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1.
bioRxiv ; 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38659890

RESUMO

During chronic infections and tumor progression, CD8 T cells gradually lose their effector functions and become exhausted. These exhausted CD8 T cells are heterogeneous and comprised of different subsets, including self-renewing progenitors that give rise to Ly108 - CX3CR1 + effector-like cells. Generation of these effector-like cells is essential for the control of chronic infections and tumors, albeit limited. However, the precise cues and mechanisms directing the formation and maintenance of exhausted effector-like are incompletely understood. Using genetic mouse models challenged with LCMV Clone 13 or syngeneic tumors, we show that the expression of a transcriptional repressor, growth factor independent 1 (Gfi1) is dynamically regulated in exhausted CD8 T cells, which in turn regulates the formation of exhausted effector-like cells. Gfi1 deletion in T cells dysregulates the chromatin accessibility and transcriptomic programs associated with the differentiation of LCMV Clone 13-specific CD8 T cell exhaustion, preventing the formation of effector-like and terminally exhausted cells while maintaining progenitors and a newly identified Ly108 + CX3CR1 + state. These Ly108 + CX3CR1 + cells have a distinct chromatin profile and may represent an alternative target for therapeutic interventions to combat chronic infections and cancer. In sum, we show that Gfi1 is a critical regulator of the formation of exhausted effector-like cells.

2.
Sci Rep ; 12(1): 14087, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982220

RESUMO

Immune checkpoint blockade (ICB) leads to durable and complete tumour regression in some patients but in others gives temporary, partial or no response. Accordingly, significant efforts are underway to identify tumour-intrinsic mechanisms underlying ICB resistance. Results from a published CRISPR screen in a mouse model suggested that targeting STUB1, an E3 ligase involved in protein homeostasis, may overcome ICB resistance but the molecular basis of this effect remains unclear. Herein, we report an under-appreciated role of STUB1 to dampen the interferon gamma (IFNγ) response. Genetic deletion of STUB1 increased IFNGR1 abundance on the cell surface and thus enhanced the downstream IFNγ response as showed by multiple approaches including Western blotting, flow cytometry, qPCR, phospho-STAT1 assay, immunopeptidomics, proteomics, and gene expression profiling. Human prostate and breast cancer cells with STUB1 deletion were also susceptible to cytokine-induced growth inhibition. Furthermore, blockade of STUB1 protein function recapitulated the STUB1-null phenotypes. Despite these encouraging in vitro data and positive implications from clinical datasets, we did not observe in vivo benefits of inactivating Stub1 in mouse syngeneic tumour models-with or without combination with anti-PD-1 therapy. However, our findings elucidate STUB1 as a barrier to IFNγ sensing, prompting further investigations to assess if broader inactivation of human STUB1 in both tumors and immune cells could overcome ICB resistance.


Assuntos
Interferon gama , Neoplasias , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Interferon gama/metabolismo , Interferon gama/farmacologia , Espaço Intracelular/metabolismo , Masculino , Camundongos , Ligação Proteica , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
3.
Nat Genet ; 54(7): 963-975, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35773407

RESUMO

The consensus molecular subtype (CMS) classification of colorectal cancer is based on bulk transcriptomics. The underlying epithelial cell diversity remains unclear. We analyzed 373,058 single-cell transcriptomes from 63 patients, focusing on 49,155 epithelial cells. We identified a pervasive genetic and transcriptomic dichotomy of malignant cells, based on distinct gene expression, DNA copy number and gene regulatory network. We recapitulated these subtypes in bulk transcriptomes from 3,614 patients. The two intrinsic subtypes, iCMS2 and iCMS3, refine CMS. iCMS3 comprises microsatellite unstable (MSI-H) cancers and one-third of microsatellite-stable (MSS) tumors. iCMS3 MSS cancers are transcriptomically more similar to MSI-H cancers than to other MSS cancers. CMS4 cancers had either iCMS2 or iCMS3 epithelium; the latter had the worst prognosis. We defined the intrinsic epithelial axis of colorectal cancer and propose a refined 'IMF' classification with five subtypes, combining intrinsic epithelial subtype (I), microsatellite instability status (M) and fibrosis (F).


