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2.
Vaccine ; 42(3): 535-540, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38199921

ABSTRACT

MVA-BN is an orthopoxvirus vaccine that provides protection against both smallpox and mpox. In June 2022, Canada launched a publicly-funded vaccination campaign to offer MVA-BN to at-risk populations including men who have sex with men (MSM) and sex workers. The safety of MVA-BN has not been assessed in this context. To address this, the Canadian National Vaccine Safety Network (CANVAS) conducted prospective safety surveillance during public health vaccination campaigns in Toronto, Ontario and in Vancouver, British Columbia. Vaccinated participants received a survey 7 and 30 days after each MVA-BN dose to elicit adverse health events. Unvaccinated individuals from a concurrent vaccine safety project evaluating COVID-19 vaccine safety were used as controls. Vaccinated and unvaccinated participants that reported a medically attended visit on their 7-day survey were interviewed. Vaccinated participants and unvaccinated controls were matched 1:1 based on age group, gender, sex and provincial study site. Overall, 1,173 vaccinated participants completed a 7-day survey, of whom 75 % (n = 878) also completed a 30-day survey. Mild to moderate injection site pain was reported by 60 % of vaccinated participants. Among vaccinated participants 8.4 % were HIV positive and when compared to HIV negative vaccinated individuals, local injection sites were less frequent in those with HIV (48 % vs 61 %, p = 0.021), but health events preventing work/school or requiring medical assessment were more frequent (7.1 % vs 3.1 %, p = 0.040). Health events interfering with work/school, or requiring medical assessment were less common in the vaccinated group than controls (3.3 % vs. 7.1 %, p < 0.010). No participants were hospitalized within 7 or 30 days of vaccination. No cases of severe neurological disease, skin disease, or myocarditis were identified. Our results demonstrate that the MVA-BN vaccine appears safe when used for mpox prevention, with a low frequency of severe adverse events and no hospitalizations observed.


Subject(s)
HIV Infections , Mpox (monkeypox) , Sexual and Gender Minorities , Smallpox Vaccine , Humans , Male , British Columbia , Homosexuality, Male , Immunization , Prospective Studies , Risk Factors , Smallpox Vaccine/adverse effects , Vaccination/adverse effects , Vaccines, Attenuated
3.
Exp Eye Res ; 98: 1-8, 2012 May.
Article in English | MEDLINE | ID: mdl-22465408

ABSTRACT

The purpose of this study was to test the hypothesis that mouse corneal stromal fibroblast and bone marrow-derived cell interactions augment corneal myofibroblast generation and, if so, to study whether such interactions are mediated by paracrine or juxtacrine mechanisms. Mouse bone marrow-derived cells and mouse corneal stromal fibroblasts were obtained from both mice with green fluorescent protein (GFP) expressed in all cells and normal GFP- BL6 control mice. To study the interactions of the different cell types, GFP+ cells of one type were co-cultured with GFP- cells of the other type in Primaria plates (to monitor juxtacrine signaling) or Transwell System plates (to monitor paracrine effects mediated by soluble mediators). Both cell types were cultured at a cell density of 1 × 10(5) cells per ml. The percentage of alpha smooth muscle actin+ myofibroblasts was significantly higher (ANOVA, p<0.001) when bone marrow-derived cells and mouse corneal stromal fibroblasts were co-cultured compared to when bone marrow-derived cells and mouse corneal stromal fibroblasts were cultured alone (control). The in vitro studies using GFP+ corneal fibroblasts or GFP+ bone marrow-derived cells demonstrated conclusively that both cells types could transform into myofibroblasts. However, the percentage of alpha smooth muscle actinassds+ myofibroblasts generated from either cell type precursor was higher when both cells were co-cultured together (juxtacrine) as compared to when bone marrow-derived cells and mouse corneal stromal fibroblasts were co-culture in different compartments of Transwell System (paracrine). Thus, more alpha smooth muscle actin+ GFP+ myofibroblasts were generated from GFP+ corneal stromal fibroblasts when GFP- bone marrow-derived cells were present and more alpha smooth muscle actin+ GFP+ myofibroblasts were generated from GFP+ bone marrow-derived cells when GFP- corneal stromal fibroblasts were present. Polyclonal anti-human latency associated peptide (LAP) (transforming growth factor-ß1) neutralizing antibody (a-LAP) and/or transforming growth factor-ß type I receptor kinase inhibitor (LY-364947) inhibited the generation of alpha smooth muscle actin+ myofibroblasts from either precursor cell in Transwell System co-culture experiments. These data suggest that TGFß is a paracrine modulator that regulates the generation of myofibroblasts from either corneal fibroblasts or bone marrow-derived cell precursors.


