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Rosiglitazone and ethinyl estradiol/cyproterone acetate as single and combined treatment of overweight women with polycystic ovary syndrome and insulin resistance.

BACKGROUND: Few studies have evaluated insulin sensitizers in comparison/association with oral contraceptives (OC) in women with polycystic ovary syndrome (PCOS) with insulin resistance (IR). This study assessed the effects of a thiazolidinedione versus an anti-androgenic estrogen-progestin followed by their sequential combinations in overweight PCOS women. METHODS AND RESULTS: Twenty-eight candidates in whom elevated insulin was not normalized after 4 months of diet were randomly assigned to 6 months of rosiglitazone 4 mg/day or to ethinyl estradiol 35 mg/cyproterone acetate 2 mg (EE/CPA: 21/28 days cycle). Each group then received both medications for another 6 months. Rosiglitazone reduced insulin, IR indices [homeostasis model assessment (HOMA) and quantitative sensitivity check index (QUICKI)] and the insulin area under the curve in response to an oral glucose tolerance test (OGTT), but had limited effect on lipids, androgens and hirsutism. EE/CPA did not modify insulin and OGTT response but increased high-density lipoprotein cholesterol and triglycerides and decreased androgens and hirsutism. Similar changes occurred during combined treatments. End results were highly significant in combined groups without noticeable side-effects or changes in safety parameters. CONCLUSIONS: In obese PCOS women with high insulin not corrected by diet, the combination of rosiglitazone and EE/CPA may be used to achieve complementary beneficial effects on endocrine-metabolic anomalies and clinical symptoms.

Adolescent↗

Cryoanalgesia for post-thoracotomy pain.

Intercostal block by a freezing technique was compared with blockade by local anaesthetics or no blockade as a method of treating post-thoracotomy pain. The 15 patients who received cryotherapy had significantly less postoperative pain than the 9 patients whose nerves were blocked by local anaesthetics or who did not receive any nerve block. The interruption of nerve function produced by cryotherapy was temporary (not more than 30 days), and there were no adverse sequelae.

Analgesia↗

Diversity of endophytic fungi of single Norway spruce needles and their role as pioneer decomposers.

The diversity of endophytic fungi within single symptomless Norway spruce needles is described and their possible role as pioneer decomposers after needle detachment is investigated. The majority (90%) of all 182 isolates from green intact needles were identified as Lophodermium piceae. Up to 34 isolates were obtained from single needles. Generally, all isolates within single needles had distinct randomly amplified microsatellite (RAMS) patterns. Single trees may thus contain a higher number of L. piceae individuals than the number of their needles. To investigate the ability of needle endophytes to act as pioneer decomposers, surface-sterilized needles were incubated on sterile sand inoculated with autoclaved or live spruce forest humus layer. The dry weight loss of 13-17% found in needles after a 20-week incubation did not significantly differ between the sterilized and live treatments. Hence, fungi surviving the surface sterilization of needles can act as pioneer decomposers. A considerable portion of the needles remained green during the incubation. Brown and black needles, in which the weight loss had presumably taken place, were invaded throughout by single haplotypes different from L. piceae. Instead, Tiarasporella parca, a less common needle endophyte, occurred among these invaders of brown needles. Needle endophytes of Norway spruce seem thus to have different abilities to decompose host tissues after needle cast. L. piceae is obviously not an important pioneer decomposer of Norway spruce needles. The diversity of fungal individuals drops sharply when needles start to decompose. Thus, in single needles the decomposing mycota is considerably less diverse than the endophytic mycota.

Ascomycota↗

Nitrogen spatial heterogeneity influences diversity following restoration in a ponderosa pine forest, Montana.

