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Background: Vascular phenotype by assessing carotid-femoral pulse wave velocity (cf-PWV) and central SBP (cSP) in the young could be used as an intermediate cardiovascular outcome measure. Tonometry is considered the gold-standard technique, but its use is challenging in clinical practice, especially when used in children. The purpose of this study was to validate cf-PWV and cSP assessment with novel oscillometric device (SphygmoCor XCEL) in children and adolescents., Methods: cf-PWV and cSP were measured in 72 children and adolescents aged 6-20 years. Measurements were performed by applanation tonometry and by the SphygmoCor XCEL device at the same visit under standardized conditions. Regression analysis and Bland-Altman plots were used for comparison of the tonometer-based with oscillometric-based method., Results: Mean cf-PWV measured by applanation tonometry was 4.85 ± 0.81 m/s and measured by SpygmoCor XCEL was 4.75 ± 0.81 m/s. The mean difference between the two devices was 0.09 ± 0.47 m/s (P = NS). cSP measured by SpygmoCor XCEL was strongly correlated with cSP measured by applanation tonometry (R = 0.87, P < 0.001). Mean cSP measured by applanation tonometry was 103.23 ± 9.43 mmHg and measured by SpygmoCor XCEL was 103.54 ± 8.87 mmHg. The mean cSP difference between the two devices was -0.30 ± 3.34 mmHg (P = NS), and fulfilled the AAMI criterion 1. The estimated intersubject variability was 2.17 mmHg., Conclusion: The new oscillometric SphygmoCor XCEL device provides equivalent results for cf-PWV and cSP values to those obtained by tonometry in children and adolescents. Thus, the SphygmoCor XCEL device could be appropriate for assessing cf-PWV and cSP in the pediatric population.

Integrin-linked kinase (ILK), PINCH and Parvin proteins form the IPP-complex that has been established as a core component of the integrin-actin link. Our recent genetic studies on Drosophila parvin, reveal that loss of function mutant defects phenocopy those observed upon loss of ILK or PINCH in the muscle and the wing, strengthening the notion that these proteins function together in the organism. Our work identified that ILK is necessary and sufficient for parvin subcellular localization, corroborating previous data indicating a direct association between these two proteins. Further genetic epistasis analysis of the IPP-complex assembly at integrin adhesion sites reveals that depending on the cell context each component is required differently. At the muscle attachment sites of the embryo, ILK is placed upstream in the hierarchy of genetic interactions required for the IPP-complex assembly. By contrast, in the wing epithelium the three proteins are mutually interdependent. Finally, we uncovered a novel property for the CH1-domain of parvin: its recruitment at the integrin-containing junctions in an ILK-dependent manner. Apparently, this ability of the CH1-domain is controlled by the inter-CH linker region. Thus, an intramolecular interaction within parvin could serve as a putative regulatory mechanism controlling the ILK-Parvin interaction.

There are limited reports of young patients with multiple myeloma (MM) who presented with multiple lytic bone lesions but without intervening infiltration of bone marrow, a pattern consisting of macrofocal MM. In order to clearly define the clinical and laboratory features and outcome of such patients, a retrospective analysis was performed of symptomatic patients with MM

Rituximab is an active agent for the treatment of Waldenstrom's macroglobulinemia. However, many patients do not respond to this agent and several others develop secondary resistance. In order to identify clinical and laboratory parameters that could predict a higher likelihood for response, we evaluated 54 patients who were treated with single-agent rituximab. Twenty-four patients (44%)exhibited > or = 50% reduction of serum monoclonal protein. Previously untreated and pretreated patients had the same probability for response. Low response rates were noted in patients with serum monoclonal protein level > or = 40 g/L (17%) and serum albumin level < 35 g/L (14%). Furthermore, a multivariate analysis indicated that high serum monoclonal protein and low albumin were the dominant variables associated with shorter time to progression. The presence of 2, 1, or none of these variables was associated with median times to progression of 4 months, 11 months, and approximately 48 months, respectively. We conclude that patients with low levels of monoclonal protein and normal albumin are the best candidates for treatment with rituximab.

