Elderly people's technique in using dry powder inhalers. New inhaler devices are rarely used by older people in the community.
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Biomedical subjects
Publications and source records attributed to L Fowler.
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Previous work has shown that N-methyl-D-aspartate (NMDA) receptor activation decreases 5-hydroxytryptamine (5-HT) release in the hippocampus of freely moving rats. Given the association between NMDA receptor function and nitric oxide (NO) production with the regulation of 5-HT release in other brain regions, we have studied this in rat hippocampus. NMDA (100 microM) decreased hippocampal 5-HT release by approximately 70% and this was reversed by the NMDA receptor antagonist 2-amino-5-phosphonopentanoic acid (AP5; 10 microM). The NO donor S-nitroso-N-acetylpenicillamine (SNAP) had an inverse concentration-dependent effect on 5-HT release. At 500 microM, SNAP elevated dialysate 5-HT by 55% over basal, while at 5 mM a 70% decrease was seen. The non-selective nitric oxide synthase (NOS) inhibitor N-nitro-L-arginine methyl ester (L-NAME) at 1 mM increased extracellular 5-HT, although a return to basal levels occurred despite the continued presence of the drug. At 1 mM L-NAME prevented the decrease in 5-HT elicited by NMDA (100 microM) infusion. 7-Nitroindazole (7-NI), a relatively selective neuronal NOS (nNOS) inhibitor, decreased extracellular 5-HT at 100 microM and 1 mM. When 100 microM 7-NI was infused for 60 min prior to NMDA, 5-HT levels were transiently increased above basal before returning to control levels. Following combined application of the two drugs, no decrease in dialysate 5-HT was seen. Our data support a role for NO in modulating both basal and NMDA-evoked changes in 5-HT release in the hippocampus, however, the association appears to be complex. It may be that the recorded changes in 5-HT release are secondary to changes in the release of amino acid transmitters which we have previously found to be dependent on the prevailing extracellular NO concentration.
BACKGROUND: A study was undertaken to estimate the prevalence of untreated asthma in older adults. METHODS: A cross sectional population based survey of 6000 men and women aged 65 years and over was performed in 21 general practices in north Bristol, south west England. The main outcome measure was untreated asthma as defined by a two stage process comprising a respiratory questionnaire (symptoms suggestive of asthma or doctor diagnosed asthma not receiving respiratory treatment) followed by lung function tests (significant reversibility following bronchodilators or corticosteroids and/or significant within day variability in peak expiratory flow). RESULTS: 4792 of the 6000 participants (80%) completed the respiratory questionnaire and, of those not receiving respiratory treatment, 55 reported a previous doctor diagnosis of asthma and a further 696 had symptoms suggestive of asthma. Lung function testing in 280 of 501 randomly selected individuals from these groups resulted in 38 being defined as having asthma and an estimated population prevalence for untreated asthma of 2.4% (95% CI 1.6% to 3.6%) in men and 1.2% (95% CI 0.7% to 2.1%) in women. Most subjects (84%) with untreated asthma had moderate or severe disease. Untreated asthma was most common in individuals with doctor diagnosed asthma (21%) and those with breathlessness or wheeze (13-20%). CONCLUSION: Untreated asthma in the elderly is a common and important problem. Opportunistic use of appropriate lung function tests in older people with a history of doctor diagnosed asthma or wheeze or breathlessness at rest could identify untreated asthmatics who might benefit from treatment.
Infusion of N-methyl-D-aspartate (NMDA) into the hippocampus of freely moving rats produced a concentration-dependent decrease in the extracellular levels of dopamine, an effect which was reversed by D-2-amino-5-phosphonovaleric acid (D-AP5). To determine the involvement of nitric oxide (NO) in this response, two nitric oxide synthase (NOS) inhibitors, N-nitro-L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI), were examined for their ability to modify both basal and NMDA-inhibited dopamine release. When infused alone both NOS inhibitors elicited an increase in extracellular dopamine concentration, moreover, when administered prior to the application of NMDA, the agonist failed to elicit a decrease in dopamine levels. Infusion of the NO donor S-nitroso-N-acetylpenicillamine (SNAP) over a 30 min period caused either an increase or a decrease in dopamine release depending upon the concentration used. At the lower concentration (0.5 mM) SNAP promoted dopamine release whilst at the higher concentration (5 mM), the donor elicited a long lasting reduction in basal dopamine levels. The effect of the lower concentration of SNAP was reversed by the prior application of D-AP5, but that of the higher concentration was unaffected by the antagonist.
