bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxygen tension under hyperbaric conditions in healthy pig brain
Authors: van Hulst Robert A. , Haitsma Jack J , Klein Jan , Lachmann Burkhard 
Published: May 2003

SummaryObjective: To investigate the effect of hyperbaric conditions on brain oxygenation, intracranial pressure and brain glucose/lactate levels in healthy non‐brain‐traumatized animals.Design and setting: Prospective animal study in a hyperbaric chamber.Subjects: Twelve adult Landrace/Yorkshire pigs.Interventions: The animals were normoventilated in a pressure‐controlled mode according to the open lung concept first at normobaric pressures (FiO2 of 0·4 and 1·0) and subsequently in the hyperbaric chamber at 1·9 and 2·8 bar (both at an FiO2 of 1·0). Under these conditions brain oxygen tension and intracranial pressure were recorded and brain glucose/lactate levels were measured by microdialysis.Results: At normobaric conditions, increasing the FiO2 from 0·4 (baseline) to 1·0 resulted in a significant increase in brain oxygen tension from 33 ± 14 to 63 ± 28 mmHg (P<0·05). Compared with baseline, both hyperbaric conditions (at an FiO2 of 1·0) led to a significant increase in brain oxygen tension to 151 ± 65 mmHg (P<0·001) at 1·9 bar and to 294 ± 134 mmHg (P<0·001) at 2·8 bar.Conclusions: If there is a need for increased oxygenation in the brain, then one way to achieve this is to apply hyperbaric conditions at 100% oxygen. Compared with an atmospheric pressure with a FiO2 of 0·4, a nine‐fold increase (900%) in PbrO2 values can be reached by increasing the FiO2 to 1·0 and the pressure to 2·8 bar. In this study, hyperbaric oxygen pressure in the brain did not lead to changes in intracranial pressure or in brain glucose/lactate levels.
Hyperbaric hyperoxia induces a neuromuscular hyperexcitability: assessment of a reduced response in elite oxygen divers
Authors: Jammes Yves , Arbogast Sandrine , Faucher Marion , Montmayeur Alain , Tagliarini Ferdinand , Meliet Jean Louis , Robinet Claude 
Published: May 2003

SummaryWe compared the changes in compound muscle mass action potential (M‐wave) recorded in vastus lateralis in response to hyperbaric hyperoxia (HBO) in nine combat divers who dived daily while breathing 100% O2 or O2‐enriched mixture (O2 divers) to those measured in eight recreational divers who dived occasionally using compressed air/21% O2 (air divers). The O2 divers completed a 6‐h HBO exposure in which the inspired oxygen pressure (PiO2) varied from 1·15 to 2·7 absolute atmospheres (ATA), PiO2 being maintained at 1·15 ATA throughout the first 2‐h period, whereas the air divers only completed a 2‐h HBO exposure with PiO2 constant at 1·15 ATA. Before HBO exposure, there were no intergroup differences between baseline M‐wave characteristics (amplitude and duration), but the conduction time was significantly shorter in O2 divers compared with air divers. After 90 min of HBO (1·15 ATA) the air divers demonstrated neuromuscular hyperexcitability, as evidenced by an increased M‐wave amplitude (13%, P<0·01 versus baseline), shortened M‐wave duration (5%, P<0·05 versus baseline), and reduced conduction time (5%, P<0·01 versus baseline). In O2 divers, similar HBO‐induced M‐wave changes were only observed when PiO2 was greater than 1·50 ATA. We conclude that HBO elicites neuromuscular hyperexcitability, attenuated in elite O2 divers.
Effects of experimental changes in nasal airway pressure on mucosal output of plasma
Authors: Berg Søren , Wollmer Per , Andersson Morgan , Persson Carl G. A. , Greiff Lennart 
Published: May 2003

