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D Kuhn

Publications and source records attributed to D Kuhn.

At least 19 recordsLinked to original sources
PubMed2006

Streamlined models of dementia care mapping.

Dementia Care Mapping (DCM) is an observational tool that provides rich data about the quality of life and quality of care of persons with dementia in group care settings. The method is time-consuming and thus costly to implement in practice. This paper presents an attempt to 'streamline' DCM for the sake of simplifying it and reducing the financial resources required to implement it. Data were collected for 166 persons with dementia in three types of care settings. Seven streamlined time-sampling models were tested against the original DCM model. In general, results support the use of certain models for specific purposes. The strengths and limitations of these streamlined models are discussed and recommendations are made.

Aged, 80 and over↗
PubMed2004

[Indications for photodynamic therapy in age-related macular degeneration].

Exudative age-related macular degeneration (ARMD) is now benefitting from new therapeutic approaches. Three international randomized clinical trials have demonstrated the efficacy of photodynamic therapy (PDT) in stabilizing visual acuity at 2 years. PDT is based on the activation of a photosensitizer with an adapted wavelength. In age-related macular degeneration, the photosensitizer used is verteporfin (Visudyne), which accumulates preferentially in choroidal new vessels. Functional results are obtained on the basis of a strict classification based on fluorescein angiography examining the type of the new vessels responsible for exudative ARMD. Thus, subfoveal lesions, either predominantly classic (>50%) or occult only, are the indication for PDT. Classic CNVs where laser photocoagulation thermal burns extend into the foveola may be an extrapolation of the indication for PDT. In addition, fluorescein angiography is essential for considering retreatment, usually necessary. Demonstrated growth and the persistence of leakage from the CNV is an absolute indication for a new session of PDT. A number of features still require assessment in order to define the responder group more accurately and to refine and possibly simplify the indications for retreatment.

Choroidal Neovascularization↗
PubMed2004

Influence of cognitive impairment, functional impairment and care setting on dementia care mapping results.

Quality of life (QOL) for people with dementia has become a major focus over the past decade. Dementia care mapping (DCM) is an observational measure of quality of care given by staff in formal care settings, as well as a measure of QOL that has been used in many studies of people with dementia in residential care settings. However, the method itself has not been rigorously studied in a scientific manner. For this report, mapping data were collected for 166 persons with dementia in three types of care settings: special care facilities that are licensed nursing homes, assisted living facilities, and adult day centers. The relationships between DCM and several independent variables including cognitive status, functional status, care setting, depression, length of stay, and co-morbid illnesses were assessed. Both cognitive status and functional status were found to be associated with DCM scores. Moreover, DCM was sensitive in differentiating among persons with four levels of cognitive impairment. Implications for practice are discussed.

Activities of Daily Living↗
PubMed2002

Shorter discharge time after regional or intravenous anaesthesia in combination with laryngeal mask airway compared with balanced anaesthesia with endotracheal intubation.

BACKGROUND AND OBJECTIVE: The efficiency of operating room times can be significantly improved using rapid changes between operative procedures. We performed a retrospective analysis using electronic anaesthesia charts that compared anaesthesia-related times between the three most frequently performed types of anaesthesia (for orthopaedic surgery) to evaluate the potential for a quicker turn-around between cases. METHODS: A total of 5614 anaesthetic procedures in trauma-related orthopaedic surgery were performed from 1997 to 1999. All were documented with an automatic record-keeping system. Data were compared for intravenous anaesthesia with the laryngeal mask airway, balanced anaesthesia with tracheal intubation and regional anaesthesia. The primary outcome measure was the time needed for emergence from anaesthesia after the end of surgery. Statistical evaluation was performed with matched triples for all three types of anaesthesia (155 triples for ambulatory surgery, 249 triples for in-patient care). RESULTS: For ambulatory surgery, the induction time was significantly shorter for general anaesthesia (23.7 min for intravenous anaesthesia, 22.7 min for balanced anaesthesia techniques) compared with regional anaesthesia (27.2 min). The time from the end of the surgical procedure to transfer of the patient out of the operating room was shortest for regional anaesthesia (6.3 min) compared with intravenous anaesthesia (9.0 min) and balanced anaesthesia (12.5 min) techniques. Results were comparable for in-patients: regional anaesthesia required significantly longer for its induction, but less time for patient discharge from the operating room. CONCLUSIONS: The use of a regional anaesthesia technique or one involving intravenous anaesthesia in combination with the laryngeal mask airway may lead to a reduction in discharge time compared with a balanced anaesthesia technique with endotracheal intubation. Thus, improved use of resources may be achieved.

