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Neuronal growth, differentiation, homeostasis, viability, and injury response heavily rely on functional axonal transport (AT). Erroneous and disturbed AT may lead to accumulation of "disease proteins" such as tau, α-synuclein, or amyloid precursor protein causing various neurological disorders. Changes in AT often lead to observable behavioral consequences in C. elegans such as impeded movements, defects in touch response, chemosensation, and even egg laying. Long C. elegans neurons with clear distinguishable axons and dendrites provide an excellent platform to analyze AT. The possibility to relate changes in AT to neuronal defects that in turn lead to quantifiable changes in worm behavior allows for the advancement of neuropathological disease models. Even more, subsequent suppressor screens may aid in identifying genes responsible for observed behavioral changes providing a target for drug development to eventually delay or cure neurological diseases. Thus, in this chapter, we summarize critical methods to identify and quantify defects in axonal transport as well as exemplified behavioral assays that may relate to these defects.
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Transporte Axonal , Caenorhabditis elegans , Precursor de Proteína beta-Amiloide/genética , Animais , Transporte Axonal/fisiologia , Axônios/metabolismo , Comportamento Animal , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Neurônios/metabolismoRESUMO
Mitochondria and intermediate filament (IF) accumulations often occur during imbalanced axonal transport leading to various types of neurological diseases. It is still poorly understood whether a link between neuronal IFs and mitochondrial mobility exist. In Caenorhabditis elegans, among the 11 cytoplasmic IF family proteins, IFB-1 is of particular interest as it is expressed in a subset of sensory neurons. Depletion of IFB-1 leads to mild dye-filling and significant chemotaxis defects as well as reduced life span. Sensory neuron development is affected and mitochondrial transport is slowed down leading to reduced densities of these organelles. Mitochondria tend to cluster in neurons of IFB-1 mutants likely independent of the fission and fusion machinery. Oxygen consumption and mitochondrial membrane potential is measurably reduced in worms carrying mutations in the ifb-1 gene. Membrane potential also seems to play a role in transport such as carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone treatment led to increased directional switching of mitochondria. Mitochondria co-localize with IFB-1 in worm neurons and appear in a complex with IFB-1 in pull-down assays. In summary, we propose a model in which neuronal IFs may serve as critical (transient) anchor points for mitochondria during their long-range transport in neurons for steady and balanced transport.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Filamentos Intermediários/genética , Proteínas de Filamentos Intermediários/metabolismo , Filamentos Intermediários/metabolismo , Mitocôndrias/metabolismo , Células Receptoras Sensoriais/metabolismoRESUMO
OBJECTIVE: This research describes the clinical pathway and characteristics of two cohorts of patients. The first cohort consists of patients with a confirmed diagnosis of lung cancer while the second consists of patients with a solitary pulmonary nodule (SPN) and no evidence of lung cancer. Linked data from an electronic medical record and the Louisiana Tumor Registry were used in this investigation. MATERIALS AND METHODS: REACHnet is one of 9 clinical research networks (CRNs) in PCORnet®, the National Patient-Centered Clinical Research Network and includes electronic health records for over 8 million patients from multiple partner health systems. Data from Ochsner Health System and Tulane Medical Center were linked to Louisiana Tumor Registry (LTR), a statewide population-based cancer registry, for analysis of patient's clinical pathways between July 2013 and 2017. Patient characteristics and health services utilization rates by cancer stage were reported as frequency distributions. The Kaplan-Meier product limit method was used to estimate the time from index date to diagnosis by stage in lung cancer cohort. RESULTS: A total of 30,559 potentially eligible patients were identified and 2929 (9.58%) had primary lung cancer. Of these, 1496 (51.1%) were documented in LTR and their clinical pathway to diagnosis was further studied. Time to diagnosis varied significantly by cancer stage. A total of 24,140 patients with an SPN were identified in REACHnet and 15,978 (66.6%) had documented follow up care for 1 year. 1612 (10%) had no evidence of any work up for their SPN. The remaining 14,366 had some evidence of follow up, primarily office visits and additional chest imaging. CONCLUSION: In both cohorts multiple biopsies were evident in the clinical pathway. Despite clinical workup, 70% of patients in the lung cancer cohort had stage III or IV disease. In the SPN cohort, only 66% were identified as receiving a diagnostic work-up.
