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1.
Huan Jing Ke Xue ; 45(8): 4915-4922, 2024 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-39168707

RESUMO

Microorganisms produce extracellular enzymes to meet elemental requirements and cope with stoichiometric imbalances of resources. To gain insights into the cycling of C, N, and P, the activities of the C∶N∶P acquisition enzymes have been extensively investigated. To detect the effects of long-term fertilization practices on soil nutrient balance and characteristics of soil enzymatic stoichiometry in black soil, four different fertilization treatments were selected: no fertilization (CK), nitrogen fertilizer (N), phosphorus fertilizer (P), and combination of nitrogen and phosphorus fertilizers (NP). Soil samples were collected in both April 2021 and April 2022 to determine soil enzyme activities and their stoichiometric characteristics. The results showed that soil acid phosphatase and ß-D-glucosidase activities were significantly higher in the N and NP treatments than in CK by 68%-158% and 26%-222%, respectively. Soil ß-N-acetylaminoglucosidase activities were significantly higher in the P and NP treatments, with the highest around 75.48 nmol·ï¼ˆg·h)-1 and 106.81 nmol·ï¼ˆg·h)-1, respectively. Two-way ANOVA analysis showed that N and P inputs had a great impact on soil enzyme activities. Redundancy analysis showed that the main factors controlling enzyme activities were soil pH, microbial biomass phosphorus, and soil available P content. It was found that N inputs significantly increased enzyme vector length, which was ranged from 1.32 to 1.52, and the enzyme vector angles were all larger than 45°, suggesting C and P co-limited in the black soils. These findings suggest that 40 years of fertilization have had a great impact on soil enzymes and the related resource use strategy, which provides great implications for assessing soil nutrients balance and soil sustainability.


Assuntos
Fertilizantes , Nitrogênio , Fósforo , Microbiologia do Solo , Solo , Solo/química , Fósforo/análise , Fosfatase Ácida/metabolismo , Carbono/análise , Fatores de Tempo , China
2.
Artigo em Inglês | MEDLINE | ID: mdl-39160115

RESUMO

BACKGROUND: Cytolethal distending toxin (CDT) belongs to the genotoxin family and is closely related to Campylobacter jejuni-associated gastroenteritis. We recently reported that CDT triggers the danger-associated molecular pattern (DAMP) signaling to exert deleterious effects on host cells. However, how CDT traffics in cells and the mechanism of CDT intoxication remain to be elucidated. METHODS: Recombinant CDT subunits (CdtA, CdtB, and CdtC) were purified, and their activity was characterized in gastrointestinal cells. Molecular approaches and image tracking were employed to analyze the delivery of CDT in host cells. RESULTS: In this study, we found that CDT interacts with the receptor of advanced glycation end products (RAGE) and high mobility group box 1 (HMGB1) to enter the cells. Our results further showed that CdtB transport in cells through the dynamin-dependent endocytic pathway and lysosome is involved in this process. Conversely, blockage of RAGE signaling resulted in a reduction in CDT-arrested cell cycles, indicating that RAGE is involved in CDT intracellular transport and its subsequent pathogenesis. CONCLUSION: Our results demonstrate that RAGE is important for CDT trafficking in the cells. These findings expand our understanding of important issues related to host cell intoxication by C. jejuni CDT.

4.
Nanoscale ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39114954

RESUMO

Transparent memristor-based neuromorphic synapses are expected to be specialised devices for high-speed information transmission and processing. The synaptic linearity and potentiation/depression cycles are imperative issues for the application of memristors. This work explores a memristor for improving switching uniformity by introducing a thin HfOx interfacial layer as a diffusion-limiting layer sandwiched between WOx and ITO bottom electrodes. An optimized HfOx thickness not only provides the best switching properties but also shows superior synaptic properties. The optimized 15 nm thin WOx layer can retain the memristor's excellence in P/D linearity, a cycling stability of 494 epochs and image recognition up to 3 mm bending, making it suitable for flexible devices. The artificial synapse is capable of reversible short-term and long-term learning behaviors confirmed by spike-timing-dependent-plasticity (STDP) results. X-ray photoelectron spectroscopy confirms the device composition and provides the oxygen vacancy concentration at the WOx/HfOx interface to realize the switching mechanism. The thicknesses of the different layers are estimated from the high-resolution transmission electron microscopy observations. The fabricated device exhibits 92.2% transparency, as confirmed by the UV-Vis spectrum.

