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1.
Front Physiol ; 15: 1368054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660538

RESUMO

Myosins of class VI move toward the minus-end of actin filaments and play vital roles in cellular processes such as endocytosis, autophagy, protein secretion, and the regulation of actin filament dynamics. In contrast to the majority of metazoan organisms examined to date which contain a single MYO6 gene, C. elegans, possesses two MYO6 homologues, SPE-15/HUM-3 and HUM-8. Through a combination of in vitro biochemical/biophysical analysis and cellular assays, we confirmed that both SPE-15/HUM-3 and HUM-8 exhibit reverse directionality, velocities, and ATPase activity similar to human MYO6. Our characterization also revealed that unlike SPE-15/HUM-3, HUM-8 is expressed as two distinct splice isoforms, one with an additional unique 14 amino acid insert in the cargo-binding domain. While lipid and adaptor binding sites are conserved in SPE-15/HUM-3 and HUM-8, this conservation does not enable recruitment to endosomes in mammalian cells. Finally, we performed super-resolution confocal imaging on transgenic worms expressing either mNeonGreen SPE-15/HUM-3 or wrmScarlet HUM-8. Our results show a clear distinction in tissue distribution between SPE-15/HUM-3 and HUM-8. While SPE-15/HUM-3 exhibited specific expression in the gonads and neuronal tissue in the head, HUM-8 was exclusively localized in the intestinal epithelium. Overall, these findings align with the established tissue distributions and localizations of human MYO6.

2.
bioRxiv ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38352353

RESUMO

The process of aging is defined by the breakdown of critical maintenance pathways leading to an accumulation of damage and its associated phenotypes. Aging affects many systems and is considered the greatest risk factor for a number of diseases. Therefore, interventions aimed at establishing resilience to aging should delay or prevent the onset of age-related diseases. Recent studies have shown a three-drug cocktail consisting of rapamycin, acarbose, and phenylbutyrate delayed the onset of physical, cognitive, and biological aging phenotypes in old mice. To test the ability of this drug cocktail to impact Alzheimer's disease (AD), an adeno-associated-viral vector model of AD was created. Mice were fed the drug cocktail 2 months prior to injection and allowed 3 months for phenotypic development. Cognitive phenotypes were evaluated through a spatial navigation learning task. To quantify neuropathology, immunohistochemistry was performed for AD proteins and pathways of aging. Results suggested the drug cocktail was able to increase resilience to cognitive impairment, inflammation, and AD protein aggregation while enhancing autophagy and synaptic integrity, preferentially in female cohorts. In conclusion, female mice were more susceptible to the development of early stage AD neuropathology and learning impairment, and more responsive to treatment with the drug cocktail in comparison to male mice. Translationally, a model of AD where females are more susceptible would have greater value as women have a greater burden and incidence of disease compared to men. These findings validate past results and provide the rationale for further investigations into enhancing resilience to early-stage AD by enhancing resilience to aging.

3.
BMJ Open ; 14(1): e077743, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216203

RESUMO

PURPOSE: The National Congenital Anomaly and Rare Disease Registration Service (NCARDRS), part of National Disease Registration Service in National Health Service England, quality assures, curates and analyses individual data on the pregnancies, fetuses, babies, children and adults with congenital anomalies and rare diseases across England. The congenital anomaly (CA) register provides a resource for patients and their families, clinicians, researchers and public health professionals in furthering the understanding of CAs. PARTICIPANTS: NCARDRS registers CAs occurring in babies born alive and stillborn, fetal losses and terminations in England. NCARDRS collects data from secondary and tertiary healthcare providers, private providers and laboratories covering fetal medicine, maternity or paediatric services. Data describe the pregnancy, mother, baby and anomaly. Established in 2015, NCARDRS expanded CA registration coverage from 22% of total births in England in 2015 to national coverage, which was achieved in 2018. Prior to 2015, data collection was performed independently by regional registers in England; these data are also held by NCARDRS. FINDINGS TO DATE: NCARDRS registers approximately 21 000 babies with CAs per year with surveillance covering around 600 000 total births, the largest birth coverage for a CA register globally. Data on prevalence, risk factors and survival for children with CAs are available. Data have been used in several peer-reviewed publications. Birth prevalence statistics, including public health indicators such as the association with maternal age, infant and perinatal mortality, are published annually. NCARDRS supports clinical audit for screening programmes and service evaluation. FUTURE PLANS: NCARDRS provides a valuable resource for the understanding of the epidemiology, surveillance, prevention and treatment of CAs. Currently, approximately 21 000 new registrations of babies or fetuses with suspected or confirmed CAs are added each year. Identifiers are collected, enabling linkage to routinely collected healthcare and population statistics, further enhancing the value of the data.


