Dilemmas in geriatrics: scenario 3 results.
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Accidental Falls↗
Biomedical subjects
F Anderson
Publications and source records attributed to F Anderson.
Current management of ALS: comparison of the ALS CARE Database and the AAN Practice Parameter. The American Academy of Neurology.
BACKGROUND: The American Academy of Neurology (AAN) ALS Practice Parameter was published in April 1999. The ALS CARE Database has been collecting data on the management of patients with ALS in North America since 1996. OBJECTIVE: To compare the management of patients with ALS in North America as recorded in the ALS CARE Database with the recommendations of the AAN ALS Practice Parameter. METHODS: Data were analyzed from 2018 patients at enrollment and from 373 of these patients who died between enrollment and May 1999. RESULTS: Eighty-two percent of the enrolled patients reported that they had been given enough information about ALS. Only 54% of patients with drooling were receiving medication for this problem. Only 41% of those who reported being depressed most of the time were receiving antidepressant medications. Only 28% of those with dyspnea and only 9.2% of those with a forced vital capacity <40% predicted were receiving noninvasive positive pressure ventilator support. Only 30% of those with moderate to severe dysphagia had a gastrostomy tube. Half of the patients who died did so at home, but only 47% of them received residential hospice services. Although 89% of patients who died were recorded as having done so peacefully, 17% were reported to have had breathing difficulties (i.e., respiratory distress), 8% anxiety, 3.3% pain, and 2.5% choking. Advance directives were in place for 90% of the patients who died, and in 97% of cases these directives were followed. CONCLUSIONS: These findings indicate that in the 3-year period prior to the publication of the AAN Practice Parameter, many but not all patients received the care that is recommended in that parameter; there were deficiencies, particularly in the key areas of gastrostomy and noninvasive positive pressure ventilation.
Amyotrophic Lateral Sclerosis↗
Receptor activator of NF-kappa B and osteoprotegerin expression by human microvascular endothelial cells, regulation by inflammatory cytokines, and role in human osteoclastogenesis.
The receptor activator of NF-kappaB (RANKL) is the essential signal required for full osteoclast (OC) development, activation, and survival. RANKL is highly expressed in areas of trabecular bone remodeling and inflammatory bone loss, is increased on marrow stromal cells or osteoblasts by osteotropic hormones or cytokines, and is neutralized by osteoprotegerin (OPG), a soluble decoy receptor also crucial for preventing arterial calcification. Vascular endothelial cells (VEC) are critically involved in bone development and remodeling and influence OC recruitment, formation, and activity. Although OCs develop and function in close association with bone VEC and sinusoids, signals mediating their interactions are not well known. Here, we show for the first time that human microvascular endothelial cells (HMVEC) express transcripts for both RANKL and OPG; inflammatory cytokines tumor necrosis factor-alpha and interleukin-1alpha elevate RANKL and OPG expression 5-40-fold in HMVEC (with an early OPG peak that declines as RANKL rises), and RANKL protein increases on the surface of tumor necrosis factor-alpha-activated HMVEC. Cytokine-activated HMVEC promoted the formation, fusion, and bone resorption of OCs formed in co-cultures with circulating human monocytic precursors via a RANKL-mediated mechanism fully antagonized by exogenous OPG. Furthermore, paraffin sections of human osteoporotic fractured bone exhibited increased RANKL immunostaining in vivo on VEC located near resorbing OCs in regions undergoing active bone turnover. Therefore, cytokine-activated VEC may contribute to inflammatory-mediated bone loss via regulated production of RANKL and OPG. VEC-derived OPG may also serve as an autocrine signal to inhibit blood vessel calcification.
Base Sequence↗
Assessing health status quality of life in ALS: comparison of the SIP/ALS-19 with the ALS Functional Rating Scale and the Short Form-12 Health Survey. ALS C.A.R.E. Study Group. Clinical Assessement, Research, and Education.
BACKGROUND: The progressive loss of function affects the quality of life of the ALS patient. Quality of life depends on a spectrum of factors. Available instruments for assessment include questionnaires developed for generic illness-related disabilities and ALS-specific questionnaires that focus on function. METHODS: Comparisons were made between two ALS-specific questionnaires (ALS Functional Rating Scale and SIP/ALS-19) and a generic instrument (Short Form-12) given to 1,513 patients from the (North American) ALS Patient Care Database. RESULTS: The SIP/ALS-19 correlates well with the ALS Functional Rating Scale and less well with the Short Form-12. CONCLUSIONS: The SIP/ALS-19 can be used as an effective surrogate for the ALS Functional Rating Scale, with the advantage that the SIP/ALS-19 also includes questions that encompass the psychological and social domains of quality of life.