Assuntos
Neoplasias Colorretais , Neoplasias Epiteliais e Glandulares , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Epiteliais/patologia , Humanos , Instabilidade de Microssatélites , Repetições de Microssatélites/genética , Neoplasias Epiteliais e Glandulares/genética , Transcriptoma/genética
4.
Sci Rep ; 11(1): 16791, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408232

RESUMO

Dietary niche is fundamental for determining species ecology; thus, a detailed understanding of what drives variation in dietary niche is vital for predicting ecological shifts and could have implications for species management. Gut microbiota can be important for determining an organism's dietary preference, and therefore which food resources they are likely to exploit. Evidence for whether the composition of the gut microbiota is plastic in response to changes in diet is mixed. Also, the extent to which dietary preference can be changed following colonisation by new gut microbiota from different species is unknown. Here, we use Drosophila spp. to show that: (1) the composition of an individual's gut microbiota can change in response to dietary changes, and (2) ingestion of foreign gut microbes can cause individuals to be attracted to food types they previously had a strong aversion to. Thus, we expose a mechanism for facilitating rapid shifts in dietary niche over short evolutionary timescales.


Assuntos
Dieta , Gorduras Insaturadas na Dieta/farmacologia , Fibras na Dieta/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Drosophila/metabolismo , Drosophila/microbiologia , Fezes/microbiologia
5.
Sci Rep ; 11(1): 4435, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627690

RESUMO

Aberrant miRNA expression has been associated with many diseases, and extracellular miRNAs that circulate in the bloodstream are remarkably stable. Recently, there has been growing interest in identifying cell-free circulating miRNAs that can serve as non-invasive biomarkers for early detection of disease or selection of treatment options. However, quantifying miRNA levels in biofluids is technically challenging due to their low abundance. Using reference samples, we performed a cross-platform evaluation in which miRNA profiling was performed on four different qPCR platforms (MiRXES, Qiagen, Applied Biosystems, Exiqon), nCounter technology (NanoString), and miRNA-Seq. Overall, our results suggest that using miRNA-Seq for discovery and targeted qPCR for validation is a rational strategy for miRNA biomarker development in clinical samples that involve limited amounts of biofluids.


Assuntos
Biomarcadores/metabolismo , Líquidos Corporais/metabolismo , MicroRNA Circulante/genética , Nanotecnologia/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Linhagem Celular , Perfilação da Expressão Gênica/métodos , Técnicas Genéticas , Células HEK293 , Humanos , Células THP-1
6.
Front Genet ; 11: 1036, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133138

RESUMO

Novel targeted agents to inhibit DNA repair pathways to sensitize tumors to irradiation (IR) are being investigated as an alternative to chemoradiation for locally advanced human papilloma virus negative (HPV-negative) head and neck squamous cell carcinoma (HNSCC). Two well-characterized targets that, when inhibited, exhibit potent IR sensitization are PARP1 and DNA-PKcs. However, their cooperation in sensitizing HPV-negative HNSCC to IR remains to be explored given that PARP1 and DNA-Pk CS bind to unresected stalled DNA replication forks and cooperate to recruit XRCC1 to facilitate double-strand break repair. Here, we show that the combination of the DNA-PK inhibitor NU7441 and the PARP inhibitor olaparib significantly decrease proliferation (61-78%) compared to no reduction with either agent alone (p < 0.001) in both SCC1 and SCC6 cell lines. Adding IR to the combination further decreased cell proliferation (91-92%, p < 0.001) in SCC1 and SCC6. Similar results were observed using long-term colony formation assays [dose enhancement ratio (DER) 2.3-3.2 at 4Gy, p < 0.05]. Reduced cell survival was attributed to increased apoptosis and G2/M cell cycle arrest. Kinomic analysis using tyrosine (PTK) and serine/threonine (STK) arrays reveals that combination treatment results in the most potent inhibition of kinases involved in the CDK and ERK pathways compared to either agent alone. In vivo, a significant delay of tumor growth was observed in UM-SCC1 xenografts receiving IR with olaparib and/or NU7441, which was similar to the cisplatin-IR group. Both regimens were less toxic than cisplatin-IR as assessed by loss of mouse body weight. Taken together, these results demonstrate that the combination of NU7441 and olaparib with IR enhances HPV-negative HNSCC inhibition in both cell culture and in mice, suggesting a potential innovative combination for effectively treating patients with HPV-negative HNSCC.

