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Training on the clock: family medicine residency directors' responses to resident duty hours reform.

PURPOSE: The Accreditation Council for Graduate Medical Education's 2003 restrictions on resident duty hours (RDH) raised concerns among educators about potential negative impacts on residents' training. In the early wake of these restrictions, little is known about how RDH reform impacts training in primary care. The authors surveyed family medicine (FM) residency program directors (PDs) for their perceptions of the impact of RDH regulations on training in primary care. METHOD: All PDs of 472 FM residency programs were asked via list-serve to complete an anonymous Internet-based survey in the fall of 2004. The survey solicited PDs' opinions about changes in staff and in residents' training experiences with respect to implementation of RDH regulations. Descriptive and qualitative analyses were conducted. RESULTS: There were 369 partial and 328 complete responses, for a response rate of 69% (328/472). Effects of the RDH regulations are varied. Fifty percent of FMPDs report increased patient-care duties for attendings, whereas 42% report no increase. Nearly 80% of programs hired no additional staff. Sixty percent of programs eliminated postcall clinics, and nearly 40% implemented a night-float system. Administrative hassles and losses of professionalism, educational opportunity, and continuity of care were common concerns, but a sizeable minority feel that residents will be better off under the new regulations. CONCLUSIONS: Many FMPDs cited increased faculty burden and the risk of lower-quality educational experiences for their trainees. Innovations for increasing the effectiveness of teaching may ultimately compensate for lost educational time. If not, alternatives such as extending the length of residency must be considered.

Accreditation↗

Biodegradation of polydioxanone in bone tissue: effect on the epiphyseal plate in immature rabbits.

Implants of polydioxanone (PDS), 1.3 mm in diameter, were operatively fixed in the juxta-epiphyseal area of the right proximal tibial metaphysis in six rabbits and were driven into a drill hole of equal bore through the right proximal tibial epiphyseal plate in ten rabbits. The PDS implants had biodegraded almost completely in cortical bone at 16 weeks without any significant sign of inflammation or foreign body reaction. The PDS implants did not cause any growth disturbance. Histologic studies, however, showed that seven of 10 rabbits demonstrated significant osseous bridge formation across the epiphyseal plate.

Animals↗

Biodegradable fixation of physeal fractures in goat distal femur.

We compared the effectiveness of absorbable polylactic acid (PLA) screws and polydioxanone (PDS) pins with that of ASIF cannulated screws in stabilizing Salter-Harris IV fractures in goat distal femur. Eighteen juvenile goats were randomly divided into control (cannulated screw), PLA screw, and PDS pin groups. A Salter-Harris IV medial femoral condyle fracture was created and stabilized, and the goats were sacrificed 8 weeks postoperatively. Articular cartilage displacement < 1 mm was considered anatomic. All PLA screws were anatomic as compared with 83% (five of six) of the controls and 17% (one of six) of the pins. Absorbable PLA screws stabilized Salter-Harris IV fractures as well as cannulated screws and better than PDS pins.

Animals↗

Functional analysis of the early steps of carotenoid biosynthesis in tobacco.

Carotenoids contribute to energy transduction in the light harvesting complexes and serve in protection from excess light fluence. Because of the importance of carotenoids, the genes encoding enzymes of carotenoid biosynthesis in higher plants are potential targets for herbicides. To obtain further insight into tobacco carotenoid biosynthesis and to investigate and prioritize potential herbicide targets in the pathway, the effects of changed phytoene synthase (PSY) and phytoene desaturase (PDS) gene expression were studied in transgenic tobacco (Nicotiana tabacum Petit Havana SR1) plants. Genes for both enzymes were cloned from tobacco, and surprisingly two functional PSY genes were found. Transgenic tobacco plants constitutively expressing these genes in both sense and antisense orientations were examined regarding phenotype, carotenoid content and transcript levels of carotene biosynthesis genes. Overexpression of either psy gene resulted in severe phenotypic effects including dwarfism, altered leaf morphology, and pigmentation. A correlation among phenotype, transcript level, and metabolic profile was demonstrated by comparison of hemizygous and homozygous plants from the same transformation event. Antisense expression of PSY and PDS also caused lethal phenotypes. Transcript levels of other carotene biosynthesis genes remained unaltered in the transgenic mutant. Phytoene accumulated in plants expressing antisense RNA to pds. However, elevated levels of phytoene were detected suggesting an increase in metabolic flux into this pathway.

