Water temperatures influence the marine area use of Salvelinus alpinus and Salmo trutta.

The migratory behaviour and spatial area use of sympatric Arctic charr Salvelinus alpinus and brown trout Salmo trutta were investigated during their marine feeding migration. The likelihood of finding individuals of both species in the inner or outer fjord areas was dependent on water temperature in the inner area (especially for S. alpinus), the temperature difference between the inner and outer areas (especially for S. trutta) and fish fork length (both species). The strongest predictor was the water temperature in the inner area, and particularly S. alpinus left this area and moved to the outer areas with increasing temperatures in the inner area. At 8° C in the inner area, the likelihood of finding S. alpinus in the outer areas was >50%. This predictor had a smaller effect on S. trutta, and the likelihood of finding S. trutta in the outer areas only started to increase at around 14° C. The relationships between temperature and area use did not correspond to the species' optimal growth temperatures, but to their previously documented temperature preferences. Individuals of both species used mainly the littoral fjord areas, and to a lesser extent the pelagic areas. In conclusion, temperature differences between the inner and outer marine areas probably resulted in the segregated area use between the species, because water temperatures or factors influenced by temperature affected their migratory behaviour and habitat use differently. The results indicate that increased marine temperatures with global warming may lead to increased spatial overlap between S. trutta and S. alpinus, which again may lead to increased interspecific competition during their marine phase, and with S. alpinus probably being the more negatively affected.

[Therapy of acute ankle sprain: one-year results of primary conservative treatment]. / Therapie der fibulotalaren Bandverletzung: Ein-Jahres-Ergebnisse nach primär konservativer Behandlung.

INTRODUCTION AND AIM: Ankle sprains (supination-eversion injury) have a high incidence. Conservative treatment is generally the method of choice. This study is intended to evaluate the 1-year results of a standardised treatment protocol. MATERIAL AND METHODS: A total of 416 patients who had suffered an ankle sprain were included into this study. All of them had undergone primary conservative treatment. A total of 66 of them (15.9 %) had undergone operative treatment within one year after injury. The indications for operation were persistent pain, swelling or persistent instability. In 33 patients an arthroscopy for evaluation of the joint and debridement was used. In the case of a persistent instability 22 ligament augmentations (Kuner periostal flap) and 11 peroneus tenodesis (Watson-Jones) were performed. The evaluation was done by using the AOFAS score ("Ankle Hindfoot Scale" of the American Orthopedic Foot and Ankle Society). RESULTS: A 1-year follow-up was possible in 96.4 % of the patients. The mean AOFAS score was 77.1 ± 10.5 points after conservative treatment. Those patients who needed an arthroscopic debridement had a slightly better outcome (AOFAS score 79.5 ± 10.2 points). Patients who had undergone stabilisation operations tended to have the best outcome (p = 0.093). The AOFAS score was 79.6 ± 15.4 points in patients after periostal flap augmentation, respectively, 83.0 ± 7.4 points after peroneus tenodesis. CONCLUSIONS: The results confirm the benefit of conservative treatment in acute ankle sprain. Even so about 15 - 20 % of the patients still suffer from persistent pain, swelling or instability. The indication for operative intervention should be made relatively broadly. Most of these patients profit from the operation. Above all, after ankle sprain patients need a continuous re-evaluation by a specialised centre during the first post-injury year.

Gonadal regulation of gonadotropin subunit gene expression: evidence for regulation of follicle-stimulating hormone-beta messenger ribonucleic acid by nonsteroidal hormones in female rats.

Gonadectomy results in a rise in gonadotropin secretion and subunit gene expression, although the relative contributions of declining gonadal hormones or increasing hypothalamic GnRH secretion are uncertain. To further delineate the roles of the hypothalamus and gonads in regulation of gonadotropin gene expression, male and female rats were castrated and gonadotropin subunit messenger RNA (mRNA) concentrations measured 2, 7, 14, or 21 days (d) later. In males, FSH beta mRNA was maximal (2-fold increase) by 7 d while peak levels of alpha (3-fold) and LH beta (3-fold) were seen by 14 d. Testosterone (T) replacement restored all three subunit mRNA concentrations to intact values. In females, FSH beta mRNA also reached plateau levels (8-fold increase) earlier than alpha (3-fold) or LH beta (11-fold). When female rats ovariectomized 7 days earlier were given estradiol (E2) and progesterone (P) implants for up to 14 d, suppression of alpha and LH beta to intact levels was observed. However, FSH beta mRNA concentrations only decreased to 67% of castrate values, and remained 2- to 3-fold higher than levels in intact female rats. Female rats were also given E2 replacement at the time of ovariectomy. LH beta mRNA was maintained at intact levels for 14 days while alpha and FSH beta showed partial castration responses (2-fold and 3-fold, respectively). Finally, to determine whether E2 and P regulate gonadotropin subunit expression directly or by reducing GnRH secretion, female rats were ovariectomized and immediately replaced with E2, P, or E2 + P in the presence or absence of a GnRH antagonist (A) for 2 d. alpha mRNA was increased (2-fold) by E2 but not by E2 + A suggesting that E2 requires the presence of GnRH to increase alpha mRNA. P alone was ineffective, but both E2 and A prevented the LH beta mRNA response to ovariectomy. The effects of E2 and A were not additive, suggesting that E suppresses LH beta mRNA by inhibiting the increase in GnRH secretion. In contrast, the FSH beta mRNA response to ovariectomy was only partially suppressed by E2, E2 + P, or E2 + P + A. These data indicate that in castrate males, replacement of T suppresses all three subunit mRNAs to intact levels. However, replacement of E2 to ovariectomized females did not prevent the increase in alpha and FSH beta mRNAs. In female rats, LH beta mRNA is predominantly regulated by GnRH. alpha mRNA expression is also mainly regulated by GnRH, and E2 appears to augment GnRH action on alpha mRNA expression.(ABSTRACT TRUNCATED AT 400 WORDS)