Ultrastructure of the anal sacs in <Emphasis Type="Italic">Thalassema</Emphasis><Emphasis Type="Italic">thalassemum</Emphasis> (Annelida,Echiura)

The anal sacs of Thalassema thalassemum consist of an elongate tubular invagination (end sac) that is uniformly covered with numerous sessile ciliated funnels. While the funnels are composed of multi-ciliated, non-muscular cells and possess a ciliated neck-like constriction, the end sacs are lined by a simple epithelium of large, irregularly formed and sparsely ciliated cells that include masses of secretory granules. Podocytes are incorporated in the peritoneum that surrounds the anal sacs. A muscle grid consisting of inner longitudinal, outer circular and additional diagonal fibres that branch off of the circular fibres is embedded in the matrix between the end sac epithelium and peritoneum. Major structural differences between the hindgut and anal sacs support the hypothesis that the anal sacs are not gut derivatives but are instead part of a modified metanephridial system. Comparison of the anal sac morphology in Echiura reveals that T. thalassemum shares a tubular end sac with all known members of Thalassematinae and Ikedaidae, as well as with some members of Bonelliidae and Echiurinae, while the sessile funnels are apomorphic for the Thalassematinae.     

Three nephromixial patterns in polychaete species currently assigned to the genus Pista (Annelida,Terebellidae)

A comparative morphological study of nephromixial systems in three Californian terebellid polchaetes currently assigned to the genus Pista shows that P. fimbriata has all attributes of the generic type, but that P. pacifica and P. elongata differ markedly. The features of typical Pista include (among others): two pairs of usually unequal branchiae, long-handled anterior uncini (hooks) of crested avicular (bird-head-like) from, muddy, unornamented tubes, one pair of anterior excretory nephromixia (ENMX), and two pairs of separate thoracic reproductive nephromixia (RNMX) with genital papillae on segments VI and VII. A review indicates that P. fimbriata shares these typical features with practically all adequately described Pista species. However, P. pacifica and P. elongata possess three pairs of branchiae, long-handled uncini of distinctive crochet-like form, and membranous tubes with apertural hoods. Both have two pairs of ENMX, the first supplied by one pair of ciliated renal funnels, the second by two pairs of such funnels. But they differ in their RNMX: P. pacifica has three pairs of complex RNMX, those on each side united by a common duct. P. elongata has 11–13 pairs of simple RNMX united by common ducts. Although these species do not fit into Pista, no genus has been found to accommodate them. Generic placement is complicated by the fact that no instances of intra-generic nephromixial variation have been reported in the Terebellidae, although inter-generic variation is well known. If they are congeneric, this would be the first example of intrageneric RNMX variation in Terebellidae. But if assigned to separate genera or subgenera on the basis of their RNMX, their similarity of anterior uncini might be attributable to parallel or convergent adaptation to life in comparable tubes. More evidence, including molecular analysis, is needed for phylogenetic studies of Terebellidae. © 1992 Wiley-Liss, Inc.     

Antiplatelet pyrazolopyridines derivatives: pharmacological,biochemical and toxicological characterization

Platelet aggregation is one of the main events involved in vascular thrombus formation. Recently, N′-substituted-phenylmethylene-3-methyl-1,6-diphenyl-1H-pyrazolo[3,4-b]pyridine-4-carbohydrazides were described as antiplatelet derivatives. In this work, we explore the properties of these antiplatelet agents through a series of pharmacological, biochemical and toxicological studies. The antiplatelet activity of each derivative was confirmed as 3a, 3b and 3?h significantly inhibited human platelet aggregation induced by arachidonic acid, with no detectable effect on clotting factors or healthy erythrocytes. Importantly, mice treated with derivative 3a showed a higher survival rate at an in vivo model of pulmonary thromboembolism with a lower bleeding risk in comparison to aspirin. The in silico studies pointed a series of structural parameters related to thromboxane synthase (TXS) inhibition by 3a, which was confirmed by tracking plasma levels of PGE₂ and TXB₂ through an in vitro enzyme immunoassay. Derivative 3a showed selective TXS inhibition allied with low bleeding risk and increased animal survival, revealing the derivative as a promising candidate for treatment of cardiovascular diseases.     

