Characterization of formaldehyde exposure resulting from the use of four professional hair straightening products.

An exposure simulation study was conducted to characterize potential formaldehyde exposures of salon workers and clients during keratin hair smoothing treatments. Four different hair treatment brands (Brazilian Blowout, Coppola, Global Keratin, and La Brasiliana) were applied to separate human hair wigs mounted on mannequin heads. Short-term (6-16 min) and long-term (41-371 min) personal and area samples (at distances of 0.5 to 3.0 m from the source) were collected during each treatment for the 1-day simulation. A total of 88 personal, area, and clearance samples were collected. Results were analyzed based on task sampling (blow-dry, flat-iron), treatment sampling (per hair product), and time-weighted averages (per hair treatment, four consecutive treatments). Real-time monitoring of tracer gas levels, for determining the air exchange rate, and formaldehyde levels were logged throughout the simulation. Bulk samples of each hair treatment were collected to identify and quantify formaldehyde and other chemical components that may degrade to formaldehyde under excessive heat. Mean airborne concentrations of formaldehyde ranged from 0.08-3.47 ppm during blow-dry and 0.08-1.05 ppm during flat-iron. During each treatment, the mean airborne concentrations ranged from 0.02-1.19 ppm throughout different zones of the salon. Estimated 8-hr time-weighted averages for one treatment per day ranged from 0.02 ppm for La Brasiliana to 0.08-0.16 ppm for Brazilian Blowout. For four treatments per day, means ranged from 0.04-0.05 ppm for La Brasiliana to 0.44-0.75 ppm for Brazilian Blowout. Using all four products in one day resulted in estimated 8-hr time-weighted averages ranging from 0.17-0.29 ppm. Results from bulk sampling reported formaldehyde concentrations of 11.5% in Brazilian Blowout, 8.3% in Global Keratin, 3% in Coppola, and 0% in La Brasiliana. Other products that degrade into formaldehyde were detected in Global Keratin, Coppola, and La Brasiliana. The results of this study show that professional hair smoothing treatments--even those labeled "formaldehyde-free"--have the potential to produce formaldehyde concentrations that meet or exceed current occupational exposure limits.

Stress and well-being in mothers of young children 11 years after the Chornobyl nuclear power plant accident.

BACKGROUND: This paper examines the association between exposure to the Chornobyl nuclear power plant explosion and the psychological and physical well-being of mothers with young children. The study also examines whether exposure to Chornobyl increased the vulnerability of mothers to subsequent economic and social stress, and thus represents a unique test of the stress-vulnerability model in a non-Western setting. METHOD: The sample consisted of mothers evacuated from the contamination zone surrounding the plant (evacuees) and mothers who had never lived in a radiation-contaminated area (controls). In addition to exposure status, the interview obtained data on perceived economic stress, social stress and stress moderators. The dependent variables were measured by the SCL-90 global severity index (GSI), perceived physical health and number of days unable to work due to illness. RESULTS: Overall, evacuees reported fewer stressors and greater personal and social resources than control mothers. Nevertheless, evacuees scored higher on the GSI, reported lower perceived physical health and took more sick days relative to control mothers, even after controlling for demographic factors, stressors and stress moderators. Tests of interaction effects were not statistically significant. CONCLUSIONS: The findings confirmed that married women with young children evacuated to Kyiv following the Chornobyl nuclear power plant explosion reported significantly poorer psychological and perceived physical health than controls 11 years later. Although perceived social and economic adversities also affected these outcomes, there was no evidence that exposure to the Chornobyl accident increased the vulnerability of mothers to these stressors, giving support to the additive burden model of stress.

Early adolescent marijuana use: risks for the transition to young adulthood.

BACKGROUND: This study assessed the relationship of early adolescent marijuana use to performance of developmental tasks integral to the transition to young adulthood. The tasks concerned intimacy, education, and work and social conformity. METHODS: African American (N = 617) and Puerto Rican (N = 531) youths completed questionnaires in their classrooms. Five years later they were individually interviewed. Logistic regression analysis estimated the increased likelihood that early marijuana users would make an inadequate transition to young adult social roles. RESULTS: Analyses examining the association between early marijuana use and 20 outcome variables found significant relationships for 10 of them: (a) having lower educational and occupational expectations; (b) being suspended or expelled from school, fired from jobs, 'high' at school or work, collecting welfare; and (c) rebelliousness, not participating in productive activities, not attending church, and being an unmarried parent. Marijuana use was not related to any of the intimate relationship measures. These finding emerged with controls on gender, ethnicity, age and mother's education. CONCLUSIONS: Among African Americans and Puerto Ricans, early marijuana use predicts less adequate performance on some developmental tasks integral to becoming an independent young adult. Marijuana is not a benign drug and is associated with future risks for the individual and society at large.

