Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.456
Filtrar
1.
Laryngoscope ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115162

RESUMO

OBJECTIVE: Vocal fold scar and sulcus pose significant treatment challenges with no current optimal treatment. Platelet-rich plasma (PRP), an autologous concentration of growth factors, holds promise for regenerating the superficial lamina propria. This study aims to evaluate the potential benefits of serial PRP injections on mucosal wave restoration and vocal function. METHODS: In a prospective clinical trial across two institutions, patients with vocal fold scar underwent four serial PRP injections, one month apart. Blinded independent laryngologists and expert listeners used pretreatment and one-month post-fourth injection videostroboscopy and CAPE-V assessments to evaluate mucosal wave and voice quality changes, respectively. Additionally, patient reported outcome measures (PROMs) were evaluated. RESULTS: In the study, 15 patients received 55 PRP injections without adverse effects. Eight patients (53.3%) had mild, three patients (20%) had moderate, and four patients (26.7%) had severe scar. There was an average reduction of 8.7 points in post-treatment VHI-10 scores (p = 0.007). The raters observed an improvement in post-treatment voice in 73.4% of cases, and CAPE-V scores showed a reduction of 18.8 points on average (p = 0.036). The videostroboscopic VALI ratings showed an improvement in mucosal wave rating from 2.0 to 4.0. On average, the raters perceived the post-PRP exams to be better in 56.7% of cases. CONCLUSIONS: PRP has been validated as a safe autologous option for treatment of vocal fold scar. While results for mucosal wave and voice quality varied, there was a consistent improvement in PROMs. LEVEL OF EVIDENCE: Level 3: Prospective cohort study, with blinded analysis Laryngoscope, 2024.

2.
J Clin Med ; 13(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39124840

RESUMO

Background: Guided bone regeneration (GBR) is a reliable technique used in vertical and horizontal bone defects. The posterior mandibular region is an area limited by anatomic constraints. The use of resorbable membranes with a cortical component could compensate for the lack of rigidity of resorbable membranes without the complications of non-resorbable membranes. The aim of this study was to evaluate the mean bone gains of a xenogeneic cortical membrane in horizontal and vertical bone defects in comparison with other membranes in the literature. Methods: A porcine cortical membrane was used to perform 7 GBR in the posterior mandibular region of five patients. Preoperative (T0) and six months postoperative (T1) cone beam computed tomography were superimposed to measure the horizontal and vertical bone gain. Implants were positioned at all sites, six months after GBR. Complications and bone resorption around the implants were also documented. Results: The mean horizontal and vertical bone gains were 3.83 ± 1.41 mm and 4.17 ± 1.86 mm, respectively. The analysis of repeatability was 0.997. As many as 40% of patients experienced pain refractory to analgesics. No exposure or infectious phenomenon was observed. Conclusions: This xenogeneic cortical membrane seemed to provide interesting results in the regeneration of horizontal and vertical bone defects. Comparative and prospective studies are necessary to validate the effectiveness of this membrane.

3.
Vision Res ; 223: 108465, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39173459

RESUMO

This initial methods study presents the initial immunohistochemical and transcriptomic changes in the optic nerve head and retina from three research-consented brain-dead organ donors following prolonged and transient intraocular pressure (IOP) elevation. In this initial study, research-consented brain-dead organ donors were exposed to unilateral elevation of IOP for 7.5 h (Donor 1), 30 h (Donor 2), and 1 h (Donor 3) prior to organ procurement. Optic nerve tissue and retinal tissue was obtained following organ procurement for immunohistological and transcriptomic analysis. Optic nerve sections in Donor 1 exposed to 7.5-hours of unilateral sub-ischemic IOP elevation demonstrated higher levels of protein expression of the astrocytic marker, glial fibrillary acidic protein (GFAP), within the lamina cribrosa with greatest expression inferior temporally in the treated eye compared to control. Spatial transcriptomic analysis performed on optic nerve head tissues from Donor 2 exposed to 30 h of unilateral IOP elevation demonstrated differential transcription of mRNA across laminar and scleral regions. Immunohistochemistry of retinal sections from Donor 2 exhibited higher GFAP and IBA1 expression in the treated eye compared with control, but this was not observed in Donor 3, which was exposed to only 1-hour of IOP elevation. While there were no differences in GFAP protein expression in the retina following the 1-hour IOP elevation in Donor 3, there were higher levels of transcription of GFAP in the inner nuclear layer, and CD44 in the retinal ganglion cell layer, indicative of astrocytic and Müller glial reactivity as well as an early inflammatory response, respectively. We found that transcriptomic differences can be observed across treated and control eyes following unilateral elevation of IOP in brain dead organ donors. The continued development of this model affords the unique opportunity to define the acute mechanotranscriptomic response of the optic nerve head, evaluate the injury and repair mechanisms in the retina in response to IOP elevation, and enable correlation of in vivo imaging and functional testing with ex vivo cellular responses for the first time in the living human eye.

