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1.
Hortic Res ; 11(5): uhae071, 2024 May.
Article in English | MEDLINE | ID: mdl-38725458

ABSTRACT

Chinese jujube (Ziziphus jujuba Mill.) is one of the most important deciduous tree fruits in China, with substantial economic and nutritional value. Jujube was domesticated from its wild progenitor, wild jujube (Z. jujuba var. spinosa), and both have high medicinal value. Here we report the 767.81- and 759.24-Mb haplotype-resolved assemblies of a dry-eating 'Junzao' jujube (JZ) and a wild jujube accession (SZ), using a combination of multiple sequencing strategies. Each assembly yielded two complete haplotype-resolved genomes at the telomere-to-telomere (T2T) level, and ~81.60 and 69.07 Mb of structural variations were found between the two haplotypes within JZ and SZ, respectively. Comparative genomic analysis revealed a large inversion on each of chromosomes 3 and 4 between JZ and SZ, and numerous genes were affected by structural variations, some of which were associated with starch and sucrose metabolism. A large-scale population analysis of 672 accessions revealed that wild jujube originated from the lower reaches of the Yellow River and was initially domesticated at local sites. It spread widely and was then independently domesticated at the Shanxi-Shaanxi Gorge of the middle Yellow River. In addition, we identified some new selection signals regions on genomes, which are involved in the tissue development, pollination, and other aspects of jujube tree morphology and fertilization domestication. In conclusion, our study provides high-quality reference genomes of jujube and wild jujube and new insights into the domestication history of jujube.

2.
bioRxiv ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38712254

ABSTRACT

Splicing factor mutations are common in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), but how they alter cellular functions is unclear. We show that the pathogenic SRSF2P95H/+ mutation disrupts the splicing of mitochondrial mRNAs, impairs mitochondrial complex I function, and robustly increases mitophagy. We also identified a mitochondrial surveillance mechanism by which mitochondrial dysfunction modifies splicing of the mitophagy activator PINK1 to remove a poison intron, increasing the stability and abundance of PINK1 mRNA and protein. SRSF2P95H-induced mitochondrial dysfunction increased PINK1 expression through this mechanism, which is essential for survival of SRSF2P95H/+ cells. Inhibition of splicing with a glycogen synthase kinase 3 inhibitor promoted retention of the poison intron, impairing mitophagy and activating apoptosis in SRSF2P95H/+ cells. These data reveal a homeostatic mechanism for sensing mitochondrial stress through PINK1 splicing and identify increased mitophagy as a disease marker and a therapeutic vulnerability in SRSF2P95H mutant MDS and AML.

3.
J Clin Invest ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38713535

ABSTRACT

Splicing factor mutations are common in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), but how they alter cellular functions is unclear. We show that the pathogenic SRSF2P95H/+ mutation disrupts the splicing of mitochondrial mRNAs, impairs mitochondrial complex I function, and robustly increases mitophagy. We also identified a mitochondrial surveillance mechanism by which mitochondrial dysfunction modifies splicing of the mitophagy activator PINK1 to remove a poison intron, increasing the stability and abundance of PINK1 mRNA and protein. SRSF2P95H-induced mitochondrial dysfunction increased PINK1 expression through this mechanism, which is essential for survival of SRSF2P95H/+ cells. Inhibition of splicing with a glycogen synthase kinase 3 inhibitor promoted retention of the poison intron, impairing mitophagy and activating apoptosis in SRSF2P95H/+ cells. These data reveal a homeostatic mechanism for sensing mitochondrial stress through PINK1 splicing and identify increased mitophagy as a disease marker and a therapeutic vulnerability in SRSF2P95H mutant MDS and AML.

