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1.
Appl Opt ; 60(4): A222-A233, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690373

RESUMO

Assisted reproductive technologies seek to improve the success rate of pregnancies. Morphology scoring is a common approach to evaluate oocyte and embryo viability prior to embryo transfer in utero, but the efficacy of the method is low. We apply biodynamic imaging, based on dynamic light scattering and low-coherence digital holography, to assess the metabolic activity of oocytes and embryos. A biodynamic microscope, developed to image small and translucent biological specimens, is inserted into the bay of a commercial inverted microscope that can switch between conventional microscopy channels and biodynamic microscopy. We find intracellular Doppler spectral features that act as noninvasive proxies for embryo metabolic activity that may relate to embryo viability.


Assuntos
Embrião de Mamíferos/fisiologia , Holografia/instrumentação , Microscopia/instrumentação , Oócitos/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Embrião de Mamíferos/citologia , Feminino , Guanosina Trifosfato/metabolismo , Holografia/métodos , Humanos , Microscopia/métodos , Oócitos/citologia , Carne de Porco , Gravidez
2.
Biochem Biophys Res Commun ; 514(4): 1154-1159, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31103263

RESUMO

Intracellular Doppler spectroscopy is a form of low-coherence digital holography based upon Doppler detection of scattered light that measures drug response/resistance in tumor spheroids, xenografts, and clinical biopsies. Multidrug resistance (MDR) is one of the main causes of ineffective cancer treatment. One MDR mechanism is mediated by the MDR1 gene that encodes the drug efflux pump P-glycoprotein (Pgp). Overexpression of Pgp in some cancers is associated with poor chemotherapeutic response. This paper uses intracellular Doppler spectroscopy to detect Pgp-mediated changes to drug response in 3D tissues grown from an ovarian cancer cell line (SKOV3). The SKOV3 cell line was incrementally exposed to cisplatin to create a cell line with increased Pgp expression (SKOV3cis). Subsequently, MDR1 in a subset of these cells was silenced in SKOV3cis using shRNA to create a doxycycline inducible, Pgp-silenced cell line (SKOV3cis-sh). A specific Pgp inhibitor, zosuquidar, was used to study the effects of Pgp inhibition on the Doppler spectra. Increased drug sensitivity was observed with Pgp silencing or inhibition as determined by drug IC50s of paclitaxel-response of silenced Pgp and doxorubicin-response of inhibited Pgp, respectively. These results indicate that intracellular Doppler spectroscopy can detect changes in drug response due to silencing or inhibition of a single protein associated with drug resistance with important consequences for personalized medicine.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antibióticos Antineoplásicos/farmacologia , Dibenzocicloeptenos/farmacologia , Doxorrubicina/farmacologia , Fluxometria por Laser-Doppler , Neoplasias Ovarianas/tratamento farmacológico , Quinolinas/farmacologia , Esferoides Celulares/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antibióticos Antineoplásicos/análise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dibenzocicloeptenos/química , Doxorrubicina/análise , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Neoplasias Ovarianas/diagnóstico por imagem , Quinolinas/química , Células Tumorais Cultivadas
3.
J Opt Soc Am A Opt Image Sci Vis ; 36(4): 665-677, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044988

RESUMO

Intracellular dynamics in living tissue are dominated by active transport driven by bioenergetic processes far from thermal equilibrium. Intracellular constituents typically execute persistent walks. In the limit of long mean free paths, the persistent walks are ballistic, exhibiting a "Doppler edge" in light scattering fluctuation spectra. At shorter transport lengths, the fluctuations are described by lifetime-broadened Doppler spectra. Dynamic light scattering from transport in the ballistic, diffusive, or the crossover regimes is derived analytically, including the derivation of autocorrelation functions through a driven damped harmonic oscillator analog for light scattering from persistent walks. The theory is validated through Monte Carlo simulations. Experimental evidence for the Doppler edge in three-dimensional (3D) living tissue is obtained using biodynamic imaging based on low-coherence interferometry and digital holography.


