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1.
Cell ; 184(10): 2733-2749.e16, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33861952

RESUMO

Significant evidence supports the view that dopamine shapes learning by encoding reward prediction errors. However, it is unknown whether striatal targets receive tailored dopamine dynamics based on regional functional specialization. Here, we report wave-like spatiotemporal activity patterns in dopamine axons and release across the dorsal striatum. These waves switch between activational motifs and organize dopamine transients into localized clusters within functionally related striatal subregions. Notably, wave trajectories were tailored to task demands, propagating from dorsomedial to dorsolateral striatum when rewards are contingent on animal behavior and in the opponent direction when rewards are independent of behavioral responses. We propose a computational architecture in which striatal dopamine waves are sculpted by inference about agency and provide a mechanism to direct credit assignment to specialized striatal subregions. Supporting model predictions, dorsomedial dopamine activity during reward-pursuit signaled the extent of instrumental control and interacted with reward waves to predict future behavioral adjustments.


Assuntos
Axônios/metabolismo , Comportamento Animal , Corpo Estriado/metabolismo , Dopamina/metabolismo , Recompensa , Animais , Feminino , Masculino , Camundongos , Camundongos Mutantes
2.
Nature ; 570(7759): 65-70, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31118513

RESUMO

The dopamine projection from ventral tegmental area (VTA) to nucleus accumbens (NAc) is critical for motivation to work for rewards and reward-driven learning. How dopamine supports both functions is unclear. Dopamine cell spiking can encode prediction errors, which are vital learning signals in computational theories of adaptive behaviour. By contrast, dopamine release ramps up as animals approach rewards, mirroring reward expectation. This mismatch might reflect differences in behavioural tasks, slower changes in dopamine cell spiking or spike-independent modulation of dopamine release. Here we compare spiking of identified VTA dopamine cells with NAc dopamine release in the same decision-making task. Cues that indicate an upcoming reward increased both spiking and release. However, NAc core dopamine release also covaried with dynamically evolving reward expectations, without corresponding changes in VTA dopamine cell spiking. Our results suggest a fundamental difference in how dopamine release is regulated to achieve distinct functions: broadcast burst signals promote learning, whereas local control drives motivation.


Assuntos
Dopamina/metabolismo , Aprendizagem/fisiologia , Motivação/fisiologia , Recompensa , Animais , Sinais (Psicologia) , Tomada de Decisões/fisiologia , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Masculino , Núcleo Accumbens/citologia , Núcleo Accumbens/fisiologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiologia , Ratos , Ratos Long-Evans , Fatores de Tempo , Área Tegmentar Ventral/citologia , Área Tegmentar Ventral/fisiologia
3.
Nature ; 571(7763): E3, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31217588

RESUMO

Change history: In this Article, an extraneous label appeared in Fig. 4b, and has been removed in the online version.

4.
Eur Heart J ; 44(35): 3311-3322, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37350487

RESUMO

Technological advancement and the COVID-19 pandemic have brought virtual learning and working into our daily lives. Extended realities (XR), an umbrella term for all the immersive technologies that merge virtual and physical experiences, will undoubtedly be an indispensable part of future clinical practice. The intuitive and three-dimensional nature of XR has great potential to benefit healthcare providers and empower patients and physicians. In the past decade, the implementation of XR into cardiovascular medicine has flourished such that it is now integrated into medical training, patient education, pre-procedural planning, intra-procedural visualization, and post-procedural care. This review article discussed how XR could provide innovative care and complement traditional practice, as well as addressing its limitations and considering its future perspectives.


Assuntos
COVID-19 , Realidade Virtual , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle
5.
Catheter Cardiovasc Interv ; 102(7): 1401-1405, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37694603

RESUMO

Valve-in-valve TAVI to treat failing surgical aortic valves (SAVs) is increasingly performed, and commissural alignment is a key technical aspect in such procedures. Surgeons optimize valve alignment, accounting for potential coronary eccentricity and achieving a patient-specific optimized commissural orientation, representing the ideal target for TAVI alignment. Therefore, here we present a dedicated stepwise valve-in-valve implantation technique using the ACURATE neo2. In a specific SAV postoverlap view, isolating one surgical post to the right of the screen representing the target for alignment, rotational orientation of the TAVI commissures, matching the SAV orientation, is achieved and verified before implantation. This technique has been tested in a patient-specific three-dimensionally-printed aortic root anatomy, attached to a pulsatile flow simulator, allowing for native-like simulation of coronary cannulations under fluoroscopy, and enabling detailed assessment with fluoroscopic as well as direct videographic visualization. Furthermore, the technique is exemplified by providing an educational clinical case example.


