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1.
Hand Clin ; 37(4): 537-543, 2021 11.
Article in English | MEDLINE | ID: mdl-34602133

ABSTRACT

Lunotriquetral (LT) ligament injuries are uncommon, however, should be considered in patients with ulnar-sided wrist pain. LT injuries are often associated with other injuries but can occur in isolation. Understanding the anatomy and pathomechanics will aid in making the diagnosis. Similar to other injuries, a thorough history and focused physical examination is critical. Radiographs may show normal findings; however, advanced imaging can support the diagnosis. Arthroscopy remains the gold standard for diagnosis. Most patients do well with conservative management; however, injury acuity and severity will direct surgical management. Anatomy, pathophysiology, and treatment options are discussed.


Subject(s)
Wrist Injuries , Arthroscopy , Humans , Ligaments, Articular/surgery , Radiography , Wrist Injuries/diagnosis , Wrist Injuries/surgery , Wrist Joint
2.
Nat Biotechnol ; 38(5): 563-572, 2020 05.
Article in English | MEDLINE | ID: mdl-32341561

ABSTRACT

Recombinant protein therapeutics, vaccines, and plasma products have a long record of safety. However, the use of cell culture to produce recombinant proteins is still susceptible to contamination with viruses. These contaminations cost millions of dollars to recover from, can lead to patients not receiving therapies, and are very rare, which makes learning from past events difficult. A consortium of biotech companies, together with the Massachusetts Institute of Technology, has convened to collect data on these events. This industry-wide study provides insights into the most common viral contaminants, the source of those contaminants, the cell lines affected, corrective actions, as well as the impact of such events. These results have implications for the safe and effective production of not just current products, but also emerging cell and gene therapies which have shown much therapeutic promise.


Subject(s)
Biological Products/standards , Data Collection/methods , Drug Contamination/prevention & control , Viruses/isolation & purification , Cell Culture Techniques , Drug Industry , Humans , Information Dissemination , Massachusetts
3.
Physiol Rep ; 2(4): e12002, 2014.
Article in English | MEDLINE | ID: mdl-24771696

ABSTRACT

Abstract Many epithelial cells form polarized monolayers under in vivo and in vitro conditions. Typically, epithelial cells are cultured for differentiation on insert systems where cells are plated on a porous filter membrane. Although the cultured monolayers have been a standard system to study epithelial physiology, there are some limits: The epithelial cells growing inside the commercial inserts are not optimal to visualize directly through lenses on inverted microscopes. The cell images are optically distorted and background fluorescence is bright due to the filter membrane positioned between the cells and the lens. In addition, the cells are not easily accessible by electrodes due to the presence of tall side walls. Here, we present the design, fabrication, and practical applications of an improved system for analysis of polarized epithelial monolayers. This new system allows (1) direct imaging of cells without an interfering filter membrane, (2) electrophysiological measurements, and (3) detection of apical secretion with minimal dilution. Therefore, our culture method is optimized to study differentiated epithelial cells at the single-cell and subcellular levels, and can be extended to other cell types with minor modifications.

4.
Biotechniques ; 55(1): 34-7, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23834383

ABSTRACT

Here we present a convenient method for easy hand selection of enzymatically isolated small tissues such as islets of Langerhans. Islets are continuously collected in a micropipette tip connected to a peristaltic pump. After entering the conical micropipette tip, the islets are quickly dragged up by solution flow, but this movement subsequently decreases as the flow rate decreases. Thus, the islets are trapped at a specific height where downward gravitation balances upward buoyancy and the drag provided by solution flow. Our device allows more efficient isolation of islets compared to conventional manual collection methods.


