bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneity of astroglia cultured from adult human temporal lobe
Authors: Davies David L. , Niesman Ingrid R. , Boop Frederick A. , Phelan Kevin D. 
Published: July 2002

AbstractThis study characterized the morphological and electrophysiological diversity of astroglia cultured from adult human cerebral temporal lobe, and explored the influence of the cytokine interleukin‐1β on these cells. The cultures contained astroglia positive for glial fibrillary acidic protein which were flat, bipolar or multipolar in shape and variable in size. A subpopulation of the bipolar and multipolar cells was positive for S100 protein. The most striking feature of these cultures was the presence of glia with long (600 μm) processes with few branches or only terminal branches. Patch clamp recordings of the non‐stellate process bearing cells revealed prominent inward Na+ and transient and sustained outward K+ conductances. Distinct differences in the relative proportion of these conductances were evident among cells but did not appear to be correlated with cell morphology. Treatment of cultures with interleukin‐1β for 96 h did not change total protein content, but increased the content of S100β protein and decreased the content of glial fibrillary acidic protein. The findings indicate that cultures of adult human cerebrum contain subpopulations of morphologically and electrophysiologically pleomorphic glial fibrillary acidic protein positive astroglia, exhibit increased levels of the neurotrophic factor S100β when exposed to interleukin‐1β, and may serve as a useful model for investigation of glial involvement in neuropathology.
Haemodynamic stability during moderate hypotensive anaesthesia for spinal surgery. A comparison between desflurane and isoflurane
Authors: Beaussier M. , Paugam C. , Deriaz H. , Mestari M. , Chandon M. , Sautet A. , Lienhart A. 
Published: July 2002

Background: The aim of this study was to compare desflurane and isoflurane for spinal procedures requiring moderate levels of controlled arterial hypotension, when these agents were administered via a semi‐closed circuit at 1 l min−1 fresh gas flow.Methods: After ethics committee approval and written informed consent, 20 ASA I or II patients were randomly allocated to receive either desflurane (n=10) or isoflurane (n=10), in O2/N2O (1:1) for maintenance of anaesthesia. Induction of anaesthesia, fentanyl dosing and volume loading were standardized. Blood pressure was invasively monitored and maintained within a target systolic blood pressure (SBP) range of 80 to 100 mmHg during the study period. Results were presented as medians and interquartiles, and non‐parametric statistical methods were used.Results: Patient demographic data, SBP and heart rate prior to surgery, and duration of the procedure were similar between the two groups. During the study period, tighter arterial blood pressure control was maintained with desflurane as compared with isoflurane. SBP was 21.2% (9.5–41.7) of time outside the range 80–100 mmHg with isoflurane and 5.1% (0.6–10.3) with desflurane (P<0.01).Conclusions: Desflurane, administered via a semi‐closed circuit at 1 l min−1 fresh gas flow, maintained better haemodynamic stability in spinal surgery requiring moderate arterial hypotension than isoflurane.
Chronic Daily Headache in the Posttrauma Syndrome: Relation to Extent of Head Injury
Authors: Couch James R. , Bearss Candace 
Published: July 2002