Subject(s)
Bone Marrow Cells/cytology , Cell Communication/physiology , Cell Transdifferentiation/physiology , Corneal Keratocytes/cytology , Corneal Stroma/cytology , Myofibroblasts/cytology , Actins/metabolism , Animals , Bone Marrow Cells/metabolism , Cell Separation , Cell Transdifferentiation/drug effects , Coculture Techniques , Corneal Keratocytes/metabolism , Enzyme Inhibitors/pharmacology , Female , Fluorescent Antibody Technique, Indirect , Gene Expression/genetics , Green Fluorescent Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Transgenic , Myofibroblasts/metabolism , Pyrazoles/pharmacology , Pyrroles/pharmacology , Signal Transduction , Transfection , Transforming Growth Factor beta1/metabolism
4.
Exp Eye Res ; 96(1): 65-9, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22251454

ABSTRACT

The purpose of this study was to investigate the role of interleukin-1 (IL-1) in modulating myofibroblast viability in mouse corneas with stromal opacity. Twenty-four female B6; 129S1-Il1r1tm1Roml/J homozygous IL-1RI knockout mice and 24 control B6129SF2/J mice were included in this study. Each mouse had opacity-generating irregular phototherapeutic keratectomy (PTK) performed with an excimer laser in one eye. Groups of 8 mice from each group were euthanized at one month, three months and six months after surgery and the eyes cryo-preserved. The contralateral eye served as unwounded control. Immunohistochemistry was performed for α-smooth muscle actin (SMA) in central sections of all corneas. The TUNEL assay for apoptosis was performed on 8 sections of four eyes from each group. No SMA+ cells were detected in the stroma of unwounded control or knockout corneas. SMA+ myofibroblast density was significantly higher (p < 0.001) in the IL-1RI knockout group than in the control group at one month, three and six months after irregular PTK. Mean TUNEL+ stromal cells in the anterior 50 µm of stroma was significantly lower in the IL-1RI knockout group compared to the control group at six months after irregular PTK (p = 0.04). These results corroborate the findings of recent in vitro work that demonstrated an antagonistic effect of TGFß and IL-1 on myofibroblast viability, and found that IL-1-triggered myofibroblast apoptosis was suppressed by TGFß. Thus, IL-1 is an important modulator of myofibroblast viability during corneal wound healing.


Subject(s)
Apoptosis , Corneal Opacity/pathology , Corneal Stroma/pathology , Disease Models, Animal , Myofibroblasts/pathology , Receptors, Interleukin-1/physiology , Actins/metabolism , Animals , Cell Survival , Corneal Stroma/metabolism , Female , Fluorescent Antibody Technique, Indirect , In Situ Nick-End Labeling , Mice , Mice, Inbred C57BL , Mice, Knockout , Myofibroblasts/metabolism , Photorefractive Keratectomy , Wound Healing
5.
Exp Eye Res ; 93(5): 786-9, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21933674

ABSTRACT

This study investigated whether PRM-151 (Promedior, Inc., Malvern, PA), a recombinant form of human pentraxin-2 (PTX-2, also referred to as serum amyloid P, hSAP), that inhibits differentiation of circulating monocytes into fibrocytes and profibrotic macrophages, could modulate generation of myofibroblasts after opacity-producing corneal injury in rabbits, and, therefore, have potential to reduce or prevent haze after PRK. Nine diopter PRK for myopia was performed with the VISX S4 IR laser. Four groups of 6 animals were treated in masked fashion: Group 1: 30 µl of topical PRM-151 (20 mg/ml) 6 times a day for 5 days; Group 2: 30 µl topical vehicle 6 times a day for 5 days; Group 3: 200 µl sub-conjunctival PRM-151 (total injection of 4 mg) immediately after surgery and every other day until day 8; Group 4: 200 µl sub-conjunctival injections of vehicle according to the same schedule as group 3. At one month after PRK, the animals were euthanized and immunohistochemistry was performed for the myofibroblast marker α-smooth muscle actin (SMA). The density of SMA+ cells/400× field in the central stroma was determined in each cornea. Myofibroblast density at one month after surgery was significantly lower (p = 0.006) after sub-conjunctival PRM-151 treatment (5.8 ± 2.8 cells/400× stromal field) compared to sub-conjunctival vehicle treatment (15.3 ± 2.9 cells/400× stromal field). There was no significant (p = 0.27) decrease in stromal myofibroblasts triggered by topical PRM-151 treatment (11.8 ± 6.6 cells/400× stromal field) compared to the topical vehicle treatment (14.2.8 ± 6.2 cells/400× stromal field). PRM-151 inhibits myofibroblast generation when administered by sub-conjunctival injection, but not when administered topically, after opacity-producing corneal injury. This study provides additional confirmation that bone marrow-derived cells contribute to corneal myofibroblast generation.


