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1.
NMR Biomed ; : e5195, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845018

RESUMO

The neuronal tricarboxylic acid and glutamate/glutamine (Glu/Gln) cycles play important roles in brain function. These processes can be measured in vivo using dynamic 1H-[13C] MRS during administration of 13C-labeled glucose. Proton-observed carbon-edited (POCE) MRS enhances the signal-to-noise ratio (SNR) compared with direct 13C-MRS. Ultra-high field further boosts the SNR and increases spectral dispersion; however, even at 7 T, Glu and Gln 1H-resonances may overlap. Further gain can be obtained with selective POCE (selPOCE). Our aim was to create a setup for indirect dynamic 1H-[13C] MRS in the human brain at 7 T. A home-built non-shielded transmit-receive 13C-birdcage head coil with eight transmit-receive 1H-dipole antennas was used together with a 32-channel 1H-receive array. Electromagnetic simulations were carried out to ensure that acquisitions remained within local and global head SAR limits. POCE-MRS was performed using slice-selective excitation with semi-localization by adiabatic selective refocusing (sLASER) and stimulated echo acquisition mode (STEAM) localization, and selPOCE-MRS using STEAM. Sequences were tested in a phantom containing non-enriched Glu and Gln, and in three healthy volunteers during uniformly labeled 13C-glucose infusions. In one subject the voxel position was alternated between bi-frontal and bi-occipital placement within one session. [4-13C]Glu-H4 and [4-13C]Gln-H4 signals could be separately detected using both STEAM-POCE and STEAM-selPOCE in the phantom. In vivo, [4,5-13C]Glx could be detected using both sLASER-POCE and STEAM-POCE, with similar sensitivities, but [4,5-13C]Glu and [4,5-13C]Gln signals could not be completely resolved. STEAM-POCE was alternately performed bi-frontal and bi-occipital within a single session without repositioning of the subject, yielding similar results. With STEAM-selPOCE, [4,5-13C]Glu and [4,5-13C]Gln could be clearly separated. We have shown that with our setup indirect dynamic 1H-[13C] MRS at 7 T is feasible in different locations in the brain within one session, and by using STEAM-selPOCE it is possible to separate Glu from Gln in vivo while obtaining high quality spectra.

2.
BMC Med Educ ; 24(1): 766, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014386

RESUMO

PURPOSE: Transdisciplinarity has been described as a fusion of theories, methods, and expertise across disciplinary boundaries to address complex, global problems. This approach has coincided with an increase in US medical schools offering masters degrees along with an MD degree to equip medical students to practice in complex, interconnected health systems. This study focused on medical schools that graduate the most dual degree students per year and explored the alignment of such programs with a transdisciplinary approach. METHODS: We identified 19 allopathic medical schools that annually graduated an average of 10 or more dual-degree students from 2015-2020. We surveyed these schools and asked participants to describe the reason(s) their institutions offered dual-degree programs. Two authors coded the narrative responses from the survey. RESULTS: Responses were received from 17 of the 19 schools. The analysis of participants' responses regarding their institutions' purpose for offering dual programs revealed several themes associated with a transdisciplinary approach to training. The most common themes were expand skill sets beyond a medical degree (73%), provide opportunity for interdisciplinary collaboration (67%), expand career interest and goals (60%), develop leaders (53%), enhance residency applications (47%) and further the institution's vision and mission (45%). CONCLUSIONS: This study is the first comprehensive evaluation of MD/Masters programs in the United States that includes a summary of the medical schools with the largest dual degree programs and their reasons for offering them. The findings support the hypothesis that allopathic medical schools recognize the need for a transdisciplinary approach to prepare students for the complexities in healthcare. These programs provide students with opportunities for additional areas of expertise, leadership development, enhancement of competitiveness for residency application, and interdisciplinary collaboration. Medical schools without dual-degree programs may consider developing these programs to provide benefits to students and institutions.