Alkyl and Aryl Transferases↗

New adaptive partial distortion search using clustered pixel matching error characteristic.

In order to reduce the computation load, many conventional fast block-matching algorithms have been developed to reduce the set of possible searching points in the search window. All of these algorithms produce some quality degradation of a predicted image. Alternatively, another kind of fast block-matching algorithms which do not introduce any prediction error as compared with the full-search algorithm is to reduce the number of necessary matching evaluations for every searching point in the search window. The partial distortion search (PDS) is a well-known technique of the second kind of algorithms. In the literature, many researches tried to improve both lossy and lossless block-matching algorithms by making use of an assumption that pixels with larger gradient magnitudes have larger matching errors on average. Based on a simple analysis, it is found that, on average, pixel matching errors with similar magnitudes tend to appear in clusters for natural video sequences. By using this clustering characteristic, we propose an adaptive PDS algorithm which significantly improves the computation efficiency of the original PDS. This approach is much better than other algorithms which make use of the pixel gradients. Furthermore, the proposed algorithm is most suitable for motion estimation of both opaque and boundary macroblocks of an arbitrary-shaped object in MPEG-4 coding.

Algorithms↗

Epidermal proliferation but not quantity of DNA photodamage is correlated with UV-induced mouse skin carcinogenesis.

The hairless SKH-1 mouse strain has a higher skin tumor incidence, shorter tumor latency, and higher tumor yield in response to ultraviolet (UV) irradiation than the SENCAR strain. In this study we assessed the differences in UV susceptibility of both strains by measuring DNA photodamage and epidermal proliferation after one UV treatment and after 1, 3, 6, and 9 wk of chronic UV irradiation. Induction rates for cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4) PDs] were significantly greater in the SKH-1 strain than the SENCAR strain, but no strain differences in repair kinetics were detected for CPDs or (6-4) PDs. With chronic UV exposure we observed the following: (i) there was an equal amount of DNA photodamage in both strains; (ii) the number of (6-4) PDs was significantly greater than the CPDs after 6 wk; (iii) there were a significantly greater number of epidermal cells (1.5-fold increase) in the SKH-1 strain; (iv) the number of cycling cells, as measured by 5-bromo-2'-deoxyuridine (BrdU), were located both basally and suprabasally and were significantly greater in the SKH-1 strain; and (v) the number of cells immunoreactive to p53 was equivalent in both strains, but immunoreactive cells were located suprabasally in the SKH-1 strain after 9 wk of UV. These results show that the etiologic role of UV in tumorigenesis is dependent on events other than the amount of DNA photodamage in mouse epidermis.

Animals↗

Phenotype modulation in primary cultures of arterial smooth muscle cells. On the role of platelet-derived growth factor.

Smooth muscle cells were isolated from adult rat aorta by collagenase digestion, grown in primary culture in the presence of 10% whole blood serum (WBS), and studied by quantitative electron microscopy and thymidine autoradiography in order to correlate cellular fine structure and proliferation. On day 2-4, the cells passed through a structural transition from contractile to synthetic state. In the former they were characterized by predominance of cytoplasmic microfilament bundles and in the latter by an extensive rough endoplasmic reticulum (RER) and a large Golgi complex. The disappearance of the microfilament bundles was accompanied by a transient increase in lysosomal volume density but no signs of bulk autophagy. This suggests that microfilaments were disassembled into subunit proteins and that lysosomes were engaged in adjusting the pool of free subunits into a new equilibrium. RER cisternae grew out from the nuclear envelope and successively spread throughout the cytoplasm. Stacks of Golgi cisternae were organized in a circumscribed juxtanuclear region. The structural modulation occurred also in medium containing 10% plasma-derived serum (PDS). Its onset was delayed by addition of antibodies (50 micrograms/ml) against platelet-derived growth factor (PDGF) to 10% WBS-medium and speeded up by addition of purified PDGF (25 ng/ml) to 10% PDS-medium. Otherwise, the kinetics of the structural modulation was the same in all experimental groups. The observations could not be explained by overgrowth of contaminating fibroblasts since (1) successive steps in the process were clearly evident, (2) the cells surrounded themselves by an incomplete basement membrane, a characteristic feature of smooth muscle, and (3) mitomycin C blocked cell growth but not conversion from contractile to synthetic state. After 3-4 days of culture in 10% WBS-medium, active DNA synthesis and cellular proliferation were initiated as determined autoradiographically and by cell counting. Electron microscopic autoradiography showed that all cells were morphologically in the synthetic state at the time of entrance into S-phase. Initially, the cells grew at a lower rate in the presence of PDGF antibodies but after 5-6 days of culture attained a rate similar to that in the controls. No distinct proliferation was obtained in 10% PDS-medium unless purified PDGF (10 ng/ml) was added during the first days of culture. The results suggest that the structural modulation of the smooth muscle is an absolute but not sufficient prerequisite for cellular proliferation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Imaging properties of polydioxanone and titanium ligating clips following para-aortic lymphadenectomy for testicular cancer.

