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At least 217 records · Page 12Linked to original sources
PubMed2002

The ontogeny of 25-hydroxyvitamin D(3) 1alpha-hydroxylase expression in human placenta and decidua.

In addition to its classical calciotropic effects, the active form of vitamin D, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) is a potent anti-proliferative/immunomodulatory secosteroid. The enzyme that catalyzes the synthesis of 1,25(OH)(2)D(3), 1alpha-hydroxylase (1alpha-OHase), is expressed in many human tissues, highlighting its possible role as an autocrine/paracrine activator of vitamin D. Immunohistochemical and RNA analyses were used to characterize the ontogeny of 1alpha-OHase expression in human placenta and decidua. Protein for 1alpha-OHase was detectable in trophoblast and decidua; the latter being stronger in decidualized stromal cells than macrophages, with no staining of lymphocytes. Quantitative reverse transcriptase-polymerase chain reaction was used to assess changes in mRNA expression for 1alpha-OHase at different gestations: first (mean, 9.1 +/- 1.5 weeks); second (mean, 14 +/- 1.8 weeks), and third trimester (mean, 39.3 +/- 2.5 weeks). 1alpha-OHase expression in decidua was approximately 1000-fold higher in first (95% confidence limits, 611 to 1376) and second (95% confidence limits, 633 to 1623) trimester biopsies when compared with the third trimester (95% confidence limits, 0.36 to 2.81) (both P < 0.001). In placenta, 1alpha-OHase expression was 80-fold higher in the first (range, 42 to 137) and second (range, 30 to 199) trimester when compared with third trimester biopsies (0.6 to 1.6) (both P < 0.001). Similar results were obtained by semiquantitative IHC. Parallel analysis of the receptor for 1,25(OH)(2)D(3) (vitamin D receptor) indicated that, as with 1alpha-OHase, highest levels of expression occurred in first trimester decidua. However, changes in vitamin D receptor mRNA expression across gestation were less pronounced than 1alpha-OHase. These spatiotemporal data emphasize the potential importance of 1alpha-OHase during early fetoplacental life and, in particular, suggest an autocrine/paracrine immunomodulatory function for the enzyme.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMed1986

Frequencies of hepatitis B, delta and HTLV-III virus markers in Saudi Arabia.

Serum samples from 608 residents of Saudi Arabia were examined for the presence of hepatitis B, delta and HTLV-III virus markers. The HBsAg carrier rate was 17% and the prevalence of all hepatitis B virus markers was 55%. Males between 16 and 25 years had a significantly higher prevalence of all HBV markers (69%; 95% confidence limits: 49%-82%) compared to females in the same age group (34%; 95% confidence limits: 25%-45%). The prevalence of HBsAg was significantly higher among males aged 25-35 years (24%; 95% confidence limits: 19%-40%) compared to females in the same age group (9%; 95% confidence limits: 4%-18%). In addition, the HBsAg carrier rate for all males (23%) was significantly higher compared to females (11%) (p less than 0.001). HBeAg was found in 12% of 89 HBsAg-positive individuals, 48% were anti-HBe positive and 40% were negative for both markers. Hepatitis B virus DNA was found in 11 of 41 individuals tested. Five of these were HBeAg positive and four were anti-HBe positive. Anti-delta was found in three of 36 HBsAg positive serum samples (8%). Of 485 individuals tested for anti-HTLV-III, none were positive.

Adolescent↗
PubMed1987

Propranolol in the prevention of first upper gastrointestinal tract hemorrhage in patients with cirrhosis of the liver and esophageal varices.

