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1.
Int J Nanomedicine ; 19: 6035-6055, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38911505

RESUMEN

Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental condition that affects social interaction and communication and can cause stereotypic behavior. Fullerenols, a type of carbon nanomaterial known for its neuroprotective properties, have not yet been studied for their potential in treating ASD. We aimed to investigate its role in improving autistic behaviors in BTBR T+Itpr3tf/J (BTBR) mice and its underlying mechanism, which could provide reliable clues for future ASD treatments. Methods: Our research involved treating C57BL/6J (C57) and BTBR mice with either 0.9% NaCl or fullerenols (10 mg/kg) daily for one week at seven weeks of age. We then conducted ASD-related behavioral tests in the eighth week and used RNA-seq to screen for vital pathways in the mouse hippocampus. Additionally, we used real-time quantitative PCR (RT-qPCR) to verify related pathway genes and evaluated the number of stem cells in the hippocampal dentate gyrus (DG) by Immunofluorescence staining. Results: Our findings revealed that fullerenols treatment significantly improved the related ASD-like behaviors of BTBR mice, manifested by enhanced social ability and improved cognitive deficits. Immunofluorescence results showed that fullerenols treatment increased the number of DCX+ and SOX2+/GFAP+ cells in the DG region of BTBR mice, indicating an expanded neural progenitor cell (NPC) pool of BTBR mice. RNA-seq analysis of the mouse hippocampus showed that VEGFA was involved in the rescued hippocampal neurogenesis by fullerenols treatment. Conclusion: In conclusion, our findings suggest that fullerenols treatment improves ASD-like behavior in BTBR mice by upregulating VEGFA, making nanoparticle- fullerenols a promising drug for ASD treatment.


Asunto(s)
Trastorno del Espectro Autista , Disfunción Cognitiva , Modelos Animales de Enfermedad , Proteína Doblecortina , Fulerenos , Ratones Endogámicos C57BL , Animales , Ratones , Fulerenos/farmacología , Fulerenos/química , Trastorno del Espectro Autista/tratamiento farmacológico , Disfunción Cognitiva/tratamiento farmacológico , Masculino , Conducta Social , Conducta Animal/efectos de los fármacos , Hipocampo/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/genética , Fármacos Neuroprotectores/farmacología , Neurogénesis/efectos de los fármacos , Trastorno Autístico/tratamiento farmacológico
2.
J Chem Inf Model ; 64(13): 5303-5316, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38921060

RESUMEN

The coexistence of amyloid-ß (Aß) and human islet amyloid polypeptide (hIAPP) in the brain and pancreas is associated with an increased risk of Alzheimer's disease (AD) and type 2 diabetes (T2D) due to their coaggregation and cross-seeding. Despite this, the molecular mechanisms underlying their interaction remain elusive. Here, we systematically investigated the cross-talk between Aß and hIAPP using atomistic discrete molecular dynamics (DMD) simulations. Our results revealed that the amyloidogenic core regions of both Aß (Aß10-21 and Aß30-41) and hIAPP (hIAPP8-20 and hIAPP22-29), driving their self-aggregation, also exhibited a strong tendency for cross-interaction. This propensity led to the formation of ß-sheet-rich heterocomplexes, including potentially toxic ß-barrel oligomers. The formation of Aß and hIAPP heteroaggregates did not impede the recruitment of additional peptides to grow into larger aggregates. Our cross-seeding simulations demonstrated that both Aß and hIAPP fibrils could mutually act as seeds, assisting each other's monomers in converting into ß-sheets at the exposed fibril elongation ends. The amyloidogenic core regions of Aß and hIAPP, in both oligomeric and fibrillar states, exhibited the ability to recruit isolated peptides, thereby extending the ß-sheet edges, with limited sensitivity to the amino acid sequence. These findings suggest that targeting these regions by capping them with amyloid-resistant peptide drugs may hold potential as a therapeutic approach for addressing AD, T2D, and their copathologies.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Diabetes Mellitus Tipo 2 , Polipéptido Amiloide de los Islotes Pancreáticos , Simulación de Dinámica Molecular , Enfermedad de Alzheimer/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Polipéptido Amiloide de los Islotes Pancreáticos/química , Polipéptido Amiloide de los Islotes Pancreáticos/metabolismo , Humanos , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/química , Agregado de Proteínas
3.
Clin Case Rep ; 12(6): e9031, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38883224

