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1.
Clin Transl Oncol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509430

RESUMO

PURPOSE: Tri-weekly carboplatin is an established neoadjuvant treatment for triple-negative breast cancer, enhancing pathological complete response (pCR) and overall survival. This study explores if weekly carboplatin provides lower toxicity and comparable pCR rates. METHODS/PATIENTS: A retrospective multicenter study (January 2021 to March 2023) compares outcomes of weekly and tri-weekly carboplatin. RESULTS: Among 104 participants, 60% received weekly and 40% tri-weekly treatments. Weekly administration had fewer discontinuations (56.5 vs. 70.7%, p = 0.154). Both schedules exhibited similar overall toxicity (p = 0.087), with slightly higher grade 3-4 toxicity in the tri-weekly group (56.1 vs. 48.4%, p = 0.126). Hematological toxicity was comparable, but the weekly group experienced more diarrhea (p = 0.432) and asthenia (p = 0.012). Weekly treatment correlated with more frequent breast-conserving surgeries (p = 0.004). pCR rates were 50% with weekly and 61% with tri-weekly regimens (p = 0.186). CONCLUSIONS: Weekly carboplatin exhibited comparable toxicity, a trend toward fewer interruptions, and similar pCR rates. Prospective studies are essential for validating these findings.

2.
Nucl Med Commun ; 45(4): 347-351, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372041

RESUMO

The British Nuclear Medicine Society (BNMS) has developed a Research Strategy framework led by the Research Champions of the BNMS and overseen by the BNMS Research and Innovation Committee. The objectives of the Research Strategy are to improve translation of cutting-edge nuclear medicine research from bench to bedside, the implementation of state-of-the-art multimodality technologies and to enhance multicentre radionuclide research in the UK. It strives to involve patients and the public in radionuclide research and to contribute to and work with the multi-professional national and international organisations involved in research with an ultimate aim to improve nuclear medicine services, and patients' outcomes and care.


Assuntos
Medicina Nuclear , Humanos , Projetos de Pesquisa , Cintilografia , Radioisótopos
4.
Cell Rep ; 42(11): 113337, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37883232

RESUMO

Intraflagellar transport (IFT) trains, built around IFT-A and IFT-B complexes, are carried by opposing motors to import and export ciliary cargo. While transported by kinesin-2 on anterograde IFT trains, the dynein-2 motor adopts an autoinhibitory conformation until it needs to be activated at the ciliary tip to power retrograde IFT. Growing evidence has linked the IFT-A complex to retrograde IFT; however, its roles in this process remain unknown. Here, we use CRISPR-Cas9-mediated genome editing to disable the dynein-2 autoinhibition mechanism in Caenorhabditis elegans and assess its impact on IFT with high-resolution live imaging and photobleaching analyses. Remarkably, this dynein-2 "hot-wiring" approach reignites retrograde motility inside IFT-A-deficient cilia without triggering tug-of-war events. In addition to providing functional evidence that multiple mechanisms maintain dynein-2 inhibited during anterograde IFT, our data establish key roles for IFT-A in mediating motor-train coupling during IFT turnaround, promoting retrograde IFT initiation, and modulating dynein-2 retrograde motility.


Assuntos
Proteínas de Caenorhabditis elegans , Dineínas , Animais , Dineínas/metabolismo , Transporte Biológico , Cílios/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Flagelos/metabolismo
5.
Saúde debate ; 47(138): 493-503, jul.-set. 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1515570

