Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 247
Filtrar
1.
Ann Surg Oncol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969851

RESUMO

BACKGROUND: Current guidelines recommend against the use of routine imaging tests to detect distant metastasis in asymptomatic breast cancer patients. However, recent advancements in effective therapeutics and diagnostic accuracy have raised the need to reassess the clinical efficacy of intensive metastasis surveillance. We report the results of a multicenter retrospective study to investigate the association between intensive imaging studies and survival outcomes. PATIENTS AND METHODS: We retrospectively reviewed the data of 4130 patients who underwent surgery from 11 hospitals in Korea between January 2010 and December 2011. Patients were divided into two groups on the basis of the intensity of metastasis imaging studies during their disease-free period. The types and intervals of the imaging studies were based on each physician's decisions. RESULTS: High-intensive screening showed a shorter distant metastasis-free survival [p < 0.001, hazard ratio (HR) 1.62; 95% confidence interval (CI) 1.29-2.04], especially for patients in whom bone or lung was the first site of metastasis. With a median follow-up period of 110.0 months, the 5-year breast cancer-specific survival (BCSS) rate was 96.5%. The high-intensity screening group showed significantly poorer BCSS compared with the low-intensity screening group (p < 0.001, HR 3.13; 95% CI 2.32-4.21). However, both multivariable analysis and propensity score matching analysis showed no significant association between the screening intensity and BCSS. CONCLUSIONS: Frequent imaging studies to detect distant metastasis were associated with earlier detection of distant metastasis, especially for lung and bone metastasis. However, intensive surveillance showed no apparent association with BCSS despite the use of currently available treatments.

2.
BMC Geriatr ; 24(1): 579, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965464

RESUMO

BACKGROUND: With an increasing proportion of older adults and the associated risk of Alzheimer's Disease and Related Dementias (ADRD) around the globe, there is an urgent need to engage in ADRD risk reduction efforts. African American (AA) older adults in the U.S. are disproportionally impacted by ADRD compared to other races and ethnicities. Mindful walking integrates two potentially protective factors of ADRD by elevating mindfulness and physical activity (i.e., walking), resulting in a synergistic behavioral strategy that is feasible and safe for older adults. However, the efficacy of applying this intervention for cognitive health outcomes has not been evaluated using experimental designs. METHODS: This paper documents the goal and protocol of a community-based, mindful walking randomized controlled trial to examine the short- and longer-term efficacy on cognitive and other health-related outcomes in ADRD at-risk AA older adults. The study outcomes include various brain health determinants, including cognitive function, quality of life, psychological well-being, physical activity, mindfulness, sleep, and overall health status. In addition, the estimated costs of program implementation are also collected throughout the study period. This study will recruit 114 older adults (ages 60+ years) with elevated ADRD risk from the Midlands region of South Carolina. Older adults are randomly assigned to participate in 24 sessions of outdoor mindful walking over three months or a delayed mindful walking group (n=57 in each group). Participants in both groups follow identical measurement protocols at baseline, after 12 weeks, after 18 weeks, and after 24 weeks from baseline. The outcome measures are administered in the lab and in everyday settings. Costs per participant are calculated using micro-costing methods. The eliciting participant costs for mindful walking engagement with expected results are reported using the payer and the societal perspectives. DISCUSSION: This study will generate evidence regarding the efficacy of mindful walking on sustaining cognitive health in vulnerable older adults. The results can inform future large-scale effectiveness trials to support our study findings. If successful, this mindful walking program can be scaled up as a low-cost and viable lifestyle strategy to promote healthy cognitive aging in diverse older adult populations, including those at greatest risk. TRIAL REGISTRATION: ClinicalTrials.gov number NCT06085196 (retrospectively registered on 10/08/2023).


