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1.
Hum Gene Ther ; 34(15-16): 682-696, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37376759

RESUMO

Neurodegeneration and cerebrovascular disease share an underlying microvascular dysfunction that may be remedied by selective transgene delivery. To date, limited options exist in which cellular components of the brain vasculature can be effectively targeted by viral vector therapeutics. In this study, we characterize the first engineered adeno-associated virus (AAV) capsid mediating high transduction of cerebral vascular pericytes and smooth muscle cells (SMCs). We performed two rounds of in vivo selection with an AAV capsid scaffold displaying a heptamer peptide library to isolate capsids that traffic to the brain after intravenous delivery. One identified capsid, termed AAV-PR, demonstrated high transduction of the brain vasculature, in contrast to the parental capsid, AAV9, which transduces mainly neurons and astrocytes. Further analysis using tissue clearing, volumetric rendering, and colocalization revealed that AAV-PR enabled high transduction of cerebral pericytes located on small-caliber vessels and SMCs in the larger arterioles and penetrating pial arteries. Analysis of tissues in the periphery indicated that AAV-PR also transduced SMCs in large vessels associated with the systemic vasculature. AAV-PR was also able to transduce primary human brain pericytes with higher efficiency than AAV9. Compared with previously published AAV capsids tropisms, AAV-PR represents the first capsid to allow for effective transduction of brain pericytes and SMCs and offers the possibility of genetically modulating these cell types in the context of neurodegeneration and other neurological diseases.


Assuntos
Capsídeo , Dependovirus , Humanos , Capsídeo/metabolismo , Dependovirus/metabolismo , Transdução Genética , Pericitos/metabolismo , Proteínas do Capsídeo/metabolismo , Encéfalo/metabolismo , Miócitos de Músculo Liso/metabolismo , Vetores Genéticos/genética
2.
Contemp Clin Trials ; 124: 107030, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36519749

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICI) have revolutionised treating advanced cancers. ICI are administered intravenously every 2-6 weeks for up to 2 years, until cancer progression/unacceptable toxicity. Physiological efficacy is observed at lower doses than those used as standard of care (SOC). Pharmacodynamic studies indicate sustained target occupancy, despite a pharmacological half-life of 2-3 weeks. Reducing frequency of administration may be possible without compromising outcomes. The REFINE trial aims to limit individual patient exposure to ICI whilst maintaining efficacy, with potential benefits in quality of life and reduced drug treatment/attendance costs. METHODS/DESIGN: REFINE is a randomised phase II, multi-arm, multi-stage (MAMS) adaptive basket trial investigating extended interval administration of ICIs. Eligible patients are those responding to conventionally dosed ICI at 12 weeks. In stage I, patients (n = 160 per tumour-specific cohort) will be randomly allocated (1:1) to receive maintenance ICI at SOC vs extended dose interval. REFINE is currently recruiting UK patients with locally advanced or metastatic renal cell carcinoma (RCC) who have tolerated and responded to initial nivolumab/ipilimumab, randomised to receive maintenance nivolumab SOC (480 mg 4 weekly) vs extended interval (480 mg 8 weekly). Additional tumour cohorts are planned. Subject to satisfactory outcomes (progression-free survival) stage II will investigate up to 5 different treatment intervals. Secondary outcome measures include overall survival, quality-of-life, treatment-related toxicity, mean incremental pathway costs and quality-adjusted life-years per patient. REFINE is funded by the Jon Moulton Charity Trust and Medical Research Council, sponsored by University College London (UCL), and coordinated by the MRC CTU at UCL. Trial Registration ISRCTN79455488. NCT04913025 EUDRACT #: 2021-002060-47. CTA 31330/0008/001-0001; MREC approval: 21/LO/0593. REFINE Protocol version 4.0.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Nivolumabe/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Qualidade de Vida , Neoplasias Renais/tratamento farmacológico , Imunoterapia
3.
Support Care Cancer ; 31(1): 94, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36585510