Assuntos
Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Luz , Sobrevivência de Tecidos , Animais , Humanos , Imageamento Tridimensional , Método de Monte Carlo , Espalhamento de Radiação
4.
Appl Opt ; 54(1): A89-97, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25967027

RESUMO

Digital holography provides improved capabilities for imaging through dense tissue. Using a short-coherence source, the digital hologram recorded from backscattered light performs laser ranging that maintains fidelity of information acquired from depths much greater than possible by traditional imaging techniques. Biodynamic imaging (BDI) is a developing technology for live-tissue imaging of up to a millimeter in depth that uses the hologram intensity fluctuations as label-free image contrast and can study tissue behavior in native microenvironments. In this paper BDI is used to investigate the change in adhesion-dependent tissue response in 3D cultures. The results show that increasing density of cellular adhesions slows motion inside tissue and alters the response to cytoskeletal drugs. A clear signature of membrane fluctuations was observed in mid-frequencies (0.1-1 Hz) and was enhanced by the application of cytochalasin-D that degrades the actin cortex inside the cell membrane. This enhancement feature is only observed in tissues that have formed adhesions, because cell pellets initially do not show this signature, but develop this signature only after incubation enables adhesions to form.

5.
Front Oncol ; 14: 1429343, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39403334

RESUMO

Background: Esophageal cancer management lacks reliable response predictors to chemotherapy. In this study we evaluated the feasibility and accuracy of Biodynamic Imaging (BDI), a technology that employs digital holography as a rapid predictor of chemotherapy sensitivity in locoregional esophageal adenocarcinoma. Methods: Pre-treatment endoscopic pinch biopsies were collected from patients with esophageal adenocarcinoma during standard staging procedures. BDI analyzed the tumor samples and assessed in vitro chemotherapy sensitivity. BDI sensitivity predictions were compared to patients' pathological responses, the gold standard for determining clinical response, in the surgically treated subset (n=18). Result: BDI was feasible with timely tissue acquisition, collection, and processing in all 30 enrolled patients and successful BDI analysis in 28/29 (96%) eligible. BDI accurately predicted chemotherapy response in 13/18 (72.2%) patients using a classifier for complete, marked, and partial/no-response. BDI technology had 100% negative predictive value for complete pathological response hence identifying patients unlikely to respond to treatment. Conclusion: BDI technology can potentially predict patients' response to platinum chemotherapy. Additionally, this technology represents a promising step towards optimizing treatment strategies for esophageal adenocarcinoma patients by pre-emptively identifying non-responders to conventional platinum-based chemotherapy.

6.
Sci Rep ; 14(1): 2760, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332203

RESUMO

Nearly half of cancer patients who receive standard-of-care treatments fail to respond to their first-line chemotherapy, demonstrating the pressing need for improved methods to select personalized cancer therapies. Low-coherence digital holography has the potential to fill this need by performing dynamic contrast OCT on living cancer biopsies treated ex vivo with anti-cancer therapeutics. Fluctuation spectroscopy of dynamic light scattering under conditions of holographic phase stability captures ultra-low Doppler frequency shifts down to 10 mHz caused by light scattering from intracellular motions. In the comparative preclinical/clinical trials presented here, a two-species (human and canine) and two-cancer (esophageal carcinoma and B-cell lymphoma) analysis of spectral phenotypes identifies a set of drug response characteristics that span species and cancer type. Spatial heterogeneity across a centimeter-scale patient biopsy sample is assessed by measuring multiple millimeter-scale sub-samples. Improved predictive performance is achieved for chemoresistance profiling by identifying red-shifted sub-samples that may indicate impaired metabolism and removing them from the prediction analysis. These results show potential for using biodynamic imaging for personalized selection of cancer therapy.


Assuntos
Holografia , Neoplasias , Humanos , Animais , Cães , Difusão Dinâmica da Luz , Medicina de Precisão , Imageamento Quantitativo de Fase , Neoplasias/tratamento farmacológico , Holografia/métodos
7.
Appl Opt ; 52(1): A300-9, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23292406

RESUMO

Holographic optical coherence imaging is an en face form of optical coherence tomography that uses low-coherence digital holography as a coherence gate to select light from a chosen depth inside scattering tissue. By acquiring successive holograms at a high camera frame rate at a fixed depth, dynamic speckle provides information concerning dynamic light scattering from intracellular motility. Motility contrast imaging (MCI) uses living motion as a label-free and functional biomarker. MCI provides a new form of viability assay and also is applicable for proliferation and cytotoxicity assays. The results presented here demonstrate that low-coherence digital holography can extract viability information from biologically relevant three-dimensional (3D) tissue based on multicellular tumor spheroids by moving beyond the format of two-dimensional cell culture used for conventional high-content analysis. This paper also demonstrates the use of MCI for chemosensitivity assays on tumor exgrafts of excised ovarian cancer tumors responding to standard-of-care cisplatin chemotherapy. This ex vivo application extends the applicability of MCI beyond 3D tissue culture grown in vitro.