Assuntos
Negro ou Afro-Americano , Demência , Atenção Plena , Caminhada , Humanos , Idoso , Caminhada/fisiologia , Negro ou Afro-Americano/psicologia , Demência/etnologia , Demência/prevenção & controle , Demência/psicologia , Masculino , Atenção Plena/métodos , Feminino , Cognição/fisiologia , Pessoa de Meia-Idade
3.
Orthop J Sports Med ; 12(6): 23259671241252421, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840789

RESUMO

Background: The effect of local corticosteroid (CS) injections on rotator cuff muscles remains poorly defined, despite the significance of muscle quality as a crucial prognostic factor for patients with rotator cuff tears (RCTs). Purpose: To compare alterations in gene and protein expression patterns in the rotator cuff muscles of patients with RCTs who received frequent joint CS injections with alterations in those without a history of CS injections. Study Design: Controlled laboratory study. Methods: A total of 24 rotator cuff muscle samples with medium-sized tears from 12 patients with a frequent joint CS injection history (steroid group; 7 men and 5 women who had received ≥5 injections with at least 1 within the previous 3 months; mean age, 63.0 ± 7.2 years) and 12 age- and sex-matched control patients without a history of CS injections (no-steroid group) were acquired. Alterations in the expression of genes and proteins associated with adipogenesis, myogenesis, inflammation, and muscle fibrosis were compared between the groups using quantitative reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemistry. Statistical analysis included comparison of group means using the Mann-Whitney U test, chi-square test, or Fisher exact test and logistic regression for multivariate analysis. Results: In the steroid group, the mRNA expression levels of adipogenic CCAAT/enhancer-binding protein alpha (C/EBPα; P = .008) and muscle atrophy-related genes (atrogin; P = .019) were significantly higher, and those of myogenic differentiation 1 (MyoD; P = .035), inflammatory interleukin 6 (IL-6; P = .035), and high mobility group box 1 (P = .003) were significantly lower compared with the no-steroid group. In addition, MyoD (P = .041) and IL-6 (P = .026) expression were decreased in the steroid versus no-steroid group. Immunohistochemistry revealed increased expression of C/EBPα and atrogin and decreased expression of MyoD and IL-6 in the steroid versus no-steroid group. Conclusion: Patients with RCTs and a history of frequent CS injections exhibited an upregulation of adipogenic and muscle atrophy-related genes and proteins within the rotator cuff muscles and a downregulation in the expression of myogenic and inflammatory genes and proteins in the same muscles. Clinical Relevance: These altered gene and protein expressions by frequent local CS injections may cause poor outcomes in patients with RCTs.

4.
J Int Med Res ; 52(6): 3000605241260540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38902205

RESUMO

Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition characterized by chronic activation of the immune system and a tendency to form tumorous lesions. IgG4-RD is frequently characterized by the presence of tumor-like masses affecting multiple organs and is easily mistaken for a malignant neoplasm. However, IgG4-RD affecting the appendix is extremely rare, with only seven cases reported previously. We report the case of a woman in her early 60s who presented with insidious abdominal pain and radiological findings mimicking appendiceal neoplasms. After diagnosing appendiceal neoplasms, surgery was performed. The patient had a serum IgG4 concentration of <1.35 g/L, which did not satisfy one of the three revised comprehensive diagnostic criteria for IgG4-RD. A pathological examination was conducted, and the patient was diagnosed with appendiceal IgG4-RD. To the best of our knowledge, there have been no previously reported cases of IgG4-RD affecting the appendix in patients with low serum IgG4 concentrations. This report may prove beneficial for the future understanding of IgG4-RD and for the revision of diagnostic and treatment strategies.


Assuntos
Neoplasias do Apêndice , Doença Relacionada a Imunoglobulina G4 , Imunoglobulina G , Humanos , Feminino , Neoplasias do Apêndice/diagnóstico , Neoplasias do Apêndice/patologia , Doença Relacionada a Imunoglobulina G4/diagnóstico , Diagnóstico Diferencial , Pessoa de Meia-Idade , Imunoglobulina G/sangue , Tomografia Computadorizada por Raios X , Apêndice/patologia , Apêndice/diagnóstico por imagem , Apêndice/cirurgia
5.
ACS Nano ; 18(25): 16297-16311, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38867457

