Laboratory diagnosis of Schistosomiasis in areas of low transmission: a review of a line of research

After 57 years of successful control of schistosomiasis in Venezuela, the prevalence and intensity of infection have declined. Approximately 80% of the individuals eliminate less than 100 eggs/g of stools, therefore morbidity is mild and the majority are asymptomatic. The sensitivity of Kato-Katz decreases to approximately 60%. Available serological methods for the detection of circulating antigens only reach a 70% of sensitivity. Tests based on the detection of antibodies by immunoenzymatic assays have been improved. The circumoval precipitine test has shown a high sensitivity (97%), specificity (100%), and correlation with oviposition, being considered the best confirmatory diagnostic test. Additionally to the classical immunoenzymatic assays, the development of the alkaline phosphatase immunoassay, allowed to reach a 100% specificity with an 89% sensitivity. Recently, we have developed a modified ELISA in which the soluble egg antigen is treated with sodium metaperiodate (SMP-ELISA) in order to eliminate the glycosilated epitopes responsible for the false positive reactions. The specificity and sensitivity reaches 97% and 99%, respectively. Synthetic peptides from the excretory-secretory enzymes, cathepsin B (Sm31) legumain (Sm32) and cathepsin D (Sm45), have been synthesized. The combination of two peptides derived from the Sm31 have been evaluated, reaching a sensitivity of 96% when analyzed independently and with a 100% specificity. Antibodies raised in rabbits against peptides derived from the Sm31 and Sm32 are currently evaluated in two different antigen-capture-based assays. The development of a simple, cheap and reliable test that correlates with parasite activity is a major goal.

Reproductive system abnormalities in Schistosoma mansoni adult worms isolated from Nectomys squamipes (Muridae: Sigmodontinae): brightfield and confocal laser scanning microscopy analysis

Schistosoma mansoni adult worms with genital anomalies isolated from Nectomys squamipes (Muridae: Sigmodontinae) were studied by confocal laser scanning microscopy under the reflected mode. One male without testicular lobes (testicular agenesia/anorchism) and two females, one with an atrophied ovary and another with 17 uterine eggs, were identified. The absence of testicular lobes occurred in a worm presenting otherwise normal male adult characteristics: tegument, tubercles and a gynaecophoric canal with spines. In both female specimens the digestive tube showed a vacuolated appearance, and the specimen with supernumerary uterine eggs exhibited a developing miracidium and an egg with a formed shell. The area of the ventral sucker was similar in both specimens however the tegument thickness, ovary and vitelline glands of the specimen with the atrophied ovary were smaller than those of the one with supernumerary eggs. These reported anomalies in the reproductive system call attention to the need to improve our understanding of genetic regulation and the possible role of environmental influences upon trematode development.

Some coccidial parasites of the lizard Amphisbaena alba (Reptilia: Amphisbaenia: Amphisbaenidae)

Five parasites are described in the lizard Amphisbaena alba (Amphisbaenidae) from the state of Pará, North Brazil. Mature oocysts of Choleoeimeria amphisbaenae n. sp., are passed already mature in the faeces. They are ellipsoidal-cylindrical, average 33.7 x 22.8 µm and are devoid of micropyle, oocyst residuum or polar body. The colourless wall is smooth and of 2 layers. The 4 dizoic sporocysts have no Stieda body and average 13 x 9.3 µm. Endogenous stages develop in the epithelial cells of the gall-bladder in the manner described for the genus and may cause extensive tissue damage. Sporulation of Isospora capanemaensis n. sp., is completed 3 days after the oocysts are voided in the faeces. They average 14.8 x 14.5 µm and have no micropyle, oocyst residuum or polar body. The 2 tetrazoic sporocysts are pear-shaped, average 8.6 x 6.6 and have an inconspicuous Stieda body. Endogenous development is in the epithelial cells of the ileum, and heavy infections cause considerable tissue destruction. Multisporocystic oocysts passed in the faeces of one A. alba possibly originated from an invertebrate host ingested by the lizard. A globidium-like cyst in the digestive tract of A. alba measured 105 x 85 µm and contained many hundreds of merozoites. A stained kidney smear of the same lizard revealed the presence of an unidentified parasite producing multinucleate cyst-like stages.

