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Frontiers in Cellular and Infection... 2024The Asian citrus psyllid (ACP) Kuwayama is the leading vector of Liberibacter asiaticus (Las), the causative agent of citrus Huanglongbing (HLB) disease. The...
The Asian citrus psyllid (ACP) Kuwayama is the leading vector of Liberibacter asiaticus (Las), the causative agent of citrus Huanglongbing (HLB) disease. The distribution and dynamics of Las within ACP are critical to understanding how the transmission, spread and infection of Las occurs within its host vector in nature. In this study, the distribution and titer changes of Las in various tissues of ACP 5 instar nymphs and adults were examined by (FISH) and real-time quantitative PCR (qPCR) techniques. Results demonstrated that 100% of ACP 5 instar nymphs and adults were infected with Las following feeding on infected plants, and that Las had widespread distribution in most of the tissues of ACP. The titers of Las within the midgut, salivary glands and hemolymph tissues were the highest in both 5 instar nymphs and adults. When compared with adults, the titers of Las in these three tissues of 5 instar nymphs were significantly higher, while in the mycetome, ovary and testes they were significantly lower than those of adults. FISH visualization further confirmed these findings. Dynamic analysis of Las demonstrated that it was present across all the developmental ages of ACP adults. There was a discernible upward trend in the presence of Las with advancing age in most tissues of ACP adults, including the midgut, hemolymph, salivary glands, foot, head, cuticula and muscle. Our findings have significant implications for the comprehensive understanding of the transmission, dissemination and infestation of Las, which is of much importance for developing novel strategies to halt the spread of Las, and therefore contribute to the efficient prevention and control of HLB.
Topics: Animals; Hemiptera; Insect Vectors; Plant Diseases; Nymph; Citrus; In Situ Hybridization, Fluorescence; Rhizobiaceae; Real-Time Polymerase Chain Reaction; Salivary Glands; Hemolymph
PubMed: 38938879
DOI: 10.3389/fcimb.2024.1408362 -
Frontiers in Cellular and Infection... 2024Enteroaggregative (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm...
Enteroaggregative (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm formation rely on the presence of aggregative adherence fimbriae (AAF). We compared biofilm formation from two EAEC strains of each of the five AAF types. We found that AAF type did not correlate with the level of biofilm produced. Because the composition of the EAEC biofilm has not been fully described, we stained EAEC biofilms to determine if they contained protein, carbohydrate glycoproteins, and/or eDNA and found that EAEC biofilms contained all three extracellular components. Next, we assessed the changes to the growing or mature EAEC biofilm mediated by treatment with proteinase K, DNase, or a carbohydrate cleavage agent to target the different components of the matrix. Growing biofilms treated with proteinase K had decreased biofilm staining for more than half of the strains tested. In contrast, although sodium metaperiodate only altered the biofilm in a quantitative way for two strains, images of biofilms treated with sodium metaperiodate showed that the EAEC were more spread out. Overall, we found variability in the response of the EAEC strains to the treatments, with no one treatment producing a biofilm change for all strains. Finally, once formed, mature EAEC biofilms were more resistant to treatment than biofilms grown in the presence of those same treatments.
Topics: Biofilms; Endopeptidase K; Escherichia coli; Deoxyribonucleases; Fimbriae, Bacterial; Bacterial Adhesion; Humans; Periodic Acid
PubMed: 38938878
DOI: 10.3389/fcimb.2024.1379206 -
Frontiers in Neurology 2024Systemic administration of opioids has been associated with aspiration and swallow dysfunction in humans. We speculated that systemic administration of codeine would...
Systemic administration of opioids has been associated with aspiration and swallow dysfunction in humans. We speculated that systemic administration of codeine would induce dysfunctional swallowing and that this effect would have a peripheral component. Experiments were conducted in spontaneously breathing, anesthetized cats. The animals were tracheotomized and electromyogram (EMG) electrodes were placed in upper airway and chest wall respiratory muscles for recording swallow related motor activity. The animals were allocated into three groups: vagal intact (VI), cervical vagotomy (CVx), and supra-nodose ganglion vagotomy (SNGx). A dose response to intravenous codeine was performed in each animal. Swallowing was elicited by injection of 3 mL of water into the oropharynx. The number of swallows after vehicle was significantly higher in the VI group than in SNGx. Codeine had no significant effect on the number of swallows induced by water in any of the groups. However, the magnitudes of water swallow-related EMGs of the thyropharyngeus muscle were significantly increased in the VI and CVx groups by 2-4 fold in a dose-related manner. In the CVx group, the geniohyoid muscle EMG during water swallows was significantly increased. There was a significant dose-related increase in spontaneous swallowing in each group from codeine. The spontaneous swallow number at the 10 mg/kg dose of codeine was significantly larger in the CVx group than that in the SNGx group. During water-evoked swallows, intravenous codeine increased upper airway motor drive in a dose-related manner, consistent with dysregulation. The data support the existence of both central and peripheral actions of codeine on spontaneous swallowing. At the highest dose of codeine, the reduced spontaneous swallow number in the SNGx group relative to CVx is consistent with a peripheral excitatory action of codeine either on pharyngeal/laryngeal receptors or in the nodose ganglion itself. The higher number of swallows in the CVx group than the VI group supports disinhibition of this behavior by elimination of inhibitory vagal sensory afferents.