Activities of Daily Living↗
Transcription-mediated amplification is more sensitive than conventional PCR-based assays for detecting residual serum HCV RNA at end of treatment.
OBJECTIVE: In patients chronically infected with hepatitis C virus (HCV) undergoing antiviral therapy, sustained virologic response is suggested by viral clearance by end of treatment (EOT). Viral clearance is defined by nondetection of serum HCV RNA, usually by qualitative PCR-based assays with limits of detection ranging from 100 to 1000 copies/ml. However, some individuals relapse after achieving apparent viral clearance by EOT. These individuals may have low levels of viremia not detected by current PCR methods. The aim of this retrospective study was to determine whether the Bayer HCV RNA Qualitative Assay, which employs Transcription Mediated Amplification (TMA) and detects 50 HCV RNA copies/ml, could detect residual serum HCV RNA in patients who achieved apparent viral clearance by EOT and subsequently relapsed. METHODS: Samples were obtained at EOT (wk 24 or 48) and follow-up (wk 24-26 posttreatment) from 97 patients treated for HCV (78 relapsing patients, 19 sustained responders). All samples in which HCV RNA was not detected by PCR were tested in a blinded manner for HCV RNA by the TMA-based assay. RESULTS: HCV RNA was detected by the TMA-based assay in 27 (34.6%) EOT and 76 (97.4%) follow-up samples from relapsing patients, but not in any of the EOT or follow-up samples from sustained responders. CONCLUSION: Residual serum HCV RNA was detected by the TMA-based assay in EOT samples from 34.6% of patients that had achieved apparent viral clearance by PCR. The detection of HCV RNA by the TMA-based assay could help redefine EOT response and assist in the antiviral management of HCV infection.
Antiviral Agents↗
[Is the era of general practice over?].
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Family Practice↗
Decreased nitric oxide levels stimulate osteoclastogenesis and bone resorption both in vitro and in vivo on the chick chorioallantoic membrane in association with neoangiogenesis.
High nitric oxide (NO) levels inhibit osteoclast (OC)-mediated bone resorption in vivo and in vitro, and nitrate donors protect against estrogen-deficient bone loss in postmenopausal women. Conversely, decreased NO production potentiates OC bone resorption in vitro and is associated with in vivo bone loss in rats and humans. Previously, we reported that bone sections from rats administered aminoguanidine (AG), a selective inhibitor of NO production via inducible NO synthase, exhibited both increased OC resorptive activity as well as greater numbers of OC. Here, we investigated further whether AG promoted osteoclastogenesis, in addition to stimulating mature OC function, using a modified in vivo chick chorioallantoic membrane (CAM) system and an in vitro chick bone marrow OC-like cell developmental model. AG, focally administered in small agarose plugs placed directly adjacent to a bone chip implanted on the CAM, dose-dependently elicited neoangiogenesis while stimulating the number, size, and bone pit resorptive activity of individual OC ectopically formed in vivo. In addition to enhancing OC precursor recruitment via neoangiogenesis, AG also exerted other vascular-independent effects on osteoclastogenesis. Thus, AG promoted the in vitro fusion and formation from bone marrow precursor cells of larger OC-like cells that contained more nuclei per cell and exhibited multiple OC differentiation markers. AG stimulated development was inversely correlated with declining medium nitrite levels. In contrast, three different NO donors each dose-dependently inhibited in vitro OC-like cell development while raising medium nitrite levels. Therefore, NO sensitively regulates OC-mediated bone resorption through affecting OC recruitment (angiogenesis), formation (fusion and differentiation), and bone resorptive activity in vitro and in vivo. Possibly, the stimulation of neoangiogenesis and OC-mediated bone remodeling via AG or other pro-angiogenic agents may find clinical applications in reconstructive surgery, fracture repair, or the treatment of avascular necrosis.
Acid Phosphatase↗
Inhibition of avian osteoclast bone resorption by monoclonal antibody 121F: a mechanism involving the osteoclast free radical system.
