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991.
992.

Background

Frailty and acute kidney injury are independently associated with an increased risk of morbidity and mortality. The degree of frailty can be assessed by the Clinical Frailty Score (CFS). This study assessed whether an individual's CFS was associated with acute kidney injury in acute elderly medical admissions and recorded the short-term outcomes.

Methods

This was a single-center prospective observational cohort study. All patients aged ≥65 years admitted under an acute medical take over 12 nonconsecutive days were included. Patient demographics, comorbidities, baseline CFS, and renal status on admission were recorded. Outcomes of death, length of stay, and hospital re-attendance were assessed 2 weeks following admission.

Results

Of 164 patients (77 males), 19% had acute kidney injury on admission and 22% were considered severely frail. Severe frailty was associated with acute kidney injury (P = .01) and death within 2 weeks (P = .01). Two-week mortality was highest among patients with both (36%).

Conclusion

The incidence of acute kidney injury in “severely frail” acutely unwell elderly patients is significantly higher and associated with an increased short-term mortality. The CFS may be useful in acute illness to guide clinical decisions in elderly patients.  相似文献   
993.
BACKGROUND: Malignant duodenal obstruction is a common event in patients with advanced biliary tract cancer. Because bypass surgery is accompanied by significant morbidity, self-expandable metallic stents have emerged as a possible alternative for palliation. METHODS: Twenty patients with biliary tract cancer (7 gallbladder, 13 Klatskin tumors) and duodenal obstruction were treated with metallic stents at a single institution between 1999 and 2001. Survival, morbidity, and stent function were studied prospectively. The ability to eat was assessed by using a scoring system. RESULTS: Stent placement was technically successful in all patients. An additional stent was required in 6 cases (4 occlusions, 2 dislocations). Median survival was 20.5 weeks; there was no treatment-related death. Twenty-eight biliary stent exchanges were performed in 13 (65%) patients. Erosive reflux esophagitis improved in 11 of 12 (92%) cases. After 4 weeks, all 17 surviving patients tolerated soft or solid food, whereas 13 of 17 (77%) tolerated a more solid diet (p < 0.001, gastric outlet obstruction scoring system). Twelve of 17 (71%) patients gained a median of 1.5 kg of body weight (p = 0.001). The median Karnofsky scale increased from 50% to 60% in 13 of 17 (77%) patients. CONCLUSIONS: Self-expandable metallic stents are a safe, efficacious, and minimally invasive treatment option for palliation of patients with duodenal obstruction from biliary tract cancer. Technical complications can be managed endoscopically and the bile duct remains accessible for endoluminal treatment.  相似文献   
994.
Selective targeted delivery of TNFalpha to tumor blood vessels   总被引:4,自引:0,他引:4       下载免费PDF全文
We sought to enhance the selective toxicity of tumor necrosis factor alpha (TNFalpha) to permit its systemic use in cancer therapy. Because ligand-targeted therapeutics have proven successful in improving the selective toxicity of drugs, we prepared a fusion protein (L19mTNFalpha) composed of mouse TNFalpha and a high-affinity antibody fragment (L19 scFv) to the extradomain B (ED-B) domain of fibronectin, a marker of angiogenesis. L19mTNFalpha was expressed in mammalian cells, purified, and characterized. L19mTNFalpha was an immunoreactive and biologically active homotrimer. Radiolabeled L19mTNFalpha selectively targeted tumor neovasculature in tumor-bearing mice, where it accumulated selectively and persistently (tumor-to-blood ratio of the percentage of injected dose per gram [%ID/g] of 700, 48 hours from injection). L19mTNFalpha showed a greater anticancer therapeutic activity than both mTNFalpha and TN11mTNFalpha, a control fusion protein in which an antibody fragment, irrelevant in the tumor model used, substituted for L19. This activity was further dramatically enhanced by its combination with melphalan or the recently reported fusion protein L19-IL2. In conclusion, L19mTNFalpha allows concentrating therapeutically active doses of TNFalpha at the tumor level, thus opening new possibilities for the systemic use of TNFalpha in cancer therapy.  相似文献   
995.
Over the last decades, plasma exchange (PE) has been applied in the treatment of over 150 different diseases including nephrological, hematological, neurological, and rheumatological. Clinical benefit has been demonstrated in only about 40 of them and the best results were achieved in diseases with pathogenic autoimmune mechanisms. We used PE most frequently in patients with immune and autoimmune nephropathies aiming to decrease pathologically elevated antibody levels, autoantibodies and immune complexes. PE was applied in 40 patients with chronic glomerulonephritis, 29 patients with lupus nephritis, and 9 patients with Schoenlein‐Henoch nephritis. After 3 to 4 PE sessions, continuous immunosuppressive drug therapy was initiated. Significant reduction of antibody titers and immune complexes was achieved. PE was also applied in 45 plasmacytoma patients with nephropathy to reduce plasma viscosity and slow down the progression of myeloma nephropathy. The result was a significant reduction of pathologically elevated plasma viscosity and a detoxification effect. In our clinic plasma exchange procedures were performed by either centrifugal method with Haemonetics M‐30 device or by plasma filtration. An average of 1316 mL plasma was removed during a PE session. For substitution purposes donor plasma and saline solutions were used. Clinical remission was achieved in 61.3% of all patients without slowing the progression of renal failure, however.  相似文献   