We conducted a prospective, randomized, multicenter, single-blind trial of propranolol as compared with placebo in the prevention of first upper gastrointestinal tract bleeding in patients with cirrhosis of the liver. A total of 230 patients (90 percent with alcoholism and 46 percent with a Child-Pugh grade C classification) with large esophageal varices without previous bleeding were randomly assigned to receive either propranolol (n = 118) or placebo (n = 112), after they had been divided into two groups according to the severity of their liver disease. The end points of the study were bleeding and death. The dose of propranolol was progressively increased to decrease the heart rate by 20 to 25 percent. The final doses were 40 mg of conventional propranolol and 160 and 320 mg of long-acting propranolol daily in 22 percent, 60 percent, and 18 percent of patients, respectively. The mean (+/- SD) follow-up time among survivors without bleeding was 436 +/- 172 days. The cumulative percentages of patients free of bleeding two years after inclusion in the study were 74 percent (95 percent confidence limits, 61 and 83) in the propranolol group and 39 percent (95 percent confidence limits, 15 and 69) in the placebo group (P less than 0.05). Cumulative two-year survival was 72 percent (95 percent confidence limits, 60 and 81) in the propranolol group and 51 percent (95 percent confidence limits, 37 and 64) in the placebo group (P less than 0.05). The advantage of propranolol over placebo was maintained when potentially confounding variables were adjusted with use of the Cox model. Side effects occurred in 17 percent of the patients who received propranolol and led to the stopping of treatment in 11 percent. We conclude that propranolol can decrease the incidence of first bleeding and death during a period of two years in patients with cirrhosis and large varices.

Clinical Trials as Topic↗
PubMed1990

Prognosis for twins with birth weight less than 1500 gm: the impact of cesarean section in relation to fetal presentation.

The purpose of this study of twins weighing less than 1500 gm was to evaluate the impact of cesarean section on intrapartum and neonatal mortality, as well as on cerebral palsy and mental retardation. National data held at the Medical Birth Registry was used for identification of cases. The original medical records were retrieved for 862 such twins born between 1973 and 1983. Twins with cerebral palsy and/or mental retardation born between 1973 and 1980 were identified by questionnaires to all rehabilitation centers for disabled children, offices for the Provision of Care for the Mentally Retarded, and to all local Boards of Education throughout Sweden. The analyses, including calculation of relative risk and 95% confidence interval, were performed after stratification for birth weight (250 gm classes) and period of delivery (1973 to 1976, 1977 to 1980, 1981 to 1983). The cesarean section rate increased from 7.7% (1973 to 1976), and 40.5% (1977 to 1980) to 68.9% (1981 to 1983). Concomitantly, intrapartum and neonatal mortality decreased markedly (51.7% to 29.1%) particularly for twin II but to a much lesser extent for twin I. The relative risk for intrapartum and neonatal mortality (vaginal/abdominal birth) did not increase significantly for twin I in vertex presentation (relative risk 2.0, 95% confidence limits 0.9 to 4.3), for twin I in breech presentation (relative risk 1.8, 95% confidence limits 0.7 to 4.3), for twin II in vertex presentation (relative risk 0.6, 95% confidence limits 0.2 to 1.6), or for twin II in breech presentation (relative risk 1.5, 95% confidence limits 0.7 to 3.0). The rate of cerebral palsy and/or mental retardation was 8.8% during 1973 to 1976 and 8.0 during 1977 to 1980 (chi 2 = 0.1, p greater than 0.05). For twins born in breech presentation the handicap rate in the first period (cesarean section rate 6.0%) was the same as in the second period (cesarean section rate 59.6%). The analysis failed to reveal any significant impact of abdominal birth on the fetal outcome for low-birth-weight twins, even when fetal presentation was taken into consideration.

Cerebral Palsy↗
PubMedDate not supplied

Ambulance collisions in an urban environment.

