Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 451
Filtrar
1.
Sci Total Environ ; 954: 176666, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378950

RESUMO

Satellite-derived products and field measurements verify that Tibetan Plateau (TP) has been experiencing continuous vegetation greening and productivity increase; however, it remains unclear how this greening translates into productivity and how long-term productivity variations depend on greenness across the TP. Moreover, ignoring the accuracy evaluation of satellite-derived greenness and productivity products may mislead the understanding of TP vegetation changes. Thus, we initially assessed the accuracy of three widely used leaf area index (LAI, proxy of greenness) products (i.e., MODIS, GLASS and GEOV2 LAI) and three gross primary productivity (GPP, proxy of productivity) products (i.e., MODIS, GLASS and PML-V2 GPP) to selected robust products to represent greenness and productivity respectively. Then, we explored the dependence of spatiotemporal GPP dynamics on greenness variations during 2000-2020. Results indicated that PML-V2 GPP and MODIS LAI were more robust and reliable than other satellite-derived products when compared to the reference values. They revealed a prevailing increase in GPP over the past two decades, with a regional average of 71 % higher than that of LAI. Notably, the area proportion of significant productivity enhancement was 31.6 % higher than that of significant greening. About 24.7 % of the TP displayed significantly inconsistent trends. The dependency of GPP on LAI gradually decreased with the increasing water availability, the complexity of vegetation structures, and dense canopy community. By calculating leaf photosynthetic capacity, we found that this indicator greatly regulated the velocity discrepancy between GPP and LAI, and the contribution of only greening to productivity is limited, only occupying 11.9 % of the TP, which was helpful in understanding the inter-annual changes of vegetation dynamics under varying environment conditions. We therefore reveal an unexpected rapid increase in productivity than greening during 2000-2020 on the TP, as well as highlight the caution of only using satellite-derived greenness indicators for assessing long-term changes in vegetation productivity dynamics, especially over mesic ecosystems with complex vegetation structures and dense canopies of TP.

2.
J Environ Manage ; 370: 122462, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39270342

RESUMO

The potential of forestation to mitigate climate warming depends largely on whether it can improve terrestrial carbon (C) storage. Changes in soil microbial stability can cause ecosystem C fluctuations. Unfortunately, it remains unclear whether forestation alters soil microbial stability with cascading effects on C storage in high-altitude ecosystems. In this study, a total of 14 typical planted forests were selected on the Tibetan Plateau. We showed that high-altitude forestation, particularly with poplars, altered the microbial diversity and potentially improved the stability of soil microbial communities. These changes were associated with soil C accumulation and potentially positive feedback on soil organic C storage. Variations in the microbial community stability were mostly caused by changes in soil bulk density and dissolved organic C. Superior network stability was found in fungal community rather than bacterial community. Additionally, there were strong interactions between bacterial and fungal communities that influenced soil C storage. These findings contribute to understand the differences and relationships between bacteria and fungi in plantation soils. This work reveals the potential of high-altitude forestation to mitigate climate warming through insights into the microbial-mediated mechanisms responsible for soil C storage in high-altitude ecosystems.

3.
Adv Sci (Weinh) ; : e2402643, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137163

RESUMO

Turbulent flows are observed in low-Reynolds active fluids, which display similar phenomenology to the classical inertial turbulence but are of a different nature. Understanding the dependence of this new type of turbulence on dimensionality is a fundamental challenge in non-equilibrium physics. Real-space structures and kinetic energy spectra of bacterial turbulence are experimentally measured from two to three dimensions. The turbulence shows three regimes separated by two critical confinement heights, resulting from the competition of bacterial length, vortex size and confinement height. Meanwhile, the kinetic energy spectra display distinct universal scaling laws in quasi-2D and 3D regimes, independent of bacterial activity, length, and confinement height, whereas scaling exponents transition in two steps around the critical heights. The scaling behaviors are well captured by the hydrodynamic model we develop, which employs image systems to represent the effects of confining boundaries. The study suggests a framework for investigating the effect of dimensionality on non-equilibrium self-organized systems.