BACKGROUND: Studies in children and young women have indicated an increased risk of respiratory illness in association with the use of domestic gas appliances, possibly caused by oxides of nitrogen generated when gas is burned. It is not known whether risks are similarly increased in older subjects. METHODS: A questionnaire about respiratory symptoms in the past year and potential risk factors for respiratory disease was mailed to 6000 men and women aged 65 years and older who were selected at random from the lists of general practices in North Bristol, UK. Associations between symptoms and the use of gas appliances were examined by logistic regression with adjustment for age, sex, social class, and smoking habits. RESULTS: Questionnaires were completed by 4792 (80%) of those mailed. The most common symptoms were exercise induced breathlessness, wheeze, or chest tightness (51%); wheeze (27%); morning phlegm (20%); and daytime breathlessness at rest (19%). In an analysis that included all subjects only weak associations were found with use of gas appliances, odds ratios all being 1.2 or less. The risks associated with use of a gas hob tended to be higher in women, with odds ratios of 1.36 (95% CI 1.01 to 1.83) for wheeze and 1.33 (95% CI 0.56 to 3.17) for morning chest tightness, but were lower than had been reported previously in younger women. CONCLUSION: The absence of stronger associations cannot readily be explained by bias or confounding. Gas cookers and fires are unlikely to be an important cause of respiratory illness in the elderly. If they do cause such illness, the largest risks are likely to be in women who use gas hobs.
Adducins are cytoskeletal proteins that facilitate interactions between spectrin and actin to form the subcortical membrane skeleton. We recently determined that alpha- and gamma-adducins are among a group of PKC substrates that we have designated "STICKS" (substrates that interact with C-kinase). To study the role of adducins and their regulation by protein kinase C (PKC) in carcinogenesis, we compared the content, localization, and phosphorylation of alpha- and gamma-adducins in primary renal proximal tubule epithelial (RPTE) cells and oncogene-altered derivative lines. RPTE cells expressing adenovirus E1A are immortalized but not transformed, whereas RPTE cells expressing SV40 large T antigen are transformed. Phosphorylation of adducins was monitored with a phosphorylation state-specific antibody directed toward the PKC phosphorylation site on adducins. Basal levels of phospho-alpha-adducin were relatively low in growing and confluent primary RPTE cells; however, basal levels of phosphoadducins relative to total adducins were increased in E1A-RPTE and SV40-RPTE cells. Phorbol esters stimulated alpha-adducin phosphorylation to a greater extent in primary cells than in oncogene-altered cells, possibly because of the already high basal levels of phosphorylation in those cells. Phosphorylated adducins were preferentially recovered in the soluble fraction, indicating that PKC phosphorylation either directly or indirectly influences the subcellular location and functions of adducins in regulating membrane skeleton structure. Thus, these studies provide evidence for increased endogenous PKC activity in oncogene-altered cells and suggest that the increased activity directly influences cytoskeletal organization by phosphorylating regulatory proteins, such as the adducins.
Tumor promotion/progression is known to be due in part to increased signaling through a variety of mitogenic pathways, including protein kinase C (PKC). To determine whether increased PKC activity could play a role in promotion and progression of renal cancer, we monitored PKC activity in normal and progressively transformed renal neoplasias from Eker rats. Eker rats carry a defect in the tumor suppressor TSC2 gene that predisposes them to renal carcinoma, whereas additional factors influence tumor promotion/progression in accordance with a "two-hit" model. We used the phosphorylation of adducins at Ser-660, a known PKC phosphorylation site, as a reporter for endogenous PKC activity. In normal proximal tubules, total adducin levels (measured with a phosphorylation state-insensitive antibody) were relatively high, whereas pSer660-adducin (measured with a phosphorylation state-sensitive antibody) levels were very low. In comparison, in renal carcinomas, total adducin levels were decreased, and pSer-660-adducin levels were increased. Changes in phosphorylation correlated with changes in localization. In normal tissue, alpha- and gamma-adducin are targeted to the apical and basal membranes of proximal tubules, respectively, implying unique functions for these related proteins. In early lesions (atypical tubules), differential targeting is lost, and both alpha- and gamma-adducins localize to the basal membrane. In more advanced lesions, staining in lateral membranes at cell-cell contacts becomes apparent. Furthermore, in cells that have lost basement membrane contact, plasma membrane targeting is no longer apparent. These changes in adducin expression levels, phosphorylation state, and localization parallel the increased growth potential and dedifferentiation of the progressive tumor phenotypes. These data demonstrate the utility of phosphorylation state-selective antibodies in immunohistochemical applications as reporters of endogenous PKC activity in tissue samples. We also provide the first evidence that increased PKC activity and phosphorylation of important target proteins occurs during progressive transformation in a non-phorbol ester tumor promotion model in vivo.