Assuntos
Anormalidades Congênitas , Medicina Estatal , Lactente , Adulto , Criança , Humanos , Gravidez , Feminino , Coleta de Dados , Natimorto , Idade Materna , Inglaterra/epidemiologia , Anormalidades Congênitas/epidemiologia
4.
Arch Dis Child ; 109(4): 287-291, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38123921

RESUMO

BACKGROUND: Chest X-ray (CXR) has typically been the main investigation in children with suspected respiratory pathology. Recent advances in lung point-of-care ultrasound (POCUS) have shown the potential for it to be comparative, if not better, than CXR. The objective of this study was to compare CXR with lung POCUS in children with respiratory illness in a ward-based setting at a paediatric teaching hospital. METHODS: Any child <18 years of age presenting to Southampton Children's Hospital requiring a CXR for clinical reasons also had lung POCUS performed. CXR was reported by a consultant paediatric radiologist and lung POCUS was reviewed retrospectively by a blinded POCUS clinician, with only the clinical information provided on the CXR request. Comparisons were made between the CXR and lung POCUS findings. RESULTS: 100 paired lung POCUS and CXR were included in the study. 30% of lung POCUS were normal with 97% of these having a normal CXR. 70% of cases had POCUS abnormalities with 96% of POCUS cases identifying comparative lung pathology. Lung POCUS therefore had a sensitivity of 98.51% and a specificity of 87.9% with a diagnostic accuracy of 95% when compared with the CXR report. CONCLUSIONS: Lung POCUS has excellent diagnostic accuracy. The diagnosis of normal lung on POCUS when performed by a trained practitioner can reliably reduce the need for a CXR, thus reducing CXR use and radiation exposure in children. An abnormal lung POCUS could then either give the diagnosis or lead to a CXR with the expectation of clinically relevant findings.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Vigília , Humanos , Criança , Estudos Retrospectivos , Pulmão/diagnóstico por imagem , Ultrassonografia
5.
STAR Protoc ; 4(4): 102635, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805920

RESUMO

Perceptual measures of odor threshold provide a mechanism to compare sensitivity across species and to gauge stimulus concentrations for functional experiments. Here, we present a protocol to precisely quantify the odor detection threshold of mice. We describe the construction of a head-fixed operant conditioning behavioral rig and provide details of the training and testing procedures. This approach can be used to compare the sensitivity of mice across odorants and to quantify detection differences associated with genetic mutations or pharmacological manipulations. For complete details on the use and execution of this protocol, please refer to Johnson et al. (2023),1 Jennings et al. (2022),2 Williams and Dewan (2020),3 and Dewan et al. (2018).4.