RESUMO

While mesalamine, a 5-aminosalicylic acid (5-ASA), is pivotal in the management of inflammatory bowel disease (IBD) through both step-up and top-down approaches in clinical settings, its widespread utilization is limited by low bioavailability at the desired site of action due to rapid and extensive absorption in the upper gastrointestinal (GI) tract. Addressing mesalamine's pharmacokinetic challenges, here, we introduce nanoassemblies composed exclusively of a mesalamine prodrug that pairs 5-ASA with a mucoadhesive and cathepsin B-cleavable peptide. In an IBD model, orally administered nanoassemblies demonstrate enhanced accumulation and sustained retention in the GI tract due to their mucoadhesive properties and the epithelial enhanced permeability and retention (eEPR) effect. This retention enables the efficient uptake by intestinal pro-inflammatory macrophages expressing high cathepsin B, triggering a burst release of the 5-ASA. This cascade fosters the polarization toward an M2 macrophage phenotype, diminishes inflammatory responses, and simultaneously facilitates the delivery of active agents to adjacent epithelial cells. Therefore, the nanoassemblies show outstanding therapeutic efficacy in inhibiting local inflammation and contribute to suppressing systemic inflammation by restoring damaged intestinal barriers. Collectively, this study highlights the promising role of the prodrug nanoassemblies in enhancing targeted drug delivery, potentially broadening the use of mesalamine in managing IBD.


Assuntos
Doenças Inflamatórias Intestinais , Macrófagos , Mesalamina , Pró-Fármacos , Mesalamina/química , Mesalamina/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Animais , Camundongos , Humanos , Nanopartículas/química , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/administração & dosagem
6.
Biosens Bioelectron ; 260: 116436, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38824701

RESUMO

A mid-infrared label-free immunoassay-based biosensor is an effective device to help identify and quantify biomolecules. This biosensor employs a surface-enhanced infrared absorption spectroscopy, which is a highly potent sensing technique for detecting minute quantities of analytes. In this study, a biosensor was constructed using a metamaterial absorber, which facilitated strong coupling effects. For maximum coupling effect, it is necessary to enhance the near-field intensity and the spatial and spectral overlap between the optical cavity resonance and the vibrational mode of the analyte. Due to significant peak splitting, conventional baseline correction methods fail to adequately analyze such a coupling system. Therefore, we employed a coupled harmonic oscillation model to analyze the spectral distortion resulting from the peak splitting induced by the strong coupling effect. The proposed biosensor with a thrombin-binding aptamer-based immunoassay could achieve a limit of detection of 267.4 pM, paving the way for more efficient protein detection in clinical practice.


Assuntos
Técnicas Biossensoriais , Limite de Detecção , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Imunoensaio/instrumentação , Humanos , Aptâmeros de Nucleotídeos/química , Desenho de Equipamento , Espectrofotometria Infravermelho , Proteínas/análise , Trombina/análise
7.
Breast Cancer Res ; 26(1): 49, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515107

RESUMO

BACKGROUND: Patient-derived xenograft (PDX) models serve as a valuable tool for the preclinical evaluation of novel therapies. They closely replicate the genetic, phenotypic, and histopathological characteristics of primary breast tumors. Despite their promise, the rate of successful PDX engraftment is various in the literature. This study aimed to identify the key factors associated with successful PDX engraftment of primary breast cancer. METHODS: We integrated clinicopathological data with morphological attributes quantified using a trained artificial intelligence (AI) model to identify the principal factors affecting PDX engraftment. RESULTS: Multivariate logistic regression analyses demonstrated that several factors, including a high Ki-67 labeling index (Ki-67LI) (p < 0.001), younger age at diagnosis (p = 0.032), post neoadjuvant chemotherapy (NAC) (p = 0.006), higher histologic grade (p = 0.039), larger tumor size (p = 0.029), and AI-assessed higher intratumoral necrosis (p = 0.027) and intratumoral invasive carcinoma (p = 0.040) proportions, were significant factors for successful PDX engraftment (area under the curve [AUC] 0.905). In the NAC group, a higher Ki-67LI (p < 0.001), lower Miller-Payne grade (p < 0.001), and reduced proportion of intratumoral normal breast glands as assessed by AI (p = 0.06) collectively provided excellent prediction accuracy for successful PDX engraftment (AUC 0.89). CONCLUSIONS: We found that high Ki-67LI, younger age, post-NAC status, higher histologic grade, larger tumor size, and specific morphological attributes were significant factors for predicting successful PDX engraftment of primary breast cancer.


