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Has the growth and development of subspecialization in pediatric urology affected scholarly activity?

PURPOSE: How has academic productivity changed in a decade in the American Academy of Pediatrics Section on Urology? Do academic pursuits slow as section members become older? What is the average number of publications yearly by section members? What percent of research is funded in pediatric urology? Has change occurred with multiple authorships? MATERIALS AND METHODS: American Academy of Pediatrics Urology Section active memberships for 1993 and 2003 were obtained. A PubMed study was performed by reviewing all manuscripts published by American Academy of Pediatrics Section on Urology active members for 1991 to 1993 and 2001 to 2003. The data recorded were author, year, PubMed identification number, the number of authors, financial support and journal. Parametric and nonparametric statistics were used for analysis. RESULTS: In the 1991 to 1993 era there were 245 active members, of whom 145 published a total of 972 manuscripts. There were 604 clinical authorships, 161 basic science articles, 42 reviews and 186 case reports, of which 154 manuscripts received funding. In the 2001 to 2003 era there were 252 members, of whom 177 published a total of 1,152 manuscripts. There were 773 clinical authorships, 140 basic science articles, 107 reviews and 124 case reports, of which 151 manuscripts receiving funding. For members in the 2 periods the mean number of articles decreased by 1.0 from 1 decade to the next (p = 0.002). CONCLUSIONS: Scholarly pursuit of pediatric urology as a subspecialty has remained remarkably steady, averaging about 2 authorships per author yearly in the recent decade. The percent of authorships with funding in pediatric urology has decreased. The number of funded authorships has remained steady. A higher percent of American Academy of Pediatrics members have published manuscripts in the last decade. More manuscripts were published during the last decade study period than during the prior decade. The mix of manuscript types has changed with more reviews, and fewer case reports and basic science authorships in the most recent decade. New members are more likely to publish with a low unpublished percent.

Bibliometrics↗

Plasma amine oxidase: a postulated cardiovascular risk factor in nondiabetic obese patients.

Increased activity of semicarbazide-sensitive plasma amine oxidase (SSAO), an enzyme converting various amines, has been implicated in the generation of endothelial damage through formation of cytotoxic reaction products. We investigated if SSAO activity is elevated in morbidly obese patients, which might contribute to the increased cardiovascular risk associated with obesity. SSAO activity was determined in 74 nondiabetic, obese patients (median body mass index [BMI]: 42.9 kg/m(2)) and in 32 healthy, non-obese controls (median BMI: 23.3 kg/m(2)) using a radiometric assay based on the conversion of [(14)C]benzylamine. SSAO and parameters of glucose and lipid metabolism were compared for subgroups of obese patients with normal (n = 49) and impaired (n = 25) glucose tolerance using nonparametric statistical tests. Median SSAO activity was 434 microU/mL in obese patients, which was significantly higher than in healthy, non-obese controls (median SSAO activity: 361 microU/mL). Median SSAO activity in patients with normal and impaired glucose tolerance was 423 and 464 microU/mL, respectively. SSAO activity was not correlated with any other clinical or laboratory parameters characteristic of the metabolic alterations associated with obesity. Elevated SSAO activity is found in nondiabetic, morbidly obese patients and might be an interesting independent risk factor for obesity-related cardiovascular morbidity. Long-term follow-up of SSAO and its possible role in pathogenic events is warranted since intervention with specific SSAO inhibitors is available.

Adult↗

What to expect from a residency program: answers from a directory of residency programs in obstetrics and gynecology.

OBJECTIVE: To answer questions about obstetric-gynecologic resident salary, night call, vacation, outside employment, gender mix, and training experiences using data from a national directory of residency programs in obstetrics and gynecology. METHODS: The 259 US civilian residency programs were analyzed, using information from the 1996 directory database. We compared programs by size (four or fewer residents per year versus more than four residents per year) and geographic region for each of the questions. We used parametric and nonparametric statistical tests to determine statistical significance. RESULTS: First-year residents earn an average of $31,414 annually and receive a 5% increase each year, although salary varies significantly by region. Residents are on call an average of every 3rd night (twice a week) in the 1st year and every 4th or 5th night in the chief year. Residents in small programs take more night call than those in large programs. A separate night call rotation was more common in large programs. Vacation time varied by year of training and region. Male-to-female ratios in training differed significantly by year in training, program size, and region. The median number of training experiences was identified in each of the categories required by the Residency Review Committee in obstetrics and gynecology. Training experiences varied significantly by program size in three of the 15 categories. CONCLUSION: Program size and geographic region should be considered when comparing programs with regard to pay, work, time off, outside employment, gender mix, and training experiences. Program advisors and potential applicants are encouraged to use this information in comparing programs.

