恩替卡韦与阿德福韦对HBeAg(+)初治者12周降低HBV DNA病毒动力学的比较研究

目的比较ETV和ADV治疗核苷初治慢性乙型肝炎患者早期抗病毒疗效;通过12周治疗,探索治疗(ETV或ADV)起始时期HBV动力学应答情况;比较12周时达到HBV DNA临床显著性降低(<104copies/ml)的患者比例;与ADV比较,评价ETV的安全性。方法随机、开放、比较ETV 0.5mg/d,ADV 10mg/d的疗效。在给药的第1～14天、第3、4、6、8、10、12周时对血清HBV DNA进行检测。2个双相模型分别采用了2种治疗:①3-参数样条模型测评斜率;②4-参数指数式衰减模型测评疗效和游离病毒的半衰期。显著性评价依据双侧t检验。结果HBV DNA平均基线为10.45log10copies/ml(ETV)和9.89log10copies/ml(ADV),12周时HBV DNA平均改变值(log10copies/ml),ETV组患者(n=33)为:-6.23,而ADV组患者(n=32)仅为-4.42(P<0.0001)。所有ETV治疗的患者HBV DNA平均至少降低3.88log10copies/ml,ADV治疗的患者仅为0.95log10copies/ml。此外,与ETV相比,ADV治疗组不同患者之间病毒载量下降的差异性较大。治疗导致2组病毒载量出现双相下降,第一相下降迅速,持续10d。由此得出,循环的病毒半衰期为14h(ETV)和26h(ADV)。2个治疗组病毒下降的差异在第10天就体现出来,ETV治疗组病毒下降更低,2组间有显著差异。12周时,52%(17/33)ETV治疗患者HBV DNA低于10000 copies/ml,而ADV组为25%(8/32)。整个研究过程中,2种抗病毒药物耐受性均好,安全性相似。结论治疗HBeAg( )核苷初治患者,与ADV比较,ETV能迅速、强效降低HBV DNA,显示出更好的抗病毒活性。     

Outcome of planned pregnancies in systemic lupus erythematosus: a prospective study on 62 pregnancies

We conducted a prospective study in order to determine planned pregnancy outcome in systemic lupus erythematosus followed in a tertiary referral centre. Pregnancy was authorized if disease was inactive on 20 mg/day prednisone or less for at least 1 yr. Upon the diagnosis of pregnancy, systematic corticosteroids consisting of 10 mg/day prednisone or more were started. In the case of antiphospholipid antibodies, 100 mg/day aspirin was added, replaced by heparin in the pre-partum period. In the case of antiphospholipid syndrome complicated by previous thrombotic events or fetal losses despite aspirin, heparin was prescribed. One woman with a history of atrioventricular block was treated with dexamethasone. Patients were monitored by medical and obstetrical examination, and laboratory tests carried out at least monthly and a quarterly echography. Among 62 pregnancies in 38 women, lupus flare was observed in 27% of the cases, 6% of which occurred in the post-partum period. Flares were moderate except in one renal involvement in a woman with prior diffuse proliferative glomerulonephritis. Therapy was not modified in half of the cases. Pregnancy ended in early spontaneous abortion not related to lupus flare (n = 10), stillbirth (n = 2). induced abortion (n = 2), preterm birth (n = 29) and full-term birth (n = 19). Caesarean section was performed in nine cases. A severe infection occurred in two premature neonates. Another premature neonate was growth retarded. Two children had cutaneous neonatal lupus. No child died, neither had atrioventricular block. Stillbirth and severe prematurity were more common in mothers with antiphospholipid syndrome. After exclusion of early spontaneous and induced abortions, the live birth rate was 96%, that is close to the French general population. The main problem remains a high rate of prematurity, but without maternal or neonatal death.      

