Aluminum in lake water and organs of a fish Tribolodon hakonensis in strongly acidic lakes with a high aluminum concentration

Aluminum in lake water and in the organs of the fish Tribolodon hakonensis was investigated in Lake Usoriko (pH 3.6), Lake Inawashiroko (pH 5.0), and the Tenryu River (pH 7.7). The concentration of total soluble aluminum in the water was 0.51 mg l⁻¹ in Usoriko, 0.05 mg l⁻¹ in Inawashiroko, and less than 0.01 mg l⁻¹ in the Tenryu. The chemical forms of soluble aluminum in the acid water were characterized as Al³⁺, AlL²⁺, and AlL^≦1+. More than 90% of soluble aluminum in the water of Usoriko was Al³⁺, whereas AlL²⁺ was dominant in the water of Inawashiroko. The aluminum concentration in the organs of T. hakonensis in Usoriko was 42 μg g⁻¹ wet weight in gills, 4.2 μg g⁻¹ in muscle, 6.9 μg g⁻¹ in bone, 12.7 μg g⁻¹ in liver, 6.0 μg g⁻¹ in kidney, and 6.0 μg g⁻¹ in intestine, indicating accumulation of aluminum in the gills. The aluminum concentration in the organs of T. hakonensis living in Inawashiroko was approximately the same, in spite of the difference in water chemistry of the two acid lakes, especially for pH and aluminum. This suggests that aluminum accumulation might be controlled in the fish living in the acid lakes. In contrast, the aluminum concentration in the gills of T. hakonensis from the Tenryu was 2 μg g⁻¹. Received: May 20, 1999 / Accepted: December 10, 1999     

Expression and function of the bHLH genes ALCATRAZ and SPATULA in selected Solanaceae species

The genetic mechanisms underlying fruit development have been identified in Arabidopsis and have been comparatively studied in tomato as a representative of fleshy fruits. However, comparative expression and functional analyses on the bHLH genes downstream the genetic network, ALCATRAZ (ALC) and SPATULA (SPT), which are involved in the formation of the dehiscence zone in Arabidopsis, have not been functionally studied in the Solanaceae. Here, we perform detailed expression and functional studies of ALC/SPT homologs in Nicotiana obtusifolia with capsules, and in Capsicum annuum and Solanum lycopersicum with berries. In Solanaceae, ALC and SPT genes are expressed in leaves, and all floral organs, especially in petal margins, stamens and carpels; however, their expression changes during fruit maturation according to the fruit type. Functional analyses show that downregulation of ALC/SPT genes does not have an effect on gynoecium patterning; however, they have acquired opposite roles in petal expansion and have been co‐opted in leaf pigmentation in Solanaceae. In addition, ALC/SPT genes repress lignification in time and space during fruit development in Solanaceae. Altogether, some roles of ALC and SPT genes are different between Brassicaceae and Solanaceae; while the paralogs have undergone some subfunctionalization in the former they are mostly redundant in the latter.     

Effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification

Objective

The aim of this study was to detect the effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification.

Study design

The percentages of morphologically normal primordial follicles and the follicles expressing bax protein in ovarian tissues after vitrification–warming were measured. Besides, the 17-β estradiol levels in the culture supernatants were measured.

Results

The percentages of morphologically normal primordial follicles in vitrified–warmed ovarian tissues slicing in 0.5–1.5 mm in length and wide, and 1.0 mm in thickness were significantly higher than those slicing in 2.0 mm in length and wide, and 1.0 mm in thickness. Moreover, the follicles expressing bax protein in vitrified–warmed ovarian tissues slicing in 0.5–1.5 mm in length and wide, and 1.0 mm in thickness were significantly lower than those slicing in 2.0 mm in length and wide, and 1.0 mm in thickness. The 17-β estradiol levels in the culture supernatants slicing in 1.0–1.5 mm in length and wide, and 1.0 mm in thickness were significantly higher than those slicing in 0.5 mm or 2.0 mm in length and wide, and 1.0 mm in thickness.

Conclusions

Cortex piece slicing in 1.0–1.5 mm in length and wide, and 1.0 mm in thickness is suitable for baboon ovarian vitrification.     

