University of California Medical Center

Sacramento, CA, United States

University of California Medical Center

Sacramento, CA, United States
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Abbey C.K.,University of California at Santa Barbara | Nosrateih A.,University of California at Davis | Nosrateih A.,University of California Medical Center | Sohl-Dickstein J.,Stanford University | And 3 more authors.
Medical Physics | Year: 2012

Purpose: Several studies have shown that the power spectrum of x-ray breast images is well described by a power-law at lower frequencies where anatomical variability dominates. However, an image generated from a Gaussian process with this spectrum is easily distinguished from an image of actual breast tissue by eye. This demonstrates that higher order non-Gaussian statistical properties of mammograms are readily accessible to the visual system. The authors' purpose is to quantify and characterize non-Gaussian statistical properties of breast images as influenced by processing of a digital mammogram, different imaging modalities, and breast density. Methods: To quantify non-Gaussian statistical properties, the authors consider histograms of filter responses from the interior of a breast image that have similar properties to receptive fields in the early visual system. They quantify departure from a Gaussian distribution by the relative entropy of the histogram compared to a best-fit Gaussian distribution. This entropy is normalized by the relative entropy of a best-fit Laplacian distribution into a measure they refer to as Laplacian fractional entropy (LFE). They test the LFE on a set of 26 patients recalled at screening for which they have available full-field digital mammography (FFDM), digital breast tomosynthesis (DBT), and dedicated breast CT (bCT) images as well as breast density scores and biopsy results. Results: A study of LFE in FFDM comparing the raw for-processing transmission data from the device to log-converted density estimates and the processed for-display data shows that processing mammographic image data enhances the non-Gaussian content of the image. A check of the methodology using a Gaussian process with a power-law power spectrum shows relatively little bias from the finite extent of the region of interests used. A second study comparing LFE across FFDM, DBT, and bCT modalities shows that each maximized the non-Gaussian content of the image for different ranges of spatial frequency. FFDM is optimal at high spatial frequencies (>0.7 mm-1), DBT is optimal at mid-range frequencies (0.3-0.7 mm-1), and bCT is optimal at low spatial frequency (0.3 mm-1). A third study of breast density in FFDM and bCT shows that LFE generally rises slightly going from the low-to moderate density, and then falls considerably at higher densities. Conclusions: Non-Gaussian statistical structure in breast images that is manifest in the responses of Gabor filters similar to receptive fields of the early visual system is dependent on how the image data are processed, the modality used to acquire the image, and the density of the breast tissue being imaged. Higher LFE corresponds with expected improvements from image processing and 3D imaging. © 2012 American Association of Physicists in Medicine.


Napoli E.,University of California at Davis | Song G.,University of California at Davis | Wong S.,University of California at Davis | Hagerman R.,University of California at Davis | And 2 more authors.
Cerebellum | Year: 2016

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late onset neurodegenerative disorder, characterized by tremors, ataxia, impaired coordination, and cognitive decline. While all FXTAS individuals are carriers of a 55–200 CGG expansion at the 5′-UTR of the fragile X mental retardation gene (FMR1), also known as premutation, not all carriers develop FXTAS symptoms and some display other types of psychological/emotional disorders (e.g., autism, anxiety). The goal of this study was to investigate whether the mitochondrial dysfunction previously observed in fibroblasts from older premutation individuals (>60 years) was already present in younger (17–48 years), non-FXTAS-affected carriers and to identify the type and severity of the bioenergetic deficit. Since FXTAS affects mostly males, while females account for a small part of the FXTAS-affected population displaying less severe symptoms, only fibroblasts from males were evaluated in this study. Based on polarographic and enzymatic measurements, a generalized OXPHOS deficit was noted accompanied by increases in the matrix biomarker citrate synthase, oxidative stress (as increased mtDNA copy number and deletions), and mitochondrial network disruption/disorganization. Some of the outcomes (ATP-linked oxygen uptake, coupling, citrate synthase activity, and mitochondrial network organization) strongly correlated with the extent of the CGG expansion, with more severe deficits observed in cell lines carrying higher CGG number. Furthermore, mitochondrial outcomes can identify endophenotypes among carriers and are robust predictors of the premutation diagnosis before the onset of FXTAS, with the potential to be used as markers of prognosis and/or as readouts of pharmacological interventions. © 2016 Springer Science+Business Media New York


