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1.
Antonie Van Leeuwenhoek ; 118(1): 6, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39292388

RESUMEN

Two facultatively aerobic strains, designated SGZ-02T and SGZ-792T, were isolated from plant Pennisetum sp., exhibiting the highest 16S rRNA gene sequence similarities with the type strains of Sphingomonas zeae LMG 28739T (98.6%) and Massilia forsythiae NBRC 114511T (98.4%), respectively. SGZ-02T grew between 5 and 45 °C, pH 5.0-11.0 and tolerated NaCl concentrations of 0-4% (w/v), whereas SGZ-792T thrived at 5-40 °C, pH 5.0-11.0 and NaCl tolerance to 0-3.5% (w/v). The major quinone of SGZ-02T was ubiquinone-10, with the dominant fatty acids being C16:0 (13.5%), Summed Feature 3 (6.3%), C14:02-OH (5.3%) and Summed Feature 8 (66.3%). SGZ-792T predominantly contained ubiquinone-8, with major fatty acids being C16:0 (20.3%), Summed Feature 3 (5.0%) and Summed Feature 8 (54.7%). Average nucleotide identity and digital DNA-DNA hybridization values between two strains and their closest references strains were below the bacterial species threshold. Based on genotypic and phenotypic characteristics, strains SGZ-02T and SGZ-792T are proposed as novel species within the genera Sphingomonas and Massilia, respectively. The suggested names for the new species are Sphingomonas fuzhouensis sp. nov. (SGZ-02T = GDMCC 1.4033T = JCM 36769T) and Massilia phyllosphaerae sp. nov. (SGZ-792T = GDMCC 1.4211T = JCM 36643T), respectively.


Asunto(s)
ADN Bacteriano , Ácidos Grasos , Pennisetum , Filogenia , ARN Ribosómico 16S , Sphingomonas , Sphingomonas/genética , Sphingomonas/clasificación , Sphingomonas/aislamiento & purificación , Sphingomonas/fisiología , ARN Ribosómico 16S/genética , Pennisetum/microbiología , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , ADN Bacteriano/genética , Genoma Bacteriano , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis de Secuencia de ADN
2.
Diagn Microbiol Infect Dis ; 110(4): 116515, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39232452

RESUMEN

Pleural parasitic infection is an extremely rare disease of the pleura caused by a variety of parasites, with paragonimiasis infection being the most common. The lack of specific clinical symptoms for paragonimiasis makes it easy to misdiagnose as tuberculosis, causing unnecessary drug-related adverse effects and financial burdens from incorrect treatment. We report a case of a pediatric patient presenting with an isolated pleural effusion that was misdiagnosed as tuberculosis; the patient was eventually diagnosed with pleuropulmonary paragonimiasis infection after immunologic and serologic tests. The patient finally recovered after anti-parasitic treatment involving praziquantel administration. This report will help increase awareness of this disease among medical practitioners to avoid misdiagnosis and treatment delays which may lead to disease progression.

3.
BMC Sports Sci Med Rehabil ; 16(1): 163, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095858

RESUMEN

BACKGROUND: Fall prevention and balance control constitute critical components of rehabilitation for stroke survivors. Kneeling training, characterized by its low center of gravity focus, has been incorporated into rehabilitation regimens to enhance postural control across various pathological conditions. Despite its widespread use, empirical evidence substantiating the efficacy of kneeling training is limited, particularly in the context of mobility and balance improvement for patients who have had a stroke. This study aims to substantiate the safety and effectiveness of kneeling training in individuals recovering from stroke. METHODS: A randomized controlled trial comparing kneeling training and conventional rehabilitation training was conducted, involving sixty-seven participants allocated to the Kneeling Training Group (KNT) and the Conventional Rehabilitation Group (CVR). The KNT group underwent 30-minute sessions of kneeling training, while the CVR group received conventional treadmill walking training, both administered six times per week over four weeks. Evaluation encompassed the Fugl-Meyer Assessment for Lower Extremity (FMA-LE), the Berg Balance Scale (BBS), and gait analysis was conducted at baseline, as well as at the 2 and 4-week intervals. RESULTS: Our study established the safety of a 4-week kneeling training program. Notably, the KNT group exhibited more pronounced improvements in BBS scores at weeks 2 and 4 compared to the CVR group. However, no significant disparities emerged in FMA-LE and gait analysis between the two groups. Our findings suggest that kneeling training may serve as a viable option for enhancing lower limb balance in survivors who have had a stroke. CONCLUSIONS: We conclude that kneeling training, characterized by its safety, simplicity, and no restrictions on location or equipment, represents a valuable therapeutic approach for enhancing walking balance in individuals recovering from stroke. TRIAL REGISTRATION: Clinical trials ChiCTR1900028385, December 20, 2019.

