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1.
J Phys Chem A ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839423

RESUMO

Recently, Guha and co-workers (Sarmah, K.; Kalita, A.; Purkayastha, S.; Guha, A. K. Pushing The Extreme of Multicentre Bonding: Planar Pentacoordinate Hydride. Angew. Chem. Int. Ed. 2024, e202318741) reported a highly intriguing bonding motif: planar pentacoordinate hydrogen (ppH) in Li5H6-, featuring C2v symmetry in the singlet state with two distinct H-Li (center-ring) bond distances. We herein revisited the potential energy surface of Li5H6- by using a target-oriented genetic algorithm. Our investigation revealed that the lowest-energy structure of Li5H6- exhibits a ppH configuration with very high D5h symmetry and a 1A1' electronic state. We did not find any electronic effect like Jahn-Teller distortion that could be responsible for lowering its symmetry. Moreover, our calculations demonstrated significant differences in the relative energies of other low-lying isomers. An energetically very competitive planar tetracoordinate hydrogen (ptH) isomer is also located, but it corresponds to a very shallow minimum on the potential energy surface depending on the used level of theory. Chemical bonding analyses, including AdNDP and EDA-NOCV, uncover that the optimal Lewis structure for Li5H6- involves H- ions stabilized by the Li5H5 crown. Surprisingly, despite the dominance of electrostatic interactions, the contribution from covalent bonding is also significant between ppH and the Li5H5 moiety, derived from H-(1s) → Li5H5 σ donation. Magnetically induced current density analysis revealed that due to minimal orbital overlap and the highly polar nature of the H-Li covalent interaction, the ppH exhibits local diatropic ring currents around the H centers, which fails to result in a global aromatic ring current. The coordination of Li5H6- with Lewis acids, BH3 and BMe3, instantly converts the ppH configuration to (quasi) ptH. These Lewis acid-bound ptH complexes show high electronic stability and high thermochemical stability against dissociation and, therefore, will be ideal candidates for the experimental realization.

2.
Front Vet Sci ; 11: 1397166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840634

RESUMO

Avian coccidiosis, a parasitic disease prevalent in poultry, is caused by Eimeria species and leads to significant economic losses. The use of attenuated live oocyst vaccines has been adopted as an alternative to the use of anticoccidial drugs. However, the accurate detection and differentiation of vaccine strains from virulent ones remain challenging. Therefore, this study presents a novel TaqMan polymerase chain reaction (PCR) detection method that offers enhanced sensitivity, specificity, and reproducibility compared with traditional PCR techniques. Through whole-genome resequencing and bioinformatics analysis, we identified a molecular marker gene, Em_marker6, with a unique 21-base pair deletion specific to the Eimeria maxima attenuated vaccine strain. Optimized primers and probes targeting this marker enabled rapid quantification cycle value achievement and high fluorescence intensity. The standard curve's slope of -3.540 and correlation coefficient of 0.9971 confirmed precise quantification capabilities. The TaqMan PCR method detected as few as 30 plasmid DNA copies and 50 oocysts per reaction, outperforming traditional PCR techniques by an order of magnitude. No cross-reactivity was observed with other E. maxima wide-type strains or common intestinal pathogens, ensuring the exclusive detection of the E. maxima EMPY vaccine strain. Weekly testing over 3 weeks demonstrated minimal variability, indicating robust consistency in the method's application. Testing on 61 clinical samples revealed a 57.38% positivity rate for E. maxima species and 13.11% for the vaccine strain. The Em_marker6 gene exhibited genetic stability across multiple generations, confirming the detection method's robust stability for the attenuated E. maxima vaccine strain. This study significantly advances the field of avian coccidiosis research and control by providing a valuable tool for monitoring vaccine purity and preventing inadvertent infections in vaccinated flocks, aligning with global efforts to curb antibiotic use in animal feed.

