Improved Bone Biomechanical Properties in Rats after Oral Xylitol Administration

The effects of 5, 10, and 20% dietary xylitol supplementations on the biomechanical properties, histological architecture, and the contents of collagen, pyridinoline, and deoxypyridinoline in long bones of rats were studied. Tibiae were used for the three-point bending test, and femurs were used for the torsion and loading test of the femoral neck. The 10 and 20% oral xylitol administrations caused a significant increase of tibial stress, femoral shear stress, and stress of the femoral neck as compared with the controls. Parallel, but not significant, effects were also seen in the 5% xylitol supplementation group. No significant differences in strain or Young's modulus of the tibiae were detected between the groups. An increased shear modulus of elasticity in femurs was detected in the 20% supplementation group as compared with the controls. The histomorphometrical data for the secondary spongiosa of the proximal tibia revealed that trabecular bone volume was significantly greater in all dietary xylitol supplementation groups as compared with the controls. The bone volume increased along with increasing xylitol content. No significant differences between the groups were detected concerning the amount of collagen per dry weight of organic matrix, the concentrations of pyridinoline or deoxypyridinoline in collagen, or the ratio of these crosslinks. This suggests no xylitol-dependent selective changes in these structures of bone collagen. In conclusion, dietary xylitol supplementation in rats improves the biomechanical properties of bone and increases the trabecular bone volume dose dependently. Received: 30 January 1997 / Accepted: 1 October 1998     

The Effect of 3'-Deoxyadenosine N1-Oxide on Growth in Vitro and in vivo on Ehrlich Ascites Tumor and on a Human Squamous Lung Cell Carcinoma Xenograft in Nude Mice

The effect of 3'-deoxyadenosine N¹-oxide (3'-dANO) on Ehrlich ascites tumor and a human squamous lung cell carcinoma was investigated. The 3'-dANO concentration that inhibited the cell growth 50% (IC₅₀) in Ehrlich ascites tumor cells in vitro was 0.15 mM, and the killing efficiency concentration (concentration of the drug that kills all cells) was 1 mM. By simultaneous administration of 3'-dANO and the adenosine deaminase inhibitor erythro-9-(2-hydroxyl-3-nonyl) adenine (EHNA), the IC₅₀ of 3'-dANO was unchanged, but the killing efficiency concentration of 3'-dANO was reduced to 0.3 mM. When mice bearing Ehrlich ascites tumor were treated i.p. with 3'-dANO doses of 200 mg/kg daily for 4 days, the mean increased life span (ILS) was 200%. 3'-dANO in combination with EHNA did not further increase the life span of the tumor-bearing mice. The specific growth delay (SGD) of the Ehrlich tumor and of a human squamous lung cell carcinoma growing subcutaneously in 3'-dANO-treated mice were calculatedfrom Gomperts tumor growth curves. The Ehrlich tumor-bearing mice received 3'-dANO i.p. at doses of 250 mg/kg daily for 4 days, and the nude mice bearing human carcinoma received 3'-dANO i.p. at doses of 225 mg/kg daily for 5 days. The SGD for the investigated tumors were calculated to be 1.0 and 1.1, respectively.     

Congenital cytomegalovirus infection and sensorineural hearing loss

In a prospective study still in progress, infants with congenital cytomegalovirus (CMV) infection were followed with audiological, ophthalmological, neurological, and psychological tests; 10,328 infants were investigated within a 5-year period (1977-1982) by virus isolation in urine within the first week of life. Fifty (0.5%) had a congenital CMV infection. In this group four children turned out to have total deafness and a fifth possibly a mild hearing disorder. In one case the deafness was associated with severe mental retardation and spastic tetraplegia. The mother of the child had a primary CMV infection in the first trimester. In one of the other cases of severe deafness it could be proven that the mother had had a secondary CMV infection and in further two cases, presumed secondary infections. Prospective serological tests of the mothers would not have revealed more than one of the high risk pregnancies. The value of vaccination against congenital CMV infection is questioned. Screening of newborn infants for congenital CMV infection is recommended in order to reveal infants at high risk for deafness and make an early habilitation possible.     

Changing epidemiology of tibial shaft fractures: 513 cases compared between 1971-1975 and 1986-1990

We studied the epidemiological features of tibial shaft fractures during two 5-year periods, 1971-75 and 1986-90 in the county of Uppsala, Sweden. The incidence was higher in men than in women during both periods. In men aged 10-19 years, the fracture incidence was lower during the second period, with a reduction of fractures sustained in road traffic accidents. In women above 80 years, the fracture incidence was higher during the second period.     

Contamination of toothpaste and toothbrush by Streptococcus mutans.

Toothbrushes and toothpaste tubes used by persons infected with S. mutans were examined for the presence of this microorganism. Fifteen minutes after brushing greater than 10(6) S. mutans were isolated from the toothbrushes and after ordinary storage for 24 h 10(4) were recovered. From two out of 10 toothpaste tubes S. mutans was isolated from the orifice of the tube. The implications of these findings for the spread of the microorganism are discussed.     

