bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular mechanisms mediating pathological plasticity in Huntington's disease and Alzheimer's disease
Authors: Spires Tara L. , Hannan Anthony J. 
Published: January 2007

AbstractNeurodegenerative diseases such as Huntington's disease and Alzheimer's disease, although very different in etiology, share common degenerative processes. These include neuronal dysfunction, decreased neural connectivity, and disruption of cellular plasticity. Understanding the molecular mechanisms underlying the neural plasticity deficits in these devastating conditions may lead the way toward new therapeutic targets, both disease‐specific and more generalized, which can ameliorate degenerative cognitive deficits. Furthermore, investigations of ‘pathological plasticity’ in these diseases lend insight into normal brain function. This review will present evidence for altered plasticity in Huntington's and Alzheimer's diseases, relate these findings to symptomatology, and review possible causes and commonalities.
Anti‐homeostatic synaptic plasticity of glycine receptor function after chronic strychnine in developing cultured mouse spinal neurons
Authors: Carrasco M. A. , Castro P. A. , Sepulveda F. J. , Cuevas M. , Tapia J. C. , Izaurieta P. , Zundert B. van , Aguayo L. G. 
Published: January 2007

AbstractIn this study, we describe a novel form of anti‐homeostatic plasticity produced after culturing spinal neurons with strychnine, but not bicuculline or 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione (CNQX). Strychnine caused a large increase in network excitability, detected as spontaneous synaptic currents and calcium transients. The calcium transients were associated with action potential firing and activation of γ‐aminobutyric acid (GABAA) and alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptors as they were blocked by tetrodotoxin (TTX), bicuculline, and CNQX. After chronic blockade of glycine receptors (GlyRs), the frequency of synaptic transmission showed a significant enhancement demonstrating the phenomenon of anti‐homeostatic plasticity. Spontaneous inhibitory glycinergic currents in treated cells showed a fourfold increase in frequency (from 0.55 to 2.4 Hz) and a 184% increase in average peak amplitude compared with control. Furthermore, the augmentation in excitability accelerated the decay time constant of miniature inhibitory post‐synaptic currents. Strychnine caused an increase in GlyR current density, without changes in the apparent affinity. These findings support the idea of a post‐synaptic action that partly explains the increase in synaptic transmission. This phenomenon of synaptic plasticity was blocked by TTX, an antibody against brain‐derived neurotrophic factor (BDNF) and K252a suggesting the involvement of the neuronal activity‐dependent BDNF‐TrkB signaling pathway. These results show that the properties of GlyRs are regulated by the degree of neuronal activity in the developing network.
Pyruvate modifies glycolytic and oxidative metabolism of rat embryonic spinal cord astrocyte cell lines and prevents their spontaneous transformation
Authors: Rouleau Caroline , Rakotoarivelo Clovis , Petite Didier , Lambert Karen , Fabre Christine , Bonardet Andrée , Mercier Jacques , Baldet Pierre , Privat Alain , Langley Keith , Mersel Marcel 
Published: January 2007

AbstractThis study aimed to provide detailed data on mitochondrial respiration of normal astrocyte cell lines derived from rat embryonic spinal cord. Astrocytes in early passages (EP), cultured without pyruvate for more than 35 passages, defined here as late passages (LP), undergo spontaneous transformation. To study initial steps in cell transformation, EP data were compared with those of LP cells. LP cells had reduced glycolysis, fewer mitochondria and extremely low oxidative rates, resulting from a dysfunction of complexes I and II + III of the respiratory chain. Treatment of EP cells with pyruvate until they were, by definition, LP cultures prevented transformation of these cells. Pyruvate‐treated EP cells had more mitochondria than normal cells but slightly lower respiratory rates. The increase of mitochondrial content thus appears to act as a compensatory effect to maintain oxidative phosphorylation in these LP ‘non‐transformed’ cells, in which mitochondrial function is reduced. However, pyruvate treatment of transformed LP cells during additional passages did not significantly restore their oxidative metabolism. These data highlight changes accompanying spontaneous astrocyte transformation and suggest potential targets for the control of astrocyte proliferation and reaction to various insults to the central nervous system.
The vesicular monoamine transporter 2 contains trafficking signals in both its N‐glycosylation and C‐terminal domains
Authors: Yao Jia , Hersh Louis B. 
Published: January 2007