4.
mSystems ; 9(9): e0060724, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39166877

RESUMEN

The global rise of antibiotic resistance has renewed interest in phage therapy, as an alternative to antibiotics to eliminate multidrug-resistant (MDR) bacterial pathogens. However, optimizing the broad-spectrum efficacy of phage therapy remains a challenge. In this study, we addressed this issue by employing strategies to improve antimicrobial efficacy of phage therapy against MDR Klebsiella pneumoniae strains, which are notorious for their resistance to conventional antibiotics. This includes the selection of broad host range phages, optimization of phage formulation, and combinations with last-resort antibiotics. Our findings unveil that having a broad host range was a dominant trait of isolated phages, and increasing phage numbers in combination with antibiotics significantly enhanced the suppression of bacterial growth. The decreased incidence of bacterial infection was explained by a reduction in pathogen density and emergence of bacterial resistance. Furthermore, phage-antibiotic synergy (PAS) demonstrated considerable broad-spectrum antibacterial potential against different clades of clinical MDR K. pneumoniae pathogens. The improved treatment outcomes of optimized PAS were also evident in a murine model, where mice receiving optimized PAS therapy demonstrated a reduced bacterial burden in mouse tissues. Taken together, these findings offer an important development in optimizing PAS therapy and its efficacy in the elimination of MDR K. pneumoniae pathogens. IMPORTANCE: The worldwide spread of antimicrobial resistance (AMR) has posed a great challenge to global public health. Phage therapy has become a promising alternative against difficult-to-treat pathogens. One important goal of this study was to optimize the therapeutic efficiency of phage-antibiotic combinations, known as phage-antibiotic synergy (PAS). Through comprehensive analysis of the phenotypic and genotypic characteristics of a large number of CRKp-specific phages, we developed a systematic model for phage cocktail combinations. Crucially, our finding demonstrated that PAS treatments not only enhance the bactericidal effects of colistin and tigecycline against multidrug-resistant (MDR) K. pneumoniae strains in in vitro and in vivo context but also provide a robust response when antibiotics fail. Overall, the optimized PAS therapy demonstrates considerable potential in combating diverse K. pneumoniae pathogens, highlighting its relevance as a strategy to mitigate antibiotic resistance threats effectively.


Asunto(s)
Antibacterianos , Bacteriófagos , Farmacorresistencia Bacteriana Múltiple , Infecciones por Klebsiella , Klebsiella pneumoniae , Terapia de Fagos , Klebsiella pneumoniae/virología , Klebsiella pneumoniae/efectos de los fármacos , Animales , Antibacterianos/farmacología , Terapia de Fagos/métodos , Ratones , Infecciones por Klebsiella/terapia , Infecciones por Klebsiella/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Femenino
5.
Appl Environ Microbiol ; 90(8): e0069524, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39078126

RESUMEN

While the distribution of extracellular ARGs (eARGs) in the environment has been widely reported, the factors governing their release remain poorly understood. Here, we combined multi-omics and direct experimentation to test whether the release and transmission of eARGs are associated with viral lysis and heat during cow manure composting. Our results reveal that the proportion of eARGs increased 2.7-fold during composting, despite a significant and concomitant reduction in intracellular ARG abundances. This relative increase of eARGs was driven by composting temperature and viral lysis of ARG-carrying bacteria based on metagenome-assembled genome (MAG) analysis. Notably, thermal lysis of mesophilic bacteria carrying ARGs was a key factor in releasing eARGs at the thermophilic phase, while viral lysis played a relatively stronger role during the non-thermal phase of composting. Furthermore, MAG-based tracking of ARGs in combination with direct transformation experiments demonstrated that eARGs released during composting pose a potential transmission risk. Our study provides bioinformatic and experimental evidence of the undiscovered role of temperature and viral lysis in co-driving the spread of ARGs in compost microbiomes via the horizontal transfer of environmentally released DNA. IMPORTANCE: The spread of antibiotic resistance genes (ARGs) is a critical global health concern. Understanding the factors influencing the release of extracellular ARGs (eARGs) is essential for developing effective strategies. In this study, we investigated the association between viral lysis, heat, and eARG release during composting. Our findings revealed a substantial increase in eARGs despite reduced intracellular ARG abundance. Composting temperature and viral lysis were identified as key drivers, with thermal lysis predominant during the thermophilic phase and viral lysis during non-thermal phases. Moreover, eARGs released during composting posed a transmission risk through horizontal gene transfer. This study highlights the significance of temperature and phage lysis in ARG spread, providing valuable insights for mitigating antibiotic resistance threats.


