Cardiovascular and sympathetic nervous system responses to an acute stressor in borderline hypertensive rats (BHR)

The present study examined cardiovascular and plasma catecholamine responses to acute footshock stress in adult male Wistar-Kyoto (WKY) normotensive, borderline hypertensive (BHR), and spontaneously hypertensive (SHR) rats. Basal mean arterial pressure and heart rate were equivalent for SHRs and BHRs, and levels for both groups were elevated compared to WKYs. Following transfer to the footshock chamber, blood pressure increased to a greater degree in SHRs than in WKYs or BHRs. However, the tachycardia was exaggerated in both BHRs and SHRs compared to WKYs. In response to intermittent footshock stress, all groups had comparable heart rate increases while maintaining blood pressure near baseline levels. SHRs demonstrated a sympathetic hyperresponsiveness to footshock stress, with greater increases in plasma norepinephrine and epinephrine levels than WKYs immediately following footshock. At 5 minutes postfootshock, plasma catecholamines remained elevated in SHRs over both WKYs and BHRs. Plasma catecholamine increases following footshock were comparable at all time points between WKYs and BHRs. The present results demonstrate that sympathetic responsiveness of BHRs to acute footshock stress is more similar to normotensive WKYs than to hypertensive SHRs.     

HUMAN AND MURINE TUMOURS: CHANGES IN CELL SURFACE STRUCTURES CODED BY THE MAJOR HISTOCOMPATIBILITY COMPLEX REGION

Serological and structural changes of surface markers involved in immune reactions may occur in human and murine tumour systems. Thus nine out of twenty-one human tumour cell lines and SV₄₀-transformed fibroblasts differed from autologous lymphoblastoid cells or fibroblasts in their reactivity with HLA allonatisera. H-2 antigens isolated from the murine tumour cells 6C3HED and TP 1422, undergo structural changes. An alien HLA-B7 was detected in sera from two melanoma patients. The serologic activity on H-2 antigens was significantly increased in the serum and ascites fluid of tumour bearing mice. Additionally, human SV₄₀-transformed fibroblatsts acquire receptors for monkey red blood cells and the murine lymphosarcoma cells 6C3HED express receptors for sheep red blood cells.     

Consistency and change in functional status among older adults over time

Consistency and change between 1984 and the last reinterview (either two, four, or six years later) on 22 individual functional status markers and the five summary scales that they form are examined among the 5,986 members of the Longitudinal Study on Aging who were reinterviewed at least once. At baseline, at least three-fifths of the respondents are without limitations on any individual marker. At the last reinterview, at least 43.4% of the respondents are without such limitations. Among those who had limitations at baseline, at least one-fifth get better. For those without limitations at baseline, one-seventeenth to two-fifths get worse. Difficulties in walking and doing heavy housework were the most common, most likely to develop, and least likely to resolve of any of the ADL or IADL items, and lower body limitations were more common, more likely to develop, and less likely to resolve than upper body limitations. Linear panel analysis of the five summary scales indicates that the top predictors of increased functional limitation are baseline levels of functional limitation, older age, decedent status, and poorer perceived health (in that order). Other less consistent and less robust predictors include the length of the exposure window, being female, having a history of arthritis, lower educational attainment, having fewer nonkin social supports, higher prior physician visit levels, and not living alone.     

Lack of correlation between cerebrospinal fluid thyrotropin-releasing hormone (TRH) and TRH-stimulated thyroid-stimulating hormone in patients with depression.

BACKGROUND: It has been proposed that elevated central thyrotropin-releasing hormone (TRH) is associated with the blunted thyroid-stimulating hormone (TSH) response to TRH in patients with depression. Few studies have directly evaluated this relationship between central nervous system and peripheral endocrine systems in the same patient population. METHODS: 15 depressed patients (4 male, 11 female, 12 bipolar, and 3 unipolar) during a double-blind, medication-free period of at least 2 weeks duration, underwent a baseline lumbar puncture followed by a TRH stimulation test. Cerebrospinal fluid (CSF) TRH and serial serum TSH, free thyroxine, triiodothyronine, prolactin, and cortisol were measured. A blunted response to TRH was defined as a delta TSH less than 7 microU/mL. RESULTS: There was no significant difference in mean CSF TRH between "blunters" (2.82 +/- 1.36 pg/mL) and "non-blunters" (3.97 +/- 0.62 pg/mL, p = .40). There was no evidence of an inverse relationship between CSF TRH and baseline or delta TSH. There was no correlation between CSF TRH and the severity of depression or any other endocrine measure. CONCLUSIONS: These data are not consistent with the prediction of hypothalamic TRH hypersecretion and subsequent pituitary down-regulation in depression; however, CSF TRH may be from a nonparaventricular nucleus-hypothalamic source (i.e., limbic area, suprachiasmatic nucleus, brain stem-dorsal raphe) and thus, not necessarily related to peripheral neuroendocrine indices.     