Assuntos
Neoplasias da Mama , Animais , Humanos , Feminino , Neoplasias da Mama/terapia , Neoplasias da Mama/diagnóstico , Xenoenxertos , Inteligência Artificial , Modelos Animais de Doenças , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Pathol Transl Med ; 58(2): 91-97, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38499005

RESUMO

Pancreatic neuroendocrine microtumor (PNEMT) is a neuroendocrine tumor (NET) < 0.5 cm in diameter, and it is considered benign. We report a PNEMT with high-grade transformation (HGT). A man in his 60s with von Hippel-Lindau syndrome underwent surgical resection of a NET. A second sub-centimeter nodule with a nodule-in-nodule pattern was discovered. The 0.4 cm outer nodule contained clear columnar cells with round nuclei and indistinct nucleoli, while the 0.1 cm inner nodule had eosinophilic cells with an increased nuclear to cytoplasmic ratio, vesicular nuclei, and prominent nucleoli. Tumor cells in the outer and inner nodules were synaptophysin and chromogranin positive. Only the inner nodule was p53 positive, while the outer nodule was exclusively positive for carbonic anhydrase 9 and vimentin. The Ki-67 labeling indices for the outer and inner nodules were 2.1% (grade 1) and 44.3% (grade 3), respectively. This nodule was determined to be a PNEMT with HGT. Our findings suggest that a PNEMT may not always be benign and can undergo HGT.

9.
Hip Pelvis ; 36(1): 1-11, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38420734

RESUMO

Gout is triggered by the accumulation of uric acid in the body, leading to hyperuricemia. Genetic, metabolic, and environmental factors can influence this condition. Excessive uric acid buildup results in the formation of monosodium urate (MSU) crystals, which precipitate in specific areas of the body, including the joints, where they can cause symptoms of gout. While the acute and chronic symptoms of gout have been well-documented, diagnosis of gout affecting the hip joint poses significant challenges. The global incidence of gout, the most prevalent form of inflammatory arthritis, is on the rise. Evaluation of the clinical signs, laboratory results, and imaging results is generally required for diagnosis of gout in cases where MSU crystals have not been detected. Hyperuricemia is considered a primary cause of arthritis symptoms, and comprehensive guidelines for treatment are available. Therefore, the choice of medication is straightforward, and moderate effectiveness of treatment has been demonstrated. Gout is a chronic disease, requiring lifelong uric acid-lowering medications, thus application of a treatment strategy based on the target blood uric acid concentration is necessary. Consequently, cases of gout will likely be observed more frequently by hip surgeons in clinical scenarios in the future. The objective of this review is to provide an overview of the pathophysiology of gout and subsequently examine recent advances in diagnostic methods and therapeutic agents based on an understanding of its underlying mechanisms. In addition, literature on gout-related issues affecting the hip joint, providing a useful reference for hip surgeons is examined.

10.
Curr Issues Mol Biol ; 46(2): 1485-1502, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38392214

RESUMO

Vascular dementia (VaD) is the second most common type of dementia after Alzheimer's disease. In our previous studies, we showed that wheat bran extract (WBE) reduced white matter damage in a rat VaD model and improved memory in a human clinical trial. However, starch gelatinization made the large-scale preparation of WBE difficult. To simplify the manufacturing process and increase efficacy, we attempted to find a decoction containing an optimum ratio of wheat bran, sliced citrus peel, and sliced jujube (WCJ). To find an optimal ratio, the cell survival of C6 (rat glioma) cultured under hypoxic conditions (1% O2) was measured, and apoptosis was assessed. To confirm the efficacies of the optimized WCJ for VaD, pupillary light reflex, white matter damage, and the activation of astrocytes and microglia were assessed in a rat model of bilateral common carotid artery occlusion (BCCAO) causing chronic hypoperfusion. Using a combination of both searching the literature and cell survival experiments, we chose 6:2:1 as the optimal ratio of wheat bran to sliced citrus peel to sliced jujube to prepare WCJ. We showed that phytic acid contained only in wheat bran can be used as an indicator component for the quality control of WCJ. We observed in vitro that the WCJ treatment improved cell survival by reducing apoptosis through an increase in the Bcl-2/Bax ratio. In the BCCAO experiments, the WCJ-supplemented diet prevented astrocytic and microglial activation, mitigated myelin damage in the corpus callosum and optic tract, and, consequently, improved pupillary light reflex at dosages over 100 mg/kg/day. The results suggest that the consumption of WCJ can prevent VaD by reducing white matter damage, and WCJ can be developed as a safe, herbal medicine to prevent VaD.