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Procedimentos Clínicos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Nódulo Pulmonar Solitário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial , Biópsia , Tomada de Decisão Clínica , Estudos de Coortes , Gerenciamento Clínico , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Padrões de Prática Médica , Sistema de Registros , Programa de SEER , Nódulo Pulmonar Solitário/diagnóstico , Adulto JovemRESUMO
PURPOSE: To describe the distribution of diagnostic procedures, rates of complications, and total cost of biopsies for patients with lung cancer. PATIENTS AND METHODS: Observational study using data from IBM Marketscan® Databases for continuously insured adult patients with a primary lung cancer diagnosis and treatment between July 2013 and June 2017. Costs of lung cancer diagnosis covered 6 months prior to index biopsy through treatment. Costs of chest CT scans, biopsy, and post-procedural complications were estimated from total payments. Costs of biopsies incidental to inpatient admissions were estimated by comparable outpatient biopsies. RESULTS: The database included 22,870 patients who had a total of 37,160 biopsies, of which 16,009 (43.1%) were percutaneous, 14,997 (40.4%) bronchoscopic, 4072 (11.0%) surgical and 2082 (5.6%) mediastinoscopic. Multiple biopsies were performed on 41.9% of patients. The most common complications among patients receiving only one type of biopsy were pneumothorax (1304 patients, 8.4%), bleeding (744 patients, 4.8%) and intubation (400 patients, 2.6%). However, most complications did not require interventions that would add to costs. Median total costs were highest for inpatient surgical biopsies ($29,988) and lowest for outpatient percutaneous biopsies ($1028). Repeat biopsies of the same type increased costs by 40-80%. Complications account for 13% of total costs. CONCLUSION: Costs of biopsies to confirm lung cancer diagnosis vary substantially by type of biopsy and setting. Multiple biopsies, inpatient procedures and complications result in higher costs.
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OBJECTIVE: This study aimed to describe the frequency and distribution of biopsy procedures for patients diagnosed and treated for primary lung cancer. STUDY DESIGN: Retrospective cohort study within an administrative database. MATERIALS & METHODS: This observational study used data from the IBM MarketScan® Databases between 2013 and 2015. RESULTS: The total number of lung biopsies performed among eligible subjects was 32,814; an average of 1.7 biopsies per patient. Bronchoscopy and percutaneous approaches accounted for 95% of all procedures. Complication rates by procedure are remarkably similar irrespective of biopsy frequency. CONCLUSION: Nearly half (46%) of patients in this population experienced multiple biopsies prior to diagnosis. Further, biopsy choice or sequence in patients receiving multiple procedures was unpredictable.
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UNC-104 is the Caenorhabditis elegans homolog of kinesin-3 KIF1A known for its fast shuffling of synaptic vesicle protein transport vesicles in axons. SYD-2 is the homolog of liprin-α in C. elegans known to activate UNC-104; however, signals that trigger SYD-2 binding to the motor remain unknown. Because SYD-2 is a substrate of PTP-3/LAR PTPR, we speculate a role of this phosphatase in SYD-2-mediated motor activation. Indeed, coimmunoprecipitation assays revealed increased interaction between UNC-104 and SYD-2 in ptp-3 knockout worms. Intramolecular FRET analysis in living nematodes demonstrates that SYD-2 largely exists in an open conformation state in ptp-3 mutants. These assays also revealed that nonphosphorylatable SYD-2 (Y741F) exists predominately in folded conformations, while phosphomimicking SYD-2 (Y741E) primarily exists in open conformations. Increased UNC-104 motor clustering was observed along axons likely as a result of elevated SYD-2 scaffolding function in ptp-3 mutants. Also, both motor velocities as well as cargo transport speeds were visibly increased in neurons of ptp-3 mutants. Lastly, epistatic analysis revealed that PTP-3 is upstream of SYD-2 to regulate its intramolecular folding.