Mannitol bolus preferentially shrinks non-infarcted brain in patients with ischemic stroke.

Changes in brain tissue volume in six patients who had acute complete middle cerebral artery (MCA) infarctions and CT evidence of midline shift were measured using the brain boundary shift integral (BBSI) on sequential T1-weighted MR images acquired before and after a 1.5-g/kg bolus infusion of mannitol. At 50 to 55 minutes after the baseline scan, total brain volume decreased by 8.1 +/- 2.8 mL (0.6%, p < 0.005). Brain in the noninfarcted hemisphere shrank more (0.8 +/- 0.4%) than in the infarcted hemisphere (0.0 +/- 0.5%, p < 0.05).

Characteristics of closeness in adolescent romantic relationships.

This investigation was designed to describe characteristics of closeness in the romantic relationships of early, mid and late adolescents, and to determine whether adolescent reports of relationship authority and reciprocity are linked to perceptions of interdependence, interaction frequency, activity diversity, influence, and relationship duration. Age was positively associated with interdependence, daily social interaction, weekly activity diversity, and reciprocity but not with influence, authority, or relationship duration; gender was unrelated to all characteristics of closeness. Authority and reciprocity were each positively associated with relationship influence. Authority moderated associations between reciprocity and several characteristics of closeness such that reciprocity was positively linked to interdependence, daily social interaction, and weekly activity diversity, but only in relationships characterized by low levels of authority. Neither reciprocity nor authority was associated with relationship duration.

Hypoperfusion without ischemia surrounding acute intracerebral hemorrhage.

A zone of hypoperfusion surrounding acute intracerebral hemorrhage (ICH) has been interpreted as regional ischemia. To determine if ischemia is present in the periclot area, the authors measured cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), and oxygen extraction fraction (OEF) with positron emission tomography (PET) in 19 patients 5 to 22 hours after hemorrhage onset. Periclot CBF, CMRO2, and OEF were determined in a 1-cm-wide area around the clot. In the 16 patients without midline shift, periclot data were compared with mirror contralateral regions. All PET images were masked to exclude noncerebral structures, and all PET measurements were corrected for partial volume effect due to clot and ventricles. Both periclot CBF and CMRO2 were significantly reduced compared with contralateral values (CBF: 20.9 +/- 7.6 vs. 37.0 +/- 13.9 mL 100 g(-1) min(-1), P = 0.0004; CMRO2: 1.4 +/- 0.5 vs. 2.9 +/- 0.9 mL 100 g(-1) min(-1), P = 0.00001). Periclot OEF was less than both hemispheric OEF (0.42 +/- 0.15 vs. 0.47 +/- 0.13, P = 0.05; n = 19) and contralateral regional OEF (0.44 +/- 0.16 vs. 0.51 +/- 0.13, P = 0.05; n = 16). In conclusion, CMRO2 was reduced to a greater degree than CBF in the periclot region in acute ICH, resulting in reduced OEF rather than the increased OEF that occurs in ischemia. Thus, the authors found no evidence for ischemia in the periclot zone of hypoperfusion in acute ICH patients studied 5 to 22 hours after hemorrhage onset.

Autoregulation of cerebral blood flow surrounding acute (6 to 22 hours) intracerebral hemorrhage.