Assuntos
Educação de Pós-Graduação em Medicina , Faculdades de Medicina , Humanos , Estados Unidos , Currículo , Estudantes de Medicina , Comunicação Interdisciplinar , Inquéritos e Questionários
3.
Mol Phylogenet Evol ; 184: 107786, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37105244

RESUMO

Campylobacter is a bacterial genus associated with community outbreaks and gastrointestinal symptoms. Studies on Campylobacter generally focus on specific pathogenic species such as C. coli and C. jejuni. Currently, there are thousands of publicly available Campylobacter genomes, allowing a more complete assessment of the genus diversity. In this work, we report a network-based analysis of all available Campylobacter genomes to explore the genus structure and diversity, revealing potentially new species and elucidating genus features. We also hypothesize that the previously established Clade III of C. coli is in fact a novel species (referred here as Campylobacter spp12). Finally, we found a negative correlation between pangenome fluidity and saturation coefficient, with potential implications to the lifestyles of distinct Campylobacter species. Since pangenome analysis depends on the number of available genomes, this correlation could help estimate pangenome metrics of Campylobacter species with less sequenced genomes, helping understand their lifestyle and niche adaptation. Together, our results indicate that the Campylobacter genus should be re-evaluated, with particular attention to the interplay between genome structure and niche segregation.


Assuntos
Campylobacter , Campylobacter/genética , Filogenia , Genoma Bacteriano , Genômica/métodos , Bactérias/genética
4.
J Magn Reson Imaging ; 57(5): 1451-1461, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36098348

RESUMO

BACKGROUND: Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT) can reconstruct whole-brain multi-parametric quantitative maps (eg, T1 , T2 ) from a 5-minute MR acquisition. These quantitative maps can be leveraged for synthetization of clinical image contrasts. PURPOSE: The objective was to assess image quality and overall diagnostic accuracy of synthetic MR-STAT contrasts compared to conventional contrast-weighted images. STUDY TYPE: Prospective cross-sectional clinical trial. POPULATION: Fifty participants with a median age of 45 years (range: 21-79 years) consisting of 10 healthy participants and 40 patients with neurological diseases (brain tumor, epilepsy, multiple sclerosis or stroke). FIELD STRENGTH/SEQUENCE: 3T/Conventional contrast-weighted imaging (T1 /T2 weighted, proton density [PD] weighted, and fluid-attenuated inversion recovery [FLAIR]) and a MR-STAT acquisition (2D Cartesian spoiled gradient echo with varying flip angle preceded by a non-selective inversion pulse). ASSESSMENT: Quantitative T1 , T2 , and PD maps were computed from the MR-STAT acquisition, from which synthetic contrasts were generated. Three neuroradiologists blinded for image type and disease randomly and independently evaluated synthetic and conventional datasets for image quality and diagnostic accuracy, which was assessed by comparison with the clinically confirmed diagnosis. STATISTICAL TESTS: Image quality and consequent acceptability for diagnostic use was assessed with a McNemar's test (one-sided α = 0.025). Wilcoxon signed rank test with a one-sided α = 0.025 and a margin of Δ = 0.5 on the 5-level Likert scale was used to assess non-inferiority. RESULTS: All data sets were similar in acceptability for diagnostic use (≥3 Likert-scale) between techniques (T1 w:P = 0.105, PDw:P = 1.000, FLAIR:P = 0.564). However, only the synthetic MR-STAT T2 weighted images were significantly non-inferior to their conventional counterpart; all other synthetic datasets were inferior (T1 w:P = 0.260, PDw:P = 1.000, FLAIR:P = 1.000). Moreover, true positive/negative rates were similar between techniques (conventional: 88%, MR-STAT: 84%). DATA CONCLUSION: MR-STAT is a quantitative technique that may provide radiologists with clinically useful synthetic contrast images within substantially reduced scan time. EVIDENCE LEVEL: 1 Technical Efficacy: Stage 2.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Encéfalo/patologia , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Estudos Prospectivos
5.
Eur J Nucl Med Mol Imaging ; 49(2): 481-491, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550492

