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Abstract Background Malaria remains a major cause of morbidity and mortality worldwide. Flow cytometry-based assays that take advantage of fluorescent protein (FP)-expressing malaria parasites have proven to be valuable tools for quantification and sorting of specific subpopulations of parasite-infected red blood cells. However, identification of rare subpopulations of parasites using green fluorescent protein (GFP) labelling is complicated by autofluorescence (AF) of red blood cells and low signal from transgenic parasites. It has been suggested that cell sorting yield could be improved by using filters that precisely match the emission spectrum of GFP. Methods Detection of transgenic Plasmodium falciparum parasites expressing either tdTomato or GFP was performed using a flow cytometer with interchangeable optical filters. Parasitaemia was evaluated using different optical filters and, after optimization of optics, the GFP-expressing parasites were sorted and analysed by microscopy after cytospin preparation and by imaging cytometry. Results A new approach to evaluate filter performance in flow cytometry using two-dimensional dot blot was developed. By selecting optical filters with narrow bandpass (BP) and maximum position of filter emission close to GFP maximum emission in the FL1 channel (510/20, 512/20 and 517/20; dichroics 502LP and 466LP), AF was markedly decreased and signal-background improve dramatically. Sorting of GFP-expressing parasite populations in infected red blood cells at 90 or 95% purity with these filters resulted in 50-150% increased yield when compared to the standard filter set-up. The purity of the sorted population was confirmed using imaging cytometry and microscopy of cytospin preparations of sorted red blood cells infected with transgenic malaria parasites. Discussion Filter optimization is particularly important for applications where the FP signal and percentage of positive events are relatively low, such as analysis of parasite-infected samples with in the intention of gene-expression profiling and analysis. The approach outlined here results in substantially improved yield of GFP-expressing parasites, and requires decreased sorting time in comparison to standard methods. It is anticipated that this protocol will be useful for a wide range of applications involving rare events.

The Lewis(b) blood group antigen has been implicated as a putative receptor for Helicobacter pylori in the gastric mucosa. Furthermore, an increased prevalence of duodenal ulcer was found in non-secretors and it has been suggested that secretor status may influence bacterial colonisation density. Other investigators have hypothesised that severity of antral gastritis may be related to colonisation density of the bacterium alone, and that a critical bacterial load is necessary for the development of duodenal ulcer. Our objectives were to investigate whether a relationship existed between host Lewis and ABO blood group phenotype and prevalence of H. pylori infection. In addition we investigated whether bacterial colonisation density and the ensuing inflammatory response was influenced by secretor status and ABO blood group phenotype. The Lewis and ABO blood group phenotype of 207 patients undergoing upper endoscopy was determined. Of these, 136 were secretors and 62 were nonsecretors. Forty-five percent of patients were infected with H. pylori. No significant association was found between H. pylori infection and expression of Lewis(a) or Lewis(b) blood group antigen. The mean histological density of H. pylori was 1.8 +/- 0.2 among non-secretors and 1.51 +/- 0.13 among secretors (P = 0.209), with a mean grade of lymphocytic infiltration significantly greater in H. pylori-infected non-secretors (2.23 +/- 0.123 vs 1.8 +/- 0.074; P = 0.003). In addition, blood group O non-secretors had a significantly higher grade of lymphocyte infiltration of their gastric mucosa compared to non-O non-secretors (2.53 +/- 0.133 vs 1.93 +/- 0.181, P = 0.027). These results suggest that although no in vivo relationship exists between H. pylori and preferential adhesion to the putative Lewis(b) receptor, bacterial colonisation and the ensuing inflammatory response may be influenced at least in part by host expression of ABO and Lewisa blood group antigens.

Background: The ability to secrete blood group antigens into body fluids and secretions is controlled by a single gene on chromosome 19. By means of erythrocyte Lewis (Le) antigen phenotype secretor status can be inferred. An increase prevalence of non-secretors of blood group antigens among coeliac patients has recently been described., Methods: Blood was collected from 112 coeliac patients and 103 controls and tested for secretor status. Secretor status was correlated with human leucocyte antigens (HLA) in coeliac patients, thus evaluating a proposed interaction of susceptibility genes--that is, the secretor gene on chromosome 19 and HLA-linked genes on chromosome 6. Case notes for coeliacs were reviewed with regard to clinical outcome., Results: Of 112 coeliacs who had either Le(a) or Le(b) antigens, 36 (32%) were non-secretors Le(a+, b-), compared with 27% (28) of 103 disease-free controls (P = 0.313). Recessive Lewis phenotype Le(a-, b-) was found in 9% of coeliacs versus 2% of controls. Prevalence of HLA-A1, B8, DR3, and DQ2 was unrelated to secretor status in coeliac versus patients. An increased prevalence of complications and coeliac-associated abnormalities was found in the non-secreting and recessive coeliac groups., Conclusions: This study shows no firm relationship between the non-secretor state and coeliac disease, nor any difference in the distribution of HLA markers among secretor and non-secretor coeliacs. It is unlikely, therefore, that the secretor gene is the much sought-after second coeliac gene.

The Epstein-Barr virus has been implicated in the etiology of endemic Burkitt's lymphoma, post-transplant lymphoma, large-cell anaplastic CD30 (Ki-1)-positive lymphoma, and in many T-cell lymphomas. A recent report has found Epstein-Barr virus genome in association with 4 of 11 cases (36%) of enteropathy-associated T-cell lymphoma. In a retrospective study, we have characterized 22 consecutive cases of enteropathy-associated T-cell lymphoma from the West of Ireland where celiac disease is endemic. All cases were immunophenotyped with T- and B-cell markers including the anaplastic large-cell lymphoma marker CD30 or Ki-1. Nineteen cases were studied for latent membrane protein expression and 16 for Epstein-Barr virus small RNAs by in situ hybridization using EBER oligonucleotides on routinely processed sections. Only 1 of 16 cases (6%) showed Epstein-Barr virus in tumor cells and no cases stained with latent membrane protein. Eight of 22 cases (36%) including the EBER-positive case were positive for CD30. These results suggest that the Epstein-Barr virus does not commonly play a role in the pathogenesis of enteropathy-associated T-cell lymphoma from this area.