4.
Ecotoxicol Environ Saf ; 278: 116439, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38728945

ABSTRACT

Nanoplastic contamination has been of intense concern by virtue of the potential threat to human and ecosystem health. Animal experiments have indicated that exposure to nanoplastics (NPs) can deposit in the liver and contribute to hepatic injury. To explore the mechanisms of hepatotoxicity induced by polystyrene-NPs (PS-NPs), mice and AML-12 hepatocytes were exposed to different dosages of 20 nm PS-NPs in this study. The results illustrated that in vitro and in vivo exposure to PS-NPs triggered excessive production of reactive oxygen species and repressed nuclear factor erythroid-derived 2-like 2 (NRF2) antioxidant pathway and its downstream antioxidase expression, thus leading to hepatic oxidative stress. Moreover, PS-NPs elevated the levels of NLRP3, IL-1ß and caspase-1 expression, along with an activation of NF-κB, suggesting that PS-NPs induced hepatocellular inflammatory injury. Nevertheless, the activaton of NRF2 signaling by tert-butylhydroquinone mitigated PS-NPs-caused oxidative stress and inflammation, and inbihited NLRP3 and caspase-1 expression. Conversely, the rescuing effect of NRF2 signal activation was dramatically supressed by treatment with NRF2 inhibitor brusatol. In summary, our results demonstrated that NRF2-NLRP3 pathway is involved in PS-NPs-aroused hepatotoxicity, and the activation of NRF2 signaling can protect against PS-NPs-evoked liver injury. These results provide novel insights into the hepatotoxicity elicited by NPs exposure.

5.
BMC Pulm Med ; 24(1): 223, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714933

ABSTRACT

BACKGROUND: Pulmonary fibromatosis (PF) is a specific variant of fibromatosis, which is rarely reported occurring in the lung. PF with HIPK2-YAP1 fusion was a novel entity. CASE PRESENTATION: In this report, a 66-year-old male with PF had been smoking over 40 years. Multiple cords and small nodules in both lungs had been detected in a health examination two years earlier at our hospital. But approximately twofold enlarged in the lingual segment of the upper lobe in the left lung were disclosed in this year. Immunohistochemical analysis demonstrated that the vimentin and ß-Catenin were positive in the largest nodule. After underwent a DNA/RNA panel next-generation sequencing (NGS), missense mutations and HIPK2-YAP1 fusion were found in this sample. Ultimately, the case diagnosis as PF with HIPK2-YAP1 fusion after multidisciplinary treatment. Currently, the patient is doing well and recurrence-free at 14 months post-surgery. CONCLUSIONS: It's difficult for patients with complex morphology to make accurate diagnosis solely based on morphology and immunohistochemistry. But molecular detection is an effective method for further determining pathological subtypes.


Subject(s)
Adaptor Proteins, Signal Transducing , Carrier Proteins , Lung Neoplasms , Protein Serine-Threonine Kinases , Transcription Factors , YAP-Signaling Proteins , Humans , Male , Transcription Factors/genetics , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Aged , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/diagnosis , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Mutation, Missense
6.
ChemSusChem ; : e202400543, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38691099

ABSTRACT

CO2 hydrogenation to methanol has emerged as a promising strategy for achieving carbon neutrality and mitigating global warming, in which the supported Pd/In2O3 catalysts are attracting great attention due to their high selectivity. Nonetheless, conventional impregnation methods induce strong metal-support interaction (SMSI) between Pd and In2O3, which leads to the excessive reduction of In2O3 and the formation of undesirable PdIn alloy in hydrogen-rich atmospheres. Herein, we innovatively synthesized Pd/In2O3 nanocatalysts by the electrostatic self-assembly process between surface-modified composite precursors with opposite charges. And the organic ligands concurrently serve as Pd nanoparticle protective agents. The resultant Pd/In2O3 nanocatalyst demonstrates the homogeneous distribution of Pd nanoparticles with controllable sizes on In2O3 supports and the limited formation of PdIn alloy. As a result, it exhibits superior selectivity and stability compared to the counterparts synthesized by the conventional impregnation procedure. Typically, it attains a maximum methanol space-time yield of 0.54 gMeOH h-1gcat-1 (300 °C, 3.5 MPa, 21,000 mL gcat-1 h-1). Notably, the correlation characterization results reveal the significant effect of small-size, highly dispersed Pd nanoparticles in mitigating MSI. These results provide an alternative strategy for synthesizing highly efficient Pd/In2O3 catalysts and offer a new insight into the strong metal-support interaction.