RESUMO

PURPOSE: CXCR4 (over)expression is found in multiple human cancer types, while expression is low or absent in healthy tissue. In glioblastoma it is associated with a poor prognosis and more extensive infiltrative phenotype. CXCR4 can be targeted by the diagnostic PET agent [68Ga]Ga-Pentixafor and its therapeutic counterpart [177Lu]Lu-Pentixather. We aimed to investigate the expression of CXCR4 in glioblastoma tissue to further examine the potential of these PET agents. METHODS: CXCR4 mRNA expression was examined using the R2 genomics platform. Glioblastoma tissue cores were stained for CXCR4. CXCR4 staining in tumor cells was scored. Stained tissue components (cytoplasm and/or nuclei of the tumor cells and blood vessels) were documented. Clinical characteristics and information on IDH and MGMT promoter methylation status were collected. Seven pilot patients with recurrent glioblastoma underwent [68Ga]Ga-Pentixafor PET; residual resected tissue was stained for CXCR4. RESULTS: Two large mRNA datasets (N = 284; N = 540) were assesed. Of the 191 glioblastomas, 426 cores were analyzed using immunohistochemistry. Seventy-eight cores (23 tumors) were CXCR4 negative, while 18 cores (5 tumors) had both strong and extensive staining. The remaining 330 cores (163 tumors) showed a large inter- and intra-tumor variation for CXCR4 expression; also seen in the resected tissue of the seven pilot patients-not directly translatable to [68Ga]Ga-Pentixafor PET results. Both mRNA and immunohistochemical analysis showed CXCR4 negative normal brain tissue and no significant correlation between CXCR4 expression and IDH or MGMT status or survival. CONCLUSION: Using immunohistochemistry, high CXCR4 expression was found in a subset of glioblastomas as well as a large inter- and intra-tumor variation. Caution should be exercised in directly translating ex vivo CXCR4 expression to PET agent uptake. However, when high CXCR4 expression can be identified with [68Ga]Ga-Pentixafor, these patients might be good candidates for targeted radionuclide therapy with [177Lu]Lu-Pentixather in the future.


Assuntos
Complexos de Coordenação , Glioblastoma , Radioisótopos de Gálio , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Recidiva Local de Neoplasia , Peptídeos Cíclicos/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Receptores CXCR4/genética
6.
Ann Emerg Med ; 79(2): 187-195, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34607741

RESUMO

STUDY OBJECTIVE: The objective of this study was to describe the proportion of female authors on original research articles and editorials across 4 emergency medicine journals from 2013 to 2019. A secondary objective was to examine the gender composition of middle authors in relation to the genders of their respective first and last authors. METHODS: In this observational study, we selected 4 journals in emergency medicine using the Journal of Citation Reports and prior literature to analyze genders of all authors from research articles and editorials published from January 2013 to September 2019. Reviewers identified author genders through web searches with matching academic qualifications or used a gender identification application programming interface to identify likelihood of male or female identity. The primary outcome was the proportion of female authors in each position. RESULTS: Selected publications included 2,980 original research articles with 18,224 authors (median 6, interquartile range [IQR] 4 to 8) and 433 editorials with 986 authors (median 2, IQR 1 to 2). Women occupied 34.9%, 24.3%, and 36.5% of first, last, and middle author positions on original research articles and 23.8%, 20.5%, and 34.2% of first, last, and middle author positions among editorials, respectively. Publications with female first and last authors (n=340 articles) had a larger proportion of female middle authors (49%, 634/1,290) compared to publications with male first and last authors (n=1667 articles, female middle authors 33% [2,215/6,771]). CONCLUSION: Over the 7 years examined, female authorship in these emergency medicine journals increased. A more pronounced gender gap exists in editorial authorship compared to research articles. On publications where the first and last author were women, a higher proportion of middle authors were women.


Assuntos
Autoria , Bibliometria , Pesquisa Biomédica/tendências , Medicina de Emergência/tendências , Publicações Periódicas como Assunto/tendências , Médicas/tendências , Sexismo/tendências , Feminino , Humanos , Masculino
7.
J Hered ; 113(6): 712-721, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36107789