6.
Function (Oxf) ; 4(6): zqad050, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37753180

RESUMO

Red blood cell (RBC) trapping is common in ischemic acute kidney injury (AKI) and presents as densely packed RBCs that accumulate within and engorge the kidney medullary circulation. In this study, we tested the hypothesis that "RBC trapping directly promotes tubular injury independent of extending ischemia time." Studies were performed on rats. Red blood cell congestion and tubular injury were compared between renal arterial clamping, venous clamping, and venous clamping of blood-free kidneys. Vessels were occluded for either 15 or 45 min with and without reperfusion. We found that RBC trapping in the medullary capillaries occurred rapidly following reperfusion from renal arterial clamping and that this was associated with extravasation of blood from congested vessels, uptake of blood proteins by the tubules, and marked tubular injury. To determine if this injury was due to blood toxicity or an extension of ischemia time, we compared renal venous and arterial clamping without reperfusion. Venous clamping resulted in RBC trapping and marked tubular injury within 45 min of ischemia. Conversely, despite the same ischemia time, RBC trapping and tubular injury were minimal following arterial clamping without reperfusion. Confirming the role of blood toward tubular injury, injury was markedly reduced in blood-free kidneys with venous clamping. Our data demonstrate that RBC trapping results in the rapid extravasation and uptake of blood components by tubular cells, causing toxic tubular injury. Tubular toxicity from extravasation of blood following RBC trapping appears to be a major component of tubular injury in ischemic AKI, which has not previously been recognized.


Assuntos
Injúria Renal Aguda , Lesões do Sistema Vascular , Animais , Ratos , Eritrócitos , Rim , Isquemia
9.
Horm Behav ; 148: 105302, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36628861

RESUMO

Genetic knockouts of the vasopressin receptor 1a (Avpr1a), oxytocin receptor (Oxtr), or oxytocin (Oxt) gene in mice have helped cement the causal relationship between these neuropeptide systems and various social behaviors (e.g., social investigation, recognition, and communication, as well as territoriality and aggression). In mice, these social behaviors depend upon the olfactory system. Thus, it is critical to assess the olfactory capabilities of these knockout models to accurately interpret the observed differences in social behavior. Prior studies utilizing these transgenic mice have sought to test for baseline deficits in olfactory processing; predominantly through use of odor habituation/dishabituation tasks, buried food tests, or investigation assays using non-social odorants. While informative, these assays rely on the animal's intrinsic motivation and locomotor behavior to measure olfactory capabilities and thus, often yield mixed results. Instead, psychophysical analyses using operant conditioning procedures and flow-dilution olfactometry are ideally suited to precisely quantify olfactory perception. In the present study, we used these methods to assess the main olfactory capabilities of adult male and female Avpr1a, Oxtr, and Oxt transgenic mice to volatile non-social odorants. Our results indicate that homozygous and heterozygous knockout mice of all three strains have the same sensitivity and discrimination ability as their wild-type littermates. These data strongly support the hypothesis that the observed social deficits of these global knockout mice are not due to baseline deficits of their main olfactory system.


Assuntos
Ocitocina , Receptores de Ocitocina , Camundongos , Masculino , Feminino , Animais , Receptores de Ocitocina/genética , Odorantes , Receptores de Vasopressinas/genética , Comportamento Social , Camundongos Transgênicos , Camundongos Knockout
10.
Qual Life Res ; 32(5): 1329-1340, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35867321

RESUMO

PURPOSE: This study explored perceptions of meaningful weight-loss and the level of change on two patient-reported outcome (PRO) measures, the 36-item Short Form Health Survey® [SF-36v2®] and Impact of Weight on Quality of Life Lite-Clinical Trials© [IWQOL-Lite-CT©], that individuals living with overweight or obesity consider to be meaningful and indicative of treatment success. METHODS: Thirty-three qualitative interviews were conducted in the US with adults living with overweight or obesity. Concept elicitation explored perceptions of minimally important/meaningful weight-loss using open-ended questions. Cognitive debriefing was used to understand thresholds for meaningful change on both measures. RESULTS: Most participants (n = 23/33) expected a 5% total body weight-loss to yield some benefit in physical functioning, while all participants expected a 10% weight-loss to provide a meaningful and noticeable improvement in their physical functioning. Participants indicated that an item-level 1-point score change on each measure would represent a noticeable improvement in physical functioning and indicate treatment success. CONCLUSIONS: Participants expected moderate weight-losses to be noticeable, with ≥ 10% weight-loss yielding the most consistent results. The findings suggested that both measures provide strong opportunity to demonstrate treatment benefit in relation to physical functioning as a small change on the response scale would represent a noticeable improvement in participants' daily lives.


