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2.
Ann Biomed Eng ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796670

RESUMO

Biomimetic tumor microenvironment models bridge the gap between in vitro and in vivo systems and serve as a useful way to address the modeling challenge of how to recreate the cell and system complexity associated with real tissues. Our laboratory has developed an ex vivo rat mesentery culture model, which allows for simultaneous investigation of blood and lymphatic microvascular network remodeling in an intact tissue environment. Given that angiogenesis and lymphangiogenesis are key contributors to the progression of cancer, the objective of this study was to combine tissue and tumor spheroid culture methods to establish a novel ex vivo tumor spheroid-tissue model by verifying its use for evaluating the effects of cancer cell behavior on the local microvascular environment. H1299 or A549 tumor spheroids were formed via hanging drop culture and seeded onto rat mesenteric tissues harvested from adult male Wistar rats. Tissues with transplanted spheroids were cultured in serum-free media for 3 to 5 days. PECAM, NG2, CD11b, and αSMA labeling identified endothelial cells, pericytes, immune cells, and smooth muscle cells, respectively. Time-lapse imaging confirmed cancer cell type specific migration. In addition to increasing PECAM positive capillary sprouting and LYVE-1 positive endothelial cell extensions indicative of lymphangiogenesis, tumor spheroid presence induced the formation of lymphatic/blood vessel connections and the formation of hybrid, mosaic vessels that were characterized by discontinuous LYVE-1 labeling. The results support the application of a novel tumor spheroid microenvironment model for investigating cancer cell-microvascular interactions.

3.
bioRxiv ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38562905

RESUMO

Epidemiological studies have shown that circadian rhythm disruption (CRD) is associated with the risk of breast cancer. However, the role of CRD in mammary gland morphology and aggressive basal mammary tumorigenesis and the molecular mechanisms underlying CRD and cancer risk remain unknown. To investigate the effect of CRD on aggressive tumorigenesis, a genetically engineered mouse model that recapitulates the human basal type of breast cancer was used for this study. The effect of CRD on mammary gland morphology was investigated using wild-type mice model. The impact of CRD on the tumor microenvironment was investigated using the tumors from LD12:12 and CRD mice via scRNA seq. ScRNA seq was substantiated by multiplexing immunostaining, flow cytometry, and realtime PCR. The effect of LILRB4 immunotherapy on CRD-induced tumorigenesis was also investigated. Here we identified the impact of CRD on basal tumorigenesis and mammary gland morphology and identified the role of LILRB4 on CRD-induced lung metastasis. We found that chronic CRD disrupted mouse mammary gland morphology and increased tumor burden, and lung metastasis and induced an immunosuppressive tumor microenvironment by enhancing LILRB4a expression. Moreover, CRD increased the M2-macrophage and regulatory T-cell populations but decreased the M1-macrophage populations. Furthermore, targeted immunotherapy against LILRB4 reduced CRD-induced immunosuppressive microenvironment and lung metastasis. These findings identify and implicate LILRB4a as a link between CRD and aggressive mammary tumorigenesis. This study also establishes the potential role of the targeted LILRB4a immunotherapy as an inhibitor of CRD-induced lung metastasis.

4.
J Gastrointest Oncol ; 14(2): 874-885, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37201079

RESUMO

Background: To evaluate overall survival (OS), progression-free survival (PFS) and toxicity after resin Yttrium-90 (Y-90) radioembolization in Barcelona Clinic Liver Cancer B (BCLC B) hepatocellular carcinoma (HCC) patients using the Bolondi subgroup classification. Methods: A total of 144 BCLC B patients were treated between 2015-2020. Patients were broken into 4 subgroups by tumor burden/liver function tests with 54, 59, 8 and 23 in subgroups 1, 2, 3 and 4. OS and PFS were calculated with Kaplan-Meier analysis with 95% confidence intervals. Toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE) v5. Results: Prior resection and chemoembolization were performed in 19 (13%) and 34 (24%) of patients. There were no deaths within 30 days. Median OS and PFS for the cohort were 21.5 and 12.4 months. Median OS was not reached for subgroup 1 at a mean 28.8 months, and was 24.9, 11.0 and 14.6 months for subgroups 2-4 (χ2=19.8, P=0.0002). PFS by BCLC B subgroup was 13.8, 12.4, 4.5, and 6.6 months (χ2=16.8, P=0.0008). The most common Grade 3 or 4 toxicities were elevated bilirubin (n=16, 13.3%) and decreased albumin (n=15, 12.5%). Grade 3 or greater bilirubin (32% vs. 10%, P=0.03) and albumin (26% vs. 10%, P=0.03) toxicity were more common in the subgroup 4 patients. Conclusions: The Bolondi subgroup classification stratifies OS, PFS and development of toxicity in patients treated with resin Y-90 microspheres. OS in subgroup 1 approaches 2.5 years and Grade 3 or greater hepatic toxicity profile in subgroups 1-3 is low.

