Application of the Red List Index as an indicator of habitat change

For the first time ever, the International Union for Conservation of Nature Red List Index for habitat types was calculated for an entire country, Finland. The RLIs were based on species threat assessments from 2000 and 2010 and included habitat definitions for all 10,131 species of 12 organism groups. The RLIs were bootstrapped to track statistically significant changes. The RLI changes of species grouped by habitats were negative for all habitat types except for forests and rural biotopes which showed a stable trend. Trends of beetles and true bugs were positive in rural and forest habitats. Other 16 observed trends of species group and habitat combinations were negative. Several trends observed were in accordance with studies focusing on particular taxa and habitats, and drivers for their change. This study demonstrates the usefulness of the RLI as a tool for observing habitat change based on species threat assessment data.     

Basement membrane and epithelial features of fetal-type Leydig cells in rat and human testis

The basement membranes of developing Leydig cells in fetal and newborn testis of rat were studied by ultrastructural and immunocytochemical methods. Fetal-type Leydig cells in prenatal rats were organized in irregularly outlined groups in the interstitium and were extensively surrounded by ultrastructurally identifiable basement membranes and immunocytochemically localized laminin and collagen type IV. Prenatal Leydig cell precursors had small patches of laminin and collagen type IV on their surfaces, which indicated that changes in extracellular matrix took place during their differentiation to mature fetal-type Leydig cells. Additionally, ultrastructural evidence was obtained for a basement membrane surrounding the fetal human Leydig cells similar to that in fetal rats. Soon after birth the rat fetal-type cells gathered into distinct clusters surrounded by delicate envelope cells and a discontinuous basement membrane. Basement-membrane structures, laminin, and collagen type IV were observed between the clustered cells as well. The basement membranes covering large cell surface areas of the fetal-type Leydig cells in fetal and newborn rats differed from those of the adult-type cells, which, according to our earlier study, are covered only by small patches of basement membrane. The difference between the basement membranes of the fetal- and adult-type rat Leydig cells further supports the concept of two different Leydig cell populations. The earlier findings of the epithelial nature of the Leydig cells agree with the observation of basement membranes in the Leydig cells.     

Differentiation of smooth muscle cells in the fetal rat testis and ovary: localization of alkaline phosphatase,smooth muscle myosin,F-actin,and desmin

Summary The histochemical demonstration of alkaline phosphatase (AP) activity and localization of smooth muscle myosin (SMM), F-actin, and desmin were carried out on frozen sections of testes and ovaries from 15-day-old fetal to newborn rats. The presence of immunocytochemically localized SMM and desmin was confirmed by Western blot analysis of proteins from isolated gonads. The development of smooth muscle cells was predominant in the testis. The first SMM-positive cells with an increasing intensity for F-actin and desmin appeared in the testicular tunica albuginea and around the testicular cords by the age of 16 days. A continuous layer of SMM- and F-actin-positive (but not uniformly desmin-positive) myoid cells was detected in the newborn testis. In the early gonads and in the newborn ovary, a majority of the interstitial cells expressed desmin, indicating that, in undifferentiated tissues, non-myogenic cells may also express desmin. During fetal development, male and female gonocytes showed a decrease in F-actin content but retained their high AP activity. In the cortex of the newborn rat ovary, the observed high AP activity and the presence of desmin may be associated with the postnatal histogenesis of the follicles. The presence of SMM-containing cells in the hilus of the ovary may be required for the demarcation of the ovary from the mesonephros by the constriction of the mesovarium. The occurrence of SMM-positive cells predominantly in male fetuses suggests that the development of the contractile cells in the fetal testis may be induced by testicular androgens.     

