Analysis of a panel of antibodies to APC reveals consistent activity towards an unidentified protein.

Acquisition of truncating mutations in the adenomatous polyposis coli (APC) protein underlies the progression of the majority of sporadic and familial colorectal cancers. As such, the localisation patterns and interacting partners of APC have been extensively studied in a range of systems, relying on the use of a broad panel of antibodies. Until recently, antibodies to APC have been used largely unchecked. However, several recent reports have been invaluable in clarifying the use of a number of antibodies commonly used to detect APC. Here, we analyse the specificity of a further subset of antibodies to APC. We used a panel of six commercially available antibodies (directed to the amino and carboxy termini of APC) and confirm the detection of full-length APC by immunoblotting. We demonstrate that a 150 kDa protein, also reproducibly detected by this panel of antibodies, is unlikely to be APC. We present data for the immunological staining patterns of the APC antibodies and validate the results through RNAi. Using this approach, we confirm that the apical staining pattern, observed by immunofluorescence and previously reported in cell systems, is unlikely to be APC. Finally, we present our data as a summary of APC-antibody specificities for APC.

Cytogenetics, molecular and ultrastructural characteristics of biphenotypic acute leukemia identified by the EGIL scoring system.

Biphenotypic acute leukemia (BAL) is a rare, difficult to diagnose entity. Its identification is important for risk stratification in acute leukemia (AL). The scoring proposal of the European Group for the Classification of Acute Leukemia (EGIL) is useful for this purpose, but its performance against objective benchmarks is unclear. Using the EGIL system, we identified 23 (3.4%) BAL from among 676 newly diagnosed AL patients. Mixed, small and large blast cells predominated, with FAB M2 and L1 constituting the majority. All patients were positive for myeloid (M) markers and either B cell (B) (17 or 74%) or T cell (T) (8 or 34%) markers with two exceptional patients demonstrating trilineage phenotype. Six (50%) of studied M-B cases were positive for both IGH and TCR. In six (26%) patients myeloid lineage commitment was also demonstrable by electron cytochemistry. Abnormal findings were present in 19 (83%) patients by cytogenetics/FISH/molecular analysis as follows: t(9;22) (17%); MLL gene rearrangement (26%); deletion(6q) (13%); 12p11.2 (9%); numerical abnormalities (13%), and three (13%) new, previously unreported translocations t(X;6)(p22.3;q21); t(2;6)(q37;p21.3); and t(8;14)(p21;q32). In conclusion, the EGIL criteria for BAL appear robust when compared against molecular techniques that, if applied routinely, could aid in detecting BAL and help in risk stratification.

Correlation of antigenic expression with progress in antibiotic therapy of acute human brucellosis.

Human brucellosis is a zoonotic disease which is endemic in Saudi Arabia. The aim of this study was to investigate the humoral immune responses and identify the target antigens that persist at different stages in human brucellosis during antibiotic therapy. To do this, an acute case of accidental nosocomial infection was studied experimentally. Blood was collected from the patient at the time of diagnosis, and at weekly intervals during therapy until remission. IgG and IgM immunoblotting was used to characterize specific antigenic determinants, and ELISA antibody titration was performed to quantify the circulating antibodies. Results indicated that protein bands of 12-13.5 kDa bound IgG in the patient's sera but did not bind IgM on immunoblots and are probably not specific for, or important in, early stage infections. However, an 18 kDa band persisted during infection through remission. The pivotal and most important findings were that the number of protein bands seen on immunoblots, the magnitude of ELISA antibody titres and the concomitant changes in the intensity of the polypeptide bands of 42-43 kDa were positively correlated with the stage of infection. High numbers of anti-IgG and -IgM immunoblot bands coupled with high ELISA antibody titres and a concomitant increase in intensity of the 42-43 kDa bands were positively correlated with acute and severe infection. Conversely, a reduction in the number of polypeptide bands as well as a decrease in the intensity, until the complete disappearance of the 42-43 kDa bands, coupled with low (baseline) ELISA antibody titration values indicated successful treatment and remission. The routine use of the methods described here to ascertain the stage of the disease, assess the progress of antimicrobial therapy and monitor cases of relapse in human brucellosis is suggested.

The development of two flanking SCAR markers linked to a sex determination locus in Salix viminalis L.