RESUMO

Sandblossoms, Linanthus parryae is a widespread annual plant species found in washes and sandy open habitats across the Mojave Desert and Eastern Sierra Nevada of California. Studies in this species have played a central role in evolutionary biology, serving as the first test cases of the shifting balance theory of evolution, models of isolation by distance, and metrics to describe the genetic structure of natural populations. Despite the importance of L. parryae in the development of landscape genetics and phylogeography, there are no genomic resources available for the species. Through the California Conservation Genomics Project, we assembled the first genome in the genus Linanthus. Using PacBio HiFi long reads and Hi-C chromatin conformation capture, we assembled 123 scaffolds spanning 1.51 Gb of the 1.96 Gb estimated genome, with a contig N50 of 18.7 Mb and a scaffold N50 of 124.8 Mb. This assembly, with a BUSCO completeness score of 88.7%, will allow us to revisit foundational ideas central to our understanding of how evolutionary forces operate in a geographic landscape. In addition, it will be a new resource to uncover adaptations to arid environments in the fragile desert habitat threatened by urban and solar farm development, climate change, and off-road vehicles.


Assuntos
Adaptação Fisiológica , Genoma , Genômica , Cromossomos
8.
Ophthalmic Plast Reconstr Surg ; 38(3): 263-265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34750317

RESUMO

PURPOSE: To determine the effectiveness of retrobulbar liposomal bupivacaine for controlling postoperative pain following evisceration, compared with 0.75% bupivacaine. METHODS: Randomized controlled trial, in which the postoperative pain scores from 24 patients who had retrobulbar liposomal bupivacaine after an evisceration were compared with the pain scores from 24 patients eviscerated using 0.75% bupivacaine. RESULTS: Patients who received liposomal bupivacaine reported significantly less pain at 24 hours (2.0 out of 10, p = 0.01) and 48 hours (2.2 out of 10, p = 0.01) after surgery than patients who received 0.75% bupivacaine (5.7, and 5.0, respectively). The postoperative pain scores at 1 hour and at 7 days did not significantly differ between the 2 groups. Significantly, fewer patients who received liposomal bupivacaine (0%) than patients who received 0.75% bupivacaine (16.7%) returned emergently during the postoperative period for uncontrolled pain (p ≤ 0.001). CONCLUSIONS: Retrobulbar liposomal bupivacaine is more effective than 0.75% bupivacaine for controlling pain during the first 2 days after evisceration and should be considered for patients undergoing this procedure.


Assuntos
Anestésicos Locais , Bupivacaína , Humanos , Manejo da Dor , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle
9.
Ophthalmic Plast Reconstr Surg ; 38(1): e2-e6, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34431823

RESUMO

An 84-year-old man presented with a localized, firm, tender mass over the right lacrimal sac. He had a history of acute dacryocystitis in the same eye 6 months before presentation, which resolved with antibiotics followed by uneventful dacryocystorhinostomy. At repeat presentation, the patient underwent orbital imaging and excisional biopsy of the lesion. Histologic studies revealed a small cell neuroendocrine carcinoma. The patient was subsequently treated with chemotherapy and radiation. Although there are rare reports of small cell neuroendocrine carcinoma originating in the sino-orbital-lacrimal region, this is the first report of tumor presentation with acute dacryocystitis in a patient with prior dacryocystorhinostomy.


Assuntos
Carcinoma Neuroendócrino , Dacriocistite , Dacriocistorinostomia , Doenças do Aparelho Lacrimal , Ducto Nasolacrimal , Idoso de 80 Anos ou mais , Carcinoma Neuroendócrino/diagnóstico , Dacriocistite/diagnóstico , Dacriocistite/etiologia , Dacriocistite/cirurgia , Humanos , Doenças do Aparelho Lacrimal/cirurgia , Masculino
10.
Genomics ; 113(6): 3762-3773, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34530104

RESUMO

The Pseudomonas putida group comprises strains with biotechnological and clinical relevance. P. alloputida was proposed as a new species and highlighted the misclassification of P. putida. Nevertheless, the population structure of P. alloputida remained unexplored. We retrieved 11,025 Pseudomonas genomes and used P. alloputida Kh7T to delineate the species. The P. alloputida population structure comprises at least 7 clonal complexes (CCs). Clinical isolates are mainly found in CC4 and acquired resistance genes are present at low frequency in plasmids. Virulence profiles support the potential of CC7 members to outcompete other plant or human pathogens through a type VI secretion system. Finally, we found that horizontal gene transfer had an important role in shaping the ability of P. alloputida to bioremediate aromatic compounds such as toluene. Our results provide the grounds to understand P. alloputida genetic diversity and its potential for biotechnological applications.