Subject(s)
Corneal Opacity/prevention & control , Corneal Stroma/drug effects , Homeodomain Proteins/administration & dosage , Monocytes/drug effects , Myofibroblasts/metabolism , Serum Amyloid P-Component/administration & dosage , Actins/metabolism , Animals , Cell Count , Cell Differentiation/drug effects , Corneal Injuries , Corneal Opacity/metabolism , Corneal Stroma/metabolism , Female , Fluorescent Antibody Technique, Indirect , Injections, Intraocular , Lasers, Excimer , Myopia/surgery , Photorefractive Keratectomy , Rabbits , Recombinant Proteins/administration & dosage
6.
Exp Eye Res ; 93(6): 810-7, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21978952

ABSTRACT

The purpose of this study was to investigate the role of transforming growth factor beta (TGFß) and/or platelet-derived growth factor-B (PDGF-B) blockade on the differentiation of vimentin and alpha-smooth muscle actin (αSMA)-expressing myofibroblasts associated with haze in mice. Mouse corneas had haze-generating irregular PTK (phototherapeutic keratectomy) and topical treatment with the vectors. Six study groups of PTK treated corneas, with four corneas per group in each experiment, were Group 1) treated with TGFß-KDEL vector interfering with TGFß signaling through anomalous sorting of cytokine bound to the expressed altered receptor; Group 2) treated with PDGF-B-KDEL vector interfering with PDGF signaling through anomalous sorting of cytokine bound to the expressed altered receptor; Group 3) treated with both TGFß-KDEL vector and PDGF-B-KDEL vector to interfere with signaling of both cytokines; Group 4) empty pGFPC1 vector; Group 5) empty pCMV vector; and Group 6) no vector treatment control. At one month after surgery, the corneas were analyzed by immunocytochemistry (IHC) for central stromal cells expressing myofibroblast markers vimentin and αSMA. The stroma of corneas treated with the TGFß-KDEL vector alone (p < 0.05) or both the TGFß-KDEL and PDGF-B-KDEL vectors (P < 0.05) had significantly lower density of vimentin-positive cells compared to the corresponding control group. The central stroma of corneas treated with the TGFß-KDEL vector (p < 0.05) or the PDGF-B-KDEL vector (p < 0.05) had lower density of αSMA-positive cells compared to the corresponding control group. The density of αSMA-positive stromal cells was also significantly lower (p < 0.05) when both the TGFß-KDEL and PDGF-B-KDEL and vectors were applied together compared to the corresponding control groups. This study provides in situ evidence that TGFß and PDGF-B have important roles in modulating myofibroblast generation in the mouse cornea after haze-associated injury.


Subject(s)
Cornea/metabolism , Corneal Opacity/prevention & control , Genetic Therapy/methods , Myofibroblasts/metabolism , Proto-Oncogene Proteins c-sis/metabolism , Transforming Growth Factor beta/metabolism , Actins/metabolism , Animals , Cells, Cultured , Cornea/pathology , Cornea/surgery , Corneal Opacity/etiology , Corneal Opacity/genetics , Corneal Opacity/metabolism , Corneal Opacity/pathology , Corneal Surgery, Laser , Disease Models, Animal , Down-Regulation , Female , Immunohistochemistry , Mice , Mice, Inbred C57BL , Myofibroblasts/pathology , Proto-Oncogene Proteins c-sis/genetics , Time Factors , Transfection , Transforming Growth Factor beta/genetics , Vimentin/metabolism
7.
Exp Eye Res ; 91(3): 456-61, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20603114

ABSTRACT

The purpose of this study was to determine whether myofibroblasts or other cells in the stroma in the cornea produce interleukin (IL)-1alpha or IL-1beta that could modulate myofibroblast viability in corneas with haze after photorefractive keratectomy (PRK). Twenty-four female rabbits had haze-generating PRK for 9 diopters of myopia and were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were removed, frozen in OCT at -80 degrees C, and analyzed by immunocytochemistry using primary antibodies to IL-1alpha, IL-1beta and alpha smooth muscle actin (SMA). Double immunostaining was performed for the co-localization of SMA with IL-1alpha or IL-1beta. Central dense haze and peripheral slight haze regions of each cornea were analyzed. SMA+ cells that expressed IL-1alpha protein were detected in both regions of the corneas at most time points following PRK. However, in the haze region at the 1, 3 and 4 week time points, significantly more (p<0.01) SMA+ cells did not express IL-1alpha. Also, in the haze region at all three time points, significantly more (p<0.01) SMA- cells than SMA+ cells expressed interleukin-1alpha protein. IL-1beta expression patterns in SMA+ and SMA- stromal cells was similar to that of IL-1alpha after PRK. Previous studies have demonstrated that IL-1alpha or IL-1beta triggers myofibroblast apoptosis in vitro, depending on the available concentration of apoptosis-suppressive TGFbeta. This study demonstrates that SMA- cells such as corneal fibroblasts, keratocytes, or inflammatory cells may produce IL-1alpha and/or IL-1beta that could act in paracrine fashion to regulate myofibroblast apoptosis--especially in the region where there is haze in the cornea after PRK was performed and SMA+ myofibroblasts are present at higher density. However, some SMA+ myofibroblasts themselves produce IL-1alpha and/or IL-1beta, suggesting that myofibroblast viability could also be regulated via autocrine mechanisms.


