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91.
Skeletal anabolism with PTH is achieved through daily injections that result in brief exposure to the peptide. We hypothesized that similar anabolic effects could be achieved with less frequent but more sustained exposures to PTH. A PTH-Fc fusion protein with a longer half-life than PTH(1-34) increased cortical and cancellous BMD and bone strength with once- or twice-weekly injections. INTRODUCTION: The anabolic effects of PTH are currently achieved with, and thought to require, daily injections that result in brief exposure to the peptide. We hypothesized that less frequent but more sustained exposures to PTH could also be anabolic for bone, provided that serum levels of PTH were not constant. MATERIALS AND METHODS: PTH(1-34) was fused to the Fc fragment of human IgG1 to increase the half-life of PTH. Skeletal anabolism was examined in mice and rats treated once or twice per week with this PTH-Fc fusion protein. RESULTS: PTH-Fc and PTH(1-34) had similar effects on PTH/PTHrP receptor activation, internalization, and signaling in vitro. However, PTH-Fc had a 33-fold longer mean residence time in the circulation of rats compared with that of PTH(1-34). Subcutaneous injection of PTH-Fc once or twice per week resulted in significant increases in bone volume, density, and strength in osteopenic ovariectomized mice and rats. These anabolic effects occurred in association with hypercalcemia and were significantly greater than those achievable with high concentrations of daily PTH(1-34). PTH-Fc also significantly improved cortical bone volume and density under conditions where daily PTH(1-34) did not. Antiresorptive co-therapy with estrogen further enhanced the ability of PTH-Fc to increase bone mass and strength in ovariectomized rats. CONCLUSIONS: These results challenge the notion that brief daily exposure to PTH is essential for its anabolic effects on cortical and cancellous bone. PTH-derived molecules with a sustained circulating half-life may represent a powerful and previously undefined anabolic regimen for cortical and cancellous bone.  相似文献   
92.
OBJECTIVE: Sleeve lobectomy is a widely accepted procedure for central tumors for which the alternative is pneumonectomy. The purpose of this study is to assess operative mortality, morbidity, and long-term results of sleeve lobectomies performed for non-small cell lung carcinoma (NSCLC). METHODS: A retrospective review of 218 patients who underwent sleeve lobectomy for NSCLC between 1981 and 2005 was undertaken. There were 186 (85%) men and 32 women with a mean age of 61.9 years (range, 19-82 years). Eighty patients (36.6%) had a preoperative contraindication to pneumonectomy. Right upper lobectomy was the most common operation (45.4%). Vascular sleeve resection was performed in 28 patients (12.8%) and was commonly associated with left upper lobectomy (n=20; 9.1%; p=0.0001). The histologic type was predominantly squamous cell carcinoma (n=164; 75%), followed by adenocarcinoma (n=46; 21%). Resection was incomplete in nine (4.1%) patients. RESULTS: There were nine operative deaths; the operative mortality and the morbidity rates were 4.1% and 22.9%, respectively. A total of 14 (6.4%) patients presented with bronchial anastomotic complications: two were fatal postoperatively, seven patients required reoperation, three required a stent insertion, and two were managed conservatively. Multivariate analysis showed that compromised patients (p=0.001), current smoking (p=0.01), right sided resections (p=0.003), bilobectomy (p=0.03), squamous cell carcinoma (p=0.03), and presence of N1 or N2 disease (p=0.01) were risk factors for mortality and morbidity. Follow-up was complete in 208 patients (95.4%). Overall 5-year and 10-year survival rates were 53% and 28.6%, respectively. After complete resection, recurrence was local in 10 patients, mediastinal in 20, and distant in 25. By multivariate analysis, two factors significantly and independently influenced survival: nodal status (N0-N1 vs N2; p=0.01) and the stage of the lung cancer (stage I-II vs III, p=0.02). CONCLUSIONS: For patients with NSCLC, sleeve lobectomy achieves local tumor control, even in patients with preoperative contraindication to pneumonectomy and is associated with low mortality and bronchial anastomotic complication rates. Postoperative complications are higher in compromised patients, smokers, N disease, right sided resections, bilobectomies, and squamous cell cancers. The presence of N2 disease and stage III significantly worsen the prognosis.  相似文献   
93.
Atypical lipomatous tumor/well-differentiated liposarcomas and dedifferentiated liposarcomas are characterized by the amplification of MDM2 and CDK4 genes. To evaluate the accuracy of fluorescence in situ hybridization (FISH) analysis in the differential diagnosis of adipose tissue tumors, we investigated MDM2-CDK4 status by FISH, real-time polymerase chain reaction (PCR) [quantitative PCR (Q-PCR)] and immunohistochemistry (IHC) in a series of 200 adipose tumors. First, we evaluated MDM2-CDK4 amplification and expression in a series of 94 well-defined adipose tissue tumors. Results showed that FISH was interpretable in 45 of 50 cases (90%), and was more specific and sensitive than Q-PCR and IHC. We then used the same techniques as complementary diagnostic tools in a series of 106 adipose and soft tissue tumors of unclear diagnosis to distinguish between (i) lipomas and atypical lipomatous tumor/well-differentiated liposarcomas, (ii) malignant undifferentiated tumors and dedifferentiated liposarcomas, and (iii) a variety of benign tumors and liposarcomas. Our results indicate that although helpful, IHC alone is often insufficient to solve diagnostic problems. FISH and Q-PCR methods gave concordant results and were equally informative in most cases. However, the proportion of noninterpretable cases was slightly higher with FISH than with Q-PCR. When tumor cells represented a minor component of the tumor tissue, such as with inflammatory tumors, FISH was more powerful than Q-PCR by allowing visualization of individual cells. In conclusion, we recommend that the evaluation of MDM2-CDK4 amplification using FISH or Q-PCR be used to supplement IHC analysis when diagnosis of adipose tissue tumors is not possible based on clinical and histologic information alone.  相似文献   
94.
PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment.  相似文献   
95.