Female↗

Adenoid cystic carcinoma of the lacrimal gland: the clinical significance of a basaloid histologic pattern.

The authors reviewed 74 adenoid cystic carcinomas of the lacrimal gland, 54 of which had sufficient follow-up data for analysis of survival. Patients with a basaloid pattern in their tumor had a five-year survival rate of 21 per cent and a median survival of three years, whereas patients whose tumor contained no trace of a basaloid component had a five-year survival rate of 71 per cent and a median survival rate of eight years. Nonparametric statistical analysis revealed that this difference in survival was significant at the 0.0005 level. The authors propose that, in the future, pathologists label all adenoid cystic carcinomas as either "basaloid" or "nonbasaloid" and code each case accordingly.

Adult↗

Conservative treatment of female urinary incontinence with functional magnetic stimulation.

OBJECTIVES: To determine the efficacy and safety of functional magnetic stimulation (FMS) produced by the Pulsegen device compared with placebo in the treatment of women with urinary incontinence. METHODS: Fifty-five women with urinary incontinence were randomly assigned to the active FMS group (30 patients) or the placebo group (22 patients). Each patient in the active group received a Pulsegen device, which produced a pulsating magnetic field of B = 10 microT intensity and a frequency of 10 Hz. Patients were asked to wear the Pulsegen device day and night for 2 months. Clinical and urodynamic data were collected before and after FMS and analyzed using nonparametric statistics. RESULTS: Compared with the placebo, the number of pads used was significantly lower (P = 0.0031) after FMS, as was the pad weight (P = 0.014). In patients from the active group, a significant improvement in the power of the pelvic floor muscle contractions (P = 0.0071), as well as in the duration of the pelvic floor muscle contractions (P = 0.038), was observed. After FMS, a 56.3% improvement in urinary incontinence symptoms was reported by patients in the active group, a significantly greater difference (P = 0.00012) compared with the reported 26.3% improvement in symptoms in the placebo group. CONCLUSIONS: We believe that FMS represents a new method in the conservative treatment of urinary incontinence. Magnetic stimulation with the Pulsegen device is efficient and safe. It can be used at home and, because of its small size, wearing the device is not annoying for patients.

Adult↗

Canal debridement: effectiveness of sodium hypochlorite and calcium hydroxide as medicaments.

The action of chemicals such as calcium hydroxide (Ca(OH)2) and sodium hypochlorite (NaOCl) that are used as tissue solvents may be enhanced by prolonged contact. The objective of this study was to determine if sealing Ca(OH)2 and NaOCl into the canal space would improve debridement of both the main canal and areas inaccessible to files. Mesial root canals of 75 freshly extracted mandibular molars were step-back hand-instrumented. Another six molars were controls. Either Ca(OH)2, NaOCl, or no medication was sealed in the canals for 1 or 7 days. Canals were finally irrigated with H2O and prepared for histological evaluation. The cleanliness of main canals and inaccessible areas (isthmi and fins) at the apical, middle, and coronal thirds was examined, scored, and compared by nonparametric statistical analysis. Results showed no significant differences among different groups in either the 1-day or 7-day time intervals in either the main canal or inaccessible areas. Instrumentation combined with NaOCl irrigation alone accounted for the removal of tissue in the main canal. In conclusion, in this system, prolonged contact with Ca(OH)2 and NaOCl was similarly ineffective; neither contributed significantly to canal debridement.

Analysis of Variance↗

Electrochemical characterization of cast titanium alloys.

