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2.
Eur J Case Rep Intern Med ; 11(4): 004297, 2024.
Article En | MEDLINE | ID: mdl-38584899

Chronic lymphocytic leukaemia (CLL) is a lymphoproliferative disorder characterised by an accumulation of monoclonal B lymphocytes, with an increased risk of secondary cancers. The coexistence of CLL and chronic myeloid leukaemia (CML) is a rare phenomenon, with three main types being classified: CML preceding CLL, CLL preceding CML and simultaneous occurrence. The coexistence of these chronic leukaemias poses a complex clinical challenge, with the underlying mechanisms of their association remaining enigmatic. Here, we present a report of an elderly male with a long history of CLL, who was subsequently diagnosed with secondary CML. LEARNING POINTS: The development of chronic myeloid leukaemia (CML) subsequent to chronic lymphocytic leukaemia (CLL) is an uncommon occurrence, challenging conventional expectations of disease evolution in chronic leukaemia.Extensive and appropriate testing is necessary to promptly identify secondary CML in CLL patients.Targeted therapy with dasatinib, a tyrosine kinase inhibitor, may demonstrate efficacy in reducing leukocytosis and BCR-ABL1 levels in patients with coexisting CLL and CML.

3.
Cureus ; 16(3): e56788, 2024 Mar.
Article En | MEDLINE | ID: mdl-38650771

Type B lactic acidosis, secondary to solid cancer, is very rare. It is mostly seen in patients with hematological malignancies. Although its exact pathogenesis is unknown, it is believed to be caused by overproduction and the inability of tumor cells to remove lactate. In the last 26 years, a systematic review of the literature only identified two previous reports of colorectal cancer-related type B lactic acidosis. Here, we report the third case of severe type B lactic acidosis due to stage IV colorectal with liver metastasis. Besides, this case is unique in that serum lactate levels reaching as high as 24 mmol/L were not reported in association with colorectal cancer. In most cases, the prognosis is still very poor because there are no standardized treatment recommendations. Early chemotherapy is still the only intervention that provides some survival benefits.

4.
J Neural Eng ; 21(2)2024 Apr 26.
Article En | MEDLINE | ID: mdl-38626760

Objective. In recent years, electroencephalogram (EEG)-based brain-computer interfaces (BCIs) applied to inner speech classification have gathered attention for their potential to provide a communication channel for individuals with speech disabilities. However, existing methodologies for this task fall short in achieving acceptable accuracy for real-life implementation. This paper concentrated on exploring the possibility of using inter-trial coherence (ITC) as a feature extraction technique to enhance inner speech classification accuracy in EEG-based BCIs.Approach. To address the objective, this work presents a novel methodology that employs ITC for feature extraction within a complex Morlet time-frequency representation. The study involves a dataset comprising EEG recordings of four different words for ten subjects, with three recording sessions per subject. The extracted features are then classified using k-nearest-neighbors (kNNs) and support vector machine (SVM).Main results. The average classification accuracy achieved using the proposed methodology is 56.08% for kNN and 59.55% for SVM. These results demonstrate comparable or superior performance in comparison to previous works. The exploration of inter-trial phase coherence as a feature extraction technique proves promising for enhancing accuracy in inner speech classification within EEG-based BCIs.Significance. This study contributes to the advancement of EEG-based BCIs for inner speech classification by introducing a feature extraction methodology using ITC. The obtained results, on par or superior to previous works, highlight the potential significance of this approach in improving the accuracy of BCI systems. The exploration of this technique lays the groundwork for further research toward inner speech decoding.


Brain-Computer Interfaces , Electroencephalography , Speech , Humans , Electroencephalography/methods , Electroencephalography/classification , Male , Speech/physiology , Female , Adult , Support Vector Machine , Young Adult , Reproducibility of Results , Algorithms
5.
Microbiol Resour Announc ; 12(12): e0090423, 2023 Dec 14.
Article En | MEDLINE | ID: mdl-38009928

Myxococcus xanthus is the best-studied member of the phylum Myxococcota, but the bacteriophages infecting it and their characterization remain limited. Here, we present complete genomes of Mx1, the first Myxococcus phage isolated, and of an Mx4 derivative widely used for generalized transduction, both unclassified Caudoviricetes with long, contractile tails.