AbstractThe vesicular acetylcholine transporter (VAChT) and the vesicular monoamine transporter (VMAT) belong to the same transporter family that packages acetylcholine into synaptic vesicles (SVs) and biogenic amines into large dense core vesicles (LDCVs) and/or SVs, respectively. These transporters share similarities in sequence and structure with their N‐ and C‐terminal domains located in the cytoplasm. When expressed in PC12 cells, VMAT2 localizes to LDCV, whereas VAChT is found mainly on synaptic‐like microvesicles. Previous studies have shown that the cytoplasmic C‐terminal domain of VAChT contains signals targeting this transporter to SVs. However, the targeting signals for VMAT have not been completely elucidated. To identify signals targeting VMAT2 to LDCV, the subcellular localization of VMAT2–VAChT chimeras was analyzed in PC12 cells. Chimeras having either the N‐terminal region through transmembrane domain 2 of VMAT2 or the C‐terminal domain of VMAT2 do not traffic to LDCV efficiently. In contrast, chimeras having both of these regions, or the luminal glycosylated loop in conjunction with transmembrane domains 1 and 2 and the C‐terminal domain of VMAT2, traffic to LDCV. Treatment of PC12 cells with 1‐deoxymannojirimycin, a specific alpha‐mannosidase I inhibitor, causes VMAT2 to localize to synaptic‐like microvesicles. The results indicate that both mature N‐linked glycosylation and the C‐terminus are important for proper trafficking of VMAT2 and that the locations of trafficking signals in VMAT2 and VAChT are surprisingly different.
Tubulin cofactor B plays a role in the neuronal growth cone
Authors: Lopez‐Fanarraga M. , Carranza G. , Bellido J. , Kortazar D. , Villegas J. C. , Zabala J. C. 
Published: January 2007

AbstractTubulin cofactors, initially identified as α‐, β‐tubulin folding proteins, are now believed to participate in the complex tubulin biogenesis and degradation routes, and thus to contribute to microtubule functional diversity and dynamics. However, a concrete role of tubulin cofactor B (TBCB) remains to be elucidated because this protein is not required for tubulin biogenesis, and it is apparently not essential for life in any of the organisms studied. In agreement with these data, here we show that TBCB localizes at the transition zone of the growth cones of growing neurites during neurogenesis where it plays a role in microtubule dynamics and plasticity. Gene silencing by means of small interfering RNA segments revealed that TBCB knockdown enhances axonal growth. In contrast, excess TBCB, a feature of giant axonal neuropathy, leads to microtubule depolymerization, growth cone retraction, and axonal damage followed by neuronal degeneration. These results provide an important insight into the understanding of the controlling mechanisms of growth cone microtubule dynamics.
A role of local signalling in the establishment and maintenance of the asymmetrical architecture of a neuron
Authors: Hur Eun‐Mi , Kim Kyong‐Tai 
Published: January 2007

AbstractSignificant progress has been made in the identification of intrinsic and extrinsic factors involved in the development of nervous system. It is remarkable that the establishment and maintenance of the asymmetrical architecture of a neuron is coordinated by a limited repertoire of signalling machineries. However, the details of signalling mechanisms responsible for creating specificity and diversity required for proper development of the nervous system remain largely to be investigated. An emerging body of evidence suggests that specificity and diversity can be achieved by differential regulation of signalling components at distinct subcelluar localizations. Many aspects of neuronal polarization and morphogenesis are attributed to localized signalling. Further diversity and specificity of receptor signalling can be achieved by the regulation of molecules outside the cell. Recent evidence suggests that extracellular matrix molecules are essential extrinsic cues that function to foster the growth of neurons. Therefore, it is important to understand where the signalling machineries are activated and how they are combined with other factors in order to understand the molecular mechanism underlying neuronal development.
Assessment of blood pressure in cats presented with urethral obstruction
Authors: Malouin Annie , Milligan James A. , Drobatz Kenneth J. 
Published: January 2007