3.
Heliyon ; 10(11): e31863, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38841444

RESUMO

Background: Few studies have examined the correlation between body mass index (BMI) and effectiveness of first-line chemoimmunotherapy in patients with advanced non-small cell lung cancer (NSCLC); moreover, the conclusion remains elusive and no such studies have been conducted in the Chinese population. Our study aimed to validate the predictive significance of BMI in Chinese patients with advanced NSCLC receiving first-line chemoimmunotherapy combinations. Methods: Data of patients with advanced NSCLC treated with first-line chemoimmunotherapy between June 2018 and February 2022 at three centers were retrieved retrospectively. The association between baseline BMI with progression-free survival (PFS) and overall survival (OS) was evaluated using the Kaplan-Meier method and Cox regression models. BMI was categorized according to the World Health Organization criteria. Results: Of the included 805 patients, 5.3 % were underweight, 63.4 % had normal weight, 27.8 % were overweight, and 3.5 % were obese. Survival analysis showed that patients in the high BMI group had significantly better PFS (p = 0.012) and OS (p = 0.014) than those in the low BMI group. Further, patients in the overweight subgroup had better PFS (p = 0.036) and OS (p = 0.043) compared to the normal weight population. The results of Cox regression analysis confirmed the correlations between BMI and prognosis of advanced NSCLC patients receiving first-line chemoimmunotherapy combinations. Conclusions: Baseline BMI affected the clinical outcomes of first-line chemoimmunotherapy combinations in patients with advanced NSCLC, and was especially favorable for the overweight subgroup.

4.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843775

RESUMO

The quest for planar hypercoordinate atoms (phA) beyond six has predominantly focused on transition metals, with dodecacoordination being the highest reported thus far. Extending this bonding scenario to main-group elements, which typically lack d orbitals despite their larger atomic radius, has posed significant challenges. Intrigued by the potentiality of covalent bonding formation using the d orbitals of the heavier alkaline-earth metals (Ae = Ca, Sr, Ba), the so-called "honorary transition metals", we aim to push the boundaries of planar hypercoordination. By including rings formed by 12-15 atoms of boron-carbon and Ae centers, we propose a design scheme of 180 candidates with a phA. Further systematic screening, structural examination, and stability assessments identified 10 potential clusters with a planar hypercoordinate alkaline-earth metal (phAe) as the lowest-energy form. These unconventional structures embody planar dodeca-, trideca-, tetradeca-, and pentadecacoordinate atoms. Chemical bonding analyses reveal the important role of Ae d orbitals in facilitating covalent interactions between the central Ae atom and the surrounding boron-carbon rings, thereby establishing a new record for coordination numbers in the two-dimensional realm.

5.
Neuroscience ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38843985

RESUMO

APOE ε4 is risk for cognitive decline even in normal aging, but its effect on the whole-brain functional connectivity (FC) among time in young adults remain elusive. This study aimed to validate the time-by-APOE ε4 interaction on brain FC of this specific population. Longitudinal changes in neuropsychological assessments and resting-state functional magnetic resonance imaging in 26 ε4 carriers and 26 matched non-ε4 carriers were measured for about 3 years. Whole-brain FC was calculated, and a full factorial design was used to compare the difference among groups. Two-sample t test was used for post-hoc analysis. Pearson's correlation analysis was conducted to investigate the relationships between FC and cognitive tests. Of 26 specially appointed ROIs, left superior temporal gyrus (TG) was most sensitive to the effect of time-by-gene interaction. Specifically, the alteration of FC was distributed between the left TG and right TG with GRF correction (voxel-P < 0.001, cluster-P < 0.05), and decreased in ε4 carriers while increased in non-ε4. The main effect of gene showed ε4 carriers has lower FC between left TG and right middle frontal gyrus as compared with non-ε4 both at baseline and follow-up study; ε4 carriers has lower FC between left TG and right supramarginal as compared with non-ε4 at baseline, but no difference in follow-up study. The time-by-APOE ε4 interaction on brain FC was demonstrated at a young age, and left TG was the earliest affected brain regions. The young adult ε4 carriers experience decreased FC among time in the absence overt clinical symptoms.

