Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CPD”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources

Visual acuity and contrast sensitivity comparison between Tecnis and AcrySof SA60AT intraocular lenses: A multicenter randomized study.

PURPOSE: To evaluate best corrected visual acuity (BCVA) and photopic and mesopic contrast sensitivity in pseudophakic patients implanted either with the aspheric intraocular lens (IOL) designed to correct for corneal spherical aberration or with a conventional IOL. SETTING: Three surgical centers participated this prospective randomized masked comparative study. METHODS: Thirty eyes of 30 patients after aspheric lens implantation (Pfizer/Pharmacia Tecnis Z9000) were compared with 30 eyes of 30 age-matched patients after conventional lens implantation (Alcon AcrySof SA60AT). Two to three months after surgery, best spectacle corrected distance visual acuity was measured using the Early Treatment Diabetic Retinopathy Study chart. Contrast sensitivity was measured by sinusoidal grating charts for distance at photopic (85 cd/m(2)) and mesopic (6 cd/m(2)) luminance level with optical correction in place. Tested spatial frequencies were 1.5, 3, 6, 12, and 18 cycles per degree (cpd). RESULTS: The mean BCVA was -0.053 +/- 0.044 logMAR in eyes with the aspheric Tecnis IOL and 0.006 +/- 0.059 logMAR in eyes with the conventional AcrySof IOL (P=.0001). Eyes with the aspheric IOL showed better contrast sensitivity at spatial frequencies of 3 cpd (P<.05) and 6, 12, and 18 cpd (P<.01) in photopic and in mesopic conditions. Peak improvement occurred at 18 cpd and was 36% (0.29 log units) in photopic and 54% (0.27 log units) in mesopic conditions. CONCLUSIONS: The aspheric Tecnis IOL yielded better BCVA and better distance contrast sensitivity than the conventional IOL. The differences were clinically significant for higher spatial frequencies. The results give some suggestions for further studies.

Aged↗

1,25-Dihydroxyvitamin D and three low-calcemic analogs decrease UV-induced DNA damage via the rapid response pathway.

1,25-Dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] is anti-apoptotic in human keratinocytes, melanocytes and fibroblasts after ultraviolet (UV)-exposure. To date, there is no published data on the effects of 1,25(OH)(2)D(3) or its analogs on DNA damage in irradiated skin cells. In these skin cells, 24h pre-treatment with 1,25(OH)(2)D(3) dose-dependently (10(-12) to 10(-8)M) decreased CPD damage by up to 60%. This photoprotective effect was also seen if the 1,25(OH)(2)D(3) was added immediately after irradiation and was mimicked by QW-1624F2-2 (QW), a low-calcemic 1beta-hydroxymethyl-3-epi-16-ene-24,24-difluoro-26,27-bis homo hybrid analog. The well-studied low calcemic, rapid acting agonist analogs 1alpha,25(OH)(2)lumisterol(3) (JN) and 1alpha,25(OH)(2)-7-dehydrocholesterol (JM) also protected skin cells from UV-induced cell loss and CPD damage to an extent comparable with that of 1,25(OH)(2)D(3). In contrast, the rapid response antagonist analog 1beta,25(OH)(2)D(3) (HL) completely abolished the photoprotective effects (reduced cell loss and reduced CPD damage) produced by treatment with 1,25(OH)(2)D(3), JN, JM and QW. Evidence for involvement of the nitric oxide pathway in the protection from CPD damage by 1,25(OH)(2)D(3) was obtained. These data provide further evidence for a role of the vitamin D pathway in the intrinsic skin defenses against UV damage. The data also support the hypothesis that the photoprotective effects of 1,25(OH)(2)D(3) are mediated via the rapid response pathway(s).

Apoptosis↗

In vivo relevance for photoprotection by the vitamin D rapid response pathway.