Assuntos
Transferência Genética Horizontal , Pseudomonas , Humanos , Filogenia , Plasmídeos , Pseudomonas/genética
11.
J Viral Hepat ; 28(3): 517-527, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33306853

RESUMO

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Canadá/epidemiologia , Coinfecção/epidemiologia , Estudos Transversais , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepatite B/complicações , Hepatite B/epidemiologia , Vírus da Hepatite B , Humanos , Recém-Nascido , Masculino , Prevalência
12.
J Viral Hepat ; 28(6): 942-950, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33749086

RESUMO

Tenofovir alafenamide fumarate (TAF) has high plasma stability resulting in fewer renal adverse events compared to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. We aimed to study the effectiveness and renal safety of TAF in a real-world setting, in patients with or without compromised kidney function. CHB patients (Nucleos(t)ide Analogue [NA]-naïve or experienced) who received TAF >1 year from 11 academic institutions as part of the Canadian Hepatitis B Network (CanHepB) were included. Kidney function was measured by estimated glomerular filtration rate (eGFR) as per Cockcroft-Gault. Patients were followed for up to 160 weeks. Of 176 patients receiving TAF, 143 switched from NA (88% TDF), and 33(19%) were NA naïve. Majority of NA-naïve patients (75%) achieved undetectable HBV DNA after one year of TAF treatment. Majority of patients with eGFR <60 mL/min who had renal deterioration during TDF (76%) reversed to eGFR increase after one year of TAF (p=0.009). Among patients with stage 2 chronic kidney disease (CKD) (eGFR 60-89), the estimated eGFR decline during TDF was halted after switching to TAF (p=0.09). NA-experienced patients with abnormal ALT before TAF showed a significant decline after switching to TAF: -0.005 [-0.006 - -0.004] log10 ULN U/L/month, p<0.001). In CHB patients, TAF was safe, well-tolerated and effective in this real-world cohort. Switching to TAF led to improved kidney function, particularly in those with stage 2 CKD, which suggests that the indication for TAF in the guidelines could be extended to patients with an eGFR higher than 60 mL/min.


Assuntos
Hepatite B Crônica , Alanina , Canadá , Fumaratos , Hepatite B Crônica/tratamento farmacológico , Humanos , Rim , Tenofovir/análogos & derivados
13.
Orbit ; 38(4): 269-273, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30125147

RESUMO

Orbital blowout fractures result from trauma which breaks the bony orbital wall while sparing the rim. Previous research into fracture mechanism has focused on bony anatomy. This study evaluates the role of preorbital and intraorbital soft tissue volume in fracture risk. A retrospective case-control study was conducted on 51 cases of adults with unilateral orbital blowout fracture, matched to 51 controls who had experienced orbital trauma by comparable mechanisms without sustaining a fracture. Axial Computed Tomography (CT) images with orbital fine cuts were assessed on a 3D post-processing workstation to measure the volume of the pre- and intraorbital soft tissues, then compared between the two groups using Mann-Whitney U analysis. In the case group, there were 40 males (78%), injured by assault (66%), fall (12%), motor vehicle collision (10%), or other cause (12%). The control group included 33 males (65%), injured by assault (55%), fall (22%), motor vehicle (4%), or other cause (20%). There was no significant difference in mechanism rates between case and control groups. Median preorbital volumes were 12.5 cm3 in the case group and14.1 cm3 in controls (p = 0.02). Median intraorbital volumes were 24.4 cm3 in the case group and 25.9 cm3 in controls (p = 0.003). CT volumetric analysis shows that patients who sustained blowout fractures have lower preorbital and intraorbital soft tissue volume than those who did not fracture. This underscores the significant role that soft tissues play in dissipating impact forces, both anterior to the orbital rim and within the orbit itself.