RESUMO

PURPOSE: Shared decision making (SDM) among the oncology population is highly important due to complex screening and treatment decisions. SDM among patients with cancer, caregivers, and clinicians has gained more attention and importance, yet few articles have systematically examined SDM, specifically in the adult oncology population. This review aims to explore SDM within the oncology literature and help identify major gaps and concerns, with the goal to provide guidance in the development of clear SDM definitions and interventions. METHODS: We conducted a scoping review using the Arksey and O'Malley approach along with the PRISMA Extension for Scoping Reviews Checklist. A systematic search was conducted in four databases that included publications since 2016. RESULTS: Of the 364 initial articles, eleven publications met the inclusion criteria. We included articles that were original research, cancer related, and focused on shared decision making. Most studies were limited in defining SDM and operationalizing a model of SDM. There were several concerns revealed related to SDM: (1) racial inequality, (2) quality and preference of the patient, caregiver, and clinician communication is important, and (3) the use of a decision-making aid or tool provides value to the patient experience. CONCLUSION: Inconsistencies regarding the meaning and operationalization of SDM and inequality of the SDM process among patients from different racial/ethnic backgrounds impact the health and quality of care patients receive. Future studies should clearly and consistently define the meaning of SDM and develop decision aids that incorporate bidirectional, interactive communication between patients, caregivers, and clinicians that account for the diversity of racial, ethnic, and sociocultural backgrounds and preferences.


Assuntos
Tomada de Decisão Compartilhada , Neoplasias , Adulto , Humanos , Estados Unidos , Tomada de Decisões , Participação do Paciente , Oncologia , Neoplasias/terapia
4.
JMIR Cancer ; 8(3): e36879, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943791

RESUMO

BACKGROUND: Distressing cancer pain remains a serious symptom management issue for patients and family caregivers, particularly within home settings. Technology can support home-based cancer symptom management but must consider the experience of patients and family caregivers, as well as the broader environmental context. OBJECTIVE: This study aimed to test the feasibility and acceptability of a smart health sensing system-Behavioral and Environmental Sensing and Intervention for Cancer (BESI-C)-that was designed to support the monitoring and management of cancer pain in the home setting. METHODS: Dyads of patients with cancer and their primary family caregivers were recruited from an outpatient palliative care clinic at an academic medical center. BESI-C was deployed in each dyad home for approximately 2 weeks. Data were collected via environmental sensors to assess the home context (eg, light and temperature); Bluetooth beacons to help localize dyad positions; and smart watches worn by both patients and caregivers, equipped with heart rate monitors, accelerometers, and a custom app to deliver ecological momentary assessments (EMAs). EMAs enabled dyads to record and characterize pain events from both their own and their partners' perspectives. Sensor data streams were integrated to describe and explore the context of cancer pain events. Feasibility was assessed both technically and procedurally. Acceptability was assessed using postdeployment surveys and structured interviews with participants. RESULTS: Overall, 5 deployments (n=10 participants; 5 patient and family caregiver dyads) were completed, and 283 unique pain events were recorded. Using our "BESI-C Performance Scoring Instrument," the overall technical feasibility score for deployments was 86.4 out of 100. Procedural feasibility challenges included the rurality of dyads, smart watch battery life and EMA reliability, and the length of time required for deployment installation. Postdeployment acceptability Likert surveys (1=strongly disagree; 5=strongly agree) found that dyads disagreed that BESI-C was a burden (1.7 out of 5) or compromised their privacy (1.9 out of 5) and agreed that the system collected helpful information to better manage cancer pain (4.6 out of 5). Participants also expressed an interest in seeing their own individual data (4.4 out of 5) and strongly agreed that it is important that data collected by BESI-C are shared with their respective partners (4.8 out of 5) and health care providers (4.8 out of 5). Qualitative feedback from participants suggested that BESI-C positively improved patient-caregiver communication regarding pain management. Importantly, we demonstrated proof of concept that seriously ill patients with cancer and their caregivers will mark pain events in real time using a smart watch. CONCLUSIONS: It is feasible to deploy BESI-C, and dyads find the system acceptable. By leveraging human-centered design and the integration of heterogenous environmental, physiological, and behavioral data, the BESI-C system offers an innovative approach to monitor cancer pain, mitigate the escalation of pain and distress, and improve symptom management self-efficacy. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/16178.