5.
Zhonghua Nan Ke Xue ; 30(2): 151-156, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-39177349

RESUMO

OBJECTIVE: To evaluate the efficiency of the four domestic language models, ERNIE Bot, ChatGLM2, Spark Desk and Qwen-14B-Chat, all with a massive user base and significant social attention, in response to consultations about PCa-related perioperative nursing and health education. METHODS: We designed a questionnaire that includes 15 questions commonly concerned by patients undergoing radical prostatectomy and 2 common nursing cases, and inputted the questions into each of the four language models for simulation consultation. Three nursing experts assessed the model responses based on a pre-designed Likert 5-point scale in terms of accuracy, comprehensiveness, understandability, humanistic care, and case analysis. We evaluated and compared the performance of the four models using visualization tools and statistical analyses. RESULTS: All the models generated high-quality texts with no misleading information and exhibited satisfactory performance. Qwen-14B-Chat scored the highest in all aspects and showed relatively stable outputs in multiple tests compared with ChatGLM2. Spark Desk performed well in terms of understandability but lacked comprehensiveness and humanistic care. Both Qwen-14B-Chat and ChatGLM2 demonstrated excellent performance in case analysis. The overall performance of ERNIE Bot was slightly inferior. All things considered, Qwen-14B-Chat was superior to the other three models in consultations about PCa-related perioperative nursing and health education. CONCLUSION: In PCa-related perioperative nursing, large language models represented by Qwen-14B-Chat are expected to become powerful auxiliary tools to provide patients with more medical expertise and information support, so as to improve the patient compliance and the quality of clinical treatment and nursing.


Assuntos
Enfermagem Perioperatória , Humanos , Inquéritos e Questionários , Masculino , China , Educação em Saúde/métodos , Idioma , Prostatectomia/métodos
6.
Int J Biol Macromol ; 278(Pt 2): 134783, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153673

RESUMO

Glucagon-like peptide-1 (GLP-1) as a multifunctional hormone is secreted mainly from enteroendocrine L-cells, and enhancing its endogenous secretion has potential benefits of regulating glucose homeostasis and controlling body weight gain. In the present study, a novel polysaccharide (h-DHP) with high ability to enhance plasma GLP-1 level in mice was isolated from Dendrobium huoshanense protocorm-like bodies under the guidance of activity evaluation. Structural identification showed that h-DHP was an acidic polysaccharide with the molecular weight of 1.38 × 105 Da, and was composed of galactose, glucose, arabinose and glucuronic acid at a molar ratio of 15.7: 11.2: 4.5: 1.0 with a backbone consisting of →5)-α-L-Araf-(1→, →3)-α-D-Galp-(1→, →6)-α-D-Galp-(1→, →3,6)-α-D-Galp-(1→, →6)-ß-D-Glcp-(1→ and →4,6)-ß-D-Glcp-(1→ along with branches consisting of α-L-Araf-(1→, α-D-Galp-(1→, α-D-GlcAp-(1→, ß-D-Glcp-(1→ and →4)-ß-D-Glcp-(1→. Animal experiments with different administration routes demonstrated that h-DHP-enhanced plasma GLP-1 level was attributed to h-DHP-promoted GLP-1 secretion in the enteroendocrine L-cells, which was supported by h-DHP-enhanced extracellular GLP-1 level in STC-1 cells. Inhibition of adenylate cyclase and phospholipase C indicated that cAMP and cAMP-triggered intracellular Ca2+ increase participated in h-DHP-promoted GLP-1 secretion. These results suggested that h-DHP has the potential of enhancing endogenous GLP-1 level through h-DHP-promoted and cAMP-mediated GLP-1 secretion from enteroendocrine cells.