Recent data have suggested that rituximab is an active agent for the treatment of Waldenstrom's macroglobulinemia (WM). However, the patients that are more likely to benefit have not been clearly defined. In order to address this question we evaluated 52 patients who were treated with single-agent rituximab in the context of prospective studies. Several clinical and laboratory variables were assessed for their correlation with response and time to progression. Twenty-three (44%) patients achieved a partial response after treatment with rituximab. Previously untreated and pretreated patients had the same probability for response. Higher response rates were noted in patients with serum monoclonal protein < 40 g/l, with serum albumin > or = 35 g/l and with kappa light chain. The median time to progression for all patients was 13.8 months. A multivariate analysis indicated that elevated serum monoclonal protein levels and low serum albumin were the dominant variables associated with shorter progression. Presence of two, one or none of these adverse prognostic factors was associated with time to progression of 3.6 months, 11 months and more than 40 months, respectively. We conclude that rituximab is an effective treatment modality for patients with WM. Patients with both low levels of monoclonal protein and normal albumin are the best candidates for treatment with standard dose rituximab.

Purpose: Waldenström's macroglobulinemia (WM) is a low-grade lymphoplasmacytic lymphoma in which CD20 is usually expressed on tumor cells. There is evidence that patients with WM may benefit from treatment with the anti-CD20 monoclonal antibody rituximab. We performed a prospective phase II study to clearly define the activity of rituximab in patients with this disease., Patients and Methods: Twenty-seven patients with WM were treated with rituximab 375 mg/m(2) intravenously (IV) for 4 weeks. Three months after completion of rituximab, patients without evidence of progressive disease received repeat 4-week courses of this agent. All patients were symptomatic, their median age was 72 years, and 15 patients were previously untreated., Results: Twelve patients (44%; 95% confidence interval, 25.5% to 64.7%) achieved a partial response after treatment with rituximab. Median time to response was 3.3 months (range, 2.2 to 7.1 months). Responses occurred in six (40%) of 15 previously untreated patients and in six (50%) of 12 pretreated patients. Patients with a serum immunoglobulin M less than 40 g/L had a significantly higher response rate. The median time to progression for all patients was 16 months, and with a median follow-up of 15.7 months, nine of 12 responding patients remain free of progression. Treatment with rituximab was well tolerated, with approximately one fourth of patients experiencing some mild form of infusion-related toxicity, usually fever and chills., Conclusion: Our prospective data indicate that rituximab is well tolerated and active in patients with WM. Previously untreated and pretreated patients seem to benefit equally. Repeat 4-week courses of rituximab may prolong the duration of response of the disease, but this observation requires confirmation in prospective, randomized trials. Furthermore, studies that will combine rituximab with chemotherapy may be relevant.

We report two patients with severe thrombocytopenia and life-threatening bleeding that were successfully managed with recombinant activated factor VII (rFVIIa). The first was a 75-year-old male with Waldenström's macroglobulinemia. During a therapeutic course with fludarabine, he developed severe autoimmune thrombocytopenia resistant to conventional treatment, followed by persistent uncontrollable nasal bleeding. Platelet transfusions failed to increase the platelet count and control the hemorrhage. When hemoglobin levels fell below 8.5 g/dL and the patient's clinical condition got much worse, a single dose of 4.8 mg rFVIIa (90 microg/kg) was given as an i.v. bolus. Ten minutes after the rFVIIa injection, nasal bleeding stopped, the patient's clinical condition progressively improved, and splenectomy could be carried out uneventfully 2 days later. The second patient, a 52-year-old female, was under treatment for pre-B lymphoblastic leukemia. She developed severe thrombocytopenia, secondary to chemotherapy, complicated by massive gastrointestinal bleeding. Despite intensive treatment with platelet transfusions, hemorrhage continued and her condition deteriorated rapidly. She was then given an i.v. bolus injection of 4.8 mg rFVIIa, which resulted in cessation of hemorrhage and dramatic improvement of her clinical status. No adverse effects from the treatment with rFVIIa were observed. In conclusion, rFVIIa appears to be an attractive alternative for controlling hemorrhage in patients with severe thrombocytopenia, especially when platelet transfusions are unavailable or ineffective.