AbstractObjective:To determine the arterial blood pressure at presentation in male cats with acute urethral obstruction, and to determine whether there was any correlation between these measurements and concurrent metabolic abnormalities.Design:Prospective, single cohort, observational study.Setting:Private, small animal, after‐hours emergency clinic.Animals:Twenty‐eight client‐owned male cats with acute urethral obstruction and no other known coexisting disease.Interventions:Indirect oscillometric blood pressure measurements obtained before blood sampling and treatment.Measurements and main results:Mean arterial blood pressure (MAP) measurements, physical examination parameters, serum blood urea nitrogen (BUN), creatinine, potassium, phosphorus, total calcium and magnesium concentration, venous pH, lead II electrocardiogram, and urine volume in bladder were evaluated. No cats were hypotensive at presentation; 71% (20/28) were normotensive (median MAP=100 mmHg, range 93–140 mmHg); and 29% (8/28) were hypertensive (median MAP=153 mmHg, range 145–176 mmHg). Compared with hypertensive cats, normotensive cats had significantly lower heart rates (P=0.0201) and lower calcium (P=0.0152). For all 28 cats, MAP correlated with serum potassium and total calcium (P=0.0033).Conclusions:Though potassium and total calcium were inversely and directly correlated respectively with blood pressure in cats with urethral obstruction, none of the cats were hypotensive on presentation. Normotension on admission does not support the absence of biochemical and physical abnormalities in obstructed cats.
The effects of ice‐water storage on blood gas and acid–base measurements
Authors: Rezende Marlis L. , Haskins Steve C. , Hopper Kate 
Published: January 2007

AbstractObjective: To determine the effects of storage of arterial and venous blood samples in ice water on blood gas and acid–base measurements.Design: Prospective, in vitro, laboratory study.Setting: School of veterinary medicine.Subjects: Six healthy dogs.Measurements and main results: Baseline measurements of partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), pH, hemoglobin concentration (tHb), oxyhemoglobin saturation, and oxygen content (ContO2) were made. Bicarbonate (HCO3) and standard base excess (SBE) were calculated. Arterial and venous blood samples were separated into 1 and 3 mL samples, anaerobically transferred into 3 mL plastic syringes, and stored in ice water for 6 hours. Measurements were repeated at 15, 30 minutes, and 1, 2, 4, and 6 hours after baseline measurements. Arterial (a) PO2 increased significantly from baseline after 30 minutes of storage in the 1 mL samples and after 2 hours in the 3 mL samples. Venous (v) PO2 was significantly increased from baseline after 4 hours in the 1 mL samples and after 6 hours in the 3 mL samples. The pHa significantly decreased after 2 hours of storage in the 1 mL samples and after 4 hours in the 3 mL samples. In both the 1 and 3 mL samples, pHv decreased significantly only after 6 hours. Neither the arterial nor the venous PCO2 values changed significantly in the 1 mL samples and increased only after 6 hours in the 3 mL samples. No significant changes in tHb, ContO2, SBE, or HCO3 were detected.Conclusions: The PO2 of arterial and venous blood increased significantly when samples were stored in plastic syringes in ice water. These increases are attributable to the diffusion of oxygen from and through the plastic of the syringe into the blood, which occurred at a rate that exceeded metabolic consumption of oxygen by the nucleated cells.
The Syphilis Elimination Project: Targeting the Hispanic Community of Baltimore City
Authors: Endyke‐Doran Cara , Gonzalez Rosa Maria , Trujillo Marangellie , Solera Angelo , Vigilance Pierre N. , Edwards Lori A. , Groves Sara L. 
Published: January 2007

ABSTRACT
Objective: The objective of the Syphilis Elimination Project was to decrease the incidence of syphilis in the Hispanic community of Baltimore City through a culturally appropriate health initiative.Design: Both qualitative and quantitative methods were used in the study design. Surveillance data were used to collect testing information. Comparisons at the start and end of the project measured change in individual knowledge about syphilis. Cross‐sectional data from interviews with business owners and qualitative comments from outreach workers evaluated perception of program effectiveness. The local health department collected surveillance data.Sample: A convenience sample of 63 Hispanic community members, 12 business owners/managers, and 8 outreach workers was utilized throughout the evaluation process.Intervention: The project was a culturally appropriate approach to health promotion with street and business outreach.Results: Post intervention there was a statistically significant increase in knowledge about syphilis within the Hispanic community and an increase in testing behaviors.Conclusions: The Syphilis Elimination Project was created in response to a marked increase in syphilis in Baltimore among the Hispanic population and a health disparity that existed within the city. It increased community members' knowledge of syphilis and positively influenced testing behaviors.
Improving the Selective Neonatal BCG Program
Authors: Wroe Abigail L. , McKeever Charmian , Thackray Sue , Bhan Angela 
Published: January 2007