Assuntos
Estenose da Valva Aórtica , Bioprótese , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Resultado do Tratamento , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Desenho de Prótese
6.
Catheter Cardiovasc Interv ; 101(4): 798-805, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36841945

RESUMO

OBJECTIVES: The objective of this study is to investigate the use of cutting balloon (CB) inflated at high pressure compared with noncompliant balloon (NCB) for the treatment of calcified coronary lesions. BACKGROUND: No data are available regarding the safety and efficacy of CB inflated at high pressure in coronary artery calcifications. METHODS: Patients with calcified lesions (more than 100° of calcium demonstrated at baseline intravascular ultrasound) were randomized. Primary endpoint of the study was the final minimal stent area (MSA) and stent symmetry in the calcific segment. Secondary endpoints included rate of device failure and the 1-year rate of target lesion revascularization, target vessel revascularization, and major adverse cardiovascular events. RESULTS: From September 2019 to June 2021, a total of 100 patients were included and randomized; 13 patients were excluded for major protocol deviations. Lesions were complex (type B2/C n = 61 [71.2%]) with a mean arch of calcium of 266 ± 84°, a calcium length of 12 ± 6.6 mm. CB was inflated at comparable atmospheres when compared with NCB (18.3 ± 5 vs. 19 ± 4.5, p = 0.46). In the per-protocol population, the final MSA at the level of the calcium site was significantly higher in the CB group (8.1 ± 2 vs. 7.3 ± 2.1, p = 0.035) with a higher eccentricity index achieved in the CB group (0.84 ± 0.07 vs. 0.8 ± 0.08, p = 0.013). Three device failure occurred in the CB group. One-year follow-up outcomes were comparable. CONCLUSIONS: Treatment of calcified lesions with high-pressure CB has a good safety profile and is associated with a larger MSA and higher eccentricity of the stent at the level of the calcium site compared with NCB.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana , Humanos , Angiografia Coronária , Cálcio , Resultado do Tratamento , Doença da Artéria Coronariana/terapia , Stents
7.
J Headache Pain ; 24(1): 5, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647006

RESUMO

BACKGROUND: Many migraine patients do not respond adequately to conventional preventive treatments and are therefore described as treatment/medically resistant or difficult to treat cases. Calcitonin gene-related peptide monoclonal antibodies are a relatively novel molecular treatment for episodic and chronic migraine that have been shown to be effective in short duration clinical trials in approximately 40-50% of all chronic migraine patients. Patient Related Outcome Measures (PROM) or Quality of Life (QoL) questionnaires are used to help measure response to treatment in migraine. Although some open label extension studies have become available for erenumab, there is a lack of real-world data pertaining to quality of life in the medium to long-term for chronic and treatment resistant migraine patients. METHODS: A total of 177 treatment resistant CM patients were started on erenumab (70 mg or 140 mg subcutaneous injection every 4 weeks) in our three specialist Headache Clinics. Of these, 174 had their first injection between December 2018 and October 2019. All patients were evaluated with the following PROM: the Headache Impact Test- 6, Migraine Associated Disability Assessment test and Migraine-Specific QoL Questionnaire, before starting treatment with erenumab and at intervals of 3-12 months after starting treatment. The decision to continue treatment was based on subjective clinical improvement of at least 30% (as reported by the patient), supported with diaries and QoL questionnaires. We present here the QoL measurements for this group of 177 patients. Prior preventive migraine treatments included conventional oral prophylactic medications (such as topiramate, candesartan, propranolol, or amitriptyline), at least two cycles of PREEMPT protocol onabotulinumtoxin A or (in a small number of cases) neuromodulation with single pulse Transcranial Magnetic Stimulation. RESULTS: Of the 177 patients who started treatment with erenumab, 68/177 (38.4%) stopped during the first year, either due to lack of efficacy (no significant benefit or only minimal improvement) and/or possible side effects. 109/177 (61.6%) patients reported clinically significant improvement after 6-12 months and wished to stay on treatment. Twelve of these 109 patients subsequently stopped treatment in the period between 1 year and up to June 2021 (mainly due to a worsening of their migraine). Therefore, a total of 97/177 patients (54.8%) remained on treatment as of June 2021 (duration of treatment 17-30 months, median of 25 months). CONCLUSION: Approximately 55% of treatment resistant or difficult to treat CM patients who trialled erenumab in our clinics reported a subjective benefit and were still on treatment after 17-30 months.


