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PubMed2026

Latent profile analysis of pregnant exercise adherence and the relationship with demographic and socio-psychological factors: a multicentre cross-sectional study.

BACKGROUND: Pregnancy physical activity (PA) and exercise benefits both mothers and babies, but requires sustained adherence. Many pregnant women fail to meet recommended levels. The reasons for low adherence comprised fluctuating physiological and environmental factors. This study aims to identify discrete profiles of pregnant women based on exercise adherence and to examine differences in demographic and socio-psychological factors across these profiles. METHODS: A survey was conducted among 1,255 pregnant women in three hospitals in Shenzhen, Dongguan, and Shunde, China, using the Exercise Adherence Rating Scale (EARS), the Pregnancy Exercise Self-Efficacy Scale (P-ESES), and the Pregnancy Physical Activity Social Support Scale (P-PASSS). In the analysis, EARS items were scored higher, indicating a healthier state (e.g., sufficient time and energy). Latent profile analysis (LPA) was employed to classify adherence profiles, and multinomial logistic regression was used to examine differences in demographic, self-efficacy, and social support across four groups. RESULTS: Four profiles of exercise adherence were identified: (1) Profile 1 (16.97%), characterized by deficits in time and energy, (2) Profile 2 (15.22%), a group with sufficient time resources but the lowest self-efficacy, (3) Profile 3 (43.98%), characterized by high adherence despite moderate barriers, and (4) Profile 4 (23.83%), a group with optimal exercise adherence, confidence, and resources. Women with higher P-ESES (OR: 1.14-1.38) and P-PASSS (OR: 1.04-1.06) scores were more likely to be in Profiles 3 and 4. Additionally, women's partners who never or occasionally exercise were significantly more likely to be categorized into Profile 1 (OR = 0.18 for Profile 4 vs. Profile 1). Furthermore, the first trimester emerged as a significant risk period for lower exercise adherence, whereas overweight/obesity was independently associated with higher odds of membership in Profile 4. CONCLUSION: The study identified four distinct profiles of exercise adherence among pregnant women. 32.19% of participants were in the two lower exercise-adherence groups. Pregnant women in Profile 1 were characterized by challenges related to a lack of time and knowledge. Participants in Profile 2 showed the lowest exercise self-efficacy and social support among the four profiles. Furthermore, women in early pregnancy were more likely to have lower adherence profiles. Hence, targeted interventions addressing these specific groups are warranted to improve exercise adherence during pregnancy.

Humans↗
PubMed1981

The fine structure of the submucous plexus of the guinea-pig ileum. II. Description and analysis of vesiculated nerve profiles.

A fine structural study has been made of the vesiculated nerve profiles of the submucous plexus of both normally innervated and extrinsically denervated segments of guinea-pig ileum. Two types of nerve profiles could be readily distinguished by their vesicular content after conventional fixation. The first type, comprising 5% of all intrinsic profiles, consisted of predominantly small vesicles containing electron dense material which usually formed a ring around the inner face of the vesicular membrane but sometimes partially or completely filled the vesicle. These profiles, termed ring-vesicle-containing profiles, remained after extrinsic denervation, and their vesicular content did not change following injection of reserpine or 5-hydroxydopamine. Thus ring-vesicle-containing profiles are not adrenergic. Profiles which were positive for the uranaffin method were similar in morphology and frequency of occurrence to ring-vesicle-containing profiles, although it is not possible to say that they are the same. The second type of profile, comprising 95% of all intrinsic profiles, contained varying proportions of large granular and small clear vesicles. These heterogeneous profiles were present in both normally innervated and extrinsically denervated tissue. Their vesicular content did not change following injection of reserpine, however, some profiles of this type in normally innervated, but not in extrinsically denervated, intestine contained electron dense deposits after injection of 5-hydroxydopamine. This means that noradrenergic profiles are a subpopulation of the heterogeneous profiles in normally innervated tissue. Analysis of intrinsic heterogeneous profiles showed that the proportion and packing density of large granular vesicles formed continuous distributions which did not provide any basis for further subdivision of this type of profile. Ring-vesicle-containing and heterogeneous profiles often formed synapses with neuronal cell bodies and processes. Two rarer types of profiles were also seen. The first type contained mainly small flattened vesicles which took up 5-hydroxydopamine and was not present in extrinsically denervated tissue. This type, like the group described above, is considered to be noradrenergic. The second rare type contained large numbers of lysosome-like dense bodies and vesicles of different sizes and content and was seen in both normally innervated and denervated tissue. This type probably represents spontaneously degenerating nerve profiles.