7.
Infect Agent Cancer ; 19(1): 21, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38693556

ABSTRACT

AIMS: This study compared the prevalences of metabolic syndrome and of cardiac or kidney comorbidities among patients with hepatocellular carcinoma (HCC) associated with metabolic dysfunction-related fatty liver disease (MAFLD), chronic infection with hepatitis B or C virus (HBV or HCV), or the combination of MAFLD and chronic HBV infection. METHODS: Medical records were retrospectively analyzed for patients with HCC who underwent hepatectomy between March 2013 and March 2023. Patients with HCC of different etiologies were compared in terms of their clinicodemographic characteristics and laboratory data before surgery. RESULTS: Of the 2422 patients, 1,822 (75.2%) were chronically infected with HBV without MAFLD and HCV, 415 (17.2%) had concurrent MAFLD and chronic HBV infection but no HCV infection, 121 (5.0%) had MAFLD without hepatitis virus infection, and 64 (2.6%) were chronically infected with HCV in the presence or absence of MAFLD and HBV infection. Compared to patients chronically infected with HBV without MAFLD and HCV, those with MAFLD but no hepatitis virus infection showed significantly lower prevalence of cirrhosis, ascites, portal hypertension, alpha-fetoprotein concentration ≥ 400 ng/mL, tumor size > 5 cm, multinodular tumors and microvascular invasion. Conversely, they showed significantly higher prevalence of metabolic syndrome, hypertension, type 2 diabetes, abdominal obesity, history of cardiovascular disease, T-wave alterations, hypertriglyceridemia and hyperuricemia, as well as higher risk of arteriosclerotic cardiovascular disease. Compared to patients with MAFLD but no hepatitis virus infection, those with concurrent MAFLD and chronic infection with HBV showed significantly higher prevalence of cirrhosis, ascites and portal hypertension, but significantly lower prevalence of hypertension and history of cardiovascular disease. Compared to patients with other etiologies, those chronically infected with HCV in the presence or absence of MAFLD and HBV infection, showed significantly higher prevalence of cirrhosis, portal hypertension, ascites, and esophagogastric varices. CONCLUSION: Patients with HCC associated with MAFLD tend to have a background of less severe liver disease than those with HCC of other etiologies, but they may be more likely to suffer metabolic syndrome or comorbidities affecting the heart or kidneys.

8.
Anal Chem ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748451

ABSTRACT

Unraveling bacterial identity through Raman scattering techniques has been persistently challenging due to homogeneously amplified Raman signals across a wide variety of bacterial molecules, predominantly protein- or nucleic acid-mediated. In this study, we present an approach involving the use of silver nanoparticles to completely and uniformly "mask" adsorption on the surface of bacterial molecules through sodium borohydride and sodium chloride. This approach enables the acquisition of enhanced surface-enhanced Raman scattering (SERS) signals from all components on the bacterial surface, facilitating rapid, specific, and label-free bacterial identification. For the first time, we have characterized the identity of a bacterium, including its DNA, metabolites, and cell walls, enabling the accurate differentiation of various bacterial strains, even within the same species. In addition, we embarked on an exploration of the origin and variability patterns of the main characteristic peaks of Gram-positive and Gram-negative bacteria. Significantly, the SERS peak ratio was found to determine the inflection point of accelerated bacterial death upon treatment with antimicrobials. We further applied this platform to identify 15 unique clinical antibiotic-resistant bacterial strains, including five Escherichia coli strains in human urine, a first for Raman technology. This work has profound implications for prompt and accurate identification of bacteria, particularly antibiotic-resistant strains, thereby significantly enhancing clinical diagnostics and antimicrobial treatment strategies.