Nitric oxide production and absorption in trachea, bronchi, bronchioles, and respiratory bronchioles of humans

Different volumesof dead-space gas were collected and analyzed for nitric oxide (NO)content, either immediately after inspiration or after a period ofbreath holding on clean air or NO mixtures. This allowed calculation ofNO equilibrium, NO production, and NO absorption. In seven young,healthy, adult nonsmokers, the mean NO equilibrium values in parts perbillion (ppb) were 56 ± 11 (SE) in the trachea, 37 ± 6 in thebronchi, 21 ± 3 in the bronchioles, and 16 ± 2 in therespiratory bronchioles. At any given NO concentration, the NOabsorption rate (in nl/min) equaled the NO concentration (in ppb) timesA (the absorption coefficient inl/min). A values (in l/min) were 0.11 ± 0.01 in the trachea, 0.17 ± 0.04 in the bronchi, 0.66 ± 0.09 in the bronchioles, and 1.35 ± 0.32 in the respiratorybronchioles. NO equilibrium concentrations and production rates in one74-yr-old subject were three to five times as high as those found inthe young subjects. Mouth equilibrium NO concentrations were 3 and 6 parts per million in two subjects who had oral production rates of 6 and 23 nl/min, respectively. In conclusion, production and absorptionof NO occur throughout the first 450 ml of the airways.

     

北京河流底栖硅藻沿城乡梯度带空间分布及其季节变化

研究了北京市区沿城乡梯度带河流底栖硅藻的空间分布及其季节变化特征。通过在2014年的春季、夏季和秋季在山区对照溪流、城市上游河道和城市下游河道3个样区,共23个样点进行了底栖硅藻样品采集。分析表明,主要优势种的空间差异明显。在对照溪流,主要优势种为极小曲丝藻(Achnanthidium minutissimum);在城市上游河道,主要优势种分别为短文假十字脆杆藻(Pseudostaurosira brevistriata)和连结十字脆杆藻腹面变种(Staurosira construens var.venter);在城市下游河道,主要优势种为谷皮菱形藻(Nitzschia palea)。然而,3个样区内的主要优势种相对丰度季节变化较小(P0.05)。其中,A.minutissimum及P.brevistriata的季节变化特征均为春季秋季夏季,而S.construens var.venter及N.palea的季节变化特征均为春季夏季秋季。结果发现,北京市城乡梯度带的河流硅藻种类组成差异较大,但主要优势属种季节变化相对较小,表明硅藻种类能较好地反映城乡梯度带的河流环境变化状况,可用于北京市河流水质生物监测。     

Biomass carbon density and carbon sequestration capacity in seven typical forest types of the Xiaoxing’an Mountains,China

森林生物碳储量作为森林生态系统碳库的重要组成部分,在全球碳循环中发挥着重要作用。以小兴安岭7种典型林型为研究对象,通过外业样地调查与室内实验分析相结合的方法,从林分尺度对林分生物量与碳密度进行计量,分析了林分生物碳储量的空间分配格局,并对林分年固碳能力与碳汇潜力进行了探讨。结果表明:小兴安岭不同林型从幼龄林到成熟林的乔木层碳密度增长速率为:蒙古栎(Quercus mongolica)林>兴安落叶松(Larix gmelinii)林>云冷杉(Picea-Abies)林>樟子松(Pinus sylvestris var.mongolica)林>山杨(Populus davidiana)林>红松(Pinus koraiensis)林>白桦(Betula platyphylla)林。7种典型林型不同龄组(幼龄林、中龄林、近熟林和成熟林)林分生物量碳密度分别为:红松林31.4、74.7、118.4和130.2 t·hm–2;兴安落叶松林28.9、44.3、74.2和113.3 t·hm–2;樟子松林22.8、52.0、71.1和92.6 t·hm–2;云冷杉林23.1、44.1、77.6和130.3 t·hm–2;白桦林18.8、35.3、66.6和88.5 t·hm–2;蒙古栎林25.0、20.0、47.5和68.9 t·hm–2;山杨林19.8、28.7、43.7和76.6 t·hm–2。红松林、兴安落叶松林、樟子松林和蒙古栎林在幼龄林时林分年固碳量较高,其他林型在成熟林时林分年固碳量较高。7种典型林型不同龄组的林分生物量碳密度均随林龄增长而增加,但不同林型的碳汇功能存在差异,同一林型不同林龄的生物量碳密度增幅差异也较大。林分年固碳量在0.4–2.8 t·hm–2之间,碳汇能力较强、碳汇潜力较大。尤其是小兴安岭目前林分质量较差,幼龄林和中龄林所占的比重较大,具有较大的碳汇潜力。研究结果可为森林经营管理及碳汇功能评价提供参考。     

