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Biomedical subjects

S Henderson

Publications and source records attributed to S Henderson.

At least 91 records · Page 5Linked to original sources
PubMed1996

Effects of theophylline and ipratropium on cognition in elderly patients with chronic obstructive pulmonary disease.

OBJECTIVES: To determine whether chronic therapy with theophylline or ipratropium has an adverse effect on cognition and psychomotor skills in geriatric patients with chronic obstructive pulmonary disease. DESIGN: The study design was a randomized, repeated measures, double-blind, double-dummy, placebo-controlled comparison of theophylline and ipratropium treatments. SETTING: Ambulatory patients were tested at the Clinical Trials Center of the University of California, San Diego, Medical Center. PATIENTS: Ambulatory patients with chronic obstructive pulmonary disease aged 65 years or more with FEV1 less than 60% predicted, FEV1/FVC less than 70%, and post bronchodilator FEV1 less than 70%. INTERVENTIONS: Patients received either theophylline or ipratropium for 2 weeks, followed by a 1-week placebo control period, then a 2-week treatment period of the alternative drug therapy. A standard therapy of albuterol MDI, 2 puffs (180 microg) qid was given throughout the study. MEASUREMENTS: The main response level was an 11-part battery of psychometric tests. Tests were administered at the end of each treatment period and at the end of the washout period. Covariates were sequence of treatment, pulmonary function tests, age, and baseline psychometric test scores. RESULTS: There was no difference in performance scores on the cognitive tests among the three treatment periods. CONCLUSIONS: We were unable to detect a harmful effect of treatment with either theophylline or ipratropium on the performance of elderly patients with chronic obstructive pulmonary disease on a battery of psychometric tests, suggesting that significant cognitive impairment in the elderly is not commonly associated with treatment with either theophylline or ipratropium.

Aged↗
PubMed1996

Evaluation of the corpus callosum in clumsy children born prematurely: a functional and morphological study.

The aim of this study was to evaluate the incidence of functional and neuroradiological abnormalities of the corpus callosum in a group of 21 prematurely born children (GA < 34 weeks) who were found to be "clumsy" on the Movement Assessment Battery for Children at 6 years of age. All children underwent functional and morphological assessment of the corpus callosum. The functional assessment included tests of somesthesis, diadochokinesis and repetitive finger tapping. The morphology of the corpus callosum was evaluated on midsagittal MRI. Thirteen of the 21 clumsy children showed morphological abnormalities which were significantly associated with functional abnormalities. Morphological changes of the corpus callosum were also significantly associated with lesions on both neonatal ultrasound and late MRI. Our results support the view that morphological abnormalities of the corpus callosum are frequent in children born prematurely. The association between these abnormalities and lesions on US or MRI suggests that they are likely to be secondary to pre- or perinatal lesions.

Agenesis of Corpus Callosum↗
PubMed1996

Inner dynein arms but not outer dynein arms require the activity of kinesin homologue protein KHP1(FLA10) to reach the distal part of flagella in Chlamydomonas.

Inner dynein arms, but not outer dynein arms, require the activity of KHP1(FLA10) to reach the distal part of axonemes before binding to outer doublet microtubules. We have analyzed the rescue of inner or outer dynein arms in quadriflagellate dikaryons by immunofluorescence microscopy of p28(IDA4), an inner dynein arm light chain, or IC69(ODA6), an outer dynein arm intermediate chain. In dikaryons two strains with different genetic backgrounds share the cytoplasm. As a consequence, wild-type axonemal precursors are transported to and assembled in mutant axonemes to complement the defects. The rescue of inner dynein arms containing p28 in ida4-wild-type dikaryons progressively occurred from the distal part of the axonemes and with time was extended towards the proximal part. In contrast, the rescue of outer dynein arms in oda2-wild-type dikaryons progressively occurred along the entire length of the axoneme. Rescue of inner dynein arms containing p28 in ida4fla10-fla10 dikaryons was similar to the rescue observed in ida4-wild-type dikaryons at 21 degrees C, whereas it was inhibited at 32 degrees C, a nonpermissive temperature for KHP1(FLA10). In contrast, rescue of outer dynein arms in oda2fla10-fla10 dikaryons was similar to the rescue observed in oda2-wild-type dikaryons at both 21 degrees and 32 degrees C and was not inhibited at 32 degrees C. Positioning of substructures in the internal part of the axonemal shaft requires the activity of kinesin homologue protein 1.

Algal Proteins↗
PubMed1996

In situ analysis of changes in telomere size during replicative aging and cell transformation.

