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1.
Opt Express ; 32(4): 6241-6257, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439332

RESUMO

Imaging through scattering is a pervasive and difficult problem in many biological applications. The high background and the exponentially attenuated target signals due to scattering fundamentally limits the imaging depth of fluorescence microscopy. Light-field systems are favorable for high-speed volumetric imaging, but the 2D-to-3D reconstruction is fundamentally ill-posed, and scattering exacerbates the condition of the inverse problem. Here, we develop a scattering simulator that models low-contrast target signals buried in heterogeneous strong background. We then train a deep neural network solely on synthetic data to descatter and reconstruct a 3D volume from a single-shot light-field measurement with low signal-to-background ratio (SBR). We apply this network to our previously developed computational miniature mesoscope and demonstrate the robustness of our deep learning algorithm on scattering phantoms with different scattering conditions. The network can robustly reconstruct emitters in 3D with a 2D measurement of SBR as low as 1.05 and as deep as a scattering length. We analyze fundamental tradeoffs based on network design factors and out-of-distribution data that affect the deep learning model's generalizability to real experimental data. Broadly, we believe that our simulator-based deep learning approach can be applied to a wide range of imaging through scattering techniques where experimental paired training data is lacking.

2.
Opt Express ; 31(7): 11007-11018, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155746

RESUMO

Topography measurement is essential for surface characterization, semiconductor metrology, and inspection applications. To date, performing high-throughput and accurate topography remains challenging due to the trade-off between field-of-view (FOV) and spatial resolution. Here we demonstrate a novel topography technique based on the reflection-mode Fourier ptychographic microscopy, termed Fourier ptychograhpic topography (FPT). We show that FPT provides both a wide FOV and high resolution, and achieves nanoscale height reconstruction accuracy. Our FPT prototype is based on a custom-built computational microscope consisting of programmable brightfield and darkfield LED arrays. The topography reconstruction is performed by a sequential Gauss-Newton-based Fourier ptychographic phase retrieval algorithm augmented with total variation regularization. We achieve a synthetic numerical aperture (NA) of 0.84 and a diffraction-limited resolution of 750 nm, increasing the native objective NA (0.28) by 3×, across a 1.2 × 1.2 mm2 FOV. We experimentally demonstrate the FPT on a variety of reflective samples with different patterned structures. The reconstructed resolution is validated on both amplitude and phase resolution test features. The accuracy of the reconstructed surface profile is benchmarked against high-resolution optical profilometry measurements. In addition, we show that the FPT provides robust surface profile reconstructions even on complex patterns with fine features that cannot be reliably measured by the standard optical profilometer. The spatial and temporal noise of our FPT system is characterized to be 0.529 nm and 0.027 nm, respectively.

3.
Blood ; 131(26): 2943-2954, 2018 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-29695515

RESUMO

Prostate apoptosis response-4 (Par-4), a proapoptotic tumor suppressor protein, is downregulated in many cancers including renal cell carcinoma, glioblastoma, endometrial, and breast cancer. Par-4 induces apoptosis selectively in various types of cancer cells but not normal cells. We found that chronic lymphocytic leukemia (CLL) cells from human patients and from Eµ-Tcl1 mice constitutively express Par-4 in greater amounts than normal B-1 or B-2 cells. Interestingly, knockdown of Par-4 in human CLL-derived Mec-1 cells results in a robust increase in p21/WAF1 expression and decreased growth due to delayed G1-to-S cell-cycle transition. Lack of Par-4 also increased the expression of p21 and delayed CLL growth in Eµ-Tcl1 mice. Par-4 expression in CLL cells required constitutively active B-cell receptor (BCR) signaling, as inhibition of BCR signaling with US Food and Drug Administration (FDA)-approved drugs caused a decrease in Par-4 messenger RNA and protein, and an increase in apoptosis. In particular, activities of Lyn, a Src family kinase, spleen tyrosine kinase, and Bruton tyrosine kinase are required for Par-4 expression in CLL cells, suggesting a novel regulation of Par-4 through BCR signaling. Together, these results suggest that Par-4 may play a novel progrowth rather than proapoptotic role in CLL and could be targeted to enhance the therapeutic effects of BCR-signaling inhibitors.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Regulação Leucêmica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Ciclo Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Deleção de Genes , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Regulação para Cima
4.
Allergy ; 75(4): 911-920, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31713250

