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1.
PLoS One ; 19(5): e0297462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38768117

RESUMO

Considering the advantages of q-rung orthopair fuzzy 2-tuple linguistic set (q-RFLS), which includes both linguistic and numeric data to describe evaluations, this article aims to design a new decision-making methodology by integrating Vlsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) and qualitative flexible (QUALIFLEX) methods based on the revised aggregation operators to solve multiple criteria group decision making (MCGDM). To accomplish this, we first revise the extant operational laws of q-RFLSs to make up for their shortcomings. Based on novel operational laws, we develop q-rung orthopair fuzzy 2-tuple linguistic (q-RFL) weighted averaging and geometric operators and provide the corresponding results. Next, we develop a maximization deviation model to determine the criterion weights in the decision-making procedure, which accounts for partial weight unknown information. Then, the VIKOR and QUALIFLEX methodologies are combined, which can assess the concordance index of each ranking combination using group utility and individual maximum regret value of alternative and acquire the ranking result based on each permutation's general concordance index values. Consequently, a case study is conducted to select the best bike-sharing recycling supplier utilizing the suggested VIKOR-QUALIFLEX MCGDM method, demonstrating the method's applicability and availability. Finally, through sensitivity and comparative analysis, the validity and superiority of the proposed method are demonstrated.


Assuntos
Tomada de Decisões , Lógica Fuzzy , Linguística , Humanos , Algoritmos
2.
Sci Rep ; 14(1): 10659, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724560

RESUMO

Due to the fuzziness of the medical field, q-rung orthopair fuzzy 2-tuple linguistic (q-RF2L) set is the privileged way to aid medical professionals in conveying their assessments in the patient prioritization problem. The theme of the present study is to put forward a novel approach centered around the merging of prioritized averaging (PA) and the Maclaurin symmetric mean (MSM) operator within q-RF2L context. According to the prioritization of the professionals and the correlation among the defined criteria, we apply both PA and MSM to assess priority degrees and relationships, respectively. Keeping the pluses of the PA and MSM operators in mind, we introduce two aggregation operators (AOs), namely q-RF2L prioritized Maclaurin symmetric mean and q-RF2L prioritized dual Maclaurin symmetric mean operators. Meanwhile, some essential features and remarks of the proposed AOs are discussed at length. Based on the formulated AOs, we extend the weighted aggregated sum product assessment methodology to cope with q-RF2L decision-making problems. Ultimately, to illustrate the practicality and effectiveness of the stated methodology, a real-world example of patients' prioritization problem is addressed, and an in-depth analysis with prevailing methods is performed.

3.
Front Cell Neurosci ; 18: 1353895, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419657

RESUMO

The back-propagation of an action potential (AP) from the axon/soma to the dendrites plays a central role in dendritic integration. This process involves an intricate orchestration of various ion channels, but a comprehensive understanding of the contribution of each channel type remains elusive. In this study, we leverage ultrafast membrane potential recordings (Vm) and Ca2+ imaging techniques to shed light on the involvement of N-type voltage-gated Ca2+ channels (VGCCs) in layer-5 neocortical pyramidal neurons' apical dendrites. We found a selective interaction between N-type VGCCs and large-conductance Ca2+-activated K+ channels (BK CAKCs). Remarkably, we observe that BK CAKCs are activated within a mere 500 µs after the AP peak, preceding the peak of the Ca2+ current triggered by the AP. Consequently, when N-type VGCCs are inhibited, the early broadening of the AP shape amplifies the activity of other VGCCs, leading to an augmented total Ca2+ influx. A NEURON model, constructed to replicate and support these experimental results, reveals the critical coupling between N-type and BK channels. This study not only redefines the conventional role of N-type VGCCs as primarily involved in presynaptic neurotransmitter release but also establishes their distinct and essential function as activators of BK CAKCs in neuronal dendrites. Furthermore, our results provide original functional validation of a physical interaction between Ca2+ and K+ channels, elucidated through ultrafast kinetic reconstruction. This insight enhances our understanding of the intricate mechanisms governing neuronal signaling and may have far-reaching implications in the field.