4.
Morphologie ; 108(363): 100902, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180804

RESUMO

BACKGROUND: In elastic and resistance arteries, an elastin-rich membrane, the Internal Elastic Lamina (IEL), separates the tunica intima from the underlying tunica media. The IEL often appears wrinkled or corrugated in histological images. These corrugations are sometimes ascribed to vessel contraction ex vivo, and to fixation artifacts, and therefore regarded as not physiologically relevant. We examine whether the IEL remains corrugated even under physiological conditions. METHODS: The diameters of carotid arteries of anesthetized pigs were measured by ultrasound. The arteries were then excised, inflated within a conical sleeve, fixed, and imaged by confocal microscopy. The conical sleeve allows fixing each artery across a wide range of diameters, which bracket its ultrasound diameter. Thus the study was designed to quantify how corrugations change with diameter for a single artery, and test whether corrugations exist when the fixed artery matches the ultrasound diameter. RESULTS: At diameters below the ultrasound diameter (i.e. when the artery was constricted as compared to ultrasound conditions), the IEL corrugations were found to decrease significantly with increasing diameter, but not fully flatten at the ultrasound diameter. The contour length of the IEL was found to be roughly 10% larger than the circumference of the artery measured by ultrasound. The physiological diameter is likely to be even smaller than the ultrasound diameter since ultrasound was conducted with the animal under general anesthesia, which leads to vasodilation, suggesting a higher level of corrugation under physiological conditions. For arterial cross sections constricted below the ultrasound diameter, the IEL contour length decreased roughly with the square root of the diameter. CONCLUSION: The primary conclusions of this study are: a) the IEL is corrugated when the artery is constricted and flattens as the artery diameter increases; b) the IEL is corrugated under physiological conditions and has a contour length at least 10% more than the physiological arterial diameter; and c) the IEL despite being relatively stiffer than the surrounding arterial layers, does not behave like an inextensible membrane.

5.
Sci Rep ; 14(1): 18644, 2024 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-39128895

RESUMO

To accurately measure the vaginal mucosa thickness across different age groups using histopathologic techniques and investigate the factors that may influence the thickness changes. This study aims to provide clinicians with objective evidence of variations in vaginal mucosal thickness, facilitating personalized medical decisions for patients. A retrospective analysis was conducted on clinical data from 348 patients who underwent local vaginal wall resection at the West China Second University Hospital, Sichuan University, from January 2021 and May 2022. The thickness of vaginal mucosa, epithelium and lamina propria was measured precisely under the microscope. And the 10th, 25th, 50th, 75th, and 90th percentile values of vaginal mucosa thickness across different age groups were counted and charted a dot-line plot. The percentile values for vaginal mucosa thickness exhibited a decreasing trend with increasing age; vaginal mucosa thickness showed significant correlations with times of delivery (P = 0.031) and age (P < 0.001), both of which were negatively associated. And vaginal mucosa thickness demonstrated no significant correlation with body mass index (BMI) (P = 0.325), times of abortions (P = 0.511), times of gestation (P = 0.101), menstrual cycle (P = 0.533), or types of delivery (P = 0.056); epithelial thickness showed significant associations with age (P < 0.001) and types of delivery (P = 0.017), both of which were negative correlations. Moreover, BMI (P = 0.429), times of abortions (P = 0.764), delivery (P = 0.079), gestation (P = 0.475), and menstrual cycle (P = 0.950) were nonassociated with epithelial thickness; lamina propria thickness displayed a significant correlation only with age (P = 0.002), and there were no obvious correlations observed between lamina propria thickness and BMI (P = 0.374), times of abortion (P = 0.417), delivery (P = 0.053), gestation (P = 0.101), types of delivery (P = 0.132) and menstrual cycle (P = 0.495). Moreover, when the age segmentation was thresholded at 35 and 50 years, both epithelial thickness and vaginal mucosa thickness were significantly correlated with age (P < 0.05). Lamina propria thickness was associated with age when the age threshold was set at 35 years (P = 0.007), whereas it showed no strong link with age when the age threshold was 50 years (P = 0.072). This study has innovatively established percentile reference values for vaginal mucosa thickness based on histopathology, furnishing clinicians with objective evidence of variations in vaginal mucosal thickness to facilitate personalized medical decisions for patients. The findings demonstrated a strong link between vaginal mucosa thickness and age, with epithelium likely playing a predominant role, while the association with lamina propria appeared to be less significant. Further research involving a larger sample size is warranted to elucidate the potential relationship with the lamina propria.