5.
J Migr Health ; 6: 100116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677659

RESUMO

Introduction: Over 25,000 individuals are granted asylum status in the United States annually. Gender-based violence (GBV) has historically been supported as a claim for persecution to apply for asylum. In women, GBV is a known risk factor for sexually transmitted infections, poor mental health, and worse perinatal outcomes. Less is known about the links between GBV, asylum seekers, and gynecologic outcomes or care utilization. Reported rates of gynecologic care-seeking are low in asylum-seeking women and women with histories of GBV often experience barriers to care. We hypothesized that asylum-seeking women with a history of GBV at the Libertas Center, a comprehensive center for survivors of torture in New York City, would receive low rates of recommended gynecologic screening and infrequent gynecologic care. Materials and methods: This retrospective cross-sectional study included adult self-identified female patients who had completed intake at the Libertas Center from 2005-2020. In order to examine the relationship between GBV and gynecologic care use, patients were included if they had an electronic medical record (EMR) at Elmhurst Hospital, were female, 18 years of age and older, and had ever experienced GBV in their lifetime. EMRs were reviewed for medical and psychiatric diagnoses as well as routine components of gynecologic care and were linked to intake data from the Libertas Center characterizing patients' torture history. The primary outcome of this study was whether or not patients attended a gynecology visit. Demographic characteristics, medical histories, adequacy of gynecologic care, and gynecologic care-seeking behavior were compared between the gynecologic care group and the no gynecologic care group. Results: A total of 249 female patients were seen at the Libertas Center from December 2005 until January 2020 at the time of data collection. The prevalence of GBV in this population was 48%. Among women who suffered GBV, 81 received medical care at Elmhurst Hospital and 44 (54%) received gynecologic care. Nearly 50% of those patients who sought care at Elmhurst carried a diagnosis of post-traumatic stress disorder or depression. Women who received gynecologic care were significantly more likely than those who did not receive gynecologic care to have had an Emergency Room visit (68% vs. 41%), an obstetric visit (32% vs 3%), and/or have been seen by a social worker (46% vs 24%; all p < 0.05). Women who saw a gynecologist were significantly more likely to have completed four basic gynecologic care measures (Pap smear, gonorrhea/chlamydia screen, pelvic exam, and mammogram if applicable) compared to women who did not (77% vs 8%, p < 0.05). Conclusion: This study characterizes the gynecologic care utilization of female patients within a comprehensive care center for survivors of torture. We found a high lifetime rate of gender-based violence of 48% in this population. Adequate gynecologic care was uncommon among those who experienced GBV. However, gynecologic care was significantly more likely in patients receiving gynecologic specialty care, which frequently occurred after initial interaction with another provider (i.e. Emergency Department providers). These findings highlight the importance of trauma-informed care and establishing pathways to help asylum seeking and refugee women receive adequate gynecologic care. Further research is needed to explore specific barriers to gynecologic care in this population, how programs for asylum-seekers can integrate gynecologic care into existing structures for medical and mental healthcare, and how to increase awareness amongst providers on the prevalence of GBV and the gynecologic needs of these patients.

6.
BMC Palliat Care ; 20(1): 171, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34740339

RESUMO

BACKGROUND: One way to improve the delivery of oncology palliative care in low and middle-income countries (LMICs) is to leverage mobile technology to support healthcare providers in implementing pain management guidelines (PMG). However, PMG are often developed in higher-resourced settings and may not be appropriate for the resource and cultural context of LMICs. OBJECTIVES: This research represents a collaboration between the University of Virginia and the Nepalese Association of Palliative Care (NAPCare) to design a mobile health application ('app') to scale-up implementation of existing locally developed PMG. METHODS: We conducted a cross-sectional survey of clinicians within Nepal to inform design of the app. Questions focused on knowledge, beliefs, and confidence in managing cancer pain; barriers to cancer pain management; awareness and use of the NAPCare PMG; barriers to smart phone use and desired features of a mobile app. FINDINGS: Surveys were completed by 97 palliative care and/or oncology healthcare providers from four diverse cancer care institutions in Nepal. 49.5% (n = 48) had training in palliative care/cancer pain management and the majority (63.9%, n = 62) reported high confidence levels (scores of 8 or higher/10) in managing cancer pain. Highest ranked barriers to cancer pain management included those at the country/cultural level, such as nursing and medical school curricula lacking adequate content about palliative care and pain management, and patients who live in rural areas experiencing difficulty accessing healthcare services (overall mean = 6.36/10). Most nurses and physicians use an Android Smart Phone (82%, n = 74), had heard of the NAPCare PMG (96%, n = 88), and reported frequent use of apps to provide clinical care (mean = 6.38/10, n = 92). Key barriers to smart phone use differed by discipline, with nurses reporting greater concerns related to cost of data access (70%, n = 45) and being prohibited from using a mobile phone at work (61%; n = 39). CONCLUSIONS: Smart phone apps can help implement PMG and support healthcare providers in managing cancer pain in Nepal and similar settings. However, such tools must be designed to be culturally and contextually congruent and address perceived barriers to pain management and app use.