Assuntos
Órbita/diagnóstico por imagem , Fraturas Orbitárias/diagnóstico por imagem , Fraturas Orbitárias/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X , População Urbana/estatística & dados numéricos , Adulto Jovem
14.
Mol Ecol ; 27(10): 2397-2413, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29701315

RESUMO

Using multiple, independent approaches to molecular species delimitation is advocated to accommodate limitations and assumptions of a single approach. Incongruence in delimitation schemes is a potential by-product of employing multiple methods on the same data, and little attention has been paid to its reconciliation. Instead, a particular scheme is prioritized, and/or molecular delimitations are coupled with additional, independent lines of evidence that mitigate incongruence. We advocate that incongruence within a line of evidence should be accounted for before comparing across lines of evidence that can themselves be incongruent. Additionally, it is not uncommon for empiricists working in nonmodel systems to be data-limited, generating some concern for the adequacy of available data to address the question of interest. With conservation and management decisions often hinging on the status of species, it seems prudent to understand the capabilities of approaches we use given the data we have. Here, we apply two molecular species delimitation approaches, spedeSTEM and BPP, to the Castilleja ambigua (Orobanchaceae) species complex, a relatively young plant lineage in western North America. Upon finding incongruence in our delimitation, we employed a post hoc simulation study to examine the power of these approaches to delimit species. Given the data we collected, we find that spedeSTEM lacks the power to delimit while BPP is capable, thus allowing us to address incongruence before proceeding in delimitation. We suggest post hoc simulation studies like this compliment empirical delimitation and serve as a means of exploring conflict within a line of evidence and dealing with it appropriately.


Assuntos
Especiação Genética , Orobanchaceae/genética , Cloroplastos/genética , Simulação por Computador , Funções Verossimilhança , Orobanchaceae/classificação , Filogenia , Especificidade da Espécie
15.
Ophthalmology ; 125(7): 1100-1108, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29551422

RESUMO

PURPOSE: Severe vision loss is a risk of orbital surgery which physicians should counsel patients about, but the overall risk rate is unknown. This research was conducted to determine the risk of severe vision loss related to orbital surgery. DESIGN: Retrospective review. PARTICIPANTS: Patients who underwent orbital surgery at either of 2 academic medical centers between January 1994 and December 2014. METHODS: A billing database search was conducted to identify all patients who had orbital surgery during the study period, cross-checked against diagnostic codes related to vision loss. Charts were screened to determine baseline demographic and medical history, surgical procedure, intraoperative and perioperative management, and visual acuity. Patients with preoperative visual acuity ≥20/200 that worsened ≤20/400 after orbital surgery were included for detailed review. Statistical analysis was conducted to identify factors posing particular risk or benefit to visual outcome in these patients. MAIN OUTCOME MEASURES: Visual acuity after orbital surgery. RESULTS: A total of 1665 patients underwent orbital surgery during the inclusion period, with 14 patients sustaining severe vision loss ranging from counting fingers at 1 foot to no light perception (overall risk, 0.84%). The causes of vision loss included retrobulbar hemorrhage, malpositioned implant, optic nerve ischemia, or direct optic nerve insult. When stratified by surgical approach, the risk of a blinding surgical complication was significantly higher for patients undergoing orbital floor repair in the setting of multiple facial fractures (subgroup risk, 6.45%), bony decompression of the optic canal (subgroup risk, 15.6%), or intracranial approach to the orbital roof (subgroup risk, 18.2%). Seven of 8 patients with a potentially reversible cause of postoperative vision loss underwent urgent repeat surgery, and 2 regained substantial vision (20/20 and 20/25). Administration of intravenous corticosteroids had no significant effect on visual acuity outcome. CONCLUSIONS: The overall risk of severe vision loss after orbital surgery is 0.84%. The subgroup risk is higher in patients undergoing facial polytrauma repair, optic canal decompression, or orbital apex surgery from an intracranial approach. Close postoperative monitoring and urgent assessment and management of acute vision loss may improve visual outcome in some patients.


Assuntos
Cegueira/epidemiologia , Cegueira/terapia , Procedimentos Cirúrgicos Oftalmológicos , Órbita/cirurgia , Fraturas Orbitárias/cirurgia , Complicações Pós-Operatórias , Adulto , Idoso , Descompressão Cirúrgica , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Fatores de Risco , Acuidade Visual/fisiologia
16.
Nat Rev Neurosci ; 14(10): 722-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23985834

RESUMO

The extracellular matrix (ECM) occupies a notable proportion of the CNS and contributes to its normal physiology. Alterations to the ECM occur after neural injury (for example, in multiple sclerosis, spinal cord injury or Alzheimer's disease) and can have drastic consequences. Of note, injury-induced changes in chondroitin sulphate proteoglycans (CSPGs)--a family of ECM proteoglycans--can lead to the inhibition of myelin repair. Here, we highlight the pathophysiological roles of the brain's ECM, particularly those of CSPGs, after neural insults and discuss how the ECM can be targeted to promote remyelination.


