Sociodemographic characteristics and diabetes predict invalid self-reported non-smoking in a population-based study of U.S. adults

Background  

Nearly all studies reporting smoking status collect self-reported data. The objective of this study was to assess sociodemographic characteristics and selected, common smoking-related diseases as predictors of invalid reporting of non-smoking. Valid self-reported smoking may be related to the degree to which smoking is a behavior that is not tolerated by the smoker's social group.     

Middle fossa acoustic tumor surgery: results in 106 cases

Although the middle cranial fossa approach has been used less frequently in recent years than in the past, it continues to be a useful technique for the removal of small acoustic tumors with possible hearing preservation. The approach provides complete exposure of the contents of the internal auditory canal, thus allowing positive facial nerve identification and facilitating total tumor removal. This paper reports the results of 106 middle fossa acoustic tumor removals over a 25-year period. Measurable postoperative hearing remained in 59% of cases. In 89% of cases, normal or near-normal postoperative facial nerve function was obtained. Total tumor removal was achieved in 98% of cases. Preoperative selection criteria are discussed, and postoperative complications are reported.     

Heterodimerization and functional interaction between EGF receptor family members: a new signaling paradigm with implications for breast cancer research

Summary The EGF receptor (EGFR) and HER2 are members of a growth factor receptor family. Overexpression of either protein in advanced breast cancer correlates with poor prognosis. EGF stimulates growth by binding to EGFR, activating the receptor's intracellular tyrosine kinase. The initial consequence is phosphorylation of specific tyrosine-containing sequences in the receptor's carboxyl terminus. These phosphotyrosines serve as high affinity recognition sites for proteins that, in turn, transmit the growth signal inside the cell. Mechanistic studies suggest that EGF binds to a single EGFR, triggering dimerization with another like receptor molecule. This dimerization is thought to initiate the tyrosine kinase activation.The EGF receptor family was recently expanded with the sequencing of HER3 and HER4. Each of the four family members was postulated to regulate a unique growth or differentiation signaling repertoire when activated by a receptor-specific ligand. However, new data from numerous laboratories suggest that EGFR family members may play a complex and ultimately more flexible role in signaling by forming heterodimers between family members, e.g. EGFR:HER2 or HER4:HER2. These heterodimers may form even when only one member of the pair binds its ligand.This review summarizes current work on heterodimerization and attempts to predict the consequences for downstream signaling. In brief, when compared to ligand-dependent receptor homodimers comprised of two proteins with the same internalization sequence and phosphorylated tyrosine residues, heterodimers are likely to: i) expand substrate selection and downstream signaling pathway activation; ii) promote interaction between sets of substrates in the mixed receptor complexes that would not ordinarily be physically juxtaposed; iii) alter the duration of receptor signaling by changing rates of receptor internalization, ligand loss, kinase inactivation, recycling, etc.; and iv) alter rates of receptor and substrate dephosphorylation. In addition to understanding interactions of heterodimers with the internalization machinery, identification of receptor-specific substrates and binding proteins for each EGFR family member will be necessary to explicate the role of heterodimers in growth and differentiation.     

Incidence of dental radiographic procedures during a 48-month population-based study of dentate adults

OBJECTIVES: The purpose of this population-based study was to quantify the incidence of radiographic procedures and the intervals between radiographic exposures. STUDY DESIGN: The Florida Dental Care Study was a prospective cohort study of a representative sample of dentate adults. In-person interviews and dental examinations were conducted at baseline, with subsequent interviews every 6 months during 48 months of follow-up. Dental record information was abstracted afterward. RESULTS: Thirteen percent of all dental procedures, and 42% of all diagnostic procedures, were radiographic. Annual person-level incidence of receipt of any radiograph was 48%. Incidence of specific types of radiographic procedures ranged from 5% to 30%. Among the 45% of the sample population who had had more than 1 bitewing procedure, 70% of the intervals between bitewing exposures were 1 year or longer. Receiving more than 1 full-mouth series or panoramic radiographic in any 24-month period was very rare. CONCLUSIONS: Annual incidence of radiographic procedures was substantially higher than the incidence reported in previous studies based on responses by dentists to hypothetical situations, but was stable during the 4 years of follow-up. On the basis only of intervals between exposures, and not of clinical status on the day of service, there was no substantial evidence of inappropriately frequent radiographic examinations.     

Management of amiodarone-induced thyrotoxicosis

Amiodarone is used increasingly in a number of cardiac conditions. Amiodarone is heavily iodinated and can cause thyroid dysfunction. The diagnosis of amiodarone-induced thyrotoxicosis remains difficult and more common causes of thyrotoxicosis need to be considered and excluded. Amiodarone has a significant side effect profile, which includes thyroid dysfunction. Amiodarone is an effective drug and its withdrawal may have significant impact on a patient's already fragile cardiac status. There are three different types of amiodarone-induced thyrotoxicosis (AIT) (I, II and mixed). Identification of the different subtypes of AIT allows a rational and appropriate management strategy to be chosen. Type I occurs in patients with underlying thyroid disease, whilst type II is thought to result from a destructive thyroiditis. Differentiation is based on clinical grounds together with investigations, which can include thyroid function test, radioiodine uptake scanning, measurement of interleukin-6 levels and colour flow Doppler sonography. Amiodarone should be discontinued in both types of AIT if the indication for its use is not a life-threatening cardiac condition. The management of type I centres around antithyroid drugs to control thyrotoxicosis and later consideration of more definitive treatment. Type II AIT responds to steroid therapy, although antithyroid drugs may be useful if symptoms are severe. Therapeutic options for refractory cases of AIT include surgery, radioiodine and plasmapheresis.     