Purpose

Symptomatic adjacent segment disease (ASD) has been reported to occur in up to 27 % of lumbar fusion patients. A previous study identified patients at risk according to the difference of pelvic incidence and lordosis. Patients with a difference between pelvic incidence and lumbar lordosis >15° have been found to have a 20 times higher risk for ASD. Therefore, it was the aim of the present study to investigate forces acting on the adjacent segment in relation to pelvic incidence–lumbar lordosis (PILL) mismatch as a measure of spino-pelvic alignment using rigid body modeling to decipher the underlying forces as potential contributors to degeneration of the adjacent segment.

Methods

Sagittal configurations of 81 subjects were reconstructed in a musculoskeletal simulation environment. Lumbar spine height was normalized, and body and segmental mass properties were kept constant throughout the population to isolate the effect of sagittal alignment. A uniform forward/backward flexion movement (0°–30°–0°) was simulated for all subjects. Intervertebral joint loads at lumbar level L3–L4 and L4–L5 were determined before and after simulated fusion.

Results

In the unfused state, an approximately linear relationship between sagittal alignment and intervertebral loads could be established (shear: 0° flexion r = 0.36, p < 0.001, 30° flexion r = 0.48, p < 0.001; compression: 0° flexion r = 0.29, p < 0.01, 30° flexion r = 0.40, p < 0.001). Additionally, shear changes during the transition from upright to 30° flexed posture were on average 32 % higher at level L3–L4 and 14 % higher at level L4–L5 in alignments that were clinically observed to be prone to ASD. Simulated fusion affected shear forces at the level L3–L4 by 15 % (L4–L5 fusion) and 23 % (L4–S1 fusion) more for alignments at risk for ASD.

Conclusion

Higher adjacent segment shear forces in alignments at risk for ASD already prior to fusion provide a mechanistic explanation for the clinically observed correlation between PILL mismatch and rate of adjacent segment degeneration.  相似文献   
96.
There are limited clinical data regarding prolonged‐release tacrolimus (PR‐T) use in pediatric transplant recipients. This Phase 2 study assessed the efficacy and safety of PR‐T in stable pediatric kidney, liver, and heart transplant recipients (aged ≥5 to ≤16 years) over 1 year following conversion from immediate‐release tacrolimus (IR‐T), on a 1:1 mg total‐daily‐dose basis. Endpoints included the incidence of acute rejection (AR), a composite endpoint of efficacy failure (death, graft loss, biopsy‐confirmed AR, and unknown outcome), and safety. Tacrolimus dose and whole‐blood trough levels (target 3.5–15 ng/ml) were also evaluated. Overall, 79 patients (kidney, n = 48; liver, n = 29; heart, n = 2) were assessed. Following conversion, tacrolimus dose and trough levels remained stable; however, 7.6–17.7% of patients across follow‐up visits had trough levels below the target range. Two (2.5%) patients had AR, and 3 (3.8%) had efficacy failure. No graft loss or deaths were reported. No new safety signals were identified. Drug‐related treatment‐emergent adverse events occurred in 28 patients (35.4%); most were mild, and all resolved. This study suggests that IR‐T to PR‐T conversion is effective and well tolerated over 1 year in pediatric transplant recipients and highlights the importance of therapeutic drug monitoring to maintain target tacrolimus trough levels.  相似文献   
97.
98.
BackgroundThe prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in cystic fibrosis (CF) patients has increased and MRSA seems to be associated with a poorer prognosis. The aim of this study was to assess the prevalence and clinical consequences of MRSA and methicillin-susceptible Staphylococcus aureus (MSSA), associated or not associated with Pseudomonas aeruginosa (PA).MethodsIn a retrospective study on 419 sputum producer patients (293 adults and 126 children > 7 years of age), we recorded patient characteristics, lung function, nutritional status, IV antibiotics and hospitalisations, the presence of SA and/or PA and FEV1 decline over 2 years.ResultsSA was found in 72% of the patients: MSSA in 68.2% of children and 48.8% of adults; MRSA in 17.5% of children and 17.8% of adults. Sixty percent of MRSA patients and 60.4% of MSSA patients also harboured PA. The rate of deterioration of clinical status of the various groups, as assessed from respiratory function, IV antibiotic courses and hospitalisations, increased in the order: no SA/no PA, MSSA alone, MRSA alone, MSSA/PA, MRSA/PA, and PA alone. Nutritional status did not differ between groups. Results were roughly similar for children and adults. The yearly FEV1 decline was significantly higher only for MRSA/PA patients (p = 0.03) compared to no SA/no PA patients.ConclusionClinical condition of CF patients with MSSA only or MRSA only appeared similar, whereas MRSA/PA patients had more severe respiratory function than MSSA/PA patients. In CF patients, MRSA might be more deleterious than MSSA only when associated with PA.  相似文献   
99.

