Performance of Sahli and colour scale methods in diagnosing anaemia among school children in low prevalence areas

Our aim was to compare the performance of the Sahli and Colour Scale methods in diagnosing anaemia in school children, where the prevalence of anaemia is low and the haemoglobin level ranges from mild to moderate (8-11 g/dl). The study was conducted in February 2001, in Qena Governorate, Upper Egypt. The haemoglobin level measured by the two methods in each child were compared with the result obtained by using a portable haemoglobin photometer 'HemoCue'. A total of 149 school children were included in the study. Using HemoCue, 17.4% children were anaemic; using the Sahli method (SM), 66.4% children were anaemic; and using the Haemoglobin Colour Scale (HCS) method, 57.7% children were anaemic. Neither method detected any cases of severe anaemia (Hb < 7 g/dl). Both the Sahli and Colour Scale methods are sensitive but have low specificity, giving a high rate of false positive results. Both methods perform perform very similarly in haemoglobin measurement; they fulfil many of the criteria for their use at primary health care level and detect almost all cases of anaemia in a given population, even if the level of anaemia is mild. Standards for collection, handling and disposal of blood samples are guaranteed more easily by the HCS than the SM. Moreover, lay people can easily manage the HCS with success after brief training. We suggest to gradually replace the SM by the HCS method in primary health care (PHC) centres. Where anaemia levels are moderate to mild, the use of SM and HCS as tools to define anaemia prevalence might be limited, as they often label healthy individuals as anaemic. Both methods remain a useful diagnostic tool to confirm the diagnosis of clinically suspected anaemia in areas where the prevalence of anaemia is low and the haemoglobin level ranges from mild to moderate.     

μ-Conotoxins that differentially block sodium channels NaV1.1 through 1.8 identify those responsible for action potentials in sciatic nerve

Voltage-gated sodium channels (VGSCs) are important for action potentials. There are seven major isoforms of the pore-forming and gate-bearing α-subunit (Na(V)1) of VGSCs in mammalian neurons, and a given neuron can express more than one isoform. Five of the neuronal isoforms, Na(V)1.1, 1.2, 1.3, 1.6, and 1.7, are exquisitely sensitive to tetrodotoxin (TTX), and a functional differentiation of these presents a serious challenge. Here, we examined a panel of 11 μ-conopeptides for their ability to block rodent Na(V)1.1 through 1.8 expressed in Xenopus oocytes. Although none blocked Na(V)1.8, a TTX-resistant isoform, the resulting "activity matrix" revealed that the panel could readily discriminate between the members of all pair-wise combinations of the tested isoforms. To examine the identities of endogenous VGSCs, a subset of the panel was tested on A- and C-compound action potentials recorded from isolated preparations of rat sciatic nerve. The results show that the major subtypes in the corresponding A- and C-fibers were Na(V)1.6 and 1.7, respectively. Ruled out as major players in both fiber types were Na(V)1.1, 1.2, and 1.3. These results are consistent with immunohistochemical findings of others. To our awareness this is the first report describing a qualitative pharmacological survey of TTX-sensitive Na(V)1 isoforms responsible for propagating action potentials in peripheral nerve. The panel of μ-conopeptides should be useful in identifying the functional contributions of Na(V)1 isoforms in other preparations.     

Detection of Toxoplasma gondii DNA and specific antibodies in high-risk pregnant women

Primary maternal infection with toxoplasmosis during pregnancy is frequently associated with transplacental transmission to the fetus. This study was conducted to test the utility of a polymerase chain reaction (PCR) assay to detect recent infections with Toxoplasma in pregnant women. One hundred forty-eight women with high-risk pregnancies who had abnormal pregnancy outcomes (cases) and 100 with normal pregnancies (controls) were tested for the presence of Toxoplasma DNA in their blood by a nested PCR and specific antibodies to Toxoplasma by an enzyme-linked immunosorbent assay. The IgG results of the cases differed significantly from those of the controls (54% and 12%, respectively; P < 0.02). Four (2.7%) of the cases were IgM positive, but none of the controls were positive. Detection of Toxoplasma DNA in 20 (8.1%) of the IgG-positive cases suggests a recent infection. The risk factors associated with the infection were eating raw meat and contact with soil. The diagnostic serology of recent infection in early pregnancy could be confirmed by a positive Toxoplasma-specific PCR result in blood samples collected in the first half of pregnancy, even in the presence of serologic results difficult to interpret due to the lack of sequential follow-up during pregnancy.     