Assuntos
Sobrepeso , Qualidade de Vida , Adulto , Humanos , Qualidade de Vida/psicologia , Obesidade/terapia , Obesidade/psicologia , Redução de Peso , Resultado do Tratamento
11.
Biomolecules ; 12(12)2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36551317

RESUMO

Unconventional myosins are a superfamily of actin-based motor proteins that perform a number of roles in fundamental cellular processes, including (but not limited to) intracellular trafficking, cell motility, endocytosis, exocytosis and cytokinesis. 40 myosins genes have been identified in humans, which belong to different 12 classes based on their domain structure and organisation. These genes are widely expressed in different tissues, and mutations leading to loss of function are associated with a wide variety of pathologies while over-expression often results in cancer. Caenorhabditis elegans (C. elegans) is a small, free-living, non-parasitic nematode. ~38% of the genome of C. elegans has predicted orthologues in the human genome, making it a valuable tool to study the function of human counterparts and human diseases. To date, 8 unconventional myosin genes have been identified in the nematode, from 6 different classes with high homology to human paralogues. The hum-1 and hum-5 (heavy chain of an unconventional myosin) genes encode myosin of class I, hum-2 of class V, hum-3 and hum-8 of class VI, hum-6 of class VII and hum-7 of class IX. The hum-4 gene encodes a high molecular mass myosin (307 kDa) that is one of the most highly divergent myosins and is a member of class XII. Mutations in many of the human orthologues are lethal, indicating their essential properties. However, a functional characterisation for many of these genes in C. elegans has not yet been performed. This article reviews the current knowledge of unconventional myosin genes in C. elegans and explores the potential use of the nematode to study the function and regulation of myosin motors to provide valuable insights into their role in diseases.


Assuntos
Caenorhabditis elegans , Miosinas , Animais , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Miosinas/genética , Miosinas/metabolismo , Actinas/metabolismo , Movimento Celular
12.
Semin Nephrol ; 42(3): 151280, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-36460572

RESUMO

Acute kidney injury (AKI) represents a sudden reduction in renal function and is a major clinical problem with a high mortality rate. Despite decades of research, there are currently no direct therapies for AKI. The failure of therapeutic approaches identified in rodents to translate to human beings has led to questions regarding the appropriateness of these models. Our recent data indicate that there are two distinct processes driving tubular injury in the commonly used rat model of warm bilateral renal ischemia reperfusion injury, which often is used to mimic ischemic AKI. One results from the period of warm ischemia, manifesting as sublethal injury and coagulative necrosis of the proximal tubules in the renal cortex. This is the predominate type of injury observed 24 hours after reperfusion and the most well studied. The other results from red blood cell congestion of the outer medullary vasculature. This type of injury manifests as cell sloughing, along with the later formation of heme casts that fill distal nephron segments. Cell sloughing from congestion is most prominent in the early hours after reperfusion and often is masked by regeneration of the tubular epithelium by 24 hours postischemia. In this review, we argue that injury from outer medullary red blood cell congestion reflects the pathology observed in human kidneys and likely is representative of injury in most cases of ischemic AKI after shock. Greater focus on this congestive injury is likely to lead to improved translation in AKI.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Ratos , Humanos , Animais , Rim/metabolismo , Injúria Renal Aguda/metabolismo , Isquemia/complicações , Traumatismo por Reperfusão/metabolismo , Eritrócitos/metabolismo , Eritrócitos/patologia
14.
Orphanet J Rare Dis ; 17(1): 182, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525989

