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1.
Bone Rep ; 12: 100282, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32478145

ABSTRACT

Patients with rheumatoid arthritis (RA) have very different outcomes, particularly with regard to bone erosions. Since osteoclasts are responsible for bone destruction adjacent to rheumatoid synovium, profiling osteoclasts from circulating precursors in RA could help identify patients at risk for bone destruction. In this study, we sought to determine whether the functional characteristics of osteoclasts generated from their blood precursors were modified by RA activity or were intrinsic to osteoclasts and associated with the RA phenotype (erosive or not). Osteoclasts were generated in vitro from peripheral blood mononuclear cells (PBMCs) of subjects with RA (n = 140), as well as sex- and age-matched healthy controls (n = 101). Osteoclastic parameters were analyzed at baseline and during the follow-up for up to 4 years, with regular assessment of RA activity, bone erosions, and bone mineral density (BMD). As a validation cohort, we examined RA patients from the Early Undifferentiated PolyArthritis (EUPA) study (n = 163). The proportion of CD14+ PBMC was higher in RA than in control subjects, but inversely correlated with the 28-joint disease activity score (DAS28). Also surprisingly, in osteoclast cultures from PBMCs, active RA was associated with lower osteoclastogenic capacity, while in vitro bone resorption per osteoclast and resistance to apoptosis were similar in both active and quiescent RA. In a small subgroup analysis, osteoclasts from subjects with recent RA that had progressed at four years to an erosive RA exhibited at baseline greater resistance to apoptosis than those from patients remaining non-erosive. Our findings establish that when RA is active, circulating monocytes have a reduced potential to generate osteoclasts from PBMCs in vitro. In addition, osteoclasts associated with erosive disease had resistance to apoptosis from the start of RA.

2.
Bone ; 48(3): 588-96, 2011 Mar 01.
Article in English | MEDLINE | ID: mdl-20959150

ABSTRACT

Increases in local and systemic bone resorption are hallmarks of rheumatoid arthritis (RA). Osteoclasts are implicated in these processes and their enhanced differentiation may contribute to bone destruction. We observed that in vitro osteoclastogenesis varies among healthy individuals and hypothesized that increased osteoclastogenesis could be a marker for the presence of RA. Our objective in the present study was to determine if in vitro osteoclastogenesis from peripheral blood mononuclear cells (PBMCs) was different in patients with RA compared to healthy controls and osteoarthritis (OA) patients. Expression of CD14 in PBMCs was quantified and PBMCs were incubated for 21 days in the presence of the osteoclastogenic cytokines M-CSF and RANKL. Differentiation on cortical bone slices permitted the analysis of bone resorption while apoptotic potential was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. In vitro osteoclastogenesis was higher in PBMCs from RA patients compared to controls, and a similar increase was observed in the percentage of osteoclast precursors in RA patients. Osteoclasts from RA patients showed lower apoptotic rates than osteoclasts from healthy controls. No difference was observed in bone resorption activity between RA patients and controls. Interestingly, the difference in osteoclast number and apoptosis rate allowed the implementation of an algorithm capable of distinguishing patients with RA from controls. In conclusion, our study shows that osteoclast differentiation from PBMCs is enhanced in patients with RA, and this difference can be explained by both a higher percentage of osteoclast precursors in the blood and by the reduced apoptotic potential of mature osteoclasts.


Subject(s)
Apoptosis , Arthritis, Rheumatoid/pathology , Cell Differentiation , Osteoclasts/pathology , Osteogenesis , Stem Cells/pathology , Adult , Aged , Biomarkers/metabolism , Case-Control Studies , Cell Movement , Cohort Studies , Demography , Female , Humans , Male , Middle Aged , Models, Biological , Multivariate Analysis , Osteoarthritis/pathology , Prospective Studies
3.
J Med Genet ; 40(12): 865-71, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14684682