SummaryMicrovascular extravasation, lamina propria flooding and luminal entry of plasma are key features of airway inflammation. We have suggested that the extravasated plasma moves across the epithelial lining along hydrostatic pressure gradients. The present study, involving healthy subjects, tests this hypothesis by examining effects of experimentally applied negative and positive luminal pressures on nasal output of plasma at baseline and at histamine‐induced plasma exudation. The negative (−10 cmH2O) and positive (10 cmH2O) pressures were applied for 10 min after nasal spray administrations of diluent (saline) and histamine (0·5 mg). The mucosa was then lavaged and the lavage fluid levels of α2‐macroglobulin were measured as index of plasma exudation. Nasal administrations of diluent and histamine (0·5 mg) were also carried out without any pressure applications. Histamine produced significant mucosal exudation of plasma. The negative luminal pressure augmented this response significantly as well as the baseline appearance of α2‐macroglobulin in mucosal surface liquids. We conclude that extravasated plasma may be moved across the epithelium by a hydrostatic pressure‐operated epithelial mechanism.
Effect of non‐hypotensive haemorrhage on plasma catecholamine levels and cardiovascular variability in man*
Authors: Haberthür Christoph , Schächinger Hartmut , Seeberger Manfred , Gysi Christine Stebler 
Published: May 2003

SummaryBackground: It is well known from animal research that non‐hypotensive haemorrhage produces sympathoexcitatory responses assessable by both the rise in plasma catecholamine levels and the shift of autonomic influences on the heart to more sympathetic and less parasympathetic control. Data in humans are restricted.Methods: Heart rate variability (HRV), systolic blood pressure (FINAPRES) variability (BPV), and catecholamine plasma levels were measured before and after haemorrhage in 30 healthy blood donors and compared with those from 10 control subjects without blood loss. Spectral power of HRV and BPV in very low (0·02–0·06 Hz), low (0·07–0·14 Hz), and high (0·15–0·40 Hz) frequency bands were calculated by Fourier analysis. Catecholamine plasma levels were assayed by dual column reverse‐phased high‐performance liquid chromatography (HPLC).Results: Haemorrhage of 5·6 ± 1·2 ml kg−1 body weight increased plasma norepinephrine levels (215 ± 92 pg ml−1 versus 254 ± 95 pg ml−1; P = 0·002), increased BPV in the low frequency band (Mayer waves; 1·8 ± 1·0 ln [mmHg2] versus 2·0 ± 0·9 ln [mmHg2]; P = 0·021), and decreased the vagally transmitted high frequency HRV (6·9 ± 1·1 ln [MI2] versus 6·5±1·2 ln [MI2]; P<0·0001), but did not induce significant changes in heart rate (66 ± 11 bpm versus 67 ± 11 bpm; P = 0·79) and arterial blood pressure (mean values: 84 ± 13 mmHg versus 87 ± 13 mmHg; P = 0·12).Conclusions: As suggested by plasma norepinephrine levels, systolic BPV and HRV, non‐hypotensive haemorrhage produces sympathoexcitatory responses as well as vagal withdrawal of heart rate control in humans.
Reference values for the physical work capacity on a bicycle ergometer for men – a comparison with a previous study on women
Authors: Wohlfart Björn , Farazdaghi Gholam R. 
Published: May 2003

SummaryThe aim of the study was to collect new reference values for the clinical ramp exercise test on bicycle, because in our experience, the commonly used values were too low. A group of healthy men (n = 81, 20–80 years) was randomly selected from the local municipal register to achieve an even distribution in age. Data were compared with those obtained in a similar, previous study on women (n = 87). The subjects were encouraged to cycle until exhaustion (19 on the Borg scale) when maximal load, heart rate and systolic blood pressure were recorded. Maximal load (Wmax) was related to age (years) and height (m) using a non‐linear function: Wmax = (244·6 × height − 92·1)/{1 + exp[0·038 × (age − 77·3)]}. Maximal heart rate (HRmax) was described by a similar function: HRmax = 203·7/{1 + exp[0·033 × (age − 104·3)]}. The maximal systolic blood pressure (BPmax) was described by a linear function based on age: BPmax = 0·505 × age + 192. Similar functions for the women are also given. It is suggested that 80–120% of the predicted maximal load can be taken as a reference interval for both men and women and similarly 90–110% of the maximal heart rate. In this study, 84% of the men reached a maximal load within the reference interval and 93% maximal heart rate within the reference interval. The reported values for maximal load were 104–132% of the reference values published by others.
Postural sway in normal subjects aged 20–70 years
Authors: Røgind H. , Lykkegaard J. J. , Bliddal H. , Danneskiold‐Samsøe B. 
Published: May 2003