Objective.—To evaluate the occurrence of continued intermittent headache and chronic daily headache in patients with head injury and the relationship between severity of the headache problem and intensity of the head injury.Background.—In the majority of patients with posttraumatic headache, the condition is self‐limited, but a minority of patients may develop persistent headaches. The features of posttraumatic headache may vary, but the most distressing type is the chronic daily headache. This study evaluates occurrence of chronic daily headache in relation to the intensity of head injury.Methods.—All patients with head injury who were seen by the senior author (J.R.C.) in the Southern Illinois University Medical School (SIUMS) Neurology Clinic between 1980 and 1991 were identified from the SIUMS headache registry. Data on headache status before and after head injury was obtained, and patients with more than one headache per week before head injury were excluded. Each patient's headache status at the time of the clinic visit was classified as chronic daily headache (headache occurring at least 5 of 7 days for 6 months), intermittent migraine, or no headache. Head injury severity was graded by duration of loss of consciousness or amnesia as minimal (less than 5 minutes), mild (5 to 60 minutes), moderate (1 to 24 hours), or severe (more than 24 hours).Results.—There was an inverse relation between extent of head injury and occurrence of chronic daily headache. For minimal head injury (n = 54), 80% had chronic daily headache, and 11% had no headache, while for moderate/severe head injury (n = 23), only 27% had chronic daily headache, and 68% had no headache (P<.001, χ2).Conclusion.—This study suggests that the risk of developing posttraumatic chronic daily headache is greater for less severe head injury compared with moderate/severe head injury. The reason for this relation is unclear.
Medical Care for Nursing Home Residents: Differences by Dementia Status
Authors: Burton Lynda C. , German Pearl S. , Gruber‐Baldini Ann L. , Hebel J. Richard , Zimmerman Sheryl , Magaziner Jay , For The Epidemiology of Dementia in Nursing Homes Research G  
Published: July 2002

OBJECTIVE: To understand the use of medical services by nursing home residents.DESIGN: Descriptive, longitudinal study comparing medical service use of residents by dementia status and describing the use of medical services following detection of fever or infection.SETTING: Fifty‐nine randomly selected nursing homes in Maryland from 1992 to 1995.PARTICIPANTS: 2153 residents admitted to one of 59 randomly selected nursing homes.MEASUREMENT: A panel of psychiatrists and neurologists ascertained dementia based on review of medical records, interview data with significant others and nursing staff, and results of a cognitive exam. Medical service use was abstracted from medical records.BACKGROUND: Understanding the use of medical services by nursing home residents as distinct from services provided by the nursing home is important, particularly as new medical care models are tested. This study compares the medical service use of residents by dementia status and describes the use of medical services following detection of fever or infection.RESULTS: Residents with dementia compared with those without dementia had lower annual rates of physician visits (10.2 vs 12.7, P < .001) and hospitalizations (0.9 vs 1.2, P < .001), virtually the same rate of emergency department visits, and similar lengths of stay in the hospital. Subsequent to infection, a lower proportion of residents with dementia had either a physician visit, an emergency department visit, or a hospital admission compared with residents without dementia (27.2% vs 32.2%, P < .001). In 87% of infections, an antibiotic was used, implying meaningful contact with a physician. Residents with dementia compared with those without dementia had fewer physician visits subsequent to fevers (20.6% vs 29.9%, P < .001) and infections (21.8% vs 27.5%, P < .001).CONCLUSIONS: The association of less medical service use by individuals with dementia compared with those without dementia may reflect differences in health status or implicit end‐of‐life decision‐making and a proclivity toward less‐aggressive treatment for these individuals.
The Differential Influence of Distinct Clusters of Psychiatric Symptoms, as Assessed by the General Health Questionnaire, on Cause of Death in Older Persons Living in a Rural Community of Japan
Authors: Yasuda Nobufumi , Mino Yoshio , Koda Shigeki , Ohara Hiroshi 
Published: July 2002

OBJECTIVES: To examine the influence of distinct clusters of psychiatric symptoms on subsequent cause‐specific mortality in older persons living in the community.DESIGN: A prospective cohort study over 7.5 years.SETTING: Otsuki‐town, Kochi prefecture, Japan.PARTICIPANTS: Nine hundred eighty community‐dwelling persons, aged 65 to 84 in 1991.MEASUREMENTS: Psychiatric symptoms at baseline were measured using the 30‐item version of the General Health Questionnaire (GHQ‐30). A factor analysis was performed on the responses of all 980 subjects. The relationships between subscale scores on the identified factors and causes of deaths occurring over 7.5 years in 817 respondents with no physical disability at baseline were assessed using a proportional hazards model adjusted for age, gender, chronic conditions under treatment, regular physical activity, and availability of close or casual neighbors.RESULTS: The factor analysis identified three clusters of psychiatric symptoms: depression, apathy/anergia, and anxiety. In the proportional hazards model, which included three GHQ subscales depicting these factors simultaneously, the depression subscale was associated with increased mortality from cerebrovascular disease (multivariate adjusted hazard ratio per unit increase in the standard score on the depression subscale = 2.04, 95% confidence interval (CI) = 1.17–3.55), and the apathy/anergia subscale was associated with increased mortality from noncancer and noncardiovascular causes (multivariate adjusted hazard ratio per unit increase in the standard score on the apathy/anergia subscale = 1.71, 95% CI = 1.25–2.34). The anxiety subscale was not associated with any cause of death.CONCLUSION: Depressive symptoms and symptoms indicating apathy/anergia have differential influences on subsequent causes of death in older persons living in the community. Identification of specific psychiatric symptom clusters may contribute to the prevention of deaths from specific causes in older populations.
Severe Dementia and Adverse Outcomes of Nursing Home‐Acquired Pneumonia: Evidence for Mediation by Functional and Pathophysiological Decline
Authors: Van Der Steen Jenny T. , Ooms Marcel E. , Mehr David R. , Van Der Wal Gerrit , Ribbe Miel W. 
Published: July 2002