7.
Diagn Interv Radiol ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38836436

RESUMO

PURPOSE: Systemic inflammation and body composition are associated with survival outcomes of cancer patients. This study aimed to examine the combined prognostic value of systemic inflammatory markers and body composition parameters in patients with locally advanced cervical cancer (LACC). METHODS: Patients who underwent concurrent chemoradiotherapy (CCRT) for LACC at a tertiary referral teaching hospital between January 2010 and January 2018 were enrolled. A predictive model was established based on systemic immune-inflammation index (SII) and computer tomography-derived visceral fat-to-muscle ratio (vFMR). Overall survival (OS) and progression-free survival (PFS) were assessed using the Kaplan-Meier method and Cox regression models. The model performance was assessed using discrimination, calibration, and clinical usefulness. RESULTS: In total, 212 patients were enrolled. The SII and vFMR were closely related, and both independently predicted survival (P < 0.05). A predictive model was established based on the above biomarkers and included three subgroups: high-risk [both high SII (>828) and high vFMR (>1.1)], middle-risk (either high SII or high vFMR), and low-risk (neither high SII nor high vFMR). The 3-year OS (PFS) rates for low-, middle-, and high-risk patients were 90.5% (86.0%), 73.9% (58.4%), and 46.8% (36.1%), respectively (P < 0.05). This model demonstrated satisfactory predictive accuracy (area under the curve values for predicting 3-year OS and PFS were 0.704 and 0.718, respectively), good fit (Hosmer-Lemeshow tests: P > 0.05), and clinical usefulness. CONCLUSION: Systemic inflammatory markers combined with body composition parameters could independently predict the prognosis of patients with LACC, highlighting the utilization of commonly collected indicators in decision-making processes. CLINICAL SIGNIFICANCE: The SII and vFMR, as well as their composite indices, were promising prognostic factors in patients with LACC who received definitive CCRT. Future studies are needed to explore novel therapies to improve the outcomes in high-risk patients.

8.
J Med Virol ; 96(6): e29722, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38837255

RESUMO

Debates surrounding the efficacy of influenza vaccination for survival benefits persist, and there is a lack of data regarding its duration of protection. A self-controlled case series (SCCS) and a 1:4 matched case-control study were conducted using the National Health Interview Survey (NHIS) and public-use mortality data from 2005 to 2018 in the United States. The SCCS study identified participants who received influenza vaccination within 12 months before the survey and subsequently died within 1 year of postvaccination. The matched case-control study paired participants who died during the influenza season at the time of survey with four survivors. Among 1167 participants in the SCCS study, there was a 46% reduction in all-cause mortality and a 43% reduction in cardiovascular mortality within 29-196 days of postvaccination. The greatest protection was observed during days 29-56 (all-cause mortality: RI: 0.19; 95% CI: 0.12-0.29; cardiovascular mortality: RI: 0.28; 95% CI: 0.14-0.56). Among 626 cases and 2504 controls included in the matched case-control study, influenza vaccination was associated with a reduction in all-cause mortality (OR: 0.74, 95% CI: 0.60-0.92) and cardiovascular mortality (OR: 0.64, 95% CI: 0.44-0.93) during the influenza season. This study highlights the importance of influenza vaccination in reducing the risks of all-cause and cardiovascular mortality, with effects lasting for approximately 6 months.


Assuntos
Doenças Cardiovasculares , Vacinas contra Influenza , Influenza Humana , Vacinação , Humanos , Estudos de Casos e Controles , Vacinas contra Influenza/administração & dosagem , Masculino , Feminino , Influenza Humana/mortalidade , Influenza Humana/prevenção & controle , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Pessoa de Meia-Idade , Idoso , Vacinação/estatística & dados numéricos , Adulto , Estados Unidos/epidemiologia , Idoso de 80 Anos ou mais , Adulto Jovem
9.
Nat Commun ; 15(1): 4688, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824144

RESUMO

Ultrasmall copper nanoclusters have recently emerged as promising photocatalysts for organic synthesis, owing to their exceptional light absorption ability and large surface areas for efficient interactions with substrates. Despite significant advances in cluster-based visible-light photocatalysis, the types of organic transformations that copper nanoclusters can catalyze remain limited to date. Herein, we report a structurally well-defined anionic Cu40 nanocluster that emits in the second near-infrared region (NIR-II, 1000-1700 nm) after photoexcitation and can conduct single-electron transfer with fluoroalkyl iodides without the need for external ligand activation. This photoredox-active copper nanocluster efficiently catalyzes the three-component radical couplings of alkenes, fluoroalkyl iodides, and trimethylsilyl cyanide under blue-LED irradiation at room temperature. A variety of fluorine-containing electrophiles and a cyanide nucleophile can be added onto an array of alkenes, including styrenes and aliphatic olefins. Our current work demonstrates the viability of using readily accessible metal nanoclusters to establish photocatalytic systems with a high degree of practicality and reaction complexity.