5.
Front Bioeng Biotechnol ; 10: 912073, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795159

RESUMO

The gap between in vitro and in vivo assays has inspired biomimetic model development. Tissue engineered models that attempt to mimic the complexity of microvascular networks have emerged as tools for investigating cell-cell and cell-environment interactions that may be not easily viewed in vivo. A key challenge in model development, however, is determining how to recreate the multi-cell/system functional complexity of a real network environment that integrates endothelial cells, smooth muscle cells, vascular pericytes, lymphatics, nerves, fluid flow, extracellular matrix, and inflammatory cells. The objective of this mini-review is to overview the recent evolution of popular biomimetic modeling approaches for investigating microvascular dynamics. A specific focus will highlight the engineering design requirements needed to match physiological function and the potential for top-down tissue culture methods that maintain complexity. Overall, examples of physiological validation, basic science discoveries, and therapeutic evaluation studies will emphasize the value of tissue culture models and biomimetic model development approaches that fill the gap between in vitro and in vivo assays and guide how vascular biologists and physiologists might think about the microcirculation.

6.
J Pediatr ; 249: 43-49, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35779742

RESUMO

OBJECTIVES: To assess the relationship between an Area Deprivation Index (ADI) and a Social Determinant of Health (SDoH) measure within a diverse sample. A prescreening tool based on routinely collected information could reduce clinical burden by identifying patients impacted by SDoH for comprehensive assessment. STUDY DESIGN: In total, 499 consented pediatric patient-families who spoke English, Spanish, or Arabic and had a child ≤12 years receiving primary care at a large academic institution were enrolled. Participants completed the Health Leads Social Needs (HLSN) survey. Residential address was extracted from the electronic health record to calculate Brokamp ADI at the census-tract level. The main outcome was the correlations between the total HLSN score and Brokamp ADI, overall and in each language subgroup. ADI distributions were also compared between participants with/without need for each of the 8 HLSN survey SDoH domains, using 2-sample t-tests and Pearson χ2 tests. RESULTS: In total, 54.9% of participants were English-speaking, 30.9% were Spanish-speaking, and 14.2% were Arabic-speaking. Spearman correlations between Brokamp ADI and total HLSN score were overall (rs = 0.15; P = .001), English (rs = 0.12; P = .04), Spanish (rs = 0.03; P = .7), and Arabic (rs = 0.24; P = .04). SDoH domain analyses found significant ADI differences between those with/without need in housing instability, childcare, transportation, and health literacy. CONCLUSIONS: There were small but statistically significant associations between the Brokamp ADI and total HLSN score and SDoH domains of housing instability, childcare, transportation, and health literacy. These findings support testing the Brokamp ADI as a prescreening tool to help identify patients with social needs in an outpatient clinical setting.


Assuntos
Atenção Primária à Saúde , Privação Social , Determinantes Sociais da Saúde , Criança , Humanos , Inquéritos Epidemiológicos , Medição de Risco
8.
Radiol Case Rep ; 16(9): 2376-2381, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34306285

RESUMO

The high technical success rate of transjugular intrahepatic portosystemic shunt (TIPS) placement makes the procedure a popular treatment option for symptomatic portal hypertension. Among the major drawbacks of the procedure - hepatic encephalopathy, acute hepatic failure, hemorrhage, biliary injury - TIPS dysfunction is one of the most prevalent, often requiring endovascular reintervention. Conventional techniques for shunt revision rely on transjugular access to the stent; but in technically difficult cases of abnormal angulation or severe stenosis, transhepatic access may also be required. The pull-through method utilizes both transjugular and transhepatic access to achieve stable through-and-through access in order to advance a sheath into the stent and recannulate the shunt. In the case of TIPS foreshortening, however, the distal end of the stent may abut the wall of the hepatic vein, jailing it off and obviating the advancement of a wire out of that end. We present here a case of a modified pull-through method for TIPS revision whereby a transhepatic wire is passed through the interstices of the stent at the distal end to enter into the hepatic vein and IVC. Subsequent snaring of the wire at the transjugular end establishes through-and-through access, and balloon dilation through the interstices allows for insertion of a transjugular sheath into the TIPS stent for recanalization. Our case highlights how the modified pull-through method, using trans-stent access, can be safely performed in patients with a foreshortened TIPS that abuts against the hepatic and portal vessel walls.