Vitamin D is produced by exposure of 7-dehydrocholesterol in the skin to UV irradiation (UVR) and further converted in the skin to the biologically active metabolite, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) and other compounds. UVR also results in DNA damage producing cyclobutane pyrimidine dimers (CPD). We previously reported that 1,25(OH)(2)D(3) at picomolar concentrations, protects human skin cells from UVR-induced apoptosis, and decreases CPD in surviving cells. 1,25(OH)(2)D(3) has been shown to generate biological responses via two pathways-the classical steroid receptor/genomic pathway or a rapid, non-genomic pathway mediated by a putative membrane receptor. Whether the rapid response pathway is physiologically relevant is unclear. A cis-locked, rapid-acting agonist 1,25(OH)(2)lumisterol(3) (JN), entirely mimicked the actions of 1,25(OH)(2)D(3) to reduce fibroblast and keratinocyte loss and CPD damage after UVR. The effects of 1,25(OH)(2)D(3) were abolished by a rapid-acting antagonist, but not by a genomic antagonist. Skh:hr1 mice exposed to three times the minimal erythemal dose of solar-simulated UVR and treated topically with 1,25(OH)(2)D(3) or JN immediately after UVR showed reduction in UVR-induced UVR-induced sunburn cells (p<0.01 and <0.05, respectively), CPD (p<0.01 for both) and immunosuppression (p<0.001 for both) compared with vehicle-treated mice. These results show for the first time an in vivo biological response mediated by a rapid-acting analog of the vitamin D system. The data support the hypothesis that 1,25(OH)(2)D(3) exerts its photoprotective effects via the rapid pathway and raise the possibility that other D compounds produced in skin may contribute to the photoprotective effects.

Cells, Cultured↗

Computer-assisted instruction improves clinical reasoning skills of dietetics students.

OBJECTIVE: The effects of a computer-assisted instruction (CAI) tutorial program on learning clinical reasoning skills were compared in undergraduate dietetics students. DESIGN: A drill-and-practice program to control for time on task, and tutorial program, and a simulation program, as the test vehicle, were developed. The tutorial and simulation programs presented data on a patient with cardiovascular disease. SETTING: Subjects were tested in 30 undergraduate dietetics programs. SUBJECTS: Participants were 413 undergraduate diet therapy students enrolled in a coordinated program in dietetics (CPD) or a didactic program in dietetics (DPD). INTERVENTION: After completion of lectures on cardiovascular disease, subjects were given the drill-and-practice program plus a simulation test (group 1), the tutorial plus a simulation test (group 2), or the simulation test only (group 3). MAIN OUTCOME MEASURES: Scores on the simulation test were compared. Variables included type of CAI, dietetics program, year in school, computer experience, and experience using a medical chart. Mastery of objectives related to lower- and higher-level clinical reasoning skills introduced in the tutorial program was computed. STATISTICAL ANALYSIS: One-way analysis of variance and Student-Newman Keuls tests were conducted to determine any differences among the three groups. Reliability was determined using the Kuder-Richardson Formula 20. RESULTS: The reliability coefficient of the stimulation test was 0.93. Group 2 higher on the simulation test than group 1 or group 3. As a group, the CPD students scored higher than the DPD students. When CPD and DPD students were divided into the three experimental groups, there was no significant difference between the CPD and DPD student simulation scores. Group 2 mastered all objectives for lower-level reasoning skills and the higher-level decision-making objective better than groups 1 and 3. APPLICATIONS/CONCLUSIONS: A computer tutorial program enhanced clinical reasoning skills in undergraduate dietetics students. This type of program could be used to supplement many topics taught in diet therapy and provide DPD students with experimental learning before their clinical intern practicums.

Analysis of Variance↗

Dorzolamide hydrochloride and visual function in normal eyes.

PURPOSE: To determine by a pilot study whether standard treatment with the topical carbonic anhydrase inhibitor dorzolamide hydrochloride influences visual function under normal breathing conditions, during carbon dioxide inhalation, or during hyperventilation, and to establish criteria for future larger-scale studies. METHODS: We enrolled 12 normal subjects into this randomized double-masked placebo-controlled crossover study. Each subject was treated with either dorzolamide 2% or placebo, three times daily, for 4 days. After a 2-week washout period, the alternative topical agent was used under identical testing conditions. On day 2 of each treatment phase, contrast sensitivities to sinusoidal gratings of 1 and 4 cycles per degree (cpd) were assessed. On day 4, mean deviation values from full-threshold 10-2 visual fields were obtained. Three sets of each visual function test were obtained before each treatment phase, and in sequence on each testing day, during normal breathing (baseline), inhalation of carbon dioxide-enriched air, and hyperventilation while intraocular pressure was monitored. RESULTS: Contrast sensitivity at 4 cpd decreased significantly (P < .01) during carbon dioxide supplementation with placebo but showed no significant change with dorzolamide. The decrease in contrast sensitivity accompanying hyperventilation was attenuated (by nearly 50% at 1 cpd) during dorzolamide treatment. Dorzolamide treatment was associated with higher perimetry mean deviation values under each treatment condition and was statistically significant (P < .05) at baseline. CONCLUSIONS: Dorzolamide appears to enhance contrast sensitivity in normal subjects during physiologic hypercapnia and hypocapnia at 4 and 1 cpd, respectively. Also, under normal breathing conditions, dorzolamide therapy increases perimetric light sensitivity.

