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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32814014

RESUMEN

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Asunto(s)
Variación Genética/genética , Enfermedades por Picaduras de Garrapatas/microbiología , Garrapatas/genética , Animales , Línea Celular , Vectores de Enfermedades , Especificidad del Huésped/genética
2.
J Virol ; 98(2): e0180123, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38193691

RESUMEN

In mammals, NLRX1 is a unique member of the nucleotide-binding domain and leucine-rich repeat (NLR) family showing an ability to negatively regulate IFN antiviral immunity. Intron-containing genes, including NLRX1, have more than one transcript due to alternative splicing; however, little is known about the function of its splicing variants. Here, we identified a transcript variant of NLRX1 in zebrafish (Danio rerio), termed NLRX1-tv4, as a negative regulator of fish IFN response. Zebrafish NLRX1-tv4 was slightly induced by viral infection, with an expression pattern similar to the full-length NLRX1. Despite the lack of an N-terminal domain that exists in the full-length NLRX1, overexpression of NLRX1-tv4 still impaired fish IFN antiviral response and promoted viral replication in fish cells, similar to the full-length NLRX1. Mechanistically, NLRX1-tv4 targeted STING for proteasome-dependent protein degradation by recruiting an E3 ubiquitin ligase RNF5 to drive the K48-linked ubiquitination, eventually downregulating the IFN antiviral response. Mapping of NLRX1-tv4 domains showed that its N-terminal and C-terminal regions exhibited a similar potential to inhibit STING-mediated IFN antiviral response. Our findings reveal that like the full-length NLRX1, zebrafish NLRX-tv4 functions as an inhibitor to shape fish IFN antiviral response.IMPORTANCEIn this study, we demonstrate that a transcript variant of zebrafish NLRX1, termed NLRX1-tv4, downregulates fish IFN response and promotes virus replication by targeting STING for protein degradation and impairing the interaction of STING and TBK1 and that its N- and C-terminus exhibit a similar inhibitory potential. Our results are helpful in clarifying the current contradictory understanding of structure and function of vertebrate NLRX1s.


Asunto(s)
Proteínas de la Membrana , Proteínas Mitocondriales , Proteínas de Pez Cebra , Animales , Inmunidad Innata , Dominios Proteicos , Isoformas de Proteínas/genética , Ubiquitina-Proteína Ligasas , Ubiquitinación , Pez Cebra/inmunología , Pez Cebra/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas de Pez Cebra/metabolismo , Proteínas de la Membrana/metabolismo , Interferones/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(25): e2026733119, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35709320

RESUMEN

Safeguarding Earth's tree diversity is a conservation priority due to the importance of trees for biodiversity and ecosystem functions and services such as carbon sequestration. Here, we improve the foundation for effective conservation of global tree diversity by analyzing a recently developed database of tree species covering 46,752 species. We quantify range protection and anthropogenic pressures for each species and develop conservation priorities across taxonomic, phylogenetic, and functional diversity dimensions. We also assess the effectiveness of several influential proposed conservation prioritization frameworks to protect the top 17% and top 50% of tree priority areas. We find that an average of 50.2% of a tree species' range occurs in 110-km grid cells without any protected areas (PAs), with 6,377 small-range tree species fully unprotected, and that 83% of tree species experience nonnegligible human pressure across their range on average. Protecting high-priority areas for the top 17% and 50% priority thresholds would increase the average protected proportion of each tree species' range to 65.5% and 82.6%, respectively, leaving many fewer species (2,151 and 2,010) completely unprotected. The priority areas identified for trees match well to the Global 200 Ecoregions framework, revealing that priority areas for trees would in large part also optimize protection for terrestrial biodiversity overall. Based on range estimates for >46,000 tree species, our findings show that a large proportion of tree species receive limited protection by current PAs and are under substantial human pressure. Improved protection of biodiversity overall would also strongly benefit global tree diversity.