RESUMO

RESUMO Objetivou-se estimar a prevalência da Violência Sexual (VS) contra homens brasileiros e fatores associados. Estudo transversal, que estimou a prevalência de várias formas de VS entre homens brasileiros por meio de questionário virtual. Participaram do estudo 1.241 homens de todos os estados. A maioria era jovem, entre 18 e 39 anos de idade (61,7%), heterossexual (50,2%), do Sudeste (54,4%), das classes socioeconômicas C/D/E (72,1%) e brancos (64,3%). Sobre as prevalências de VS, 70,5% afirmaram ter sofrido VS sem contato, 43,1%, VS com contato, 23,9%, VS com penetração, e 33,1%, sexo forçado. Ser bissexual, ser homossexual e ser divorciado/separado aumentaram as chances de sofrer sexo forçado. Este estudo indica que homens bissexuais e homossexuais têm mais chances de sofrer VS, corroborando outras pesquisas. Entre divorciados/separados, as chances de sofrer VS também se mostraram significativas e precisam ser mais bem exploradas. O estudo oferece a possibilidade de problematização para acolhimento de homens vítimas de VS, pensando majoritariamente na prevenção de efeitos adversos após a violência e na implantação de políticas públicas da área da saúde mais direcionadas para o público-alvo, considerando os principais fatores associados.


ABSTRACT We aimed to estimate the prevalence of sexual violence against Brazilian men and associated factors. A cross-sectional study was conducted, which estimated the prevalence of various forms of sexual violence among Brazilian men by means of a virtual questionnaire. A total of 1241 men from all Brazilian states participated in the study. Most participants were young men between 18 and 39 years (61.7%), heterosexual (50.2%), from the Southeast (54.4%), from socioeconomic classes C/D/E (72.1%), and white (64.3%). Regarding the prevalences of sexual violence, 70.5% reported non-contact sexual violence, 43.1% sexual violence with contact, 23.9% sexual violence with penetration, and 33.1% forced sex. Being bisexual homosexual, and being divorced/separated increased the odds of experiencing forced sex. This study indicates that bisexual and homosexual men are more likely to suffer sexual violence, corroborating other research. Among divorced/separated men the chances of experiencing sexual violence were also significant and need to be further explored. The study offers the possibility of problematization for the care of male victims of sexual violence, focusing mainly on the prevention of adverse effects after violence and the implementation of public policies in health that are more directed to the target audience, considering the main associated factors.

6.
Eur J Nucl Med Mol Imaging ; 50(11): 3225-3234, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37300572

RESUMO

PURPOSE: Dosimetry is rarely performed for the treatment of differentiated thyroid cancer patients with Na[131I]I (radioiodine), and information regarding absorbed doses delivered is limited. Collection of dosimetry data in a multi-centre setting requires standardised quantitative imaging and dosimetry. A multi-national, multi-centre clinical study was performed to assess absorbed doses delivered to normal organs for differentiated thyroid cancer patients treated with Na[131I]I. METHODS: Patients were enrolled in four centres and administered fixed activities of 1.1 or 3.7 GBq of Na[131I]I using rhTSH stimulation or under thyroid hormone withdrawal according to local protocols. Patients were imaged using SPECT(/CT) at variable imaging time-points following standardised acquisition and reconstruction protocols. Whole-body retention data were collected. Dosimetry for normal organs was performed at two dosimetry centres and results collated. RESULTS: One hundred and five patients were recruited. Median absorbed doses per unit administered activity of 0.44, 0.14, 0.05 and 0.16 mGy/MBq were determined for the salivary glands of patients treated at centre 1, 2, 3 and 4, respectively. Median whole-body absorbed doses for 1.1 and 3.7 GBq were 0.05 Gy and 0.16 Gy, respectively. Median whole-body absorbed doses per unit administered activity of 0.04, 0.05, 0.04 and 0.04 mGy/MBq were calculated for centre 1, 2, 3 and 4, respectively. CONCLUSIONS: A wide range of normal organ doses were observed for differentiated thyroid cancer patients treated with Na[131I]I, highlighting the necessity for individualised dosimetry. The results show that data may be collated from multiple centres if minimum standards for the acquisition and dosimetry protocols can be achieved.