Adult↗

Laboratory evaluation of the entomopathogenic fungus, Metarhizium anisopliae for the control of the groundnut bruchid, Caryedon serratus on groundnut.

The pathogenicity of five isolates of Metarhizium anisopliae to adult Caryedon serratus was evaluated in the laboratory. All the isolates tested were virulent to the beetle but pathogenicity varied among the isolates. One isolate, CPD 4 was consistently superior to all other isolates in terms of mortality of the beetle, protection of groundnut pods from damage, reduction in progeny production and repellency to the beetle. At 10 days post-treatment, adult mortality treated with 0.1, 0.5 and 1.0g of dry conidia equivalent to 3.6x10(8), 1.8x10(9) and 3.6x10(9) conidia of isolate CPD 4 per 50g of groundnut pods was 100% which did not differ significantly from pirimiphos-methyl-treated pods at 10ppm. At the lowest dosage of 0.1g of conidia per 50g of pods, damage in pods protected with isolate CPD 4 was 5% which did not differ significantly from the 2% damage in pods protected by pirimiphos-methyl at 10ppm but significantly differed from damage in untreated pods which was 26%. Isolate CPD 4 caused complete reduction in progeny emergence at all dosages tested. It also exhibited some degree of repellency to the beetle with percentage repellency values of between 40-79% at concentrations of 0.1-1.0g of conidia per 50g of groundnut pods. These combined virulence and repellency characteristics of this isolate may increase its protectant potential against C. serratus.

Journal Article↗

Central performance drop in texture segmentation: the role of spatial and temporal factors.

Previous studies reported that performance in texture segmentation was lower near the fovea than in the periphery. However, the exact cause of this phenomenon had been unknown. Experiment 1 replicated the central performance drop (CPD). Experiments 2 and 3 demonstrated that the previously reported CPD was due to a temporal factor, i.e. slower neural processing in central vision, rather than a spatial factor. But Experiments 4 and 5 showed that certain textures can lead to a purely spatial form of CPD due to inhibition and/or interference from high spatial frequency mechanisms in central vision. This study showed that, depending on textures, CPD can arise from either temporal or spatial causes.

Analysis of Variance↗

The role of spatial frequency in color induction.

Color induction was measured for test and inducing chromaticities presented in spatial square-wave alternation, with spatial frequencies of 0.7, 4.0, 6.0 and 9.0 cpd. Observers matched the test chromaticities to a rectangular matching field using haploscopic presentation. Data were collected and analyzed within the framework of a cone chromaticity space, allowing analysis of spatial frequency effects on post-receptoral spectral opponent pathways. Assimilation, a shift of chromaticity toward the inducing chromaticity, was found at the highest spatial frequency (9.0 cpd). Contrast, a shift of chromaticity away from the inducing chromaticity, occurred at the lowest spatial frequency (0.7 cpd). The spatial frequency at the transition point from assimilation to contrast was near 4 cpd, independent of the cone axis. Assimilation was unaffected by the presence of a neutral surround and could be described by a spread light model. Contrast was reduced in the presence of a neutral surround. The data suggested that retinal contrast signals are important determinants in the perception of chromatic contrast.

Adult↗

Temporal sensitivity of human luminance pattern mechanisms determined by masking with temporally modulated stimuli.