6.
Life (Basel) ; 13(4)2023 Apr 17.
Article En | MEDLINE | ID: mdl-37109560

Motor neuron diseases (MNDs) are a group of chronic neurological disorders characterized by the progressive failure of the motor system. Currently, these disorders do not have a definitive treatment; therefore, it is of huge importance to propose new and more advanced diagnoses and treatment options for MNDs. Nowadays, artificial intelligence is being applied to solve several real-life problems in different areas, including healthcare. It has shown great potential to accelerate the understanding and management of many health disorders, including neurological ones. Therefore, the main objective of this work is to offer a review of the most important research that has been done on the application of artificial intelligence models for analyzing motor disorders. This review includes a general description of the most commonly used AI algorithms and their usage in MND diagnosis, prognosis, and treatment. Finally, we highlight the main issues that must be overcome to take full advantage of what AI can offer us when dealing with MNDs.

7.
Microbiol Resour Announc ; 12(3): e0102022, 2023 Mar 16.
Article En | MEDLINE | ID: mdl-36749079

Myxococcus xanthus is a social Gram-negative soil bacterium and the best studied member of the order Myxococcales in the class Deltaproteobacteria, which was recently reclassified as the phylum Myxococcota. Here, we report complete genomes, obtained using Illumina and PacBio sequencing, of M. xanthus strains DK1050 and DK101 (GenBank accession numbers CP104804 and CP104803, respectively).

8.
J Exp Biol ; 226(2)2023 01 15.
Article En | MEDLINE | ID: mdl-36576038

Haemoglobin (Hb)-O2 binding affinity typically decreases with increasing temperature, but several species of ectothermic and regionally endothermic fishes exhibit reduced Hb thermal sensitivity. Regionally endothermic sharks, including the common thresher shark (Alopias vulpinus) and lamnid sharks such as the shortfin mako shark (Isurus oxyrinchus), can maintain select tissues and organs warmer than ambient temperature by retaining metabolic heat with vascular heat exchangers. In the ectothermic bigeye thresher shark (Alopias superciliosus), diurnal movements above and below the thermocline subject the tissues, including the blood, to a wide range of operating temperatures. Therefore, blood-O2 transport must occur across internal temperature gradients in regionally endothermic species, and over the range of environmental temperatures encountered by the ectothermic bigeye thresher shark. While previous studies have shown temperature-independent Hb-O2 affinity in lamnid sharks, including shortfin mako, the Hb-O2 affinity of the common and bigeye thresher sharks is unknown. Therefore, we examined the effect of temperature on whole-blood Hb-O2 affinity in common thresher shark and bigeye thresher shark. For comparison, analyses were also conducted on the shortfin mako shark and two ectothermic species, blue shark (Prionace glauca) and spiny dogfish (Squalus acanthias). Blood-O2 binding affinity was temperature independent for common thresher shark and shortfin mako shark, which should prevent internal temperature gradients from negatively affecting blood-O2 transport. Blue shark and spiny dogfish blood-O2 affinity decreased with increasing temperature, as expected, but bigeye thresher shark blood exhibited both a reduced temperature dependence and a high Hb-O2 affinity, which likely prevents large changes in environment temperature and low environmental oxygen from affecting O2 uptake.


Sharks , Animals , Temperature , Sharks/metabolism , Oxygen/metabolism , Body Temperature Regulation , Biological Transport
9.
J Exp Biol ; 225(19)2022 10 01.
Article En | MEDLINE | ID: mdl-36124628

Smalleye Pacific opah and swordfish can conserve metabolic heat and maintain specific body regions warmer than ambient water temperature (i.e. regional heterothermy). Consequently, blood O2 uptake at the gills occurs at the environmental temperature at which the individual is found, but O2 offloading will occur at different temperatures in different tissues. While several regionally heterothermic fishes (e.g. billfishes, tunas and sharks) show a reduced temperature effect on haemoglobin (Hb)-O2 affinity, the temperature dependence of Hb-O2 affinity in opah and swordfish is unknown. We hypothesized that the Hb of opah and swordfish would also show a reduced temperature dependence. Opah whole-blood-O2 affinity exhibited a reverse temperature dependence above 50% Hb-O2 saturation (10-20°C, pH 7.2-8.0), while the temperature dependence of swordfish blood-O2 affinity (10-25°C) was saturation and pH dependent, becoming temperature independent below 50% Hb-O2 saturation and pH 7.4. Experiments on stripped haemolysates showed that adding ATP ([ATP]/[Hb]=30) decreased the temperature sensitivity of Hb-O2 affinity, changing the overall oxygenation enthalpy (ΔH') values of opah (10-20°C) and swordfish (10-25°C) Hbs at pH 7.4 from -15 and -42 kJ mol-1 O2, respectively, to +84 and -9 kJ mol-1 O2. Swordfish blood-O2 affinity was high compared with that of other large, pelagic, marine teleosts, which may be the result of unusually low ATP/Hb levels, but might also enable swordfish to forage in the potentially low-oxygenated water of the upper reaches of the oxygen minimum layer. The existence of Hbs with reduced temperature sensitivity in regionally heterothermic fishes may prevent marked changes in Hb-O2 affinity between the cold and warm tissues.