Longevity after early surgical menopause-the long-term effect of a permanent cessation of reproductive function and female sex hormone loss

OBJECTIVE: To investigate longevity in women after bilateral salpingo-oophorectomy (BSOE), not given hormonal replacement therapy (HRT) post-operatively, as compared to the national mean. STUDY DESIGN: Long-term follow-up study of a historical cohort of young women undergoing BSOE in the early 20th century at the General Hospital, Malm?, Sweden. Comparison was made with mean life expectancy in corresponding birth cohorts. RESULTS: No difference in life expectancy was recorded in 152 women with an early menopause caused by BSOE and not substituted with HRT, as compared to national statistics of contemporary women. Half of the operated women died of cardiovascular disease and a minority of cancer, none of which was a breast cancer. CONCLUSION: Permanent loss of female sex hormones and reproductive function in early life does not seem to influence longevity but may change patterns of morbidity and mortality.     

Muscle strength in children treated for displaced femoral fractures by external fixation: 31 patients compared with 31 matched controls

In a prospective study (1993-2000), we measured the isokinetic strength of the quadriceps and hamstring muscles in 31 children aged 5-17 years, on average, 3 (1.5-5) years after treatment for a displaced femoral fracture by external fixation and early mobilization. A group of age-, sex- and weight-matched children without previous injury were used as controls. The hop-index test was used to assess the patient's confidence in the injured limb and was similar in the fractured and unfractured legs as well as in the patients and controls. We measured the peak torque output at 2 angular velocities (60 degrees/s and 180 degrees/s) in the hamstring and quadriceps muscles, using Cybex testing equipment. Torque to body weight ratios were used to compare muscle strength in patients and controls. We found no differences in muscle strength between patients and controls or in the distribution of which leg was stronger, equal or weaker in the patients or controls at any test speed. External fixation and early mobilization seem to prevent residual muscle weakness, which occurs with traction or a cast for femoral fractures in children.     

The impact of frozen embryos on emotional reactions during in vitro fertilization

BACKGROUND: Emotional reactions of couples were investigated during in vitro fertilization (IVF) at a private clinic in Sweden. The purpose was to compare such reactions between couples who obtained supernumerary embryos that could be cryopreserved and couples without such embryos. METHODS: Forty women and men undergoing IVF treatment monitored individually their emotional reactions daily for one complete treatment cycle from the first day of down-regulation until the outcome of treatment was known. Ratings were extracted and analyzed from two separate days; the very first day of treatment and the day of embryo transfer. RESULTS: The group of women (n=16; 40%) with supernumerary embryos suitable for cryopreservation reported a greater increase in optimism than the group (n=24; 60%) without such embryos (p=0.024). Correspondingly, women with supernumerary embryos reported less pessimism than women without such embryos (p=0.014). Among men there was no difference in optimism or pessimism between the groups. The women and men with supernumerary embryos did not differ in distress reactions compared to those women and men without such embryos. There was no correlation between optimism and distress on the day of embryo transfer in women; r=-0.167 and men; r=-0.135 respectively. CONCLUSION: The presence of frozen embryos increased optimistic and reduced pessimistic feelings about pregnancy among women undergoing IVF treatment. However, the couples' increased optimism on the day of embryo transfer did not seem to reduce their experience of distress.     

Long-term clinical and radiologic results after Eden-Hybbinette operation for anterior instability of the shoulder

A retrospective study was done to assess long-term results after surgery with the Eden-Hybbinette technique for unidirectional anterior glenohumeral instability. Between 1962 and 1976, 118 patients (119 shoulders) were treated. Eighty-seven patients answered a questionnaire. Of 119 shoulders, 77 were examined clinically and 74 radiographically a mean of 29 years after surgery. Forty-two were lost to follow-up. For 74% of shoulders, patients were satisfied, and for 26%, patients had some remaining discomfort. The most common reason for discomfort was persistent instability. The recurrence rate was 20%, although only 8 patients required reoperation. The mean time from surgery until redislocation was 15 months (range, 1-60 months). The mean Rowe shoulder score was 84 +/- 15 (range, 45-100), with 48 of 77 shoulders rated as excellent, 16 of 77 as good, 9 of 77 as fair, and 4 of 77 as poor. The Constant-Murley score averaged 85 +/- 14 (range, 20-100). Glenohumeral arthrosis was seen in 35 of 74 shoulders (47%). There was no significant difference between those with arthrosis and those without as far as age at first dislocation, age at surgery, or follow-up. Shoulders with arthrosis had a tendency to have reduced external rotation (P =.056) when compared with shoulders without radiologic changes. This study showed that most patients were satisfied with their shoulders. There was a high rate of radiologic arthrosis, but in most patients it caused limited restriction of movement as the only symptom.     

Blood perfusion studies on basal cell carcinomas in conjunction with photodynamic therapy and cryotherapy employing laser-Doppler perfusion imaging

Superficial blood perfusion was monitored using laser-Doppler perfusion imaging in connection with a phase III clinical trial comparing photodynamic therapy, utilizing topically applied delta-aminolevulinic acid, with cryotherapy of basal cell carcinomas. A total of 526 images were recorded before and immediately after the treatment and during the follow-up period. Before treatment, the lesions exhibited a blood perfusion 3+/-2 times that in normal tissue. Both treatment modalities induced an increased blood perfusion inside the lesions, which slowly approached normal values in conjunction with successful treatments. The blood perfusion in successfully treated lesions approached normal values 2 months after photodynamic therapy, and about 1 year after cryotherapy. The tissue perfusion in recurrent lesions did not decrease to normal values after the treatment, suggesting that the laser-Doppler perfusion imaging technique can be used to follow the healing process and discover possible persistent tumour growth.