxocara infection. Although there was a high awareness of dogs being hosts of some parasites in this study, not much was known about T. canis. This is the first serological investigation of T. canis infection among primary schoolchildren in southern Nigeria. The high seroprevalence recorded is an indication of high transmission with the consequent risk of visceral or ocular larval migrans and neurologic toxocariasis in these children. Our findings suggest the need for prompt interventional measures, particularly health education on personal hygiene.

Toxoplasma gondii infection: seroprevalence and associated risk factors among primary schoolchildren in Lagos City, Southern Nigeria

INTRODUCTION: Toxoplasma gondii infection has been described as the most widespread zoonotic infection of humans and other animals. Information concerning T. gondii infection among schoolchildren is unavailable in Lagos City, Nigeria. METHODS: This cross-sectional study investigated the seroprevalence and risk factors associated with T. gondii infection among primary schoolchildren (PSC) from a community located in the center of Lagos, southern Nigeria, from November 2013 to March 2014. A total of 382 PSC were screened for the presence of sera anti-T. gondii antibodies using a latex agglutination test (TOXO Test-MT, Tokyo, Japan). A cutoff titer of ≥ 1:32 was considered positive, while titers ≥ 1:1,024 indicated high responders. Questionnaires were also used to obtain data on possible risk factors from parents/guardians. RESULTS: The overall seroprevalence was 24% (91/382), and 83.5% (76/91) of seropositive PSC were classified as high responders. Among the risk factors tested, including contact with cats and soil, consumption of raw meat and vegetables, and drinking unboiled water, none showed statistical significance after multivariate adjustment. No associations were observed among age, gender, body mass index (BMI), and parents' occupation/educational level. CONCLUSIONS: The findings in this study show evidence of active infection, and hence, there is need for urgent preventive measures in this city. Further investigation is required to clarify the transmission routes. Policy makers also need to initiate prevention and control programs to protect pregnant women and immunocompromised patients in particular because they are more severely affected by T. gondii infection. .

Biophysical analysis of astrocytes apoptosis triggered by larval E/S antigen from cerebral toxocarosis-causing pathogen Toxocara canis.

Toxocarosis is a zoonosis caused by the transmission of the Toxocara canis (T. canis) larvae to humans. Its infectious third-stage larvae can invade the brains of paratenic hosts. The resultant brain damage can result in cerebral toxocarosis (CT). Astrocytes have important neurotrophic and neuroprotective functions in the brain. Substantial studies have shown that astrocyte apoptosis may contribute to the pathogenesis of many acute and chronic neurodegenerative disorders. We propose an alternation detection method, a combination of the astigmatic detection microscopy (ADM) and atomic force microscopy (AFM) techniques, to investigate the apoptosis of astrocytes triggered with T. canis larval excretory/secretory (Tc E/S) antigen. The variation in the pathology of a cell's morphological changes was investigated with ADM and AFM analyses and then confirmed by western blotting. The results showed that the round cells increased as the concentration of Tc E/S antigen and incubated time increased. In addition, the mean height of apoptotic cells was approximately twice that of untreated normal cells, which meant there was correlation between the Tc E/S antigen treatment and cell height. For each cleaved caspase-3 in the cells cocultured with Tc E/S antigen and incubated for 9 h, the corresponding intensities increased about 34-fold (34.4 ± 1.8) compared with those of the control cells. This method can provide researchers with a perspective for understanding the limited information on the mechanism of astroglial injury and death during a T. canis larval invasion in a brain infection.

Factors affecting disease manifestation of toxocarosis in humans: genetics and environment.