Occurrence of hypogean trechine beetles in Hanzhong Tiankeng Cluster,southwestern Shaanxi,China (Coleoptera: Carabidae: Trechinae)

Qianaphaenops (Tiankengius) xigouicus Tian & Huang, n. subgen., n. sp. is described from a limestone cave in the Hanzhong Tiankeng Cluster, southwestern Shaanxi Province in the western part of Daba Shan Mountains, northern China. Tiankengius n. subgen. is related to Qianaphaenops (s. str.) Uéno, 2000 (a lineage of Guizhaphaenops Complex which ranges in northeastern Guizhou Province) instead of the genera Boreaphaenops Uéno, 2002 Yanzaphaenops Uéno, 2010 which are known from Shennongjia (eastern range of Daba Shan Mountains). However, Tiankengius is markedly distinct by several important features from Qianaphaenops. This is the first report of a troglobitic trechine beetle from Shaanxi Province, northern China.     

Syntheses of Alarm Pheromone Analogues of the Mold Mite,Tyrophagus putrescentiae,and Their Biological Activities

Against the mold mite, Tyrophagus putrescentiae, 3,7-dimethyl-(Z)-2-octenyl formate (II) is the most active compound as an alarm pheromone besides the natural pheromone, neryl formate (I), and this activity is equal to I (1-10 ppm). In order to elucidate the structural requisites for inducing alarm pheromone activity, a total of 16 analogues of I were prepared by modifying the structure of II. For preparation of 3-methyl- and 3-ethyl-(Z)-2-alkenyl formates, the Wittig reaction of ethoxy- or methoxy-carbonylmethylene triphenyl phosphorane with 2-alkanone or 3-alkanone was used. The reaction with 2-alkanone gave a mixture of (Z)-2-alkenoate (ca. 40%) and (E)-2-alkenoate (ca. 60%) in an average 60% yield. The reaction with 3-alkanone gave a mixture of (Z)-2-alkenoate (56%) and (E)-2-alkenonate (44%).

Alarm pheromone activities were demonstrated on 14 compounds of (Z)-2-alkenyl formates. The presence of the (Z)-allylic primary alcohol formate moiety in a molecule was clarified as the key to induce pheromone activity, and no necessity for an acyclic monoterpene carbon skeleton was demonstrated.     

Funnels,gas exchange and cliff jumping: natural history of the cliff dwelling ant Malagidris sofina

The Malagasy endemic ant Malagidris sofina (Bolton and Fisher 2014) nests on cliff faces in natural rock alcoves or clay banks. Colonies have single ergatoid queens and reproduce by fission. Each nest has a funnel-shaped entrance that projects horizontally from the cliff face. We examine three hypotheses for the function of the funnels—water exclusion, gas exchange and defense. Entrance funnels are relatively impermeable and divert water from nests, but simple tubes would achieve the same result. Consistent with the gas exchange hypothesis, projected funnel entrances likely increase gas exchange rates over sixfold compared to simple tubes and may increase air flow within the nest. Gas exchange may explain the recurrent evolution of funnel entrances in several ant lineages, especially among cliff dwelling species. We outline M. sofina defense responses to conspecifics and co-occurring ant species, and find no support for a defense role of entrance funnels. Workers display little aggression but respond to several species with an original form of nest defense––cliff jumping—in which workers drop off the cliff face while clinging to invaders and then return to their nest. M. sofina is a restricted range species under threat of extinction by habitat destruction. Its novel lifestyle underscores the urgency of exploration and conservation in a tropical biodiversity hotspot.     

Vegetation,microclimate and soils associated with the latest-lying snowpatches in Australia

Background : The Snowy Mountains contain Australia's longest-lasting snowpatches. Because of climate change, their longevity has declined, with the loss of some specialist vegetation in the underlying snowbeds.

Aims: To characterise the current status of the vegetation associated with the longest-lasting snowpatches in Australia and its association with abiotic factors.

Methods: We assessed plant composition, soil depth, moisture and nutrients and subsurface temperatures in five zones of increasing vegetation height and cover in snowbeds.

