Cross-sectional estimation of Babesia bovis antibody prevalence in cattle in two contrasting dairying areas in Tanzania

The crude prevalence of antibodies to Babesia bovis infection in cattle was estimated by serology using indirect ELISA during the period January to April, 1999. Sera were obtained from 1395 dairy cattle (of all ages, sexes and breeds) on smallholder farms, the majority being kept under a zero grazing regime. The crude prevalence of antibodies to Babesia bovis was 6 % for Tanga and 12 % for Iringa. The forces of infection based on the age sero-prevalence profile, were estimated at six for Iringa and four for Tanga per 100 cattle years-risk, respectively. Using random effect logistic regression as the analytical method, the factors (variables) of age, source of animals and geographic location were hypothesised to be associated with sero-positivity of Babesia bovis in the two regions.

Amniotic fluid and umbilical cord plasma corticotropin-releasing factor (CRF), CRF-binding protein, adrenocorticotropin, and cortisol concentrations in intraamniotic infection and inflammation at term

Context: Pregnant tissues express corticotropin-releasing factor (CRF), a peptide modulating fetal and placental ACTH and cortisol secretion. These actions are modulated by the locally expressed CRF-binding protein (CRF-BP). Objective: The objective of the study was to determine whether CRF, CRF-BP, ACTH, and cortisol concentrations change in amniotic fluid and umbilical cord plasma in the presence of intraamniotic infection/inflammation (IAI) in women with spontaneous labor at term. Design: This was a cross-sectional study. Setting: The study was conducted at a tertiary referral center for obstetric care. Patients: Patients included women in active labor at term with (n = 39) and without (controls; n = 78) IAI. Main Outcome Measures: Amniotic fluid and umbilical cord plasma concentrations of CRF, CRF-BP, ACTH, and cortisol measured by RIA and immunoradiometric assays were measured. Results: In patients with IAI, amniotic fluid CRF (0.97 +/- 0.18 ng/ml) and CRF-BP (33.06 +/- 5.54 nmol/liter) concentrations were significantly (P < 0.001) higher than in controls (CRF: 0.32 +/- 0.04 ng/ml; CRF-BP: 14.69 +/- 2.79 ml). The umbilical cord plasma CRF and CRF-BP concentrations were significantly (P < 0.001 for all) higher in women with IAI than in controls (CRF: 2.96 +/- 0.35 ng/ml vs. 0.38 +/- 0.18 ng/ml; CRF-BP: 152.12 +/- 5.94 nmol/liter vs. 106.9 +/- 5.97 nmol/liter). In contrast, amniotic fluid and umbilical cord plasma ACTH and cortisol concentrations did not differ between groups. Conclusions: Amniotic fluid and umbilical cord plasma CRF and CRF-BP concentrations are increased in women with spontaneous labor at term and IAI. CRF-BP may modulate CRF actions on ACTH and cortisol secretion, playing a pivotal role in limiting the inflammatory process and thus avoiding an overactivation of the fetal/placental hypothalamus-pituitary-adrenal axis at birth.

Performance of the Quantitative Food Frequency Questionnaire Used in the Brazilian Center of the Prospective Study Natural History of Human Papillomavirus Infection in Men: The HIM Study

The Natural History of Human Papillomavirus (HPV) Infection in Men: The HIM Study is a prospective multi-center cohort study that, among other factors, analyzes participants` diet. A parallel cross-sectional study was designed to evaluate the validity and reproducibility of the quantitative food frequency questionnaire (QFFQ) used in the Brazilian center from the HIM Study. For this, a convenience subsample of 98 men aged 18 to 70 years from the HIM Study in Brazil answered three 54-item QFFQ and three 24-hour recall interviews, with 6-month intervals between them (data collection January to September 2007). A Bland-Altman analysis indicated that the difference between instruments was dependent on the magnitude of the intake for energy and most nutrients included in the validity analysis, with the exception of carbohydrates, fiber, polyunsaturated fat, vitamin C, and vitamin E. The correlation between the QFFQ and the 24-hour recall for the deattenuated and energy-adjusted data ranged from 0.05 (total fat) to 0.57 (calcium). For the energy and nutrients consumption included in the validity analysis, 33.5% of participants on average were correctly classified into quartiles, and the average value of 0.26 for weighted kappa shows a reasonable agreement. The intraclass correlation coefficients for all nutrients were greater than 0.40 in the reproducibility analysis. The QFFQ demonstrated good reproducibility and acceptable validity. The results support the use of this instrument in the HIM Study. J Am Diet Assoc. 2011;111:1045-1051.