Adult↗
PubMed2002

Mitochondrial DNA restriction map for the Caribbean fruit fly, Anastrepha suspensa, and occurrence of mitochondrial DNA diversity within highly inbred colonies.

A restriction map has been constructed for Anastrepha suspensa mitochondrial DNA. One HaeIII site was found to be polymorphic among individuals in highly inbred colonies and a feral population. Based on mapping information, the polymorphic site was determined to be in the ATPase 6 gene. Primers TK-J-3804 and C3-N-5460 amplified this region. The amplicon was cut by HaeIII in flies of one haplotype and not cut in flies of the other haplotype. From 30 to 43% of the individual flies studied had this additional HaeIlI site. After cloning of the approximately 5200 bp XbaI fragment, the two mitotypes were identified. A 988 base fragment, coding for the entire tRNA-Lys(AAG), tRNA-Asp(GAC), and ATPase 8genes, and a partial ATPase 6gene was sequenced Four silent mutations, including the one at the informative site were located. The HaeIII polymorphism and other sequence differences may prove useful as a diagnostic for identification of the origin of introduced fruit flies.

Animals↗
PubMed2002

[Photodynamic therapy].

Photodynamic therapy with Verteporfine (Visudyne Novartis Ophthalmics) achieves a photo occlusion of subfoveal choroidal neovascularization (CNV) resulting from age-related macular degeneration (AMD) in phase 1 and 2 studies. Thereafter, two international randomized clinical trials evaluated the product's efficacy in term of visual acuity. Eyes with neovascular lesions due to AMD of less than 5,400 micro, in size involving the fovea and presenting well-defined CNV on fluorescein angiography could be included when visual acuity was between 5 and 1/10. Six hundred and nine patients were subsequently randomized either to Verteporfine or to placebo (proportion 2:1). A follow-up of 3 months made it possible to consider retreatment when a fluorescein leakage was observed. Functional and angiographic results demonstrated the efficacy of PDT with Verteporfine in comparison with placebo at each examination during follow-up. A visual acuity decrease of less than 15 letters on ETDRS (or 3 lines or approximately 1.5/10) occured less frequently in the treated group with PDT (61% out of 402 treated eyes compared with 46% of 207 placebo eyes). Subgroup analysis of predominantly well-defined CNV (involving 50% or more of the total of the exsudative lesion) showed even more favourable effects (67% of treated eyes versus 39% of placebo eyes). Conversely, when well-defined CNV extended to a smaller area, the results were not significant. The most frequent side effect was Verteporfine extravasation at the injection site. As dynamic phototherapy with Verteporfine limits the decrease in visual acuity always occurring in the natural history of CNV caused by AMD, it is desirable that patients presenting subfoveal predominantly well-defined lesions benefit from this new treatment approach.

Aging↗
PubMed2001

CDKN2A/p16 inactivation is related to pituitary adenoma type and size.

p16 (CDKN2A, MTS1, INK4A) status at genomic and protein levels was analysed and correlated with clinico-pathological features in 72 pituitary adenomas. Methylation of CpG islands of promoter/exon 1 sequences was found in most gonadotroph, lactotroph, plurihormonal, and null cell adenomas (36 of 44, 82%), but it was rare in somatotroph (1 of 13 cases, 8%) and corticotroph adenomas (1 of 15 cases, 7%). Homozygous CDKN2A deletion was restricted to rare somatotroph (15%) and corticotroph adenomas (13%). Immunohistochemical p16 protein expression was observed in the normal adenohypophysis, whereas it was absent in 60 of 72 (83%) tumours and reduced in another ten (14%) tumours. Staining for p16 was only seen in 5 of 15 (33%) corticotroph, 3 of 13 (23%) somatotroph, 3 of 5 (60%) plurihormonal, and 1 of 19 (5%) null cell adenomas. p16 immunonegativity without CDKN2A methylation or deletion occurred in 22 tumours, including most somatotroph and corticotroph adenomas (15 of 28, 54%). Both CDKN2A alterations and p16 negativity were related to larger tumour size. Patients with p16-negative tumours were older than patients with p16-positive tumours. These data suggest that p16 down-regulation is common in all adenoma types. The mechanisms of p16 down-regulation probably involve CDKN2A methylation in most types, but remain to be determined in somatotroph and corticotroph adenomas. These findings also suggest that p16 down-regulation is usually not an initial event, but is acquired during adenoma progression.