PubMed: 38938779
DOI: 10.3389/fneur.2024.1356603 -
Frontiers in Neurology 2024Real-world studies have shown the sustained therapeutic effect and favourable safety profile of OnabotulinumtoxinA (BoNTA) in the long term and up to 4 years of...
BACKGROUND
Real-world studies have shown the sustained therapeutic effect and favourable safety profile of OnabotulinumtoxinA (BoNTA) in the long term and up to 4 years of treatment in chronic migraine (CM). This study aims to assess the safety profile and efficacy of BoNTA in CM after 5 years of treatment in a real-life setting.
METHODS
We performed a retrospective chart review of patients with CM in relation to BoNTA treatment for more than 5 years in 19 Spanish headache clinics. We excluded patients who discontinued treatment due to lack of efficacy or poor tolerability.
RESULTS
489 patients were included [mean age 49, 82.8% women]. The mean age of onset of migraine was 21.8 years; patients had CM with a mean of 6.4 years (20.8% fulfilled the aura criteria). At baseline, patients reported a mean of 24.7 monthly headache days (MHDs) and 15.7 monthly migraine days (MMDs). In relation to effectiveness, the responder rate was 59.1% and the mean reduction in MMDs was 9.4 days (15.7 to 6.3 days; < 0.001). The MHDs were also reduced by 14.9 days (24.7 to 9.8 days; < 0.001). Regarding the side effects, 17.5% experienced neck pain, 17.3% headache, 8.5% eyelid ptosis, 7.5% temporal muscle atrophy and 3.2% trapezius muscle atrophy. Furthermore, after longer-term exposure exceeding 5 years, there were no serious adverse events (AE) or treatment discontinuation because of safety or tolerability issues.
CONCLUSION
Treatment with BoNTA led to sustained reductions in migraine frequency, even after long-term exposure exceeding 5 years, with no evidence of new safety concerns.
PubMed: 38938776
DOI: 10.3389/fneur.2024.1417831 -
Frontiers in Physiology 2024Although compartmentalization of the eye seems to promote its experimental manipulation, drug penetration to its posterior part is severely limited by hard barriers thus... (Review)
Review
Although compartmentalization of the eye seems to promote its experimental manipulation, drug penetration to its posterior part is severely limited by hard barriers thus hindering drug development for eye diseases. In particular, angiogenesis-related retinal diseases share common mechanisms and are responsible for the majority of cases of blindness. Their prevalence is globally increasing mostly because of the increased incidence of systemic pathologies in the adult. Despite the number of preclinical findings demonstrating the efficacy of novel treatments, therapy of retinal neovascular diseases still remains confined to intravitreal anti-vascular endothelial growth factor treatments with some extension to anti-inflammatory therapy. In the of preclinical findings aimed to develop novel avenues for future therapies, most compounds, despite their efficacy in experimental models, do not seem to meet the criteria for their therapeutic application. In particular, the groove between preclinical findings and their clinical application increases instead of decreasing and the attempt to bridging the gap between them creates intense frustration and a sense of defeat. In this complex scenario, we will discuss here the role that overactivation of the sympathetic system plays in retinal vessel proliferation in response to hypoxia using the oxygen-induced retinopathy (OIR) model. The potential application of the beta-adrenoceptor (β-AR) blockade with propranolol to the treatment of retinopathy of prematurity will be also discussed in light of preclinical findings in the OIR model and clinical trials using propranolol in preterm infants either or as eye drops.
PubMed: 38938747
DOI: 10.3389/fphys.2024.1408605 -
Frontiers in Cardiovascular Medicine 2024Vascular pathologies are prevalent in a broad spectrum of diseases, necessitating a deeper understanding of vascular biology, particularly in overcoming the oxygen and... (Review)
Review
Vascular pathologies are prevalent in a broad spectrum of diseases, necessitating a deeper understanding of vascular biology, particularly in overcoming the oxygen and nutrient diffusion limit in tissue constructs. The evolution of vascularized tissues signifies a convergence of multiple scientific disciplines, encompassing the differentiation of human pluripotent stem cells (hPSCs) into vascular cells, the development of advanced three-dimensional (3D) bioprinting techniques, and the refinement of bioinks. These technologies are instrumental in creating intricate vascular networks essential for tissue viability, especially in thick, complex constructs. This review provides broad perspectives on the past, current state, and advancements in key areas, including the differentiation of hPSCs into specific vascular lineages, the potential and challenges of 3D bioprinting methods, and the role of innovative bioinks mimicking the native extracellular matrix. We also explore the integration of biophysical cues in vascularized tissues , highlighting their importance in stimulating vessel maturation and functionality. In this review, we aim to synthesize these diverse yet interconnected domains, offering a broad, multidisciplinary perspective on tissue vascularization. Advancements in this field will help address the global organ shortage and transform patient care.