Assuntos
Telefone Celular , Aplicativos Móveis , Neoplasias , Estudos Transversais , Humanos , Neoplasias/complicações , Neoplasias/terapia , Nepal , Manejo da Dor
7.
Elife ; 102021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34212857

RESUMO

Mannose-sensitive hemagglutinin (MSHA) pili and flagellum are critical for the surface attachment of Vibrio cholerae, the first step of V. cholerae colonization on host surfaces. However, the cell landing mechanism remains largely unknown, particularly in viscoelastic environments such as the mucus layers of intestines. Here, combining the cysteine-substitution-based labeling method with single-cell tracking techniques, we quantitatively characterized the landing of V. cholerae by directly observing both pili and flagellum of cells in a viscoelastic non-Newtonian solution consisting of 2% Luria-Bertani and 1% methylcellulose (LB+MC). The results show that MSHA pili are evenly distributed along the cell length and can stick to surfaces at any point along the filament. With such properties, MSHA pili are observed to act as a brake and anchor during cell landing which includes three phases: running, lingering, and attaching. Importantly, loss of MSHA pili results in a more dramatic increase in mean path length in LB+MC than in 2% LB only or in 20% Ficoll solutions, indicating that the role of MSHA pili during cell landing is more apparent in viscoelastic non-Newtonian fluids than viscous Newtonian ones. Our work provides a detailed picture of the landing dynamics of V. cholerae under viscoelastic conditions, which can provide insights into ways to better control V. cholerae infections in a real mucus-like environment.


Assuntos
Proteínas de Fímbrias/fisiologia , Flagelos/fisiologia , Vibrio cholerae/fisiologia , Regulação Bacteriana da Expressão Gênica/fisiologia , Lectina de Ligação a Manose/fisiologia , Movimento , Análise de Célula Única , Substâncias Viscoelásticas
8.
Histopathology ; 79(4): 607-618, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33966296

RESUMO

AIMS: Phyllodes tumours (PT) are rare and distinct breast tumours, which span a morphological continuum. Classification into benign, borderline and malignant categories reflects their biology and clinical behaviour and is essential to guide management. This study aims to assess the diagnostic agreement of PT using the UK National Health Service Breast Screening Programme (NHSBSP) breast pathology external quality assurance (EQA) scheme data. METHODS AND RESULTS: Twenty-six PTs were identified in the EQA scheme, which were diagnosed by an average of 607 participants/circulation. Data on diagnostic categories were collected and representative slides were reviewed. The level of concordance between reporting pathologists was assessed. There were 14 benign, six borderline and six malignant PT. The overall rate of diagnosis agreement was 86% when analysed as benign lesions, borderline PT and malignant lesions, which decreased to 79% when diagnosed as PT (irrespective of grade) and to 63% when the diagnosis was further refined to PT categories (benign, borderline and malignant PTs). The highest agreement rate was observed in malignant PT (86%) and the lowest in borderline PT (42%). Malignant heterologous elements, stromal overgrowth and leaf-like architecture are features associated with higher concordance rates. Lower-priority features were stromal expansion, clefting and multinodularity. CONCLUSION: The concordance of PT diagnosis, as an entity, is high, but its classification into benign, borderline and malignant has variable agreement levels, with borderline tumours having the lowest concordance rate. More research to refine the diagnostic criteria for categorisation of PT is warranted to improve concordance between pathologists.


Assuntos
Neoplasias da Mama/diagnóstico , Tumor Filoide/diagnóstico , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Feminino , Humanos , Variações Dependentes do Observador , Patologistas , Tumor Filoide/classificação , Tumor Filoide/patologia
9.
Sci Adv ; 7(12)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33741591

RESUMO

Neuronal tau reduction confers resilience against ß-amyloid and tau-related neurotoxicity in vitro and in vivo. Here, we introduce a novel translational approach to lower expression of the tau gene MAPT at the transcriptional level using gene-silencing zinc finger protein transcription factors (ZFP-TFs). Following a single administration of adeno-associated virus (AAV), either locally into the hippocampus or intravenously to enable whole-brain transduction, we selectively reduced tau messenger RNA and protein by 50 to 80% out to 11 months, the longest time point studied. Sustained tau lowering was achieved without detectable off-target effects, overt histopathological changes, or molecular alterations. Tau reduction with AAV ZFP-TFs was able to rescue neuronal damage around amyloid plaques in a mouse model of Alzheimer's disease (APP/PS1 line). The highly specific, durable, and controlled knockdown of endogenous tau makes AAV-delivered ZFP-TFs a promising approach for the treatment of tau-related human brain diseases.