RESUMEN

Key Clinical Message: Acute chest pain can be the first manifestation of multiple endocrine neoplasia type 1(MEN1)-associated thymic neuroendocrine neoplasms (NEN). Comprehensive treatment may be an effective strategy for MEN1-associated NEN. Abstract: Multiple endocrine neoplasia type 1(MEN1)-associated thymic neuroendocrine neoplasms (NEN) is caused by the mutation of tumor suppressor MEN1 gene. Patients with MEN1-associated NEN initially presenting with acute chest pain are very rare. In the manuscript, we reported a case of a 45-year-old man who developed MEN1-associated NEN with acute chest pain as initial symptom. Thoracoscopic thymotomy was performed and thymic NEN was successfully removed. Genetic test showed a germline mutation of MEN1 gene in this patient. Immunohistochemical staining exhibited Syn(+), CgA(+), INSM1(+), CD56(+) and Ki67-positive cells (2%) in MEN1-associated NEN. Further evaluation unveiled MEN1-associated benign tumors including digestive NEN and pituitary gland adenoma. The 99mTc-HYNIC-TOC scintigraphy showed that focally increased radioactivity in the mid-upper abdomen. This patient was administered with 50Gy/25F of radiation dose to treat the postoperative lesions. Subsequently, sandostatin LAR (30 mg per week) was used as systemic therapy. He had no recurrence or metastasis for 6-month follow-up. Thus, acute chest pain can be the first manifestation of MEN1-associated NEN, and comprehensive treatment including surgery, radiation and systemic treatment may be an effective strategy for MEN1-associated NEN.

4.
Microsc Res Tech ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856633

RESUMEN

Rosa laxa Retz. is an unexplored Rosaceae plant in Xinjiang, China, and its flower is traditionally used in Kazak to treat the common cold, fever, and epileptic seizures and lessen the effects of aging. In the present study, the pharmacognostic profiles, physicochemical properties, phytochemical characteristics, and in vitro antioxidant potency of Rosa laxa Retz. flos (RLF) were presented. In the pharmacognostic evaluation of RLF, organoleptic characteristics, internal structures, and powder information were observed, and physicochemical parameters, including moisture content, ash, pH value, swelling degree, and extractives were examined. The quantitative analysis of the chemical composition of four different polar extracts of RLF showed that the aqueous part had the highest total triterpene acid, flavonoid, and polyphenol content (4.50 ± 0.04 mg/g, 50.56 ± 0.03 mg/g, and 60.20 ± 0.09 mg/g, respectively). A high-performance liquid chromatography (HPLC)-diode array detector (DAD) method was established and the contents of gallic acid, ellagic acid, astragalin, and tiliroside in RLF were determined simultaneously. In the set concentration range, the linear relationship among the four components was good (r > 0.999), the average recoveries were 97.36%-100.54%. The contents of gallic acid, ellagic acid, astragalin, and tiliroside in RLF samples were (9.46 ± 2.31) mg/g, (10.60 ±0.75) mg/g, (1.13 ± 2.50) mg/g, and (1.11 ± 2.65) mg/g, respectively. The types of its secondary metabolites were determined by fluorescence, color reaction by chemical solvent method, and ultraviolet-visible (UV-Vis) spectroscopy. The functional groups of its secondary metabolites were determined by Fourier transform infrared (FTIR) spectroscopy. Results showed that RLF contains a variety of secondary metabolic products, including flavonoids, phenolic acid, glycoside, and organic acid. TLC identification showed it contains ursolic acid, ß-sitosterol, tiliroside, astragalin, isoquercitrin, kaempferol-3-O-rutinoside, gallic acid, and ellagic acid. The in vitro antioxidant activity of different polar parts of RLF was investigated by DPPH, ABTS, and reduction performance experiments. The aqueous extract had the strongest antioxidant capacity, consistent with the high content of triterpene acids, flavonoids, and polyphenolic compounds. These findings will provide critical information for the study of quality standards and medicinal value of RLF and its extracts, justify its usage in traditional medicinal systems, and encourage the use of this plant in disease prevention and treatment. Its phytochemical composition and pharmacological studies need to be explored in future. RESEARCH HIGHLIGHTS: Optical microscope and scanning electron microscope (SEM) were used to observe the morphology, and microstructure of Rosa laxa Retz. flos (RLF). The physicochemical properties, fluorescence and phytochemical composition of four different polar extracts of RLF were analyzed by UV-Vis and FTIR. Determination of total triterpenic acid, total flavonoids, and total polyphenols in four different polar extracts of RLF by UV spectrophotometry. A high-performance liquid chromatography (HPLC)-diode array detector (DAD) method was established and the contents of gallic acid, ellagic acid, astragalin, and tiliroside in RLF were determined simultaneously. TLC confirmed that RLF contains ursolic acid, ß-sitosterol, tiliroside, astragalin, isoquercitrin, kaempferol 3-rutinoside, gallic acid, and ellagic acid. The in vitro antioxidant activity of RLF was studied by DPPH, ABTS, and reducing ability experiments.