Citalopram treatment of fluoxetine-intolerant depressed patients

BACKGROUND: We assessed the tolerability of and response to citalopram in depressed patients who had discontinued fluoxetine treatment due to adverse events. METHOD: Fifty-five outpatients with DSM-IV major depressive disorder and a confirmed history of intolerance to fluoxetine (mean final dose = 24.6 mg/day) were switched to citalopram (20 mg/day) after a 2- to 4-week single-blind placebo washout period. During a 6-week, open-label treatment protocol, citalopram could be titrated up to 40 mg/day. Safety and tolerability, including reemergence of symptoms that previously had been associated with fluoxetine, were assessed by recording all spontaneously reported or observed adverse events. Efficacy was evaluated using the Hamilton Rating Scale for Depression (HAM-D), the Clinical Global Impressions (CGI) scale, and several other measures. Response was defined as a CGI-Improvement score at endpoint of 1 or 2 (i.e., very much or much improved). RESULTS: Ninety-five percent of patients (N = 52) completed the citalopram trial. The only adverse events reported by more than 5 patients (>or= 10%) were pharyngitis (15%) and constipation (11%), and none of the 3 early terminations were attributed to adverse events. The rate of recurrence of the fluoxetine-associated adverse events was low, with headache (3 [27%] of 11 cases), nausea (2 [22%] of 9 cases), and decreased libido (5 [18%] of 28 cases) being the most common. Significant improvement from baseline HAM-D (p <.001) was observed by the first week of citalopram therapy and continued until study end. The intent-to-treat CGI response rate was 65% (36 of 55 patients) at study endpoint; 69% (36 of 52 patients) of the completers responded. CONCLUSION: These data suggest that fluoxetine-intolerant patients can be treated effectively with citalopram.     

Surgical management of Novacor drive-line exit site infections

Implantable left ventricular assist device (LVAD) drive-line exit site infection, an expected consequence of currently available device use, continues to be a significant limiting factor in long-term support. We theorize that the mechanism behind the establishment of the most chronic exit site infections involves a shearing torsion injury that disrupts the tissue adherence interface with the drive-line. The resulting neo-epithelialized drainage tract prevents permanent clearance of the infection with antibiotics alone. The proposed treatment strategy of established infections involves aggressive surgical excision of the involved exit site.     

Effects of Fractions from Biodegraded Alaska North Slope Crude Oil on Embryonic Inland Silversides, <Emphasis Type="Italic">Menidia beryllina</Emphasis>

Embryonic inland silversides, Meinida beryllina, were exposed to neutral, water-soluble fractions (WSFs) resulting from microbial degradation of artificially weathered Alaska North Slope (ANS) crude oil. Three individual microbes obtained from Prince William Sound, Alaska, and designated Phe#6 (enriched on phenanthrene), Hexaco#2 (enriched on the straight-chain alkane, hexacosane), and EI2V (grown by enrichment on Bushnell-Haas medium containing 0.2% pristane, a branched alkane) were used to individually biodegrade weathered ANS crude oil for 14 days in darkness in 20-L glass carboys containing nutrient enriched, sterilized 20‰ salinity sea water at 20 ± 1°C. Neutral WSFs resulting from biodegradation of ANS (lot 521) by each microbe were recovered and weighted. Neutral WSFs recovered were: 1.76 mg/L for Phe#6, 1.85 mg/L for Hexaco#2, and 13.02 mg/L for the EI2V microbe. Embryo toxicity and teratogenicity tests revealed that exposure of embryos to the WSFs from the EI2V incubation (with a total recovered neutral fraction approximately seven times greater than the Phe#6 and Hexaco#2 incubations) resulted in the most severe responses in craniofacial, cardiovascular, and skeletal organ systems. The total neutral WSFs recovered from the EI2V biodegradation of weathered ANS 521 were subfractionated into saturated (eluted with hexane), aromatic (eluted with CH₂Cl₂), polar (eluted with ethyl ether), and recombined (saturated + aromatic + polar) fractions. Developing fish embryos were then exposed to each subfraction and the recombined subfractions. The polar subfraction and recombined subfractions proved to be the most embryo toxic and teratogenic. They resulted in statistically significant (p ≤ 0.05) responses (compared to controls) for craniofacial, cardiovascular, skeletal, and total severity effects in one or both tests with these subfractions. Received: 14 June 2001/Accepted: 26 August 2001     

Recruitment and Retention of Physicians for Primary Care Research

The primary objective of this report is to examine factors associated with recruitment of physicians in community-based primary care research. Reported results are based on an observational study of physician recruitment efforts undertaken in a randomized controlled trial designed to improve primary care physicians' cancer screening and counseling activities. The Partners for Prevention project was a state-wide randomized controlled trial of primary care physicians selected from the state of Colorado. Two-hundred and ten eligible internal medicine and family medicine practices in both rural and urban community settings of the state of Colorado were selected into this study and a sentinel physician was chosen to represent each practice. Only 6% (13/210) of recruited practices initially declined to participate in the study, but the total refusal rate had reached 30% (59/210) by the time the intervention was implemented five months later. Study participants (n = 136) were younger (mean age 45.7 vs. 50.0, p = 0.008) and more often located in a rural area (46% vs. 31%, p = 0.04) than decliners (n = 59), but there was no association with gender of the physician (87% for females vs. 95% for males, p = 0.13). Participants were more often family practice physicians by training rather than internists (75% vs. 56%, p = 0.008), whereas there was no difference in participation rates by practice type (solo versus group, 60% vs. 64%, p = 0.52). Differences in demographic, geographic, and training characteristics between trial participants and decliners suggest the potential for better targeting of recruitment efforts. Viable strategies for recruiting community-based primary care practices to research studies are proposed.