Subject(s)
Cell Separation/instrumentation , Cell Separation/methods , Islets of Langerhans/cytology , Animals , Humans , Insulin/metabolism , Islets of Langerhans/metabolism , Mice , Pancreas/cytology
5.
Proc Natl Acad Sci U S A ; 109(51): E3539-48, 2012 Dec 18.
Article in English | MEDLINE | ID: mdl-23184982

ABSTRACT

Secretory granules (SGs) sequester significant calcium. Understanding roles for this calcium and potential mechanisms of release is hampered by the difficulty of measuring SG calcium directly in living cells. We adapted the Förster resonance energy transfer-based D1-endoplasmic reticulum (ER) probe to develop a unique probe (D1-SG) to measure calcium and pH in secretory granules. It significantly localizes to SGs and reports resting free Ca(2+) of 69 ± 15 µM and a pH of 5.8. Application of extracellular ATP to activate P2Y receptors resulted in a slow monotonic decrease in SG Ca(2+) temporally correlated with the occurrence of store-operated calcium entry (SOCE). Further investigation revealed a unique receptor-mediated mechanism of calcium release from SGs that involves SG store-operated Orai channels activated by their regulator stromal interaction molecule 1 (STIM1) on the ER. SG Ca(2+) release is completely antagonized by a SOCE antagonist, by switching to Ca(2+)-free medium, and by overexpression of a dominant-negative Orai1(E106A). Overexpression of the CRAC activation domain (CAD) of STIM1 resulted in a decrease of resting SG Ca(2+) by ∼75% and completely abolished the ATP-mediated release of Ca(2+) from SGs. Overexpression of a dominant-negative CAD construct(CAD-A376K) induced no significant changes in SG Ca(2+). Colocalization analysis suggests that, like the plasma membrane, SG membranes also possess Orai1 channels and that during SG Ca(2+) release, colocalization between SGs and STIM1 increases. We propose Orai channel opening on SG membranes as a potential mode of calcium release from SGs that may serve to raise local cytoplasmic calcium concentrations and aid in refilling intracellular calcium stores of the ER and exocytosis.


Subject(s)
Calcium Channels/physiology , Calcium/metabolism , Membrane Proteins/physiology , Neoplasm Proteins/physiology , Secretory Vesicles/metabolism , Calcium/chemistry , Calcium Signaling/physiology , Cell Line, Tumor , Cell Membrane/metabolism , Cytoplasm/metabolism , Endoplasmic Reticulum/metabolism , Exocytosis , Humans , Hydrogen-Ion Concentration , Models, Biological , ORAI1 Protein , Photochemistry/methods , Stromal Interaction Molecule 1
6.
PDA J Pharm Sci Technol ; 65(6): 580-8, 2011.
Article in English | MEDLINE | ID: mdl-22294580

ABSTRACT

CONFERENCE PROCEEDING Proceedings of the PDA/FDA Adventitious Viruses in Biologics: Detection and Mitigation Strategies Workshop in Bethesda, MD, USA; December 1-3, 2010 Guest Editors: Arifa Khan (Bethesda, MD), Patricia Hughes (Bethesda, MD) and Michael Wiebe (San Francisco, CA) The production of biologic drugs using mammalian cell production systems offers the benefits of high yield, proper protein folding, and faithful post-translational modifications. However, mammalian cell culture is vulnerable to contamination with adventitious agents, including mouse minute virus (MMV). The case study presented here demonstrates that MMV is a ubiquitous threat to CHO (Chinese hamster ovary) cell-based production of biologic drugs and that animal-free media components can be a contamination source. Compounding the risk posed by MMV, the contamination may be "silent," with no impact on cell viability and product titers. Furthermore, contamination may not be detected using in vitro virus assays, and assays based on PCR (polymerase chain reaction) are required for reliable detection. The development of effective corrective and preventative action (CAPA) was greatly aided by the identification of the source of the contamination as an animal-free recombinant media additive. The execution of a CAPA that included disposal of contaminated materials, decontamination of the facility, and replacement of the contaminated raw material allowed the resumption of MMV-free production.