Hemoglobins , Perciformes , Adenosine Triphosphate , Animals , Fishes/metabolism , Hemoglobins/metabolism , Oxygen/metabolism , Perciformes/metabolism , Temperature , Water
10.
Front Hum Neurosci ; 16: 867281, 2022.
Article En | MEDLINE | ID: mdl-35558735

Currently, the most used method to measure brain activity under a non-invasive procedure is the electroencephalogram (EEG). This is because of its high temporal resolution, ease of use, and safety. These signals can be used under a Brain Computer Interface (BCI) framework, which can be implemented to provide a new communication channel to people that are unable to speak due to motor disabilities or other neurological diseases. Nevertheless, EEG-based BCI systems have presented challenges to be implemented in real life situations for imagined speech recognition due to the difficulty to interpret EEG signals because of their low signal-to-noise ratio (SNR). As consequence, in order to help the researcher make a wise decision when approaching this problem, we offer a review article that sums the main findings of the most relevant studies on this subject since 2009. This review focuses mainly on the pre-processing, feature extraction, and classification techniques used by several authors, as well as the target vocabulary. Furthermore, we propose ideas that may be useful for future work in order to achieve a practical application of EEG-based BCI systems toward imagined speech decoding.

13.
Microorganisms ; 9(5)2021 May 15.
Article En | MEDLINE | ID: mdl-34063365

Myxobacteria are Gram-negative δ-proteobacteria found predominantly in terrestrial habitats and often brightly colored due to the biosynthesis of carotenoids. Carotenoids are lipophilic isoprenoid pigments that protect cells from damage and death by quenching highly reactive and toxic oxidative species, like singlet oxygen, generated upon growth under light. The model myxobacterium Myxococcus xanthus turns from yellow in the dark to red upon exposure to light because of the photoinduction of carotenoid biosynthesis. How light is sensed and transduced to bring about regulated carotenogenesis in order to combat photooxidative stress has been extensively investigated in M. xanthus using genetic, biochemical and high-resolution structural methods. These studies have unearthed new paradigms in bacterial light sensing, signal transduction and gene regulation, and have led to the discovery of prototypical members of widely distributed protein families with novel functions. Major advances have been made over the last decade in elucidating the molecular mechanisms underlying the light-dependent signaling and regulation of the transcriptional response leading to carotenogenesis in M. xanthus. This review aims to provide an up-to-date overview of these findings and their significance.

14.
J Comp Physiol B ; 191(1): 127-141, 2021 01.
Article En | MEDLINE | ID: mdl-33394123

Elevated plasma potassium levels (hyperkalemia), reduced plasma pH (acidosis), reduced blood oxygen content, and elevated temperatures are associated with species-specific rates of at-vessel and post-release mortality in elasmobranch fishes. The mechanism linking these physiological disturbances to mortality remains undetermined however, and we hypothesize that the proximate cause is reduced myocardial function. We measured changes in the functional properties of isolated ventricular myocardial strips from clearnose skate (Rostroraja eglanteria), smooth dogfish (Mustelus canis), and sandbar shark (Carcharhinus plumbeus) when subjected to the following stressors (both in isolation and in combination): hyperkalemia (7.4 mM K+), acidosis (from 7.9 to 7.1), and reduced oxygen (to 31% O2 saturation) applied at temperatures 5 °C above and below holding temperatures. We selected these species based on phylogenetic distance, diverse routine activity levels, and their tolerance to capture and transport. Stressors had a few significant species-specific detrimental impacts on myocardial function (e.g., a 33-45% decrease in net force under acidosis + low O2). Net force production of myocardial strips from clearnose skate and smooth dogfish approximately doubled following exposure to isoproterenol, demonstrating that these species possess beta-adrenergic receptors and that their stimulation could provide a mechanism for preservation of cardiac function during stress. Our results suggest that disruption of physiological homeostasis associated with capture may fatally impair cardiac function in some elasmobranch species, although research with more severe stressors is needed.