Protective role of intraperitoneally administrated vitamin E and selenium on the levels of total lipid,total cholesterol,and fatty acid composition of muscle and liver tissues in rats

The aim of this work was to determine the protective effects of intraperitoneally administrated vitamin E and Se on total lipid, total cholesterol, and fatty acid composition of rat liver and muscle tissues. Total lipid content of muscle tissue in Se and combination groups decreased as compared to the control group. However, the level of total lipid in the liver tissues was seen to decrease only in the combination group (P < 0.05). While the amount of total cholesterol in liver tissue was lower (P < 0.05) in the vitamin E and combination groups, the amount of total cholesterol in muscle tissue decreased (P < 0.05) in the combination group. The amount of linoleic acid in muscle tissue slightly decreased (P < 0.05), whereas the eicosenoic and eicosatrienoic acid amounts significantly increased (P < 0.01, P < 0.001) in the vitamin E group as compared to the control group. The amounts of most fatty acid decreased (P < 0.05) in the combination group. The proportions of eicosenoic, eicosatrienoic, and total polyunsaturated fatty acid (PUFA) within the total fatty acid were higher (P < 0.05) in vitamin E group, whereas these fatty acids proportions were lower (P < 0.05) in the Se group. Although the proportions of palmitic, linolenic, and total saturated fatty acids were low (P < 0.05), oleic and total unsaturated fatty acid proportions were higher (P < 0.05) in the combination group than in the control group. The amount of palmitic acid and total saturated fatty acid in liver tissue decreased (P < 0.01 and P < 0.05, respectively) in the vitamin E and combination groups. However, the amount of linoleic acid only decreased (P < 0.05) in the combination group. The amount of PUFA was slightly higher (P < 0.05) in vitamin E. The proportions of stearic acid and linoleic acid decreased (P < 0.05) both in the Se and combination groups. However, the proportions of eicosatrienoic, ω 6, and PUFA were slightly higher (P < 0.05) in the vitamin E group, but total saturated fatty acid proportion significantly decreased (P < 0.01) in both the vitamin E and combination groups. In conclusion, the level of total lipid and cholesterol in muscle and liver tissues were reduced by administrating vitamin E and Se together. Additionally, the fatty acid synthesis in the muscle and liver tissues was decreased by this process. However, it was observed that the protective effect of intraperitoneally administrated vitamin E was higher than Se on fatty acid composition in muscle and liver tissues. J. Cell. Biochem. 64:233–241. © 1997 Wiley-Liss, Inc.     

A comparative study of the epidermis of the common carp and the three Indian major carp

A comparative study has been made of the mucogenic epidermis of the common carp, Cyprinus carpio var. communis, and the three Indian major carps, Catla catla, Labeo rohita and Cirrhina mrigala: on the basis of epidermis structural organization, these species are easily differentiated. The epithelial cells in the superficial layer, as in most fishes, show secretory activity, evidenced by positive histochemical reactions, which is high in C. carpio var. communis, moderate in C. catla and low in L. rohita and C. mrigala. The epithelial cells in the underlying two or three layers also give positive reactions, though their intensity is relatively weak. The mucous cells in C. carpio var. communis are distributed in large numbers arranged in several superimposed layers in the outer regions of the epidermis, whereas in C. catla they are fewer in number and are widely separated in the surface layers as well as in the deeper layers of the epidermis; in both species the mucous cells appear rounded, large, and open on the surface by wide pores. In contrast, in L. rohita and C. mrigala the mucous cells are smaller, restricted mainly to the superficial layer, close together in a single row, and open on the surface by narrow pores. The overall density of mucous cells in L. rohita and C. mrigala, as in C. catla, is much lower than in C. carpio var. communis. In the epidermis of C. carpio var. communis there are a large number of mucous cells, and the few club cells are restricted to the deeper layers. In contrast, in the epidermis of the three Indian major carp the overall density of the mucous cells is much lower and the club cells are very numerous. It is suggested that the high density of club cells compensates an overall low density of mucous cells as an adaptation for an effective defence mechanism. Increased mucus production in the epidermis of C. carpio var. communis, as evidenced by a large number of mucous cells in outer regions and high secretory activity of superficial layer epithelial cells, is associated with increased precipitation of mud held in suspension, needed as an adaptation to the species’peculiar bottom-scooping habits. The varied density of the taste buds in the epidermis of the four carp is associated with their feeding habits.     

