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Andrew M. Hoffman

Bio: Andrew M. Hoffman is an academic researcher from Tufts University. The author has contributed to research in topics: Mesenchymal stem cell & Bronchoalveolar lavage. The author has an hindex of 34, co-authored 123 publications receiving 3916 citations. Previous affiliations of Andrew M. Hoffman include Ontario Veterinary College & University of Guelph.


Papers
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Patent
09 Sep 2002
TL;DR: In this paper, a system for measuring respiratory function of living organisms is proposed. But, the system is not suitable for monitoring patients with compromised respiratory function and it is only suitable for continuous or intermittently monitoring patients.
Abstract: The present invention relates to a system for measuring respiratory function of living organisms. More particularly, signals indicative of the change in lung volume, defined as active and passive work, required to breathe and the airflow through the respiratory system of the living organism are obtained and processed as waveforms to provide a signal indicative of the respiratory restriction. The methods of the present invention measure clinical forms of airway obstruction, airway reactivity and lung volume and may be used to continuously or intermittently monitor patients with compromised respiratory function. In a preferred embodiment, a head-out, breath in respiratory plethysmograph system provides the signals indicative of change in lung volume as related to pressure changes in a chamber. Further, flowmetric variables are generated that provide a characterization of airway obstructions.

242 citations

Journal ArticleDOI
TL;DR: The purpose of this consensus statement is to provide a review of current knowledge and opinions concerning inflammatory airway disease and to help practitioners differentiate IAD from heaves (or recurrent airway obstruction; RAO) and other inflammatory respiratory diseases of horses.
Abstract: The purpose of this consensus statement is to provide a review of current knowledge and opinions concerning inflammatory airway disease (IAD) and to help practitioners differentiate IAD from heaves (or recurrent airway obstruction; RAO) and other inflammatory respiratory diseases of horses.

193 citations

Journal ArticleDOI
TL;DR: In this article, the authors demonstrate potent xenogeneic effects of conditioned media (CM) and extracellular vesicles (EVs) released by mesenchymal stromal cells (MSCs) derived from bone marrow and other sources are as effective as the MSCs themselves in mitigating inflammation and injury.
Abstract: An increasing number of studies demonstrate that administration of either conditioned media (CM) or extracellular vesicles (EVs) released by mesenchymal stromal cells (MSCs) derived from bone marrow and other sources are as effective as the MSCs themselves in mitigating inflammation and injury. The goal of the current study was to determine whether xenogeneic administration of CM or EVs from human bone marrow-derived MSCs would be effective in a model of mixed Th2/Th17, neutrophilic-mediated allergic airway inflammation, reflective of severe refractory asthma, induced by repeated mucosal exposure to Aspergillus hyphal extract (AHE) in immunocompetent C57Bl/6 mice. Systemic administration of both CM and EVs isolated from human and murine MSCs, but not human lung fibroblasts, at the onset of antigen challenge in previously sensitized mice significantly ameliorated the AHE-provoked increases in airway hyperreactivity (AHR), lung inflammation, and the antigen-specific CD4 T-cell Th2 and Th17 phenotype. Notably, both CM and EVs from human MSCs (hMSCs) were generally more potent than those from mouse MSCs (mMSCs) in most of the outcome measures. The weak cross-linking agent 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride was found to inhibit release of both soluble mediators and EVs, fully negating effects of systemically administered hMSCs but only partly inhibited the ameliorating effects of mMSCs. These results demonstrate potent xenogeneic effects of CM and EVs from hMSCs in an immunocompetent mouse model of allergic airway inflammation and they also show differences in mechanisms of action of hMSCs versus mMSCs to mitigate AHR and lung inflammation in this model.