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We recently cloned a partial cDNA (35H) for a protein kinase C (PKC) binding protein from a rat kidney cDNA library and demonstrated that it is a PKC substrate in vitro (Chapline, C., Ramsay, K., Klauck, T., and Jaken, S. (1993) J. Biol. Chem. 268, 6858-6861). Additional library screening and 5' rapid amplification of cDNA ends were used to obtain the complete open reading frame. Amino acid sequence analysis, DNA sequence analysis, and Northern analysis indicate that 35H is a unique cDNA related to alpha-and beta-adducins. Antisera prepared to the 35H bacterial fusion protein recognized two polypeptides of 80 and 90 kDa on immunoblots of kidney homogenates and cultured renal proximal tubule epithelial cell extracts. The 35H-related proteins were similar to alpha- and beta-adducins in that they were preferentially recovered in the Triton X-100-insoluble (cytoskeletal, CSK) fraction of cell extracts and were predominantly localized to cell borders. Phorbol esters stimulated phosphorylation of CSK 35H proteins, thus emphasizing that sequences isolated according to PKC binding activity in vitro are also PKC substrates in vivo. The phosphorylated forms of the 35H proteins were preferentially recovered in the soluble fraction, thus demonstrating that phosphorylation regulates their CSK association and, thereby, their function in regulating cytoskeletal assemblies. We have isolated another PKC binding protein partial cDNA (clone 45) from a rat fibroblast library with substantial homology to alpha-adducin. Antisera raised against this expressed sequence recognized a protein of 120 kDa, the reported size of alpha-adducin, on immunoblots of renal proximal tubule epithelial cell extracts. A 120-kDa protein that cross-reacts with the clone 45 (alpha-adducin) antisera coprecipitated with 35H immunecomplexes, indicating that alpha-adducin associates with 35H proteins in vivo. Taken together, these results indicate that 35H is a new, widely expressed form of adducin capable of forming heterodimers with alpha-adducin. We propose naming this adducin homologue gamma-adducin.
This article described a method of patient and family intervention designed for psychotic patients who are prone to relapse. Issues addressed in a monthly group meeting were designed to clarify, inform, and support families on the facts of schizophrenia and bipolar disorder. This format succeeded in improving the rate of recidivism in the population of Caribbean patients because it clarified distortions of the nature of the illnesses and made obvious that medication compliance was separate and did not intrude on the culture and belief systems. Family dynamics were not a focus in this psychoeducation program, but alliances, boundaries, and process did change over the course of the 6 months of the program. Family members were engaged relatively easily and responded when it was clear there was no intention to intrude on culture or personal beliefs. Many expressed anger and frustrations that such a program had not been offered before, especially those families whose relatives had experienced multiple readmissions. The questionnaires clearly illustrated an increase in knowledge and understanding about the illness, and this correlated with reduced recidivism. A major effort is made to maintain contact with patients and their families following discharge from the day hospital for up to 3 years to ensure their follow-through. Follow-up phone calls ensure 100% follow-up. For the past few years, we have found that ongoing contact is also useful on a reduced frequency to reinforce the concepts communicated initially.
A comprehensive review of our series of surgical perilymphatic fistula (PLF) repairs, as well as a review of published results from other otologists, suggested an unacceptably high rate of postoperative PLF recurrence. Some recurrences were related to specific events (i.e., coughing, strenuous activity, Valsalva-type maneuvers). However many cases had no apparent cause. Rather, the patients' symptoms recurred spontaneously, and at reoperation the graft was seen to have not "taken," suggesting graft failure rather than "patient failure." After a critical evaluation of current PLF surgical procedures and state-of-the-art concepts of wound healing, we developed a new surgical technique for PLF closure. Combining the use of laser graft-site preparation, an autologous fibrin glue "buttress," and a program of postoperative activity restriction, the new procedure allowed us to achieve statistically significant improvements in graft retention and surgical outcome, with recurrences dropping from 27 percent to 8 percent. In addition, complete resolution or significant symptomatic improvement occurred in 89 percent of patients with vertigo and/or dizziness and in 84 percent with disequilibrium. We conclude that this new surgical technique is an important addition to the otologic surgeon's arsenal for PLF management.