9.
High Alt Med Biol ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38743636

ABSTRACT

Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, and Jian Huang. Nitric oxide ameliorates the effects of hypoxia in mice by regulating oxygen transport by hemoglobin. High Alt Med Biol. 00:00-00, 2024.-Hypoxia is a common pathological and physiological phenomenon in ischemia, cancer, and strenuous exercise. Nitric oxide (NO) acts as an endothelium-derived relaxing factor in hypoxic vasodilation and serves as an allosteric regulator of hemoglobin (Hb). However, the ultimate effects of NO on the hematological system in vivo remain unknown, especially in extreme environmental hypoxia. Whether NO regulation of the structure of Hb improves oxygen transport remains unclear. Hence, we examined whether NO altered the oxygen affinity of Hb (Hb-O2 affinity) to protect extremely hypoxic mice. Mice were exposed to severe hypoxia with various concentrations of NO, and the survival time, exercise capacity, and other physical indexes were recorded. The survival time was prolonged in the 5 ppm NO (6.09 ± 1.29 minutes) and 10 ppm NO (6.39 ± 1.58 minutes) groups compared with the 0 ppm group (4.98 ± 1.23 minutes). Hypoxia of the brain was relieved, and the exercise exhaustion time was prolonged when mice inhaled 20 ppm NO (24.70 ± 6.87 minutes vs. 20.23 ± 6.51 minutes). In addition, the differences in arterial oxygen saturation (SO2%) (49.64 ± 7.29% vs. 42.90 ± 4.30%) and arteriovenous SO2% difference (25.14 ± 8.95% vs. 18.10 ± 6.90%) obviously increased. In ex vivo experiments, the oxygen equilibrium curve (OEC) left shifted as P50 decreased from 43.77 ± 2.49 mmHg (0 ppm NO) to 40.97 ± 1.40 mmHg (100 ppm NO) and 38.36 ± 2.78 mmHg (200 ppm NO). Furthermore, the Bohr effect of Hb was enhanced by the introduction of 200 ppm NO (-0.72 ± 0.062 vs.-0.65 ± 0.051), possibly allowing Hb to more easily offload oxygen in tissue at lower pH. The crystal structure reveals a greater distance between Asp94ß-His146ß in nitrosyl -Hb(NO-Hb), NO-HbßCSO93, and S-NitrosoHb(SNO-Hb) compared to tense Hb(T-Hb, 3.7 Å, 4.3 Å, and 5.8 Å respectively, versus 3.5 Å for T-Hb). Moreover, hydrogen bonds were less likely to form, representing a key limitation of relaxed Hb (R-Hb). Upon NO interaction with Hb, hydrogen bonds and salt bridges were less favored, facilitating relaxation. We speculated that NO ameliorated the effects of hypoxia in mice by promoting erythrocyte oxygen loading in the lung and offloading in tissues.

10.
EBioMedicine ; 104: 105152, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38728838

ABSTRACT

BACKGROUND: The tumour stroma is associated with unfavourable prognosis in diverse solid tumours, but its prognostic and predictive value in bladder cancer (BCa) is unclear. METHODS: In this multicentre, retrospective study, we included 830 patients with BCa from six independent cohorts. Differences in overall survival (OS) and cancer-specific survival (CSS) were investigated between high-tumour stroma ratio (TSR) and low-TSR groups. Multi-omics analyses, including RNA sequencing, immunohistochemistry, and single-cell RNA sequencing, were performed to study stroma-immune interactions. TSR prediction models were developed based on pelvic CT scans, and the best performing model was selected based on receiver operator characteristic analysis. FINDINGS: Compared to low-TSR tumours, high-TSR tumours were significantly associated with worse OS (HR = 1.193, 95% CI: 1.046-1.361, P = 0.008) and CSS (HR = 1.337, 95% CI: 1.139-1.569, P < 0.001), and lower rate of pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). High-TSR tumours exhibited higher infiltration of immunosuppressive cells, including Tregs and tumour-associated neutrophils, while low-TSR tumours exhibited higher infiltration of immune-activating cells such as CD8+ Teff and XCR1+ dendritic cells. The TSR prediction model was developed by combining the intra-tumour and tumour base radiomics features, and showed good performance to predict high-TSR, as indicted by area under the curve of 0.871 (95% CI: 0.821-0.921), 0.821 (95% CI: 0.731-0.911), and 0.801 (95% CI: 0.737-0.865) in the training, internal validation, and external validation cohorts, respectively. In patients with low predicted TSR, 92.3% (12/13) achieved pCR, while only 35.3% (6/17) of patients with high predicted TSR achieved pCR. INTERPRETATION: The tumour stroma was found to be significantly associated with clinical outcomes in patients with BCa as a result of tumour stroma-immune interactions. The radiomics prediction model provided non-invasive evaluation of TSR and was able to predict pCR in patients receiving NAC for BCa. FUNDING: This work was supported by National Natural Science Foundation of China (Grant No. 82373254 and 81961128027), Guangdong Provincial Natural Science Foundation (Grant No. 2023A1515010258), Science and Technology Planning Project of Guangdong Province (Grant No. 2023B1212060013). Science and Technology Program of Guangzhou (SL2022A04J01754), Sun Yat-Sen Memorial Hospital Clinical Research 5010 Program (Grant No. SYS-5010Z-202401).