11.
Cell Mol Life Sci ; 81(1): 29, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38212474

RESUMO

Involution of the mammary gland after lactation is a dramatic example of coordinated cell death. Weaning causes distension of the alveolar structures due to the accumulation of milk, which, in turn, activates STAT3 and initiates a caspase-independent but lysosome-dependent cell death (LDCD) pathway. Although the importance of STAT3 and LDCD in early mammary involution is well established, it has not been entirely clear how milk stasis activates STAT3. In this report, we demonstrate that protein levels of the PMCA2 calcium pump are significantly downregulated within 2-4 h of experimental milk stasis. Reductions in PMCA2 expression correlate with an increase in cytoplasmic calcium in vivo as measured by multiphoton intravital imaging of GCaMP6f fluorescence. These events occur concomitant with the appearance of nuclear pSTAT3 expression but prior to significant activation of LDCD or its previously implicated mediators such as LIF, IL6, and TGFß3, all of which appear to be upregulated by increased intracellular calcium. We further demonstrate that increased intracellular calcium activates STAT3 by inducing degradation of its negative regulator, SOCS3. We also observed that milk stasis, loss of PMCA2 expression and increased intracellular calcium levels activate TFEB, an important regulator of lysosome biogenesis through a process involving inhibition of CDK4/6 and cell cycle progression. In summary, these data suggest that intracellular calcium serves as an important proximal biochemical signal linking milk stasis to STAT3 activation, increased lysosomal biogenesis, and lysosome-mediated cell death.


Assuntos
Cálcio , Leite , Feminino , Animais , Leite/metabolismo , Cálcio/metabolismo , Morte Celular , Lactação , Lisossomos/metabolismo , Glândulas Mamárias Animais/metabolismo , Fator de Transcrição STAT3/metabolismo
12.
Talanta ; 271: 125715, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38280264

RESUMO

Determining the activity of lysosomal ß-hexosaminidase in cells is of great importance for understanding the roles that these enzymes play in pathophysiological events. Herein, we designed the new fluorescent probe, ßGalNAc-Rhod-CM(NEt2), which consisted of a ßGalNAc-linked rhodol unit serving as a ß-hexosaminidase reactive fluorogenic moiety and a N,N'-diethylaminocoumarin (CM(NEt2)) group acting as a fluorescence marker for determining the degree of cell permeabilization. Treatment of ßGalNAc-Rhod-CM(NEt2) with ß-hexosaminidase promoted generation of Rhod-CM(NEt2), thereby leading to an increase in the intensity of fluorescence of Rhod. However, this probe did not respond to the functionally related glycosidase, O-GlcNAcase. The detection limit of ßGalNAc-Rhod-CM(NEt2) for ß-hexosaminidase was determined to be 0.52 nM, indicating that it has high sensitivity for this enzyme. Furthermore, the probe functioned as an excellent fluorogenic substrate for ß-hexosaminidase with kcat and Km values of 17 sec-1 and 22 µM, respectively. The results of cell studies using ßGalNAc-Rhod-CM(NEt2) showed that levels of ß-hexosaminidase activity in cells can be determined by measuring the intensity of fluorescence arising from Rhod and that the intensity of fluorescence of CM(NEt2) can be employed to determine the degree of cell permeabilization of the probe. Utilizing the new probe, we assessed ß-hexosaminidase activities in several types of cells and evaluated the effect of glucose concentrations in culture media on the activity of this enzyme.