Assuntos
Bioensaio/instrumentação , Rastreamento de Células/instrumentação , Holografia/instrumentação , Microscopia/instrumentação , Neoplasias Experimentais/patologia , Processamento de Sinais Assistido por Computador/instrumentação , Tomografia de Coerência Óptica/instrumentação , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Desenho de Equipamento , Análise de Falha de Equipamento , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sobrevivência de Tecidos/efeitos dos fármacos
8.
Urol Oncol ; 41(6): 295.e9-295.e17, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36522279

RESUMO

BACKGROUND: Biodynamic signatures (temporal patterns of microscopic motion within a 3-dimensional tumor explant) offer phenomic biomarkers that are highly predictive for therapeutic response. OBJECTIVE: By utilizing motility contrast tomography, which provides a simple, fast assessment of motion patterns in living tissue, we evaluated the predictive accuracy of a biodynamic drug response classifier in muscle-invasive bladder cancer (MIBC) patients undergoing neoadjuvant chemotherapy (NAC). DESIGN, SETTING, AND PARTICIPANTS: One hundred five consecutive bladder cancer patients suspected of having MIBC were screened in a multi-institutional prospective observational study (NCT03739177) from July 2018 to June 2020, of whom, 30 completed NAC and radical cystectomy. INTERVENTION(S): Biodynamic signatures from treatment-naïve fresh bladder tumor specimens obtained after transurethral resection were measured in living tumor fragments challenged by standard-of-care cytotoxins. Patients received gemcitabine and cisplatin or dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin per institutional guidelines and were followed through radical cystectomy. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS: A 4-level classifier was developed to predict pathologic complete response (pCR) vs. incomplete response utilizing a one-left-out cross-validation protocol to minimize over-fitting. Area under the curve evaluated predictive utility. RESULTS: Thirty percent (9 of 30) achieved pCR. Utilizing the 4-level classifier, biodynamically "favored" (scoring ≥ 3) and "strongly favored" (scoring 4) regimens accurately predicted pCR at rates of 66.7% (4 of 6 patients) and 100% (4 of 4 patients), respectively. Biodynamically "favored" scores predicted pCR with 88% sensitivity and 95% negative predictive value, P < 0.0001. Only 5.0% (1 of 20 patients) achieved pCR from regimens scoring 1 or 2, indicating poor to no response from NAC. Area under the receiver operating curve was 96% (95% Confidence Interval: 79%-99%, P < 0.0001). Future direction involves validating this model prospectively. PRINCIPAL CONCLUSIONS: Biodynamic scoring accurately predicts response in MIBC patients receiving NAC and holds promise to substantially improve the scope of appropriate management intervention.


Assuntos
Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/uso terapêutico , Terapia Neoadjuvante/efeitos adversos , Estudos Prospectivos , Neoplasias da Bexiga Urinária/patologia , Cistectomia/métodos , Músculos/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Invasividade Neoplásica , Estudos Retrospectivos
9.
Calcif Tissue Int ; 90(3): 202-10, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22249525

RESUMO

Differences in the binding affinities of bisphosphonates for bone mineral have been proposed to determine their localizations and duration of action within bone. The main objective of this study was to test the hypothesis that mineral binding affinity affects bisphosphonate distribution at the basic multicellular unit (BMU) level within both cortical and cancellous bone. To accomplish this objective, skeletally mature female rabbits (n = 8) were injected simultaneously with both low- and high-affinity bisphosphonate analogs bound to different fluorophores. Skeletal distribution was assessed in the rib, tibia, and vertebra using confocal microscopy. The staining intensity ratio between osteocytes contained within the cement line of newly formed rib osteons or within the reversal line of hemiosteons in vertebral trabeculae compared to osteocytes outside the cement/reversal line was greater for the high-affinity compared to the low-affinity compound. This indicates that the low-affinity compound distributes more equally across the cement/reversal line compared to a high-affinity compound, which concentrates mostly near surfaces. These data, from an animal model that undergoes intracortical remodeling similar to humans, demonstrate that the affinity of bisphosphonates for the bone determines the reach of the drugs in both cortical and cancellous bone.


