Biomedical subjects

D M Reboussin

Publications and source records attributed to D M Reboussin.

At least 37 records · Page 2Linked to original sources

PubMed1997

Cerebral microvascular alterations in aging, leukoaraiosis, and Alzheimer's disease.

We have been using alkaline phosphatase (AP) histochemical staining, formerly a research tool for the study of cerebral cortical vascular morphology, to examine pathological changes in the cortex and deep cerebral structures. Deep structures stain similarly to the cortex. The AP stain is found in the afferent vessels (small arteries, arterioles, and capillaries), but not in venules and veins. The stain is also present in leaky vessels, such as those in the area postrema. The vascular supply to the cerebrum is not homogeneous. Supply to the deep white matter, for instance, derives from the leptomeningeal border zone, and then medullary arterioles must wind their way for up to 4 cm before arriving at their ultimate destination. Adding to the difficulties, tortuosities develop in some of these vessels with aging. According to some calculations, hypertensive levels of blood pressure would be required to maintain irrigation through some of these vessels. We have identified a venous alteration that attends aging: periventricular venous collagenosis (PVC) is a previously unrecognized, noninflammatory, mural disease of the periventricular veins. In severe cases, examples can be found of veins that are completely occluded by this process. PVC is found in 65% of subjects over 60 years old, and it strongly correlates with leukoaraiosis. In addition to previously mentioned aging-related changes, we have found extreme tortuosity, multiplications, and aneurysms of the smallest arterioles and lumpy-bumpy capillaries in the deep structures of patients with Alzheimer's disease.

Adult↗

PubMed1997

The economic impact of psoriasis increases with psoriasis severity.

BACKGROUND: Psoriasis treatments are known to be costly, but little is known about the financial impact of psoriasis and the way in which it relates to the severity of the disease. OBJECTIVE: This study was performed to obtain an estimate of the treatment costs faced by patients with psoriasis. METHODS: A total of 578 anonymous mail surveys were distributed to patients with psoriasis; 318 surveys were returned (55%). Psoriasis severity was assessed with the previously validated Self-Administered Psoriasis Area Severity Index (SAPASI). RESULTS: The total and out-of-pocket expenses to care for psoriasis were correlated with psoriasis severity (r = 0.26, p = 0.0001). There were no sex (p = 0.9) or racial (p = 0.4) differences in total expenditures. Severity was correlated with how bothersome to the patient was the cost of treatment (r = 0.30, p = 0.0001), the time required for treatment (r = 0.38, p = 0.0001), and the time lost from work (r = 0.23, p = 0.0001). Lower quality of life at work and in money matters also correlated with severity of psoriasis. Higher family income was associated with less time spent caring for psoriasis and less interference with work around the home. CONCLUSION: As expected, the expenses caring for psoriasis are greater for patients with more severe disease. These costs and other financial implications are associated with lower quality of life for patients with more severe psoriasis.

Absenteeism↗

PubMed1997

Suicidal ideation and behavior and noncompliance with the medical regimen among diabetic adolescents.

OBJECTIVE: To examine (1) the 1-year and lifetime prevalence of suicidal thoughts and behavior among adolescents with insulin-dependent diabetes mellitus (IDDM), (2) the relationship between suicidal thoughts and serious noncompliance with the medical regimen, and (3) factors including psychiatric disorder, self-efficacy expectations, and hopelessness that might mediate the relationship between suicidal thoughts and noncompliance. METHOD: Semistructured and structured interview instruments and self-report questionnaires were used to determine history of suicidal thoughts and behavior, serious noncompliance with the medical regimen, current psychiatric disorder, hopelessness, and self-efficacy expectations among 91 adolescents attending outpatient clinic appointments. RESULTS: The rate of suicidal ideation among the diabetic adolescents was higher than expected, but the rate of suicide attempts was comparable with that reported for the general population. Suicidal thoughts were strongly associated with serious noncompliance with the medical regimen. Duration of IDDM and psychiatric diagnosis were related to both suicidal ideation within the previous year and lifetime suicidal ideation. Diagnosable psychiatric disorder and not living in a two-parent home were related to noncompliance with medical treatment. CONCLUSIONS: Suicidal thoughts and serious noncompliance with the medical regimen are strongly associated among diabetic teenagers, and psychiatric disorder is a common correlate of both.

Adolescent↗

PubMed1997

Commercial tanning bed treatment is an effective psoriasis treatment: results from an uncontrolled clinical trial.