A reaction layer forms on cast titanium alloy surfaces due to the reaction of the molten metal with the investment. This surface layer may affect the corrosion of the alloy in the oral environment. The objective of this study was to characterize the in vitro corrosion behavior of cast titanium alloys. ASTM Grade 2 CP titanium, Ti-6Al-4V, Ti-6Al-7Nb and Ti-13Nb-13Zr alloys were cast into a MgO-based investment. Experiments were performed on castings (N=4) with three surface conditions: (A) as-cast surface after sandblasting, (B) polished surface after removal of the reaction layer, and (C) sandblasted surface after removal of the reaction layer. Open-circuit potential (OCP) measurement, linear polarization, and potentiodynamic cathodic polarization were performed in aerated (air+10% CO(2)) modified Tani-Zucchi synthetic saliva at 37 degrees C. Potentiodynamic anodic polarization was subsequently conducted in the same medium deaerated with N(2)+10% CO(2) gas 2 h before and during the experiment. Polarization resistance (R(P)) and corrosion rate (I(CORR)) were calculated. Numerical results were subjected to nonparametric statistical analysis at alpha=0.05. The OCP stabilized for all the specimens after 6 x 10(4)s. Apparent differences in anodic polarization were observed among the different surfaces for all the metals. A passivation region followed by breakdown and repassivation were seen on specimens with surfaces A and C. An extensive passive region was observed on all the metals with surface B. The Kruskal-Wallis test showed no significant differences in OCP, R(p), I(CORR) or break down potential for each of the three surfaces among all the metals. The Mann-Whitney test showed significantly lower R(P) and higher I(CORR) values for surface C compared to the other surfaces. Results indicate that the surface condition has more effect on corrosion of these alloys than the surface reaction layer. Within the oxidation potential range of the oral cavity, all the metal/surface combinations examined showed excellent corrosion resistance.

Alloys↗

Corrosion behavior of cast titanium with reduced surface reaction layer made by a face-coating method.

This study characterized the corrosion behavior of cast CP titanium made with a face-coating method. Wax patterns were coated with oxide slurry of Y(2)O(3) or ZrO(2) before investing with a MgO-based investment. Three surface preparations were tested: ground, sandblasted, and as-cast. Uncoated castings served as controls. Sixteen-hour open circuit potential (OCP) measurement, linear polarization and potentiodynamic cathodic polarization were performed in an aerated modified Tani-Zucchi synthetic saliva at 37 degrees C. Anodic polarization was conducted in the same deaerated medium. Polarization resistance (R(p)) and Tafel slopes were determined. Corrosion current density was calculated for each specimen. Results (n=4) were subjected to nonparametric statistical analysis (alpha=0.05). Cross sections of cast specimens were examined by optical microscopy. Energy dispersive spectroscopy (EDS) spot analysis was performed at various depths below the surface. The OCP stabilized within several hours for all the specimens. Apparent differences in anodic polarization behavior were observed among the different surfaces. A distinctive wide passive region followed by breakdown was seen on specimens with ground and sandblasted surfaces. There were no significant differences in the corrosion resistance among the control and the two face-coating groups for each group. The Mann-Whitney test showed significantly lower OCP and higher R(p) values for ground surfaces. The surface condition significantly affected the corrosion behavior more than the face coating methods. In most cases, specimens with as-cast surfaces exhibited the least corrosion resistance during the potentiodynamic anodic polarization.

Coated Materials, Biocompatible↗

Laser in situ keratomileusis-induced (presumed) neurotrophic epitheliopathy.