Subject(s)
CHO Cells , Cricetulus , Animals , Biological Products , Cell Culture Techniques , Culture Media , Drug Contamination , Embryo, Mammalian/chemistry , Equipment Contamination , Humans , Mice , Minute Virus of Mice , Protein Folding , Viruses
7.
Am J Respir Cell Mol Biol ; 42(1): 105-12, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19346319

ABSTRACT

Progressive lung damage in cystic fibrosis (CF) has been linked to inadequate airway mucosal hydration. We previously demonstrated that an inositol tetrakisphosphate analog, 1-O-octyl-2-O-butyryl-myo-inositol 3,4,5,6-tetrakisphosphate octakis(propionoxymethyl)ester (INO-4995), regulates airway secretory and absorptive processes, affecting mucosal hydration by prolonged (24 h) inhibition of Na(+) and fluid absorption in CF human nasal epithelia (CFHNE). The objectives of this study were to further assess clinical potential of INO-4995 in CF through ascertaining in vivo activity in mice with CF, determining the effects of repeated administration on potency and determining cytoplasmic half-life. Uptake and metabolism of [(3)H]INO-4995 was monitored with HPLC to calculate intracellular half-life. INO-4995 was administered in vitro repeatedly over 4 to 8 days to CFHNE. Fluid absorption was assessed by blue dextran exclusion, and basal short-circuit current was measured in Ussing chambers. INO-4995 (1-100 microg/kg) was dosed intranasally either as a single dose or once per day over 4 days to gut-corrected CF mice. [(3)H]INO-4995 was rapidly taken up by epithelial cultures and converted to the active drug, which had a half-life of 40 hours. Repeated daily application of INO-4995 to CFHNE lowered the effective concentration for inhibition of fluid absorption and amiloride-sensitive short-circuit current in cultured CFHNE, and reduced nasal potential difference to nearly control levels in gut-corrected CF mice. Ca(2+)-activated Cl(-) channel activity was also boosted in cultures. Mouse nasal levels fell from abnormal levels to within 2 muA of normal with repeated exposure to 0.8 microg/kg over 4 days. These data support further development of INO-4995 for the treatment of CF.


Subject(s)
Epithelial Cells/drug effects , Epithelium/drug effects , Inositol Phosphates/pharmacology , Inositol Phosphates/pharmacokinetics , Animals , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Epithelial Cells/cytology , Female , HeLa Cells , Homozygote , Humans , Mice , Mice, Inbred CFTR , Mice, Knockout , Time Factors
8.
J Allergy Clin Immunol ; 116(3): 586-93, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16159628

ABSTRACT

BACKGROUND: Exercise-induced bronchoconstriction (EIB) is a common cause of symptoms in a subgroup of asthmatic subjects. The pathobiology that makes this group of asthmatic subjects susceptible to bronchoconstriction after a brief period of exercise remains poorly understood. OBJECTIVE: We sought to determine whether there are differences in lower airway inflammation and production of cytokines and eicosanoids between asthmatic subjects with and without EIB. METHODS: Two distinct groups of asthmatic subjects based on a priori definitions were identified, one with moderate-to-severe EIB and the other without significant bronchoconstriction after exercise challenge. Both groups met the definition of asthma on the basis of bronchodilator response, bronchial hyperresponsiveness, or both. A comparative immunopathology study was conducted by using induced sputum to identify differences in lower airway inflammation and production of cytokines and eicosanoids. RESULTS: The groups had similar baseline lung function and bronchodilator response and did not have any asthma exacerbations within the prior year. The concentration of columnar epithelial cells was markedly higher in the group with EIB (1.4 x 10(5) vs 2.9 x 10(4) cells/mL, P=.01). The concentration of eosinophils was higher in the group with EIB (3.6 x 10(4) vs 4.9 x 10(3) cells/mL P=.04). Cysteinyl leukotrienes (CysLTs; 727.7 vs 151.9 pg/mL, P=.01) and the ratio of CysLTs to prostaglandin E(2) (1.85 vs 1.04, P=.002) in the airways were higher in the group with EIB. CONCLUSION: Injury to the airway epithelium, overexpression of CysLTs, relative under production of prostaglandin E(2), and greater airway eosinophilia are distinctive immunopathologic features of asthma with EIB.