Asunto(s)
Compostaje , Transferencia de Gen Horizontal , Estiércol/microbiología , Estiércol/virología , Microbiología del Suelo , Bacterias/genética , Bacterias/efectos de los fármacos , Animales , Metagenoma , Bovinos , Calor , Genes Bacterianos , Farmacorresistencia Microbiana/genética , Farmacorresistencia Bacteriana/genética , Microbiota , Bacteriófagos/genética , Bacteriófagos/fisiología
6.
J Alzheimers Dis ; 100(3): 911-921, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38968047

RESUMEN

Background: Urinary Alzheimer-associated neuronal thread protein (AD7c-NTP) is a biomarker for the early diagnosis of Alzheimer's disease (AD). It remains unclear whether hepatorenal function affects the urinary AD7c-NTP level. Objective: To evaluate the effects of hepatorenal function on urinary AD7c-NTP level. Methods: We enrolled 453 participants aged 60-100 years. An automated chemistry analyzer was used to determine the indicators of serum hepatorenal function. Enzyme-linked immunosorbent assay was used to measure the urinary AD7c-NTP level. Results: Spearman's correlation analysis showed a negative correlation between urinary AD7c-NTP levels and indicators of hepatorenal function, including albumin (r = -0.181, p < 0.001), albumin/globulin ratio (r = -0.224, p < 0.001), cholinesterase (r = -0.094, p = 0.046), total carbon dioxide (r = -0.102, p = 0.030), and glomerular filtration rate (r = -0.260, p < 0.001), as well as a positive correlation with globulin (r = 0.141, p = 0.003), aspartate transaminase (r = 0.186, p < 0.001), blood urine nitrogen (r = 0.210, p < 0.001), creatinine (r = 0.202, p < 0.001), uric acid (r = 0.229, p < 0.001), and cystatin C (r = 0.265, p < 0.001). The least absolute shrinkage and selection operator (LASSO) regression analysis and multiple linear regression model analyses showed that the statistically significant hepatorenal indicators for predicting AD7c-NTP were A/G (p = 0.007), AST (p = 0.002), BUN (p = 0.019), and UA (p = 0.003). Conclusions: The effects of hepatorenal indicators should be considered when using urinary AD7c-NTP levels in clinical settings.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Alzheimer/orina , Enfermedad de Alzheimer/diagnóstico , Biomarcadores/orina , Biomarcadores/sangre , China/epidemiología , Estudios Transversales , Cistatina C/sangre , Cistatina C/orina , Pueblos del Este de Asia , Tasa de Filtración Glomerular/fisiología , Riñón/fisiopatología , Pruebas de Función Hepática , Proteínas del Tejido Nervioso/orina
7.
ISME J ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39030691

RESUMEN

Arthropods, such as houseflies, play a significant role on the dissemination of antimicrobial resistance (AMR); however, their impact has often been overlooked in comparison to other AMR vectors. Understanding the contribution of arthropods to the spread of AMR is critical for implementing robust policies to mitigate the spread of AMR across "One Health" sectors. Herein, we investigated the in-situ transfer of a gfp-labelled AMR plasmid (IncA/C carrying a mcr-8 gene, pA/C_MCR-8) in the gut microbiota of housefly (Musca domestica) by applying single-cell sorting, 16S rRNA gene amplicon sequencing, and whole genome sequencing. Our findings demonstrate that the pA/C_MCR-8 positive E. coli donor strain is capable of colonizing the gut microbiome of houseflies and persists in the housefly intestine for five days, however, no transfer was detectable above the detection threshold of 10-5 per cell. The conjugative plasmid, pA/C_MCR-8 demonstrated a high transfer frequency ranging from 4.1 × 10-3 to 5.0 × 10-3 per cell in vitro, and exhibited transfer across various bacterial phyla, primarily encompassing Pseudomonadota and Bacillota. Phylogenic analysis has revealed that Providencia stuartii, a human opportunistic pathogen, was a notable recipient of pA/C_MCR-8. The conjugation assays further revealed that newly formed P. stuartii transconjugants readily transfer pA/C_MCR-8 to other clinically relevant pathogens (e.g. Klebsiella pneumoniae). Our findings indicate the potential transfer of AMR plasmids from houseflies to human opportunistic pathogens and further advocates the adoption of a One Health approach in developing infection control policies that address AMR across clinical settings.