OBJECTIVE: To evaluate tear production, corneal topography, accuracy of refractive correction, and best spectacle-corrected visual acuity in eyes that had moderate to severe rose bengal staining develop on the flap compared with eyes with little or no staining on the flap, the first few months after laser in situ keratomileusis (LASIK). None of the eyes in this study had significant preoperative dry eye disease. DESIGN: Retrospective case control study. PARTICIPANTS: Individual eyes of 19 consecutive patients with moderate to severe punctate epithelial erosions and rose bengal staining on the flap 1 to 3 months after LASIK were compared with eyes of 19 concurrent patients who did not have punctate epithelial erosions or more than trace staining on the flap develop. METHODS: Nonparametric statistical analyses were used to compare tear secretion, corneal topographic irregularity, spherical equivalent, and visual acuity 3 and 6 months after surgery. Some eyes in both groups also had analysis of tear secretion 1 month after surgery. MAIN OUTCOME MEASURES: Schirmer's test without anesthesia, the topographic corneal irregularity measurement (CIM), the difference between attempted and achieved spherical equivalent, and the loss of best spectacle-corrected visual acuity. RESULTS: There was no difference in tear production 1, 3, or 6 months after LASIK in patients who had punctate epithelial erosions and rose bengal staining on the flap develop and those who did not. There was no significant difference in the CIM or mean accuracy of the refractive correction in the two groups, but some patients had a transient decrease in best spectacle-corrected visual acuity. Flap rose bengal staining resolved by 6 months after LASIK in most affected patients. CONCLUSIONS: LASIK-induced rose bengal staining in patients without preexisting dry eye is likely neurotrophic epitheliopathy, because there is no difference in mean tear production between patients who have significant punctate epithelial erosions and rose bengal staining develop on the flap and those who do not. The signs and symptoms of LASIK-induced (presumed) neurotrophic epitheliopathy tend to resolve approximately 6 months after surgery. This disorder tends to be more common and severe in patients with pre-existing dry eye disease.

Cornea↗

Metastatic risk for distinct patterns of postirradiation local recurrence of posterior uveal melanoma.

OBJECTIVE: The purpose of the study is to compare the prognostic significance of horizontal/marginal versus vertical/diffuse patterns of postirradiation local recurrence of posterior uveal melanoma. DESIGN: The study design was a nonrandomized, retrospective clinical study. Semiparametric and nonparametric statistical techniques were used. PARTICIPANTS: Seven hundred sixty-six posterior uveal melanoma patients were studied. INTERVENTION: Either iodine-125 plaque or helium ion radiation therapy was performed. MAIN OUTCOME MEASURES: Local tumor recurrence and systemic metastasis were measured. RESULTS: Local tumor recurrence was detected in 66 (8.6%) of 766 irradiated tumors. The 5-year actuarial rate of local recurrence was 10%. The recurrence pattem was horizontal/marginal in 27 patients (41%) and vertical/diffuse in 39 patients (59%). Systemic metastasis was detected in 5 patients (19%) with horizontal/marginal recurrence and in 19 patients (49%) with vertical/diffuse recurrence. After known metastatic risk factors were controlled, the relative risk for metastasis was 2.2 for horizontal/marginal recurrence and 5.1 for vertical/diffuse recurrence (P = 0.05). The actuarial rate of systemic metastasis was 2.9% per year for all patients, 6.3% per year for patients with horizontal/marginal recurrence, and 15.5% per year for patients with vertical/diffuse recurrence. CONCLUSIONS: Postirradiation local recurrence of posterior uveal melanoma is a risk factor for systemic metastasis. Vertical/diffuse recurrences may be associated more strongly with metastatic disease than horizontal/marginal recurrences.

Adult↗

An evaluation of olive-tree bark for the biological monitoring of airborne trace-elements at ground level.

There is a need to start looking into the possibility of tree bark for biomonitoring. Bark from olive trees (Olea europaea Linn.) has been collected over an area in northwestern Portugal, featuring a blend of rural lands, industrial towns and coastal environments. Samples were analysed through INAA and PIXE for their elemental contents. Results from both techniques were reconciled and then compared with an extensive database on 46 trace elements in Parmelia spp. thalli from the same sites and mostly from the very bark substrates. Distribution-free, nonparametric statistics show that, despite signal magnitude, variation patterns of bark and lichen concentrations follow one another in a most significant way. Selected elements in bark also correlate to a superior extent. As far as this investigation goes, there is no reason whatsoever for discarding bark as an alternative to lower epiphytes.

Databases, Factual↗

Clinical and psychological effects of intravenous diazepam related to plasma levels. A controlled, double-blind, cross-over study in oral surgery involving local analgesia.