RESUMO

BACKGROUND: Chronic rhinosinusitis (CRS) epidemiology has been largely studied using symptom-based case definitions, without assessment of objective sinus findings. OBJECTIVE: To describe radiologic sinus opacification and the prevalence of CRS, defined by the co-occurrence of symptoms and sinus opacification, in a general population-based sample. METHODS: We collected questionnaires and sinus CT scans from 646 participants selected from a source population of 200 769 primary care patients. Symptom status (CRSS ) was based on guideline criteria, and objective radiologic inflammation (CRSO ) was based on the Lund-Mackay (L-M) score using multiple L-M thresholds for positivity. Participants with symptoms and radiologic inflammation were classified as CRSS+O . We performed negative binomial regression to assess factors associated with L-M score and logistic regression to evaluate factors associated with CRSS+O . Using weighted analysis, we calculated estimates for the source population. RESULTS: The proportion of women with L-M scores ≥ 3, 4, or 6 (CRSO ) was 11.1%, 9.9%, and 5.7%, respectively, and 16.1%, 14.6%, and 8.7% among men. The respective proportion with CRSS+O was 1.7%, 1.6%, and 0.45% among women and 8.8%, 7.5%, and 3.6% among men. Men had higher odds of CRSS+O compared to women. A greater proportion of men (vs women) had any opacification in the frontal, anterior ethmoid, and sphenoid sinuses. CONCLUSION: In a general population-based sample in Pennsylvania, sinus opacification was more common among men than in women and opacification occurred in different locations by sex. Male sex, migraine headache, and prior sinus surgery were associated with higher odds of CRSS+O .


Assuntos
Seios Paranasais , Rinite , Sinusite , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Seios Paranasais/diagnóstico por imagem , Pennsylvania , Rinite/diagnóstico por imagem , Rinite/epidemiologia , Sinusite/diagnóstico por imagem , Sinusite/epidemiologia , Adulto Jovem
5.
Knee Surg Sports Traumatol Arthrosc ; 28(2): 509-518, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31538227

RESUMO

PURPOSE: Quadriceps tendon (QT) autograft ACL reconstruction was hypothesized to possess less anterior knee laxity, pivot shift laxity, and lower failure rates than hamstring tendon (HT) autografts. METHODS: Terms "hamstring tendon autograft" and "ACL reconstruction" or "quadriceps tendon autograft" and "ACL reconstruction" were searched in Embase and PubMed. Inclusion criteria required that studies included patients treated for primary ACL injury with reconstruction using either a QT autograft (Group 1) or a HT autograft (Group 2) and instrumented anterior knee laxity assessment. Extracted information included surgical fixation method, graft type, graft thickness or diameter, single vs. double bundle surgical method, publication year, time between the index knee injury and surgery, % women, initial and final subject number, subject age, follow-up length, side-to-side anterior knee laxity difference, Lysholm Score, Subjective IKDC score, anterior knee laxity side-to-side difference grade, ipsilateral pivot shift laxity grade, and failure rate. The Methodological Index for Nonrandomized Studies was used to evaluate study methodological quality. RESULTS: The QT group (Group 1) had 17 studies and the HT group (Group 2) had 61 studies. Overall, Group 2 had greater pivot shift laxity (OR 1.29, 95% CI 1.05-1.59, p = 0.005). Group 2 suspensory femoral fixation had greater pivot shift laxity (OR 1.26, 95% CI 1.01-1.58, p = 0.02) than Group 1 compression femoral fixation. Group 2 compression femoral fixation also had more anterior knee laxity (OR 1.25, 95% CI 1.03-1.52, p = 0.01) than Group 1 compression femoral fixation and higher failure rates based on initial (OR 1.69, 95% CI 1.18-2.4, p = 0.002) and final (OR 1.89, 95% CI 1.32-2.71, p = 0.0003) subject number. Failure rate for HT compression femoral fixation was greater than suspensory femoral fixation based on initial (OR 2.08, 95% CI 1.52-2.84, p < 0.0001) and final (OR 2.26, 95% CI 1.63-3.16, p < 0.0001) subject number. CONCLUSIONS: Overall, QT autografts had less pivot shift laxity and lower failure rates based on final subject number than HT autografts. Compression QT autograft femoral fixation had lower pivot shift laxity than suspensory HT autograft femoral fixation. Compression QT autograft femoral fixation had less anterior knee laxity and lower failure rates than compression HT autograft femoral fixation. Suspensory HT autograft femoral fixation had lower failure rates than compression HT autograft femoral fixation. Greater knee laxity and failure rates may be related to a combination of HT autograft diameter and configuration (tissue quality and dimensions, strands, bundles, and suturing method) variability and fixation mode. LEVEL OF EVIDENCE: Level IV.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Tendões dos Músculos Isquiotibiais/transplante , Instabilidade Articular/diagnóstico , Músculo Quadríceps/transplante , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Autoenxertos , Sobrevivência de Enxerto , Humanos , Instabilidade Articular/etiologia , Articulação do Joelho/cirurgia , Exame Físico , Tendões/transplante , Transplante Autólogo , Falha de Tratamento
6.
Arthroscopy ; 34(7): 2201-2206, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29656809

