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PubMed1999

Use of the TAT in the assessment of DSM-IV cluster B personality disorders.

The Social Cognition and Object Relations Scale (SCORS), developed by Western, Lohr, Silk, Kerber, and Goodrich (1985), is a diagnostic instrument used to assess an array of psychological functioning by using clinical narratives such as the Thematic Apperception Test (TAT; Murray, 1943) stories. This study investigated the utility of the SCORS to differentiate between Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) antisocial personality disorder (ANPD), borderline personality disorder (BPD), narcissistic personality disorder (NPD), and Cluster C personality disorder (CPD). A sample of 58 patients was separated into four groups: ANPD (n = 9), BPD (n = 21; 18 with a primary BPD diagnosis and 3 with prominent borderline traits who met 4 of the 5 DSM-IV criteria necessary for a BPD diagnosis), NPD (n = 16; 8 with a primary NPD diagnosis and 8 with prominent narcissistic traits who met 4 of the 5 DSM-IV criteria necessary for a NPD diagnosis), and CPD (n = 12). These groups were then compared on the 8 SCORS variables by using 5 TAT cards (1, 2, 3BM, 4, and 13MF). Spearman-Brown correction for 2-way mixed effects model of reliability for the 8 SCORS variables ranged from .70 to .95. The results of categorical and dimensional analyses indicate that (a) SCORS variables can be used to differentiate ANPD, BPD, and NPD; (b) the BPD group scored significantly lower (greater maladjustment) than did the CPD group on certain variables; (c) the BPD group scored significantly lower (greater maladjustment) than did the NPD group on all 8 SCORS variables; (d) the ANPD group scored significantly lower than did the NPD group on certain variables; (e) certain variables were found to be empirically related to the total number of DSM-IV ANPD, BPD, and NPD criteria; and (f) certain variables were found to be empirically related to Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) Personality disorder scales. The results of this study are discussed in terms of clinical utility, conceptual, and theoretical implications.

Adult↗
PubMed1990

Spatiotemporal contrast sensitivity differs in normal aging and Parkinson's disease.

We measured contrast sensitivity for static and laterally drifting vertical gratings in 12 young adults, 7 normal elderly adults, and 8 patients with Parkinson's disease (PD). We compared static and motion contrast sensitivity for spatial frequencies of 0.25, 1, and 4 cycles per degree (cpd), and temporal frequencies of 1, 3, and 9 Hz. Results show that normal aging leads to a reduction of motion sensitivity for the spatial frequency of 0.25 cpd. Compared with elderly controls, PD patients do not present specific abnormalities in this domain. However, for spatial frequencies of 1 and 4 cpd and temporal frequencies of 1 and 3 Hz, motion sensitivity is worse than static sensitivity in PD patients and not in elderly controls. These findings suggest a specific deficit of motion perception in PD, and possible dopaminergic involvement in the control of visuospatial behavior.

Adult↗
PubMed1989

Influence of right ventricular pressure overload on left and right ventricular filling in cor pulmonale assessed with Doppler echocardiography.

