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I 2000/2001 er der blevet arbejdet på tværs af de danske arkitekt- og designskoler med det mål at skabe visioner om 'Fremtidens bolig.' Det er sket i en prisopgave, der krævede en særlig stillingtagen til bæredygtighed og tilgængelighed. Prisopgaven indledtes med en række seminarer, hvor ind- og udlandske forelæsere gav deres bud på det at bo i fremtiden. I denne bog præsenteres de væsentligste foredrag sammen med prisopgavens resultater.

Som en reaktion mod den postmodernistiske arkitektur har vi i de seneste år været vidne til en arkitektonisk nydannelse. Den har i sit udtryk meget til fælles med modernismens arkitektur. De hvide facader, de gennemgående vinduesbånd, fraværet af ornamentik og det minimalistiske udtryk er blot nogen af de træk, der leder tankerne tilbage til mellemkrigsårenes arkitektur. Men er der reelt tale om et brud med postmodernismen? Eller udspiller den nye udgave af modernismen sig udelukkende på billedplanet? Er dens værdigrundlag således langt fra modernismens? Er der med andre ord tale om en fortsættelse af postmodernismen eller modernismens genkomst? Disse spørgsmål søger en række ind- og udenlandske arkitekturteoretikere at give svar på i denne antologi.

En del af de renoveringer, der siden midt i firserne har fundet sted i en række nyere, almennyttige bebyggelser, er karakteristiske ved deres overfladiske forandringer som f.eks. bemalinger. Men der er også eksempler på mere grundlæggende opgør med de problemer, bebyggelserne havde inden renoveringen. De mest vellykkede renoveringer har rødder i den oprindelige arkitektur. Denne rapport viser - og diskuterer - 23 bemærkelsesværdige eksempler på renoverede boligområder. Rapporten rummer en række anbefalinger, der kan opstilles for kommende byggesager, samt nogle råd, der retter sig mod de enkelte bygningsdele: Facader og gavle, tage, altaner, indgangspartier, udearealer og økologiske hensyn. Rapporten henvender sig til boligselskaber og ansvarlige for kommende renoveringer.

The aim of the study was to determine the effect of parathyroid hormone (PTH), the antiresorptive agents estrogen and bisphosphonate (risedronate), and also the combination of PTH with these antiresorptive drugs on femoral cortical bone mass, dimensions and strength in a sexually mature, ovariectomized rat model. A total of 138, 3-month-old Sprague-Dawley rats were randomized into seven groups: 1--sham operated (control); 2--ovariectomized (OVX); 3--OVX plus estrogen; 4--OVX plus bisphosphonate (risedronate [NE]; 5--OVX plus hPTH (1-34); 6--OVX plus hPTH (1-34) and estrogen; 7--OVX plus hPTH (1-34) and risedronate. Treatment regimens were initiated 4 weeks after OVX and were continued for 5 and 15 weeks for each treatment group. Changes in bone mass (ash content), cross-sectional area, cortical thickness and dimensions and bone strength were assessed in middiaphyseal, femoral specimens. The results revealed that ovariectomy had no effect on cortical bone mass and biomechanical competence. OVX rats treated with estrogen and also OVX rats treated with risedronate showed no significant difference from either OVX or control groups. After only 5 weeks of treatment, hPTH monotherapy increased ash content, cross-sectional area, cortical thickness and compressive bone strength (load) significantly. After 15 weeks of treatment, OVX rats treated with PTH monotherapy or PTH in combination with risedronate showed identical load-values. These values were significantly higher than those seen in both control and OVX rats. However, PTH in combination with estrogen failed to augment cortical bone strength over control or OVX levels after therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

The rat model has previously been used to test the effect of ovariectomy and of PTH administration on vertebral bone mass, size, and biomechanical competence. In this study, we used the same "biomechanical rat model" to assess the effect of long-term exercise on vertebral bone mass and quality and also on femoral bone mass, dimensions, and strength. Sixty female Fischer rats were randomized into four groups. Two groups were exercised for 5 days a week on a treadmill with a running distance of 2 km per day. The exercise program was initiated at the age of 2 months. The two exercise groups were investigated after 4 and 10 months. Two sedentary groups (observed for 4 and 10 months) served as controls. At death, three lumbar vertebral bodies (L4-L6) and the left femur were obtained from each rat, and changes in bone mass (ash density, trabecular bone volume [BV/TV]), bone size, and biomechanical competence were assessed. The results revealed an age-related (4-10 months) increase in vertebral bone mass and strength. The additional effect of exercise on the vertebral bodies was an increase in cross-sectional area and bone biomechanical competence. In the femoral bone specimens, an age-related increase in bone mass, size, and strength was also disclosed, and while exercise by itself had no significant influence on biomechanical parameters it did reduce cortical-endosteal bone resorption. The study has demonstrated an anabolic effect of a light exercise regimen on both femoral cortical bone and vertebral bodies (mainly trabecular bone).(ABSTRACT TRUNCATED AT 250 WORDS)