RESUMO

PURPOSE: This study attempted to define a reproducible "safe zone" based on extra- and intra-articular knee anatomy for placing one or 2 accessory portals in the lateral tibiofemoral compartment for posterolateral region viewing. METHODS: Standard portals were created in 10 cadaveric knees to enable posterolateral region arthroscopic lateral tibiofemoral joint compartment viewing. After identifying the lateral knee surface tissue "soft spot," an accessory posterolateral portal (A) was created using an 18-gauge spinal needle and 4-mm cannula under direct visualization of a 70° arthroscope through the anteromedial portal. A second accessory portal (B) was then created 1 cm posterior and 1 cm superior to portal A. Accessory portal locations were measured relative to capsular fold and popliteus tendon locations. Distances from the peroneal nerve, lateral collateral ligament, popliteus tendon, and the biceps tendon were determined. Statistical analysis compared portal location differences from key anatomical structures (P < .05). RESULTS: Accessory portal A (mean ± 95% confidence interval) was located 8.8 ± 2.7 mm from the popliteus tendon, 11.6 ± 2.7 mm from the lateral collateral ligament (LCL), 26.8 ± 2.3 mm from the peroneal nerve, and 4.9 ± 2.5 mm from the biceps tendon. Accessory portal B was located 17.3 ± 2.8 mm from the popliteus tendon, 20 ± 2.8 mm from the LCL, 30.3 ± 3.3 mm from the peroneal nerve, and 7.0 ± 4.8 mm from the biceps tendon. Accessory portal B was located a greater distance from the LCL and the popliteus tendon than portal A (P < .0001). CONCLUSIONS: Using intra- and extra-articular anatomic landmarks, both accessory portals could be safely placed in the lateral tibiofemoral joint compartment to enable posterolateral region viewing. Accessory portals used individually or in combination may enable easier posterolateral region viewing for arthroscopic repair of lateral tibiofemoral compartment structures. CLINICAL RELEVANCE: Lateral tibiofemoral compartment portals can be safely created to enable improved visibility for complex arthroscopic procedures in the posterolateral viewing region.


Assuntos
Artroscopia/métodos , Articulação do Joelho/cirurgia , Ligamentos Articulares/cirurgia , Artroscópios , Artroscopia/instrumentação , Cadáver , Feminino , Humanos , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/inervação , Ligamentos Articulares/anatomia & histologia , Ligamentos Articulares/inervação , Masculino , Pessoa de Meia-Idade , Nervo Fibular/anatomia & histologia
7.
J Med Pract Manage ; 29(4): 250-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24696967

RESUMO

The provision of care and business of musculoskeletal medicine have evolved signifncalty over the last two decades. It has become ever more important that those who are leading muskuloskeletal medicine practices evolve with the changing healthcare landscape and find new ways to provide higher quliaty and more cost-effetive care. To meet these new challenges, many orthopedic physicians are choosing to hire athletic trainers as a part of their office staff. Athletic trainers provide value to a medical practice through their skills in triage, taking patient histories, performing musculoskeletal evaluations, providing instruction on exercise prescription, rehabilitation, and general patient education. If a practice can become more efficient by narroworring staff to a single ancillary provider that encompasses several skills at a high level, this is where patient throughput and patient satisfaction scores can be improved by the athletic trainer as a physician extender.