Assuntos
Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo/uso terapêutico , Radiometria/métodos , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Glândulas Salivares
7.
Biomater Adv ; 150: 213437, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37116455

RESUMO

The dermal papilla (DP), a specialized compartment within the hair follicle, regulates hair growth. However, human DP cells rapidly lose their inductivity in 2D-culture given the loss of positional and microenvironmental cues. Spheroids have been capable of recreating the 3D intercellular organization of DP cells, however, DP cell-matrix interactions are poorly represented. Considering the specific nature of the DP's extracellular matrix (ECM), we functionalized gellan gum (GG) with collagen IV-(HepIII) or fibronectin-(cRGDfC) derived peptide sequences to generate a 3D environment in which the phenotype and physiological functions of DP cells are restored. We further tuned the stiffness of the microenvironments by varying GG amount. Biomimetic peptides in stiffer hydrogels promoted the adhesion of DP cells, while each peptide and amount of polymer independently influenced the type and quantity of ECM proteins deposited. Furthermore, although peptides did not seem to have an influence, stiffer hydrogels improved the inductive capacity of DP cells after short term culture. Interestingly, independently of the peptide, these hydrogels supported the recapitulation of basic hair morphogenesis-like events when incorporated in an organotypic human skin in vitro model. Our work demonstrates that tailored GG hydrogels support the generation of a microenvironment in which both cell-ECM and cell-cell interactions positively influence DP cells towards the creation of an artificial DP.


Assuntos
Derme , Hidrogéis , Humanos , Células Cultivadas , Derme/metabolismo , Hidrogéis/farmacologia , Recreação
8.
J Nucl Med ; 64(7): 1125-1130, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37116914

RESUMO

Radioactive iodine is well established as a successful treatment for differentiated thyroid cancer (DTC), although around 15% of patients have local recurrence or develop distant metastases and may become refractory to radioactive iodine (RAI). A personalized approach to treatment, based on the absorbed radiation doses delivered and using treatments to enhance RAI uptake, has not yet been developed. Methods: We performed a multicenter clinical trial to investigate the role of selumetinib, which modulates the expression of the sodium iodide symporter, and hence iodine uptake, in the treatment of RAI-refractory DTC. The iodine uptake before and after selumetinib was quantified to assess the effect of selumetinib. The range of absorbed doses delivered to metastatic disease was calculated from pre- and posttherapy imaging, and the predictive accuracy of a theranostic approach to enable personalized treatment planning was investigated. Results: Significant inter- and intrapatient variability was observed with respect to the uptake of RAI and the effect of selumetinib. The absorbed doses delivered to metastatic lesions ranged from less than 1 Gy to 1,170 Gy. A strong positive correlation was found between the absorbed doses predicted from pretherapy imaging and those measured after therapy (r = 0.93, P < 0.001). Conclusion: The variation in outcomes from RAI therapy of DTC may be explained, among other factors, by the range of absorbed doses delivered. The ability to assess the effect of treatments that modulate RAI uptake, and to estimate the absorbed doses at therapy, introduces the potential for patient stratification using a theranostic approach. Patient-specific absorbed dose planning might be the key to more successful treatment of advanced DTC.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Radioisótopos do Iodo/uso terapêutico , Radiometria , Diagnóstico por Imagem
9.
Curr Oncol ; 29(12): 9722-9732, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36547177

RESUMO

A cancer diagnosis can have a substantial impact on a patient's mental health and quality of life. The aim of this study was to investigate the prevalence of fatigue, emotional distress, and uncertainty and examine the predictive value they have on the quality of life of advanced cancer patients. A prospective, multicenter study was conducted between February 2020 and May 2021 of individuals diagnosed with an advanced, unresectable neoplasm prior to initiating systemic antineoplastic treatment. Participants completed questionnaires to quantify fatigue, emotional distress, disease uncertainty, and quality of life. A linear regression analysis was performed to study the predictive QoL variables. The study population comprised 508 patients, 53.7% of whom were male and had a mean age of 54.9 years. The most common cancers were digestive (40.6%), bronchopulmonary (29.1%), and breast (8.5%); the most frequent histology was adenocarcinoma (63%); and most were stage IV (79.7%). More than half (55.7%) suffered fatigue, and 47.7% exhibited emotional distress; both were more prevalent among women. Fatigue, emotional distress, and disease uncertainty all correlate with diminished quality of life. Similarly, ECOG performance status and the demographic variables of age, sex, and comorbidities impacted quality of life. This patient sample displayed a high prevalence of fatigue and emotional distress, together with illness uncertainty, which are clearly linked to waning quality of life. To decrease the experience of fatigue and improve mental health treatment in cancer patients, interventions based on a biopsychosocial model must be intensified.