ABSTRACT
Objectives: The aim of the work was to develop and implement an improved selective neonatal Bacille‐Calmette‐Guerin (BCG) vaccine program in which neonates are systematically assessed, and those identified as at “high risk of being exposed to tuberculosis” are given neonatal BCG.Design: Service models used in other parts of the country were assessed and their limitations and difficulties were carefully considered. Possible service models for local use were then considered. A selective neonatal BCG program involving universal neonatal screening was implemented.Sample: A program was implemented offering BCG to high‐risk neonates.Results: As has been the case with other health trusts, developing a new neonatal BCG service met with obstacles and hurdles. Means of overcoming some of the difficulties are presented. Preliminary findings regarding the service model, including neonatal BCG uptake rates, were positive.Conclusion: A successful neonatal BCG program was implemented.
A Relationship Power Scale for Female Adolescents: Preliminary Development and Psychometric Testing
Authors: Wang Ruey‐Hsia , Wang Hsiu‐Hung , Hsu Hsiu‐Yueh 
Published: January 2007

ABSTRACT
Objectives: To develop and test psychometric characteristics of the Relationship Power Scale (RPS), which can be used to explore the relationship power of female adolescents in heterosexual relationships.Methods: Cross‐sectional design. Female adolescents in Kaohsiung City, Taiwan, who had a steady relationship with a boyfriend at the time of the study were recruited as study subjects (n=414) to test validity and reliability of the RPS.Results: Confirmatory factor analysis revealed that a one‐factor model with correlated uniqueness among the positively worded items best fits the data. There were significantly different scores in 3 different response groups on 2 items regarding who (participants, both themselves and their boyfriends equally, or their boyfriends) had more power in the relationship, and who was more emotionally involved in the relationship for all subjects. For subjects having sex with their steady boyfriends, RPS scores significantly differ among the 3 different response groups on 2 items regarding who had more say about having sex, and who had more say about using condoms. Cronbach's α for the RPS was .69. Test‐retest reliability coefficients for the RPS were .83.Conclusions: The RPS exhibited acceptable reliability and validity. Further research is recommended to use the RPS in sex‐related behavior research among heterosexual female adolescents.
Does 8‐Foot Walk Time Predict Cognitive Decline in Older Mexicans Americans?
Authors: Alfaro‐Acha Ana , Al Snih Soham , Raji Mukaila A. , Markides Kyriakos S. , Ottenbacher Kenneth J. 
Published: January 2007

OBJECTIVES: To examine the association between 8‐foot time walk and change in cognitive function over time in older Mexican Americans.DESIGN: Data used are from the Hispanic Established Population for the Epidemiological Study of the Elderly (1993–2001).SETTING: Five southwestern states: Texas, New Mexico, Colorado, Arizona, and California.PARTICIPANTS: Two thousand seventy noninstitutionalized Mexican‐American men and women aged 65 and older who had a Mini‐Mental State Examination (MMSE) score of 21 or greater at baseline.MEASUREMENTS: Sociodemographic factors (age, sex, education, marital status), MMSE score, 8‐foot walk time, body mass index, medical conditions (stroke, heart attack, diabetes mellitus, depression, and hypertension), and near and distant visual impairment.RESULTS: Using general linear mixed models, it was found that subjects with the slowest 8‐foot walk time had a significantly greater rate of cognitive decline over 7 years than subjects with the fastest 8‐foot walk time. There was a significant 8‐foot walk time–by‐time interaction with MMSE scores. Subjects in the lowest 8‐foot walk time quartile had a greater cognitive decline over 7 years (estimate=−0.32, SE=0.08; P<.001) than those in the highest quartile. This association remained statistically significant after controlling for potential confounding factors.CONCLUSION: Slow 8‐foot walk time in older Mexican‐American adults without cognitive impairment at baseline was an independent predictor of MMSE score decline over a 7‐year period. Slow 8‐foot walk time may be an early marker for older adults in a predementia state who may benefit from early‐intervention programs to prevent or slow cognitive decline.
Anxiety Symptoms and Decline in Physical Function over 5 Years in the Health, Aging and Body Composition Study
Authors: Mehta Kala M. , Yaffe Kristine , Brenes Gretchen A. , Newman Anne B. , Shorr Ronald I. , Simonsick Eleanor M. , Ayonayon Hilsa N. , Rubin Susan M. , Covinsky Kenneth E. 
Published: January 2007

