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1.
Previously, the lower generation (DAB 8-generation 2 and DAB 16-generation 3) polypropylenimine dendrimers have been shown to be effective gene delivery systems in vitro. In the current work, we sought to: (a) test the effect of the strength of the carrier, DNA electrostatic interaction on gene transfer and (b) to study the in vivo gene transfer activity of these low molecular weight (<1687 Da) non-amphiphilic plain and quaternary ammonium gene carriers. Towards this aim, methyl quaternary ammonium derivatives of DAB 4 (generation 1), DAB 8, DAB 16 and DAB 32 (generation 4) were synthesised to give Q4, Q8, Q16 and Q32, respectively. Quaternisation of DAB 8 proved to be critical in improving DNA binding, as evidenced by data from the ethidium bromide exclusion assay and dendrimer-DNA colloidal stability data. This improved colloidal stability had a major effect on vector tolerability, as Q8-DNA formulations were well tolerated on intravenous injection while a similar DAB 8-DNA dose was lethally toxic by the same route. Quaternisation also improved the in vitro cell biocompatibility of DAB 16-DNA and DAB 32-DNA dendrimer complexes by about 4-fold but not that of the lower generation DAB 4-DNA and DAB 8-DNA formulations. In contrast to previous reports with non-viral gene delivery systems, the intravenous administration of DAB 16-DNA and Q8-DNA formulations resulted in liver targeted gene expression as opposed to the lung targeted gene expression obtained with the control polymer-Exgen 500 [linear poly(ethylenimine)] and a lung avoidance hypothesis is postulated. We conclude that the polypropylenimine dendrimers are promising gene delivery systems which may be used to target the liver and avoid the lung and also that molecular modifications conferring colloidal stability on gene delivery formulations have a profound effect on their tolerability on intravenous administration.  相似文献   
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We present a patient with an asymptomatic painless medial elbow swelling of one year's duration, which was diagnosed as a ganglion originating from a non-united avulsion fracture of the medial epicondyle with a pseudarthrosis. Medial elbow ganglia are unusual lesions typically arising from the medial aspect of the ulnohumeral joint capsule, often in combination with symptoms of cubital tunnel syndrome. To our knowledge, a ganglion arising from a pseudarthrosis has not been reported in the literature, and should be considered in the differential diagnoses of lesions encountered over the site of fracture non-union in proximity to a joint.  相似文献   
4.
Chen YH  Lee MF  Lan JL  Chen CS  Wang HL  Hwang GY  Wu CH 《Allergy》2005,60(12):1518-1523
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens.  相似文献   
5.
Between 1990 and 1997, we performed 29 allogeneic BMTs for acute lymphoblastic leukemia (ALL) patients with HLA-identical sibs. Their median age was 31 years (range 15 to 43); there were 15 males and 14 females. The conditioning protocol was Cy-TBI (n = 15), VP16-Cy-TBI(n = 12), CBV (n = 1) and Bu-Cy (n = 1). Cyclosporin and methotrexate were used for GVHD prophylaxis. The median disease-free survival (DFS) was 12 months (range 1 to 92) with an actuarial 4-years DFS of 42.3 per cent. Three patients died of transplant-related complications before 100 days. Relapse occurred in 11 cases at a median time of 5 months (range 3 to 14). All nine patients relapsing within one year died form resistant leukemia. Three patients died of late treatment-related complications. There were 13 survivors (median follow-up 38 months, range 12-98), with 12 in remission. Only four had limited cGVHD, and all had 100 per cent performance scores. One patient also cleared her chronic hepatitis B carrier status due to acquired immunity. The DFS rates amongst CR1 cases and R1/CR2 cases were comparable (p = 0.39). No long-term DFS is obtained from patients with resistant disease (n = 4). The survival results for BMT at CR1 were superior to those using intensive chemotherapy consolidation (p = 0.29), mainly due to poor late results in the chemotherapy arm. For young ALL patients with HLA-matched siblings, the option of BMT should be considered in light of local consolidation survival results.  相似文献   
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OBJECTIVES:  Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence worldwide. This study aimed to validate the NAFLD fibrosis score in the Chinese population.
METHODS:  NAFLD patients were prospectively recruited for liver biopsy and blood tests. The NAFLD fibrosis score was calculated as −1.675 + 0.037 × age (yr) + 0.094 × BMI (kg/m2) + 1.13 × impaired fasting glucose/diabetes (yes = 1, no = 0) + 0.99 × AST/ALT ratio–0.013 × platelet (×109/L)−0.66 × albumin (g/dL). Advanced fibrosis was defined as stage 3 to 4 fibrosis.
RESULTS:  One hundred sixty-two patients (age 46 ± 10 yr, male 59%) were included in the study. Advanced fibrosis was found in 18 (11%) patients. Only 11 of 128 patients with the NAFLD fibrosis score below the proposed low cutoff point (<−1.455) were under-staged, resulting in a high negative predictive value of 91%. Only two patients exceeded the proposed high cutoff point (>0.676), but neither had advanced fibrosis. If the NAFLD fibrosis score was implemented in the Chinese population, 79% of liver biopsies could be avoided.
CONCLUSIONS:  The NAFLD fibrosis score has high negative predictive value in excluding advanced fibrosis in the Chinese population, and can reduce the burden of liver biopsy in the vast majority of cases. Since there were few cases of advanced fibrosis in this cohort, this study had limited power in validating the high cutoff point.  相似文献   
8.