SummarySo far, no population‐based reference material of postural sway has been presented in the literature. This study evaluated postural control by measuring posturographic parameters, with the aim of establishing useful standards with regard to gender, age, body weight, cigarette smoking, alcohol consumption and articular hypermobility. This was performed in an age‐stratified random sample of 195 subjects from the Copenhagen City Heart Study, of whom, 133 agreed to participate. Measurement of postural sway was performed the Balance Master Pro®. Outcome parameters were average angular velocity, target sway area, per cent maximum stability and per cent ankle strategy. Using SAS Proc Mixed, backward stepwise elimination was performed and 95% prediction intervals were obtained. Sway increased with increasing difficulty of the test (P<0·001) and with increasing age (P<0·001). No differences were found between the sexes. Ankle‐strategy did not change with age, but decreased with increasing body weight, and increased in subjects reporting a consumption of modest amounts of alcohol (P<0·001), or with the finding of increased hypermobility (P = 0·006). The present material may be used as a reference in further studies of postural control.
Vascular dementia from a viewpoint of cerebral blood flow and oxygen metabolism
Authors: Tanaka Makoto , Kondo Susumu , Okamoto Koichi , Hirai Shunsaku 
Published: May 2003

AbstractVascular dementia is as common as Alzheimer's disease in Japan, although its importance has not been duly appreciated and its pathoetiology has not attracted proper attention. This article reviews the importance and pathophysiology of vascular dementia, presenting data obtained from our positron emission tomography (PET) study. Moreover, PET, ultrasonic quantitative blood flow measurements and magnetic resonance imaging findings on two ischemic conditions that may lead to vascular dementia are shown; chronic cerebral circulatory insufficiency (CCCI) and asymptomatic cerebral infarction. The review begins by describing the brief history, definition and classification of vascular dementia. Then, a detailed description of our PET study on patients with dementia as a result of cerebral infarction follows. Vascular dementia includes a large infarction in the territory of the right middle cerebral artery (LID), Binswanger‐type infarction (BiD), multiple infarcts in the white matter and the basal ganglia (MID) and left anteromedial thalamic infarction (ThD). In addition, patients with a large infarction in the territory of the right middle cerebral artery (LIN), who did not have dementia, were used as a control group for LID. Healthy volunteers were also examined. This study demonstrates two types of dementia. Dementia observed in LID, MID and BiD reveals an overall reduction of blood flow and oxygen metabolism, which is accentuated in the frontal lobes. The second type, observed in ThD, shows a significant reduction in blood flow and oxygen metabolism in a relatively localized area in the left frontal lobe and the ipsilateral infarcted area. The etiological difference between the two types of dementia and the possible importance of frontal lobe hypoperfusion and hypometabolism are discussed. The review also examines the most important factor in dementia with multiple lacunae, concluding that widespread cerebral ischemia appears to be the most crucial factor. Finally, data on CCCI and asymptomatic cerebral infarction are described, which reveal that even these pre‐stroke conditions have mild but significant hypoperfusion, concluding that preventive measures should be taken before ischemia advances.
Ischemic white matter damage and cognitive impairment
Authors: Yamauchi Hiroshi 
Published: May 2003

AbstractWhite matter damage may play an important role in the pathogenesis of vascular dementia. White matter abnormalities are easily visualized as white matter high‐intensity lesions (WML) on T2‐weighted magnetic resonance images. The extent of WML may be an indicator of cognitive impairment, in particular, impairment related to frontal lobe dysfunction. However, it is unclear whether the extent of WML is an independent predictor of cognitive impairment. In patients with extensive WML, atrophy of the corpus callosum may be an important predictor of global cognitive impairment. We investigated the relationship between the extent of WML and callosal size with cognitive function in patients who had been diagnosed with lacunar stroke or no specific neurological disease. Multivariate analysis showed that only callosal size and age were significant independent predictors of mini‐mental state examination scores (a measure of global cognitive function), whereas only the extent of WML was an independent predictor of the score on the verbal fluency task (a measure of frontal lobe function). Callosal atrophy may be an important predictor of global cognitive impairment in patients with WML, whereas the extent of WML per se may be related to impairment of frontal lobe function independent of callosal atrophy. White matter high‐intensity lesions with callosal atrophy may indicate a severe form of white matter damage with axonal loss, the degree of which may determine the severity of global cognitive impairment. Our longitudinal study revealed an association between progression of WML and vascular risk factor status during follow up in patients with initially mild WML. Early detection of WML without callosal atrophy at a stage of subtle cognitive impairment and slowing the progression of WML to a severe form with callosal atrophy might prevent the development of dementia.
Prevention and early intervention for vascular dementia in community dwelling elderly: Findings from the Nakayama study
Authors: Ikeda Manabu 
Published: May 2003