Schellinger J.G.,University of California at Davis | Kudupudi A.,University of California Medical Center | Natarajan A.,University of California Medical Center | Du W.,Central Michigan University | And 2 more authors.
Organic and Biomolecular Chemistry | Year: 2012

Multivalent single chain variable fragments (scFv) show increased affinity to tumor-associated antigens compared to monovalent scFv and intact monoclonal antibodies (mAb). Multivalent constructs can be derived from self-associating or covalent scFv with covalent constructs offering improved in vivo and in vitro stability. Covalent attachment of scFv can be achieved using genetically engineered expression vectors that afford scFv with site specific cysteine functionality. Expression vectors for di-scFv-C wherein the cysteine is located in the center of two scFv have also been developed for attaching chemically reactive linkers. In the example illustrated here, the di-scFv-C is derived from a mAb directed against the MUC1 epitope, which is presented on cancer cells. To achieve multivalency, a chemical crosslinking strategy utilizing various azide and multi-alkyne functionalized polyethylene glycol (PEG) linkers was implemented. Conjugation was achieved by attachment of these linkers to the scFv thiol functionality. Chemoselective ligation was employed to covalently link different protein conjugates via copper(i) catalyzed azide alkyne 1,3-dipolar cycloaddition reaction (CuAAC) chemistry. Ligations were achieved in >70% yield using a specific set of linkers as determined by SDS-PAGE and densitometry. ELISA showed increased tumor binding of a tetravalent scFv providing a versatile chemical crosslinking strategy for construction of multivalent and bi-specific immunoconjugates that retain biological activity and have potential application in pre-targeted radioimmunotherapy and imaging. © 2012 The Royal Society of Chemistry.


Kalantar-Zadeh K.,University of California Medical Center | Kalantar-Zadeh K.,University of California at Los Angeles | Ikizler T.A.,Vanderbilt Medical Center
Journal of Renal Nutrition | Year: 2013

In individuals with chronic kidney disease, surrogates of protein-energy wasting, including a relatively low serum albumin and fat or muscle wasting, are by far the strongest death risk factor compared with any other condition. There are data to indicate that hypoalbuminemia responds to nutritional interventions, which may save lives in the long run. Monitored, in-center provision of high-protein meals and/or oral nutritional supplements during hemodialysis is a feasible, inexpensive, and patient-friendly strategy despite concerns such as postprandial hypotension, aspiration risk, infection control and hygiene, dialysis staff burden, diabetes and phosphorus control, and financial constraints. Adjunct pharmacologic therapies can be added, including appetite stimulators (megesterol, ghrelin, and mirtazapine), anabolic hormones (testosterone and growth factors), antimyostatin agents, and antioxidative and anti-inflammatory agents (pentoxiphylline and cytokine modulators), to increase efficiency of intradialytic food and oral supplementation, although adequate evidence is still lacking. If more severe hypoalbuminemia (<3.0 g/dL) not amenable to oral interventions prevails, or if a patient is not capable of enteral interventions (e.g., because of swallowing problems), then parenteral interventions such as intradialytic parenteral nutrition can be considered. Given the fact that meals and supplements during hemodialysis would require only a small fraction of the funds currently used for dialysis patients this is also an economically feasible strategy. © 2013 National Kidney Foundation, Inc.


Lin P.,Aesthetic and Plastic Surgery Institute | Cinat M.,University of California Medical Center | Cinat M.,University of California at Los Angeles
Journal of Burn Care and Research | Year: 2010

The authors report on a case of a healthy 29-year-old man with deep burns to his legs and feet totaling 4% TBSA who underwent successful skin grafting. He developed chronic pain in his graft site over his right ankle. Two and a half years after his graft had healed, he lost the graft because of herpes zoster infection. Zoster involving a skin graft is a rare entity, but its early recognition and treatment may prevent the loss of the graft. © 2010 by the American Burn Association.