Assuntos
Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Dobramento de Proteína , Proteínas Tirosina Fosfatases/metabolismo , Animais , Caenorhabditis elegans/genética , Epistasia Genética , Regulação da Expressão Gênica , Modelos Biológicos , Mutação/genética , Ligação Proteica/genética , Conformação ProteicaRESUMO
Model organisms are increasingly used to study and understand how neurofilament (NF)-based neurological diseases develop. However, whether a NF homolog exists in C. elegans remains unclear. We characterize TAG-63 as a NF-like protein with sequence homologies to human NEFH carrying various coiled coils as well as clustered phosphorylation sites. TAG-63 also exhibits features of NFL such as a molecular weight of around 70 kD, the lack of KSP repeats and the ability to form 10 nm filamentous structures in transmission electron micrographs. An anti-NEFH antibody detects a band at the predicted molecular weight of TAG-63 in Western blots of whole worm lysates and this band cannot be detected in tag-63 knockout worms. A transcriptional tag-63 reporter expresses in a broad range of neurons, and various anti-NFH antibodies stain worm neurons with an overlapping expression of axonal vesicle transporter UNC-104(KIF1A). Cultured neurons grow shorter axons when incubating with drugs known to disintegrate the NF network and rhodamine-labeled in vitro reconstituted TAG-63 filaments disintegrate upon drug exposure. Speeds of UNC-104 motors are diminished in tag-63 mutant worms with visibly increased accumulations of motors along axons. UNC-104/TAG-63 and SNB-1/TAG-63 not only colocalize in neurons but also revealed positive BiFC (bimolecular fluorescence assay) signals. In summary, we identified and characterized TAG-63 in C. elegans, and demonstrate that lack of this protein limits axonal transport efficiencies. Additionally, this study would aid in developing NF-related disease models in the future.
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Transporte Axonal , Proteínas de Caenorhabditis elegans , Animais , Animais Geneticamente Modificados/fisiologia , Transporte Axonal/fisiologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/fisiologiaRESUMO
Bidirectional cargo transport in neurons can be explained by two models: the "tug-of-war model" for short-range transport, in which several kinesin and dynein motors are bound to the same cargo but travel in opposing directions, and by the "motor coordination model" for long-range transport, in which small adaptors or the cargo itself activates or deactivates opposing motors. Direct interactions between the major axonal transporter kinesin-3 UNC-104(KIF1A) and the dynein/dynactin complex remains unknown. In this study, we dissected and evaluated the interaction sites between UNC-104 and dynein as well as between UNC-104 and dynactin using yeast two-hybrid assays. We found that the DYLT-1(Tctex) subunit of dynein binds near the coiled coil 3 (CC3) of UNC-104, and that the DYRB-1(Roadblock) subunit binds near the CC2 region of UNC-104. Regarding dynactin, we specifically revealed strong interactions between DNC-6(p27) and the FHA-CC3 stretch of UNC-104, as well as between the DNC-5(p25) and the CC2-CC3 region of UNC-104. Motility analysis of motors and cargo in the nervous system of Caenorhabditis elegans revealed impaired transport of UNC-104 and synaptic vesicles in dynein and dynactin mutants (or in RNAi knockdown animals). Further, in these mutants UNC-104 clustering along axons was diminished. Interestingly, when dynamic UNC-104 motors enter a stationary UNC-104 cluster their dwelling times are increased in dynein mutants (suggesting that dynein may act as an UNC-104 activator). In summary, we provide novel insights on how UNC-104 interacts with the dynein/dynactin complex and how UNC-104 driven axonal transport depends on dynein/dynactin in C. elegans neurons.
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Transporte Axonal/fisiologia , Proteínas de Caenorhabditis elegans/fisiologia , Complexo Dinactina/fisiologia , Dineínas/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Domínios e Motivos de Interação entre Proteínas/fisiologia , Animais , Transporte Axonal/genética , Axônios/metabolismo , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Ensaios de Migração Celular , Complexo Dinactina/genética , Dineínas/genética , Cinesinas , Proteínas Associadas aos Microtúbulos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Vesículas Sinápticas/metabolismoRESUMO
We utilized size-tunable gold nanoparticles (Au NPs) to investigate the toxicogenomic responses of the model organism Caenorhabditis elegans. We demonstrated that the nematode C. elegans can uptake Au NPs coated with or without 11-mercaptoundecanoic acid (MUA), and Au NPs are detectable in worm intestines using X-ray microscopy and confocal optical microscopy. After Au NP exposure, C. elegans neurons grew shorter axons, which may have been related to the impeded worm locomotion behavior detected. Furthermore, we determined that MUA to Au ratios of 0.5, 1 and 3 reduced the worm population by more than 50% within 72 hours. In addition, these MUA to Au ratios reduced the worm body size, thrashing frequency (worm mobility) and brood size. MTT assays were employed to analyze the viability of cultured C. elegans primary neurons exposed to MUA-Au NPs. Increasing the MUA to Au ratios increasingly reduced neuronal survival. To understand how developmental changes (after MUA-Au NP treatment) are related to changes in gene expression, we employed DNA microarray assays and identified changes in gene expression (e.g., clec-174 (involved in cellular defense), cut-3 and fil-1 (both involved in body morphogenesis), dpy-14 (expressed in embryonic neurons), and mtl-1 (functions in metal detoxification and homeostasis)).