Assuntos
Segunda Neoplasia Primária , Neoplasias , Angústia Psicológica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Incerteza , Estudos Prospectivos , Neoplasias/terapia , Fadiga/epidemiologia , Fadiga/etiologia
10.
BMC Geriatr ; 22(1): 732, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064353

RESUMO

INTRODUCTION: Most cancers occur in older individuals, who are more vulnerable due to functional impairment, multiple comorbidities, cognitive impairment, and lack of socio-familial support. These can undermine patients' sense of dignity. This study seeks to compare dignity scores in older patients with advanced cancer on sociodemographic and clinical variables and analyze the predictive value of anxiety, depression, functional limitations, and social support on dignity scores. METHODS: A prospective, multicenter, observational study conducted with participation of 15 hospitals in Spain from February 2020 to October 2021. Patients with newly-diagnosed, advanced cancer completed the dignity (PPDS), anxiety and depression (BSI), Social Support (Duke-UNC-11), and functional limitations (EORTC-C30) scales. Lineal regression analyses explored the effects of anxiety, depression, functional status, and social support on dignity, adjusting for sociodemographic and clinical variables. RESULTS: A total of 180 subjects participated in this study. The results of the correlation analysis revealed that dignity correlated negatively with anxiety, depression, and sex, and positively with social support, functional status, and longer estimated survival. Thus, women, and more anxious and depressed individuals scored lower on the dignity scale, whereas patients with more social support, fewer functional limitations, and longer estimated survival scored higher. CONCLUSION: In conclusion, being female, having a lower educational level, lower estimated survival, depression, anxiety, less social support, and limited functionality are correlated with less dignity in the elderly with advanced cancer. It is a priority to manage both physical and psychological symptoms in patients with unresectable advanced cancer to mitigate psychological distress and increase their sense of dignity.


Assuntos
Neoplasias , Respeito , Idoso , Ansiedade/psicologia , Depressão/diagnóstico , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Neoplasias/epidemiologia , Neoplasias/psicologia , Estudos Prospectivos , Qualidade de Vida/psicologia , Inquéritos e Questionários
11.
Rev Esp Patol ; 55 Suppl 1: S49-S53, 2022 09.
Artigo em Espanhol | MEDLINE | ID: mdl-36075663

RESUMO

Germ cell tumors are the most frequent neoplasia in young males. The aims of this study is to describe a case in which a postpuberal teratoma suffers a transformation to choriocarcinoma and metastasize to stomach. We have made a systematic review in PubMed and consensus documents to study this mismatch between the tumour, metastasis and the exception of gastric metastatic affectation. We describe three options to explain this discordance: a mixed germ cells tumour, a burned out tumour or a germ cells tumour derived from a malignant germ cell tumour precursor or different clonal strains. After made a thorough investigation we conclude that the most truly option is the last one as we extensive explain below. Once the gastric metastatic lesions are extremely rare and reach to <5%, but there are not conclusive assessments.


Assuntos
Coriocarcinoma , Neoplasias Embrionárias de Células Germinativas , Teratoma , Coriocarcinoma/patologia , Feminino , Humanos , Masculino , Gravidez , Estômago/patologia , Teratoma/patologia , Teratoma/secundário
12.
Br J Radiol ; 95(1138): 20200511, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35930772

