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1.
Clin Case Rep ; 12(4): e8774, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634096

RESUMO

Key Clinical Message: Anorectal gastrointestinal stromal tumors are extremely rare, constituting less than 0.1% of rectal tumors. Surgical resection using a transanal wide excision followed by adjuvant therapy with tyrosine kinase inhibitors can be a successful treatment combination to remove the mass and prevent recurrence while preserving the integrity of the anal sphincter. Abstract: Gastrointestinal stromal tumors (GISTs) are a rare subset of neoplasms, accounting for about 1%-2% of primary gastrointestinal malignancies. The stomach is the most common site for GISTs, with anorectal GISTs being exceptionally rare, representing only 0.1% of all rectal tumors. The standard approach for managing localized GIST involves complete surgical excision to achieve negative microscopic margins (R0) while preserving the tumor capsule and maintaining anal sphincter function. Surgical resection with transanal wide excision followed by adjuvant therapy using tyrosine kinase inhibitors can successfully remove the mass, prevent recurrence, and preserve the anal sphincter's integrity. Adjuvant therapy with imatinib is the recommended treatment for all localized GISTs assessed to have an intermediate or high risk of relapse. Here, we report a case of a 63-year-old male with a rectal GIST who underwent transanal wide excision followed by adjuvant therapy with tyrosine kinase inhibitors.

2.
World J Clin Cases ; 12(10): 1778-1784, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38660078

RESUMO

BACKGROUND: Rectocutaneous fistulae are common. The infection originates within the anal glands and subsequently extends into adjacent regions, ultimately resulting in fistula development. Cellular angiofibroma (CAF), also known as an angiomyofibroblastoma-like tumor, is a rare benign soft tissue neoplasm predominantly observed in the scrotum, perineum, and inguinal area in males and in the vulva in females. We describe the first documented case CAF that developed within a rectocutaneous fistula and manifested as a perineal mass. CASE SUMMARY: In the outpatient setting, a 52-year-old male patient presented with a 2-year history of a growing perineal mass, accompanied by throbbing pain and minor scrotal abrasion. Physical examination revealed a soft, well-defined, non-tender mass at the left buttock that extended towards the perineum, without a visible opening. The initial assessment identified a soft tissue tumor, and the laboratory data were within normal ranges. Abdominal and pelvic computed tomography (CT) revealed swelling of the abscess cavity that was linked to a rectal cutaneous fistula, with a track-like lesion measuring 6 cm × 0.7 cm in the left perineal region and attached to the left rectum. Rectoscope examination found no significant inner orifices. A left medial gluteal incision revealed a thick-walled mass, which was excised along with the extending tract, and curettage was performed. Histopathological examination confirmed CAF diagnosis. The patient achieved total resolution during follow-up assessments and did not require additional hospitalization. CONCLUSION: CT imaging supports perineal lesion diagnosis and management. Perineal angiofibromas, even with a cutaneous fistula, can be excised transperineally.

3.
Int J Ophthalmol ; 17(4): 713-720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638257

RESUMO

AIM: To analyze the distribution of refractive status in school-age children with different corneal curvatures (CC) and the correlation between CC and refractive status. METHODS: A total of 2214 school-aged children of grade 4 in Hangzhou who were screened for school myopia were included. Uncorrected distance visual acuity (UCDVA), non-cycloplegic refraction, axial length (AL), horizontal and vertical corneal curvature (K1, K2) were measured and spherical equivalent (SE), corneal curvature radius (CCR) and axial length/corneal radius of curvature ratio (AL/CR) were calculated. UCDVA<5.0 and SE≤-0.50 D were classified as school-screening myopia. According to the different CCRs, the patients were divided into the lower corneal curvature (LCC) group (CCR≥7.92) and the higher corneal curvature (HCC) group (CCR<7.92). Each group was further divided into the normal AL subgroup and the long AL subgroup. The refractive parameters were compared to identify any differences between the two groups. RESULTS: Both SE and AL were greater in the LCC group (P=0.013, P<0.001). The prevalence of myopia was 38% in the LCC group and 44% in the HCC group (P<0.001). The proportion of children without screening myopia was higher in the LCC group (62%) than in the HCC group (56%). Among these children without screening myopia, the proportion of long AL in the LCC group (24%) was significantly higher than that in the HCC group (0.012%; P<0.001). The change of SE in the LCC group was less affected by the increase of AL than that in the HCC group. CONCLUSION: School-aged children in the LCC group have a lower incidence of screening myopia and longer AL. Low CC can mask SE reduction and AL growth to some extent, and the change of AL growth change more in children with low CC than high CC. Before the onset of myopia, its growth rate is even faster than that after the onset of myopia.