The resource heterogeneity hypothesis (RHH) is frequently cited in the ecological literature as an important mechanism for maintaining species diversity. The RHH has rarely been evaluated in the context of restoration ecology in which a commonly cited goal is to restore diversity. In this study we focused on the spatial heterogeneity of total inorganic nitrogen (TIN) following restoration treatments in a ponderosa pine (Pinus ponderosa)/Douglas-fir (Pseudotsuga menziesii) forest in western Montana, USA. Our objective was to evaluate relationships between understory species richness and TIN heterogeneity following mechanical thinning (thin-only), prescribed burning (burn-only), and mechanical thinning with prescribed burning (thin/burn) to discern the ecological and management implications of these restoration approaches. We employed a randomized block design, with three 9-ha replicates of each treatment and an untreated control. Within each treatment, we randomly established a 20 x 50 m (1000 m2) plot in which we measured species richness across the entire plot and in 12 1-m(2) quadrats randomly placed within each larger plot. Additionally, we measured TIN from a grid consisting of 112 soil samples (0-5 cm) in each plot and computed standard deviations as a measure of heterogeneity. We found a correlation between the net increase in species richness and the TIN standard deviations one and two years following restoration treatments, supporting RHH. Using nonmetric multidimensional scaling ordination and chi-squared analysis, we found that high and low TIN quadrats contained different understory communities in 2003 and 2004, further supporting RHH. A comparison of restoration treatments demonstrated that thin/burn and burn-only treatments created higher N heterogeneity relative to the control. We also found that within prescribed burn treatments, TIN heterogeneity was positively correlated with fine-fuel consumption, a variable reflecting burn severity. These findings may lead to more informed restoration decisions that consider treatment effects on understory diversity in ponderosa pine/Douglas-fir ecosystems.

Biodiversity↗

Assessment of auditory distance in a territorial songbird: accurate feat or rule of thumb?

Territorial passerines presumably benefit from their ability to use auditory cues to judge the distance to singing conspecifics, by increasing the efficiency of their territorial defence. Here, we report data on the approach of male territorial chaffinches, Fringilla coelebs, to a loudspeaker broadcasting conspecific song simulating a rival at various distances by different amounts of song degradation. Songs were degraded digitally in a computer-simulated forest emulating distances of 0, 20, 40, 80 and 120 m. The approach distance of chaffinches towards the loudspeaker increased with increasing amounts of degradation indicating a perceptual representation of differences in distance of a sound source. We discuss the interindividual variation of male responses with respect to constraints resulting from random variation of ranging cues provided by the environmental song degradation, the perception accuracy and the decision rules. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗

Population structure and coil dimorphism in a tropical land snail.

Tree snails of the subgenus Amphidromus s. str. are unusual because of the chiral dimorphism that exists in many species, with clockwise (dextrally) and counter-clockwise (sinistrally) coiled individuals co-occurring in the same population. Given that mating in snails is normally impeded when the two partners have opposite coil, positive frequency-dependent selection should prevent such dimorphism from persisting. We test the hypothesis that a strong population structure with little movement between tree-based demes may result in the fixation of coiling morphs at a very small spatial scale, but apparent dimorphism at all larger scales. To do so, we describe the spatial structure in a Malaysian population of A. inversus (Müller, 1774) with 36% dextrals. We marked almost 700 juvenile and adult snails in a piece of forest consisting of 92 separate trees, and recorded dispersal and the proportions of dextrals and sinistrals in all trees over a 7-day period. We observed frequent movement between trees (155 events), and found that no trees had snail populations with proportions of dextrals and sinistrals that were significantly different from random. Upon recapture 1 year later, almost two-thirds of the snails had moved away from their original tree. We conclude that population structure alone cannot stabilise the coil dimorphism in Amphidromus.

Animal Structures↗

Undescended testis: comparison of two protocols of treatment with human chorionic gonadotropin. Effect on testicular descent and hormonal response.

A randomized study of two protocols of human chorionic gonadotropin (hCG) treatment was performed in 183 prepubertal boys between 7 months and 12 years of age: protocol I, in which the boys were given 7 injections of 1,500 IU every other day, and protocol II consisting of 4 injections of 100 IU/kg at 4- to 5-day intervals. In both protocols, by the end of the test, testosterone had risen significantly to values within the normal adult male range. However, the amplitude of the rise was slightly but significantly lower using protocol II (4.08 +/- 2.07 ng/ml) than protocol I (5.16 +/- 2.73 ng/ml). It would thus appear that repetition of the hCG injection at intervals of less than 4 days is unnecessary, and that a total stimulation period of 2-3 weeks is sufficient. Although not correlated with testosterone levels, the success rates for treatment were similar in both protocols and comparable to rates reported in the literature.