7.
Chem Sci ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39176247

RESUMO

An important subject of porous organic materials is their capacity to access enantioselectivity due to their high surface area, controllable pore size, and ease of functionalization. However, recyclability of enantio-separation is a challenge, mainly due to the complex procedures of recovery and refreshing from enantiomers. For the first time, we combined nanochannel technology and supramolecular chiral assembly to achieve efficient enantioselectivity. Fine-designed amphiphilic chiral rod-coil molecules 1-3 were immobilized to SBA-15 pore walls to form SA-M1-3 (abbreviation for amino-functionalized SBA-15 connected to molecules 1-3), which commenced chiral aggregation inside the channels. The experimental results indicated that the strong π-π stacking interaction between the rigid terphenyl groups, as well as hydrophilic-hydrophobic interaction of the amphiphiles, assisted in chiral arrangement in aqueous solution, and was accompanied by amplification of chirality. As a result, porous chiral channels exhibiting enhanced efficiency in asymmetric synthesis were manufactured, where enantioselectivity can be controlled by the initial structural design of amphiphiles that induce chiral aggregation behaviors. The chiral centers of SA-M1 and SA-M2 are located on hydrophobic and hydrophilic coils, respectively, while SA-M3 possesses both chiral coils. The SA-M materials proceeded with chiral aggregation and behaved efficiently for enantioselectivity. SA-M3, which contained the most chiral centers, showed the most optimal enantioselectivity with an enantiomeric excess (ee) value up to 71.75%, which occurred because of the strongly driven chiral aggregation of the hydrophobic and hydrophilic chiral coils. The covalent hybrid structures of the SA-M materials can be easily refreshed simply through washing, and exhibited excellent recyclability with negligible loss of efficiency. Therefore, the SA-M materials have the ability to provide sustainable and reliable application value for enantiomer separation.

8.
bioRxiv ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-39071317

RESUMO

A major contributor to poor sensitivity to anti-cancer kinase inhibitor therapy is drug-induced cellular adaptation, whereby remodeling of signaling and gene regulatory networks permits a drug-tolerant phenotype. Here, we resolve the scale and kinetics of critical subcellular events following oncogenic kinase inhibition and preceding cell cycle re-entry, using mass spectrometry-based phosphoproteomics and RNA sequencing to capture molecular snapshots within the first minutes, hours, and days of BRAF kinase inhibitor exposure in a human BRAF -mutant melanoma model of adaptive therapy resistance. By enriching specific phospho-motifs associated with mitogenic kinase activity, we monitored the dynamics of thousands of growth- and survival-related protein phosphorylation events under oncogenic BRAF inhibition and drug removal. We observed early and sustained inhibition of the BRAF-ERK axis, gradual downregulation of canonical cell cycle-dependent signals, and three distinct and reversible phase transitions toward quiescence. Statistical inference of kinetically-defined signaling and transcriptional modules revealed a concerted response to oncogenic BRAF inhibition and a dominant compensatory induction of SRC family kinase (SFK) signaling, which we found to be at least partially driven by accumulation of reactive oxygen species via impaired redox homeostasis. This induction sensitized cells to co-treatment with an SFK inhibitor across a panel of patient-derived melanoma cell lines and in an orthotopic mouse xenograft model, underscoring the translational potential for measuring the early temporal dynamics of signaling and transcriptional networks under therapeutic challenge.

9.
IUCrdata ; 9(Pt 6): x240489, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974854

RESUMO

In the crystal structure of the title compound, {[Co(C11H9NSO5)(C10H9N3)]0.5C3H7NO·H2O} n or {[Co(dmtb)(dpa)]·0.5DMF·H2O} n (dmtb2- = 5-[(di-meth-yl-amino)-thioxometh-oxy]-1,3-benzene-dicarboxyl-ate and dpa = 4,4'-di-pyridyl-amine), an assembly of periodic [Co(C11H9NSO5)(C10H9N3)] n layers extending parallel to the bc plane is present. Each layer is constituted by distorted [CoO4N2] octa-hedra, which are connected through the µ 2-coordination modes of both dmtb2- and dpa ligands. Occupationally disordered water and di-meth-yl-formamide (DMF) solvent mol-ecules are located in the voids of the network to which they are connected through hydrogen-bonding inter-actions.