BACKGROUND: Arterial hypertension is common in the first 24 hours after acute intracerebral hemorrhage (ICH). Although increased blood pressure usually declines to baseline values within several days, the appropriate treatment during the acute period has remained controversial. Arguments against treatment of hypertension in patients with acute ICH are based primarily on the concern that reducing arterial blood pressure will reduce cerebral blood flow (CBF). The authors undertook this study to provide further information on the changes in whole-brain and periclot regional CBF that occur with pharmacologic reductions in mean arterial pressure (MAP) in patients with acute ICH. METHODS: Fourteen patients with acute supratentorial ICH 1 to 45 mL in size were studied 6 to 22 hours after onset. CBF was measured with PET and (15)O-water. After completion of the first CBF measurement, patients were randomized to receive either nicardipine or labetalol to reduce MAP by 15%, and the CBF study was repeated. RESULTS: MAP was lowered by -16.7 +/- 5.4% from 143 +/- 10 to 119 +/- 11 mm Hg. There was no significant change in either global CBF or periclot CBF. Calculation of the 95% CI demonstrated that there is less than a 5% chance that global or periclot CBF fell by more than -2.7 mL x 100 g(-1) x min(-1). CONCLUSION: In patients with small- to medium-sized acute ICH, autoregulation of CBF was preserved with arterial blood pressure reductions in the range studied.

Coping with psychotic symptoms in the early phases of schizophrenia.

How people diagnosed with schizophrenia cope with positive symptoms after their first hospitalization is explored, along with the relationship of their coping strategies to their psychosocial functioning. The strategies most frequently endorsed were cognitive in type, while those considered most helpful were behavioral. Respondents identifying an active strategy as most helpful displayed better psychosocial functioning at 24-month follow-up.

No reduction in cerebral metabolism as a result of early moderate hyperventilation following severe traumatic brain injury.

OBJECT: Hyperventilation has been used for many years in the management of patients with traumatic brain injury (TBI). Concern has been raised that hyperventilation could lead to cerebral ischemia; these concerns have been magnified by reports of reduced cerebral blood flow (CBF) early after severe TBI. The authors tested the hypothesis that moderate hyperventilation induced early after TBI would not produce a reduction in CBF severe enough to cause cerebral energy failure (CBF that is insufficient to meet metabolic needs). METHODS: Nine patients were studied a mean of 11.2+/-1.6 hours (range 8-14 hours) after TBI occurred. The patients' mean Glasgow Coma Scale score was 5.6+/-1.8 and their mean age 27+/-9 years; eight of the patients were male. Intracranial pressure (ICP), mean arterial blood pressure, and jugular venous oxygen content were monitored and cerebral perfusion pressure was maintained at a level higher than 70 mm Hg by using vasopressors when needed. Measurements of CBF, cerebral blood volume (CBV), cerebral metabolic rate for oxygen (CMRO2), oxygen extraction fraction (OEF), and cerebral venous oxygen content (CvO2) were made before and after 30 minutes of hyperventilation to a PaCO2 of 30+/-2 mm Hg. Ten age-matched healthy volunteers were used as normocapnic controls. Global CBF, CBV, and CvO2 did not differ between the two groups, but in the TBI patients CMRO2 and OEF were reduced (1.59+/-0.44 ml/100 g/minute [p < 0.01] and 0.31+/-0.06 [p < 0.0001], respectively). During hyperventilation, global CBF decreased to 25.5+/-8.7 ml/100 g/minute (p < 0.0009), CBV fell to 2.8+/-0.56 ml/100 g (p < 0.001), OEF rose to 0.45+/-0.13 (p < 0.02), and CvO2 fell to 8.3+/-3 vol% (p < 0.02); CMRO2 remained unchanged. CONCLUSIONS: The authors conclude that early, brief, moderate hyperventilation does not impair global cerebral metabolism in patients with severe TBI and, thus, is unlikely to cause further neurological injury. Additional studies are needed to assess focal changes, the effects of more severe hyperventilation, and the effects of hyperventilation in the setting of increased ICP.

Midazolam treatment of acute and refractory status epilepticus.

Generalized convulsive status epilepticus (GCSE) is a medical emergency requiring prompt resolution. Acute treatment is often delayed by difficulty in obtaining intravenous (i.v.) access. Refractory GCSE is often difficult to treat, and traditional therapy with barbiturates induces hypotension and respiratory depression and prolongs recovery. Midazolam is particularly useful for treating acute GCSE because it has an imidazole ring that is open at low pH, allowing it to be dissolved in aqueous solution for intramuscular injection, but closed at physiologic pH, increasing lipophilicity and rendering good intramuscular absorption, brain penetration, and fast onset of action. When given intramuscularly as a 0.2 mg/kg bolus, it has efficacy at least equal to that of i.v. diazepam, is well tolerated, induces little respiratory compromise, and has a shorter latency to onset of action. Therefore, it should be considered for the treatment of acute GCSE when i.v. access is problematic. For refractory GCSE, continuous i.v. midazolam infusion at 0.1-0.6 mg/kg/hr after a 0.2 mg/kg i.v. bolus is effective and has advantages over traditional therapies because it induces less hypotension and cardiorespiratory depression and can be easily titrated. Further prospective studies are needed to define the role of continuous i.v. midazolam compared to other contemporary therapies.

