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1.
A new species, Overstreetia olsoni, is described from Atherinomorus capricornensis off Heron Island on the Great Barrier Reef off Queensland, Australia. It differs from its only known congener in that the enlarged spines of the circum-oral rows are smaller ( ≤ 4.5 × 3.5 vs ≤ 21.5 × 10.5μm), the sucker-ratio is smaller (1: 0.97–1.01 vs 1:1.8) and the eggs are larger (40–45 × 22–28 vs 34–37 × 17–22μm).  相似文献   

2.
Proctotrema bartolii n. sp. (Digenea: Monorchiidae) is described based on naturally and experimental obtained adults from the marine fishes Odontesthes smitti (Lahille), O. nigricans (Richardson) (Atherinopsidae) and Eleginops maclovinus (Cuvier) (Eleginopidae) off Patagonia, Argentina, in the Southwestern Atlantic Ocean. Its generic identification is based on the presence of a unipartite terminal organ with the metraterm uniting with its distal region, an unarmed genital atrium, a single testis, a vitellarium follicular lateral to the ovary and ventral sucker, and uterine coils occupying most of hindbody. The new species differs from P. bacilliovatum Odhner, 1911, P. amphitruncatum Fischthal & Thomas, 1969 and P. guptai Ahmad & Dhar, 1987 in having a smaller body (305–650 vs 1,600–3,080, 1,500–1,800 and 2,150–2,670 μm, respectively), a round vs funnel-shaped oral sucker, a smooth vs lobed ovary, a saccular rather than tubular excretory vesicle, the number of vitelline follicles (12–16 vs 8–9, 9 and 6–8, respectively), and wider eggs (25–31 × 15–20 vs 28–37 × 9–12, 24–28 × 7–10, and 24–30 × 8–10 μm, respectively). Moreover, the new species differs from P. bacilliovatum and P. amphitruncatum in having a saccular rather than a coiled seminal vesicle, and from P. bacilliovatum and P. guptai in having its tegument completely vs partly spined. Proctotrema Odhner, 1911 is considered to be restricted to these four species. This is the first report of a species of this genus from South American waters.  相似文献   

3.
A new lecanicephalidean species of Aberrapex Jensen, 2001 is described from the blue-spotted fantail ray Taeniura lymma (Forsskål) collected off the eastern coast of Sabah in Malaysian Borneo. This is the first record of a lecanicephalidean tapeworm from the island of Borneo and the first record of Aberrapex from this host species. A. manjajiae n. sp. is easily distinguished from its two congeners, A. senticosus Jensen, 2001 and A. arrhynchum (Brooks, Mayes & Thorson, 1981) Jensen, 2001, based on its overall smaller size (928–1,971 vs 1,485–6,333 and up to 3,350μm long, respectively) and fewer testes (10–19 vs 20–40 and 18–25, respectively). In addition, A. manjajiae n. sp. is readily distinguished from A. senticosus based on a more anteriorly positioned genital pore (76–85 vs 52–72% of proglottid length from posterior end) and its distal bothridial microthrix pattern. A. manjajiae n. sp. can be further distinguished from A. arrhynchum based on its smaller scolex (82–101 × 119–164 vs 177–186 × 233–326μm). The host distribution of Aberrapex is expanded from the Myliobatidae to include the Dasyatidae.  相似文献   

4.
Two new species of the cryptogonimid genus Parspina Pearse, 1920 are described from gymnotiform fishes of the Paraná River basin, P. carapo n. sp. from the banded knifefish Gymnotus carapo Linnaeus and P. virescens n. sp. from the glass knifefish Eigenmannia virescens (Valenciennes). Parspina carapo differs from P. virescens in the number of oral spines (32–39 vs 30–33) and their length (28–47 vs 16–28 μm), the distribution of tegumental spines and their anchorage, the types of sensory papillae on the body surface (three vs two types), the extent of body length posterior to the caeca (5 vs 13% of the total body length), the dimensions of the pars prostatica (52 × 34 vs 24 × 10 μm), and in the absence of a gonotyl (vs presence). Both P. carapo and P. virescens differ from P. bagre Pearse, 1920 and P. argentinensis (Szidat, 1954) in the number of oral spines (20–21 and 21–28 in the latter pair) and their length (28–32 and 35–60 μm), and in total body length. Additionally, the two new species differ from P. argentinensis in the arrangement of the vitelline follicles (one continuous band vs two groups on each side of the body) and in having a smaller pars prostatica (149 × 49 μm in the latter). Parspina carapo is the fifth intestinal helminth found in G. carapo, and P. virescens is the first found in E. virescens.  相似文献   