10.
bioRxiv ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39026720

RESUMO

While paradigms for patterning of cell fates in development are well-established, paradigms for patterning morphogenesis, particularly when organ shape is influenced by the extracellular matrix (ECM), are less so. Morphogenesis of the Drosophila egg chamber (follicle) depends on anterior-posterior distribution of basement membrane (BM) components such as Collagen IV (Col4), whose symmetric gradient creates tissue mechanical properties that specify the degree of elongation. Here we show that the gradient is not regulated by Col4 transcription but instead relies on post-transcriptional mechanisms. The metalloprotease ADAMTS-A, expressed in a gradient inverse to that of Col4, limits Col4 deposition in the follicle center and manipulation of its levels can cause either organ hyper- or hypo-elongation. We present evidence that ADAMTS-A acts within the secretory pathway, rather than extracellularly, to limit Col4 incorporation into the BM. High levels of ADAMTS-A in follicle termini are normally dispensable but suppress Col4 incorporation when transcription is elevated. Our data show how an organ can employ patterned expression of ECM proteases with intracellular as well as extracellular activity to specify BM properties that control shape.

11.
Healthcare (Basel) ; 12(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39057517

RESUMO

Colonoscopy is an essential method for diagnosing and treating colorectal cancer, relying on effective bowel preparation to thoroughly examine the large intestinal mucosa. Traditional education involves printed instructions and verbal explanations but does not guarantee clear patient understanding. Poor bowel preparation can obscure mucosal visibility, delaying cancer diagnosis and treatment. A mobile medical model using Android devices for bowel preparation education was tested in a single-blind, randomized trial. This trial enrolled outpatients undergoing colonoscopy at the Endoscopy Center for Diagnostic and Treatment between 27 October 2021 and 31 December 2022. This study introduced the ColonClean app alongside traditional methods. After examination, endoscopists rated the preparation quality using the Aronchick scale. A data analysis was conducted using SPSS 25.0 to determine if there was a significant improvement in bowel preparation quality between the control group (traditional method) and the experimental group (traditional method plus the ColonClean app). Forty patients were recruited in each group. In the experimental group, all ratings were "fair", with 75% receiving an "excellent" or "good" rating, showing statistical significance (p = 0.016). The ColonClean app improves bowel preparation quality more effectively than traditional care instructions.

12.
Inorg Chem ; 63(30): 13938-13947, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38996364

RESUMO

The recent report of planar tetracoordinate hydrogen (ptH) in In4H+ is very intriguing in planar hypercoordinate chemistry. Our high-level CCSD(T) calculations revealed that the proposed D4h-symmetric ptH In4H+ is a first-order saddle point with an imaginary frequency in the out-of-plane mode of the hydrogen atom. In fact, at the CCSD(T)/aug-cc-pV5Z/aug-cc-pV5Z-PP level, the C4v isomer, with the H atom located 0.70 Å above the In4 plane, is 0.5 kcal/mol more stable than the D4h isomer. However, given the small perturbation from planarity and essentially barrierless C4v ↔ D4h ↔ C4v transition, the vibrationally averaged structure can still be considered as a planar. Extending our exploration to the InnTl4-nH+ (n = 0-3) systems, we found all these ptH structures, except for In2Tl2H+, to be the putative global minimum. The single σ-delocalized interaction between the central hydrogen atom and InnTl4-n ligand rings proves pivotal in establishing planarity and aromaticity and conferring substantial stability upon these rule-breaking ptH species.

13.
BMC Musculoskelet Disord ; 25(1): 551, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014378

RESUMO

BACKGROUND: The high prevalence of diabetic kidney disease (DKD) in the United States necessitates further investigation into its impact on complications associated with total hip arthroplasty (THA). This study utilizes a large nationwide database to explore risk factors in DKD cases undergoing THA. METHODS: This research utilized a case-control design, leveraging data from the national inpatient sample for the years 2016 to 2019. Employing propensity score matching (PSM), patients diagnosed with DKD were paired on a 1:1 basis with individuals free of DKD, ensuring equivalent age, sex, race, Elixhauser Comorbidity Index (ECI), and insurance coverage. Subsequently, comparisons were drawn between these PSM-matched cohorts, examining their characteristics and the incidence of post-THA complications. Multivariate logistic regression analysis was then employed to evaluate the risk of early complications after surgery. RESULTS: DKD's prevalence in the THA cohort was 2.38%. A 7-year age gap separated DKD and non-DKD patients (74 vs. 67 years, P < 0.0001). Additionally, individuals aged above 75 exhibited a substantial 22.58% increase in DKD risk (49.16% vs. 26.58%, P < 0.0001). Notably, linear regression analysis yielded a significant association between DKD and postoperative acute kidney injury (AKI), with DKD patients demonstrating 2.274-fold greater odds of AKI in contrast with non-DKD individuals (95% CI: 2.091-2.473). CONCLUSIONS: This study demonstrates that DKD is a significant risk factor for AKI in patients undergoing total hip arthroplasty. Optimizing preoperative kidney function through appropriate interventions might decrease the risk of poor prognosis in this population. More prospective research is warranted to investigate the potential of targeted kidney function improvement strategies in reducing AKI rates after THA. The findings of this study hold promise for enhancing preoperative counseling by surgeons, enabling them to provide DKD patients undergoing THA with more precise information regarding the risks associated with their condition.