5.
Plant Biotechnol J ; 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38923265

RESUMEN

The development of plant virus-based expression systems has expanded rapidly owing to their potential applications in gene functional and disease resistance research, and industrial production of pharmaceutical proteins. However, the low yield of certain proteins, especially high-molecular-mass proteins, restricts the production scale. In this study, we observed that the tobacco mosaic virus (TMV)-mediated expression of a foreign protein was correlated with the amount of the movement protein (MP) and developed a TMV-derived pAT-transMP vector system incorporating trans-complementation expression of MP. The system is capable of efficient expression of exogenous proteins, in particular those with a high molecular mass, and enables simultaneous expression of two target molecules. Furthermore, viral expression of competent CRISPR-Cas9 protein and construction of CRISPR-Cas9-mediated gene-editing system in a single pAT-transMP construct was achieved. The results demonstrated a novel role for TMV-MP in enhancing the accumulation of a foreign protein produced from the viral vector or a binary expression system. Further investigation of the mechanism underlying this role will be beneficial for optimization of plant viral vectors with broad applications.

6.
J Immunother Cancer ; 12(6)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38925680

RESUMEN

BACKGROUND: The majority of anti-programmed cell-death 1 (PD-1) monoclonal antibodies (mAbs) use S228P mutation IgG4 as the structural basis to avoid the activation of immune cells or complement. However, little attention has been paid to the Fc-Fc interactions between IgG4 and other IgG Fc fragments that could result in adverse effects. Fc-null IgG1 framework is a potential safer alternative to avoid the undesirable Fc-Fc interactions and Fc receptor binding derived effects observed with IgG4. This study provides a comprehensive evaluation of anti-PD-1 mAbs of these two frameworks. METHODS: Trastuzumab and rituximab (both IgG1), wildtype IgG1 and IgG4 were immobilized on nitrocellulose membranes, coated to microplates and biosensor chips, and bound to tumor cells as targets for Fc-Fc interactions. Wildtype IgG1 and IgG4, anti-PD-1 mAb nivolumab (IgG4 S228P), penpulimab (Fc-null IgG1), and tislelizumab (Fc-null IgG4 S228P-R409K) were assessed for their binding reactions to the immobilized IgG proteins and quantitative kinetic data were obtained. To evaluate the effects of the two anti-PD-1 mAbs on immune responses mediated by trastuzumab and rituximab in the context of combination therapy, we employed classic immune models for antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, and complement dependent cytotoxicity. Tumor-bearing mouse models, both wildtype and humanized, were used for in vivo investigation. Furthermore, we also examined the effects of IgG1 and IgG4 on diverse immune cell populations RESULTS: Experiments demonstrated that wildtype IgG4 and nivolumab bound to immobilized IgG through Fc-Fc interactions, diminishing antibody-dependent cell-mediated cytotoxicity and phagocytosis reactions. Quantitative analysis of kinetic parameters suggests that nivolumab and wildtype IgG4 exhibit comparable binding affinities to immobilized IgG1 in both non-denatured and denatured states. IgG4 exerted inhibitory effects on various immune cell types. Wildtype IgG4 and nivolumab both promoted tumor growth in wildtype mouse models. Conversely, wildtype IgG1, penpulimab, and tislelizumab did not show similar adverse effects. CONCLUSIONS: Fc-null IgG1 represents a safer choice for anti-PD-1 immunotherapies by avoiding both the adverse Fc-Fc interactions and Fc-related immune inhibitory effects of IgG4. Fc-null IgG4 S228P-R409K and Fc-null IgG1 displayed similar structural properties and benefits. This study contributes to the understanding of immunotherapy resistance and the advancement of safer immune therapies for cancer.


