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31.
32.

Introduction

The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.

Methods

Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.

Results

Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).

Conclusions

Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed.  相似文献   
33.
ABSTRACT: BACKGROUND: HTLV-1 is associated with increased susceptibility to Mycobacterium tuberculosis infection and severity of tuberculosis. Although previous studies have shown that HTLV-1 infected individuals have a low frequency of positive tuberculin skin test (TST) and decreasing in lymphoproliferative responses compared to HTLV-1 uninfected persons, these studies were not performed in individuals with history of tuberculosis or evidence of M. tuberculosis infection. Therefore the reasons why HTLV-1 infection increases susceptibility to infection and severity of tuberculosis are not understood.The aim of this study was to evaluate how HTLV-1 may influence the clinical, bacteriologic and immunologic presentation of tuberculosis. METHODS: The study prospectively enrolled and followed 13 new cases of tuberculosis associated with HTLV-1 (cases) and 25 patients with tuberculosis without HTLV-1 infection (controls). Clinical findings, bacterial load in the sputum, x-rays, immunological response and death were compared in the two groups. RESULTS: There were no differences in the demographic, clinical and TST response between the two study groups. IFN-gamma and TNF-alpha production was higher in unstimulated cultures of mononuclear cells of case than in control patients (p < 0.01). While there was no difference in IFN-gamma production in PPD stimulated cultures, TNF-alpha levels were lower in cases than in controls (p = 0.01). There was no difference in the bacterial load among the groups but sputum smear microscopy results became negative faster in cases than in controls. Death only occurred in two co-infected patients. CONCLUSION: While the increased susceptibility for tuberculosis infection in HTLV-1 infected subjects may be related to impairment in TNF-alpha production, the severity of tuberculosis in co-infected patients may be due to the enhancement of the Th1 inflammatory response, rather than in their decreased ability to control bacterial growth.  相似文献   
34.
The increase of obesity, bad eating habits and the lack of physical exercises are highly related to dyslipidemias. Rosuvastatin is a lipid‐lowering drug and has been indicated to prevent cardiovascular diseases and to treat dyslipidemias due to its higher efficiency to reduce serum cholesterol concentrations. This study aimed to evaluate the reproductive adverse effects on sexual maturity due to rosuvastatin exposure in juvenile male rats during prepuberty. Three groups were randomly formed with newly weaned rats: control, whose rats received saline solution 0.9% and rosuvastatin at doses of 3 or 10 mg kg–1 day–1, administered orally by gavage, from postnatal day 21 until preputial separation (average of 45 days for controls and 49 days for statin‐treated animals), indicative of puberty onset. Male rats were maintained until sexual maturity and were killed on postnatal day 110. In the rosuvastatin‐treated groups, the results showed diminished follicle‐stimulating hormone, luteinizing hormone and testosterone concentrations, increased estradiol and prolactin concentrations, histopathologic alterations on testis and epididymis and decreased sperm quality. Moreover, statin‐exposed groups showed decreased expression of androgen receptor on testis and epididymis and lower expression of aquaporin‐9 on epididymal epithelium. In conclusion, administration of rosuvastatin to prepubertal male rats provoked long‐term hormonal deregulation and impaired reproduction at adulthood.  相似文献   
35.
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients.  相似文献   
36.
37.
The activation of factor XI initiates the intrinsic coagulation pathway. Until recently it was believed that the main activator of factor XI is factor XIIa in conjunction with the cofactor high molecular weight kininogen on a negatively charged surface. Two recent reports have presented evidence that in a purified system factor XI is activatable by thrombin together with the soluble polyanion dextran sulfate. To assess the physiological relevance of these findings we studied the activation of factor XI in normal and factor XII-deficient plasma. We used either kaolin/cephalin or dextran sulfate as a surface for the intrinsic coagulation pathway, tissue factor to generate thrombin via the extrinsic pathway, or the addition of alpha-thrombin directly. 125I-factor XI, added to factor XI-deficient plasma at physiologic concentrations (35 nmol/L), is rapidly cleaved on incubation with kaolin. The kinetics appear to be exponential with half the maximum cleavage at 5 minutes. Similar kinetics of factor XI cleavage are seen when 40 nmol/L factor XIIa (equal to 10% of factor XII activation) is added to factor XII-deficient plasma if an activating surface is provided. Tissue factor (1:500) added to plasma did not induce cleavage of factor XI during a 90-minute incubation, although fibrin formation within 30 seconds indicated that thrombin was generated via the extrinsic pathway. Adding 1 mumol/L alpha-thrombin (equivalent to 50% prothrombin activation) directly to factor XII deficient or normal plasma (with or without kaolin/cephalin/Ca2+ or dextran sulfate) led to instantaneous fibrinogen cleavage, but again no cleavage of factor XI was observable. We conclude that in plasma surroundings factor XI is not activated by thrombin, and that proposals of thrombin initiation of the intrinsic coagulation cascade are not supportable.  相似文献   