Celiac sprue (CS) is frequently complicated by malignancy, most commonly small intestinal lymphoma. Our study was performed in an area with a high prevalence of CS to define the clinical features, response to treatment, and outcome of this tumor. Of a total of 31 lymphomas complicating CS identified, 30 case records and 24 tumor specimens were reviewed. Overall 1-year survival was 9 of 29 (31%) and 5-year survival 3 of 27 (11%). Seven previously diagnosed celiac patients developed lymphoma; length on gluten-free diet ranged from 12 to 252 months (median 44 months). In this group, presentation was nonspecific, diagnosis difficult, and survival poor (lymphoma diagnosed in life in four of seven, mean survival 2.25 months). Twenty-three patients had CS and lymphoma diagnosed during the same illness. In this group, 14 of 23 presented with a surgical emergency and were treated with tumor resection and chemotherapy. Nine are disease-free and alive or died of another cause after 10-196 months (mean 74 follow-up). Celiac-associated lymphoma is a frequent, difficult to diagnose, and commonly fatal complication of CS. An aggressive diagnostic approach, including laparoscopy, is recommended. Long-term survival can be expected in a significant number of these patients and in our series was almost exclusively confined to those treated with chemotherapy.

Objective: To demonstrate the potential and effectiveness of autologous blood transfusion in an obstetric and gynaecological practice., Setting: The Department of Obstetrics and Gynaecology and the department of Haematology, University College Hospital, Galway, Ireland., Subjects: One hundred and sixty-eight women undergoing abdominal hysterectomy, 42 women undergoing repair procedures, and 56 women undergoing elective caesarian sections participated in this programme., Results: In the abdominal hysterectomy group 329 units of blood were collected of which 48% were transfused to the donors. In the repair group 82 units of blood were collected of which 21.9% were transfused to the donors. In the elective caesarian section group 105 units of blood were collected of which 64.7% were transfused to the donors. Overall the donation procedure was well tolerated with infrequent donor reactions., Conclusion: Our experience demonstrates that autologous blood transfusion is a safe and reasonable transfusion practice in the setting of obstetrics and gynaecology.

Variations in the centrifugal force (g) used to prepare platelet-rich-plasma (PRP) alter not only the number of platelets therein but also their size and reactivity. Anticoagulants also affect these parameters. According we suggest that PRP preparations need to be strictly standardised. Critical comment on the use of the platelet aggregation model as a means of assessing 5-hydroxytryptamine receptor function is included.

'Pitted' erythrocyte counts are widely used in the quantitative assessment of functional hyposplenism and in the prediction of recurrence of splenic function in splenectomized subjects. Both of these functions require counts from electively splenectomized controls for comparison. The 'pitted' erythrocyte counts in patients splenectomized for congenital spherocytosis are lower than those found in subjects whose spleens were removed electively for other reasons. This appears to be due to the specific membrane defect which impairs the formation of the vacuoles which are responsible for the appearance of 'pitted' erythrocytes under the interference-phase microscope.

Babesiosis is a tick-borne protozoan disease which principally affects animals but occasionally affects humans. Cases have been reported from many parts of Europe with no evidence of case-clustering. We report the second case of babesiosis from a small area in the west of Ireland.

Platelet count and volume were measured in 84 splenectomised subjects, 142 patients with coeliac disease and 77 healthy subjects. An inverse, non-linear correlation between platelet count and volume was found in healthy subjects and coeliac patients, but was not present in splenectomised subjects who had higher platelet counts (P = 0.0001) and mean platelet volumes (P = 0.0001) than healthy subjects. Platelet counts correlated with splenic function in patients with coeliac disease and were higher in patients with severe hyposplenism than in normosplenic coeliacs (P = 0.0001). Splenic function did not influence the mean platelet volume (MPV) in coeliac disease but normosplenic coeliacs had higher MPV than normal subjects (P = 0.05). Serum iron and red cell folate were not correlated to MPV in coeliac disease. We conclude that splenic function effects platelet count and volume in non-coeliac subjects and platelet count in coeliac disease. However, other unidentified factor(s) influence the MPV in coeliac disease.

The iron status of four hundred and forty-seven hospital patients was studied in order to assess the efficiency of laboratory tests in diagnosing iron deficiency. One hundred and three patients (23%) were iron deficient on bone marrow examination. The laboratory tests had a low diagnostic efficiency, with either a low diagnostic rate or a high false positive rate. However, serum ferritin, despite a diagnostic rate of 25% did establish the diagnosis with near certainty, avoiding the need for invasive and costly investigations. Serum ferritin should be retained in the laboratory investigation of iron deficiency. Serum iron with iron binding capacity should be removed from the repertoir.

Hereditary haemolytic anaemia with basophilic stippling caused by pyrimidine 5'-nucleotidase deficiency is described in three members of two unrelated Irish families. In one family, the disease was moderately severe and the patient's condition was improved by splenectomy. In the other family the haemolytic anaemia was well compensated. In neither family was there a marked elevation of reduced glutathione. The implications are that pyrimidine 5'-nucleotidase deficiency is a heterogeneous disorder, both clinically and biochemically. In more severe forms splenectomy may be beneficial.