INTRODUCTION: Decisions to send an ambulance with or without lights and siren are made every day. While travel with lights and siren is presumed to have relatively more risk associated with it than travel without, little epidemiologic analysis has been conducted to compare the two modes of travel or to characterize collisions in general. OBJECTIVE: To characterize ambulance collisions and assess the risk of traveling with lights and siren in an urban 9-1-1 environment. METHODS: Retrospective analysis of all consecutive ambulance collisions of the Paramedic Division of the San Francisco Department of Public Health during a 27-month period. RESULTS: The overall collision rate for lights and siren (LS) travel was higher than that for non-lights and siren travel, although the difference was not statistically significant (45.9 collisions per 100,000 LS patient travels, 95% confidence limits 29.7, 62.1, versus 27.0/100,000 for non-LS travel, 95% confidence limits 18.3, 35.7). However, the rates of resulting injuries displayed a statistically significant difference (22.2 injuries per 100,000 LS patient travel, 95% confidence limits 11.0, 33.5, versus 1.5/100,000 for non-LS travel, 95% confidence limits -0.6, 3.5). While the majority of collisions (60.0%) occurred during patient-related travel, 35.6% occurred while the ambulance was available awaiting assignment, and 4.4% in a hospital parking lot. The majority of collisions were due to inattention, failure of on-coming traffic to yield, or unsafe parking; unsafe speed was an infrequent cause. Most crashes occurred during daylight, in dry weather, and involved another vehicle. CONCLUSION: There is some elevated risk for collision and added injury during lights and siren travel compared to travel without LS. The causes for these collisions suggest that interventions designed to improve driver skills and increase citizen awareness of an approaching ambulance could help reduce the number of collisions.

Accidents, Traffic↗
PubMed1994

Survival and short-term outcome in newborns of 23 to 25 weeks' gestation.

OBJECTIVES: We determined which factors are associated with survival and good short-term neurologic outcome in newborns of 23 to 25 weeks' gestation. STUDY DESIGN: We retrospectively reviewed the charts of all (n = 82) infants born alive at our hospital at 23 to 25 weeks' gestation from 1988 through 1991. We used univariate and multiple logistic regression analysis to compare survivors at hospital discharge with nonsurvivors and those with and without good short-term neurologic outcome. RESULTS: Survival rates were 19%, 59%, and 65% at 23, 24, and 25 weeks' gestation, respectively. A total of 90% of survivors had good short-term neurologic outcome. On multiple logistic regression analysis, female sex (odds ratio 8.7, 95% confidence limits 2.2 and 34), larger birth weight (odds ratio 2.5 per 100 gm increment, 95% confidence limits 1.3 and 4.9), and more advanced gestational age (odds ratio 5.3, 95% confidence limits 1.2 and 22 for 24 weeks; odds ratio 3.8, 95% confidence limits 0.6 and 22 for 25 weeks) were associated with survival. Female sex, more advanced gestational age, and larger birth weight were also associated with good short-term neurologic outcome. CONCLUSIONS: Good short-term neurologic outcome is possible in many survivors in this gestational age range. Factors other than gestational age may be considered when intervention in these pregnancies is contemplated.

Birth Weight↗
PubMed1988

Risk of nonocular cancer among retinoblastoma patients and their parents. A population-based study in Denmark, 1943-1984.

The risk of nonocular cancer among survivors of retinoblastoma has been investigated in a population-based study in Denmark, 1943 to 1984. None of the survivors had been treated with chemotherapeutic drugs. Forty-eight patients were treated with x-rays, and 102 patients were treated primarily with surgical removal of the eye(s). The overall relative risk (RR) for a new primary cancer was 4.2 (95% confidence limits, 1.1-11.5). In the subgroup of genetic retinoblastoma the risk was 15.4 (95% confidence limits, 2.6-50.8) and in the group of nonhereditary cancer the risk was 1.7 (95% confidence limits, 0.1-8.5). For all retinoblastoma patients the RR of bone cancer was 100 (95% confidence limits, 17-330). Parents not having retinoblastoma themselves were not at increased risk for nonocular cancer.

Adolescent↗
PubMed2003

Why do older adults decide they are having difficulty with a task?