Carcinoembryonic antigen (CEA): demonstration of a partial identity between CEA and a normal glycoprotein.

The carcinoembryonic antigen of the human digestive tract (CEA), described by Gold as a glycoprotein specific for digestive carcinomatous and foetal tissues, was found to have common antigenic determinants with a glycoprotein of smaller size extracted from normal adult tissues. This observation suggests that only a part of the CEA molecule carries the onco-foetal specificity. It also has practical implications regarding the radioimmunoassay for CEA used for the diagnosis of certain carcinomas.

Evolution of ascariasis in humans and pigs: a multi-disciplinary approach

The nematode parasite Ascaris lumbricoides infects the digestive tracts of over 1.4 billion people worldwide, and its sister species, Ascaris suum, has infected a countless number of domesticated and feral pigs. It is generally thought that the putative ancestor to these worms infected either humans or pigs, but with the advent of domestication, they had ample opportunity to jump to a new host and subsequently specialize and evolve into a new species. While nuclear DNA markers decisively separate the two populations, mitochondrial sequences reveal that three major haplotypes are found in A. suum and in A. lumbricoides, indicating either occasional hybridization, causing introgression of gene trees, or retention of polymorphism dating back to the original ancestral species. This article provides an illustration of the combined contribution of parasitology, archaeoparasitology, genetics and paleogenetics to the history of ascariasis. We specifically investigate the molecular history of ascariasis in humans by sequencing DNA from the eggs of Ascaris found among ancient archeological remains. The findings of this paleogenetic survey will explain whether the three mitochondrial haplotypes result from recent hybridization and introgression, due to intensive human-pig interaction, or whether their co-occurrence predates pig husbandry, perhaps dating back to the common ancestor. We hope to show how human-pig interaction has shaped the recent evolutionary history of this disease, perhaps revealing the identity of the ancestral host.

Wholegrains

With all the choice available these days it can be easy to forget just how good regular foods can be. Take wholegrain breads for example. They contain carbohydrates, fiber, iron and B vitamins. They're real superfoods that can keep you going for longer and take care of your digestive system.

Telephone Survey of Infectious Intestinal Disease in the Republic of Ireland

Infectious intestinal disease is a disease of the digestive system caused by infectious agents. Most infectious intestinal disease (IID) is self-limiting, requiring no clinical intervention, but it causes a substantial burden to the population through healthcare usage and absenteeism. Understanding the magnitude, distribution and demographic factors associated with IID is key to its mitigation. The cases and outbreaks of human disease detected via surveillance represent but a small proportion of the true burden of disease in the population, and special studies are needed periodically in order to be able to extrapolate true population experience from what is reported via surveillance. One way to identify the true extent of IID is to estimate illness in the community, and not just at the point where the individual has made contact with the health services.

HygR and PurR plasmid vectors for episomal transfection of Trypanosoma cruzi

This work describes the development and functional testing of two episomes for stable transfection of Trypanosoma cruzi. pHygD contained the 5'- and 3'- flanking regions of the gene encoding the cathepsin B-like protease of T. cruzi as functional trans-splicing and polyadenylation signals for the hygR ORF. Evidence is presented to support extrachromosomal maintenance and organization as tandem repeats in transfected parasites. pPac was derived from pHygD by replacement of the entire hygR ORF with a purR coding region. The ability to modify pHygD and the availability of the complete DNA sequence make these plasmids useful tools for the genetic manipulation of T. cruzi.

Growing up in Ireland. Key findings: infant cohort (at 3 years).

