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71.
Cardiac abnormalities such as mitral valve prolapse (MVP) are reported to
be common features of the Ehlers Danlos syndrome (EDS), and it has been
suggested that the majority of patients with type IV EDS will have cardiac
involvement and vascular aneurysms. However, the evidence for valve lesions
is inconsistent and often based on early clinical studies using mainly
M-mode echo. We studied 33 patients (six male, 27 female; median age 35 yr)
with EDS (30 type I, II or III, three type IV) and 30 age- and sex-matched
controls. The study assessed skin stretch and joint hypermobility using
Beighton and Contompasis scores. Echocardiographic examination included
standard two-dimensional views from the parasternal and apical windows, and
measurement of the aorta at four sites (annulus, sinotubular junction, arch
and abdominal aorta). Echocardiographic abnormalities were found in four
patients (12.1%) (one atrial septal aneurysm, one tricuspid prolapse, two
MVP) and two controls (6.7%). MVP was found in 6.1% of EDS patients and 7%
of controls. Seven patients had previously been diagnosed as having MVP;
only two were shown to have true MVP using current criteria. None of those
with type IV EDS had any echocardiographic abnormality. No patients with
EDS had mean aortic dimensions outside the normal range at any of the
points tested. Cardiac symptoms were more frequent amongst the patients
than controls (atypical chest pain 48%, P = 0.0001; palpitation 39%, P =
0.001; exertional dyspnoea 30%). A wide range of rheumatological complaints
were reported (current arthralgia 75%; recent back pain 72%, P = 0.005;
recurrent dislocation 72%). Contrary to earlier published observations, we
have not found an increased incidence of cardiac abnormalities in EDS. This
syndrome may be relatively more benign, from the cardiac point of view,
than was previously thought.
相似文献
72.
Priming of human neutrophils with N-formyl-methionyl-leucyl- phenylalanine by a calcium-independent, pertussis toxin-insensitive pathway 总被引:1,自引:0,他引:1
Resting neutrophils may be "primed" to augmented effector function, eg, superoxide (O2-) production in the respiratory burst, upon a second stimulation with a variety of soluble agonists including formylated methionyl-leucyl-phenylalanine (FMLP) and phorbol myristate acetate (PMA). At priming concentrations of FMLP (5 x 10(-9) mol/L) that did not initiate O2- generation, two metabolic activities were noted: (1) approximately a threefold increase in the baseline intracellular calcium (Ca++i) level, that was not dependent on extracellular Ca++, and (2) a rapid rise in intracellular pH that was blocked by 5-(N,N- dimethyl) amiloride (DA), that had no effect on the Ca++i response to priming. Furthermore, there were no significant increases in inositol metabolites in cells primed and stimulated with FMLP compared with cells receiving the stimulating dose of FMLP alone and pretreatment with pertussis toxin (PT) (before the addition of the priming -5 x 10(- 9) mol/L dose of FMLP), whereas abolishing the response to FMLP during the second stage of stimulation, had (1) no effect on FMLP-primed cells subsequently stimulated with PMA, and (2) only partially ablated the rise in Ca++i initiated with FMLP. That FMLP priming involved distinctive processes to those of the well characterized FMLP-coupled Ca++-dependent activation cascade was shown by the full priming effect attained in a Ca++-free buffer, which did not sustain an O2- response to a second-stage FMLP stimulation, but sustained a primed response to PMA. These data demonstrate that FMLP primes human neutrophils by a Ca++-independent and PT-insensitive pathway, offering a functional model for studying heterogeneous FMLP receptor-coupled reactions. 相似文献
73.
74.
Thirty-two patients treated on consecutive Southwest Oncology Group (SWOG) protocols for malignant lymphoma were subsequently diagnosed as having lymphoblastic lymphoma. Combination chemistry, usually adriamycin-based, produced complete responses (CR) in 17 patients (53%). Median survival was 15 mo. Patients achieving a CR survival significantly longer than patients with partial or no response (p < 0.01). Ten of 24 patients not receiving central nervous system (CNS) prophylaxis developed leptomeningeal lymphoma while none of the seven patients who received prophylactic intrathecal cytosine arabinoside or methotrexate developed CNS lymphoma (p = 0.04). Implications of these results for planning future treatment programs of lymphoblastic lymphoma are discussed. 相似文献
75.