996.
High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (auto-HSCT) is a new and promising approach to the treatment of multiple sclerosis (MS) patients because currently there are no effective treatment methods for this disease. In this article, we present results of a prospective clinical study of efficacy of HDIT + auto-HSCT in MS patients. The following treatment strategies were employed in the study: "early," "conventional," and "salvage/late" transplantation. Fifty patients with various types of MS were included in this study. No toxic deaths were reported among 50 MS patients; transplantation procedure was well-tolerated by the patients. The efficacy analysis was performed in 45 patients. Twenty-eight patients achieved an objective improvement of neurological symptoms, defined as at least 0.5-point decrease in the Expanded Disability Status Scale (EDSS) score as compared to the baseline and confirmed during 6 months, and 17 patients had disease stabilization (steady EDSS level as compared to the baseline and confirmed during 6 months). The progression-free survival at 6 years after HDIT + auto-HSCT was 72%. Magnetic resonance imaging data were available in 37 patients before transplantation showing disease activity in 43.3%. No active, new, or enlarging lesions were registered in patients without disease progression. In conclusion, HDIT + auto-HSCT suggests positive results in management of patients with different types of MS. Identification of treatment strategies based on the level of disability, namely "early," "conventional," and "salvage/late" transplantation, appears to be feasible to improve treatment outcomes.  相似文献   
997.
PURPOSE: This study was undertaken to determine the anal sensitivity in controls and in different patient groups and to establish factors that determine anal sensitivity. METHODS: Anorectal function tests were performed in 387 patients with different anorectal diseases. Anal sensitivity was measured in 36 controls. Anal sensitivity was measured by means of mucosal electrosensitivity (MES) using a catheter with two electrodes placed in the anal canal. A constant current (square wave stimuli 100 μsec, pulses per second) was increased stepwise from 1 to 20 mAmp until the threshold sensation was reached. Other tests used were anal manometry (maximum basal pressure, maximum squeeze pressure, rectal compliance (maximum rectal volume and pressure), endosonography (submucosal thickness), defects and thickness of internal and external sphincter), electromyography (maximum contraction pattern, Grade 1 (solitary contractions) to Grade 4 (interference pattern)), and pudendal nerve terminal motor latency. Multiple regression analysis was performed. It was postulated that age, local conditions (anal scars, anal fissures, hemorrhoids, mucosal prolapse, proctitis, sphincter thickness and defects, and submucosal thickness), and neurologic factors could influence anal sensitivity. RESULTS: Controls had an MES of 3.4±1.7. MES was significantly increased compared with controls in patients with fecal incontinence, soiling, hemorrhoids, mucosal prolapse, constipation, anal scars, anal surgery, and sphincter defects; patients with fecal incontinence had the highest MES (6.7±4.3;P <0.0001). Patients with anal fissures and proctitis showed no differences compared with controls. MES correlated significantly with age (R =0.29), maximum basal pressure (R =?0.29), maximum squeeze pressure (R =?0.32), submucosal thickness (R =0.19), maximum contraction pattern (R =?0.39), single-fiber electromyography (R =0.39), and maximum rectal volume and pressure (0.14). Multiple regression analysis showed that age, internal sphincter defects, and submucosal thickness significantly influenced anal sensitivity, but explained only 10 percent of the variance. CONCLUSION: Anal sensitivity is diminished in all patients with anorectal diseases except for anal fissures and proctitis. There are correlations with other anorectal function tests. Anal sensitivity is determined for 10 percent by age, internal sphincter defects, and thickness of the submucosa. Anal sensitivity measurement, therefore, has limited clinical value and should be used in conjunction with other tests in a research setting.  相似文献   
998.

Background

Biofilms may contribute to refractory chronic rhinosinusitis (CRS), as they lead to antibiotic resistance and failure of effective clinical treatment. l ‐Methionine is an amino acid with reported biofilm‐inhibiting properties. Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator with mild antimicrobial activity via inhibition of bacterial DNA gyrase and topoisomerase IV. The objective of this study was to evaluate whether co‐treatment with ivacaftor and l ‐methionine can reduce the formation of Pseudomonas aeruginosa biofilms.