Subject(s)
Corneal Opacity/metabolism , Corneal Stroma/metabolism , Interleukin-1alpha/metabolism , Interleukin-1beta/metabolism , Photorefractive Keratectomy , Postoperative Complications , Actins/metabolism , Animals , Apoptosis , Cell Count , Corneal Opacity/etiology , Corneal Opacity/pathology , Corneal Stroma/pathology , Female , Fibroblasts/metabolism , Fibroblasts/pathology , Fluorescent Antibody Technique, Indirect , Myopia/surgery , Rabbits
8.
J Hosp Infect ; 70 Suppl 2: 11-4, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19022116

ABSTRACT

Most surgical site infections (SSIs) are caused by the patient's endogenous flora, and hence strategies to prevent bacterial contamination of the surgical incision have a central role in the prevention of such infections. However, even with optimal skin preparation, true sterilisation of the skin is not possible. A recently available method of preventing infection is a cyanoacrylate-based microbial sealant (marketed as InteguSeal(*) Microbial Sealant), which mechanically blocks migration of pathogens to the surgical wound. In in-vitro studies, this preoperative preparation reduced the recovery of pathogens commonly implicated in SSIs by up to 99.9%. Similarly, the incidence of wound contamination was lower with the microbial sealant than with antimicrobial surgical drapes in in-vivo studies. Other studies have shown that this microbial sealant significantly improves the effect of povidone iodine by fixing it on the skin and avoiding wash off, and does not affect normal skin transpiration. In a clinical study in 177 patients, the incidence of wound contamination was 53.0% with the sealant, compared with 68.7% using povidone iodine. The conclusion of this clinical study is that InteguSeal(*) Microbial Sealant significantly reduces surgical wound bacterial contamination when used in conjunction with 10% povidone iodine skin preparation, as compared to povidone iodine alone. The clinical experience to date is that this sealant is easy to apply and can be used with a variety of skin preparation solutions and with most wound closure techniques. It also has a good safety profile. This preparation may therefore form a valuable part of strategies to reduce bacterial contamination of surgical incisions, thereby potentially decreasing the risk of SSIs.


Subject(s)
Cyanoacrylates/therapeutic use , Skin/microbiology , Surgical Wound Infection/prevention & control , Animals , Anti-Infective Agents, Local/therapeutic use , Hernia, Inguinal/surgery , Humans , Povidone-Iodine/therapeutic use , Preoperative Care , Randomized Controlled Trials as Topic , Surgical Wound Infection/drug therapy , Surgical Wound Infection/microbiology , Swine
9.
J Electromyogr Kinesiol ; 18(5): 807-14, 2008 Oct.
Article in English | MEDLINE | ID: mdl-17449278

ABSTRACT

Spine motion has been described to have two regions, a neutral zone where lumbar rotation can occur with little resistance and an elastic zone where structures such as ligaments, facet joints and intervertebral disks resist rotation. In vivo, the passive musculature can contribute to further limiting the functional neutral range of lumbar motion. Movement out of this functional neutral range could potentially put greater loads on these structures. In this study, the range of lumbar curvature rotation was examined in twelve healthy, untrained volunteers at four torso inclination angles. The lumbar curvature during straight-leg lifting tasks was then defined as a percentage of this range of possible lumbar curvatures. Subjects were found to remain neutrally oriented during the flexion phase of a lifting task. During the extension phase of the lifting task, however, subjects were found to assume a more kyphotic posture, approaching the edge of the functional range of motion. This was found to be most pronounced for heavy lifting tasks. By allowing the lumbar curvature to go into a highly kyphotic posture, subjects may be taking advantage of stretch-shortening behavior in extensor musculature and associated tendons to reduce the energy required to raise the torso. Such a kyphotic posture during extension, however, may put excessive loading on the elastic structures of the spine and torso musculature increasing the risk of injury.


Subject(s)
Lifting , Lumbar Vertebrae/physiology , Movement/physiology , Pelvis/physiology , Postural Balance/physiology , Range of Motion, Articular/physiology , Task Performance and Analysis , Weight-Bearing/physiology , Adult , Female , Humans , Male
10.
J Vasc Access ; 8(4): 275-80, 2007.
Article in English | MEDLINE | ID: mdl-18161674