Animals↗
PubMed2002

Subgingival microbial profiles in refractory periodontal disease.

BACKGROUND/AIM: The purpose of the present investigation was to examine subgingival microbial profiles associated with refractory periodontitis and to seek such profiles in periodontally healthy, periodontally well-maintained elder and untreated periodontitis subjects. METHODS: 36 subjects were defined as refractory on the basis of further attachment loss after scaling and root planing, surgery and systemically administered antibiotics. A total of 890 subgingival plaque samples (mean/subject=24.7) were taken from the mesial aspect of each tooth in each subject at baseline and individually processed for their content of 40 subgingival taxa using checkerboard DNA-DNA hybridization. Cluster analysis was performed on mean within subject species counts using the chord coefficient and an average unweighted linkage sort. Significant differences among clusters for individual and complexes of species were sought using the Kruskal Wallis test. The microbial profiles of the refractory subjects were compared with those of 27 periodontally healthy subjects (n plaque samples=708), 35 periodontally well-maintained elder subjects (n plaque samples=801) and 115 untreated adult periodontitis subjects (n plaque samples=2871). RESULTS: 28 of 36 refractory subjects fell into 4 clusters with >29% similarity. 10 of 40 species and 4 of 7 complexes differed significantly among clusters. Profile (Cluster) I (n=4) was characterized by high proportions of "yellow" and "green" complex species, profile II (n=3) by low total counts and high proportions of "orange" and "purple" complex species, profile III (n=9) by high total counts and counts of Actinomyces and "purple" complex species, profile IV (n=12) by high proportions of "red" and "orange" complex species. The mean profiles of each cluster were subjected to cluster analysis with microbial data from 4380 (mean 24.7) baseline subgingival plaque samples from 27 periodontally healthy, 35 treated, well-maintained elders and 115 untreated adult periodontitis subjects. 12 clusters were formed with >41% similarity. 3 of the refractory profiles were detected in 3 cluster groups. Profile II in a cluster of 1 healthy, 1 elder and 4 untreated periodontitis subjects; profile III in a cluster of 1 healthy, 2 elder and 12 periodontitis subjects; Profile IV, with 1 healthy and 5 untreated periodontitis subjects. The profile not detected in non refractory subjects was dominated by Streptococcus species. 9 clusters did not harbor refractory profiles. 11.1% of healthy, 8.6% of elder and 18.3% of periodontitis subjects were in clusters exhibiting refractory microbial profiles. CONCLUSIONS: 4 subgingival microbial profiles were detected among refractory subjects. "Refractory microbial profiles" could be detected in subjects who had not yet exhibited refractory disease.

Actinobacillus↗
PubMed2002

Performance profiles: the influence of patient satisfaction data on physicians' practice.

OBJECTIVE: Health maintenance organizations and other payers increasingly use patient satisfaction data to profile physician performance. Little is known about physicians' use of patient satisfaction information or how profiles affect individual physician behaviors. The objective of this study was to examine primary care physicians' perceptions of performance profiles based on patient satisfaction data, whether physicians use profiles to change practice behaviors, and which profile components physicians think are important for assessing quality of care. METHODS: A written survey was conducted in 1998 in Massachusetts with 810 primary care physicians (304 pediatricians, 201 family practitioners, 305 internists) who had at least 100 patients in a large managed care plan and had received 1 or more profiles based on patient satisfaction data. Physicians in training were excluded. Physicians' perceptions of profiles and their reported use to change practice behaviors were measured. RESULTS: The response rate was 68%. Twenty-three percent reported that profiles were very or extremely useful for improving care. Only 7% reported using profiles often or always to change care. Although specific profile components related to interpersonal aspects of care were rated more useful, <11% reported using profiles often or always to make changes on any individual component. A majority, 67% to 89%, reported making no or minor changes on profile components. Responses did not vary by specialty, demographics, or practice characteristics. Physicians rated interpersonal factors (eg, ability to communicate with patients, ability to show caring and empathy) as the most important indicators of quality of care; they report having the most control over these factors. Office factors (eg, staying on schedule, ease of scheduling appointments) were ranked as least important for assessing quality of care. CONCLUSION: Although health maintenance organizations and other payers increasingly use patient satisfaction reports to profile individual physicians and guide physician compensation and health plan participation, <25% of primary care physicians find profiles useful for improving patient care and even fewer report using profiles to change practice. Profiles likely have limited influence on behavior changes. Payers who invest in profiles may find it advantageous to focus on health plans and practice facilities rather than on individual physicians.