Analysis of factors associated with low peripheral blood progenitor cell collection in normal donors

BACKGROUND: Predictive factors of the response to rHuG-CSF in normal donors have not been extensively studied. STUDY DESIGN AND METHODS: We analyzed factors influencing CD34+ cell yield in the 1st day of collection in 261 healthy donors from the Spanish National Donor Registry. The median age was 38 years (range, 2-72). The median dose of rHuG-CSF was 10 microg per kg per day (range, 5-20) over 4 days. In 103 donors (40%), <4 x 10(6) per kg CD34+ cells were collected. The variables that were analyzed included age, sex, weight, basal complete blood cell count, dose, type of rHuGCSF and schedule of administration, and maximum WBC count before apheresis. RESULTS: By univariate analysis, the maximum WBC count (<50 vs. >or=50 x 10(9)/L, p = 0.004), advanced age (p = 0.008), and number of daily rHuG-CSF doses (one vs. two; p = 0.01) correlated with the number of CD34+ cells collected. By multivariate analysis, donors age (<38 vs. >or=38 years; p = 0.014) and a single daily dose of rHuG-CSF (p = 0.005) were the two variables that significantly predicted a low CD34+ cell yield. CONCLUSION: Donors' age, with a threshold of 38 years or more, and the rHuG-CSF schedule are the factors that significantly affected CD34+ cell mobilization and collection in healthy donors.     

Local up-regulation of neuropeptide receptors in host blood vessels around human colorectal cancers

BACKGROUND & AIMS: Neuropeptide receptors, expressed at high density by neoplastic cells, can be instrumental for diagnosis and therapy. However, little is known about neuropeptides and neuropeptide receptors in the tumor bed. The aim of this study was to study the expression of two neuropeptide receptors in peritumoral blood vessels. METHODS: Somatostatin and substance P receptors were measured using in vitro receptor autoradiography in well-defined submucosal and subserosal vessels located in the immediate surroundings of human colorectal carcinomas or in normal colon taken at increasing distances from the tumor. RESULTS: Both receptors were 3-5-fold overexpressed in the host veins within a 2-cm-wide area surrounding human primary colorectal carcinomas compared with veins located at 5-10-cm distance in normal gut tissue. The expression of peritumoral vascular somatostatin receptor and substance P receptor appears independent of receptor expression in the tumor, of tumor stage, and of the grade of local inflammation. CONCLUSIONS: These biochemical alterations of veins in the immediate vicinity of tumors represent a novel tumor-related site of expression for the two receptors and may point to a new biological principle of host-tumor interaction. Thus, vascular regulatory mechanisms in the tumor bed may be important for tumor development and metastasis and may be used as a target for tumor therapy. (Gastroenterology 1996 Jun;110(6):1719-26)     

Neutrophil deactivation by influenza A viruses: mechanisms of protection after viral opsonization with collectins and hemagglutination-inhibiting antibodies

Bacterial superinfections are a major cause of morbidity and mortality during influenza A virus (IAV) epidemics. Depression of phagocyte functions resulting from attachment of the IAV hemagglutinin (HA) to cell surface sialo-glycoproteins is a likely contributory cause of these infections. We have proposed that the group of collagenous lectins (termed collectins) present in blood and pulmonary surfactant play a role in initial host defense against IAV. We used here several recombinant human surfactant protein D (RhSP-D) preparations to determine the mechanism through which opsonization of IAV with collectins protects neutrophils against the deactivating effects of IAV on cellular respiratory burst responses in vitro. RhSP-D was markedly more potent than antibodies that inhibited viral hemagglutination activity (anti-HA antibodies) at protecting neutrophils in this assay. Unlike the anti-HA antibodies, RhSP-D was protective at concentrations that minimally inhibited viral hemagglutination activity. Two related features of SP-D--the degree of multimerization and the ability to cause aggregation of IAV particles--were critical determinants of the ability of SP-D to protect neutrophils against deactivation. Similarly SP-D-induced viral aggregate formation resulted in enhanced IAV binding to neutrophils and potentiated the ability of the virus itself to trigger neutrophil respiratory burst responses. In contrast to the case of IAV-antibody complexes, SP-D-IAV complexes attached to and activated neutrophils through a neuraminidase-sensitive mechanism (ie, similar to unopsonized IAV). These results indicate that collectin-mediated viral aggregation per se may be an important host defense mechanism not only by virtue of reducing the number of infectious viral particles, but also by promoting phagocyte responsiveness.     