Target contrast thresholds were measured using vertical spatial Gabor targets in the presence of full field maskers of the same spatial frequency and orientation. In the first experiment both target and masker were 2 cpd. The target was modulated at a frequency of 1 or 10 Hz and the maskers varied in temporal frequency from 1 to 30 Hz and in contrast from 0.03 to 0.50. In the second experiment both target and masker had a spatial frequency of 1, 5 or 8 cpd. The target was modulated at 7.5 Hz and the same set of maskers was used as in the first experiment. The results are not consistent with a widely used model that is based on mechanisms in which excitation is summed linearly and the sum is transformed by an S-shaped nonlinear excitation-response function. A new model of human pattern vision mechanisms, which has excitatory and divisive inhibitory inputs, describes the results well. Parameters from the best fit of the new model to the results of the first experiment show that the 1 Hz and 10 Hz targets were detected by mechanisms with temporal low-pass and band-pass excitatory sensitivity, respectively. Fits to the second experiment suggest that at 1 cpd, the excitatory tuning of the detecting mechanism is band-pass. At 5 and 8 cpd, the mechanisms are excited by a broad range of temporal frequencies. Mechanism sensitivity to divisive inhibition depends on temporal frequency in the same general way as sensitivity to excitation. Mechanisms are more broadly tuned to divisive inhibition than to excitation, except when the target temporal frequency is high.

Adult↗

Genome-wide surveys for phosphorylation-dependent substrates of SCF ubiquitin ligases.

The SCF (Skp1-Cullin-F-box) family of ubiquitin ligases target numerous substrates for ubiquitin-dependent proteolysis, including cell cycle regulators, transcription factors, and signal transducers. Substrates are recruited to an invariant core SCF complex through one of a large family of substrate-specific adapter subunits called F-box proteins, each of which binds multiple specific substrates, often in a phosphorylation-dependent manner. The identification of substrates for SCF complexes has proven difficult, especially given the requirement of often complex phosphorylation events for substrate recognition. The archetype for such interactions is the binding of the yeast F-box protein Cdc4 to its various substrates by means of multiple motifs that weakly match an optimal consensus called the Cdc4 phosphodegron (CPD), which is phosphorylated by cyclin-dependent kinases (CDKs) and possibly other kinases. Provided phosphodegron recognition motifs and/or the targeting kinases for SCF substrates are delineated, it is possible to use genome-wide methods to identify new substrates. Here we describe two methods for the systematic retrieval of SCF substrates based on membrane arrays of synthetic phosphopeptides and on genome-wide kinase substrate profiles. In the first approach, which identifies substrates with strong matches to the CPD, a search of the predicted yeast proteome with the optimal CPD motif identified approximately 1100 matches. A phosphopeptide membrane array corresponding to each of these sequences is then probed with recombinant Cdc4, thereby identifying potential substrates. In the second approach, which identifies substrates that lack strong CPD motifs, a genome-wide set of recombinant CDK substrates is phosphorylated and directly assayed for binding to Cdc4. The proteins corresponding to these hits from each approach can then be subjected to the more stringent criteria of phosphorylation-dependent binding to Cdc4, ubiquitination by SCF(Cdc4)in vitro, and Cdc4-dependent protein instability in vivo. Both methods have identified novel substrates of Cdc4 and may, in principle, be used to identify numerous new substrates of other SCF and SCF-like complexes from yeast to humans.

Amino Acid Sequence↗

Visual performance with multifocal intraocular lenses: mesopic contrast sensitivity under distance and near conditions.

OBJECTIVE: To evaluate distance and near visual performance under bright (photopic) and dim (mesopic) conditions in patients who had undergone uncomplicated cataract extraction with multifocal or monofocal intraocular lens (IOL) implantation. DESIGN: Prospective, nonrandomized, masked, comparative, observational case series. PARTICIPANTS: Thirty-two eyes of 32 patients after zonal-progressive multifocal IOL implantation (Allergan Medical Optics Array SA-40N) and 32 eyes of 32 age-matched patients after monofocal IOL implantation (Allergan Medical Optics SI-40NB). INTERVENTION: All eyes underwent phacoemulsification and IOL implantation. MAIN OUTCOME MEASURES: At 18 months after surgery, the monocular contrast sensitivity (CS) function was measured with sinusoidal grating charts at distance and near, at one photopic luminance level and 2 mesopic luminance levels (85, 5, and 2.5 candelas per square meter). RESULTS: Under bright conditions, CS at distance in the multifocal group was not statistically different (P>0.01) from that in the monofocal group at any tested grating spatial frequency (1.5, 3, 6, 12, and 18 cycles per degree [cpd]). At low luminances, distance CS for the multifocal group was worse than that for the monofocal group at the highest test spatial frequencies (12 and 18 cpd; P<0.01). At near, photopic CS in the multifocal group was lower than at distance; patients with only a monofocal distance correction, however, could not detect the test gratings, even at the highest available contrast. With optimal near spectacle additions (i.e., using the distance correction of the multifocal IOL), there were no significant differences between the photopic near CS values for the multifocal and monofocal groups. When the luminance was decreased, near CS at all spatial frequencies was reduced in both groups. Contrast sensitivity in the near-corrected, multifocal group was significantly worse than in the near-corrected, monofocal group at high spatial frequencies (12 and 18 cpd). CONCLUSIONS: This work supports the findings of earlier authors that the Array multifocal IOL, with its center-distance design, is distance biased. Distance CS is within normal limits under bright photopic conditions but shows deficits at higher spatial frequencies (more than approximately 12 cpd) under dim mesopic conditions. Near CS obtained with the multifocal IOL is below that which can be achieved by an appropriate monofocal near correction, for all spatial frequencies and illumination conditions.