Adolescent↗

High genetic diversity in a population of the ectomycorrhizal basidiomycete laccaria amethystina in a 150-year-old beech forest

The genetic structure of a population of the ectomycorrhizal basidiomycete Laccaria amethystina (Bolt. ex Hooker) Murr. was assessed in a closed 150-year-old beech (Fagus sylvatica L.) forest in the Vosges Mountains in northeastern France. During the autumn of 1994 and 1997, sporophores were collected from three 100-m2 sampling plots located along a 120-m transect crossing the beech stand. The genetic variation of 676 sporophores was initially estimated using heteroduplex analysis of the ribosomal DNA intergenic spacer (IGS1). Ten unique IGS1 heteroduplex/homoduplex patterns were identified, although three types represented most of the sporophores analysed. Each group of IGS1 type was then analysed using random amplified microsatellite analysis (RAMS). RAMS resolved 388 different genotypes amongst the 634 sporophores analysed from the three plots during the autumn of 1994 and 1997. Density as high as 130 genets per 100 m2 was observed during the autumn of 1994. The largest clone covered approximately 1 m2, but most genets covered a few cm2 and produced only one to three sporophores. Only eight genotypes identified in 1994 were found in 1997. Although L. amethystina has the capacity for vegetative persistence, the present study indicates that its populations maintain a genetic structure more consistent with a high frequency of sexual reproduction. This suggests that beech trees could be recolonized by new genotypes each year. Alternatively, this spatial distribution may also arise from erratic fruiting of underground persistent genets. These features (i.e. numerous genets of small size), typical of ruderal species, contrast with studies carried out on other ectomycorrhizal basidiomycetes occurring in mature closed forests.

Journal Article↗

Molecular diversity of arbuscular mycorrhizal fungi and patterns of host association over time and space in a tropical forest.

We have used molecular techniques to investigate the diversity and distribution of the arbuscular mycorrhizal (AM) fungi colonizing tree seedling roots in the tropical forest on Barro Colorado Island (BCI), Republic of Panama. In the first year, we sampled newly emergent seedlings of the understory treelet Faramea occidentalis and the canopy emergent Tetragastris panamensis, from mixed seedling carpets at each of two sites. The following year we sampled surviving seedlings from these cohorts. The roots of 48 plants were analysed using AM fungal-specific primers to amplify and clone partial small subunit (SSU) ribosomal RNA gene sequences. Over 1300 clones were screened for random fragment length polymorphism (RFLP) variation and 7% of these were sequenced. Compared with AM fungal communities sampled from temperate habitats using the same method, the overall diversity was high, with a total of 30 AM fungal types identified. Seventeen of these types have not been recorded previously, with the remainder being similar to types reported from temperate habitats. The tropical mycorrhizal population showed significant spatial heterogeneity and nonrandom associations with the different hosts. Moreover there was a strong shift in the mycorrhizal communities over time. AM fungal types that were dominant in the newly germinated seedlings were almost entirely replaced by previously rare types in the surviving seedlings the following year. The high diversity and huge variation detected across time points, sites and hosts, implies that the AM fungal types are ecologically distinct and thus may have the potential to influence recruitment and host composition in tropical forests.

Base Sequence↗

Testing the relative conspicuity of safety garments for New Zealand forestry workers.

The relative conspicuities of six test garments (fluorescent orange, green/red, high-contrast, fluorescent lime-yellow, white, black) were assessed to guide the selection process of a standard upper body safety garment to be used within the New Zealand logging industry. Six male and four female participants, aged between 18 and 26 years, volunteered to perform 10 trials each on a demanding, central (tracking) task, while peripherally searching colour slides for test garments displayed on each of eight positions, against a pine forest background typically found in the New Zealand forestry. During each trial, transparency luminance was first gradually increased from darkness to daylight and then decreased to darkness again within 180 s. A head mounted ASL eye tracking system (4000SU) recorded the eye line of gaze for each participant, enabling a rank order of detection to be obtained for the tested garments in each trial. The fluorescent lime-yellow, fluorescent orange and white test garments were detected earlier than any other test garments across all trials, and the fluorescent lime-yellow test garment was detected first with a higher frequency than the white test garment. It was concluded that while white may be the most visible colour in near darkness conditions, as it provides highest contrast, fluorescent lime-yellow stands out better in twilight and daylight conditions against the pine forest background. The results of this study led to the promotion of fluorescent lime-yellow as the standard safety colour used in upper body garments within the New Zealand forest industry.