 The latest results from the study paint a picture of how these families are faring across a range of areas in their lives including their health, family life and financial and economic circumstances. In general the findings show that three-year-olds in Ireland are in good health with a few notable public health and related issues (including overweight and obesity), there is overall stability in family structures over the short term and that the recession has had a substantial effect on families with young children over the last number of years. These are the first longitudinal findings from the study. The first wave of fieldwork with the families of the Infant Cohort included approximately 11,100 nine-month-olds, their parents and carers. Interviews began in September 2008 and were completed in March 2009. Interviews for the second round of interviews with this cohort took place between January and August 2011. A total of 90% of the original sample of nine-month-olds were successfully re-interviewed. (A full download of the results released today, presented in three briefing documents can be found by clicking here. Key findings include: Health â?¢ Most of the children were described as being in good health; 75% were rated as very healthy and a further 23% were rated as healthy, but a few minor problems. Girls were more likely to be reported as very healthy (78%) compared with boys (72%). â?¢ One in four or almost one quarter of three-year-old children were overweight (19%) or obese (6%). â?¢ Childrenâ?Ts weight was related to household social class. 5% of children in families in the professional/managerial group were classified as obese at three years of age compared with 9% of those in the most disadvantaged social class group. However, at least one-fifth of children in every social class were overweight. â?¢ Childrens consumption of energy-dense foods such as crisps, sweets, chips, and non-diet fizzy drinks increased as parental education fell. 63% of children whose mother had a lower secondary education or less ate at least one portion of crisps compared with 36% of those from degree-level backgrounds, although consumption of biscuits/chocolates was over 70% for both groups of children. â?¢ Two-thirds (66%) of three-year-olds had received at least one course of antibiotics in the 12 months preceding the interview. Children with a full medical card (35% of the sample) or a GP-only medical card (5% of the sample) were more likely to have received a course of antibiotics than â?¢ Children with a full medical card received a higher number of antibiotic courses on average (2.6) compared with those without a medical card (2.1). â?¢ Just under 16% of three-year-old children were reported as having at least one longstanding illness, condition or disability. The most commonly reported illness types included Asthma (5.8%), Eczema/Skin allergies (3.9%) and Food/digestive allergies (1.2%) Family Life and Childcare â?¢ While the overall distribution of family structure was stable, there have been transitions from one-parent families to two-parent families and vice-versa over the 27 months between interview â?" approximately 2 to 3 percent in each direction. â?¢ 50% of three year olds were in some form of non-parental childcare for eight or more hours a week. The most common form used was centre-based childcare which almost tripled between nine months and three years, from 11% to 30%. â?¢ A similar percentage of grandparents were caring for children at both nine months and three years, 12% and 11% respectively. A total of 10% of three-year-olds were being minded by a childminder, an increase of 3 percentage points from when the children were nine months of age. â?¢ Children who were in some form of non-parental childcare were spending an average of 23 hours a week in their main type of childcare. â?¢ At time of interview the vast majority of mothers reported that they had regular contact with the Study Childâ?Ts grandparents (91%). In offering support to parents, grandparents were most likely to babysit (50%), and buy clothes (40%) at least on a monthly basis. One-parent families were more likely than two-parent families to receive financial support from grandparents with just under one-third (66%) of one-parent families receiving financial support from grandparents at least once every three months. â?¢ The most frequently used discipline technique was â?~discussing or explaining why the behaviour was wrongâ?T, with 63% of mothers saying they always did this. â?¢ 12% of mothers said they used â?~smackingâ?T as a form of discipline now and again and less than 1% used â?~smackingâ?T as a form of discipline more frequently. Over half reported that they never smacked the Study Child. Financial and Economic Circumstances â?¢ Just over half (53%) of mothers of three-year-olds worked outside the home, 38% said they were on home duties and 6% said they were unemployed. â?¢ The biggest change in terms of the work status of three-year-oldsâ?T parents was an increase in the percentage of unemployed fathers â?" 6% when the child was nine months rising to almost 14% when s/he was three years of age. â?¢ 61% of families of three-year-olds reported experiencing difficulties in making â?~ends meetâ?T. This was a substantial increase from 44% in the first round of interviews when the children were nine-months-old. â?¢ Almost two thirds (63%) of all families with three-year-olds reported that the recession had had a very significant or significant effect on them. â?¢ The most frequently recorded effects were: a reduction in wages (63%); canâ?Tt afford luxuries (54%), social welfare reduction (53%) and canâ?Tt afford/cut back on basics (32%). Growing Up in Ireland is a Government funded study tracking the development of two nationally representative cohorts of children: an Infant Cohort which was interviewed initially at nine months and subsequently at three years of age; and a Child Cohort which was interviewed initially at nine years and subsequently at 13 years of age. The study is being conducted by a consortium of researchers led by the Economic and Social Research Institute (ESRI) and Trinity College Dublin. For Further Information Please Contact: Jillian Heffernan Communications Officer, Growing Up in Ireland Tel: 01 896 3378 Mobile: 087 9016880This resource was contributed to our repository by the National Documentation Centre on Drug Use.