Integrin-linked kinase (ILK) was identified by its interaction with the cytoplasmic tail of human beta1 integrin and previous data suggest that ILK is a component of diverse signaling pathways, including integrin, Wnt, and protein kinase B. Here we show that the absence of ILK function in Drosophila causes defects similar to loss of integrin adhesion, but not similar to loss of these signaling pathways. ILK mutations cause embryonic lethality and defects in muscle attachment, and clones of cells lacking ILK in the adult wing fail to adhere, forming wing blisters. Consistent with this, an ILK-green fluorescent protein fusion protein colocalizes with the position-specific integrins at sites of integrin function: muscle attachment sites and the basal junctions of the wing epithelium. Surprisingly, mutations in the kinase domain shown to inactivate the kinase activity of human ILK do not show any phenotype in Drosophila, suggesting a kinase-independent function for ILK. The muscle detachment in ILK mutants is associated with detachment of the actin filaments from the muscle ends, unlike integrin mutants, in which the primary defect is detachment of the plasma membrane from the extracellular matrix. Our data suggest that ILK is a component of the structure linking the cytoskeleton and the plasma membrane at sites of integrin-mediated adhesion.

We report results from a systematic study to identify the molecular basis of glucose-6-phosphate dehydrogenase (G6PD) deficiency on a sample of 299 male subjects from the Hellenic population. Our stepwise approach involved partial biochemical characterization and quantitation of the enzyme's activity, MboII restriction endonuclease digestion to identify the G6PD Mediterranean variant, which represents the most frequent G6PD variant in our population and a nonradioactive polymerase chain reaction-single-strand conformation polymorphism methodology for the detection of the underlying molecular defect(s) in the rest of the non-Mediterranean G6PD-deficient individuals. Through this approach, six different G6PD variants were identified (G6PD Mediterranean, G6PD Hermoupolis, G6PD Cassano, G6PD Seattle, G6PD Ierapetra and G6PD Acrokorinthos), two of which were new (G6PD Hermoupolis, G6PD Acrokorinthos). In essence, this study underlines the remarkable genetic heterogeneity of the G6PD deficiency in the Hellenic population, while the finding of the double mutant, G6PD Hermoupolis, may help to outline the relationship and evolution of mutations in the human G6PD locus., (Copyright 2000 S. Karger AG, Basel)

Background and Objective: Excessive hemosiderosis is the main reason for the multi-organ failure observed in multitransfused patients. Deferiprone (1,2-dimethyl-3-hydroxy-pyridine-4-one, L1) is an orally active iron chelator mainly excreted via urine. We conducted a study in order to determine the efficacy and safety of L1 in Greek thalassemic patients., Design and Methods: A group of 11 thalassaemic patients entered the study; L1, the Cipla formulation for deferiprone, at a daily dose of 75-100 mg/kg bw t.i.d. was used. After giving informed consent all patients were subjected to clinical examination and biological tests., Results: All patients tolerated the L1 well; there were no significant side effects (except for slight gastrointestinal disturbances for the first days). The net urinary iron excretion ranged from 6.96 to 26.1 mg/24h. Serum ferritin declined within 4-6 months in most of the patients., Interpretation and Conclusions: The results suggest that L1 is a rather safe drug which decreases iron overload without causing any considerable side-effects in Greek thalassemics.

The purpose of the study was to detect cases of Sjögren's syndrome among newly diagnosed untreated patients with non-Hodgkin's lymphoma and, furthermore, to identify in such cases clinical and serologic features known to occur more frequently in Sjögren's syndrome patients who evolve into lymphoma. Accordingly, thirty-three cases of newly diagnosed non-Hodgkin's lymphoma, prior to any treatment administration, were thoroughly studied for evidence of Sjögren's syndrome. Immunophenotyping for T and B cells and kappa and lambda light chains was concomitantly performed on both lymphomatous tissues and minor salivary glands. There were 5 patients with T cell and 28 with B cell lymphoma of various histologic subtypes and grades. Two of the latter (7.1%) had a positive for Sjögren's syndrome minor labial salivary gland biopsy, positive responses to the specific questionnaires for both eye and mouth dryness and abnormal Schirmer's and rose Bengal eye tests, substantiating the diagnosis of Sjögren's syndrome. Both were male with lung and stomach non-Hodgkin's lymphoma respectively, enlargement of the lacrimal glands, monoclonal gammapathy of the IgM kappa type and, one of them had high titer and of fine speckled pattern positive antinuclear antibodies and anti-Ro(SSA) and anti-La(SSB) antibodies in his serum. A monotypic infiltrate with kappa light chain restriction, identical to that in the lymphomatous tissue of these two patients, was present in their minor salivary gland biopsy as well. Such a finding was not encountered in any of the remaining patients. Although our sample is relatively small, our results confirm the relationship between Sjögren's syndrome and non-Hodgkin's lymphoma, looked at from the opposite direction. Obviously, studies involving larger populations would be more definitive, regarding the issue of what percentage of this lymphoma patients originates from Sjögren's syndrome.