ABSTRACT

BACKGROUND: Mutations of the transforming growth factor beta (TGFbeta) receptor components ENDOGLIN and ALK-1 cause the autosomal dominant vascular disorder hereditary haemorrhagic telangiectasia (HHT). Heterozygous mutations of the type II receptor BMPR2 underlie familial primary pulmonary hypertension. OBJECTIVE: To investigate kindreds presenting with both pulmonary hypertension and HHT. METHODS: Probands and families were identified by specialist pulmonary hypertension centres in five countries. DNA sequence analysis of ALK-1, ENDOGLIN, and BMPR2 was undertaken. Cellular localisation was investigated by heterologous overexpression of mutant constructs in both BAEC and HeLa cells. The impact of a novel sequence variant was assessed through comparative analysis and computer modelling. RESULTS: Molecular analysis of 11 probands identified eight missense mutations of ALK-1, one of which was observed in two families. Mutations were located within exons 5 to 10 of the ALK-1 gene. The majority of ALK-1 mutant constructs appeared to be retained within the cell cytoplasm, in the endoplasmic reticulum. A novel GS domain mutation, when overexpressed, reached the cell surface but is predicted to disrupt conformational changes owing to loss of a critical hydrogen bond. Two novel missense mutations were identified in ENDOGLIN. CONCLUSIONS: The association of pulmonary arterial hypertension and HHT identifies an important disease complication and appears most common among subjects with defects in ALK-1 receptor signalling. Future studies should focus on detailed molecular analysis of the common cellular pathways disrupted by mutations of ALK-1 and BMPR2 that cause inherited pulmonary vascular disease.


Subject(s)
Activin Receptors, Type I/genetics , Hypertension, Pulmonary/genetics , Telangiectasia, Hereditary Hemorrhagic/complications , Activin Receptors, Type I/analysis , Activin Receptors, Type I/chemistry , Activin Receptors, Type II , Adolescent , Adult , Aged , Amino Acid Sequence , Antigens, CD , Bone Morphogenetic Protein Receptors, Type II , DNA Mutational Analysis , Endoglin , Endoplasmic Reticulum/chemistry , Female , Genetic Predisposition to Disease , Humans , Hypertension, Pulmonary/diagnosis , Male , Middle Aged , Models, Molecular , Mutation, Missense , Protein Serine-Threonine Kinases/genetics , Receptors, Cell Surface , Structural Homology, Protein , Telangiectasia, Hereditary Hemorrhagic/diagnosis , Telangiectasia, Hereditary Hemorrhagic/genetics , Vascular Cell Adhesion Molecule-1/genetics
4.
Neoplasia ; 3(5): 385-94, 2001.
Article in English | MEDLINE | ID: mdl-11687949

ABSTRACT

Increasing evidence suggests that activated erk regulates cell functions, at least in part, by mechanisms that do not require gene transcription. Here we show that the map kinase, erk, decorates microtubules (MTs) and mitotic spindles in both parental and mutant active ras-transfected 10T1/2 fibroblasts and MCF10A breast epithelial cells. Approximately 20% of total cellular erk decorated MTs in both cell lines. A greater proportion of activated erk was associated with MTs in the presence of mutant active H-ras than in parental cells. Activation of erk by the ras pathway coincided with a decrease in the stability of MT, as detected by a stability marker. The MKK1 inhibitor, PD98059 and transfection of a dominant negative MKK1 blocked ras-induced instability of MTs but did not modify the association of erk with MTs or affect MT stability of the parental cells. These results indicate that the subset of active erk kinase that associates with MTs contributes to their instability in the presence of a mutant active ras. The MT-associated subset of active erk likely contributes to the enhanced invasive and proliferative abilities of cells containing mutant active H-ras.


Subject(s)
Genes, ras/physiology , Microtubules/metabolism , Mitogen-Activated Protein Kinases/metabolism , Acetylation , Blotting, Western , Cell Line, Transformed , Female , Fibroblasts/metabolism , Flavonoids/pharmacology , Fluorescent Antibody Technique, Indirect , Humans , MAP Kinase Kinase 1 , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/antagonists & inhibitors , Tubulin/metabolism , Tumor Cells, Cultured/metabolism
5.
New Phytol ; 151(3): 671-682, 2001 Sep.
Article in English | MEDLINE | ID: mdl-33853265

ABSTRACT

• The question 'are fragmented wild populations of raspberry adaptively differentiated from each other and from cultivated forms of the same species?' is addressed here. • Plants collected from the coast, where commercial raspberries are grown, northwards by 49 km to an altitude of 600 m in Tayside, Scotland, were cultured in two common environments. Twenty phenotypic traits were recorded over 2 yr, on vegetative primocanes and then the single dominant floricane retained for year 2. A novel approach is presented for selecting traits that best discriminate between individuals using principal coordinate analysis. Phenotypic variation among accessions was then quantified using principal coordinate analysis followed by principal component analysis. • A consistent north-south trend was found. Plants from northern sites were shorter, bushier with less lateral growth and fewer flowers per lateral on the dominant fruiting cane. Plants from southern sites produced few, tall primocanes with greater cane diameters, lateral growth and flowering. The results were consistent across test environments. • The results confirm substantial, adaptive differentiation between populations and suggest a limited effect of cultivation on wild forms.