OBJECTIVES:To assess whether the severity of dementia is related to unfavorable outcomes of nursing home‐acquired pneumonia and how this relationship is mediated.DESIGN:Prospective cohort study.SETTING:Psychogeriatric wards of 61 nursing homes in the Netherlands.MEASUREMENTS:Dementia severity and the possible mediators swallowing disturbance, aspiration, insufficient food intake, weight loss, and dehydration were measured and related to the following outcomes: death (rate), cure rate, and increase in discomfort at the onset of pneumonia.PARTICIPANTS:Demented patients (n = 374) treated with antibiotics for pneumonia.RESULTS:Dementia severity was independently related to death rate within the first week after pneumonia (hazard rate ratio = 3.0 for the most severely demented quartile versus the least demented quartile, 95% confidence interval (CI) = 1.1–8.3) and to 3‐month mortality (odds ratio (OR) = 2.5, 95% CI = 1.1–5.4). The latter relation was in part mediated by aspiration and weight loss (OR dementia severity adjusted for these mediators declined from 2.5 to 1.9, 95% CI = 0.8–4.3). Dementia severity was not related to cure rate within 2 weeks nor to an increase in discomfort after 3 days compared with before the pneumonia.CONCLUSION:The functional and pathophysiological consequences of progressive dementia account in part for increased 3‐month mortality after pneumonia. Mid‐term mortality is expected to be high only in the most severely demented patients and in less severely demented patients who aspirated or who lost weight. Implications for end‐of‐life decision‐making and effectiveness of preventive and curative interventions are discussed. J Am Geriatr Soc 50:439–448, 2002.
Serum Albumin Concentration and Clinical Assessments of Nutritional Status in Hospitalized Older People: Different Sides of Different Coins?
Authors: Covinsky Kenneth E. , Covinsky Michael H. , Palmer Robert M. , Sehgal Ashwini R. 
Published: July 2002

