Biomedical subjects

V Kirchner

Publications and source records attributed to V Kirchner.

17 recordsLinked to original sources

PubMed2006

'It's like a revolving door syndrome': professional perspectives on models of access to services for people with early-stage dementia.

As the need for services for people with dementia grows, and the benefits of early intervention become clear, it has become important to understand what factors may improve access to services for people with early-stage dementia. There are a number of models of service access, and these emphasise different areas, whether individual factors, relationships, or social context. The relevance of these models to variations in service access for people with early-stage dementia, and how well they relate to professional accounts, is not well known. In this study, 30 key professionals were interviewed about access to services for people with early-stage dementia in order to explore how different models of access were reflected in their own understandings. People with early-stage dementia were thought to have a range of complex needs, but participants felt these needs remained largely unmet. When articulating the reasons why they thought needs were unmet, participants focused on the impact of the framework within which services are delivered. The findings highlight the importance of considering relationships and socio-contextual factors, such as the impact of the framework of service delivery, when attempting to understand variations in access to services. In order to improve access to services, it will be necessary to move beyond addressing individual factors relating to access, and to consider the impact of the framework for service delivery and the relationships that influence contact with services.

Attitude of Health Personnel↗

PubMed2005

[Anaemia treatment in gynaecology: use of epoetin in onco-gynaecology and gynaecological surgery].

In gynaecology, anaemia treatment is indicated in extremely different situations. In cancer patients, treatment with epoetin can relieve fatigue and improve quality of life. In these patients, epoetin treatment can also have a positive influence on survival through increasing the efficacy of radiotherapy and chemotherapy. Recent data are presented. In gynaecological surgery, the use of epoetin--based on results in oncology and orthopaedic surgery--makes a constructive contribution to the improvement of quality of life and during patient recovery through rapid normalisation of perioperative anaemia, thus reducing the risk of a transfusion with donated blood. Encouraging data from recent publications concerning the prevention of PRCA under epoetin treatment are presented.

Adult↗

PubMed2003

Propentofylline for dementia.

BACKGROUND: Propentofylline is a novel therapeutic agent for dementia that readily crosses the blood-brain barrier and acts by blocking the uptake of adenosine and inhibiting the enzyme phosphodiesterase. In vitro and in vivo its mechanism of action appears to be twofold; it inhibits the production of free radicals and reduces the activation of microglial cells. It therefore interacts with the inflammatory processes that are thought to contribute to dementia, and given its mechanism of action is a possible disease modifying agent rather than a purely symptomatic treatment. OBJECTIVES: To determine the clinical efficacy and safety of propentofylline for people with dementia. SEARCH STRATEGY: The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 5 February 2003. Aventis, the manufacturing pharmaceutical company, was asked for data from unpublished studies but declined to enter into correspondence. SELECTION CRITERIA: Unconfounded double-blind randomized controlled trials of propentofylline compared with a placebo or another treatment group. DATA COLLECTION AND ANALYSIS: There were detailed reports of only four of the nine included studies. The efficacy of propentofylline was reviewed for undifferentiated dementia as there were not enough data to attempt a subgroup analysis for the types of dementia. MAIN RESULTS: The following statistically significant treatment effects in favour of propentofylline are reported. Cognition at 3, 6 and 12 months including MMSE at 12 months. [MD 1.2, 95%CI 0.12 to 2.28, P=0.03] Severity of dementia at 3, 6 and 12 months including CGI at 12 months [MD -0.21, 95%CI -0.39 to -0.03, P=0.03]. Activities of Daily Living (NAB) at 6 and 12 months [MD -1.20, 95%CI -2.22 to -0.18, P=0.02]. Global Assessment (CGI) at 3 months [MD -0.48, 95% CI -0.75 to -0.21, P=0.0006], but not at later times. Tolerability There were minimal data on adverse effects and drop-outs. There were a statistically significant treatment effects in favour of placebo at 12 months, for the number of dropouts, [OR=1.43, 95%CI 1.04 to 1.90, P=0.03]. REVIEWER'S CONCLUSIONS: There is limited evidence that propentofylline might benefit cognition, global function and activities of daily living of people with Alzheimer's disease and/or vascular dementia. The meta-analyses reported here are far from satisfactory as a summary of the efficacy of propentofylline, considering the unpublished information on another 1200 patients in randomized trials that exists. Unfortunately Aventis has been unwilling to correspond with the authors, significantly limiting the scope of this review.