Asunto(s)
Efectos Antropogénicos , Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Árboles , Conservación de los Recursos Naturales/métodos , Humanos , Filogenia , Árboles/clasificación
4.
Ecol Lett ; 27(6): e14446, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38814284

RESUMEN

Grime's competitive, stress-tolerant, ruderal (CSR) theory predicts a shift in plant communities from ruderal to stress-tolerant strategies during secondary succession. However, this fundamental tenet lacks empirical validation using long-term continuous successional data. Utilizing a 60-year longitudinal data of old-field succession, we investigated the community-level dynamics of plant strategies over time. Our findings reveal that while plant communities generally transitioned from ruderal to stress-tolerant strategies during succession, initial abandonment conditions crucially shaped early successional strategies, leading to varied strategy trajectories across different fields. Furthermore, we found a notable divergence in the CSR strategies of alien and native species over succession. Initially, alien and native species exhibited similar ruderal strategies, but in later stages, alien species exhibited higher ruderal and lower stress tolerance compared to native species. Overall, our findings underscore the applicability of Grime's predictions regarding temporal shifts in CSR strategies depending on both initial community conditions and species origin.


Asunto(s)
Especies Introducidas , Plantas , Fenómenos Fisiológicos de las Plantas , Estrés Fisiológico , Ecosistema , Modelos Biológicos , Desarrollo de la Planta
5.
EMBO J ; 39(10): e103111, 2020 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-32187724

RESUMEN

The homeostatic link between oxidative stress and autophagy plays an important role in cellular responses to a wide variety of physiological and pathological conditions. However, the regulatory pathway and outcomes remain incompletely understood. Here, we show that reactive oxygen species (ROS) function as signaling molecules that regulate autophagy through ataxia-telangiectasia mutated (ATM) and cell cycle checkpoint kinase 2 (CHK2), a DNA damage response (DDR) pathway activated during metabolic and hypoxic stress. We report that CHK2 binds to and phosphorylates Beclin 1 at Ser90/Ser93, thereby impairing Beclin 1-Bcl-2 autophagy-regulatory complex formation in a ROS-dependent fashion. We further demonstrate that CHK2-mediated autophagy has an unexpected role in reducing ROS levels via the removal of damaged mitochondria, which is required for cell survival under stress conditions. Finally, CHK2-/- mice display aggravated infarct phenotypes and reduced Beclin 1 p-Ser90/Ser93 in a cerebral stroke model, suggesting an in vivo role of CHK2-induced autophagy in cell survival. Taken together, these results indicate that the ROS-ATM-CHK2-Beclin 1-autophagy axis serves as a physiological adaptation pathway that protects cells exposed to pathological conditions from stress-induced tissue damage.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Beclina-1/metabolismo , Quinasa de Punto de Control 2/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Autofagia , Línea Celular , Modelos Animales de Enfermedad , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Ratones , Estrés Oxidativo , Fosforilación
6.
J Urol ; : 101097JU0000000000004129, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950376

RESUMEN

PURPOSE: Nocturnal urine volume and bladder reservoir function are key pathogenic factors behind monosymptomatic nocturnal enuresis (MNE). We investigated the predictive value of these together with other demographic and clinical variables for response to first-line treatments in children with MNE. MATERIALS AND METHODS: A randomized, controlled, international multicenter study was conducted in 324 treatment-naïve children (6-14 years) with primary MNE. The children were randomized to treatment with or without prior consideration of voiding diaries. In the group where treatment choice was based on voiding diaries, children with nocturnal polyuria and normal maximum voided volume (MVV) received desmopressin (dDAVP) treatment and children with reduced MVV and no nocturnal polyuria received an enuresis alarm. In the other group, treatment with dDAVP or alarm was randomly allocated. RESULTS: A total of 281 children (72% males) were qualified for statistical analysis. The change of responding to treatment was 21% higher in children where treatment was individualized compared to children where treatment was randomly selected (RR = 1.21 (1.02-1.45), P = .032). In children with reduced MVV and no nocturnal polyuria (35% of all children), individualized treatment was associated with a 46% improvement in response compared to random treatment selection (RR = 1.46 (1.14-1.87), P = .003). Furthermore, we developed a clinically relevant prediction model for response to dDAVP treatment (ROC 0.85). CONCLUSIONS: The present study demonstrates that treatment selection based on voiding diaries improve response to first line treatment, particularly in specific subtypes. Information from voiding diaries together with clinical and demographic information provides the basis for predicting response.