The ovariectomized rat model has now been generally accepted as a useful model for screening different therapeutic agents, but there is a major requirement to identify reliable large animal models for osteoporosis research. In this study, the calcium restricted, ovariectomized minipig has been thoroughly investigated in order to define a large animal model with trabecular and cortical bone remodeling which would be reliable for further testing of agents that had shown promise of efficacy during the screening procedure. Twenty six female, 4-month old minipigs were randomized into four groups and fed either normal diet (0.90% calcium (Ca.)) or diet with restricted calcium content (0.75%, 0.50%). At the age of ten months, 3 groups were ovariectomized (OVX) while one group on normal diet was shamoperated. The groups were followed for six months after the operation. At death, bone mass was determined by densitometry and by ashing. Additionally, biomechanical competence was assessed in trabecular bone cores from the vertebral bodies. Finally, histomorphometry (static and dynamic parameters) and structural analyses (star volume) were performed on the vertebral bodies. The study revealed an OVX-related decline of 6% in vertebral bone mineral density (BMD) and a decline of 15% in trabecular bone volume (BV/TV). In contrast, a 15% increase in mean trabecular plate separation (Tb.Sp.) and a small increase in marrow space star volume (Ma. Star V.) were detected. The structural changes became more pronounced when OVX was combined with mild Ca. restriction (0.75% Ca.) with an increase in Ma. Star V. to 164%.(ABSTRACT TRUNCATED AT 250 WORDS)

PTH has a proven anabolic effect on bone mass, as has been shown in several animal models and treatment regimens. The aim of this study was to ascertain whether the positive effect on bone mass is also reflected in the quality of bone formed. The study was performed in a rat model using human PTH (hPTH). One hundred and twenty male Wistar rats, divided into 10 groups, were given either hPTH-(1-34) or hPTH-(1-84) in daily sc doses. Dose levels ranged from 0.11-3.00 nmol/100 g BW.day for a period of 30 days. At death all six lumbar vertebrae were obtained from each rat. A combination of methods was applied to these vertebral bodies in order to ascertain the effect of hPTH on vertebral bone volume, density, trabecular structure, and biomechanical competence. The results revealed a dose-dependent increase in total volume, dry weight, ash weight, and trabecular bone volume. Also, a dose-dependent increase in load values could be demonstrated. The increase in bone strength remained significant after normalization for both cross-sectional area and bone mass. This indicates that the increase in bone size and bone mass was not achieved at the expense of the quality of the bone present. When the two treatments were administered at the same molar dose level, no difference between hPTH-(1-34) and hPTH-(1-84) was revealed. On the basis of this study, it is concluded that PTH could prove to be a promising treatment in the management of osteopenic states.

Udgivelsesdato: 1988-May-1 The interaction between a small dermatan sulphate proteoglycan isolated from human uterine cervix and collagen type I from human and rat skin was investigated by collagen-fibrillogenesis experiments. Collagen fibrillogenesis was initiated by elevation of temperature and pH after addition of proteoglycan, chondroitinase-digested proteoglycan or isolated side chains, and monitored by turbidimetry. Collagen-associated and unbound proteoglycan was determined by enzyme-linked immunosorbent assay after aggregation was complete. (1) The binding of proteoglycan to collagen could be explained by the presence of two mutually non-interacting binding sites, with Ka1 = 1.3 x 10(8) M-1 and Ka2 = 1.3 x 10(6) M-1. The number of binding sites per tropocollagen molecule was n1 = 0.11 and n2 = 1.1. The 0.1 high-affinity binding site per tropocollagen molecule indicates that the strong interaction between proteoglycan and collagen results from a concerted action of tropocollagen molecules in fibrils. Digestion of the proteoglycan with chondroitinase ABC did not affect these binding characteristics. (2) Proteoglycan did not affect the rate of fibrillogenesis, but increased the steady-state A400 by up to 90%. This increase was directly proportional to the saturation of the high-affinity type of binding sites. Neither isolated core protein nor isolated side chains induced a similar high increase in steady-state A400. (3) Electron micrographs showed that the fibril diameter was affected only to a minor extent, if at all, by the proteoglycan, whereas bundles of laterally aligned fibrils were common in the presence of proteoglycan. (4) Results obtained with human and rat collagen were similar.