Most studies of sex determination systems in plants involve dioecious annuals that have known sex chromosomes. Despite the absence of such structures in the majority of dioecious plants, gender seems to be under relatively strict genetic control in some species. Genetic markers linked to a female sex-determination locus in Salix viminalis L. have been discovered through bulked segregant analysis of three full-sib families using approximately 1,000 arbitrary primers. Two RAPD markers that were present in the common female parent as well as in predominantly female progeny of these families were subsequently sequenced and converted to sequence characterized amplified region (SCAR) markers. The two SCAR markers are correlated with gender in the three full-sib families and are present in 96.4% of the female progeny and 2.2% of the males, providing evidence of linkage to a putative female-specific locus associated with gender determination in S. viminalis. Estimates of recombination suggest that the two markers are flanking a putative sex determination locus, SDL-II, in certain families of S. viminalis.

Interaction between Ku80 protein and a widely used antibody to adenomatous polyposis coli.

The adenomatous polyposis coli (APC) gene and its expressed product are highly studied because of its role as a tumour-suppressor protein. Inherited mutations in APC lead to the condition known as familial adenomatous polyposis (FAP), which predisposes the affected individuals to colorectal cancer. Furthermore, mutations in APC are found in the majority of sporadic cases of colon cancer. There have been many published studies concerning the cellular localisation of APC, this being fundamental to our understanding of its function, but there has also been much concern over the specificity of certain commercially available antibodies to APC. Here we report that the widely used antibody APC(N15) demonstrates a strong interaction with the Ku80 subunit of the Ku heterodimer under defined experimental conditions. Based on the data presented here, we suggest that APC(N15) is not suitable for many applications used for the study of APC.

Use of nucleic acid testing for blood donor screening of human immunodeficiency virus and hepatitis C virus in the Saudi population.

OBJECTIVE: To determine the risk of transfusion associated infection for human immunodeficiency virus and Hepatitis C virus using nucleic acid testing. METHODS: During March 1998, 400 donor blood samples from the Saudi population that were negative by serology were further tested for human immunodeficiency virus 1 and 2 and Hepatitis C virus using nucleic acid testing. RESULTS: A total of 400 were tested by nucleic acid testing, 381 of these were negative, 4 were indeterminate but were found to be negative on repeat testing and one seronegative sample was found to be positive for Hepatitis C virus. CONCLUSION: Due to the low prevalence of human immuno-deficiency virus in the Kingdom of Saudi Arabia, nucleic acid testing of blood donors by serology is adequate for screening. But the higher prevalence of Hepatitis C virus and increased risk of transmission would indicate that nucleic acid testing may be warranted for Hepatitis C virus in the near future.

Fibrinolysis in pseudotumor cerebri.

Pseudotumor cerebri is a syndrome associated with diverse putative etiological factors that include chemicals such as vitamin A, tetracycline and estrogens or venous circulatory disturbances like sagittal or transverse sinus thrombosis. Diseases predisposing to thrombosis, such as polycythemia vera and essential thrombocythemia, were reported to cause sinus thrombosis and pseudotumor cerebri. This is a pilot study to investigate the possible role of hemostatic factors in the pathogenesis of pseudotumor cerebri. We studied nine patients with severe, recurrent, or refractory pseudotumor cerebri causing visual impairment and found abnormal euglobulin clot lysis time (prestress in all of them and post stress in seven). Digital subtraction angiography was suggestive of recanalized sinus thrombosis in only three patients. We conclude that abnormalities in the fibrinolytic system are present in a subset of patients with severe pseudotumor cerebri, which calls for further studies on venous circulatory pathogenesis of pseudotumor cerebri and the possible role of anticoagulants in such cases.

Morphologic immunophenotypic and cytogenetic patterns of adult acute myeloid leukemia in Saudi Arabia.

