Orthopedic surgery residents' study habits and performance on the orthopedic in-training examination

The Orthopaedic In-Training Examination (OITE) is a tool used by residency directors to evaluate a resident's fund of orthopedic knowledge. In this study, we correlated resident study habits and preparation tools with performance on the OITE. Data analysis indicated statistically significant correlations between successful OITE performance and frequent review of current orthopedic journals (Journal of Bone and Joint Surgery-American Edition, r = .6, P < .001; Journal of the American Academy of Orthopaedic Surgeons, r = .36, P = .02), daily orthopedic reading (r = .34, P = .03), increased preparation time for OITE (r = .31, P = .04), and more hours committed to studying (r = .37, P = .01). In addition, residents who emphasized prior OITEs and self-assessment examinations when preparing had higher scores (r = .53, P < .001, and r = .64, P < .001, respectively). Our study results show that several factors, including structured study habits and use of specific study materials, contribute to residents' successful OITE performance. Adaptation of these findings by current orthopedic residents may have a positive impact on OITE performance.     

Hypoxia-induced resistance to anticancer drugs is associated with decreased senescence and requires hypoxia-inducible factor-1 activity

Hypoxia in solid tumors is associated with the development of chemoresistance. Although many studies have focused on the effect of hypoxia on drug-induced apoptosis, the effect of nonapoptotic pathways on hypoxia-induced drug resistance has not been previously investigated. Here, we determined the effects of hypoxia on multiple forms of drug-induced death in human MDA-MB-231 breast carcinoma cells. Clonogenic assays showed that preexposure to hypoxia leads to resistance to various classes of chemotherapeutic agents, including anthracyclines (daunorubicin and doxorubicin), epipodophyllotoxins (etoposide), and anthracenediones (mitoxantrone). Results revealed a high degree of heterogeneity in nuclear and cytoplasmic alterations in response to acute drug exposure; however, the majority of exposed cells displayed morphologic and biochemical changes consistent with drug-induced senescence. Hypoxia decreased only the proportion of cells in the senescent population, whereas the small proportion of cells exhibiting features of apoptosis or mitotic catastrophe were unaffected. Similar results were obtained with human HCT116 colon carcinoma cells, indicating that the protective effect of hypoxia on drug-induced senescence is not unique to MDA-MB-231 cells. Treatment of MDA-MB-231 cells with small interfering RNA targeting the alpha-subunit of hypoxia-inducible factor-1 (HIF-1), a key regulator of cellular adaptations to hypoxia, prevented hypoxia-induced resistance. HIF-1alpha small interfering RNA also selectively abolished the hypoxia-induced changes in the senescent population, indicating that the increased survival was due to protection against drug-induced senescence. These results support a requirement for HIF-1 in the adaptations leading to drug resistance and reveal that decreased drug-induced senescence is also an important contributor to the development of hypoxia-induced resistance.     

Osteoarthritis of the ankle: the role of arthroplasty

Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis. The ankle joint has unique, complex anatomic and biomechanical characteristics that must be considered in a successful total ankle arthroplasty prosthesis. Initial designs from the 1960s to the 1970s had many failures. Current designs use two or three components, and recent reports on total ankle arthroplasty show consistent good to excellent intermediate clinical results, with up to 90% decreased pain and high patient satisfaction. The follow-up time of these studies is limited, however, and long-term studies with 10- to 15-year follow-ups are needed. Also, a wide variety of complications has been reported, including osteomyelitis and osteolysis. To limit the number of complications and improve clinical outcome of total ankle arthroplasty, careful patient selection and surgeon experience are important.     

Characteristics of patients hospitalized with acute decompensated heart failure who are referred for hospice care