Osteoclasts generate high levels of superoxide anions during bone resorption that contribute to the degradative process, although excessive levels of this free radical may be damaging. One mechanism for their removal is via superoxide dismutase (SOD), a protective superoxide scavenging enzyme. We have previously described a novel developmentally regulated 150 kDa plasma membrane glycoprotein of avian osteoclasts which is reactive with the osteoclast-specific monoclonal antibody (Mab) 121F and is related immunologically, biochemically, and in protein sequence to mitochondrial Mn2+/Fe2+ SOD. We hypothesized that this unusual osteoclast surface component may be involved in protection against superoxides generated during active bone resorption. Increasing concentrations of monovalent Fab fragments prepared from Mab 121F, but not those from another antiosteoclast Mab designated 29C, markedly inhibited both bone particle and bone pit resorption by avian osteoclasts, while reducing tartrate-resistant acid phosphatase activity and causing the morphological contraction of osteoclasts on bone. Thus, the SOD-related membrane antigen may be essential for osteoclast bone resorption. Osteoclast superoxide production, monitored kinetically by cytochrome c reduction and histochemically by nitroblue tetrazolium reduction staining, was significantly greater in the presence of 121F, but not 29C, Fab treatment. Furthermore, the release of another free radical known as nitric oxide, which is produced by osteoclasts, can scavenge superoxides, and acts to potently inhibit osteoclast bone resorption, was dose-dependently increased by 121F Fab in resorbing osteoclast cultures. Therefore, Mab 121F binding may block the potential protective function of the osteoclast plasma membrane SOD-related glycoprotein, leading to a rapid elevation of superoxide levels and a subsequent rise in osteoclast nitric oxide release, feedback messages which may be sensed by the osteoclast as signals to cease active bone resorption.
Acid Phosphatase↗
Illicit use of clonidine in opiate-abusing pregnant women.
OBJECTIVE: To examine prevalence rates and psychosocial correlates of clonidine use in a sample of opiate-dependent pregnant women. METHODS: Clonidine use was assessed in 90 treatment-seeking, pregnant, opiate-abusing women using both self-report and urinalysis toxicology. Clonidine-positive and -negative subjects were compared for selected demographic, substance use, and psychosocial measures. RESULTS: One-third of the sample was clonidine-positive. Urinalysis identified 26 clonidine-positive subjects, whereas self-report detected only six cases. Logistic regression identified four predictors of clonidine use at treatment admission: recent clinical anxiety, greater severity of family or social problems, recent cocaine use, and recent drug treatment. CONCLUSION: Clonidine use is prevalent in treatment-seeking opiate abusers, particularly those with concurrent cocaine use. The abuse potential of the drug warrants further study in this high-risk population.
Adult↗
Ca2+ or phorbol ester but not inflammatory stimuli elevate inducible nitric oxide synthase messenger ribonucleic acid and nitric oxide (NO) release in avian osteoclasts: autocrine NO mediates Ca2+-inhibited bone resorption.
Osteoclast bone resorption is essential for normal calcium homeostasis and is therefore tightly controlled by calciotropic hormones and local modulatory cytokines and factors. Among these is nitric oxide (NO), a multifunctional free radical that potently inhibits osteoclast bone resorption in vitro and in vivo. Previous findings led us to propose that NO might serve as an autocrine, as well as paracrine, regulator of osteoclast function. This premise was investigated using isolated bone-resorptive avian osteoclasts and focusing on the inducible isoform of NO synthase (iNOS) responsible for inflammatory stimulated high-level NO synthesis in other cells. Avian osteoclasts expressed both iNOS messenger RNA (mRNA) and protein. However, inflammatory cytokines that induce iNOS mRNA, protein, and NO in other cells did not do so in avian osteoclasts, consistent with the known role of inflammatory stimuli in promoting osteoclast resorption and localized bone loss. In searching for potential modulators of osteoclast iNOS, protein kinase C activation [by phorbol 12-myristate 13-acetate (PMA)] and intracellular Ca2+ rises (A23187) were each found to elevate osteoclast iNOS mRNA and protein levels, while increasing NO release and reducing osteoclast bone resorption. The iNOS selective inhibitor aminoguanidine suppressed stimulated osteoclast NO production elicited by either signal, but reversed only the resorption inhibition due to raised Ca2+. Thus, whereas additional inhibitory signals are presumably coproduced in osteoclasts treated with PMA, osteoclast iNOS-derived NO may act as an autocrine signal to mediate Ca2+-inhibited bone resorption. These findings document for the first time an iNOS whose mRNA levels are regulated by Ca2+ or PMA, but not inflammatory stimuli, and the autocrine production of NO as a Ca2+ sensing signal to suppress osteoclast bone resorption. The unusual regulation of osteoclast iNOS makes it a potentially attractive target for designing novel therapeutic agents to alleviate excessive bone loss.
Animals↗
Palliative performance scale (PPS): a new tool.