Stainless steel ligating clips produce serious artefacts on CT scans. Polydioxanone (PDS) and titanium ligating clips were used in 15 patients during para-aortic lymphadenectomy for residual metastatic testicular teratoma following chemotherapy, and follow-up CT images were compared with those following the use of stainless steel ligating clips. PDS ligating clips did not produce any artefacts and were progressively absorbed. Titanium ligating clips produced artefacts similar to but less intense than those of stainless steel. PDS ligating clips should be used when follow-up CT scanning is important.

Constriction↗

The long-term outcome of the endoscopic subureteric implantation of polydimethylsiloxane for treating vesico-ureteric reflux in children: a retrospective analysis of the first 195 consecutive patients in two European centres.

OBJECTIVE: To determine the long-term efficacy of endoscopically implanting polydimethylsiloxane (PDS, Macroplastique, Uroplasty BV, Geleen, the Netherlands) for treating vesico-ureteric reflux (VUR) in children. PATIENTS AND METHODS: We retrospectively reviewed the records of 195 children treated with PDS over the past 10 years in two European centres (Netherlands and UK) and conducted follow-up investigations where deemed necessary. In the Dutch centre patients were treated according to a prospective approved study protocol. RESULTS: Of the 195 treated children, 155 had a successful outcome; in all, 311 refluxing renal units were treated, with an overall success rate of 82.3% in a mixed group of patients with unilateral or bilateral VUR and duplex systems. CONCLUSION: The long-term data from these two independent centres confirms the viability of PDS and the technique for treating VUR in children. We conclude that the material is safe and effective and can be used in VUR grades II-V. Treating patients with grade I VUR is recommended in those cases where there is no spontaneous resolution and 'breakthrough' infections.

Adolescent↗

Decreased approach motivation in depression.

The present study examined relations between choice preference and reaction time to emotionally valenced words, dysphoric symptoms (BDI), and dysfunctional attitudes (DAS) in clinically depressed (CD; n= 61), previously depressed (PD; n= 42), and never depressed controls (ND; n= 46). The results showed: (1) NDs and PDs exhibited a choice preference for the relatively more positive words and differed significantly from CDs; (2) PDs and CDs exhibited longer reaction time and differed significantly from NDs; and (3) BDI and DAS were positively associated with reaction time to positively valenced words, whereas no associations were found for reaction time to negatively valenced words. The increased reaction time, in PDs and CDs, is discussed as a possible vulnerability factor to depression, which may be related to decreased approach motivation.

Adolescent↗

Excessive daytime somnolence in Japanese patients with Parkinson's disease.

To investigate the prevalence and severity of excessive daytime somnolence (EDS) in Japanese patients with Parkinson's disease (PD) and to examine the main cause of EDS. Fifty-three Japanese patients with PD (PDs: 32 females and 21 males) and 17 controls (10 females and seven males) were evaluated using the Epworth Sleepiness Scale (ESS). The severity of the disease was evaluated by Unified Parkinson's disease Rating Scale (UPDRS), and information about quality and quantity of medications was collected. The correlations amongst EDS and age, severity of PD, duration of illness and medications were analyzed. The mean ESS score was significantly higher in advanced PDs than in controls, and correlated with the UPDRS score (r(s) = 0.743, P < 0.0001). Age, duration of illness and the dose of levodopa weakly correlated with ESS score. The intake of dopamine agonists did not affect the severity of EDS. The mean ESS score in PDs was lower than that reported in PD in European and American studies. EDS in Japanese patients with PD was milder compared with Caucasian patients, which might be due to the lower doses of the medications used in Japan. The results suggest that EDS in PD is mainly because of neuropathological changes of the disease itself.