In a controlled, double-blind, cross-over study with diazepam (DZ) and placebo (PL) various clinical, psychological, and pharmacological parameters were studied in 33 patients having identical impacted third molars removed. The patients were admitted to the study consecutively and nonparametric statistics were used throughout the study for the evaluation (Wilcoxon's matched-pairs signed test). The following aspects were examined: Continous reaction times (CRT), rating scales (a.m. Beecher), blood pressure, pulse, plasma concentration of DZ and of N-desmethyldiazepam, visual changes, amnesia, adverse reactions, recalling of duration of surgery, orientation in time, phlebitis, and final evaluation performed by the patient. The operative conditions were found to be excellent, and only a few adverse effects were noticed. The patients expressed an overall enthusiasm about the sedation. In the rating scales only the predominantly sedative items were affected and not the anxiolytic ones. Neither the heart rate nor the systolic blood pressure were significantly changed; on the contrary, the DZ-group was less affected than the PL-group when maximum increases in the systolic blood pressure were compared in the two groups. The continuous reaction times were significantly correlated to the plasma concentrations of diazepam, especially 1 hour after sedation. The reported recurrence of initial clinical symptoms 6 hours after sedation due to the N-desmethyldiazepam could not be demonstrated in this study. The CRT has proved itself to be of great value in discriminating between different kinds of cerebral affections; the patients with DZ-intoxication showed significantly faster CRT 1 hour after injection than did patients suffering from well-documented cerebral disorders such as organic brain damage or hepatic encephalopathia.

Adolescent↗

Nursing activities and outcomes of care in the assessment, management, and documentation of children's pain.

This study describes how assessment and documentation of children's acute postoperative pain is managed by nurses in university hospitals in Finland. A survey was conducted of 303 nurses working in children's wards of university-affiliated hospitals, and at the same time a retrospective chart review of 50 consecutive cases of operation of acute appendicitis was carried out. Charts were analyzed by content analysis, and the results of the survey are reported with percentage distribution and nonparametric statistical calculations. The results indicate that nurses assess pain mainly by observing the child's behavior and changes in physiology. Pain measurement instruments are rarely used, and nurses do not recognize them. The documentation of pain care is unsystematic and does not support the continuity of care. There is a clear need for development of assessment and documentation practices in the studied hospitals. Future research should look at the postoperative care of pain at home as well as care in non-university-affiliated hospitals.

Adolescent↗

Viscoelastic adherence to corneal endothelium following phacoemulsification.

PURPOSE: To compare the residual adherence of viscoelastics to the corneal endothelium following phacoemulsification in an in vitro rabbit model. SETTING: Departments of Ophthalmology and Anatomy, Wayne State University, Detroit, Michigan, USA. METHODS: Three groups of 10 rabbit eyes each had a lensectomy via phacoemulsification using sodium hyaluronate (Amvisc Plus, Healon GV) or sodium chondroitin sulfate-sodium hyaluronate (Viscoat) as the viscoelastic agent. After phacoemulsification and cortex removal, a central corneal block was excised, cryofixed, and processed for light and electron microscopy. Viscoelastic thickness was determined by a calibrated reticule on the light microscope or a calibrated measuring program in the electron microscope. The nonparametric statistical test, Kruskal-Wallis, was used to compare viscoelastic groups. RESULTS: Median phacoemulsification time between viscoelastic agents was not significantly different. Median viscoelastic thicknesses were 13.0 microns for Amvisc Plus, 0.4 micron for Healon GV, and 375.0 microns for Viscoat. Each was significantly different from the others (Kruskal-Wallis, P < .001). CONCLUSIONS: Median thickness of Amvisc Plus, Healon GV, and Viscoat remaining adherent to the corneal endothelium after phacoemulsification was markedly different. Viscoat provided the greatest amount of viscoelastic material adjacent to the corneal endothelium.

Animals↗

A clinical investigation of the efficacy of low level laser therapy in reducing orthodontic postadjustment pain.