7.
J Med Virol ; 96(2): e29433, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38293900

RESUMEN

High-risk populations are the predominant populations affected by hepatitis C virus (HCV) infection, and there is an urgent need for efficient and cost-effective HCV testing strategies for high-risk populations to identify potential undiagnosed HCV-infected individuals. This study compared several commonly used testing strategies and conducted effectiveness and cost analysis to select the appropriate testing strategy for diagnosing HCV infection in high-risk populations. Among the 2093 samples from high-risk populations in this study, 1716 were HCV negative, 237 were current HCV infection, 137 were past HCV infection, and three were acute early HCV infection. It was found that out of 237 patients with HCV current infection, Strategy A could detect 225 cases, with a missed detection rate of 5.06%, and the total cost was 33 299 RMB. In addition, Strategy B could detect 237 cases of current HCV infection, and the HCV missed detection rate was 0.00%, and the total cost was 147 221 RMB. While 137 cases of past HCV infection could be distinguished by strategy C, but 14 cases with current HCV infection were missed, with an HCV-positive missed detection rate of 5.91%, and the total cost for Strategy C was 43 059 RMB. In conclusion, in high-risk populations, the HCV positivity rate is typically higher. If feasible, the preferred approach is to directly conduct HCV RNA testing, which effectively minimizes the risk of missing cases. However, in situations with limited resources, it is advisable to initially choose a highly sensitive method for anti-HCV screening, followed by HCV RNA testing on reactive samples.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Hepacivirus/genética , Análisis Costo-Beneficio , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Factores de Riesgo , ARN
8.
Plant Physiol ; 193(1): 448-465, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37217835

RESUMEN

Bud dormancy is crucial for winter survival and is characterized by the inability of the bud meristem to respond to growth-promotive signals before the chilling requirement (CR) is met. However, our understanding of the genetic mechanism regulating CR and bud dormancy remains limited. This study identified PpDAM6 (DORMANCY-ASSOCIATED MADS-box) as a key gene for CR using a genome-wide association study analysis based on structural variations in 345 peach (Prunus persica (L.) Batsch) accessions. The function of PpDAM6 in CR regulation was demonstrated by transiently silencing the gene in peach buds and stably overexpressing the gene in transgenic apple (Malus × domestica) plants. The results showed an evolutionarily conserved function of PpDAM6 in regulating bud dormancy release, followed by vegetative growth and flowering, in peach and apple. The 30-bp deletion in the PpDAM6 promoter was substantially associated with reducing PpDAM6 expression in low-CR accessions. A PCR marker based on the 30-bp indel was developed to distinguish peach plants with non-low and low CR. Modification of the H3K27me3 marker at the PpDAM6 locus showed no apparent change across the dormancy process in low- and non-low- CR cultivars. Additionally, H3K27me3 modification occurred earlier in low-CR cultivars on a genome-wide scale. PpDAM6 could mediate cell-cell communication by inducing the expression of the downstream genes PpNCED1 (9-cis-epoxycarotenoid dioxygenase 1), encoding a key enzyme for ABA biosynthesis, and CALS (CALLOSE SYNTHASE), encoding callose synthase. We shed light on a gene regulatory network formed by PpDAM6-containing complexes that mediate CR underlying dormancy and bud break in peach. A better understanding of the genetic basis for natural variations of CR can help breeders develop cultivars with different CR for growing in different geographical regions.