Aged↗

Identification and treatment of depression in a cohort of patients maintained on chronic peritoneal dialysis.

Depression is the most commonly encountered psychological problem in patients with end-stage renal disease (ESRD). Depression has recently been shown to significantly impact on the morbidity and mortality of patients undergoing therapy for ESRD. The present study was designed as a pilot study to evaluate the feasibility of screening a large cohort of patients maintained on chronic peritoneal dialysis (CPD) for depression and then pharmacologically treating those patients assessed to have clinical depression. One hundred thirty-six patients maintained on CPD in our CPD unit were screened for depression using the Beck Depression Inventory (BDI), a self-administered questionnaire. Patients with scores of 11 or greater were referred to a trained psychiatric interviewer for further evaluation to confirm the diagnosis of clinical depression and determine whether the patient was a candidate for antidepressant medication. Sixty-seven patients had BDI scores of 11 or greater, and 60 of these patients were asked to participate in further evaluation and possible therapy. Only 27 patients agreed to further study and were evaluated by a trained psychiatric interviewer for clinical depression. Twenty-three of these patients were assessed to have clinical depression, and 22 patients were eligible for antidepressant medication based on their scores on the Hamilton Depression Scale and psychiatric interview. Eleven patients completed a 12-week course of therapy with antidepressant medication, and their BDI scores decreased from a mean of 17.1 +/- 6.9 (SD) to a mean of 8.6 +/- 3.2. Seven patients were treated with sertraline, 2 patients with bupropion, and 2 patients with nefazodone. It is concluded that (1) depression is commonly present in patients maintained on CPD, (2) the BDI is a useful tool to use to screen for clinical depression, and (3) clinical depression is treatable with medication in this patient population.

Cohort Studies↗

Comparison of different measurements of lean body mass in normal individuals and in chronic peritoneal dialysis patients.

To evaluate different methods of measuring lean body mass (LBM) in chronic peritoneal dialysis (CPD) patients, we first made comparisons in seven normal subjects. Seven methods (total body potassium [TBK] counting, bioelectrical impedance with calculations according to Segal and Deurenberg, near-infrared interactance with and without exercise level included as a variable, anthropometric measurements, and creatinine kinetics) were compared with the standard method of underwater weighing (UW) for measuring LBM. Significant correlations with LBM measured by UW (r > 0.938) were found with LBM measured by all other methods. Compared with UW, the best result in normals was found with TBK as it had high r values, small y-intercepts, and slopes of regression lines close to unity in both measurements of LBM and %LBM; in addition, fat-free mass index by TBK best approximated that by UW and TBK had the lowest mean prediction error with UW. In 11 patients on CPD, LBM was measured by all the above methods except UW. Significant correlations of all methods with LBM measured by TBK used as the reference standard were noted (all r > 0.76) in the CPD population. The LBM measured by creatinine kinetics correlated best (by kilograms or percentage of body weight [%BW]) with LBM from TBK compared with the other methods in which values tended to be higher. The fat-free mass index by creatinine output was nearest to the fat-free mass index by TBK. The root mean square prediction error was lowest between LBM by creatinine output and that by TBK. The findings support the concept of measuring creatinine outputs in CPD patients for estimates of LBM as an index of nutritional status as well as for creatinine clearances as an index of adequacy. Total body potassium and creatinine output measurements of LBM reflect the LBM at normal body fluid volumes ("dry weight") and may be better indices of nutrition in dialysis patients than the other techniques, which include excess fluid in the LBM.