Long-term microtine dynamics in north Fennoscandian tundra: the vole cycle and the lemming chaos

Densities of microtine rodents in two habitat complexes in the tundra of Finnmarks-vidda, Norwegian Lapland, were studied during 1977-89 by means of snap trapping (Small Quadrat Method) Predator populations were studied by mapping breeding raptors and by snow-tracking small mustelids During 1977-85, snow-trackmg was conducted only during peak and decline years, whereas during 1986-89, snow-tracking was conducted every winter (November-December) and live-trapping (in August) was used as an additional method
Lowland vole populations had regular density fluctuations with peaks in 1978-79. 1982-84 and 1987-88 Highland vole populations fluctuated less regularly and at lower over-all densities Highland lemming populations had two outbreaks, in 1978 and 1988, ending in abrupt winter crashes In the lowland, outbreak levels were reached only in 1978 All microtine declines in relatively productive lowland habitats were accompanied by intense activity of small mustelids. whereas avian predators were common only in 1983 Lowland declines also showed clear between-habitat asynchrony they started in areas with an exceptional abundance of productive habitats and then spread to more barren areas These lowland data are consistent with the hypothesis of a mustelid-microtine limit cycle, although also several other hypotheses remain unrefuted The highland lemming data suggest a simple exploiter-victim interaction between lemmings and the vegetation     

Habitat use of small mustelids in north Fennoscandian tundra: a test of the hypothesis of patchy exploitation ecosystems

The habitat use of small mustelids in a tundra area in Norwegian Lapland was studied chiefly by means of snow-tracking 1986-89 Stoats showed strong peference to a habitat complex immediately beneath the thrust line of the Scandes, with exceptional abundance of luxuriant habitats, whereas weasel activity was more evenly spread over the lowland tundra Mustelid activity on the high tundra above the thrust line was consistently low Within each subarea. stoat activity was concentrated to the most luxuriant habitats Similar preferences were shown by weasels on the lowland but not in the vicinity of the thurst cliff Daily movements of both species varied from local (c 200 m) to extensive (up to 4 km), no consistent interspecific differences in travel distances could be observed
The results largely conform to the hypothesis of patchy exploitation ecosystems (T Oksanen 1990a), according to which predator activity tends to "spill over' from luxuriant habitats, capable of supporting predator populations, to adjacent barren ones, due to despotic behavior within and between species and due to opportunistic predation by transient predators However, predator activity in barren habitats during the crash winter could not be explained by these mechanisms alone A third mechanism - breakdown of habitat preferences of predators during crash phases of a cyclic prey population - was thus introduced     

Review of the pharmacological properties of toremifene

New compounds were synthesized with the aim to develop new anti-estrogenic antitumor drugs. The biological properties of the molecules were screened by (1) estrogen receptor (ER) binding, (2) effect on MCF-7 cells, (3) uterotrophic effect and inhibition of estradiol induced uterotropic effect and (4) antitumor effect in DMBA induced rat mammary cancer. One of the molecules, Fc-1157a = toremifene, exhibited the following characteristics: competitive inhibition of [3H]estradiol binding to ER (IC50 = 0.3 mumol/l), inhibition of MCF-7 cell growth in a concentration-dependent manner and cell-killing effect at higher than 3 mumol/l concentrations. Minimal estrogenic dose of toremifene on rat uterus weight was about 40 times higher than that of tamoxifen. Toremifene had statistically significant effect against DMBA-induced rat mammary cancer. Further screening consisted of antitumor, pharmacokinetic and safety studies. Toremifene inhibited the growth of ER-negative, glucocorticoid sensitive, mouse uterine sarcoma in a dose-dependent manner. Pharmacokinetics and metabolism of toremifene resembled closely those of tamoxifen, but since the chlorine atom of the toremifene molecule was not metabolically cleaved tamoxifen and toremifene did not have chemically similar metabolites. Toremifene was well tolerated in animal toxicity studies. No hyperplastic or neoplastic nodules, which were seen in almost all high-dose (48 mg/kg for 24 weeks) tamoxifen-treated rats, were found in toremifene-treated rats (dose 48 mg/kg). In clinical phase I studies in healthy voluntary postmenopausal women, no side effects were reported, at doses less than or equal to 460 mg, neither after a single dose nor after five daily doses. At the dose of 680 mg two out of five persons experienced vertigo and headache. Toremifene, at the dose of 68 mg daily, had antiestrogenic effect on estradiol-induced human vaginal epithelial cells. Clinical phase II studies have confirmed that toremifene has a promising antitumor effect.     