Assuntos
Mucosa , Vagina , Humanos , Feminino , Vagina/patologia , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Mucosa/patologia , Adulto Jovem , Idoso , China , Fatores Etários , Adolescente , Índice de Massa Corporal , Epitélio/patologia
6.
Int J Mol Sci ; 25(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39125769

RESUMO

A T-cell-independent (TI) pathway activated by microbiota results in the generation of low-affinity homeostatic IgA with a critical role in intestinal homeostasis. Moderate aerobic exercise (MAE) provides a beneficial impact on intestinal immunity, but the action of MAE on TI-IgA generation under senescence conditions is unknown. This study aimed to determine the effects of long-term MAE on TI-IgA production in young (3 month old) BALB/c mice exercised until adulthood (6 months) or aging (24 months). Lamina propria (LP) from the small intestine was obtained to determine B cell and plasma cell sub-populations by flow cytometry and molecular factors related to class switch recombination [Thymic Stromal Lymphopoietin (TSLP), A Proliferation-Inducing Ligand (APRIL), B Cell Activating Factor (BAFF), inducible nitric oxide synthase (iNOS), and retinal dehydrogenase (RDH)] and the synthesis of IgA [α-chain, interleukin (IL)-6, IL-21, and Growth Factor-ß (TGF-ß)]; and epithelial cells evaluated IgA transitosis [polymeric immunoglobulin receptor (pIgR), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), IL-4] by the RT-qPCR technique. The results were compared with data obtained from sedentary age-matched mice. Statistical analysis was computed with ANOVA, and p < 0.05 was considered to be a statistically significant difference. Under senescence conditions, MAE promoted the B cell and IgA+ B cells and APRIL, which may improve the intestinal response and ameliorate the inflammatory environment associated presumably with the downmodulation of pro-inflammatory mediators involved in the upmodulation of pIgR expression. Data suggested that MAE improved IgA and downmodulate the cytokine pro-inflammatory expression favoring homeostatic conditions in aging.


Assuntos
Envelhecimento , Homeostase , Imunoglobulina A , Camundongos Endogâmicos BALB C , Condicionamento Físico Animal , Animais , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia , Camundongos , Envelhecimento/imunologia , Citocinas/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Fator Ativador de Células B/metabolismo , Fator Ativador de Células B/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Masculino , Plasmócitos/imunologia , Plasmócitos/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
7.
Acta Biomater ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39173697