Attitude of Health Personnel↗
PubMed2006

Comparative assessment of performance and genome dependence among phylogenetic profiling methods.

BACKGROUND: The rapidly increasing speed with which genome sequence data can be generated will be accompanied by an exponential increase in the number of sequenced eukaryotes. With the increasing number of sequenced eukaryotic genomes comes a need for bioinformatic techniques to aid in functional annotation. Ideally, genome context based techniques such as proximity, fusion, and phylogenetic profiling, which have been so successful in prokaryotes, could be utilized in eukaryotes. Here we explore the application of phylogenetic profiling, a method that exploits the evolutionary co-occurrence of genes in the assignment of functional linkages, to eukaryotic genomes. RESULTS: In order to evaluate the performance of phylogenetic profiling in eukaryotes, we assessed the relative performance of commonly used profile construction techniques and genome compositions in predicting functional linkages in both prokaryotic and eukaryotic organisms. When predicting linkages in E. coli with a prokaryotic profile, the use of continuous values constructed from transformed BLAST bit-scores performed better than profiles composed of discretized E-values; the use of discretized E-values resulted in more accurate linkages when using S. cerevisiae as the query organism. Extending this analysis by incorporating several eukaryotic genomes in profiles containing a majority of prokaryotes resulted in similar overall accuracy, but with a surprising reduction in pathway diversity among the most significant linkages. Furthermore, the application of phylogenetic profiling using profiles composed of only eukaryotes resulted in the loss of the strong correlation between common KEGG pathway membership and profile similarity score. Profile construction methods, orthology definitions, ontology and domain complexity were explored as possible sources of the poor performance of eukaryotic profiles, but with no improvement in results. CONCLUSION: Given the current set of completely sequenced eukaryotic organisms, phylogenetic profiling using profiles generated from any of the commonly used techniques was found to yield extremely poor results. These findings imply genome-specific requirements for constructing functionally relevant phylogenetic profiles, and suggest that differences in the evolutionary history between different kingdoms might generally limit the usefulness of phylogenetic profiling in eukaryotes.

Bacterial Proteins↗
PubMed1998

[Plasmid profile typing of Salmonella typhimurium and its distribution in some provinces and cities of China].