4.
Phys Rev Lett ; 133(4): 048302, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39121428

RESUMO

Direct mechanical coupling is known to be critical for establishing synchronization among cilia. However, the actual role of the connections is still elusive-partly because controlled experiments in living samples are challenging. Here, we employ an artificial ciliary system to address this issue. Two cilia are formed by chains of self-propelling robots and anchored to a shared base so that they are purely mechanically coupled. The system mimics biological ciliary beating but allows fine control over the beating dynamics. With different schemes of mechanical coupling, artificial cilia exhibit rich motility patterns. Particularly, their synchronous beating display two distinct modes-analogous to those observed in C. reinhardtii, the biciliated model organism for studying synchronization. Close examination suggests that the system evolves towards the most dissipative mode. Using this guideline in both simulations and experiments, we are able to direct the system into a desired state by altering the modes' respective dissipation. Our results have significant implications in understanding the synchronization of cilia.


Assuntos
Biomimética , Cílios , Robótica , Cílios/fisiologia , Biomimética/métodos , Modelos Biológicos , Chlamydomonas reinhardtii/fisiologia
5.
Neurol Sci ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39098857

RESUMO

PURPOSE: Angiocentric glioma (AG), a benign tumor identified within the last two decades, was officially included in the 2007 WHO Classification of Tumors of the Central Nervous System, WHO grade I. The tumor is relatively rare, with only approximately 100 cases reported. We aim to complement the characteristics and long-term prognosis of AG, as well as to detect MYB-QKI fusions. METHODS: The characteristics of all cases collected between 1 March 2009 and 1 March 2023 at the Beijing Sanbo Brain Hospital, Capital Medical University, were summarized and analyzed. Additionally, all fourteen patients were tested for MYB-QKI fusions. RESULTS: AG more predominantly occurs in adolescents (median age 16.5-year-old), and commonly presents with drug-resistant epilepsy. AG is frequently localized in the supratentorial regions and only one patient is in the brainstem. Brain parenchyma atrophy, and stalk-like signs can observe in imaging. Pathologically, tumor cells are perivascular pseudorosettes, presenting immunoreactivity for GFAP, S-100, Vimentin, "dot-like" staining for EMA, and low proliferative activity. Focal cortex dysplasia was observed in four patients. Twelve of fourteen (85.7%) patients were found with MYB-QKI fusions. Completely surgical resection typically has a satisfactory prognosis with long-term follow-up. CONCLUSION: AG is a rare benign tumor with a favorable prognosis after complete resection, characterized by refractory epilepsy, frequently occurring in adolescents. MYB-QKI fusions were detected in most AG patients, as a good defining genetic alteration pathologically. The potential presence of focal cortical dysplasia (FCD) may affect the prognosis of epilepsy.

6.
World J Gastrointest Surg ; 16(6): 1791-1802, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38983329

RESUMO

BACKGROUND: Metastatic colorectal cancer (mCRC) is a common malignancy whose treatment has been a clinical challenge. Cancer-specific survival (CSS) plays a crucial role in assessing patient prognosis and treatment outcomes. However, there is still limited research on the factors affecting CSS in mCRC patients and their correlation. AIM: To predict CSS, we developed a new nomogram model and risk grading system to classify risk levels in patients with mCRC. METHODS: Data were extracted from the United States Surveillance, Epidemiology, and End Results database from 2018 to 2023. All eligible patients were randomly divided into a training cohort and a validation cohort. The Cox proportional hazards model was used to investigate the independent risk factors for CSS. A new nomogram model was developed to predict CSS and was evaluated through internal and external validation. RESULTS: A multivariate Cox proportional risk model was used to identify independent risk factors for CSS. Then, new CSS columns were developed based on these factors. The consistency index (C-index) of the histogram was 0.718 (95%CI: 0.712-0.725), and that of the validation cohort was 0.722 (95%CI: 0.711-0.732), indicating good discrimination ability and better performance than tumor-node-metastasis staging (C-index: 0.712-0.732). For the training set, 0.533, 95%CI: 0.525-0.540; for the verification set, 0.524, 95%CI: 0.513-0.535. The calibration map and clinical decision curve showed good agreement and good potential clinical validity. The risk grading system divided all patients into three groups, and the Kaplan-Meier curve showed good stratification and differentiation of CSS between different groups. The median CSS times in the low-risk, medium-risk, and high-risk groups were 36 months (95%CI: 34.987-37.013), 18 months (95%CI: 17.273-18.727), and 5 months (95%CI: 4.503-5.497), respectively. CONCLUSION: Our study developed a new nomogram model to predict CSS in patients with synchronous mCRC. In addition, the risk-grading system helps to accurately assess patient prognosis and guide treatment.