Adenoma↗
PubMed2001

How do people know?

To fully understand processes of knowing and knowledge acquisition, it is necessary to examine people's understanding of their own knowing. Individual and developmental differences in what it means to know something, and hence in the criteria for justifying knowledge claims, have potentially wide-ranging implications. In providing support for a claim, young children have difficulty differentiating explanation of why a claim makes sense and evidence that the claim is true. Epistemic understanding progresses developmentally, but substantial variation remains among adults, with few adults achieving understanding of the complementary strengths and weaknesses of evidence and explanation in argument. Epistemic understanding shapes intellectual values and hence the disposition (as opposed to competence) to exercise intellectual skills. Only its most advanced levels support a disposition to engage in the intellectual effort that reasoned argument entails. The sample case of juror reasoning illustrates how epistemic understanding underlies and shapes intellectual performance.

Cognition↗
PubMed2001

[New therapies for the treatment of age-related macular degeneration].

Age-related macular degeneration has a natural progression from the precursors (the drusen) towards atrophic or neovascular complications. Choroidal neovascularization is undoubtedly the aspect of the disease that benefits most from new therapeutical approaches. Destructive photocoagulation based on fluorescein angiography has demonstrated since 20 years its efficiency on choroidal neovascularization. The same approach based on indocyanine green (ICG) angiography would increase the number of patients available to therapy. Very recently photodynamic therapy has demonstrated its efficiency to stabilize visual acuity at least at two years in patients with choroidal new vessels predominantly well defined. Other treatment developments are considered, such as refinement of photocoagulation techniques or of surgery. Until now, none has demonstrated its efficiency although they raise justified hopes. The future approaches rely upon the progress of the research both in physiopathology of the disease and on the angiogenic process requiring a constant interaction with all thematics of research. Finally, palliative treatments will be required before heading up to a preventive treatment.

Aged↗
PubMed2000

Treatment of recent onset central retinal vein occlusion with intravitreal tissue plasminogen activator: a pilot study.

AIMS: To study the effects of intravitreal tissue plasminogen activator (tPA) in recent onset central retinal vein occlusion (CRVO). METHODS: 15 patients with recent onset CRVO (from 1-21 days' duration, mean 8 days) were given 75-100 microg of tPA intravitreally associate with low dose low molecular weight heparin. CRVO was perfused in nine patients and with mild ischaemia not exceeding 100 disc diameters in six patients. Follow up ranged from 5 to 21 months for 14 patients (mean 8 months). Visual acuity measurement, macular threshold (Humphrey perimeter), fluorescein angiography with the scanning laser ophthalmoscope with special emphasis on retinal circulation times, and retinal perfusion were performed at days 0, 1, and 8 and months 1, 3, and 6. RESULTS: Visual acuity was significantly improved on the first day after treatment in only one eye, and decreased transiently in six eyes (40%). Retinal blood velocity was not significantly modified by tPA injection. Retinal ischaemia developed in six eyes (43%), leading to panretinal photocoagulation in five eyes including one with rubeosis iridis. At the end of follow up, visual acuity had improved to 20/30 or better in five eyes (36%), including two with complete recovery; visual acuity was worse than 20/200 in three eyes (28%). No complication of tPA injection was observed. CONCLUSION: Intravitreal tPA treatment for CRVO appears to be simple and safe, but did not significantly modify the course of the occlusion in our patients immediately after treatment. Final visual outcome did not differ significantly from that observed in the natural course of the disease, but final visual acuity seemed to be slightly better. A randomised study is required to determine if intravitreal tPA actually improves visual outcome in CRVO.