RESUMO

Plant leaves have to deal with various environmental influences. While the mechanical properties of petiole and lamina are generally well studied, only few studies focused on the properties of the transition zone joining petiole and lamina. Especially in peltate leaves, characterised by the attachment of the petiole to the abaxial side of the lamina, the 3D leaf architecture imposes specific mechanical stresses on the petiole and petiole-lamina transition zone. Several principles of internal anatomical organisation have been identified. Since the mechanical characterisation of the transition zone by direct measurements is difficult, we explored the mechanical properties and load-bearing mechanisms by finite-element simulations. We simulate the petiole-lamina transition zone with five different fibre models that were abstracted from CT data. For comparison, three different load cases were defined and tested in the simulation. In the proposed model, the fibres are represented in a smeared sense, where we considered transverse isotropic behavior in elements containing fibres. In a pre-processing step, we determined the fibre content, direction, and dispersion and fed them into our model. The simulations show that initially, matrix and fibres carry the load together. After relaxation of the stresses in the matrix, the fibres carry most of the load. Load dissipation and stiffness differ according to fibre arrangement and depend, among other things, on orientation and cross-linking of the fibres and fibre amount. Even though the presented method is a simplified approach, it is able to show the different load-bearing capacities of the presented fibre arrangements. STATEMENT OF SIGNIFICANCE: In plant leaves, the petiole-lamina transition zone is an important structural element facilitating water and nutrient transport, as well as load dissipation from the lamina into the petiole. Especially in peltate leaves, the 3D leaf architecture imposes specific mechanical stresses on the petiole-lamina transition zone. This study aims at investigating its mechanical behavior using finite-element simulations. The proposed continuum mechanical anisotropic viscoelastic material model is able to simulate the transition zone under different loads while also considering different fibre arrangements. The simulations highlight the load-bearing mechanisms of different fibre organisations, show the mechanical significance of the petiole-lamina transition zone and can be used in the design of a future biomimetic junction in construction.

8.
Int J Mol Sci ; 25(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39201542

RESUMO

Human primary lens epithelial cultures serve as an in vitro model for posterior capsular opacification (PCO) formation. PCO occurs when residual lens epithelial cells (LECs) migrate and proliferate after cataract surgery, differentiating into fibroblastic and lens fiber-like cells. This study aims to show and compare the bio-macromolecular profiles of primary LEC cultures and postoperative lens epithelia LECs on basal laminas (bls), while also analyzing bls and cultured LECs separately. Using synchrotron radiation-based Fourier transform infrared (SR-FTIR) (Bruker, Karlsruhe, Germany) microspectroscopy at the Spanish synchrotron light source ALBA, we observed that the SR-FTIR measurements were predominantly influenced by the strong collagen absorbance of the bls. Cultured LECs on bls showed a higher collagen contribution, indicated by higher vas CH3, CH2 and CH3 wagging and deformation, and the C-N stretching of collagen. In contrast, postoperative LECs on bls showed a higher cell contribution, indicated by the vsym CH2 peak and the ratio between vas CH2 and vas CH3 peaks. The primary difference revealed using SR-FTIR is the greater LEC contribution in spectra recorded from postoperative lens epithelia compared to cultured LECs on bls. IR spectra for bl, cultured LECs and postoperative lens epithelia could be valuable for future research.


Assuntos
Células Epiteliais , Cristalino , Síncrotrons , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Cultivadas , Cristalino/metabolismo , Cristalino/citologia , Opacificação da Cápsula/metabolismo , Opacificação da Cápsula/patologia , Membrana Basal/metabolismo , Colágeno/metabolismo , Idoso , Pessoa de Meia-Idade
9.
Int J Mol Sci ; 25(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39201561

RESUMO

Glaucoma, a leading cause of blindness, is a multifactorial condition that leads to progressive loss of retinal ganglion cells (RGCs) and vision. Therapeutic interventions based on reducing ocular hypertension are not always successful. Emerging features of glaucoma include mitochondrial dysfunction and oxidative stress. In the current study, NDI1-based gene therapy, which improves mitochondrial function and reduces reactive oxygen species, was delivered intraocularly via an adeno-associated viral vector (AAV). This AAV-NDI1 therapy protected RGCs from cell death in treated (1552.4 ± 994.0 RGCs/mm2) versus control eyes (1184.4 ± 978.4 RGCs/mm2, p < 0.05) in aged DBA/2J mice, a murine model of glaucoma. The photonegative responses (PhNRs) of RGCs were also improved in treated (6.4 ± 3.3 µV) versus control eyes (5.0 ± 3.1 µV, p < 0.05) in these mice. AAV-NDI1 also provided benefits in glaucomatous human lamina cribrosa (LC) cells by significantly increasing basal and maximal oxygen consumption rates and ATP production in these cells. Similarly, NDI1 therapy significantly protected H2O2-insulted primary porcine LC cells from oxidative stress. This study highlights the potential utility of NDI1 therapies and the benefits of improving mitochondrial function in the treatment of glaucoma.