175 citations

Journal ArticleDOI
TL;DR: Scar tissue, generated by BLVR, replaced hyperinflated lung, reduced overall lung volume, and improved respiratory function safely and consistently, and appears safe and effective enough to justify a trial in humans.
Abstract: Bronchoscopic lung volume reduction (BLVR), a minimally invasive was based on the simple concept that collapse of target reprocedure based on tissue engineering principles, was performed in gions could be initiated using a washout solution to disrupt six sheep with papain-induced experimental emphysema (EMPH). surfactant function, and be maintained with a biocompatible Physiologic measurements, at baseline, after generation of EMPH, “tissue sealant” to prevent re-expansion. The concept was and at 3 and 9 weeks after BLVR, included lung volumes, diffusing tested using a sheep model of EMPH, in which lung zones capacity (DLCO), pressure–volume relationships for the lung and chest supplied by 5 to 7 mm airways were blocked, collapsed, and wall , pleural pressures generated during active respiratory muscle filled with a fibrin hydrogel sealant. This “mechanical” apcontraction, lung resistance and dynamic elastance. The animal proach to bronchoscopic volume reduction produced atelecmodel displayed hyperinflation (change in total lung capacity8%; tasis with subsequent scarring in 55% of the treated sites, change in residual volume 66%), reduced DLCO (21%), and ele- confirming the feasibility of BLVR. However, the procedure vated airway resistance (76%) that resembled advanced human was associated with a 15% incidence of sterile abscess formaEMPH. BLVR was well tolerated without complications, and it re- tion (10). Although physiologic benefits in successfully duced lung volumes (change in total lung capacity 16%; change treated sheep were comparable with those of a 20 to 25% in residual volume 55%) in a pattern that resulted in significant surgical volume reduction, the high failure rate, and unacimprovements in vital capacity (10%). At autopsy, well-organized, ceptably high incidence of abscess formation rendered this peripheral scars associated with tissue contraction were observed approach to BLVR unacceptable for clinical use. at 33 of the 36 (91%) treated sites. There was no evidence of infection, abscess, or granuloma formation, or allergic reaction. Scar Recently completed cell culture and large animal studies tissue, generated by BLVR, replaced hyperinflated lung, reduced suggest that to improve the effectiveness and safety of BLVR, overall lung volume, and improved respiratory function safely and consideration of biologic as well as mechanical responses consistently. The BLVR technology employed in this study addresses are necessary (11). Successful BLVR essentially requires a the limitations identified in our prior attempt at BLVR therapy and remodeling process whereby damaged, hyperinflated lung is appears safe and effective enough to justify a trial in humans. transformed into contracted scar by delivering reagents that alter the biologic environment at specific target sites. Al

149 citations

Journal ArticleDOI
TL;DR: Companion animals with naturally occurring diseases analogous to human conditions can be recruited into clinical trials and provide realistic insight into feasibility, safety, and biologic activity of novel stem cell therapies, however, improvements in the rigor of manufacturing, study design, and regulatory compliance will be needed to better utilize these models.
Abstract: Studies to evaluate the therapeutic potential of stem cells in humans would benefit from more realistic animal models. In veterinary medicine, companion animals naturally develop many diseases that resemble human conditions, therefore, representing a novel source of preclinical models. To understand how companion animal disease models are being studied for this purpose, we reviewed the literature between 2008 and 2015 for reports on stem cell therapies in dogs and cats, excluding laboratory animals, induced disease models, cancer, and case reports. Disease models included osteoarthritis, intervertebral disc degeneration, dilated cardiomyopathy, inflammatory bowel diseases, Crohn's fistulas, meningoencephalomyelitis (multiple sclerosis-like), keratoconjunctivitis sicca (Sjogren's syndrome-like), atopic dermatitis, and chronic (end-stage) kidney disease. Stem cells evaluated in these studies included mesenchymal stem-stromal cells (MSC, 17/19 trials), olfactory ensheathing cells (OEC, 1 trial), or neural lineage cells derived from bone marrow MSC (1 trial), and 16/19 studies were performed in dogs. The MSC studies (13/17) used adipose tissue-derived MSC from either allogeneic (8/13) or autologous (5/13) sources. The majority of studies were open label, uncontrolled studies. Endpoints and protocols were feasible, and the stem cell therapies were reportedly safe and elicited beneficial patient responses in all but two of the trials. In conclusion, companion animals with naturally occurring diseases analogous to human conditions can be recruited into clinical trials and provide realistic insight into feasibility, safety, and biologic activity of novel stem cell therapies. However, improvements in the rigor of manufacturing, study design, and regulatory compliance will be needed to better utilize these models. Stem Cells 2016;34:1709-1729.

128 citations


Cited by
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Journal ArticleDOI
Clotilde Théry1, Kenneth W. Witwer2, Elena Aikawa3, María José Alcaraz4  +414 moreInstitutions (209)
TL;DR: The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities, and a checklist is provided with summaries of key points.
Abstract: The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points.

5,988 citations

Journal ArticleDOI
TL;DR: The biochemical functions and the importance of the mineral elements in health and disease conditions of humans, animals and plants are reviewed as this will assist in the prevention of nutrition-related diseases and maintenance of good health for humans and animals that depend on plants for food.
Abstract: Minerals are inorganic nutrients, usually required in small amounts from less than 1 to 2500 mg per day, depending on the mineral. As with vitamins and other essential food nutrients, mineral requirements vary with animal species. For example, humans and other vertebrates need large amounts of calcium for construction and maintenance of bone and normal function of nerves and muscles. Phosphorus is an important constituent of adenosine triphosphate (ATP) and nucleic acid and is also essential for acid-base balance, bone and tooth formation. Red blood cells can not function properly without iron in haemoglobin, the oxygen-carrying pigment of red blood cells. Iron is also an important component of the cytochromes that function in cellular respiration. Magnesium, copper, selenium, zinc, iron, manganese and molybdenum are important co-factors found in the structure of certain enzymes and are indispensable in numerous biochemical pathways. Vertebrates need iodine to make thyroid hormones. Sodium, potassium and chlorine are important in the maintenance of osmotic balance between cells and the interstitial fluid. Magnesium is an important component of chlorophyll in plants. The interactions between nutrition and diseases, nutrition and drug metabolism have been reported. Excessive intake of some minerals can upset homeostatic balance and cause toxic side effects. For example, excess sodium intake is associated with high blood pressure and excess iron can cause liver damage. Also, severe shortages or self-prescribed minerals can alter the delicate balance in body functions that promotes health. The knowledge of the biochemistry of the mineral elements is also essential because individuals suffering from a chronic illness or taking medications that affect the body’s use of specific nutrients need to be enlightened. The aim of this paper is to review the biochemical functions and the importance of the mineral elements in health and disease conditions of humans, animals and plants as this will assist in the prevention of nutrition-related diseases and maintenance of good health for humans and animals that depend on plants for food. This paper could also serve as a ready source of literature review for researchers involved in nutritional sciences. Key words: Mineral elements, humans, animals, plants, nutrition.

843 citations

Journal ArticleDOI
TL;DR: Possible methods of limiting spread of infection from wildlife to cattle including the use of vaccines are outlined and the usefulness of DNA fingerprinting of M. bovis strains as an epidemiological tool and of BCG vaccination of humans and cattle as a control measure are reviewed.

806 citations

Patent
17 Sep 2004
TL;DR: In this paper, a system and methods for monitoring, diagnosing, and/or treating a patient are provided, where one or more individual medical procedures may be utilized to monitor, diagnose, and treat the patient.
Abstract: Systems and methods for monitoring, diagnosing, and/or treating a patient are provided. One or more individual medical procedures may be utilized to monitor, diagnose and/or treat the patient. Two or more of the individual medical procedures or may be used in combination to provide more comprehensive patient monitoring, diagnosis and/or therapy. One or more functions of two or more individual medical procedures may be used in combination to enhance patient monitoring, diagnosis and/or therapy. The medical procedures may be coordinated. Coordinated medical procedures may involve cooperative operation of two or more of the individual processes. Coordinated medical procedures may also involve cooperative operation of one or more functions of two or more of the individual processes.

663 citations