Biogeochemical processes in intensive zero-effluent marine fish culture with recirculating aerobic and anaerobic biofilters

The biogeochemical processes that drive nutrient transformations and recycling in organic marine sediment-water environments were studied for 17 months in a zero-effluent intensive recirculating culture system. The system consisted of a 10 m³ gilthead seabream (Sparus aurata) tank coupled to aerobic and anaerobic water treatment elements. Nutrients and alkalinity were measured in the system to quantify the main biogeochemical processes. Fractions of the carbon fed in feed were found in fish (18.3%) and in sludge (11%); the missing carbon was respired by fish (45%) and by aerobic (8.4%) and anaerobic (7.7%) microorganisms. Fractions of the nitrogen fed in feed were found in fish (15.4%) and in sludge (14.3%); the missing nitrogen was eliminated by nitrification-denitrification. Most of the phosphorus and ash fed in feed and not found in fish accumulated within the sludge in the system. The rates of nitrification, denitrification and sulphate reduction increased with time, reaching 0.3 g N m^− 2 d^− 1, 53 g N m^− 2 d^− 1 and 145 g S m^− 2 d^− 1, respectively. Nitrification developed more rapidly than denitrification, leading at first to nitrate accumulation (to 20 mmol NO₃ l^− 1 by day 200) and a decrease in alkalinity. Once denitrification surpassed nitrification, nitrate concentrations decreased, eventually being reduced to < 0.3 mmol NO₃ l^− 1 by day 510, and alkalinity stabilized. Toxic hydrogen sulphide, generated within the anaerobic sludge, was oxidized by oxygen and nitrate as it diffused through the anaerobic-aerobic sediment-water interface. When nitrate levels in the water above the sludge dropped below 2 mmol l^− 1, sulphide was also oxidized in the fluidized bed reactor. Denitrification reduced nitrate in the water, respired (jointly with sulphate reduction) carbon in the sludge, oxidized the hydrogen sulphide, and contributed to stabilization of alkalinity and accumulation of polyphosphate in bacteria as a major sink of labile P.     

Seasonality affects the parasitism levels in two fish species in the eastern Amazon region

Fish parasite communities have strong interactions with the environment, the host fish, and the aquatic invertebrate communities. Thus, factors directly involving their different life cycles, such as different host populations and environments, as well as seasonal fluctuations in water levels can cause different responses. The main factors structuring parasite communities may be the hydrodynamic variations, together with seasonal variations in the availability of infectious stages of parasites in the environment. The purpose of this study was therefore to investigate the influence of the rainy and dry seasons on parasite infracommunities in fish species in the Amazon River System of Brazil. Between October 2009 and April 2011, specimens of Colossoma macropomum and Colossoma macropomum × Piaractus brachypomus hybrids (tambatinga) were examined for the presence of parasites. The parasite communities were similar in these two species that both showed aggregate dispersion, although the hybrid specimens were less parasitized. For both hosts, the Brillouin diversity, species richness, evenness and Berger‐Parker dominance indices were similar in the rainy season and dry season, except that the Berger‐Parker dominance index for the C. macropomum × P. brachypomus hybrid was higher during the dry season. Ichthyophthirius multifiliis was the dominant parasite, followed by Piscinoodinium pillulare, in both hosts. However, C. macropomum had a higher prevalence and abundance in the dry season, while in the C. macropomum × P. brachypomus hybrid, only the I. multifiliis prevalence increased. The abundance of monogenean species (Anacanthorus spathulatus, Linguadactyloides brinkmanni, Mymarothecium and Notozothecium janauachensis) was higher during the dry season in the gills of C. macropomum. Despite overdispersion of the lernaeid Perulernaea gamitanae, a seasonal pattern was seen only in the C. macropomum × P. brachypomus hybrid, with higher prevalence in the rainy season. The low prevalence and abundance of the ectoparasites Tetrahymena sp., Trichodina sp. and Braga patagonica, as well as of the endoparasites Procamallalus (Spirocamallanus) inopinatus and Neoechinorhynchus buttnerae, were not affected by seasonality. This information is applicable in farming practice for these economically important fish, as it indicates the best time for prophylactic management and treatment against parasites, in order to prevent economic losses in fish farms.     