Asunto(s)
Malus , Prunus persica , Prunus , Prunus persica/genética , Prunus persica/metabolismo , Prunus/genética , Prunus/metabolismo , Histonas/metabolismo , Estudio de Asociación del Genoma Completo , Malus/genética , Regulación de la Expresión Génica de las Plantas , Latencia en las Plantas/genética
9.
Plant Physiol ; 192(4): 2838-2854, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37204807

RESUMEN

Somatic embryogenesis (SE) is a key regeneration pathway in various biotechnology approaches to crop improvement, especially for economically important perennial woody crops like citrus. However, maintenance of SE capability has long been a challenge and becomes a bottleneck in biotechnology-facilitated plant improvement. In the embryogenic callus (EC) of citrus, we identified 2 csi-miR171c-targeted SCARECROW-LIKE genes CsSCL2 and CsSCL3 (CsSCL2/3), which exert positive feedback regulation on csi-miR171c expression. Suppression of CsSCL2 expression by RNA interference (RNAi) enhanced SE in citrus callus. A thioredoxin superfamily protein CsClot was identified as an interactive protein of CsSCL2/3. Overexpression of CsClot disturbed reactive oxygen species (ROS) homeostasis in EC and enhanced SE. Chromatin immunoprecipitation sequencing (ChIP-Seq) and RNA-Seq identified 660 genes directly suppressed by CsSCL2 that were enriched in biological processes including development-related processes, auxin signaling pathway, and cell wall organization. CsSCL2/3 bound to the promoters of regeneration-related genes, such as WUSCHEL-RELATED HOMEOBOX 2 (CsWOX2), CsWOX13, and Lateral Organ Boundaries Domain 40 (LBD40), and repressed their expression. Overall, CsSCL2/3 modulate ROS homeostasis through the interactive protein CsClot and directly suppress the expression of regeneration-related genes, thus regulating SE in citrus. We uncovered a regulatory pathway of miR171c-targeted CsSCL2/3 in SE, which shed light on the mechanism of SE and regeneration capability maintenance in citrus.


Asunto(s)
Citrus , Citrus/genética , Citrus/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Biotecnología , RNA-Seq , Regeneración , Técnicas de Embriogénesis Somática de Plantas , Regulación de la Expresión Génica de las Plantas
10.
Opt Express ; 32(11): 20119-20127, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859128

RESUMEN

Generating multiple beams in distinct polarization states is promising in multi-mode wireless communication but still remains challenging in metasurface design. Here, we theoretically and experimentally demonstrate a concept of broadband receiving-transmitting metasurface and its application to the generation of multi-polarization multi-beam. By employing U-slot patch, an efficient receiving-transmitting element with full phase coverage is designed within a wide bandwidth. Based on this architecture, a methodology is proposed to generate dual spin-decoupled beams and then developed into the strategy of generating multiple beams at different linear polarizations. To verify our strategy, two lens antennas, respectively radiating dual-spin dual-beam and quad-polarization quad-beam, are devised. With multi-polarization multi-beam radiated, the two lens antennas are both with whole aperture efficiency above 40% within the bandwidth of 10.6-12.3 GHz (14.8%), firmly validating our strategy and design.

11.
FASEB J ; 37(10): e23205, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37768886

RESUMEN

Brain aging is the most important risk factor for neurodegenerative disorders, and abnormal apoptosis is linked to neuronal dysfunction. Specifically, studies have found that exercise effectively inhibits hippocampal neuronal apoptosis, while the molecular mechanism remains unclear. In the present study, we investigated the impact of aerobic exercise on hippocampal neuronal apoptosis in aging mice and the potential involvement of DAPK1 and its downstream pathways based on recent data that DAPK1 may be associated with neuronal death in neurodegenerative diseases. Senescent mice were subjected to 8 weeks of Aerobic training. Following behavioral testing, hippocampal samples were examined histologically and biochemically to detect pathological changes, neuronal apoptosis, and mRNA and protein levels. We found that the exercise intervention improved spatial memory and alleviated neuronal apoptosis in the brain. Notably, exercise down-regulated DAPK1 expression and inhibited Fas death receptor transactivation and the mitochondrial apoptotic pathway in the hippocampus. These results shed new light on the protective effect of regular exercise against brain aging though modulating the DAPK1 pathway.