OBJECTIVE: To study the relationship between the infection and prevalence of Salmonella typhimurium. METHODS: From 1980 to 1995, when Salmonella typhimurium infection was prevalent in north and south China, a total of 2,655 isolates of Salmonella typhimurium were collected from 19 provinces, municipalities, and autonomous regions and Hong Kong Special Administrative Region for plasmid profile analysis. The profiles consisting of some small plamids were recorded with capital letters A to J, and the profile which was free from small plasmid was recorded with capital letter O. Large plasmid in molecular weights of 140-20 Mdal showing in profiles was recorded with Arabic numerals 9 to 0 respectively. Having two or more than two large plasmids, the profile was recorded with two or more Arabic numerals. RESULTS: The 2,655 strains were divided into 11 plasmid profile groups and 168 plasmid profile types. Of 52 plasmid profile types frequently isolated, plasmid profile type O 4 was distributed extensively in 16 provinces, municipalities, and autonomous rehions and Hong Kong. Plasmid profile type O 5 was isolated in 5 provinces and Hong Kong, mostly in Jiangxi and Hubei. Plasmid profile type J 4 was isolated in 7 provinces, municipalities and autonomous regions, mostly in Jiangxi. Five plasmid profile types of Group A caused a big prevalence of nosocomial infection in Henan. Type A 6 was also isolated in Xinjiang and Anhui. Six plasmid profile types of Group E were prevalent in Xinjiang predominantely, three types caused nosocomial infection in Shanghai, type E 82 caused nosocomial infection and food poisoning in Liaoning. Type F 4 was isolated in 4 provinces, mostly in jiangxi and Fujian. Many plasmid profile types were prevalent local. Types B 5, BCEG 60, BE 6, B' 0 G 6, G 5 and EG 6 were prevalent in Jiangxi, Types IF'4, IF'H40 and F 9864 were prevalent in Sandong, Type IF'4 was also isolated in Jiangsu and Hubei, Type IF 40 in Anhui, Type BH 6 in Huibei, and Type EH 5 in Fujian. CONCLUSION: Plasmid profile analysis showed the same types in the prevance but different plasmid profiles in different provinces.

China↗
PubMed1992

Inaccuracies in manufacturer-reported deflated PTCA balloon profiles.

Deflated balloon profile is an important consideration in the selection of PTCA catheters. In order to test the accuracy of manufacturer-reported balloon profiles, we measured deflated shoulder and mid-balloon profile in 107 unused catheters (2.0, 2.5, and 3.0 mm) from 6 manufacturers using a precision hole gauge with a resolution of .001 inches. A significant difference was defined as a discrepancy greater than or equal to 0.003 inches from the manufacturer's reported profile. During Phase I, measurements were obtained at room temperature on catheters directly out of the package. Of the 36 models tested, 21/36 (56%) had measured shoulder profiles that were larger than their reported profile, and 29/36 (81%) had mid-balloon profiles that were larger than their reported profile. During Phase II, measurements were made at body temperature following a 60 second inflation at 120 psi (8.16 atm). Of 33 models tested, 18/33 (55%) had measured shoulder profiles that were larger than their reported profile; 26/33 (79%) had mid-balloon profiles that were larger than their reported profile. The term "profile" is imprecisely defined. Manufacturer-reported deflated PTCA balloon profiles are not always accurate. Independent and uniform testing of balloon profiles is necessary for valid comparisons between balloons and manufacturers.

Angioplasty, Balloon, Coronary↗
PubMed2005

A comparative assessment of the perception of Chinese facial profile esthetics.

INTRODUCTION: The aim of this study was to compare the perception of male and female Chinese facial profile esthetics between dental professionals, dental students, and laypersons. MATERIAL: The sample comprised 31 dental professionals (20 orthodontists, 11 oral surgeons), 92 dental students, and 152 laypersons in an Asian community. The facial profile photographs and lateral cephalometric radiographs of a Chinese man and a woman, each with a normal profile, a Class I incisor relationship, and a Class I skeletal pattern, were digitized. The digital images were modified to obtain 7 facial profiles for each sex. The images were constructed by altering cephalometric skeletal and dental hard tissue Chinese normative values by 2 standard deviations in the anteroposterior plane only. The 7 profiles were (1) bimaxillary protrusion, (2) protrusive mandible, (3) retrusive mandible, (4) normal profile (Class I incisor with Class I skeletal pattern), (5) retrusive maxilla, (6) protrusive maxilla, and (7) bimaxillary retrusion. RESULTS: Normal and bimaxillary retrusion Chinese male and female profiles were perceived to be highly attractive by all 3 groups. Profiles with a protrusive mandible were perceived to be the least attractive. Dental professionals, dental students, and laypersons were highly correlated for the perception of male (r > 0.67) and female (r > 0.93) profile esthetics. All correlation coefficients were found to be significant for the perception of female profiles, but, for male profiles, only the correlation coefficient between dental students and laypersons was significant. CONCLUSIONS: Chinese male and female profiles that were normal or had bimaxillary retrusion were perceived to be highly attractive by dental professionals, dental students, and laypersons, and profiles with a protrusive mandible were perceived to be the least attractive. Dental students and laypersons were more tolerant of a male profile with a retrusive mandible than were dental professionals, and all groups were more tolerant of bimaxillary protrusion in women than in men. Dental professionals, dental students, and laypersons had a similar trend in male and female esthetic preferences. The perception of female profiles by all 3 groups was highly and significantly correlated. Only the perception of male esthetics by dental students and laypersons was not significantly correlated with dental professionals.