7.
J Food Sci ; 84(12): 3437-3444, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31762045

RESUMO

Tokaj wines (Hungaricum) are botrytized wines acknowledged for the unique organoleptic properties bestowed by botrytized grape berries during production. Excluding these berries during wine production or manipulating the sugar content of low-grade wines to imitate high-grade wines are some recent suspicious activities that threaten the wine quality. Advanced methods such as spectroscopy and sensor-based devices have been lauded for rapid, reliable, and cost-effective analysis, but there has been no report of their application to monitor grape must concentrate adulteration in botrytized wines. The study aimed to develop models to rapidly discriminate lower grade Tokaj wines, "Forditas I" and "Forditas II," that were artificially adulterated with grape must concentrate to match the sugar content of high-grade Tokaj wines using an electronic tongue (e-tongue) and two near infrared spectrometers (NIRS). Data were evaluated with the following chemometrics: principal component analysis (PCA), discriminant analysis (LDA), partial least square regression (PLSR), and aquaphotomics (a novel approach). There was a noticeable pattern of separation in PCA for all three instruments and 100% classification of adulterated and nonadulterated wines in LDA using the e-tongue. Aquagrams from the aquaphotomics approach showed important water absorption bands capable of being markers of Tokaj wine quality. PLSR models showed coefficient of determination (R2 CV) of 0.98 (e-tongue), 0.97 (benchtop NIRS), 0.87 (handheld NIRS), and low root mean squared errors of cross-validation. All three instruments could discriminate, classify, and predict grape must concentrate adulteration in Tokaj with a high accuracy and low error. The methods can be applied for routine quality checks of botrytized wines. PRACTICAL APPLICATION: Tokaj wines (Hungaricum) are botrytized wines acknowledged for the unique organoleptic properties bestowed by botrytized grape berries during production. Excluding these berries during wine production or manipulating the sugar content of low-grade wines to imitate high-grade wines are some recent suspicious activities that threaten the wine quality. Using advanced instruments, the electronic tongue, benchtop near infrared spectroscopy, and a handheld near infrared spectroscopy, we could discriminate, classify, and predict grape must concentrate adulteration in Tokaj with a high accuracy and low error. The models in our study can be applied for routine quality checks of botrytized wines.


Assuntos
Nariz Eletrônico , Espectrofotometria Infravermelho/métodos , Vinho/análise , Análise Discriminante , Frutas/química , Análise dos Mínimos Quadrados , Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho , Vitis/química
8.
BMC Cancer ; 18(1): 490, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703161

RESUMO

BACKGROUND: Melanoma brain metastasis is associated with an extremely poor prognosis, with a median overall survival of 4-5 months. Since 2011, the overall survival of patients with stage IV melanoma has been significantly improved with the advent of new targeted therapies and checkpoint inhibitors. We analyze the survival outcomes of patients diagnosed with brain metastasis after the introduction of these novel drugs. METHODS: We performed a retrospective analysis of our melanoma center database and identified 79 patients with brain metastasis between 2011 and 2015. RESULTS: The median time from primary melanoma diagnosis to brain metastasis was 3.2 years. The median overall survival duration from the time of initial brain metastasis was 12.8 months. Following a diagnosis of brain metastasis, 39 (49.4%), 28 (35.4%), and 24 (30.4%) patients were treated with anti-CTLA-4 antibody, anti-PD-1 antibody, or BRAF inhibitors (with or without a MEK inhibitor), with a median overall survival of 19.2 months, 37.9 months and 12.7 months, respectively. Factors associated with significantly reduced overall survival included male sex, cerebellar metastasis, higher number of brain lesions, and treatment with whole-brain radiation therapy. Factors associated with significantly longer overall survival included treatment with craniotomy, stereotactic radiosurgery, or with anti-PD-1 antibody after initial diagnosis of brain metastasis. CONCLUSIONS: These results show a significant improvement in the overall survival of patients with melanoma brain metastasis in the era of novel therapies. In addition, they suggest the activity of anti-PD-1 therapy specifically in the setting of brain metastasis.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Melanoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Antígeno CTLA-4/antagonistas & inibidores , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Future Sci OA ; 3(4): FSO244, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29134128