Assuntos
Dependovirus , Modelos Animais de Doenças , Terapia Genética , Vetores Genéticos , Glaucoma , Estresse Oxidativo , Células Ganglionares da Retina , Animais , Dependovirus/genética , Glaucoma/terapia , Glaucoma/metabolismo , Glaucoma/patologia , Camundongos , Terapia Genética/métodos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Humanos , Vetores Genéticos/genética , Mitocôndrias/metabolismo , Camundongos Endogâmicos DBA , Espécies Reativas de Oxigênio/metabolismo , Suínos
10.
Bio Protoc ; 14(14): e5035, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39100598

RESUMO

Despite playing diverse physiological roles, the area surrounding the central canal, lamina X, remains one of the least studied spinal cord regions. Technical challenges and limitations of the commonly used experimental approaches are the main difficulties that hamper lamina X research. In the current protocol, we describe a reliable method for functional investigation of lamina X neurons that requires neither time-consuming slicing nor sophisticated in vivo experiments. Our approach relies on ex vivo hemisected spinal cord preparation that preserves the rostrocaudal and mediolateral spinal architecture as well as the dorsal roots, and infrared LED oblique illumination for visually guided patch clamp in thick blocks of tissue. When coupled with electric stimulation of the spared dorsal roots, electrophysiological recordings provide information on primary afferent inputs to lamina X neurons from myelinated and non-myelinated fibers and allow estimating primary afferent-driven presynaptic inhibition. Overall, we describe a simple, time-efficient, inexpensive, and versatile approach for lamina X research. Key features • Quick and easy preparation procedure that grants access to lamina X neurons without spinal cord slicing • Preserved rostrocaudal and mediolateral connectivity and preserved primary afferent supply • Ability to perform electrophysiological recordings in combination with dorsal root stimulations allowing to study afferent inputs and presynaptic inhibition of lamina X neurons.

11.
Development ; 151(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39087588

RESUMO

The Spalt transcriptional regulators participate in a variety of cell fate specification processes during development, regulating transcription through interactions with DNA AT-rich regions. Spalt proteins also bind to heterochromatic regions, and some of their effects require interactions with the NuRD chromatin remodeling and deacetylase complex. Most of the biological roles of Spalt proteins have been characterized in diploid cells engaged in cell proliferation. Here, we address the function of Drosophila Spalt genes in the development of a larval tissue formed by polyploid cells, the prothoracic gland, the cells of which undergo several rounds of DNA replication without mitosis during larval development. We show that prothoracic glands depleted of Spalt expression display severe changes in the size of the nucleolus, the morphology of the nuclear envelope and the disposition of the chromatin within the nucleus, leading to a failure in the synthesis of ecdysone. We propose that loss of ecdysone production in the prothoracic gland of Spalt mutants is primarily caused by defects in nuclear pore complex function that occur as a consequence of faulty interactions between heterochromatic regions and the nuclear envelope.


Assuntos
Proteínas de Drosophila , Ecdisona , Fatores de Transcrição , Animais , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Ecdisona/metabolismo , Larva/metabolismo , Larva/crescimento & desenvolvimento , Larva/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Membrana Nuclear/metabolismo , Membrana Nuclear/genética , Drosophila/metabolismo , Drosophila/genética , Cromatina/metabolismo , Nucléolo Celular/metabolismo , Poro Nuclear/metabolismo , Poro Nuclear/genética , Mutação/genética , Proteínas Repressoras
12.
Int Immunol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38955508