Bacterial lipopolysaccharide (LPS) attachment at the hemocyte surface is based on the crosslinking of surface associated p47 to LPS, via the intermediacy of tyrosine derivatives generated by the action of phenoloxidase (PO). This attachment is an initial step for LPS internalization from hemocytes (Charalambidis et al., 1996). The results presented clearly show the critical role of hemocyte associated PO activity in the above processes. Biochemical and immunofluorescent analysis demonstrated unambiguously the presence of prophenoloxidase (proPO) on the hemocyte surface. The cell-surface expression of proPO appeared to be LPS-independent, whereas its activation was LPS-dependent. The activation of cell surface proPO involves a limited proteolysis, since upon activation with chymotrypsin proPO is converted to a set of smaller molecular weight proteins with PO activity. The activation appears to be due to enzyme activators, serine proteases, released upon LPS-stimulation. This hypothesis was supported from the activation of membrane proPO by the culture medium of hemocytes which have been triggered with LPS. In addition, proPO, activation was abolished by inhibitors of secretion and PMSF. The release of proPO activators upon LPS-stimulation is mediated via protein tyrosine phosphorylation, as genistein inhibited proPO activation, a situation similar to that reported by us for the release of the effector protein p47 (Charalambidis et al., 1995). The LPS-stimulated activation of cell-surface proPO is a prerequisite for LPS (either cell associated or cell free) internalization, as judged by the resistance of LPS binding to dissociation by proteinase K.

sIL-6R is a 55 kD soluble molecule mediating the interleukin-6 (IL-6) signal through the IL-6 receptor-associated transmembrane signal transducer, gp130. It has recently been suggested that sIL-6R serum levels may reflect disease severity in multiple myeloma (MM). We determined sIL-6R serum levels in 25 normal controls (NC) and in 80 MM patients at diagnosis and during the course of the disease. Measurements were done by ELISA. In NC, sIL-6R levels ranged from 14 to 40 ng/ml (median 28 ng/ml) whereas in MM patients the range was 10-200 ng/ml (median 38 ng/ml) (P<0.01). 61 patients entered remission and 19 were resistant. Median sIL-6R value at diagnosis was 36 ng/ml (10-120) in responding patients, and 82 ng/ml (20-200) in non-responding patients (P<0.001). During a follow-up from 12 to 89 months, sIL-6R values remained more or less stable in most patients. High sIL-6R levels correlated with poor survival.

It is well known that activated prophenoloxidase (proPO) plays an important role in cuticular melanization and sclerotization. In addition, studies dealing with immune response of insects suggest that phenoloxidase (PO) is also critical in the defense reactions of insects against invaders. proPO is activated by elicitors derived from microbial cell wall components such as peptidoglycan, beta-1,3-glucan, and lipopolysaccharide (LPS). According to our recent studies we proposed a model clarifying the role of PO in both cellular and humoral immune responses. LPS triggers Ceratitis capitata hemocytes via induced protein tyrosine phosphorylation to release biologically active molecules, including p47 and proPO-activators. Furthermore, hemocytes in response to LPS facilitate clearance of LPS from the hemocoel of medfly. The effector molecules involved in the LPS clearance are hemocyte surface-associated p47 (mp47), soluble p47 (sp47), activated proPO, and tyrosine. A similar LPS clearance system in the integument of medfly in vitro was also demonstrated. According to our data, the proposed mechanism for LPS clearance from hemocoel and from integument is the crosslinking of LPS to p47 or certain integumental proteins via the intermediacy of reactive tyrosine derivatives generated by PO activity, as is the case for cuticular protein-chitin crosslinks during sclerotization. We also demonstrated that metabolites of the eumelanin biosynthesis and not melanin itself or N-acetyldopamine (NADA), the key precursor of sclerotizing agent, were necessary for the immune responses by hemocytes and integument.