Aged↗

Assessment of penetrance and expressivity of RNAi-mediated silencing of the Arabidopsis phytoene desaturase gene.

RNA interference (RNAi) is of great value in plant functional genomics. However, the absence of RNAi phenotypes and the lack of uniform level of RNAi silencing has complicated gene identification. Here, the penetrance and expressivity of RNAi-mediated silencing of the phytoene desaturase (PDS) gene in Arabidopsis thaliana were examined quantitatively to provide a reference for the likely severity and distribution of silencing effects. Arabidopsis plants were transformed with an RNAi construct targeting PDS. Transgenic plants were examined for frequency of RNAi-mediated silencing and various silencing phenotypes. mRNA depletion level and RNAi expressivity were assayed by relative reverse transcription polymerase chain reaction (RT-PCR). High penetrance and variable expressivity of RNAi were demonstrated. An inverse correlation between PDS mRNA level and RNAi phenotype was seen. No direct relationship between copy number for the RNAi-generating transgene and phenotype was evident. Decreased RNAi penetrance in T2 plants was observed. It is suggested that variability in RNAi expressivity and postmeiotic decrease in RNAi penetrance constitute barriers for high throughput plant gene characterization.

Arabidopsis↗

Lateral hemifield flickering pattern stimulation in a patient with pattern-sensitive epilepsy.

Provocative effects of paroxysmal discharges (PDs) by lateral hemifield pattern stimuli were studied in a 24-year-old female patient with pattern-sensitive epilepsy. Provocation of focal posterior PDs in the contralateral hemisphere became more evident by adding 15/s flicker to the lateral hemifield pattern (hemifield flickering pattern) stimuli than by stimulus with the lateral hemifield grate pattern or with the lateral hemifield dot pattern alone. Such a finding was also observed when lateral hemifield flickering pattern stimuli were given to each eye. In this patient, left hemifield flickering pattern stimuli were slightly more effective than right hemifield stimuli in provoking the corresponding focal posterior PDs. It is suggested that lateral hemifield flickering pattern stimuli might be useful for a precise EEG examination of the posterior regions of the brain in patients with pattern-sensitive epilepsy and allied conditions.

Adult↗

Effects of valproate in a model nervous system (buccal ganglia of Helix pomatia): II. Epileptogenic actions.

High concentrations of valproate (VPA; greater than 20 mM) depolarized identified neuronal individuals in the buccal ganglia of Helix pomatia and transiently induced paroxysmal depolarization shifts (PDS). Threshold concentration of VPA for the induction of PDS was decreased (a) by increased seizure susceptibility, (b) by increased concentrations of derivatives of VPA, and (c) by increased H+ concentrations. Intrasomatic injection of VPA did not induce PDS. The epileptogenic action of VPA is believed to be exerted from the extracellular side of the cell membrane.

Animals↗

Suicidal behavior in alcohol-dependent subjects: the role of personality disorders.

BACKGROUND: Comobidity of personality disorders (PDs) and alcohol dependence are considered to increase the risk for suicidal behavior. The aim of this study is to assess the influence of Diagnostic and Statistical Manual of Mental Disorder-fourth edition (DSM-IV) personality characteristics and comorbid axis I disorders on suicidal behavior in alcohol-dependent inpatients. METHODS: Characteristics of alcohol dependence and suicidal behavior were obtained using the Semi-Structured Assessment on Genetics in Alcoholism (SSAGA). Personality disorder characteristics were assessed using the Structured Clinical Interview for DSM-IV Axis II Disorders. RESULTS: Three-hundred seventy-six treatment-seeking alcohol-dependent subjects, of whom 55% were diagnosed to have a PD and approximately 25% had a history of at least 1 suicide attempt, were enrolled into the study. Subjects with PDs in all clusters reported a higher rate of suicide attempt history, depression episodes, and depression during the most serious attempt. As indicated by univariate and multivarate analysis, this pattern of suicide attempt characteristics was most pronounced in borderline disordered subjects and alcoholic individuals who live alone. CONCLUSION: Subjects with alcohol dependence who have various comorbid PDs and depression deserve special attention in psychiatric care to prevent suicide. Psychotherapeutic strategies may have to be adapted to treat this high-risk population.