Adult↗

Genetic differentiation in Eurasian populations of the postfire ascomycete Daldinia loculata.

The genetic population structure of the postfire ascomycete Daldinia loculata was studied to test for differentiation on a continental scale. Ninety-six samples of spore families, each comprising mycelia from six to 10 spores originating from single perithecia, were sampled from one Russian and six Fennoscandian forest sites. Allelic distribution was assayed for six nuclear gene loci by restriction enzyme analyses of polymerase chain reaction (PCR)-amplified gene fragments. In addition, the full sequence of the gene fragment was analysed for a subset of haploid single-ascospore isolates in a multiallelic approach. A third data set was generated by using arbitrary-primed PCR with the core sequence of the phage M13 as primer. Although there was a reduction in heterozygosity in the total population from what would have been expected at random mating, the levels of genetic differentiation among the Eurasian subpopulations of D. loculata were low. All subpopulations were found to be in Hardy-Weinberg equilibrium and gametic equilibrium was observed between all investigated nuclear gene loci. The results obtained by the different markers were consistent; we confirmed low levels of genetic differentiation among the Eurasian subpopulations of D. loculata. The differentiation did not increase with distance; the Russian subpopulation, sampled more than 7000 km from the Fennoscandian subpopulations, was only moderately differentiated from the others (FST = 0.00-0.14). In contrast, one of the Swedish populations was the most highly differentiated from the others, with FST and GST values of 0.10-0.16. The results suggest that D. loculata consists of a long-lived background Eurasian population of latent mycelia in nonburned forests, established by sexual ascospores dispersed from scattered burned forest sites. Local differentiation is probably due to founder effects of populations in areas with low fire frequency. A tentative life cycle of D. loculata is presented.

Ascomycota↗

Fine-scale clonal structure and diversity within patches of a clone-forming dioecious shrub, Ilex leucoclada (Aquifoliaceae).

BACKGROUND AND AIMS: The mode of reproduction (sexual vs. asexual) is likely to have important effects on genetic variation and its spatial distribution within plant populations. An investigation was undertaken of fine-scale clonal structure and diversity within patches of Ilex leucoclada (a clone-forming dioecious shrub). METHODS: Six patches were selected in a 1-ha plot previously established in an old-growth beech forest. Two of the selected patches were composed predominantly of stems with male flowers (male patch), and two contained stems with predominantly female flowers (female patch). The remaining two patches contained stems with male flowers and stems with female flowers in more or less equal proportions (mixed patch). Different genets were distinguished using random amplified polymorphic DNA (RAPD) markers. KEY RESULTS: One hundred and fifty-six genets with different RAPD phenotypes were identified among 1928 stems from the six patches. Among the six patches, the male patches had the lowest clonal diversity, and the mixed patches had the highest. Distribution maps of the genets showed that they extended downhill, reflecting natural layering that occurred when stems were pressed to the ground by heavy snow. In every patch, there were a few large genets with many stems and many small genets with a few stems. CONCLUSION: The differences in clonal diversity among patches may be due to differences in seedling recruitment frequencies. The skewed distribution of genet size (defined as the number of stems per genet) within patches may be due to differences in the timing of germination, or age (with early-establishing genets having clear advantages for acquiring resources) and/or intraspecific competition.

Demography↗

Virus meningo-encephalitis in Slovenia. 4. Isolation of the virus from the ticks Ixodes ricinus.

This article describes the steps taken to verify that the tick Ixodes ricinus is the main vector of Slovenian meningo-encephalitis.In 1954, several unsuccessful attempts were made to isolate the virus from unengorged ticks collected at random, but in the following year this system was abandoned, and instead the search for specimens was carried out on the basis of evidence supplied by meningo-encephalitis patients with a tick-bite case history.In June-the peak endemic period-140 unengorged ticks were collected from a part of a forest in central Slovenia where one of these patients had been working. The ticks were washed in alcohol, finely ground, and centrifuged, and the supernatant was inoculated intracerebrally into suckling mice, and intraperitoneally into adult mice and guinea-pigs. The infected suckling mice died between the fourteenth and eighteenth day after inoculation; a suspension of their brains was inoculated intracerebrally into a further batch of suckling and adult mice, which subsequently fell ill, showing signs in the central nervous system.The virus strain obtained was subjected to neutralization and complement-fixation tests, in order to identify the infective agent.