冰雪灾害对江西九连山常绿阔叶林的影响

以江西九连山国家自然保护区常绿阔叶林为对象,研究林分不同层次优势种受灾程度,分析物种海拔、坡度对受灾程度的影响。结果表明:乔木上层和中层树木以断稍为主,乔木下层树木以断稍和腰折为主,小树和幼树以压弯为主。在平均受损指数MDI(Mean Damage Index)方面,乔木上层米槠MDI值最高,拟赤杨最低; 乔木中层鸭公树MDI值最高,浙江新木姜子最低; 乔木下层米槠MDI值最高,浙江新木姜子最低; 小树米槠MDI值最高,细枝柃最低; 幼树二列叶柃MDI值最高,狗骨柴最低。海拔对不同林分层次树木的部分受损指标有显著影响(P<0.05); 整体上,不同林分层次树木的受损指标在700～760 m海拔生境高于640～700 m海拔生境。不同坡度生境下树木的受损指标均无显著差异(P>0.05)。     

Effects of the halocline on water quality and phytoplankton composition in a shallow brackish lake (Lake Obuchi, Japan)

The relationships of the halocline to both water quality and phytoplankton composition in Lake Obuchi, a shallow brackish lake in northern Japan, were investigated from April 2001 to December 2004. The halocline in this lake became stronger in summer (July–September, mean maximum density gradient 4.3–5.8 ρ_tm⁻¹) but weaker in spring, fall, and winter (1.9–3.3 ρ_tm⁻¹). Although the difference in water quality between the upper and lower layers separated by the halocline was high in summer, nutrients (PO₄³⁻-P and NH₄⁺-N) were eluted from the bottom sediment as levels of dissolved oxygen decreased in the bottom layer because of the strong stratification caused by the halocline formed over the long term. Moreover, phytoplankton taxa composition also differed between the upper and lower layers in summer, but was similar in other seasons. The dominant phytoplankton taxa in the upper layer in summer were Skeletonema costatum and Cyclotella spp., whereas in the lower layer, Gymnodinium spp. (Dinophyceae) and Chlorophyceae, which prefer eutrophic and low dissolved oxygen conditions, dominated. This suggests that the halocline was related to differentiations in both water quality and ecosystem components between the upper and lower layers in the brackish lake water.     

The A locus that controls anthocyanin accumulation in pepper encodes a MYB transcription factor homologous to Anthocyanin2 of Petunia

Pepper plants containing the dominant A gene accumulate anthocyanin pigments in the foliage, flower and immature fruit. We previously mapped A to pepper chromosome 10 in the F₂ progeny of a cross between 5226 (purple-fruited) and PI 159234 (green-fruited) to a region that corresponds, in tomato, to the location of Petunia anthocyanin 2 (An2), a regulator of anthocyanin biosynthesis. This suggested that A encodes a homologue of Petunia An2. Using the sequences of An2 and a corresponding tomato expressed sequence tag, we isolated a pepper cDNA orthologous to An2 that cosegregated with A. We subsequently determined the expression of A by Northern analysis, using RNA extracted from fruits, flowers and leaves of 5226 and PI 159234. In 5226, expression was detected in all stages of fruit development and in both flower and leaf. In contrast, A was not expressed in the sampled tissues in PI 159234. Genomic sequence comparison of A between green- and purple-fruited genotypes revealed no differences in the coding region, indicating that the lack of expression of A in the green genotypes can be attributed to variation in the promoter region. By analyzing the expression of the structural genes in the anthocyanin biosynthetic pathway in 5226 and PI 159234, it was determined that, similar to Petunia, the early genes in the pathway are regulated independently of A, while expression of the late genes is A-dependent.Communicated by R. Hagemann     

Depressed Antioxidant Status in Pregnant Women on Iron Supplements: Pathologic and Clinical Correlates