Assuntos
Corantes Fluorescentes , beta-N-Acetil-Hexosaminidases , Corantes Fluorescentes/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo , Lisossomos/metabolismo , Acetilglucosaminidase/metabolismo
13.
Small Methods ; 8(3): e2301294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37988680

RESUMO

Graphitic carbon-coated ZnPS3 is prepared via direct phosphosulfurization and high energy mechanical milling (HEMM) with multiwall carbon nanotubes (MWCNTs) and first introduced as an anode for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). The HEMM process with MWCNTs reduces the particle size of as-synthesized ZnPS3 bulk to 100-500 nm and yields the ≈5 nm thick graphitic carbon coated ZnPS3 nanoparticles, which are the nanocomposites of 5 nm sized nanocrystallites embedded in the amorphous matrix. The ZnPS3 electrode undergoes the combined conversion and alloying reactions with Li and Na ions and exhibits high initial discharge and charge capacities in both LIBs and SIBs. The graphitic carbon-coated ZnPS3 electrode exhibits excellent high-rate capability and long-term cyclability. The superior electrochemical properties can be attributed to high electrical conductivity, high Li ion mobility, and high reversibility and structural stability derived from the graphitic carbon-coated nanoparticles. This study demonstrates that the novel graphitic carbon-coated ZnPS3 is a promising anode material for both LIBs and SIBs and the graphitic carbon coating methodology by HEMM is expected to apply to the various metal oxides, sulfides, and phosphides.

14.
J Neurosci ; 43(46): 7766-7779, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37734946

RESUMO

The medial nucleus of the trapezoid body (MNTB) in the auditory brainstem is the principal source of synaptic inhibition to several functionally distinct auditory nuclei. Prominent projections of individual MNTB neurons comprise the major binaural nuclei that are involved in the early processing stages of sound localization as well as the superior paraolivary nucleus (SPON), which contains monaural neurons that extract rapid changes in sound intensity to detect sound gaps and rhythmic oscillations that commonly occur in animal calls and human speech. While the processes that guide the development and refinement of MNTB axon collaterals to the binaural nuclei have become increasingly understood, little is known about the development of MNTB collaterals to the monaural SPON. In this study, we investigated the development of MNTB-SPON connections in mice of both sexes from shortly after birth to three weeks of age, which encompasses the time before and after hearing onset. Individual axon reconstructions and electrophysiological analysis of MNTB-SPON connectivity demonstrate a dramatic increase in the number of MNTB axonal boutons in the SPON before hearing onset. However, this proliferation was not accompanied by changes in the strength of MNTB-SPON connections or by changes in the structural or functional topographic precision. However, following hearing onset, the spread of single-axon boutons along the tonotopic axis increased, indicating an unexpected decrease in the tonotopic precision of the MNTB-SPON pathway. These results provide new insight into the development and organization of inhibition to SPON neurons and the regulation of developmental plasticity in diverging inhibitory pathways.SIGNIFICANCE STATEMENT The superior paraolivary nucleus (SPON) is a prominent auditory brainstem nucleus involved in the early detection of sound gaps and rhythmic oscillations. The ability of SPON neurons to fire at the offset of sound depends on strong and precise synaptic inhibition provided by glycinergic neurons in the medial nucleus of the trapezoid body (MNTB). Here, we investigated the anatomic and physiological maturation of MNTB-LSO connectivity in mice before and after the onset of hearing. We observed a period of bouton proliferation without accompanying changes in topographic precision before hearing onset. This was followed by bouton elimination and an unexpected decrease in the tonotopic precision after hearing onset. These results provide new insight into the development of inhibition to the SPON.


Assuntos
Complexo Olivar Superior , Corpo Trapezoide , Masculino , Feminino , Camundongos , Animais , Humanos , Vias Auditivas/fisiologia , Núcleo Olivar/fisiologia , Neurônios/fisiologia
15.
Nano Lett ; 23(19): 9003-9010, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37756214