4.
World J Gastrointest Surg ; 16(3): 944-954, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577069

RESUMO

BACKGROUND: Appendiceal mucinous neoplasms (AMNs), although not classified as rare, are relatively uncommon tumors most often discovered incidentally during colorectal surgery. Accurate identification of AMNs is difficult due to non-specific symptoms, overlapping tumor markers with other conditions, and the potential for misdiagnosis. This underscores the urgent need for precision in diagnosis to prevent severe complications. CASE SUMMARY: This case report describes the unexpected discovery and treatment of a low-grade AMN (LAMN) in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma (AC). Preoperatively, non-specific gastrointestinal symptoms and elevated tumor markers masked the presence of AMN. The tumor, presumed to be an AMN peritoneal cyst intraoperatively, was confirmed as LAMN through histopathological examination. The neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile: Positive for Homeobox protein CDX-2, Cytokeratin 20, special AT-rich sequence-binding protein 2, and Mucin 2 but negative for cytokeratin 7 and Paired box gene 8. This profile aids in distinguishing appendiceal and ovarian mucinous tumors. Postoperative recovery was uncomplicated, and the patient initiated adjuvant chemotherapy for the colon AC. CONCLUSION: This case highlights the diagnostic complexity of AMNs, emphasizing the need for vigilant identification to avert potential complications, such as pseudomyxoma peritonei.

5.
Discov Oncol ; 15(1): 102, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573548

RESUMO

BACKGROUND: Abnormal expression of protein tyrosine kinase 6 (PTK6) has been proven to be involved in the development of gynecological tumors. However, its immune-related carcinogenic mechanism in other tumors remains unclear. OBJECTIVE: The aim of this study was to identify PTK6 as a novel prognostic biomarker in pan-cancer, especially in lung adenocarcinoma (LUAD), which is correlated with immune infiltration, and to clarify its clinicopathological and prognostic significance. METHODS: The prognostic value and immune relevance of PTK6 were investigated by using bio-informatics in this study. PTK6 expression was validated in vitro experiments (lung cancer cell lines PC9, NCI-H1975, and HCC827; human normal lung epithelial cells BEAS-2B). Western blot (WB) revealed the PTK6 protein expression in lung cancer cell lines. PTK6 expression was inhibited by Tilfrinib. Colony formation and the Cell Counting Kit-8 (CCK-8) assay were used to detect cell proliferation. The wound healing and trans-well were performed to analyze the cell migration capacity. Then flow cytometry was conducted to evaluate the cell apoptosis. Eventually, the relationship between PTK6 and immune checkpoints was examined. WB was used to estimate the PD-L1 expression at different Tilfrinib doses. RESULTS: PTK6 was an independent predictive factor for LUAD and was substantially expressed in LUAD. Pathological stage was significantly correlated with increased PTK6 expression. In accordance with survival analysis, poor survival rate in LUAD was associated with a high expression level of PTK6. Functional enrichment of the cell cycle and TGF-ß signaling pathway was demonstrated by KEGG and GSEA analysis. Moreover, PTK6 expression considerably associated with immune infiltration in LUAD, as determined by immune analysis. Thus, the result of vitro experiments indicated that cell proliferation and migration were inhibited by the elimination of PTK6. Additionally, PTK6 suppression induced cell apoptosis. Obviously, PD-L1 protein expression level up-regulated while PTK6 was suppressed. CONCLUSION: PTK6 has predictive value for LUAD prognosis, and could up regulated PD-L1.