Results: The zone beneath the middle of snowpatches was characterised by little vegetation cover and lower species richness, later emergence from snow, skeletal soils, and lower mean soil temperatures than zones further downslope where soils increased in depth and nutrient levels. Vegetation beneath these snowpatches no longer occurs in distinct communities. Plants have not simply migrated upslope, instead, areas that have deep soil that used to have snowpatch specialist species are being colonised upslope by grasses and downslope by tall alpine herbfield species that prefer bare ground.

Conclusions: Reduced longevity of Australia's longest-lasting snowpatches has led to the loss of distinct snowpatch plant communities. With limited soils beneath the centre of current snowpatches, and a lack of other suitable sites there is no location for these plant communities to migrate to.     

Migratory Orientation of Blackcaps (Sylvia atricapilla): Population-specific Shifts of Direction during the Autumn

The population-specific orientation of two groups of blackcaps (Sylvia atricapilla), one from southwest Germany, the other from easternmost Austria, was studied outdoors in Emlen funnels. We investigated whether a seasonal shift in the migratory direction — as expected for the Austrian birds from ringing recoveries — occurs under experimental conditions and in a seasonally constant magnetic field. The West German birds, for which no shift was expected, oriented southwest during the entire season. The Austrian birds oriented southeast in October and southsouthwest in November. The clockwise shift by about 60° occurred within a 10-day period. The results indicate that in this species seasonal changes of migratory direction are probably based on an endogenous program, occur without the birds actually migrating and are independent of changes in the magnetic field. Our results provide further evidence that directional shifts in Sylvia warblers may be controlled by a different mechanism than in pied flycatchers (Ficedula hypoleuca).     

Desferrithiocin analogue iron chelators: iron clearing efficiency,tissue distribution,and renal toxicity

The current solution to iron-mediated damage in transfusional iron overload disorders is decorporation of excess unmanaged metal, chelation therapy. The clinical development of the tridentate chelator deferitrin (1, Table 1) was halted due to nephrotoxicity. It was then shown by replacing the 4′-(HO) of 1 with a 3,6,9-trioxadecyloxy group, the nephrotoxicity could be ameliorated. Further structure–activity relationship studies have established that the length and the position of the polyether backbone controlled: (1) the ligand’s iron clearing efficiency (ICE), (2) chelator tissue distribution, (3) biliary ferrokinetics, and (4) tissue iron reduction. The current investigation compares the ICE and tissue distribution of a series of (S)-4,5-dihydro-2-[2-hydroxy-4-(polyether)phenyl]-4-methyl-4-thiazolecarboxylic acids (Table 1, 3–5) and the (S)-4,5-dihydro-2-[2-hydroxy-3-(polyether)phenyl]-4-methyl-4-thiazolecarboxylic acids (Table 1, 8–10). The three most effective polyether analogues, in terms of performance ratio (PR), defined as mean ICE_primate/ICE_rodent, are 3 (PR 1.1), 8, (PR 1.5), and 9, now in human trials, (PR 2.2). At the onset of the clinical trial on 9, no data were available for ligand 3 or 8. This is unfortunate, as 3 has many advantages over 9, e.g., the ICE of 3 in rats is 2.5-fold greater than that of 9 and analogue 3 achieves very high levels in the liver, pancreas, and heart, the organs most affected by iron overload. Finally, the impact of 3 on the urinary excretion of kidney injury molecule-1 (Kim-1), an early diagnostic biomarker for monitoring acute kidney toxicity, has been carried out in rats; no evidence of nephrotoxicity was found. Overall, the results suggest that 3 would be a far superior clinical candidate to 9.     