Assuntos
Transtornos de Enxaqueca , Qualidade de Vida , Humanos , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/farmacologia , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/uso terapêutico , Método Duplo-Cego , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/prevenção & controle , Medidas de Resultados Relatados pelo Paciente , Cefaleia/tratamento farmacológico , Resultado do Tratamento
8.
Catheter Cardiovasc Interv ; 99(5): 1526-1528, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35094475

RESUMO

Robotic-assisted percutaneous interventions (R-PCI) is a revolutionary technology designed to improve operator safety and procedural precision. The second-generation CorPath GRX (Corindus) R-PCI platform allows operators to manipulate the guiding catheter using robotic joystick controls. We report a case where robotic guide catheter manipulation caused a dramatic left main stem dissection. We highlight important concepts learned following this complication.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Procedimentos Cirúrgicos Robóticos , Catéteres , Angiografia Coronária , Humanos , Doença Iatrogênica , Intervenção Coronária Percutânea/efeitos adversos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Stents , Resultado do Tratamento
9.
J Med Virol ; 93(8): 5177-5181, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33331650

RESUMO

Hepatitis E virus (HEV) infection is a significant public health issue in many developing countries, causing waterborne outbreaks as well as sporadic hepatitis. We report here an outbreak of HEV genotype 1f infection during April-May 2018 among people living at Halisohor, a low land in the southern part of Chottogram District of Bangladesh. A total of 933 patients were admitted to Combined Military Hospital (CMH), Chottogram, with symptoms of acute hepatitis. Among them, 550 patients were tested by ELISA for HEV-specific (IgM) and all were positive. Genotyping, sequencing, and phylogenetic analysis based on ORF2 region revealed that the outbreak was caused by genotype 1f and the strains were closely related to the previously reported HEV strains that caused the outbreak in Bangladesh in 2010. The current outbreak was most likely linked with water supply as fecal contamination in water was evident and could be prevented by ensuring access to safe drinking water.


Assuntos
Surtos de Doenças , Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Hepatite E/virologia , Bangladesh/epidemiologia , Feminino , Genótipo , Anticorpos Anti-Hepatite/sangue , Hepatite E/diagnóstico , Vírus da Hepatite E/classificação , Vírus da Hepatite E/imunologia , Vírus da Hepatite E/isolamento & purificação , Hospitalização , Humanos , Imunoglobulina M/sangue , Masculino , Filogenia
10.
Catheter Cardiovasc Interv ; 98(3): E365-E369, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33851771

RESUMO

AIM: Coronary sinus (CS) reducer implantation is associated with symptomatic relief of patients with refractory angina. However, 15% to 30% of the patients do not respond to this treatment. Aim if this study was to evaluate the effect of CS size in the effectiveness of the device. METHODS: Prior to device implantation and at 4-month resting ventricular function was assessed by stress cardiac magnetic resonance. Ischemia was assessed by the myocardial perfusion reserve index (MPRI). RESULTS: Fifteen patients (66 ± 10 years) underwent successful CS Reducer implantation, with improvements in angina class and exercise tolerance. Patients with a smaller CS size (<5.8 mm) presented a significantly higher percentage increase in MPRI (63 ± 51 vs 9 ± 30%, P = .03) and a higher reduction in left ventricle end-diastolic volumes. CONCLUSIONS: Greater benefits, in terms of ischemia improvement, after CS Reducer implantation were seen in patients with smaller CS sizes, suggesting a potential mechanism underlying the observed rates of reducer non-responsiveness.


Assuntos
Seio Coronário , Angina Pectoris , Seio Coronário/diagnóstico por imagem , Tolerância ao Exercício , Humanos , Isquemia , Resultado do Tratamento
11.
Catheter Cardiovasc Interv ; 98(3): 595-604, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33586278

RESUMO

BACKGROUND: Valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) is an emerging alternative to re-do surgery. However, the challenge of coronary access (CA) following ViV-TAVR is a potential limitation as TAVR expands to younger lower-risk populations. OBJECTIVES: Using post-implantation computed tomography (CT) scans to evaluate the geometrical relationship between coronary ostia and valve frame in patients undergoing ViV-TAVR with the ACURATE neo valve. METHODS: Post-implant CT scans of 18 out of 20 consecutive patients treated with the ACURATE neo valve were analyzed. Coronary ostia location in relation to the highest plane (HP) (highest point of the ACURATE neo or surgical valve) was determined. Ostia located below the highest plan were further subclassified according to the gap available between the transcatheter heart valve frame and ostium (transcatheter-to-coronary [TTC] distance). The impact implantation depth has on these geometrical relationships was evaluated. RESULTS: A total of 21 out of 36 coronary ostia (58%) were located below the level of the HP with the left coronary artery (36%) more likely to be affected than the right (22%). Further sub-classification of these ostia revealed a large (>6 mm), moderate (4-6 mm), and small (<4 mm) TTC distance in 57% (12/21), 38% (8/21), and in 6% (1/18) of cases, respectively. At an implantation depth <4 mm compared to >4 mm, all ostia were located below the HP with no difference in post-procedural mean gradients (14.5 mmHg ± 4.7 vs. 12.6 mmHg ± 5.8; p = .5, 95%CI 3.8-7.5). CONCLUSIONS: CA following ACURATE neo implantation for ViV-TAVR could potentially be challenging in a significant proportion of patients and specific consideration should be given to the implantation depth.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Humanos , Desenho de Prótese , Tomografia , Tomografia Computadorizada por Raios X , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
12.
Support Care Cancer ; 29(2): 925-943, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32535678

RESUMO

PURPOSE: Bone-modifying agents (BMAs) for bone metastases are commonly prescribed for many years even though randomized clinical trials are only 1-2 years in duration. A systematic review on the risk-benefit of BMA use for > 2 years in breast cancer or castrate-resistant prostate cancer was conducted. METHODS: MEDLINE, Embase, and Cochrane databases were searched (1970-February 2019) for randomized and observational studies, and case series reporting on BMA efficacy (skeletal-related events and quality of life) and toxicity (osteonecrosis of the jaw, renal impairment, hypocalcemia, and atypical femoral fractures) beyond 2 years. RESULTS: Of 2107 citations, 64 studies were identified. Three prospective and 9 retrospective studies were eligible. Data beyond 2 years was limited to subgroup analyses in all studies. Only one study (n = 181) reported skeletal-related event rates based on bisphosphonate exposure, with decreased rates from 27.6% (0-24 months) to 15.5% (> 24 months). None reported on quality of life. All 12 studies (denosumab (n = 948), zoledronate (n = 1036), pamidronate (n = 163), pamidronate-zoledronate (n = 522), ibandronate (n = 118)) reported ≥ 1 toxicity outcome. Seven bisphosphonate studies (n = 1077) and one denosumab study (n = 948) reported on osteonecrosis of the jaw. Across three studies (n = 1236), osteonecrosis of the jaw incidence ranged from 1 to 4% in the first 2 years to 3.8-18% after 2 years. Clinically significant hypocalcemia ranged from 1 to 2%. Severe renal function decline was ≤ 3%. Atypical femoral fractures were rare. CONCLUSIONS: Evidence informing the use of BMA beyond 2 years is heterogeneous and based on retrospective analysis. Prospective randomized studies with greater emphasis on quality of life are needed. PROSPERO REGISTRATION NUMBER: CRD42019126813.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Difosfonatos/uso terapêutico , Feminino , Humanos , Masculino , Estudos Observacionais como Assunto , Estudos Prospectivos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
13.
Curr Cardiol Rep ; 23(10): 137, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34410511

RESUMO

PURPOSE OF THE REVIEW: Annular-based strategies for treating tricuspid valve (TV) regurgitation do not always have satisfactory long-term outcomes. Management of failed TV annuloplasty can be challenging and requires a dedicated heart team approach. This review explores the treatment options available for failed TV annuloplasty. RECENT FINDINGS: Recent developments and novel percutaneous treatment options have emerged as promising alternatives for patients with failed TV annuloplasty. Leaflet-based interventions, valve-in-valve procedures, transcatheter tricuspid valves and new-generation trans-caval valves are all feasible options, which can assure good results whilst minimizing risks for the patient. Failure of tricuspid annuloplasty is not uncommon amongst patients treated with either a tricuspid ring or suture-based device. The complex anatomy, physiology and clinical risk profile should be carefully evaluated on an individual patient-by-patient basis in order to select the most appropriate clinical and percutaneous treatment strategy. Different transcatheter tricuspid valve repair or replacement techniques may provide an attractive alternative treatment option for managing this challenging patient cohort.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Tricúspide , Valva Aórtica , Humanos , Valva Mitral/cirurgia , Recidiva , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia
14.
Entropy (Basel) ; 23(11)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34828185

RESUMO

Multi-Inputs-Multi-Outputs (MIMO) systems are recognized mainly in industrial applications with both input and state couplings, and uncertainties. The essential principle to deal with such difficulties is to eliminate the input couplings, then estimate the remaining issues in real-time, followed by an elimination process from the input channels. These difficulties are resolved in this research paper, where a decentralized control scheme is suggested using an Improved Active Disturbance Rejection Control (IADRC) configuration. A theoretical analysis using a state-space eigenvalue test followed by numerical simulations on a general uncertain nonlinear highly coupled MIMO system validated the effectiveness of the proposed control scheme in controlling such MIMO systems. Time-domain comparisons with the Conventional Active Disturbance Rejection Control (CADRC)-based decentralizing control scheme are also included.

15.
Malays J Pathol ; 43(2): 303-310, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34448794

RESUMO

Death-in-custody refers to the occurrence of death, while a person is under the custody of any enforcement agency. Their incidence often creates overwhelming public and media attention. Currently, there is no standardised definition of 'death-in-custody' in Malaysia and internationally. A crosssectional descriptive study was performed in the Department of Forensic Medicine Hospital Tuanku Ja'afar Seremban (HTJS) for a period of 24 months. Information on all custodial deaths registered at HTJS from January 2001 till December 2015 was selected from the in-house hospital death registration system. The definition of 'death-in-custody' used was guided by the recommendation by the 'Australian Royal Commission into Aboriginal Deaths in Custody' 1991 with few adjustments. Four custodial settings of interest (the police, prison, immigration depot for the illegal immigrant, and army custody) were studied. A total of 172 deaths-in-custody were collected, in which the majority of cases were natural deaths (84.88%), predominantly infective in nature (65.07%). Less than 1/6th of cases were unnatural deaths with more than 80% died from legal intervention. All custodial deaths were dominated by males (96.51%) with a mean and median age of 37 years. In terms of nationality, 52.91% of the deaths involved Malaysian citizens in which the 'Malay/Bumi' race outnumbered the other two main races. The most documented custodial deaths occurred in prison (44.19%) followed by immigration depots (38.37%) and police lock-ups (17.44%). This study provides a general overview of the pattern including the causes and the demographic profile involving death in custody in the Seremban district registered at HTJS.


Assuntos
Medicina Legal , Adulto , Austrália , Causas de Morte , Feminino , Hospitais , Humanos , Masculino , Polícia , Prisioneiros
16.
J Immunol ; 200(8): 2915-2926, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29549178

RESUMO

Circulating conventional memory CD8+ T cells (i.e., the CD8+ effector memory T [TEM] cell and CD8+ central memory T [TCM] cell subsets) and the noncirculating CD8+ tissue-resident memory T (TRM) cell subset play a critical role in mucosal immunity. Mucosal chemokines, including the recently discovered CXCL17, are also important in mucosal immunity because they are homeostatically expressed in mucosal tissues. However, whether the CXCL17 chemokine contributes to the mobilization of memory CD8+ T cell subsets to access infected mucosal tissues remains to be elucidated. In this study, we report that after intravaginal HSV type 1 infection of B6 mice, we detected high expression levels of CXCL17 and increased numbers of CD44highCD62LlowCD8+ TEM and CD103highCD8+ TRM cells expressing CXCR8, the cognate receptor of CXCL17, in the vaginal mucosa (VM) of mice with reduced genital herpes infection and disease. In contrast to wild-type B6 mice, the CXCL17-/- mice developed 1) fewer CXCR8+CD8+ TEM and TRM cells associated with more virus replication in the VM and more latency established in dorsal root ganglia, and 2) reduced numbers and frequencies of functional CD8+ T cells in the VM. These findings suggest that the CXCL17/CXCR8 chemokine pathway plays a crucial role in mucosal vaginal immunity by promoting the mobilization of functional protective CD8+ TEM and CD8+ TRM cells, within this site of acute and recurrent herpes infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Quimiocinas CXC/imunologia , Herpes Genital/imunologia , Imunidade nas Mucosas/imunologia , Vagina/imunologia , Animais , Quimiotaxia de Leucócito/imunologia , Feminino , Memória Imunológica/imunologia , Camundongos , Subpopulações de Linfócitos T/imunologia
17.
Eur J Immunol ; 48(5): 803-814, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29315518

RESUMO

Expansion and death of effector CD8 T cells are regulated to limit immunopathology and cells that escape contraction go on to generate immunological memory. CD44, a receptor for the extracellular matrix component hyaluronan, is a marker of activated and memory T cells. Here, we show with a murine model that the increase in CD44 expression and hyaluronan binding induced upon CD8 T cell activation was proportional to the strength of TCR engagement, thereby identifying the most strongly activated T cells. When CD44-/- and CD44+/+ OT-I CD8 T cells were adoptively transferred into mice challenged with Listeria-OVA, there was a slight increase in the percentage of CD44+/+ cells at the effector site. However, CD44+/+ cells were out-competed by CD44-/- cells after the contraction phase in the lymphoid tissues, and the CD44-/- cells preferentially formed more memory cells. The hyaluronan-binding CD44+/+ CD8 effector T cells showed increased pAkt expression, higher glucose uptake, and were more susceptible to cell death during the contraction phase compared to non-binding CD44+/+ and CD44-/- OT-I CD8 T cells, suggesting that CD44 and its engagement with hyaluronan skews CD8 T cells toward a terminal effector differentiation state that reduces their ability to form memory cells.


Assuntos
Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Memória Imunológica/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/transplante , Diferenciação Celular/imunologia , Receptores de Hialuronatos/genética , Listeria monocytogenes/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia
18.
J Virol ; 92(16)2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29899087

RESUMO

Herpes simplex virus 1 (HSV-1) is a prevalent human pathogen that infects the cornea, causing potentially blinding herpetic disease. A clinical herpes vaccine is still lacking. In the present study, a novel prime/pull vaccine was tested in a human leukocyte antigen (HLA) transgenic rabbit model of ocular herpes (HLA Tg rabbits). Three peptide epitopes were selected, from the HSV-1 membrane glycoprotein C (UL44400-408), the DNA replication binding helicase (UL9196-204), and the tegument protein (UL25572-580), all preferentially recognized by CD8+ T cells from "naturally protected" HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who never had recurrent corneal herpetic disease). HLA Tg rabbits were immunized with a mixture of these three ASYMP CD8+ T cell peptide epitopes (UL44400-408, UL9196-204, and UL25572-580), which were delivered subcutaneously with CpG2007 adjuvant (prime). Fifteen days later, half of the rabbits received a topical ocular treatment with a recombinant neurotropic adeno-associated virus type 8 (AAV8) vector expressing the T cell-attracting CXCL10 chemokine (pull). The frequency and function of HSV-specific CD8+ T cells induced by the prime/pull vaccine were assessed in the peripheral blood, cornea, and trigeminal ganglion (TG). Compared to the cells generated in response to peptide immunization alone, the peptide/CXCL10 prime/pull vaccine generated frequent polyfunctional gamma interferon-positive (IFN-γ+) CD107+ CD8+ T cells that infiltrated both the cornea and TG. CD8+ T cell mobilization into the cornea and TG of prime/pull-vaccinated rabbits was associated with a significant reduction in corneal herpesvirus infection and disease following an ocular HSV-1 (strain McKrae) challenge. These findings draw attention to the novel prime/pull vaccine strategy for mobilizing antiviral CD8+ T cells into tissues to protect against herpesvirus infection and disease.IMPORTANCE There is an urgent need for a vaccine against widespread herpes simplex virus infections. The present study demonstrates that immunization of HLA transgenic rabbits with a peptide/CXCL10 prime/pull vaccine triggered mobilization of HSV-specific CD8+ T cells locally into the cornea and TG, the sites of acute and latent herpesvirus infections, respectively. Mobilization of antiviral CD8+ T cells into the cornea and TG of rabbits that received the prime/pull vaccine was associated with protection against ocular herpesvirus infection and disease following an ocular HSV-1 challenge. These results highlight the importance of the prime/pull vaccine strategy to bolster the number and function of protective CD8+ T cells within infected tissues.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Quimiocina CXCL10/metabolismo , Córnea/imunologia , Vacinas contra o Vírus do Herpes Simples/imunologia , Ceratite Herpética/prevenção & controle , Subpopulações de Linfócitos T/imunologia , Gânglio Trigeminal/imunologia , Animais , Animais Geneticamente Modificados , Quimiocina CXCL10/administração & dosagem , Modelos Animais de Doenças , Epitopos/imunologia , Antígenos HLA/genética , Antígenos HLA/metabolismo , Vacinas contra o Vírus do Herpes Simples/administração & dosagem , Humanos , Interferon gama/análise , Ceratite Herpética/patologia , Ceratite Herpética/virologia , Proteína 1 de Membrana Associada ao Lisossomo/análise , Coelhos , Simplexvirus/imunologia , Simplexvirus/isolamento & purificação , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Carga Viral
19.
BMC Med Genet ; 20(1): 193, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822280

RESUMO

BACKGROUND: The deficiency of vitamin D receptor (VDR) or its ligand, vitamin D3, is linked to the development of renal diseases. The TaqI (rs731236) and ApaI (rs7975232) polymorphisms of VDR gene are widely studied for their association with renal disease risk. However, studies have largely been ambiguous. METHODS: Meta-analysis was carried out to clarify the association of TaqI (2777 cases and 3522 controls) and ApaI (2440 cases and 3279 controls) polymorphisms with nephrolithiasis (NL), diabetic nephropathy (DN) and end stage renal disease (ESRD). RESULTS: The VDR TaqI C-allele under allele contrast was significantly associated with ESRD in both fixed effect and random effect models, and ApaI C-allele with ESRD only under fixed effect model. Cochrane Q-test showed no evidence of heterogeneity for TaqI polymorphism and a significant heterogeneity for Apa I polymorphism. No publication bias was observed for both the polymorphisms. CONCLUSIONS: The present meta-analysis identifies TaqI and ApaI polymorphisms of VDR gene as risk factors for renal diseases.


Assuntos
Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Nefropatias Diabéticas/genética , Falência Renal Crônica/genética , Nefrolitíase/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Estudos de Casos e Controles , Humanos , Receptores de Calcitriol/metabolismo
20.
J Immunol ; 199(1): 186-203, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28539429

RESUMO

HSV type 1 (HSV-1) is a prevalent human pathogen that infects >3.72 billion individuals worldwide and can cause potentially blinding recurrent corneal herpetic disease. HSV-1 establishes latency within sensory neurons of trigeminal ganglia (TG), and TG-resident CD8+ T cells play a critical role in preventing its reactivation. The repertoire, phenotype, and function of protective CD8+ T cells are unknown. Bolstering the apparent feeble numbers of CD8+ T cells in TG remains a challenge for immunotherapeutic strategies. In this study, a comprehensive panel of 467 HLA-A*0201-restricted CD8+ T cell epitopes was predicted from the entire HSV-1 genome. CD8+ T cell responses to these genome-wide epitopes were compared in HSV-1-seropositive symptomatic individuals (with a history of numerous episodes of recurrent herpetic disease) and asymptomatic (ASYMP) individuals (who are infected but never experienced any recurrent herpetic disease). Frequent polyfunctional HSV-specific IFN-γ+CD107a/b+CD44highCD62LlowCD8+ effector memory T cells were detected in ASYMP individuals and were primarily directed against three "ASYMP" epitopes. In contrast, symptomatic individuals have more monofunctional CD44highCD62LhighCD8+ central memory T cells. Furthermore, therapeutic immunization with an innovative prime/pull vaccine, based on priming with multiple ASYMP epitopes (prime) and neurotropic TG delivery of the T cell-attracting chemokine CXCL10 (pull), boosted the number and function of CD44highCD62LlowCD8+ effector memory T cells and CD103highCD8+ tissue-resident T cells in TG of latently infected HLA-A*0201-transgenic mice and reduced recurrent ocular herpes following UV-B-induced reactivation. These findings have profound implications in the development of T cell-based immunotherapeutic strategies to treat blinding recurrent herpes infection and disease.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Herpesvirus Humano 1/imunologia , Memória Imunológica , Ceratite Herpética/imunologia , Gânglio Trigeminal/imunologia , Gânglio Trigeminal/virologia , Latência Viral , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/fisiologia , Quimiocina CXCL10/imunologia , Epitopos/química , Epitopos/imunologia , Epitopos/isolamento & purificação , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Imunização , Ceratite Herpética/terapia , Ceratite Herpética/virologia , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Recidiva , Gânglio Trigeminal/citologia , Adulto Jovem
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