Aged↗
PubMed2000

[Translocation of the macula for retrofoveal choroidal neovascularization in age-related macular degeneration and severe myopia: first results].

BACKGROUND: Subfoveal choroidal neovascularization is a main cause of blindness. The new surgical technique of macular translocation conceived by De Juan, with scleral shortening and without a retinotomy, allows to move the fovea away from the neovascular membrane with a low rate of complications. The first results obtained with this technique are presented here, in cases of submacular neovascularization due to age-related macular degeneration (AMD) or degenerative myopia. PATIENTS AND METHODS: The first 10 patients who were operated on with this technique presented with subfoveal neovascularization due to AMD (6 eyes) or myopia (4 eyes). The time period between the beginning of the disease and surgery was less than 3 months. Before and after surgery, a complete examination included fluorescein and ICG angiographies and OCT. RESULTS: Visual acuity improved by 2 lines or more in 6 eyes (60%), was unchanged in 3 eyes (30%) and decreased in 1 eye. The improvement in vision seemed higher in myopia than in ARMD. Conversely, the mean foveal displacement was greater in ARMD than in myopia (1.2 disc diameter and 0.5 respectively). Laser photocoagulation has been performed in all patients after surgery. Main complications were retinal detachment (1 eye) and neovascularization at the site of transretinal injection (1 eye). Mean follow-up was 3 months. COMMENTS: Macular translocation with the technique described by De Juan allowed visual improvement in more than the half of the eyes with subfoveal neovascularization, resulting in a moderate rate of complications. Long term follow-up is necessary to confirm these results.

Age Factors↗
PubMed1999

Intrasellar malignant lymphoma developing within pituitary adenoma.

A mixed lymphoblastic T cell lymphoma and gonadotroph cell pituitary adenoma occurred 25 years after first resection of the adenoma. Within 1 year the lymphoma overgrew the adenoma, but was still restricted to the sellar region. Histologically, lymphoma and adenoma components were tightly admixed. Possible pathogenetic pathways for intra-adenomatous lymphoma development include monoclonal expansion of T cell infiltrates, expression of adhesion molecules specific for adenoma endothelium, and production of mitogenic pituitary hormones.

Adenoma↗
PubMed1999

Collection of peripheral blood progenitor cells (PBPC) based on a rising WBC and platelet count significantly increases the number of CD34+ cells.

The kinetics of mobilization and optimal timing of peripheral blood progenitor cell (PBPC) collection were evaluated in 190 patients with multiple myeloma undergoing stem cell harvest after mobilization with cyclophosphamide, prednisone and G-CSF. There was a strong correlation between the WBC count and the number of CD34+ cells circulating in peripheral blood (r = 0.875). Initiating leukapheresis based on rising WBC and platelet counts rather than on a fixed day increased the mean number of CD34+ cells 115% (9.7 to 20.9 x 10(6) CD34+ cells/kg; P = 0.010) for the total of all leukaphereses and 59% for the total of all CD34-selected products (5.1 to 8.1 x 10(6) CD34+ cells/kg; P = 0.011). Although the yield and purity of the CD34-selected product were not significantly affected (P > or = 0.071), the percentage of patients with concentrations of CD34+ cells in the initial leukapheresis of > 1% increased from 47% to 70% (P = 0.004). The mean purity of the selected product was related to the starting percentage: 48.9% if < 1% and 81.5% if > or = 1% (P < 0.001). Collection of stem cells based on rising WBC and platelet counts significantly increased the number of CD34+ cells in leukaphereses and CD34-selected products in comparison with collection on a fixed day.

Adult↗
PubMed1999

[Ocular complications of hormonal treatments: oral contraception and menopausal hormonal replacement therapy].

Numerous reports have described ocular complications of sex hormone preparations, particularly after the appearance of the oral contraceptive pill. The most serious complications are vascular occlusions such as central retinal vein or artery occlusion and acute ischemic optic neuropathy. In these cases, permanent visual loss may occur. Combined oral contraceptives have been reported to increase the incidence of these complications but it remains very low. It seems to lessen with the decrease in the estrogen dosage and the use of third-generation progestins. Conversely, post-menopausal hormone replacement therapy seems to have a protective effect for retinal vascular complications. Other ocular involvements have been described with sex hormone preparations but remain not yet confirmed, such as the effect on cataract, lacrymal secretion, diabetic retinopathy, age-related macular degeneration.