4.
Sci Rep ; 14(1): 4967, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424206

RESUMO

The toxin AaH-II, from the scorpion Androctonus australis Hector venom, is a 64 amino acid peptide that targets voltage-gated Na+ channels (VGNCs) and slows their inactivation. While at macroscopic cellular level AaH-II prolongs the action potential (AP), a functional analysis of the effect of the toxin in the axon initial segment (AIS), where VGNCs are highly expressed, was never performed so far. Here, we report an original analysis of the effect of AaH-II on the AP generation in the AIS of neocortical layer-5 pyramidal neurons from mouse brain slices. After determining that AaH-II does not discriminate between Nav1.2 and Nav1.6, i.e. between the two VGNC isoforms expressed in this neuron, we established that 7 nM was the smallest toxin concentration producing a minimal detectable deformation of the somatic AP after local delivery of the toxin. Using membrane potential imaging, we found that, at this minimal concentration, AaH-II substantially widened the AP in the AIS. Using ultrafast Na+ imaging, we found that local application of 7 nM AaH-II caused a large increase in the slower component of the Na+ influx in the AIS. Finally, using ultrafast Ca2+ imaging, we observed that 7 nM AaH-II produces a spurious slow Ca2+ influx via Ca2+-permeable VGNCs. Molecules targeting VGNCs, including peptides, are proposed as potential therapeutic tools. Thus, the present analysis in the AIS can be considered a general proof-of-principle on how high-resolution imaging techniques can disclose drug effects that cannot be observed when tested at the macroscopic level.


Assuntos
Animais Peçonhentos , Segmento Inicial do Axônio , Venenos de Escorpião , Camundongos , Animais , Potenciais de Ação , Escorpiões , Peptídeos , Venenos de Escorpião/farmacologia , Venenos de Escorpião/química
5.
World J Urol ; 41(12): 3527-3533, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37845554

RESUMO

PURPOSE: To assess a region-of-interest-based computer-assisted diagnosis system (CAD) in characterizing aggressive prostate cancer on magnetic resonance imaging (MRI) from patients under active surveillance (AS). METHODS: A prospective biopsy database was retrospectively searched for patients under AS who underwent MRI and subsequent biopsy at our institution. MRI lesions targeted at baseline biopsy were retrospectively delineated to calculate the CAD score that was compared to the Prostate Imaging-Reporting and Data System (PI-RADS) version 2 score assigned at baseline biopsy. RESULTS: 186 patients were selected. At baseline biopsy, 51 and 15 patients had International Society of Urological Pathology (ISUP) grade ≥ 2 and ≥ 3 cancer respectively. The CAD score had significantly higher specificity for ISUP ≥ 2 cancers (60% [95% confidence interval (CI): 51-68]) than the PI-RADS score (≥ 3 dichotomization: 24% [CI: 17-33], p = 0.0003; ≥ 4 dichotomization: 32% [CI: 24-40], p = 0.0003). It had significantly lower sensitivity than the PI-RADS ≥ 3 dichotomization (85% [CI: 74-92] versus 98% [CI: 91-100], p = 0.015) but not than the PI-RADS ≥ 4 dichotomization (94% [CI:85-98], p = 0.104). Combining CAD findings and PSA density could have avoided 47/184 (26%) baseline biopsies, while missing 3/51 (6%) ISUP 2 and no ISUP ≥ 3 cancers. Patients with baseline negative CAD findings and PSAd < 0.15 ng/mL2 who stayed on AS after baseline biopsy had a 9% (4/44) risk of being diagnosed with ISUP ≥ 2 cancer during a median follow-up of 41 months, as opposed to 24% (18/74) for the others. CONCLUSION: The CAD could help define AS patients with low risk of aggressive cancer at baseline assessment and during subsequent follow-up.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Estudos Prospectivos , Conduta Expectante , Diagnóstico por Computador , Computadores , Biópsia Guiada por Imagem/métodos , Antígeno Prostático Específico
7.
Sci Rep ; 13(1): 2789, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797313

RESUMO

q-ROPFLS, including numeric and linguistic data, has a wide range of applications in handling uncertain information. This article aims to investigate q-ROPFL correlation coefficient based on the proposed information energy and covariance formulas. Moreover, considering that different q-ROPFL elements may have varying criteria weights, the weighted correlation coefficient is further explored. Some desirable characteristics of the presented correlation coefficients are also discussed and proven. In addition, some theoretical development is provided, including the concept of composition matrix, correlation matrix, and equivalent correlation matrix via the proposed correlation coefficients. Then, a clustering algorithm is expanded where data is expressed in q-ROPFL form with unknown weight information and is explained through an illustrative example. Besides, detailed parameter analysis and comparative study are performed with the existing approaches to reveal the effectiveness of the framed algorithm.

