929 research outputs found
Signal detection in extracellular neural ensemble recordings using higher criticism
Information processing in the brain is conducted by a concerted action of
multiple neural populations. Gaining insights in the organization and dynamics
of such populations can best be studied with broadband intracranial recordings
of so-called extracellular field potential, reflecting neuronal spiking as well
as mesoscopic activities, such as waves, oscillations, intrinsic large
deflections, and multiunit spiking activity. Such signals are critical for our
understanding of how neuronal ensembles encode sensory information and how such
information is integrated in the large networks underlying cognition. The
aforementioned principles are now well accepted, yet the efficacy of extracting
information out of the complex neural data, and their employment for improving
our understanding of neural networks, critically depends on the mathematical
processing steps ranging from simple detection of action potentials in noisy
traces - to fitting advanced mathematical models to distinct patterns of the
neural signal potentially underlying intra-processing of information, e.g.
interneuronal interactions. Here, we present a robust strategy for detecting
signals in broadband and noisy time series such as spikes, sharp waves and
multi-unit activity data that is solely based on the intrinsic statistical
distribution of the recorded data. By using so-called higher criticism - a
second-level significance testing procedure comparing the fraction of observed
significances to an expected fraction under the global null - we are able to
detect small signals in correlated noisy time-series without prior filtering,
denoising or data regression. Results demonstrate the efficiency and
reliability of the method and versatility over a wide range of experimental
conditions and suggest the appropriateness of higher criticism to characterize
neuronal dynamics without prior manipulation of the data
3-Bromo-4-dibenzylamino-5-methoxyfuran-2(5H)-one
In the the title compound, C19H18BrNO3, the furanone ring is almost planar [maximum atomic deviation = 0.019 (3) Å] and is nearly perpendicular to the two phenyl rings, making dihedral angles of 88.96 (17) and 87.71 (17)°. Intermolecular C—H⋯O hydrogen bonding is present in the crystal structure
The first isolation of Aspergillus allahabadii from a cormorant with pulmonary aspergillosis
In this study, we report the first isolation of Aspergillus allahabadii from a Japanese cormorant with pulmonary aspergillosis. We performed molecular identification and antifungal susceptibility testing with the E-test. A 7-month-old male cormorant died because of uric acid deposition secondary to dehydration. Whitish nodular lesions were present on the caudal thoracic air sac in the right thoracic cavity. Histopathology revealed multifocal pyogranulomatous necrotic lesions with numerous fungal hyphae in the thoracic air sac. Identification of the etiologic agent was confirmed by comparative analyses of the sequences of the internal transcribed spacer (ITS) region and β-tubulin-encoding genes. According to the E-test, the minimum inhibitory concentrations of the isolate to amphotericin B, fluconazole, itraconazole, and voriconazole were 0.75 μg/ml, >256 μg/ml, 0.38 μg/ml, and 0.38 μg/ml, respectively
A Randomized Pilot Study of Atractylenolide I on Gastric Cancer Cachexia Patients
We determined the therapeutic efficacy of atractylenolide I (ATR), extracted from largehead atractylodes rhizome, in managing gastric cancer cachexia (GCC), and interpreted its probable pharmacological mechanism via investigating tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6) and proteolysis-inducing factor (PIF). This was a randomized but not-blinded pilot. The study group (n = 11) received 1.32 g per day of atractylenolide I (ATR) and the control group (n = 11) received 3.6 g per day of fish-oil-enriched nutritional supplementation (FOE) for 7 weeks. Conservative therapy was similar in both groups. Clinical [appetite, body weight, mid-arm muscle circumference (MAMC), Karnofsky performance status (KPS) status], biomarker (TNF-α, IL-1, IL-6 and PIF) were evaluated in the basal state, at the third and seventh weeks. To analyze changes of cytokines, an immumohistochemistry technique was adopted. Base line characteristics were similar in both groups. Effects on MAMC and body weight increase, TNF-α increase and IL-1 decreases of serum level were significant in both groups (P < 0.05). ATR was significantly more effective than FOE in improving appetite and KPS status, and decreasing PIF positive rate (P < 0.05). Slight nausea (3/11) and dry mouth (1/11) were shown in intervention groups but did not interrupt treatment. These preliminary findings suggest that ATR might be beneficial in alleviating symptoms, in modulating cytokine and in inhibiting PIF proteolysis of gastric cancer cachexia. Further research using a randomized controlled design is necessary to confirm these pilot study findings
Age and growth of the smooth hammerhead, Sphyrna zygaena, in the Atlantic Ocean: comparison with other hammerhead species
The smooth hammerhead Sphyrna zygaena (Sphyrnidae) is a pelagic shark occasionally caught as bycatch in pelagic longline fisheries, but is one of the least studied of all pelagic sharks. Age and growth of S. zygaena was studied along a wide Atlantic region covering both the northern and southern hemispheres. Data from 304 specimens, caught between October 2009 and September 2014, ranging in size from 126 to 253 cm fork length (FL), were analysed. Growth models were fitted using the three-parameter von Bertalanffy growth function (VBGF) re-parameterized to calculate L0 (size at birth). Growth models were fitted to the sample data and data from several back-calculation models. The model fit to the quadratic modified Dahl-Lea back-calculated data seems to be the most appropriate to describe growth in this species, with resulting growth parameters of Linf = 285 cm FL, k = 0.09 year−1 for males and Linf = 293 cm FL, k = 0.09 year−1 for females. Compared with other species of the same genus, estimated growth coefficients for S. zygaena seem to fall in the low to middle range. Although further work is still needed, this study adds to knowledge of the vital life-history parameters of smooth hammerheads in the Atlantic Ocean, which can be used in the management and conservation of this species.Programa Operacional Potencial Humano: IF/00253/2014info:eu-repo/semantics/publishedVersio
Age and growth of the smooth hammerhead shark, Sphyrna zygaena, in the Eastern Equatorial Atlantic Ocean, using vertebral sections
The smooth hammerhead shark Sphyrna zygaena (Sphyrnidae) is regularly caught as bycatch in pelagic
longline fisheries, but is one of the least studied of all pelagic sharks. Recently, ICCAT (International Commission for
the Conservation of Atlantic Tunas) issued recommendations underlining the need for more studies on the life history
parameters of this and other pelagic shark species. To this end, the age and growth of S. zygaena were studied in the
Eastern Equatorial Atlantic Ocean, in an area where growth parameters were not yet available for this species. Data
from 139 specimens, caught between June and September 2009, ranging in size from 136 to 233 cm fork length (FL),
were analysed. Preliminary trials were carried out to assess the most efficient growth band enhancement technique.
