Acquired Idiopathic Stiffness After Contemporary Total Knee Arthroplasty: Incidence,Risk Factors,and Results Over 25 Years

BackgroundAcquired idiopathic stiffness (AIS) remains a common failure mode of contemporary total knee arthroplasties (TKAs). The present study investigated the incidence of AIS and manipulation under anesthesia (MUA) at a single institution over time, determined outcomes of MUAs, and identified risk factors associated with AIS and MUA.MethodsWe identified 9771 patients (12,735 knees) who underwent primary TKAs with cemented, modular metal-backed, posterior-stabilized implants from 2000 to 2016 using our institutional total joint registry. Mean age was 68 years, 57% were female, and mean body mass index was 33 kg/m². Demographic, surgical, and comorbidity data were investigated via univariate Cox proportional hazard models and fit to an adjusted multivariate model to access risk for AIS and MUA. Mean follow-up was 7 years.ResultsDuring the study period, 456 knees (3.6%) developed AIS and 336 knees (2.6%) underwent MUA. Range of motion (ROM) increased a mean of 34° after the MUA; however, ROM for patients treated with MUA was inferior to patients without AIS at final follow-up (102° vs 116°, P < .0001). Significant risk factors included younger age (HR 2.3, P < .001), increased tourniquet time (HR 1.01, P < .001), general anesthesia (HR 1.3, P = .007), and diabetes (HR 1.5, P = .001).ConclusionAcquired idiopathic stiffness has continued to have an important adverse impact on the outcomes of a subset of patients undergoing primary TKAs. When utilized, MUA improved mean ROM by 34°, but patients treated with MUA still had decreased ROM compared to patients without AIS. Importantly, we identified several significant risk factors associated with AIS and subsequent MUA.Level of EvidenceLevel III, retrospective comparative study.     

STAG2 as a prognostic biomarker in low-grade non-muscle invasive bladder cancer

ObjectiveImprovements to bladder cancer risk stratification guidelines are needed to better tailor post-operative surveillance and adjuvant therapy to individual patients. We previously identified STAG2 as a commonly mutated tumor suppressor gene in bladder cancer and an independent predictor of progression in NMIBC. Here we test the value of combining STAG2 immunostaining with other risk stratification biomarkers in NMIBC, and as an individual biomarker in MIBC.Materials and MethodsSTAG2 immunohistochemistry was performed on a progressor-enriched cohort of tumors from 297 patients with NMIBC, and on tumors from 406 patients with MIBC from Aarhus University Hospital in Denmark. Survival analysis was performed using Kaplan-Meier survival analysis, the log rank test, and Cox proportional hazards models.ResultsSTAG2-negative low-grade NMIBC tumors were 2.5 times less likely to progress to muscle invasion than STAG2-positive low-grade NMIBC tumors (Log-rank test, P = 0.008). In a composite group of patients with AUA intermediate and high-risk NMIBC tumors, STAG2-negative tumors were less likely to progress (Log-rank test, P = 0.02). In contrast to NMIBC, we show that STAG2 is not useful as a prognostic biomarker in MIBC.ConclusionsSTAG2 immunostaining can be used to subdivide low-grade NMIBC tumors into two groups with substantially different risks of disease progression. Furthermore, STAG2 immunostaining may be useful to enhance NMIBC risk stratification guidelines, though larger cohorts are needed to solidify this conclusion in individual risk groups. STAG2 is not useful as a biomarker in MIBC. Further study of the use of STAG2 immunostaining as a biomarker for predicting the clinical behavior in NMIBC is warranted.     

Perturbation of the sarcolemmal membrane in isoproterenol-induced myocardial injury of the rat. Permeability and freeze-fracture studies in vivo and in vitro.