9.
JSES Int ; 5(3): 549-553, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34136869

RESUMO

BACKGROUND: The ulnar collateral ligament (UCL) complex of the elbow plays a primary role in valgus and posteromedial stability of the elbow. The anterior oblique ligament (AOL) of the UCL is believed to provide the majority of resistance to external forces on the medial elbow. The transverse ligament (TL) of the UCL is generally thought to have minimal contribution to the elbow's overall stability. However, recent studies have suggested a more significant role for the TL. The primary aim of this study was to identify the TL's contribution to the stability of the elbow joint in determining the joint stiffness and neutral zone variation in internal rotation. METHODS: Twelve cadaveric elbows, set at a 90° flexion angle, were tested by applying an internal rotational force on the humerus to generate a medial opening torque at the level of the elbow. The specimens were preconditioned with 10 cycles of humeral internal rotation with sinusoidal torque ranging from 0 to 5 Nm. Elbow stiffness measures and joint neutral zone were first evaluated in its integrity during a final ramp loading. The test was subsequently repeated after cutting the TL at 33%, 66%, and 100% followed by the AOL in the same fashion. RESULTS: The native UCL complex joint stiffness to internal rotation measured 1.52 ± 0.51 Nm/°. The first observable change occurred with 33% sectioning of the AOL, with further sectioning of the AOL minimizing the joint stiffness to 1.26 ± 0.32 Nm/° (P = .004). A 33% resection of the TL found an initial neutral zone variation of 0.376 ± 0.23° that increased to 0.771 ± 0.41° (P < .01) at full resection. These values were marginal when compared with the full resection of the AOL for which we have found 3.69 ± 1.65° (P < .01). CONCLUSION: The TL had no contribution to internal rotation elbow joint stiffness at a flexion angle of 90°. However, sequential sectioning of the TL was found to significantly increase the joint neutral zone when compared with the native cadaveric elbow at a flexion angle of 90°. This provides evidence toward the TL having some form of contribution to the elbow's overall stability.

10.
Radiol Case Rep ; 16(6): 1586-1590, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33995749

RESUMO

Gastrostomy tube placement is an appropriate option for long-term nutritional support for patients who cannot tolerate oral intake. Common indications for a gastrostomy tube include head and neck tumors and neurological disorders. Several methods for gastrostomy tube insertion exist (eg, surgical, endoscopic, and radiologic) that require sedation or general anesthesia, which can pose risks of cardiopulmonary compromise and postsurgical pulmonary complications. Unlike other methods, our practice uses a percutaneous balloon-assisted gastrostomy tube insertion method for which we can perform without sedation. We report a case of a percutaneous radiologic gastrostomy procedure for a patient with end stage lung disease as a bridge to lung transplantation, who is not a candidate for sedation and is high-risk for general anesthesia. Through enteral feeds administered through the successfully placed gastrostomy tube, the patient showed steady improvement in weight gain over the course of several months before approval for listing by the lung transplant selection committee. Our case highlights how gastrostomy tube placement can be safely performed in patients who are not sedation candidates using the minimally invasive balloon-assisted gastrostomy tube insertion method and local anesthetic.