RESUMO

AIM: Expression of PD-L1 in the tumor is associated with more favorable responses to anti-PD-1 therapy in multiple cancers. However, obtaining tumor biopsies for PD-L1 interrogation is an invasive procedure and challenging to assess repeatedly as the disease progresses. MATERIALS & METHODS: Here we assess an alternative, minimally invasive approach to analyze blood samples for circulating tumor cells (CTCs) that have broken away from the tumor and entered the periphery. Our approach uses sized-based microfluidic CTC enrichment and subsequent characterization with microfluidic-based cytometry (chipcytometry). CONCLUSION: We demonstrate tumor-cell detection and characterization for PD-L1, and other markers, in both spiked and patient samples. This preliminary communication is the first report using chipcytometry for the characterization of CTCs.

10.
BMC Genomics ; 18(1): 829, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29078745

RESUMO

BACKGROUND: Viral populations are complex, dynamic, and fast evolving. The evolution of groups of closely related viruses in a competitive environment is termed quasispecies. To fully understand the role that quasispecies play in viral evolution, characterizing the trajectories of viral genotypes in an evolving population is the key. In particular, long-range haplotype information for thousands of individual viruses is critical; yet generating this information is non-trivial. Popular deep sequencing methods generate relatively short reads that do not preserve linkage information, while third generation sequencing methods have higher error rates that make detection of low frequency mutations a bioinformatics challenge. Here we applied BAsE-Seq, an Illumina-based single-virion sequencing technology, to eight samples from four chronic hepatitis B (CHB) patients - once before antiviral treatment and once after viral rebound due to resistance. RESULTS: With single-virion sequencing, we obtained 248-8796 single-virion sequences per sample, which allowed us to find evidence for both hard and soft selective sweeps. We were able to reconstruct population demographic history that was independently verified by clinically collected data. We further verified four of the samples independently through PacBio SMRT and Illumina Pooled deep sequencing. CONCLUSIONS: Overall, we showed that single-virion sequencing yields insight into viral evolution and population dynamics in an efficient and high throughput manner. We believe that single-virion sequencing is widely applicable to the study of viral evolution in the context of drug resistance and host adaptation, allows differentiation between soft or hard selective sweeps, and may be useful in the reconstruction of intra-host viral population demographic history.


Assuntos
Evolução Molecular , Genoma Viral , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B/virologia , Lamivudina/farmacologia , Vírion/genética , Alelos , Substituição de Aminoácidos , Biologia Computacional/métodos , Código de Barras de DNA Taxonômico , Farmacorresistência Viral/efeitos dos fármacos , Frequência do Gene , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/isolamento & purificação , Humanos , Lamivudina/uso terapêutico , Mutação
11.
World Neurosurg ; 103: 951.e5-951.e12, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28433840

RESUMO

BACKGROUND: We describe a rare case of a sphenoid sinus myxoma that was resected via an endoscopic endonasal skull base approach. We review the literature regarding these rare tumors of the paranasal sinuses. CASE DESCRIPTION: A 72-year-old woman was diagnosed with an incidental sphenoid sinus tumor and left sphenoid wing meningioma during a workup for left-sided proptosis and diplopia. Biopsies of the sphenoid wing and sphenoid sinus tumors were obtained. After undergoing surgical resection of the meningioma, the patient then underwent definitive resection of the sphenoid sinus myxoma via endoscopic endonasal skull base approach. Postoperative imaging demonstrated a gross total resection. The patient suffered postoperative thromboembolic complications due to underlying hypercoagulable state but made a complete recovery and returned to her neurologic baseline. There has been no evidence of recurrent myxoma in the sphenoid sinus 24 months after surgery. DISCUSSION: Myxomas are benign tumors derived from primitive mesenchyme. Myxomas very rarely present in the paranasal or skull base location. Complete surgical resection is the primary treatment for these tumors. The endoscopic endonasal approach is an effective technique for resecting various benign and more aggressive extradural skull base tumors. CONCLUSIONS: Myxomas of the sphenoid sinus are rare. The endoscopic endonasal skull base approach is an effective and minimal access technique for resection of this rare tumor of the sphenoid sinus.


