1,227 research outputs found
3-D Hand Pose Estimation from Kinect's Point Cloud Using Appearance Matching
We present a novel appearance-based approach for pose estimation of a human
hand using the point clouds provided by the low-cost Microsoft Kinect sensor.
Both the free-hand case, in which the hand is isolated from the surrounding
environment, and the hand-object case, in which the different types of
interactions are classified, have been considered. The hand-object case is
clearly the most challenging task having to deal with multiple tracks. The
approach proposed here belongs to the class of partial pose estimation where
the estimated pose in a frame is used for the initialization of the next one.
The pose estimation is obtained by applying a modified version of the Iterative
Closest Point (ICP) algorithm to synthetic models to obtain the rigid
transformation that aligns each model with respect to the input data. The
proposed framework uses a "pure" point cloud as provided by the Kinect sensor
without any other information such as RGB values or normal vector components.
For this reason, the proposed method can also be applied to data obtained from
other types of depth sensor, or RGB-D camera
Differential sensitivity of brainstem vs cortical astrocytes to changes in pH reveals functional regional specialization of astroglia
Astrocytes might function as brain interoceptors capable of detecting different (chemo)sensory modalities and transmitting sensory information to the relevant neural networks controlling vital functions. For example, astrocytes which reside near the ventral surface of the brainstem (central respiratory chemosensitive area) respond to physiological decreases in pH with vigorous elevations in intracellular Ca(2+) and release of ATP. ATP transmits astroglial excitation to the brainstem respiratory network and contributes to adaptive changes in lung ventilation. Here we show that in terms of pH-sensitivity ventral brainstem astrocytes are clearly distinct from astrocytes residing in the cerebral cortex. We monitored vesicular fusion in cultured rat brainstem astrocytes using total internal reflection fluorescence microscopy and found that approximately 35% of them respond to acidification with an increased rate of exocytosis of ATP-containing vesicular compartments. These fusion events require intracellular Ca(2+) signaling and are independent of autocrine ATP actions. In contrast, the rate of vesicular fusion in cultured cortical astrocytes is not affected by changes in pH. Compared to cortical astrocytes, ventral brainstem astrocytes display higher levels of expression of genes encoding proteins associated with ATP vesicular transport and fusion, including vesicle-associated membrane protein-3 and vesicular nucleotide transporter. These results suggest that astrocytes residing in different parts of the rat brain are functionally specialized. In contrast to cortical astrocytes, astrocytes of the brainstem chemosensitive area(s) possess signaling properties which are functionally relevant – they are able to sense changes in pH and respond to acidification with enhanced vesicular release of ATP
Screening and attraction of dust particles in plasmas.
The potential around a dust particle in a plasma is found using the collisional hydrodynamic equations of dusty plasmas, taking into account ion-dust and ion-neutral collisions and considering the plasma source proportional to the dust density. The linear screening is strongly influenced by the collisions and can substantially differ from Debye screening. Attraction of negatively charged dust particles can occur due to overscreening by the ion fluxes in the presence of friction forces
Do Patients with Bronchiectasis Have an Increased Risk of Developing Lung Cancer? A Systematic Review
Background: Initial evidence supports the hypothesis that patients with non-cystic fibrosis bronchiectasis (NCFB) have a higher risk of lung cancer. We systematically reviewed the available literature to define the characteristics of lung malignancies in patients with bronchiectasis and the characteristics of patients who develop bronchiectasis-associated lung cancer. Method: This study was performed based on the PRISMA guidelines. The review protocol was registered in PROSPERO. Results: The frequency rates of lung cancer in patients with NCFB ranged from 0.93% to 8.0%. The incidence rate was 3.96. Cancer more frequently occurred in the elderly and males. Three studies found an overall higher risk of developing lung cancer in the NCFB population compared to the non-bronchiectasis one, and adenocarcinoma was the most frequently reported histological type. The effect of the co-existence of NCFB and COPD was unclear. Conclusions: NCFB is associated with a higher risk of developing lung cancer than individuals without NCFB. This risk is higher for males, the elderly, and smokers, whereas concomitant COPD’s effect is unclear
Endoscopic Technologies for Peripheral Pulmonary Lesions: From Diagnosis to Therapy
Peripheral pulmonary lesions (PPLs) are frequent incidental findings in subjects when performing chest radiographs or chest computed tomography (CT) scans. When a PPL is identified, it is necessary to proceed with a risk stratification based on the patient profile and the characteristics found on chest CT. In order to proceed with a diagnostic procedure, the first-line examination is often a bronchoscopy with tissue sampling. Many guidance technologies have recently been developed to facilitate PPLs sampling. Through bronchoscopy, it is currently possible to ascertain the PPL’s benign or malignant nature, delaying the therapy’s second phase with radical, supportive, or palliative intent. In this review, we describe all the new tools available: from the innovation of bronchoscopic instrumentation (e.g., ultrathin bronchoscopy and robotic bronchoscopy) to the advances in navigation technology (e.g., radial-probe endobronchial ultrasound, virtual navigation, electromagnetic navigation, shape-sensing navigation, cone-beam computed tomography). In addition, we summarize all the PPLs ablation techniques currently under experimentation. Interventional pulmonology may be a discipline aiming at adopting increasingly innovative and disruptive technologies