Synthesis of mixed N,N′-(Ar,Ar′-diaryl)iminoisoindolines for applications in palladacycle formations

The synthesis of N,N′-(Ar,Ar′-diaryl)iminoisoindolines containing different aryl groups bound to the two nitrogen atoms is described. The iminoisoindolines were obtained by a three component, one-pot reaction of phthalaldehyde with 1 equivalent p-NO₂-aniline and 1 equivalent p-R-aniline, where R = H, Me, MeO or ⁱPr, resulting in formation of non-symmetrically substituted (mixed) iminoisoindolines, 1-p-nitrophenylimino-2-p-R-phenylisoindoline (R = H (1), Me (2), MeO (3), and ⁱPr (4)), as analytically pure precipitates requiring no further purification. Only one isomer precipitates from solution wherein the nitro group resides exclusively at the imine position while the more electron donating substituent ends up on the isoindoline ring position. Further reaction with Pd(OAc)₂ in dichloromethane at room temperature results in formation of six-membered [C,N] dinuclear cyclopalladated complexes with the general formula [(Ar,Ar′-diaryliminoisoindoline)Pd{μ-OAc}]₂.     

诺卡氏菌烈性噬菌体vB_Ncarnea_KYD1的分离纯化与基因组分析

【背景】诺卡氏菌是一种广泛分布的好氧放线菌,可在人体内引起局部或播散性感染,尤其是在免疫功能低下的个体中。诺卡氏菌感染在临床上较难鉴定,而且不断有新型诺卡氏菌种被发现。不同类型、不同地域的诺卡氏菌具有流行差异和抗生素敏感性差异,阻碍了适当治疗方式的选择。利用病灶处的宿主菌分离得到噬菌体来控制诺卡氏菌感染的这种方法在近年来受到了各界的关注。【目的】尝试从环境中分离出能够用于临床治疗的针对诺卡氏菌的烈性噬菌体,并研究其基因组学特征。【方法】利用双层平板法分离得到目标噬菌体,观察其噬菌斑形态,并对噬菌体进行分离纯化,在透射电镜下鉴定其特征。提取噬菌体DNA进行全基因组测序与注释,并与数据库内已知噬菌体基因组进行比较,同时构建系统进化树以进行遗传进化分析。【结果】本文以肉色诺卡氏菌为宿主,从环境样本中分离出一株烈性噬菌体vB_Ncarnea_KYD1,在双层平板上可形成直径<2 mm的透亮均匀的噬菌斑。基因组分析表明,vB_Ncarnea_KYD1DNA为环状,大小为66 621 bp,共发现102个蛋白质编码区(coding sequence,CDS)及一个tRNA-Ser编码序列。透射电镜观察与系统进化树综合分析可以确定,vB_Ncarnea_KYD1为长尾噬菌体科的一个新属。其在进化过程中经历了复杂的基因重组过程。暂未发现毒力因子相关基因与抗性基因,具备实用价值。【结论】从环境水体中分离出一株烈性肉色诺卡氏菌噬菌体vB_Ncarnea_KYD1,通过电镜观察与基因组分析可知,此株噬菌体为长尾噬菌体,基因组中暂未发现不利于临床应用的相关基因,是一株相对安全的烈性诺卡氏菌噬菌体。研究结果丰富了国内噬菌体资源库,并为后续诺卡氏菌感染疾病的治疗提供支持。     

Synthesis,in vitro and in vivo antitumor and antiviral activity of novel 1-substituted benzimidazole derivatives

Abstract

A novel series of 5-nitro-1H-benzimidazole derivatives substituted at position 1 by heterocyclic rings was synthesized. Cytotoxicity and antiviral activity of the new compounds were tested. Compound 3 was more active than doxorubicin against A-549, HCT-116 and MCF-7. However, compound 3 showed no activity against human liver carcinoma Hep G-2 cell line. Compounds 9 and 17b (E) showed potency near to doxorubicin against the four cell lines. The acute toxicity of compound 9 on liver cancer induced in rats was determined in vivo. Interestingly, it showed restoration activity of liver function and pathology towards normal as compared to the cancer-bearing rats induced by DENA. Compounds 17a (Z), 17b (E) and 18a (Z) were the most promising compounds for their antiviral activity against rotavirus Wa strain.     