Naturally acquired inhibitory antibodies to Plasmodium vivax Duffy binding protein are short-lived and allele-specific following a single malaria infection

The Duffy binding protein of Plasmodium vivax (DBP) is a critical adhesion ligand that participates in merozoite invasion of human Duffy-positive erythrocytes. A small outbreak of P. vivax malaria, in a village located in a non-malarious area of Brazil, offered us an opportunity to investigate the DBP immune responses among individuals who had their first and brief exposure to malaria. Thirty-three individuals participated in the five cross-sectional surveys, 15 with confirmed P. vivax infection while residing in the outbreak area (cases) and 18 who had not experienced malaria (non-cases). In the present study, we found that only 20% (three of 15) of the individuals who experienced their first P. vivax infection developed an antibody response to DBP; a secondary boosting can be achieved with a recurrent P. vivax infection. DNA sequences from primary/recurrent P. vivax samples identified a single dbp allele among the samples from the outbreak area. To investigate inhibitory antibodies to the ligand domain of the DBP (cysteine-rich region II, DBP(II)), we performed in vitro assays with mammalian cells expressing DBP(II) sequences which were homologous or not to those from the outbreak isolate. In non-immune individuals, the results of a 12-month follow-up period provided evidence that naturally acquired inhibitory antibodies to DBP(II) are short-lived and biased towards a specific allele.

Australian women`s experiences of living with hepatitis C virus: results from a cross-sectional survey

Background: Of the estimated 160 000 Australians currently infected with the hepatitis C virus (HCV), over one-third are women and very few have received clinical treatment, with most managing their illness in non-specialist settings. Little is known about the experiences of women living with HCV in the general community. The present study provides the results from the first comprehensive social survey of Australian women's experiences of living with HCV.

Methods: In 2000, a questionnaire was administered to a largely non-clinical sample of women with HCV (n = 462) living in the state of Victoria and the Australian Capital Territory, Australia. The questionnaire was self-administered with a return rate of 75%. The mean age was 35 years and 83% were 'current' or 'past' injecting drug users. The mean time since diagnosis was 4.6 years (SD = 4.0) and the mean time since infection was 10.5 years (SD = 8.2).

Results: Fifty-eight percent of women reported experiencing symptoms related to their HCV, the most common being tiredness (78%) and nausea (44%). Of the sample, 56% currently saw a doctor for their HCV, and while 52% had ever been referred to a specialist, only 17% of the total sample had ever begun interferon-based combination or monotherapy. Forty-eight percent of women reported experiencing less favorable treatment by a health professional because of their HCV. Age-related self-assessed health status was significantly lower than Australian norms, as were SF-12 physical and mental health scores. The SF-12 physical and mental health scores were highly correlated, indicating a significant physical and mental health burden associated with HCV.

Conclusion: The social, physical and mental health needs of women living with HCV are considerable. Most women had not accessed specialist treatment and the response of the primary health care system to HCV-related women's health issues requires improvement.