Asunto(s)
Inmunoglobulina G , Inmunoterapia , Inmunoglobulina G/inmunología , Animales , Ratones , Humanos , Inmunoterapia/métodos , Fragmentos Fc de Inmunoglobulinas/farmacología , Femenino , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo
7.
Heliyon ; 10(9): e30085, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38711659

RESUMEN

Clarifying load transfer mechanism and the influence of the widening of a newly-built railway is the premise for the construction of adjacent project in loess region. This paper uses monitoring datas obtained from three sections in different stages to analyze the distribution laws of load exert on piles and soil between piles, investigates the variation laws of filling height on the earth pressure at different excavation steps and elucidates the influence of the filling height of newly built subgrade on the existing subgrade. In addition, a fitting formula y = a(1-e-bx) + cx is proposed to describe the relationship between the ratio of the additional displacement to the filling height, which is applicable for similar projects.

8.
Gynecol Endocrinol ; 40(1): 2352133, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38749017

RESUMEN

OBJECTIVES: Progestin-primed ovarian stimulation (PPOS) is an efficient controlled ovarian stimulation (COS) method. The study explored the pregnancy outcomes between PPOS and antagonist ovarian stimulation protocol (GnRH-ant) in infertile patients with poor ovarian response (POR). METHODS: This retrospective study included patients with POR who underwent COS at the Reproductive Medical Center of Shanxi Maternal and Child Health Hospital from January 2021 to April 2022. The cycles were grouped as the GnRH-ant group and the PPOS group. The primary outcome was the clinical pregnancy rate; the secondary outcomes included the biochemical pregnancy abortion rate and live birth rate. RESULTS: Frozen embryo transfer was used in all cycles in this study. The cycles were divided into the GnRH-ant (n = 236 cycles) and PPOS (n = 273 cycles) groups. Age, BMI, type of infertility, infertility duration, FSH, LH, PRL, E2, T, P, and the number of cycles in the hospital were similar between the two groups (all p > 0.05). No statistically significant differences were observed in the clinical pregnancy rate (primary outcome, 32.71% vs. 43.90%, p = 0.082), total Gn dose, total Gn days, ART mode (IVF or ICSI), AFC, MII follicles, 2PN embryos, fertility, cycle cancelation rate, biochemical pregnancy rate, abortion rate, or live birth rate between the two groups (all p > 0.05). The PPOS group exhibited a higher rate of high-quality embryos than the GnRH-ant group (50.12% vs. 42.90%, p = 0.045). CONCLUSIONS: The PPOS protocol was comparable to the GnRH-ant protocol regarding induction parameters and cycle cancelation, biochemical pregnancy, clinical pregnancy, and abortion rates but might be associated with a higher proportion of high-quality embryos.