Adult↗
PubMed2006

Experimental determination of the effect of detector size on profile measurements in narrow photon beams.

The aim of this work is to investigate experimentally the detector size effect on narrow beam profile measurements. Polymer gel and magnetic resonance imaging dosimetry was used for this purpose. Profile measurements (Pm(s)) of a 5 mm diameter 6 MV stereotactic beam were performed using polymer gels. Eight measurements of the profile of this narrow beam were performed using correspondingly eight different detector sizes. This was achieved using high spatial resolution (0.25 mm) two-dimensional measurements and eight different signal integration volumes A X A X slice thickness, simulating detectors of different size. "A" ranged from 0.25 to 7.5 mm, representing the detector size. The gel-derived profiles exhibited increased penumbra width with increasing detector size, for sizes >0.5 mm. By extrapolating the gel-derived profiles to zero detector size, the true profile (Pt) of the studied beam was derived. The same polymer gel data were also used to simulate a small-volume ion chamber profile measurement of the same beam, in terms of volume averaging. The comparison between these results and actual corresponding small-volume chamber profile measurements performed in this study, reveal that the penumbra broadening caused by both volume averaging and electron transport alterations (present in actual ion chamber profile measurements) is a lot more intense than that resulted by volume averaging effects alone (present in gel-derived profiles simulating ion chamber profile measurements). Therefore, not only the detector size, but also its composition and tissue equivalency is proved to be an important factor for correct narrow beam profile measurements. Additionally, the convolution kernels related to each detector size and to the air ion chamber were calculated using the corresponding profile measurements (Pm(s)), the gel-derived true profile (Pt), and convolution theory. The response kernels of any desired detector can be derived, allowing the elimination of the errors associated with narrow beam profile measurements.

Fourier Analysis↗
PubMedDate not supplied

No prognostic significance of antimitochondrial antibody profile testing in primary biliary cirrhosis.

BACKGROUND/AIMS: The rate of disease progression varies considerably between individuals with primary biliary cirrhosis (PBC). On the basis of serological subtyping 4 antimitochondrial antibody (AMA) profiles (A, B, C and D) can be defined. The finding of previous studies that profile C/D is associated with a progressive course, in contrast to profile A/B, is a question of debate. The aim of the study was to investigate whether AMA profiles predicted the course for a cohort of Dutch PBC patients. METHODOLOGY: Patients with an established diagnosis of AMA-positive PBC, AMA-negative PBC patients, non-PBC decompensated cirrhotics and healthy volunteers. Serum samples from 38 AMA-positive progressive patients, 31 AMA-positive patients without evidence of progression for at least 6 years, 5 AMA-negative PBC patients, 5 non-PBC decompensated cirrhotics and 5 healthy volunteers were assessed. AMA profiles were determined without knowledge of the clinical data. RESULTS: In the progressive AMA-positive group, 13% had profile A/B and 84% had profile C/D. In the non-progressive group, 13% had profile A/B, 77% profile C/D; 10% had no profile. During follow-up, a change from profile A/B to profile C/D or vice versa was not observed. CONCLUSIONS: This study found that not only PBC patients with AMA profile C/D but also patients with profile A/B may run a progressive course and therefore does not support the suggestion that AMA profiles can be used as independent prognostic indicator. The divergent results of this and previous studies may be explained by the selection of different patient populations.

Adult↗
PubMed2004

A comparison of scoring functions for protein sequence profile alignment.