OBJECTIVES: To examine the relationship between anxiety and functional decline.DESIGN: A 5‐year longitudinal cohort study of well‐functioning adults.SETTING: The Health, Aging and Body Composition (Health ABC) Study.PARTICIPANTS: Two thousand nine hundred forty adults aged 70 to 79 (48% male, 41% black), initially free of self‐reported mobility difficulty.MEASUREMENTS: In 1997/98, presence of three anxiety symptoms (feeling fearful, tense or keyed up, or shaky or nervous) from the Hopkins Symptom Checklist were ascertained. Physical function was examined over 5 years using the Health ABC performance battery (continuous range 0–4) consisting of chair stands, usual and narrow course gait speed, and difficulty with standing balance and self‐reported mobility, defined as difficulty walking one‐quarter of a mile or difficulty climbing 10 steps.RESULTS: Participants with anxiety symptoms had similar baseline physical performance scores. After adjustment for potential confounders, subjects with anxiety symptoms had similar declines in physical performance over 5 years as participants without anxiety symptoms. Adults with anxiety symptoms were more likely to report incident mobility difficulty, with a hazard ratio of 1.4 (95% confidence interval=1.3–1.6), compared with adults without anxiety symptoms. These results persisted after adjustment for depressive symptoms, demographics, comorbidity, and use of antianxiety, depressant, and sedative hypnotic medications.CONCLUSION: Anxiety symptoms are not associated with declines in objectively measured physical performance over 5 years but are associated with declines in self‐reported functioning. Future studies are needed to determine why anxiety has a differential effect on performance‐based and self‐reported measures of functioning.
A Higher Dose of Vitamin D Reduces the Risk of Falls in Nursing Home Residents: A Randomized, Multiple‐Dose Study
Authors: Broe Kerry E. , Chen Tai C. , Weinberg Janice , Bischoff‐Ferrari Heike A. , Holick Michael F. , Kiel Douglas P. 
Published: January 2007

OBJECTIVES: To determine the effect of four vitamin D supplement doses on falls risk in elderly nursing home residents.DESIGN: Secondary data analysis of a previously conducted randomized clinical trial.SETTING: Seven hundred twenty‐five‐bed long‐term care facility.PARTICIPANTS: One hundred twenty‐four nursing home residents (average age 89).INTERVENTION: Participants were randomly assigned to receive one of four vitamin D supplement doses (200 IU, 400 IU, 600 IU, or 800 IU) or placebo daily for 5 months.MEASUREMENTS: Number of fallers and number of falls assessed using facility incident tracking database.RESULTS: Over the 5‐month study period, the proportion of participants with falls was 44% in the placebo group (11/25), 58% (15/26) in the 200 IU group, 60% (15/25) in the 400 IU group, 60% (15/25) in the 600 IU group, and 20% (5/23) in the 800 IU group. Participants in the 800 IU group had a 72% lower adjusted‐incidence rate ratio of falls than those taking placebo over the 5 months (rate ratio=0.28; 95% confidence interval=0.11–0.75). No significant differences were observed for the adjusted fall rates compared to placebo in any of the other supplement groups.CONCLUSION: Nursing home residents in the highest vitamin D group (800 IU) had a lower number of fallers and a lower incidence rate of falls over 5 months than those taking lower doses. Adequate vitamin D supplementation in elderly nursing home residents could reduce the number of falls experienced by this high falls risk group.