11.
Inorg Chem ; 2024 May 06.
Article in English | MEDLINE | ID: mdl-38711379

ABSTRACT

Two two-dimensional (2D) layered metal-organic frameworks (MOFs), namely, {[Yb(L)(H2O)2NO3]·2H2O}n (Yb-MOF) and [Er(L)(H2O)3Cl]n (Er-MOF) (H2L = 5-((6H-purin-6-yl)amino)isophthalic acid), were constructed by a solvothermal method and characterized. The catalytic performance study showed that the Yb-MOF could efficiently catalyze the oxidation of sulfides to sulfoxides under 15 W light-emitting diode (LED) blue light irradiation. Electron paramagnetic resonance spectroscopy and free-radical trapping experiments demonstrated that the photocatalytic reaction process involved •O2-, and the corresponding mechanism was proposed. Moreover, Er-MOF exhibited good catalytic efficiency and excellent substrate tolerance in the cycloaddition reaction of CO2, and the reaction conditions were mild. After 5 cycles, the catalytic activities of two MOFs did not significantly decrease, and the framework structures remained unchanged. Therefore, the Yb-MOF and Er-MOF were considered efficient and stable heterogeneous catalysts.

12.
Orthop Surg ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38715422

ABSTRACT

OBJECTIVE: Focal cervical kyphotic deformity (FCK) without neurologic compression is not uncommon in patients with cervical spondylotic myelopathy (CSM) who underwent anterior cervical decompression and fusion (ACDF) surgery. It remains unclear whether FCK at non-responsible levels needs to be treated simultaneously. This study aims to investigate whether FCK at non-responsible levels is the prognostic factor for CSM and elucidate the surgical indication for FCK. METHODS: Patients with CSM who underwent ACDF between January 2016 and April 2021 were included. Patients were divided into two groups according to the presence of FCK and two classifications according to global cervical sagittal alignment. Clinical outcomes were compared using Japanese Orthopaedic Association (JOA) scores and recovery rate (RR) of neurologic function. Univariate and multivariate analysis based on RR assessed the relationship between various possible prognostic factors and clinical outcomes. The receiver operating characteristic curve (ROC) was used to determine the optimal cutoff value of the focal Cobb angle to predict poor clinical outcomes. RESULTS: A total of 94 patients were included, 41 with FCK and 53 without. Overall, the RR of neurologic function was significantly lower in the FCK than in the non-FCK group. Further analysis showed that the RR difference between the two groups was only observed in hypo-lordosis classification (kyphotic and sigmoid alignment), but not in the lordosis classification. Multivariate analysis showed that the preoperative focal Cobb angle in the FCK level (OR = 0.42; 95% CI = 0.18-0.97) was independently associated with clinical outcomes in the hypo-lordosis classification. The optimal cutoff point of the preoperative focal kyphotic Cobb angle was calculated at 4.05°. CONCLUSION: For CSM with hypo-lordosis, FCK was a risk factor for poor postoperative outcomes. Surgeons may consider treating the FCK simultaneously if the focal kyphotic Cobb angle of FCK is greater than 4.05° and is accompanied by cervical global kyphotic or sigmoid deformity.

13.
Article in English | MEDLINE | ID: mdl-38694704

ABSTRACT

Purpose: The complicated pathogenesis and poor prognosis of breast cancer have become a major difficulty in medical research. This study aims to explore new lncRNA as prognostic markers for breast cancer and explore their roles and molecular mechanisms to lay a foundation for the treatment of cancer patients. Patients and Methods: The expression of LINC02418 and miR-766-5p in breast cancer tissues and cells was first identified using polymerase chain reaction, and Pearson was used to examine the correlation between the two. The cancer cells activities under different transfection conditions were detected using the Transwell assay and CCK8 assay. The correlation between LINC02418 and patient prognosis was analyzed using multifactor Cox regression and Kaplan-Meier. Results: It was shown that LINC02418 expression was upregulated in breast cancer tissues and cells. There are significant differences in lymph node metastasis and TNM stage between high and low LINC02418 expression groups. The higher the expression of LINC02418, the higher the mortality rate of breast cancer patients. miR-766-5p expression was downregulated and negatively correlated with LINC02418. There are binding sites between LINC02418 and miR-766-5p; Transfection with miR-766-5p inhibitor boosted LINC02418 luciferase activity, but transfection with miR-766-5p mimic decreased it. Knockdown of LINC02418 promoted miR-766-5p expression and inhibited cancer progression, which was alleviated to some extent by transfection with miR-766-5p inhibitors. Conclusion: LINC02418 has the potential to serve as a poor prognostic marker for breast cancer and plays a pro-oncogenic role by targeting miR-766-5p.