Adenylate cyclase activity in human pancreatic adenocarcinoma cell lines

Summary Conclusion BxPC-3, Hs 766T, Capan-2, Panc-1, and Capan-1 cells possess receptors for VIP and β-adrenergic agonists that are functionally coupled to adenylate cyclase. In this respect, they resemble pancreatic duct cells. However, we speculate that the process of neoplastic transformation has either downregulated the expression of secretin receptors or led to a defect in the receptor itself, placing a question mark over the usefulness of these adenocarcinoma cell lines as models of the pancreatic ductal epithelium. Background Because of the importance of ducts in pancreatic disease, we wished to establish which duct cells receptors are functional on adenocarcinoma cell lines. Methods We investigated the expression of agonist-stimulated adenylate cyclase activity in six human pancreatic adenocarcinoma cell lines. Known stimulants of pancreatic ductal secretion, VIP, PHI, secretin, β-adrenergic, and dopamine, were tested. Results For responsive cell lines, VIP was the most effective stimulant followed by adrenaline, isoprenaline, PHI, and secretin. Dopamine was without effect. Since high concentrations of PHI and secretin were required to stimulate cyclase activity, their effect is probably mediated by VIP receptors. Based on the degree of stimulation observed with the individual agonists, Hs 766T and BxPC-3 were the most responsive cell lines, followed by Capan-2 and Capan-1, and finally Panc-1. MIAPaCa-2 cells did not respond to any of the agonists tested.     

An inducible mouse model for microvillus inclusion disease reveals a role for myosin Vb in apical and basolateral trafficking