5.
The understanding of how pain is processed at each stage in the peripheral and central nervous system is the precondition to develop new therapies for the selective treatment of pain. In the periphery, ATP can be released from various cells as a consequence of tissue injury or visceral distension and may stimulate the local nociceptors. The highly selective distribution of P2X3 and P2X2/3 receptors within the nociceptive system has inspired a variety of approaches to elucidate the potential role of ATP as a pain mediator. Depolarization by ATP of neurons in pain–relevant neuronal structures such as trigeminal ganglion, dorsal root ganglion, and spinal cord dorsal horn neurons are well investigated. P2X receptor-mediated afferent activation appears to have been implicated in visceral and neuropathic pain and even in migraine and cancer pain. This article reviews recently published research describing the role that ATP and P2X receptors may play in pain perception, highlighting the importance of the P2X3 receptor in different states of pain.  相似文献   

6.
The psbA-trnH intergenic region is among the most variable regions in the angiosperm chloroplast genome. It is a popular tool for plant population genetics and species level phylogenetics and has been proposed as suitable for DNA barcoding studies. This region contains two parts differing in their evolutionary conservation: 1) the psbA 3′UTR (untranslated region) and 2) the psbA-trnH intergenic non-transcribed spacer. We compared the sequence and RNA secondary structure of the psbA 3′ UTR across angiosperms and found consensus motifs corresponding to the stem portions of the RNA stem-loop structures and a consensus TTAGTGTATA box. The psbA-trnH spacer exhibited patterns that can be explained by the independent evolution of large inversions in the psbA 3′UTR and mutational hot spots in the remaining portion of the psbA-trnH spacer. We conclude that a comparison of chloroplast UTRs across angiosperms offer clues to the identity of putative regulatory elements and information about selective constraints imposed on the chloroplast non-coding regions.  相似文献   

7.
8.
Irradiance data software developed by the NREL Solar Radiation Laboratory (Simple Model of Atmospheric Radiative Transfer of Sunshine, SMARTS) has been used for modelling photosynthesis. Spectra and total irradiance were expressed in terms of quanta [mol m−2 s−1, photosynthetic photon flux density, PPFD (400–700 nm)]. Using the SMARTS software it is possible to (1) calculate the solar spectrum for a planar surface for any given solar elevation angle, allowing for the attenuating effects of the atmosphere on extraterrestrial irradiance at each wavelength in the 400–700 nm range and for the thickness of atmosphere the light must pass through during the course of a day, (2) calculate PPFD vs. solar time for any latitude and date and (3) estimate total daily irradiance for any latitude and date and hence calculate the total photon irradiance for a whole year or for a growing season. Models of photosynthetic activity vs. PPFD are discussed. Gross photosynthesis (P g) vs. photosynthetic photon flux density (PPFD) (P g vs. I) characteristics of single leaves compared to that of a canopy of leaves are different. It is shown that that the optimum irradiance for a leaf (Iopt) is the half-saturation irradiance for a battery of leaves in series. A C3 plant, with leaves having an optimum photosynthetic rate at 700 μmol m−2 s−1 PPFD, was used as a realistic worked example. The model gives good estimates of gross photosynthesis (P g) for a given date and latitude. Seasonal and annual estimates of P g can be made. Taking cloudiness into account, the model predicts maximum P g rates of about 10 g(C) m−2 d−1, which is close to the maximum reported P g experimental measurements.  相似文献   

9.
Injury to the peripheral nervous system can lead to spontaneous pain, hyperalgesia and allodynia. Previous studies have shown sprouting of Aβ-fibres into lamina II of the spinal cord dorsal horn after nerve injury and the formation of new synapses by these sprouts. β-Catenin and menin as synaptogenic factors are critically involved in synapse formation. However, the roles of β-catenin and menin in neuropathic pain are still unclear. Using Western blot analysis we investigated the changes of β-catenin and menin in the spinal dorsal horn after unilateral spared nerve injury (SNI). We demonstrated an increase in both β-catenin and menin protein levels in the ipsilateral spinal dorsal horn at days 1 and 3 following spared nerve injury (P < 0.05). These increases were associated with changes in paw withdrawal threshold to mechanical stimuli and weight bearing deficit suggestive of pain behavior and spontaneous ongoing pain respectively. However, the injury-associated increases in β-catenins and menins levels returned to control levels at day 14. In conclusion, these results indicate that peripheral nerve injury induces upregulation of β-catenins and menins in the dorsal horn of the spinal cord, which may contribute to the development of chronic neuropathic pain. Antagonists of these molecules may serve as new therapeutic agents.  相似文献   