MOTIVATION: In recent years, several methods have been proposed for aligning two protein sequence profiles, with reported improvements in alignment accuracy and homolog discrimination versus sequence-sequence methods (e.g. BLAST) and profile-sequence methods (e.g. PSI-BLAST). Profile-profile alignment is also the iterated step in progressive multiple sequence alignment algorithms such as CLUSTALW. However, little is known about the relative performance of different profile-profile scoring functions. In this work, we evaluate the alignment accuracy of 23 different profile-profile scoring functions by comparing alignments of 488 pairs of sequences with identity < or =30% against structural alignments. We optimize parameters for all scoring functions on the same training set and use profiles of alignments from both PSI-BLAST and SAM-T99. Structural alignments are constructed from a consensus between the FSSP database and CE structural aligner. We compare the results with sequence-sequence and sequence-profile methods, including BLAST and PSI-BLAST. RESULTS: We find that profile-profile alignment gives an average improvement over our test set of typically 2-3% over profile-sequence alignment and approximately 40% over sequence-sequence alignment. No statistically significant difference is seen in the relative performance of most of the scoring functions tested. Significantly better results are obtained with profiles constructed from SAM-T99 alignments than from PSI-BLAST alignments. AVAILABILITY: Source code, reference alignments and more detailed results are freely available at http://phylogenomics.berkeley.edu/profilealignment/

Algorithms↗
PubMed1984

Soft-tissue profile preference.

The relative influence on profile preference of the anteroposterior maxillomandibular relation, the lower facial height, and the form of the dorsum of the nose is a source of interesting controversy. In order to obtain more information on this subject, twenty-seven shadow profile photographs were artificially constructed to represent the main characteristics of the nine profile types proposed by Sassouni combined with three different kinds of nose dorsum. Each series of nine profiles was ranked according to the personal esthetic preference of 249 adults (mean age, 23 years). One group of test persons (40 females and 91 males) had no orthodontic background, while another group (49 females and 69 males) had received some orthodontic teaching. Chi-square tests of significance showed no significant difference between male and female participants in esthetic preference for the sex of a profile. Also, the difference in orthodontic knowledge had no significant effect on esthetic preference. Nose dorsum changes induced significant differences only in Class II normal profiles; convex noses were less appreciated. Calculation of average preference values revealed that Class I normal profile types were clearly the favored ones, followed by Class I deep profiles. Open profile types, on the contrary, were obviously the least appreciated. This sequence indicates that, in profile evaluations, vertical profile characteristics could be more important than anteroposterior features and that a lengthening of the soft-tissue profile is not desirable in most cases. Seven weeks after the first ranking of male profiles, 193 persons were retested. The rank correlation values according to Kendall showed that one out of four persons ranked profiles significantly different in the retest.

Adult↗
PubMed2003

On the role of structural information in remote homology detection and sequence alignment: new methods using hybrid sequence profiles.

Structural alignments often reveal relationships between proteins that cannot be detected using sequence alignment alone. However, profile search methods based entirely on structural alignments alone have not been found to be effective in finding remote homologs. Here, we explore the role of structural information in remote homolog detection and sequence alignment. To this end, we develop a series of hybrid multidimensional alignment profiles that combine sequence, secondary and tertiary structure information into hybrid profiles. Sequence-based profiles are profiles whose position-specific scoring matrix is derived from sequence alignment alone; structure-based profiles are those derived from multiple structure alignments. We compare pure sequence-based profiles to pure structure-based profiles, as well as to hybrid profiles that use combined sequence-and-structure-based profiles, where sequence-based profiles are used in loop/motif regions and structural information is used in core structural regions. All of the hybrid methods offer significant improvement over simple profile-to-profile alignment. We demonstrate that both sequence-based and structure-based profiles contribute to remote homology detection and alignment accuracy, and that each contains some unique information. We discuss the implications of these results for further improvements in amino acid sequence and structural analysis.

Amino Acid Sequence↗
PubMed2000

Variation of relative transit dose profiles with patient-detector distance.