Metabolism of toremifene in the rat

Toremifene was labelled to a specific activity of about 20 microCi/mmol with tritium at positions 3 and 5 in the para-substituted phenyl ring. At these positions tritium is not eliminated within the metabolic pathways. A mixture of unlabelled and labelled toremifene (5 or 10 mg/kg, 5 microCi/mg) was given i.v. or p.o. to Sprague-Dawley rats. The elimination of radioactivity was followed up by collecting urine and feces daily for 13 days. The elimination of toremifene which was similar after p.o. and i.v. administration took place mainly in the feces. About 70% of the total radioactivity was eliminated within 13 days, of this amount more than 90% in the feces. All applied radioactivity could be detected in three separate fractions according to the oxidative state of the side chain when counted by Berthold TLC Linear Analyzer. Each fraction was further separated into single metabolites by TLC or HPLC. Altogether 9 metabolites were identified and almost all methanol-extractable components were identified. The main metabolic pathways in the rat were 4-hydroxylation and N-demethylation. The side chain was further oxidized to alcohols and carboxylic acids. Small amounts of unchanged toremifene were found in the feces both after p.o. and i.v. administration indicating biliary secretion.     

Mismatch Repair Genes on Chromosomes 2p and 3p Account for a Major Share of Hereditary Nonpolyposis Colorectal Cancer Families Evaluable by Linkage

Two susceptibility loci for hereditary nonpolyposis colo-rectal cancer (HNPCC) have been identified, and each contains a mismatch repair gene: MSH2 on chromosome 2p and MLH1 on chromosome 3p. We studied the involvement of these loci in 13 large HNPCC kindreds originating from three different continents. Six families showed close linkage to the 2p locus, and a heritable mutation of the MSH2 gene was subsequently found in four. The 2p-linked kindreds included a family characterized by the lack of extracolonic manifestations (Lynch I syndrome), as well as two families with cutaneous manifestations typical of the Muir-Torre syndrome. Four families showed evidence for linkage to the 3p locus, and a heritable mutation of the MLH1 gene was later detected in three. One 3p-linked kindred was of Amerindian origin. Of the remaining three families studied for linkage, one showed lod scores compatible with exclusion of both MSH2 and MLH1, while lod scores obtained in the other two families suggested exclusion of one HNPCC locus (MSH2 or MLH1) but were uninformative for markers flanking the other locus. Our results suggest that mismatch repair genes on 2p and 3p account for a major share of HNPCC in kindreds that can be evaluated by linkage analysis.     

Egg presence, egg loss, and female mate preferences in the sand goby (Pomatoschistus minutus)

We studied the effect of egg presence on female mate choicein a fish with paternal care. Females who were allowed a freechoice between two males mated within a shorter time than femaleswho were randomly assigned to a particular male. When a secondfemale was allowed to choose among the males, she preferredthe same male as the previous female. This result shows thatfemales are concordant in their mate choice. When the initialfemale was randomly assigned to mate with one of two males (forcedchoice), the second female mated randomly with respect to thefirst one. Thus females do not prefer males with eggs. If theinitial female was given a free choice, but the eggs were removedfrom the chosen male, the test female mated randomly. When boththe males initially had mated but one randomly determined male'seggs were removed, the test female preferred the male who wasstill guarding eggs. These experiments show that females avoidspawning in unsuccessful nests. When the females in the freechoice/egg removal experiment mated with the unsuccessful malethere was a considerably bigger size difference in favor ofthis male than when the females mated with the other male. Weconclude that female sand gobies show clear mate preferences,but that they do not prefer males with eggs over males withouteggs. They do, however, avoid mating with males guarding unsuccessfulnests. We therefore suggest that egg loss could be an importantfactor selecting for egg preference.     

Light and electron microscopy of the ducts and their subepithelial tissue in the rat ventral prostate

Summary The ducts of the rat ventral prostate have been studied by light and electron microscopy for elucidation of their role in prostatic function. The epithelium of the main duct consists of simple columnar cells and polymorphic basal cells. The columnar cells show no indication of secretory activity. The basal cells contain bundles of filaments of 5–6 nm thickness and numerous pinocytotic vesicles. The ducts are surrounded by layers of circular smooth muscle cells interspersed with nerve axons. On ultrastructural grounds the ducts do not appear to secrete material into the seminal fluid, but apparently the muscular coat actively helps drain the gland during ejaculation.