Assuntos
Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Mixoma/diagnóstico por imagem , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Seio Esfenoidal/diagnóstico por imagem , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Mixoma/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias dos Seios Paranasais/cirurgia , Osso Esfenoide/cirurgia , Seio Esfenoidal/cirurgia
12.
Nat Med ; 23(5): 551-555, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28346412

RESUMO

To date, anti-CTLA-4 (ipilimumab) or anti-PD-1 (nivolumab) monotherapy has not been demonstrated to be of substantial clinical benefit in patients with prostate cancer. To identify additional immune-inhibitory pathways in the prostate-tumor microenvironment, we evaluated untreated and ipilimumab-treated tumors from patients in a presurgical clinical trial. Levels of the PD-L1 and VISTA inhibitory molecules increased on independent subsets of macrophages in treated tumors. Our data suggest that VISTA represents another compensatory inhibitory pathway in prostate tumors after ipilimumab therapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Antígenos B7/metabolismo , Antígeno B7-H1/metabolismo , Macrófagos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/imunologia , Adenocarcinoma/metabolismo , Adulto , Idoso , Animais , Antígenos B7/imunologia , Antígeno B7-H1/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Ipilimumab , Macrófagos/imunologia , Masculino , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Prostatectomia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Linfócitos T , Análise Serial de Tecidos
13.
Int J Mol Sci ; 17(9)2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27657050

RESUMO

In cancer drug discovery, it is important to investigate the genetic determinants of response or resistance to cancer therapy as well as factors that contribute to adverse events in the course of clinical trials. Despite the emergence of new technologies and the ability to measure more diverse analytes (e.g., circulating tumor cell (CTC), circulating tumor DNA (ctDNA), etc.), tumor tissue is still the most common and reliable source for biomarker investigation. Because of its worldwide use and ability to preserve samples for many decades at ambient temperature, formalin-fixed, paraffin-embedded tumor tissue (FFPE) is likely to be the preferred choice for tissue preservation in clinical practice for the foreseeable future. Multiple analyses are routinely performed on the same FFPE samples (such as Immunohistochemistry (IHC), in situ hybridization, RNAseq, DNAseq, TILseq, Methyl-Seq, etc.). Thus, specimen prioritization and optimization of the isolation of analytes is critical to ensure successful completion of each assay. FFPE is notorious for producing suboptimal DNA quality and low DNA yield. However, commercial vendors tend to request higher DNA sample mass than what is actually required for downstream assays, which restricts the breadth of biomarker work that can be performed. We evaluated multiple genomics service laboratories to assess the current state of NGS pre-analytical processing of FFPE. Significant differences in pre-analytical capabilities were observed. Key aspects are highlighted and recommendations are made to improve the current practice in translational research.