ABSTRACT

BACKGROUND: Although AV fistulas are the preferred access for hemodialysis and have low complication rates, failure to function remains high and time to first dialysis may be several months. METHODS: Data from a Computerized Patient Record System of patients undergoing AV fistula from October 2000 to March 2006 were reviewed for type of fistula, interval from AV fistula construction to first hemodialysis, patency period, and complication rate. RESULTS: 129 patients were identified who underwent 155 autogenous AV fistula constructions. The average age was 62.1 (range 40-84) years old. 114 radiocephalic and 41 brachiocephalic fistulas were performed. 57 (50%) radiocephalic fistulas allowed successful hemodialysis after an average length of 13+/-5 weeks with a primary patency of 13+/-4 months. 24 (42%) fistulas subsequently thrombosed, 7 (12%) developed fistula stenosis, and 2 (4%) developed steal syndrome. 28 (68%) brachiocephalic fistulas reached successful hemodialysis after 6+/-2 weeks with a primary patency of 16+/-7 months. Eleven (42%) of the brachiocephalic fistulas that reached hemodialysis remained patent while four (15%) thrombosed. Two (8%) brachiocephalic fistulas thrombosed before reaching hemodialysis. There were two incidences (5%) of steal syndrome in the brachiocephalic group with one case being severe leading to tissue loss in the hand. CONCLUSION: Brachiocephalic fistulas were superior to radiocephalic in both time to maturity, primary patency, and functional primary patency. Brachiocephalic fistulas had a higher maturation rate and were less likely to fail once hemodialysis began. Vascular surgeons should develop better patient selection to predict which fistulas will function successfully rather than risk complications of prolonged central catheters.


Subject(s)
Arteriovenous Shunt, Surgical/adverse effects , Brachial Artery/surgery , Brachiocephalic Veins/surgery , Graft Occlusion, Vascular/etiology , Radial Artery/surgery , Renal Dialysis , Vascular Patency , Adult , Aged , Aged, 80 and over , Brachial Artery/physiopathology , Brachiocephalic Veins/physiopathology , Female , Humans , Male , Middle Aged , Patient Selection , Radial Artery/physiopathology , Risk Assessment , Time Factors , Treatment Failure , Treatment Outcome , Veins
11.
Cancer Res ; 58(19): 4475-9, 1998 Oct 01.
Article in English | MEDLINE | ID: mdl-9766681

ABSTRACT

We have identified a novel human malignancy-associated gene (MAG) expressed in various malignant tumors including glioblastomas and hepatocellular carcinomas (HCCs) and in tumor preexisting conditions such as hepatitis C virus- and hepatitis B virus-induced liver cirrhosis. The expression of MAG was characterized using reverse transcription-PCR (RT-PCR), rapid amplification of cDNA ends PCR, RNA dot blotting, RNase protection assay, and Northern blot analysis. Rapid amplification of cDNA ends PCR yielded a 536-bp MAG fragment in HCC, macroregenerative liver nodules with dysplasia, and liver cirrhosis but not in normal liver or placenta. By RT-PCR, MAG expression was not found in 12 different normal tissues but found in 46 of 51 (90%) premalignant and malignant tissues of various sites. Embryonic liver and brain were positive for MAG expression together with tumors from the same organs, but the corresponding normal adult tissues were negative. By RNase protection assay, MAG mRNA was expressed in the HepG2 liver tumor cell line and in an ovarian carcinoma but not in normal liver. The estimated transcript size from Northern blot analysis was 8.8 kb. This novel gene may play a role in the progression of premalignant conditions and in the development of HCC and other cancers.


Subject(s)
Neoplasm Proteins/genetics , Neoplasms/genetics , Precancerous Conditions/genetics , Adult , Amino Acid Sequence , Base Sequence , Brain/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Embryo, Mammalian , Female , Glioblastoma/genetics , Glioblastoma/pathology , Hepatitis B/genetics , Hepatitis B/pathology , Hepatitis C/genetics , Hepatitis C/pathology , Humans , Liver/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Molecular Sequence Data , Neoplasm Proteins/chemistry , Neoplasms/pathology , Polymerase Chain Reaction , Precancerous Conditions/pathology , Pregnancy , Reference Values , Retrospective Studies , Risk Factors , Transcription, Genetic , Tumor Cells, Cultured
12.
Biochim Biophys Acta ; 1208(1): 45-54, 1994 Sep 21.
Article in English | MEDLINE | ID: mdl-8086438

ABSTRACT

The catalytic subunit of the major protein phosphatase associated with bovine cardiac myofibrils was purified to homogeneity. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of the enzyme revealed only one band with an apparent molecular weight of 37,000. On gel filtration chromatography, the phosphatase activity and the protein co-eluted as a single peak with an apparent molecular weight of 37,000. The purified enzyme was identified as the catalytic subunit of protein phosphatase 1, as determined by sensitivity to inhibitor 1, inhibitor 2, okadaic acid and by specific immunostaining. Evidence obtained with specific antipeptide antibodies demonstrated that this myofibril protein phosphatase was predominantly the alpha isoform of protein phosphatase 1. The purified catalytic subunit was completely inactive. It was activated by pretreatment with Co2+/trypsin in the presence of high ionic strength. Treatment with trypsin alone did not activate the latent enzyme. The enzyme was also activated by Co2+ or Mn2+ alone but not by Ca2+, Mg2+, Ni2+, Cu2+ or Zn2+. Activation of the enzyme was not reversed by removal of Co2+, but Mn(2+)-activated phosphatase activity was partially reversed when Mn2+ was removed. The catalytic subunit could form a 1:1 complex with inhibitor 2 in vitro. The resulting holoenzyme was also activated by pretreatment with Co2+. Since phosphatase 1 alpha is the major phosphatase associated with cardiac myofibril, it is suggested that it is responsible for the dephosphorylation of myosin and other myofibril phosphoproteins.