Assuntos
Encéfalo/metabolismo , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/fisiopatologia , Matriz Extracelular/metabolismo , Regeneração Nervosa/fisiologia , Animais , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Humanos
17.
Proc Natl Acad Sci U S A ; 112(31): E4306-15, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26199418

RESUMO

Infection of cells with DNA viruses triggers innate immune responses mediated by DNA sensors. cGMP-AMP synthase (cGAS) is a key DNA sensor that produces the cyclic dinucleotide cGMP-AMP (cGAMP) upon activation, which binds to and activates stimulator of interferon genes (STING), leading to IFN production and an antiviral response. Kaposi's sarcoma-associated herpesvirus (KSHV) is a DNA virus that is linked to several human malignancies. We report that KSHV infection activates the cGAS-STING pathway, and that cGAS and STING also play an important role in regulating KSHV reactivation from latency. We screened KSHV proteins for their ability to inhibit this pathway and identified six viral proteins that block IFN-ß activation through this pathway. This study is the first report identifying multiple viral proteins encoded by a human DNA virus that inhibit the cGAS-STING DNA sensing pathway. One such protein, viral interferon regulatory factor 1 (vIRF1), targets STING by preventing it from interacting with TANK binding kinase 1 (TBK1), thereby inhibiting STING's phosphorylation and concomitant activation, resulting in an inhibition of the DNA sensing pathway. Our data provide a unique mechanism for the negative regulation of STING-mediated DNA sensing. Moreover, the depletion of vIRF1 in the context of KSHV infection prevented efficient viral reactivation and replication, and increased the host IFN response to KSHV. The vIRF1-expressing cells also inhibited IFN-ß production following infection with DNA pathogens. Collectively, our results demonstrate that gammaherpesviruses encode inhibitors that block cGAS-STING-mediated antiviral immunity, and that modulation of this pathway is important for viral transmission and the lifelong persistence of herpesviruses in the human population.


Assuntos
DNA Viral/metabolismo , Herpesvirus Humano 8/fisiologia , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Sequência de Bases , DNA Viral/genética , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fator Regulador 1 de Interferon/metabolismo , Interferon beta/metabolismo , Dados de Sequência Molecular , Motivos de Nucleotídeos/genética , Fases de Leitura Aberta/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Virais/metabolismo , Ativação Viral , Latência Viral
18.
J Aquat Anim Health ; 30(3): 201-209, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29799641

RESUMO

In response to population declines of North American Burbot Lota lota maculosa (hereafter, Burbot), conservation aquaculture methods have been developed for this species. In general, Burbot are relatively resistant to many salmonid pathogens; however, cultured juvenile Burbot have experienced periodic epizootic disease outbreaks during production. A series of trials was conducted to determine the virulence of select bacteria isolated from juvenile Burbot after outbreaks that occurred in 2012 and 2013 at the University of Idaho's Aquaculture Research Institute. Initial clinical diagnostics and sampling resulted in the isolation of numerous putative bacterial pathogens. To determine which bacteria were the most likely causative agents contributing to these epizootics, juvenile Burbot received intraperitoneal (IP) injections of select bacteria in log-phase growth. Mortality associated with specific isolates was recorded, and more comprehensive challenges followed this initial screening. These challenges used side-by-side IP and immersion methods to expose Burbot to potential pathogens. The challenges resulted in significantly higher mortalities in fish after IP injection with two Aeromonas sp. isolates compared to controls, but no significant difference in mortality for immersion-challenged groups was observed. Results demonstrate that two Aeromonas sp. isolates cultured from the epizootics are virulent to Burbot.