AbstractCerebrovascular disease (CVD) may be the single most common risk factor for age‐associated dementia (in particular for vascular dementia (VaD)), and there is definite potential for prevention and treatment of CVD. After one of the most comprehensive and precise type‐specific prevalence surveys of dementia (first Nakayama study), we have continued the preventive and early interventional approaches to CVD and VaD, including treatment of cardiovascular risk factors. In this cohort study, 88% of patients with ‘vascular cognitive impairment without dementia’, who were alive at 3‐years follow up, were still diagnosed with ‘vascular cognitive impairment without dementia’ and only 12% progressed to dementia. Compared with the results of previous studies, active control of risk factors and prevention of recurrent stroke may reduce the incidence of dementia and slow the progression of cognitive impairment in patients with ‘vascular cognitive impairment without dementia’.
Effects of low‐dose quetiapine on psychotic symptoms in elderly patients with physical illnesses: Report of eight cases
Authors: Hattori Hideyuki , Matsumoto Masayuki , Morimoto Shigeto , Iwai Kunimitu , Tsuchiya Hiroshi , Miyauchi Eiji , Takasaki Mikihiro , Nakahashi Tsuyoshi , Okaishi Kohya , Murai Hiroshi , Nishimura Yukiharu , Owari Yuhki , Nomura Kohji , Kato Shozaburo , Kong Ling Yu 
Published: May 2003

AbstractQuetiapine, which is a new atypical antipsychotic agent, was administered at low doses (25–50 mg/day) for psychotic symptoms in eight elderly patients with physical illnesses. Delirium and hallucination were alleviated by the administration of low doses of quetiapine, and the cause–effect relationship between the administration and alleviation of symptoms was evident, particularly in one patient with delirium, because delirium was alleviated after administration began, was exacerbated after discontinuation of quetiapine, and was alleviated again after administration was resumed. Little improvement was observed in delusions or mood disorders. None of the patients showed exacerbation of physical symptoms or abnormalities in clinical laboratory tests. The results of this study suggest that quetiapine might be effective in reducing delirium and hallucination that often accompany physical illness in elderly people and could be used without adverse effects.
Involvement of Rho‐associated kinase in neurite sprouting and amyloid beta production of rat cortical neurons cultured in insulin‐free medium
Authors: Matsumoto Naohiko , Nakamura Yu , Kashiwagi Yujiro , Hashimoto Ryota , Kudo Takashi , Tanaka Toshihisa , Shinosaki Kazuhiro , Takeda Masatoshi 
Published: May 2003

AbstractBackground: Abnormal sprouting of neurites is one of the neuropathological features of Alzheimer's disease. The mechanism of neurite sprouting of cultured neurons remains unknown. Among small guanosine triphosphate binding proteins, participation of the Rho family has been speculated.Methods: The involvement of Rho‐associated kinase in neurite sprouting and in amyloid beta (Αβ) production was investigated in primary cultured rat cortical neurons using morphometric analysis, immunohistochemistry and ELISA assay.Results: In a serum‐free medium, Y‐27632, a Rho‐associated kinase specific inhibitor, was found on the neurite outgrowth; however, there was no effect of Y‐27632 on Neurobasal/B27. A custom medium without insulin was prepared because insulin potentially influences neurite formation. In the insulin‐free medium, 10 µmol/L Y‐27632 appeared to promote neurite outgrowth, showing significant increases in neurite length and in the number of neurite terminals. Y‐27632 generated abnormal neurites, which were positively stained by both MAP2 and neurofilament‐L. Furthermore, the effect of Y‐27632 on Αβ production in primary cultured rat cortical neurons was investigated. Inhibition of Rho‐associated kinase increased the ratio of Αβ 42 /40+42.Conclusion: Our findings indicated that Rho‐associated kinase might be involved not only in neurite sprouting, but also in Αβ production in primary cultured neurons. Considering these two effects, inhibition of Rho‐associated kinase activity might be involved in the pathology of Alzheimer's disease.
Neurophysiological evaluation of late paraphrenia: Comparison with chronic schizophrenia and dementia of the Alzheimer type
Authors: Taguchi Satoki , Fujimoto Osamu , Takamori Nobutaka , Hanatani Takashi , Sumi Noriaki , Nan’no Hisashige , Takeda Masatoshi 
Published: May 2003