The effects of mannitol on cerebral edema after large hemispheric cerebral infarct.

OBJECTIVE: To evaluate the effect of a single large dose of mannitol on midline tissue shifts after a large cerebral infarction. BACKGROUND: Theoretically, mannitol use in the largest cerebral infarctions may preferentially shrink noninfarcted cerebral tissue, thereby aggravating midline tissue shifts and worsening neurologic status. To test this theory, we studied patients with hemispheric infarctions using continuous and sequential MRI during administration of a single dose of mannitol. METHODS: Patients with neurologic deterioration from complete middle cerebral artery (MCA) infarctions and CT evidence of at least 3 mm of midline shift were studied using T1-weighted three-dimensional multiplanar rapid acquisition gradient echo image data sets acquired at 5- to 10-minute intervals before, during, and after a 1.5 gm/kg bolus infusion of mannitol. Horizontal and vertical displacements were calculated by previously described methods. Glasgow Coma Scale (GCS) and MCA Stroke Scale (MCASS) were measured before and after mannitol administration. Mean changes in tissue shifts were compared using repeated measures analysis of variance. Clinical variables were compared using paired t-tests. RESULTS: Seven patients were enrolled. The final average change in midline shift compared with the initial displacement was 0.0 +/- 1 mm for horizontal (F = 0.06, p = 0.99) and 0.25 +/- 1.3 mm for vertical displacement (F = 0.06, p = 0.99). Whereas average scores for the group did not change, MCASS improved in two, GCS improved in three, and pupillary light reactivity returned in two patients. No patient worsened. CONCLUSIONS: Acute mannitol used in patients with cerebral edema after a large hemispheric infarction does not alter midline tissue shifts or worsen neurologic status.

Response to external ventricular drainage in spontaneous intracerebral hemorrhage with hydrocephalus.

We retrospectively reviewed consecutive intensive care unit patients with spontaneous supratentorial intracerebral hemorrhage (i.c.h.) and hydrocephalus who were treated with ventriculostomy to determine intracranial pressure (i.c.p.), Glasgow Coma Scale (GCS) score, and ventricular volume before and after ventriculostomy. Of 22 patients studied, ICP was controlled at < 20 mm Hg in 20. Only one patient had an improvement in both hydrocephalus and GCS. The three patients who survived to 3 months (modified Rankin scores of 0, 0, and 1) were characterized by very small ICH volumes and stable or improving hydrocephalus and GCS.

Management of hypertension in acute intracerebral hemorrhage.

Hypertension commonly occurs in the acute period following spontaneous intracerebral hemorrhage. Management of this hypertension is controversial. Some advocate lowering blood pressure to reduce the risk of bleeding, edema formation, and systemic hypertensive complications, whereas others advocate allowing blood pressure to run its natural course as a protective measure against cerebral ischemia. This article reviews the pertinent clinical and experimental data regarding these issues and briefly discusses the use of antihypertensive agents commonly administered in this setting.

Regional cerebral glucose utilization in withdrawal following systemic and intracerebroventricular sufentanil administration.