11.
Acad Radiol ; 28(7): 922-929, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33896717

RESUMO

INTRODUCTION: Black radiologists remain significantly underrepresented in the radiology workforce, despite a 1973 plea by Black radiologists of the National Medical Association to increase training programs for minority radiologists. OBJECTIVE: The authors provide a qualitative narrative that highlights the radiology residency programs of three historically Black schools of medicine (HBSOM) in the U.S., their contributions, and lessons learned from their closure. METHODS: Data from public repositories, interviews, and conversations were conflated to chronicle significant events and establish a timeline during these residency programs' existence. RESULTS: Radiology residencies at Howard University School of Medicine (1945), Meharry Medical College (1949), and Charles R. Drew University of Medicine and Science (1972) were established to train Black doctors to treat communities of color. These programs provided care to underserved and under-resourced areas of the country, where inequitable health care fueled a legacy of poor health outcomes. These radiology residency programs collapsed under the weight of suboptimal funding, strapped capital budgets, attrition of faculty, a declining hospital patient census, and failure to maintain other residency specialty programs.` CONCLUSION: Understanding the history and impact of these programs, and of their closure, can be leveraged to develop strategies to increase the representation of racial and ethnic minorities in radiology. Possible reinstatement, with appropriate allocation of resources and creation of intentional policies to ensure sustained success, merits further investigation and may be a pathway to achieve optimal representation.


Assuntos
Internato e Residência , Radiologia , Negro ou Afro-Americano , Humanos , Grupos Minoritários , Instituições Acadêmicas , Faculdades de Medicina , Estados Unidos
12.
Sci Rep ; 10(1): 4337, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152395

RESUMO

The two vasoactive hormones, angiotensin II (ANG II; vasoconstrictive) and atrial natriuretic peptide (ANP; vasodilatory) antagonize the biological actions of each other. ANP acting through natriuretic peptide receptor-A (NPRA) lowers blood pressure and blood volume. We tested hypothesis that ANG II plays critical roles in the transcriptional repression of Npr1 (encoding NPRA) and receptor function. ANG II significantly decreased NPRA mRNA and protein levels and cGMP accumulation in cultured mesangial cells and attenuated ANP-mediated relaxation of aortic rings ex vivo. The transcription factors, cAMP-response element-binding protein (CREB) and heat-shock factor-4a (HSF-4a) facilitated the ANG II-mediated repressive effects on Npr1 transcription. Tyrosine kinase (TK) inhibitor, genistein and phosphatidylinositol 3-kinase (PI-3K) inhibitor, wortmannin reversed the ANG II-dependent repression of Npr1 transcription and receptor function. ANG II enhanced the activities of Class I histone deacetylases (HDACs 1/2), thereby decreased histone acetylation of H3K9/14ac and H4K8ac. The repressive effect of ANG II on Npr1 transcription and receptor signaling seems to be transduced by TK and PI-3K pathways and modulated by CREB, HSF-4a, HDACs, and modified histones. The current findings suggest that ANG II-mediated repressive mechanisms of Npr1 transcription and receptor function may provide new molecular targets for treatment and prevention of hypertension and cardiovascular diseases.


Assuntos
Angiotensina II/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Fatores de Transcrição de Choque Térmico/metabolismo , Histona Desacetilases/metabolismo , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo , Acetilação , Angiotensina II/farmacologia , Animais , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição de Choque Térmico/genética , Histonas/metabolismo , Camundongos , Modelos Biológicos , Ligação Proteica , Ativação Transcricional/efeitos dos fármacos
13.
Nat Commun ; 8: 15376, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28548097

RESUMO

The controlled creation of defect centre-nanocavity systems is one of the outstanding challenges for efficiently interfacing spin quantum memories with photons for photon-based entanglement operations in a quantum network. Here we demonstrate direct, maskless creation of atom-like single silicon vacancy (SiV) centres in diamond nanostructures via focused ion beam implantation with ∼32 nm lateral precision and <50 nm positioning accuracy relative to a nanocavity. We determine the Si+ ion to SiV centre conversion yield to be ∼2.5% and observe a 10-fold conversion yield increase by additional electron irradiation. Low-temperature spectroscopy reveals inhomogeneously broadened ensemble emission linewidths of ∼51 GHz and close to lifetime-limited single-emitter transition linewidths down to 126±13 MHz corresponding to ∼1.4 times the natural linewidth. This method for the targeted generation of nearly transform-limited quantum emitters should facilitate the development of scalable solid-state quantum information processors.

14.
PLoS Genet ; 12(8): e1006271, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27529578

RESUMO

[This corrects the article DOI: 10.1371/journal.pgen.1006135.].