OBJECTIVES:Malnutrition is common in hospitalized older people, and some have advocated routine nutritional screening. Serum albumin and clinically based measures such as the Subjective Global Assessment (SGA) are two potential methods of assessing nutritional status in hospitalized older people. Although both measures are strongly associated with prognosis, it is not clear whether they measure similar or different clinical constructs. Our goal was to assess the degree of clinical concordance between these measures.DESIGN:Cross‐sectional study.SETTING:The inpatient medical service of a university teaching hospital.PARTICIPANTS:Three hundred eleven older (aged ≥70) patients.MEASUREMENTS:We independently measured serum albumin and performed the SGA on 311 older medical patients (aged ≥70) shortly after hospital admission. The SGA classified patients as well nourished, moderately malnourished (generally 5% weight loss with mild examination findings), or severely malnourished (generally>10% weight loss with marked findings) based on findings from a directed history and examination. We compared the distribution of clinical rating in patients with differing albumin levels and examined diagnostic test characteristics of albumin as a predictor of malnutrition as diagnosed on clinical examination.RESULTS:The mean age of subjects was 79.9; 64% were women, 42% were African American. Discordance between albumin and the SGA was common. For example, 38% of patients with albumin levels of 4.0 g/dL or higher were at least moderately malnourished on the SGA, whereas 28% of patients with albumin levels lower than 3.0 g/dL were rated as well nourished. No choice of albumin level was associated with simultaneously acceptable sensitivity and specificity as a predictor of SGA ratings. The area under the receiver operating characteristic curve for albumin level as a predictor of SGA rating was 0.58, suggesting that the ability of either measure to predict the other measure is only marginally better than chance.CONCLUSIONS:Albumin levels and clinical assessments, two possible measures of nutritional status in hospitalized older people, are often discordant. To some extent, this reflects limitations in both measures as markers of nutritional status. However, it also demonstrates that, in this population, albumin and clinical assessments of nutritional status reflect fundamentally different clinical processes. J Am Geriatr Soc 50:631–637, 2002.
Nonadiabatic effects in the photodissociation of H2S in the first absorption band: An ab initio study
Authors: Heumann Bernd , Weide Klaus , Düren Rudolf , Schinke Reinhard 
Published: July 2002

The photodissociation of H2S through excitation in the first absorption band (λ≊195 nm) is investigated by means of extensive ab initio calculations. Employing the MRD-CI method we calculate the potential energy surfaces for the lowest two electronic states of 1A″ symmetry varying both HS bond distances as well as the HSH bending angle. (In the C2v point group these states have electronic symmetry 1B1 and 1A2, respectively.) The lower adiabatic potential energy surface is dissociative when one H atom is pulled away whereas the upper one is binding. For the equilibrium angle of 92° in the electronic ground state they have two conical intersections, one occurring near the Franck–Condon point. Because of the very small energy separation between these two states nonadiabatic coupling induced by the kinetic energy operator in the nuclear degrees of freedom are substantial and must be incorporated in order to describe the absorption and subsequent dissociation process in a realistic way. In the present work we treat the coupling between the two electronic states in a diabatic representation extracting the coordinate-dependent mixing angle from the CI coefficients of the electronic wave functions. The nuclear motion is treated in three dimensions in an exact quantum mechanical approach by propagation of a two-component time-dependent wave packet. The calculated absorption spectra for H2S and D2S satisfactorily agree with the measured spectra. In particular, the calculations reproduce the diffuse structures with energy spacing of about 1200 and 850 cm−1 for H2S and D2S, respectively. Furthermore, the calculated rotational- and vibrational-state distributions of the HS and DS fragments reproduce recent measurements in a convincing way. The photodissociation of H2S is a prototype for very fast electronic predissociation. The photon preferentially excites the binding (diabatic) state. This state, however, is quickly depleted by strong coupling to the dissociative (diabatic) state with the complex finally breaking up into products H and HS. The electronic quenching takes place on the time scale of one internal vibrational period only.
Our calculations unambiguously confirm that the diffuse structures superimposed to the broad background are caused by symmetric stretch motion—in the binding state—and not by activity in the bending mode as originally assumed.
Probing dynamics in the Franck–Condon and exit channel regions of dissociating H2S: Emission spectra upon tunable excitation from 199–203 nm
Authors: Browning P. W. , Jensen E. , Waschewsky G. C. G. , Tate M. R. , Butler L. J. , Hessler J. P. 
Published: July 2002