Regional cerebral glucose utilization (RCGU) and behavior were studied during naloxone-precipitated withdrawal in rats after chronic intravenous (IV) or intracerebroventricular (ICV) administration of sufentanil citrate, a potent, highly selective mu opiate agonist. Changes in RCGU were indistinguishable between the two groups (p < 0.05) in 21 of 24 anatomically related limbic and brainstem structures known to be activated during withdrawal. Rats made dependent by ICV infusions of sufentanil had smaller RCGU changes in the lateral septal areas, lateral habenular nuclei and paratenial nuclei than rats made dependent by IV infusions of sufentanil. These observations are consistent with infusion artifact, given the proximity of these structures to the site of IVC infusion. All 24 structures had increased RCGU in experimental groups compared with controls (p < 0.05). Although linear regression analysis suggests slightly greater RCGU changes in rats after IV sufentanil than in rats after ICV sufentanil (m = 0.81), the changes in corresponding structures are highly correlated (r = 0.96) indicating qualitatively almost identical RCGU changes. Behavioral changes paralleled RCGU changes and revealed slightly greater withdrawal in rats after IV sufentanil but no clear qualitative differences. Taken together, these results suggest that cerebral metabolic changes in withdrawal following chronic sufentanil administration result exclusively from effects at CNS opiate receptors and not from peripheral receptors. Additionally, the current study provides a model for the production of opiate dependence, by the ICV administration of a specific mu opiate receptor agonist that is relatively free of infusion artifact.

The interpersonal context of mental health interviews.

Little is known about the composition and effects of the interpersonal contexts in which epidemiological interviews are conducted. The Epidemiological Catchment Area (ECA) study affords an opportunity to examine the frequency and impact of third party presence. Almost half of the interviews at the Los Angeles site of the ECA study were conducted in the presence of a third part, typically the spouse or child of the respondent. Results indicate that third party presence is not related either to reports of symptoms or to performance on a test of cognitive impairment. Although findings suggest that respondents are not influenced by the presence of others, they may also reflect a variety of cultural, situational, and methodological processes.

Is morphine dependence mediated exclusively by the Mu receptor?

Regional cerebral glucose utilization (RCGU) and behavior during naloxone precipitated withdrawal were studied in rats made dependent on either sufentanil, a highly selective mu opiate agonist, or morphine. Changes in RCGU during withdrawal in 23 of 24 anatomically related limbic and brainstem structures were indistinguishable between rats dependent on morphine or sufentanil. Linear regression analysis indicated that RCGU changes during withdrawal in these two groups were highly correlated (r = 0.95). Withdrawal behaviors (autonomic signs of withdrawal, jumps, weight loss, and incidence of diarrhea) were likewise indistinguishable between the two groups. The correlations of both these measurements of dependence suggest that chronic occupation of mu opiate receptors alone is sufficient to produce dependence that is indistinguishable from morphine dependence.

Dependence and withdrawal following intracerebroventricular and systemic morphine administration: functional anatomy and behavior.

Regional cerebral glucose utilization (RCGU) and behavior during precipitated morphine withdrawal were studied in rats made dependent by either intracerebroventricular (i.c.v.) or subcutaneous (s.c.) administration of morphine. [14C]2-deoxy-D-glucose autoradiography revealed that RCGU increased in an anatomically related group of limbic and brainstem structures in rats that were in morphine withdrawal precipitated by naloxone administration compared to morphine-dependent controls that were not in precipitated withdrawal. Correlation of RCGU for 24 brain structures comparing i.c.v. vs s.c. morphine-treated rats was highly significant for groups in withdrawal and for controls (r values, 0.958 and 0.971, respectively). Withdrawal behaviors including autonomic signs of withdrawal, withdrawal jumping, and incidence of diarrhea were not different between the two groups in withdrawal (i.c.v. and s.c.). Weight loss during withdrawal increased (P less than 0.05) in rats made dependent by s.c. morphine administration compared to rats that received morphine by the i.c.v. route. Taken together, these results indicate that RCGU changes during morphine withdrawal result solely from effects of chronic morphine in the central nervous system, not in peripheral sites. The increased weight loss of s.c.-treated, morphine-dependent rats in withdrawal suggests an independent peripheral effect perhaps mediated by visceral opiate receptors.

Screening for learning disabilities: a neuropsychological approach.

The ability of the Trail Making Test (TMT) and Tactual Performance Test (TPT) to discriminate between learning-disabled and normal children was examined. Twenty children aged 9 to 14 years who recently had been classified as learning disabled and 20 matched controls were administered individually the TPT, TMT, and two experimental forms of the TMT (parts X and Y). The data from the two groups were analyzed with a discriminant analysis. An overall accuracy rate of 82.5% was obtained when the measures were used to predict the classification status of individual children. A stepwise discriminant analysis procedure revealed an experimental form of the TMT (part X), Tactual Performance Test total time, and Tactual Performance Test localization to be the most sensitive measures. The use of such measures to screen for learning disabilities is discussed.