Asunto(s)
Galactosa , Enfermedades Neurodegenerativas , Ratones , Animales , Galactosa/metabolismo , Galactosa/farmacología , Apoptosis , Hipocampo/metabolismo , Envejecimiento , Enfermedades Neurodegenerativas/metabolismo , Transducción de Señal
12.
Neurochem Res ; 49(4): 1105-1120, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38289520

RESUMEN

Reduced myelin stability observed in the early stages of Alzheimer's disease leads to spatial learning and memory impairment. Exercise has been shown to protect nerves, reduce the risk of Alzheimer's disease, and strengthen synaptic connectivity. However, the underlying mechanisms of how exercise can promote myelin repair and coordinate inflammation and proliferation are still uncertain. In this study, we conducted histological and biochemical assays of cortical lysates after behavioral testing to detect pathological changes, myelin sheath thickness, and mRNA and protein levels. It is notable that D-galactose model mice exhibited elevated miRNA-34a levels, overactive astrocytes, decreased myelin staining scores, increased apoptosis, and decreased synaptic plasticity in the brain. Significantly, after eight weeks of exercise, we observed improvements in LFB scores, NeuN( +) neuron counts, and myelin basic protein (MBP) expression. Additionally, exercise promoted the expression of oligodendrocyte markers Olig2 and PDFGR-α associated with brain proliferation, and improved spatial cognitive function. Furthermore, it decreased the inflammation caused by astrocyte secretions (TNF-α, Cox-2, CXCL2). Interestingly, we also observed downregulation of miR-34a and activation of the TAN1/PI3K/CREB signaling pathway. Our data shed light on a previously unsuspected mechanism by which exercise reduces miR-34a levels and protects neuronal function and survival by preventing excessive demyelination and inflammatory infiltration in the CNS.


Asunto(s)
Enfermedad de Alzheimer , MicroARNs , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Astrocitos/metabolismo , Inflamación/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Vaina de Mielina/metabolismo , Enfermedades Neuroinflamatorias , Oligodendroglía/metabolismo
13.
Langmuir ; 40(1): 282-290, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38131624

RESUMEN

Polymeric zwitterions exhibit exceptional fouling resistance through the formation of a strongly hydrated surface of immobilized water molecules. While being extensively tested for their performance in biomedical, membrane, and, to a lesser extent, marine environments, few studies have investigated how the molecular design of the zwitterion may enhance its performance. Furthermore, while theories of zwitterion antifouling mechanisms exist for molecular-scale foulant species (e.g., proteins and small molecules), it remains unclear how molecular-scale mechanisms influence the micro- and macroscopic interactions of relevance for marine applications. The present study addresses these gaps through the use of a modular zwitterion chemistry platform, which is characterized by a combination of surface-sensitive sum frequency generation (SFG) vibrational spectroscopy and marine assays. Zwitterions with increasingly delocalized cations demonstrate improved fouling resistance against the green alga Ulva linza. SFG spectra correlate well with the assay results, suggesting that the more diffuse charges exhibit greater surface hydration with more bound water molecules. Hence, the number of bound interfacial water molecules appears to be more influential in determining the marine antifouling activities of zwitterionic polymers than the binding strength of individual water molecules at the interface.

14.
J Pharmacol Sci ; 154(4): 236-245, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38485341

RESUMEN

Postpartum depression (PPD) is a significant contributor to maternal morbidity and mortality. The Sigma-1 (σ-1) receptor has received increasing attention in recent years because of its ability to link different signaling systems and exert its function in the brain through chaperone actions, especially in neuropsychiatric disorders. YL-0919, a novel σ-1 receptor agonist developed by our institute, has shown antidepressive and anxiolytic effects in a variety of animal models, but effects on PPD have not been revealed. In the present study, excitatory/inhibitory signaling in the hippocampus was reflected by GABA and glutamate and their associated excitatory-inhibitory receptor proteins, the HPA axis hormones in the hippocampus were assessed by ELISA. Finally, immunofluorescence for markers of newborn neuron were undertaken in the dentate gyri, along with dendritic spine staining and dendritic arborization tracing. YL-0919 rapidly improves anxiety and depressive-like behavior in PPD-like mice within one week, along with normalizing the excitation/inhibition signaling as well as the HPA axis activity. YL-0919 rescued the decrease in hippocampal dendritic complexity and spine density induced by estrogen withdrawal. The study results suggest that YL-0919 elicits a therapeutic effect on PPD-like mice; therefore, the σ-1 receptor may be a novel promising target for PPD treatment in the future.