Methods

P aeruginosa (PAO‐1 strain) biofilms were studied in the presence of l ‐methionine and/or ivacaftor. For static biofilm assays, PAO‐1 was cultured in a 48‐well plate for 72 hours with stepwise combinations of these agents. Relative biofilm inhibitions were measured according to optical density of crystal violet stain at 590 nm. Live/dead assays (BacTiter‐Glo? assay, Promega) were imaged with laser scanning confocal microscopy. An agar diffusion test was used to confirm antibacterial effects of the drugs.

Results

l ‐Methionine (0.5 μM) significantly reduced PAO‐1 biofilm mass (32.4 ± 18.0%; n = 4; p < 0.001) compared with controls. Low doses of ivacaftor alone (4, 8, and 12 μg/mL) had no effect on biofilm formation. When combined with ivacaftor (4 μg/mL), a synergistic anti‐biofilm effect was noted at 0.05 μM and 0.5 μM of l ‐methionine (two‐way analysis of variane, p = 0.0415) compared with corresponding concentrations of l ‐methionine alone.

Conclusion

Ivacaftor enhanced the anti‐biofilm activity of l ‐methionine against the PAO‐1 strain of P aeruginosa. Further studies evaluating the efficacy of ivacaftor/l ‐methionine combinations for P aeruginosa sinusitis are planned.
  相似文献   
999.
Reverse genetics is a powerful tool for understanding gene functions and their interactions in the mosquito innate immunity. We took the transgenic approach, in combination with the RNA interference (RNAi) technique, to elucidate the role of mosquito REL1, a homolog of Drosophila Dorsal, in regulation of Toll immune pathway in the mosquito Aedes aegypti. By transforming the mosquitoes with DeltaREL1-A or a double-stranded RNA construct of REL1 driven by the female fat body-specific vitellogenin (Vg) promoter with the pBac[3xP3-EGFP, afm] vector, we generated two different transgenic mosquito strains, one with overexpressed AaREL1 and the second with AaREL1 knockdown. Both strains had a single copy of the respective transgene, and the expression in both transgenic mosquitoes was highly activated by blood feeding. Vg-DeltaREL1-A transgenic mosquitoes activate Toll immune pathway in the fat body by blood feeding. The overexpression of both isoforms, AaREL1-A and AaREL1-B, in Vg-DeltaREL1-A transgenic mosquitoes resulted in the concomitant activation of Aedes Sp?tzle1A and Serpin-27A, independent of septic injury. The same phenotype was observed in the mosquitoes with RNAi knockdown of an Aedes homolog to Drosophila cactus, an IkappaB inhibitor of Drosophila Toll pathway. The effect of the transgenic RNAi knockdown of AaREL1 on mosquito innate immunity was revealed by increased susceptibility to the entomopathogenic fungus Beauveria bassiana and the reduced induction of Spz1A and Serpin-27A gene expression after fungal challenge. These results have proven that AaREL1 is a key downstream regulator of Toll immune pathway in the mosquito A. aegypti.  相似文献   
1000.
Isolated GH deficiency (IGHD) is characterized by genetic heterogeneity, both in familial and sporadic cases. To determine if this statement can be applied to the Russian population, we performed screening for mutations in the GH-1 gene in children living in Russia with IGHD. Twenty-eight children from 26 families with total IGHD were studied. DNA fragments, covering each of four (2-5) exons of GH-1 were amplified using PCR. Single-strand conformation polymorphism analysis followed by direct DNA sequencing identified five heterozygous mutations of splicing in intron 2, intron 3, and exon 4 of GH-1; three of them were not previously reported. We concentrated here on dominant-negative mutations causing IGHD type II, which were as follows: 1) A>T transversion of the second base of the 3'-acceptor splice site of intron 2 (IVS2 -2A>T); 2) T>C transition of the second base of the 5'-donor splice site of intron 3 (IVS3 +2T>C); 3) G>A transition of the first base of the 5'-donor splice site of intron 3 (IVS3 +1G>A). Our data indicate allelic heterogeneity of IGHD type II (IGHD II). However, all mutations in Russian IGHD II patients affect splicing, a striking difference from the mutation spectrum of other IGHD forms. The IVS2 -2A>T mutation is the first identified mutation in intron 2 of GH-1. The 5'-donor splice site of intron 3 of GH-1 is a mutational hot spot, and the IVS3 +1G>A mutation can be considered to be a common molecular defect in IGHD II in Russian patients.  相似文献   
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