Escalating epidemiology of eosinophilic esophagitis: 21 years of prospective population-based documentation in Olten county

Background and Aims: Eosinophilic Esophagitis (EoE) is detected with a dramatically increasingfrequency during the last decades. However, it is still unknown whether this reflects atrue increase in incidence or just an increased awareness by gastroenterologists. We therefore,prospectively assessed incidence and prevalence of EoE in an epidemiologically well definedindicator area over the last 21 years. Methods: Olten County is an area of approximately90,000 inhabitants without pronounced demographic changes during the last two decades.Two EoE-experienced gastroenterologists and one pathology centre are responsible forcovering the gastroenterological service of the area. No public programs for increasingawareness of EoE were implemented in this region. Since 1989 all individuals with confirmeddiagnosis of EoE living in Olten County were entered prospectively into the database. Results:Forty-six patients (76% males, mean age 41±16 yrs) were diagnosed with EoE between1989 and 2009. Ninety-four percent of patients presented with dysphagia. An average annualincidence rate of 1.88/100,000 was found (range 0-8) with a marked increase in the periodfrom 2004 to 2009. The cumulative EoE prevalence rose up to 35.1/100,000 inhabitantsin 2009. No significant change was observed for the median diagnostic delay, as it was 3years from 1989 to 1998 and 2 years from 1999 to 2009 with age < 40 years representinga risk factor for retarded diagnosis. The number of upper endoscopies per year increasedby 63% in the period from 1999 to 2009 compared to the years 1989 to 1998 which ismarkedly less then the increase in the incidence rate of 150% for the same periods. Conclusions:Over the last 21 years, a significant increase in EoE incidence and prevalence wasfound in an epidemiologically stable indicator region of Switzerland. The constant diagnosticdelay, the number of newly diagnosed EoE cases that was much more pronounced thanthe modest increase of performed upper endoscopies, as well as the lack of EoE awarenessprograms in Olten County indicates a true increase in EoE incidence.

Severity of endoscopically detected esophageal inflammatory and fibrostenotic features correlates with degree of esophageal eosinophilia in adults with eosinophilic esophagitis

Background: Eosinophilic esophagitis (EoE) has emerged as a leading cause of dysphagia in adults. Characteristic esophageal features on endoscopy include structural/fibrostenotic (rings, narrow caliber, strictures) and inflammatory manifestations (longitudinal furrows, exudates, edema). Aim: The purpose of this study was to correlate the clinical, endoscopic and histopathologic features in adult EoE patients. Methods: A total of 106 encounters of 81 patients with EoE were analyzed. Data included an EoE-directed symptom-severity patient questionnaire evaluating symptoms of dysphagia (frequency, intensity, duration), meal duration, chest pain, and overall symptom severity. Video recordings of endoscopies were reviewed in a blinded manner using a classification and grading scheme for the esophageal features of EoE. Histopathology was reviewed for peak eosinophil count/high power field by pathologists blinded to the patients' clinical status. Associations between endoscopic features, histology and symptoms were evaluated using the Spearman rank correlation analysis. Results: The endoscopic severity of both structural and inflammatory esophageal features of EoE, including rings, exudates, longitudinal furrows, and edema, correlated significantly with peak eosinophil counts (see Table 1). Presence of "crepe paper mucosa" did not demonstrate significant association with peak eosinophil counts. Both structural (rings, narrow-caliber esophagus and strictures) and inflammatory (furrows, exudates and edema) composite endoscopic scores demonstrated a strong correlation with peak eosinophil counts. The strongest association with the degree of esophageal eosinophilia was found with a combination of both structural and inflammatory findings (p < 0.0001). The esophageal diameter (in mm) was negatively correlated with overall symptom severity (Spearman's rho = -0.4883, P = 0.0339). None of the individual or combined patient reported symptoms correlated significantly with either endoscopic or histopathologic findings. Conclusion: The severity of both structural and inflammatory endoscopic features associated with EoE is significantly associated with the degree of esophageal eosinophilia. Patient reported symptom severity was not associated with the degree of esophageal eosinophilia. Esophageal stricture diameter was inversely correlated with EoE symptom severity. The prognostic and therapeutic implications of these observations need to be determined.

Physiological changes in Biomphalaria glabrata say, 1818 (Pulmonata: Planorbidae) caused by sub-lethal concentrations of the latex of Euphorbia splendens var. hislopii N.E.B (Euphorbiaceae)

Molluscides have been used as one of the strategies to control schistosomiasis. Many plant extracts with molluscidal effects have been tested, but the action of the latex of Euphorbia splendens var. hislopii is considered the most promising because it meets the recommendations of the World Health Organization (WHO). The objective of this study was to determine the lethal dose and identify the effects of the different doses of latex of E. splendens var. hislopii on the physiology of Biomphalaria glabrata submitted to treatment for 24 h. The concentrations of glucose, uric acid and total proteins in the hemolymph and of glycogen in the digestive gland and cephalopodal mass were determined. The LD50 value was 1 mg/l. The highest escape index was found to be at a concentration of 0.6 mg/l. The results showed that the latex of E. splendens var. hislopii caused a sharp reduction in the reserves of glycogen in the digestive gland and elevation of the protein content in the hemolymph of B. glabrata.

Single and concomitant experimental infectionsby Endotrypanum spp. and Leishmania (Viannia) guyanensis (Kinetoplastida: Trypanosomatidae) in the Neotropical sand fly Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1) two strains of Endotrypanum, (2) cloned versus primary sample of one strain of Endotrypanum, (3) Endotrypanum versus Leishmania guyanensis, and (4) the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.

Aspartic protease activities of schistosomes cleave mammalian hemoglobins in a host-specific manner

We examined the efficiency of digestion of hemoglobin from four mammalian species, human, cow, sheep, and horse by acidic extracts of mixed sex adults of Schistosoma japonicum and S. mansoni. Activity ascribable to aspartic protease(s) from S. japonicum and S. mansoni cleaved human hemoglobin. In addition, aspartic protease activities from S. japonicum cleaved hemoglobin from bovine, sheep, and horse blood more efficiently than did the activity from extracts of S. mansoni. These findings support the hypothesis that substrate specificity of hemoglobin-degrading proteases employed by blood feeding helminth parasites influences parasite host species range; differences in amino acid sequences in key sites of the parasite proteases interact less or more efficiently with the hemoglobins of permissive or non-permissive hosts.

Perioperative nutrition in abdominal surgery: recommendations and reality.

Introduction. Preoperative malnutrition is a major risk factor for increased postoperative morbidity and mortality. Definition and diagnosis of malnutrition and its treatment is still subject for controversy. Furthermore, practical implementation of nutrition-related guidelines is unknown. Methods. A review of the available literature and of current guidelines on perioperative nutrition was conducted. We focused on nutritional screening and perioperative nutrition in patients undergoing digestive surgery, and we assessed translation of recent guidelines in clinical practice. Results and Conclusions. Malnutrition is a well-recognized risk factor for poor postoperative outcome. The prevalence of malnutrition depends largely on its definition; about 40% of patients undergoing major surgery fulfil current diagnostic criteria of being at nutritional risk. The Nutritional Risk Score is a pragmatic and validated tool to identify patients who should benefit from nutritional support. Adequate nutritional intervention entails reduced (infectious) complications, hospital stay, and costs. Preoperative oral supplementation of a minimum of five days is preferable; depending on the patient and the type of surgery, immune-enhancing formulas are recommended. However, surgeons' compliance with evidence-based guidelines remains poor and efforts are necessary to implement routine nutritional screening and nutritional support.