Assuntos
Pessoal Técnico de Saúde/economia , Eficiência Organizacional/economia , Ortopedia , Administração da Prática Médica/economia , Papel Profissional , Humanos , Satisfação do Paciente
8.
Biomed Opt Express ; 15(7): 4101-4110, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39022539

RESUMO

HiLo microscopy is an optical sectioning structured illumination microscopy technique based on computationally combining two images: one with uniform illumination and the other with structured illumination. The most widely used structured illumination in HiLo microscopy is random speckle patterns, due to their simplicity and resilience to tissue scattering. Here, we present a novel HiLo microscopy strategy based on random caustic patterns. Building on an off-the-shelf diffuser and a low-coherence LED source, we demonstrate that caustic HiLo can achieve 4.5 µm optical sectioning capability with a 20× 0.75 NA objective. In addition, with the distinct intensity statistical properties of caustic patterns, we show that our caustic HiLo outperforms speckle HiLo, achieving enhanced optical sectioning capability and preservation of fine features by imaging scattering fixed brain sections of 100 µm, 300 µm, and 500 µm thicknesses. We anticipate that this new structured illumination technique may find various biomedical imaging applications.

9.
Light Sci Appl ; 13(1): 144, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918363

RESUMO

Ultrafast 3D imaging is indispensable for visualizing complex and dynamic biological processes. Conventional scanning-based techniques necessitate an inherent trade-off between acquisition speed and space-bandwidth product (SBP). Emerging single-shot 3D wide-field techniques offer a promising alternative but are bottlenecked by the synchronous readout constraints of conventional CMOS systems, thus restricting data throughput to maintain high SBP at limited frame rates. To address this, we introduce EventLFM, a straightforward and cost-effective system that overcomes these challenges by integrating an event camera with Fourier light field microscopy (LFM), a state-of-the-art single-shot 3D wide-field imaging technique. The event camera operates on a novel asynchronous readout architecture, thereby bypassing the frame rate limitations inherent to conventional CMOS systems. We further develop a simple and robust event-driven LFM reconstruction algorithm that can reliably reconstruct 3D dynamics from the unique spatiotemporal measurements captured by EventLFM. Experimental results demonstrate that EventLFM can robustly reconstruct fast-moving and rapidly blinking 3D fluorescent samples at kHz frame rates. Furthermore, we highlight EventLFM's capability for imaging of blinking neuronal signals in scattering mouse brain tissues and 3D tracking of GFP-labeled neurons in freely moving C. elegans. We believe that the combined ultrafast speed and large 3D SBP offered by EventLFM may open up new possibilities across many biomedical applications.

10.
Elife ; 132024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742856

RESUMO

The type II class of RAF inhibitors currently in clinical trials paradoxically activate BRAF at subsaturating concentrations. Activation is mediated by induction of BRAF dimers, but why activation rather than inhibition occurs remains unclear. Using biophysical methods tracking BRAF dimerization and conformation, we built an allosteric model of inhibitor-induced dimerization that resolves the allosteric contributions of inhibitor binding to the two active sites of the dimer, revealing key differences between type I and type II RAF inhibitors. For type II inhibitors the allosteric coupling between inhibitor binding and BRAF dimerization is distributed asymmetrically across the two dimer binding sites, with binding to the first site dominating the allostery. This asymmetry results in efficient and selective induction of dimers with one inhibited and one catalytically active subunit. Our allosteric models quantitatively account for paradoxical activation data measured for 11 RAF inhibitors. Unlike type II inhibitors, type I inhibitors lack allosteric asymmetry and do not activate BRAF homodimers. Finally, NMR data reveal that BRAF homodimers are dynamically asymmetric with only one of the subunits locked in the active αC-in state. This provides a structural mechanism for how binding of only a single αC-in inhibitor molecule can induce potent BRAF dimerization and activation.


Assuntos
Inibidores de Proteínas Quinases , Multimerização Proteica , Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/química , Regulação Alostérica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/metabolismo , Multimerização Proteica/efeitos dos fármacos , Humanos , Conformação Proteica , Ligação Proteica , Modelos Moleculares
11.
J Arthroplasty ; 28(4): 570-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23183277

RESUMO

While the number of revision total knee arthoplasties (TKA) performed in the United States continues to rise annually, controversy exists whether intramedullary stems should be cemented or press-fit. Retrospective analysis of midterm survivorship rate of revision TKA using hybrid stem fixation in 119 patients was performed. Revision was performed predominantly for aseptic loosening (78) and infections (28). Average follow-up was 62months (range, 46-80). Knee Society Pain and Function scores improved from 39 and 58 to 68 and 79 (P<.05). Fifty-eight tibial offsets and 28 femoral offsets were utilized. Three knees (2.5%) required revision without any cases of aseptic loosening. Radiographic complete or progressively advanced (>2mm) radiolucent lines were not observed in any patient. At mid-term follow-up, revision hybrid TKA provides excellent fixation with extremely low rates of aseptic loosening and avoids the inherent complications of extensive intramedullary cement.