Adult↗

Importance of electrode conductive surface area and edge effects on ventricular defibrillation efficacy.

INTRODUCTION: The role of edge effects and electrode surface area of the right ventricular (RV) transvenous lead (TVL) on defibrillation efficacy is unknown. METHODS AND RESULTS: Defibrillation threshold (DFT) testing was conducted randomly in 12 dogs using ring electrode leads in an RV/SVC (superior vena cava) or RV/SVC/patch system. The leads (RV-4, RV-8t, RV-8, RV-15) had electrode surface areas of 20%, 20%, 40%, and 70%, respectively. A computer model predicted the magnitude of electrode surface current (RV-8t > RV-4 > RV-8 > RV-15) and the potential distribution (PD) at four sites: electrode surface (site a) and at 2 mm (b), 4 mm (c), and 8 mm (d) away from the surface. Despite different near-field PDs (sites a, b, c), PDs were nearly identical at site d. Resistance decreased as the surface area increased. DFT energy for the RV-15 lead was lower than the RV-4 and RV-8t. There was no difference between energy requirements for the RV-15 and RV-8 leads. No difference was found in DFT current for each lead. Comparison of the RV-8t and RV-4 leads showed no difference in DFT energy despite a lower resistance and a greater number of edges. CONCLUSIONS: Increasing the RV TVL surface area lowered the resistance. However, surface area coverages > or = 40% did not lower DFT energy. No significant change in DFT current occurred despite different predicted near-field current densities. PDs were nearly identical 8 mm from the electrode surface. Thus, the far-field current density appears to play a more important role in determining defibrillation success.

Animals↗

Graduate medical education downsizing: perceived effects of participating in the HCFA demonstration project in New York State.

OBJECTIVE: Financial support for graduate medical education (GME) is shrinking nationally as Medicare cuts GME funds. Thirty-nine hospitals in New York State (NYS) voluntarily participated in a Health Care Financing Administration demonstration project (HCFADP)-the goal of which was to reduce total residency training positions by 4-5%/year over a five-year period, while increasing primary care positions. The objective of this study was to determine the effect of downsizing on emergency department (ED) staffing and emergency medicine (EM) residency training. METHODS: Structured interviews and surveys of NYS program directors (PDs) were conducted in October-December 1999. Simple frequencies are reported. RESULTS: One hundred percent of 17 PDs completed the interviews and seven of 12 participants in the HCFADP returned surveys. Twelve of 17 programs participated in HCFADP and two programs downsized outside HCFADP. Seven of 12 participants lost EM positions. Six of 12 programs were forced to exclude outside residents from rotating in their ED, leading to a need for one participating program and one non-participating program to find alternative sites for trauma. Five of 12 institutions provided resident staffing data, reporting a reduction in ED resident coverage in year 1 of the project of 9-40%. Programs compensated by increasing the number of shifts worked (4/12), increasing shift length (1/12), decreasing pediatric ED shifts (1/12), decreasing elective or research time (2/12), and decreasing off-service rotations (4/12). Six departments hired physician assistants or nurse practitioners, two hired faculty, and two hired resident moonlighters. Six of 12 programs withdrew from HCFADP and returned to previous resident numbers. Eight of 12 PDs thought that they had decreased time for clinical teaching. CONCLUSIONS: A 4-5% reduction in residency positions was associated with a marked reduction in ED resident staffing and EM residency curriculum changes.

Centers for Medicare and Medicaid Services, U.S.↗

Achalasia: should we or should we not follow the bag?

This article concerns the long-term therapeutic effect of pneumatic dilations (PDs) in achalasia. Specifically, it is a retrospective study that follows a large cohort of achalasia patients treated with PD. Efficacy and need for repeat PDs were determined utilizing a score obtained from measuring symptoms after PD. After PDs that resulted in symptomatic improvement, patients were followed at 6-month intervals to determine the need for repeat PD. The major point of this article is that exacerbations of symptoms may occur in 35% of patients undergoing PD; however, follow-up at specific intervals using a symptom score to determine the need for repeat PD resulted in excellent long-term success. This article emphasizes the need for continued follow-up of achalasia patients following initial successful therapy.

Catheterization↗