OBJECTIVE: Previous studies have identified risk factors for decline in physical function, but they have not examined specific reasons older adults report difficulty with mobility tasks. DESIGN: Community-dwelling people ( n = 160) aged 59 yr and older in an observational cohort study were questioned to determine the most common cited reasons for self-reported difficulty in task performance. RESULTS: Mobility tasks were most often reported to be difficult (66%). The reasons cited for difficulty in low exercise tolerance tasks were task modification by method (33%) and rate (33%). For high exercise tolerance tasks, reasons cited included having to modify the rate of performing the task (20%) or the method (13%). Among those who reported difficulty with low exercise tolerance mobility tasks, >80% reported modification (odds ratio, 46.4 [95% confidence limits: 9.75, 220.51]) and 32% also report frequency change (odds ratio, 5.9 [95% confidence limits: 2.72, 12.85]) as the reason for perceiving difficulty. For those who reported difficulty performing high exercise tolerance-demanding tasks, >90% reported modification (odds ratio, 5.5 [95% confidence limits: 2.05, 14.88]) and 61% also report frequency changes (odds ratio, 3.9 [95% confidence limits: 1.93, 8.04]). CONCLUSION: The findings suggest that people are able to cite specific reasons for difficulty with mobility task performance, most commonly related to task modification.

Activities of Daily Living↗
PubMed1981

Methotrexate: an active drug in bladder cancer.

Forty-nine patients with transitional urothelial tract tumors received methotrexate: 0.5-1.0 mg/kg I.V. Q W (40 patients) or 250 mg/M2 in a 2-hour infusion with citrovorum factor rescue 24 hours later (nine patients). Eleven (26%, 95% confidence limits 13-39%) of 42 patients with bidimensionally measurable metastases achieved partial remission. Most responses occurred within 2-3 weeks and persisted for a median duration of six months (range, 2-20). Response rates were increased to 38% (6/16 patients, 95% confidence limits 18-65%) in patients who had no prior chemotherapy, and a 90-100% performance status (50, 5/10 patients, 95% confidence limits 22-78%) compared with 19% (5/26, 95% confidence limits 8-37%) in patients who had prior chemotherapy and a less than or equal to 80% performance status (19%, 6/32 cases, 95% confidence limits 9-32%). Toxicity included mucositis and myelosuppression. A review of the literature coupled with the present data suggest that methotrexate is as active as cisplatin in the treatment of patients with advanced urinary bladder cancer.

Adult↗
PubMed2000

Uncertainty of the hazardous concentration and fraction affected for normal species sensitivity distributions.

Species in the environment vary according to their sensitivity to a toxicant. Because these differences in sensitivity are unique to the toxicant at consideration and laboratory data sets to assess this variability are very small due to cost, it is important to provide uncertainty estimates of (1) environmental quality objectives (hazardous concentrations) derived from these laboratory data and (2) fraction of species affected at given, or predicted, laboratory or environmental concentrations. This article focuses on the normal (Gaussian) distribution of species sensitivity. It examines and compares results of Problems (1) and (2) from two opposing statistical philosophies, Bayesian and Classical, leading to vastly different numerical approaches. For the normal model, both approaches lead to identical answers, numerically. Extrapolation factors for the lower, median, and upper estimates of the hazardous concentration at six levels of protection are derived. Furthermore, upper, median, and lower estimates of the fraction affected at given, standardized, logarithmic concentrations have been tabulated. This table can be used directly for risk assessment without reference to protection levels or hazardous concentrations. The confidence limits for hazardous concentration and fraction affected depend heavily on the number of species tested and are independent of the toxic substance involved (provided the model is right), due to correction for the mean and standard deviation of the toxicity data. The equivalence of confidence limits for hazardous concentration and fraction affected is captured in the law of extrapolation: the upper (median, lower) confidence limit for the fraction affected at the lower (median, upper) confidence limit of the hazardous concentration is equal to the fraction affected (e.g., 5%) used to define the hazardous concentration. The upper confidence limit for the fraction affected at the median estimate of the hazardous concentration for 5% of the species is a fixed number depending on the sample size of the toxicity data only. It amounts to 46% at n=3, down to 20% at n=10, and still 12% at n 30.

Animals↗
PubMed1991

Geographical variance in the risk of gastric stump cancer: no increased risk in Japan?