Acidosis , Sharks , Skates, Fish , Animals , Dogfish , Fishes , Myocardium , Oxygen , Phylogeny , Potassium , Temperature
15.
Fish Physiol Biochem ; 46(5): 1833-1845, 2020 Oct.
Article En | MEDLINE | ID: mdl-32588156

Bigeye thresher sharks (Alopias superciliosus) and swordfish (Xiphias gladius) are large, pelagic fishes, which make long-duration, diurnal foraging dives from warm, surface waters (18-24 °C) to cold waters beneath the thermocline (5-10 °C). In bigeye thresher sharks, the subcutaneous position of the red, aerobic swimming muscles (RM) suggests that RM temperature mirrors ambient during dives (i.e., ectothermy). In swordfish, the RM is closer to the vertebrae and its associated with vascular counter-current heat exchangers that maintain RM temperature above ambient (i.e., RM endothermy). Here, we sought to determine how exposure to a wide range of ambient temperatures (8, 16, 24 °C) impacted peak power output and optimum cycle (i.e., tailbeat) frequency (0.25, 0.5, 1 Hz) in RM isolated from both species. Bigeye thresher shark RM did not produce substantial power at high cycle frequencies, even at high temperatures; but it did produce relatively high power at slow cycle frequencies regardless of temperature. Swordfish RM produced more power when operating at a combination of fast cycle frequencies and higher temperatures. This suggests that swordfish RM benefits considerably more from warming than bigeye thresher shark RM, while the RM of both species was able to produce power at cold temperatures and slow cycle frequencies. Despite different thermal strategies (i.e., ectothermy vs. RM endothermy), the ability of the RM to power sustained swimming during foraging-related search behaviors may contribute to the unique ability of these fishes to successfully exploit food resources in deep, cold water.


Fishes/anatomy & histology , Fishes/physiology , Muscle Contraction/physiology , Muscle Fibers, Slow-Twitch/physiology , Muscle, Skeletal/physiology , Temperature , Animals
16.
J Morphol ; 281(8): 938-955, 2020 08.
Article En | MEDLINE | ID: mdl-32515875

Shark skin denticles (scales) are diverse in morphology both among species and across the body of single individuals, although the function of this diversity is poorly understood. The extremely elongate and highly flexible tail of thresher sharks provides an opportunity to characterize gradients in denticle surface characteristics along the length of the tail and assess correlations between denticle morphology and tail kinematics. We measured denticle morphology on the caudal fin of three mature and two embryo common thresher sharks (Alopias vulpinus), and we compared thresher tail denticles to those of eleven other shark species. Using surface profilometry, we quantified 3D-denticle patterning and texture along the tail of threshers (27 regions in adults, and 16 regions in embryos). We report that tails of thresher embryos have a membrane that covers the denticles and reduces surface roughness. In mature thresher tails, surfaces have an average roughness of 5.6 µm which is smoother than some other pelagic shark species, but similar in roughness to blacktip, porbeagle, and bonnethead shark tails. There is no gradient down the tail in roughness for the middle or trailing edge regions and hence no correlation with kinematic amplitude or inferred magnitude of flow separation along the tail during locomotion. Along the length of the tail there is a leading-to-trailing-edge gradient with larger leading edge denticles that lack ridges (average roughness = 9.6 µm), and smaller trailing edge denticles with 5 ridges (average roughness = 5.7 µm). Thresher shark tails have many missing denticles visible as gaps in the surface, and we present evidence that these denticles are being replaced by new denticles that emerge from the skin below.


Ecosystem , Imaging, Three-Dimensional , Sharks/anatomy & histology , Tail/anatomy & histology , Animals , Biomechanical Phenomena , Dental Pulp Calcification , Discriminant Analysis , Embryo, Nonmammalian/anatomy & histology , Embryo, Nonmammalian/ultrastructure , Multivariate Analysis , Sharks/embryology , Tail/ultrastructure
17.
Nature ; 572(7770): 461-466, 2019 08.
Article En | MEDLINE | ID: mdl-31340216

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.


Animal Migration , Fisheries/statistics & numerical data , Geographic Mapping , Oceans and Seas , Sharks/physiology , Spatio-Temporal Analysis , Animals , Population Density , Risk Assessment , Sharks/classification , Ships , Time Factors
18.
J Exp Biol ; 221(Pt 19)2018 10 10.
Article En | MEDLINE | ID: mdl-30104302

We conducted in vitro inflations of freshly excised ventral aortas of the Greenland shark, Somniosus microcephalus, and used pressure-diameter data to estimate the point of transition from high to low compliance, which has been shown to occur at the mean blood pressure in other vertebrates including fishes. We also determined the pressure at which the modulus of elasticity of the aorta reached 0.4 MPa, as occurs at the compliance transition in other species. From these analyses, we predict the average ventral aortic blood pressure in S. microcephalus to be about 2.3-2.8 kPa, much lower than reported for other sharks. Our results support the idea that this species is slow moving and has a relatively low aerobic metabolism. Histological investigation of the ventral aorta shows that elastic fibres are present in relatively low abundance and loosely connected, consistent with this aorta having high compliance at a relatively low blood pressure.