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Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/genética , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Animais , Calibragem , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/normas , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/patologia , Tamanho da Partícula , Testes de ToxicidadeRESUMO
We employ model organism Caenorhabditis elegans to effectively study the toxicology of anatase and rutile phase titanium dioxide (TiO2) nanoparticles (NPs). The experimental results show that nematode C. elegans can take up fluorescein isothiocyanate-labeled TiO2 NPs and that both anatase and rutile TiO2 NPs can be detected in the cytoplasm of cultured primary neurons imaged by transmission electron microscopy. After TiO2 NP exposure, these neurons also grow shorter axons, which may be related to the detected impeded worm locomotion behavior. Furthermore, anatase TiO2 NPs did not affect the worm's body length; however, we determined that a concentration of 500 µg/mL of anatase TiO2 NPs reduced the worm population by 50% within 72 h. Notably, rutile TiO2 NPs negatively affect both the body size and worm population. Worms unable to enter the L4 larval stage explain a severe reduction in the worm population at TiO2 NPs LC50/3d. To obtain a better understanding of the cellular mechanisms involved in TiO2 NP intoxication, DNA microarray assays were employed to determine changes in gene expression in the presence or absence of TiO2 NP exposure. Our data reveal that three genes (with significant changes in expression levels) were related to metal binding or metal detoxification (mtl-2, C45B2.2, and nhr-247), six genes were involved in fertility and reproduction (mtl-2, F26F2.3, ZK970.7, clec-70, K08C9.7, and C38C3.7), four genes were involved in worm growth and body morphogenesis (mtl-2, F26F2.3, C38C3.7, and nhr-247), and five genes were involved in neuronal function (C41G6.13, C45B2.2, srr-6, K08C9.7, and C38C3.7).
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Nanopartículas Metálicas , Animais , Caenorhabditis elegans , Locomoção , Neurônios , TitânioRESUMO
To understand how ciliopathies such as polycystic kidney disease or Bardet-Biedl syndrome develop, we need to understand the basic molecular mechanisms underlying cilium development. Cilium growth depends on the presence of functional intraflagellar transport (IFT) machinery, and we hypothesized that various kinases and phosphatases might be involved in this regulatory process. A candidate screen revealed two kinases, PKG-1 (a cGMP-dependent protein kinase) and GCK-2 (a mitogen-activated protein kinase kinase kinase kinase 3 [MAP4K3] kinase involved in mTOR signaling), significantly affecting dye filling, chemotaxis, cilium morphology, and IFT component distribution. PKG-1 and GCK-2 show similar expression patterns in Caenorhabditis elegans cilia and colocalize with investigated IFT machinery components. In pkg-1 mutants, a high level of accumulation of kinesin-2 OSM-3 in distal segments was observed in conjunction with an overall reduction of anterograde and retrograde IFT particle A transport, likely as a function of reduced tubulin acetylation. In contrast, in gck-2 mutants, both kinesin-2 motility and IFT particle A motility were significantly elevated in the middle segments, in conjunction with increased tubulin acetylation, possibly the cause of longer cilium growth. Observed effects in mutants can be also seen in manipulating upstream and downstream effectors of the respective cGMP and mTOR pathways. Importantly, transmission electron microscopy (TEM) analysis revealed no structural changes in cilia of pkg-1 and gck-2 mutants.