The response to cardiopulmonary exercise (CPX) in patients with heart failure (HF) with normal left ventricular (LV) ejection fractions (EFs) is not well characterized. To determine if CPX testing could distinguish between patients with HF with normal EFs (>50%; i.e., diastolic HF) and those with decreased EFs (> or =50%; i.e., systolic HF), CPX responses were compared between 185 patients with systolic HF (79% men, mean age 62.6 +/- 10.9 years) and 43 with diastolic HF (54% men, mean age 67.4 +/- 9.8 years) enrolled in a phase II multicenter clinical trial. All patients were evaluated with echocardiography and a standardized CPX test as part of the trial. CPX variables, including oxygen uptake at peak exercise (peak VO(2)) and the slope of the ventilation/carbon dioxide production ratio (VE/VCO(2)), were determined and analyzed by core laboratory personnel. Echocardiographic measurements included the LV EF, the E/A ratio, filling time, cavity volumes, right ventricular function, and mitral regurgitation. Patients in the diastolic HF group tended to be older (p <0.08), with more women (p <0.006) and with greater body mass indexes (p <0.02), than those in the systolic HF group. There was no significant difference in the use of beta blockers or the incidence of coronary artery disease. Patients with diastolic HF had decreased E/A ratios (0.9 +/- 0.4 vs 1.4 +/- 1.1, p <0.02, diastolic HF vs systolic HF) and increased filling times (30.4 +/- 3.2 vs 26.5 +/- 4.7 ms, p <0.01, diastolic HF vs systolic HF). No significant differences in peak VO(2) (14.4 +/- 1.9 vs 15.6 +/- 3.2 ml/kg/min, p = 0.06, diastolic HF vs systolic HF) were observed. The VE/VCO(2) ratios for the 2 groups were abnormal and comparable (32 2 +/- 7.5 vs 34.0 +/- 8.3, p = 0.3, diastolic HF vs systolic HF). In conclusion, the CPX response in patients with diastolic HF and systolic HF is markedly abnormal and indistinguishable with regard to peak VO(2) and ventilation despite marked differences in the LV EF.  相似文献   
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OBJECTIVES: The purpose of this study was to demonstrate in patients with moderate to severe heart failure that exertional dyspnea can be alleviated by improving muscle function. BACKGROUND: Dyspnea is a frequent limiting symptom in patients with chronic heart failure (CHF). This sensation may originate from activation of receptors in the musculature rather than the lung. METHODS: To investigate whether dyspnea could be alleviated by selective changes in leg muscle function, we performed isolated lower-limb training in 17 patients with severe CHF. Eight patients learned guided imagery relaxation techniques and served as an active control group. Exercise training consisted of three months of low-level bicycle and treadmill exercise such that minute ventilation was <25 l/min. Leg calisthenics were also performed. Maximal and submaximal exercise performance, respiratory and quadriceps muscle strength and endurance and quality-of-life and dyspnea scales were measured before and after each intervention. Metabolic stress testing (VO(2)), pulmonary function tests and isokinetic strength testing were also performed. RESULTS: In the active control group, no changes in leg muscle function, pulmonary function, maximal and submaximal exercise performance or quality-of-life questionnaires were observed. In the training group, peak torque of leg flexors (pre: 39 +/- 15 ft-lb; post: 50 +/- 13 ft-lb; p < 0.002) increased and the fatigue ratio decreased, indicating improved strength and endurance of the leg muscles. Maximal inspiratory and expiratory mouth pressures and maximum voluntary ventilation were unchanged. Peak VO(2) was increased (pre:12 +/- 2.2 ml/kg/min; post: 14 +/- 2.6 ml/kg/min) as well as the duration of exercise at 70% peak VO(2) increased (pre: 11.5 +/- 3.1 min; post: 21.5 +/- 5.4 min; p < 0.003). Perceived dyspnea during the submaximal testing was decreased. Minnesota Living with Heart Failure Score, Guyatt Dyspnea Scale, and the Transitional Dyspnea Index were all improved with training (all p < 0.05). CONCLUSIONS: We concluded that improvement of limb muscle function alleviates dyspnea and improves exercise performance in patients with CHF.  相似文献   
10.
Hui CK  Lie A  Au WY  Leung YH  Ma SY  Cheung WW  Zhang HY  Chim CS  Kwong YL  Liang R  Lau GK 《Blood》2005,106(2):464-469
The long-term hepatic complications after allogeneic hematopoietic stem cell transplantation (HSCT) in hepatitis B virus (HBV) endemic area are unknown. We examined the serological and liver-related outcome of 803 consecutive patients who received allogeneic HSCTs, with a median follow-up period of 83 months (range, 0.5-155 months). Late HBV-related hepatitis occurred in 2 of the 721 hepatitis B surface antigen-negative (HBsAg-) recipients compared with 16 of the 82 HBsAg+ recipients after HSCT (0.3% vs 19.5%; P < .001 by log-rank). Liver cirrhosis developed in 8 of the 82 HBsAg+ recipients compared with none of the 721 HBsAg- recipients (9.8% vs 0%; P < .001 by log-rank). Twenty of the 31 (64.5%) HBsAg+ recipients of hematopoietic stem cells from donors with natural immunity to HBV had sustained serologic clearance of HBsAg after HSCT. Eight of the 62 recipients without sustained HBsAg clearance compared with none of the 20 recipients with sustained HBsAg clearance developed liver cirrhosis (12.9% vs 0%; P = .02 by log-rank). Our study showed that long-term hepatic complications occur in a significant proportion of HBsAg+ patients after HSCT and the incidence of liver cirrhosis is reduced in those with sustained serologic clearance of HBsAg after HSCT.  相似文献   
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