Adult↗

Decomposition rate of organic substrates in relation to the species diversity of soil saprophytic fungi.

Despite the great interest concerning the relationship between species diversity and ecosystem functioning, there is virtually no knowledge as to how the diversity of decomposer microbes influences the decomposition rate of soil organic matter. We established a microcosm study in which the number of soil fungi was investigated in relation to the system's ability to (i) degrade raw coniferous forest humus, and (ii) use resources that were either added to the systems or released into the soils after a disturbance (drought). With the exception of the most diverse treatment, in each of the six replicates of each of the six diversity treatments (1, 3, 6, 12, 24 or 43 taxa), fungal taxa were randomly chosen from a pool of 43 commonly isolated fungal species of raw humus. Two months after initiation of the study CO2 production increased as fungal diversity increased, but in the species-poor end of the diversity gradient only. Addition of various energy resources to the microcosms generally increased the level of soil respiration but did not affect the shape of the diversity-CO2-production curve. Rewetting the soil after severe drought resulted in a rapid flush of CO2, particularly in the most diverse communities. The biomass of the fungi in the non-disturbed soils, and soil NH4-N concentration and soil pH in both disturbed and non-disturbed systems were slightly but significantly higher in the diverse than in the simple systems. Fungal species richness had no influence on the organic matter content of the humus at the end of the experiment. The results suggest that the functional efficiency of fungal communities can increase with the number of fungal taxa. This diversity effect was, however, significant at the species-poor end of the diversity gradient only, which implies considerable functional equivalency (redundancy) among the decomposer fungi.

Carbon Dioxide↗

ROLL: a method of preparation of gene-specific oligonucleotide libraries.

The selection of nucleic acid sequences capable of specifically and efficiently hybridizing to target sequences is crucial to the success of many applications, including microarrays, PCR and other amplification procedures, antisense inhibition, ribozyme-mediated cleavage, and RNA interference (RNAi). Methods of selection using nucleotide sequence libraries have several advantages over rational approaches using defined sequences. However, the high complexity of completely random (degenerate) libraries and their high toxicity in cell-based assays make their use in many applications impractical. Gene-specific oligonucleotide libraries, which contain all possible sequences of a certain length occurring within a given gene, have much lower complexity and, thus, can significantly simplify and accelerate sequence screening. Here, we describe a new method for the preparation of gene-specific libraries using the ligation of randomized oligonucleotide probes hybridized adjacently on target polynucleotide templates followed by PCR amplification. We call this method random oligonucleotide ligated libraries (ROLL).

Base Sequence↗

Low-dose adjuvant interferon for stage III malignant melanoma.

The role of interferon as adjuvant therapy in stage III melanoma has recently been questioned. Prospective randomized studies have shown conflicting results regarding the efficacy of adjuvant treatment. The purpose of this study was to examine the use of low-dose adjuvant interferon alpha2-b (IFN) in stage III melanoma patients treated at a single institution. This study was a retrospective analysis of 60 stage III melanoma cases from Wake Forest University treated between 1983 and 1998. Cases were identified via the tumor registry. All patients underwent standard lymphadenectomy after diagnosis. After recovery from surgery patients were offered low-dose IFN (3 million units subcutaneous TIW for 1 month and then 6 million units subcutaneous TIW for 11 months) as adjuvant therapy for stage III melanoma. The patients were followed up jointly by medical and surgical oncology. There were 39 male and 21 female patients with mean age of 60.0 (range 37-89) years. The average number of positive nodes was 3.6 (median = 1) for the treated group and 1.8 (median = 1) for those untreated (P = 0.71). The average tumor thickness was similar between groups: 4.71 versus 4.88 mm for the IFN and observation groups respectively. The IFN group (N = 25) that received low-dose treatment had a median survival of 7.9 years with a 5-year survival rate of 69 per cent. The 35 cases that did not receive interferon had a median survival of 6.5 years and a 5-year survival rate of 52 per cent. These survival rates were not significantly different (P = 0.91). The median disease-free survival for patients who did not receive IFN treatment was 2.4 years and 1.4 years for the treated group (P = 0.19). The data show that there was similar survival for those who did and did not receive the low-dose IFN treatment. Although only large prospective trials can conclusively exclude a small survival time this experience suggests that there is no significant survival advantage to low-dose adjuvant IFN therapy for stage III melanoma patients. Hopefully upcoming cooperative group trials will clarify the potential value of adjuvant IFN in this setting. However, although the toxicity of this regimen was mild we suggest that low-dose adjuvant IFN for stage III melanoma should not be utilized outside the setting of a clinical trial.