PubMed | Fayetteville State University, University of Houston, University of Miami, Baylor College of Medicine and 8 more.
Type: Journal Article | Journal: Journal of clinical lipidology | Year: 2016

Bariatric procedures often improve lipid levels in patients with obesity. This 2-part scientific statement examines the potential lipid benefits of bariatric procedures and represents contributions from authors representing the National Lipid Association, American Society for Metabolic and Bariatric Surgery, and the Obesity Medicine Association. The foundation for this scientific statement was based on data published through June 2015. Part 1 of this 2-part scientific statement provides an overview of: (1) adipose tissue, cholesterol metabolism, and lipids; (2) bariatric procedures, cholesterol metabolism, and lipids; (3) endocrine factors relevant to lipid influx, synthesis, metabolism, and efflux; (4) immune factors relevant to lipid influx, synthesis, metabolism, and efflux; (5) bariatric procedures, bile acid metabolism, and lipids; and (6) bariatric procedures, intestinal microbiota, and lipids, with specific emphasis on how the alterations in the microbiome by bariatric procedures influence obesity, bile acids, and inflammation, which in turn, may all affect lipid levels. Included in part 2 of this comprehensive scientific statement will be a review of: (1) the importance of nutrients (fats, carbohydrates, and proteins) and their absorption on lipid levels; (2) the effects of bariatric procedures on gut hormones and lipid levels; (3) the effects of bariatric procedures on nonlipid cardiovascular disease risk factors; (4) the effects of bariatric procedures on lipid levels; (5) effects of bariatric procedures on cardiovascular disease; and finally (6) the potential lipid effects of vitamin, mineral, and trace element deficiencies that may occur after bariatric procedures. This document represents the executive summary of part 1.


PubMed | Fayetteville State University, University of Houston, University of Miami, Baylor College of Medicine and 8 more.
Type: Journal Article | Journal: Journal of clinical lipidology | Year: 2016

Bariatric procedures often improve lipid levels in patients with obesity. This 2 part scientific statement examines the potential lipid benefits of bariatric procedures and represents the contributions from authors representing the National Lipid Association, American Society for Metabolic and Bariatric Surgery, and the Obesity Medicine Association. The foundation for this scientific statement was based on published data through June 2015. Part 1 of this 2 part scientific statement provides an overview of: (1) adipose tissue, cholesterol metabolism, and lipids; (2) bariatric procedures, cholesterol metabolism, and lipids; (3) endocrine factors relevant to lipid influx, synthesis, metabolism, and efflux; (4) immune factors relevant to lipid influx, synthesis, metabolism, and efflux; (5) bariatric procedures, bile acid metabolism, and lipids; and (6) bariatric procedures, intestinal microbiota, and lipids, with specific emphasis on how the alterations in the microbiome by bariatric procedures influence obesity, bile acids, and inflammation, which in turn, may all affect lipid levels. Included in part 2 of this comprehensive scientific statement will be a review of (1) the importance of nutrients (fats, carbohydrates, and proteins) and their absorption on lipid levels; (2) the effects of bariatric procedures on gut hormones and lipid levels; (3) the effects of bariatric procedures on nonlipid cardiovascular disease (CVD) risk factors; (4) the effects of bariatric procedures on lipid levels; (5) effects of bariatric procedures on CVD; and finally, (6) the potential lipid effects of vitamin, mineral, and trace element deficiencies that may occur after bariatric procedures. This document represents the full report of part 1.