These indicated that sectioning the vertebrae into 500 μm sections followed by staining with crystal violet produced
the best results. Growth models were fitted using the traditional von Bertalanffy growth equation and a modification of
this equation using a known size at birth. Growth models were compared using the Akaike information criterion (AIC).
The von Bertalanffy growth equation seemed to be the most adequate model to describe growth in this species, with
resulting growth parameters of L inf = 272 cm FL, k = 0.06 year for males and L inf = 285 cm FL, k = 0.07 year for
females. In the first four years of life, S. zygaena grows 25 cm per year on average, but its growth slows down in later
life. Future stock assessment models should incorporate these age and growth parameters for species management and
conservation.info:eu-repo/semantics/publishedVersio
Supranormal orientation selectivity of visual neurons in orientation-restricted animals
Altered sensory experience in early life often leads to remarkable adaptations so that humans and animals can make the best use of the available information in a particular environment. By restricting visual input to a limited range of orientations in young animals, this investigation shows that stimulus selectivity, e.g., the sharpness of tuning of single neurons in the primary visual cortex, is modified to match a particular environment. Specifically, neurons tuned to an experienced orientation in orientation-restricted animals show sharper orientation tuning than neurons in normal animals, whereas the opposite was true for neurons tuned to non-experienced orientations. This sharpened tuning appears to be due to elongated receptive fields. Our results demonstrate that restricted sensory experiences can sculpt the supranormal functions of single neurons tailored for a particular environment. The above findings, in addition to the minimal population response to orientations close to the experienced one, agree with the predictions of a sparse coding hypothesis in which information is represented efficiently by a small number of activated neurons. This suggests that early brain areas adopt an efficient strategy for coding information even when animals are raised in a severely limited visual environment where sensory inputs have an unnatural statistical structure
Cellular Morphology Visualization to Probe Cell Differentiation
Nuclear and cytoplasmic morphological changes provide important information about cell differentiation processes, cell functions, and signal responses. There is a strong desire to develop a rapid and simple method for visualizing cytoplasmic and nuclear morphology. Here, we developed a novel and rapid method for probing cellular morphological changes of live cell differentiation process by a fluorescent probe, TAP-4PH, a 1,3a,6a-triazapentalene derivative. TAP-4PH showed high fluorescence in cytoplasmic area, and visualized cytoplasmic and nuclear morphological changes of live cells during differentiation. We demonstrated that TAP-4PH visualized dendritic axon and spine formation in neuronal differentiation, and nuclear structural changes during neutrophilic differentiation. We also showed that the utility of TAP-4PH for visualization of cytoplasmic and nuclear morphologies of various type of live cells. Our visualizing method has no toxicity and no influence on the cellular differentiation and function. The cell morphology can be rapidly observed after addition of TAP-4PH and can continue to be observed in the presence of TAP-4PH in cell culture medium. Moreover, TAP-4PH can be easily removed after observation by washing for subsequent biological assay. Taken together, these results demonstrate that our visualization method is a powerful tool to probe differentiation processes before subsequent biological assay in live cells
Regulation of Inhibitors of Differentiation Family Proteins by Thyroid-Stimulating Hormone in FRTL-5 Thyroid Cells
Members of the inhibitors of differentiation (Id) family of helix-loop-helix (HLH) proteins are known to play important roles in the proliferation and differentiation of many cell types. Thyroid-stimulating hormone (TSH) regulates proliferation and differentiation by activating TSH receptor (TSHR) in thyrocytes. In this study, we found that Id2, one of the Id family proteins, is a major target for regulation by TSH in FRTL-5 thyroid cells. TSH rapidly increases the Id2 mRNA level in FRTL-5 thyroid cells but the Id2 protein showed biphasic regulatory patterns, being transiently reduced and subsequently induced by TSH treatment. Transient reduction of Id2 protein was noted within 2 hr of TSH treatment and was mediated by proteasomal degradation. Moreover, reduced Id2 expression correlated with the activity of the phosphatidylinositol 3 kinase pathway, which is activated by TSH. Although TSH increases the activity of the Id2 promoter, TSH-induced activation of this promoter was independent of c-Myc. Id2 did not alter TTF-1- and Pax-8-mediated effects on the regulation of the Tg promoter. Thus, in summary, we found that TSH regulates Id2 expression, but that Id2 does not alter the expression of thyroid-specific genes, such as Tg, in FRTL-5 thyroid cells
Minimal change nephrotic syndrome after stem cell transplantation: a case report and literature review
Graft-versus-host disease is one of the most frequent complications occurring after haematopoietic stem cell transplantation. Recently, renal involvement has been described as a manifestation of chronic graft-versus-host disease. Immunosuppression seems to play a major role: clinical disease is triggered by its tapering and resolution is achieved with the resumption of the immunosuppressive therapy. Prognosis is apparently favourable, but long term follow up data are lacking
- …