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Proteínas de Caenorhabditis elegans/metabolismo , Cílios/fisiologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células Receptoras Sensoriais/fisiologia , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/crescimento & desenvolvimento , Cílios/metabolismo , Cinesinas/metabolismo , Microscopia Eletrônica de Transmissão/métodos , Células Receptoras Sensoriais/metabolismo , Transdução de Sinais , Tubulina (Proteína)/metabolismoRESUMO
BACKGROUND: In very low birth weight infants abdominal emergency surgery may result in ileostomy formation. We observed a frequent stoma complications in these patients. This retrospective analysis put light on ileostomy-related problems and complications in very low birth weight (VLBW) infants. MATERIALS AND METHODS: In a seven-year retrospective chart review (2008 - 2014) infants with ileostomy formation weighing less than 1500 grams at time of operation were identified and reviewed. Data analysis included demographic data, complications and short term outcomes. RESULTS: Thirty patients were included. Ileostomy was formed for spontaneous intestinal perforation (SIP) (n=17), meconium obstruction of prematurity (MOP) (n=6), midgut volvulus (MV) (n=5), necrotizing enterocolitis (NEC) (n=1) and Hirschsprung's disease (HD) (n=1). Three patients died before ileostomy reversal was considered. In seven patients planned ileostomy reversal was done. Twenty infants had stoma related complications (stoma prolapse, prestomal obstruction, stoma retraction, high output stoma, peristomal skin excoriation, and stomal ischemia). Complications did not correlate with underlying diseases. Stomal complications necessitated earlier stoma reversal (mean 62 days). Postoperative complications after stoma reversal occurred in three children (wound dehiscence, adhesion ileus, anastomotic stricture). CONCLUSIONS: Although ileostomy related complications are frequent in very low birth weight infants, mortality is low. Morbidity is manageable.
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Kinesin-3 UNC-104(KIF1A) is the major axonal transporter of synaptic vesicles. Employing yeast two-hybrid and co-immunoprecipitation (Co-IP) assays, we characterized a LIN-2(CASK) binding site overlapping with that of reported UNC-104 activator protein SYD-2(Liprin-α) on the motor's stalk domain. We identified the L27 and GUK domains of LIN-2 to be the most critical interaction domains for UNC-104. Further, we demonstrated that the L27 domain interacts with the sterile alpha motifs (SAM) domains of SYD-2, while the GUK domain is able to interact with both the coiled coils and SAM domains of SYD-2. LIN-2 and SYD-2 colocalize in Caenorhabditis elegans neurons and display interactions in bimolecular fluorescence complementation (BiFC) assays. UNC-104 motor motility and Synaptobrevin-1 (SNB-1) cargo transport are largely diminished in neurons of LIN-2 knockout worms, which cannot be compensated by overexpressing SYD-2. The absence of the motor-activating function of LIN-2 results in increased motor clustering along axons, thus retaining SNB-1 cargo in cell bodies. LIN-2 and SYD-2 both positively affect the velocity of UNC-104, however, only LIN-2 is able to efficiently elevate the motor's run lengths. From our study, we conclude that LIN-2 and SYD-2 act in a functional complex to regulate the motor with LIN-2 being the more prominent activator.
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Transporte Axonal/fisiologia , Axônios/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Movimento Celular/fisiologia , Proteínas de Helminto/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas do Tecido Nervoso/genética , Fosfoproteínas/metabolismoAssuntos
Anormalidades Múltiplas , Síndrome Nefrótica/congênito , Glicosilação , Humanos , Mutação , TransferrinaRESUMO
PURPOSE: C-arm radiographs are commonly used for intraoperative image guidance in surgical interventions. Fluoroscopy is a cost-effective real-time modality, although image quality can vary greatly depending on the target anatomy. Cone-beam computed tomography (CBCT) scans are sometimes available, so 2D-3D registration is needed for intra-procedural guidance. C-arm radiographs were registered to CBCT scans and used for 3D localization of peritumor fiducials during a minimally invasive thoracic intervention with a da Vinci Si robot. METHODS: Intensity-based 2D-3D registration of intraoperative radiographs to CBCT was performed. The feasible range of X-ray projections achievable by a C-arm positioned around a da Vinci Si surgical robot, configured for robotic wedge resection, was determined using phantom models. Experiments were conducted on synthetic phantoms and animals imaged with an OEC 9600 and a Siemens Artis zeego, representing the spectrum of different C-arm systems currently available for clinical use. RESULTS: The image guidance workflow was feasible using either an optically tracked OEC 9600 or a Siemens Artis zeego C-arm, resulting in an angular difference of Δθ:â¼ 30°. The two C-arm systems provided TRE mean ≤ 2.5 mm and TRE mean ≤ 2.0 mm, respectively (i.e., comparable to standard clinical intraoperative navigation systems). CONCLUSIONS: C-arm 3D localization from dual 2D-3D registered radiographs was feasible and applicable for intraoperative image guidance during da Vinci robotic thoracic interventions using the proposed workflow. Tissue deformation and in vivo experiments are required before clinical evaluation of this system.