8.
J Vis Exp ; (184)2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35815968

RESUMO

Measurements of retinal neuronal light responses are critical to investigating the physiology of the healthy retina, determining pathological changes in retinal diseases, and testing therapeutic interventions. The ex vivo electroretinogram (ERG) allows the quantification of contributions from individual cell types in the isolated retina by addition of specific pharmacological agents and evaluation of tissue-intrinsic changes independently of systemic influences. Retinal light responses can be measured using a specialized ex vivo ERG specimen holder and recording setup, modified from existing patch clamp or microelectrode array equipment. Particularly, the study of ON-bipolar cells, but also of photoreceptors, has been hampered by the slow but progressive decline of light responses in the ex vivo ERG over time. Increased perfusion speed and adjustment of the perfusate temperature improve ex vivo retinal function and maximize response amplitude and stability. The ex vivo ERG uniquely allows the study of individual retinal neuronal cell types. In addition, improvements to maximize response amplitudes and stability allow the investigation of light responses in retina samples from large animals, as well as human donor eyes, making the ex vivo ERG a valuable addition to the repertoire of techniques used to investigate retinal function.


Assuntos
Eletrorretinografia , Doenças Retinianas , Animais , Eletrorretinografia/métodos , Humanos , Microeletrodos , Retina/fisiologia
9.
Nature ; 606(7913): 351-357, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35545677

RESUMO

Death is defined as the irreversible cessation of circulatory, respiratory or brain activity. Many peripheral human organs can be transplanted from deceased donors using protocols to optimize viability. However, tissues from the central nervous system rapidly lose viability after circulation ceases1,2, impeding their potential for transplantation. The time course and mechanisms causing neuronal death and the potential for revival remain poorly defined. Here, using the retina as a model of the central nervous system, we systemically examine the kinetics of death and neuronal revival. We demonstrate the swift decline of neuronal signalling and identify conditions for reviving synchronous in vivo-like trans-synaptic transmission in postmortem mouse and human retina. We measure light-evoked responses in human macular photoreceptors in eyes removed up to 5 h after death and identify modifiable factors that drive reversible and irreversible loss of light signalling after death. Finally, we quantify the rate-limiting deactivation reaction of phototransduction, a model G protein signalling cascade, in peripheral and macular human and macaque retina. Our approach will have broad applications and impact by enabling transformative studies in the human central nervous system, raising questions about the irreversibility of neuronal cell death, and providing new avenues for visual rehabilitation.


Assuntos
Transdução de Sinal Luminoso , Reabilitação Neurológica , Mudanças Depois da Morte , Retina , Animais , Autopsia , Morte Celular/efeitos da radiação , Sistema Nervoso Central/efeitos da radiação , Humanos , Transdução de Sinal Luminoso/efeitos da radiação , Macaca , Camundongos , Retina/metabolismo , Retina/efeitos da radiação , Fatores de Tempo
10.
BMC Public Health ; 22(1): 893, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513805