Aged↗

PubMed2001

Electrochemical nanostructuring with ultrashort voltage pulses.

The application of nanosecond voltage pulses to electrodes provides three ways to conduct local electrochemistry on the micro- to nanometer scale. (1) The finite charging time of the double-layer capacity allows the machining of three-dimensional microstructures. (2) In an electrochemical scanning tunneling microscope, reactions are confined to the tunneling region, due to the depletion of the electrolyte in the tip--surface gap. (3) Ordering processes, following very fast electrochemical reactions, lead to unconventional island patterns on a surface.

Electrochemistry↗

PubMed2000

Electrochemical micromachining

The application of ultrashort voltage pulses between a tool electrode and a workpiece in an electrochemical environment allows the three-dimensional machining of conducting materials with submicrometer precision. The principle is based on the finite time constant for double-layer charging, which varies linearly with the local separation between the electrodes. During nanosecond pulses, the electrochemical reactions are confined to electrode regions in close proximity. This technique was used for local etching of copper and silicon as well as for local copper deposition.

Journal Article↗

PubMed2000

Dementia: the cost of care for behaviourally disturbed patients living in the community.

OBJECTIVE: To determine the cost of care of people with dementia and behavioural disturbances living in the community, which is currently unknown. DESIGN, SETTING & PATIENTS: This is a study of 12 randomly selected subjects attending a continuing care dementia day facility for people with behavioural disturbances. MEASURES: Hours of care received from different sources were recorded and costed. RESULTS: The total mean direct costs to the public services was pound400 per person per week. Caregiver's time costed at professional rates were pound1208 per person per week. CONCLUSIONS: Unpaid caregivers supported by publicly funded agencies provide a less expensive service compared to specialised institutional care.

Aged↗

PubMed2000

Thioridazine for dementia.

BACKGROUND: Neuroleptic drugs are controversial treatments in dementia, with evidence accumulating that they may hasten clinical decline. Despite these concerns, they are commonly prescribed for elderly and demented patients. Thioridazine, a phenothiazine neuroleptic, is one of the most commonly prescribed. It has often been a preferred agent because it is thought to produce relatively less frequent motor side effects. The drug has significant sedative effects, and it is thought that these are the main mechanism of action in calming and controlling the patient. However, pharmacologically, it also has marked anticholinergic properties that could potentially have a detrimental effect on cognitive function. OBJECTIVES: To determine the evidence on which the use of thioridazine in dementia is based in terms of: 1) efficacy in controlling symptoms 2) cognitive outcome for the patient 3) safety SEARCH STRATEGY: The Cochrane Controlled Trials Register and other electronic databases were searched using the terms 'thioridazine', 'melleril', 'dementia' and 'old age'. In addition, Novartis, the pharmaceutical company that developed and markets thioridazine, was approached and asked to release any published or unpublished data they had on file. SELECTION CRITERIA: Unconfounded, single-blind or double-blind, randomised trials were identified in which treatment with thioridazine was administered for more than one dose and compared to an alternative intervention in patients with dementia of any aetiology. Trials in which allocation to treatment or comparator were not truly random, or in which treatment allocation was not concealed were reviewed but are not included in the data analysis. DATA COLLECTION AND ANALYSIS: Data were extracted independently by the reviewers (VC, CAK and RJH). For continuous and ordinal variables, the main outcome measures of interest were the final assessment score and the change in score from baseline to the final assessment. The assessment scores were provided by behavioural rating scales, clinical global impression scales, functional assessment scales, psychometric test scores, and frequency and severity of adverse events. Data were pooled where appropriate or possible, and the Peto odds ratio (95%CI) or the weighted mean difference (95%CI) estimated. Where possible, intention to treat data were used. MAIN RESULTS: The meta-analysis showed that, compared with placebo, thioridazine reduced anxiety symptoms as evidenced by changes on the Hamilton Anxiety Scale. However, there was no significant effect on clinical global change, and a non-significant trend for higher adverse effects with thioridazine. Compared to diazepam, thioridazine was superior in terms of some anxiety symptoms, with similar adverse effects. Global clinical evaluation scales mostly did not favour either treatment. Compared to chlormethiazole, thioridazine was significantly inferior when assessed on some items of the CAPE and the Crichton Geriatric Behavioural Rating Scales. Thioridazine was also associated with significantly more dizziness. No superiority for thioridazine was shown in comparisons with etoperidone, loxapine or zuclopenthixol. REVIEWER'S CONCLUSIONS: Very limited data are available to support the use of thioridazine in the treatment of dementia. If thioridazine were not currently in widespread clinical use, there would be inadequate evidence to support its introduction. The only positive effect of thioridazine when compared to placebo is the reduction of anxiety. When compared to placebo, other neuroleptics, and other sedatives it has equal or higher rates of adverse effects. Clinicians should be aware that there is no evidence to support the use of thioridazine in dementia, and its use may expose patients to excess side effects.