RESUMO

BACKGROUND: This study aimed to identify fit-for-purpose clinical outcome assessments (COAs) to evaluate physical function, as well as social and emotional well-being in clinical trials enrolling a pediatric population with achondroplasia. Qualitative interviews lasting up to 90 min were conducted in the US with children/adolescents with achondroplasia and/or their caregivers. Interviews utilized concept elicitation methodology to explore experiences and priorities for treatment outcomes. Cognitive debriefing methodology explored relevance and understanding of selected COAs. RESULTS: Interviews (N = 36) were conducted with caregivers of children age 0-2 years (n = 8) and 3-7 years (n = 7) and child/caregiver dyads with children age 8-11 years (n = 15) and 12-17 years (n = 6). Children/caregivers identified pain, short stature, impacts on physical functioning, and impacts on well-being (e.g. negative attention/comments) as key bothersome aspects of achondroplasia. Caregivers considered an increase in height (n = 9/14, 64%) and an improvement in limb proportion (n = 11/14, 71%) as successful treatment outcomes. The Childhood Health Assessment Questionnaire (CHAQ) and Quality of Life in Short Stature Youth (QoLISSY-Brief) were cognitively debriefed. CHAQ items evaluating activities, reaching, and hygiene were most relevant. QoLISSY-Brief items evaluating reaching, height bother, being treated differently, and height preventing doing things others could were most relevant. The CHAQ and QoLISSY-Brief instructions, item wording, response scales/options and recall period were well understood by caregivers and adolescents age 12-17. Some children aged 8-11 had difficulty reading, understanding, or required caregiver input. Feedback informed minor amendments to the CHAQ and the addition of a 7-day recall period to the QoLISSY-Brief. These amendments were subsequently reviewed and confirmed in N = 12 interviews with caregivers of children age 0-11 (n = 9) and adolescents age 12-17 (n = 3). CONCLUSIONS: Achondroplasia impacts physical functioning and emotional/social well-being. An increase in height and improvement in limb proportion are considered to be important treatment outcomes, but children/adolescents and their caregivers expect that a successful treatment should also improve important functional outcomes such as reach. The CHAQ (adapted for achondroplasia) and QoLISSY-Brief are relevant and appropriate measures of physical function and emotional/social well-being for pediatric achondroplasia trials; patient-report is recommended for age 12-17 years and caregiver-report is recommended for age 0-11 years.


Assuntos
Acondroplasia , Qualidade de Vida , Adolescente , Cuidadores/psicologia , Criança , Ensaios Clínicos como Assunto , Família , Humanos , Qualidade de Vida/psicologia , Inquéritos e Questionários , Resultado do Tratamento
15.
Ther Adv Endocrinol Metab ; 13: 20420188211065655, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035873

RESUMO

BACKGROUND: Long-chain fatty acid oxidation disorders (LC-FAOD) are a group of rare autosomal-recessive genetic disorders characterized by metabolic deficiencies in which the body is unable to convert long-chain fatty acids into energy. To date, however, there is limited understanding of the patient experience of LC-FAOD. METHODS: The symptoms, observable signs, and quality of life (QoL) impacts associated with LC-FAOD were explored via a focus group (n = 8) and semi-structured interviews (n = 6) with patients and caregivers of patients with LC-FAOD, and interviews (n = 4) with expert clinicians. Data were analyzed via thematic analysis and summarized in a conceptual model. RESULTS: Participants reported a wide range of signs and symptoms associated with LC-FAOD, broadly categorized as musculoskeletal, endocrine/nutritional/metabolic, neurological, gastrointestinal/digestive, sensory, cardiovascular, respiratory, urological, and constitutional. LC-FAOD were reported to have a significant impact on various aspects of patients' lives including physical functioning, participation in daily activities, emotional/psychological wellbeing, and social functioning. Lifestyle modifications (such as diet and exercise restrictions) were necessary because of the condition. Symptoms were typically episodic in presentation often arising or exacerbated during catabolic conditions such as prolonged exercise, fasting, physiological stress, and illness/infection. Symptoms were also commonly reported to lead to emergency room visits, hospitalization, and clinical complications. CONCLUSION: LC-FAOD have a considerable impact on patients' lives. There is a high degree of concordance in the signs, symptoms, and impacts of LC-FAOD reported by patients, caregivers, and clinicians; however, there were many symptoms and impacts that were only reported by patients and caregivers, thus demonstrating that insights from patient/caregiver experience data are integral for informing medical product development and facilitating patient-centered care.

16.
Aging Pathobiol Ther ; 4(4): 98-99, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36644127

RESUMO

The descriptive term "normal" aging is often used in scientific literature to indicate commonly occurring changes with increasing age in the absence of overt disease. However, significant molecular and geropathological changes are increasingly present to indicate there is nothing normal about aging. Thus, the term "normal" aging is scientifically incorrect. There are changes in multiple genetic and epigenetic processes and pathways that drive aging, and some individuals are more resilient to these changes than others. Thus, "resilient" aging would be a more correct term to represent a major emphasis on investigating mechanisms and therapeutic targets for resilience, rather than a label of "normal" aging that is misleading and currently receives relatively little attention.

17.
J Patient Rep Outcomes ; 5(1): 114, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34731344

RESUMO

BACKGROUND: Presbyopia is defined as the age-related deterioration in the ability to focus on close objects, causing difficulty with near vision tasks. The study aim was to understand the lived experience of phakic presbyopia and identify all relevant visual function symptoms and associated functional impacts. METHODS: Fifty individuals with clinician-confirmed phakic presbyopia (US n = 30, France n = 10, Germany n = 10) and seven healthcare professionals (HCPs) participated in in-depth, face-to-face, qualitative concept elicitation interviews. Verbatim transcripts were analyzed using thematic analysis methods. RESULTS: Visual function symptoms reported by participants with phakic presbyopia were categorized as: primary near vision functioning symptoms (impaired near visual acuity, n = 50/50, 100%; difficulty with near vision in dim light, n = 42/50, 84%; difficulty focusing at close distances, n = 30/50, 60%; difficulty seeing things when glare is present, n = 30/50, 60%) and secondary symptoms (eye strain, n = 37/50, 74%; dry eyes, n = 35/50, 70%; headaches, n = 30/50, 60%). Proximal impacts on functional vision included difficulty reading in near vision (n = 49/50, 98%, including printed text and handwriting), seeing objects in near vision n = 48/50, 96%, and performing activities of daily living that require near vision (n = 49/50, 98%, including using a smartphone or computer). Distal impacts on functional vision included emotional, work, financial and social impacts. HCP interviews supported participant findings. CONCLUSION: Findings provide a comprehensive understanding of the lived experience of phakic presbyopia which informed the development of a presbyopia conceptual model and patient-reported outcome assessments of vision correction independence and near vision functioning. The sample did not include those whose vision cannot be adequately corrected with lenses or surgery.

18.
Front Pharmacol ; 12: 746385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621175

RESUMO

Tumors with elevated c-Myc expression often exhibit a highly aggressive phenotype, and c-Myc amplification has been shown to be frequent in esophageal cancer. Emerging data suggests that synthetic lethal interactions between c-Myc pathway activation and small molecules inhibition involved in cell cycle signaling can be therapeutically exploited to preferentially kill tumor cells. We therefore investigated whether exploiting elevated c-Myc expression is effective in treating esophageal cancer with the CDK inhibitor flavopiridol. We found frequent overexpression of c-Myc in human esophageal cancer cell lines and tissues. c-Myc overexpression correlated with accelerated esophageal cancer subcutaneous xenograft tumor growth. Esophageal cancer cells with elevated c-Myc expression were found preferentially more sensitive to induction of apoptosis by the CDK inhibition flavopiridol compared to esophageal cancer cells with lower c-Myc expression. In addition, we observed that flavopiridol alone or in combination with the chemotherapeutic agent nanoparticle albumin-bound paclitaxel (NPT) or in combinations with the targeted agent BMS-754807 significantly inhibited esophageal cancer cell proliferation and subcutaneous xenograft tumor growth while significantly enhancing overall mice survival. These results indicate that aggressive esophageal cancer cells with elevated c-Myc expression are sensitive to the CDK inhibitor flavopiridol, and that flavopiridol alone or in combination can be a potential therapy for c-Myc overexpressing esophageal cancer.

19.
Cell Mol Life Sci ; 78(23): 7309-7337, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34704115

RESUMO

Human atrial and ventricular contractions have distinct mechanical characteristics including speed of contraction, volume of blood delivered and the range of pressure generated. Notably, the ventricle expresses predominantly ß-cardiac myosin while the atrium expresses mostly the α-isoform. In recent years exploration of the properties of pure α- & ß-myosin isoforms have been possible in solution, in isolated myocytes and myofibrils. This allows us to consider the extent to which the atrial vs ventricular mechanical characteristics are defined by the myosin isoform expressed, and how the isoform properties are matched to their physiological roles. To do this we Outline the essential feature of atrial and ventricular contraction; Explore the molecular structural and functional characteristics of the two myosin isoforms; Describe the contractile behaviour of myocytes and myofibrils expressing a single myosin isoform; Finally we outline the outstanding problems in defining the differences between the atria and ventricles. This allowed us consider what features of contraction can and cannot be ascribed to the myosin isoforms present in the atria and ventricles.


Assuntos
Átrios do Coração/metabolismo , Ventrículos do Coração/metabolismo , Contração Miocárdica/fisiologia , Miócitos Cardíacos/fisiologia , Miosinas Ventriculares/metabolismo , Sequência de Aminoácidos , Função Atrial/fisiologia , Pressão Sanguínea/fisiologia , Humanos , Miócitos Cardíacos/metabolismo , Miofibrilas/fisiologia , Domínios Proteicos , Isoformas de Proteínas , Função Ventricular/fisiologia
20.
J Patient Rep Outcomes ; 5(1): 109, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34689253

RESUMO

BACKGROUND: Presbyopia is the age-related deterioration in the ability to focus on close objects. In order to develop a patient-reported outcome (PRO) instrument to assess near vision functioning, the Near Activity Visual Questionnaire (NAVQ) was adapted to incorporate modern technology (e.g. smartphones) and to be appropriate for use in phakic presbyopia, leading to the development of the NAVQ-Presbyopia (NAVQ-P). Additional single-item instruments of near vision correction independence (NVCI), correction preference (NVCP), and vision satisfaction (NVS) were also developed. The study aimed to evaluate the content validity of the NAVQ-P and additional instruments in individuals with phakic presbyopia. METHODS: Participants in the US (n = 15), Germany (n = 10) and France (n = 10) took part in face-to-face, qualitative, cognitive debriefing interviews. Seven healthcare professionals (HCPs) were also interviewed to assess the clinical relevance of the PRO instruments. Interviews started with open-ended qualitative concept elicitation questioning; participants then completed the PRO instruments on an electronic tablet using a "think-aloud" process and were asked about their understanding and relevance of each item, instruction, response scale and recall period. Interviews were conducted in two rounds allowing for modifications between rounds. RESULTS: The participants interpreted the majority of the PRO instruments and recall period correctly and consistently. They were able to select an appropriate response option without difficulty. Minor modifications were made to the PRO instruments based on interview findings. Instruction/item wording was modified to include reference to use of a magnifying glass, in addition to glasses and contact lenses. Two items were added to assess difficulty with precision tasks (e.g. sewing) and taking longer to adjust from distance to near vision. HCPs confirmed the relevance of the concepts being measured for presbyopia and recommended the addition of an item assessing contrast sensitivity. CONCLUSIONS: Developed in accordance with the FDA PRO Guidance, the findings support content validity of the NAVQ-P as a suitable, well-understood instrument of relevant near vision functioning concepts in individuals with phakic presbyopia. The NVCI and additional PRO instruments are appropriate to assess near vision correction independence, correction preference, and vision satisfaction. Future work will assess the psychometric properties of the NAVQ-P and additional PRO instruments.

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