We evaluated the influence of right ventricular (RV) pressure overload on RV and left ventricular (LV) filling using Doppler echocardiography in cor pulmonale. The LV and RV inflow signals were recorded by Doppler flowmetry. The end-diastolic (ED) and end-systolic (ES) LV short axis images were detected by 2-dimensional echocardiography in 20 healthy subjects and in 36 cases of chronic pulmonary disease (CPD) with pulmonary hypertension. We measured (1) the ratio of the peak velocity of inflow due to atrial contraction to the peak velocity of rapid inflow (A/R), (2) the deceleration half-time of rapid inflow (delta TD), (3) the corrected radius of curvature (cRC) of the interventricular septum (IVS) at ES and ED, and (4) the percent change of length of 16 radial grids (%CL) using the fixed method on the ED and ES short axis images. In 17 of 36 patients with CPD, we measured the systolic pulmonary artery pressure (sPAP), the cardiac index (CI), the mean pulmonary capillary wedge pressure (mPCWP), the end-diastolic right ventricular pressure and the partial oxygen pressure of arterial blood (PaO2). The results were as follows: in CPD, (1) both the RV and the LV diastolic behavior were impaired as shown by increased A/R (1.04 +/- 0.20, 0.98 +/- 0.17, respectively) and prolonged delta TD (115 +/- 20, 100 +/- 17 msec, respectively), (2) the IVS was flattened at ED (cRC of IVS = 0.67 +/- 0.12), (3) the IVS wall motion was impaired (%CL of IVS = 133 +/- 13), (4) the sPAP had an adequate correlation with RV A/R (r = 0.80, p less than 0.01), RV delta TD (r = 0.59, p less than 0.05), LV A/R (r = 0.82, p less than 0.01), LV delta TD (r = 0.61, p less than 0.05), cRC of IVS (r = 0.67, p less than 0.01), %CL of IVS (r = -0.59, p less than 0.05). There was no significant correlation between the LV diastolic behavior and the CI, the mPCWP, the PaO2. It is concluded that the impairment of RV diastolic behavior was caused by the decreased RV compliance due to RV free wall hypertrophy. Moreover, the RV pressure overload interfered with the IVS motion during diastole, this regional impairment of diastolic behavior of the IVS subsequently causing impairment of LV diastolic filling.

Adolescent↗
PubMed1993

A study of sister chromatid exchange and somatic cell mutation in hospital workers exposed to ethylene oxide.

To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Department (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison group from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on genetic test results for the 94 CPD and matched NUTR workers only. Statistical analysis based on the mean SCE frequency in the top 5, top 10, and all cells (50 cells scored per individual) and high frequency cells (HFC) based on the 95th percentile for nonsmoking control subjects showed a direct association with current smoking but not with EO exposure. Similarly, statistical analysis of the somatic cell mutation (SCMT) variant frequencies did not demonstrate an association with EO exposure, nor with smoking. Regression analysis indicated that sex was the only other covariate that significantly affected SCE. Age was weakly associated with SCMT. A statistically significant interaction between occupational exposure and smoking habits was observed only for the mean SCE frequency of the top 5 and top 10 cells when the 11 current CPD/NUTR pairs were not included. Thus, this interaction should be interpreted with caution.

Ethylene Oxide↗
PubMed1979

Spatial frequency masking in human vision: binocular interactions.

Binocular contrast interactions in human vision were studied psychophysically. Thresholds were obtained for sinewave grating stimulation of the right eye in the presence of simultaneous masking gratings presented to the right eye (monocular masking) or left eye (dichoptic masking). In the first experiment, thresholds were measured at 0.25, 1.0, 4.0, and 16.0 cycle per degree (cpd) as a function of the contrast of masking gratings of identical frequency and phase. Thresholds rose nonmonotonically with masking contrast. At medium and high contrast levels, dichoptic masking was more effective in elevating contrast thresholds than monocular masking, and approached Weber's Law behavior. In the second experiment, spatial frequency tuning functions were obtained for test gratings at five spatial frequencies, by measuring threshold elevation as a function of the spatial frequency of constant-contrast masking gratings. At 1.0, 4.0, and 16.0 cpd, the tuning functions peaked at the test frequencies. The dichoptic tuning functions had a bandwidth of about 1 octave between half-maximum points, narrower than +/- 1 octave bandwidths of the monocular tuning functions. At 0.125 and 0.25 cpd, the tuning functions were broader and exhibited a shift in peak masking to frequencies above the test frequencies.

Adult↗
PubMed1984

Orientation bandwidths of spatial mechanisms measured by masking.