RESUMO

The resulting pandemic from the novel severe acute respiratory coronavirus 2, SARS-CoV-2 (COVID-19), continues to exert a strain on worldwide health services due to the incidence of hospitalization and mortality associated with infection. The aim of clinical services throughout the period of the pandemic and likely beyond to endemic infections as the situation stabilizes is to enhance safety aspects to mitigate transmission of COVID-19 while providing a high quality of service to all patients (COVID-19 positive and negative) while still upholding excellent medical standards. In order to achieve this, new strategies of clinical service operation are essential. Researchers have published peer-reviewed reference materials such as guidelines, experiences and advice to manage the resulting issues from the unpredictable challenges presented by the pandemic. There is a range of international guidance also from professional medical organizations, including best practice and advice in order to help imaging facilities adjust their standard operating procedures and workflows in line with infection control principles. This work provides a broad review of the main sources of advice and guidelines for radiology and nuclear medicine facilities during the pandemic, and also of rapidly emerging advice and local/national experiences as facilities begin to resume previously canceled non-urgent services as well as effects on imaging research.


Assuntos
COVID-19 , Medicina Nuclear , Humanos , Controle de Infecções/métodos , Pandemias/prevenção & controle , SARS-CoV-2
13.
Cancer Invest ; 40(6): 475-482, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35468046

RESUMO

This study examines the mediating role of social support between anxious preoccupation and resilience in patients with cancer during COVID-19. NEOetic_SEOM is a prospective, multicenter study involving individuals with advanced, unresectable cancer who completed the following scales: Resilience (BCRS), Social Support (Duke-UNC-11), and anxious preoccupation subscale of the Mini-Mental Adjustment to Cancer (M-MAC) before starting antineoplastic treatment. Between March 2020 and July 2021, 507 patients (55% male; mean age, 65) were recruited. No differences in resilience were observed based on sociodemographic or clinical characteristics. Social support in people with advanced, unresectable cancer promotes both decreased anxious preoccupation and greater resilience.


Assuntos
COVID-19 , Neoplasias , Adaptação Psicológica , Idoso , Feminino , Humanos , Masculino , Pandemias , Estudos Prospectivos , Apoio Social
14.
J Vis Exp ; (180)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35253788

RESUMO

Glaucoma, the second leading cause of blindness worldwide, is a heterogeneous group of ocular disorders characterized by structural damage to the optic nerve and retinal ganglion cell (RGC) degeneration, resulting in visual dysfunction by interrupting the transmission of visual information from the eye to the brain. Elevated intraocular pressure is the most important risk factor; thus, several models of ocular hypertension have been developed in rodents by either genetic or experimental approaches to investigate the causes and effects of the disease. Among those, some limitations have been reported such as surgical invasiveness, inadequate functional assessment, requirement of extensive training, and highly variable extension of retinal damage. The present work characterizes a simple, low-cost, and efficient method to induce ocular hypertension in rodents, based on low-temperature, full-circle cauterization of the limbal vascular plexus, a major component of aqueous humor drainage. The new model provides a technically easy, noninvasive, and reproducible subacute ocular hypertension, associated with progressive RGC and optic nerve degeneration, and a unique post-operative clinical recovery rate that allows in vivo functional studies by both electrophysiological and behavioral methods.


Assuntos
Glaucoma , Hipertensão Ocular , Animais , Cauterização/efeitos adversos , Modelos Animais de Doenças , Glaucoma/etiologia , Glaucoma/cirurgia , Pressão Intraocular , Roedores
15.
Invest Ophthalmol Vis Sci ; 63(2): 5, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103748