Assuntos
Conservadores da Densidade Óssea/farmacocinética , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Difosfonatos/farmacocinética , Animais , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Ligação Competitiva/efeitos dos fármacos , Ligação Competitiva/fisiologia , Remodelação Óssea/fisiologia , Osso e Ossos/citologia , Feminino , Ósteon/citologia , Ósteon/efeitos dos fármacos , Ósteon/metabolismo , Osteócitos/citologia , Osteócitos/efeitos dos fármacos , Osteócitos/metabolismo , Osteoporose/tratamento farmacológico , Coelhos , Distribuição Tecidual/fisiologia
10.
J Biomed Opt ; 26(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33783149

RESUMO

SIGNIFICANCE: Common-path interferometers have the advantage of producing ultrastable interferometric fringes compared with conventional interferometers, such as Michelson or Mach-Zehnder that are sensitive to environmental instabilities. Isolating interferometric measurements from mechanical disturbances is important in biodynamic imaging because Doppler spectroscopy of intracellular dynamics requires extreme stability for phase-sensitive interferometric detection to capture fluctuation frequencies down to 10 mHz. AIM: The aim of this study was to demonstrate that Doppler spectra produced from a common-path interferometer using a grating and a spatial filter (SF) are comparable to, and more stable than, spectra from conventional biodynamic imaging. APPROACH: A common-path interferometer using a holographic diffraction grating and an SF was employed with a low-coherence source. Simulations evaluated the spatial resolution. DLD-1 (human colon adenocarcinoma) spheroids were used as living target tissue samples. Power spectra under external vibrations and drug-response spectrograms were compared between common-path and Fourier-domain holographic systems. RESULTS: The common-path holography configuration shows enhanced interferometric stability against mechanical vibrations through common-mode rejection while maintaining sensitivity to Doppler frequency fluctuations caused by intracellular motions. CONCLUSIONS: A common-path interferometer using a grating and an SF can provide enhanced interferometric stability in tissue-dynamics spectroscopy for drug screening assays.


Assuntos
Holografia , Humanos , Interferometria , Análise Espectral
11.
Commun Biol ; 4(1): 178, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568744

RESUMO

Living 3D in vitro tissue cultures, grown from immortalized cell lines, act as living sentinels as pathogenic bacteria invade the tissue. The infection is reported through changes in the intracellular dynamics of the sentinel cells caused by the disruption of normal cellular function by the infecting bacteria. Here, the Doppler imaging of infected sentinels shows the dynamic characteristics of infections. Invasive Salmonella enterica serovar Enteritidis and Listeria monocytogenes penetrate through multicellular tumor spheroids, while non-invasive strains of Escherichia coli and Listeria innocua remain isolated outside the cells, generating different Doppler signatures. Phase distributions caused by intracellular transport display Lévy statistics, introducing a Lévy-alpha spectroscopy of bacterial invasion. Antibiotic treatment of infected spheroids, monitored through time-dependent Doppler shifts, can distinguish drug-resistant relative to non-resistant strains. This use of intracellular Doppler spectroscopy of living tissue sentinels opens a new class of microbial assay with potential importance for studying the emergence of antibiotic resistance.


Assuntos
Bactérias/patogenicidade , Infecções Bacterianas/diagnóstico , Imagem Óptica , Imagem com Lapso de Tempo , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Linhagem Celular Tumoral , Efeito Doppler , Farmacorresistência Bacteriana , Diagnóstico Precoce , Humanos , Valor Preditivo dos Testes , Análise Espectral , Esferoides Celulares , Fatores de Tempo
12.
Vet Med Sci ; 7(3): 665-673, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33369129