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Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Robótica , Cirurgia Assistida por Computador/métodos , Animais , Fluoroscopia/métodos , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/métodosRESUMO
BACKGROUND: This is a single-center case series about the rare condition of volvulus without malposition and/or malrotation (VWM) in preterm babies. We focus on diagnostic difficulties, and our results should help to distinguish VWM as a distinct entity different from classical volvulus and segmental volvulus. MATERIALS AND METHODS: Medical chart review of infants with VWM from 2003-2012 was used. RESULTS: A total of 15 patients were identified. All of them had volvulus in the absence of intestinal malposition or other associated intestinal pathologies. All patients were born prematurely. Emergency laparotomy was necessary in all 15 patients. Two groups were identified. Group 1 includes four patients with typical signs of meconium obstruction of prematurity (MOP). Small bowel resection was only necessary in one of these four patients, all survived without residual intestinal lesions. Group 2 consists of 11 patients without signs of MOP-small bowel resection and temporary enterostomy were necessary in all these children. Four patients presented with pneumatosis intestinalis on the abdominal plain film, suggesting necrotizing enterocolitis. Although two infants died, the survivors showed complete recovery. CONCLUSIONS: VWM is a distinct disease of prematurity. When associated with MOP, VWM has a favorable outcome of treatment. In contrast, VWM occurring in the absence of signs of meconium obstruction requires small bowel resection. VWM primarily affects the top of the midgut (ileum). Because of absent malposition, presentation of VWM may be uncharacteristic. Pneumatosis intestinalis in advanced VWM may lead to diagnostic difficulties and a delay in treatment.
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Procedimentos Cirúrgicos do Sistema Digestório , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/cirurgia , Volvo Intestinal/diagnóstico , Volvo Intestinal/cirurgia , Bases de Dados Factuais , Diagnóstico Diferencial , Enterostomia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/mortalidade , Doenças do Recém-Nascido/cirurgia , Recém-Nascido Prematuro , Obstrução Intestinal/mortalidade , Volvo Intestinal/mortalidade , Intestino Delgado/cirurgia , MecônioRESUMO
SYD-2/liprin-α is a multi-domain protein that associates with and recruits multiple active zone molecules to form presynaptic specializations. Given SYD-2's critical role in synapse formation, its synaptogenic ability is likely tightly regulated. However, mechanisms that regulate SYD-2 function are poorly understood. In this study, we provide evidence that SYD-2's function may be regulated by interactions between its coiled-coil (CC) domains and sterile α-motif (SAM) domains. We show that the N-terminal CC domains are necessary and sufficient to assemble functional synapses while C-terminal SAM domains are not, suggesting that the CC domains are responsible for the synaptogenic activity of SYD-2. Surprisingly, syd-2 alleles with single amino acid mutations in the SAM domain show strong loss of function phenotypes, suggesting that SAM domains also play an important role in SYD-2's function. A previously characterized syd-2 gain-of-function mutation within the CC domains is epistatic to the loss-of-function mutations in the SAM domain. In addition, yeast two-hybrid analysis showed interactions between the CC and SAM domains. Thus, the data is consistent with a model where the SAM domains regulate the CC domain-dependent synaptogenic activity of SYD-2. Taken together, our study provides new mechanistic insights into how SYD-2's activity may be modulated to regulate synapse formation during development.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Fosfoproteínas/metabolismo , Sinapses/metabolismo , Alelos , Motivos de Aminoácidos , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Peptídeos e Proteínas de Sinalização Intercelular , Mutação de Sentido Incorreto , Fenótipo , Fosfoproteínas/química , Fosfoproteínas/genética , Ligação Proteica , Estrutura Terciária de ProteínaRESUMO