Adult↗

Differing outcomes of gram-positive and gram-negative peritonitis.

Peritonitis remains the leading cause of patient dropout from continuous peritoneal dialysis (CPD) therapy. Few studies have compared patient morbidity, mortality, and outcome for patients undergoing CPD who develop gram-positive and gram-negative peritonitis. We retrospectively reviewed the charts of patients who developed either gram-positive or gram-negative peritonitis between January 1, 1993, and December 31, 1995. Three hundred seventy-five patients who developed 415 episodes of gram-positive and gram-negative peritonitis were maintained on CPD therapy during this time period. There was no difference in age, race, and sex between patients who developed gram-positive or gram-negative peritonitis. More patients with diabetes developed gram-negative peritonitis than gram-positive peritonitis (53% v 40%, respectively; P < 0.05). Coagulase-negative staphylococcal species accounted for 47% of all gram-positive episodes, whereas Klebsiella organisms, Escherichia coli, and Enterobacter organisms accounted for 63% of all gram-negative episodes. Significantly more patients who developed gram-positive peritonitis continued CPD therapy 2 weeks and 6 months after the onset of peritonitis than patients who developed gram-negative peritonitis (97% v 73%; P < 0.05 at 2 weeks and 81% v 58% at 6 months; P < 0.05, respectively). Nine percent of the patients who developed gram-positive peritonitis died within 6 months after the onset of peritonitis, whereas 21% of the patients who developed gram-negative peritonitis died (P < 0.05). Patients who developed gram-negative peritonitis were significantly more likely to require hospitalization than patients who developed gram-positive peritonitis (74% v 24%; P < 0.001). More patients with gram-negative peritonitis required peritoneal catheter removal than patients with gram-positive peritonitis (18% v 4%; P < 0.001). Thirty-two percent of the patients who developed gram-positive peritonitis re-developed an episode of peritonitis with the same organism compared with only 9% of the patients who developed gram-negative peritonitis. Furthermore, peritonitis recurrence with the same organism within 6 months after the initial episode was noted in 60% of the patients with peritonitis caused by Staphylococcus aureus compared with 24% of patients with peritonitis caused by other gram-positive organisms (P < 0.05). We conclude that the outcomes of gram-positive and gram-negative peritonitis are different. When rates of peritonitis are used to predict outcome, it appears that gram-positive and gram-negative peritonitis rates need to be examined separately.

Adult↗

Fibroadenomas: computer-assisted quantitative evaluation of contrast-enhanced power Doppler features and correlation with histopathology.

We aimed to evaluate whether the histopathologic variability of fibroadenomas accounts for their varied appearance in contrast enhanced power Doppler (PD). Forty patients with fibroadenomas (aged 19 to 61 years) underwent power Doppler ultrasound (US) prior to and following IV bolus injection of a microbubble contrast agent. A 3-min computer-assisted assessment of the color pixel density (CPD) was used for objective evaluation of the increase in color Doppler signals. Enhancement characteristics were correlated to histopathologic features of microvessel density and epithelial hyperplasia, patient's age, tumor size, use of exogenous hormones and menopausal status. Epithelial hyperplasia was diagnosed in 19 patients. Compared to baseline values, patients with epithelial hyperplasia showed a significant increase in mean CPD following contrast media administration (p < 0.01). There was a significant correlation to patient's age (p < 0.0001) and tumor size (p < 0.0001), but not to the use of exogenous hormones and menopausal status. Microvessel counts did not show a significant correlation to CPD at baseline (p = 0.07) or with CPD on contrast enhanced PD (p = 0.13), or with patient age (p = 0.43) or tumor size (p = 0.34). Intratumoral epithelial hyperplasia, primarily occurring in young patients, may contribute to the differential diagnostic overlap in some fibroadenomas and thus limit the ability of PD to distinguish between benign and malignant masses on the basis of enhancement characteristics.

Adult↗

Estimation of antithyroid drug dose in Graves' disease: value of quantification of thyroid blood flow with color duplex sonography.