6.
BMC Surg ; 24(1): 122, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658932

RESUMO

Various studies have focused on the application of fibrin sealants (FS) in thyroid surgery. Utilizing a meta-analysis, this systematic review analyzed the findings of recent randomized controlled trials on the safety and efficacy of FS in patients who underwent thyroidectomy. The Cochrane Library, Web of Science, Embase, PubMed, and Medline databases were searched for relevant studies, without any language restrictions. Seven randomized controlled trials were included in the originally identified 69 studies. Overall, 652 patients received FS during thyroid surgery; their outcomes were compared with those of conventionally treated patients. The primary outcomes were total volume of wound drainage, length of hospitalization, and operative time. Significant differences were observed in the total volume of wound drainage (mean deviation (MD): -29.75, 95% confidence interval (CI): -55.39 to -4.11, P = 0.02), length of hospitalization (MD: -0.84, 95% CI: -1.02 to -0.66, P < 0.00001), and surgery duration (MD: -7.60, 95% CI: -14.75 to -0.45, P = 0.04). Secondary outcomes were seroma and hypoparathyroidism development. The risk of hypoparathyroidism did not differ between the FS and conventional groups (I = 0%, relative risk = 1.31, P = 0.38). Analysis of "seroma formation that required invasive treatment" indicated that FS showed some benefit (I2 = 8%, relative risk 0.44, P = 0.15). Heterogeneity among the different trials limited their conclusions. The meta-analysis showed that although FS use did not significantly reduce seroma or hypoparathyroidism incidence in patients after thyroidectomy, it significantly reduced the total drainage volume, length of hospitalization, and duration of surgery.


Assuntos
Adesivo Tecidual de Fibrina , Tireoidectomia , Humanos , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Adesivo Tecidual de Fibrina/uso terapêutico , Resultado do Tratamento , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Tempo de Internação/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Duração da Cirurgia , Adesivos Teciduais/uso terapêutico
8.
Phys Rev Lett ; 132(13): 130603, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613293

RESUMO

In the quest to build general-purpose photonic quantum computers, fusion-based quantum computation has risen to prominence as a promising strategy. This model allows a ballistic construction of large cluster states which are universal for quantum computation, in a scalable and loss-tolerant way without feed forward, by fusing many small n-photon entangled resource states. However, a key obstacle to this architecture lies in efficiently generating the required essential resource states on photonic chips. One such critical seed state that has not yet been achieved is the heralded three-photon Greenberger-Horne-Zeilinger (3-GHZ) state. Here, we address this elementary resource gap, by reporting the first experimental realization of a heralded 3-GHZ state. Our implementation employs a low-loss and fully programmable photonic chip that manipulates six indistinguishable single photons of wavelengths in the telecommunication regime. Conditional on the heralding detection, we obtain the desired 3-GHZ state with a fidelity 0.573±0.024. Our Letter marks an important step for the future fault-tolerant photonic quantum computing, leading to the acceleration of building a large-scale optical quantum computer.

9.
J Asian Nat Prod Res ; : 1-10, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634704

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive subtype with poor prognosis of breast cancer. Thiostrepton exerts anti-tumor activities against several cancers including TNBC. Herein we discussed the new molecular mechanisms of thiostrepton in TNBC. Thiostrepton inhibited MDA-MB-231 cell viability, accompanied by a decrease of c-FLIP and p-SMAD2/3. c-FLIP overexpression reduced the sensitivity of MDA-MB-231 cells to thiostrepton, while SMAD2/3 knockdown increased the sensitivity of MDA-MB-231 cells to thiostrepton. Moreover, c-FLIP overexpression significantly increased the expression and phosphorylation of SMAD2/3 proteins and vice versa. In conclusion, our study reveals c-FLIP/SMAD2/3 signaling pathway as a novel mechanism of antitumor activity of thiostrepton.