Adjuvants, Immunologic↗

Flaxseed dietary supplement versus hormone replacement therapy in hypercholesterolemic menopausal women.

OBJECTIVE: To assess serum lipid changes by a phytoestrogen dietary supplement compared with oral estrogen-progesterone replacement in hypercholesterolemic menopausal women. METHODS: Twenty-five menopausal patients with total cholesterol greater than 6.2 mmol/L (240 mg/dL), a cholesterol/high-density lipoprotein-cholesterol ratio greater than 4.5 and triglycerides less than 3.5 mmol/L (310 mg/dL) after a 4-month diet, were randomized to add 40 g/day of crushed flaxseed to their diet or to take daily 0.625 mg of conjugated equine estrogens alone (hysterectomy, n = 10) or combined with 100 mg of micronized progesterone (intact uterus, n = 15). After 2 months of treatment, both groups continued the diet alone during a 2-month washout period before crossing over to the alternate treatment for 2 more months. RESULTS: Differences were found between hormone replacement therapy and flaxseed respectively for decrease of low-density lipoprotein cholesterol (3.8 +/- 0.2 versus 4.4 +/- 0.2 mmol/L) (148 +/- 8 versus 170 +/- 8 mg/dL) (P =.10), increase of high-density lipoprotein cholesterol (1.6 +/- 0.04 versus 1.3 +/- 0.03 mmol/L) (62 +/- 1 versus 50 +/- 1 mg/dL) (P =.001), and increase of apolipoprotein A-1 (1.71 +/- 0.07 versus 1.42 +/- 0.05 g/L) (P =.003). These changes were not related to modifications in diet, exercise, or anthropometric measurements evaluated in parallel. Both treatments produced similar decreases in menopausal symptoms and in glucose and insulin levels. Only hormone replacement therapy as compared with flaxseed induced an elevation of sex hormone binding globulin (P =.004), lowered fibrinogen (P =.08), and plasminogen activator inhibitor type 1 (P =.01). CONCLUSION: Although 40 g of flaxseed is as effective as oral estrogen-progesterone to improve mild menopausal symptoms and to lower glucose and insulin levels, only hormone replacement therapy significantly improves cholesterol profile in hypercholesterolemic women and favorably modifies markers related to cardiovascular health.

Cholesterol, HDL↗

[Population dynamics of Quercus variabilis on northern slope of Qinling mountains].

Studies on the population dynamics, age structure, spatial distribution pattern, life table, and survival curve of Quercus variabilis showed that the Q. variabilis population on the northern slope of Qinling mountains was increasing. The number of young-aged individuals was larger, and that of middle-aged and old individuals was smaller. The life tables for different age classes showed that the mortality at age classes I and II was the highest, and the mortality rate was decreased with increasing age. However, at age classes VII and VIII, the mortality rose again for their decrepitude. The expected life span of age classes III, IV and V was higher, and decreased gradually with increasing age. The survival curves were the type of Deevey III, and the distribution pattern of population was aggregative as a whole. As the age increased, the intensity of aggregation decreased, and tended to a random distribution at higher elevations. A wise management should accelerate the recovery of Q. variabilis population and the enhancement of its productivity. The altitude 800-1,100 m was the favorable habitat for Q. variabilis population. As for the Q. variabilis at lower altitude, its protection should be reinforced, and the disturbance from human beings should be reduced. Forest thinning and other fostering management at middle altitude should be given in time. The target trees at higher altitude should be fostered.

Altitude↗