Geographical differences may exist in the risk of gastric stump cancer. Therefore, we performed meta-analysis of literature reports in Japan (n = 3), the USA (n = 4), and Europe (n = 20) on the risk of postgastrectomy cancer. The weighted mean relative risk of stump cancer in Japan was 0.28, 95% confidence limits 0.21-0.38 as compared to 1.53, 95% confidence limits 0.98-2.41 in the USA and 1.66, 95% confidence limits 1.55-1.79 in Europe. Thus, the risk of gastric cancer in the post-gastrectomy patient seems decreased in Japan and is significantly less than in the USA or Europe, where an increased risk exists. Since there is a high risk of gastric cancer of the intact stomach in Japan, the discovery of a low cancer risk in the gastric stump may provide evidence that these gastric cancers are two different entities.

Duodenal Ulcer↗
PubMed1997

Effect of single-drug therapy on reduction of left ventricular mass in mild to moderate hypertension: comparison of six antihypertensive agents. The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents.

BACKGROUND: Antihypertensive drugs may differ in their ability to reduce LV mass. Covariates other than drug selection, such as pretreatment LV mass, body weight, the magnitude of blood pressure reduction, race, and age may modify the response of LV mass to therapy. METHODS AND RESULTS: Patients with mild to moderate hypertension (diastolic blood pressure, 95 to 109 mm Hg) were randomly allocated to treatment with atenolol, captopril, clonidine, diltiazem, hydrochlorothiazide, or prazosin in a double-masked trial. Patients achieving the goal diastolic blood pressure of <90 mm Hg during drug titration entered a 1-year maintenance period. Longitudinal analysis examined changes from baseline echocardiogram in LV mass at 8 weeks and at 1 year, statistically adjusted for pretreatment LV mass, systolic blood pressure, body weight, sodium excretion, physical activity, race, and age. Significant reductions at 1 year in adjusted LV mass were seen for patients in the highest tertile of pretreatment LV mass treated with hydrochlorothiazide (mean, -42.9; 95% confidence limits, -65.5, -20.2 g), captopril (mean, -38.7; 95% confidence limits, -61.0, -16.4 g), and atenolol (mean, -28.1; 95% confidence limits, -50.9, -5.3 g). These treatment effects differed from those of prazosin, diltiazem, or clonidine. CONCLUSIONS: Antihypertensive drugs have disparate effects on LV mass independent of the magnitude of blood pressure reduction. Patients with adequate blood pressure control on captopril, hydrochlorothiazide, and atenolol show a reduction of LV mass after 1 year of treatment, whereas patients on diltiazem, clonidine, or prazosin do not.

Adrenergic alpha-Antagonists↗
PubMed1988

Breast-feeding incidence and duration in black and white women.

The influence of sociodemographic factors on the incidence and duration of breast-feeding was evaluated in 668 black and 511 white women delivering their first child in the metropolitan Washington, DC, area. Breast-feeding rates were 84% among white and 49% among black women. Maternal educational level was strongly associated with breast-feeding, whereas the effect of ethnicity was moderate. Women with some college or some graduate school education had adjusted odds of breast-feeding that were 2.6 (95% confidence limit 1.9 to 3.7) and 5.2 (95% confidence limit 2.7 to 10.2) times higher than women with a high school education or less. In contrast, the adjusted odds of breast-feeding were 2.0 (95% confidence limit 1.4 to 3.1) times higher for white women compared with black women. The odds of breast-feeding increased among black women if they attended childbirth classes, were married, or were older. Among black women, the frequency of breast-feeding decreased sharply by 1 month postpartum. Breast-feeding duration for black v white women was 74% v 90% at 1 month, 44% v 72% at 4 months, and 26% v 50% at 7 months postpartum. The majority of black women (53%) used formula supplements in the hospital, which was the only factor significantly related to a shortened duration in this group (P less than .01). The high rate of formula supplementation among black women and its strong association with shortened duration of breast-feeding point to a need for more advice and support and less reliance on formula during the hospital stay.