RESUMO

BACKGROUND: Public acceptance of governmental measures are key to controlling the spread of infectious diseases. The COVID-19 pandemic has placed a significant burden on healthcare systems for high-income countries as well as low- and middle-income countries (LMICs). The ability of LMICs to respond to the challenge of the COVID-19 pandemic has been limited and may have affected the impact of governmental strategies to control the spread of COVID-19. This study aimed to evaluate and compare public opinion on the governmental COVID-19 response of high and LMICs in the Middle East and benchmark it to international countries. METHODS: An online, self-administered questionnaire was distributed among different Middle Eastern Arab countries. Participants' demographics and level of satisfaction with governmental responses to COVID-19 were analyzed and reported. Scores were benchmarked against 19 international values. RESULTS: A total of 7395 responses were included. Bahrain scored highest for satisfaction with the governmental response with 38.29 ± 2.93 on a scale of 40, followed by the Kingdom of Saudi Arabia (37.13 ± 3.27), United Arab Emirates (36.56 ± 3.44), Kuwait (35.74 ± 4.85), Jordan (23.08 ± 6.41), and Lebanon (15.39 ± 5.28). Participants' country of residence was a significant predictor of the satisfaction score (P < 0.001), and participants who suffered income reduction due to the pandemic, had a history of SARS-CoV-2 infection, and held higher educational degrees had significantly lower satisfaction scores (P < 0.001). When benchmarked with other international publics, countries from the Gulf Cooperation Council had the highest satisfaction level, Jordan had an average score, and Lebanon had one of the lowest satisfaction scores. CONCLUSION: The political crisis in Lebanon merged with the existing corruption were associated with the lowest public satisfaction score whereas the economical instability of Jordan placed the country just before the lowest position. On the other hand, the solid economy plus good planning and public trust in the government placed the other countries of the Gulf Cooperation Council on top of the scale. Further investigation is necessary to find out how the governments of other low-income countries may have handled the situation wisely and gained the trust of their publics. This may help convey a clearer picture to Arab governments that have suffered during the pandemic.


Assuntos
COVID-19 , Árabes , COVID-19/epidemiologia , Governo , Humanos , Líbano/epidemiologia , Pandemias , Satisfação Pessoal , SARS-CoV-2
11.
BMC Neurol ; 22(1): 102, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303829

RESUMO

BACKGROUND: Acute motor and sensory axonal neuropathy (AMSAN) is a subtype of Guillain-Barré syndrome (GBS) differentiated by nerve conduction studies (NCS) and characterized by symmetric ascending paralysis often involving respiratory muscles. While opsoclonus, which is involuntary chaotic rapid eye movements, is not a common manifestation of GBS. Moreover, little published data are available on the relation between liver enzymes elevation and GBS. CASE PRESENTATION: A 42-year-old man presented to Al Mouwassat University Hospital with weakness in all limbs and dyspnea. Examination showed an elevated respiratory rate, hyporeflexia, and decreased strength of upper and lower limbs. Analysis of cerebrospinal fluid revealed an albuminocyto-dissociation suggesting the diagnosis of GBS and subsequent plasmapheresis. NCS confirmed a diagnosis of AMSAN. Elevation in liver enzymes was noticed prompting further exploration with no positive findings. Despite treatment efforts, the patient developed severe dyspnea, deterioration in cognitive abilities, and opsoclonus with a normal brain MRI. Unfortunately, he developed respiratory failure which lead to his death. CONCLUSION: In this case, we highlight the occurrence of opsoclonus which is a rarely-encountered manifestation of GBS, in addition to an unexplained elevated liver enzyme, the thing that could contribute to larger research to further comprehend the pathophysiology of GBS.


Assuntos
Síndrome de Guillain-Barré , Transtornos da Motilidade Ocular , Doenças do Sistema Nervoso Periférico , Adulto , Síndrome de Guillain-Barré/complicações , Síndrome de Guillain-Barré/diagnóstico , Humanos , Fígado , Masculino , Exame Neurológico
12.
Nanomedicine (Lond) ; 17(24): 1891-1906, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36647807

RESUMO

The most important aspect of chemodynamic therapy (CDT) is the harnessing of Fenton or Fenton-like chemistry for cancer therapy within the tumor microenvironment, which occurs because of the moderate acidity and overexpressed H2O2 in the tumor microenvironment. Hydroxyl radicals (•OH) produced within tumor cells via Fenton and Fenton-like reactions cause cancer cell death. Reactive oxygen species-mediated CDT demonstrates a desired anticancer impact without the need for external stimulation or the development of drug resistance. Cancer therapy based on CDT is known as a viable cancer therapy modality. This review discusses the most recent CDT advancements and provides some typical instances. As a result, potential methods for further improving CDT efficiency under the guidance of Fenton chemistry are offered.