During a 6-year period we received bone marrow (BM) and peripheral blood (PB) samples from 178 patients with acute myeloid leukemia (AML). All patient BM, and occasionally, PB samples were characterized according to FAB criteria, and by immunophenotyping (IP) and cytogenetics (CG). This report summarizes the findings in the 125 patients who were older than 15 years. Their mean and median ages were 39.4 and 37.0 years. There were 8 (6.4%) M1, 27 (21.6%) M2, 15 (12.0%) M3, 49 (39.2%) M4, 14 (11.2%) M5A, 9 (7.2%) M5B and 2 (1.6%) M6. IP showed that HLA-DR was most strongly and frequently expressed by M1 blasts (53.5%, 86%) and least strongly and frequently expressed by M3 blasts (4.5%, 0%). HLA-DR was also relatively strongly expressed by M4, M5A, M5B (21.5%, 43%; 34.9%, 69%; and 19.2%, 56%, respectively). CD11b was uniformly weakly expressed by all FAB subgroups. CD13 was most strongly and frequently expressed by M4 (20%, 43%), and was relatively weakly and infrequently expressed by the other FAB subtypes (9.5%, 9.2%, 16.4%, 8.4%, 16.3%). CD14 was moderately expressed by M4 (15.2%, 25%) and M5B (14.0%, 22%) and M1 (7.0%, 40%). CD33 was most strongly expressed by M3 blasts (26.3% and 61%), and was most weakly expressed by M5B (10.6% and 22%). Fourteen (11.2%) patients had blasts that showed lymphoid antigens (5 T, 5 B, 5 CALLA) in addition to myeloid characteristics. Fifty-four (51.9%) of 104 patients tested had one or more karyotypic abnormalities, the most frequent of which was 8+. Only the t(15:17) was specific, and was seen in M3. Four patients with anomalous IP had trisomy 21, one of whom also had 11q-. We conclude that Saudi Arabian AML shows FAB patterns similar to patients in the West, and that M3 patients have a characteristic IP and cytogenetic pattern. Apart from this the MIC classification failed to reveal characteristic modes.

Two different forms of homozygous sickle cell disease occur in Saudi Arabia.

Haematological, clinical and some molecular genetic features of homozygous sickle cell (SS) disease in Saudi Arabia have been compared in 33 patients from the Eastern Province (Eastern) and 30 from the South Western Province (Western). Eastern patients all had the Asian beta globin haplotype whereas Western patients were more variable but predominantly of the Benin haplotype. Eastern patients had more deletional alpha thalassaemia, higher total haemoglobin and fetal haemoglobin levels, and lower HbA2, mean cell volume, reticulocytes, and platelet counts. Clinically, Eastern patients had a greater persistence of splenomegaly, a more normal body build and greater subscapular skin fold thickness, and Western patients had more dactylitis and acute chest syndrome. Painful crises and avascular necrosis of the femoral head were common and occurred equally in both groups. The disease in the Eastern province has many mild features consistent with the higher HbF levels and more frequent alpha thalassaemia but bone pathology (painful crises, avascular necrosis of the femoral head, osteomyelitis) remains common. The disease in the West is more severe consistent with the Benin haplotype suggesting an African origin.

Morphological and immunological pattern of blastic transformation in chronic myeloid leukemia in Saudi Arabia: Study of 90 transformations among 248 patients.

We examined the pattern of blastic transformation in 90 of 248 patients (36%) with chronic myeloid leukemia who were seen at the King Faisal Specialist Hospital and Research Centre between 1975 and 1988. The mean and median ages of all patients were 38.2 and 36.0 years, respectively. Four of the 90 transformants (4.4%) presented in blastic transformation, and 86 cases (95.5%) evolved from a well-defined chronic phase. Twenty-nine (32.2%) of the patients underwent lymphoid blastic transformation, while 28 (31.1%) were myeloid, seven (7.8%) were myelomonocytic, four (4.4%) were monocytic or erythroblastic, six (6.7%) were megakaryoblastic, ten (11.1%) were of mixed lineage, and two (2.2%) were unclassifiable. The lymphoid blast cells were uniformly common acute lymphocytic leukemia (i.e., Ia and CD10 positive), whereas the myeloid transformations were predominantly Ia negative. Mixed phenotype blasts were also predominantly Ia positive (i.e., 8 of 10), with varying positively for CD10 and myeloid/monocyctic markers. We conclude that blast crisis in chronic myeloid leukemia occurs in Saudi patients in a pattern similar to that seen in patients elsewhere, and that surface Ia antigen positivity in lymphoblast cells is a reliable marker for differentiating lymphoid from nonlymphoid crisis, in which the Ia antigen is not usually demonstrable.

Ultrasound guided therapeutic catheters: recent developments and clinical results.

The increasing use of intravascular ultrasound technology by clinicians is providing detailed and immediate information about the results of interventions, and this is stimulating the development of new catheters that use ultrasound imaging to control therapy in real time. Cold and thermal balloon angioplasty, atherectomy, embolectomy, laser ablation and rotational recanalization are a few of the interesting capabilities now being added to ultrasound catheters. We report on the development and characteristics of some of these devices and attempt to assess their potential to precisely direct therapy.

Immunophenotypic and age patterns of childhood acute lymphoblastic leukemia in Saudi Arabia.