OBJECTIVES: B-type natriuretic peptides have been shown to enable differentiation between heart and lung diseases in adults and children. In neonates, the role of natriuretic peptides for diagnosis of congenital heart defect (CHD) is not yet ascertained. The purpose of this single-center prospective study was to investigate aminoterminal B-type natriuretic peptide concentrations and their time courses during the first 5 days of life in neonates with CHD compared with neonates with respiratory distress. DESIGN: Single-center prospective study. SETTING: Tertiary-care neonatal ICU. PATIENTS: Aminoterminal B-type natriuretic peptide levels of 40 neonates with arterial duct-dependent CHD and of 40 neonates with respiratory distress without CHD were analyzed on the first, second, third, and fifth day of life. MAIN RESULTS: Mean aminoterminal B-type natriuretic peptide concentrations in the CHD group were significantly higher on the second (14191 vs. 4872 pg/mL), third (17790 vs. 3524 pg/mL), and fifth day (17015 vs. 4044 pg/mL), but not on the first day of life. Repeated measurements analysis of variance revealed a significantly different time course of aminoterminal B-type natriuretic peptide concentrations between the two groups. CONCLUSIONS: On the first day of life, aminoterminal B-type natriuretic peptide cannot differentiate between CHD and respiratory distress without CHD in the neonate. From the second day onwards, aminoterminal B-type natriuretic peptide in neonates with CHD shows higher values and a different time course and enables differentiation between CHD and respiratory distress due to other than cardiac reasons.
Assuntos
Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Insuficiência Respiratória/sangue , Insuficiência Respiratória/diagnóstico , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Cardiopatias Congênitas/fisiopatologia , Frequência Cardíaca , Humanos , Recém-Nascido , Masculino , Curva ROC , Insuficiência Respiratória/fisiopatologia , Fatores de TempoRESUMO
BACKGROUND: Laparoscopic antireflux surgery is highly effective in patients with uncomplicated gastroesophageal reflux disease (GERD). However, long-term failure rates in paraesophageal hernia (PEH) and Barrett's metaplasia (BE) are higher and warrant a more durable repair. Outcomes for the laparoscopic Nissen fundoplication (LNF) and Hill repair (LHR) are equivalent, but their anatomic components are different and may complement each other (Aye R Ann Thorac Surg, 2012). We designed and tested the feasibility and safety of an operation that combines the essential components of each repair. METHODS: A prospective, phase II pilot study was performed on patients with symptomatic giant PEH hernias and/or GERD with nondysplastic Barrett's metaplasia. Pre- and postoperative esophagogastroduodenoscopy (EGD), upper gastrointestinal study (UGI), 48-hour pH testing, manometry, and three quality-of-life metrics were obtained. RESULTS: Twenty-four patients were enrolled in the study. Three patients did not complete the planned procedure, leaving 21 patients, including 12 with PEH, 7 with BE, and 2 with both. There were no 30-day or in-hospital mortalities. At a median follow-up of 13 (range 6.4-30.2) months, there were no reoperations or clinical recurrences. Two patients required postoperative dilation for dysphagia, with complete resolution. Mean DeMeester scores improved from 54.3 to 7.5 (p < 0.0036). Mean lower esophageal sphincter pressures (LESP) increased from 8.9 to 21.3 mmHg (p < 0.013). Mean short-term and long-term QOLRAD scores improved from 4.09 at baseline to 6.04 and 6.48 (p < 0.0001). Mean short-term and long-term GERD-HQRL scores improved from 22.9 to 7.5 and 6.9 (p < 0.03). Mean long-term Dysphagia Severity Score Index improved from 33.3 to 40.6 (p < 0.064). CONCLUSIONS: The combination of a Nissen plus Hill hybrid reconstruction of the gastroesophageal junction (GEJ) is technically feasible, safe, and not associated with increased side effects. Short-term clinical results in PEH and BE suggest that this may be an effective repair, supporting the value of further study.