14.
Eur Urol Open Sci ; 64: 2-8, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38694878

ABSTRACT

Background and objective: Robot-assisted radical prostatectomy (RARP) is widely used because of the many advantages of a robotic approach. The da Vinci Si robot is one of the most commonly used surgical robot systems, but it may be associated with higher costs owing to the use of consumable surgical supplies. Our aim was to conduct a preliminary investigation of the capability of the MP1000 system for RARP. Methods: In this prospective, multicentre, single-blinded study, we randomly assigned 42 patients scheduled to undergo RARP between April and September 2021 to a da Vinci Si group (control) or an MP1000 group (intervention). Patients underwent RARP performed using the assigned robotic system and were followed up at 3-mo intervals. The primary outcome was the rate of conversion to open/laparoscopic surgery. Secondary outcomes were installation and operation times, intraoperative blood loss, postoperative surgical margin status, hospital stay, incontinence, complications, safety indicators, and surgeon ergonomics. Key findings and limitations: All procedures were successfully completed without conversion to open/laparascopic surgery or major complications. Secondary outcomes, including oncological and ergonomic indicators, did not differ significantly between the groups over the study period. One patient in the control group experienced dysuria (Clavien-Dindo grade 3). No patients had incontinence at 3 mo. A limitation of the study is the small sample size. Conclusions and clinical implications: RARP with the MP1000 system is feasible, safe, and effective in the management of localised prostate cancer. Patient summary: We assessed the effectiveness and safety of the new MP1000 robot system for robot-assisted removal of the prostate in comparison to the da Vinci Si robot. We found no difference in effectiveness or safety among 42 patients with prostate cancer who were assigned randomly to one of the two systems. We conclude that the MP1000 is a suitable robot for this surgery.

15.
bioRxiv ; 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38585726

ABSTRACT

Ca2+ signaling plays a key role in physiological processes such as memory formation and cardiac function. Ca2+/calmodulin-dependent protein kinase II (CaMKII) is the primary kinase that responds to Ca2+ inputs in these cells. There are four CaMKII paralogs in mammals which are alternatively spliced in the variable linker region to create upwards of 70 different variants. In this study, we systematically studied different linker regions and determined that the position of charged residues within the linker region modulates the Ca2+/CaM sensitivity of the holoenzyme. We present an X-ray crystal structure of full-length CaMKIIδ that shows a domain-swapped conformation of the subunits within the dodecameric holoenzyme. In this structure, the kinase domain of one subunit is docked onto the hub domain of a different subunit, providing an additional interface within the holoenzyme. Mutations at the equatorial and lateral interfaces revealed that the kinase-hub interaction dissociates as the hub-hub interfaces are disturbed, which led alterations in the stoichiometry of CaMKII holoenzyme and Ca2+/CaM sensitivity. Molecular dynamics simulations of linker-containing domain-swapped and non-domain-swapped CaMKIIs reveal that the domain-swapped configuration facilitates an interaction between the calmodulin binding domain and the variable linker region, such that dynamic electrostatic forces between charges on these segments can modulate the equilibrium between the compact and extended conformational states of the holoenzyme. Small angle X-ray scattering data confirms that a negatively charged linker CaMKII holoenzyme adopts a more compact conformation compared to a positively charged linker. These data support a model where patches of charged linker residues interact with the calmodulin binding domain to allosterically regulate sensitivity to Ca2+/CaM. Our findings provide a new framework for understanding CaMKII structure and allosteric regulation by the variable linker region in Ca2+-sensitive cells.