Assuntos
Doença de Alzheimer , Fatores de Transcrição , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Modelos Animais de Doenças , Camundongos , Placa Amiloide/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética , Proteínas tau/genética , Proteínas tau/metabolismo
10.
JMIR Form Res ; 4(8): e20836, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32712581

RESUMO

BACKGROUND: Inadequately managed pain is a serious problem for patients with cancer and those who care for them. Smart health systems can help with remote symptom monitoring and management, but they must be designed with meaningful end-user input. OBJECTIVE: This study aims to understand the experience of managing cancer pain at home from the perspective of both patients and family caregivers to inform design of the Behavioral and Environmental Sensing and Intervention for Cancer (BESI-C) smart health system. METHODS: This was a descriptive pilot study using a multimethod approach. Dyads of patients with cancer and difficult pain and their primary family caregivers were recruited from an outpatient oncology clinic. The participant interviews consisted of (1) open-ended questions to explore the overall experience of cancer pain at home, (2) ranking of variables on a Likert-type scale (0, no impact; 5, most impact) that may influence cancer pain at home, and (3) feedback regarding BESI-C system prototypes. Qualitative data were analyzed using a descriptive approach to identity patterns and key themes. Quantitative data were analyzed using SPSS; basic descriptive statistics and independent sample t tests were run. RESULTS: Our sample (n=22; 10 patient-caregiver dyads and 2 patients) uniformly described the experience of managing cancer pain at home as stressful and difficult. Key themes included (1) unpredictability of pain episodes; (2) impact of pain on daily life, especially the negative impact on sleep, activity, and social interactions; and (3) concerns regarding medications. Overall, taking pain medication was rated as the category with the highest impact on a patient's pain (=4.79), followed by the categories of wellness (=3.60; sleep quality and quantity, physical activity, mood and oral intake) and interaction (=2.69; busyness of home, social or interpersonal interactions, physical closeness or proximity to others, and emotional closeness and connection to others). The category related to environmental factors (temperature, humidity, noise, and light) was rated with the lowest overall impact (=2.51). Patients and family caregivers expressed receptivity to the concept of BESI-C and reported a preference for using a wearable sensor (smart watch) to capture data related to the abrupt onset of difficult cancer pain. CONCLUSIONS: Smart health systems to support cancer pain management should (1) account for the experience of both the patient and the caregiver, (2) prioritize passive monitoring of physiological and environmental variables to reduce burden, and (3) include functionality that can monitor and track medication intake and efficacy; wellness variables, such as sleep quality and quantity, physical activity, mood, and oral intake; and levels of social interaction and engagement. Systems must consider privacy and data sharing concerns and incorporate feasible strategies to capture and characterize rapid-onset symptoms.

11.
Acta Neuropathol ; 140(1): 7-24, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32236736

RESUMO

Phosphatase and tensin homolog (PTEN) regulates synaptic density in development; however, whether PTEN also regulates synapse loss in a neurodegenerative disorder such as frontotemporal lobar degeneration with Tau deposition (FTLD-Tau) has not been explored. Here, we found that pathological Tau promotes early activation of PTEN, which precedes apoptotic caspase-3 cleavage in the rTg4510 mouse model of FTLD-Tau. We further demonstrate increased synaptic and neuronal exposure of the apoptotic signal phosphatidylserine that tags neuronal structures for microglial uptake, thereby linking PTEN activation to synaptic and neuronal structure elimination. By applying pharmacological inhibition of PTEN's protein phosphatase activity, we observed that microglial uptake can be decreased in Tau transgenic mice. Finally, we reveal a dichotomous relationship between PTEN activation and age in FTLD-Tau patients and healthy controls. Together, our findings suggest that in tauopathy, PTEN has a role in the synaptotoxicity of pathological Tau and promotes microglial removal of affected neuronal structures.


Assuntos
Microglia/metabolismo , Neurônios/patologia , PTEN Fosfo-Hidrolase/metabolismo , Sinapses/patologia , Tauopatias/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Tauopatias/metabolismo
12.
mBio ; 11(1)2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32098815