RESUMO

Regulatory T cells (Tregs) ameliorate inflammatory bowel diseases. However, their plasticity is not completely understood. In this study using a mouse colitis model, Tregs and T helper 17 (Th17)-like Tregs were detected and sorted using flow cytometry, followed by transcriptome sequencing, real-time RT-PCR, and flow cytometry to analyze the mRNA profiles of these cells. Treg plasticity was evaluated by in vitro differentiation assays. The immunosuppressive activities of Tregs and Th17-like Tregs were assessed in an adoptive transfer assay. We found Tregs-derived Th17-like Tregs in inflamed colonic lamina propria (LP). LP Th17-like Tregs expressed higher Th17-related cytokines and lower immunosuppressive cytokines compared with LP Tregs. Notably, Tregs expressed higher Yes-associated protein 1 (YAP1) but lower transcriptional coactivator with PDZ­binding motif (TAZ) than Th17-like Tregs. Verteporfin-mediated inhibition of YAP1 activity enhanced Th17-like Treg generation, whereas IBS008739-induced TAZ activation did not affect Th17-like Treg generation. Besides, verteporfin enhanced while IBS008739 suppressed the differentiation of Th17-like Tregs into Th17 cells. Furthermore, YAP1 activated STAT5 signaling in Tregs, whereas YAP1 and TAZ activated STAT3 and STAT5 signaling in Th17-like Tregs. Compared with Tregs, Th17-like Tregs were less efficacious in ameliorating colitis. Therefore, YAP1 suppressed Treg differentiation into Th17-like Tregs. Both YAP1 and TAZ inhibited the differentiation of Th17-like Tregs into Th17 cells. Therefore, YAP1 and TAZ probably maintain the immunosuppressive activities of Tregs and Th17-like Tregs in colitis.

13.
Artigo em Inglês | MEDLINE | ID: mdl-39036566

RESUMO

IgG4-related disease (IgG4-RD) is a fibro-inflammatory condition that can affect various organs. Localized sinonasal IgG4-RD is a rare condition characterized by bone and soft-tissue invasion. In this report, we present a case of a patient initially diagnosed with chronic rhinosinusitis, who underwent endoscopic sinus surgery and was later found to have biopsy proven IgG4-related sinonasal disease despite having normal serum levels of IgG4, resulting in erosion of the right lamina papyracea.

14.
Exp Eye Res ; 246: 110010, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39069000

RESUMO

This study aimed to develop and evaluate a guinea pig model for glaucoma, comparing resultant eyeball enlargement with an existing myopia model. Thirty guinea pigs underwent intracameral injection of magnetic microspheres to induce chronic ocular hypertension (COH). Intraocular pressure (IOP) was systematically monitored, revealing a successful induction of COH in 73.33% of the guinea pigs. The mean IOP increased from a baseline of 18.04 ± 1.33 mmHg, reaching a peak at week 3 (36.31 ± 6.13 mmHg) and remaining elevated for at least 7 weeks. All data are presented as mean ± standard deviation of the mean. Subsequently, detailed assessments were conducted to validate the established glaucoma model. Immunofluorescent staining demonstrated a significant decrease in the density of retinal ganglion cells (RGC) in the glaucoma group. Optic disc excavation and notable thinning of the lamina cribrosa (LC) were observed. The quantity of optic nerve ax·ons in glaucoma group gradually decreased from baseline (44553 ± 3608/mm2) to week 4 (28687 ± 2071/mm2) and week 8 (17977 ± 3697/mm2). Moreover, regarding the global enlargement of eyeballs, both the transverse and longitudinal axis in glaucomatous eyes were found to be significantly larger than that in myopic eyes, particularly in the anterior chamber depth (1.758 ± 0.113 mm vs. 1.151 ± 0.046 mm). These findings indicate distinct patterns of structural changes associated with glaucoma and myopia in the guinea pig model. This guinea pig model holds promise for future research aimed at exploring biomechanical mechanisms, therapeutic interventions, and advancing our understanding of the relationship between glaucoma and myopia.