Antipsychotic Agents↗

PubMed2000

Enteric parasites in east African immigrants. Symptoms and duration of U.S. residence are not predictive.

The Minnesota Department of Health recommends a health assessment for all refugees within 1 to 3 months of arrival, including screening for enteric parasites. Little information exists, however, to help clinicians decide whether to screen asymptomatic persons who have lived in the United States for a year or more. We questioned 71 immigrants from East Africa now living in Minnesota's Twin Cities about gastrointestinal symptoms and duration of residence in the United States and asked for stool specimens for ova and parasite examination. Fifty-one patients (72%) returned specimens. The prevalence of symptoms was no different in the 14 patients with pathogenic parasites than in the 37 without (71% vs. 76%). Patients with pathogens were likely to have lived in the United States for less time than those without pathogens (median 17 months vs. 32 months), but the groups were not discrete. Clinical data did not identify a group unlikely to have parasites or need screening.

Adolescent↗

PubMed1999

Ki-A10, a germ cell nuclear antigen retained in a subset of germ cell-derived tumors.

Monoclonal antibody Ki-A10 recognizes a nuclear antigen of 25 and 22 kd apparent molecular mass, which is abundantly expressed by immature gonocytes, spermatogonia, and spermatocytes, whereas it is absent in spermatids, spermatozoa, oocytes, and normal somatic tissues. In a broad spectrum of human cancers the antibody showed no reactivity except for a small subset of malignant lymphomas. Because of this restricted expression pattern, we examined 173 germ cell tumors and 18 sex cord stromal tumors immunohistochemically to assess the distribution of the Ki-A10 antigen. A strongly positive reaction was found in classic seminomas, dysgerminomas, spermatocytic seminomas, and the germ cell component of gonadoblastomas. Yolk sac tumors presented a heterogeneous reactivity pattern ranging from overall positivity to complete lack of antigen expression, and in three of eight choriocarcinomas, a few clusters of cytotrophoblast cells were strongly labeled. All other tumors, including Leydig and Sertoli cell tumors as well as placental tissue, were negative. Our findings suggest that specific germ cell antigens can be retained in germ cell tumors along particular differentiation pathways. Ki-A10 is the first marker that consistently labels spermatocytic seminoma, further confirming its germ cell origin and suggesting a close relationship to classic seminoma. The antibody may serve for diagnostic purposes and promises new insights into the process of germ cell differentiation and the development of germ cell-derived neoplasia.

Animals↗

PubMed1998

Selective serotonin reuptake inhibitors and hyponatraemia: review and proposed mechanisms in the elderly.

The association between selective serotonin reuptake inhibitors (SSRIs) and hyponatraemia has been well documented, the elderly appearing to be at greatest risk. An analysis of data of hyponatraemia in the elderly using SSRIs from all published cases and from the Committee on Safety of Medicines found that the mean time to detection was about 3 weeks after commencing SSRIs. A wide range of time to detection (1-253 days) and non-specific symptoms suggest hyponatraemia is detected by chance rather than being specifically looked for. In the elderly there are physiological changes, a high prevalence of medical illnesses and concomitant drug use, which may precipitate hyponatraemia. Together with a risk of altered water regulation in psychiatric illness this may account for the particular susceptibility of the elderly to hyponatraemia whilst using SSRIs.

Aged↗

PubMed1997

A double-blind crossover study comparing prophylactic intravenous granisetron alone or in combination with dexamethasone as antiemetic treatment in controlling nausea and vomiting associated with chemotherapy.