Background

Minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) are the most common causes of idiopathic nephrotic syndrome (INS). We have evaluated the reliability of urinary neutrophil-gelatinase-associated lipocalin (uNGAL), urinary alpha1-microglobulin (uα1M) and urinary N-acetyl-beta-D-glucosaminidase (uβNAG) as markers for differentiating MCD from FSGS. We have also evaluated whether these proteins are associated to INS relapses or to glomerular filtration rate (GFR).

Methods

The patient cohort comprised 35 children with MCD and nine with FSGS; 19 healthy age-matched children were included in the study as controls. Of the 35 patients, 28 were in remission (21 MCD, 7 FSGS) and 16 were in relapse (14 MCD, 2 FSGS). The prognostic accuracies of these proteins were assessed by receiver operating characteristic (ROC) curve analyses.

Results

The level of uNGAL, indexed or not to urinary creatinine (uCreat), was significantly different between children with INS and healthy children (p?=?0.02), between healthy children and those with FSGS (p?=?0.007) and between children with MCD and those with FSGS (p?=?0.01). It was not significantly correlated to proteinuria or GFR levels. The ROC curve analysis showed that a cut-off value of 17 ng/mg for the uNGAL/uCreat ratio could be used to distinguish MCD from FSGS with a sensitivity of 0.77 and specificity of 0.78. uβNAG was not significantly different in patients with MCD and those with FSGS (p?=?0.86). Only uα1M, indexed or not to uCreat, was significantly (p?<?0.001) higher for patients in relapse compared to those in remission.

Conclusions

Our results indicate that in our patient cohort uNGAL was a reliable biomarker for differentiating MCD from FSGS independently of proteinuria or GFR levels.  相似文献   
100.

Background

Focal therapy (FT) for prostate cancer (PCa) seems to be part of a natural evolution in the quest to improve the management of early organ-confined disease.

Objective

To assess the morbidity of the initial experience of FT in a tertiary referral center for PCa management.

Design, setting, and participants

From 2009 to 2011, a total of 1213 patients with clinically localized PCa were treated at our institution. Of these patients, 547 were considered to have indolent disease according to the D’Amico criteria for low-risk disease plus unilateral disease with a maximum of three positive biopsies. A total of 106 patients underwent FT using high-intensity focused ultrasonography (HIFU), brachytherapy, cryotherapy, or vascular-targeted photodynamic therapy (VTP).

Outcome measurements and statistical analysis

Complications were prospectively recorded and graded according to the Clavien-Dindo scale. Data were prospectively collected and retrospectively analyzed.

Results and limitations

This study included 106 patients, median age 66.5 yr (interquartile range [IQR]): 61–73), who had a prostate hemiablation; 50 patients (47%) had cryotherapy, 23 patients (22%) had VTP, 21 patients (20%) received HIFU, and 12 patients (11%) had brachytherapy. The median prostate-specific antigen (PSA) level was 6.1 ng/ml (IQR: 5–8.1), all the patients had a biopsy Gleason score of 6, and the median prostate weight was 43 g (IQR: 33–55). The median International Prostate Symptom Score was 6 (IQR: 3–10), and the median International Index of Erectile Function score was 20 (IQR: 15–23). After treatment, the median PSA at 3, 6, and 12 mo was 3.1 2.9, and 2.7 ng/ml (IQR: 2–5.1, 1.1–4.7, and 1–4.4), respectively. Thirteen percent of the patients experienced treatment-related complications. There were 11 minor medical complications (10 grade 1 complications and 1 grade 2 complication), 2 grade 3 complications, and no grade 4 or higher complications.

Conclusions

FT for a highly selected population with PCa is feasible and had an acceptable morbidity with <2% major complications.  相似文献   
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