38.
Lu  L; Broxmeyer  HE; Moore  MA; Sheridan  AP; Gentile  P 《Blood》1985,65(1):91-99
The regulation of myelopoiesis was evaluated in B6D2F1 mice inoculated with Friend virus complex (spleen focus-forming virus plus helper virus) or helper virus alone by analyzing acidic isoferritin (AIF) and lactoferrin (LF) interactions with target cells. Under normal conditions, AIF suppresses colony and cluster formation by an Ia- antigen-positive cycling subpopulation of mouse granulocyte-macrophage progenitor cells (CFU-GM). Under the same conditions, the release of AIF-inhibitory activity and granulocyte-macrophage colony stimulatory factors (GM-CSF) from an Ia-antigen-positive subpopulation of monocytes and macrophages is suppressed by LF. Within one to two days after inoculation in vivo with Friend virus complex or helper virus, mouse CFU-GM become insensitive in vitro to suppression by purified human AIF as well as crude mouse AIF, and by four days, bone marrow, spleen, and thymus cells of these mice release much greater quantities of AIF- inhibitory activity than the cells from mice injected with control medium. The Friend virus complex itself has no influence in vitro on CFU-GM from normal mice. In addition, the release of AIF-inhibitory activity from bone marrow, spleen, and resident peritoneal cells and the release of GM-CSF from resident peritoneal cells of mice infected with Friend virus complex are not suppressed by LF. The inability of AIF to suppress colony formation by bone marrow and spleen CFU-GM from mice infected with Friend virus complex is associated with the loss of Ia (I-A subregion) antigens from CFU-GM, even though CFU-GM are in cycle. The nonresponsiveness of bone marrow, spleen, and peritoneal cells from these mice to LF suppression of AIF release and the inability of LF to influence GM-CSF release from peritoneal cells is associated with loss of Ia antigens from these cells. The above abnormalities are similar to the defects noted using cells from patients with leukemia. These results suggest that mice infected with Friend virus complex can serve as a model for investigating abnormalities in cell regulation and their relationships to disease progression.  相似文献   
39.
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status.  相似文献   
40.
Summary In order to investigate the role played by zidovudine (ZDV) as immune modulator, particularly on B-cell response, the anti-V3 loop spectrotype in 115 sera from 26 HIV-infected individuals was evaluated, prior to and during treatment with ZDV, by isoelectric focusing and reverse blotting (IEF-RB), a technique useful for indirectly measuring the activity and the number of B-cell clones. All 18 patients showing seroreactivity by IEFRB displayed a clear oligoclonal banding pattern, with no change in the spectrotype (i.e. new bands), in sequential analysis over the course of therapy. Only minor changes in band intensity were found, without any correlation with ZDV treatment or CD4+ cell count. In addition, among the sera reactive in spectrotypic analysis, the percentage of those with p24 antigen positivity was significantly lower than those with no detectable p24 antigen (19.8% vs 80.2%, respectively, p=<0.0001, Fisher's exact test). In conclusion, it could not be demonstrated by IEFRB that there was any effect of ZDV on the activity and the number of anti-V3 specific B-cell clones. This data is in line with previous studies showing the constancy of anti-gp120 antibody spectrotype over the long course of the disease.
Anti-V3-Loop Spektrotyp bei HIV-Infizierten während Zidovudin-Behandlung
Zusammenfassung Der Anti-V3-Loop-Spektrotyp wurden in 115 Seren von 26 HIV-Infizierten vor und nach Zidovudin-Therapie bestimmt, um die Rolle von Zidovudin als Immunmodulator, vor allem der B-Zell-Antwort, zu prüfen. Als Methoden wurden isoelektrische Fokussierung und reverses Blotting (IEFRB) eingesetzt, die sich für die indirekte Bestimmung der Aktivität und der Zahl der B-Zell-Klone als brauchbar erwiesen haben. Bei allen 18 seroreaktiven Patienten stellten sich eindeutige oligoklonale Bandenmuster dar. In Verlaufsanalysen während der Therapie war keine Änderung im Spektrotyp, d. h. keine neuen Banden, zu erkennen. Die Bandenintensität änderte sich nur wenig, wobei keine Beziehung zur Zidovudin-Therapie oder den CD4+ Zellzahlen bestand. In den Spektrotyp-positiven Seren war nur bei einem kleinen Anteil auch p24-Antigen nachzuweisen (19,8% positive gegen 80,2% p-24-Antigen negative Seren; p0,0001, Fisher's exakter Test). Zusammenfassend fand sich mit IEFRB kein Einfluß von Zidovudin auf die Aktivität und die Zahl anti-V3-spezifischer B-Zell-Klone. Dies stimmt mit den Ergebnissen früherer Studien überein, in denen Konstanz des anti-gp120-Antikörper-Spektrotyps im Langzeitverlauf der Erkrankung festgestellt wurde.
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