Subject(s)
Myocardium/enzymology , Myofibrils/enzymology , Phosphoprotein Phosphatases/metabolism , Amino Acid Sequence , Animals , Cations, Divalent , Cattle , Chromatography, Gel , Cobalt/pharmacology , Electrophoresis, Polyacrylamide Gel , Enzyme Activation/drug effects , Manganese/pharmacology , Molecular Sequence Data , Molecular Weight , Osmolar Concentration , Phosphoprotein Phosphatases/antagonists & inhibitors , Protein Phosphatase 1 , Proteins/metabolism , Trypsin/pharmacology
13.
Biochim Biophys Acta ; 872(1-2): 1-10, 1986 Jul 25.
Article in English | MEDLINE | ID: mdl-3015214

ABSTRACT

The predominant form of phosphorylase phosphatase activity in porcine renal cortical extracts was a polycation-stimulated protein phosphatase. This activity was present in extracts in a high-molecular-weight form which could be converted to a free catalytic subunit by treatment with ethanol, urea, or freezing and thawing in the presence of beta-mercaptoethanol. The catalytic subunit of the polycation-stimulated phosphatase was purified by chromatography on DEAE-Sephacel, heparin-Sepharose, and Sephadex G-75. The phosphatase appeared to be homogeneous on SDS-polyacrylamide gel electrophoresis. The enzyme had an apparent Mr of 35 000 on gel filtration and SDS-polyacrylamide gel electrophoresis. The purified phosphatase could be stimulated by histone H1, protamine, poly(D-lysine), poly(L-lysine) or polybrene utilizing phosphorylase a as the substrate. It preferentially dephosphorylated the alpha-subunit of phosphorylase kinase. The phosphatase was highly sensitive to inhibition by ATP. These results suggest that the renal polycation-stimulated phosphatase catalytic subunit is very similar to or identical with the skeletal muscle phosphatase form which has been previously designated phosphatase-2Ac.


Subject(s)
Kidney Cortex/enzymology , Phosphoprotein Phosphatases/isolation & purification , Adenosine Triphosphate/pharmacology , Animals , Chromatography, Gel , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Ethanol/pharmacology , Freezing , Hexadimethrine Bromide/pharmacology , Histones/pharmacology , Macromolecular Substances , Mercaptoethanol/pharmacology , Molecular Weight , Phosphorylation , Swine , Urea/pharmacology
14.
Biochim Biophys Acta ; 889(2): 200-7, 1986 Nov 28.
Article in English | MEDLINE | ID: mdl-3022826

ABSTRACT

The phosphorylase phosphatase activity of the holoenzyme form of phosphatase 2A isolated from extracts of porcine renal cortex or bovine heart was stimulated 600% and 500%, respectively, by the addition of histone H1. After conversion of the phosphatase to the catalytic subunit form by treatment with ethanol at room temperature, histone H1 stimulated activity by about 150% only. Purification of the catalytic subunit from porcine renal cortex yielded two forms of the enzyme which were separated by heparin-Sepharose chromatography. These forms were designated peak 1 and peak 2 according to their order of elution from the column. Peak 1 catalytic subunit was stimulated by more than 400% by histone H1, whereas peak 2 was stimulated by about 50% only. Based on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, peak 2 had a slightly higher Mr value than peak 1 (35,500 vs. 35,000). Incubation of the peak 2 phosphatase with trypsin converted it to a form that was similar to peak 1 with respect to Mr and stimulation by histone H1. When the catalytic subunit of phosphatase 2A was purified from bovine heart only one form was obtained. Bovine heart enzyme was similar to renal peak 2 in that it had an apparent Mr of 35,500 and was only slightly stimulated by histone H1. Treatment of the bovine heart catalytic subunit with trypsin, chymotrypsin or type 2 Ca2+-dependent proteinase decreased the apparent Mr by about 500 and increased histone H1 stimulation to about 500%. Thus, when a small peptide was removed by proteolysis, histone H1 stimulation of the 'nicked' catalytic subunit was similar to that obtained with the holoenzyme.


Subject(s)
Phosphoprotein Phosphatases/metabolism , Animals , Cattle , Chymotrypsin/metabolism , Electrophoresis, Polyacrylamide Gel , Ethanol/pharmacology , Histones/pharmacology , Kidney Cortex/enzymology , Kinetics , Macromolecular Substances , Molecular Weight , Myocardium/enzymology , Protein Phosphatase 2 , Swine , Trypsin/metabolism
15.
Biochim Biophys Acta ; 1011(2-3): 198-204, 1989 May 10.
Article in English | MEDLINE | ID: mdl-2540833