The purpose of this study was to evaluate if there is an association between the antithyroid drug dose that is needed to establish euthyroidism and thyroid blood flow measurements. A total of 23 Graves' disease patients with euthyroidism taking antithyroid drug therapy were enlisted to undergo spectral duplex sonography of the thyroid arteries and color-flow mapping of the thyroid gland. Color pixel density (CPD) was calculated with computer assistance from the color-flow maps. There was a strong correlation between the CPD and methimazole dose (rp = 0.79). Methimazole maintenance dosage could be predicted from CPD values with a coefficient of determination of 0.62. In conclusion, CPD measurements could be a useful tool for the clinical endocrinologist to estimate the antithyroid drug dose that is needed to maintain euthyroidism.

Adult↗

p53-degradation by HPV-16 E6 preferentially affects the removal of cyclobutane pyrimidine dimers from non-transcribed strand and sensitizes mammary epithelial cells to UV-irradiation.

Nucleotide excision repair (NER), the most versatile and ubiquitous mechanism for DNA repair, operates to remove many types of DNA base lesions. We have studied the role of p53 function in modulating the repair of DNA damage following UV irradiation in normal and p53-compromised human mammary epithelial cells (HMEC). The effect of UV-induced DNA damage on cellular cytotoxicity and apoptosis was determined in conjunction with global, gene- and strand-specific repair. Cytotoxicity studies, using clonogenic survival and MTT assays, showed that HPV-16 E6-expressing HMEC were more UV sensitive than p53-WT cell lines. High apoptotic index obtained with p53-compromised cells was in conformity to both the low clonogenic survival and the low cellular viability. No discernible differences in the formation of initial UV-induced cyclobutane pyrimidine dimers (CPD) were observed in the cell lines of varying p53 functional status. However, the extent and the rate of damage removal from genome overall were highest for p53-WT cells. Further examination of strand-specific repair in the p53 gene revealed that the removal of CPD in the non-transcribed strand (NTS) was slower in p53-compromised cells compared to the normal p53-WT cell lines. These results suggest that loss of p53 function, in the absence of other genetic alterations, decreased both overall amount of CPD repaired and their removal rate from the genome. Additionally, normal function of p53 is required for the repair of the NTS, but not of the transcribed strand (TS) in genomic DNA in human epithelial cells. Thus, failure of quantitative removal of CPD by global genomic repair (GGR), due to loss of p53 function, causes the enhanced UV sensitivity and increased damage-induced apoptosis via a p53-independent pathway. Nevertheless, recovery of cells from UV damage requires normal p53 function and efficient GGR.

Apoptosis↗

Provision of dietetic care in children on chronic peritoneal dialysis.

OBJECTIVE: To estimate the provision of dietetic care necessary to manage and support children receiving chronic peritoneal dialysis (CPD) with/without nutritional support via a gastrostomy button (GB) and their families. DESIGN: Three-year prospective, longitudinal study documenting dietetic contacts (direct: inpatient/outpatient, telephone, home, school, and family practitioner visits; and indirect: with other health professionals). SETTING: Regional Pediatric Renal Unit. PARTICIPANTS: Thirteen children (7 male; 5 <5 yrs of age) commenced CPD at a mean age of 7.7 years (range, 0.2 to 8.5 years). Eight children received tube feeding (7 GB, 1 nasogastric [NG]) in combination with CPD at a mean age of 4.3 years (range, 0.2 to 8.2 years). MAIN OUTCOME MEASURES: Quantitative data regarding dietetic contacts and growth parameters. RESULTS: Seven hundred eighty-one dietetic contacts were recorded during 182 patient months of observation, with a mean of 5.9 (standard deviation [SD] 1.9) contacts per patient, per month in children <5 years of age, compared with 3.1 (SD 1.6) contacts in children >5 years of age. Eighty-two percent of contacts were with children receiving nutritional support via a GB. Telephone contact accounted for 41% of all contacts in the less than 5 years of age group, compared with 7% in children greater than 5 years of age. Mean standard deviation scores (SDS) for height and weight at the start of the study were -1.2 and -1.32, and at the end were -1.14 and -0. 73. Body mass index (BMI) SDS significantly improved from -0.91 to 0. 17 (P = 0.03). CONCLUSION: This study illustrates the number and nature of dietetic contacts that we felt were required to support children and families on CPD. Attempts to achieve adequate nutritional intakes for growth require frequent adjustments of nutritional prescriptions, particularly in preschool children.

Adolescent↗