A wide range of recurrence rates (21% to 47%) for perilymph fistula repairs have been reported in the otology literature. An improved surgical technique developed at the Portland (Ore) Good Samaritan Hospital and Medical Center Neurotology Department was used to repair perilymph fistulas in 58 patients from October 1986 to October 1988. Our recurrence rate was reduced from 27% in a 1982-1985 study to 8% in our study. At 1 year postoperatively, improvements in disequillibrium, dizziness, and vertigo were comparable with results of older surgical techniques. Functional outcomes were also good: 83% of patients returned to normal activities of daily living, and 71% also returned to school or resumed gainful employment outside the home.
A patient with lupus anticoagulant and anticardiolipin antibody developed preeclampsia at 24 weeks' gestation. Therapy with human immunoglobulin (Ig) resulted in stabilization of preeclampsia and suppression of the lupus anticoagulant. Anticardiolipin antibody titers were partially suppressed. Preeclampsia worsened at 32 weeks' gestation, and a healthy infant was delivered. For patients with preeclampsia secondary to lupus anticoagulant before the fetus is viable, human Ig is a potential therapeutic option.
The effect of either prophylactic antibiotic or wound antiseptic on bile bacteriology, wound and other postoperative sepsis has been studied in a controlled prospective randomised trial of 243 patients undergoing biliary surgery at a district general hospital. Wound infection rates were significantly less in patients given intravenous ceftriaxone (1%) at induction of anaesthesia when compared to povidone iodine sprayed into the wound at the completion of surgery (9%) (P = 0.02). In all but one patient infected wounds grew organisms identical to those cultured from the bile. There were also fewer chest and urinary infections in the ceftriaxone group but this was not statistically significant.
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The production of immunologically and biologically active somatomedin activity from isolated myoblasts and fibroblasts from fetal rats of 21 days gestational age was investigated. Myoblast-rich cell populations were derived from primary cultures of dispersed muscle cells by the tendency of myoblasts to become detached from the culture dish in the presence of cytochalasin B. Fibroblasts were obtained from fetal muscle. Culture medium conditioned by exposure to myoblasts for 48 hours produced an increased incorporation of both [35S]sulphate and [3H]thymidine by explants of fetal rat costal cartilage in vitro compared to fresh medium. Myoblast-conditioned medium also contained somatomedin-C-like immunoreactivity which diluted in parallel with partially purified human somatomedin-C (3,271 +/- 446 mU/mg cell protein; mean +/- SEM, seven experiments). Medium conditioned by exposure to fetal rat fibroblasts did not promote isotope uptake by fetal rat cartilage above control values, and contained only low levels of somatomedin-C-like immunoreactivity (343 +/- 89 mU/mg cell protein, three experiments). The release of both somatomedin bioactivity and immunoreactivity into conditioned medium was significantly reduced by the incubation of myoblasts in the presence of rat growth hormone (100 ng/ml and 500 ng/ml). We conclude that fetal rat myoblasts released growth factor activity during culture which exhibited biological and immunologic characteristics of somatomedin. Since the bioactivity was demonstrated on skeletal tissues from rat fetuses of the same gestational age as those that yielded myoblasts such growth factor release may be physiological.
The effect of allergic bronchoconstriction on the permeability of the airway mucosa to large hydrophilic polar solutes was investigated in the guinea pig. After specific antigen (ovalbumin) challenge, there was a significant increase in the plasma levels of horseradish peroxidase (HRP) (molecular weight, approximately 40,000 daltons), 3H-dextran (approximately 10,000 daltons), and 14C-mannitol (approximately 182 daltons) compared with that in control animals aerosol-challenged with a nonspecific protein, lactoglobulin. The morphologic correlates of this enhanced transepithelial permeability after ovalbumin challenge appeared to be (1) increased HRP penetration of the epithelial tight junctions (p less than 0.001), and (2) increased mucus discharge from surface lining goblet cells. We conclude that antigen-induced bronchoconstriction leads to an increase in tracheobronchial permeability to macromolecules, and this effect is likely to be mediated by an increased paracellular as well as transcellular vesicular movement of large polar solutes across the airway epithelial barrier.