This study uses emission spectroscopy of H2S at excitation energies near 200 nm to probe the dissociation dynamics from a conical intersection in the Franck–Condon region to the H+SH product exit channel. Photoexcitation accesses these coupled surfaces near the transition state region of the lower adiabat, a potential surface for the excited state H+SH→HS+H reaction. Excitation wavelengths from 199–203 nm tune through the first of the resonances in the absorption spectrum assigned to recurrences in the motion along the symmetric stretch orthogonal to the reaction coordinate and also access energies just above and at the conical intersection. We disperse the emission from the dissociating molecules at each of five excitation wavelengths in this region to probe several features of the reaction dynamics on the coupled potential energy surfaces. The resulting emission spectra cover the range of final vibrational eigenstates from 500 to 11 000 cm−1 above the initial ground vibrational state for all five excitation wavelengths, and go out to 16 500 cm−1 for the 199 and 201 nm excitation wavelengths. The resulting spectra, when considered in conjunction with recent scattering calculations by Heumann and Schinke on ab initio potential energy surfaces for this system, evidence a progression of emission features to low vibrational eigenstates in the SH stretch that result from coupling of the nuclear motion from the bound to the dissociative region of the potential energy surfaces.
This emission, into local mode eigenstates such as 00+1, 11+0, 11+1, 21+0, 21+1, evidences the antisymmetric dissociative motion and bending induced near the conical intersection, and dominates the spectrum at excitation wavelengths only near 200 nm. We analyze the excitation wavelength dependence of these features and also of the n0+0 progression for n≥4, which reflect the exit channel dynamics. The excitation wavelength dependence shows that while the emission spectra do not reveal any dynamics unique to scattering states that access a symmetric stretch resonance in the Franck–Condon region, they do reveal the energy location of and the dynamics at the conical intersection. A reanalysis of other workers’ measurements of the SH product vibrational state distribution shows that v=0 products are strongly favored at excitation wavelengths near the conical intersection.
17O hyperfine and quadrupole interactions for water ligands in frozen solutions of high spin Mn2+
Authors: Tan Xiaoling , Bernardo Marcelino , Thomann Hans , Scholes Charles P. 
Published: July 2002

The magnetic couplings of 17O in H217O coordinated to high spin Mn2+ in a frozen aqueous solution were determined using the complementary magnetic resonance techniques of pulsed and continuous wave (cw) ENDOR (electron nuclear double resonance), ESEEM (electron spin echo envelope modulation), and PFSEPR [pulse field sweep electron paramagnetic resonance (EPR)]. Several complications arise from the high electron spin multiplicity of the d5, Mn2+ ion and the high nuclear spin multiplicity, I=5/2, of the 17O nucleus. At the applied magnetic field strengths in 9 GHz EPR studies, the zero-field splitting of the S=5/2 Mn2+ ion in aqueous frozen solution is small relative to the electron spin Zeeman interaction so that the MS=±1/2,±3/2,±5/2 electron spin states all contribute to the ENDOR spectrum.
This results in a complex spectrum in which the 17O ENDOR powder pattern arising from the MS=±1/2 manifolds are separately resolved but the powder patterns from the MS=±3/2,±5/2 manifolds overlap the multiple 1H ENDOR lines arising from all six MS manifolds [X. Tan, M. Bernardo, H. Thomann, and C. P. Scholes, J. Chem. Phys. 98, 5147 (1993)]. Given this complexity, a combination of complementary spectroscopic techniques and numerical simulations are used to deconvolute the overlapping spectra and to assign the spectral lines. The ENDOR spectra provided an experimental description of H217O hyperfine couplings to high spin Mn2+ in a frozen solution. The ESEEM results are consistent with the first-order assignments of the ENDOR lines and demonstrate the feasibility of ESEEM measurements of 17O ligand hyperfine couplings to Mn2+. Simulations of the 17O ENDOR hyperfine patterns of aqueous frozen solutions of Mn2+, especially those near 20 MHz, indicated an A-tensor anisotropy of A⊥=−6.5±0.5 MHz and A∥=−9.5±0.5 MHz, consistent with couplings observed by single crystal ENDOR of H217O ligated to Mn2+ doped in [LaMg(NO2)12⋅24(H2O)]. More detailed simulations of the ENDOR pattern below 10 MHz indicated the need for quadrupole couplings consistent with those measured by single crystal ENDOR and with those determined by gas phase measurements on H17OD. Simulations of the ENDOR spectra recorded by the cw and pulsed techniques have delineated important features of the techniques which must be taken into account for a quantitative analysis of the ENDOR amplitudes. It is expected that the general ENDOR conditions employed and the theory developed will be useful in frozen solution studies of 17O involved as a ligand to Mn2+ in enzymes.