7.
ACS Appl Mater Interfaces ; 16(28): 36289-36294, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954646

RESUMO

Na-O2 batteries have emerged as promising candidates due to their high theoretical energy density (1,601 Wh kg-1), the potential for high energy storage efficiency, and the abundance of sodium in the earth's crust. Considering the safety issue, quasi-solid-state composite polymer electrolytes are among the promising solid-state electrolyte candidates. Their higher mechanical toughness provides superior resistance to dendritic penetration compared with traditional liquid electrolytes. The flexibility of the composite polymer electrolyte matrix allows it to conform to various battery configurations and considerably reduces safety concerns related to the combustion risks associated with conventional liquid electrolytes. In this study, we employed poly(ethylene oxide) (PEO) and sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) as the polymer matrix and sodium ion-conducting agent, respectively. We incorporated nanosized NZSP (25 wt %) to create the composite polymer electrolyte membrane. This CPE design facilitates ion conduction pathways through both sodium salt and NZSP. By utilizing a liquid electrolyte infiltration method, we successfully enhanced its ionic conductivity, achieving an ionic conductivity of 10-4 S cm-1 at room temperature.

8.
World J Microbiol Biotechnol ; 40(7): 232, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38834810

RESUMO

Microbially induced carbonate precipitation (MICP) has been used to cure rare earth slags (RES) containing radionuclides (e.g. Th and U) and heavy metals with favorable results. However, the role of microbial extracellular polymeric substances (EPS) in MICP curing RES remains unclear. In this study, the EPS of Lysinibacillus sphaericus K-1 was extracted for the experiments of adsorption, inducing calcium carbonate (CaCO3) precipitation and curing of RES. The role of EPS in in MICP curing RES and stabilizing radionuclides and heavy metals was analyzed by evaluating the concentration and morphological distribution of radionuclides and heavy metals, and the compressive strength of the cured body. The results indicate that the adsorption efficiencies of EPS for Th (IV), U (VI), Cu2+, Pb2+, Zn2+, and Cd2+ were 44.83%, 45.83%, 53.7%, 61.3%, 42.1%, and 77.85%, respectively. The addition of EPS solution resulted in the formation of nanoscale spherical particles on the microorganism surface, which could act as an accumulating skeleton to facilitate the formation of CaCO3. After adding 20 mL of EPS solution during the curing process (Treat group), the maximum unconfined compressive strength (UCS) of the cured body reached 1.922 MPa, which was 12.13% higher than the CK group. The contents of exchangeable Th (IV) and U (VI) in the cured bodies of the Treat group decreased by 3.35% and 4.93%, respectively, compared with the CK group. Therefore, EPS enhances the effect of MICP curing RES and reduces the potential environmental problems that may be caused by radionuclides and heavy metals during the long-term sequestration of RES.


Assuntos
Bacillaceae , Carbonato de Cálcio , Matriz Extracelular de Substâncias Poliméricas , Metais Pesados , Tório , Urânio , Urânio/química , Urânio/metabolismo , Carbonato de Cálcio/química , Tório/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Matriz Extracelular de Substâncias Poliméricas/química , Bacillaceae/metabolismo , Metais Terras Raras/química , Adsorção , Precipitação Química
9.
Beilstein J Nanotechnol ; 15: 664-677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887525

RESUMO

Hair, or hair-like fibrillar structures, are ubiquitous in biology, from fur on the bodies of mammals, over trichomes of plants, to the mastigonemes on the flagella of single-celled organisms. While these long and slender protuberances are passive, they are multifunctional and help to mediate interactions with the environment. They provide thermal insulation, sensory information, reversible adhesion, and surface modulation (e.g., superhydrophobicity). This review will present various functions that biological hairs have been discovered to carry out, with the hairs spanning across six orders of magnitude in size, from the millimeter-thick fur of mammals down to the nanometer-thick fibrillar ultrastructures on bateriophages. The hairs are categorized according to their functions, including protection (e.g., thermal regulation and defense), locomotion, feeding, and sensing. By understanding the versatile functions of biological hairs, bio-inspired solutions may be developed across length scales.