The efficacies of granisetron plus dexamethasone and granisetron alone in controlling nausea and vomiting during two consecutive cycles of moderately emetogenic chemotherapy given for up to 5 days were compared in a two-centre, randomised, double-blind, placebo-controlled crossover study. In all, 110 evaluable patients received either dexamethasone, 20 mg i.v., or matching placebo, plus open-label granisetron, 3 mg i.v., given on each chemotherapy day. At cycle 2, patients crossed over to the alternative treatment; 72 patients completed the crossover. In these 72 patients, the complete response rates over 24 h for granisetron plus dexamethasone and granisetron plus placebo in cycle 1 were 87% and 70% (ns), respectively. In cycle 2 the complete response rates over 24 h were 73% and 62% (ns). Combining the two cycles, the complete response rates over 24 h were 80.6% (granisetron plus dexamethasone) and 65.3% (granisetron plus placebo; P = 0.015). Granisetron plus dexamethasone was significantly more effective in terms of times to less than complete response (P = 0.041), to first episode of moderate/severe nausea (P = 0.04), to first episode of vomiting (0.03) and to use of rescue medication (P = 0.02). Adverse events tended to be minor, with asthenia and insomnia the most common. Of those patients who expressed a preference, 67% preferred granisetron plus dexamethasone (P < 0.05). A single dose of dexamethasone added to granisetron thus enhances the efficacy of granisetron alone in preventing nausea and vomiting after moderately emetogenic chemotherapy.

Adolescent↗

PubMed1996

Structure elucidation of three triterpene glycosides from the trunk of Argania spinosa.

The structures of three novel saponins from Argania spinosa, named arganines G, H, and J, have been elucidated by MS and NMR techniques as 3-O-beta-D-apiofuranosyl- (1-->4)-beta-D-glucopyranosyl-28-O-beta-D-glucopyranosylbayogenin (1), 3-O-beta-D-apiofuranosyl-(1-->4)-beta-D-glucopyranosyl-28-O-alpha- L- arabinopyranosylbayogenin (2), and 3-O-beta-D-apiofuranosyl-(1-->4)-beta-D-glucopyranosyl-28-O- [beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L - rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]bayogenin (3), respectively.

Carbohydrate Sequence↗

PubMed1994

The incidence of anticipatory nausea and vomiting after repeat cycle chemotherapy: the effect of granisetron.

Anticipatory nausea and vomiting (ANV) after repeated cycles of cytotoxic chemotherapy is thought to be a conditioned response to a conditioning stimulus. Good control of acute and delayed emesis may result in a lower incidence of ANV. We have analysed data from 574 chemotherapy patients who received granisetron as their antiemetic treatment during repeat cycle chemotherapy. Per treatment cycle, less than 10% of patients displayed symptoms of anticipatory nausea and 2% or less had symptoms of anticipatory vomiting. It is concluded that the use of granisetron as an antiemetic during the acute phase of chemotherapy may result in a lower incidence of ANV in patients undergoing repeat cycle chemotherapy.

Female↗

PubMed1994

Ondansetron plus dexamethasone is superior to ondansetron alone in the prevention of emesis in chemotherapy-naive and previously treated patients. Swiss Group for Clinical Cancer Research (SAKK).

BACKGROUND: This prospective, randomized, double-blind study assessed whether the addition of dexamethasone to ondansetron leads to improved control of chemotherapy--induced emesis, both in patients undergoing their first course of highly emetogenic chemotherapy and in chemotherapy-pretreated patients refractory to standard anti-emetics. PATIENTS AND METHODS: Patients were randomized to receive either 20 mg dexamethasone as an intravenous infusion or placebo plus ondansetron 8 mg 15 minutes prior to and 4 and 8 hours after the administration of chemotherapy. According to the randomisation code patients received from day 2 to day 5 either ondansetron 8 mg p.o. + placebo p.o., three times daily, or ondansetron 8 mg p.o. + dexamethasone 4 mg p.o., three times daily. Patients undergoing multiple-day treatment received intravenous study treatment on the days of chemotherapy and thereafter oral treatment as outlined above. RESULTS: A total of 215 patients were entered into the study. Of these, 207 were evaluable (111 previously-untreated and 96 previously-treated patients). In the chemotherapy-naive patients the combination of ondansetron plus dexamethasone was significantly superior to ondansetron plus placebo in protecting the patients completely from emesis (retching and vomiting) (81% versus 64%, p = 0.04). The mean number of vomiting episodes was significantly lower in the ondansetron-plus-dexamethasone-treated patients than in those receiving ondansetron plus placebo (0.8 versus 2.1, p = 0.03). In this group of patients there was significantly superior protection from emesis on the second day (p-value = 0.04), and a trend towards a better protection on the third and fourth days. On each day the active combination offered better protection from nausea with an approximately 20% difference in favor of ondansetron plus dexamethasone. In the group of established vomiters the combination of ondansetron plus dexamethansone was superior to ondansetron plus placebo in protecting the patients from acute emesis, with 70% versus 48% of the patients being completely protected (p = 0.03). The mean number of vomiting episodes was significantly lower in the ondansetron-plus-dexamethasone-treated-patients than in those receiving ondansetron plus placebo (0.9 versus 2.1, p = 0.02). In the ondansetron-plus-dexamethasone arm 55% of the patients had complete protection from nausea, retching and vomiting compared to 35% in the ondansetron-plus-placebo-treated group (p = 0.05). Overall 22% of the patients (20% in the ondansetron-plus-placebo and 25% in the ondansetron-plus-dexamethasone arm) experienced at least one, usually mild, adverse event. More patients in the ondansetron-plus-dexamethasone arm complained of epigastric pain or burning (8/101 versus 4/112, p-value = 0.16). The difference in patients reporting constipation (6/101 versus 0/112) was highly significant at a p-value of 0.008. CONCLUSIONS: The combination of dexamethasone plus ondansetron is more effective in protecting chemotherapy-naive patients undergoing their first course of highly emetogenic chemotherapy with cisplatin and chemotherapy-pretreated patients refractory to standard antiemetics from chemotherapy-induced nausea and vomiting compared to ondansetron plus placebo.

