Factors related to renal haemodynamics in young type-1 diabetes mellitus patients

The influence of metabolic control (HbA_1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA_1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA_1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA_1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients.     

Anabolic and catabolic hormonal response of elite runners to training at high altitude

A 2-week training period 2000 meters above sea level performed by 6 male elite Swedish runners influenced neither basal anabolic (total and non-sex hormone-binding globulin (SHBG)-bound testosterone (NST) and insulin-like growth factor-1 (IGF-1) nor catabolic (cortisol) hormones when comparing serum levels prior to and after the training camp. The anabolic vs catabolic hormone balance, expressed as the NST: cortisol ratio, also remained unchanged as well as SHBG and body mass. Thus, training at 2000 meters above sea level, often practised by elite runners to improve performance in competition at sea level, does not result in a catabolic situation after return to sea level, as measured by peripheral hormones. However, the adaptation to high altitude was associated with a slight (NS) decrease in testosterone as well as in anabolic vs catabolic balance as measured the third day at high altitude. Simultaneously, a decrease in subjective performance was claimed by the runners, but could not be shown by objective measurements. From day 3 to day 9 at high altitude, all runners claimed a subjective recuperation of performance. Total and non-SHBG-bound testosterone increased significantly from day 3 at high altitude to the first post-camp sea-level test. The results reflect the necessity of adaptation when travelling to races at different altitudes. The Swedish runners had significantly higher cortisol, total testosterone and NST levels compared with basal values of a group of 17 elite Kenyan runners living and training at high altitude. Since the NST cortisol and IGF-1 values were not lower, a catabolic state or malnutrition was not likely to be present. The results might reflect an adaptation to altitude or ethnic variations.     

Healing-in of root analogue titanium implants placed in extraction sockets. An experimental study in the beagle dog.

The aim of these animal experiments was to characterize and evaluate the healing-in of root analogue titanium implants fitting with high precision to the alveolar wall. Four beagle dogs were used in the study. The roots of the 3rd and 4th mandibular premolars in both quadrants of 3 dogs and in 1 quadrant of 1 dog (dog 4) were extracted after hemisection. Each root was machine-copied to 1 titanium analogue. In dog 4, however, 2 titanium analogues were fabricated from each of the 4 extracted roots. This enabled insertion of analogues also into the contralateral sockets obtained by extraction of the corresponding roots immediately before implant installation, which was undertaken 2 weeks after the first extractions. Thus, in all, 32 analogues were implanted in their respective (or contralateral) sockets following ridge incision and elevation of mucoperiosteal flaps. The analogues were carefully covered by the repositioned flaps. In dog 4, 2 analogues from the immediate sockets and 2 from the 2-week sockets were surgically exposed and supplied with titanium crowns after a healing period of 2 months. The healing after implantation was evaluated by clinical, radiographic and histological measures after 2, 12 or 36 months. Two analogues (6%) were lost due to early (during the 1st week) exposure to the oral cavity. Another 2 analogues (6%) were, although not exposed, encapsulated by soft tissue and were easily removed with a surgical forceps. Twenty-eight analogues (88%) were healed-in by contact between bone and implant (osseointegration).(ABSTRACT TRUNCATED AT 250 WORDS)     

Systemic effects of two nasally administered glucocorticosteroids

Two topical corticosteroids, budesonide (BUD) and beclomethasone dipropionate (BDP), both administered as suspensions in water, were investigated in healthy volunteers regarding influence on cortisol in plasma and urine (U-cortisol) after nasal application. In the first study, single doses of 200, 400, and 800 μg of BDP and BUD were given at 10:00 pm. In the second study, 100, 200, and 400 μg were given mornings and evenings for 4 days. In the single-dose study, none of the drugs or doses showed any significant influence on cortisol in plasma. However, U-cortisol decreased significantly after BUD 400 and 800 μg. In the multidose study, U-cortisol values were significantly reduced after all doses of BUD and the highest dose of BDP. The compounds tested showed different ability to cause measurable systemic effects after nasal application. The clinical implication is that the prescriber, when choosing a compound, should take the application site into consideration and should also be encouraged to find the lowest effective dose.     

Improved long-term bone-implant integration Experiments in transgenic mice overexpressing bovine growth hormone

Several recent studies have investigated the effects of growth hormone (GH) on the healing of fractures and bone ingrowth, but with conflicting results. The negative results may be due to antibody formation against injected GH or because some experimental models are able to prove only positive GH effects. In this study, we wanted to investigate the effect of GH on implant integration in bone. To avoid potential formation of antibodies against injected GH, we used a model with transgenic mice overexpressing bovine GH (bGH).

Titanium implants were inserted in the forehead of the mice. 4 months after insertion, the implants were cut out en bloc with the surrounding bone. The calcified specimens were cut and ground to a thickness of approximately 10m. Histomorphometry demonstrated significantly more direct bone-to-metal contact in the transgenic mice than in the nontransgenic littermates. Our findings indicate that systemic administration of GH in humans may improve implant integration in bone.