Adolescent↗
PubMed1987

Long-term surveillance of mortality and cancer incidence in women receiving hormone replacement therapy.

This paper reports the preliminary results of a cohort study of 4544 British women receiving hormone replacement therapy (HRT). These women were recruited at 21 specialist menopause clinics around Britain. Up to the end of June 1983, the mean duration of HRT use per woman was 67 months of which, on average, 43% was 'opposed' use. In general, however, both the amount of progestogen given and the number of days per cycle for which it was given was less than would have been the case if the women had been receiving modern opposed therapy. The major focus of the study was to monitor mortality and cancer incidence in the cohort. The mortality results were broadly reassuring: overall mortality was significantly lower than expected on the basis of national rates (relative risk 0.58) and mortality ratios were below unity for all specific causes of death examined apart from cancer of the ovary (relative risk 1.43, 95% confidence limits 0.62-2.82) and suicide or suspected suicide (relative risk 2.53, 95% confidence limits 1.26-4.54). The most likely explanation for the latter finding is selection bias--thus at least 7 of the 11 women who died from suicide or suspected suicide had a psychiatric history before receiving HRT. The cancer incidence results were less reassuring, although they should be interpreted with some caution because cancer registry rates were used for comparative purposes. With this proviso, endometrial cancer risk was significantly elevated (relative risk 2.84, 95% confidence limits 1.46-4.96); many of the women concerned had taken therapy which was predominantly or entirely opposed although only one woman had received an opposed regimen which would now be considered adequately protective to the endometrium. Breast cancer incidence was also significantly increased (relative risk 1.59, 95% confidence limits 1.18-2.10); detailed analysis suggested that the use of unopposed ethinyl-oestradiol in particular might have undesirable effects on the breast.

Breast Neoplasms↗
PubMed1997

Reproducibility of dobutamine digital stress echocardiography.

The aim of this study was to investigate the temporal variability and interobserver agreement of dobutamine digital stress echocardiography. We performed two dobutamine stress echocardiographic studies (dobutamine up to 40 micrograms/kg/min and atropine up to 1 mg) in 15 patients with previous myocardial infarction at a mean of 19 days apart. Two observers assessed the wall motion using a six-point score in a 16-segment model and calculated the wall motion score index at rest and at peak stress by using a quad screen display. Analysis of the wall motion was performed separately on the day after each dobutamine stress test (analysis A), and all images from the serial studies in the same patient were simultaneously retrieved and compared side-by-side in the same view (analysis B). The mean values of heart rate and blood pressure were comparable for each in the two studies except for the heart rate at rest. Regarding the presence and absence of positive findings of dobutamine stress echocardiography, interobserver agreement was 93% (70% to 99% with 95% confidence limits, kappa value 0.86) in the patients and 93% (70% to 99% with 95% confidence limits, kappa value 0.80) in the three major vascular regions with the use of analysis A. these values did not improve with the use of analysis B. The agreement of the temporal variability was 93% (70% to 99% with 95% confidence limits, kappa value 0.86) in the patients and 84% (71% to 92% with 95% confidence limits, kappa value 0.66) in the vascular regions with the use of analysis A. These values further improved with the use of analysis B. With the comparison of the wall motion score index, interobserver variability showed a correlation coefficient of 0.88 at rest and 0.90 at peak stress with analysis A and 0.78 and 0.82, respectively, with analysis B. Corresponding analysis of temporal variability showed correlation coefficients of 0.99 at rest and 0.99 at peak stress when both analysis were used. Although dobutamine digital stress echocardiography has good reproducibility and negligible interobserver variability, even if the digital quad screen format is used, it requires strict standardization of the reading criteria and the objective measurements of wall motion in the expansion of this test to the evaluation of the changes in left ventricular function during more than two serial studies in the same patient.

Aged↗
PubMed2003

Comparison of detectability limits for elemental mapping by EF-TEM and STEM-XEDS.