RESUMO

Purpose: Based on our preview evidence that reduced nuclear content of the transcription factor Myc-associated protein X (MAX) is an early event associated with degeneration of retinal ganglion cells (RGCs), in the present study, our purpose was to test whether the overexpression of human MAX had a neuroprotective effect against RGC injury. Methods: Overexpression of either MAX or green fluorescent protein (GFP) in the retina was achieved by intravitreal injections of recombinant adenovirus-associated viruses (rAAVs). Lister Hooded rats were used in three models of RGC degeneration: (1) cultures of retinal explants for 30 hours ex vivo from the eyes of 14-day-old rats that had received intravitreal injections of rAAV2-MAX or the control vector rAAV2-GFP at birth; (2) an optic nerve crush model, in which 1-month-old rats received intravitreal injection of either rAAV2-MAX or rAAV2-GFP and, 4 weeks later, were operated on; and (3) an ocular hypertension (OHT) glaucoma model, in which 1-month-old rats received intravitreal injection of either rAAV2-MAX or rAAV2-GFP and, 4 weeks later, were subject to cauterization of the limbal plexus. Cell death was estimated by detection of pyknotic nuclei and TUNEL technique and correlated with MAX immunocontent in an ex vivo model of retinal explants. MAX expression was detected by quantitative RT-PCR. In the OHT model, survival of RGCs was quantified by retrograde labeling with DiI or immunostaining for BRN3a at 14 days after in vivo injury. Functional integrity of RGCs was analyzed through pattern electroretinography, and damage to the optic nerve was examined in semithin sections. Results: In all three models of RGC insult, gene therapy by overexpression of MAX prevented RGC death. Also, ON degeneration and electrophysiologic deficits were prevented in the OHT model. Conclusions: Our experiments offer proof of concept for a novel neuroprotective gene therapy for glaucomatous neurodegeneration based on overexpression of MAX.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Regulação da Expressão Gênica , Terapia Genética/métodos , Glaucoma/complicações , Regeneração Nervosa/genética , Doenças Neurodegenerativas/terapia , Neuroproteção/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/biossíntese , Morte Celular , Modelos Animais de Doenças , Feminino , Glaucoma/genética , Glaucoma/patologia , Masculino , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/genética , Ratos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia
16.
Bioeng Transl Med ; 7(1): e10235, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35079623

RESUMO

The hair follicle (HF) is an exquisite skin appendage endowed with cyclical regenerative capacity; however, de novo follicle formation does not naturally occur. Consequently, patients suffering from extensive skin damage or hair loss are deprived of the HF critical physiological and/or aesthetic functions, severally compromising skin function and the individual's psychosocial well-being. Translation of regenerative strategies has been prevented by the loss of trichogenic capacity that relevant cell populations undergo in culture and by the lack of suitable human-based in vitro testing platforms. Here, we provide a comprehensive overview of the major difficulties associated with HF regeneration and the approaches used to overcome these drawbacks. We describe key cellular requirements and discuss the importance of the HF extracellular matrix and associated signaling for HF regeneration. Finally, we summarize the strategies proposed so far to bioengineer human HF or hair-bearing skin models and disclose future trends for the field.

17.
J Cell Biol ; 221(1)2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34739033

RESUMO

The dynein-2 motor complex drives retrograde intraflagellar transport (IFT), playing a pivotal role in the assembly and functions of cilia. However, the mechanisms that regulate dynein-2 motility remain poorly understood. Here, we identify the Caenorhabditis elegans WDR60 homologue, WDR-60, and dissect the roles of this intermediate chain using genome editing and live imaging of endogenous dynein-2/IFT components. We find that loss of WDR-60 impairs dynein-2 recruitment to cilia and its incorporation onto anterograde IFT trains, reducing retrograde motor availability at the ciliary tip. Consistent with this, we show that fewer dynein-2 motors power WDR-60-deficient retrograde IFT trains, which move at reduced velocities and fail to exit cilia, accumulating on the distal side of the transition zone. Remarkably, disrupting the transition zone's NPHP module almost fully restores ciliary exit of underpowered retrograde trains in wdr-60 mutants. This work establishes WDR-60 as a major contributor to IFT, and the NPHP module as a roadblock to dynein-2 passage through the transition zone.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Cílios/metabolismo , Proteínas do Citoesqueleto/metabolismo , Dineínas/metabolismo , Flagelos/metabolismo , Animais , Proteínas de Caenorhabditis elegans/química , Proteínas do Citoesqueleto/química , Dineínas/química , Proteínas de Fluorescência Verde/metabolismo , Cinética , Mutação/genética , Domínios Proteicos , Células Receptoras Sensoriais/metabolismo
18.
J Neurochem ; 158(3): 694-709, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34081777