6.
Can J Anaesth ; 47(8): 830-1, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10958108
8.
Cell Motil Cytoskeleton ; 36(4): 355-62, 1997.
Article in English | MEDLINE | ID: mdl-9096957

ABSTRACT

The telotrophic ovariole of Rhodnius prolixus is richly endowed with microtubules (MTs). An extensive, stable array of MTs packs the trophic core and trophic cords which link the nurse cell compartments to the growing oocytes. This system is excellent to study MT-based transport as the MTs are believed to play a role in transport of nurse cell-produced mitochondria, ribosomes, and mRNAs to the oocytes. We investigated MT polarity and molecular MT motors in this unidirectional transport system. Hook decoration revealed that the MTs of the trophic core and cords have their plus (+) ends in the tropharium and minus (-) ends in the oocytes. Video differential interference optics (DIC) microscopy showed that vesicle transport was saltatory, ATP-dependent, and had an average velocity of 0.77 micron/sec toward the oocyte. Transport was sensitive to 2 mM N-ethylmaleimide (NEM) and 50 microM vanadate and resistant to 1 mM 5'-adenylylimidodiphosphate (AMP-PNP) and 5 microM vanadate. We report that the unipolar, acetylated trophic cord MTs play a direct role in nurse cell-oocyte transport via a cytoplasmic dynein-like retrograde motor.


Subject(s)
Microtubules/physiology , Microtubules/ultrastructure , Oocytes/physiology , Ovary/cytology , Ovary/physiology , Adenosine Triphosphate/pharmacology , Adenylyl Imidodiphosphate/pharmacology , Animals , Cell Movement , Chemotaxis/drug effects , Dyneins/physiology , Female , Kinesins/physiology , Kinetics , Microscopy, Electron , Rhodnius
9.
Crit Care Med ; 22(1): 171-6, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8124961

ABSTRACT

OBJECTIVES: To assess the outcome of children who required endotracheal intubation after bone marrow transplantation and to determine whether prognostic indicators that might assist decision-making regarding the institution of mechanical ventilation could be identified. DESIGN: Retrospective chart review. SETTING: Critical care, reverse isolation unit at a university hospital. PATIENTS: Fifty-four pediatric bone marrow transplant recipients who required endotracheal intubation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The following variables were assessed for effect on survival: a) the presence of additional nonhematoporetic organ system failure; b) the duration of required ventilatory assistance; c) the etiology of respiratory failure; d) the presence of significant graft vs. host disease; and e) the underlying disease for which the transplant was done. Six of 54 intubated pediatric bone marrow transplant recipients were extubated and discharged from the hospital. No patient with a diagnosis of leukemia or with multiple organ system failure could be extubated or discharged from the hospital. The presence of pulmonary parenchymal disease indicated poor prognosis for survival. CONCLUSIONS: The decision to intubate a pediatric bone marrow transplant patient remains a difficult one. In this population, multiple organ system failure and primary pulmonary parenchymal disease were associated with a high mortality rate. These factors should be taken into account before and throughout the course of mechanical ventilation in this patient population.


Subject(s)
Bone Marrow Transplantation , Critical Care/methods , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Intubation, Intratracheal , Lung Diseases/mortality , Lung Diseases/therapy , Male , Multiple Organ Failure/mortality , Prognosis , Respiration, Artificial , Retrospective Studies , Treatment Outcome
10.
J Nematol ; 25(2): 181-8, 1993 Jun.
Article in English | MEDLINE | ID: mdl-19279756

ABSTRACT

To isolate potential insect biocontrol agents, entomogenous nematodes were surveyed in Tennessee plant nurseries in 1991. Soil samples from 113 nursery sites were baited with greater wax moth (Galleria mellonella) larvae, house cricket (Acheta domesticus) adults, lesser mealworm (Alphitobius diaperings) adults, and house fly (Musca domestica) larvae. Heterorhabditis bacteriophora and Steinernema carpocapsae were each recovered from 17 soil samples. Heterorhabditis bacteriophora was more common in habitats with crape myrtle (Lagerstroemia indica) and Chinese juniper (Juniperus chinensis) than other nursery plants, and S. carpocapsae was more frequently recovered from habitats with juniper and Southern magnolia (Magnolia grandiflora). Bulk density, electrical conductivity, organic matter, pH, temperature, and moisture content of the entomogenous-nematode positive soil samples were compared. Other nematode genera recovered with insect baits included Rhabditis sp., Pelodera sp., Cryptaphelenchoides sp., and Mesodiplogaster sp., which was recovered from a greater percentage of soil samples than the other five genera.