Subject(s)
Asthma, Exercise-Induced/immunology , Asthma, Exercise-Induced/pathology , Lung/immunology , Lung/pathology , Adult , Cytokines/analysis , Cytokines/immunology , Eicosanoids/analysis , Eicosanoids/immunology , Eosinophils/immunology , Female , Humans , Male , Middle Aged , Sputum/chemistry , Sputum/cytology , Sputum/immunology
9.
Am J Respir Crit Care Med ; 172(6): 679-86, 2005 Sep 15.
Article in English | MEDLINE | ID: mdl-15947280

ABSTRACT

RATIONALE: Exercise-induced bronchoconstriction (EIB) is a highly prevalent condition with unclear pathogenesis. Two competing theories of the pathogenesis of EIB differ regarding the inflammatory basis of this condition. OBJECTIVES: Our goals were to establish whether epithelial cell and mast cell activation with release of inflammatory mediators occurs during EIB and how histamine and cysteinyl leukotriene antagonists alter the airway events occurring during EIB. METHODS: Induced sputum was used to measure mast cell mediators and eicosanoids at baseline and 30 minutes after exercise challenge in 25 individuals with asthma with EIB. In a randomized, double-blind crossover study, the cysteinyl leukotriene antagonist montelukast and antihistamine loratadine or two matched placebos were administered for two doses before exercise challenge. MAIN RESULTS: The percentage of columnar epithelial cells in induced sputum at baseline was associated with the severity of EIB. After exercise challenge, histamine, tryptase, and cysteinyl leukotrienes significantly increased and prostaglandin E(2) and thromboxane B(2) significantly decreased in the airways, and there was an increase in columnar epithelial cells in the airways. The concentration of columnar epithelial cells was associated with the levels of histamine and cysteinyl leukotrienes in the airways. Treatment with montelukast and loratadine inhibited the release of cysteinyl leukotrienes and histamine into the airways, but did not inhibit the release of columnar epithelial cells into the airways. CONCLUSIONS: These data indicate that epithelial cells, mast cell mediators, and eicosanoids are released into the airways during EIB, supporting an inflammatory basis for EIB.


Subject(s)
Asthma/complications , Asthma/metabolism , Bronchitis/etiology , Bronchitis/physiopathology , Bronchoconstriction , Exercise , Inflammation Mediators/metabolism , Acetates/therapeutic use , Adolescent , Adult , Asthma/drug therapy , Asthma/physiopathology , Cross-Over Studies , Cyclopropanes , Double-Blind Method , Female , Forced Expiratory Volume , Histamine H1 Antagonists, Non-Sedating/therapeutic use , Humans , Leukotriene Antagonists/therapeutic use , Loratadine/therapeutic use , Lung/physiopathology , Male , Middle Aged , Quinolines/therapeutic use , Severity of Illness Index , Sulfides
10.
Am J Physiol Cell Physiol ; 289(3): C512-20, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15857902

ABSTRACT

Amiloride-sensitive, epithelial Na(+) channel (ENaC)-mediated, active absorption of Na(+) is elevated in the airway epithelium of cystic fibrosis (CF) patients, resulting in excess fluid removal from the airway lumen. This excess fluid/volume absorption corresponds to CF transmembrane regulator-linked defects in ENaC regulation, resulting in the reduced mucociliary clearance found in CF airways. Herein we show that INO-4995, a synthetic analog of the intracellular signaling molecule, D-myo-inositol 3,4,5,6-tetrakisphosphate, inhibits Na(+) and fluid absorption across CF airway epithelia, thus alleviating this critical pathology. This conclusion was based on electrophysiological studies, fluid absorption, and (22)Na(+) flux measurements in CF airway epithelia, contrasted with normal epithelia, and on electrophysiological studies in Madin-Darby canine kidney cells and 3T3 cells overexpressing ENaC. The effects of INO-4995 were long-lasting, dose-dependent, and more pronounced in epithelia from CF patients vs. controls. These findings support preclinical development of INO-4995 for CF treatment and demonstrate for the first time the therapeutic potential of inositol polyphosphate derivatives.