Blood-stage Plasmodium infection induces CD8+ T lymphocytes to parasite-expressed antigens, largely regulated by CD8α+ dendritic cells

Although CD8+ T cells do not contribute to protection against the blood stage of Plasmodium infection, there is mounting evidence that they are principal mediators of murine experimental cerebral malaria (ECM). At present, there is no direct evidence that the CD8+ T cells mediating ECM are parasite-specific or, for that matter, whether parasite-specific CD8+ T cells are generated in response to blood-stage infection. To resolve this and to define the cellular requirements for such priming, we generated transgenic P. berghei parasites expressing model T cell epitopes. This approach was necessary as MHC class I-restricted antigens to blood-stage infection have not been defined. Here, we show that blood-stage infection leads to parasite-specific CD8+ and CD4+ T cell responses. Furthermore, we show that P. berghei-expressed antigens are cross-presented by the CD8α+ subset of dendritic cells (DC), and that this induces pathogen-specific cytotoxic T lymphocytes (CTL) capable of lysing cells presenting antigens expressed by blood-stage parasites. Finally, using three different experimental approaches, we provide evidence that CTL specific for parasite-expressed antigens contribute to ECM.

Screening pregnant women for chlamydia : what are the predictors of infection?

Objectives: To determine the risk factors associated with chlamydial infection in pregnancy and the sensitivity and specificity of these when used for selective screening.

Methods: A prospective, cross-sectional study of pregnant women aged 16–25 years attending four major public antenatal services across Melbourne, Australia. Between October 2006 and July 2007, women were approached consecutively and asked to complete a questionnaire and to provide a first-pass urine specimen for Chlamydia trachomatis testing using PCR.

Results: Of 1180 eligible women, 1087 were approached and 1044 (88%) consented to participate. Among the 987 women for whom a questionnaire and a definitive diagnostic assay were available, the prevalence of chlamydia was 3.2% (95% CI 1.8 to 5.9). In a multiple logistic regression model, more than one sexual partner in the past year (AOR 11.5; 95% CI 7.1 to 18.5) was associated with chlamydia infection. The use of any antibiotic within 3 months (AOR 0.2; 95% CI 0.1 to 0.6) was associated with a decreased risk of infection. Screening restricted to women who reported more than one sexual partner in the past year would have detected 44% of infections in women aged 16–25 years and would have required only 7% of women to be screened. The addition of those women aged 20 years and under would have required 27% of women to be screened and detection of 72% of infections.

Conclusions: Selective chlamydia screening of pregnant women based on risk factors can improve the yield from screening. However, the potential harm of missed infections among excluded women would need to be considered.

Improving chlamydia knowledge should lead to increased chlamydia testing among Australian general practitioners: a cross-sectional study of chlamydia testing uptake in general practice

Female general practitioners (GPs) have higher chlamydia testing rates than male GPs, yet it is unclear whether this is due to lack of knowledge among male GPs or because female GPs consult and test more female patients.

CD8+ T cells from a novel T cell receptor transgenic mouse induce liver-stage immunity that can be boosted by blood-stage infection in rodent malaria

To follow the fate of CD8+ T cells responsive to Plasmodium berghei ANKA (PbA) infection, we generated an MHC I-restricted TCR transgenic mouse line against this pathogen. T cells from this line, termed PbT-I T cells, were able to respond to blood-stage infection by PbA and two other rodent malaria species, P. yoelii XNL and P. chabaudi AS. These PbT-I T cells were also able to respond to sporozoites and to protect mice from liver-stage infection. Examination of the requirements for priming after intravenous administration of irradiated sporozoites, an effective vaccination approach, showed that the spleen rather than the liver was the main site of priming and that responses depended on CD8α+ dendritic cells. Importantly, sequential exposure to irradiated sporozoites followed two days later by blood-stage infection led to augmented PbT-I T cell expansion. These findings indicate that PbT-I T cells are a highly versatile tool for studying multiple stages and species of rodent malaria and suggest that cross-stage reactive CD8+ T cells may be utilized in liver-stage vaccine design to enable boosting by blood-stage infections.