The Palliative Performance Scale (PPS), a modification of the Karnofsky Performance Scale, is presented as a new tool for measurement of physical status in palliative care. Its initial uses in Victoria include communication, analysis of home nursing care workload, profiling admissions and discharges to the hospice unit, and, possibly, prognostication. We assessed 119 patients at home, of whom 87 (73%) had a PPS rating between 40% and 70%. Of 213 patients admitted to the hospice unit, 175 (83%) were PPS 20%-50% on admission. The average period until death for 129 patients who died on the unit was 1.88 days at 10% PPS upon admission, 2.62 days at 20%, 6.70 days at 30%, 10.30 days at 40%, 13.87 days at 50%. Only two patients at 60% or higher died in the unit. The PPS may become a basis for comparing drug costs at home and for studying the effects of treatments (e.g. hypodermoclysis) at various levels of physical performance. Validity and reliability testing are currently being undertaken.
British Columbia↗
Osteoclast 121F antigen expression during osteoblast conditioned medium induction of osteoclast-like cells in vitro: relationship to calcitonin responsiveness, tartrate resistant acid phosphatase levels, and bone resorptive activity.
Osteoclast differentiation from hematopoietic precursors into multinucleated cells uniquely capable of removing the organic and inorganic components of bone matrix occurs in multistep process, during which osteoclasts acquire the specialized characteristics necessary for bone resorptive activity and physiological regulation. Among those traits is a novel plasma membrane glycoprotein, reactive with the anti-osteoclast monoclonal antibody 121F, which is expressed during the course of osteoclast differentiation, shares structural and functional homologies with Mn2+/Fe2+ superoxide dismutase, and has been hypothesized to protect the osteoclast from the damaging effects of superoxide radicals generated during active bone resorption. We have reported previously that the expression of this membrane antigen is induced on multinucleated giant cells when the prefusion marrow mononuclear cells are cultured in conditioned medium from avian calvaria. The studies reported here were designed to investigate the relationship between expression of the 121F antibody-reactive osteoclast membrane antigen and tartrate resistant acid phosphatase levels, bone resorptive activity, calcitonin responsiveness, and ultrastructural features of avian bone marrow-derived multinucleated giant cells formed either in the presence or absence of diffusible osteoblast secreted factors. Parallel analyses of in vivo formed osteoclasts isolated from the same animals were performed for direct comparisons. In this report we demonstrate: (1) that the 121F monoclonal antibody-reactive osteoclast membrane antigen is stably induced in giant cells by soluble osteoblast-derived factors in a species nonrestricted but concentration- and temporal-dependent manner; (2) that osteoblast-mediated antigen induction is reflected in both increased numbers of cells and elevated expression of individual cells that are reactive with the 121F antibody, as determined by ELISA and histomorphometry; (3) that osteoblast conditioned medium, in addition to inducing this antigen in bone marrow cells, also elevates other defining osteoclast characteristics in these avian giant cells including their TRAP activity, cell retraction from the bone surface in response to calcitonin, bone resorptive function, and expression of a series of additional osteoclast antigenic markers; and (4) that secreted osteoblast products alone do not raise the levels of these traits for in vitro formed marrow giant cells to the extent associated with in vivo formed osteoclasts. Therefore, osteoblast soluble factors alone appear unable to promote the full differentiation of bone marrow cells in vitro into mature bone-resorbing osteoclasts.(ABSTRACT TRUNCATED AT 400 WORDS)
Acid Phosphatase↗
Pharmacokinetics of a single dose of buccal testosterone.
The bioavailability, pharmacokinetics, and metabolism of a novel transbuccal delivery system of testosterone was investigated in five healthy eugonadal men. Total serum testosterone (T), dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) concentrations were determined from blood samples obtained at 8:00 a.m. (zero hour), and 30 min and 1, 2, 3, 4, 6, 12 and 24 hours later on day 1, and again on day 2, after dosing. This single transbuccal administration of Buccal T induced a prompt rise in serum T and DHT concentrations. The maximal concentration (Cmax) of T was 19.56 7.64 ng/mL (mean +/- SD; 5.3-fold increase from the baseline) at< 30 min (Tmax) after administration. The elimination half-life of Buccal T was about 1.75 h. Serum DHT peaked at 1 h at a concentration of 1.46 +/- 0.46 ng/mL (2.3-fold increase from the baseline). The drug was well tolerated. This study suggests that the Buccal T is a promising delivery system for natural T.
Administration, Buccal↗
The evolution of sugar isomerases.