Neuropsychological significance of anosmia following traumatic brain injury

OBJECTIVES: To investigate the incidence of anosmia following traumatic brain injury (TBI) using a standardized instrument and to test hypotheses that post-TBI anosmics perform significantly more poorly than do post-TBI normosmics on measures of executive skills and functional outcome. DESIGN: Prospective quasi-experimental between-groups design. PARTICIPANTS: Sixty-eight adults diagnosed with TBI. SETTING: Brain injury rehabilitation program based at a Midwestern medical center. MAIN OUTCOME MEASURES: University of Pennsylvania Smell Identification Test (UPSIT), selected neuropsychological measures of executive skills, the Disability Rating Scale (DRS), and the Community Integration Questionnaire (CIQ). RESULTS: Forty-four subjects (65%) demonstrated impaired olfaction; only 13 (30%) acknowledged smell dysfunction. Anosmic and normosmic groups did not differ in demographics, IQ, chronicity, or admission Glasgow Coma Scale (GCS). Anosmics had longer coma (P =. 01), more severe deficits in complex attention (Trailmaking Test, Part B, P =.01), new learning/memory (California Verbal Learning Test Trial V [CVLT-V], P =.001), and problem solving (Wisconsin Card Sorting Test [WCST], P =.001), leading to greater functional impairment (Disability Rating Scale [DRS], P =.003). No differences emerged on the CIQ. CONCLUSIONS: Anosmia is a common sequela of TBI, although only a minority of patients are aware of this deficit. Further, anosmics demonstrated greater impairment in a variety of frontal-lobe mediated executive functions, as well as greater functional disability.     

Intra-arterial prourokinase for acute ischemic stroke. The PROACT II study: a randomized controlled trial. Prolyse in Acute Cerebral Thromboembolism

CONTEXT: Intravenous tissue-type plasminogen activator can be beneficial to some patients when given within 3 hours of stroke onset, but many patients present later after stroke onset and alternative treatments are needed. OBJECTIVE: To determine the clinical efficacy and safety of intra-arterial (IA) recombinant prourokinase (r-proUK) in patients with acute stroke of less than 6 hours' duration caused by middle cerebral artery (MCA) occlusion. DESIGN: PROACT II (Prolyse in Acute Cerebral Thromboembolism II), a randomized, controlled, multicenter, open-label clinical trial with blinded follow-up conducted between February 1996 and August 1998. SETTING: Fifty-four centers in the United States and Canada. PATIENTS: A total of 180 patients with acute ischemic stroke of less than 6 hours' duration caused by angiographically proven occlusion of the MCA and without hemorrhage or major early infarction signs on computed tomographic scan. INTERVENTION: Patients were randomized to receive 9 mg of IA r-proUK plus heparin (n = 121) or heparin only (n = 59). MAIN OUTCOME MEASURES: The primary outcome, analyzed by intention-to-treat, was based on the proportion of patients with slight or no neurological disability at 90 days as defined by a modified Rankin score of 2 or less. Secondary outcomes included MCA recanalization, the frequency of intracranial hemorrhage with neurological deterioration, and mortality. RESULTS: For the primary analysis, 40% of r-proUK patients and 25% of control patients had a modified Rankin score of 2 or less (P = .04). Mortality was 25% for the r-proUK group and 27% for the control group. The recanalization rate was 66% for the r-proUK group and 18% for the control group (P<.001). Intracranial hemorrhage with neurological deterioration within 24 hours occurred in 10% of r-proUK patients and 2% of control patients (P = .06). CONCLUSION: Despite an increased frequency of early symptomatic intracranial hemorrhage, treatment with IA r-proUK within 6 hours of the onset of acute ischemic stroke caused by MCA occlusion significantly improved clinical outcome at 90 days.