Upper gastrointestinal histopathological findings in children and adolescents with nonulcer dyspepsia with helicobacter pylori infection

Objectives: The aim of the study was to investigate the histopathological lesions in the upper gastrointestinal mucosa associated with Helicobacter pylori infection in children with nonulcer dyspepsia.Methods: A cross-sectional case-control study was performed on 185 Brazilian children and adolescents (4-17 years, mean 9.5 +/- 2.7 years), 63.2% girls, submitted to upper gastrointestinal endoscopy. The histopathological lesions of the esophageal and gastric mucosa were analyzed in biopsy samples.Results: H pylori infection was identified in 96 children (51.8%). Moderate to severe chronic active gastritis was present in antrum (70.5%) and corpus (45.2%), with higher grading in antrum than in corpus (P<0.05). The topographic distribution of inflammation was pangastritis (61.9%), followed by antral (32.1%) and corpus (5.9%). H pylori density was higher in antrum than in corpus. Intestinal metaplasia was not found in the H pylori-infected group, nor was significant gastric atrophy. The scores for esophagitis were significantly higher (P<0.05) in the noninfected group (1.4 +/- 0.8) than in the H pylori-infected group (1.07 +/- 0.9), with significant negative correlation (r = 0.29; P<0.05) with the scores of gastric inflammation.Conclusions: The prevalence of H pylori infection was high among children with dyspepsia and associated with moderate/severe degrees of gastric inflammation. The high scores of esophagitis in the noninfected group point to 2 distinct groups of pathological conditions sharing similar clinical patterns.

Chlamydial infection in a high risk population: association with vaginal flora patterns

This study aimed to determine the frequency of Chlamydia trachomatis (CT) infection among high risk Brazilian women and evaluate its association with vaginal flora patterns.This was a cross-sectional study, performed in an outpatient clinic of Bauru State Hospital, So Paulo, Brazil. A total of 142 women were included from 2006 to 2008. Inclusion criteria was dyspareunia, pain during bimanual exam, presence of excessive cervical mucus, cervical ectopy or with three or more episodes of abnormal vaginal flora (AVF) in the previous year before enrollment. Endocervical CT testing was performed by PCR. Vaginal swabs were collected for microscopic assessment of the microbial flora pattern. Gram-stained smears were classified in normal, intermediate or bacterial vaginosis (BV), and recognition of Candida sp. morphotypes. Wet mount smears were used for detection of Trichomonas vaginalis and aerobic vaginitis (AV).Thirty-four of 142 women (23.9%) tested positive for CT. AVF was found in 50 (35.2%) cases. The most frequent type of AVF was BV (17.6%). CT was strongly associated with the presence of AV (n = 7, 4.9%, P = 0.018), but not BV (n = 25, 17.6%, P = 0.80) or intermediate flora (n = 18, 12.7%, P = 0.28).A high rate of chlamydial infection was found in this population. Chlamydia infection is associated with aerobic vaginitis.

CaPrx, a Coffea arabica gene encoding a putative class III peroxidase induced by root-knot nematode infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cross-reactive IgE antibody responses to tropomyosins from Ascaris lumbricoides and cockroach

Background: Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma.Objective: To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides.Methods: Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb IA6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program.Results: A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb IA6.Conclusion: Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.

An infection control protocol: effectiveness of immersion solutions to reduce the microbial growth on dental prostheses

This investigation evaluated the effectiveness of an infection control protocol for cleansing and disinfecting removable dental prostheses. Sixty-four dentures were rubbed with sterile cotton swab immediately after they had been taken from patients' mouths. Samples were individually placed in the culture medium and immediately incubated at 37 +/- 2 degreesC. The dentures were scrubbed for 1 min with 4% chlorhexidine, rinsed for 1 min in sterile water and placed for 10 min in one of the following immersion solutions: 4% chlorhexidine gluconate, 1% sodium hypochlorite, Biocide (iodophors) and Amosan (alkaline peroxide). After the disinfection procedures, the dentures were immersed in sterile water for 3 min, reswabbed and the samples were incubated. All samples obtained in the initial culture were contaminated with micro-organisms. All the lower dentures immersed in Biocide showed positive growth, and the upper dentures were positive for growth in six of eight dentures. The 4% chlorhexidine gluconate, 1% sodium hypochlorite and Amosan solutions have been proved effective to reduce the growth of the micro-organisms in the 10 min immersion period. The protocol evaluated in this study seems to be a viable method to prevent cross-contamination between dental personnel and patients.