RESUMO

What are bacteria doing during "reversible attachment," the period of transient surface attachment when they initially engage a surface, besides attaching themselves to the surface? Can an attaching cell help any other cell attach? If so, does it help all cells or employ a more selective strategy to help either nearby cells (spatial neighbors) or its progeny (temporal neighbors)? Using community tracking methods at the single-cell resolution, we suggest answers to these questions based on how reversible attachment progresses during surface sensing for Pseudomonas aeruginosa strains PAO1 and PA14. Although PAO1 and PA14 exhibit similar trends of surface cell population increase, they show unanticipated differences when cells are considered at the lineage level and interpreted using the quantitative framework of an exactly solvable stochastic model. Reversible attachment comprises two regimes of behavior, processive and nonprocessive, corresponding to whether cells of the lineage stay on the surface long enough to divide, or not, before detaching. Stark differences between PAO1 and PA14 in the processive regime of reversible attachment suggest the existence of two surface colonization strategies. PAO1 lineages commit quickly to a surface compared to PA14 lineages, with early c-di-GMP-mediated exopolysaccharide (EPS) production that can facilitate the attachment of neighbors. PA14 lineages modulate their motility via cyclic AMP (cAMP) and retain memory of the surface so that their progeny are primed for improved subsequent surface attachment. Based on the findings of previous studies, we propose that the differences between PAO1 and PA14 are potentially rooted in downstream differences between Wsp-based and Pil-Chp-based surface-sensing systems, respectively.IMPORTANCE The initial pivotal phase of bacterial biofilm formation known as reversible attachment, where cells undergo a period of transient surface attachment, is at once universal and poorly understood. What is more, although we know that reversible attachment culminates ultimately in irreversible attachment, it is not clear how reversible attachment progresses phenotypically, as bacterial surface-sensing circuits fundamentally alter cellular behavior. We analyze diverse observed bacterial behavior one family at a time (defined as a full lineage of cells related to one another by division) using a unifying stochastic model and show that our findings lead to insights on the time evolution of reversible attachment and the social cooperative dimension of surface attachment in PAO1 and PA14 strains.


Assuntos
Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia , Aderência Bacteriana , Fenômenos Fisiológicos Bacterianos , Proteínas de Bactérias , AMP Cíclico/metabolismo , Modelos Teóricos
13.
Mol Ther Methods Clin Dev ; 15: 320-332, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31788496

RESUMO

Adeno-associated virus (AAV) capsid libraries have generated improved transgene delivery vectors. We designed an AAV library construct, iTransduce, that combines a peptide library on the AAV9 capsid with a Cre cassette to enable sensitive detection of transgene expression. After only two selection rounds of the library delivered intravenously in transgenic mice carrying a Cre-inducible fluorescent protein, we flow sorted fluorescent cells from brain, and DNA sequencing revealed two dominant capsids. One of the capsids, termed AAV-F, mediated transgene expression in the brain cortex more than 65-fold (astrocytes) and 171-fold (neurons) higher than the parental AAV9. High transduction efficiency was sex-independent and sustained in two mouse strains (C57BL/6 and BALB/c), making it a highly useful capsid for CNS transduction of mice. Future work in large animal models will test the translation potential of AAV-F.

14.
Vet Anaesth Analg ; 46(3): 365-368, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30952441

RESUMO

OBJECTIVE: To determine agreement in oxygen consumption (V˙O2) values calculated using Sykes' formula V˙O2 = (FiO2 - Fe'O2) * V˙E (where Fi and Fe are the inspired and end-tidal fractional concentrations of O2, respectively, and V˙E is minute volume) with values derived using Brody's formula (V˙O2 = 10 kg3/4). It was hypothesized that the two methods would not yield statistically significant differences in calculated values. STUDY DESIGN: Prospective, clinical, pilot study. ANIMALS: A total of 22 client-owned dogs. METHODS: Dogs undergoing surgery were anaesthetized with either isoflurane or sevoflurane. The V˙E, FiO2 and Fe'O2 were measured during mechanical ventilation of the lungs (tidal volume 10 mL kg-1; respiratory rate: 8-12 breaths minute-1). Oesophageal temperature was maintained between 37.0 °C and 38.5 °C. Values for V˙O2 derived by Sykes' and Brody's methods were compared and agreement was determined using Bland-Altman analysis. RESULTS: Mean V˙O2 values were 4.67 ± 0.51 mL kg-1 minute-1 and 5.32 ± 1.69 mL kg-1 minute-1 calculated using Brody's formula and Sykes' equation, respectively. There was greater variability in the values obtained from Sykes' equation. The Bland-Altman plot revealed a proportional error with correlation but poor agreement between values. CONCLUSIONS AND CLINICAL RELEVANCE: Both methods yielded V˙O2 values of approximately 5 mL kg-1minute-1 with no statistically significant differences between the two methods.


Assuntos
Anestesia/veterinária , Cães , Modelos Biológicos , Consumo de Oxigênio , Oxigênio/análise , Anestésicos Inalatórios , Animais , Feminino , Isoflurano , Masculino , Projetos Piloto , Estudos Prospectivos , Respiração , Respiração Artificial/veterinária , Sevoflurano
15.
J Cell Biol ; 217(11): 3796-3808, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30171044