Persistent clonal excess and skewed T-cell repertoire in T cells from patients with hairy cell leukemia

Hairy cell leukemia (HCL) is characterized by a severe T-cell-mediated immune deficiency. At the same time, spontaneous T-cell activation is noted when splenic T cells are studied in vivo and in vitro. Therefore, we searched for oligoclonal T-cell populations in the blood and spleens of 25 patients with HCL using a T-cell receptor gamma-polymerase chain reaction (TCR gamma-PCR). Subsequently, in 6 patients, the CDR3 length and conformation from 22 different TCRBV subfamilies were analyzed after PCR amplification of cDNA using TCRBV subfamily-specific primers. T cells from 15 of 25 HCL patients showed clonal excess by the TCR gamma-PCR. In fluorescence-activated cell sorted T-cell subsets, more clonal bands were observed than in the unseparated T cells, with most of these in CD8+ subsets, but also in CD4+, CD3+ gamma/delta+, and a double-negative CD3+ alpha/beta+ subset. In other B-cell malignancies, 6 of 16 samples showed oligoclonal T cells, whereas only 2 of 18 normal spleen and blood samples showed abnormal bands. Analysis of the TCRBV subfamilies disclosed in all 6 HCL patients a markedly abnormal pattern, with many clonal bands in 5 to 15 subfamilies, and absent or abnormal weak patterns in another 1 to 8 subfamilies. In comparison, 6 normal samples (2 spleens and 4 blood samples) showed in only 1 blood donor 1 clonal band. Two patients with active HCL but without infections or treatment were tested several times during the course of the disease and showed a complete identical skewed T-cell repertoire with the same oligoclonal T-cell populations. In conclusion, T cells in the blood and spleen of HCL patients show impressive abnormalities with many oligoclonal T-cell populations and a very restricted and skewed TCRBV repertoire.     

Granulocyte-macrophage colony-stimulating factor receptor: stage- specific expression and function on late B cells

Granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors (GMR) are expressed on myeloid cells throughout their maturational sequence. During myelopoiesis, GM-CSF induces the proliferation of precursors and has multiple effects on more mature cells; such effects include induction of maturation and priming for subsequent stimulation. GMR is expressed on a range of other cell types including acute leukemic blasts of myeloid and lymphoid lineage, but has been little studied on more mature lymphoid cells. Using sensitive triple-layer immunophenotypic techniques, we show here that both the alpha and beta c chains of the GMR are expressed on hairy cells (HCs) and myelomatous plasma cells (PCs), but not on chronic lymphocytic leukemia (CLL) or prolymphocytic leukemia (PLL) lymphocytes. The receptor was demonstrable on normal PCs in tonsil, but not on either activated or resting tonsillar B cells or on circulating normal B lymphocytes. The expression of the receptor is therefore stage specific, rather than a feature of activation. Perhaps, surprisingly, in view of its effects on myeloid cells, GM-CSF did not stimulate the proliferation or differentiation of HCs and did not protect them from apoptosis. However, the cytokine had a profound effect on the interaction of the HC with its environment. Thus, the cytokine caused a major cytoskeletal reorganization resulting in the inhibition of motility and loss of adhesion to cellular and matrix ligands. These studies indicate the importance of GM-CSF outside myelopoiesis and demonstrate a previously unrecognized stage specific role for the cytokine in B-cell biology. Taken together with our previous report that M-CSF enhances B-cell motility, the present findings indicate that myeloid growth factors act in concert to facilitate the controlled migration of certain B cells into and within tissues.     

Interferon-gamma suppresses T-cell proliferation to mitogen via the nitric oxide pathway during experimental acute graft-versus-host disease