Phototherapy is highly effective in the therapy of psoriasis, but patient access to phototherapeutic facilities is not universal. Commercial tanning facilities are universal, but their efficacy in psoriasis treatment is unestablished. Our purpose was to conduct a study to assess the effect of a commercial tanning unit outfitted with nonprescription lamps on psoriasis. We conducted a 6-wk open study of 20 adult patients with stable psoriasis vulgaris. Clinical response was defined as a decrease in the Psoriasis Area Severity Index (PASI) or the Self-Administered PASI (SAPASI) by > or = 10%. There were 16 men and 4 women who participated with a mean (+/-SD) age of 43.0 +/- 14.8 y. Initial and final health-related quality of life information collected included the following instruments: the Brief Symptom Inventory (BSI), the Psoriasis-Related Stressor Scale (PRSS), and the Psoriasis Disability Scale (PDS). Side effects of tanning therapy were closely monitored. Fifteen subjects completed the entire 6-wk trial, and exit data on all subjects were used for analysis. The mean number of tanning sessions was 19 +/- 7.6 with a median of 19 and range of 3 to 29. Analysis of all 20 enrolled subjects found that 16 (80%) showed clinical response as measured by PASI, whereas 17 (85%) showed SAPASI response. Initial and final PASI scores decreased (p = 0.0001) from 7.96 +/- 1.77 to 5.04 +/- 2.5, and SAPASI scores also decreased (p = 0.02) from 11.8 +/- 4.4 to 7.9 +/- 7.7. When controlled for age and sex, a dose-response relationship was demonstrated with the PASI and SAPASI (p < 0.02). Decreases in the mean BSI and PRSS scales were demonstrated (p < 0.02), confirming the clinical significance of the reductions in disease severity scores. Episodes of mild burning occurred in 7 of 20 (35%) participants. Three subjects reported itching after one or two tanning sessions. This study showed that a tested commercial nonprescription tanning unit improved both psoriasis severity and health-related quality of life. Commercial tanning bed treatments may be a useful approach in patients unable to obtain office-based ultraviolet treatments.

Adult↗

PubMed1997

Human germinal matrix: venous origin of hemorrhage and vascular characteristics.

PURPOSE: To examine the vascular supply and architecture of the germinal matrix in the preterm neonatal brain and to determine whether veins or arterioles are the source of germinal matrix hemorrhage. METHODS: Brains from eight preterm neonates (24 to 35 weeks' gestation) and two full-term infants were fixed in alcohol, embedded in celloidin, sectioned at 100- and 500-micron thicknesses, stained for alkaline phosphatase, and examined with light microscopy. High-resolution contact radiographs of 500-micron-thick sections were also mounted on glass slides for microscopic examination. RESULTS: The upper and middle regions of the germinal matrix are supplied by branches of the lateral striate arteries, whereas the inferior part is supplied by branches of the recurrent artery of Heubner. In brain sections from four of the preterm infants, we found 15 circumscribed hemorrhagic foci within the germinal matrix. The largest was 5 mm in diameter; the smallest, 1 mm. All hemorrhages but one were closely associated with veins, with significant involvement of the perivenous space. The other hemorrhage appeared to be associated with an arteriole. In term and preterm infants, we found no arteriolar-to-arteriolar shunts, precapillary arteriolar-to-venules shunts, or vascular rete. At all gestational ages, the terminal vascular bed had only conventional branchings and connections. CONCLUSION: In preterm neonates, staining for endogenous alkaline phosphatase allows visual differentiation between afferent and efferent vessels. Germinal matrix hemorrhage in preterm neonates is primarily venous in origin. A hemorrhage can tunnel along the venous perivascular space, collapsing the vein and rupturing the tethered connecting tributaries. Extravasation of blood from the arterial circulation appears to be much less common.

Alkaline Phosphatase↗

PubMed1997

Extraesophageal pediatric reflux: 24-hour double-probe pH monitoring of 222 children.

Although extraesophageal gastric reflux has been implicated as a cause of many pediatric airway and respiratory diseases, its prevalence in these conditions remains unknown due to the relative lack of sensitivity and/or specificity of traditional reflux testing methods. A prospective study of 222 children (ages 1 day to 16 years) was performed with 24-hour double-probe (simultaneous esophageal and pharyngeal) pH monitoring. Seventy-six percent (168/222) of the study population had abnormal findings in either one or both of the pH probes. Of those, 46% (78/168) had pharyngeal reflux (extraesophageal gastric acid documented by the pharyngeal probe), despite having normal esophageal acid exposure times according to the esophageal probe. Thus, had the pharyngeal probe not been used, 46% of the children with documented extraesophageal (pharyngeal) reflux would have been falsely presumed to have normal reflux parameters. Patients with laryngeal abnormalities, pulmonary abnormalities, and emesis had significantly more pharyngeal acid reflux (p < .001) than patients with nonrespiratory symptoms. These data suggest that extraesophageal reflux may be underestimated by single-probe intraesophageal monitoring alone, and that laryngopharyngeal reflux may play a role in the pathogenesis of the conditions studied.