BACKGROUND: Hospice is a potential option for patients with end-stage heart failure whose symptoms and clinical status have progressed despite maximal medical therapy. However, little is known about hospice referral practices when patients are admitted because of acute decompensated heart failure. METHODS: Data from the Acute Decompensated Heart Failure Registry (ADHERE) were analyzed from October 1, 2001, to December 31, 2005, accounting for 182 898 patient episodes with known disposition from 307 hospitals. Demographic data, clinical characteristics, and medical management were compared in the group discharged to hospice vs patients discharged to home or to intermediate-care facilities. Hospitals, stratified by frequency of discharge of patients to hospice, were evaluated for adherence to performance measures. Temporal trends according to discharge category were analyzed using analysis of variance, and predictors of hospice referral were determined by multivariate analysis. RESULTS: The hospice cohort composed 1.6% (n = 3010) of the total sample. Patients referred to hospice were generally older, more likely to have been admitted because of antecedent heart failure in the preceding 6 months, more likely to receive intravenous inotropic therapy, less likely to receive angiotensin-converting enzyme inhibitors, and less likely to undergo a procedure (eg, dialysis or cardiac catheterization) during the hospitalization. The median rate of hospice referral increased from 0.8% in 2001 to 1.3% in 2005 (P < .008). Hospitals in the upper quartile of hospice referrals had comparable or higher rates of adherence to quality indicators for heart failure than did hospitals in the lowest quartile. Variables obtained at admission that were associated with hospice referral included older age (per 10-year increment; odds ratio [OR], 1.63; 95% confidence interval [CI], 1.57-1.68), lower serum sodium concentration (per 5-mEq/L [to convert to millimoles per liter, multiply by 1.0] increment; OR, 0.81; 95% CI, 0.78-0.83), lower systolic blood pressure (per 10-mm Hg increment; OR, 0.86; 95% CI, 0.85-0.88), higher serum urea nitrogen concentration (per 10-mg/dL to convert to millimoles per liter, multiply by 0.375] increment; OR, 1.20; 95% CI, 1.18-1.21), and absence of lipid-lowering drug therapy (use of drug OR, 0.69; 95% CI, 0.63-0.75). CONCLUSIONS: A small percentage of patients admitted to acute care hospitals with decompensated heart failure are referred to hospice at rates increasing with time. Hospitals that refer patients to hospice are more likely to be in compliance with heart failure performance measures. Further investigation is required to determine if the hospice option is appropriately selected and if it should be offered to a broader cohort of patients.     

Root canal treatment in a population-based adult sample: differences in patient factors and types of teeth treated between endodontists and general dentists

OBJECTIVE: The purpose of this study was to identify in a population-based study the differences between general dentists and endodontists with regard to types of teeth treated, fees, and patient characteristics. BASIC RESEARCH DESIGN: The "Florida Dental Care Study" was a prospective cohort study using a representative baseline sample of 873 dentate adults. In-person interviews and clinical examinations were conducted at baseline, 24 months, and 48 months, with 6-monthly telephone interviews between those times. Dental record information was abstracted afterward. RESULTS: A total of 100 root canals were performed in participants during the study period. While generalists performed the majority of endodontic procedures in all teeth, the percentage of molars treated by endodontists was significantly higher than the percentage of anterior teeth and bicuspids treated by endodontists. Data on fees were available in 85 of the cases. The trend was for endodontists fees to be higher, but the difference in fees was statistically significant only for molars. There were no statistically significant differences between generalist and specialist patients with regard to income, fear of pain, and frustration from previous dental care. However, a significantly higher percentage of patients treated by endodontists had dental insurance. CONCLUSIONS: Although the number of teeth ultimately treated in this representative sample of a dentate population was small, results do suggest that endodontists' fees were higher, they performed a higher percentage of molar root canals, and their patients were more likely to have dental insurance, as compared to general dentists who did root canals.     

Alternative and classical NF-kappa B signaling retain autoreactive B cells in the splenic marginal zone and result in lupus-like disease

Expression of B cell-activating factor (BAFF), a critical B cell survival factor, is elevated in autoimmune and lymphoproliferative disorders. Mice overproducing BAFF develop systemic lupus erythematosus (SLE)-like disease and exhibit B cell activation of classical and alternative NF-kappaB-signaling pathways. We used a genetic approach and found that both NF-kappaB-signaling pathways contributed to disease development but act through distinct mechanisms. Whereas BAFF enhanced long-term B cell survival primarily through the alternative, but not the classical, NF-kappaB pathway, it promoted immunoglobulin class switching and generation of pathogenic antibodies through the classical pathway. Activation of the alternative NF-kappaB pathway resulted in integrin upregulation, thereby retaining autoreactive B cells in the splenic marginal zone, a compartment that contributes to their survival. Thus, both classical and alternative NF-kappaB signaling are important for development of lupus-like disease associated with BAFF overproduction. The same mechanisms may be involved in the pathogenesis of human SLE.