Platelet adherence at high wall shear rates requires plasma von Willebrand factor (vWF). Clinically, the ristocetin cofactor (RCof) activity is the only widely available assay for vWF function. When purified vWF is treated with neuraminidase to yield asialo-vWF (AS- vWF), its RCof activity is increased by 20% to 40%. AS-vWF binds to normal human platelets independently of ristocetin and induces platelet aggregation in the presence of fibrinogen. To determine whether AS-vWF also shows an enhanced capacity to support platelet adherence to subendothelium, we used the Baumgartner technique. Intact vWF, AS-vWF, or AS-vWF treated with beta-galactosidase (asialo, agalacto-vWF; AS,AG- vWF) was added to normal citrated whole blood before perfusion over human umbilical artery segments (wall shear rate, 2,600 sec-1). Four micrograms per milliliter AS-vWF caused a 69% reduction in total platelet adherence compared with citrated whole blood (P less than .001), and 4 micrograms/mL AS,AG-vWF led to a 48% reduction (P less than .005). With 4 micrograms/mL intact vWF, the platelet adherence values were not significantly different from the controls. No significant differences in subendothelial platelet thrombi or postperfusion platelet counts were evident among any of the groups. In reconstituted afibrinogenemic perfusates, 4 micrograms/mL AS-vWF caused a 42% reduction in platelet adherence (P less than .05). Thus, AS-vWF is a potent inhibitor of platelet adherence, despite its enhanced RCof specific activity. Abnormalities in vWF carbohydrate may play a role in impaired primary hemostasis in some patients with von Willebrand's disease. 相似文献
76.
Nitric oxide (NO) is a paramagnetic gas that has been implicated in a wide range of biologic functions. The common pathway to evoke the functional response frequently involves the formation of an iron- nitrosyl complex in a target (heme) protein. In this study, we report on the interactions between NO and cobalt-containing vitamin B12 derivatives. Absorption spectroscopy showed that of the four Co(III) derivatives (cyanocobalamin [CN-Cbl], aquocobalamin [H2O-Cbl], adenosylcobalamin [Ado-Cbl], and methylcobalamin [MeCbl]), only the H2O- Cbl combined with NO. In addition, electron paramagnetic resonance spectroscopy of H2O-Cbl preparations showed the presence of a small amount of Cob-(II)alamin that was capable of combining with NO. The Co(III)-NO complex was very stable, but could transfer its NO moiety to hemoglobin (Hb). The transfer was accompanied by a reduction of the Co(III) to Co(II), indicating that NO+ (nitrosonium) was the leaving group. In accordance with this, the NO did not combine with the Hb Fe(II)-heme, but most likely with the Hb cysteine-thiolate. Similarly, the Co(III)-NO complex was capable of transferring its NO to glutathione. Ado-Cbl and Me-Cbl were susceptible to photolysis, but CN- Cbl and H2O-Cbl were not. The homolytic cleavage of the Co(III)-Ado or Co(III)-Me bond resulted in the reduction of the metal. When photolysis was performed in the presence of NO, formation of NO-Co(II) was observed. Co(II)-nitrosyl oxidized slowly to form Co(III)-nitrosyl. The capability of aquocobalamin to combine with NO had functional consequences. We found that nitrosylcobalamin had diminished ability to serve as a cofactor for the enzyme methionine synthase, and that aquocobalamin could quench NO-mediated inhibition of cell proliferation. Our in vitro studies therefore suggest that interactions between NO and cobalamins may have important consequences in vivo. 相似文献
77.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
78.
79.
80.
U PODDAR Y CHAWLA RK DHIMAN K VAIPHEI RK VASISHTA JB DILAWARI 《Journal of gastroenterology and hepatology》1998,13(1):109-111
Ascites may be associated with fulminant hepatic failure (FHF), but spontaneous bacterial peritonitis (SBP) is an extremely rare complication. We report on two patients with FHF who developed SBP. One patient died and the other recovered. 相似文献