Asunto(s)
Ácido Glutámico , Receptor Sigma-1 , Femenino , Ratones , Animales , Ácido Glutámico/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Hipocampo/metabolismo , Ansiedad/tratamiento farmacológico , Ansiedad/metabolismo , Estrógenos , Plasticidad Neuronal , Ácido gamma-Aminobutírico/metabolismo
15.
Phys Chem Chem Phys ; 26(24): 17075-17082, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38842020

RESUMEN

The topological and magnetic properties induced by topological defects in graphene have attracted attention. Here, we study a novel topological defect structure for graphene nanoribbons interspersed with C558-line defects along the armchair boundary, which possesses topological properties and is tritopic. Using strain engineering to regulate the magnitude of hopping at defects, the position of the energy level can be easily changed to achieve a topological phase transition. We also discuss the local magnetic moment and the ferromagnetic ground state in the context of line defects. This leads to spin polarization of the whole system. Finally, when C558 graphene nanoribbons are controlled by a nonlocal exchange magnetic field, spin-polarized quantum conductivity occurs near the Fermi level. Consequently, spin filtering can be achieved by varying the incident energy of the electrons. Our results provide new insights into realizing topological and spin electronics in low-dimensional quantum devices.

16.
J Appl Microbiol ; 135(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38925653

RESUMEN

AIMS: This study aimed to assess the pharmacokinetic/pharmacodynamic (PK/PD) targets of danofloxacin to minimize the risk of selecting resistant Pasteurella multocida mutants and to identify the mechanisms underlying their resistance in an in vitro dynamic model, attaining the optimum dosing regimen of danofloxacin to improve its clinical efficacy based on the mutant selection window (MSW) hypothesis. METHODS AND RESULTS: Danofloxacin at seven dosing regimens and 5 days of treatment were simulated to quantify the bactericidal kinetics and enrichment of resistant mutants upon continuous antibiotic exposure. The magnitudes of PK/PD targets associated with different efficacies were determined in the model. The 24 h area under the concentration-time curve (AUC) to minimum inhibitory concentration (MIC) ratios (AUC24h/MIC) of danofloxacin associated with bacteriostatic, bactericidal and eradication effects against P. multocida were 34, 52, and 64 h. This translates to average danofloxacin concentrations (Cav) over 24 h being 1.42, 2.17, and 2.67 times the MIC, respectively. An AUC/MIC-dependent antibacterial efficacy and AUC/mutant prevention concentration (MPC)-dependent enrichment of P. multocida mutants in which maximum losses in danofloxacin susceptibility occurred at a simulated AUC24h/MIC ratio of 72 h (i.e. Cav of three times the MIC). The overexpression of efflux pumps (acrAB-tolC) and their regulatory genes (marA, soxS, and ramA) was associated with reduced susceptibility in danofloxacin-exposed P. multocida. The AUC24h/MPC ratio of 19 h (i.e. Cav of 0.8 times the MPC) was determined to be the minimum mutant prevention target value for the selection of resistant P. multocida mutants. CONCLUSIONS: The emergence of P. multocida resistance to danofloxacin exhibited a concentration-dependent pattern and was consistent with the MSW hypothesis. The current clinical dosing regimen of danofloxacin (2.5 mg kg-1) may have a risk of treatment failure due to inducible fluoroquinolone resistance.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Fluoroquinolonas , Pruebas de Sensibilidad Microbiana , Pasteurella multocida , Pasteurella multocida/efectos de los fármacos , Pasteurella multocida/genética , Fluoroquinolonas/farmacología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Mutación
17.
J Ultrasound Med ; 43(1): 21-31, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37772628