16.
Toxics ; 12(4)2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38668492

ABSTRACT

Due to their significant environmental impact, there has been a gradual restriction of the production and utilization of legacy per- and polyfluoroalkyl substances (PFAS), leading to continuous development and adoption of novel alternatives. To effectively identify the potential environmental risks from crop consumption, the levels of 25 PFAS, including fourteen perfluoroalkyl acids (PFAAs), two precursor substances and nine novel alternatives, in agricultural soils and edible parts of various crops around a fluoride industrial park (FIP) in Changshu city, China, were measured. The concentration of ΣPFAS in the edible parts of all crops ranged from 11.64 to 299.5 ng/g, with perfluorobutanoic acid (PFBA) being the dominant compound, accounting for an average of 71% of ΣPFAS. The precursor substance, N-methylperfluoro-octanesulfonamidoacetic acid (N-MeFOSAA), was detected in all crop samples. Different types of crops showed distinguishing accumulation profiles for the PFAS. Solanaceae and leafy vegetables showed higher levels of PFAS contamination, with the highest ΣPFAS concentrations reaching 190.91 and 175.29 ng/g, respectively. The highest ΣAlternative was detected in leafy vegetables at 15.21 ng/g. The levels of human exposure to PFAS through crop consumption for various aged groups were also evaluated. The maximum exposure to PFOA for urban toddlers reached 109.8% of the standard value set by the European Food Safety Authority (EFSA). In addition, short-chained PFAAs and novel alternatives may pose potential risks to human health via crop consumption.

18.
Nanomaterials (Basel) ; 14(7)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38607094

ABSTRACT

Chemical warfare agents (CWAs) refer to toxic chemical substances used in warfare. Recently, CWAs have been a critical threat for public safety due to their high toxicity. Metal-organic frameworks have exhibited great potential in protecting against CWAs due to their high crystallinity, stable structure, large specific surface area, high porosity, and adjustable structure. However, the metal clusters of most reported MOFs might be highly consumed when applied in CWA hydrolysis. Herein, we fabricated a two-dimensional piezoresponsive UiO-66-F4 and subjected it to CWA simulant dimethyl-4-nitrophenyl phosphate (DMNP) detoxification under sonic conditions. The results show that sonication can effectively enhance the removal performance under optimal conditions; the reaction rate constant k was upgraded 45% by sonication. Moreover, the first-principle calculation revealed that the band gap could be further widened with the application of mechanical stress, which was beneficial for the generation of 1O2, thus further upgrading the detoxification performance toward DMNP. This work demonstrated that mechanical vibration could be introduced to CWA protection, but promising applications are rarely reported.

19.
Adv Sci (Weinh) ; : e2401586, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38666496

ABSTRACT

The continued miniaturization of chips demands highly thermally conductive materials and effective thermal management strategies. Particularly, the high-field transport of the devices built with 2D materials is limited by self-heating. Here a systematic control of heat flow in single-side fluorinated graphene (FG) with varying degrees of fluorination is reported, revealing a superior room-temperature thermal conductivity as high as 128 W m-1 K-1. Monolayer graphene/FG lateral heterostructures with seamless junctions are approached for device fabrication. Efficient in-plane heat removal paths from graphene channel to side FG are created, contributing significant reduction of the channel peak temperature and improvement in the current-carrying capability and power density. Molecular dynamics simulations indicate that the interfacial thermal conductance of the heterostructure is facilitated by the high degree of overlap in the phonon vibrational spectra. The findings offer novel design insights for efficient heat dissipation in micro- and nanoelectronic devices.

20.
Pharmacol Res ; 203: 107164, 2024 May.
Article in English | MEDLINE | ID: mdl-38569981

ABSTRACT

The impact of mitochondrial dysfunction on the pathogenesis of cardiovascular disease is increasing. However, the precise underlying mechanism remains unclear. Mitochondria produce cellular energy through oxidative phosphorylation while regulating calcium homeostasis, cellular respiration, and the production of biosynthetic chemicals. Nevertheless, problems related to cardiac energy metabolism, defective mitochondrial proteins, mitophagy, and structural changes in mitochondrial membranes can cause cardiovascular diseases via mitochondrial dysfunction. Mitofilin is a critical inner mitochondrial membrane protein that maintains cristae structure and facilitates protein transport while linking the inner mitochondrial membrane, outer mitochondrial membrane, and mitochondrial DNA transcription. Researchers believe that mitofilin may be a therapeutic target for treating cardiovascular diseases, particularly cardiac mitochondrial dysfunctions. In this review, we highlight current findings regarding the role of mitofilin in the pathogenesis of cardiovascular diseases and potential therapeutic compounds targeting mitofilin.


Subject(s)
Cardiovascular Diseases , Mitochondrial Proteins , Muscle Proteins , Humans , Animals , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/drug therapy , Muscle Proteins/metabolism , Muscle Proteins/genetics , Mitochondrial Proteins/metabolism , Mitochondria, Heart/metabolism , Mitochondria, Heart/drug effects
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