BACKGROUND AND PURPOSE: In view of using portal images for exit dosimetry, an experimental study is performed of relative transit dose profiles at different distances behind patients (and phantoms) and of their relation to the exit dose profile. MATERIALS AND METHODS: Irregular, homogeneous polystyrene phantoms with a variable thickness to simulate head and neck (H&N) treatments (6-MV photon beam) are investigated by ionization chamber measurements performed close to the exit surface and at various distances behind the phantom (10, 20 and 30 cm). Similar measurements are performed for a rectangular phantom with large inhomogeneities (A1 and air). For one irregular homogeneous phantom and an irregular phantom containing an A1 inhomogeneity, ionization chamber measurements are performed at the exit surface, and a portal film image is taken at 30 cm behind the phantom. Portal films of a patient treated for a head and neck malignancy are evaluated for different air gaps behind the patient. RESULTS: For the irregular phantoms, deviations up to 15% and more are observed between the exit dose profile (along the shaped surface of the phantom) and the transit profile close to the phantom (perpendicular to the beam axis). There is, however, a good agreement--within 3%--between the exit profile and the transit profile at 30 cm. For the rectangular, inhomogeneous phantom, the deviation between the exit profile and the transit dose profile at 30 cm does not exceed 5%; transit dose profiles overestimate the exit dose for the air cavity and underestimate the dose for the A1 inhomogeneity. Measurements on portal films of a H&N patient for different air gaps confirm the order of magnitude of the difference observed between transit dose profiles close to the patient and transit dose profiles at some distance behind the patient. CONCLUSIONS: For 6-MV photon beam treatments with significant thickness variations (H&N), large variations (> 10%) are observed in transit dose profiles as a function of the air gap between the patient and the portal film. For this energy, a good agreement is found between the exit profile and the transit profile at about 30 cm behind the patient.

Head and Neck Neoplasms↗
PubMed2003

Clinical assessment identifies hemodynamic profiles that predict outcomes in patients admitted with heart failure.

OBJECTIVES: This study was designed to determine the relevance of a proposed classification for advanced heart failure (HF). Profiles based on clinical assessment of congestion and perfusion at the time of hospitalization were compared with subsequent outcomes. BACKGROUND: Optimal design of therapy and trials for advanced HF remains limited by the lack of simple clinical profiles to characterize patients. METHODS: Prospective analysis was performed for 452 patients admitted to the cardiomyopathy service at the Brigham and Women's Hospital with a diagnosis of HF. Patients were classified by clinical assessment into four profiles: profile A, patients with no evidence of congestion or hypoperfusion (dry-warm, n = 123); profile B, congestion with adequate perfusion (wet-warm, n = 222); profile C, congestion and hypoperfusion (wet-cold, n = 91); and profile L, hypoperfusion without congestion (dry-cold, n = 16). Other standard predictors of outcome were included and patients were followed for the end points of death (n = 117) and death or urgent transplantation (n = 137) at one year. RESULTS: Survival analysis showed that clinical profiles predict outcomes in HF. Profiles B and C increase the risk of death plus urgent transplantation by univariate (hazard ratio [HR] 1.83, p = 0.02) and multivariate analyses (HR 2.48, p = 0.003). Moreover, clinical profiles add prognostic information even when limited to patients with New York Heart Association (NYHA) class III/IV symptoms (profile B: HR 2.23, p = 0.026; profile C: HR 2.73, p = 0.009). CONCLUSIONS: Simple clinical assessment can be used to define profiles in patients admitted with HF. These profiles predict outcomes and may be used to guide therapy and identify populations for future investigation.

Blood Pressure↗
PubMed1991

Association of the renin-sodium profile with the risk of myocardial infarction in patients with hypertension.