10.
J Affect Disord ; 360: 297-304, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38823589

RESUMO

BACKGROUND AND AIM: The association between the Triglyceride-glucose (TyG) index and depression has been observed, yet its confirmation within peri- and postmenopausal demographics remains elusive. Consequently, the principal aim of this investigation is to explore the nexus between TyG-related indicators and depressive symptoms among pre- and postmenopausal women. METHODS: The data utilized in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) conducted from 2013 to 2016. The patients were divided into three groups based on TyG, Triglyceride-Glucose-Body Mass Index (TyG-BMI), Triglyceride-Glucose-Waist Circumference (TyG-WC), and Triglyceride-Glucose-Waist-to-Height Ratio (TyG-WHtR): Q1 (1st quintile), Q2 (2nd quintile), and Q3 (3rd quintile). Further exploration of the differences between these groups was conducted. Employing logistic regression, stratified analysis, restricted cubic splines, and subgroup analyses, we scrutinized the correlation between TyG-related indicators and depressive symptoms in both premenopausal and postmenopausal women. Furthermore, sensitivity analyses were conducted to assess the durability and uniformity of this relationship. RESULTS: In premenopausal women, there was a consistent independent positive correlation between TyG-BMI, TyG-WC, and TyG-WHtR with depressive symptoms across all three models, while TyG itself did not show a significant association. In Models 1 and 2, TyG-BMI exhibited a higher odds ratio (OR) value than the other two indicators [Model 1, Q3 OR (95 % confidence interval, CI) = 3.37 (1.91-5.94); Model 2, Q3 OR (95 % CI) = 3.03 (1.67-5.52)]. In Models 3, TyG-WHtR demonstrates a more significant association with depressive symptoms [Model 3, Q3 OR (95 % CI) = 2.85 (1.55-5.27)]. This correlation does not manifest in menopausal women. CONCLUSIONS: In premenopausal women, TyG-BMI, TyG-WC, and TyG-WHtR exhibited a positive and linear relationship with depressive symptoms. Furthermore, the analysis revealed that the combined measures of TyG-BMI, TyG-WC, and TyG-WHtR offered greater precision and sensitivity in assessing this association compared to TyG alone.

11.
Front Immunol ; 15: 1281940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835779

RESUMO

Background: The emergence of immunotherapy has changed the treatment modality for melanoma and prolonged the survival of many patients. However, a handful of patients remain unresponsive to immunotherapy and effective tools for early identification of this patient population are still lacking. Researchers have developed machine learning algorithms for predicting immunotherapy response in melanoma, but their predictive accuracy has been inconsistent. Therefore, the present systematic review and meta-analysis was performed to comprehensively evaluate the predictive accuracy of machine learning in melanoma response to immunotherapy. Methods: Relevant studies were searched in PubMed, Web of Sciences, Cochrane Library, and Embase from their inception to July 30, 2022. The risk of bias and applicability of the included studies were assessed using the Prediction Model Risk of Bias Assessment Tool (PROBAST). Meta-analysis was performed on R4.2.0. Results: A total of 36 studies consisting of 30 cohort studies and 6 case-control studies were included. These studies were mainly published between 2019 and 2022 and encompassed 75 models. The outcome measures of this study were progression-free survival (PFS), overall survival (OS), and treatment response. The pooled c-index was 0.728 (95%CI: 0.629-0.828) for PFS in the training set, 0.760 (95%CI: 0.728-0.792) and 0.819 (95%CI: 0.757-0.880) for treatment response in the training and validation sets, respectively, and 0.746 (95%CI: 0.721-0.771) and 0.700 (95%CI: 0.677-0.724) for OS in the training and validation sets, respectively. Conclusion: Machine learning has considerable predictive accuracy in melanoma immunotherapy response and prognosis, especially in the former. However, due to the lack of external validation and the scarcity of certain types of models, further studies are warranted.