Assuntos
Modelos Animais de Doenças , Glaucoma , Pressão Intraocular , Miopia , Células Ganglionares da Retina , Animais , Cobaias , Miopia/fisiopatologia , Miopia/patologia , Pressão Intraocular/fisiologia , Células Ganglionares da Retina/patologia , Glaucoma/fisiopatologia , Glaucoma/patologia , Disco Óptico/patologia , Masculino , Tomografia de Coerência Óptica , Tonometria Ocular
15.
Artigo em Inglês | MEDLINE | ID: mdl-39074661

RESUMO

The coincidence in a patient of Hemifacial Spasm and Trigeminal Neuralgia is not frequent. A case is presented with the objective of showing this association due to the abnormal activation of the Trigemino-Facial Reflex. A 55-year-old woman with an 8-year history of left-sided hemifacial spasm and typical trigeminal pain in the ipsilateral V1 and V2 territory. The physical examination shows spasms in the left hemiface, with reproduction of intense pain upon sensory stimulation of the skin on the forehead and upper dental arch. The MRI showed a vessel in intimate contact with the entrance area of ​​the left trigeminal nerve. A left retrosigmoid approach was performed. First, the entrance area of ​​the trigeminal nerve was accessed, finding a clear vascular conflict, which was isolated with Teflon. Then, the trajectory was changed and the exit zone of the facial nerve was accessed, and no type of vascular conflict was identified. The patient presented complete resolution of the Hemifacial Spasm and the associated trigeminal pain. The analysis of this case allows us to conclude that during microvascular decompression of the Facial Nerve, if frank proximal compression is not evident, the Trigeminofacial structural relationship must be taken into account, making it necessary to explore the Trigeminal Nerve.

16.
Curr Biol ; 34(14): 3133-3151.e10, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38964319

RESUMO

The sense of touch is conferred by the conjoint function of somatosensory neurons and skin cells. These cells meet across a gap filled by a basal lamina, an ancient structure found in metazoans. Using Caenorhabditis elegans, we investigate the composition and ultrastructure of the extracellular matrix at the epidermis and touch receptor neuron (TRN) interface. We show that membrane-matrix complexes containing laminin, nidogen, and the MEC-4 mechano-electrical transduction channel reside at this interface and are central to proper touch sensation. Interestingly, the dimensions and spacing of these complexes correspond with the discontinuous beam-like extracellular matrix structures observed in serial-section transmission electron micrographs. These complexes fail to coalesce in touch-insensitive extracellular matrix mutants and in dissociated neurons. Loss of nidogen reduces the density of mechanoreceptor complexes and the amplitude of the touch-evoked currents they carry. Thus, neuron-epithelium cell interfaces are instrumental in mechanosensory complex assembly and function. Unlike the basal lamina ensheathing the pharynx and body wall muscle, nidogen recruitment to the puncta along TRNs is not dependent upon laminin binding. MEC-4, but not laminin or nidogen, is destabilized by point mutations in the C-terminal Kunitz domain of the extracellular matrix component, MEC-1. These findings imply that somatosensory neurons secrete proteins that actively repurpose the basal lamina to generate special-purpose mechanosensory complexes responsible for vibrotactile sensing.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Mecanorreceptores , Mecanotransdução Celular , Animais , Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Mecanorreceptores/metabolismo , Mecanorreceptores/fisiologia , Mecanotransdução Celular/fisiologia , Tato/fisiologia , Membrana Basal/metabolismo , Membrana Basal/fisiologia , Matriz Extracelular/metabolismo , Laminina/metabolismo , Glicoproteínas de Membrana , Proteínas de Membrana
17.
Cureus ; 16(7): e65392, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39071068

RESUMO

This article is a discussion of two cases of young adults with lesions in similar locations in the anterior maxilla, i.e., the canine-to-canine region, similar history, and comparable radiology. Both cases were histologically diagnosed as calcifying odontogenic cysts. Case 1 was a male aged 28 years with diffuse, firm left malar area facial swelling with pain in associated teeth for a month. Intraorally, he had a gingivo-vestibular swelling also extending palatally in the anterior left maxillary region extending from the distal surface of the left maxillary central incisor to the mesial surface of the left maxillary canine. The overlying mucosa was normal in appearance. The radiograph showed a large unilocular radiolucency in the affected region. The lesion was excised followed by curettage and primary closure. Case 2 was a female aged 25 years with a lumpy mass and pain in associated teeth since one year in the left canine-premolar region with an external swelling in the left ala of the nose region that extended superiorly to the zygomatic arch. The color of the skin as well as the intraoral mucosa was normal, and an orthopantomogram (OPG)revealed a unilocular radiolucency in the left maxillary canine-premolar region with resorption of premolar roots. Treatment included surgical enucleation and bone curettage. Both cases have been in follow-up for about a year and have shown non-incidental healing.