Telomeres have been shown to gradually shorten during replicative aging in human somatic cells by Southern analysis. This study examines telomere shortening at the single cell level by fluorescence in situ hybridization (FISH). FISH and confocal microscopy of interphase human diploid fibroblasts (HDFs) demonstrate that telomeres are distributed throughout the nucleus with an interchromosomal heterogeneity in size. Analysis of HDFs at increasing population doubling levels shows a gradual decrease in spot size, intensity, and detectability of telomeric signal. FISH of metaphase chromosomes prepared from young and old HDFs shows a heterogeneity in detection frequency for telomeres on chromosomes 1, 9, 15, and Y. The interchromosomal distribution of detection frequencies was similar for cells at early and late passage. The telomeric detection frequency for metaphase chromosomes also decreased with age. These observations suggest that telomeres shorten at similar rates in normal human somatic cels. T-antigen transformed HDFs near crisis contained telomere signals that were low compared to nontransformed HDFs. A large intracellular heterogeneity in telomere lengths was detected in two telomerase-negative cell lines compared to normal somatic cells and the telomerase-positive 293 cell line. Many telomerase-negative immortal cells had telomeric signals stronger than those in young HDFs, suggesting a different mechanism for telomere length regulation in telomerase-negative immortal cells. These studies provide an in situ demonstration of interchromosomal heterogeneity in telomere lengths. Furthermore, FISH is a reliable and sensitive method for detecting changes in telomere size at the single cell level.

Cell Division↗
PubMed1996

Effect of cerebral lesions on continuous performance test responses of school age children born prematurely.

Examined attention skills, as measured by the Continuous Performance Test (CPT), in a group of 64 children born premature and 40 full-term children, ages 6 to 8 years. Premature children were classified by neonatal cerebral lesions into no lesion, mild lesion, and severe lesion groups. It was predicted that severity of lesion would be associated with CPT performance. While mean differences among the groups of prematures did not reach significance, children with severe lesions made significantly more errors of omission and commission than the full-term comparison group. Children with mild lesions were poorer than full terms in errors of commission. Children with no lesions also made more errors of omission and commission than full terms, suggesting attention deficits secondary to prematurity even in the absence of identified brain lesion. With increasing severity of lesion, increasing percentages of each group were found to perform more than 2 SD below the mean in errors of commission. Results suggest that premature children, with and without identified lesions, are at risk for attention deficits.

Attention↗
PubMed1996

Mental health and adequacy of social support: a four-wave panel study.

LISREL analyses with manifest variables were used to examine the causal relationship between mental health and adequacy of social integration and of attachment, measured at four consecutive waves each four months apart, in a representative sample of 225 adult residents in Canberra. Mental health was assessed with the 30-item General Health Questionnaire. The analyses suggest that while there is no temporal relationship between adequacy of attachment and mental health, adequacy of social integration is influenced by earlier mental health. The temporal relationship between adequacy of attachment and adequacy of social integration appears to be reciprocal.

Adult↗
PubMed1995

Insomnia in the elderly: its prevalence and correlates in the general population.

OBJECTIVE: To estimate the prevalence of persistent insomnia and its correlates in samples of people living in the community and in institutional settings. METHODS: Respondents were interviewed in their place of residence by trained interviewers using the Canberra Interview for the Elderly, a structured psychiatric examination. RESULTS: Information about sleeping habits was obtained from 874 community and 59 institutional residents. Insomnia was persistent in 16% of the community-dwelling population and 12% of the institutional residents, with 15% and 40%, respectively, regularly taking a hypnotic. Of those without insomnia, 10% in the community but over a third in institutions were using a hypnotic. Insomnia was associated with depression, pain and poor physical health. CONCLUSIONS: Persistent insomnia in the elderly, as in other age groups, is strongly associated with depressed mood, as well as with physical disease. Because of this, insomnia should not be dismissed as a normal part of ageing, and therefore ignored as a significant symptom. Continued surveillance is needed in general practice, geriatric services and nursing homes of the routine use of hypnotics by the elderly.

Activities of Daily Living↗
PubMed1995

Marrow development and its relationship to bone formation in vivo: a histological study using an implantable titanium device in rabbits.