Orientation tuning curves were measured at 10 spatial frequencies ranging from 0.5 to 11.3 cycles per degree (cpd) using a masking paradigm. The stimuli were spatially localized test patterns of 1.0 octave bandwidth superimposed upon cosine grating masks. By using a model that corrects for the nonlinearity inherent in the masking process, we obtain the half-amplitude half-bandwidths (theta 1/2) of Cartesian-separable receptive fields that may underlie orientation selectivity. Additional experiments show that the data are not compatible with separability in polar coordinates (spatial frequency and orientation). The orientation half-bandwidths have been found to decrease somewhat with increasing spatial frequency, going from about 30 degrees at 0.5 cpd to 15 degrees at 11.3 cpd, for both sustained and transient forms of temporal modulation. Similar bandwidths are obtained from data where the test is oriented along 45 degrees. These bandwidth estimates are shown to be consistent with subthreshold summation data as well as physiological data from monkey striate cortex.

Animals↗
PubMed1997

Orientation tuning of the spatial-frequency-tuned mechanisms of the red-green channel.

Significant orthogonal masking for color stimuli [Invest. Ophthalmol. Visual Sci. 34, 782 (No. 405-54) (1993)] but not for achromatic stimuli [J. Opt. Soc. Am. A 1, 226 (1984)] under sustained presentation led us to investigate the orientation tuning of the spatial-frequency- (SF-) tuned color mechanisms. The Red-Green channel was isolated from the achromatic channel by the minimum flicker technique and from the Yellow-Blue channel by the hue cancellation technique. Contrast sensitivity functions, threshold elevation versus mask orientation curves (measured by orientation masking), and threshold elevation versus mask contrast curves were measured by the method of constant stimuli and a two-interval forced-choice technique on two normal observers. Test targets were spatially localized (D6), vertical color patterns, and masks were sinusoidal color patterns oriented 15 degrees-90 degrees from the vertical in 15 degrees steps and had the same SF's as those of test patterns. Mask contrasts were varied between 1.2% and 60%. The orientation tuning curves of the SF-tuned color mechanisms were extracted by obtaining the best fit to contrast sensitivity and threshold elevation data simultaneously at a given SF with use of the masking model. Results show that threshold elevations depend on test SF, mask SF, mask orientation, and mask contrast. Half-bandwidths at half-height (with respect to 15 degrees from the vertical) of threshold elevation versus mask orientation curves range from 90 degrees to 29 degrees depending on SF's. The slopes of threshold elevation versus mask contrast curves range from 0.76 to 0.29 on octave-octave coordinates depending on SF's. Orientation half-bandwidths at half-height of orientation tuning curves of the SF-tuned color mechanisms (1) range from 79 degrees to 28 degrees and (2) average from 68 degrees to 30 degrees for SF's 0.063-8 cycles per degree (cpd). Data suggest that the orientation tuning curves of the SF-tuned chromatic mechanisms are broader (except at 2 cpd) than those of the achromatic mechanisms (orientation half-bandwidths: 32 degrees-15 degrees for 0.5-11.3 cpd [J. Opt. Soc. Am. A 1, 226 (1984)]); moreover, the orientation bandwidths are SF dependent.

Algorithms↗
PubMed1999

Modulation frequency and orientation tuning of second-order texture mechanisms.

Modulation frequency and orientation tuning of second-order mechanisms underlying the detection of modulation in local spatial-frequency information are assessed by using an oblique-masking paradigm. Stimuli were Gabor-filtered noise patterns in which the local carrier spatial frequency was modulated about an average value of 4.7 cycles per degree (cpd) according to sinusoidal function. Thresholds were determined for spatial-frequency modulated test patterns (0.2 and 0.8 cpd) with fixed vertical carrier and modulation orientations presented alone and in the presence of spatiotemporally superimposed masks. Mask modulation frequency (0.1, 0.2, 0.4, 0.8, or 1.6 cpd), modulation orientation (0 degree, 45 degrees, or 90 degrees relative to vertical), and carrier orientation (18.5 degrees or 90 degrees relative to vertical) were manipulated independently while the mask modulation amplitude remained fixed at 0.25. Manipulating the modulation frequency of the mask revealed some modulation frequency specificity, particularly at lower test modulation frequencies. Spatial-frequency modulated masks produced threshold elevations regardless of the local carrier orientation. However, there was no evidence of threshold elevation when the mask modulation orientation was orthogonal to that of the test pattern. These results suggest a second-order texture mechanism that is tuned to both modulation frequency and modulation orientation but is not selective in terms of the orientation of first-order inputs.