Asunto(s)
Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , Resultado del Embarazo , Índice de Embarazo , Progestinas , Humanos , Femenino , Embarazo , Inducción de la Ovulación/métodos , Estudios Retrospectivos , Adulto , Progestinas/administración & dosificación , Progestinas/uso terapéutico , Resultado del Embarazo/epidemiología , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Infertilidad Femenina/terapia , Transferencia de Embrión/métodos , Antagonistas de Hormonas/uso terapéutico , Antagonistas de Hormonas/administración & dosificación
9.
Chem Sci ; 15(21): 8170-8180, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38817585

RESUMEN

Aqueous electrolytes subjected to angstrom-scale confinement have recently attracted increasing interest because of their distinctive structural and transport properties, as well as their promising applicability in bioinspired nanofluidic iontronics and ion batteries. Here, we performed microsecond-scale molecular dynamics simulations, which provided evidence of nonlinear ionic conductance under an external lateral electric field due to the self-assembly of cations and anions with diverse polyelectrolyte morphologies (e.g., extremely large ion clusters) in aqueous solutions within angstrom-scale slits. Specifically, we found that the cations and anions of Li2SO4 and CaSO4 formed chain-like polyelectrolyte structures, whereas those of Na2SO4 and MgSO4 predominantly formed a monolayer of hydrated salt. Additionally, the cations and anions of K2SO4 assembled into a hexagonal anhydrous ionic crystal. These ion-dependent diverse polyelectrolyte morphologies stemmed from the enhanced Coulomb interactions, weakened hydration and steric constraints within the angstrom-scale slits. More importantly, once the monolayer hydrated salt or ionic crystal structure was formed, the field-induced ion current exhibited an intriguing gating effect at a low field strength. This abnormal ion transport was attributed to the concerted movement of cations and anions within the solid polyelectrolytes, leading to the suppression of ion currents. When the electric field exceeded a critical strength, however, the ion current surged rapidly due to the dissolution of many cations and anions within a few nanoseconds in the aqueous solution.

10.
Cancer Sci ; 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38613253

RESUMEN

Peripheral T-cell lymphoma (PTCL) is a highly aggressive type of non-Hodgkin's lymphoma with a poor prognosis. Pyroptosis is a newly discovered procedural cell death mode, which has been implicated to occur in both tumor cells and immune cells. However, the occurrence and effect of pyroptosis on PTCL remain unclear. Here, we found that pyroptosis occurred in interstitial macrophages of PTCL rather than in tumor cells. In clinical specimens, macrophage pyroptosis was associated with a poor prognosis of PTCL. In vitro experiments and gene sequencing results showed that pyroptotic macrophages could upregulate the expression of TLR4 through secreting inflammatory cytokines IL-18. Upregulated TLR4 activated its downstream NF-κB anti-apoptotic signaling pathway, thus leading to malignant proliferation and chemotherapy resistance of tumor cells. Moreover, the expression of factors such as XIAP in the NF-κB anti-apoptotic pathway was downregulated after the knockdown of TLR4, and the malignant promotion effect of pyroptotic macrophages on PTCL cells was also reversed. Our findings revealed the mechanism of pyroptotic macrophages promoting the malignant biological behavior of PTCL and elucidated the key role of TLR4 in this process. In-depth analysis of this mechanism will contribute to understanding the regulatory effect of PTCL by the tumor microenvironment and providing new ideas for the clinical treatment of PTCL.

11.
Top Curr Chem (Cham) ; 382(2): 11, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589726

RESUMEN

Silicone surfactants have garnered significant research attention owing to their superior properties, such as wettability, ductility, and permeability. Small-molecular silicone surfactants with simple molecular structures outperform polymeric silicone surfactants in terms of surface activity, emulsification, wetting, foaming, and other areas. Moreover, silicone surfactants with small molecules exhibit a diverse and rich molecular structure. This review discusses various synthetic routes for the synthesis of different classes of surfactants, including single-chain, "umbrella" structure, double chain, bolaform, Gemini, and stimulus-responsive surfactants. The fundamental surface/interface properties of the synthesized surfactants are also highlighted. Additionally, these surfactants have demonstrated enormous potential in agricultural synergism, drug delivery, mineral flotation, enhanced oil recovery, separation, and extraction, and foam fire-fighting.