Cataract↗
PubMed1996

Circulating adhesion molecules in the critically ill: a comparison between trauma and sepsis patients.

OBJECTIVE: The time course of circulating adhesion molecules was monitored in traumatized and sepsis patients. DESIGN: Prospective, descriptive. SETTING: A surgical intensive care unit of a university hospital. PATIENTS: A total of 30 consecutive critically ill patients suffering either from trauma (n = 15) or postoperative sepsis (n = 15). INTERVENTIONS: All patients were on continuous analgo-sedation and mechanical ventilation. MEASUREMENTS AND RESULTS: From arterial blood samples, plasma levels of soluble adhesion molecules [endothelial leukocyte adhesion molecules (sELAM-1), intercellular adhesion molecule-1 (sICAM-1)], and vascular cell adhesion molecule-1 (sVCAM-1) were measured on the day of admission (trauma patients) or on the day of diagnosis of sepsis (= baseline values), and during the following 5 days. In the trauma group, sELAM-1 (57.9 +/- 11.0 ng/ml) and sVCAM-1 (698 +/- 93 ng/ml) were within normal ranges at baseline, whereas they were markedly elevated in the sepsis group (sELAM-1: 340 +/- 95 ng/ml; sVCAM-1; 1,042 +/- 449 ng/ml). In the sepsis patients, sELAM-1 significantly decreased and sVCAM-1 increased, but remained almost unchanged in the trauma patients. Non-survivors showed markedly elevated plasma levels of sELAM-1 and sVCAM-1. sICAM-1 was elevated in both groups at baseline and was higher in the sepsis group (1,266 +/- 261 ng/ml) than in the trauma group. In the septic patients, sICAM-1 increased further (2,022 +/- 609 ng/ml) and remained unchanged in the trauma group. All non-survivors showed sICAM-1 plasma levels of > 800 ng/ml. CONCLUSIONS: Endothelial damage may result in multiple-organ dysfunction syndrome. Adhesion molecules are considered to be a cornerstone in this process. Trauma patients showed lower plasma levels of circulating adhesion molecules than did sepsis patients indicating more pronounced (inflammatory related) endothelial activation or damage in sepsis. Therapeutic modulation of circulating adhesion molecules may be of benefit to the patients outcome and therefore warrants further study.

Adult↗
PubMed1996

Indocyanine green angiographic features of pathologic myopia.

PURPOSE: To analyze indocyanine green angiographic findings of pathologic myopia and compare them with those of fluorescein angiography, with particular reference to the usefulness of indocyanine green angiography in the management of neovascular complications. METHODS: Thirty-two consecutive patients (52 eyes) with pathologic myopia underwent a complete ophthalmologic examination including fluorescein and indocyanine green angiography. RESULTS: Retrobulbar arteries and veins were visualized solely on indocyanine green angiography in 33 (63%) of 52 eyes. Choroidal arteries appeared attenuated and reduced in number. In the area of staphyloma, choroidal veins were less numerous, and in all eyes an absence of the normal choroidal flush caused by the choriocapillaris filling was observed. Subretinal and retinal hemorrhages were present in 28 (54%) of 52 eyes. Choroidal neovascularization was diagnosed in 16 eyes on fluorescein angiography and in 18 eyes on indocyanine green angiography. In seven eyes, indocyanine green angiography disclosed lacquer cracks (without choroidal neovascularization), appearing in the late phases as hypofluorescent lines, as the probable cause of the subretinal and retinal hemorrhages. In only one eye did indocyanine green angiography fail to disclose choroidal neovascularization detectable on fluorescein angiography. In two eyes, neither dye could clarify the origin of the hemorrhages. CONCLUSIONS: Indocyanine green angiography allows identification of retrobulbar arteries and veins, and analysis of the altered choroidal vasculature. Moreover, indocyanine green angiography is a useful diagnostic tool to differentiate lacquer cracks from choroidal neovascularization in retinal and subretinal hemorrhages.

Adolescent↗