11.
Surgery ; 111(4): 462-5, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1557692

ABSTRACT

Early hepatic artery thrombosis after orthotopic liver transplantation results in massive injury to hepatocytes and the bile duct epithelium. In the fulminate form, impaired liver synthetic function is expressed by encephalopathy and coagulopathy. Ischemic bile duct injury is associated with the disruption of the biliary anastomosis, bile duct strictures, and intrahepatic bilomas. The inability of the liver macrophages to clear translocated portal blood intestinal pathogens results in persistent bacteremia and sepsis. The major radiologic finding is the radiographic evidence of gas gangrene of the liver graft. Early recognition and correct interpretation of the radiologic findings, immediate removal of the liver graft, and placement of the patient on venous-venous bypass or total hepatic devascularization while a new liver is being procured and retransplantation are the only hope for survival.


Subject(s)
Gas Gangrene/etiology , Hepatic Artery , Liver Transplantation , Postoperative Complications/diagnosis , Thrombosis/diagnosis , Adult , Child, Preschool , Gas Gangrene/diagnostic imaging , Humans , Liver Transplantation/pathology , Male , Middle Aged , Necrosis , Postoperative Complications/diagnostic imaging , Thrombosis/complications , Thrombosis/diagnostic imaging , Tomography, X-Ray Computed
12.
J Ark Med Soc ; 86(4): 156-8, 1989 Sep.
Article in English | MEDLINE | ID: mdl-2529246

ABSTRACT

In a multicenter study of 30 patients treated with ciprofloxacin (mean daily dosage, 1000 mg per day; mean duration of treatment, 10.6 days) for a variety of infections, 14 were microbiologically proven. Of these, bacteriologic cure and/or improvement resulted in 92.3% of cases. For all 30 infections clinical cure and/or improvement resulted in 88.9% of cases. A total of ten infections were classified as chronic. Overall there were 5/30 (16%) adverse reactions (ADRs), however, only two were definitely related to ciprofloxacin therapy. For three ADRs the relationship to therapy was uncertain. Therapy with ciprofloxacin was discontinued in one (3.3%) patient because of adverse effects. Four patients elected to continue ciprofloxacin therapy despite mild side effects.


Subject(s)
Bacterial Infections/drug therapy , Ciprofloxacin/therapeutic use , Adult , Aged , Female , Humans , Male , Middle Aged , Multicenter Studies as Topic
13.
Brain Res ; 371(1): 166-70, 1986 Apr 16.
Article in English | MEDLINE | ID: mdl-3486693

ABSTRACT

Alert cats were rotated sinusoidally (0.25 Hz) in their sagittal plane while viewing optokinetic motion in their horizontal plane. Vertical and horizontal vestibulo-ocular reflex (VOR) was measured in the dark before and after 2 h of these adaptation stimuli in upright or onside orientation of the cat. Onside exposure produced maximal adaptive horizontal VOR at the training frequency. Upright exposure produced highest gain at lower frequencies. A cat with inoperative vertical canals adapted only to upright exposure. We conclude that in the presence of horizontal image rotation either vertical canal or otolith stimulation can produce adaptation in VOR direction and stimulation of both produces complex adaptation dynamics.


Subject(s)
Eye Movements , Reflex/physiology , Vestibule, Labyrinth/physiology , Adaptation, Physiological , Animals , Biophysical Phenomena , Biophysics , Cats , Electrooculography , Neuronal Plasticity , Otolithic Membrane/physiology , Rotation , Semicircular Canals/physiology
14.
Brain Res ; 371(1): 162-5, 1986 Apr 16.
Article in English | MEDLINE | ID: mdl-3486692

ABSTRACT

Horizontal and vertical vestibulo-ocular reflex (VOR) eye movements were recorded in alert cats before and after adaptation to vertical optokinetic motion coupled with horizontal rotation at 0.05, 0.25 or 1.0 Hz. Within 15-30 min, the VOR measured in darkness acquired a vertical component; the maximal directional change in the VOR occurred at the frequency of the adapting stimulus. At other frequencies the gain was less and there were phase leads or lags for higher or lower frequencies, respectively. Adaptive VOR was stable for at least 14 h in unrestrained animals with no visual input and decayed within 30 min during rotation in a stationary visual world.