ABSTRACT

Several polycations were tested for their abilities to inhibit the activity of glycogen synthase kinase 3 (GSK-3). L-Polylysine was the most powerful inhibitor of GSK-3 with half-maximal inhibition of glycogen synthase phosphorylation occurring at approx. 100 nM. D-Polylysine and histone H1 were also inhibitory, but the concentration dependence was complex, and DL-polylysine was the least effective inhibitor. Spermine caused about 50% inhibition of GSK-3 at 0.7 mM and 70% inhibition at 4 mM. Inhibition of GSK-3 by L-polylysine could be blocked or reversed by heparin. A heat-stable polycation antagonist isolated from swine kidney cortex also blocked the inhibitory effect of L-polylysine on GSK-3 and blocked histone H1 stimulation of protein phosphatase 2A activity. Under the conditions tested, L-polylysine also inhibited GSK-3 catalyzed phosphorylation of type II regulatory subunit of cAMP-dependent protein kinase and a 63 kDa brain protein, but only slightly inhibited phosphorylation of inhibitor 2 or proteolytic fragments of glycogen synthase that contain site 3 (a + b + c). L-Polylysine at a concentration (200 nM) that caused nearly complete inhibition of GSK-3 stimulated casein kinase I and casein kinase II, but had virtually no effect on the catalytic subunit of cAMP-dependent protein kinase. These results suggest that polycations can be useful in controlling GSK-3 activity. Polycations have the potential to decrease the phosphorylation state of glycogen synthase at site 3, both by inhibiting GKS-3 as shown in this study and by stimulating the phosphatase reaction as shown previously (Pelech, S. and Cohen, P. (1985) Eur. J. Biochem. 148, 245-251).


Subject(s)
Glycogen Synthase/metabolism , Polyamines , Polymers/pharmacology , Protein Kinase Inhibitors , Calcium-Calmodulin-Dependent Protein Kinases , Glycogen Synthase Kinases , Phosphorylation , Polyelectrolytes , Polymers/antagonists & inhibitors
16.
Prog Retin Eye Res ; 18(3): 293-309, 1999 May.
Article in English | MEDLINE | ID: mdl-10192515

ABSTRACT

Stromal-epithelial interactions are key determinants of corneal function. Bi-directional communications occur in a highly coordinated manner between these corneal tissues during normal development, homeostasis, and wound healing. The best characterized stromal to epithelial interactions in the cornea are mediated by the classical paracrine mediators hepatocyte growth factor (HGF) and keratinocyte growth factor (KGF). HGF and KGF are produced by the keratocytes to regulate proliferation, motility, differentiation, and possibly other functions, of epithelial cells. Other cytokines produced by keratocytes may also contribute to these interactions. Epithelial to stromal interactions are mediated by cytokines, such as interleukin-1 (IL-1) and soluble Fas ligand, that are released by corneal epithelial cells in response to injury. Other, yet to be identified, cytokine systems may be released from the unwounded corneal epithelium to regulate keratocyte viability and function. IL-1 appears to be a master regulator of corneal wound healing that modulates functions such as matrix metalloproteinase production, HGF and KGF production, and apoptosis of keratocyte cells following injury. The Fas/Fas ligand system has been shown to contribute to the immune privileged status of the cornea. However, this cytokine-receptor system probably also modulates corneal cell apoptosis following infection by viruses such as herpes simplex and wounding. Pharmacologic control of stromal-epithelial interactions appears to offer the potential to regulate corneal wound healing and, possibly, treat corneal diseases in which these interactions have a central role.


Subject(s)
Corneal Stroma/physiology , Epithelium, Corneal/physiology , Fibroblast Growth Factors , Fas Ligand Protein , Fibroblast Growth Factor 10 , Fibroblast Growth Factor 7 , Growth Substances/physiology , Hepatocyte Growth Factor/physiology , Humans , Interleukin-1/physiology , Lacrimal Apparatus/metabolism , Membrane Glycoproteins/metabolism , Tears/metabolism , fas Receptor/metabolism
17.
Prog Retin Eye Res ; 20(5): 625-37, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11470453

ABSTRACT

The corneal wound healing cascade is complex and involves stromal-epithelial and stromal-epithelial-immune interactions mediated by cytokines. Interleukin-1 appears to be a master modulator of many of the events involved in this cascade. Keratocyte apoptosis is the earliest stromal event noted following epithelial injury and remains a likely target for modulation of the overall wound healing response. Other processes such as epithelial mitosis and migration, stromal cell necrosis, keratocyte proliferation, myofibroblast generation, collagen deposition, and inflammatory cell infiltration contribute to the wound healing cascade and are also likely modulated by cytokines derived from corneal cells, the lacrimal gland, and possibly immune cells. Many questions remain regarding the origin and fate of different cell types that contribute to stromal wound healing. Over a period of months to years the cornea returns to a state similar to that found in the unwounded normal cornea.