10.
Cancer Manag Res ; 16: 491-505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800665

RESUMO

Purpose: We aimed to develop a nomogram to predict prognosis of HR+ HER2- breast cancer patients and guide the application of postoperative adjuvant chemotherapy. Methods: We identified 310 eligible HR+ HER- breast cancer patients and randomly divided the database into a training group and a validation group. The endpoint was disease free survival (DFS). Concordance index (C-index), area under the curve (AUC) and calibration curves were used to evaluate predictive accuracy and discriminative ability of the nomogram. We also compared the predictive accuracy and discriminative ability of our nomogram with the eighth AJCC staging system using overall data. Results: According to the training group, platelet-to-lymphocyte ratio (PLR), tumor size, positive lymph nodes and Ki-67 index were used to construct the nomogram of DFS. The C-index of DFS was 0.708 (95% CI: 0.623-0.793) in the training group and 0.67 (95% CI: 0.544-0.796) in the validation group. The calibration curves revealed great consistencies in both groups. Conclusion: We have developed and validated a novel and practical nomogram that can provide individual prediction of DFS for patients with HR+ HER- breast cancer. This nomogram may help clinicians in risk consulting and guiding the application of postoperative adjuvant chemotherapy.

11.
Cell Biol Toxicol ; 40(1): 37, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777957

RESUMO

Bisphenol A (BPA) is a common component in the manufacture of daily plastic consumer goods. Recent studies have suggested that prenatal exposure to BPA can increase the susceptibility of offspring to mental illness, although the underlying mechanisms remain unclear. In this study, we performed transcriptomic and epigenomic profiling in the adult mouse brain following prenatal exposure to low-dose BPA. We observed a sex-specific transcriptional dysregulation in the cortex, with more significant differentially expressed genes was observed in adult cortex from male offspring. Moreover, the upregulated genes primarily influenced neuronal functions, while the downregulated genes were significantly associated with energy metabolism pathways. More evidence supporting impaired mitochondrial function included a decreased ATP level and a reduced number of mitochondria in the cortical neuron of the BPA group. We further investigated the higher-order chromatin regulatory patterns of DEGs by incorporating published Hi-C data. Interestingly, we found that upregulated genes exhibited more distal interactions with multiple enhancers, while downregulated genes displayed relatively short-range interactions among adjacent genes. Our data further revealed decreased H3K9me3 signal on the distal enhancers of upregulated genes, whereas increased DNA methylation and H3K27me3 signals on the promoters of downregulated genes. In summary, our study provides compelling evidence for the potential health risks associated with prenatal exposure to BPA, and uncovers sex-specific transcriptional changes with a complex interplay of multiple epigenetic mechanisms.


Assuntos
Compostos Benzidrílicos , Encéfalo , Metilação de DNA , Epigênese Genética , Fenóis , Efeitos Tardios da Exposição Pré-Natal , Animais , Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Epigênese Genética/efeitos dos fármacos , Masculino , Camundongos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Camundongos Endogâmicos C57BL
12.
Elife ; 132024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752724