Cancer is one of the leading causes of death worldwide. Unfortunately, conventional treatments do not greatly increase the quality of life or survival rate of cancer patients. So, coming up with new, less invasive ways to treat cancer would be an important way to increase the number of cancer patients who survive. Chemodynamic therapy, a new cancer treatment modality, uses intracellular hydrogen peroxide as a fantastic 'Trojan horse' to produce highly toxic hydroxyl radicals (•OH) to kill cancer cells. This review discusses the most recent advancements in chemodynamic therapy and provides some typical instances.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Peróxido de Hidrogênio/metabolismo , Neoplasias/terapia , Nanoestruturas/uso terapêutico , Espécies Reativas de Oxigênio , Radical Hidroxila/metabolismo , Radical Hidroxila/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral , Nanopartículas/uso terapêutico
13.
Ann Med Surg (Lond) ; 67: 102473, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34178319

RESUMO

OBJECTIVE: Infertility is inadequately acknowledged as a problem in developing countries. Thyroid Autoimmunity (TAI) has been neatly investigated for its association with unfavorable pregnancy and reproductive consequences. We aim to evaluate Clinical Pregnancy Rate (CPR) as a primary outcome following In Vitro Fertilization/Intra Cytoplasmic Sperm Injection (IVF/ICSI) in women with Thyroid Autoimmunity (TAI). METHODS: A Retrospective cohort study included 584 women who underwent IVF/ICSI treatment between November 2012 and April 2017 in Orient Hospital, Damascus, Syria. Patients were tested for TAI before IVF/ICSI procedure. RESULTS: CPR did not significantly differ between TAI positive and TAI negative groups (p > 0.05). Subgroup analysis for only primary infertility patients showed a statistically significant difference in CPR between TAI positive and TAI negative groups. CONCLUSION: Although several arguments were in favor of the relation between IVF/ICSI outcomes and Thyroid autoimmune disease, the presence of TAI positivity did not adversely affect the clinical pregnancy rate.

14.
Front Cell Neurosci ; 15: 662453, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33867944

RESUMO

Sensing changes in the environment is crucial for survival. Animals from invertebrates to vertebrates use both visual and olfactory stimuli to direct survival behaviors including identification of food sources, finding mates, and predator avoidance. In primary sensory neurons there are signal transduction mechanisms that convert chemical or light signals into an electrical response through ligand binding or photoactivation of a receptor, that can be propagated to the olfactory and visual centers of the brain to create a perception of the odor and visual landscapes surrounding us. The fundamental principles of olfactory and phototransduction pathways within vertebrates are somewhat analogous. Signal transduction in both systems takes place in the ciliary sub-compartments of the sensory cells and relies upon the activation of G protein-coupled receptors (GPCRs) to close cyclic nucleotide-gated (CNG) cation channels in photoreceptors to produce a hyperpolarization of the cell, or in olfactory sensory neurons open CNG channels to produce a depolarization. However, while invertebrate phototransduction also involves GPCRs, invertebrate photoreceptors can be either ciliary and/or microvillar with hyperpolarizing and depolarizing responses to light, respectively. Moreover, olfactory transduction in invertebrates may be a mixture of metabotropic G protein and ionotropic signaling pathways. This review will highlight differences of the visual and olfactory transduction mechanisms between vertebrates and invertebrates, focusing on the implications to the gain of the transduction processes, and how they are modulated to allow detection of small changes in odor concentration and light intensity over a wide range of background stimulus levels.

15.
Ann Rheum Dis ; 80(1): 128-132, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33037005

RESUMO

BACKGROUND AND OBJECTIVE: Familial Mediterranean fever (FMF) is the most frequent hereditary autoinflammatory disease. Its diagnosis relies on a set of clinical criteria and a genetic confirmation on identification of biallelic pathogenic MEFV variants. MEFV encodes pyrin, an inflammasome sensor. Using a kinase inhibitor, UCN-01, we recently identified that dephosphorylation of FMF-associated pyrin mutants leads to inflammasome activation. The aim of this study was to assess whether quantifying UCN-01-mediated inflammasome activation could discriminate FMF patients from healthy donors (HD) and from patients with other inflammatory disorders (OID). METHODS: Real-time pyroptosis and IL-1ß secretion were monitored in response to UCN-01 in monocytes from FMF patients (n=67), HD (n=71) and OID patients (n=40). Sensitivity and specificity of the resulting diagnostic tests were determined by receiver operating characteristic curve analyses. RESULTS: Inflammasome monitoring in response to UCN-01 discriminates FMF patients from other individuals. Pyroptosis assessment leads to a fast FMF diagnosis while combining pyroptosis and IL-1ß dosage renders UCN-01-based assays highly sensitive and specific. UCN-01-triggered monocytes responses were influenced by MEFV gene dosage and MEFV mutations in a similar way as clinical phenotypes are. CONCLUSIONS: UCN-01-based inflammasome assays could be used to rapidly diagnose FMF, with high sensitivity and specificity.