Toxocara canis is regarded as the main cause of human toxocarosis but the relative contribution of T. cati is probably underestimated; serological and other diagnostic methods used in most studies of this zoonotic disease do not distinguish between the two parasites. The definitive hosts for T. canis are caniidae. Pups generally have higher infection rates than adult animals and are a major source of eggs in the environment. Humans usually acquire T. canis infection by accidental ingestion of embryonated eggs or encapsulated larvae from the environment or contaminated food, such infections may lead to visceral larva migrans (VLM), ocular larva migrans (OLM) or covert toxocarosis (CT). Although a mixed Th1- and Th2-mediated immunological response, particularly with high levels of IgE and eosinophilia is observed, the underlying mechanisms of molecular and immunopathogenesis for the development of the symptomatic syndromes of VLM, OLM, or of asymptomatic CT are largely unclear. Studies have indicated that immunological defences against various infectious diseases may be highly influenced by complex interactions of environmental and host genetic factors e.g. MHC class I and II, also known as human leucocyte antigen (HLA). Toxocara spp. infections are associated with a polarized CD4(+) Th2 response with high IgE levels and eosinophilia, mediated mainly by HLA class II molecules. Associations have been made between HLA class II and pathological severity and host genetic effects on exposure to infection. Recent research suggests Foxp3(+) CD4(+)CD25(+)-expressing T regulatory (Treg) cells play a role in regulation of the immunopathology of granulomas in experimental toxocaral granulomatous hepatitis and in enhanced expression of TGF-ß1, which is an important factor for the local survival and function of Treg observed during T. canis invasion in the mouse small intestine, liver, muscle, and brain. Since the potential susceptibility loci HLA class II molecules, are considered involved in the regulation of a Th2-dominant immunity which is highly controlled by Foxp3(+) CD4(+)CD25(+) Treg cells by stimulation through TGF-ß1, which thus provides a beneficial environment to T. canis larvae but severe injuries to local organs. However, TGF-ß1 variant Leu10Pro known to be involved in disease severity warrants further elucidation as this too may have a role in the severity of human toxocarosis. Exploration of TGF-ß1 polymorphism, Foxp3(+) CD4(+)CD25(+) Treg cells, and MHC polymorphisms may allow insight into the contribution made by environmental and genetic factors in influencing disease syndrome type and severity in humans with toxocarosis.

Enterobius vermicularis infection is well controlled among preschool children in nurseries of Taipei City, Taiwan.

INTRODUCTION: Whether Enterobius vermicularis (pinworm) infections among preschool children in Taipei City had truly declined was investigated. METHODS: A total of 6,661 preschool children from 28 nurseries were randomly selected from 4 major geographic districts in Taipei City to examine the status of pinworm infection by using adhesive thin cellophane tape swab method. RESULTS: The overall prevalence of pinworm infection was 0.5% (30/6,661). Boys (0.6%; 21/3,524) had higher prevalence than girls (0.3%; 9/3,137) (p=0.06). Southern district (0.6%; 10/1,789) showed insignificantly higher prevalence than Western district (0.2%; 1/606) (p=0.22). CONCLUSIONS: Pinworm screening program remains necessary for some parts of Taipei City.

Toxoplasma gondii infection: relationship between seroprevalence and risk factors among primary schoolchildren in the capital areas of Democratic Republic of São Tomé and Príncipe, West Africa.

BACKGROUND: The status of Toxoplasma gondii infection among primary schoolchildren (PSC) of the Democratic Republic of São Tomé and Príncipe (DRSTP), West Africa, remains unknown to date. METHODS: A serologic survey and risk factors associated T. gondii infection among PSC in the DRSTP was assessed by the latex agglutination (LA) test and a questionnaire interview including parents' occupation, various uncomfortable symptoms, histories of eating raw or undercooked food, drinking unboiled water, and raising pets, was conducted in October 2010. Schoolchildren from 4 primary schools located in the capital areas were selected, in total 255 serum samples were obtained by venipuncture, of which 123 serum samples were obtained from boys (9.8 ± 1.4 yrs) and 132 serum samples were obtained from girls (9.7 ± 1.3 yrs). RESULTS: The overall seroprevalence of T. gondii infection was 63.1% (161/255). No significant gender difference in seroprevalence was found between boys (62.6%, 77/123) and girls (63.6%, 84/132) (p = 0.9). The older age group of 10 years had insignificantly higher seroprevalence (69.9%, 58/83) than that of the younger age group of 8 year olds (67.7%, 21/31) (p = 0.8). It was noteworthy that the majority of seropositive PSC (75.8%, 122/161) had high LA titers of ≥1: 1024, indirectly indicating acute or repeated Toxoplasma infection. Parents whose jobs were non-skilled workers (73.1%) showed significantly higher seroprevalence than that of semiskilled- (53.9%) or skilled workers (48.8%) (p < 0.05). Children who had a history of raising cats also showed significantly higher seroprevalence than those who did not (p < 0.001).Children who claimed to have had recent ocular manifestation or headache, i.e. within 1 month, seemed to have insignificantly higher seroprevalence than those who did not (p > 0.05). CONCLUSIONS: Parents' educational level and cats kept indoors seemed to be the high risk factors for PSC in acquisition of T. gondii infection. While, ocular manifestation and/or headache of PSC should be checked for the possibility of being T. gondii elicited. Measures such as improving environmental hygiene and intensive educational intervention to both PSC and their parents should be performed immediately so as to reduce T. gondii infection of DRSTP inhabitants including PSC and adults.