Assuntos
Artroplastia de Quadril , Bases de Dados Factuais , Nefropatias Diabéticas , Complicações Pós-Operatórias , Humanos , Artroplastia de Quadril/efeitos adversos , Masculino , Feminino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Idoso , Pessoa de Meia-Idade , Nefropatias Diabéticas/epidemiologia , Estudos de Casos e Controles , Estados Unidos/epidemiologia , Fatores de Risco , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Procedimentos Cirúrgicos Eletivos/tendências , Prevalência , Idoso de 80 Anos ou mais , Incidência
14.
Int J Mol Sci ; 25(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39000427

RESUMO

The amyloid-beta peptide (Aß) is the neurotoxic component in senile plaques of Alzheimer's disease (AD) brains. Previously we have reported that Aß toxicity is mediated by the induction of sonic hedgehog (SHH) to trigger cell cycle re-entry (CCR) and apoptosis in post-mitotic neurons. Basella alba is a vegetable whose polysaccharides carry immunomodulatory and anti-cancer actions, but their protective effects against neurodegeneration have never been reported. Herein, we tested whether polysaccharides derived from Basella alba (PPV-6) may inhibit Aß toxicity and explored its underlying mechanisms. In differentiated rat cortical neurons, Aß25-35 reduced cell viability, damaged neuronal structure, and compromised mitochondrial bioenergetic functions, all of which were recovered by PPV-6. Immunocytochemistry and western blotting revealed that Aß25-35-mediated induction of cell cycle markers including cyclin D1, proliferating cell nuclear antigen (PCNA), and histone H3 phosphorylated at Ser-10 (p-Histone H3) in differentiated neurons was all suppressed by PPV-6, along with mitigation of caspase-3 cleavage. Further studies revealed that PPV-6 inhibited Aß25-35 induction of SHH; indeed, PPV-6 was capable of suppressing neuronal CCR and apoptosis triggered by the exogenous N-terminal fragment of sonic hedgehog (SHH-N). Our findings demonstrated that, in the fully differentiated neurons, PPV-6 exerts protective actions against Aß neurotoxicity via the downregulation of SHH to suppress neuronal CCR and apoptosis.


Assuntos
Peptídeos beta-Amiloides , Apoptose , Ciclo Celular , Proteínas Hedgehog , Neurônios , Polissacarídeos , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/toxicidade , Proteínas Hedgehog/metabolismo , Animais , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Apoptose/efeitos dos fármacos , Ratos , Polissacarídeos/farmacologia , Polissacarídeos/química , Ciclo Celular/efeitos dos fármacos , Fragmentos de Peptídeos , Sobrevivência Celular/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 334-340, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-38953257