PubMed: 38938652
DOI: 10.3389/fcvm.2024.1336910 -
Frontiers in Cardiovascular Medicine 2024During donation after circulatory death (DCD), cardiac grafts are exposed to potentially damaging conditions that can impact their quality and post-transplantation...
BACKGROUND
During donation after circulatory death (DCD), cardiac grafts are exposed to potentially damaging conditions that can impact their quality and post-transplantation outcomes. In a clinical DCD setting, patients have closed chests in most cases, while many experimental models have used open-chest conditions. We therefore aimed to investigate and characterize differences in open- vs. closed-chest porcine models.
METHODS
Withdrawal of life-sustaining therapy (WLST) was simulated in anesthetized juvenile male pigs by stopping mechanical ventilation following the administration of a neuromuscular block. Functional warm ischemic time (fWIT) was defined to start when systolic arterial pressure was <50 mmHg. Hemodynamic changes and blood chemistry were analyzed. Two experimental groups were compared: (i) an open-chest group with sternotomy prior to WLST and (ii) a closed-chest group with sternotomy after fWIT.
RESULTS
Hemodynamic changes during the progression from WLST to fWIT were initiated by a rapid decline in blood oxygen saturation and a subsequent cardiovascular hyperdynamic (HD) period characterized by temporary elevations in heart rates and arterial pressures in both groups. Subsequently, heart rate and systolic arterial pressure decreased until fWIT was reached. Pigs in the open-chest group displayed a more rapid transition to the HD phase after WLST, with peak heart rate and peak rate-pressure product occurring significantly earlier. Furthermore, the HD phase duration tended to be shorter and less intense (lower peak rate-pressure product) in the open-chest group than in the closed-chest group.
DISCUSSION
Progression from WLST to fWIT was more rapid, and the hemodynamic changes tended to be less pronounced in the open-chest group than in the closed-chest group. Our findings support clear differences between open- and closed-chest models of DCD. Therefore, recommendations for clinical DCD protocols based on findings in open-chest models must be interpreted with care.
PubMed: 38938649
DOI: 10.3389/fcvm.2024.1325160 -
Frontiers in Plant Science 2024
PubMed: 38938634
DOI: 10.3389/fpls.2024.1428049 -
Frontiers in Plant Science 2024To maximise the throughput of novel, high-throughput phenotyping platforms, many researchers have utilised smaller pot sizes to increase the number of biological...
To maximise the throughput of novel, high-throughput phenotyping platforms, many researchers have utilised smaller pot sizes to increase the number of biological replicates that can be grown in spatially limited controlled environments. This may confound plant development through a process known as "pot binding", particularly in larger species including potato (), and under water-restricted conditions. We aimed to investigate the water availability hypothesis of pot binding, which predicts that small pots have insufficient water holding capacities to prevent drought stress between irrigation periods, in potato. Two cultivars of potato were grown in small (5 L) and large (20 L) pots, were kept under polytunnel conditions, and were subjected to three irrigation frequencies: every other day, daily, and twice daily. Plants were phenotyped with two Phenospex PlantEye F500s and canopy and tuber fresh mass and dry matter were measured. Increasing irrigation frequency from every other day to daily was associated with a significant increase in fresh tuber yield, but only in large pots. This suggests a similar level of drought stress occurred between these treatments in the small pots, supporting the water availability hypothesis of pot binding. Further increasing irrigation frequency to twice daily was still not sufficient to increase yields in small pots but it caused an insignificant increase in yield in the larger pots, suggesting some pot binding may be occurring in large pots under daily irrigation. Canopy temperatures were significantly higher under each irrigation frequency in the small pots compared to large pots, which strongly supports the water availability hypothesis as higher canopy temperatures are a reliable indicator of drought stress in potato. Digital phenotyping was found to be less accurate for larger plants, probably due to a higher degree of self-shading. The research demonstrates the need to define the optimum pot size and irrigation protocols required to completely prevent pot binding and ensure drought treatments are not inadvertently applied to control plants.
PubMed: 38938631
DOI: 10.3389/fpls.2024.1399250 -
Frontiers in Plant Science 2024
PubMed: 38938630
DOI: 10.3389/fpls.2024.1439668