Asunto(s)
Siliconas , Tensoactivos , Tensoactivos/química , Propiedades de Superficie , Estructura Molecular
12.
J Hazard Mater ; 471: 134310, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640677

RESUMEN

Microbial interactions, particularly metabolic cross-feeding, play important roles in removing recalcitrant environmental pollutants; however, the underlying mechanisms involved in this process remain unclear. Thus, this study aimed to elucidate the mechanism by which metabolic cross-feeding occurs during synergistic dibenzofuran degradation between a highly efficient degrader, Rhodococcus sp. strain p52, and a partner incapable of utilizing dibenzofuran. A bottom-up approach combined with pairwise coculturing was used to examine metabolic cross-feeding between strain p52 and Arthrobacter sp. W06 or Achromobacter sp. D10. Pairwise coculture not only promoted bacterial pair growth but also facilitated dibenzofuran degradation. Specifically, strain p52, acting as a donor, released dibenzofuran metabolic intermediates, including salicylic acid and gentisic acid, for utilization and growth, respectively, by the partner strains W06 and D10. Both salicylic acid and gentisic acid exhibited biotoxicity, and their accumulation inhibited dibenzofuran degradation. The transcriptional activity of the genes responsible for the catabolism of dibenzofuran and its metabolic intermediates was coordinately regulated in strain p52 and its cocultivated partners, thus achieving synergistic dibenzofuran degradation. This study provides insights into microbial metabolic cross-feeding during recalcitrant environmental pollutant removal.


Asunto(s)
Biodegradación Ambiental , Rhodococcus , Ácido Salicílico , Rhodococcus/metabolismo , Ácido Salicílico/metabolismo , Dibenzofuranos/metabolismo , Benzofuranos/metabolismo , Gentisatos/metabolismo , Interacciones Microbianas
13.
Medicine (Baltimore) ; 103(14): e37701, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38579043

RESUMEN

RATIONALE: Hysterectomy after microwave ablation (MWA) is more difficult than conventional surgery which increases the probability of postoperative complications due to MWA's collateral thermal damage to nearby intestines. Here we report a case of multiple postoperative complications after hysterectomy following MWA. PATIENT CONCERNS: A 44-year-old female was admitted due to progressive abdominal pain during menstruation for 30 years and no relief 1 year after MWA. Hysterectomy was performed. Intraoperative findings: pelvic inflammatory exudation; the uterus and the left adnexa were extensively and densely adhered to the intestine, bladder, pelvic wall and surrounding tissues; the local tissue of the uterus was brittle and dark yellow. Intestinal obstruction, abdominal infection and urinary fistula occurred after hysterectomy. DIAGNOSES: 1. Adenomyosis. 2. Endometrial polyps. 3. Left chocolate cyst of ovary. 4. Pelvic adhesions. 5. Pelvic inflammation. INTERVENTIONS: The patient underwent intestinal obstruction catheter implantation, ultrasound-guided pelvic fluid mass puncture drainage, right kidney puncture and fistula drainage, right ureteral bladder replantation, and right ureteral stent implantation. OUTCOMES: After 48 days of comprehensive treatment, the patient was cured and discharged. LESSONS: Microwave ablation has a poor therapeutic effect on diffuse adenomyosis, and should avoid excessive ablation during the ablation process.


Asunto(s)
Adenomiosis , Obstrucción Intestinal , Laparoscopía , Femenino , Humanos , Adulto , Adenomiosis/cirugía , Microondas/uso terapéutico , Histerectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
14.
Diabetes Metab Syndr Obes ; 17: 1611-1619, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38616993