Objective: To determine the prevalence of popliteal cyst (Baker's cyst) in rheumatoid arthritis (RA), through the use of a very sensitive and non-invasive method, high resolution ultrasonography. The present is the first such report in the literature., Methods: Ninety-nine unselected consecutive patients with RA, after undergoing routine clinical and laboratory evaluation, had knee radiographs and ultrasound examinations of both knees, the popliteal fossae and calves, using an Ultramark 9ATL apparatus with a 3 MHz curved array and 10 MHz linear array heads and color doppler ability., Results: A Baker's cyst was detected in 47 patients (47.5%) and in a total of 67 out of the 198 knees (33.8%). Four of the 67 cysts were ruptured. Only 29 of the 67 cysts (43.3%) had been diagnosed clinically. A statistically significant correlation was found between the presence of a Baker's cyst and clinical and radiologic involvement of the knee by rheumatoid arthritis (p < 0.025, and p < 0.05 respectively). There was a highly significant correlation between the presence of a cyst and ultrasonographically demonstrated joint effusion (p < 0.001)., Conclusion: Baker's cyst is very common in RA but it may escape clinical detection. High resolution ultrasound scanning of the area is a simple, highly sensitive and non-invasive technique able to overcome this problem. Therefore, it should be more widely employed by clinicians in the diagnosis of popliteal cysts, which may sometimes be accompanied by significant morbidity.

Insect hemocytes (blood cells) synthesize the major nonself recognition protein (47 kDa) during 3rd instar larvae (V.J. Marmaras, S. Tsakas, Dev. Biol. 129, 294-303 (1988)). In this study we show the presence of the 47 kDa protein in plasmatocytes (main hemocyte type) and prohemocytes. In plasmatocytes this protein appears to be localized both in vesicles and in the cell surface. The cell surface-associated 47 kDa protein was released from membrane fraction by 1 M NaCl, indicating that it is not tightly bound. Bacterial lipopolysaccharide (LPS) can function on isolated hemocytes from Ceratitis capitata larvae, inducing their spreading and degranulation. During degranulation (exocytosis) the plasmatocytes release the 47 kDa protein, among others. This protein could not be normally traced in serum, nor is it released by basal secretion. The secretion of the 47 kDa protein was found to be LPS-dependent, whereas its presence on plasmatocyte surface is LPS independent. LPS-stimulated exocytosis of the 47 kDa protein appears to be dependent on protein tyrosine phosphorylation. We have now demonstrated that LPS increases tyrosine phosphorylation of 19 and 22 kDa polypeptides in C. capitata hemocytes. Inhibition of the LPS-induced tyrosine phosphorylation mediated by tyrosine kinase inhibitor, genistein, was accompanied by the inhibition of the secretion of the 47 kDa protein. These results support the hypothesis that tyrosine protein phosphorylation is a signal reaction in hemocytes after LPS exposure. These LPS responses of insect plasmatocytes show strong similarities to mammalian macrophages (S. Weinstein et al., J. Immunol. 151, 3829-3838 (1993)). In a model we propose that the LPS-independent cell surface-associated 47 kDa protein is responsible for the phagocytosis and for the formation of nodules and capsules, whereas the LPS-dependent secreting counterpart is responsible for the extracellular killing of bacteria.

The HLA A and B types of 20 Greek patients with thromboangiitis obliterans (TAO) were studied and compared with a panel of 400 controls. A nonstatistically significant increase in the frequencies of HLA B5, B7 and A9 antigens was found. These antigens were found to be associated with a relative risk of 3.47, 3.24 and 2.07 respectively. These findings are partially in agreement with those of a joint English-Swiss study which also found a negative association with B12 antigens; in the Greek population, also of European origin, a negative association was observed with the B8 antigen.