RESUMO

BACKGROUND: Neutropenia is the most common dose-limiting side effect of cytotoxic chemotherapy in cancer-bearing dogs. Biodynamic imaging (BDI) is a functional imaging technology that measures dynamic light scattering from living, three-dimensional tissues to characterize intracellular motion within those tissues. Previous studies have associated BDI biomarkers with tumour sensitivity to chemotherapy agents in dogs with naturally occurring cancer. We hypothesized that BDI, performed ex vivo on bone marrow aspirate samples, would identify dynamic biomarkers associated with the occurrence of specific degrees of neutropenia in tumour-bearing dogs receiving doxorubicin chemotherapy. MATERIALS AND METHODS: Bone marrow aspirates were collected from 10 dogs with naturally occurring cancers prior to initiation of doxorubicin treatment. BDI was performed on bone marrow samples treated ex vivo with doxorubicin at 0.1, 1, 10 and 100 µM along with 0.1% DMSO as a control. Dogs then were treated with doxorubicin (30 mg/m2 , intravenously). Peripheral blood neutrophil counts were obtained on the day of treatment and again 7 days later. Receiver operating characteristic curves identified provisional breakpoints for BDI biomarkers that correlated with specific changes in neutrophil counts between the two time points. RESULTS: Provisional breakpoints for several BDI biomarkers were identified, specifying dogs with the largest proportionate change in neutrophils and with neutropenia that was grade 2 or higher following doxorubicin treatment. CONCLUSIONS: Biodynamic imaging of bone marrow aspirates may identify those dogs at greater risk for neutropenia following doxorubicin chemotherapy. This approach may be useful for pre-emptively modifying chemotherapy dosing in dogs to avoid unacceptable side effects.


Assuntos
Antineoplásicos/efeitos adversos , Biomarcadores Tumorais/análise , Medula Óssea/química , Doenças do Cão/metabolismo , Neoplasias/veterinária , Neutropenia/veterinária , Animais , Doenças do Cão/induzido quimicamente , Cães , Neoplasias/metabolismo , Neutropenia/induzido quimicamente
13.
Sci Rep ; 10(1): 17354, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060663

RESUMO

Development of an assay to predict response to chemotherapy has remained an elusive goal in cancer research. We report a phenotypic chemosensitivity assay for epithelial ovarian cancer based on Doppler spectroscopy of infrared light scattered from intracellular motions in living three-dimensional tumor biopsy tissue measured in vitro. The study analyzed biospecimens from 20 human patients with epithelial ovarian cancer. Matched primary and metastatic tumor tissues were collected for 3 patients, and an additional 3 patients provided only metastatic tissues. Doppler fluctuation spectra were obtained using full-field optical coherence tomography through off-axis digital holography. Frequencies in the range from 10 mHz to 10 Hz are sensitive to changes in intracellular dynamics caused by platinum-based chemotherapy. Metastatic tumor tissues were found to display a biodynamic phenotype that was similar to primary tissue from patients who had poor clinical outcomes. The biodynamic phenotypic profile correctly classified 90% [88-91% c.i.] of the patients when the metastatic samples were characterized as having a chemoresistant phenotype. This work suggests that Doppler profiling of tissue response to chemotherapy has the potential to predict patient clinical outcomes based on primary, but not metastatic, tumor tissue.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Ultrassonografia Doppler/métodos , Carcinoma Epitelial do Ovário/diagnóstico por imagem , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico por imagem , Fenótipo , Microambiente Tumoral
14.
J Biomed Opt ; 25(9)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32964703

RESUMO

SIGNIFICANCE: Tumor heterogeneity poses a challenge for the chemotherapeutic treatment of cancer. Tissue dynamics spectroscopy captures dynamic contrast and can capture the response of living tissue to applied therapeutics, but the current analysis averages over the complicated spatial response of living biopsy samples. AIM: To develop tissue dynamics spectroscopic imaging (TDSI) to map the heterogeneous spatial response of tumor tissue to anticancer drugs. APPROACH: TDSI is applied to tumor spheroids grown from cell lines and to ex vivo living esophageal biopsy samples. Doppler fluctuation spectroscopy is performed on a voxel basis to extract spatial maps of biodynamic biomarkers. Functional images and bivariate spatial maps are produced using a bivariate color merge to represent the spatial distribution of pairs of signed drug-response biodynamic biomarkers. RESULTS: We have mapped the spatial variability of drug responses within biopsies and have tracked sample-to-sample variability. Sample heterogeneity observed in the biodynamic maps is associated with histological heterogeneity observed using inverted selective-plane illumination microscopy. CONCLUSION: We have demonstrated the utility of TDSI as a functional imaging method to measure tumor heterogeneity and its potential for use in drug-response profiling.