14.
Interv Neuroradiol ; 22(4): 457-65, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27020696

RESUMO

OBJECTIVE: The existing literature regarding preoperative cervical spinal tumor embolization is sparse, with few discussions on the indications, risks, and best techniques. We present our experience with the preoperative endovascular management of hypervascular cervical spinal tumors. METHODS: We performed a retrospective review of all patients who underwent preoperative spinal angiography (regardless of whether tumor embolization was performed) at our institution (from 2002 to 2012) for primary and metastatic cervical spinal tumors. Tumor vascularity was graded from 0 (tumor blush equal to the normal adjacent vertebral body) to 3 (intense tumor blush with arteriovenous shunting). Tumors were considered "hypervascular" if they had a tumor vascular grade from 1 to 3. Embolic materials included particles, liquid embolics, and detachable coils. The main embolization technique was superselective catheterization of an arterial tumor feeder followed by injection of embolic material. This technique could be used alone or supplemented with occlusion of dangerous anastomoses of the vertebral artery as needed to prevent inadvertent embolization of the vertebrobasilar system. In cases when superselective catheterization of the tumoral feeder was not feasible, embolization was performed from a proximal catheter position after occlusion of branches supplying areas other than the tumor ("flow diversion"). RESULTS: A total of 47 patients with 49 cervical spinal tumors were included in this study. Of the 49 total tumors, 41 demonstrated increased vascularity (vascularity score > 0). The most common tumor pathology in our series was renal cell carcinoma (RCC) (N = 16; 32.7% of all tumors) followed by thyroid carcinoma (N = 7; 14.3% of all tumors).Tumor embolization was undertaken in 25 hypervascular tumors resulting in complete, near-complete, and partial embolization in 36.0% (N = 9), 44.0% (N = 11), and 20.0% (N = 5) of embolized tumors, respectively. We embolized 42 tumor feeders in 25 tumors. The most commonly embolized tumor feeders were branches of the vertebral artery (19.0%; N = 8), the deep cervical artery (19.0%; N = 8), and the ascending cervical artery (19.0%; N = 8). Sixteen hypervascular tumors were not embolized because of minimal hypervascularity (8/16), unacceptably high risk of spinal cord or vertebrobasilar ischemia (4/16), failed superselective catheterization of tumor feeder (3/16), and cancellation of surgery (1/16). Vertebral artery occlusion was performed in 20% of embolizations. There were no new post-procedure neurological deficits or any serious adverse events. Estimated blood loss data from this cohort show a significant decrease in operative blood loss for embolized tumors of moderate and significant hypervascularity. CONCLUSIONS: Preoperative embolization of cervical spinal tumors can be performed safely and effectively in centers with significant experience and a standardized approach.


Assuntos
Embolização Terapêutica/métodos , Neoplasias da Coluna Vertebral/terapia , Adolescente , Adulto , Idoso , Angiografia , Vértebras Cervicais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Cuidados Pré-Operatórios , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/cirurgia , Resultado do Tratamento
15.
PLoS One ; 10(7): e0134408, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221963

RESUMO

PURPOSE: The National Comprehensive Cancer Network (NCCN) has proposed guidelines for the genetic testing of the BRCA1 and BRCA2 genes, based on studies in western populations. This current study assessed potential predictive factors for BRCA mutation probability, in an Asian population. METHODS: A total of 359 breast cancer patients, who presented with either a family history (FH) of breast and/or ovarian cancer or early onset breast cancer, were accrued at the National Cancer Center Singapore (NCCS). The relationships between clinico-pathological features and mutational status were calculated using the Chi-squared test and binary logistic regression analysis. RESULTS: Of 359 patients, 45 (12.5%) had deleterious or damaging missense mutations in BRCA1 and/or BRCA2. BRCA1 mutations were more likely to be found in ER-negative than ER-positive breast cancer patients (P=0.01). Moreover, ER-negative patients with BRCA mutations were diagnosed at an earlier age (40 vs. 48 years, P=0.008). Similarly, triple-negative breast cancer (TNBC) patients were more likely to have BRCA1 mutations (P=0.001) and that these patients were diagnosed at a relatively younger age than non-TNBC patients (38 vs. 46 years, P=0.028). Our analysis has confirmed that ER-negative status, TNBC status and a FH of hereditary breast and ovarian cancer (HBOC) are strong factors predicting the likelihood of having BRCA mutations. CONCLUSIONS: Our study provides evidence that TNBC or ER-negative patients may benefit from BRCA genetic testing, particularly younger patients (<40 years) or those with a strong FH of HBOC, in Asian patients.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Testes Genéticos/métodos , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Distribuição de Qui-Quadrado , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/estatística & dados numéricos , Feminino , Testes Genéticos/estatística & dados numéricos , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Valor Preditivo dos Testes , Receptores de Estrogênio/metabolismo , Fatores de Risco , Singapura , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Adulto Jovem
16.
Heredity (Edinb) ; 114(6): 539-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25649504