RESUMO

Eukaryotes swim with coordinated flagellar (ciliary) beating and steer by fine-tuning the coordination. The model organism for studying flagellate motility, Chlamydomonas reinhardtii, employs synchronous, breaststroke-like flagellar beating to swim, and it modulates the beating amplitudes differentially to steer. This strategy hinges on both inherent flagellar asymmetries (e.g. different response to chemical messengers) and such asymmetries being effectively coordinated in the synchronous beating. In C. reinhardtii, the synchrony of beating is known to be supported by a mechanical connection between flagella; however, how flagellar asymmetries persist in the synchrony remains elusive. For example, it has been speculated for decades that one flagellum leads the beating, as its dynamic properties (i.e. frequency, waveform, etc.) appear to be copied by the other one. In this study, we combine experiments, computations, and modeling efforts to elucidate the roles played by each flagellum in synchronous beating. With a non-invasive technique to selectively load each flagellum, we show that the coordinated beating essentially only responds to load exerted on the cis flagellum; and that such asymmetry in response derives from a unilateral coupling between the two flagella. Our results highlight a distinct role for each flagellum in coordination and have implication for biflagellates' tactic behaviors.


Many single-cell organisms use tiny hair-like structures called flagella to move around. To direct this movement, the flagella must work together and beat in a synchronous manner. In some organisms, coordination is achieved by each flagellum reacting to the flow generated by neighbouring flagella. In others, flagella are joined together by fiber connections between their bases, which allow movement to be coordinated through mechanical signals sent between flagella. One such organism is Chlamydomonas reinhardtii, a type of algae frequently used to study flagellar coordination. Its two flagella ­ named trans and cis because of their positions relative to the cell's eyespot ­ propel the cell through water using breaststroke-like movements. To steer, C. reinhardtii adjusts the strength of the strokes made by each flagellum. Despite this asymmetry, the flagella must continue to beat in synchrony to move efficiently. To understand how the cell manages these differences, Wei et al. exposed each flagellum to carefully generated oscillations in water so that each was exposed to different forces and their separate responses could be measured. A combination of experiments, modelling and computer simulations were then used to work out how the two flagella coordinate to steer the cell. Wei et al. found that only the cis flagellum coordinates the beating, with the trans flagellum simply copying the motion of the cis. A direct consequence of such one-way coupling is that only forces on the cis flagellum influence the coordinated beating dynamics of both flagella. These findings shed light on the unique roles of each flagellum in the coordinated movement in C. reinhardtii and have implications for how other organisms with mechanically-connected flagella navigate their environments.


Assuntos
Chlamydomonas reinhardtii , Flagelos , Chlamydomonas reinhardtii/fisiologia , Flagelos/fisiologia
14.
Curr Pharm Des ; 30(19): 1530-1540, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38676524

RESUMO

BACKGROUND: Bear Bile Powder (BBP) is a traditional Chinese medicine. It has been widely used in clinical practices and has shown a good anti-inflammatory effect. However, its effectiveness in treating Ulcerative Colitis (UC) has not yet been studied. OBJECTIVE: To explore the therapeutic effect of BBP on ulcerative colitis and its potential mechanism by combining acute ulcerative colitis mouse models and comprehensively observing various physiological and biochemical indexes of mice. METHODS: The acute ulcerative colitis model was induced by drinking water containing dextran sulfate sodium salt (DSS) for 7 days. Studies were divided into Control, DSS, DSS+ Sulfasalazine (SASP, 450 mg/kg), and DSS + bear bile powder group (BBP, 320 mg/kg). The Disease Activity Index (DAI) and colonic tissue damage of mice were evaluated. Tissue immunofluorescence and western blot were used to determine related tight Junction Proteins (TJs), and 16S V34 amplicon was used to analyze intestinal microorganisms. The therapeutic effect of BBP on ulcerative colitis model mice was studied comprehensively. RESULTS: After treatment, BBP can significantly improve the physiological condition of acute UC mice and reduce DAI fraction. Compared with the DSS group, the BBP group significantly increased the colon length and significantly decreased the injury fraction of acute UC mice. Regarding the intestinal mechanical barrier, BBP significantly increased the expression of ZO-1, Occludin, and Claudin 1 protein in colon tissue. In terms of microbial community, the intestinal microbial diversity of mice decreased after the administration of BBP, but there was no significant difference in structural composition between the BBP group and the Control group. By comparing the four groups of species with significant differences, it was found that the BBP group significantly reduced the abundance of specific harmful microorganisms at the order, family, genus, and species levels. CONCLUSION: Oral administration of a certain dose of BBP can significantly improve the symptoms of ulcerative colitis in mice. Part of the reason may be that it increases the expression of tight junction proteins, regulates specific flora in the intestine of mice, and maintains intestinal barrier homeostasis. In the future, the clinical application value of BBP will be explored, and BBP will be developed as a drug with the potential to treat UC and alleviate the pain of UC patients.