RESUMO

Nonlinear optical metasurfaces offer a possibility to perform frequency mixing without the phase-matching constraints of bulk nonlinear crystals and with control of the local nonlinear response at a sub-wavelength scale. Nonlinear inter-subband polaritonic metasurfaces created by combining the semiconductor heterostructures with quantum-engineered inter-subband nonlinear response and electromagnetically engineered metal-clad nanoresonators offer by far the largest second-order nonlinear response of all condensed matter systems reported to date. However, the nonlinear optical response of these metasurfaces is limited by optical intensity saturation in the nanoresonator hot spots that prevented the achievement of power conversion efficiencies over 0.2% in three-wave mixing experiments. In this study, we propose and experimentally demonstrate dielectric inter-subband polaritonic metasurfaces for second-harmonic generation that achieve 0.37% power conversion efficiency. Our structure is created by a new design approach that combines dielectric resonators inducing Mie resonant modes with a lattice resonance to achieve a uniform and high field enhancement throughout the meta-atom volume.

16.
Knee Surg Sports Traumatol Arthrosc ; 31(11): 5238-5247, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37594502

RESUMO

PURPOSE: Joint stiffness after arthroscopic rotator cuff repair is a major concern for orthopaedic surgeons. Various antiadhesive agents are commonly administered after rotator cuff repair for its prevention. This study aimed to compare the outcomes among patients injected with different types and amounts of anti-adhesive agents after rotator cuff repair. It was hypothesized that the outcomes might differ depending on the use of the anti-adhesive agent and its type and dose. METHODS: A total of 267 patients who underwent arthroscopic rotator cuff repair with or without subacromial injection of anti-adhesive agents were enrolled. The first group (group A; 51 patients) were injected with 3 mL of poloxamer/sodium alginate-based anti-adhesive agent. The second group (group B; 93 patients) were injected with 3 mL of sodium hyaluronate-based anti-adhesive agent. The third group (group C; 82 patients) were injected with 1.5 mL of sodium hyaluronate-based anti-adhesive agent. Finally, the last group (group D; 41 patients) who did not use anti-adhesive agents served as the control. The range of motion (ROM) and pain VAS scores were measured preoperatively and at 5 weeks, 3 months, 6 months, and 1 year postoperatively. Functional outcomes were evaluated using American Shoulder and Elbow Surgeons and Constant scores, whereas cuff integrity was assessed via MRI or ultrasonography at least 6 months postoperatively. RESULTS: All ROM measurements, pain VAS scores, and functional scores were significantly improved regardless of the use, type, and dose of the anti-adhesive agents. In addition shoulder ROM and rotator cuff healing did not significantly differ among the groups (all n.s.). CONCLUSIONS: No significant differences were found in the clinical and anatomical outcomes according to the type and dose of the anti-adhesive agents subacromially injected after rotator cuff repair. LEVEL OF EVIDENCE: III.

17.
Sci Rep ; 13(1): 13150, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573439

RESUMO

Low-cost particulate matter (PM) sensors have been widely used following recent sensor-technology advancements; however, inherent limitations of low-cost monitors (LCMs), which operate based on light scattering without an air-conditioning function, still restrict their applicability. We propose a regional calibration of LCMs using a multivariate Tobit model with historical weather and air quality data to improve the accuracy of ambient air monitoring, which is highly dependent on meteorological conditions, local climate, and regional PM properties. Weather observations and PM2.5 (fine inhalable particles with diameters ≤ 2.5 µm) concentrations from two regions in Korea, Incheon and Jeju, and one in Singapore were used as training data to build a visibility-based calibration model. To validate the model, field measurements were conducted by an LCM in Jeju and Singapore, where R2 and the error after applying the model in Jeju improved (from 0.85 to 0.88) and reduced by 44% (from 8.4 to 4.7 µg m-3), respectively. The results demonstrated that regional calibration involving air temperature, relative humidity, and other local climate parameters can efficiently correct the bias of the sensor. Our findings suggest that the proposed post-processing using the Tobit model with regional weather and air quality data enhances the applicability of LCMs.