Microvillus inclusion disease (MVID) is a rare intestinal enteropathy with an onset within a few days to months after birth, resulting in persistent watery diarrhea. Mutations in the myosin Vb gene (MYO5B) have been identified in the majority of MVID patients. However, the exact pathophysiology of MVID still remains unclear. To address the specific role of MYO5B in the intestine, we generated an intestine-specific conditional Myo5b-deficient (Myo5b^fl/fl;Vil-CreERT2) mouse model. We analyzed intestinal tissues and cultured organoids of Myo5b^fl/fl;Vil-CreERT2 mice by electron microscopy, immunofluorescence, and immunohistochemistry. Our data showed that Myo5b^fl/fl;Vil-CreERT2 mice developed severe diarrhea within 4 d after tamoxifen induction. Periodic Acid Schiff and alkaline phosphatase staining revealed subapical accumulation of intracellular vesicles in villus enterocytes. Analysis by electron microscopy confirmed an almost complete absence of apical microvilli, the appearance of microvillus inclusions, and enlarged intercellular spaces in induced Myo5b^fl/fl;Vil-CreERT2 intestines. In addition, we determined that MYO5B is involved not only in apical but also basolateral trafficking of proteins. The analysis of the intestine during the early onset of the disease revealed that subapical accumulation of secretory granules precedes occurrence of microvillus inclusions, indicating involvement of MYO5B in early differentiation of epithelial cells. By comparing our data with a novel MVID patient, we conclude that our mouse model completely recapitulates the intestinal phenotype of human MVID. This includes severe diarrhea, loss of microvilli, occurrence of microvillus inclusions, and subapical secretory granules. Thus, loss of MYO5B disturbs both apical and basolateral trafficking of proteins and causes MVID in mice.Microvillus inclusion disease (MVID) is a rare intestinal enteropathy with autosomal recessive inheritance, which was first described in 1978 (1). MVID patients cannot take up any nutrients and are often completely dependent on parenteral nutrition. The disease is characterized by villus atrophy, (partial) loss of microvilli on the apical plasma membrane of intestinal epithelial cells, and accumulation of intracellular vesicles/vacuoles, containing apical proteins and microvilli (2, 3). In addition, some studies also show mislocalization of apical and basolateral proteins, occasional crypt hyperplasia, and villus fusion (4–6).In the great majority of patients, MVID is caused by mutations in MYO5B, encoding the motorprotein, myosin Vb (5). In two patients, mutations in syntaxin 3 (STX3) caused a variant form of MVID (7). More than 41 unique mutations along the different regions in MYO5B have been identified in MVID patients, including deletions and nonsense, missense, and splice-site mutations (8–10). MYO5B is coding for the actin-based myosin 5b motor protein, which regulates apical membrane trafficking (5, 11). MYO5B functions as a homodimer and has three functional domains: an N-terminal motor domain, a calmodulin-binding domain, and a C-terminal tail, which binds cargo through association with the small GTPases RAB8A and/or RAB11A (12, 13). Altered expression of myosin Vb affects the apical membrane trafficking mechanism in epithelial cells, causing mislocalization of apical brush border proteins, such as villin (vil), CD10, or alkaline phosphatase (ALP) in the cytoplasm of duodenal enterocytes (2, 3, 5), and an increased apical localization of transferrin receptor (5, 14).Although mouse models mimicking certain features of MVID have previously been described, such as Rab8 (15), Cdc42 (16, 17), and Rab11a knockout (KO) mice (18, 19), no mutations in the coding regions of those genes have been reported in human MVID patients. Current in vitro models to study apical trafficking and polarization-associated diseases such as MVID are the parental Caco2 cell line, Caco-BBE, and LS174 W4 cells, in which polarization can be induced in vitro (4, 8, 12, 20). Although valuable knowledge about the function of MYO5B in polarization was gained in these models, the direct relevance of the colon cancer cell lines for the disease is questionable, and diverging results have been obtained with knockdown of MYO5B in the parental Caco2 cells compared with the more polarized Caco-BBE cells (8, 12, 20). As such, we here present an inducible MVID mouse model that recapitulates the genetic defects in man, which allows analysis of the role of MYO5B in a physiological setting and the sequence of events in MVID pathophysiology.     

Survey and genetic characterization of wastewater in Tunisia for Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, Cyclospora cayetanensis and Eimeria spp

The microbial diversity of wastewater used for irrigation and fertilization was assessed using specific polymerase chain reaction (PCR) assays to detect and genotype several pathogenic protists including Cryptosporidium spp., Giardia duodenalis, Cyclospora spp., Eimeria spp. and Enterocytozoon bieneusi. A total of 220 wastewater samples (110 raw, 110 treated) and 12 sludge samples were collected from 2005 to 2008 from 18 treatment plants located throughout Tunisia. Except for Cyclospora, which was detected only once, E. bieneusi (61%), G. duodenalis (28%), Cryptosporidium spp. (27%) and Eimeria spp. (45%) were frequently observed in wastewater and sludge. Sequencing of PCR products showed that C. hominis, C. andersoni, G. duodenalis sub-assemblage A-II and E. bieneusi genotypes D and IV were the most prevalent. An analysis of the distribution of 209 internal transcribed spacer sequences of E. bieneusi originating from wastewater at the 18 treatment plants showed a similar genetic diversity, regardless of the geographical location. The identification of these parasite species and genotypes and of host-specific Eimeria species indicates that the microbial quality of wastewater was impacted by humans, livestock and rodents. Given the public health risks that some of these parasites represent, guidelines on wastewater usage are needed to minimize human exposure to these pathogens.     