Contrast Sensitivity↗
PubMed2006

Teaching and continuing professional development: an Italian experience.

Continuing Professional Development (CPD) is a key factor for effective implementation of Clinical Governance. The development of a quality system is, in fact, strictly related to the development of competencies of healthcare professionals. Lifelong learning has emerged as a new paradigm that underlines the need to maintain and continuously improve knowledge, competencies and attitudes in the changing scenario of healthcare systems. CPD accreditation is another fundamental issue and a variety of voluntary and compulsory approaches can be recognised at an international level. The experience of the University Hospital of Padova may be useful to demonstrate that CPD can be addressed to implement a Clinical Governance project.

Education, Medical, Continuing↗
PubMedDate not supplied

Hypopituitarism and chorioretinopathy in two siblings.

Two male siblings with chorioretinopathy and pituitary dysfunction (CPD) were found to have empty sellas on CT scan. Extensive ophthalmological and endocrinological investigation revealed the absence of gonadotrophins in both brothers and growth hormone deficiency in one. ACTH, TSH, and posterior pituitary function were normal. Karyotyping in one brother revealed a 46XY complement. Ophthalmological evaluation of three other siblings and both parents revealed normal vision and no evidence of retinopathy. The brothers represent two additional examples of CPD syndrome, suggesting a genetic etiology for this syndrome complex. The empty sellas present add another facet to the central nervous system disorders found in CPD syndrome.

Adolescent↗
PubMed2001

Alexithymia in patients with major depressive disorder and comorbid cluster C personality disorders: a 6-month follow-up study.

The authors examined the association between alexithymia, cluster C personality disorders (CPD), and severity of depression among 121 outpatients with major depressive disorder (MDD) in a 6-month, follow-up study. Diagnosis of depression and CPD was confirmed by means of the Structured Clinical Interviews for DSM-III-R (SCID I and SCID II). Alexithymia was screened using the 20-item version of the Toronto Alexithymia Scale and severity of depression was assessed using the 21-item Beck Depression Inventory. Results indicated that alexithymic features are common in patients with MDD but often alleviated during recovery from depression. Moreover, comorbid CPD and severity of depression seemed to be associated with poorer recovery from alexithymia. The implications of these findings are discussed.

Adult↗
PubMed2001

Effectiveness of a high school smoking cessation program.

OBJECTIVE: To evaluate the impact of a school-based smoking cessation program targeting adolescents interested in quitting. DESIGN: Randomized clinical trial over one school year. SETTING: Large public high school. PARTICIPANTS: Students interested in quitting smoking. INTERVENTION: Seventy-four students were randomized to receive either: 1) a 6-week, 8-session, classroom-based, smoking cessation curriculum designed for adolescents (n = 35) or 2) an informational pamphlet on how to quit smoking with promise of the classroom curriculum in 3 months (n = 39). OUTCOME MEASURES: Change in smoking behavior measured by: 1) self-reported smoking cessation and exhaled carbon monoxide <6 parts per million (smoke-free); 2) self-reported quit attempts; and 3) change in cigarettes per day (cpd) at the end of the 6-week curriculum and then 4, 10, and 20 weeks later. Saliva cotinine was also measured at these points to validate these outcome measures. Analysis. Intention-to-treat. RESULTS: Participants in the classroom group attended an average of 4.4 sessions. At the end of the curriculum, the classroom group was significantly more likely to be smoke-free (59% vs 17%), to have tried to quit smoking (82% vs 54%), and to reduce mean cpd (7.0 vs 1.0). Four weeks later, these differences persisted: smoke-free (52% vs 20%), quit attempt (85% vs 60%), and reduction in mean cpd (6.6 vs 1.6). Changes in saliva cotinine were consistent with reported outcome measures; those who were smoke-free had a significant reduction in saliva cotinine at the end of the intervention, and at 4 weeks. At 10 and 20 weeks after the curriculum, 41% and 31%, respectively, of the classroom group remained smoke-free. Once participants in the pamphlet group underwent the classroom intervention (average attendance of 2.2 sessions) their cessation rates were similar to the initial group: 31% at the end of the curriculum and 27% 10 weeks later. CONCLUSION: A school-based curriculum for adolescent smoking cessation is more effective than an informational pamphlet alone and reduces cigarette use by adolescents. More research is needed to test the reproducibility, sustainability, and generalizability of this curriculum to offer more smoking cessation options to teenagers.