Assuntos
Artroplastia do Joelho/métodos , Cimentos Ósseos , Prótese do Joelho , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
12.
J Knee Surg ; 26(1): 69-74, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23288764

RESUMO

Using single femoral and tibial tunnels, we describe a technique of anatomically recreating the anteromedial and posterolateral anterior cruciate ligament (ACL) bundles. Transtibial, flexible reamers are utilized to create a "Figure 8" notched tunnel thereby recreating the anatomic footprint of the femoral insertion of the ACL. Rotational control of the individual bundles is created via the notched tunnel and each bundle is tensioned to 80 N individually. Anatomic double bundle ACL reconstruction is created in a reproducible modified single-bundle technique without the inherent risks associated with drilling four tunnels.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/métodos , Ligamento Cruzado Anterior/cirurgia , Técnicas de Sutura , Tendões/transplante , Artroscopia/métodos , Fêmur/cirurgia , Humanos , Tíbia/cirurgia , Transplante Homólogo
13.
Neurophotonics ; 10(4): 044302, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37215637

RESUMO

Significance: Fluorescence head-mounted microscopes, i.e., miniscopes, have emerged as powerful tools to analyze in-vivo neural populations but exhibit a limited depth-of-field (DoF) due to the use of high numerical aperture (NA) gradient refractive index (GRIN) objective lenses. Aim: We present extended depth-of-field (EDoF) miniscope, which integrates an optimized thin and lightweight binary diffractive optical element (DOE) onto the GRIN lens of a miniscope to extend the DoF by 2.8× between twin foci in fixed scattering samples. Approach: We use a genetic algorithm that considers the GRIN lens' aberration and intensity loss from scattering in a Fourier optics-forward model to optimize a DOE and manufacture the DOE through single-step photolithography. We integrate the DOE into EDoF-Miniscope with a lateral accuracy of 70 µm to produce high-contrast signals without compromising the speed, spatial resolution, size, or weight. Results: We characterize the performance of EDoF-Miniscope across 5- and 10-µm fluorescent beads embedded in scattering phantoms and demonstrate that EDoF-Miniscope facilitates deeper interrogations of neuronal populations in a 100-µm-thick mouse brain sample and vessels in a whole mouse brain sample. Conclusions: Built from off-the-shelf components and augmented by a customizable DOE, we expect that this low-cost EDoF-Miniscope may find utility in a wide range of neural recording applications.

14.
Ann Otol Rhinol Laryngol ; 132(4): 431-439, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35656804

RESUMO

OBJECTIVES: Retrospectively analyze head and neck Langerhans Cell Histiocytosis at a rural tertiary referral center and compare results with previously published data. METHODS: Electronic health record review was performed from 2003 to 2019. Patients with biopsy proven LCH with primary head and neck involvement were included. Demographics, presentation, imaging characteristics, treatment modality, delay in diagnosis (DD, ≥60 days), and outcomes were analyzed and reported. RESULTS: Twenty-four patients were included. The most common presenting symptoms were otorrhea (n = 6) and scalp pain or swelling (n = 6). All patients had bony involvement. The most common site was facial or skull lesions (n = 20). Most skull lesions (75%) demonstrated CNS risk. Six patients were treated with primary surgery, 15 with primary chemotherapy, and 3 with surgery plus adjuvant chemotherapy. Nine patients experienced relapse of disease with median time to documented relapse of 11.4 months; all were treated with salvage chemotherapy to achieve complete remission (median follow-up: 72 months). Patients most likely to relapse were those with multisystem disease (5/7, 71.4%), temporal bone lesions (4/7, 57.1%), and DD (7/12, 58.3%). Of the 9 total patients who experienced relapse, 78% had a delay in diagnosis. CONCLUSIONS: LCH is a complex disease process in which diagnosis can be delayed if not considered in the differential. Within the head and neck, the skull, including isolated temporal bone involvement, is the most common site of involvement. Treatment modality does not appear to have an influence on relapse rates. Relapse was more likely to occur in the first year after treatment and close monitoring is required.


