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81.
OBJECTIVE: To investigate the effect of pulse cyclophosphamide treatment on hepatitis C virus (HCV) kinetics and quasispecies in interferon alpha (IFNalpha) resistant HCV related cryoglobulinaemic vasculitis. METHODS: Reports on two patients with severe manifestations of HCV related cryoglobulinaemia who failed to respond to interferon alpha are given. Both patients were treated with pulse cyclophosphamide (750-1000 mg/month for six and 11 months, respectively). HCV RNA was quantified and HCV quasispecies determined in cryoprecipitates and supernatants before and during treatment. RESULTS: Cryocrit and complement activation decreased in both patients with rebound of cryocrit in one case during continuing pulse cyclophosphamide treatment. Vasculitic symptoms improved. Alanine aminotransferase (ALT) levels and HCV viral load (0.2-0.4 log) increased slightly and reached pretreatment levels after cyclophosphamide was stopped. A highly heterogeneous quasispecies was found in the cryoprecipitate and supernatant of one patient, whereas the viral population was homogeneous in the other patient. After six cycles of cyclophosphamide, viral distances decreased non-significantly. However, phylogenetic analysis showed the evolution of distinct viral strains in one patient and replacement of the main viral population by another population in the second patient. CONCLUSIONS: Immunosuppressive treatment with pulse cyclophosphamide has a temporary limited effect on HCV associated cryoglobulinaemia and leads to a reversible increase of ALT levels and HCV viral load. Short term immunosuppression does not affect the viral heterogeneity as measured by amino acid and nucleotide distances in the hypervariable region 1 of HCV. A change of quasispecies was observed, but further studies are needed to evaluate if this does affect the outcome of IFNalpha treatment in such patients.  相似文献   
82.
Linker  CA; Ries  CA; Damon  LE; Rugo  HS; Wolf  JL 《Blood》1993,81(2):311-318
We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.  相似文献   
83.
Dighiero  G; Bodega  E; Mayzner  R; Binet  JL 《Blood》1980,55(1):93-100
A new quantitative immunoperoxidase method is presented for determining absolute amounts of peroxidase and, consequently, surface antigen densities of individual cells in B lymphocytes from normal individuals, from subjects with CLL and prolymphocytic leukemia, and during ontogeny of B lympocytes in the mouse. The following results were observed: (1) The density of B antigenic sites were lower on CLL than on normal B lymphocytes. (2) The B antigens density of leukemic lymphocytes varied less from cell to cell, forming a homogeneous peak on histograms. (3) In a very rare case of CLL, the antigen density was measured at the time of initial diagnosis (22,500 sites or 647 U) and during the development of a blastic crisis (135,000 sites or 2576 U). The cell by cell distribution changed from a homogeneous peak with a low number of antigenic sites per cell to a heterogeneous peak with a high number of antigenic sites per cell. (4) In prolymphocytic leukemia, the density of B antigenic sites was greater than on normal B lymphocytes and much more heterogeneous than on CLL lymphocytes. (5) During ontogeny of B lymphocytes in the mouse, maturation is associated with the appearance of a population of cells of intermediate to high Smig density. The finding of a decrease in, and altered distribution of, surface markers in CLL is compared with these ontologic findings in the mouse, and the concept that a monoclonal B lymphocyte in CLL may be arrested at a particular stage in its differentiation is discussed.  相似文献   
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86.

Background

Lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH) mainly depend on alpha1-adrenoreceptors (α1-ADR) stimulation, but a link with oxidative stress (OS) is also involved. D-004, a lipid extract of Roystonea regia fruits, antagonizes ADR-induced responses and produces antioxidant effects. The objective of this study was to investigate whether D-004 produce antioxidant effects in rats with phenylephrine (PHE)-induced urodynamic changes.

Methods

Rats were randomized into eight groups (ten rats/group): a negative vehicle control and seven groups injected with PHE: a positive control, three treated with D-004 (200, 400 and 800 mg/kg) and three others with tamsulosin (0.4 mg/kg), grape seed extract (GSE) (250 mg/kg) and vitamin E (VE) (250 mg/kg), respectively.

Results

Effects on urinary total volume (UTV), volume voided per micturition (VM), malondialdehyde (MDA) and carbonyl groups (CG) concentrations in prostate and bladder homogenates were study outcomes. While VM and UTV lowered significantly in the positive control as compared to the negative control group, the opposite occurred with prostate and bladder MDA and CG values. D-004 (200-800 mg/kg) increased significantly both VM and UTV, lowered significantly MDA in prostate and bladder homogenates, and reduced GC levels only in the prostate. Tamsulosin increased significantly VM and UTV, but unchanged oxidative variables. GSE and VE unchanged the UTV, whereas VE, not GSE, modestly but significantly attenuated the PHE-induced decrease of VM.

Conclusions

Single oral administration of D-004 (200-800 mg/kg) was the only treatment that ameliorated the urodynamic changes and reduced increased oxidative variables in the prostate of rats with PHE-induced prostate hyperplasia.  相似文献   
87.
88.

Objectives

In order to analyze the molecular epidemiology of human astroviruses (HAstV) in Germany, a retrospective long-term study was performed to characterize circulating human astrovirus in patients with acute gastroenteritis in Germany.

Methods

A total of 2877 stool samples, collected between January 2010 and December 2015 from sporadic cases and outbreaks of acute gastroenteritis were retrospectively analyzed for astrovirus. A two-step PCR algorithm was developed and used to identify and characterize human astrovirus infections.

Results

Overall, 143 samples were astrovirus-positive (5.0%). Astrovirus infection was most frequently detectable in samples from children of 3–4 years (15%) followed by children of 1–2 years (8.6%), detection rates in adults were lower (1%–3.6%). A high number (71.3%) of co-infections, mainly with noro- or rotaviruses, were identified. Genotyping revealed that at least ten genotypes from all four human MAstV species were circulating in the study population. HAstV-1 was predominant in different age groups. Novel HAstV (MLB and VA genotypes) were also circulating in Germany.

Conclusion

Our findings give new insights into the circulation and genetic diversity of human astroviruses in patients with acute gastroenteritis. The novel HAstV-MLB and -VA genotypes could be characterized firstly in Germany while the analysis showed that these viruses have been dispersed in Germany since 2011 as a causative agent of acute gastroenteritis.  相似文献   
89.
IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent of coronavirus disease (COVID-19). People infected with SARS-CoV-2 may exhibit no or mild non-specific symptoms; thus, they may contribute to silent circulation of the virus among humans. Since SARS-CoV-2 RNA can be detected in stool samples, monitoring SARS-CoV-2 RNA in waste water (WW) has been proposed as a complementary tool to investigate virus circulation in human populations.AimTo test if the quantification of SARS-CoV-2 genomes in WW correlates with the number of symptomatic or non-symptomatic carriers.MethodWe performed a time-course quantitative analysis of SARS-CoV-2 by RT-qPCR in raw WW samples collected from several major WW treatment plants in Greater Paris. The study period was 5 March to 23 April 2020, including the lockdown period in France (from 17 March).ResultsWe showed that the increase of genome units in raw WW accurately followed the increase of human COVID-19 cases observed at the regional level. Of note, the viral genome could be detected before the epidemic grew massively (around 8 March). Equally importantly, a marked decrease in the quantities of genome units was observed concomitantly with the reduction in the number of new COVID-19 cases, 29 days following the lockdown.ConclusionThis work suggests that a quantitative monitoring of SARS-CoV-2 genomes in WW could generate important additional information for improved monitoring of SARS-CoV-2 circulation at local or regional levels and emphasises the role of WW-based epidemiology.  相似文献   
90.
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