L-Arabinose isomerase (EC 5.3.1.4) catalyzes the isomerization of L-arabinose to L-ribulose. Here we report on the purification, kinetic mechanism and chemical mechanism of L-arabinose isomerase from Escherichia coli. The enzyme catalyzes the isomerization of L-arabinose to L-ribulose by a proton transfer mechanism, in contrast to xylose isomerase which uses a hydride transfer mechanism to perform a similar isomerization. Arabinose isomerase activity is metal dependent, although the enzyme can catalyze the exchange of the proton attached to carbon 2 of arabinose with the solvent in the absence of metal ion. Manganese(II) is the only metal ion which renders the enzyme active for the isomerization reaction. Arabinose isomerase has high substrate specificity for L-arabinose. The difference in chemical mechanism between xylose isomerase and arabinose isomerase suggests that these enzymes are not related by convergent evolution. This work also suggests that unless convergent evolution has been demonstrated, the mechanism of one enzyme may not give any insight into the mechanism of a second enzyme catalyzing the same reaction.
Aldose-Ketose Isomerases↗
Developing a hospital ethics committee.
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Ethics Committees↗
Attitudes of women to fetal tissue research.
The use of human fetal tissue for scientific research has enormous potential but is subject to government legislation. In the United Kingdom the Polkinghorne Committee's guidelines were accepted by the Department of Health in 1990. These guidelines set out to protect women undergoing termination of pregnancy from exploitation but in so doing may significantly restrict potential research. Although the committee took evidence from a wide variety of experts they did not seek the views of the general public. We asked 108 women about to have a therapeutic abortion; 167 women who had had a pregnancy terminated in the past, and 419 women who had never had an abortion, their views on research using human fetal tissue. Regardless of their past experiences the women were overwhelmingly in favour of research using fetal tissue (94 per cent). They made little distinction between basic research and research with obvious clinical relevance and supported the concept of using transplanted fetal tissue for the treatment of adult disease such as Parkinsonism. Women about to undergo an abortion were significantly more likely (p < 0.001) to approve of all types of research including that aimed at improving methods of abortion and research using live fetuses in utero.
Aborted Fetus↗
Age-related changes in beta-adrenergic neuroeffector systems in the human heart.
BACKGROUND: Aging decreases cardiac beta-adrenergic responsiveness in model systems and in humans in vivo. The purpose of this study was to comprehensively evaluate the age-related changes in the beta-receptor-G protein-adenylyl cyclase complex in nonfailing human hearts. METHODS AND RESULTS: Twenty-six nonfailing explanted human hearts aged 1 to 71 years were obtained from organ donors and subjected to pharmacological investigation of beta-adrenergic neuroeffector systems. When the population was subdivided into the 13 youngest and 13 oldest subjects, total beta-receptor density assessed by maximum [125I]ICYP binding (beta max) was reduced in older hearts by 37% in left ventricles and 31% in right ventricles (both P < .05), and the downregulation was confined to the beta 1 subtype (r = .78 left ventricle beta 1 density versus donor age). Older donor hearts exhibited a 3- to 4-fold rightward shift of ICYP-isoproterenol (ISO) competition curves and demonstrated 43% fewer receptors in a high-affinity agonist binding state (P < .05). Older hearts exhibited decreased adenylyl cyclase stimulation by ISO, by zinterol (beta 2-agonist), and by the G protein-sensitive probes forskolin, Gpp(NH)p, and NaF. In contrast, there was no change in response to manganese, a specific activator of the adenylyl cyclase catalytic subunit. Toxin-catalyzed ADP ribosylation in membranes prepared from older versus younger hearts revealed a 29% to 30% reduction (P < .05) with cholera toxin (Gs) but no difference with pertussis toxin (Gi). The systolic contractile response of isolated right ventricular trabeculae to ISO was decreased by 46%, with a 10-fold increase in ISO EC50 in older relative to younger donor hearts. CONCLUSIONS: There is a profound decrease in cardiac beta-adrenergic responsiveness with aging. This occurs by multiple mechanisms including downregulation and decreased agonist binding of beta 1-receptors, uncoupling of beta 2-receptors, and abnormal G protein-mediated signal transduction.
Adenylyl Cyclases↗
Kinetics and pharmacology of estrogens in pre- and postmenopausal women.
With the approach of the menopause and the cessation of ovarian estrogen production, a number of uncomfortable and/or dangerous conditions may be manifested, and are all indications for estrogen replacement therapy. Various routes of estrogen administration are available--oral, subcutaneous implant, intravaginal, and transdermal--each having advantages and disadvantages. There is also a choice possible among replacement hormones, which include the natural estrogens, such as estradiol and estropipate; synthetic estrogens, for example, ethinyl estradiol and diethylstilbestrol; and conjugated equine estrogens. Depending on both route of administration and choice of hormone, there are great differences demonstrable in kinetics and pharmacologic characteristics, which have not been reflected, however, by highly significant differences in clinical outcome so far.
Adult↗