8.
Nat Commun ; 15(1): 4862, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862464

RESUMEN

As spaceflight becomes more common with commercial crews, blood-based measures of crew health can guide both astronaut biomedicine and countermeasures. By profiling plasma proteins, metabolites, and extracellular vesicles/particles (EVPs) from the SpaceX Inspiration4 crew, we generated "spaceflight secretome profiles," which showed significant differences in coagulation, oxidative stress, and brain-enriched proteins. While >93% of differentially abundant proteins (DAPs) in vesicles and metabolites recovered within six months, the majority (73%) of plasma DAPs were still perturbed post-flight. Moreover, these proteomic alterations correlated better with peripheral blood mononuclear cells than whole blood, suggesting that immune cells contribute more DAPs than erythrocytes. Finally, to discern possible mechanisms leading to brain-enriched protein detection and blood-brain barrier (BBB) disruption, we examined protein changes in dissected brains of spaceflight mice, which showed increases in PECAM-1, a marker of BBB integrity. These data highlight how even short-duration spaceflight can disrupt human and murine physiology and identify spaceflight biomarkers that can guide countermeasure development.


Asunto(s)
Coagulación Sanguínea , Barrera Hematoencefálica , Encéfalo , Homeostasis , Estrés Oxidativo , Vuelo Espacial , Animales , Humanos , Encéfalo/metabolismo , Barrera Hematoencefálica/metabolismo , Ratones , Coagulación Sanguínea/fisiología , Masculino , Secretoma/metabolismo , Ratones Endogámicos C57BL , Vesículas Extracelulares/metabolismo , Proteómica/métodos , Biomarcadores/metabolismo , Biomarcadores/sangre , Femenino , Adulto , Proteínas Sanguíneas/metabolismo , Persona de Mediana Edad , Leucocitos Mononucleares/metabolismo , Proteoma/metabolismo
9.
Nat Commun ; 15(1): 5498, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38944647

RESUMEN

IncX3 plasmids carrying the New Delhi metallo-ß-lactamase-encoding gene, blaNDM-5, are rapidly spreading globally in both humans and animals. Given that carbapenems are listed on the WHO AWaRe watch group and are prohibited for use in animals, the drivers for the successful dissemination of Carbapenem-Resistant Enterobacterales (CRE) carrying blaNDM-5-IncX3 plasmids still remain unknown. We observe that E. coli carrying blaNDM-5-IncX3 can persist in chicken intestines either under the administration of amoxicillin, one of the largest veterinary ß-lactams used in livestock, or without any antibiotic pressure. We therefore characterise the blaNDM-5-IncX3 plasmid and identify a transcription regulator, VirBR, that binds to the promoter of the regulator gene actX enhancing the transcription of Type IV secretion systems (T4SS); thereby, promoting conjugation of IncX3 plasmids, increasing pili adhesion capacity and enhancing the colonisation of blaNDM-5-IncX3 transconjugants in animal digestive tracts. Our mechanistic and in-vivo studies identify VirBR as a major factor in the successful spread of blaNDM-5-IncX3 across one-health AMR sectors. Furthermore, VirBR enhances the plasmid conjugation and T4SS expression by the presence of copper and zinc ions, thereby having profound ramifications on the use of universal animal feeds.