Low level laser therapy (LLLT) has been shown to produce analgesic effects in many clinical applications. The aim of this clinical study was to test the efficacy of LLLT in controlling orthodontic postadjustment pain. Thirty-nine volunteers were selected for this study that used a double-blind design with placebo control. Elastomeric separators were placed at the proximal contacts of one premolar in each quadrant of the dentition to induce orthodontic pain. The tip of a 30 mW gallium-arsenide-aluminium (830 nm) diode laser probe was then placed at the buccal gingiva and directed at the middle third of the root. Three different treatment durations of 15, 30, and 60 seconds and one placebo treatment of 30 seconds were tested within each subject. The study was conducted over 5 days, and the visual analogue scale (VAS) was used to quantify the pain experienced by the subjects before and after laser applications for each day. Analysis of the VAS median scores showed that teeth exposed to laser treatment had lower levels of pain as compared with those with the placebo treatment. However, nonparametric statistical analysis of the data showed that the differences between treatments and placebo within each subject were not statistically significant.

Adult↗

Breath ethane in dialysis patients and control subjects.

Oxidant stress may play a role in the accelerated pathology of patients on dialysis, especially in the development of cardiovascular disease, which is a frequent condition in end-stage renal disease (ESRD) patients. Measurement of hydrocarbons can be employed to assess oxidant stress since breath hydrocarbons have been directly traced to in vivo breakdown of lipid hydroperoxides. We undertook to measure ethane, a major breath hydrocarbon, in 15 control subjects, 13 patients on peritoneal dialysis (PD), and 35 patients on hemodialysis (HD). Within the HD group, we separately examined 12 diabetic and 23 nondiabetic patients. Breath samples were collected after patients had breathed purified air for 4 min, and ethane content was measured by GC and expressed as pmoles/kg-body weight-minute (pmol/kg-min). As the data for the hemodialysis patients appeared skewed, nonparametric statistical techniques were employed to analyze these data, which are reported as median and interquartile range (IQR). Ethane levels were similar in 15 control subjects (median, 2.50 pmol [1.38-3.30]/kg-min] and 13 PD patients (median, 2.51 pmol [1.57-3.17]/kg-min). Breath ethane was significantly elevated in a portion (18 of 35 patients, 52%) of the HD patients (median, 6.16 pmol [4.46-8.88]/kg-min) (p <.001 vs. control, Mann-Whitney U test). Two of the diabetic HD patients showed extremely high values of breath ethane. Breath ethane was not altered by a single hemodialysis session, suggesting that long-term metabolic processes contribute to its elevation. Measurement of breath ethane may provide insight into severity of oxidant stress and metabolic disturbances, and provide guidance for optimal therapy and prevention of pathology in patients on long-term hemodialysis.

Adult↗

A numerical grading scale for peripheral nerve function.

A numerical grading scale for median and ulnar function is outlined. This system, based upon the known pathophysiology of chronic nerve compression, creates a hierarchical scale of mutually exclusive categories for motor and sensory function. The scale is responsive to incorporating new technologies for sensorimotor evaluation if these should offer advantages in computer-assisted evaluation, validity, or reliability. The scale is assumed to be nonuniform, and nonparametric statistical analysis, such as use of the Wilcoxon rank-sum test, is appropriate. Where motor function may predominate the peripheral nerve function, such as the ulnar nerve, in contrast to the median nerve, the scale may be uniquely defined to reflect this attribute. Pilot study examples of application of the numerical scoring system are given, and specific areas to better define the scale through research are suggested.

Carpal Tunnel Syndrome↗

Inter-relationships among sense of coherence, hope, and spiritual perspective (inner resources) of African-American and European-American breast cancer survivors.

This descriptive study compared sense of coherence (SOC), hope, and spiritual perspective in African-American and European-American breast cancer survivors. Five African-American and five European-American survivors completed multiple self-report instruments. Nonparametric statistical analyses included the Spearman rho and Mann-Whitney U tests. As hypothesized, there were significant positive relationships between SOC and spiritual perspective (r(s) =.768, p =.005) and hope and spiritual perspective (r(s) =.561, p =.046). There were no significant differences in SOC, hope, or spiritual perspective scores in the African-American compared with the European-American survivors. Results justify a larger study to explore inner resources of African-American breast cancer survivors.

Adult↗