RESUMO

Maternally inherited symbionts are common in arthropods and many have important roles in host adaptation. The observation that specific symbiont lineages infect distantly related host species implies new interactions are commonly established by lateral transfer events. However, studies have shown that symbionts often perform poorly in novel hosts. We hypothesized selection on the symbiont may be sufficiently rapid that poor performance in a novel host environment is rapidly ameliorated, permitting symbiont maintenance. Here, we test this prediction for a Spiroplasma strain transinfected into the novel host Drosophila melanogaster. In the generations immediately following transinfection, the symbiont had low transmission efficiency to offspring and imposed severe fitness costs on its host. We observed that effects on host fitness evolved rapidly, being undetectable after 17 generations in the novel host, whereas vertical transmission efficiency was poorly responsive over this period. Our results suggest that long-term symbiosis may more readily be established in cases where symbionts perform poorly in just one aspect of symbiosis.


Assuntos
Adaptação Biológica , Evolução Biológica , Drosophila melanogaster/microbiologia , Spiroplasma/fisiologia , Simbiose , Animais , Feminino , Aptidão Genética , Modelos Lineares , Masculino
17.
Genome Biol ; 15(11): 517, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25406369

RESUMO

We present a method for obtaining long haplotypes, of over 3 kb in length, using a short-read sequencer, Barcode-directed Assembly for Extra-long Sequences (BAsE-Seq). BAsE-Seq relies on transposing a template-specific barcode onto random segments of the template molecule and assembling the barcoded short reads into complete haplotypes. We applied BAsE-Seq on mixed clones of hepatitis B virus and accurately identified haplotypes occurring at frequencies greater than or equal to 0.4%, with >99.9% specificity. Applying BAsE-Seq to a clinical sample, we obtained over 9,000 viral haplotypes, which provided an unprecedented view of hepatitis B virus population structure during chronic infection. BAsE-Seq is readily applicable for monitoring quasispecies evolution in viral diseases.


Assuntos
Haplótipos/genética , Vírus da Hepatite B/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Algoritmos , Variação Genética , Hepatite B/genética , Hepatite B/virologia , Humanos , Software
18.
J Neurosurg Spine ; 21(4): 529-37, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25105338

RESUMO

OBJECT: Anterior cervical plating decreases the risk of pseudarthrosis following anterior cervical discectomy and fusion (ACDF). Dysphagia is a common complication of ACDF, with the anterior plate implicated as a potential contributor. A zero-profile, stand-alone polyetheretherketone (PEEK) interbody spacer has been postulated to minimize soft-tissue irritation and postoperative dysphagia, but studies are limited. The object of the present study was to determine the clinical and radiological outcomes for patients who underwent ACDF using a zero-profile integrated plate and spacer device, with a focus on the course of postoperative prevertebral soft-tissue thickness and the incidence of dysphagia. METHODS: Using a surgical database, the authors conducted a retrospective analysis of all patients who had undergone ACDF between August 2008 and October 2011. All patients received a Zero-P implant (DePuy Synthes Spine). The Neck Disability Index (NDI) and visual analog scale (VAS) scores for arm and neck pain were documented. Dysphagia was determined using the Bazaz criteria. Prevertebral soft-tissue thickness, spinal alignment, and subsidence were assessed as well. RESULTS: Twenty-two male and 19 female consecutive patients, with a mean age of 58.4 ± 14.68, underwent ACDF (66 total operated levels) in the defined study period. The mean clinical follow-up in 36 patients was 18.6 ± 9.93 months. Radiological outcome in 37 patients was assessed at a mean follow-up of 9.76 months (range 7.2-19.7 months). There were significant improvements in neck and arm VAS scores and the NDI following surgery. The neck VAS score improved from a median of 6 (range 0-10) to 0 (range 0-8; p < 0.001). The arm VAS score improved from a median of 2 (range 0-10) to 0 (range 0-7; p = 0.006). Immediate postoperative dysphagia was experienced by 58.4% of all patients. Complete resolution was demonstrated in 87.8% of affected patients at the latest follow-up. The overall median Bazaz score decreased from 1 (range 0-3) immediately postoperatively to 0 (range 0-2; p < 0.001) at the latest follow-up. Prevertebral soft-tissue thickness significantly decreased across all levels from a mean of 15.8 ± 4.38 mm to 10.1 ± 2.93 mm. Postoperative lordosis was maintained at the latest follow-up. Mean subsidence from the immediate postoperative to the latest follow-up was 4.1 ± 4.7 mm (p < 0.001). Radiographic fusion was achieved in 92.6% of implants. No correlation was found between prevertebral soft-tissue thickness and Bazaz dysphagia score. CONCLUSIONS: A zero-profile integrated plate and spacer device for ACDF surgery produces clinical and radiological outcomes that are comparable to those for nonintegrated plate and spacer constructs. Chronic dysphagia rates are comparable to or better than those for previously published case series.