10.
Using a stochastic model, we found that the steady-state temporal correlation between synaptic responses evoked by successive presynaptic spikes under conditions of high-frequency repetitive stimulation (50–100 sec−1) is always negative. Therefore, the sign of this correlation cannot be used as a criterion that allows one to distinguish the univesicular vs multivesicular modes of neurotransmitter release in an active zone or the univesicular releases with low vs high probabilities of vesicle release, as suggested earlier [7]. For lower stimulation frequencies (15–20 sec−1), positive correlation between release events evoked by consecutive stimuli is observed only in those cases where the number of ready-releasable vesicles and the time constant of recovery from depression are sufficiently large. Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 412–415, September–December, 2006.  相似文献   

11.
Alterations in the expression of the neuropeptide, galanin, were examined in micturition reflex pathways of rat after cyclophosphamide (CYP)-induced cystitis of variable duration: acute (4 h), intermediate (48 h), or chronic (10 days). In control animals, galanin expression was present in specific regions of the gray matter in the rostral lumbar and caudal lumbosacral spinal cord, including: (1) the dorsal commissure (DCM); (2) superficial dorsal horn; (3) the regions of the intermediolateral cell column (L1–L2) and the sacral parasympathetic nucleus (SPN, L6–S1); and (4) the lateral collateral pathway (LCP) in lumbosacral spinal segments. Densitometry analysis demonstrated significant decreases (P≤0.01) in galanin immunoreactivity (IR) in these regions of the L1–S1 spinal cord after acute or intermediate CYP-induced cystitis. In contrast, increases (P≤0.01) in galanin–IR were observed in the DCM, SPN, or LCP regions in the L6–S1 spinal segments in rats with chronic cystitis. No changes in the number of galanin–immunoreactive cells were observed in the L1–S1 dorsal root ganglia (DRG) after CYP-induced cystitis of any duration. A small percentage of bladder afferent cells (Fast-blue-labeled) in the DRG expressed galanin–IR in control rats; this was not altered with cystitis. Galanin–IR was observed encircling DRG cells after chronic cystitis. These changes may contribute to urinary bladder dysfunction, altered sensation, and referred somatic hyperalgesia after cystitis.This work was supported in part through NIH grants DK051369, DK060481, DK065989, and NS040796.  相似文献   

12.
Neurotrophins and their receptors control a number of cellular processes, such as survival, gene expression and axonal growth, by activating multiple signalling pathways in peripheral neurons. Whether each of these pathways controls a distinct developmental process remains unknown. Here we describe a novel knock-in mouse model expressing a chimeric TrkA/TrkC (TrkAC) receptor from TrkA locus. In these mice, prospective nociceptors survived, segregated into appropriate peptidergic and nonpeptidergic subsets, projected normally to distinct laminae of the dorsal spinal cord, but displayed aberrant peripheral target innervation. This study provides the first in vivo evidence that intracellular parts of different Trk receptors are interchangeable to promote survival and maturation of nociceptors and shows that these developmental processes can be uncoupled from peripheral target innervation. Moreover, adult homozygous TrkAC knock-in mice displayed severe deficits in acute and tissue injury-induced pain, representing the first viable adult Trk mouse mutant with a pain phenotype.  相似文献   

13.
Iron can be involved in the pathogenesis of AMD through the oxidative stress because it may catalyze the Haber–Weiss and Fenton reactions converting hydrogen peroxide to free radicals, which can induce cellular damage. We hypothesized that genetic polymorphism in genes related to iron metabolism may predispose individuals to the development of AMD and therefore we checked for an association between the g.32373708 G>A polymorphism (rs867469) of the IRP1 gene and the g.49520870 G>A (rs17483548) polymorphism of the IRP2 gene and AMD risk as well as the modulation of this association by some environmental and life-style factors. Genotypes were determined in DNA from blood of 269 AMD patients and 116 controls by the allele-specific oligonucleotide-restriction fragment length polymorphism and the polymerase chain reaction-restriction fragment length polymorphism. An association between AMD, dry and wet forms of AMD and the G/G genotype of the g.32373708 G>A-IRP1 polymorphism was found (OR 3.40, 4.15, and 2.75). On the other hand, the G/A genotype reduced the risk of AMD as well as its dry or wet form (OR 0.23, 0.21, 0.26). Moreover, the G allele of the g.49520870 G>A-IRP2 polymorphism increased the risk of the dry form of the disease (OR 1.51) and the A/A genotype and the A allele decreased such risk (OR 0.43 and 0.66). Our data suggest that the g.32373708 G>A-IRP1 and g.49520870 G>A-IRP2 polymorphisms may be associated with increased risk for AMD.  相似文献   