During embryogenesis, the creation of marrow sinusoids is intimately related to the coupled processes of osteogenesis and osteoclastic resorption. We set out to further define the relationship between bone formation and marrow development by implanting an intraosseous titanium device into the tibiae of rabbits which permits the examination of bone formation under standardized and reproducible conditions as well as allowing repeated sampling of new bone. A hollow channel is incorporated into the device into which tissue can grow. The device was left in place for 6 weeks to allow osseous integration to occur, after which the initial rod of new tissue growth was removed and subsequent histological and immunohistological sequence of events observed over the next 7 weeks. Interpretation of its morphological changes was further aided by concurrent histomorphometric studies. Because the channel was in direct continuity with the marrow cavity and isolated from the endosteum, immediate marrow regeneration was expected, following dissolution of the blood clot. Instead, our studies indicated that hemopoietic marrow cells, including the erythroid and myeloid series as well as megakaryocytes, did not appear until 3 weeks after implantation of the chamber when the newly formed bone had been remodeled to form an expanded marrow cavity. This intraosseous device is a useful in vivo model for studying the development of bone marrow hemopoietic and nonhemopoietic stromal cells and our results confirm the previous observation that influx of marrow cellular elements follow the formation of bone during endochondral as well as intramembranous ossification.

Animals↗
PubMed1995

Minor neurological and perceptuo-motor deficits in children with congenital muscular dystrophy: correlation with brain MRI changes.

Diffuse white matter changes on magnetic resonance imaging (MRI) have been a consistent feature in some children with the "pure" form of congenital muscular dystrophy (CMD) in which there are no structural changes in the brain or severe mental retardation. The aim of this study was to assess fine motor and perceptuo-motor abilities in children with CMD with and without MRI changes. Twenty-two children with "pure" CMD were investigated with a standard neurological examination and a battery of tests (Manual dexterity from the Movement ABC, test of visual-motor integration, Zurich Neuromotor test) which have already been used to detect minor neurological signs related to white matter changes. The cohort was then divided in two groups for analysis depending on the presence or the absence of diffuse white matter changes. A significant difference was found for all the tests between the group of the CMD children with normal MRI and the group with diffuse white matter changes. The manual dexterity and the Zurich Neuromotor tests showed a greater sensitivity than the test of visual-motor integration, which had some false negatives. It is of interest that in the group with diffuse white matter changes the presence of contractures or weakness did not seem to affect the quality of the performance; all these children scored abnormally on the test, irrespective of the severity or the extent of contractures and weakness. In contrast, in children with normal MRI severe contractures and weakness did affect the performances. Our results demonstrate that perceptuo-motor difficulties and minor neurological soft signs are a consistent feature in CMD children with diffuse MRI changes but not with normal MRI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Speaking of difficult choices: the creation of a drama and dialogue group on end-of-life choices.

The purpose of this project is to relieve the emotional isolation of elders concerned about the manner in which they will die, particularly fears about loss of control. A counselor engaged elders in dialogue exploring nonthreatening ways this could be done. Drama that includes dialogue with the audience was chosen, developed, and performed at their retirement facility and in the wider community. Elders who attend these performances express gratitude and relief at learning they are not alone in their concerns, and for the information about current laws and resources for support.

Aged↗
PubMed1995

Spinal meningiomas in women in Los Angeles County: investigation of an etiological hypothesis.

A series of 3 studies explored the hypothesis that the preponderance of spinal meningiomas among postmenopausal women relates to their higher prevalence of spinal osteoporosis: (a) medical records showed that meningiomas in women, unlike other spinal tumors, usually arise in the mid thoracic spine where osteoporotic vertebral fractures predominate; (b) radiographic evidence of osteoporosis was seen commonly with meningiomas but not with other spinal tumors; and (c) age-adjusted multivariate analysis of data from an interview study of 81 women with spinal meningioma and 155 random digit dial controls showed 6 factors related to risk. Four factors were protective: (a) current use (at diagnosis) of estrogen replacement therapy [odds ratio (OR) = 0.2; 95% confidence interval (CI) = 0.1-0.6]; (b) past use of oral contraceptives (P trend < 0.01); (c) past participation in sports (OR = 0.5; CI = 0.2-0.9); and (d) premenopausal status (OR = 0.2; CI = 0.1-0.7). Risk increased among women who had ever smoked cigarettes (OR = 1.7; CI = 0.9-3.1) or had a history of high dose radiography (> 500 mrad exposure to active marrow/examination; includes upper or lower gastrointestinal series and/or cardiac angiography; OR = 2.9, and CI = 1.6-5.3), although no association was seen with prior radiotherapy. Other results that did not support the hypothesis include findings that cases and controls were similar in mean body weight and in the proportion who had postmenopausal fractures or height loss. In conclusion, these studies lend some support to our hypothesis, but other known meningioma risk factors such as ionizing radiation also appear important.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