Assuntos
Colite Ulcerativa , Sulfato de Dextrana , Modelos Animais de Doenças , Microbioma Gastrointestinal , Pós , Ursidae , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/induzido quimicamente , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Bile/metabolismo , Bile/química , Camundongos Endogâmicos C57BL , Medicina Tradicional Chinesa
15.
Nat Commun ; 15(1): 2489, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509103

RESUMO

The elevation gradient has long been known to be vital in shaping the structure and function of terrestrial ecosystems, but little is known about the elevation-dependent pattern of net CO2 uptake, denoted by net ecosystem productivity (NEP). Here, by analyzing data from 203 eddy covariance sites across China, we report a negative linear elevation-dependent pattern of NEP, collectively shaped by varying hydrothermal factors, nutrient supply, and ecosystem types. Furthermore, the NEP shows a higher temperature sensitivity in high-elevation environments (3000-5000 m) compared with the lower-elevation environments (<3000 m). Model ensemble and satellite-based observations consistently reveal more rapid relative changes in NEP in high-elevation environments during the last four decades. Machine learning also predicts a stronger relative increase in high-elevation environments, whereas less change is expected at lower elevations. We therefore conclude a varying elevation-dependent pattern of the NEP of terrestrial ecosystems in China, although there is significant uncertainty involved.


Assuntos
Dióxido de Carbono , Ecossistema , Temperatura , Temperatura Alta , China
16.
Medicine (Baltimore) ; 103(4): e36924, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277562

RESUMO

BACKGROUND: One of the risk factors for esophageal adenocarcinoma is achalasia, an esophageal motility disorder that is typically treated surgically through laparotomy or laparoscopic surgery. The risk factors of gastric cardia cancer are also similar to esophageal adenocarcinoma due to the anatomical location of the gastric cardia close to the esophagus. There is currently no clinical evidence that achalching has a correlation with gastric cardia cancer. CASE SUMMARY: We report the case of an 85-year-old female patient was admitted to our department with dysphagia for 6 months. She underwent a dissecting Heller myotomy for pancreatic achalasia in 2006, with occasional postoperative symptoms of reflux and heartburn. Outpatient upper gastrointestinal imaging was suggestive of cardia cancer, and gastroscopic pathological findings were suggestive of moderately-lowly-differentiated adenocarcinoma. The patient was admitted to the operating room on August 30, 2022 to undergo radical pancreatic cancer surgery plus abdominal adhesion release, and postoperative review of the upper gastrointestinal imaging showed a patent anastomosis with no spillage, filling of the residual stomach, and duodenal visualization. CONCLUSION: Postoperative patients with achalasia often have symptoms of reflux, which may be one of the factors for the development of pancreatic cancer in this patient, thus requiring clinicians to pay more attention to the use of antireflux procedures in the surgical treatment of pancreatic achalasia. And the choice of which modality to perform surgery in patients with previous surgical history is also one of the points to be discussed.


Assuntos
Carcinoma , Cárdia , Acalasia Esofágica , Neoplasias Gástricas , Idoso de 80 Anos ou mais , Feminino , Humanos , Adenocarcinoma/diagnóstico , Carcinoma/diagnóstico , Acalasia Esofágica/cirurgia , Refluxo Gastroesofágico/etiologia , Miotomia de Heller/métodos , Laparoscopia/métodos , Neoplasias Pancreáticas/cirurgia , Neoplasias Gástricas/diagnóstico , Resultado do Tratamento
17.
Acta Radiol ; 65(5): 406-413, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38196245