The development of graft-versus-host disease (GVHD) is associated with long-lasting and profound deficits in immune function that lead to increased morbidity and mortality after bone marrow transplantation (BMT). We investigated a mechanism of T-cell immunodeficiency in response to mitogen or alloantigen in an experimental model of acute GVHD by analyzing the roles of two immunosuppressive moieties: interferon gamma (IFN-gamma) and nitric oxide (NO). Splenocytes from mice with GVHD did not proliferate either to the T-cell mitogen, concanavalin A (Con A), or to host alloantigens, but only mitogen- activated cultures produced increased levels of NO. The abrogation of NO synthesis with LG-mono-methyl-arginine (NMMA) restored mitogen- induced proliferation but not the response to host antigens. The mechanism of impared proliferation to mitogen was dependent on IFN- gamma because blockade of this cytokine in culture inhibited NO production and restored proliferation to Con A to levels similar to those in transplanted control mice without GVHD. NMMA did not substantially reduce IFN-gamma levels, demonstrating that NO acted distally to IFN-gamma in the pathway of immunosuppression in response to mitogen. Furthermore, the prevention of IFN-gamma production in vivo after allogeneic BMT, by transplantation of polarized type 2 donor T cells (secreting interleukin-4 but not IFN-gamma), also prevented NO production and restored splenocyte responses to mitogen. Our data demonstrate the existence of NO-dependent and NO-independent pathways involved in suppression of T-cell proliferation during acute GVHD. Excess NO synthesis appears to be one mechanism by which IFN-gamma induces immunodeficiency after allogeneic BMT.     

p53 functional impairment and high p21waf1/cip1 expression in human T- cell lymphotropic/leukemia virus type I-transformed T cells

Human T-cell lymphotropic/leukemia virus type I (HTLV-I) is associated with T-cell transformation both in vivo and in vitro. Although some of the mechanisms responsible for transformation remain unknown, increasing evidence supports a direct role of viral as well as dysregulated cellular proteins in transformation. We investigated the potential role of the tumor suppressor gene p53 and of the p53- regulated gene, p21waf1/cip1 (wild-type p53 activated fragment 1/cycling dependent kinases [cdks] interacting protein 1), in HTLV-I- infected T cells. We have found that the majority of HTLV-I-infected T cells have the wild-type p53 gene. However, its function in HTLV-I- transformed cells appears to be impaired, as shown by the lack of appropriate p53-mediated responses to ionizing radiation (IR). Interestingly, the expression of the p53 inducible gene, p21waf1/cip1, is elevated at the messenger ribonucleic acid and protein levels in all HTLV-I-infected T-cell lines examined as well as in Taxl-1, a human T- cell line stably expressing Tax. Additionally, Tax induces upregulation of a p21waf1/cip1 promoter-driven luciferase gene in p53 null cells, and increases p21waf1/cip1 expression in Jurkat T cells. These findings suggest that the Tax protein is at least partially responsible for the p53-independent expression of p21waf1/cip1 in HTLV-I-infected cells. Dysregulation of p53 and p21waf1/cip1 proteins regulating cell-cycle progression, may represent an important step in HTLV-I-induced T-cell transformation.     

Dominant type 1 von Willebrand disease caused by mutated cysteine residues in the D3 domain of von Willebrand factor

No defects have been reported in moderately severe type 1 von Willebrand disease (vWD) with a clear autosomal dominant inheritance pattern, and the mechanism underlying this form of vWD remains obscure. We have studied a type 1 vWD family with such a dominant phenotype. The entire coding sequence of the von Willebrand factor (vWF) gene was analyzed by direct sequencing of DNA fragments amplified by polymerase chain reaction. Only one candidate mutation T(3445)-->C in exon 26 was detected that predicts a replacement of cysteine (C) at position 386 of the mature vWF subunit by arginine (R). Both mutant and normal vWF alleles were expressed as shown by analysis of platelet mRNA. This substitution segregates with vWD in the family and was not found in 100 unrelated individuals. The recombinant mutant vWF(C386R) was characterized by expression in 293T cells. The secretion of vWF(C386R) was greatly impaired due to retention in the endoplasmic reticulum. In cotransfections of normal and mutant vWF constructs, the vWF(C386R) subunits caused a dose-dependent decrease in the secretion of vWF. The multimer pattern remained nearly normal and consistent with a dominant vWD type 1 phenotype. The importance of the cysteine residues in the D3 domain of vWF in the pathogenesis of dominant type 1 vWD was further shown by the detection of another cysteine mutation, Cys367-->Phe, in two additional unrelated patients with a similar dominant type 1 vWD phenotype. We conclude that the loss of cysteine pairing in the D3 domain, leaving one free cysteine, can induce a purely quantitative deficiency of vWF by dominantly suppressing the secretion of normal vWF.