Adolescent↗

PubMed1996

First-time suicide attempters, repeat attempters, and previous attempters on an adolescent inpatient psychiatry unit.

OBJECTIVE: To compare clinical characteristics of hospitalized adolescents who (1) have recently made their first suicide attempt, (2) have recently made a second or subsequent attempt, (3) have made previous but no recent attempts, or (4) have never made an attempt. METHOD: Semistructured psychiatric diagnostic interviews were used to determine history of recent and previous suicidal behavior among 225 consecutively admitted adolescents to an inpatient psychiatric facility. Twenty-seven first-time attempters, 32 repeat attempters, and 40 previously suicidal youths were compared with 126 nonsuicidal youths in terms of severity of self-reported depressive symptoms, state anxiety, trait anxiety, state anger, and trait anger. RESULTS: Repeat attempters and previous attempters both reported more depressive symptomatology and trait anxiety than did nonsuicidal youths. In addition, youths with a previous history of suicide attempts, but no recent attempts, evidenced more trait anger than all other groups. First-time suicide attempters reported levels of distress that were intermediate to the other groups. CONCLUSIONS: Repeat attempters and previous attempters in hospital settings both report more distress than do nonsuicidal youths. Interventions should focus not only on resolution of immediate crises, but also on youths' ability to cope with ongoing difficulties that engender depression and chronic anxiety.

Adaptation, Psychological↗

PubMed1996

Statistical considerations in the use and analysis of single-subject designs.

Single-subject designs measure one individual's responses to some experimental manipulation. Statistical methods exist for validly estimating the effect of an intervention on a specific individual by using data from a single-subject design. However, without strong assumptions regarding how an intervention on one individual relates to its effects on others, the results from a single-subject design provide little useful information on the general utility of the intervention. Examination of a single subject cannot verify these assumptions. Correct analysis of data from such designs allows for the possibility of correlation among the observations and the modeling of any changes over time not related to an intervention effect. When data from single-subject designs are collected, the role of assumptions in both the analysis and the generality of conclusions must be frankly acknowledged. Research often develops in stages and the single-subject design can be useful in early stages for hypothesis generation.

Data Interpretation, Statistical↗

PubMed1996

Disease severity measures in a population of psoriasis patients: the symptoms of psoriasis correlate with self-administered psoriasis area severity index scores.

Because of the difficulty and expense of objectively measuring psoriasis severity, very little information exists on the severity of psoriasis in populations. We determined severity in a psoriasis patient population using the validated self-administered psoriasis area and severity index (SAPASI). This population consisted of 578 university dermatology clinic psoriasis patients, and data were analyzed from 317 (55%) questionnaire respondents. The majority of our sample was women (57%), and non-Caucasians represented a larger portion (8 %) in our sample compared with some previous studies. In our population, the reported frequencies of skin and joint symptoms were as follows: pruritus (95 %), skin burning (81 %), joint pain (69%), arthritis (51%), and psoriatic arthritis (20%). The SAPASI was significantly associated with severity of pruritus, burning, joint pain, and psoriatic arthritis. There was a significant negative correlation between the number of treatments employed and the SAPASI. This study provides results of a detailed measurement of the severity of psoriasis in a psoriasis patient population and relates this severity to population characteristics.

Adolescent↗

PubMed1996

The self-administered psoriasis area and severity index is valid and reliable.

The self-administered psoriasis area and severity index (SAPASI) is a structured instrument for measuring the severity of psoriasis. This study examines the validity, reliability, and responsiveness of the SAPASI. Trained personnel performed a psoriasis area and severity index (PASI) assessment on the same day a SAPASI was obtained from 80 subjects. The validity of the SAPASI was demonstrated using the PASI as the standard (r2 = 0.59, p = 0.0001). Significant correlations were found between SAPASI and PASI for body surface area (r = 0.62-0.75), erythema (r = 0.39), induration (r = 0.24) and scale (r = 0.38). Test-retest reliability was assessed in 19 subjects with repeated evaluations within 2 d. Correlations between the first and second SAPASI scores (r = 0.82) were highly significant (p = 0.0001). Inter-rater reliability of SAPASI body surface area measurements among five raters was very high (intraclass correlation coefficient R = 0.953). The SAPASI was responsive to changes in severity over time as demonstrated by correlation with changes in PASI scores (r = 0.63, p = 0.0002). We conclude that this structured patient self-report instrument facilitates quantitative assessment of psoriasis.