RESUMO

BACKGROUND: Surveillance of pancreatic cysts are necessary due to risk of malignant transformation. However, reported progression rates to advanced neoplasia are variable and the high frequency of surveillance scans may pose a considerable burden on healthcare resources. PURPOSE: To validate the effectiveness of the Fukuoka Guidelines surveillance regime and determine if a longer surveillance interval can be established. MATERIAL AND METHODS: All magnetic resonance imaging (MRI) studies of the pancreas performed at our institution between January 2014 and December 2016 with at least one pancreatic cystic lesion and follow-up MRI or computed tomography (CT) over at least two years were reviewed for size, worrisome feature (WF), and high-risk stigmata (HRS) at diagnosis and follow-up imaging (up to year 6). Reference standards for advanced neoplasia were based on endoscopic ultrasound, fine needle aspiration cytology, or the presence of ≥2 WF or ≥1 HRS on imaging. Comparison of MRI features of progression and outcomes of diagnostic endpoints between lesions <20 mm and ≥20 mm was performed. RESULTS: A total of 270 patients were included (201 cysts <20 mm, 69 cysts ≥20 mm). Compared with cysts <20 mm, cysts ≥20 mm were more likely to be associated with WF or HRS (40.6% vs. 12.4%; P ≤0.00001), demonstrate increase in size of ≥5 mm in two years (20.3% vs. 10.9%; P = 0.049), and develop advanced neoplasia (24.6% vs. 0.5%; P <0.00001). CONCLUSION: Pancreatic cysts <20 mm have a low risk of developing WF and HRS and surveillance interval may be lengthened.


Assuntos
Imageamento por Ressonância Magnética , Cisto Pancreático , Tomografia Computadorizada por Raios X , Humanos , Cisto Pancreático/diagnóstico por imagem , Cisto Pancreático/patologia , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Adulto , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Progressão da Doença , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Idoso de 80 Anos ou mais , Fatores de Tempo
18.
BMC Pediatr ; 24(1): 51, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229006

RESUMO

OBJECTIVE: The study aimed to explore the effectiveness of bedside lung ultrasound (LUS) combined with the PaO2/FiO2 (P/F) ratio in evaluating the outcomes of high-flow nasal cannula (HFNC) therapy in infants with severe pneumonia. METHODS: This retrospective study analyzed the clinical data of 150 infants diagnosed with severe pneumonia and treated with HFNC therapy at our hospital from January 2021 to December 2021. These patients were divided into two groups based on their treatment outcomes: the HFNC success group (n = 112) and the HFNC failure group (n = 38). LUS was utilized to evaluate the patients' lung conditions, and blood gas results were recorded for both groups upon admission and after 12 h of HFNC therapy. RESULTS: At admission, no significant differences were observed between the two groups in terms of age, gender, respiratory rate, partial pressure of oxygen, and partial pressure of carbon dioxide. However, the P/F ratios at admission and after 12 h of HFNC therapy were significantly lower in the HFNC failure group (193.08 ± 49.14, 228.63 ± 80.17, respectively) compared to the HFNC success group (248.51 ± 64.44, 288.93 ± 57.17, respectively) (p < 0.05). Likewise, LUS scores at admission and after 12 h were significantly higher in the failure group (18.42 ± 5.3, 18.03 ± 5.36, respectively) than in the success group (15.09 ± 4.66, 10.71 ± 3.78, respectively) (p < 0.05). Notably, in the success group, both P/F ratios and LUS scores showed significant improvement after 12 h of HFNC therapy, a trend not observed in the failure group. Multivariate regression analysis indicated that lower P/F ratios and higher LUS scores at admission and after 12 h were predictive of a greater risk of HFNC failure. ROC analysis demonstrated that an LUS score > 20.5 at admission predicted HFNC therapy failure with an AUC of 0.695, a sensitivity of 44.7%, and a specificity of 91.1%. A LUS score > 15.5 after 12 h of HFNC therapy had an AUC of 0.874, with 65.8% sensitivity and 89.3% specificity. An admission P/F ratio < 225.5 predicted HFNC therapy failure with an AUC of 0.739, 60.7% sensitivity, and 71.1% specificity, while a P/F ratio < 256.5 after 12 h of HFNC therapy had an AUC of 0.811, 74.1% sensitivity, and 73.7% specificity. CONCLUSION: Decreased LUS scores and increased P/F ratio demonstrate a strong correlation with successful HFNC treatment outcomes in infants with severe pneumonia. These findings may provide valuable support for clinicians in managing such cases.


