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At least 127 records · Page 7Linked to original sources
PubMed2004

Visual perception in Parkinson disease dementia and dementia with Lewy bodies.

OBJECTIVE: To quantify visual discrimination, space-motion, and object-form perception in patients with Parkinson disease dementia (PDD), dementia with Lewy bodies (DLB), and Alzheimer disease (AD). METHODS: The authors used a cross-sectional study to compare three demented groups matched for overall dementia severity (PDD: n = 24; DLB: n = 20; AD: n = 23) and two age-, sex-, and education-matched control groups (PD: n = 24, normal controls [NC]: n = 25). RESULTS: Visual perception was globally more impaired in PDD than in nondemented controls (NC, PD), but was not different from DLB. Compared to AD, PDD patients tended to perform worse in all perceptual scores. Visual perception of patients with PDD/DLB and visual hallucinations was significantly worse than in patients without hallucinations. CONCLUSIONS: Parkinson disease dementia (PDD) is associated with profound visuoperceptual impairments similar to dementia with Lewy bodies (DLB) but different from Alzheimer disease. These findings are consistent with previous neuroimaging studies reporting hypoactivity in cortical areas involved in visual processing in PDD and DLB.

Activities of Daily Living↗
PubMed1977

Children's comprehension of time-compressed speech: effect of speaker's familiarity.

An experiment was conducted with 42 third grade children from a parochial school system in a large metropolitan area. 21 classmates whose teacher served as the speaker for this experiment comprised the experimental group. A matched group of 21 classmates from another third grade classroom formed the control group. Each subject individually listened to a 940-word narrative passage that had been compressed at a rate of 45% or 275 words per minute. 10 questions about the material presented in the final three-fourths of the passage were asked of the subjects. The difference between the mean number of correct responses produced by the experimental group (5.5) and the control group (4.9) was not statistically significant. The results indicate that familiarity with the speaker does not facilitate 8-yr.-olds' comprehension of time-compressed speech.

Auditory Perception↗
PubMed1999

Rheologic determinant changes of erythrocytes in Binswanger's disease.

BACKGROUND: Binswanger's disease (BD) has been associated with severe arteriosclerotic changes in the long perforating arteries and with impaired cerebrovascular responsiveness to hypercapnia. Rheology parameters may become important factors in regulating cerebral blood flow. The purpose of this study was to investigate the changes in rheologic determinants of erythrocytes and to discuss the relation of erythrocytes and white matter lesions in this type of dementia. METHODS: Twenty-eight patients suffering from BD and a control group matched for age, sex and cerebrovascular risk factors were tested for the following hemorheologic variables: erythrocyte deformability, erythrocyte membrane fluidity, erythrocyte aggregation, plasma viscosity and whole blood viscosity. Additionally, red cell membrane metabolic parameters, lipids and individual membrane phospholipids, sialic acid (SA) and malondialdehyde (MDA) contents, and ATPase activities were measured. RESULTS: A significant decrease in erythrocyte deformability, erythrocyte membrane fluidity, membrane phosphatidylethanolamine, membrane phosphatidylcholine, membrane SA and membrane ATPase activities, and a significant increase in membrane cholesterol, cholesterol to total phospholipid ratio, MDA, broad viscosity and erythrocyte aggregation were observed in BD patients when compared with those of the matched control group. CONCLUSIONS: Changes in erythrocyte membrane parameters, especially in phospholipids, can produce serious metabolic disorders and influence the rheologic properties of erythrocytes in patients with BD. These alterations can contribute to a circulatory slowdown and may lead to worsening of the condition of the cerebral white matter in these patients.

Adenosine Triphosphatases↗
PubMedDate not supplied

Influence of timing of coronal preparation on retention of cemented cast posts and cores.

PURPOSE: This study investigated the effect of coronal preparation by high-speed handpiece on the retention of cemented cast posts and cores. MATERIALS AND METHODS: Cast posts and cores were fabricated for 90 extracted single-rooted human teeth cemented with zinc-phosphate cement and randomly divided into six groups of 15 specimens each. The six groups were matched randomly two by two, such that one of each of the matched groups was subjected to a 4-minute period of high-speed preparation of the cores. Castings from the first pair (1 and 2) were subjected to an axially directed removal force using a universal testing machine 15 minutes from the start of cement mixing; castings from the second (3 and 4) and third (5 and 6) pairs were tested at 1 hour and 24 hours, respectively, having been stored in water at 37 degrees C for the waiting periods. The forces required for dislodgment of posts from their prepared spaces were recorded. Data were statistically analyzed using two- and one-way ANOVA and the Student's t test. RESULTS: The results showed increased mean retentive strengths of posts as the time to testing increased for both unprepared and prepared groups. Significantly higher mean retentive strengths of posts were recorded for unprepared compared to prepared groups tested at 15 minutes and 1 hour after cementation. CONCLUSION: High-speed preparation had a significant negative effect on the retentive strengths of posts tested at 15 minutes and 1 hour after cementation, but not on those tested at 24 hours.

Analysis of Variance↗
PubMed1992

Diabetes in an elderly population. A controlled study of morbidity and outcomes.

OBJECTIVE: To determine in an elderly diabetic population the frequency of vascular and related disorders, the mortality, and outcomes compared with a matched control group. SETTING: The Queen Elizabeth Geriatric Centre, Ballarat, Victoria. METHOD: The medical records of all diabetics admitted between 1982 and 1987 inclusive, and a control group matched for age, sex and ward of admission were studied retrospectively. The presence of associated conditions and outcome parameters were entered in to a database and analysed statistically. RESULTS: Increased prevalence in individuals with diabetes of ischaemic heart disease (2.0:1.0), cerebrovascualr accident (1.9:1.0) and hypertension (1.5:1.0). Similar death rate, cumulative bed days, discharge destination and use of discharge services. CONCLUSION: Despite the more frequent presence of clinical vascular disease, an elderly population with diabetes had the same outcomes as matched controls and did not require more bed occupancy or use of community based services.

Aged↗
PubMed1994

Effects of viscosity and oxygen content on cerebral blood flow in ischemic and normal rat brain.

The mechanism of hemodilution-induced increases in cerebral blood flow (CBF) was investigated. Hemodilution was achieved with a molecular hemoglobin solution (DCLHb) and albumin which have similar viscosities but different oxygen carrying capacities. Part A: CBF was assessed in rats after one of the following regimens: (1) control-hematocrit not manipulated, (2) 30/Alb-hematocrit decreased to 30% with albumin, (3) 30/DCLHb-hematocrit decreased to 30% with DCLHb, or (4) 16/Alb/DCLHb-hematocrit decreased to 30% with albumin and then 16% with DCLHb. For viscosity matched groups (30/Alb and 30/DCLHb), CBF was greater in animals with decreased oxygen content (30/Alb); while in oxygen content matched groups (30/Alb and 16/Alb/DCLHb), CBF was greater in animals with decreased viscosity (16/Alb/DCLHb) (p < 0.05). Part B: Middle cerebral artery occlusion was performed, hemodilution achieved as in Part A, and CBF determined. For viscosity matched groups (30/Alb and 30/DCLHb), CBF was less in rats with decreased oxygen content (30/Alb); while in oxygen content matched groups (30/Alb and 16/Alb/DCLHb), CBF was greater in animals with decreased viscosity (16/Alb/DCLHb) (p < 0.05). This data supports the premise, that in normal brain, both viscosity and oxygen content effect CBF; while in ischemic brain, a decrease in viscosity but not oxygen content increases CBF.

Animals↗
PubMed2006

Should ileoanal pouch surgery be staged for patients with mucosal ulcerative colitis on immunosuppressives?

INTRODUCTION AND OBJECTIVE: Much debate has revolved around whether patients with mucosal ulcerative colitis (MUC) receiving immunosuppression should be weaned off immunosuppressives before undergoing ileal pouch surgery. Therefore, the aim of this study was to assess the affect of immunosuppressive drugs on postoperative complications after ileoanal pouch surgery. MATERIALS AND METHODS: A retrospective medical record review of patients with MUC who underwent ileal pouch surgery while taking immunosuppressive drugs such as azathioprine, 6-mercaptopurine (6-MP), methotrexate, and cyclosporin A was performed. Postoperative complications in the study group were compared to three matched groups: patients with MUC who had ileoanal pouch surgery while taking systemic steroids, patients with MUC not receiving any immunosuppressive drugs, and patients with familial adenomatous polyposis. RESULTS: Twenty-two patients with MUC who underwent ileoanal pouch surgery while taking immunosuppressive drugs were identified from a prospectively entered database of patients who had this surgery between 1988 and 2005. All but two patients underwent temporary fecal diversion. Fifteen patients were taking 6-MP or azathioprine; six were on cyclosporine A, and one both on azathioprine and cyclosporine A. Fifteen patients were also taking steroids at the time of ileoanal pouch surgery. Early (within 30 days of surgery) and late complications occurred in 36 and 50% of the study group patients, respectively, but did not significantly differ from a matched group of patients with MUC who did not take immunosuppressive drugs. Patients with familial adenomatous polyposis had a significantly lower long-term complication rate. CONCLUSION: This retrospective case-matched study suggests that the use of immunosuppressive drugs and cyclosporine A may not be associated with an increased rate of complications after ileoanal pouch surgery.

Adult↗
PubMed2006

Group-velocity-matched multistep cascading in nonlinear photonic crystals.

We demonstrate that simultaneous phase- and group-velocity-matched cascaded parametric processes can be achieved in two-dimensional quadratic nonlinear photonic crystals by proper matching of noncollinear processes with front tilting of the fundamental pulse. We present examples of cascaded third- and fourth-harmonic generation in a poled LiNbO3 planar structure.

Journal Article↗
PubMed2005

A radiographic study of tooth development in hypodontia.

OBJECTIVE: To investigate the radiographic development of permanent teeth in a group of children (66 females and 69 males, aged 3.08-15.02 years) with agenesis of one or more permanent teeth compared to a matched group. DESIGN: Tooth formation of all developing permanent teeth was assessed using Haavikko's method (1970) from dental panoramic tomographs. The difference between dental and chronological age was tested using a paired t-test. The correlation between the difference of dental and chronological age and severity of hypodontia was investigated using Spearman correlation test. In addition, radiographs of all children with only one single missing tooth in one quadrant and no more than two agenesis in total (N=59), were analyzed using the non-parametric Wilcoxon sign test, in order to investigate if the development of the teeth adjacent to the site of the agenesis was effected. RESULTS: Tooth formation in children with hypodontia was significantly delayed compared to the matched group (p<0.001). The mean difference was 1.51 years (S.D. 1.37 years). The severity of the hypodontia effected the magnitude of the delay (p<0.01). The teeth adjacent to the site of the agenesis were significantly delayed compared to the corresponding teeth in the matched group (p<0.01). CONCLUSION: These results confirm that the development of permanent teeth in children with hypodontia is different when compared with a matched group.

Adolescent↗
PubMed2000

The relationship between event representation and linguistic skill in narratives of children and adolescents with Down syndrome.

Children and adolescents with Down syndrome present with greater difficulty in expressive language than nonverbal cognitive domains. As narratives involve an understanding of the relationship(s) between events and their verbal expression, this divergence has implications for understanding narrative abilities in persons with Down syndrome. In this project, we investigated the relationship between event representation and linguistic expression in narratives of children and adolescents with Down syndrome (n = 31) and groups of typically developing children matched for mental age (n = 31), syntax comprehension (n = 28), or expressive language (n = 27). A short wordless film, the Pear Story (Chafe, 1980), was viewed individually by each participant and then each participant retold the story to an adult who (presumably) had not seen the film. Findings suggest a disparate relationship between linguistic expression and event representation in narratives of children and adolescents with Down syndrome. Participants with Down syndrome produced narratives that were significantly longer and more complex than the expressive-language-matched-group, with no differences observed in event structure when compared to the MA-matched group. Comparatively, use of linguistic devices and cohesion were poorer in the children and adolescents with Down syndrome than in the MA-matched children, with no differences observed in comparison to children matched for expressive language.

Adolescent↗
PubMed1992

Psychosocial adjustment among intellectually gifted adolescents: the role of cognitive-developmental and experiential factors.

Levels of psychological adjustment were examined among 51 high achieving, intellectually gifted adolescents with a mean age of 14.1 years. These students were compared with older adolescents matched with them on cognitive maturity (n = 30), and with two groups matched with them on chronological age (CA). One of the CA-matched groups contained children not identified as gifted (n = 47), while the other consisted of athletically talented youngsters (n = 39). All participants belonged to upper middle class families. On multiple indices of adjustment, intellectually gifted adolescents were comparable to older adolescents with similar cognitive skills, but differed from both groups of age mates. Differences between the gifted and non-gifted CA-matched groups were stronger than were those between the gifted group and the athletes of the same age. The findings were interpreted in terms of cognitive-developmental and experiential influences on psychological adjustment. The study also revealed gender effects which appeared to be linked with conflicts faced by gifted females between issues of achievement and those of social acceptance.

Achievement↗
PubMed2005

Disambiguation and mapping of new word meanings by individuals with intellectual/ developmental disabilities.

Wilkinson and Green (1998) reported that differences in the procedure by which new words were introduced to learners with cognitive impairments significantly affected their accuracy in later tests of receptive understanding of word meanings. However, a limited sample and no control group rendered the data preliminary. Here, I replicated and extended the research. First, a control group of preschool children, matched on receptive vocabulary age, was compared to individuals with intellectual disability of unspecified origin. Second, performance was also evaluated in three matched groups of varying etiology: unspecified, Down syndrome, and autism spectrum disorders. Performance on receptive word matching differed between preschool children and their matched experimental groups as well as among matched etiological groups.

Child↗
PubMed2000

Establishing the efficacy and cost effectiveness of community intensive case management of long-term mentally ill: a matched control group study.

OBJECTIVE: The study attempted to identify whether chronic mentally ill persons after receiving intensive case management (ICM) could demonstrate improved inpatient service utilisation compared with a matched control group cohort. Costings were measured to observe whether the increase in providing intensive outpatient contacts would be offset by savings in reduced inpatient service utilisation. METHOD: Eighty ICM patients were matched on ICD-9 diagnosis, age, gender, length of illness, age at first inpatient and outpatient contact, marital status, educational level, employment status, country of birth, year of arrival to Australia and religion. Inpatient bed-days and outpatient contacts were recorded and compared 12 months prior to ICM treatment, 12 and 24 months after ICM using within/between group repeated measures analysis of variance. RESULTS: The ICM group demonstrate significant reductions in inpatient service utilisation both within the 12- and 24-month period after receiving ICM treatment. The cost differential by 24 months of treatment was $801,475 in favour of the ICM model. The increase in costs of outpatient contacts were offset by a significant reduction in inpatient service utilisation. CONCLUSION: When outpatient contacts averaged one contact a week for the duration of the study period no significant reductions in inpatient service utilisation was recorded, as demonstrated by comparison with the matched control group. By increasing outpatient contacts by 3-4 contacts a week, inpatient contacts reduced by 36.8%. ICM is an efficacious and cost effective way to implement community-based services to the chronically long-term mentally ill.

Adult↗
PubMed1982

An analysis of the United States renal transplant patient population and organ survival characteristics: 1977 to 1980.

This study examines the relationship between renal transplant organ survival and the extent of HLA (human leukocyte antigen) A and B loci antigen matching. Combined dialysis and transplant records for patients in the End Stage Renal Disease Medical Information System (ESRD MIS), 1977 to 1980, were analyzed to examine transplant organ survival characteristics and changes in demographic pattern and donor types compared to previously reported studies of the United States transplant patients. Actuarial survival curves for high match (3 or 4 HLA A and B loci antigen matches) versus low match (0, 1, or 2 HLA A and B loci antigen matches) groups were analyzed for their relative difference and its statistical significance. In addition, this relationship was analyzed with controls for age, sex, race, mixed lymphocyte culture (MLC), crossmatch, and prior time on dialysis. For both cadaver and living related donor transplants, statistically significant differences were found between the survival curves of high and low match groups. Comparing low match and high match groups, there were differences in 1-year organ survival of 4.8 and 11.3%, respectively, for cadaver and living related donor transplants. MLC negative and crossmatch positive status appear to improve transplant organ survival beyond the effects of HLA matching. The study also designates several methodological problems inherent in transplant organ survival studies including: whether or not to include patient deaths as therapeutic failures, and whether or not to analyze transplant organ survival at one point in time or to compare overall survival curves for the entire study period.

Actuarial Analysis↗
PubMed2000

Passive ankle stiffness in subjects with diabetes and peripheral neuropathy versus an age-matched comparison group.

BACKGROUND AND PURPOSE: Patients with diabetes mellitus and peripheral neuropathy (DM and PN) often complain of joint stiffness. Although stiffness may contribute to some of the impairments and functional limitations found in these patients, it has not been quantified in this population. The purpose of this study was to quantify and compare passive ankle stiffness and dorsiflexion (DF) range of motion in subjects with DM and PN versus an age-matched comparison group. SUBJECTS: Thirty-four subjects were tested (17 subjects with DM and PN and 17 subjects in an age-matched comparison group). There were 10 male subjects and 7 female subjects in each group. METHODS: A Kin-Com dynamometer was used to measure passive plantar flexor torque as each subject's ankle was moved from plantar flexion into dorsiflexion at 60(/s. The following variables were compared using a Student t test: initial angle (angle of onset of plantar flexor torque), maximal dorsiflexion angle, plantar flexor muscle excursion (difference between initial angle and maximal dorsiflexion angle), slope of the first half of the plantar flexor torque curve (stiffness 1 measurement), and slope of the second half of the plantar flexor torque curve (stiffness 2 measurement). RESULTS: The subjects with DM and PN had smaller maximal dorsiflexion angles and less plantar flexor muscle excursion than the comparison group. There was no difference in initial angle, stiffness 1 measurement, or stiffness 2 measurement. CONCLUSION AND DISCUSSION: Although the subjects with DM and PN had less dorsiflexion range of motion than did the comparison group, there was no difference in stiffness between the groups. This finding suggests that people with DM and PN have "short" versus "stiff" plantar flexor muscles.

Adult↗
PubMed2005

Ultrabroadband beam splitter with matched group-delay dispersion.

We present a general design strategy for a broadband thin-film beam splitter with matched group-delay dispersion. By taking the substrate dispersion into account in the coating design, any combination of input and output can show the same dispersion for transmission and reflection. As a specific implementation, an ultrabroadband 50:50 beam splitter from 600 to 1500 nm for femtosecond laser applications was designed, fabricated, and characterized.

Journal Article↗
PubMed2000

In vitro CTL precursor frequencies do not reflect a beneficial effect of cross-reactive group (CREG) matching.

Adjustment of histocompatibility-based allocation criteria in kidney transplantation from HLA matching to matching on the basis of cross-reactive groups (CREG), was recently suggested to be a good alternative to transplant with more "well-matched" kidneys, without negatively influencing graft survival. Because graft rejection is often mediated by cytotoxic T cells (CTLs), we investigated whether a beneficial effect of CREG matching is reflected in vitro by lower CTL precursor frequencies (CTLpf). Therefore, CTLpf were determined in a group of healthy individuals and analyzed with respect to the number of HLA and CREG mismatches. A clear correlation was found between the number of HLA mismatches and the CTLpf, that is, the lowest mean frequency in case of 0 HLA-A, B mismatches (66 CTL precursors per 10(6) cells) and the highest in combinations with 4 HLA mismatches (mean = 303 CTLp/10(6) cells). The situation was different in the case of CREG mismatches. Although the highest frequency was found in the group of 4 CREG mismatches, no significant differences were observed between 0, 1, and 2 CREG mismatches. High CTLpf, up to 430/10(6), were even seen in the case of 0 CREG mismatches. Also within a well-defined group of single HLA-A or HLA-B mismatches no difference in CTLpf were observed between the subgroups with 0 vs. 1 CREG mismatches. The present study showed that in vitro the CTLpf correlates better with HLA than with CREG matching. These data are consistent with findings reported by several groups that matching for the CREG does not benefit transplant outcome.

Cross Reactions↗
PubMed1994

Internal fixation or hemiarthroplasty for undisplaced fractures of the femoral neck in octogenarians.

We compared the reoperation rate after internal fixation for minimally displaced or impacted intracapsular fractures of the femoral neck in patients aged 80 years and above with that in similar patients aged 65 to 79 years. We also compared the results of internal fixation with those of hemiarthroplasty for displaced intracapsular fracture in an age- and sex-matched group of elderly patients. We found that a significantly greater proportion of the older patients treated by internal fixation required reoperation than either the younger group or the age-matched group treated by hemiarthroplasty. Our results indicate that internal fixation may not be the best treatment for extremely elderly patients with minimally displaced or impacted intracapsular fractures of the femoral neck.

Aged↗