Iron (Fe) remains a commonly prescribed supplement in pregnancy. Its possible pathologic potential is either uncommonly considered or ignored. We determined the antioxidant status in pregnant women with and without Fe supplements. Fifty-eight apparently healthy pregnant women on Fe supplements were selected for the study from the antenatal clinic of the University College Hospital, Ibadan, Nigeria. Fifty-five aged matched pregnant women who were not on Fe from various parishes of the Christ Apostolic Church, Ibadan (non-drug using Christian sect) were randomly selected as controls. Both groups were classified according to the trimesters of pregnancy. The gestational age in both pregnant women on Fe supplements and non-supplement pregnant women was similar. Fruit and vegetables consumption was higher in the supplement than in the non-supplement group (57.2% vs. 37.3%). Anthropometric indices, weight, height, and BMI, were also similar. But while the weight of the Fe supplement group decreased by nearly 3% in the third trimester, it increased by over 10% (p < 0.00) in the non-supplement group in the same period. Serum Fe level was significantly higher in the supplement than the non-supplement group (p < 0.001). In contrast, the levels of the antioxidants, ascorbic acid, copper (Cu), zinc (Zn), and bilirubin were all significantly decreased (p < 0.05, p < 0.001, p < 0.05, and p < 0.05, respectively). Uric acid level though also lower in the supplement group did not reach statistical significance (p > 0.05), while vitamin E was similar in both groups. There was relative stability of all antioxidants except uric acid, which declined from the first to the last trimester in the non-supplement group. The significantly higher Fe level in the second trimester was sustained in the third trimester though to a lesser degree (p < 0.05) and associated with significant decreases in the following antioxidant levels in the supplement group, ascorbic acid, bilirubin, Cu, and Zn (p < 0.02, p < 0.02, p < 0.02, and p < 0.001, respectively). Uric acid and vitamin E though lower in the supplement group were not significantly different. Remarkably, percentage changes between the first and third trimesters revealed that serum Fe increased by over 116% in the Fe supplement group, while it only increased by over 50% in the non-supplement group. This was associated with 23.50% decrease in ascorbate level (p < 0.003) in the supplement group, while it decreased by only 3.70% in the non-supplement group (p > 0.05). Again vitamin E decreased by 17.22% in the supplement group, while it decreased by only 7.30% in the non-supplement group during the period. Uric acid and bilirubin levels decreased by similar proportions during the period, while Zn decreased by 18.55% in the supplement group and by 14.86% in the non-supplement group. In contrast Cu increased by 7.20% in the supplement group, while it increased by only 2.96 in the non-supplement group. Additionally, all the antioxidants in the supplement group except vitamin E, viz, ascorbic acid, bilirubin, Cu, uric acid, and Zn, were significantly inversely correlated with serum Fe level (r − 0.299, p < 0.05, r − 0.278, p < 0.05, r − 0.383, p < 0.05, and r − 0.0369, p < 0.05). These data imply markedly depressed antioxidant status in the Fe supplement pregnant group with attendant oxidative stress (most probably pro-oxidant Fe-induced). This is associated with molecular and cellular damage as well as a number of pathologic and clinical correlates that underlie the exacerbation of morbidity and mortality in maternal and child populations, particularly in the developing countries. This appears to call for serious caution and prior evaluation of antioxidant and Fe status and during the use of Fe supplements in pregnancy for monitoring and prognostic purposes and to avert or ameliorate oxidative stress-induced pathologies in maternal and fetal systems.     

Hepatic Adaptation Compensates Inactivation of Intestinal Arginine Biosynthesis in Suckling Mice

Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass) gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass ^fl and Villin-Cre mice. Unexpectedly, Ass ^fl/fl /VilCre ^tg/- mice showed no developmental impairments. Amino-acid fluxes across the intestine, liver, and kidneys were calculated after determining the blood flow in the portal vein, and hepatic and renal arteries (86%, 14%, and 33%, respectively, of the transhepatic blood flow in 14-day-old mice). Relative to control mice, citrulline production in the splanchnic region of Ass ^fl/fl /VilCre ^tg/- mice doubled, while arginine production was abolished. Furthermore, the net production of arginine and most other amino acids in the liver of suckling control mice declined to naught or even changed to consumption in Ass ^fl/fl /VilCre ^tg/- mice, and had, thus, become remarkably similar to that of post-weaning wild-type mice, which no longer express arginine-biosynthesizing enzymes in their small intestine. The adaptive changes in liver function were accompanied by an increased expression of genes involved in arginine metabolism (Asl, Got1, Gpt2, Glud1, Arg1, and Arg2) and transport (Slc25a13, Slc25a15, and Slc3a2), whereas no such changes were found in the intestine. Our findings suggest that the genetic premature deletion of arginine synthesis in enterocytes causes a premature induction of the post-weaning pattern of amino-acid metabolism in the liver.     