BACKGROUND: To test the prognostic value of plasma renin activity prospectively, we determined the pretreatment renin-sodium profile of 1717 subjects with mild-to-moderate hypertension (mean age, 53 years; 36 percent white; 67 percent men) in a systematic work-site treatment program. METHODS: Renin profiles, obtained by plotting plasma renin activity against the urinary excretion of sodium, were classified as high (12 percent of the subjects), normal (56 percent), and low (32 percent), and there were expected variations according to age, sex, and race. Modified stepped-care treatment for hypertension, prescribed without reference to the renin profile, was similar in the three renin groups. RESULTS: Mean (+/- SD) blood pressure at entry was 151 +/- 19/100 +/- 10 mm Hg in the subjects with a high renin profile, 151 +/- 19/97 +/- 10 mm Hg in those with a normal profile, and 151 +/- 20/96 +/- 11 mm Hg in those with a low profile. During 8.3 years of follow-up, there were 27 myocardial infarctions. As adjusted for age, sex, and race, the incidence of myocardial infarction per 1000 person-years was 14.7 among the subjects with a high renin profile, 5.6 among those with a normal profile, and 2.8 among those with a low profile (rate ratio for high vs. low, 5.3; 95 percent confidence interval, 3.4 to 8.3). The rate of mortality from all causes was 9.3 in the high-profile group, 5.3 in the normal-profile group, and 3.9 in the low-profile group. The independent association of a high renin profile with myocardial infarction (but not with stroke or noncardiovascular events) was affirmed by Cox analyses (rate ratio for high vs. normal plus low, 3.2; 95 percent confidence interval, 1.2 to 8.4) after adjustment for race, sex, age at entry, serum cholesterol level, smoking status, electrocardiographic evidence of left ventricular hypertrophy, blood glucose level, body-mass index, history of cardiovascular disease or treatment, blood pressure, and use of beta-blockers. CONCLUSIONS: In the study population, whose blood pressure before and during treatment was in a narrow range, and after other cardiovascular risk factors had been considered, the renin profile before treatment remained independently associated with the subsequent risk of myocardial infarction.

Blood Pressure↗
PubMed2000

Opinions on provider profiling: telephone survey of stakeholders.

The views of producers, purchasers, and users of provider profiling concerning this practice were studied. A snowball sample of individuals representing seven groups with a stake in retrospective provider profiling were interviewed by telephone over a 12-week period in 1997. Participants were asked what they believed were the most important uses for profiles, who should receive copies of profiles, and what the limitations of profiles are. A semi-structured format was used to ensure that each interview was comparable and complete. The responses were aggregated, and qualitative research approaches were used to analyze them. A total of 40 people were interviewed. A majority of the respondents cited physician education, changing physician behavior, and monitoring and improving the quality of care as valid uses of provider profiles. A majority believed that the recipients of profile data should include the individual providers being profiled, medical administrative staff, people directly involved in the profiling program, pharmacists, and health plan administrators. The respondents acknowledged many limitations of profiles, with the top concern being inherent problems in the use of billing and administrative databases for profiling. Interviews with stakeholders in provider profiling yielded insights into the strengths and weaknesses of profiling, as well as echoing findings reported elsewhere. Health system administrators and health care professionals need to be aware of these issues as they use and modify profiling.

Drug Utilization Review↗
PubMed2002

Antimitochondrial antibody profiles: are they valid prognostic indicators in primary biliary cirrhosis?

OBJECTIVE: Retrospective studies have reported that subtypes of antimitochondrial antibodies (AMAs) discriminate between a benign and a progressive course in patients with primary biliary cirrhosis (PBC). Four AMA profiles (A-D) were defined: profiles A and B associated with a benign course and C and D with a progressive course. We aimed to confirm whether AMA profiles predict prognosis in a large sample of North American patients with PBC. METHODS: Stored pretreatment sera from patients with PBC from two centers were tested for AMA profiles using standard techniques. Proportions of patients in each profile group reaching the endpoints of liver transplantation or death from liver disease were compared. Kaplan-Meier curves were constructed comparing AMA profiles. RESULTS: All 472 patients studied had AMA positive, biopsy-confirmed PBC. Mean age at diagnosis was 53 yr, 90% were female, mean follow-up was 7.6 yr (range = 0.5-23), and 51% received ursodeoxycholic acid for >6 months. Profile A was not detected; 16.7% had profile B; 51.1%, profile C; and 32.2%, profile D. Duration of follow-up was comparable among the different profile groups. The proportions of patients reaching endpoints of death from liver disease or transplantation did not differ among the AMA profiles. No difference in the Kaplan-Meier curves between the different profile groups was observed (p > 0.05). CONCLUSION: AMA profiles do not predict prognosis in patients with PBC.

Autoantibodies↗