Assuntos
Febre Familiar do Mediterrâneo/diagnóstico , Inflamassomos/efeitos dos fármacos , Interleucina-1beta/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Pirina/efeitos dos fármacos , Piroptose/efeitos dos fármacos , Estaurosporina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Juvenil/diagnóstico , Síndrome de Behçet/diagnóstico , Estudos de Casos e Controles , Criança , Pré-Escolar , Síndromes Periódicas Associadas à Criopirina/diagnóstico , Febre Familiar do Mediterrâneo/genética , Febre Familiar do Mediterrâneo/imunologia , Feminino , Febre/diagnóstico , Febre de Causa Desconhecida/diagnóstico , Doenças Hereditárias Autoinflamatórias/diagnóstico , Humanos , Testes Imunológicos/métodos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Deficiência de Mevalonato Quinase/diagnóstico , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Pirina/genética , Pirina/imunologia , Pirina/metabolismo , Sensibilidade e Especificidade , Sepse/diagnóstico , Estaurosporina/farmacologia , Doença de Still de Início Tardio/diagnóstico , Adulto Jovem
16.
Sci Rep ; 10(1): 16041, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994451

RESUMO

Rods and cones use intracellular Ca2+ to regulate many functions, including phototransduction and neurotransmission. The Mitochondrial Calcium Uniporter (MCU) complex is thought to be the primary pathway for Ca2+ entry into mitochondria in eukaryotes. We investigate the hypothesis that mitochondrial Ca2+ uptake via MCU influences phototransduction and energy metabolism in photoreceptors using a mcu-/- zebrafish and a rod photoreceptor-specific Mcu-/- mouse. Using genetically encoded Ca2+ sensors to directly examine Ca2+ uptake in zebrafish cone mitochondria, we found that loss of MCU reduces but does not eliminate mitochondrial Ca2+ uptake. Loss of MCU does not lead to photoreceptor degeneration, mildly affects mitochondrial metabolism, and does not alter physiological responses to light, even in the absence of the Na+/Ca2+, K+ exchanger. Our results reveal that MCU is dispensable for vertebrate photoreceptor function, consistent with its low expression and the presence of an alternative pathway for Ca2+ uptake into photoreceptor mitochondria.


Assuntos
Canais de Cálcio/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Animais , Transporte Biológico , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Células Fotorreceptoras/metabolismo , Trocador de Sódio e Cálcio/genética , Trocador de Sódio e Cálcio/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
17.
Cell Death Differ ; 27(3): 1067-1085, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31371786

RESUMO

Photoreceptors are specialized neurons that rely on Ca2+ to regulate phototransduction and neurotransmission. Photoreceptor dysfunction and degeneration occur when intracellular Ca2+ homeostasis is disrupted. Ca2+ homeostasis is maintained partly by mitochondrial Ca2+ uptake through the mitochondrial Ca2+ uniporter (MCU), which can influence cytosolic Ca2+ signals, stimulate energy production, and trigger apoptosis. Here we discovered that zebrafish cone photoreceptors express unusually low levels of MCU. We expected that this would be important to prevent mitochondrial Ca2+ overload and consequent cone degeneration. To test this hypothesis, we generated a cone-specific model of MCU overexpression. Surprisingly, we found that cones tolerate MCU overexpression, surviving elevated mitochondrial Ca2+ and disruptions to mitochondrial ultrastructure until late adulthood. We exploited the survival of MCU overexpressing cones to additionally demonstrate that mitochondrial Ca2+ uptake alters the distributions of citric acid cycle intermediates and accelerates recovery kinetics of the cone response to light. Cones adapt to mitochondrial Ca2+ stress by decreasing MICU3, an enhancer of MCU-mediated Ca2+ uptake, and selectively transporting damaged mitochondria away from the ellipsoid toward the synapse. Our findings demonstrate how mitochondrial Ca2+ can influence physiological and metabolic processes in cones and highlight the remarkable ability of cone photoreceptors to adapt to mitochondrial stress.