Assuntos
Aeromonas/fisiologia , Aeromonas/patogenicidade , Doenças dos Peixes/microbiologia , Gadiformes , Infecções por Bactérias Gram-Negativas/veterinária , Aeromonas/isolamento & purificação , Animais , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Doenças dos Peixes/epidemiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia
19.
J Craniofac Surg ; 28(2): 379-382, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28005648

RESUMO

PURPOSE: To compare exophthalmos reduction in lateral orbital decompressions performed via rim sparing versus temporary rim removal techniques. METHODS: The authors performed a retrospective chart review of all patients who underwent simple lateral or combined medial and lateral wall orbital decompression between 2005 and 2013 by a single surgeon. Nineteen patients (33 orbits) were identified for inclusion in the study. Decompression procedures (1 or 2 orbital walls) involved either a rim sparing or a temporary rim removal technique. Preoperatively, all patients had stable exophthalmos defined as ≤1 mm change in exophthalmos over 2 consecutive visits. Measurements were taken again at the 3 to 4 months postoperative visit. Exclusion criteria were acute or unstable exophthalmos, exophthalmos secondary to malignancy, and patients lost to follow up. RESULTS: There were no significant differences in exophthalmos reduction for rim sparing versus temporary rim removal techniques in any of the groups studied. Simple lateral decompression procedures achieved 3.7 and 4.4 mm of exophthalmos reduction in rim sparing versus temporary rim removal techniques, respectively (P = 0.49). Exophthalmos reduction in combined medial and lateral wall orbital decompression was 4.1 mm for rim sparing and 3.5 mm for temporary rim removal techniques (P = 0.75). CONCLUSION: In our experience, orbital decompression approached through rim sparing or temporary rim removal techniques achieves similar results in simple lateral and combined medial and lateral decompressions. Though these techniques generate similar outcomes, temporary rim removal provides for improved visibility and access to deep orbital structures.


Assuntos
Descompressão Cirúrgica/métodos , Exoftalmia/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Órbita/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
20.
J Virol ; 89(22): 11572-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26355087

RESUMO

UNLABELLED: Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus known to establish lifelong latency in the human host. We and others have previously shown that three KSHV homologs of cellular interferon regulatory factors (IRFs), known as viral IRFs (vIRFs), participate in evasion of the host interferon (IFN) response. We report that vIRF1 interacts with the cellular interferon-stimulated gene 15 (ISG15) E3 ligase, HERC5, in the context of Toll-like receptor 3 (TLR3) activation and IFN induction. The ISG15 protein is covalently conjugated to target proteins upon activation of the interferon response. Interaction between vIRF1 and HERC5 was confirmed by immunoprecipitation, and the region between amino acids 224 and 349 of vIRF1 was required for interaction with HERC5. We further report that expression of vIRF1 in the context of TLR3 activation results in decreased ISG15 conjugation of proteins. Specifically, TLR3-induced ISG15 conjugation and protein levels of cellular IRF3, a known ISG15 target, were decreased in the presence of vIRF1 compared to the control. vIRF1 itself was also identified as a target of ISG15 conjugation. KSHV-infected cells exhibited increased ISG15 conjugation upon reactivation from latency in coordination with increased IFN. Furthermore, knockdown of ISG15 in latently infected cells resulted in a higher level of KSHV reactivation and an increase in infectious virus. These data suggest that the KSHV vIRF1 protein affects ISG15 conjugation and interferon responses and may contribute to effective KSHV replication. IMPORTANCE: The KSHV vIRF1 protein can inhibit interferon activation in response to viral infection. We identified a cellular protein named HERC5, which is the major ligase for ISG15, as a vIRF1 binding partner. vIRF1 association with HERC5 altered ISG15 modification of cellular proteins, and knockdown of ISG15 augmented reactivation of KSHV from latency.


Assuntos
Citocinas/metabolismo , Herpesvirus Humano 8/fisiologia , Fatores Reguladores de Interferon/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptor 3 Toll-Like/metabolismo , Ubiquitinas/metabolismo , Proteínas Virais/metabolismo , Ativação Viral , Sequência de Aminoácidos , Citocinas/genética , Ativação Enzimática , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Interferência de RNA , RNA Interferente Pequeno , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/genética , Latência Viral , Replicação Viral
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