Seasonality of reproduction in wild boar (Sus scrofa) assessed by fecal and plasmatic steroids

The collection of biological samples through non-invasive techniques represents one way of monitoring in vivo physiological changes associated with reproductive activity. Such techniques are particularly important for the study of animal species in the wild.The goals of this study were 1) to evaluate fecal progestogen (P), estrogen (E), and androgen (A) by means of radioimmunoassays, in male and female wild boars culled in the Piedmont, Italy area; 2) to compare them with plasmatic concentrations and the animals’ reproductive status; and 3) to assess variations in reproductive seasonality between two populations of wild boars living in a mountainous vs. a plain habitat in Piedmont.The results demonstrate a positive correlation between fecal and plasmatic steroid concentrations (r = 0.46, 0.58, and 0.45 for plasma P₄ and P, E₂ and E, and T and A; P < 0.05). Moreover, high fecal levels of both P and E (>170 ng/g and >100 pg/g respectively) were found in 70.6% of pregnant sows and in none of the non-pregnant animals, thus supporting the use of this technique for detecting pregnancy status in wild boar.Similar birth patterns were displayed by the mountain and plain populations, but births peaked significantly only in the mountain population, in the spring (46%, P < 0.05, vs. other seasons). A corresponding autumnal peak of plasma testosterone concentrations in males was displayed only by the mountain population (7.4 vs. < 2.0 ng/mL in the other seasons, P < 0.05).The correlation between fecal and plasmatic steroid concentrations obtained in this study supports the applicability of this non-invasive sampling technique for monitoring reproductive status in wild boar, thus enabling a more informed and correct management of the species.     

Studies on the activity of brown adipose tissue in suckling,pre-obese, obob mice

The properties and activity of brown adipose tissue have been investigated in suckling, pre-obese, $\text{ob}\text{ob}$ mice in order to determine whether decreased thermogenesis in the tissue precedes the development of obesity in this mutant. At 14 days of age there was no difference between the $\text{ob}\text{ob}$ and normal animals in the total amount of interscapular brown adipose tissue, and the DNA content, protein content, and cytochrome oxidase activity of the tissue were similar in the two groups of mice. Respiration rates of brown adipose tissue mitochondria in the presence of albumin were, however, greater in the normal than the $\text{ob}\text{ob}$ animals, although after the addition of GDP to recouple the mitochondria there was no difference between the two groups. The mitochondrial membrane potential, measured with [³H]methyltriphenylphosphonium, was less affected by exogenous GDP in $\text{ob}\text{ob}$ mice than in normal animals. GDP binding to brown adipose tissue mitochondria, an index of the proton conductance pathway, was much greater in normal than in $\text{ob}\text{ob}$ mice at both 10 and 14 days of age; the decreased GDP binding in the mutant animals was found to result from a reduction in the number of binding sites. It is concluded that brown adipose tissue mitochondria of pre-obese $\text{ob}\text{ob}$ mice are more tightly coupled than those of normal siblings, and that the activity of the ‘thermogenic’ proton conductance pathway is lower in the mutant animals. A decrease in thermogenesis in brown adipose tissue is therefore an early event in the development of the $\text{ob}\text{ob}$ mouse and precedes the appearance of obesity.     

Quantification of Alternaria,Cladosporium, Fusarium and Penicillium verrucosum in Conventional and Organic Grains by qPCR

We analysed the levels of Alternaria, Cladosporium, Fusarium and Penicillium verrucosum in grain samples harvested in 2011 and 2012 from conventional and organic farms using qPCR. In general, both Alternaria and Cladosporium occurred in all cereal grains in the highest quantities, followed by P. verrucosum and Fusarium. Alternaria, Cladosporium and P. verrucosum had the highest levels in crop mixtures, barley and rye and lower levels in wheat, while Fusarium levels were the highest in crop mixtures and wheat. The levels of Alternaria and P. verrucosum were higher in organic rye and wheat than conventional grains. Although the level of Fusarium was higher in conventional than organic rye, opposite results were obtained for crop mixtures. A positive correlation was found between Alternaria, Cladosporium and P. verrucosum, indicating that similar factors might affect the distribution of these fungi in grains.