RESUMEN

OBJECTIVES: This study aimed to investigate the combined use of ultrasonography and clinical features for the differentiation of malignant peripheral nerve sheath tumors (MPNST) from benign peripheral nerve sheath tumors (BPNST) and to compare the efficacy of ultrasonography with that of magnetic resonance imaging (MRI). METHODS: This retrospective study included 28 MPNSTs and a control group of 57 BPNSTs. All patients underwent an ultrasound scan using the Logiq E9 (GE Health Care, Milwaukee, WI) or EPIQ7 equipment (Philips Medical System, Bothell, WA). A 3.0-T MRI machine (Ingenia; Philips Healthcare, Best, the Netherlands) was used for scanning, and conventional MRI was performed on different regions based on the patient's clinical situation. The following variables were evaluated: palpable mass, pain, nerve symptoms, maximum diameter, location, shape, boundary, encapsulation, echogenicity, echo homogeneity, presence of a cystic component, calcification, target sign, posterior echo, and intertumoral vascularity of the tumors. The diagnostic efficacy of ultrasonography and clinical factors was compared with that of MRI. Independent factors for predicting MPNST versus BPNST were also assessed. RESULTS: The parameters of location, shape, boundary, encapsulation, and vascularity were significantly different between MPNSTs and BPNSTs. Multiple logistic regression analysis showed that shape, boundary, and vascularity were independent predictors of MPNSTs. The sensitivity, specificity, and Youden index of the three clinical and ultrasound factors (shape, boundary, and vascularity) were 0.89, 0.81, and 0.69, respectively, whereas those of MRI were 0.71, 0.89, and 0.61, respectively. No significant differences in the area under the curve (AUC) of the three combined clinical and ultrasound factors and those of MRI were found (P > .05). CONCLUSIONS: MRI was useful in the differential diagnosis between MPNSTs and BPNSTs. However, the combination of clinical and ultrasound diagnoses can achieve the same effect as MRI, including shape, boundary, and vasculature.


Asunto(s)
Neoplasias de la Vaina del Nervio , Neurofibrosarcoma , Humanos , Estudios Retrospectivos , Neoplasias de la Vaina del Nervio/diagnóstico por imagen , Neoplasias de la Vaina del Nervio/patología , Imagen por Resonancia Magnética/métodos , Ultrasonografía
18.
J Dairy Sci ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38642661

RESUMEN

Spermatogenesis is a continuous process in which functional sperm are produced through a series of mitotic and meiotic divisions and morphological changes in germ cells. The aberrant development and fate transitions of spermatogenic cells cause hybrid sterility in mammals. Cattle-yak, a hybrid animal between taurine cattle (Bos taurus) and yak (Bos grunniens), exhibits male-specific sterility due to spermatogenic failure. In the present study, we performed single-cell RNA sequencing analysis to identify differences in testicular cell composition and the developmental trajectory of spermatogenic cells between yak and cattle-yak. The composition and molecular signatures of spermatogonial subtypes were dramatically different between these 2 animals, and the expression of genes associated with stem cell maintenance, cell differentiation and meiotic entry was altered in cattle-yak, indicating the impairment of undifferentiated spermatogonial fate decisions. Cell communication analysis revealed that signaling within different spermatogenic cell subpopulations was weakened, and progenitor spermatogonia were unable or delayed receiving and sending signals for transformation to the next stage in cattle-yak. Simultaneously, the communication between niche cells and germ cells was also abnormal. Collectively, we obtained the expression profiles of transcriptome signatures of different germ cells and testicular somatic cell populations at the single-cell level and identified critical regulators of spermatogonial differentiation and meiosis in yak and sterile cattle-yak. The findings of this study shed light on the genetic mechanisms that lead to hybrid sterility and speciation in bovid species.