RESUMO

Objective To explore the relationship between the expression levels of microRNA-155 (miR-155) and suppressor of cytokine signaling 1 (SOCS1) in the colonic mucosal tissue of patients with ulcerative colitis (UC) and the severity of the disease.Methods A total of 130 UC patients admitted to the Second Affiliated Hospital of Hebei North University from September 2021 to June 2023 were selected.According to the modified Mayo score system,the patients were assigned into an active stage group (n=85) and a remission stage group (n=45).According to the modified Truelove and Witts classification criteria,the UC patients at the active stage were assigned into a mild group (n=35),a moderate group (n=30),and a severe group (n=20).A total of 90 healthy individuals who underwent colonoscopy for physical examination or those who had normal colonoscopy results after single polypectomy and excluded other diseases were selected as the control group.The colonic mucosal tissues of UC patients with obvious lesions and the colonic mucosal tissue 20 cm away from the anus of the control group were collected.The levels of miR-155 and SOCS1 mRNA in tissues were determined by fluorescence quantitative PCR,and the expression of SOCS1 protein in tissues was determined by immunohistochemistry.The correlations of the levels of miR-155 and SOCS1 mRNA in the colonic mucosal tissue with the modified Mayo score of UC patients were analyzed.The values of the levels of miR-155 and SOCS1 mRNA in predicting the occurrence of severe illness in the UC patients at the active stage were evaluated.Results Compared with the control group and the remission stage group,the active stage group showed up-regulated expression level of miR-155,down-regulated level of SOCS1 mRNA,and decreased positive rate of SOCS1 protein in the colonic mucosal tissue (all P<0.001).The expression level of miR-155 and modified Mayo score in colonic mucosal tissues of UC patients at the active stage increased,while the mRNA level of SOCS1 was down-regulated as the disease evolved from being mild to severe (all P<0.001).The modified Mayo score was positively correlated with the miR-155 level and negative correlated with the mRNA level of SOCS1 in colonic mucosal tissues of UC patients (all P<0.001).The high miR-155 level (OR=2.762,95%CI=1.284-5.944,P=0.009),low mRNA level of SOCS1 (OR=2.617,95%CI=1.302-5.258,P=0.007),and modified Mayo score≥12 points (OR=3.232,95%CI=1.450-7.204,P=0.004) were all risk factors for severe disease in the UC patients at the active stage.The area under curve of miR-155 combined with SOCS1 mRNA in predicting severe illness in the UC patients at the active stage was 0.920.Conclusions The expression levels of miR-155 and SOCS1 mRNA were correlated with the disease severity in the UC patients at the active stage.The combination of the two indicators demonstrates good performance in predicting the occurrence of severe illness in UC patients at the active stage.


Assuntos
Colite Ulcerativa , Mucosa Intestinal , MicroRNAs , Proteína 1 Supressora da Sinalização de Citocina , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colite Ulcerativa/fisiopatologia , Colo/metabolismo , Colo/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Índice de Gravidade de Doença , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo
16.
Eur J Pharm Biopharm ; 202: 114413, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029878

RESUMO

In-situ API crystallization in carrier matrices has attracted extensive attention in recent years for its advantages over traditional preparation processes. However, due to the lack of systemic research on molecular self-assembly behaviors, the products obtained by in-situ crystallization suffer from the problems of polymorphic transformation and drug expulsion during storage, limiting its industrial application. This paper investigates the in-situ sequential crystallization behavior of tristearin (SSS) and fenofibrate (FEN), utilizing SSS as the carrier and FEN as the API. It was found that the behavior of mixed crystallization significantly differs from single-component crystallization, including direct formation of stable form of SSS and the rapid crystallization of FEN. During the crystallization process, the melting FEN promotes the movement of SSS molecules, while the sliding of SSS lamellae, in turn, provides a mechanical stimulus to enhance the nucleation of FEN. Based on the observed synergistic crystallization behavior, the distribution and stability of the API within FEN solid lipid microparticles (SLMs) during storage were evaluated, while also examining the stability variations in SLMs formulated at different cooling rates and drug loading concentrations. The findings indicate that the initial nucleated FEN results in a decrease in the surrounding molten FEN and the irregularity of the SSS lamellas, thereby preventing the remaining molten FEN from achieving complete crystallization within a brief period. Due to the compatibility between FEN and SSS, some SSS may blend with the molten FEN, potentially resulting in further crystallization during storage and consequently increasing the risk of drug expulsion.


Assuntos
Cristalização , Estabilidade de Medicamentos , Fenofibrato , Fenofibrato/química , Lipídeos/química , Triglicerídeos/química , Tamanho da Partícula , Portadores de Fármacos/química , Hipolipemiantes/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Armazenamento de Medicamentos
17.
Langmuir ; 40(27): 14166-14172, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38916980