18.
Biotechnol Bioeng ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020522

RESUMO

In recent years, nuclear mechanobiology gained a lot of attention for the study of cell responses to external cues like adhesive forces, applied compression, and/or shear-stresses. In details, the Lamin-A protein-as major constituent of the cell nucleus structure-plays a crucial role in the overall nucleus mechanobiological response. However, modeling and analysis of Lamin-A protein organization upon rapid compression conditions in microfluidics are still difficult to be performed. Here, we introduce the possibility to control an applied microfluidic compression on single cells, deforming them up to the nucleus level. In a wide range of stresses (~1-102 kPa) applied on healthy and cancer cells, we report increasing Lamin-A intensities which scale as a power law with the applied compression. Then, an increase up to two times of the nuclear viscosity is measured in healthy cells, due to the modified Lamin-A organization. This is ascribable to the increasing assembly of Lamin-A filament-like branches which increment both in number and elongation (up to branches four-time longer). Moreover, the solution of a computational model of differential equations is presented as a powerful tool for a single cell prediction of the Lamin-A assembly as a function of the applied compression.

19.
bioRxiv ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39005395

RESUMO

Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare genetic condition characterized by features of accelerated aging, and individuals with HGPS seldom live beyond their mid-teens. The syndrome is commonly caused by a point mutation in the LMNA gene which codes for lamin A and its splice variant lamin C, components of the nuclear lamina. The mutation causing HGPS leads to production of a truncated, farnesylated form of lamin A referred to as "progerin." Progerin is also expressed at low levels in healthy individuals and appears to play a role in normal aging. HGPS is associated with an accumulation of genomic DNA double-strand breaks (DSBs) and alterations in the nature of DSB repair. The source of DSBs in HGPS is often attributed to stalling and subsequent collapse of replication forks in conjunction with faulty recruitment of repair factors to damage sites. In this work, we used a model system involving immortalized human cell lines to investigate progerin-induced genomic damage. Using an immunofluorescence approach to visualize phosphorylated histone H2AX foci which mark sites of genomic damage, we report that cells engineered to express progerin displayed a significant elevation of endogenous damage in the absence of any change in the cell cycle profile or doubling time of cells. Genomic damage was enhanced and persistent in progerin-expressing cells treated with hydroxyurea. Overexpression of wild-type lamin A did not elicit the outcomes associated with progerin expression. Our results show that DNA damage caused by progerin can occur independently from global changes in replication or cell proliferation.

20.
Comput Struct Biotechnol J ; 23: 2240-2250, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38827231

RESUMO

The 3D conformations of chromosomes can encode biological significance, and the implications of such structures have been increasingly appreciated recently. Certain chromosome structural features, such as A/B compartmentalization, are frequently extracted from Hi-C pairwise genome contact information (physical association between different regions of the genome) and compared with linear annotations of the genome, such as histone modifications and lamina association. We investigate how additional properties of chromosome structure can be deduced using an abstract graph representation of the contact heatmap, and describe specific network properties that can have a strong connection with some of these biological annotations. We constructed chromosome structure networks (CSNs) from bulk Hi-C data and calculated a set of site-resolved (node-based) network properties. These properties are useful for characterizing certain aspects of chromosomal structure. We examined the ability of network properties to differentiate several scenarios, such as haploid vs diploid cells, partially inverted nuclei vs conventional architecture, depletion of chromosome architectural proteins, and structural changes during cell development. We also examined the connection between network properties and a series of other linear annotations, such as histone modifications and chromatin states including poised promoter and enhancer labels. We found that semi-local network properties exhibit greater capability in characterizing genome annotations compared to diffusive or ultra-local node features. For example, the local square clustering coefficient can be a strong classifier of lamina-associated domains. We demonstrated that network properties can be useful for highlighting large-scale chromosome structure differences that emerge in different biological situations.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA