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1.
Heart Surg Forum ; 22(5): E372-E374, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31596714

RESUMO

As a bridge to heart transplantation or destination treatment, implantation of the Heartmate 3 (HM3) left ventricular assist device is a viable option for patients with end-stage congestive heart failure. The recent Momentum 3 trial has shown favorable outcomes compared with Heartmate 2. We report the first case of aortic root thrombus occurring early after HM3 implantation as a bridge to heart transplantation. Our case suggests that bridging with an Impella 5.0 preceding HM3 implantation could potentially predispose patients to aortic root thrombus after HM3 implantation, due to Impella-related injury to the aortic valve and aortic root stasis after durable LVAD support.


Assuntos
Aorta/lesões , Valva Aórtica/lesões , Doenças das Valvas Cardíacas/etiologia , Coração Auxiliar/efeitos adversos , Complicações Pós-Operatórias/etiologia , Trombose/etiologia , Aorta/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Trombose/diagnóstico por imagem , Trombose/cirurgia
2.
Transpl Infect Dis ; 19(5)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28695649

RESUMO

In endemic regions, coccidioidomycosis causes substantial morbidity and mortality for patients receiving solid organ transplants. We aimed to demonstrate the effect of antifungal coccidioidal prophylaxis in heart transplant (HT) recipients. We retrospectively reviewed the electronic health records of all patients who received HTs between October 19, 2005, and December 13, 2014. We collected information regarding antifungal regimens and determined whether patients subsequently developed infections. Our 174-person cohort all received antifungal prophylaxis for at least 6 months (mean follow-up, 53.8 months). One proven and one probable coccidioidal infection (each, 0.6%) occurred during the study period. The incidence of coccidioidomycosis was 0.6% at 1 year and 2.3% at 5 years. No cases of proven coccidioidomycosis occurred within 2 years after transplantation. No patients developed disseminated disease, and no sentinel events were attributed to coccidioidomycosis. Both fluconazole and voriconazole were well tolerated. In the absence of intolerance or contraindication, we suggest continuing a universal antifungal prophylactic regimen with fluconazole for at least 6-12 months in HT recipients residing in a coccidioidomycosis-endemic area.


Assuntos
Antifúngicos/farmacologia , Coccidioidomicose/epidemiologia , Coccidioidomicose/prevenção & controle , Doenças Endêmicas/prevenção & controle , Transplante de Coração/efeitos adversos , Antifúngicos/administração & dosagem , Arizona/epidemiologia , Humanos , Estudos Retrospectivos
3.
Ann Hepatol ; 15(1): 33-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26626638

RESUMO

BACKGROUND: Acute hepatitis E virus (HEV) infection in solid organ transplant recipients is rare, but can cause severe hepatic and extrahepatic complications. We sought to identify the pretransplant prevalence of HEV infection in heart and kidney candidates and any associated risk factors for infection. MATERIAL AND METHODS: Stored frozen serum from patients undergoing evaluation for transplant was tested for HEV immunoglobulin G (IgG) antibodies and HEV RNA. All patients were seen at Mayo Clinic Hospital, Phoenix, Arizona, with 333 patients evaluated for heart (n = 132) or kidney (n = 201) transplant. HEV IgG antibodies (anti-HEV IgG) were measured by enzyme-linked immunosorbent assay, and HEV RNA by a noncommercial nucleic acid amplification assay. RESULTS: The prevalence of anti-HEV IgG was 11.4% (15/132) for heart transplant candidates and 8.5% (17/201) for kidney transplant candidates, with an overall seroprevalence of 9.6% (32/333). None of the patients tested positive for HEV RNA in the serum. On multivariable analysis, age older than 60 years was associated with HEV infection (adjusted odds ratio, 3.34; 95% CI, 1.54-7.24; P = 0.002). CONCLUSIONS: We conclude that there was no evidence of acute HEV infection in this pretransplant population and that older age seems to be associated with positive anti-HEV IgG.


Assuntos
Transplante de Coração , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Hepatite E/virologia , Transplante de Rim , RNA Viral/sangue , Adulto , Fatores Etários , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite E/sangue , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Análise Multivariada , Técnicas de Amplificação de Ácido Nucleico , Razão de Chances , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Sudoeste dos Estados Unidos/epidemiologia , Adulto Jovem
4.
Sci Rep ; 14(1): 21841, 2024 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-39294257

RESUMO

To fertilize eggs, sperm must pass through narrow, complex channels filled with viscoelastic fluids in the female reproductive tract. While it is known that the topography of the surfaces plays a role in guiding sperm movement, sperm have been thought of as swimmers, i.e., their motility comes solely from sperm interaction with the surrounding fluid, and therefore, the surfaces have no direct role in the motility mechanism itself. Here, we examined the role of solid surfaces in the movement of sperm in a highly viscoelastic medium. By visualizing the flagellum interaction with surfaces in a microfluidic device, we found that the flagellum stays close to the surface while the kinetic friction between the flagellum and the surface is in the direction of sperm movement, providing thrust. Additionally, the flow field generated by sperm suggests slippage between the viscoelastic fluid and the solid surface, deviating from the no-slip boundary typically used in standard fluid dynamics models. These observations point to hybrid motility mechanisms in sperm involving direct flagellum-surface interaction in addition to flagellum pushing the fluid. This finding signifies an evolutionary strategy of mammalian sperm crucial for their efficient migration through narrow, mucus-filled passages of the female reproductive tract.


Assuntos
Motilidade dos Espermatozoides , Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Masculino , Animais , Espermatozoides/fisiologia , Viscosidade , Elasticidade , Cauda do Espermatozoide/fisiologia , Feminino
5.
J Cardiovasc Dev Dis ; 11(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535118

RESUMO

Cardiac allograft vasculopathy (CAV) is a distinct form of coronary artery disease that represents a major cause of death beyond the first year after heart transplantation. The pathophysiology of CAV is still not completely elucidated; it involves progressive circumferential wall thickening of both the epicardial and intramyocardial coronary arteries. Coronary angiography is still considered the gold-standard test for the diagnosis of CAV, and intravascular ultrasound (IVUS) can detect early intimal thickening with improved sensitivity. However, these tests are invasive and are unable to visualize and evaluate coronary microcirculation. Increasing evidence for non-invasive surveillance techniques assessing both epicardial and microvascular components of CAV may help improve early detection. These include computed tomography coronary angiography (CTCA), single-photon emission computed tomography (SPECT), positron emission tomography (PET), and vasodilator stress myocardial contrast echocardiography perfusion imaging. This review summarizes the current state of diagnostic modalities and their utility and prognostic value for CAV and also evaluates emerging tools that may improve the early detection of this complex disease.

6.
J Pers Med ; 14(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276220

RESUMO

Current management of patients with congenital heart disease has increased their survival into adulthood. This is accompanied by potential cardiac complications, including pulmonary hypertension associated with congenital heart disease (PAH-CHD). PAH-CHD constitutes a challenging subgroup of pulmonary hypertension and requires expert management to improve quality of life and prognosis. Novel agents have shown a significant improvement in morbidity and mortality in patients with pulmonary arterial hypertension. However, the long-term effects of these medications on PAH-CHD patients remain somewhat uncertain, necessitating treatment plans largely founded on the clinical experience of the healthcare providers. The aim of this review is to summarize the current evidence and future perspectives regarding treatment strategies for PAH-CHD to help better guide management of this complex disease.

7.
J Clin Med ; 11(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35054016

RESUMO

Mammalian target of rapamycin (mTOR) inhibitors have been shown to reduce proliferation of lymphoid cells; thus, their use for immunosuppression after heart transplantation (HT) may reduce post-transplant lymphoproliferative disorder (PTLD) risk. This study sought to investigate whether the sirolimus (SRL)-based immunosuppression regimen is associated with a decreased risk of PTLD compared with the calcineurin inhibitor (CNI)-based regimen in HT recipients. We retrospectively analyzed 590 patients who received HTs at two large institutions between 1 June 1988 and 31 December 2014. Cox proportional-hazard modeling was used to examine the association between type of primary immunosuppression and PTLD after adjustment for potential confounders, including Epstein-Barr virus (EBV) status, type of induction therapy, and rejection. Conversion from CNI to SRL as primary immunosuppression occurred in 249 patients (42.2%). During a median follow-up of 6.3 years, 30 patients developed PTLD (5.1%). In a univariate analysis, EBV mismatch was strongly associated with increased risk of PTLD (HR 10.0, 95% CI: 3.8-26.6; p < 0.001), and conversion to SRL was found to be protective against development of PTLD (HR 0.19, 95% CI: 0.04-0.80; p = 0.02). In a multivariable model and after adjusting for EBV mismatch, conversion to SRL remained protective against risk of PTLD compared with continued CNI use (HR 0.12, 95% CI: 0.03-0.55; p = 0.006). In conclusion, SRL-based immunosuppression is associated with lower incidence of PTLD after HT. These findings provide evidence of a benefit from conversion to SRL as maintenance therapy for mitigating the risk of PTLD, particularly among patients at high PTLD risk.

8.
Elife ; 102021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236312

RESUMO

Identifying neural substrates of behavior requires defining actions in terms that map onto brain activity. Brain and muscle activity naturally correlate via the output of motor neurons, but apart from simple movements it has been difficult to define behavior in terms of muscle contractions. By mapping the musculature of the pupal fruit fly and comprehensively imaging muscle activation at single-cell resolution, we here describe a multiphasic behavioral sequence in Drosophila. Our characterization identifies a previously undescribed behavioral phase and permits extraction of major movements by a convolutional neural network. We deconstruct movements into a syllabary of co-active muscles and identify specific syllables that are sensitive to neuromodulatory manipulations. We find that muscle activity shows considerable variability, with sequential increases in stereotypy dependent upon neuromodulation. Our work provides a platform for studying whole-animal behavior, quantifying its variability across multiple spatiotemporal scales, and analyzing its neuromodulatory regulation at cellular resolution.


How do we find out how the brain works? One way is to use imaging techniques to visualise an animal's brain in action as it performs simple behaviours: as the animal moves, parts of its brain light up under the microscope. For laboratory animals like fruit flies, which have relatively small brains, this lets us observe their brain activity right down to the level of individual brain cells. The brain directs movements via collective activity of the body's muscles. Our ability to track the activity of individual muscles is, however, more limited than our ability to observe single brain cells: even modern imaging technology still cannot monitor the activity of all the muscle cells in an animal's body as it moves about. Yet this is precisely the information that scientists need to fully understand how the brain generates behaviour. Fruit flies perform specific behaviours at certain stages of their life cycle. When the fly pupa begins to metamorphose into an adult insect, it performs a fixed sequence of movements involving a set number of muscles, which is called the pupal ecdysis sequence. This initial movement sequence and the rest of metamorphosis both occur within the confines of the pupal case, which is a small, hardened shell surrounding the whole animal. Elliott et al. set out to determine if the fruit fly pupa's ecdysis sequence could be used as a kind of model, to describe a simple behaviour at the level of individual muscles. Imaging experiments used fly pupae that were genetically engineered to produce an activity-dependent fluorescent protein in their muscle cells. Pupal cases were treated with a chemical to make them transparent, allowing easy observation of their visually 'labelled' muscles. This yielded a near-complete record of muscle activity during metamorphosis. Initially, individual muscles became active in small groups. The groups then synchronised with each other over the different regions of the pupa's body to form distinct movements, much as syllables join to form words. This synchronisation was key to progression through metamorphosis and was co-ordinated at each step by specialised nerve cells that produce or respond to specific hormones. These results reveal how the brain might direct muscle activity to produce movement patterns. In the future, Elliott et al. hope to compare data on muscle activity with comprehensive records of brain cell activity, to shed new light on how the brain, muscles, and other factors work together to control behaviour.


Assuntos
Drosophila/fisiologia , Músculos/anatomia & histologia , Músculos/fisiologia , Pupa/fisiologia , Animais , Comportamento Animal , Encéfalo/fisiologia , Biologia Computacional , Drosophila melanogaster/fisiologia , Hormônios de Invertebrado/fisiologia , Larva/fisiologia , Muda , Neurônios Motores , Receptores de Peptídeos
9.
Curr Biol ; 17(7): 624-9, 2007 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-17350263

RESUMO

Volatile anesthetics like halothane and enflurane are of interest to clinicians and neuroscientists because of their ability to preferentially disrupt higher functions that make up the conscious state. All volatiles were once thought to act identically; if so, they should be affected equally by genetic variants. However, mutations in two distinct genes, one in Caenorhabditis and one in Drosophila, have been reported to produce much larger effects on the response to halothane than enflurane [1, 2]. To see whether this anesthesia signature is adventitious or fundamental, we have identified orthologs of each gene and determined the mutant phenotype within each species. The fly gene, narrow abdomen (na), encodes a putative ion channel whose sequence places it in a unique family; the nematode gene, unc-79, is identified here as encoding a large cytosolic protein that lacks obvious motifs. In Caenorhabditis, mutations that inactivate both of the na orthologs produce an Unc-79 phenotype; in Drosophila, mutations that inactivate the unc-79 ortholog produce an na phenotype. In each organism, studies of double mutants place the genes in the same pathway, and biochemical studies show that proteins of the UNC-79 family control NA protein levels by a posttranscriptional mechanism. Thus, the anesthetic signature reflects an evolutionarily conserved role for the na orthologs, implying its intimate involvement in drug action.


Assuntos
Anestesia Geral , Caenorhabditis elegans/metabolismo , Drosophila melanogaster/metabolismo , Canais Iônicos/metabolismo , Anestésicos Inalatórios/farmacologia , Animais , Evolução Biológica , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Citosol/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Enflurano/farmacologia , Halotano/farmacologia , Canais Iônicos/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Fenótipo
10.
Prog Transplant ; 20(2): 118-24, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20642168

RESUMO

OBJECTIVE: Patients in acute cardiogenic shock are the most challenging patients to manage. Unless a mechanical circulatory assist device is placed, maintaining end-organ function can be difficult. Transporting cardiogenic shock patients to tertiary care centers for higher level care also is difficult. The Mayo Clinic Arizona uses a SWAT team approach to deploy a specialized medical or surgical multidisciplinary team to implant mechanical circulatory assist devices at referring hospitals and transport patients back to Mayo Clinic Arizona. RESULTS: The cardiac transport team at Mayo Clinic Arizona got 23 referrals from 15 local community hospitals from February 2006 to September 2009. The medical team deployed for transfers of 6 patients, 3 of whom survived to hospital discharge. The surgical transport team deployed for transfers of 17 patients (6 with left ventricular assist devices, 2 with right ventricular assist devices, 5 with biventricular assist devices, and 4 with extracorporeal membrane oxygenation), of whom 8 survived to hospital discharge. Ten of the 17 referrals (59%) required a surgeon to place a mechanical circulatory assist device at the referring hospital. CONCLUSION: The SWAT team approach allows cardiogenic shock patients to be stabilized at the referring hospital by heart failure and cardiac surgical specialists. If necessary, a surgeon from Mayo Clinic Arizona places a mechanical circulatory assist device at the referring hospital to stabilize the patient. Doing so allows safe transport back to the tertiary care center for higher level care and possible transplant evaluation with placement of a long-term durable device.


Assuntos
Coração Auxiliar , Equipe de Assistência ao Paciente/organização & administração , Transferência de Pacientes/organização & administração , Choque Cardiogênico/cirurgia , Transporte de Pacientes/organização & administração , Arizona , Humanos
11.
Front Neural Circuits ; 14: 603397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240047

RESUMO

The diversity and dense interconnectivity of cells in the nervous system present a huge challenge to understanding how brains work. Recent progress toward such understanding, however, has been fuelled by the development of techniques for selectively monitoring and manipulating the function of distinct cell types-and even individual neurons-in the brains of living animals. These sophisticated techniques are fundamentally genetic and have found their greatest application in genetic model organisms, such as the fruit fly Drosophila melanogaster. Drosophila combines genetic tractability with a compact, but cell-type rich, nervous system and has been the incubator for a variety of methods of neuronal targeting. One such method, called Split Gal4, is playing an increasingly important role in mapping neural circuits in the fly. In conjunction with functional perturbations and behavioral screens, Split Gal4 has been used to characterize circuits governing such activities as grooming, aggression, and mating. It has also been leveraged to comprehensively map and functionally characterize cells composing important brain regions, such as the central complex, lateral horn, and the mushroom body-the latter being the insect seat of learning and memory. With connectomics data emerging for both the larval and adult brains of Drosophila, Split Gal4 is also poised to play an important role in characterizing neurons of interest based on their connectivity. We summarize the history and current state of the Split Gal4 method and indicate promising areas for further development or future application.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Proteínas de Drosophila/genética , Vias Neurais/fisiologia , Neurônios/fisiologia , Fatores de Transcrição/genética , Animais , Conectoma , Drosophila , Drosophila melanogaster , Corpos Pedunculados
12.
iScience ; 23(5): 101108, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32408174

RESUMO

Eclosion hormone (EH) was originally identified as a brain-derived hormone capable of inducing the behavioral sequences required for molting across insect species. However, its role in this process (called ecdysis) has since been confounded by discrepancies in the effects of genetic and cellular manipulations of EH function in Drosophila. Although knock-out of the Eh gene results in severe ecdysis-associated deficits accompanied by nearly complete larval lethality, ablation of the only neurons known to express EH (i.e. Vm neurons) is only partially lethal and surviving adults emerge, albeit abnormally. Using new tools for sensitively detecting Eh gene expression, we show that EH is more widely expressed than previously thought, both within the nervous system and in somatic tissues, including trachea. Ablating all Eh-expressing cells has effects that closely match those of Eh gene knock-out; developmentally suppressing them severely disrupts eclosion. Our results thus clarify and extend the scope of EH action.

13.
Cardiol Clin ; 26(1): 73-7, vii, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18312907

RESUMO

The utilization of angiotensin-II attenuating agents is the standard of care in the management of patients with left ventricular dysfunction regardless of the etiology. The most effective agents of this group includes both angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor antagonists (ARB). Given the worse outcomes noted in those patients who have coronary artery disease, efforts to optimize appropriate pharmacotherapy in this population is imperative. There does appear to be some advantage in the combination of ACE+ARB in chronic left ventricular dysfunction patients. In those patients that have sustained a recent myocardial infarction with concomitant left ventricular dysfunction, the combination of ACE+ARB does not improve survival and in fact might exacerbate renal dysfunction as well as hypotension. The appropriate employment of agents that attenuate the effects of angiotensin-II should be a priority in the care and management of the left ventricular dysfunction patient.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Infarto do Miocárdio , Disfunção Ventricular Esquerda/tratamento farmacológico , Ensaios Clínicos como Assunto , Esquema de Medicação , Humanos
14.
J Am Heart Assoc ; 7(11)2018 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-29853444

RESUMO

BACKGROUND: Significant heterogeneity exists in practice patterns and algorithms used for cardiac screening before kidney transplant. Cardiorespiratory fitness, as measured by peak oxygen uptake (VO2peak), is an established validated predictor of future cardiovascular morbidity and mortality in both healthy and diseased populations. The literature supports its use among asymptomatic patients in abrogating the need for further cardiac testing. METHODS AND RESULTS: We outlined a pre-renal transplant screening algorithm to incorporate VO2peak testing among a population of asymptomatic high-risk patients (with diabetes mellitus and/or >50 years of age). Only those with VO2peak <17 mL/kg per minute (equivalent to <5 metabolic equivalents) underwent further noninvasive cardiac screening tests. We conducted a retrospective study of the a priori dichotomization of the VO2peak <17 versus ≥17 mL/kg per minute to determine negative and positive predictive value of future cardiac events and all-cause mortality. We report a high (>90%) negative predictive value, indicating that VO2peak ≥17 mL/kg per minute is effective to rule out future cardiac events and all-cause mortality. However, lower VO2peak had low positive predictive value and should not be used as a reliable metric to predict future cardiac events and/or mortality. In addition, a simple mathematical calculation documented a cost savings of ≈$272 600 in the cardiac screening among our study cohort of 637 patients undergoing evaluation for kidney and/or pancreas transplant. CONCLUSIONS: We conclude that incorporating an objective measure of cardiorespiratory fitness with VO2peak is safe and allows for a cost savings in the cardiovascular screening protocol among higher-risk phenotype (with diabetes mellitus and >50 years of age) being evaluated for kidney transplant.


Assuntos
Aptidão Cardiorrespiratória , Doenças Cardiovasculares/diagnóstico , Teste de Esforço , Falência Renal Crônica/cirurgia , Transplante de Rim , Consumo de Oxigênio , Liberação de Cirurgia/métodos , Adulto , Idoso , Doenças Cardiovasculares/fisiopatologia , Análise Custo-Benefício , Teste de Esforço/economia , Feminino , Custos de Cuidados de Saúde , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/fisiopatologia , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Liberação de Cirurgia/economia
15.
Curr Biol ; 12(24): 2152-8, 2002 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-12498692

RESUMO

A unique family of putative ion channels that are related to voltage-gated sodium and calcium channels has been identified in genomic and cDNA studies of metazoans. Aside from evidence for expression of family members in the nervous system, little is known about the operation of the channel or its functional significance. In the present study, this conserved family's sole Drosophila member, a gene known both as CG1517 and as Dmalpha1U, is shown to correspond to the narrow abdomen (na) gene and is the locus of a set of mutations that affect sensitivity to anesthetics. Immunohistochemistry of adult heads reveals that the channel is expressed in the neuropil of the central complex and optic lobe; expression is severely depressed in the mutants. In addition to previously described defects, the mutant phenotype is demonstrated here to include dysfunction in the coupling between light and locomotor behavior. Most dramatically, mutant flies have an inversion of relative locomotor activity in light versus dark. The involvement of the channel in daily rhythms of the fruit fly is especially provocative because the human ortholog lies in a candidate region linked to bipolar disorder, a disease frequently associated with altered diurnal behavior.


Assuntos
Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Canais Iônicos/metabolismo , Locomoção/fisiologia , Animais , Cátions , Escuridão , Feminino , Regulação da Expressão Gênica , Cabeça/fisiologia , Canais Iônicos/genética , Luz , Masculino , Dados de Sequência Molecular , Mutação , Fenótipo , Estimulação Luminosa
16.
Genetics ; 206(2): 775-784, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28363977

RESUMO

Efforts to map neural circuits have been galvanized by the development of genetic technologies that permit the manipulation of targeted sets of neurons in the brains of freely behaving animals. The success of these efforts relies on the experimenter's ability to target arbitrarily small subsets of neurons for manipulation, but such specificity of targeting cannot routinely be achieved using existing methods. In Drosophila melanogaster, a widely-used technique for refined cell type-specific manipulation is the Split GAL4 system, which augments the targeting specificity of the binary GAL4-UAS (Upstream Activating Sequence) system by making GAL4 transcriptional activity contingent upon two enhancers, rather than one. To permit more refined targeting, we introduce here the "Killer Zipper" (KZip+), a suppressor that makes Split GAL4 targeting contingent upon a third enhancer. KZip+ acts by disrupting both the formation and activity of Split GAL4 heterodimers, and we show how this added layer of control can be used to selectively remove unwanted cells from a Split GAL4 expression pattern or to subtract neurons of interest from a pattern to determine their requirement in generating a given phenotype. To facilitate application of the KZip+ technology, we have developed a versatile set of LexAop-KZip+ fly lines that can be used directly with the large number of LexA driver lines with known expression patterns. KZip+ significantly sharpens the precision of neuronal genetic control available in Drosophila and may be extended to other organisms where Split GAL4-like systems are used.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Neurônios/metabolismo , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Animais , Proteínas de Ligação a DNA/biossíntese , Proteínas de Drosophila/antagonistas & inibidores , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição/antagonistas & inibidores
17.
J Saudi Heart Assoc ; 28(1): 46-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26778904

RESUMO

Coronary artery anomaly is a rare postoperative coronary angiographic finding in heart transplant recipients. We report a case of anomalous origin of the right coronary artery in an asymptomatic 70-year-old heart transplant patient. Most coronary artery anomalies are benign, but surgical treatment may be necessary in major coronary artery anomalies that are known to have adverse outcomes.

18.
Am J Cardiol ; 118(4): 556-9, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27328958

RESUMO

Cardiac resynchronization therapy (CRT) reduces ventricular arrhythmia (VA) burden in some patients with heart failure, but its effect after left ventricular assist device (LVAD) implantation is unknown. We compared VA burden in patients with CRT devices in situ who underwent LVAD implantation and continued CRT (n = 39) to those who had CRT turned off before discharge (n = 26). Implantable cardioverter-defibrillator (ICD) shocks were significantly reduced in patients with continued CRT (1.5 ± 2.7 shocks per patient vs 5.5 ± 9.3 with CRT off, p = 0.014). There was a nonsignificant reduction in cumulative VA episodes per patient with CRT continued at discharge (42 ± 105 VA per patient vs 82 ± 198 with CRT off, p = 0.29). On-treatment analysis by whether CRT was on or off identified a significantly lower burden of VA (17 ± 1 per patient-year CRT on vs 37 ± 1 per patient-year CRT off, p <0.0001) and ICD shocks (1.2 ± 0.3 per patient-year CRT on vs 1.7 ± 0.3 per patient-year CRT off, p = 0.018). In conclusion, continued CRT is associated with significantly reduced ICD shocks and VA burden after LVAD implantation.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Coração Auxiliar , Taquicardia Ventricular/epidemiologia , Fibrilação Ventricular/epidemiologia , Adulto , Idoso , Dispositivos de Terapia de Ressincronização Cardíaca , Cardioversão Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/terapia , Fibrilação Ventricular/terapia
19.
J Am Coll Cardiol ; 43(5): 806-10, 2004 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-14998621

RESUMO

OBJECTIVES: We evaluated the association of mode of brain death with cardiac allograft vasculopathy. BACKGROUND: Explosive brain death (EBD) is accompanied by a sudden increase in intracranial pressure, with recruitment of pro-inflammatory cytokines, as well as adhesion cell and co-stimulatory molecules. Whether these early events influence the later development of cardiac allograft vasculopathy following heart transplantation remains unknown. METHODS: An inception cohort of 61 consecutive heart transplant recipients between 1993 and 1995 who underwent intravascular ultrasound examination of the coronary arteries were evaluated. Based on the mode of donor brain death, this cohort was divided into either an EBD group (n = 27) or non-EBD (n = 34), and the development of intimal thickness and cardiac events (sudden cardiac death, myocardial infarction, and need for coronary revascularization via percutaneous techniques or surgical bypass) was assessed. RESULTS: Despite similar posttransplant survival and distribution of nonimmunological and immunological variables, heart transplant recipients with EBD demonstrated greater intimal thickening (0.59 +/- 0.1 vs. 0.32 +/- 0.2 mm; p = 0.02) and higher cardiac events (37% vs. 12%; p = 0.01) when compared to those with non-EBD donors. Hearts from donors with EBD had lower survival (63 +/- 19 vs. 72 +/- 17 months) than with non-EBD donors (p = 0.04). CONCLUSIONS: Explosive brain death is a significant determinant for the late development of cardiac allograft vasculopathy and influences long-term allograft survival. Thus, strategies focusing on limitation of vascular allograft injury in the pre-engraftment phase of cardiac transplantation are warranted.


Assuntos
Morte Encefálica , Doença da Artéria Coronariana/epidemiologia , Transplante de Coração , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Causas de Morte , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Índice de Gravidade de Doença , Análise de Sobrevida , Ultrassonografia
20.
J Am Coll Cardiol ; 43(9): 1590-5, 2004 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-15120816

RESUMO

OBJECTIVES: This investigation evaluated the relationship between obesity and B-type natriuretic peptide (BNP) in heart failure. BACKGROUND: Obesity is a major risk factor for the development of heart failure, but the precise mechanisms remain uncertain. Physiologically, natriuretic peptides and lipolysis are closely linked. METHODS: A total of 318 patients with heart failure were evaluated between June 2001 and June 2002. Levels of BNP were compared in obese (body mass index [BMI] > or =30 kg/m(2)) and nonobese (BMI <30 kg/m(2)) patients with respect to New York Heart Association functional class and lean body weight-adjusted peak aerobic oxygen consumption. In a subset of 36 patients, plasma levels of tumor necrosis factor-alpha, interleukin-6, and soluble intercellular adhesion molecule-1 were measured. RESULTS: The population's BMI was 29.4 +/- 6.6 kg/m(2); 24% were lean (BMI <25 kg/m(2)), 31% overweight (BMI > or =25 to 29.9 kg/m(2)), and 45% obese (BMI > or =30 kg/m(2)). Obese patients were younger, more often African American, and more likely to have a history of antecedent hypertension, but less likely to have coronary artery disease and with only a trend toward diabetes mellitus. Levels of BNP were significantly lower in obese than in nonobese subjects (205 +/- 22 and 335 +/- 39 pg/ml, respectively; p = 0.0007), despite a similar severity of heart failure and cytokine levels. Multivariate regression analysis identified BMI as an independent negative correlate of BNP level. There were no differences in emergency department visits, heart failure hospitalization, or death between the obese and nonobese patients at 12-month follow-up. CONCLUSIONS: Our investigation indicates that a state of reduced natriuretic peptide level exists in the obese individual with heart failure.


Assuntos
Insuficiência Cardíaca/metabolismo , Peptídeo Natriurético Encefálico/sangue , Obesidade/metabolismo , Adulto , Fatores Etários , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Creatinina/sangue , Citocinas/metabolismo , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Louisiana , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/fisiopatologia , Valor Preditivo dos Testes , Fatores Sexuais , Estatística como Assunto , Volume Sistólico/fisiologia
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