The mechanism whereby cardiotoxic doses of isoproterenol (ISO) induces early permeability alteration of the sarcolemmal membrane is unknown; both beta-receptor overstimulation and direct toxic effect of ISO oxidation products have been implicated. There has been no morphologic observation, furthermore, on the structural basis of permeability alteration during this process. The purpose of the present study was to compare the morphology of cardiocyte injury induced by ISO and oxidized ISO (ISO-O2) and to visualize perturbation of the sarcolemma correlating with the leaky membrane. The authors studied the left ventricular myocardium of rats 10 and 60 minutes after subcutaneous administration of 85 mg/kg ISO and isolated perfused rat hearts exposed for 10 minutes either to ISO or ISO-O2 in a dose of 100 mg/l (10(-4) M) to determine the permeability of the sarcolemmal membrane using the extracellular diffusion tracer horseradish peroxidase (HRP) by light and thin section electron microscopy, the morphology of the sarcolemmal membrane by means of freeze-fracture electron microscopy, and the density of intramembrane particles (IMP) in the sarcolemmal membrane by planimetry using freeze-fracture electron microscopy. In in vivo rat hearts both 10 and 60 minutes after ISO and in vitro (isolated perfused) rat hearts exposed to either ISO or ISO-O2 for 10 minutes, HRP labeled the sarcoplasm of focally located cardiocytes implicating leakiness of the sarcolemmal membrane. HRP positive cardiocytes (with the exception of the in vivo 10 minute group) showed characteristic features of contraction band necrosis (both on light and thin-section electron microscopy) in all groups. Freeze-fracture electron microscopy of sarcolemmal protoplasmic (P) membrane faces revealed two populations of cardiocytes in all groups. P-membrane faces in one population of cardiocytes appeared as in the control. In the other population of cardiocytes, P-membrane faces showed irregular tears. Planimetry demonstrated a significant decrease of IMP numerical densities in P-membrane faces with tears in the in vivo 10 minute group and both with or without tears in the in vivo 60 minutes group and the in vitro groups compared with the control values. Furthermore, with the exception of the 10 minute in vivo group, IMP densities significantly decreased in sarcolemmal membranes with tears compared with those without tears in all experimental groups. These observations are consistent with the view that catecholamine induced myocardial injury is, at least partly, related to the direct toxic effect of catecholamine oxidation products on the sarcolemmal membrane.(ABSTRACT TRUNCATED AT 400 WORDS)     

恶性肿瘤患者血清与尿液中一氧化氮含量测定

0 引言一氧化氮（Nitric oxide,NO）是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性［1］,为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.     

Population-based dietary intakes and tap water concentrations for selected elements in the EPA region V National Human Exposure Assessment Survey (NHEXAS).

A National Human Exposure Assessment Survey (NHEXAS) field study was performed in U.S. Environmental Protection Agency (EPA) Region V, providing population-based exposure distribution data for selected elements in several personal, environmental, and biological media. Population distributions are reported for the 11 elements that were measured in water and dietary samples. Dietary intakes and home tap water concentrations of lead, arsenic, and cadmium were further examined for intermedia associations, for differences between dietary exposure for adults and children, and to estimate the proportion of the population above health-based reference values (dietary) or regulatory action levels or maximum contaminant levels (water). Water lead and arsenic concentrations were significantly associated with dietary intake. Intake of all elements was higher from solid foods than from liquid foods (including drinking water). Dietary intakes of Pb, As, and Cd were greater than those calculated for intake from home tap water or inhalation on a microg/day basis. Median dietary intakes for the Region V population for Pb, As, and Cd were 0.10, 0.13, and 0.19 microg/kg bw/day, respectively. While Pb, As, and Cd concentrations in the foods consumed by 0 to 6-year-old children were similar to or lower than those for adults, dietary intakes calculated on a body weight basis were 1.5 to 2.5 times higher for young children. Intrapersonal intake differences accounted for most of the variance in short-term (daily) dietary intakes for Pb and As, while interpersonal differences accounted for more of the intake variance for Cd. Only small percentages of the population exceeded health-based intake reference values or concentrations equal to regulatory levels in water for Pb, As, and Cd.     

Effects of the solvents on bond strength of resin bonded porcelain

Clinical trials of porcelain veneers for chairside colour modifications may require the use of a trial resin with various colours of tints. The bond strength effects of four different solvents used for removal of trial resin from etched porcelain specimens were investigated. Fifty-six porcelain specimens were fabricated, flattened by a metallurgically standard method, etched with hydrofluoric acid and silane treated. The specimens were divided into four groups at random. The trial resin material was cleaned with different solvents prior to bonding of a dual cure resin composite button. After bonding the specimens were stored in water at 37 degrees C for 7 days. Shear bond strength results were as follows: acetone (control) group, 12.9+/-2.9 MPa; ethanol group, 15.1+/-4.6 MPa; methanol group, 11.5+/-2.9 MPa; methylene chloride group, 11.3+/-2.4 MPa. No significant differences were measured (ANOVA, P>0.05). The results indicated that the resin-porcelain bond strengths were not affected by the type of solvent used to remove trial resin. This procedure is recommended for clinical cases when resin composite is used for the try-in of etched porcelain bonded restorations.     