19.
Neurocrit Care ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561586

RESUMEN

BACKGROUND: We aimed to investigate the associations of macrophage migration inhibitory factor (MIF), toll-like receptors 2 and 4 (TLR2/4), and matrix metalloproteinase 9 (MMP9) with 3-month poor outcome, death, and malignant cerebral edema (MCE) in patients with large hemispheric infarction (LHI). METHODS: Patients with LHI within 24 h of onset were enrolled consecutively. Serum MIF, TLR2/4, and MMP9 concentrations on admission were measured. Poor outcome was defined as a modified Rankin Scale score of ≥ 3 at 3 months. MCE was defined as a decreased level of consciousness, anisocoria and midline shift > 5 mm or basal cistern effacement, or indications for decompressive craniectomy during hospitalization. The cutoff values for MIF/MMP9 were obtained from the receiver operating characteristic curve. RESULTS: Of the 130 patients with LHI enrolled, 90 patients (69.2%) had 3-month poor outcome, and MCE occurred in 55 patients (42.3%). Patients with serum MIF concentrations ≤ 7.82 ng/mL for predicting 3-month poor outcome [adjusted odds ratio (OR) 2.827, 95% confidence interval (CI) 1.144-6.990, p = 0.024] also distinguished death (adjusted OR 4.329, 95% CI 1.841-10.178, p = 0.001). Similarly, MMP9 concentrations ≤ 46.56 ng/mL for predicting 3-month poor outcome (adjusted OR 2.814, 95% CI 1.236-6.406, p = 0.014) also distinguished 3-month death (adjusted OR 3.845, 95% CI 1.534-9.637, p = 0.004). CONCLUSIONS: Lower serum MIF and MMP9 concentrations at an early stage were independently associated with 3-month poor outcomes and death in patients with LHI. These findings need further confirmation in larger sample studies.

20.
J Pediatr Orthop ; 44(4): 236-243, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38298014

RESUMEN

OBJECTIVE: Closed or open reduction and spica casting are common treatments for children aged 6 to 18 months, as well as infants aged 0 to 6 months whose harness treatment for developmental dysplasia of the hip (DDH) was unsuccessful. The study aimed to quantify the distance between the femoral head and the acetabulum after closed or open reduction and evaluate the dynamic docking progression of the femoral head using serial hip medical ultrasound. METHODS: We retrospectively reviewed the medical records and hip medial ultrasound images of a consecutive series of patients with DDH who underwent spica casting after reduction and compared images obtained immediately after reduction and at follow-up. The first cast (stage I) was maintained for 2 to 3 months and scheduled for outpatient repeat ultrasound in 4 to 8 weeks. Then the second cast was placed (stage II), lasting for another 2 to 3 months. The triradiate cartilage-femoral head distance (TFD) was measured in the acetabulum coronal mid-sectional plane. The Wilcoxon signed-rank test was used to compare the TFD values. RESULTS: This study included 49 patients. All patients underwent hip medial ultrasound 0 to 3 days after stage I (time 1) and 4 to 8 weeks (time 2) postoperatively, with 24 patients reviewed again 0 to 7 days after stage II. The TFD values in time 1 and time 2 were 6.0 (5.0, 9.0) mm and 5.0 (3.6, 7.0) mm, respectively. There was a statistically significant difference between times 1 and 2 regarding TFD values in 49 close-reduction hips (6.0 vs 5.0 mm, P < 0.001). Similar findings were also observed in 13 open-reduction hips (6.0 vs 5.0 mm, P = 0.023). CONCLUSIONS: Hip medial ultrasonography during the period of cast immobilization after reduction in children with DDH can objectively and quantitatively show the dynamic change of the distance between the femoral head and the acetabulum, and can be used to assess reduction of the hip and progression of femoral head docking. LEVEL OF EVIDENCE: Level II-prognostic study.


Asunto(s)
Displasia del Desarrollo de la Cadera , Luxación Congénita de la Cadera , Lactante , Niño , Humanos , Luxación Congénita de la Cadera/terapia , Luxación Congénita de la Cadera/cirugía , Estudios de Seguimiento , Resultado del Tratamiento , Estudios Retrospectivos , Displasia del Desarrollo de la Cadera/diagnóstico por imagen , Displasia del Desarrollo de la Cadera/terapia , Ultrasonografía
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