Acute lymphoblastic leukemia (ALL) is the most common malignancy of childhood in the West, characteristically showing a peak incidence in children aged between two and five years, and being predominantly of the common ALL (cALL) phenotype. In this article, we examine the hypotheses that ALL is relatively less common among childhood malignancies in Saudi Arabia; that the cALL phenotype is uncommon; that T cell ALL (TALL) is relatively more common. We report that of 163 children with ALL seen at the King Faisal Specialist Hospital and Research Centre, we find that their median age was 5.0 years with a modal value of 3 years, with a range of 4 months to 14 years; that there were 93 cALL patients who were predominantly young (median age 5.0 years). There were 20 (12.3%) patients with TALL, whose median age was 8.5 years, 35 (21.5%) patients who were null cell ALL and whose median age was 6.0 years, 14 (8.6%) patients with B cell ALL whose median age was 9.0 years, and 3 (1.8%) patients with mixed phenotype ALL. We also identify a group of 6 (3.7%) patients whose blasts were CD10 negative and showed B cell differentiation without surface membrane immunoglobulin. We conclude that age and phenotypic characteristics of ALL patients are mainly similar to ALL in the West but that L3 was much more common. A small group of six patients showed unusual B cell phenotype and require further evaluation and analysis.

Lineage ambiguity in acute leukemia.

Two cases of acute nonlymphocytic leukemia that showed surface phenotypes characteristic of lymphoid cells are reported. The cases, both involving female patients were studied by a variety of methods including flow cytometry and karyotyping. In Case 1, the patient, a 10-year-old girl, had poorly differentiated myeloblasts (FAB M1), which were weakly positive for Sudan black B (SBB), but negative for alpha naphthyl acetate esterase (NAE) and naphthol ASD chloroacetate esterase (CAE). Myeloperoxidase was demonstrated ultrastructurally in some of the blasts. In Case 2, the 30-year-old patient had typical myelomonocytic leukemia (FAB M4), with SBB-, NAE-, and CAE-positive blasts. Both cases were negative for terminal deoxynucleotidyl transferase. Case 1 was negative for myeloid membrane markers, whereas Case 2 was strongly positive for My7 and My9. Surprisingly, both cases showed significant positivity for B-cell restricted antigens B1, B2, and B4. These findings suggest ambiguous or dual lineage, supporting the concepts that some leukemias could arise from a pluripotent hematopoietic progenitor cell (Case 1) or from cells that though differentiated in some respects, could still preserve some early antigens (Case 2).

Acquired immune deficiency syndrome in the Middle East from imported blood.

In Saudi Arabia, a native patient with no known risk factors for the acquired immune deficiency syndrome (AIDS) developed both clinical and laboratory evidence of AIDS 2 years after receiving transfusion of 11 units of blood obtained from a commercial distributor in the United States. This case suggests that a history of transfusions of blood components imported from areas where AIDS is prevalent should be elicited from patients in the Middle East with symptoms and physical findings suggesting AIDS.

Red blood cell distribution width index in some hematologic diseases.

The red blood cell distribution width index (RDW) was determined in a group of anemic male patients and normal male blood donors. Elevated mean RDW values were found in the anemic patients, with the highest value seen in sickle cell anemia, sickle cell-beta thalassemia, sickle cell trait, beta-thalassemia trait, and iron deficiency in decreasing order of magnitude. The mean RDW of the normal male subjects was 11.3. It was found that the RDW was proportional to the reticulocyte count, with the highest values in the patients with the highest reticulocyte count (sickle cell anemia). One clinical value of the RDW therefore may lie in its capacity for reflecting active erythropoiesis. For example, patients with normal or near-normal hemoglobin and with high RDWs may be suspected of having an elevated reticulocyte count that may indicate a hemoglobinopathy, such as sickle cell trait or thalassemia trait.

Hemotherapy in open heart surgery.

The clinical charts and transfusion records of 216 patients who underwent open heart surgery with cardiopulmonary bypass between August 1983 and July 1684 were reviewed. The patients were categorized into five groups according to their operative procedures. Findings from preoperative hemostatic function tests in all groups were normal. Heparin rebound was observed in all groups, probably due to underneutralization by protamine. The results suggest that the neutralization dose of protamine per milligram of heparin should be increased to a range of between 1.5 and 1.7 mg in the post-cardiopulmonary bypass period. This should also reduce the need for fresh frozen plasma. Non-blood priming of the pump for adults and acceptance of a degree of thrombocytopenia (in the range of 60 to 80 x 10(9)/L) after cardio-pulmonary bypass will lower the blood component usage. A preoperative blood order schedule for patients with open heart surgery/cardiopulmonary bypass has been suggested.