The analytical sensitivity in terms of the signal-to-noise ratio (SNR) was investigated for elemental mapping by a transmission electron microscope equipped with an energy filter (EF-TEM) and a scanning transmission electron microscope with an X-ray energy dispersive spectrometer (STEM-XEDS). To compare the detectability limits of the elemental maps by the two techniques, homogeneous Cu-0.98+/-0.34 wt% Mn and Cu-4.93+/-0.49 wt% Mn thin specimens were used. Elemental maps can be considered as either an image or a spectrum. Therefore, the detectability limits of the elemental maps were characterized by the spectral SNR. To evaluate the detectability limits of the elemental maps with statistical confidence limits such as 1 sigma, 2 sigma and 3 sigma, the SNR values were reviewed from the statistical point of view. In STEM-XEDS mapping, the spectral SNR values improve as the specimen thickness increases since the signal intensity increases. Conversely, the spectral SNR in EF-TEM mapping is maximized at a certain thickness and then reduces as the thickness increases. To compare the two mapping techniques with regard to the analytical sensitivity, a method to estimate the minimum mass fraction (MMF) from measured signal and background intensities was developed. In this experimental approach, the MMF value can be evaluated by selecting the appropriate SNR value corresponding to the statistical confidence limits. In comparing the estimated MMF values from the two mapping approaches, EF-TEM mapping can be more sensitive than STEM-XEDS mapping up to specimen thicknesses <20-30 nm in the 1 sigma confidence limit and < approximately 50 nm in the 3 sigma limits. However, as the specimen thickness increases, the XEDS maps provide better detectability limits in the Cu-Mn dilute alloy specimens.

Journal Article↗
PubMed1989

Utilization of a new index to distinguish heterozygous thalassemic syndromes: comparison of its specificity to five other discriminants.

In 1984, a new index (the Makris index) combining erythrocytic and platelet parameters was described for the discrimination of the heterozygous thalassemic syndromes (beta and alpha). The algorithm is [(MCV/RDW)/(MPV/PDW)] divided by the RBC count in millions and requires for input the MCV, RDW, MPV, PDW, and RBC. The critical value used for separating the heterozygous thalassemic subjects is 1.84, which is the mean value plus 2 SD of our heterozygous subjects (confidence limit 95%). Because this index utilizes a confidence limit that includes 95% of affected persons, all individuals with values smaller than this need further investigation. It should be noted that the specificity of the index can be increased using the mean value of our heterozygous group plus 3 SD (X + 3 SD = 1.30 + 3*0.27 = 2.11, confidence limit 99%). In a series of 1510 "normal" subjects examined, 154 were designated as abnormals. None of the rest had abnormalities of cellular morphology or red cells osmotic resistance. The algorithm is readily incorporated into the software of an automated, whole blood analyzer. Using an expert system, we compared the sensitivity and specificity of the Makris index to five other discriminants (Mentzer, Shine et al., England et al., Green, and Bessman et al.). The Makris index distinguished between heterozygotes and normals without misdiagnosis.

Discriminant Analysis↗
PubMed1995

Normal sweat secretion rate in patients with alopecia areata.

We have examined sweat secretion rates in 22 patients with alopecia areata, and 22 age- and sex-matched controls. Mean sweat rate on the forearm in patients with alopecia areata was 20 mg/cm2 per h (95% confidence limits 15-25 mg/cm2 per h), and in controls was 24.1 mg/cm2 per h (95% confidence limits 19.1-29.1 mg/cm2 per h). Sweat secretion was higher in males than females in both the disease and control groups (27.8 mg/cm2 per h [95% confidence limits 21.3-34.3 mg/cm2 per h], compared with 18.08 mg/cm2 per h [95% confidence limits 14.63-21.6 mg/cm2]; P > 0.01). Our results confirm the previously reported sex difference in sweat secretion rate, and demonstrate that there is no statistically significant difference between patients with alopecia areata and controls. We discuss our results in the light of a previous report claiming that patients with alopecia areata have reduced rates of cholinergic-induced sweating.

Adult↗