Lung cancer in patients aged 50 years and younger: clinical characteristics, treatment details and outcome

Younger patients (< or = 50 years of age) develop lung cancer. Many series report 5-10% of all cases occurring in younger patients. Outcome, inspite of treatment, is universally poor. Females and adenocarcinomas are over-represented and the aetiology for such an early-age presentation is unclear. The aims of this retrospective study were to review the clinical characteristics, treatment details and outcome of patients aged 50 years or younger diagnosed with lung cancer (small cell and non-small cell). Over a period of 34 months, 497 lung cancer patients were treated at the Liverpool Hospital Cancer Therapy Centre. Thirty-seven (7.4%) patients aged less than or equal to 50 years were identified. The median age at diagnosis was 44 years (range 32-49 years) in 20 females and 17 males. Adenocarcinoma was the predominant histological subtype (32%). No referred patient had stage I/II disease. Almost 90% of patients were smokers. Median survival following diagnosis was 12 months (range, 9 days-68 months) with 70% having died by the close of study. The clinical characteristics and outcome of young patients in our study were comparable to other similar series.     

Pelvic discontinuity in revision total hip arthroplasty

BACKGROUND: Pelvic discontinuity is a distinct form of bone loss, occurring in association with total hip arthroplasty, in which the superior aspect of the pelvis is separated from the inferior aspect because of bone loss or a fracture through the acetabulum. The purpose of this study was to describe the population of patients who are at risk for this condition, to identify the characteristic radiographic features associated with it, and to report the results of revision total hip arthroplasty for the treatment of pelvic discontinuity. METHODS: The cases of all twenty-seven patients (thirty-one hips) who were identified as having a pelvic discontinuity at the time of a reoperation for a failed hip arthroplasty at one institution were reviewed retrospectively, and demographic information was collected. The preoperative radiographs and the operative notes were reviewed, and the postoperative results and complications were recorded. RESULTS: Pelvic discontinuity was identified in association with thirty-one (0.9 percent) of 3505 acetabular revisions. The mean age of the patients was sixty-one years (range, thirty-eight to eighty years). Twenty-eight hips were in women, and three were in men. Women (p < 0.001) and patients who had rheumatoid arthritis (p = 0.003) had a significantly increased risk of pelvic discontinuity. The radiographic findings included a visible fracture line through the anterior and posterior columns, medial translation of the inferior aspect of the hemipelvis relative to the superior aspect (seen as a break in Kohler's line), and rotation of the inferior aspect of the hemipelvis relative to the superior aspect (seen as asymmetry of the obturator rings) on a true anteroposterior radiograph. Two patients died within two years after the revision, and two had a resection arthroplasty for the treatment of the pelvic discontinuity; thus, twenty-seven hips were reconstructed and were eligible for follow-up at least two years after the operation. A number of different methods were used for reconstruction, but the results were best in patients who did not have severe segmental acetabular bone loss (type IVa [a satisfactory result in three of three hips]) and poorer in those who had severe segmental or combined segmental and cavitary bone loss (type IVb [a satisfactory result in ten of nineteen hips]) and in those who previously had been treated with irradiation to the pelvis (type IVc [a satisfactory result in three of five hips]). Nine of the twenty-seven hips needed another operation: four, because of aseptic loosening of the acetabular component; four, because of recurrent dislocation; and one, because of deep infection. Excluding three hips that were revised early because of infection or dislocation, a mechanically stable construct (that is, a stable socket and a possibly or definitely healed discontinuity) was obtained in seventeen of twenty-four hips. CONCLUSIONS: Pelvic discontinuity is uncommon, and treatment is associated with a high rate of complications. For hips with type-IVa bone loss and selected hips with type-IVb defects, in which a socket inserted without cement can be satisfactorily supported by native bone, we prefer to use a posterior column plate to stabilize the pelvis and a porous-coated socket inserted without cement. For most hips with type-IVb and type-IVc bone loss, we prefer to use particulate bone graft or a single structural bone graft protected with an antiprotrusion cage.