Subject(s)
Cornea/physiology , Corneal Stroma/cytology , Cytokines/physiology , Epithelium, Corneal/cytology , Wound Healing/physiology , Apoptosis , Cell Communication/physiology , Cell Division , Fibroblasts/cytology , Humans , Necrosis , Signal Transduction/physiology
18.
Arch Intern Med ; 160(10): 1425-30, 2000 May 22.
Article in English | MEDLINE | ID: mdl-10826454

ABSTRACT

BACKGROUND: We previously reported the prevalence and associations of abdominal aortic aneurysm (AAA) in 73451 veterans aged 50 to 79 years who underwent ultrasound screening. OBJECTIVE: To understand the prevalence of and principal positive and negative risk factors for AAA, and to assess reproducibility of our previous findings. METHODS: In the new cohort of veterans undergoing screening, 52 745 subjects aged 50 to 79 without history of AAA underwent successful ultrasound screening for AAA, after completing a questionnaire on demographics and potential risk factors. RESULTS: We detected AAA of 4.0 cm or larger in 613 participants (1.2%; compared with 1.4% in the earlier cohort). The direction and magnitude of the important associations reported in the first cohort were confirmed. Respective odds ratios for the major associations with AAA for the second and for the combined cohorts were as follows: 1.81 and 1.71 for age (per 7 years), 0.12 and 0. 18 for female sex, 0.59 and 0.53 for black race, 1.94 and 1.94 for family history of AAA, 4.45 and 5.07 for smoking, 0.50 and 0.52 for diabetes, and 1.60 and 1.66 for atherosclerotic diseases. The excess prevalence associated with smoking accounted for 75% of all AAAs of 4.0 cm or larger in the total population of 126 196. Associations for AAA of 3.0 to 3.9 cm were similar but tended to be somewhat weaker. CONCLUSIONS: Our findings confirm our previous cohort findings. Age, smoking, family history of AAA, and atherosclerotic diseases remained the principal positive associations with AAA, and female sex, diabetes, and black race remained the principal negative associations.


Subject(s)
Aortic Aneurysm, Abdominal/epidemiology , Mass Screening , Veterans/statistics & numerical data , Aged , Aortic Aneurysm, Abdominal/etiology , Aortic Aneurysm, Abdominal/surgery , Cohort Studies , Cross-Sectional Studies , Female , Humans , Incidence , Male , Middle Aged , Risk Factors , Ultrasonography
19.
Arch Intern Med ; 160(8): 1117-21, 2000 Apr 24.
Article in English | MEDLINE | ID: mdl-10789604

ABSTRACT

BACKGROUND: Little is known about the rate at which new abdominal aortic aneurysms (AAAs) develop or whether screening older men for AAA, if undertaken, should be limited to once in a lifetime or repeated at intervals. METHODS: A large population of veterans, aged 50 through 79 years, completed a questionnaire and underwent ultrasound screening for AAA. Of these, 5151 without AAA on the initial ultrasound (defined as infrarenal aortic diameter of 3.0 cm or larger) were selected randomly to be invited for a second ultrasound screening after an interval of 4 years. Local records and national databases were searched to identify deaths and AAA diagnoses made during the study interval in subjects who did not attend the rescreening. RESULTS: Of the 5151 subjects selected for a second screening, 598 (11.6%) had died (none due to AAA), and 20 (0.4%) had an interim diagnosis of AAA. A second screening was performed on 2622 (50.9%), of whom 58 (2.2%; 95% confidence interval, 1.6%-2.8%) had new AAA. Three new AAAs were 4.0 to 4.9 cm, 10 were 3.5 to 3.9 cm, and 45 were 3.0 to 3.4 cm. Independent predictors of new AAA at the second screening included current smoker (odds ratio, 3.09; 95% confidence, 1.74-5.50), coronary artery disease (odds ratio, 1.81; 95% confidence interval, 1.07-3.07), and, in a separate model using a composite variable, any atherosclerosis (odds ratio, 1.97; 95% confidence interval, 1.16-3.35). Adding the interim and rescreening diagnosis rates suggests a 4-year incidence rate of 2.6%. Rescreening only in subjects with infrarenal aortic diameter of 2.5 cm or greater on the initial ultrasound would have missed more than two thirds of the new AAAs. CONCLUSIONS: A second screening is of little practical value after 4 years, mainly because the AAAs detected are small. However, the incidence that we observed suggests that a second screening after longer intervals (ie, more than 8 years) may provide yields similar to those seen in initial screening and therefore warrants further study.


Subject(s)
Aortic Aneurysm, Abdominal/diagnostic imaging , Aged , Confidence Intervals , Coronary Disease/diagnostic imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Odds Ratio , Ultrasonography
20.
Minerva Chir ; 60(5): 327-38, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16210983

ABSTRACT

Minimally invasive esophagectomy is emerging as an alternative option to open esophagectomy for benign and malignant esophageal diseases. This article provides a detailed review of the history of minimally invasive esophagectomy and an update on the currently accepted techniques for minimally invasive esophagectomy and its outcomes.


Subject(s)
Esophagectomy/methods , Laparoscopy , Humans , Laparoscopy/methods , Thoracoscopy/methods
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