Assuntos
Antineoplásicos , Neoplasias , Diagnóstico por Imagem , Humanos , Neoplasias/diagnóstico por imagem , Análise Espectral
15.
Nurs Econ ; 26(2): 85-105, 121, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18524374

RESUMO

OBJECTIVE: To forecast the shortage of registered nurses (RNs) of the 24 Primary Metropolitan Statistical Areas (PMSA) and Metropolitan Statistical Areas (MSA) in California. BACKGROUND: A nursing shortage prevails nationally and is most serious in the state of California. Successful interventions in the alleviation of the RN shortage will require effective resource allocation and academic program development in various regions throughout the state. While various published studies have focused on nursing workforce development at the state and even regional levels, there are no studies focused on identifying RN shortages at the PMSA or MSA (P/MSA) level. In this report, a forecasting model is developed to systematically analyze the future supply and demand of the RN workforce within each California P/MSA. METHODS: Using accessible public databases, forecasting models were constructed to project the demand and supply of RN jobs in California P/MSAs. In the demand model, population age and size were used as determinants of regionally required RN jobs. In the RN jobs (supply) model, a region's supply of RNs was the net sum of factors increasing and decreasing the regional presence of RN jobs, including RN graduations, migration, and aging of the RN workforce. The combination of these supply and demand models was used to produce regional RN shortage forecasts for future years. RESULTS: Almost all regions exhibited growing shortages by 2020 at rates ranging from 3% to 600%. Using a modified version of the grading rubric of the California Regional Registered Nurse Workforce Report Card (Lin, Lee, Juraschek, & Jones, 2006), only two regions will receive a grade above "C" in 2020. The number of "F" grades will grow to nine. CONCLUSIONS: California has the lowest RN ratio in the United States (Fletcher, Guzley, Barnhill, & Philhour, 2004; Health Resources and Services Administration, 2004a) and this RN workforce forecasting model shows that over the next 15 years, the majority of P/MSAs in California will have increasing RN shortages. This analysis has significant policy implications including the need to create specific plans to mitigate the effect of the California shortage.


Assuntos
Enfermeiras e Enfermeiros/provisão & distribuição , California , Previsões , Necessidades e Demandas de Serviços de Saúde , Modelos Teóricos , Dinâmica Populacional
16.
Biomed Opt Express ; 9(5): 2214-2228, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29760982

RESUMO

Biodynamic digital holography was used to obtain phenotypic profiles of canine non-Hodgkin B-cell lymphoma biopsies treated with standard-of-care chemotherapy. Biodynamic signatures from the living 3D tissues were extracted using fluctuation spectroscopy from intracellular Doppler light scattering in response to the molecular mechanisms of action of therapeutic drugs that modify a range of internal cellular motions. The standard-of-care to treat B-cell lymphoma in both humans and dogs is a combination CHOP therapy that consists of doxorubicin, prednisolone, cyclophosphamide and vincristine. The proportion of dogs experiencing durable cancer remission following CHOP chemotherapy was 68%, with 13 out of 19 dogs responding favorably to therapy and 6 dogs failing to have progression-free survival times greater than 100 days. Biodynamic signatures were found that correlate with inferior survival times, and biomarker selection was optimized to identify specific Doppler signatures related to chemoresistance. A machine learning classifier was constructed based on feature vector correlations and linear separability in high-dimensional feature space. Hold-out validation predicted patient response to therapy with 84% accuracy. These results point to the potential for biodynamic profiling to contribute to personalized medicine by aiding the selection of chemotherapy for cancer patients.

17.
Opt Express ; 15(21): 14057-64, 2007 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-19550678

RESUMO

Microscopic imaging of cellular motility has recently advanced from two dimensions to three dimensions for applications in drug development. However, significant degradation in resolution occurs with increasing imaging depth, limiting access to motility information from deep inside the sample. Here, digital holographic optical coherence imaging is adapted to allow visualization of motility in tissue at depths inaccessible to conventional motility assay approaches. This method tracks the effect of cytoskeletal anti-cancer drugs on tissue inside its natural three-dimensional environment using time-course measurement of motility within tumor tissue.

18.
J Biomed Opt ; 22(1): 16007, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28301634

RESUMO

Three-dimensional (3-D) tissue culture represents a more biologically relevant environment for testing new drugs compared to conventional two-dimensional cancer cell culture models. Biodynamic imaging is a high-content 3-D optical imaging technology based on low-coherence interferometry and digital holography that uses dynamic speckle as high-content image contrast to probe deep inside 3-D tissue. Speckle contrast is shown to be a scaling function of the acquisition time relative to the persistence time of intracellular transport and hence provides a measure of cellular activity. Cellular responses of 3-D multicellular spheroids to paclitaxel are compared among three different growth techniques: rotating bioreactor (BR), hanging-drop (HD), and nonadherent (U-bottom, UB) plate spheroids, compared with ex vivo living tissues. HD spheroids have the most homogeneous tissue, whereas BR spheroids display large sample-to-sample variability as well as spatial heterogeneity. The responses of BR-grown tumor spheroids to paclitaxel are more similar to those of ex vivo biopsies than the responses of spheroids grown using HD or plate methods. The rate of mitosis inhibition by application of taxol is measured through tissue dynamics spectroscopic imaging, demonstrating the ability to monitor antimitotic chemotherapy. These results illustrate the potential use of low-coherence digital holography for 3-D pharmaceutical screening applications.