14.
We studied changes in the power spectra of EEG in the course of sessions of feedback by EEG characteristics (neurofeedback sessions) and estimated the effects of neurofeedback on psychological and EEG correlates of voluntary attention. Indices of the latter were estimated using Bourdon’s test (a correcture test) and Schulte’s tables. Twenty-nine reasonably healthy 10-to 13-year-old children took part in the study; they were divided into two groups, an experimental group (n = 12) and a control group (n = 15). The results obtained support the statement on noticeable changes in the functional state of the brain both immediately in the course of a neurofeedback session and after a course of such trainings. Changes in the ratios of the spectral powers of the beta1 vs theta rhythms and the low-frequency beta vs theta rhythms were found in EEG recorded from the sensorimotor zone of the right hemisphere (C4). The observed changes in the spectral characteristics of EEG induced by the course of neurofeedback sessions were accompanied by the improvement of a few indices of voluntary attention. Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 458–465, September–December, 2006.  相似文献   

15.
 A dual marker plasmid comprising the reporter gene sgfp (green fluorescent protein) and the selectable bar gene (Basta tolerance) was constructed by replacing the uidA (β-glucuronidase, GUS) gene in a uidA-bar construct with sgfp. A particle inflow gun was used to propel tungsten particles coated with this plasmid into immature inflorescence-derived embryogenic callus of switchgrass (Panicum virgatum L.). GFP was observed in leaf tissue and pollen of transgenic plants. Nearly 100 plants tolerant to Basta were obtained from the experiments, and Southern blot hybridization confirmed the presence of both the bar and sgfp genes. Plants regenerated from in vitro cultures of transgenic plants grew on medium with 10 mg l–1 bialaphos. When the pH indicator chlorophenol red was in the medium, the transgenic plantlets changed the medium from red to yellow. Basta tolerance was observed in T1 plants resulting from crosses between transgenic and nontransgenic control plants, indicating inheritance of the bar transgene. Received: 11 May 2000 / Revision received: 21 August 2000 / Accepted: 22 August 2000  相似文献   

16.
The effect of applying Lactobacillus buchneri (LB), alone or in combinations with L. plantarum (LP) and yeasts at ensiling, on the ensiling fermentation and aerobic stability of wheat and sorghum silages was studied under laboratory conditions. Treatments comprised LB, LP, yeasts, LB + yeasts, LP + yeasts, LB + LP and B-589 (a lactic acid bacterial strain isolated from wheat silage in Israel) alone. The treatments were also applied to sterilized aqueous extracts of wheat which were incubated at 30°C for 10 days. The pH of all treatments was below 4.0 already on day 4 of the experiment. Silages treated with LB had higher acetic acid concentrations than those treated with LP: 32–34 vs 16–18, and 28–34 vs 4–7 g kg−1 in the experiments with wheat and sorghum, respectively. Similar results were obtained in wheat extracts. In the aqueous phase, marked differences in pH decrease were noticed among the treatments: 4.4 in LB, 6.0 in the yeast, and 3.7 in LP and B-589 (from day 3 and onwards). In both crops LB resulted in aerobically stable silages when applied alone or with LP and yeasts, whereas LP resulted in unstable silages upon aerobic exposure; the stability of the LB-treated silages is attributed to the higher acetic acid concentrations. The isolated strain (B-589) did not exhibit any advantage with regard to aerobic stability. Received 26 April 1999/ Accepted in revised form 05 July 1999  相似文献   

17.
The neural control of micturition undergoes marked changes during the early postnatal development. During the first few postnatal weeks, the spinal micturition reflex is gradually replaced by a spinobulbospinal reflex pathway that is responsible for micturition in adult animals. Upregulation of brainstem regulation of spinal micturition pathways may contribute to development of mature voiding patterns. We examined the expression of corticotropin-releasing factor (CRF), present in descending projections from Barrington's nucleus to the sacral parasympathetic nucleus (SPN), in postnatal (P0–P36) and adult Wistar rats (P60–90). CRF-immunoreactivity (IR) was present predominantly in the SPN region, although some staining was also observed in the dorsal horn and dorsal commissure in L5–S1 spinal segments. CRF-IR in spinal cord regions was age dependent (R 2=0.87–0.98). The majority of the CRF-IR in the lumbosacral spinal cord was eliminated by complete spinalization (2–3 weeks). Double-label immunohistochemistry was combined with quantitative confocal laser scanning microscopy to quantify the number and percentage of colocalization between CRF-immunoreactive varicosities and preganglionic somas or proximal neurites in the SPN in postnatal and adult rats. Results demonstrate an age-dependent upregulation of CRF-IR in the SPN region and specifically in association with preganglionic parasympathetic neurons identified with neuronal nitric oxide synthase (nNOS)-IR. CRF-immunoreactive varicosities on or within a 1 μm perimeter of nNOS-immunoreactive somas or proximal neurites also increased with postnatal age. The upregulation of CRF-IR in bulbospinal projections to the SPN may contribute to mature voiding reflexes. This work was supported in part through NIH grants DK051369, DK060481, DK065989, NS040796.  相似文献   