RESUMO

Gangliosides are glycosphingolipids abundantly expressed in the vertebrate nervous system, and are classified into a-, b-, or c-series according to the number of sialic acid residues. The enzyme GD3 synthase converts GM3 (an a-series ganglioside) into GD3, a b-series ganglioside highly expressed in the developing and adult retina. The present study evaluated the visual system of GD3 synthase knockout mice (GD3s-/- ), morphologically and functionally. The absence of b- series gangliosides in the retinas of knockout animals was confirmed by mass spectrometry imaging, which also indicated an accumulation of a-series gangliosides, such as GM3. Retinal ganglion cell (RGC) density was significantly reduced in GD3s-/- mice, with a similar reduction in the number of axons in the optic nerve. Knockout animals also showed a 15% reduction in the number of photoreceptor nuclei, but no difference in the bipolar cells. The area occupied by GFAP-positive glial cells was smaller in GD3s-/- retinas, but the number of microglial cells/macrophages did not change. In addition to the morphological alterations, a 30% reduction in light responsiveness was detected through quantification of pS6-expressing RGC, an indicator of neural activity. Furthermore, electroretinography (ERG) indicated a significant reduction in RGC and photoreceptor electrical activity in GD3s-/- mice, as indicated by scotopic ERG and pattern ERG (PERG) amplitudes. Finally, evaluation of the optomotor response demonstrated that GD3s-/- mice have reduced visual acuity and contrast sensitivity. These results suggest that b-series gangliosides play a critical role in regulating the structure and function of the mouse visual system.


Assuntos
Sensibilidades de Contraste/fisiologia , Deleção de Genes , Retina/enzimologia , Sialiltransferases/deficiência , Sialiltransferases/genética , Acuidade Visual/fisiologia , Animais , Eletrorretinografia/métodos , Feminino , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Estimulação Luminosa/métodos
19.
Cell Prolif ; 54(7): e13013, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34101928

RESUMO

BACKGROUND: Human dermal papilla (DP) cells and melanocytes (hMel) are central players in hair growth and pigmentation, respectively. In hair follicles (HFs), oxygen (O2 ) levels average 5%, being coupled with the production of reactive oxygen species (ROS), necessary to promote hair growth. MATERIALS AND METHODS: DP cell and hMel proliferation and phenotype were studied under physiological (5%O2 , physoxia) or atmospheric (21%O2 , normoxia) oxygen levels. hMel-DP cells interactions were studied in indirect co-culture or by directly co-culturing hMel with DP spheroids, to test whether their interaction affected the response to physoxia. RESULTS: Physoxia decreased DP cell senescence and improved their secretome and phenotype, as well as hMel proliferation, migration, and tyrosinase activity. In indirect co-cultures, physoxia affected DP cells' alkaline phosphatase (ALP) activity but their signalling did not influence hMel proliferation or tyrosinase activity. Additionally, ROS production was higher than in monocultures but a direct correlation between ROS generation and ALP activity in DP cells was not observed. In the 3D aggregates, where hMel are organized around the DP, both hMel tyrosinase and DP cells ALP activities, their main functional indicators, plus ROS production were higher in physoxia than normoxia. CONCLUSIONS: Overall, we showed that the response to physoxia differs according to hMel-DP cells interactions and that the microenvironment recreated when in direct contact favours their functions, which can be relevant for hair regeneration purposes.


Assuntos
Proliferação de Células/efeitos dos fármacos , Folículo Piloso/metabolismo , Melanócitos/metabolismo , Oxigênio/farmacologia , Citoesqueleto de Actina , Fosfatase Alcalina/metabolismo , Movimento Celular , Senescência Celular , Técnicas de Cocultura , Derme/citologia , Folículo Piloso/citologia , Folículo Piloso/efeitos dos fármacos , Humanos , Melanócitos/citologia , Melanócitos/efeitos dos fármacos , Monofenol Mono-Oxigenase/metabolismo , Espécies Reativas de Oxigênio/metabolismo
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