Assuntos
Imunoterapia , Aprendizado de Máquina , Melanoma , Melanoma/terapia , Melanoma/imunologia , Melanoma/mortalidade , Humanos , Imunoterapia/métodos , Prognóstico , Resultado do Tratamento
12.
Virus Evol ; 10(1): veae024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827419

RESUMO

Venom is known as the source of natural antimicrobial products. Previous studies have largely focused on the expression of venom-related genes and the biochemical components of venom. With the advent of metagenomic sequencing, many more microorganisms, especially viruses, have been identified in highly diverse environments. Herein, we investigated the RNA virome in the venom-related microenvironment through analysis of a large volume of venom-related RNA-sequencing data mined from public databases. From this, we identified viral sequences belonging to thirty-six different viruses, of which twenty-two were classified as 'novel' as they exhibited less than 90 per cent amino acid identity to known viruses in the RNA-dependent RNA polymerase. Most of these novel viruses possessed genome structures similar to their closest relatives, with specific alterations in some cases. Phylogenetic analyses revealed that these viruses belonged to at least twenty-two viral families or unclassified groups, some of which were highly divergent from known taxa. Although further analysis failed to find venom-specific viruses, some viruses seemingly had much higher abundance in the venom-related microenvironment than in other tissues. In sum, our study provides insights into the RNA virome of the venom-related microenvironment from diverse animal phyla.

13.
J Clin Oncol ; : JCO2401001, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857463

RESUMO

PURPOSE: Phase 3 studies of intravenous amivantamab demonstrated efficacy across EGFR-mutated advanced non-small cell lung cancer (NSCLC). A subcutaneous formulation could improve tolerability and reduce administration time while maintaining efficacy. PATIENTS AND METHODS: Patients with EGFR-mutated advanced NSCLC who progressed following osimertinib and platinum-based chemotherapy were randomized 1:1 to receive subcutaneous or intravenous amivantamab, both combined with lazertinib. Co-primary pharmacokinetic noninferiority endpoints were trough concentrations (Ctrough; on cycle-2-day-1 or cycle-4-day-1) and cycle-2 area under the curve (AUCD1-D15). Key secondary endpoints were objective response rate (ORR) and progression-free survival (PFS). Overall survival (OS) was a predefined exploratory endpoint. RESULTS: Overall, 418 patients underwent randomization (subcutaneous group, n=206; intravenous group, n=212). Geometric mean ratios of Ctrough for subcutaneous to intravenous amivantamab were 1.15 (90% CI, 1.04-1.26) at cycle-2-day-1 and 1.42 (90% CI, 1.27-1.61) at cycle-4-day-1; the cycle-2 AUCD1-D15 was 1.03 (90% CI, 0.98-1.09). ORR was 30% in the subcutaneous and 33% in the intravenous group; median PFS was 6.1 and 4.3 months, respectively. OS was significantly longer in the subcutaneous versus intravenous group (hazard ratio for death, 0.62; 95% CI, 0.42-0.92; nominal P=0.02). Fewer patients in the subcutaneous group experienced infusion-related reactions (13% versus 66%) and venous thromboembolism (9% versus 14%) versus the intravenous group. Median administration time for first infusion was reduced to 4.8 minutes (range, 0-18) for subcutaneous amivantamab from 5 hours (range, 0.2-9.9) for intravenous amivantamab. During cycle-1-day-1, 85% and 52% of patients in the subcutaneous and intravenous groups, respectively, considered treatment convenient; end-of-treatment rates were 85% and 35%, respectively. CONCLUSION: Subcutaneous amivantamab-lazertinib demonstrated noninferiority to intravenous amivantamab-lazertinib, offering a consistent safety profile with reduced infusion-related reactions, increased convenience, and prolonged survival.

14.
Reprod Sci ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858331

RESUMO

Mono-butyl phthalate (MBP), the metabolite of dibutyl phthalate (DBP), is the most abundant phthalate metabolite found in Chinese women. Extracellular vesicles (EVs) are nanoscale lipid bilayer particles produced by extensive kinds of cells, serving a key role in intercellular communication. Extracellular vesicle miRNAs (EV-miRNAs) in follicular fluid (FF) have been evidenced to be associated with female reproductive health. The objective of this study was to investigate the associations of EV-miRNAs expressed profile with DBP exposure in FF of female participants and expose its potential mechanism in impaired oocyte development. Based on participants' FF MBP concentrations and fertilization status, we compared the miRNA expression between the FF-EVs of group A (high DBP exposure and impaired fertilization) and group B (low DBP exposure and normal fertilization). Compared with group B, miR-1246, miR-3679-5p, miR-423-5p, miR-5585-3p, miR-116-5p, miR-172-5p were upregulated, while miR-34b-3p was downregulated in group A. Target genes of the differently expressed miRNAs were predicted, and the functional analysis was performed. Furthermore, we exposed human ovarian granulosa tumor cell line (KGN) to MBP (4ug/L) to isolate the EVs from the culture medium and validated the expression levels of different miRNAs. We found that MBP exposure was significantly associated with increased levels of miR-116-5p (P = 0.01). In addition, we demonstrated that the most different miRNA, miR-116-5p regulated oocyte fertilization by inhibiting FOXO3a. Our findings suggested that EV-miRNAs in the FF might mediate MBP toxicity in oocytes.

15.
Clin Exp Rheumatol ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38855957

RESUMO

OBJECTIVES: To investigate the correlation between innate lymphoid cell (ILC) subsets with T-helper (Th) cells and to explore the effect of ILCs on T cells in rheumatoid arthritis (RA). METHODS: We analysed the frequencies of ILC subsets in RA patients with varying disease activity and their correlation with Th cell subsets. We further investigated this correlation in various organs of collagen-induced arthritis (CIA) mice. The effects of ILCs on CD4+ T cells were determined by in vitro cell co-culture experiments. RESULTS: ILCs were less frequent in RA patients than in healthy controls, with higher levels of group 3 ILCs (ILC3s) in RA (p<0.05). ILC3s correlated positively with Th1 and Th17 cells in RA peripheral blood (p<0.05). In the peripheral blood, spleen, and lymph nodes of CIA, ILC3s decreased and then increased during arthritis progression. ILC3s correlated positively with Th1 and Th17 cells in the spleen and lymph nodes of CIA (p<0.05). NKp46+ ILC3s in the spleen positively correlated with Th1 and Th17 cells (p<0.05). Under Th17 cell differentiation conditions, co-culturing CIA-derived ILC3s directly with naive CD4+ T cells promoted Th17 differentiation and increased IL-17 secretion. However, co-culturing through a transwell insert impeded Th17 differentiation without affecting IL-17 secretion. CONCLUSIONS: ILC3s positively correlated with Th1 and Th17 cells in RA. In CIA, the frequencies of ILC3s changed with disease development and showed a positive correlation with Th1 and Th17 cells. ILC3s may facilitate the differentiation of Th17 cells through direct cell-cell contact.

16.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): 1044-1058, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856416

RESUMO

The performance analysis of a free space optical (FSO) communication system in the presence of random jamming is presented over a Málaga (M) distributed channel model with pointing errors and atmospheric attenuation. Firstly, the probability density function expressions of the transmission channel, signal-to-jamming ratio, and signal-to-noise ratio are derived. Then, considering the probability of the jammer and Gaussian white noise, the closed-form expressions for the ergodic channel capacity, outage probability, and average bit error rate are derived. Moreover, asymptotic expressions for the aforementioned performance metrics are also derived to ascertain the diversity gain of the system. Extensive Monte Carlo simulations are performed to demonstrate the credibility of this theoretical analysis. Results indicate that the adverse impact of random jamming is higher than that of Gaussian noise for the FSO communication system. Besides, this observation highlights the pulsating nature of the jamming effect, showcasing that within high signal-to-jamming ratio regions, a low probability jammer exerts the most significant impact on the FSO system.