Subject(s)
Cystic Fibrosis/drug therapy , Inositol Phosphates/pharmacology , Nasal Mucosa/metabolism , Prodrugs/pharmacology , Sodium/metabolism , 3T3 Cells , Animals , Body Fluids/metabolism , Cells, Cultured , Cystic Fibrosis/metabolism , Dogs , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Humans , Inositol Phosphates/chemistry , Kidney/cytology , Membrane Potentials/drug effects , Mice , Nasal Mucosa/cytology , Patch-Clamp Techniques , Prodrugs/chemistry
11.
Protein Expr Purif ; 38(2): 177-83, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15555933

ABSTRACT

Alpha-Fetoprotein (AFP) is a 68 kDa glycoprotein expressed at high levels by the fetal liver and yolk with transcription repressed to very low levels after birth. Transfer of fetal AFP through the placenta into the circulation of the mother is correlated with remission of rheumatoid arthritis, multiple sclerosis, and other autoimmune disorders. AFP is therefore under development as a biopharmaceutical for the treatment of autoimmune diseases. The clinical evaluation of AFP requires the production of hundreds of grams of highly purified and biologically active protein. We have produced goats that express a form of the human AFP transgene under the control of the beta-casein promoter. In this form of rhAFP, the single N-linked glycosylation site was removed by mutagenesis (N233Q). Here, we describe a purification protocol for this recombinant human (rh)AFP from the milk of these transgenic goats. A three-column procedure was developed to produce gram quantities of highly purified rhAFP. Near- and far-UV circular dichroism spectra of human umbilical cord blood AFP and rhAFP were essentially identical, suggesting that the structure is not affected by removal of the glycosylation site. Furthermore, the cell binding and pharmacokinetics of purified rhAFP were similar to human AFP isolated from cord blood. Our results demonstrate that an active form of rhAFP can be produced on industrial scale by expression in transgenic goat milk.


Subject(s)
Goats , Milk/chemistry , Recombinant Fusion Proteins/isolation & purification , alpha-Fetoproteins/isolation & purification , Animals , Animals, Genetically Modified , Female , Fetal Blood/chemistry , Goats/genetics , Humans , Male , Mice , Mice, Inbred Strains , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/pharmacokinetics , Transgenes , U937 Cells , alpha-Fetoproteins/metabolism , alpha-Fetoproteins/pharmacokinetics
12.
Vet Immunol Immunopathol ; 91(3-4): 205-15, 2003 Feb 10.
Article in English | MEDLINE | ID: mdl-12586483

ABSTRACT

Dendritic cells (DC) are potent inducers of acquired immunity due to their ability to present antigens in the context of a costimulatory environment and consequently serve an essential role in vaccine efficacy. Strategies to enhance their function, such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4 treatment to induce DC differentiation from peripheral blood monocytes, may therefore be useful as vaccine adjuvants. We now have evaluated the effect of recombinant GM-CSF on the differentiation of DC in swine. GM-CSF mRNA was readily detected in porcine splenocytes, with increased levels following treatment of the cells with ConA and LPS. Porcine GM-CSF was cloned and expressed in the methylotrophic yeast, Pichia pastoris, as a glycosylated protein that induced proliferation of porcine bone marrow cells. P. pastoris-derived GM-CSF induced expression of antigen presenting (MHC class II) and costimulatory (CD80-CD86) molecules and enhanced antigen presenting cell (APC) function consistent with the induction of functional DC. Thus, recombinant GM-CSF produced by P. pastoris may be a potent adjuvant for swine vaccines.