10.
Sci Total Environ ; 929: 172562, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641098

RESUMO

Poleward range expansion of marine organisms is commonly attributed to anthropogenic ocean warming. However, the extent to which a single species can migrate poleward remains unclear. In this study, we used molecular data to examine the current distribution of the Pocillopora damicornis species complex in Taiwan waters and applied niche modeling to predict its potential range through the end of the 21st Century. The P. damicornis species complex is widespread across shallow, tropical and subtropical waters of the Indo-Pacific regions. Our results revealed that populations from subtropical nonreefal coral communities are P. damicornis, whose native geographical ranges are approximately between 23°N and 35°N. In contrast, those from tropical reefs are P. acuta. Our analysis of 50 environmental data layers demonstrated that the concentrations of CaCO3 polymorphs had the greatest contributions to the distributions of the two species. Future projections under intermediate shared socioeconomic pathways (SSP) 2-4.5 and very high (SSP5-8.5) scenarios of greenhouse gas emissions showed that while sea surface temperature (SST) isotherms would shift northwards, saturation isolines of two CaCO3 polymorphs, calcite (Ωcal) and aragonite (Ωarag), would shift southwards by 2100. Subsequent predictions of future suitable habitats under those conditions indicated that distinct delimitation of geographical ranges for the two species would persist, and neither would extend beyond its native geographical zones, indicating that tropical Taiwan waters are the northern limit for P. acuta. In contrast, subtropical waters are the southern limit for P. damicornis. We concluded that the decline in CaCO3 saturation would make high latitudes less inhabitable, which could be one of the boundary elements that limit poleward range expansion driven by rising SSTs and preserve the latitudinal diversity gradient (LDG) on Earth. Consequently, poleward migration of tropical reef corals to cope with warming oceans should be reevaluated.

11.
Front Immunol ; 15: 1347901, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38571963

RESUMO

Most host-microbiota interactions occur within the intestinal barrier, which is essential for separating the intestinal epithelium from toxins, microorganisms, and antigens in the gut lumen. Gut inflammation allows pathogenic bacteria to enter the blood stream, forming immune complexes which may deposit on organs. Despite increased circulating immune complexes (CICs) in patients with inflammatory bowel disease (IBD) and discussions among IBD experts regarding their potential pathogenic role in extra-intestinal manifestations, this phenomenon is overlooked because definitive evidence demonstrating CIC-induced extra-intestinal manifestations in IBD animal models is lacking. However, clinical observations of elevated CICs in newly diagnosed, untreated patients with IBD have reignited research into their potential pathogenic implications. Musculoskeletal symptoms are the most prevalent extra-intestinal IBD manifestations. CICs are pivotal in various arthritis forms, including reactive, rheumatoid, and Lyme arthritis and systemic lupus erythematosus. Research indicates that intestinal barrier restoration during the pre-phase of arthritis could inhibit arthritis development. In the absence of animal models supporting extra-intestinal IBD manifestations, this paper aims to comprehensively explore the relationship between CICs and arthritis onset via a multifaceted analysis to offer a fresh perspective for further investigation and provide novel insights into the interplay between CICs and arthritis development in IBD.


Assuntos
Artrite , Doenças Inflamatórias Intestinais , Animais , Humanos , Complexo Antígeno-Anticorpo/uso terapêutico , Artrite/etiologia , Inflamação , Artralgia/etiologia
12.
World J Gastrointest Surg ; 16(2): 438-450, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463372

RESUMO

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR), a composite inflammatory biomarker, is associated with the prognosis in patients with colorectal tumors. However, whether the NLR can be used as a predictor of symptomatic postoperative anastomotic leakage (AL) in elderly patients with colon cancer is unclear. AIM: To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer. METHODS: Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed. Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR. Twenty-two covariates were matched using a 1:1 propensity score matching method, and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL. RESULTS: Of the 577 patients included, 36 (6.2%) had symptomatic AL. The optimal cutoff value of the NLR for predicting AL was 2.66. After propensity score matching, the incidence of AL was significantly greater in the ≥ 2.66 NLR subgroup than in the < 2.66 NLR subgroup (11.5% vs 2.5%; P = 0.012). Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoperatively, preoperative albumin concentration, preoperative prognostic nutritional index, and preoperative NLR and AL occurrence (P < 0.05); multivariate logistic regression analysis revealed that an NLR ≥ 2.66 [odds ratio (OR) = 5.51; 95% confidence interval (CI): 1.50-20.26; P = 0.010] and blood transfusion intraoperatively and within 2 d postoperatively (OR = 2.52; 95%CI: 0.88-7.25; P = 0.049) were risk factors for the occurrence of symptomatic AL. CONCLUSION: A preoperative NLR ≥ 2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer. The preoperative NLR has predictive value for postoperative symptomatic AL after elective surgery in elderly patients with colon cancer.

13.
World J Gastrointest Endosc ; 16(2): 91-97, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38464821

RESUMO

BACKGROUND: Benign rectal strictures can be categorized as primary (disease-related) and secondary (surgical anastomosis-related). Secondary strictures arise from surgical complications, whereas primary strictures have diverse etiologies, including various inflammatory conditions. Benign strictures are usually managed by surgery and endoscopy. We present an unusual etiology of benign rectal stricture caused by the repeated insertion of foreign objects into the rectum for sexual purposes, resulting in rectal injury and subsequent chronic inflammation. CASE SUMMARY: A 53-year-old man presented to the outpatient clinic of the Colorectal Surgery Department with symptoms of chronic constipation and bloody stools. The patient previously experienced rectal injury due to foreign object insertion for sexual purposes. Colonoscopy revealed benign circumferential narrowing of the rectum. He underwent treatment by endoscopic argon plasma coagulation and balloon dilation and follow-up as an outpatient for 4 months. A colonoscopy at the end of the follow-up period revealed no evidence of rectal stricture relapse. CONCLUSION: A history of rectal injury, followed by chronic inflammation, should be considered in patients with benign rectal strictures. Management with endoscopic argon plasma coagulation and balloon dilation can prevent the need for surgical resection of benign rectal strictures.

14.
BMC Infect Dis ; 24(Suppl 2): 334, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509486

RESUMO

BACKGROUND: Dengue fever is a well-studied vector-borne disease in tropical and subtropical areas of the world. Several methods for predicting the occurrence of dengue fever in Taiwan have been proposed. However, to the best of our knowledge, no study has investigated the relationship between air quality indices (AQIs) and dengue fever in Taiwan. RESULTS: This study aimed to develop a dengue fever prediction model in which meteorological factors, a vector index, and AQIs were incorporated into different machine learning algorithms. A total of 805 meteorological records from 2013 to 2015 were collected from government open-source data after preprocessing. In addition to well-known dengue-related factors, we investigated the effects of novel variables, including particulate matter with an aerodynamic diameter < 10 µm (PM10), PM2.5, and an ultraviolet index, for predicting dengue fever occurrence. The collected dataset was randomly divided into an 80% training set and a 20% test set. The experimental results showed that the random forests achieved an area under the receiver operating characteristic curve of 0.9547 for the test set, which was the best compared with the other machine learning algorithms. In addition, the temperature was the most important factor in our variable importance analysis, and it showed a positive effect on dengue fever at < 30 °C but had less of an effect at > 30 °C. The AQIs were not as important as temperature, but one was selected in the process of filtering the variables and showed a certain influence on the final results. CONCLUSIONS: Our study is the first to demonstrate that AQI negatively affects dengue fever occurrence in Taiwan. The proposed prediction model can be used as an early warning system for public health to prevent dengue fever outbreaks.


Assuntos
Dengue , Algoritmo Florestas Aleatórias , Humanos , Dengue/epidemiologia , Taiwan/epidemiologia , Temperatura , Surtos de Doenças
15.
NPJ Regen Med ; 9(1): 13, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519518

RESUMO

Neural progenitor cells (NPCs) derived from human pluripotent stem cells(hPSCs) provide major cell sources for repairing damaged neural circuitry and enabling axonal regeneration after spinal cord injury (SCI). However, the injury niche and inadequate intrinsic factors in the adult spinal cord restrict the therapeutic potential of transplanted NPCs. The Sonic Hedgehog protein (Shh) has crucial roles in neurodevelopment by promoting the formation of motorneurons and oligodendrocytes as well as its recently described neuroprotective features in response to the injury, indicating its essential role in neural homeostasis and tissue repair. In this study, we demonstrate that elevated SHH signaling in hNPCs by inhibiting its negative regulator, SUFU, enhanced cell survival and promoted robust neuronal differentiation with extensive axonal outgrowth, counteracting the harmful effects of the injured niche. Importantly, SUFU inhibition in NPCs exert non-cell autonomous effects on promoting survival and neurogenesis of endogenous cells and modulating the microenvironment by reducing suppressive barriers around lesion sites. The combined beneficial effects of SUFU inhibition in hNPCs resulted in the effective reconstruction of neuronal connectivity with the host and corticospinal regeneration, significantly improving neurobehavioral recovery in recipient animals. These results demonstrate that SUFU inhibition confers hNPCs with potent therapeutic potential to overcome extrinsic and intrinsic barriers in transplantation treatments for SCI.

16.
Heliyon ; 10(3): e25392, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356528

RESUMO

The recent attention garnered by Internet of Things (IoT) technology for its potential to alleviate challenges faced by healthcare systems, such as those resulting from an aging population and the rise in chronic illnesses, has underscored the significance of smart healthcare. Surprisingly, no bibliometric study has been conducted on this subject to date. Consequently, this investigation aims to provide a comprehensive overview of the longitudinal state and knowledge structure of IoT in smart healthcare. To achieve this, a content analysis tool is employed for academic research, facilitating the identification of key study themes, the growth trajectory of the research topic, the top journal sources, and the distribution of nations based on subject areas. The bibliometric evaluation encompasses 614 publications published in 14 journals spanning the period from 2016 to 2022. Employing bibliographic coupling analysis, the latest developments in IoT have been uncovered within the domain of smart healthcare. The findings reveal 11 primary research topic areas that have been the focus of scholarly discourse during this period. This study highlights that the computing paradigm and network connectivity emerge as the most prominent topics within this research domain. Blockchain-based security in healthcare closely follows as the second-largest topic discussed by scholars. Additionally, the analysis indicates a significant increase in total publications for the most popular topic, peaking around 2018.

17.
J Hazard Mater ; 468: 133840, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394897

RESUMO

Although numerous studies have reported the influencing factors of polycyclic aromatic hydrocarbons (PAHs) in surface soil from source, process or soil perspectives, the mechanism of PAHs heterogeneity in surface soil are still not well understood. In this study, the effects of 16 PAHs in surface soil of China sampled between 2003 and 2020 with their 17 "source-process-sink" factors at 1 km resolution (N = 660)) were explored using deep learning (eXtreme Gradient Boosting) to mine key information from complex dataset under the optimized parameters (i.e., learning rate = 0.05, maximum depth = 5, sub-sample = 0.8). It was observed that top five factors of 16 PAH had the largest cumulative contribution (i.e., from 84.8% to 98.1%) on their soil concentrations. PAH emission was the predominant driver, and its effect on soil PAH increases with increasing logKow. Soil was the second driver, in which clay can promote the partition of PAHs with low or middle logKow. However, sand can accumulate those congeners with high logKow. Moreover, the deep learning plus geo-statistical models (with low deviation for testing dataset (N = 283)) were capable of predicting soil PAH concentrations using their drivers with high accuracy. This study improved the understanding of the environmental fate and spatial variability of soil PAHs, as well as provided a novel technique (i.e., deep learning coupled with geo-statistics) for accurate prediction of soil pollutants.

18.
J Am Chem Soc ; 146(9): 6336-6344, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381858

RESUMO

Actuating materials convert different forms of energy into mechanical responses. To satisfy various application scenarios, they are desired to have rich categories, novel functionalities, clear structure-property relationships, fast responses, and, in particular, giant and reversible shape changes. Herein, we report a phase transition-driven ferroelectric crystal, (rac-3-HOPD)PbI3 (3-HOPD = 3-hydroxypiperidine cation), showing intriguingly large and anisotropic room-temperature actuating behaviors. The crystal consists of rigid one-dimensional [PbI3] anionic chains running along the a-axis and discrete disk-like cations loosely wrapping around the chains, leaving room for anisotropic shape changes in both the b- and c-axes. The shape change is switched by a ferroelectric phase transition occurring at around room temperature (294 K), driven by the exceptionally synergistic order-disorder and displacive phase transition. The rotation of the cations exerts internal pressure on the stacking structure to trigger an exceptionally large displacement of the inorganic chains, corresponding to a crystal lattice transformation with length changes of +24.6% and -17.5% along the b- and c-axis, respectively. Single crystal-based prototype devices of circuit switches and elevators have been fabricated by exploiting the unconventional negative temperature-dependent actuating behaviors. This work provides a new model for the development of multifunctional mechanically responsive materials.

19.
Zhongguo Zhong Yao Za Zhi ; 49(1): 197-207, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403352

RESUMO

This study aims to reveal the mechanism of prenatal stress in affecting the testicular development of offspring rats and the intervention effects of Zuogui Pills via connexin 43(Cx43). Forty pregnant SD rats were randomized into a blank control group, a mo-del group, a high-dose(18.9 g·kg~(-1)) Zuogui Pills group, a low-dose(9.45 g·kg~(-1)) Zuogui Pills group, and a vitamin E(1.44 mg·kg~(-1)) group. The other groups except the blank control group was subjected to chronic unpredictable mild stress for the modeling of prenatal stress. The model was evaluated by sucrose preference test, open field test, and enzyme-linked immunosorbent assay(ELISA) of the glucocorticoid level. ELISA was employed to measure the thyroxine 4(T4), testosterone(T), and follicle-stimulating hormone(FSH) levels to assess kidney deficiency. Hematoxylin-eosin(HE) staining was employed to evaluate the status of testicular germ cells. An automatic sperm analyzer was used to measure the sperm quality. Immunofluorescence double staining was employed to detect the expression of Cx43 and follicle-stimulating hormone receptor(FSHR) in the testes of offspring rats. The mRNA and protein levels of Cx43, FSHR, phosphatidylinositol 3-kinase(PI3K), and protein kinase B(Akt) were determined by real-time fluorescence quantitative polymerase chain reaction and Western blot, respectively. Prenatal stress induced testicular development disorders in offspring rats. The HE staining results showed that on the day of birth, the model group had reduced seminiferous tubules in the testes, elevated FSH level in the serum, and lowered Cx43 level in the testicular tissue. Male offspring rats of 60 days old had reduced testicular spermatogenic function, decreased sperm quality, elevated FSH level and lowered T level in the serum, and down-regulated protein and mRNA levels of Cx43, FSHR, PI3K, and Akt in the testicular tissue. Zuogui Pills alleviated the abnormal development and dysfunction of testicles in the offspring rats caused by prenatal stress. In summary, Zuogui Pills may weaken the effects of prenatal stress on testicular development and spermatogenic function of offspring rats by activating the PI3K/Akt pathway to regulate Cx43 expression in the testicular tissue.


Assuntos
Conexina 43 , Medicamentos de Ervas Chinesas , Proteínas Proto-Oncogênicas c-akt , Ratos , Masculino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Conexina 43/farmacologia , Ratos Sprague-Dawley , Fosfatidilinositol 3-Quinases/metabolismo , Sêmen/metabolismo , Testículo , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , RNA Mensageiro/metabolismo
20.
Nat Commun ; 15(1): 1464, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368439

RESUMO

Tuning phase transition temperature is one of the central issues in phase transition materials. Herein, we report a case study of using enantiomer fraction engineering as a promising strategy to tune the Curie temperature (TC) and related properties of ferroelectrics. A series of metal-halide perovskite ferroelectrics (S-3AMP)x(R-3AMP)1-xPbBr4 was synthesized where 3AMP is the 3-(aminomethyl)piperidine divalent cation and enantiomer fraction x varies between 0 and 1 (0 and 1 = enantiomers; 0.5 = racemate). With the change of the enantiomer fraction, the TC, second-harmonic generation intensity, degree of circular polarization of photoluminescence, and photoluminescence intensity of the materials have been tuned. Particularly, when x = 0.70 - 1, a continuously linear tuning of the TC is achieved, showing a tunable temperature range of about 73 K. This strategy provides an effective means and insights for regulating the phase transition temperature and chiroptical properties of functional materials.

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