Asunto(s)
Antibacterianos , Pollos , Conjugación Genética , Escherichia coli , Plásmidos , beta-Lactamasas , Animales , Plásmidos/genética , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Pollos/microbiología , Humanos , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Antibacterianos/farmacología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Sistemas de Secreción Tipo IV/genética , Sistemas de Secreción Tipo IV/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Amoxicilina/farmacología , Regiones Promotoras Genéticas/genética , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/transmisión , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Intestinos/microbiología
10.
Front Public Health ; 12: 1321123, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784570

RESUMEN

Background: Scrub typhus, caused by the Orientia tsutsugamushi (Ot), is a widespread vector-borne disease transmitted by chigger mites. Hemophagocytic lymphohistiocytosis (HLH) is considered to be one of the potentially severe complications. The diagnosis of scrub typhus-associated HLH may be overlooked due to the non-specific clinical characteristics and the absence of pathognomonic eschar. Case presentation: We obtained clinical data from two patients in the South of Sichuan, China. The first case involved a 6-year-old girl who exhibited an unexplained fever and was initially diagnosed with sepsis, HLH, and pulmonary infection. The other patient presented a more severe condition characterized by multiple organ dysfunction and was initially diagnosed with septic shock, sepsis, HLH, acute kidney injury (AKI), and pulmonary infection. At first, a specific examination for scrub typhus was not performed due to the absence of a characteristic eschar. Conventional peripheral blood cultures yielded negative results in both patients, and neither of them responded to routine antibiotics. Fortunately, the causative pathogen Orientia tsutsugamushi (Ot) was detected in the plasma samples of both patients using metagenomics next-generation sequencing (mNGS) and further confirmed by polymerase chain reaction. Subsequently, they both were treated with doxycycline and recovered quickly. Conclusion: The unbiased mNGS provided a clinically actionable diagnosis for an uncommon pathogen-associated infectious disease that had previously evaded conventional diagnostic approaches.


Asunto(s)
Linfohistiocitosis Hemofagocítica , Orientia tsutsugamushi , Tifus por Ácaros , Tifus por Ácaros/diagnóstico , Tifus por Ácaros/complicaciones , Humanos , Femenino , Niño , Orientia tsutsugamushi/aislamiento & purificación , Orientia tsutsugamushi/genética , Linfohistiocitosis Hemofagocítica/diagnóstico , China , Masculino , Doxiciclina/uso terapéutico
11.
Nat Commun ; 15(1): 3654, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38688912

RESUMEN

The horizontal transfer of plasmids has been recognized as one of the key drivers for the worldwide spread of antimicrobial resistance (AMR) across bacterial pathogens. However, knowledge remain limited about the contribution made by environmental stress on the evolution of bacterial AMR by modulating horizontal acquisition of AMR plasmids and other mobile genetic elements. Here we combined experimental evolution, whole genome sequencing, reverse genetic engineering, and transcriptomics to examine if the evolution of chromosomal AMR to triclosan (TCS) disinfectant has correlated effects on modulating bacterial pathogen (Klebsiella pneumoniae) permissiveness to AMR plasmids and phage susceptibility. Herein, we show that TCS exposure increases the evolvability of K. pneumoniae to evolve TCS-resistant mutants (TRMs) by acquiring mutations and altered expression of several genes previously associated with TCS and antibiotic resistance. Notably, nsrR deletion increases conjugation permissiveness of K. pneumoniae to four AMR plasmids, and enhances susceptibility to various Klebsiella-specific phages through the downregulation of several bacterial defense systems and changes in membrane potential with altered reactive oxygen species response. Our findings suggest that unrestricted use of TCS disinfectant imposes a dual impact on bacterial antibiotic resistance by augmenting both chromosomally and horizontally acquired AMR mechanisms.


Asunto(s)
Bacteriófagos , Klebsiella pneumoniae , Plásmidos , Triclosán , Triclosán/farmacología , Plásmidos/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/virología , Bacteriófagos/genética , Bacteriófagos/fisiología , Farmacorresistencia Bacteriana Múltiple/genética , Mutación , Transferencia de Gen Horizontal , Secuenciación Completa del Genoma , Evolución Molecular , Antibacterianos/farmacología
13.
PeerJ ; 12: e17137, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529310

RESUMEN

Gleditsia sinensis, commonly known as Chinese Zaojiao, has important economic value and medicinal compounds in its fruits and thorns, making it widely cultivated artificially in China. However, the available literature on the impact of waterlogging on the growth of G. sinensis seedlings and the accumulation of metabolite compounds in its thorns is limited. To address this knowledge gap, G. sinensis seedlings were planted in soil supplemented with pindstrup substrate, which enhances the water-holding capacity of the soil. The analyses of morphological traits and nutrient elements in one-year-old G. sinensis seedlings grown naturally under ambient conditions and metabolite accumulation in its thorns were conducted. The results showed that the waterlogged soil significantly diminished the height, fresh weight, and dry weight of seedling roots and stems (P < 0.05). Furthermore, waterlogging hindered the uptake of iron (Fe) and manganese (Mn), as well as the transport of potassium (K). The identified metabolites within the thorns were categorized into 16 distinct groups. Relative to the control soil, fatty acids and derivatives were the most down-regulated metabolites in the waterlogged soil, accounting for 40.58% of the total metabolites, followed by lignans (38.71%), phenolic acids (34.48%), saccharides and alcohols (34.15%), steroids (16.67%), alkaloids (12.24%), flavonoids (9.28%), and glycerophospholipids (7.41%). Conversely, nucleotides and derivatives experienced the greatest up-regulation in the waterlogged soil, accounting for 50.00% of the total metabolites. In conclusion, waterlogging negatively impacted the growth of G. sinensis seedlings and inhibited the accumulation of metabolites. Hence, when considering the accumulation of secondary metabolites such as lignans and phenolic acids, appropriate management of soil moisture levels should be taken into account.


Asunto(s)
Gleditsia , Lignanos , Plantones , Lignanos/metabolismo , Gleditsia/química , Extractos Vegetales/metabolismo , Raíces de Plantas
14.
Enzyme Microb Technol ; 175: 110410, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38340378

RESUMEN

Prunin of desirable bioactivity and bioavailability can be transformed from plant-derived naringin by the key enzyme α-L-rhamnosidase. However, the production was limited by unsatisfactory properties of α-L-rhamnosidase such as thermostability and organic solvent tolerance. In this study, biochemical characteristics, and hydrolysis capacity of a novel α-L-rhamnosidase from Spirochaeta thermophila (St-Rha) were investigated, which was the first characterized α-L-rhamnosidase for Spirochaeta genus. St-Rha showed a higher substrate specificity towards naringin and exhibited excellent thermostability and methanol tolerance. The Km of St-Rha in the methanol cosolvent system was decreased 7.2-fold comparing that in the aqueous phase system, while kcat/Km value of St-Rha was enhanced 9.3-fold. Meanwhile, a preliminary conformational study was implemented through comparative molecular dynamics simulation analysis to explore the mechanism underlying the methanol tolerance of St-Rha for the first time. Furthermore, the catalytic ability of St-Rha for prunin preparation in the 20% methanol cosolvent system was explored, and 200 g/L naringin was transformed into 125.5 g/L prunin for 24 h reaction with a corresponding space-time yield of 5.2 g/L/h. These results indicated that St-Rha was a novel α-L-rhamnosidase suitable for hydrolyzing naringin in the methanol cosolvent system and provided a better alternative for improving the efficient production yield of prunin.


Asunto(s)
Florizina/análogos & derivados , Spirochaeta , Metanol , Glicósido Hidrolasas/química , Solventes
15.
Plant Physiol Biochem ; 207: 108426, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38340689

RESUMEN

In nature, light intensity usually fluctuates and a sudden shade-sun transition can induce photodamage to photosystem I (PSI) in many angiosperms. Photosynthetic regulation in fluctuating light (FL) has been studied extensively in C3 plants; however, little is known about how C4 plants cope FL to prevent PSI photoinhibition. We here compared photosynthetic responses to FL between maize (Zea mays, C4) and tomato (Solanum lycopersicum, C3) grown under full sunlight. Maize leaves had significantly higher cyclic electron flow (CEF) activity and lower photorespiration activity than tomato. Upon a sudden shade-sun transition, maize showed a significant stronger transient PSI over-reduction than tomato, resulting in a significant greater PSI photoinhibition in maize after FL treatment. During the first seconds upon shade-sun transition, CEF was stimulated in maize at a much higher extent than tomato, favoring the rapid formation of trans-thylakoid proton gradient (ΔpH), which was helped by a transient down-regulation of chloroplast ATP synthase activity. Therefore, modulation of ΔpH by regulation of CEF and chloroplast ATP synthase adjusted PSI redox state at donor side, which partially compensated for the deficiency of photorespiration. We propose that C4 plants use different photosynthetic strategies for coping with FL as compared with C3 plants.


Asunto(s)
Complejo de Proteína del Fotosistema I , Zea mays , Complejo de Proteína del Fotosistema I/metabolismo , Zea mays/metabolismo , ATPasas de Translocación de Protón de Cloroplastos , Fotosíntesis/fisiología , Luz , Transporte de Electrón , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-38323900

RESUMEN

Three microaerophilic bacterial strains, designated SG22T, SG63T and SG29T were isolated from paddy soils in PR China. Cells of these strains were Gram-staining-negative and long rod-shaped. SG22T, SG63T and SG29T showed the highest 16S rRNA gene sequence similarities with the members of the genus Anaeromyxobacter. The results of phylogenetic and phylogenomic analysis also indicated that these strains clustered with members of the genus Anaeromyxobacter. The main respiratory menaquinone of SG22T, SG63T and SG29T was MK-8 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 and C16 : 0. SG22T, SG29T and SG63T not only possessed iron reduction ability but also harboured genes (nifHDK) encoding nitrogenase. The genomic DNA G+C contents of SG22T, SG63T and SG29T ranged from 73.3 to 73.5 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between SG22T, SG63T and SG29T and the closely related species of the genus Anaeromyxobacter were lower than the cut-off values (dDDH 70 % and ANI 95-96 %) for prokaryotic species delineation. On the basis of these results, strains SG22T, SG63T and SG29T represent three novel species within the genus Anaeromyxobacter, for which the names Anaeromyxobacter terrae sp. nov., Anaeromyxobacter oryzisoli sp. nov. and Anaeromyxobacter soli sp. nov., are proposed. The type strains are SG22T (= GDMCC 1.3185T = JCM 35581T), SG63T (= GDMCC 1.2914T = JCM 35124T) and SG29T (= GDMCC 1.2911T = JCM 35123T).


Asunto(s)
Myxococcales , Bacterias Fijadoras de Nitrógeno , Compuestos Férricos , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Ácidos Grasos/química , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Nucleótidos , Suelo
17.
Phys Chem Chem Phys ; 26(8): 6956-6966, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38334722

RESUMEN

The investigation and development of high thermoelectric value materials has become a research hotspot in recent years. In this work, based on the density functional theory on the Perdew-Burke-Ernzerhof (GGA-PBE) level, the thermoelectric properties of transition metal halides CdBr, Janus Cd2BrI, and CdI monolayers have been systematically investigated using Boltzmann transport theory. The calculation of the electronic band structure shows that these three materials have indirect band gap semiconductor properties. For carrier transport, the electron mobilities for CdBr, Janus Cd2BrI, and CdI monolayers are found to be 74, 16, 21 cm2 s-1 V-1 for p-type doping and 116, 102, 78 cm2 s-1 V-1 for n-type doping. Regarding their phonon transport, the CdBr, Cd2BrI, and CdI monolayers all have very low lattice thermal conductivity (4.78, 2.46, and 1.65 W m-1 K-1, respectively) that decreases with increasing temperature, which is favorable for obtaining large zT values. The electrical transport results show that the performance of p-type doping is better than that of n-type doping. At 300 K, the Seebeck coefficients of p-type doping for the CdBr, Cd2BrI, and CdI monolayers are 217.72, 246.43, and 226.24 µV K-1, respectively. In addition, we predict that the zT values of the CdBr, Cd2BrI, and CdI monolayers are 0.62, 1.64, and 0.87 for p-type doping at 300 K respectively. The zT values increase with the increase of temperature. In particular, the Janus Cd2BrI monolayer has a zT value of 3.03 at 600 K. These results suggest that all these materials can be good candidates for thermoelectric materials.