Subject(s)
Cell Differentiation/drug effects , Dendritic Cells/cytology , Dendritic Cells/drug effects , Granulocyte Colony-Stimulating Factor/pharmacology , Pichia/genetics , Swine/immunology , Animals , Antigen Presentation/drug effects , Antigens, Surface/analysis , Antigens, Surface/metabolism , Bone Marrow Cells/cytology , Bone Marrow Cells/drug effects , Cell Division/drug effects , Dendritic Cells/immunology , Dose-Response Relationship, Immunologic , Gene Expression , Granulocyte Colony-Stimulating Factor/genetics , Granulocyte Colony-Stimulating Factor/metabolism , Immunophenotyping , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins
13.
Am J Physiol Gastrointest Liver Physiol ; 283(5): G1042-50, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12381517

ABSTRACT

Pancreatic duct epithelial cells (PDEC) mediate the secretion of fluid and electrolytes and are exposed to refluxed bile. In nontransformed cultured dog PDEC, which express many ion transport pathways of PDEC, 1 mM taurodeoxycholic acid (TDCA) stimulated an (125)I(-) efflux inhibited by DIDS and 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) and a (86)Rb(+) efflux inhibited by charybdotoxin. Inhibition by 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA)-AM suggests mediation via increased intracellular Ca(2+) concentration, whereas the absence of lactate dehydrogenase release excludes cellular toxicity. At 1 mM, TDCA stimulated a larger (125)I(-) efflux than glycodeoxycholate; two dihydroxy bile acids, taurochenodeoxycholate and TDCA, were similarly effective, whereas a trihydroxy bile acid, taurocholate, was ineffective. In Ussing chambers, 1 mM serosal or 2 mM luminal TDCA stimulated an I(sc) increase from confluent PDEC monolayers. TDCA also stimulated 1) a short-circuit current (I(sc)) increase from basolaterally permeabilized PDEC subject to a serosal-to-luminal Cl(-) gradient that was inhibited by BAPTA-AM, DIDS, and NPPB and 2) an I(sc) increase from apically permeabilized PDEC subject to a luminal-to-serosal K(+) gradient inhibited by BAPTA-AM and charybdotoxin. Along with the efflux studies, these findings suggest that TDCA interacts directly with PDEC to stimulate Ca(2+)-activated apical Cl(-) channels and basolateral K(+) channels. Monolayer transepithelial resistance was only minimally affected by 1 mM serosal and 2 mM luminal TDCA but decreased after exposure to higher TDCA concentrations (2 mM serosal and 4 mM luminal). A secretory role for bile acids should be considered in pancreatic diseases associated with bile reflux.


Subject(s)
Cholagogues and Choleretics/pharmacology , Pancreatic Ducts/drug effects , Pancreatic Ducts/physiology , Taurodeoxycholic Acid/pharmacology , Animals , Cells, Cultured , Dogs , Electric Impedance , Epithelial Cells/cytology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Iodides/metabolism , L-Lactate Dehydrogenase/metabolism , Pancreatic Ducts/cytology , Pancreatic Ducts/metabolism , Rubidium Radioisotopes/pharmacokinetics
14.
J Healthc Inf Manag ; 16(3): 47-51, 2002.
Article in English | MEDLINE | ID: mdl-12119846

ABSTRACT

HIPAA may finally force healthcare organizations to make long-postponed decisions to increase the use of automation and technology for report distribution. For most, the direct benefits will far outweigh the costs.


Subject(s)
Access to Information/legislation & jurisprudence , Health Insurance Portability and Accountability Act , Management Information Systems/legislation & jurisprudence , Computer Security , Confidentiality , Documentation , Electronic Data Processing , Medical Records Systems, Computerized/legislation & jurisprudence , United States
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