Human biomonitoring of t-2 toxin, t-2 toxin-3-glucoside and their metabolites in urine through high-resolution mass spectrometry
The metabolic profile of T-2 toxin (T-2) and its modified form T-2-3-glucoside (T-2-3-Glc) remain unexplored in human samples. Therefore, the present study aimed to investigate the presence of T-2, T-2-3-Glc and their respective major metabolites in human urine samples (n = 300) collected in South Italy through an ultra-high performance liquid chromatography (UHPLC) coupled to Q-Orbitrap-HRMS methodology. T-2 was quantified in 21% of samples at a mean concentration of 1.34 ng/mg Crea (range: 0.22–6.54 ng/mg Crea). Almost all the major T-2 metabolites previously characterized in vitro were tentatively found, remarking the occurrence of 3′-OH-T-2 (99.7%), T-2 triol (56%) and HT-2 (30%). Regarding T-2-3-Glc, a low prevalence of the parent mycotoxin (1%) and its metabolites were observed, with HT-2-3-Glc (17%) being the most prevalent compound, although hydroxylated products were also detected. Attending to the large number of testing positive for T-2 or its metabolites, this study found a frequent exposure in Italian population
Diet-derived ergothioneine induces necroptosis in colorectal cancer cells by activating the SIRT3/MLKL pathway
SCREENING TOMATO GLUTATHIONE S-TRANSFERASE DIVERSITY FOR ASSOCIATION TO DROUGHT STRESS
Environmental stresses are one of the main challenges in agriculture, as
they significantly limit crop productivity. As a result of global warming
and climate change, extreme environmental events and abiotic stresses are
expected to increase in intensity and frequency. Selecting tolerant plants
for more resilient agro-ecosystems is a promising strategy for mitigating
the effects of adverse environments. The cultivated tomato (Solanum
lycopersicum L.) has a narrow genetic base, and its reduced genetic
diversity hampers the progress of breeding. However, the rediscovery and
use of local and wild genetic resources allow useful/beneficial alleles to
be identified and used in breeding programs. To improve adaptation to
harmful conditions, plants have evolved many molecular and genetics
mechanisms, including hormone regulation and the activation of specific
gene networks. Among others, glutathione S-transferase (GST) genes have
been identified in various plant species and found to be involved in
different physiological, developmental and stress modulation pathways. The
aim of this research is to add insights into the role of tomato GST genes
in the plant response to stress by associating allele diversity with
drought tolerance.
Tomato GST sequences were characterized in silico showing their diffuse
clustering pattern across chromosomes with TAU class GSTs duplicated in
tandem and mostly aggregated on chromosomes 7 and 9. To characterize the
diversity of selected GSTs, a core collection of 75 tomato accessions was
selected based on microsatellite screening from a larger collection of
worldwide accessions. The core collection was screened for drought
tolerance when 50% of plants showed fruit set on the lower flower truss. At
this stage, two different water treatments were applied consisting in the
complete restitution of the water lost due to evapo-transpiration (Full
Water Restitution FWR) and the restitution of 50% of the water lost (Half
Water Restitution HWR). After seven days the plants showed visible sign of
drought and the leaves were analyzed for gas exchange and colorimetric
variations. A gas exchange analyzer (Licor 6400) was used to measure the
assimilation rate of foliar CO2 (µmol CO2 m-2 s-1) and transpiration (mmol
H2O m-2 s-1). The colorimetric analysis was carried out with a portable
Chroma Meters (Minolta).
The eco-physiological data showed a continuous variability of the response
to drought throughout the collection and allowed to identify eight tomato
accessions combining a lower reduction in CO2 assimilation, transpiration
and water use efficiency and higher stability in leaf temperatures and
colorimetric variations when challenged with HWR. Enriched libraries for
GST loci were prepared based on the specific hybridization of short
oligonucleotide primers (20-25 bases). Libraries will be sequenced using
next/third generation sequencing technology (Illumina or PacBio). Mapped
variants and haplotypes in the GST loci will be integrated with drought
tolerant traits and used to identify associations with tolerant phenotypes
to additional environmental stresses
Clinical pharmacogenetics of methotrexate
It is well known that interindividual variability can affect the response to many drugs in relation to age, gender, diet, and organ function. Pharmacogenomic studies have also documented that genetic polymorphisms can exert clinically significant effects in terms of drug resistance, efficacy and toxicity by modifying the expression of critical gene products (drug-metabolizing enzymes, transporters, and target molecules) as well as pharmacokinetic and pharmacodynamic parameters. A growing body of in vitro and clinical evidence suggests that common polymorphisms in the folate gene pathway are associated with an altered response to methotrexate (MTX) in patients with malignancy and autoimmune disease. Such polymorphisms may also induce significant MTX toxicity requiring expensive monitoring and treatment. Although the available data are not conclusive, they suggest that in the future MTX pharmacogenetics could play a key role in clinical practice by improving and tailoring treatment. This review describes the genetic polymorphisms that significantly influence MTX resistance, efficacy, and toxicity
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