RESUMO

In recent years, liquid crystal materials have drawn great interest because of their wide range of applications. Among various thermochromic materials, cholesteric liquid crystalline (CLC) materials have been well studied and reported. CLC materials have the advantages of ready manipulation and multiple color transitions. For the further development of smart clothing and wearable electronics, however, the incorporation of CLC materials into polymers still remains challenging. The difficulties lie in the prevention of leakage of CLC and retention of the cholesteric liquid crystalline phase. In this work, we demonstrate a versatile nonsolvent and phase separation method using polar solvents to incorporate CLC microspheres into polymer matrix. Poly(vinyl alcohol) (PVA), a water-soluble polymer, is chosen as the polymer because of its high transparency and ease to handle. Using spin-coating and wet spinning techniques, PVA/CLC films and fibers can be fabricated. The formation of CLC microspheres in the polymer matrix is characterized through optical and polarized microscopy. Compared with the CLC films, the PVA/CLC composites demonstrate superior thermal stability. Moreover, both PVA/CLC films and fibers exhibit good color stability from the electrical tests. This work provides an effective strategy to prepare polymer/CLC composites, paving a wide avenue toward applications in smart textiles, display technologies, and medical devices.

18.
Imeta ; 3(2): e182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38882487

RESUMO

The Microbiome Protocols eBook (MPB) serves as a crucial bridge, filling gaps in microbiome protocols for both wet experiments and data analysis. The first edition, launched in 2020, featured 152 meticulously curated protocols, garnering widespread acclaim. We now extend a sincere invitation to researchers to participate in the upcoming 2nd version of MPB, contributing their valuable protocols to advance microbiome research.

19.
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.

20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(6): 666-671, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38918185

RESUMO

Objective: To assess the effectiveness of suture button fixation Latarjet procedure under total arthroscopy for anterior shoulder instability with severe bone defects. Methods: The clinical data of 15 patients with severe bone defects and anterior shoulder instability treated with suture button fixation Latarjet procedure under total arthroscopy between June 2020 and February 2023 was retrospectively analyzed, including 11 males and 4 females, with an average age of 31.1 years (range, 20-54 years). Three-dimensional CT showed that the average glenoid bone defect was 24.4% (range, 16.3%-35.2%). The average number of shoulder dislocation was 4.2 times (range, 3-8 times). The disease duration ranged from 6 to 21 months with an average of 10.6 months. The operation time and intraoperative blood loss were recorded. The pain relief was evaluated by visual analogue scale (VAS) score, and the functional recovery of shoulder joint was evaluated by Rowe score, Walch-Duplay score, and American Association for Shoulder and Elbow Surgery (ASES) score before and after operation. The range of motion (ROM) of the shoulder joint was assessed, including active flexion, lateral external rotation, abduction 90° external rotation, and internal rotation. Three-dimensional CT was performed at 6 months after operation and at last follow-up to observe the absorption of bone graft, the position of bone graft and glenoid, and the healing of bone graft. Results: The operation was successfully completed in all patients. The operation time was 85-195 minutes, with an average of 123.0 minutes. The intraoperative blood loss was 20-75 mL, with an average of 26.5 mL. All patients were followed up 13-32 months, with an average of 18.7 months. During the follow-up, there was no serious complication such as shoulder joint infection, joint stiffness, or vascular and nerve injury. One patient had partial absorption of the transplanted bone and bone nonunion at 3 months after operation, but the pain of the shoulder joint relieved at last follow-up, and no redislocation of the shoulder joint occurred; no obvious bone fracture or dislocation of the shoulder joint was found in the other patients. Bone union was achieved at 6 months during follow-up. At last follow-up, the VAS score, Rowe score, Walch-Duplay score, and ASES score significantly improved when compared with those before operation ( P<0.05), while the ROM of active flexion, lateral external rotation, abduction 90° external rotation, and internal rotation of the shoulder joint was not significantly different from those before operation ( P>0.05). Conclusion: Suture button fixation Latarjet procedure under total arthroscopy can improve shoulder joint function in patients with severe anterior shoulder instability caused by bone defects, and imaging also indicates satisfactory placement of transplanted bone blocks.


Assuntos
Artroscopia , Instabilidade Articular , Articulação do Ombro , Humanos , Masculino , Feminino , Artroscopia/métodos , Adulto , Instabilidade Articular/cirurgia , Instabilidade Articular/etiologia , Articulação do Ombro/cirurgia , Adulto Jovem , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Luxação do Ombro/cirurgia , Resultado do Tratamento , Tomografia Computadorizada por Raios X
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