Aorta/physiology , Blood Pressure , Sharks/physiology , Animals , Elasticity
19.
Nucleic Acids Res ; 46(13): 6726-6745, 2018 07 27.
Article En | MEDLINE | ID: mdl-29893914

Expression of CRISPR-Cas systems is a prerequisite for their defensive role against invading genetic elements. Yet, much remains unknown about how this crucial step is regulated. We describe a new mechanism controlling CRISPR-cas expression, which requires an extracytoplasmic function (ECF) σ factor (DdvS), its membrane-bound anti-σ (DdvA) and a global regulatory complex (CarD-CarG). Transcriptomic analyses revealed that the DdvS/CarD/CarG-dependent regulon comprises a type III-B CRISPR-Cas system in Myxococcus xanthus. We mapped four DdvS-driven CarD/CarG-dependent promoters, with one lying immediately upstream of the cas cluster. Consistent with direct action, DdvS and CarD-CarG localize at these promoters in vivo. The cas genes are transcribed as a polycistronic mRNA that reads through the leader into the CRISPR array, a putative σA-dependent promoter in the leader having negligible activity in vivo. Consequently, expression of the entire CRISPR-Cas system and mature CRISPR-RNA (crRNA) production is DdvS/CarD/CarG-dependent. DdvA likely uses its large C-terminal domain to sense and transduce the extracytoplasmic signal triggering CRISPR-cas expression, which we show is not starvation-induced multicellular development. An ECF-σ/anti-σ pair and a global regulatory complex provide an effective mechanism to coordinate signal-sensing with production of precursor crRNA, its processing Cas6 endoribonuclease and other Cas proteins for mature crRNA biogenesis and interference.


CRISPR-Associated Proteins/genetics , CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , Endoribonucleases/genetics , Gene Expression Regulation, Bacterial , Myxococcus xanthus/genetics , Sigma Factor/metabolism , Bacterial Proteins/metabolism , CRISPR-Associated Proteins/metabolism , Endoribonucleases/biosynthesis , Endoribonucleases/metabolism , Myxococcus xanthus/metabolism , Operon , Promoter Regions, Genetic , RNA, Bacterial/metabolism , Regulon , Trans-Activators/metabolism , Transcription, Genetic
20.
Fish Physiol Biochem ; 44(3): 949-967, 2018 Jun.
Article En | MEDLINE | ID: mdl-29508119

In fish, regional endothermy (i.e., the capacity to significantly elevate tissue temperatures above ambient via vascular heat exchangers) in the red swimming muscles (RM) has evolved only in a few marine groups (e.g., sharks: Lamnidae, Alopiidae, and teleosts Scombridae). Within these taxa, several species have also been shown to share similar physiological adaptations to enhance oxygen delivery to the working tissues. Although the hemoglobin (Hb) of most fish has a decreased affinity for oxygen with an increase in temperature, some regionally endothermic teleosts (e.g., tunas) have evolved Hbs that have a very low or even an increased affinity for oxygen with an increase in temperature. For sharks, however, blood oxygen affinities remain largely unknown. We examined the effects of temperature on the blood oxygen affinity in two pelagic species (the regionally endothermic shortfin mako shark and the ectothermic blue shark) at 15, 20, and 25 °C, and two coastal ectothermic species (the leopard shark and brown smooth-hound shark) at 10, 15, and 20 °C. Relative to the effects of temperature on the blood oxygen affinity of ectothermic sharks (e.g., blue shark), shortfin mako shark blood was less affected by an increase in temperature, a scenario similar to that documented in some of the tunas. In the shortfin mako shark, this may act to prevent premature oxygen dissociation from Hb as the blood is warmed during its passage through vascular heat exchangers. Even though the shortfin mako shark and blue shark occupy a similar niche, the effects of temperature on blood oxygen affinity in the latter more closely resembled that of the blood in the two coastal shark species examined in this study. The only exception was a small, reverse temperature effect (an increase in blood oxygen affinity with temperature) observed during the warming of the leopard shark blood under simulated arterial conditions, a finding that is likely related to the estuarine ecology of this species. Taken together, we found species-specific differences in how temperature affects blood oxygen affinity in sharks, with some similarities between the regionally endothermic sharks and several regionally endothermic teleost fishes.


Oxygen/blood , Sharks/blood , Temperature , Animals , Species Specificity
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