Assuntos
Pneumonia , Insuficiência Respiratória , Lactente , Humanos , Cânula , Estudos Retrospectivos , Oxigenoterapia/métodos , Pulmão/diagnóstico por imagem , Pneumonia/diagnóstico por imagem , Pneumonia/terapia , Oxigênio , Insuficiência Respiratória/terapia
19.
J Magn Reson Imaging ; 59(3): 954-963, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37312270

RESUMO

BACKGROUND: Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in human brains, playing a role in the pathogenesis of various psychiatric disorders. Current methods have some non-neglectable shortcomings and noninvasive and accurate detection of GABA in human brains is long-term challenge. PURPOSE: To develop a pulse sequence capable of selectively detecting and quantifying the 1 H signal of GABA in human brains based on optimal controlled spin singlet order. STUDY TYPE: Prospective. SUBJECTS/PHANTOM: A phantom of GABA (pH = 7.3 ± 0.1) and 11 healthy subjects (5 females and 6 males, body mass index: 21 ± 3 kg/m2 , age: 25 ± 4 years). FIELD STRENGTH/SEQUENCE: 7 Tesla, 3 Tesla, GABA-targeted magnetic resonance spectroscopy (GABA-MRS-7 T, GABA-MRS-3 T), magnetization prepared two rapid acquisition gradient echoes sequence. ASSESSMENT: By using the developed pulse sequences applied on the phantom and healthy subjects, the signals of GABA were successfully selectively probed. Quantification of the signals yields the concentration of GABA in the dorsal anterior cingulate cortex (dACC) in human brains. STATISTICAL TESTS: Frequency. RESULTS: The 1 H signals of GABA in the phantom and in the human brains of healthy subjects were successfully detected. The concentration of GABA in the dACC of human brains was 3.3 ± 1.5 mM. DATA CONCLUSION: The developed pulse sequences can be used to selectively probe the 1 H MR signals of GABA in human brains in vivo. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Estudos Prospectivos , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico
20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1017249

RESUMO

Objective To investigate the role of heme oxygenase-1(HO-1)on HBV replication and the antiviral effect of HO-1 combined with α-interferon(IFN-α).Methods HepG2.2.15 cells and HBV1.3-transfected HepG2 cells(HepG2-HBV1.3)were used as HBV replicating cell models;Hemin treated HepG2.2.15 and HepG2-HBV1.3 cells,to induce the expression of HO-1 molecules.CCK-8 method was used to assess the toxic effects of Hemin on HepG2 and HepG2.2.15;chemiluminescence method was used to analyze HBsAg and HBeAg in the supernatants of Hemin-treated group and si-HO-1 and other experimental groups;RT-qPCR was used to ana-lyze HO-1,IFN-β and HBV-DNA;Western blot was used to analyze the expression of IRF-3 and the expression of related molecules in the JAK/STAT signaling pathway;Hemin combined with IFN-α treated HepG2.2.15 to moni-tor whether HO-1 had synergistic IFN-α antiviral effect.Results Hemin dose-dependently induced HO-1,and HO-1 was induced to exert a significant anti-HBV effect,while the expression of IFN-β,IRF-3,and IRF-9 and MxA,downstream molecules of the JAK/STAT signaling pathway,were all increased.Silencing HO-1 expression reversed the antiviral effect in the Hemin-induced group,and at the same time,type Ⅰ interferon IFN-β showed low expression,and the expression of IRF-9 and MxA in the JAK/STAT signaling pathway was inhibited as well.He-min combined with IFN-α exerted stronger antiviral effects.Conclusion HO-1 can exert an anti-HBV effect,which may be due to increased phosphorylation of IRF-3 to induce type Ⅰ interferon expression and thus activate the JAK/STAT signaling pathway to exert an antiviral effect;HO-1 can synergize with IFN-α to exert an antiviral effect.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA