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Dive into the research topics where Sprague W. Hazard is active.

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Featured researches published by Sprague W. Hazard.


Annals of the New York Academy of Sciences | 2010

Thymosin β4 enhances repair by organizing connective tissue and preventing the appearance of myofibroblasts

H. Paul Ehrlich; Sprague W. Hazard

Incisional wounds in rats treated locally with thymosin β4 (Tβ4) healed with minimal scaring and without loss in wound breaking strength. Treated wounds were significantly narrower in width. Polarized light microscopy treated wounds had superior organized collagen fibers, displaying a red birefringence, which is consistent with mature connective tissue. Control incisions had randomly organized collagen fibers, displaying green birefringence that is consistent with immature connective tissue. Immunohistology treated wounds had few myofibroblasts and fibroblasts with α smooth muscle actin (SMA) stained stress fibers. Polyvinyl alcohol sponge implants placed in subcutaneous pockets received either carrier or 100 μg of Tβ4 on days 2, 3, and 4. On day 14, treated implants revealed longer, thicker collagen fiber bundles with intense yellow‐red birefringence by polarized light microscopy. In controls, fine, thin collagen fiber bundles were arranged in random arrays with predominantly green birefringence. Controls contained mostly myofibroblasts, while few myofibroblasts appeared in Tβ4 treated implants. Electron microscopy confirmed both cell types and the degree of collagen fiber bundle organization. Our results demonstrate that Tβ4 treated wounds appear to mature earlier and heal with minimal scaring.


Journal of Surgical Oncology | 2011

Increased post‐operative complications with methylene blue versus lymphazurin in sentinel lymph node biopsies for skin cancers

Rogerio I. Neves; Brandon Reynolds; Sprague W. Hazard; Brian D. Saunders; Donald R. Mackay

Sentinel lymph node biopsy (SNLB) is the standard of care in staging of melanoma and other skin cancers. Early studies used lymphazurin (LZ) for SLNB. A national shortage of LZ promoted methylene blue (MB) as an alternate stain.


Journal of Genomics | 2017

Exploration of small RNA-seq data for small non-coding RNAs in Human Colorectal Cancer

Srinivas V. Koduru; Amit K. Tiwari; Sprague W. Hazard; Milind Mahajan; Dino J. Ravnic

Background: Improved healthcare and recent breakthroughs in technology have substantially reduced cancer mortality rates worldwide. Recent advancements in next-generation sequencing (NGS) have allowed genomic analysis of the human transcriptome. Now, using NGS we can further look into small non-coding regions of RNAs (sncRNAs) such as microRNAs (miRNAs), Piwi-interacting-RNAs (piRNAs), long non-coding RNAs (lncRNAs), and small nuclear/nucleolar RNAs (sn/snoRNAs) among others. Recent studies looking at sncRNAs indicate their role in important biological processes such as cancer progression and predict their role as biomarkers for disease diagnosis, prognosis, and therapy. Results: In the present study, we data mined publically available small RNA sequencing data from colorectal tissue samples of eight matched patients (benign, tumor, and metastasis) and remapped the data for various small RNA annotations. We identified aberrant expression of 13 miRNAs in tumor and metastasis specimens [tumor vs benign group (19 miRNAs) and metastasis vs benign group (38 miRNAs)] of which five were upregulated, and eight were downregulated, during disease progression. Pathway analysis of aberrantly expressed miRNAs showed that the majority of miRNAs involved in colon cancer were also involved in other cancers. Analysis of piRNAs revealed six to be over-expressed in the tumor vs benign cohort and 24 in the metastasis vs benign group. Only two piRNAs were shared between the two cohorts. Examining other types of small RNAs [sn/snoRNAs, mt_rRNA, miscRNA, nonsense mediated decay (NMD), and rRNAs] identified 15 sncRNAs in the tumor vs benign group and 104 in the metastasis vs benign group, with only four others being commonly expressed. Conclusion: In summary, our comprehensive analysis on publicly available small RNA-seq data identified multiple differentially expressed sncRNAs during colorectal cancer progression at different stages compared to normal colon tissue. We speculate that deciphering and validating the roles of sncRNAs may prove useful in colorectal cancer prognosis, diagnosis, and therapy.


Journal of Cancer | 2017

A comprehensive NGS data analysis of differentially regulated miRNAs, piRNAs, lncRNas and sn/snoRNAs in triple negative breast cancer

Srinivas V. Koduru; Amit K. Tiwari; Ashley N. Leberfinger; Sprague W. Hazard; Yuka Imamura Kawasawa; Milind Mahajan; Dino J. Ravnic

Cancer is the second leading cause of death in the United States and is a major public health concern worldwide. Basic, clinical and epidemiological research is leading to improved cancer detection, prevention, and outcomes. Recent technological advances have allowed unbiased and comprehensive screening of genome-wide gene expression. Small non-coding RNAs (sncRNAs) have been shown to play an important role in biological processes and could serve as a diagnostic, prognostic and therapeutic biomarker for specific diseases. Recent findings have begun to reveal and enhance our understanding of the complex architecture of sncRNA expression including miRNAs, piRNAs, lncRNAs, sn/snoRNAs and their relationships with biological systems. We used publicly available small RNA sequencing data that was derived from 24 triple negative breast cancers (TNBC) and 14 adjacent normal tissue samples to remap various types of sncRNAs. We found a total of 55 miRNAs were aberrantly expressed (p<0.005) in TNBC samples (8 miRNAs upregulated; 47 downregulated) compared to adjacent normal tissues whereas the original study reported only 25 novel miRs. In this study, we used pathway analysis of differentially expressed miRNAs which revealed TGF-beta signaling pathways to be profoundly affected in the TNBC samples. Furthermore, our comprehensive re-mapping strategy allowed us to discover a number of other differentially expressed sncRNAs including piRNAs, lncRNAs, sn/snoRNAs, rRNAs, miscRNAs and nonsense-mediated decay RNAs. We believe that our sncRNA analysis workflow is extremely comprehensive and suitable for discovery of novel sncRNAs changes, which may lead to the development of innovative diagnostic and therapeutic tools for TNBC.


Anesthesia & Analgesia | 2015

The evolution of perioperative transfusion testing and blood ordering

Marissa J. White; Sprague W. Hazard; Steven M. Frank; J.S. Boyd; Elizabeth C. Wick; Paul M. Ness; Aaron A. R. Tobian

The evolution of modern anesthesia and surgical practices has been accompanied by enhanced supportive procedures in blood banking and transfusion medicine. There is increased focus on the preparation and the use of blood components including, but not limited to, preventing unnecessary type and screen/crossmatch orders, decreasing the time required to provide compatible red blood cells (RBCs), and reducing the waste of limited blood and personnel resources. The aim of this review is to help the anesthesiologist and surgical staff identify patients at highest risk for surgical bleeding. In addition, this review examines how anesthesia and transfusion medicine can efficiently and safely allocate blood components for surgical patients who require transfusions. The following databases were searched: PubMed, EMBASE, Google Scholar, and the Cochrane Library from January 1970 through March 2014. Subsequent reference searches of retrieved articles were also assessed. Several innovations have drastically changed the procedures by which blood is ordered, inventoried, and the speed in which blood is delivered for patient care. Before entering an operating room, patient blood management provides guidance to clinicians about when and how to treat preoperative anemia and intra- and postoperative strategies to limit the patient’s exposure to blood components. Timely updates of the recommendations for blood orders (maximum surgical blood ordering schedule) have enhanced preoperative decision making regarding the appropriateness of the type and screen versus the type and crossmatch order. The updated maximum surgical blood ordering schedule reflects modern practices, such as laparoscopy, improved surgical techniques, and use of hemostatic agents resulting in a more streamlined process for ordering and obtaining RBCs. The electronic (computer) crossmatch and electronic remote blood issue have also dramatically reduced the amount of time required to obtain crossmatch-compatible RBCs when compared with the more traditional serologic crossmatch methods. These changes in blood banking methods have resulted in more efficient delivery of blood to surgical patients.


Annals of the New York Academy of Sciences | 2012

Thymosin β4 affecting the cytoskeleton organization of the myofibroblasts.

H. Paul Ehrlich; Sprague W. Hazard

In previous studies, granulation tissue from subcutaneous sponge implants in rats receiving thymosin β4, a 43‐amino acid actin‐binding protein that advances wound repair, produced the unexpected absence of myofibroblast populations, along with uniform organized collagen fibers within the newly deposited connective tissue matrix. This result raised the question of whether the Tβ4 effect on blocking fibroblasts transformation into myofibroblasts a direct or indirect one. We report here work in progress to address this question. When human dermal fibroblasts are plated at low density, upon reaching confluence, they all express α smooth muscle actin (αSMA) within their cytoplasmic stress fibers, morphologically defining them as myofibroblasts. Treating low‐density plated fibroblasts with Tβ4 prevents their expression of αSMA, as well as the generation an uneven distribution of microtubules within the cytoplasm. The speculation is that Tβ4 disruption of the distribution of microtubules alters the TGF‐β–Smad signaling pathway, thus blocking fibroblast transformation into myofibroblasts.


Current Surgery Reports | 2017

Adipose-Derived Stem Cells in Peripheral Nerve Regeneration

Ashley N. Leberfinger; Dino J. Ravnic; Russell Payne; Elias Rizk; Srinivas V. Koduru; Sprague W. Hazard

Purpose of the ReviewPeripheral nerve injuries are common, debilitating, and costly. The human body’s innate regenerative capacity is slow, and nerves are often misguided. The purpose of this article is to review a specific cellular, regenerative engineering technique that holds promise for the treatment of peripheral nerve injuries.Recent FindingsOver the past several decades, research has focused on the utilization of stem cells for peripheral nerve repair. More recently, stem cells collected from adipose tissue (adipose-derived stem cells or ADSCs) have gained traction due to their relative ease of collection and differentiation potential. Both undifferentiated and Schwann cell-like differentiated ADSCs have been used to seed conduits with variable results.SummaryTechnical and ethical issues surrounding stem cells’ self-expansion potential and genetic makeup exist. Ultimately, randomized control trials and FDA approval will be required before widespread clinical translation in the US is realized.


Medical Imaging 2003: Ultrasonic Imaging and Signal Processing | 2003

Spectral energy measurements of simulated microemboli of various sizes using a diffraction grating ultrasound probe

William J. Weiss; Sowmya G. Ballakur; Hoang Tran; Sprague W. Hazard; John Blebea

This study characterizes the Doppler signal from simulated microemboli of various sizes in blood mimicking fluid using spectral energy parameters. The goal of this research is to detect microemboli as a non-invasive diagnostic tool, or intra-operatively as a surgical aid. A dual beam diffraction-grating ultrasound probe operating at 10 MHz (Model Echoflow BVM-1, EchoCath, Inc., Princeton, NJ) was used with a flow phantom. Microemboli were polystyrene microspheres in 200 to 1000 micron diameters, in concentrations of 0.1, 0.5, and 1.0 per ml. Average flow velocities were 25, 50, 75, and 100 cm/sec. The distribution of peak values of the power spectrum at 2.5 msec windows was plotted over 15 seconds. The means of the distributions corresponding to the microspheres and background fluid were averaged for the four velocity conditions. Embolic peak spectral power ranged from approximately 12 to 25 dB relative to the background. A detection method based on these measurements is currently being developed.


northeast bioengineering conference | 2002

Detection of simulated microemboli using a diffraction grating ultrasound probe and spectral energy criteria

S.G. Ballakur; John Blebea; Sprague W. Hazard; R. Zickler; William J. Weiss

A new high frequency diffraction grating ultrasound probe was used to detect simulated microemboli under physiological (venous) flow conditions across different particle concentrations and velocities. Signal processing algorithms developed use spectral energy criteria and statistically determined decision criteria for the quantification of the detected particles.


Experimental and Molecular Pathology | 2011

Demonstrating collagen tendon fibril segments involvement in intrinsic tendon repair.

Sprague W. Hazard; Roland L. Myers; H. Paul Ehrlich

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Dino J. Ravnic

Brigham and Women's Hospital

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H. Paul Ehrlich

Penn State Milton S. Hershey Medical Center

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Ashley N. Leberfinger

Pennsylvania State University

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Milind Mahajan

Icahn School of Medicine at Mount Sinai

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Donald R. Mackay

Penn State Milton S. Hershey Medical Center

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John Blebea

Pennsylvania State University

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William J. Weiss

Penn State Milton S. Hershey Medical Center

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Yuka Imamura Kawasawa

Pennsylvania State University

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