18.
Res Sq ; 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37398309

RESUMO

Involution of the mammary gland after lactation is a dramatic example of coordinated cell death. Weaning causes distension of the alveolar structures due to the accumulation of milk, which, in turn, activates STAT3 and initiates a caspase-independent but lysosome-dependent cell death (LDCD) pathway. Although the importance of STAT3 and LDCD in early mammary involution is well established, it has not been entirely clear how milk stasis activates STAT3. In this report, we demonstrate that protein levels of the PMCA2 calcium pump are significantly downregulated within 2-4 hours of experimental milk stasis. Reductions in PMCA2 expression correlate with an increase in cytoplasmic calcium in vivo as measured by multiphoton intravital imaging of GCaMP6f fluorescence. These events occur concomitant with the appearance of nuclear pSTAT3 expression but prior to significant activation of LDCD or its previously implicated mediators such as LIF, IL6 and TGFß3, all of which appear to be upregulated by increased intracellular calcium. We also observed that milk stasis, loss of PMCA2 expression and increased intracellular calcium levels activate TFEB, an important regulator of lysosome biogenesis. This is the result of increased TGFß signaling and inhibition of cell cycle progression. Finally, we demonstrate that increased intracellular calcium activates STAT3 by inducing degradation of its negative regulator, SOCS3, a process which also appears to be mediated by TGFß signaling. In summary, these data suggest that intracellular calcium serves as an important proximal biochemical signal linking milk stasis to STAT3 activation, increased lysosomal biogenesis, and lysosome-mediated cell death.

19.
Eur J Cancer ; 191: 112956, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37473465

RESUMO

BACKGROUND: The transition of human epidermal growth factor receptor 2 (HER2) status after neoadjuvant chemotherapy (NAC) in HER2-low breast cancer has not been thoroughly evaluated. Here, we evaluated the HER2 transition among HER2-zero and HER2-low breast cancer cases post-NAC and its impact on clinical outcomes. METHODS: We included 1288 patients with HER2-low or zero breast cancer who underwent NAC and surgery between 2014 and 2018 and had paired pre- and post-therapeutic HER2 status results. RESULTS: Among patients who were HER2-zero pre-NAC (n = 650), 68% and 29% were HER2-zero and HER2-low, respectively, post-NAC. Among patients who were HER2-low pre-NAC (n = 638), 32% of patients showed HER2 changes (low to zero), and 59% of patients had a constant HER2-low status post-NAC. Patients with constant HER2-low or transitions from HER2-low to zero had a higher proportion of hormone receptor positivity (84% and 79%) than those with changes from HER2-zero to low (77%) or with constant HER2-zero (56%), respectively. Multivariable logistic regression analysis revealed that patients with oestrogen receptor positivity had a higher probability of gaining HER2-low expression than those with oestrogen receptor negativity (odds ratio 2.48). No significant differences were observed in terms of overall survival or disease-free survival between patients with and without HER2-changes according to their hormone receptor status, except in the post-therapeutic HER2-low, hormone receptor-negativity subset. CONCLUSION: Temporal heterogeneity of HER2-low expression is observed in substantial numbers of post-NAC breast cancer patients. Clinical outcomes show no significant associations, except in the post-therapeutic HER2-low, hormone receptor negativity subset. The prognostic implications of HER2 transition in HER2-low breast cancer require further investigation.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Prognóstico , Receptores de Estrogênio/metabolismo , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Intervalo Livre de Doença , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante
20.
Nanoscale Horiz ; 8(10): 1366-1376, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37403772

RESUMO

Memristors are two-terminal memory devices that can change the conductance state and store analog values. Thanks to their simple structure, suitability for high-density integration, and non-volatile characteristics, memristors have been intensively studied as synapses in artificial neural network systems. Memristive synapses in neural networks have theoretically better energy efficiency compared with conventional von Neumann computing processors. However, memristor crossbar array-based neural networks usually suffer from low accuracy because of the non-ideal factors of memristors such as non-linearity and asymmetry, which prevent weights from being programmed to their targeted values. In this article, the improvement in linearity and symmetry of pulse update of a fully CMOS-compatible HfO2-based memristor is discussed, by using a second-order memristor effect with a heating pulse and a voltage divider composed of a series resistor and two diodes. We also demonstrate that the improved device characteristics enable energy-efficient and fast training of a memristor crossbar array-based neural network with high accuracy through a realistic model-based simulation. By improving the memristor device's linearity and symmetry, our results open up the possibility of a trainable memristor crossbar array-based neural network system that possesses great energy efficiency, high area efficiency, and high accuracy at the same time.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...