Assuntos
Adaptação Fisiológica , Cálcio/metabolismo , Luz , Metaboloma , Mitocôndrias/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Estresse Fisiológico , Adaptação Fisiológica/efeitos da radiação , Animais , Canais de Cálcio/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Isocitrato Desidrogenase/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Cinética , Transdução de Sinal Luminoso/efeitos da radiação , Mitocôndrias/efeitos da radiação , Mitocôndrias/ultraestrutura , Modelos Biológicos , Fenótipo , Células Fotorreceptoras Retinianas Cones/efeitos da radiação , Células Fotorreceptoras Retinianas Cones/ultraestrutura , Estresse Fisiológico/efeitos da radiação , Peixe-Zebra
18.
Cureus ; 11(8): e5315, 2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31592370

RESUMO

Introduction Thyroid autoimmune (TAI) disease with a prevalence varying between 5 and 15%, represents the most common endocrine disorder in women with reproductive age. Not only is TAI disease five to 10 folds more common in women than men but also TAI diseases is often undiagnosed because it may be present without overt thyroid dysfunction for several years. Studies found an increased prevalence of TAI in women referred to fertility clinics compared with normal population. In this analysis we aimed to study the prevalence of TAI among women seeking fertility care in Damascus, Syria in order to understand its clinical and public health importance in population. Methods This study is a retrospective cross-sectional study on women patients seeking fertility care at Orient Hospital, Damascus city, Syria from April 2011 to March 2018. A total of 2526 women, with available biochemical data of anti-thyroid antibodies (anti-TPO) and anti-thyroglobulin antibodies (anti-TG) were included in our study. Thyroid stimulating hormone (TSH) titers data were also included in the statistical analysis. Results TAI was found positive in 559 patients (22.1%) of our studies population. TAI was more prevalent in patients with abnormal TSH levels. Conclusion Thyroid autoimmunity prevalence in women seeking fertility care in Damascus, Syria was 22.1% which is significantly higher than normal population. Further studies are needed to assess the relation of these antibodies in thyroid, gynecological and other factors for the Syrian population.

19.
Int J Clin Oncol ; 24(2): 153-160, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30242539

RESUMO

OBJECTIVE: To evaluate the survival and functional outcome of patients with brain metastasis due to gestational trophoblastic neoplasia (GTN). METHODS: A 17-year retrospective study based on case review of women with brain metastasis from GTN identified by the electronic databases held in the French Reference Centre. PRIMARY OUTCOME MEASURE: 5-year overall survival calculated with the Kaplan-Meier method. SECONDARY OUTCOME MEASURES: causes of death, prognostic factors and functional outcomes. RESULTS: 21 patients had GTN brain metastasis and were treated with multidrug chemotherapy without concomitant whole-brain radiation therapy. Three patients died early (< 4 weeks) of cerebral hemorrhage, 3 died ≥ 1 months after treatment initiation and 15 were alive at the date of last contact. The overall survival rate at 5 years was 69.8% (95% CI 44.3-85.3). After excluding early deaths, the survival rate at 5 years was 81.5% (95% CI 52.3-93.7). No predictive factor of survival was identified. Although 11 of the 12 (92%) surviving patients contacted still reported sequelae, nine of them (75%) had resumed a normal life. CONCLUSIONS: After excluding early deaths, this study implies a high survival rate in patients with brain metastasis from GTN. These results were achieved in the total absence of whole-brain radiotherapy and almost completely without the need for intrathecal methotrexate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/secundário , Coriocarcinoma/patologia , Doença Trofoblástica Gestacional/patologia , Neoplasias Uterinas/patologia , Adolescente , Adulto , Neoplasias Encefálicas/tratamento farmacológico , Coriocarcinoma/tratamento farmacológico , Feminino , Doença Trofoblástica Gestacional/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Gravidez , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias Uterinas/tratamento farmacológico , Adulto Jovem
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