Evaluation Studies as Topic↗

PubMed1996

Risk factors for hospital utilization in chronic dialysis patients. Southeastern Kidney Council (Network 6).

It is not known if the risk factors for hospital utilization are similar to the risk factors for mortality in chronic dialysis patients. The risk factors associated with hospital days per year of patient risk were identified in a subset of patients in Network 6 (the states of North Carolina, South Carolina, and Georgia) who began dialysis in 1989. The demographic characteristics of this cohort of 1572 patients included a mean (+/- SD) age of 57.4 +/- 15.0 yr; 63.7% of the patients were African American, 52.4% were female, and 33.0% had diabetes mellitus as the primary cause of ESRD. The median number of hospital days per year of patient risk was 8.8, with 25th and 75th quartiles of 3.9 and 20.1, respectively. By using multiple regression analysis, the strongest predictors of the number of hospital days per year of patient risk included low serum albumin level (P = 0.0001), decreased activity level (P = 0.0006), diabetes mellitus as the primary cause of ESRD (P = 0.002), peripheral vascular disease (P = 0.004), white race (P = 0.01), increasing age (P = 0.03), the absence of hypertension (P = 0.03), and the presence of angina (P = 0.03), smoking (P = 0.03), and congestive heart failure (P = 0.045). These risk factors are similar to those reported for an increased risk of mortality in dialysis patients and some of them, such as smoking, are modifiable and may be amenable to interventional strategies.

Adult↗

PubMed1996

An assessment of potential problems of home phototherapy treatment of psoriasis.

Very little has been reported about how patients use home ultraviolet B (UVB) phototherapy. A survey of thirty-one patients who were prescribed a home UVB phototherapy unit to treat psoriasis was performed as a pilot study of home UVB phototherapy usage; twenty-two patients responded. Generally, respondents reported home UVB phototherapy to be very helpful for their psoriasis. We conclude that home UVB is an effective and appropriate treatment for many patients with psoriasis, but screening and education of candidates for home UVB phototherapy is important to ensure compliance with the treatment program.

Adolescent↗

PubMed1996

Alternative therapies commonly used within a population of patients with psoriasis.

Alternative therapies are known to be employed by dermatology patients. This study investigates the use of alternative medical treatments for psoriasis and the sociodemographic variables, conventional medical treatment, and psoriasis disease severity. Our study population consisted of 578 university dermatology clinic patients with psoriasis and data was analyzed from 317 (55 percent) questionnaire respondents. The majority of our sample were women (57 percent) and nonwhites represented 8 percent of our sample. Psoriasis severity was measured using the validated Self-Administered Psoriasis Area and Severity Index. Alternative medicine was used by 62 percent of respondents. Excluding sunlight and nonprescription tanning equipment, 51 percent used one or more of the remaining alternative therapeutic modalities. The psoriasis severity was worse in those who had tried herbal remedies, vitamin therapy, and dietary manipulation. With the exception of vitamin therapy, we observed no association between the intensity of conventional medical treatment and alternative treatment. The present or prior use of herbal remedies was correlated with the use of vitamin therapy and sunbathing, and dietary interventions were significantly correlated with vitamin therapy. Of the 113 (36 percent) who had used nonprescription tanning equipment for their psoriasis, 68 percent believed this modality was effective. We found that alternative medical therapies were widely utilized by subjects participating in this study. Clinicians need to continue to be aware of nonallopathic remedies employed by their patients to discover useful information about future therapies and to monitor for adverse effects.

Adolescent↗

PubMed1995

Brain microemboli associated with cardiopulmonary bypass: a histologic and magnetic resonance imaging study.

Emboli in brain tissue after cardiopulmonary bypass were reported in the literature 30 years ago, but there is little objective evidence confirming the presence of emboli in the brain after cardiopulmonary bypass with more modern equipment and techniques. Recently, with alkaline phosphatase vascular staining, we found an acellular fatty material in brain microvasculature from autopsy material of patients who died shortly after cardiopulmonary bypass. These fatty intravascular collections range in diameter from 10 to 70 microns, a size that lodges in the smallest vessels of the microvasculature. They have been found in numbers sufficient to cause detectable neurologic dysfunction and are believed, but not proved, to be emboli. By sequentially injecting colored microspheres, we can determine when emboli occur during experimental cardiopulmonary bypass. In ongoing related studies, magnetic resonance imaging was performed before cardiac valve replacement in 39 patients for whom preoperative and postoperative neurologic and neuropsychologic testing was available. Preliminary results suggest that magnetic resonance imaging evidence of prior stroke is not a significant risk factor for cognitive or motor decrement after cardiopulmonary bypass.

Animals↗

PubMed1995

Can we teach psychiatric residents to rate seizure regularity?

Despite recent advances in electroconvulsive therapy, clinicians still lack a reliable marker of treatment adequacy. Electroencephalographic (EEG) seizure morphology has been proposed as such a marker. However, the reliability of seizure ratings has not been assessed. We present the results of a study that examined how readily psychiatric residents could be taught to rate seizure morphology using a seizure regularity scale. We found that trainees could reliably rate seizure regularity and were particularly adept at discerning highly regular seizures from irregular ones. We believe that establishing reliable human scoring for electroconvulsive therapy seizure regularity justifies the position that human inspection of the ictal EEG should always complement computer analyses of seizure morphology.

Adult↗

PubMed1994

The effects of behavioral history on cocaine self-administration by rhesus monkeys.

The purpose of the present study was to examine whether a history of responding under schedules that generate either high or low response rates could modify previously established cocaine self-administration. Eight experimentally naive rhesus monkeys were trained to respond on one of two levers under a fixed-interval (FI) 5-min schedule of intravenous cocaine (0.03 mg/kg per injection) presentation. When responding was stable a cocaine dose-response curve (saline, 0.01-0.3 mg/kg per injection) was determined. Following completion of the dose-response curves, the monkeys were randomly assigned to one of two groups (n = 4/group) and trained to respond on the other lever under either a fixed-ratio (FR) 50 or inter-response times (IRT) > 30-s schedule of cocaine (0.03 mg/kg per injection) presentation. After 65 sessions responding was again maintained under the FI5-min schedule of 0.03 mg/kg per injection cocaine for 60 sessions, followed by redetermination of the cocaine dose-response curve. During the initial exposure to the FI schedule, the mean rate of responding was 4.02 (+/- 0.33) responses/min and the cocaine dose-response curve was characterized as an inverted-U shape function of dose, with peak responding at 0.03 mg/kg per injection. The FR50 schedule generated high rates (66.80 +/- 5.6 responses/min), while response rates under the IRT > 30-s schedule were low (2.62 +/- 0.2 responses/min). Following different behavioral histories, response rates under the FI5-min schedule were significantly higher for 60 sessions in FR-history monkeys compared to IRT-history subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Patient measurement of psoriasis disease severity with a structured instrument.

The Psoriasis Area and Severity Index (PASI) is used by dermatologic investigators to assess psoriasis disease severity. PASI measures are time-consuming and require trained personnel. We developed and evaluated a structured PASI-like instrument for self-measurement of psoriasis disease severity for use in future large-scale epidemiologic studies. The instrument consisted of a silhouette of a body for patients to shade in affected areas and of three modified visual analog scales for recording the redness, thickness, and scaliness of an average lesion. The resulting "patient PASI" score was compared to investigator PASI measurements in 43 patients with mild to severe psoriasis. Patients and investigator also recorded a subjective global severity score. The patient PASI score was highly predictive of the investigator PASI score (r2 = 0.71, p < 0.0001) and the investigator global score (r2 = 0.37, p < 0.0001). The patient global score was also predictive of the investigator PASI (r2 = 0.18, p < 0.0053) and the investigator global score (r2 = 0.10, p < 0.044), but these relationships exhibit wide predicted confidence intervals. Following the initial evaluation by 18.4 +/- 9.1 d of therapy, one-way t tests for paired samples (pre and post) showed significant improvements in the patient PASI (p < 0.003) and investigator PASI (p < 0.05). We conclude that although patients' overall scores may not allow for accurate prediction of clinical disease severity in a single individual, this structured instrument facilitates prediction of psoriasis disease severity in a population.

Adult↗

PubMed1994

Effects of caffeine pretreatment on measures of seizure impact.

Caffeine lengthens electroconvulsive therapy (ECT) seizures but has not been demonstrated to lower seizure threshold, nor to directly improve treatment outcome. We examined the effects of caffeine upon three recently proposed physiologic measures of seizure quality or impact: electroencephalography voltage suppression ratios, seizure regularity, and heart rate. None of these measures differed significantly in depressed inpatients randomly pretreated with either i.v. caffeine or saline on successive treatments during a course of right unilateral ECT. Newly defined measures of seizure impact may help identify ECT seizures of differing clinical efficacy, but these measures did not discriminate our caffeine and placebo conditions.

Aged↗