Assuntos
Placas Ósseas , Vértebras Cervicais/cirurgia , Discotomia/instrumentação , Próteses e Implantes , Fusão Vertebral/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Braço , Benzofenonas , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/prevenção & controle , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Cetonas , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cervicalgia/cirurgia , Medição da Dor , Polietilenoglicóis , Polímeros , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
19.
Opt Lett ; 39(7): 2137-40, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686694

RESUMO

We present an analytical solution for the phase introduced by a phase-only spatial light modulator to generate far-field phase and amplitude distributions within a domain of interest. The solution is demonstrated experimentally and shown to enable excellent control of the far-field amplitude and phase.

20.
World Neurosurg ; 82(1-2): e1-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23023049

RESUMO

BACKGROUND: The paucity of neurosurgical care in East Africa remains largely unaddressed. A sustained investment in local health infrastructures and staff training is needed to create an independent surgical capacity. The Madaktari organization has addressed this issue by starting initiatives to train local general surgeons and assistant medical officers in basic neurosurgical procedures. We report illustrative cases since beginning of the program in Mwanza in 2009 and focus on the most recent training period. METHODS: A multi-institutional neurosurgical training program and a surgical database was created at a tertiary referral center in Mwanza, Tanzania. We collected clinical data on consecutive patients who underwent a neurosurgical procedure between September 9th and December 1st, 2011. All procedures were performed by a local surgeon under the supervision of a visiting neurosurgeon. Since the inception of the training initiative, comprehensive multidisciplinary training courses in Tanzania and an annual visiting fellowship for East African surgeons to travel to a major U.S. medical center have been established. RESULTS: At initial visits infrastructure and feasibility of complex case scenarios was assessed. Surgeries for brain tumors and complex spinal cases were performed. During the 3-month training period, 62 patients underwent surgery. Pediatric hydrocephalus comprised 52% of patients, 11% suffered from meningomyelocelia, and 6% presented with an encephalocele. A total of 24% of patients were treated for trauma-related conditions, representing 75% of the adult patients. A total of 10% of patients had surgery because of traumatic spine injury, and 15% of operations were on patients with severe head injury. A total of 6% of patients presented with degenerative spine disease. One patient sustained a fatal perioperative complication. At the end of the training period, the local general surgeon was able to perform all basic neurosurgical cases independently. CONCLUSIONS: Neurosurgical care in Tanzania needs to address a diverse, unique disease burden. We found that local surgeons could be enabled to safely perform basic cranial and spinal neurosurgical procedures through immersive, 1-on-1 on-site collaborations, multidisciplinary courses, and educational visiting fellowships.


Assuntos
Neurocirurgia/educação , Centros de Atenção Terciária/organização & administração , Adulto , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/cirurgia , Transtornos da Consciência , Craniotomia , Crime , Cuidados Críticos , Europa (Continente) , Feminino , Escala de Coma de Glasgow , Humanos , Hidrocefalia/cirurgia , Unidades de Terapia Intensiva , Cooperação Internacional , Intercâmbio Educacional Internacional , Masculino , Pessoa de Meia-Idade , Tanzânia , Tuberculoma Intracraniano/cirurgia , Estados Unidos
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