伊犁野生郁金香内生烟曲霉的分离鉴定及活性

【背景】对郁金香的研究主要集中在种质资源、引种栽培、扩繁育种及化学成分分析方面,而关于伊犁野生郁金香内生菌的研究尚未见报道。【目的】从伊犁野生郁金香中筛选出内生真菌并对其进行抑菌及抗氧化活性研究。【方法】采用组织块培养法和平板划线法对伊犁野生郁金香内生菌进行分离纯化;用斜面低温保存法对内生菌进行保存;以形态学方法和分子生物学方法对分离出的内生真菌进行鉴定;通过液体发酵得到次级代谢产物,对乙酸乙酯萃取发酵产物进行滤纸片抑菌分析。使用Fe3+总还原能力法、2-2′二苯基-1-三硝基苯肼(2,2′-diphenyl-1-picrylhydrazyl,DPPH)自由基法、 2′-联氨-双-3-乙基苯并噻唑啉-6-磺酸[2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonicacid,ABTS]自由基法及羟基自由基法比较菌株乙酸乙酯层和水层的抗氧化活性。【结果】从伊犁野生郁金香中分离获得一株内生真菌,经鉴定为曲霉属(Aspergillus)烟曲霉(Aspergillus fumigatus),简称为YGL-1。YGL-1对金黄色葡萄球菌(Staphylo...     

牦牛源产细菌素屎肠球菌的分离鉴定和益生特性

【背景】抗生素的滥用导致牦牛肠道常见病原菌耐药性增加,益生菌作为对抗耐药性细菌的新型武器,应用前景广阔。【目的】获取益生特性优良的牦牛源益生菌。【方法】将20份牦牛粪便样本在含0.5%CaCO3的MRS培养基上分离纯化,以大肠杆菌和金黄色葡萄球菌为指示菌,用牛津杯法筛选有抑菌活性的菌株;排除酸和过氧化氢后,经耐酸耐热试验和蛋白酶敏感试验筛选产细菌素菌株,用形态学和16S rRNA基因序列分析鉴定;通过对大肠杆菌、沙门氏菌等腹泻病原菌体外抑菌试验、耐模拟胃肠液、测定自聚集能力和疏水性及抗生素敏感试验分析益生特性。【结果】从20份牦牛粪便样本中共分离出11株产生溶钙圈的菌株,其中6株对大肠杆菌和金黄色葡萄球菌抑菌效果显著,经复筛得到2株产细菌素的乳酸菌SC6和SC9,经鉴定均为屎肠球菌(Enterococcus faecium)。其中SC9对腹泻病原菌抑菌效果明显,有良好的耐受性和肠道黏附能力,对5种常用抗生素均敏感。【结论】屎肠球菌SC9有一定的抗逆性和潜在的益生能力,具备作为益生菌的潜力。     

Community Structure,Geochemical Characteristics and Mineralogy of a Hypersaline Microbial Mat,Cabo Rojo,PR

Seasonal variations in precipitation changed the community composition and microbial activity in a hypersaline, tropical microbial mat, in Cabo Rojo, PR. Using a combination of dissection, light, and transmission electron microscopy, terminal restriction fragment length polymorphism (T-RFLP), in situ microelectrode studies, and ³⁵ S isotope incubations, we documented the major differences between wet and dry seasons. During the wet season (precipitation 177 mm), cyanobacterial (green layer) and anoxyphototrophic (pink layer) communities, as well as the black FeS layer were well-developed, and T-RFLP patterns indicated a diverse community. The rate of oxygenic photosynthesis was 49 μ M min ^{? 1} . Aerobic respiration was 29 μ M min ^{? 1} , and sulfate reduction was 264 nmol cm ^{? 3} h ^{? 1} . During the dry season (precipitation 51 mm), cyanobacteria and anoxyphototrophs were less diverse and abundant, and T-RFLP patterns were less complex. The O ₂ production rate was reduced to 9 μ M min ^{? 1} , as was O ₂ consumption (7 μ M min ^{? 1} ) and sulfate reduction (26 nmol cm ^{? 3} h ^{? 1} ). Aragonite, calcite, halite, and quartz were the predominant minerals. Seasonal differences were found in the green and pink layers for both halite and quartz. Gypsum was not observed, likely due to a sample handling artifact. The fluctuations in community composition and metabolic activity, principally reflected in fluctuations in binding and trapping potential of the uppermost mat community, might be responsible for the observed differences in mineralogy.     