18.
Jpn J Infect Dis ; 77(4): 240-243, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38417866

RESUMEN

Patients with acquired immune deficiency syndrome (AIDS) are susceptible to numerous complications, such as sepsis and acute kidney injury (AKI), leading to adverse outcomes. Continuous renal replacement therapy (CRRT) is becoming increasingly popular for treating sepsis and AKI. This study aimed to verify the effectiveness of CRRT in the treatment of patients with AIDS with sepsis and AKI to provide new directions for the treatment of severe AIDS. Data of 74 people with AIDS, sepsis, and AKI were collected. The patients were divided into CRRT and non-CRRT groups. There was no difference in the indicators between the two groups at admission. Vital signs, pH, serum potassium level, renal function, blood lactate level, acute physiology and chronic health evaluation II score, and sequential organ failure assessment score in the CRRT group demonstrated significant improvements over those in the non-CRRT group at both 24 and 72 h after admission (P < 0.05). The levels of interleukin 6 and procalcitonin declined more significantly in the CRRT group at 72 h after admission (P < 0.05). The CRRT group had a higher 28-day survival rate than the non-CRRT group (P < 0.05). CRRT improves the clinical indicators and increases the short-term survival rate of patients with AIDS, sepsis, and AKI.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Lesión Renal Aguda , Terapia de Reemplazo Renal Continuo , Sepsis , Humanos , Lesión Renal Aguda/terapia , Lesión Renal Aguda/mortalidad , Sepsis/terapia , Sepsis/mortalidad , Sepsis/complicaciones , Masculino , Femenino , Persona de Mediana Edad , Terapia de Reemplazo Renal Continuo/métodos , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Adulto , Resultado del Tratamiento , Análisis de Supervivencia , Anciano
19.
Plant Sci ; 341: 112014, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38309473

RESUMEN

Brassinosteroids (BRs) function importantly in plant growth and development, but the roles in regulating fruit development and anthocyanin pigmentation remain unclear. Eggplant (Solanum melongena L.) is an important Solanaceae vegetable crop rich in anthocyanins. The fruit size and coloration are important agronomic traits for eggplant breeding. In this study, transgenic eggplant exhibiting endogenous BRs deficiency was created by overexpressing a heterologous BRs-inactivating enzyme gene GhPAG1 driven by CaMV 35 S promoter. 35 S::GhPAG1 eggplant exhibited severe dwarfism, reduced fruit size, and less anthocyanin accumulation. Microscopic observation showed that the cell size of 35 S::GhPAG1 eggplant was significantly reduced compared to WT. Furthermore, the levels of IAA, ME-IAA, and active JAs (JA, JA-ILE, and H2JA) all decreased in 35 S::GhPAG1 eggplant fruit. RNA-Seq analyses showed a decrease in the expression of genes involved in cell elongation, auxin signaling, and JA signaling. Besides, overexpression of GhPAG1 significantly downregulated anthocyanin biosynthetic genes and associated transcription regulators. Altogether, these results strongly suggest that endogenous brassinosteroid deficiency arising from GhPAG1 overexpression impacts eggplant fruit development and anthocyanin coloration mainly by altering hormone homeostasis.


Asunto(s)
Antocianinas , Solanum melongena , Antocianinas/metabolismo , Solanum melongena/genética , Solanum melongena/metabolismo , Frutas/metabolismo , Fitomejoramiento , Hormonas/metabolismo , Homeostasis , Regulación de la Expresión Génica de las Plantas
20.
BMC Genomics ; 25(1): 206, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395755

RESUMEN

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with a five-year survival rate of approximately 10%. Genetic mutations are pivotal drivers in PDAC pathogenesis, but recent investigations also revealed the involvement of non-genetic alterations in the disease development. In this study, we undertook a multi-omics approach, encompassing ATAC-seq, RNA-seq, ChIP-seq, and Hi-C methodologies, to dissect gene expression alterations arising from changes in chromosome accessibility and chromatin three-dimensional interactions in PDAC. RESULTS: Our findings indicate that chromosomal structural alterations can lead to abnormal expressions on key genes during PDAC development. Notably, overexpression of oncogenes FGFR2, FOXA2, CYP2R1, and CPOX can be attributed to the augmentation of promoter accessibility, coupled with long-range interactions with distal elements. Additionally, our findings indicate that chromosomal structural alterations caused by genomic instability can lead to abnormal expressions in PDACs. As an example, by analyzing chromosomal changes, we identified a putative oncogenic gene, LPAR1, which shows upregulated expression in both PDAC cell lines and clinical samples. The overexpression is correlated with alterations in LPAR1-associated 3D genome structure and chromatin state. We further demonstrated that high LPAR1 activity is required for enhanced PDAC cell migration in vitro. CONCLUSIONS: Collectively, our findings reveal that the chromosomal conformational alterations, in addition to the well-known genetic mutations, are critical for PDAC tumorigenesis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/genética , Carcinogénesis/genética , Expresión Génica , Cromatina/genética , Regulación Neoplásica de la Expresión Génica
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