18.
Abdom Radiol (NY) ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849537

RESUMO

OBJECTIVE: Gastrointestinal stromal tumors (GISTs) are difficult to identify the risk level accurately without surgical pathological confirmation. The purpose of our study was to propose a noninvasive prediction method for predicting the malignant potential of GISTs preoperatively by using contrast-enhanced ultrasound (CEUS) with gastric distention. METHODS: We reviewed 47 GISTs who underwent CEUS from April 2017 to August 2023 retrospectively, all the lesions were certificated by pathology after surgery. The age of the patient, size of the lesion, shape, necrosis, calcification in the lesion, perfusion parameters including arrival time (AT), peak intensity (PI), time to peak (TTP), and area under the curve (AUC) of the lesion and surrounding normal tissue were analyzed. Logistic regression analyses were performed. Of the 47 GISTs, 26 were high-risk and 21 low-risk tumors respectively. RESULTS: Compared with low-risk GISTs, high-risk GIST had faster AT (7.7s vs. 11.5s, p < 0.05), higher PI (15.2dB vs. 12.5dB, p < 0.05), and larger size (4.4 cm vs. 2.2 cm, p < 0.001). In multivariate logistic regression, AT, PI, and size were significant features. The corresponding regression equation In (p/(1-p)=-5.9 + 4.5 size + 4.6 PI + 4.0 AT). CONCLUSION: The size, AT, and PI of the GISTs on CEUS can be used as parameters for a noninvasive risk level prediction model of GISTs. This model may help identify the different risk levels of GISTs before surgery.

19.
Antiviral Res ; : 105919, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851592

RESUMO

Bacillus spp. has been considered a promising source for identifying new antimicrobial substances, including anti-viral candidates. Here, we successfully isolated a number of bacteria strains from aged dry citrus peel (Chenpi). Of note, the culture supernatant of a new isolate named Bacillus subtilis LjM2 demonstrated strong inhibition of influenza A virus (IAV) infection in multiple experimental systems in vitro and in vivo. In addition, the anti-viral effect of LjM2 was attributed to its direct lysis of viral particles. Further analysis showed that a protease which we named CPAVM1 isolated from the culture supernatant of LjM2 was the key component responsible for its anti-viral function. Importantly, the therapeutic effect of CPAVM1 was still significant when applied 12 hours after IAV infection of experimental mice. Moreover, we found that the CPAVM1 protease cleaved multiple IAV proteins via targeting basic amino acid Arg or Lys. Furthermore, this study reveals the molecular structure and catalytic mechanism of CPAVM1 protease. During catalysis, Tyr75, Tyr77, and Tyr102 are important active sites. Therefore, the present work identified a special protease CPAVM1 secreted by a new strain of Bacillus subtilis LjM2 against influenza A virus infection via direct cleavage of critical viral proteins, thus facilitates future biotechnological applications of Bacillus subtilis LjM2 and the protease CPAVM1.

20.
ACS Nano ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841753

RESUMO

Methanogenic archaea, characterized by their cell membrane lipid molecules consisting of isoprenoid chains linked to glycerol-1-phosphate via ether bonds, exhibit exceptional adaptability to extreme environments. However, this distinct lipid architecture also complicates the interactions between methanogenic archaea and nanoparticles. This study addresses this challenge by exploring the interaction and transformation of selenium nanoparticles (SeNPs) within archaeal Methanosarcina acetivorans C2A. We demonstrated that the effects of SeNPs are highly concentration-dependent, with chemical stimulation of cellular processes at lower SeNPs concentrations as well as oxidative stress and metabolic disruption at higher concentrations. Notably, we observed the formation of a protein corona on SeNPs, characterized by the selective adsorption of enzymes critical for methylotrophic methanogenesis and those involved in selenium methylation, suggesting potential alterations in protein function and metabolic pathways. Furthermore, the intracellular transformation of SeNPs into both inorganic and organic selenium species highlighted their bioavailability and dynamic transformation within archaea. These findings provide vital insights into the nano-bio interface in archaeal systems, contributing to our understanding of archaeal catalysis and its broader applications.

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