AbstractBackground: Late paraphrenia (LP) is a clinical entity first proposed by Roth in 1955. Recently, neuroimaging studies have described the organic changes in the brain that are associated with LP. We performed a neurophysiological study on patients with LP, chronic schizophrenics and patients with dementia of the Alzheimer type (DAT) to examine the cognitive function of patients with LP and to differentiate LP patients from these other groups.Methods: We investigated somatosensory‐evoked response (SER), contingent negative variation (CNV) and P300 in 30 LP patients, 22 chronic schizophrenics and 31 patients with DAT. Thirty‐four age‐matched healthy volunteers served as a control group. SER was performed by applying a mechanical stimulus to the right or left palm. CNV was performed by presenting a clicking sound (S1) and a flash of light (S2) to the subjects, with an interval between S1 and S2 of 2 s. P300 was performed using an auditory oddball paradigm.Results: The mean N3 peak latency of SER was significantly prolonged in patients with LP and in patients with DAT, compared with the control group. The mean CNV amplitude was significantly decreased in schizophrenics compared with the control group, but it did not decrease in patients with LP. The mean N200 and P300 latencies were significantly prolonged in patients with DAT compared with the control group, LP patients and schizophrenics, but the latencies of patients with LP were not prolonged compared with the control group.Conclusion: Based on these results, we propose that patients with LP have impaired cerebral reactivity to the stimulus, but their attention, motivation, recognition and differentiation are relatively intact. The present findings are consistent with former investigations, indicating that patients with LP are less likely to show negative symptoms, such as personality deterioration, and more likely to show organic changes in the brain relative to schizophrenics arising in early life.
Center of Excellence for Headache Care: Group Model at Kaiser Permanente
Authors: Blumenfeld Andrew , Tischio Marie 
Published: May 2003

Objective.—To evaluate the effectiveness of a disease management model for primary headache by: (1) assessing improvement in patients' quality of life, (2) decreasing headache‐related visits to primary care and emergency departments, and (3) maintaining high levels of patient and physician satisfaction.Background.—Patients with headache regularly seek health care but, in general, are dissatisfied with the care they receive. Patients with primary headaches utilize resources and cost health plans more than patients with other chronic diseases. Primary care visits are time restricted, prohibiting adequate headache evaluation and management. Practice guidelines are inconsistently followed, and access to headache specialists is limited. This headache management program implemented an alternative means of delivering care to manage large volumes of patients with headache. A multidisciplinary team approach coordinated by a neurologist, utilizing education and a nurse practitioner as the main provider of care, was the central process of the program.Methods.—This was a pilot study involving a prospective cohort with defined outcome measures. Inclusion criteria were adult patients with primary headaches. Patients initially attended an educational session instructed by a neurologist and a nurse practitioner. The patient was subsequently evaluated by the nurse practitioner who developed and coordinated a comprehensive individual treatment plan. The Migraine‐Specific Quality of Life and the Medical Outcomes Study 36‐Item Short Form Questionnaires were completed at baseline, at follow‐up visits, and 6 months after completion of the program. Subjective patient assessment of improvement in their headaches, chart review for tabulation of headache‐related visits, and primary care physician satisfaction surveys were measured.Results.—Both the Migraine‐Specific questionnaire and the Short Form‐36 measurements demonstrated a statistically significant improvement at 8 weeks, and this was maintained for 6 months after completing the program. At completion of the program, 92% of patients reported subjective improvement. Patient visits for headaches to primary care and emergency departments showed a significant decrease. High levels of satisfaction for primary care physicians were achieved.Conclusions.—A disease management model using a multidisciplinary team improved individualized patient care. This model increased patient/provider rapport and communication through an educational class. It empowered the patient to take control of their health care by utilizing shared decision making. Patient satisfaction improved and overall health care utilization was reduced.