Adolescent↗
PubMed2005

Safety and efficacy of the nicotine patch and gum for the treatment of adolescent tobacco addiction.

OBJECTIVES: To determine the safety and efficacy of the nicotine patch and gum for adolescents who want to quit smoking. DESIGN: Double-blind, double-dummy, randomized, 3-arm trial with a nicotine patch (21 mg), nicotine gum (2 and 4 mg), or a placebo patch and gum; all participants received cognitive-behavioral group therapy. SETTING: Inner-city, outpatient clinic on the East Coast. Subjects. Thirteen- to 17-year-old adolescents who smoked > or =10 cigarettes per day (CPD), scored > or =5 on the Fagerstrom Test of Nicotine Dependence, and were motivated to quit smoking. Intervention. Twelve weeks of nicotine patch or gum therapy with cognitive-behavioral therapy, with a follow-up visit at 6 months (3 months after the end of treatment). MAIN OUTCOME MEASURES: Safety assessed on the basis of adverse event reports for all 3 groups, prolonged abstinence, assessed through self-report and verified with exhaled carbon monoxide (CO) levels of < or =6 ppm, in intent-to-treat analyses, and smoking reduction (CPD and thiocyanate concentrations) among trial completers. RESULTS: A total of 120 participants were randomized (72% white, 70% female; age: 15.2 +/- 1.33 years; smoking: 18.8 +/- 8.56 CPD; Fagerstrom Test of Nicotine Dependence score: 7.04 +/- 1.29) from 1999 to 2003. Participants started smoking at 11.2 +/- 1.98 years of age and had been smoking daily for 2.66 +/- 1.56 years; 75% had at least 1 current psychiatric diagnosis. Mean compliance across groups was higher for the patch (mean: 78.4-82.8%) than for the gum (mean: 38.5-50.7%). Both the patch and gum were well tolerated, and adverse events were similar to those reported in adult trials. Changes in mean saliva cotinine concentrations throughout treatment were not statistically significant. Intent-to-treat analyses of all randomized participants showed CO-confirmed prolonged abstinence rates of 18% for the active-patch group, 6.5% for the active-gum group, and 2.5% for the placebo group; the difference between the active-patch and placebo arms was statistically significant. There was no significant effect of patch versus gum or gum versus placebo on cessation outcomes. Abstinence rates at the 3-month follow-up assessment were sustained but were not significantly associated with treatment group. Mean smoking rates, but not CO or thiocyanate concentrations, decreased significantly in all 3 arms but not as a function of treatment group. CONCLUSIONS: Nicotine patch therapy combined with cognitive-behavioral intervention was effective, compared with placebo, for treatment of tobacco dependence among adolescent smokers. Decreases in the numbers of cigarettes smoked appeared to be offset by compensatory smoking. Additional study of nicotine gum, with enhanced instructional support, is needed to assess its efficacy among adolescent smokers.

Administration, Cutaneous↗
PubMed2000

Effects of cytosine methylation on pyrimidine dimer formation in DNA.