Macdonald K.,University of California Medical Center | Thomas M.L.,University of California Medical Center
Journal of Affective Disorders | Year: 2013

Background As the result of extensive translational and cross-disciplinary research, attachment theory is now a construct with significant neuropsychiatric traction. The correlation of attachment with other influential conceptual models (i.e. temperament and personality) is therefore of interest. Consequently, we explored how two attachment dimensions (attachment anxiety and attachment avoidance) correlated with measures of temperament and personality in 357 psychiatric outpatients. Methods We performed a retrospective review of four questionnaires (the Experiences in Close Relationship scale (ECR-R), Temperament and Character inventory (TCI), Temperament Evaluation of the Memphis, Pisa, Paris and San Diego questionnaire (TEMPS-A), and Personality Self-Portrait Questionnaire (PSQ)). Frequency measures and correlations were examined, as was the predictive value of attachment security for a personality disorder (PD). Results Significant, robust correlations were found between attachment anxiety and (1) several negative affective temperaments (dysthymic and cyclothymic); (2) several indices of personality pathology (low self-directedness (TCI), DSM-IV paranoid, borderline, histrionic, avoidant and dependent personality traits). Attachment avoidance had fewer large correlations. In an exploratory model, the negative predictive value of attachment security for a PD was 86%. Limitations Subjects were a relatively homogeneous subset of ambulatory psychiatric outpatients. PD diagnoses were via self-report. Conclusions Clinically, these findings highlight the significant overlap between attachment, affective temperament, and personality and support the value of attachment as a screen for PDs. More broadly, given our growing understanding of the neurobiology of attachment (i.e. links with the oxytocin system), these results raise interesting questions about underlying biological systems and psychiatric treatment. © 2013 Elsevier B.V.


Jones N.F.,University of California Medical Center | Dickinson B.P.,University of California Medical Center | Hansen S.L.,University of California Medical Center
Journal of Hand Surgery | Year: 2012

Radical resection of the entire ring finger metacarpal for a giant cell tumor resulted in a bony defect extending from the distal surface of the hamate to the proximal surface of the proximal phalanx. We reconstructed the metacarpal with a custom-contoured free fibular osteocutaneous flap and maintained motion at the new fibulophalangeal joint using a silicone arthroplasty. At 4.5 years postoperatively, the patient has shown no signs of recurrence of the giant cell tumor. The silicone arthroplasty has maintained 15°to 85°of motion at the new joint. Because of its similar shape to a metacarpal and because it allows faster bony healing compared with a nonvascularized fibular bone graft, a free vascularized fibular bone graft is an ideal candidate for reconstruction of extensive defects of the metacarpals, and placement of a silicone spacer in its distal medullary cavity can preserve motion at the new metacarpophalangeal joint. © 2012 American Society for Surgery of the Hand.


PubMed | University of California Medical Center
Type: Journal Article | Journal: Annals of vascular surgery | Year: 2014

Standard surveillance after endovascular abdominal aortic aneurysm repair (EVAR) consists of periodic computed tomographic arteriographies (CTAs) usually performed at postoperative months 1, 6, and 12, and then annually. This imaging regimen is expensive and exposes patients to the hazards of radiation and intravenous contrast. We hypothesized that a normal 1-month CTA after EVAR with no endoleak or other significant abnormality predicts a low rate of future complications, which would justify a reduction in frequency of subsequent CTAs.We identified 106 consecutive patients who underwent EVAR at a single hospital from 2003 to 2010 and reviewed all their CTAs. Fifteen patients for whom we could not review a postoperative CTA were excluded. Of the remaining 91 patients, 70 (76.9%) had no abnormality on their CTA at 1 month after EVAR. The medical records of these 70 patients were analyzed for subsequent complications and interventions related to EVAR.The mean patient follow-up was 3.4 2.1 years. Five of the 70 (7.1%) patients with a normal post-EVAR CTA developed late complications consisting of 1 type I endoleak, 3 type II endoleaks, and 1 case of endotension. Only the type I endoleak and one of the type II endoleaks met criteria for intervention, and in both cases, the endoleaks were discovered >3 years after EVAR. Log-rank test showed a statistically significant increased freedom from aneurysm sac expansion in patients with a normal compared with an abnormal 1-month CTA (P < 0.001).For patients who have a normal CTA with no endoleak 1 month after EVAR, it is reasonable to consider less-frequent CTA surveillance because no significant complications requiring intervention occurred before 3 years. This would decrease unnecessary CTAs and health care expenditures as well as minimize patient exposure to radiation and intravenous contrast.

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