Assuntos
Cabeça , Histiocitose de Células de Langerhans , Humanos , Estudos Retrospectivos , Centros de Atenção Terciária , Cabeça/patologia , Histiocitose de Células de Langerhans/diagnóstico , Recidiva
15.
ArXiv ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36994164

RESUMO

Imaging through scattering is a pervasive and difficult problem in many biological applications. The high background and the exponentially attenuated target signals due to scattering fundamentally limits the imaging depth of fluorescence microscopy. Light-field systems are favorable for high-speed volumetric imaging, but the 2D-to-3D reconstruction is fundamentally ill-posed, and scattering exacerbates the condition of the inverse problem. Here, we develop a scattering simulator that models low-contrast target signals buried in heterogeneous strong background. We then train a deep neural network solely on synthetic data to descatter and reconstruct a 3D volume from a single-shot light-field measurement with low signal-to-background ratio (SBR). We apply this network to our previously developed Computational Miniature Mesoscope and demonstrate the robustness of our deep learning algorithm on scattering phantoms with different scattering conditions. The network can robustly reconstruct emitters in 3D with a 2D measurement of SBR as low as 1.05 and as deep as a scattering length. We analyze fundamental tradeoffs based on network design factors and out-of-distribution data that affect the deep learning model's generalizability to real experimental data. Broadly, we believe that our simulator-based deep learning approach can be applied to a wide range of imaging through scattering techniques where experimental paired training data is lacking.

16.
Front Endocrinol (Lausanne) ; 14: 1093332, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065756

RESUMO

Neuroendocrine prostate cancer (NEPC) is a highly aggressive subtype of prostate cancer. NEPC is characterized by the loss of androgen receptor (AR) signaling and transdifferentiation toward small-cell neuroendocrine (SCN) phenotypes, which results in resistance to AR-targeted therapy. NEPC resembles other SCN carcinomas clinically, histologically and in gene expression. Here, we leveraged SCN phenotype scores of various cancer cell lines and gene depletion screens from the Cancer Dependency Map (DepMap) to identify vulnerabilities in NEPC. We discovered ZBTB7A, a transcription factor, as a candidate promoting the progression of NEPC. Cancer cells with high SCN phenotype scores showed a strong dependency on RET kinase activity with a high correlation between RET and ZBTB7A dependencies in these cells. Utilizing informatic modeling of whole transcriptome sequencing data from patient samples, we identified distinct gene networking patterns of ZBTB7A in NEPC versus prostate adenocarcinoma. Specifically, we observed a robust association of ZBTB7A with genes promoting cell cycle progression, including apoptosis regulating genes. Silencing ZBTB7A in a NEPC cell line confirmed the dependency on ZBTB7A for cell growth via suppression of the G1/S transition in the cell cycle and induction of apoptosis. Collectively, our results highlight the oncogenic function of ZBTB7A in NEPC and emphasize the value of ZBTB7A as a promising therapeutic strategy for targeting NEPC tumors.


Assuntos
Tumores Neuroendócrinos , Neoplasias da Próstata , Humanos , Masculino , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Linhagem Celular Tumoral , Neoplasias da Próstata/patologia , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia
17.
bioRxiv ; 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37131649

RESUMO

The type II class of RAF inhibitors currently in clinical trials paradoxically activate BRAF at subsaturating concentrations. Activation is mediated by induction of BRAF dimers, but why activation rather than inhibition occurs remains unclear. Using biophysical methods tracking BRAF dimerization and conformation we built an allosteric model of inhibitor-induced dimerization that resolves the allosteric contributions of inhibitor binding to the two active sites of the dimer, revealing key differences between type I and type II RAF inhibitors. For type II inhibitors the allosteric coupling between inhibitor binding and BRAF dimerization is distributed asymmetrically across the two dimer binding sites, with binding to the first site dominating the allostery. This asymmetry results in efficient and selective induction of dimers with one inhibited and one catalytically active subunit. Our allosteric models quantitatively account for paradoxical activation data measured for 11 RAF inhibitors. Unlike type II inhibitors, type I inhibitors lack allosteric asymmetry and do not activate BRAF homodimers. Finally, NMR data reveal that BRAF homodimers are dynamically asymmetric with only one of the subunits locked in the active αC-in state. This provides a structural mechanism for how binding of only a single αC-in inhibitor molecule can induce potent BRAF dimerization and activation.