The relative induction of cyclobutane pyrimidine dimers (CPD) and pyrimidine (6-4)pyrimidone photoproducts ([6-4]PD) was quantified in the duplex homopolymers polydeoxyadenosine:polydeoxythymidine, polydeoxyguanosine:polydeoxycytidine and polydeoxyguanosine:polydeoxy-5-methylcytidine irradiated with UVC or UVB radiation. Cytosine methylation significantly increased the yield of cytosine (6-4)PD after irradiation with UVC light and of cytosine CPD and (6-4)PD after irradiation with UVB light. The data suggest that CPD and (6-4)PD are preferentially induced at 5-methylcytosine bases in DNA of cells exposed to sunlight and comprise a major component of the mutation spectrum leading to the initiation of sunlight-induced skin cancer.

Cytosine↗
PubMed2000

Damage to DNA in bacterioplankton: a model of damage by ultraviolet radiation and its repair as influenced by vertical mixing.

A model of UV-induced DNA damage in oceanic bacterioplankton was developed and tested against previously published and novel measurements of cyclobutane pyrimidine dimers (CPD) in surface layers of the ocean. The model describes the effects of solar irradiance, wind-forced mixing of bacterioplankton and optical properties of the water on net DNA damage in the water column. The biological part includes the induction of CPD by UV radiation and repair of this damage through photoreactivation and excision. The modeled damage is compared with measured variability of CPD in the ocean: diel variation in natural bacterioplankton communities at the surface and in vertical profiles under different wind conditions (net damage as influenced by repair and mixing); in situ incubation of natural assemblages of bacterioplankton (damage and repair, no mixing); and in situ incubation of DNA solutions (no repair, no mixing). The model predictions are generally consistent with the measurements, showing similar patterns with depth, time and wind speed. A sensitivity analysis assesses the effect on net DNA damage of varying ozone thickness, colored dissolved organic matter concentration, chlorophyll concentration, wind speed and mixed layer depth. Ozone thickness and mixed layer depth are the most important factors affecting net DNA damage in the mixed layer. From the model, the total amplification factor (TAF; a relative measure of the increase of damage associated with a decrease in ozone thickness) for net DNA damage in the euphotic zone is 1.7, as compared with 2.1-2.2 for irradiance weighted for damage to DNA at the surface.

Animals↗
PubMed2003

Pyrimidine dimer formation and oxidative damage in M13 bacteriophage inactivation by ultraviolet C irradiation.

The mechanism by which UV-C irradiation inactivates M13 bacteriophage was studied by analyzing the M13 genome using agarose gel electrophoresis and South-Western blotting for pyrimidine dimers. The involvement of singlet oxygen (1O2) was also investigated using azide and deuterium oxide and under deoxygenated conditions. With a decrease in M13 infectivity on irradiation, single-stranded circular genomic DNA (sc-DNA) was converted to Form I and Form II, which had an electrophoretic mobility between that of sc-DNA and linear-form DNA. However, the amount of sc-DNA remaining was not correlated with the survival of M13. The formation of cyclobutane pyrimidine dimers (CPD) and pyrimidine (6-4) pyrimidone photoproducts ((6-4)PP) increased as a function of irradiation dose. The decrease in M13 infectivity was highly correlated with the increase in CPD and (6-4)PP, whereas no change was seen in M13 coat protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 8-Oxo-7,8-dihydro-2'-deoxyguanosine did not form in the M13 genome after UV-C irradiation. Inactivation of M13 was neither enhanced by deuterium oxide nor inhibited by azide. Deoxygenation of the M13 suspension did not affect the inactivation, indicating that 1O2 did not participate in the inactivation of M13 by UV-C irradiation under these conditions. These results indicated that UV-C irradiation induced not only CPD and (6-4)PP formation but also additional tertiary structural change in DNA inside the M13 virions, resulting in primary damage and a loss of infectivity. The indirect effect of UV-C irradiation such as 1O2 production followed by oxidative damage to nucleic acids and proteins might have contributed less, if at all, to the inactivation of M13 than the direct effect of UV-C.