Assuntos
Holografia/métodos , Imagem Óptica/métodos , Técnicas de Cultura de Tecidos/métodos , Antineoplásicos Fitogênicos/farmacologia , Técnicas de Cultura de Células , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Neoplasias , Paclitaxel/farmacologia , Fenótipo , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/ultraestrutura
19.
Sci Rep ; 6: 18821, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26732545

RESUMO

Three-dimensional (3D) tissue cultures are replacing conventional two-dimensional (2D) cultures for applications in cancer drug development. However, direct comparisons of in vitro 3D models relative to in vivo models derived from the same cell lines have not been reported because of the lack of sensitive optical probes that can extract high-content information from deep inside living tissue. Here we report the use of biodynamic imaging (BDI) to measure response to platinum in 3D living tissue. BDI combines low-coherence digital holography with intracellular Doppler spectroscopy to study tumor drug response. Human ovarian cancer cell lines were grown either in vitro as 3D multicellular monoculture spheroids or as xenografts in nude mice. Fragments of xenografts grown in vivo in nude mice from a platinum-sensitive human ovarian cell line showed rapid and dramatic signatures of induced cell death when exposed to platinum ex vivo, while the corresponding 3D multicellular spheroids grown in vitro showed negligible response. The differences in drug response between in vivo and in vitro growth have important implications for predicting chemotherapeutic response using tumor biopsies from patients or patient-derived xenografts.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Imagem Molecular/métodos , Neoplasias Ovarianas/metabolismo , Platina/farmacologia , Ultrassonografia Doppler/métodos , Animais , Biomarcadores , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Camundongos , Células Tumorais Cultivadas
20.
J Nutr Biochem ; 16(8): 500-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16043032

RESUMO

Inability to control collagen formation in vital organs (e.g., fibrosis) or stimulate healthy collagen production (CP) in connective tissues (e.g., ligaments) is a major cause of death and disability. This study tested the hypothesis that arachidonic acid (AA) and eicosapentaenoic acid (EPA) influenced CP in 3T3-Swiss fibroblasts by altering gene expression in the nuclear factor-kappa B (NF-kappaB) pathway. 3T3-Swiss fibroblasts were grown in medium containing either AA or EPA. Lipopolysaccharide (LPS) was used to activate NF-kappaB, and parthenolide was used to block it. Cells treated with EPA had increased expression of genes in the NF-kappaB pathway when exposed to LPS and also produced more collagen. Parthenolide blocked NF-kappaB activation to a greater extent in EPA-treated cells and also decreased CP induced by NF-kappaB activation. Genes in the NF-kappaB signaling pathway that had increased expression in EPA-treated cells included the toll-like receptor 4 (Tlr4), adaptor proteins [TNF receptor-associated factor 6 (Traf6), myeloid differentiation primary response gene 88], signal transduction kinases (NF-kappaB-inducing kinase, inhibitors of kappa light polypeptide gene enhancer isoforms), inhibitor protein (I-kappaB alpha chain), transcription factors (nuclear factor of kappa light chain gene enhancer, (p)105 and NF-kappaB subunit p100), DNA binding proteins (cAMP response element binding protein) and response genes known to affect CP [interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), monocyte chemotactic protein-1]. This study raises the possibility that fatty acids may be used as adjuvants in combination with other therapies (e.g., selective targeting of the NF-kappaB pathway) to control collagen formation.


Assuntos
Ácido Araquidônico/farmacologia , Colágeno/biossíntese , Ácido Eicosapentaenoico/farmacologia , Expressão Gênica/efeitos dos fármacos , NF-kappa B/biossíntese , Animais , Perfilação da Expressão Gênica , Lipopolissacarídeos/farmacologia , Camundongos , Sesquiterpenos/farmacologia , Células Swiss 3T3
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