18.
Ann Otol Rhinol Laryngol ; 132(4): 403-409, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35607722

RESUMO

OBJECTIVE: Patient-provider communication is a major barrier to care, with some providers giving their personal phone number (PPN) to patients for increased accessibility. We investigated participant utilization of provider's PPN, its effect on participant satisfaction, provider's ability to predict abuse of this practice, and evolving provider perceptions. STUDY DESIGN: Prospective, randomized study. SETTING: Single institution, tertiary referral center. METHODS: During a 2-week period, otolaryngology patients were randomized to either receive their provider's PPN or not. Providers predicted the likelihood of abuse. All calls/texts were documented for 4 weeks. At the study's conclusion, participants were surveyed using Press Ganey metrics. Providers were surveyed before and after to assess their likelihood of providing patients with their PPN and its impact on work demands. RESULTS: Of the 507 participants enrolled, 266 were randomized to the phone number group (+PN). Of 44 calls/texts from 24 participants, 8 were considered inappropriate. Ten participants were predicted to abuse the PPN, but only one was accurately identified. Participants in the +PN group had a greater mean composite satisfaction score than the control group (4.8 vs 4.3; Welch's t-test, P < .0011). At the conclusion of the study, providers were more likely to share their PPN (Wilcoxon signed-rank test, P < .0313), and their perceived impact of this practice on workload was lower (Wilcoxon signed-rank test, P < .0469). CONCLUSION: This study demonstrates low patient utilization of provider PPNs, and poor provider predictive ability of patient abuse. Receipt of provider's PPN was associated with improved patient satisfaction.


Assuntos
Comunicação , Otolaringologia , Humanos , Estudos Prospectivos , Inquéritos e Questionários , Centros de Atenção Terciária , Satisfação do Paciente
19.
Sci Adv ; 9(26): eadg3444, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37390207

RESUMO

Spondweni virus (SPONV) is the closest known relative of Zika virus (ZIKV). SPONV pathogenesis resembles that of ZIKV in pregnant mice, and both viruses are transmitted by Aedes aegypti mosquitoes. We aimed to develop a translational model to further understand SPONV transmission and pathogenesis. We found that cynomolgus macaques (Macaca fascicularis) inoculated with ZIKV or SPONV were susceptible to ZIKV but resistant to SPONV infection. In contrast, rhesus macaques (Macaca mulatta) supported productive infection with both ZIKV and SPONV and developed robust neutralizing antibody responses. Crossover serial challenge in rhesus macaques revealed that SPONV immunity did not protect against ZIKV infection, whereas ZIKV immunity was fully protective against SPONV infection. These findings establish a viable model for future investigation into SPONV pathogenesis and suggest that the risk of SPONV emergence is low in areas with high ZIKV seroprevalence due to one-way cross-protection between ZIKV and SPONV.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Feminino , Gravidez , Animais , Camundongos , Macaca mulatta , Infecção por Zika virus/prevenção & controle , Estudos Soroepidemiológicos , Macaca fascicularis
20.
Sci Adv ; 8(16): eabj5227, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35452291

RESUMO

Here, we report that the LynB splice variant of the Src-family kinase Lyn exerts a dominant immunosuppressive function in vivo, whereas the LynA isoform is uniquely required to restrain autoimmunity in female mice. We used CRISPR-Cas9 gene editing to constrain lyn splicing and expression, generating single-isoform LynA knockout (LynAKO) or LynBKO mice. Autoimmune disease in total LynKO mice is characterized by production of antinuclear antibodies, glomerulonephritis, impaired B cell development, and overabundance of activated B cells and proinflammatory myeloid cells. Expression of LynA or LynB alone uncoupled the developmental phenotype from the autoimmune disease: B cell transitional populations were restored, but myeloid cells and differentiated B cells were dysregulated. These changes were isoform-specific, sexually dimorphic, and distinct from the complete LynKO. Despite the apparent differences in disease etiology and penetrance, loss of either LynA or LynB had the potential to induce severe autoimmune disease with parallels to human systemic lupus erythematosus (SLE).

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