15.
PLoS Genet ; 12(7): e1006135, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27414651

RESUMO

Dietary restriction (DR) is a dietary regimen that extends lifespan in many organisms. One mechanism contributing to the conserved effect of DR on longevity is the cellular recycling process autophagy, which is induced in response to nutrient scarcity and increases sequestration of cytosolic material into double-membrane autophagosomes for degradation in the lysosome. Although autophagy plays a direct role in DR-mediated lifespan extension in the nematode Caenorhabditis elegans, the contribution of autophagy in individual tissues remains unclear. In this study, we show a critical role for autophagy in the intestine, a major metabolic tissue, to ensure lifespan extension of dietary-restricted eat-2 mutants. The intestine of eat-2 mutants has an enlarged lysosomal compartment and flux assays indicate increased turnover of autophagosomes, consistent with an induction of autophagy in this tissue. This increase in intestinal autophagy may underlie the improved intestinal integrity we observe in eat-2 mutants, since whole-body and intestinal-specific inhibition of autophagy in eat-2 mutants greatly impairs the intestinal barrier function. Interestingly, intestinal-specific inhibition of autophagy in eat-2 mutants leads to a decrease in motility with age, alluding to a potential cell non-autonomous role for autophagy in the intestine. Collectively, these results highlight important functions for autophagy in the intestine of dietary-restricted C. elegans.


Assuntos
Autofagia/fisiologia , Caenorhabditis elegans/fisiologia , Restrição Calórica , Intestinos/fisiologia , Longevidade , Animais , Animais Geneticamente Modificados , Citosol/metabolismo , Feminino , Genes Reporter , Proteínas de Fluorescência Verde/metabolismo , Insulina/metabolismo , Lisossomos/metabolismo , Masculino , Movimento , Mutação , Neurônios/metabolismo , Fenótipo , Regiões Promotoras Genéticas , Interferência de RNA , Temperatura , Proteínas rab3 de Ligação ao GTP/genética
16.
J Oral Implantol ; 42(2): 145-52, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26103153

RESUMO

The specific aim of this study was to examine the relative contributions to the implant insertion torque value (ITV) by cortical and trabecular components of an in vitro bone model. Simulated bone blocks of polyurethane were used with 2 densities of foam (0.08 g/cm(3) to mimic trabecular bone and 0.64 g/cm(3) to mimic cortical bone). We have developed a new platform technology to collect data that enables quantitative evaluation of ITV at different implant locations. Seven groups were used to model varying thicknesses of cortical bone over a lower-quality trabecular bone that have clinical significance: a solid 0.08 g/cm(3) block; 1 mm, 2 mm, and 3 mm thick 0.64 g/cm(3) sheets with no underlayer; and 1 mm, 2 mm, and 3 mm thick 0.64 g/cm(3) sheets laminated on top of a 4 cm thick 0.08 g/cm(3) block. The ITVs were recorded as a function of insertion displacement distance. Relative contributions of ITV ranged from 3% to 18% from trabecular bone, and 62% to 74% from cortical bone depending on the thickness of the cortical layer. Inserting an implant into 2-mm and 3-mm cortical layers laminated atop trabecular blocks had a synergistic effect on ITVs. Finally, an implant with a reverse bevel design near the abutment showed final average torque values that were 14% to 34% less than their maximum torque values. This work provides basic quantitative information for clinicians to understand the influence of composite layers of bone in relation to mechanical torque resistances during implant insertion in order to obtain desired primary implant stability.


Assuntos
Osso Cortical , Implantes Dentários , Densidade Óssea , Osso e Ossos , Torque
17.
Cancer Genet Cytogenet ; 160(2): 120-5, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15993267

RESUMO

We performed cytogenetic analyses of 8 renal oncocytomas to identify chromosomal regions involved in the tumorigenesis of oncocytomas. All cases showed chromosomal findings corresponding to established cytogenetic subsets of renal oncocytomas: 3 cases with normal karyotypes, 1 case with rearrangement of 11q, and 4 cases with losses of chromosome 14. In the latter cytogenetic subgroup, monosomy 14 was additionally accompanied by either monosomy 1 in 2 cases or loss of 1p in a third case, providing insights in the cytogenetic evolution of this subgroup.


Assuntos
Adenoma Oxífilo/genética , Aneuploidia , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 1/genética , Neoplasias Renais/genética , Adenoma Oxífilo/patologia , Adulto , Idoso , Feminino , Humanos , Cariotipagem , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade
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