RESUMEN

Background: Von Hippel-Lindau (VHL) syndrome is characterized by tumorous lesions affecting multiple organs. Pancreatic involvement in VHL syndrome can present as endocrine tumors and pancreatic cysts, which can interfere with both exocrine and endocrine functions of the pancreas. Diabetes is an uncommon complication of VHL syndrome. Purpose: This study aims to summarize the various mechanisms of diabetes in VHL syndrome by reporting two cases and conducting a literature review. Methods: We analyzed the clinical and imaging data of two patients with VHL syndrome and diabetes. Additionally, we reviewed the existing literature to explore the clinical diversities and management strategies for VHL syndrome complicated with diabetes. Results: The first patient presented with liver metastasis of pancreatic neuroendocrine tumor and multiple pheochromocytoma. After surgery, the patient's diabetic control improved, as evidenced by a significant reduction in insulin dosage. This indicates a potential insulin resistance due to elevated metanephrine levels prior to surgery and partial insulin deficiency caused by distal pancreatectomy. The second patient had multiple hemangioblastomas, as well as multiple pancreatic cysts and positive pancreatic islet autoantibodies. Diabetes in this case may be attributed to pancreatic lesions and the coexistence of autoimmune insulitis. A literature review of other patients with VHL combined with diabetes revealed multiple mechanisms, including increased catecholamine levels, pancreatic lesions, surgical removal of pancreatic tissue, endocrine treatment, and possibly the coexistence of autoimmune insulitis. Conclusion: VHL syndrome complicated with diabetes involves diverse mechanisms.

15.
J Chem Phys ; 160(16)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38661200

RESUMEN

In extreme and nanoconfinement conditions, the tetrahedral arrangement of water molecules is challenged, resulting in a rich and new phase behavior unseen in bulk phases. The unique phase behavior of water confined in hydrophobic nanoslits has been previously observed, such as the formation of a variety of two-dimensional (2D) ices below the freezing temperature. The primary identified 2D ice phase, termed square tube ice (STI), represents a unique arrangement of water molecules in 2D ice, which can be viewed as an array of 1D ice nanotubes stacked in the direction parallel to the confinement plane. In this study, we report the molecular dynamics (MD) simulations evidence of a novel 2D ice phase, namely, helical square tube ice (H-STI). H-STI is characterized by the stacking of helical ice nanotubes in the direction parallel to the confinement plane. Its structural specificity is evident in the presence of helical square ice nanotubes, a configuration unseen in both STI and single-walled ice nanotubes. A detailed analysis of the hydrogen bonding strength showed that H-STI is a 2D ice phase diverging from the Bernal-Fowler-Pauling ice rules by forming only two strong hydrogen bonds between adjacent molecules along its helical ice chain. This arrangement of strong hydrogen bonds along ice nanotube and weak bonds between the ice nanotube shows a similarity to quasi-one-dimensional van der Waals materials. Ab initio molecular dynamics simulations (over a 30 ps) were employed to further verify H-STI's stability at 1 GPa and temperature up to 200 K.

16.
Proc Natl Acad Sci U S A ; 121(15): e2315730121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38557188

RESUMEN

Microdroplets are a class of soft matter that has been extensively employed for chemical, biochemical, and industrial applications. However, fabricating microdroplets with largely controllable contact-area shape and apparent contact angle, a key prerequisite for their applications, is still a challenge. Here, by engineering a type of surface with homocentric closed-loop microwalls/microchannels, we can achieve facile size, shape, and contact-angle tunability of microdroplets on the textured surfaces by design. More importantly, this class of surface topologies (with universal genus value = 1) allows us to reveal that the conventional Gibbs equation (widely used for assessing the edge effect on the apparent contact angle of macrodroplets) seems no longer applicable for water microdroplets or nanodroplets (evidenced by independent molecular dynamics simulations). Notably, for the flat surface with the intrinsic contact angle ~0°, we find that the critical contact angle on the microtextured counterparts (at edge angle 90°) can be as large as >130°, rather than 90° according to the Gibbs equation. Experiments show that the breakdown of the Gibbs equation occurs for microdroplets of different types of liquids including alcohol and hydrocarbon oils. Overall, the microtextured surface design and topological wetting states not only offer opportunities for diverse applications of microdroplets such as controllable chemical reactions and low-cost circuit fabrications but also provide testbeds for advancing the fundamental surface science of wetting beyond the Gibbs equation.

17.
Opt Express ; 32(4): 6258-6265, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439333

RESUMEN

Quasi-two-dimensional perovskites have attracted widespread interest in developing low-cost high-quality small lasers. The nano cavity based on topologically protected valley edge states can be robust against special defects. Here, we report a high-quality two-dimensional perovskite topological photonic crystal laser based on the quantum valley Hall effect. By adjusting the position of the air holes relative to the pillar, radiation leakage in topological edge states is reduced to a large extent, electric field distribution becomes more uniform and the quality factor can be as high as 3.6 × 104. Our findings could provide opportunities for the development of high-power, stable perovskite lasers with topological protection.