18.
The gene encoding malate dehydrogenase (MDH) was overexpressed in a pflB ldhA double mutant of Escherichia coli, NZN111, for succinic acid production. With MDH overexpression, NZN111/pTrc99A-mdh restored the ability to metabolize glucose anaerobically and 0.55 g/L of succinic acid was produced from 3 g/L of glucose in shake flask culture. When supplied with 10 g/L of sodium bicarbonate (NaHCO3), the succinic acid yield of NZN111/pTrc99A-mdh reached 1.14 mol/mol glucose. Supply of NaHCO3 also improved succinic acid production by the control strain, NZN111/pTrc99A. Measurement of key enzymes activities revealed that phosphoenolpyruvate (PEP) carboxykinase and PEP carboxylase in addition to MDH played important roles. Two-stage culture of NZN111/pTrc99A-mdh was carried out in a 5-L bioreactor and 12.2 g/L of succinic acid were produced from 15.6 g/L of glucose. Fed-batch culture was also performed, and the succinic acid concentration reached 31.9 g/L with a yield of 1.19 mol/mol glucose.  相似文献   

19.
The aim of the study is to examine thermal behavior of water within reticulated structure of bacterial cellulose (BC) films by sub-ambient differential scanning calorimetry (DSC). BC films with different carbon source, either manitol (BC (a)) or glycerol (BC (b)), were produced by Acetobacter xylinum using Hestrin and Shramm culture medium under static condition at 30 ± 0.2°C for 3 days. BC samples were characterized by electron scanning microscopy and X-ray diffraction spectroscopy. The pore analysis was done by B.H.J. nitrogen adsorption. The pre-treated with 100% relative humidity, at 30.0 ± 0.2°C for 7 days samples were subjected to a between 25 and −150°C-cooling–heating cycle of DSC at 5.00°C/min rate. The pre-treated samples were also hydrated by adding 1 μl of water and thermally run with identical conditions. It is observed that cellulose fibrils of BC (a) were thinner and reticulated to form slightly smaller porosity than those of BC (b). They exhibited slightly but non-significantly different crystalline features. The freezable bound water behaved as a water confinement within pores rather than a solvent of polymer which is possible to use thermoporosimetry based on Gibb–Thomson equation to approach pore structure of BC. In comparison with nitrogen adsorption, it was found that thermoporosimetry underestimated the BC porosity, i.e., the mean diameters of 23.0 nm vs. 27.8 nm and 27.9 nm vs. 33.9 nm for BC (a) and BC (b), respectively, by thermoporosimetry vs. B.H.J. nitrogen adsorption. It may be due to large non-freezable water fraction interacting with cellulose, and the validity of pore range based on thermodynamic assumptions of Gibb–Thomson theory.  相似文献   

20.
The aim of this research was to formulate Marsupsin–phospholipid complex (M–P Complex) in attempt to increase the bioavailability of marsupsin and to characterize this new formulation along with its evaluation. Marsupsin–phospholipid complex was formulated by mechanical dispersion method. In this new formulation, complex formation was confirmed by carrying out transmission electron microscopy (TEM), IR, 1H-NMR and RP-HPLC analysis. TEM showed M–P Complex diameter range of 0.05–0.5 μm. The entrapment efficiency of M–P Complex was found to be 44%. In vitro release study revealed its first order release profile. Mean blood serum concentration vs time curve of marsupsin was of first order after oral administration of M–P Complex in albino rabbits which clearly showed remarkably increased bioavailability of M–P Complex than standardized marsupsin. The average value of C max and T max of M–P Complex were found to be 3.02 mg/ml and 10.2 h, respectively. Hence the findings demonstrate that complexing marsupsin with phospholipids results in better oral bioavailability and improved biological response than free form of standardized marsupsin.  相似文献   

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