Subject(s)
Eye Movements , Reflex/physiology , Vestibule, Labyrinth/physiology , Adaptation, Physiological , Animals , Biophysical Phenomena , Biophysics , Cats , Electrooculography , Neuronal Plasticity , Rotation
15.
Article in English | MEDLINE | ID: mdl-2877775

ABSTRACT

The incorporation of [14C]leucine into protein was measured in liver preparations and blood of rats following the s.c. administration of methylmercury hydroxide (24 mg/kg body wt) or turpentine (5.0 ml/kg body wt). The translatability of the RNA obtained from polysomes in an mRNA-dependent reticulocyte lysate was elevated significantly in the preparations derived from the treated rats compared to control rats. Immunoprecipitation of the labelled translation products or of serum proteins showed that the mRNA activity and the synthesis of alpha 1-acid glycoprotein, an acute phase reactant, was elevated by the methylmercury treatment as well as by the turpentine-induced inflammatory response.


Subject(s)
Methylmercury Compounds/toxicity , Orosomucoid/biosynthesis , Animals , In Vitro Techniques , Liver/drug effects , Liver/metabolism , Male , Molecular Weight , Polyribosomes/metabolism , RNA, Messenger/metabolism , Rats , Rats, Inbred Strains , Reticulocytes/metabolism
16.
Can Anaesth Soc J ; 28(3): 288-9, 1981 May.
Article in English | MEDLINE | ID: mdl-7237226

ABSTRACT

A new device which can be used as an oral airway or as an aid for blind oral intubation of the trachea is described. A case report describing the use of the device during intubation of a patient in the prone position is presented.


Subject(s)
Intubation, Intratracheal/instrumentation , Adult , Humans , Male , Posture
18.
Head Neck Surg ; 1(5): 392-408, 1979.
Article in English | MEDLINE | ID: mdl-162508

ABSTRACT

This is the concluding portion of a two-part series dealing with the effects and manifestations in the oral cavity of radiation therapy of head and neck tumors. Preradiation and postradiation extractions in dentulous patients, as well as dental maintenance of such patients (including fluoride treatments follow-up, and restorative care), are discussed. Guidelines for the dental management of edentulous patients are also presented at length (this section covers risk of bone necrosis, soft liners, timing of denture placement, dentures and preexisting bone necrosis, soft-tissue necrosis and dentures, morbidity, and prosthodontic procedures). The article concludes with a brief discussion of osteoradionecrosis and soft-tissue necrosis.


Subject(s)
Dental Care for Disabled , Head and Neck Neoplasms/radiotherapy , Mandibular Diseases/therapy , Mouth Neoplasms/radiotherapy , Osteoradionecrosis/prevention & control , Osteoradionecrosis/therapy , Radiation Injuries/prevention & control , Radiation Injuries/therapy , Dental Caries/prevention & control , Denture, Complete/adverse effects , Fluorides, Topical/therapeutic use , Humans , Hyperbaric Oxygenation , Mandibular Diseases/prevention & control , Mouth, Edentulous/rehabilitation , Necrosis/etiology , Tooth Extraction
19.
Head Neck Surg ; 1(4): 301-12, 1979.
Article in English | MEDLINE | ID: mdl-500366

ABSTRACT

This is the first article in a two-part series dealing with the effects and manifestations in the oral cavity of radiation therapy of head and neck tumors. In this section, oral mucous membranes, taste buds, edema and trismus, diet, salivary glands, bone, periodontium, teeth, and composition of oral flora are discussed. Dental management of the dentulous patient is then approached; criteria for preradiation extraction are delineated. In the next issue of Head & Neck Surgery, the final article in this series will discuss preradiation and postradiation extractions and will elaborate on the dental management (fluoride treatments, follow-up, and restorative care) of the dentulous patient. Dental management of the edentulous patient will also be presented.


Subject(s)
Head and Neck Neoplasms/radiotherapy , Mouth Diseases/etiology , Mouth/radiation effects , Radiation Injuries/etiology , Bacteria/cytology , Humans , Jaw/radiation effects , Mouth/microbiology , Mouth Mucosa/radiation effects , Oral Hygiene , Periodontium/radiation effects , Radiotherapy Dosage , Salivary Glands/radiation effects , Taste Buds/radiation effects , Tooth/radiation effects , Tooth Extraction , Trismus/etiology
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