RESUMO

The nucleus is physically linked to the cytoskeleton, adhesions, and extracellular matrix-all of which sustain forces, but their relationships to DNA damage are obscure. We show that nuclear rupture with cytoplasmic mislocalization of multiple DNA repair factors correlates with high nuclear curvature imposed by an external probe or by cell attachment to either aligned collagen fibers or stiff matrix. Mislocalization is greatly enhanced by lamin A depletion, requires hours for nuclear reentry, and correlates with an increase in pan-nucleoplasmic foci of the DNA damage marker γH2AX. Excess DNA damage is rescued in ruptured nuclei by cooverexpression of multiple DNA repair factors as well as by soft matrix or inhibition of actomyosin tension. Increased contractility has the opposite effect, and stiff tumors with low lamin A indeed exhibit increased nuclear curvature, more frequent nuclear rupture, and excess DNA damage. Additional stresses likely play a role, but the data suggest high curvature promotes nuclear rupture, which compromises retention of DNA repair factors and favors sustained damage.


Assuntos
Núcleo Celular/metabolismo , Reparo do DNA , Histonas/metabolismo , Lamina Tipo A/metabolismo , Células A549 , Núcleo Celular/genética , Histonas/genética , Humanos , Lamina Tipo A/genética
16.
Proc Natl Acad Sci U S A ; 115(17): 4471-4476, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29559526

RESUMO

Using multigenerational, single-cell tracking we explore the earliest events of biofilm formation by Pseudomonas aeruginosa During initial stages of surface engagement (≤20 h), the surface cell population of this microbe comprises overwhelmingly cells that attach poorly (∼95% stay <30 s, well below the ∼1-h division time) with little increase in surface population. If we harvest cells previously exposed to a surface and direct them to a virgin surface, we find that these surface-exposed cells and their descendants attach strongly and then rapidly increase the surface cell population. This "adaptive," time-delayed adhesion requires determinants we showed previously are critical for surface sensing: type IV pili (TFP) and cAMP signaling via the Pil-Chp-TFP system. We show that these surface-adapted cells exhibit damped, coupled out-of-phase oscillations of intracellular cAMP levels and associated TFP activity that persist for multiple generations, whereas surface-naïve cells show uncorrelated cAMP and TFP activity. These correlated cAMP-TFP oscillations, which effectively impart intergenerational memory to cells in a lineage, can be understood in terms of a Turing stochastic model based on the Pil-Chp-TFP framework. Importantly, these cAMP-TFP oscillations create a state characterized by a suppression of TFP motility coordinated across entire lineages and lead to a drastic increase in the number of surface-associated cells with near-zero translational motion. The appearance of this surface-adapted state, which can serve to define the historical classification of "irreversibly attached" cells, correlates with family tree architectures that facilitate exponential increases in surface cell populations necessary for biofilm formation.


Assuntos
Aderência Bacteriana/fisiologia , Biofilmes/crescimento & desenvolvimento , AMP Cíclico/metabolismo , Fímbrias Bacterianas/fisiologia , Pseudomonas aeruginosa/fisiologia , Sistemas do Segundo Mensageiro/fisiologia
17.
EMBO J ; 37(7)2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29472250

RESUMO

The transition between soluble intrinsically disordered tau protein and aggregated tau in neurofibrillary tangles in Alzheimer's disease is unknown. Here, we propose that soluble tau species can undergo liquid-liquid phase separation (LLPS) under cellular conditions and that phase-separated tau droplets can serve as an intermediate toward tau aggregate formation. We demonstrate that phosphorylated or mutant aggregation prone recombinant tau undergoes LLPS, as does high molecular weight soluble phospho-tau isolated from human Alzheimer brain. Droplet-like tau can also be observed in neurons and other cells. We found that tau droplets become gel-like in minutes, and over days start to spontaneously form thioflavin-S-positive tau aggregates that are competent of seeding cellular tau aggregation. Since analogous LLPS observations have been made for FUS, hnRNPA1, and TDP43, which aggregate in the context of amyotrophic lateral sclerosis, we suggest that LLPS represents a biophysical process with a role in multiple different neurodegenerative diseases.


Assuntos
Doença de Alzheimer/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Encéfalo/metabolismo , Neurônios/metabolismo , Agregação Patológica de Proteínas/metabolismo , Proteínas tau/química , Proteínas tau/isolamento & purificação , Proteínas tau/metabolismo , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , Benzotiazóis/metabolismo , Fenômenos Biofísicos , Clonagem Molecular , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Feminino , Células HEK293 , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Humanos , Extração Líquido-Líquido , Camundongos , Camundongos Transgênicos , Peso Molecular , Neuroblastoma/metabolismo , Doenças Neurodegenerativas/metabolismo , Emaranhados Neurofibrilares/metabolismo , Fosforilação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de Proteína , Células Sf9
18.
Ir Vet J ; 71: 6, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29456834

RESUMO

BACKGROUND: The mortality rate of horses undergoing general anaesthesia is high when compared to humans or small animal patients. One of the most critical periods during equine anaesthesia is recovery, as the horse attempts to regain a standing position. This study was performed in a private equine practice in Belgium that uses a purpose-designed one-man (head and tail) rope recovery system to assist the horse during the standing process.The main purpose of the retrospective study was to report and analyse complications and the mortality rate in horses during recovery from anaesthesia using the described recovery system. Information retrieved from the medical records included patient signalment, anaesthetic protocol, duration of anaesthesia, ASA grade, type of surgery, recovery time and complications during recovery. Sedation was administered to all horses prior to recovery with the rope system. Complications were divided into major complications in which the horse was euthanized and minor complications where the horse survived. Major complications were further subdivided into those where the rope system did not contribute to the recovery complication (Group 1) and those where it was not possible to determine if the rope system was of any benefit (Group 2). RESULTS: Five thousand eight hundred fifty two horses recovered from general anaesthesia with rope assistance. Complications were identified in 30 (0.51%). Major complications occurred in 12 horses (0.20%) of which three (0.05%) were assigned to Group 1 and nine (0.15%) to Group 2. Three horses in Group 2 suffered musculoskeletal injuries (0.05%). Eighteen horses (0.31%) suffered minor complications, of which five (0.08%) were categorised as failures of the recovery system. CONCLUSIONS: This study reports the major and minor complication and mortality rate during recovery from anaesthesia using a specific type of rope recovery system. Mortality associated with the rope recovery system was low. During recovery from anaesthesia this rope system may reduce the risk of lethal complications, particularly major orthopaedic injuries.

19.
Proc Natl Acad Sci U S A ; 115(6): E1289-E1298, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29358399

RESUMO

Mixed pathology, with both Alzheimer's disease and vascular abnormalities, is the most common cause of clinical dementia in the elderly. While usually thought to be concurrent diseases, the fact that changes in cerebral blood flow are a prominent early and persistent alteration in Alzheimer's disease raises the possibility that vascular alterations and Alzheimer pathology are more directly linked. Here, we report that aged tau-overexpressing mice develop changes to blood vessels including abnormal, spiraling morphologies; reduced blood vessel diameters; and increased overall blood vessel density in cortex. Blood flow in these vessels was altered, with periods of obstructed flow rarely observed in normal capillaries. These changes were accompanied by cortical atrophy as well as increased expression of angiogenesis-related genes such as Vegfa, Serpine1, and Plau in CD31-positive endothelial cells. Interestingly, mice overexpressing nonmutant forms of tau in the absence of frank neurodegeneration also demonstrated similar changes. Furthermore, many of the genes we observe in mice are also altered in human RNA datasets from Alzheimer patients, particularly in brain regions classically associated with tau pathology such as the temporal lobe and limbic system regions. Together these data indicate that tau pathological changes in neurons can impact brain endothelial cell biology, altering the integrity of the brain's microvasculature.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Indutores da Angiogênese/metabolismo , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Neurônios/patologia , Proteínas tau/metabolismo , Envelhecimento , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Humanos , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Proteínas tau/genética
20.
Methods Cell Biol ; 141: 307-322, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28882310

RESUMO

The progressive spread of pathological brain lesions containing aggregated tau protein is a hallmark of Alzheimer's disease and other neurodegenerative diseases. In AD, this process follows a distinct pattern along neuronal connections from the entorhinal cortex to hippocampal areas and further on through the limbic system. In other tauopathies, the spread of tau appears less hierarchical throughout the brain, and also nonpathological tau is reported to cross-synaptic connections in the brain. To be able to study the process of cell-to-cell transport of tau and the associated neurotoxicity in the brain in vivo, adeno-associated virus-mediated expression of tau can be used to express different forms of tau in distinct brain areas in rodent models. As an example, we describe how the expression of FTD-mutant human tauP301L in the entorhinal cortex of wild-type mice can be used to study the propagation of tau to connected neurons and to determine pathological consequences such as tau hyperphosphorylation, misfolding, and gliosis. The approach described can easily be translated to study other aggregating and/or propagating proteins in the brain such as synuclein, Abeta, or SOD1.


Assuntos
Encéfalo/patologia , Dependovirus/genética , Modelos Animais de Doenças , Neurônios/patologia , Tauopatias/patologia , Proteínas tau/metabolismo , Animais , Encéfalo/metabolismo , Células Cultivadas , Humanos , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Fosforilação , Tauopatias/metabolismo , Proteínas tau/administração & dosagem , Proteínas tau/genética
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