加州鲈源鰤鱼诺卡氏菌的分离鉴定及致病性

[背景] 鰤鱼诺卡氏菌（Nocardia seriolae）是一种严重危害水产养殖业的病原菌,可引起以体表溃疡、出血及组织器官形成结节为特征的鱼类慢性肉芽肿疾病,目前尚无有效的防治方法。[目的] 明确引起安徽省临泉县某养殖场加州鲈（Micropterus salmonoides）结节病的病原菌,探讨其致病性,为该病的有效防治提供科学依据。[方法] 取肝脏结节病灶接种于TSB培养基分离优势细菌,利用表型检查结合分子生物学方法鉴定分离菌株。进一步通过检测分离菌株的毒力基因、测定其对加州鲈的半数致死量（LD₅₀）以及所感染加州鲈的组织病理学变化与组织载菌量,分析其致病性。[结果] 从病鱼体内分离到一株优势菌株NI,综合NI分离株的表型特性、16S rRNA基因序列与鰤鱼诺卡氏菌参考株相应序列的一致性以及特异性PCR扩增结果,确定其为鰤鱼诺卡氏菌。鰤鱼诺卡氏菌NI分离株携带毒力基因gapA、ibeA和mip,人工回归感染后加州鲈出现与自然病例相似的症状,其对加州鲈的LD₅₀为2.58×10⁶ CFU/尾。组织病理学观察到头肾、心脏、肝脏、胃和脾脏均出现慢性肉芽肿病变,肠管肌层疏松、肠绒毛脱落,肌肉组织中肌纤维疏松、间隙增宽。qPCR检测结果显示,组织中鰤鱼诺卡氏菌载量由高到低依次为头肾、心、肝、胃、脾、肠和肌肉。[结论] 鰤鱼诺卡氏菌是引起此次加州鲈结节病的病原菌,对该菌致病性的研究为加州鲈诺卡氏菌病的防控提供了理论依据。     

Crop presence,but not genetic diversity,impacts on the rare arable plant Valerianella rimosa

Background: Intensive farming affects farmland biodiversity, and some arable plants in particular. Increasing crop genetic diversity can increase crop productivity or resilience and could also benefit rare arable plants.

Aims: We examined whether barley presence, sowing density and genetic diversity impacted the rare plant Valerianella rimosa and explored possible underlying mechanisms.

Methods: In a field study near Dundee, Scotland, we sowed plots of five single barley genotypes, and all five genotypes combined, at three densities; we also had barley-free plots. Valerianella seeds were sown into half of all plots. Measured responses included early-season cover and harvest biomass of barley and common weeds, abiotic parameters (soil moisture, light) and establishment, biomass and seed production by V. rimosa.

Results: Barley presence promoted V. rimosa establishment early in the growing season, but without barley density or genetic diversity effects. By harvest, the impact of barley presence on V. rimosa abundance was lost; there were no effects on Valerianella seed production. Barley negatively impacted common weeds, but V. rimosa did not benefit from any indirect facilitation by barley, being bigger without barley.

Conclusions: Early beneficial effects of barley on V. rimosa abundance appear offset by late-season competition. However, limited impacts of barley on V. rimosa reproductive success, and negative impacts on common weeds, indicate crops might play a role in conservation management of rare arable plants by creating space in the weed community.     

Chromosomal relationships of heterochromatin bodies in a moss,Dicranum tauricum Sapehin

Abstract

The largest bivalent in a population of Dicranum tauricum with the haploid chromosome number of n = 12 was found to divide precociously during meiosis. Since it contained no constitutive heterochromatin, as revealed by a Giemsa C-banding technique, it could not be identified as an H-chromosome. A large body of predominantly facultative heterochromatin was recognized in gametophytic mitotic and pre-meiotic interphase cells and was possibly a composite structure. During these stages, a small block of constitutive heterochromatin was associated with the nucleolus. It was related to a chromosome which, because it was not the smallest member of the complement, could not be called an H-chromosome. Consequently, a reassessment of H- and H-chromosomes in mosses is recommended.