18.
Phys Chem Chem Phys ; 26(14): 11094-11104, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38530648

RESUMEN

Aqueous ion batteries have great commercial potential in green power and energy storage due to their green nature, safety and high ionic conductivities. Different from organic electrolytes, alkali ions (Li+, Na+, and K+) inevitably bring water molecules into the electrodes during the charging/discharging process due to the hydration of ions with water molecules. The selectivity of alkali ions and the mechanism of how water molecules are involved in the ion extraction/insertion process in the electrodes have not been clarified. In this study, we focus on the characteristics of the intra-layer distribution of different hydrated ions (Li+, Na+, and K+) and the quantitative analysis of the selectivity of hydrated cations in aqueous batteries. We found that the concentration of hydrated ions greatly affects their distribution within the 1T-MoS2 layers, and the presence of hydrogen bonding and O-O repulsive forces between water molecules causes the hydrated ions to gradually form chains from the dispersed state under the effect of hydrogen bonding and ionic bonding, then further form strips, and ultimately be densely dispersed within the whole layer. In addition, the chemical potential difference of hydrated ions is the key to the competitive reaction, and we quantitatively analyze the selectivity relationship between hydrated cations throughout the charging and discharging process; hydrated sodium ions will have better performance than lithium and potassium ions in aqueous batteries.

19.
PLoS One ; 19(3): e0300800, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38512976

RESUMEN

Mining wastewater with heavy metals poses a serious threat to the ecological environment. However, the acute single and combined ecological effects of heavy metals, such as chromium (Cr) and nickel (Ni), on freshwater ostracods, and the development of relevant prediction models, remain poorly understood. In this study, Heterocypris sp. was chosen to investigate the single and combined acute toxicity of Cr and Ni. Then, the quantitative structure-activity relationship (QSAR) model was used to predict the combined toxicity of Cr and Ni. The single acute toxicity experiments revealed high toxicity for both Cr and Ni. In addition, Cr exhibited greater toxicity compared to Ni, as evidenced by its lower 96-hour half-lethal concentration (LC50) of 1.07 mg/L compared to 4.7 mg/L for Ni. Furthermore, the combined acute toxicity experiments showed that the toxicity of Cr-Ni was higher than Ni but lower than Cr. Compared with the concentration addition (CA) and independent action (IA) models, the predicted results of the QSAR model were more consistent with the experimental results for the Cr-Ni combined acute toxicity. So, the high accuracy of QSAR model identified its feasibility to predict the toxicity of heavy metal pollutants in mining wastewater.


Asunto(s)
Metales Pesados , Níquel , Animales , Níquel/toxicidad , Níquel/análisis , Cromo/toxicidad , Cromo/análisis , Relación Estructura-Actividad Cuantitativa , Aguas Residuales/toxicidad , Metales Pesados/toxicidad , Metales Pesados/análisis , Crustáceos , Monitoreo del Ambiente
20.
J Phys Chem Lett ; 15(7): 2096-2104, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38358755

RESUMEN

Excitonic effects caused by the Coulomb interaction between electrons and holes play a crucial role in photocatalysis at the molecule/metal oxide interface. As an ideal model for investigating the excitonic effect, coadsorption and photodissociation of water and methanol molecules on titanium dioxide involve complex ground-state thermalcatalytic and excited-state photocatalytic reaction processes. Herein, we systemically investigate the excited-state electronic structures of the coadsorption of H2O and CH3OH molecules on a rutile TiO2(110) surface by linear-response time-dependent density functional theory calculations and probe the reaction path for generating HCOOH or CO2, from ground-state and excited-state perspectives. The reaction barriers in excited-state calculations are significantly different from those in ground-state calculations during three processes, with the largest decrease being 0.94 eV for the Ti5c-O-CH2-O-Ti5c formation process.

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