Adolescent↗

PubMed1993

De novo initiation codon mutation (ATG-->ACG) of the beta-globin gene causing beta-thalassemia in a Swiss family.

Investigation of microcytic anemia with normal ferrous status in two members (father and daughter) of a Swiss family originating from Bern revealed high levels of HbA2 (4%, 7.3%) and HbF (3.2%, 3.1%). Direct sequence analysis of asymmetrically amplified DNA showed the ATG-->ACG mutation in the intiation codon of the beta-globin gene. Heterozygous beta-thalassemia was not found in either of the propositus's parents or in any of his brothers and sisters. Extended restriction fragment length polymorphism haplotyping of the beta chromosomes led us to the conclusion of a recent spontaneous mutation in the paternal germ cell. The results of routine HLA and blood group testing supported the stated paternity. We also found that the intragenic sequence polymorphisms (frameworks) are not always in linkage disequilibrium with the Bam HI polymorphism downstream from the beta-globin gene as previously observed. This is the second family found to carry this initiation codon mutation in the beta-globin gene. Unlike the first reported family, of Yugoslavian origin, our patients have high HbF levels and this in the absence of a C-->T substitution at -158 site 5' to G gamma.

Base Sequence↗

PubMed1993

Early clinical trial of MDL 73.147 EF: a new 5-HT3-receptors antagonist for the prevention of chemotherapy-induced nausea and vomiting.

BACKGROUND: Like MDL 72.222, one of the first selective 5-hydroxytryptamine3 (5-HT3) receptors antagonist discovered, MDL 73.147 EF has been shown to possess antiemetic properties in the ferret model. We conducted a phase I study with MDL 73.147 EF in 31 patients, treated with emetogenic drugs over one to five days (cisplatin, cyclophosphamide, doxorubicin, dacarbazine). PATIENTS AND METHODS: 5 groups of at least 5 patients received rising unit doses of MDL 73.147 EF (10 to 50 mg) intravenously before chemotherapy, with two more doses per day if needed. Nausea was assessed by a patient-completed visual analogue scale and episodes of vomiting recorded by an independent observer. RESULTS: 51.6% of the patients were complete responders on day one and 40% on days two to five. One patient was given other rescue antiemetic therapy. Adverse events included constipation (25.8%), mildly elevated blood pressure (12.9%) and other minor events. No extrapyramidal effects have been reported. There was no suggestion of dose-dependent efficacy at the dose levels studied in this limited set of patients. CONCLUSIONS: We conclude that MDL 73.147 EF is a well tolerated and possibly effective antiemetic.

Adolescent↗

PubMed1993

Clinical studies to assess the economic impact of new therapies: pragmatic approaches to measuring costs.

Pragmatic clinical trials using unselected patients in normal clinical situations are more appropriate for the economic assessment of new drugs. However, standard clinical studies that do not reflect current practice are useful and at present the only source of information. Anti-emetic drug studies using granisetron and ondansetron have demonstrated that the overall economic impact of these drugs is equivalent to standard therapies such as metoclopramide. Thus, an efficient anti-emetic drug with less frequent dosing, using a simplified dosage regimen and producing a reduction in anticipatory nausea and vomiting and in nursing time, may result in an overall reduction in cost. Decisions made purely on the basis of drug costs may be misleading and promote inefficient use of health resources.

Antiemetics↗