Coagulation disorders and inhibitors of coagulation in children from Mansoura,Egypt

Disorders of coagulation in children often prove challenging to the medical care team. The aims of this study were to assess the spectrum and prevalence of coagulation disorders among children attending Mansoura University Children Hospital (MUCH), Mansoura, Egypt. A total of 105 pediatric patients were referred to MUCH. They were divided into two groups: congenital coagulation disorders (75 cases, age 45.36 ± 48.59 months), and acquired coagulation disorders (30 cases, age 56.13 ± 61.61 months). All patients were subjected to thorough history taking including the nature of bleeding, family, past history, mode of inheritance, and detailed physical findings. Hemostatic tests included: platelet count, bleeding time (BT), prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT). Specific tests in the congenital group include assay of coagulation factors according to each disorder, Von Willebrand factor assay, ristocetin aggregation test, APTT mixing study for detection of inhibitors in complicated hemophilia cases, F VIII C to VWAg ratio with cut off 0.7 for detection of carriers in some hemophilia A families. Congenital disorders constituted 71.4% of the studied cases vs. 28.6% for acquired disorders. Hemophilia A (42.85%), hemophilia B (14.28%) and liver diseases (14.28%) represented the majority of the studied cases. Mild and moderate cases of hemophilia A and B are more frequent than severe cases in both types. Male sex is more frequent than female in the congenital group (94.7 vs. 5.3%, P < 0.001). Direct correlation existed between factor level assay and severity of hemophilia (r = 0.73, P = 0.006). Three mothers and one sister were identified as carrier out of four families. Anti-clotting factors inhibitor was detected in 18.2% of patients with hemophilia A and in 9.1% with hemophilia B. In conclusion, our study found that hemophilias are the most prevalent congenital coagulation disorders among children. Attention must be given for detection of hemophilia carriers and inhibitors of clotting factors.     

Nested association between genetic variation in tryptophan hydroxylase II, bipolar affective disorder, and suicide attempts.

BACKGROUND: Bipolar affective disorder (BPAD) is a common mental illness that is strongly associated with suicide. Suicidal behavior is thought to result from an interaction of genetic, neurobiological, and psychosocial factors and tends to cluster in families, suggesting specific familial factors distinct from those that underlie BPAD itself. Serotonin signaling has long been implicated in both BPAD and suicide, and the gene encoding the brain-expressed isoform of tryptophan hydroxlyase (TPH2) has been described. Markers in TPH2 have been implicated in suicide and major depressive disorder, but the results across studies are inconsistent. No studies have examined TPH2 in large samples of subjects with BPAD and suicide attempts (SA). We tested for a relationship between genetic variation in TPH2 and risk for BPAD and SA in a large family sample. METHODS: The sample consisted of 2018 members of 670 families, ascertained through a sibling pair affected with bipolar I, bipolar II, or schizoaffective-bipolar disorder and diagnosed under DSM-III/IV criteria. Three single nucleotide polymorphisms representing the common haplotypes spanning TPH2 were analyzed. RESULTS: Single-marker analysis failed to detect significant genetic association with BPAD or SA, but the number of informative families was small. Haplotype analysis showed significant association with both BPAD and SA, and the same haplotype was significantly associated with both BPAD and SA in a replication sample. Case-only analysis, stratified by SA, suggested that TPH2 was not an independent genetic risk factor for SA in this sample. CONCLUSIONS: The TPH2 might contribute to the risk of both BPAD and SA in families with BPAD. Further studies are needed to uncover the functional genetic variation that accounts for the observed associations.     

EFFECT OF DIPYRIDAMOLE ON BLOOD GLUCOSE AND LIVER CYCLIC AMP LEVELS AND PLATELET COUNT DURING ENDOTOXAEMIA IN MICE

1. Blood glucose, liver cyclic AMP (cAMP) levels, and platelet count were studied at different times during a 12 h interval after intravenous (i.v.) endotoxin injection (40 mg/kg) in mice. 2. Blood glucose and liver cAMP levels showed a progressive decrease in endotoxic mice and the decrease was significant after 8 and 12 h. 3. Dipyridamole (50 mg/kg) administered intraperitoneally (i.p.) 7 h post-endotoxin improved blood glucose and liver cAMP levels. 4. Platelet counts were decreased after 1 h in endotoxic mice and remained decreased up to 8 h. Dipyridamole administered soon after endotoxin improved platelet counts in endotoxic mice and increased survival rate to 100%.