Bacteriophage M13↗
PubMed2005

Radial frequency stimuli and sine-wave gratings seem to be processed by distinct contrast brain mechanisms.

An assumption commonly made in the study of visual perception is that the lower the contrast threshold for a given stimulus, the more sensitive and selective will be the mechanism that processes it. On the basis of this consideration, we investigated contrast thresholds for two classes of stimuli: sine-wave gratings and radial frequency stimuli (i.e., j0 targets or stimuli modulated by spherical Bessel functions). Employing a suprathreshold summation method, we measured the selectivity of spatial and radial frequency filters using either sine-wave gratings or j0 target contrast profiles at either 1 or 4 cycles per degree of visual angle (cpd), as the test frequencies. Thus, in a forced-choice trial, observers chose between a background spatial (or radial) frequency alone and the given background stimulus plus the test frequency (1 or 4 cpd sine-wave grating or radial frequency). Contrary to our expectations, the results showed elevated thresholds (i.e., inhibition) for sine-wave gratings and decreased thresholds (i.e., summation) for radial frequencies when background and test frequencies were identical. This was true for both 1- and 4-cpd test frequencies. This finding suggests that sine-wave gratings and radial frequency stimuli are processed by different quasi-linear systems, one working at low luminance and contrast level (sine-wave gratings) and the other at high luminance and contrast levels (radial frequency stimuli). We think that this interpretation is consistent with distinct foveal only and foveal-parafoveal mechanisms involving striate and/or other higher visual areas (i.e., V2 and V4).

Adult↗
PubMed1999

Intermittent versus continuous intraperitoneal glycopeptide/ceftazidime treatment in children with peritoneal dialysis-associated peritonitis. The Mid-European Pediatric Peritoneal Dialysis Study Group (MEPPS).

Intermittent intraperitoneal antibiotic administration appears as a practical and economical therapeutic concept in continuous peritoneal dialysis (CPD)-related peritonitis, but the equivalence of this principle with standard continuous treatment awaits confirmation by prospective, randomized clinical trials. This study evaluates the efficacy, safety, and clinical acceptance of an initial combination treatment including a glycopeptide (vancomycin or teicoplanin) and ceftazidime, each applied either intermittently or continuously, in a cohort of pediatric patients with CPD-related peritonitis. Patients randomized for continuous treatment received an intraperitoneal loading dose of glycopeptide and ceftazidime followed by maintenance doses added to each dialysate bag. In the intermittent treatment groups, the glycopeptide was administered in two loading doses 7 d apart, and ceftazidime during one dialysis cycle per day. Initial treatment response was evaluated after 60 h by the change in a Disease Severity Score and by the clinical decision to continue initial treatment. Of 152 patients observed for a total of 234 patient years, 90 patients developed 195 episodes of peritonitis (including 27 relapses within 4 wk after end of treatment). Dialysate cultures were positive in 83% of the episodes. In gram-positive peritonitis (79% of culture-positive cases), the primary success (overall 95%) and relapse rates (21%) were not different between continuous and intermittent, or between vancomycin and teicoplanin treatment. Oversensitivity reactions occurred in three and ototoxicity in one vancomycin-treated patient, whereas no such side effects were observed with teicoplanin. Residual renal function declined during peritonitis episodes regardless of treatment modality. In gram-negative peritonitis (18% of cases), intermittent ceftazidime treatment was less successful than continuous treatment according to clinical judgment (3 of 11 versus 10 of 14, P < 0.05), but not when rated by Disease Severity Score (8 of 11 versus 12 of 14). In conclusion, intermittent and continuous intraperitoneal treatment of CPD-related peritonitis with glycopeptides and ceftazidime is equally efficacious and safe when measured by objective clinical criteria. This contrasts with a strong tendency of clinicians to move from intermittent to continuous treatment in severe peritonitis.

Adolescent↗