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R Altman

Publications and source records attributed to R Altman.

At least 19 recordsLinked to original sources
PubMed2006

MRI and non-cartilaginous structures in knee osteoarthritis.

Magnetic resonance imaging (MRI) provides a sensitive tool for examining all the structures involved in the osteoarthritis (OA) process. While much of the MRI literature previously focussed on cartilage, there is increasing research on whole-organ evaluation and including features such as synovitis, bone marrow edema, and meniscal and ligamentous pathology. The aim of this session at the Outcome Measures in Rheumatology Clinical Trials (OMERACT)-Osteoarthritis Research Society International (OARSI) Workshop for Consensus in Osteoarthritis Imaging was to describe the current MRI methods for identifying and quantifying non-cartilaginous structures and review their associations with both OA symptoms and structural progression. Although there is much experience in measuring synovitis (derived from the rheumatoid arthritis literature), only one study has reported an association of MRI-detected synovitis and effusions with OA pain. Bone marrow edema lesions, which may represent areas of trabecular remodelling, have been associated with pain and compartment-specific structural deterioration. MRI studies have confirmed the frequency and importance of meniscal damage in progressive cartilage loss, but not related such damage to symptoms. Osteophytes have been associated with cartilage loss and malalignment to the side of the osteophyte. Ligament damage, including anterior cruciate ligament tears, has been found more commonly than expected in painful OA knees. Improvements in quantitative and semi-quantitative assessments of non-cartilage features will greatly assist understanding of the OA process and its response to therapy.

Bone Marrow↗
PubMed2006

Recombinant factor VIIa reverses the inhibitory effect of aspirin or aspirin plus clopidogrel on in vitro thrombin generation.

BACKGROUND: Antiplatelet drugs constitute the therapy of choice for acute coronary syndromes, but bleeding can be a side-effect requiring treatment. Restoration of normal platelet activity is also mandatory before urgent surgery. This study investigated: (a) whether a regimen of aspirin or clopidogrel plus aspirin significantly inhibited platelet thrombin generation (TG); and (b) the reversal of this inhibition by recombinant activated factor VII (rFVIIa). METHODS AND RESULTS: TG was evaluated by the lag time, time to peak, peak of TG, and area under the curve after 35 min of assay (AUC(0 --> 35 min)). These measures were examined by the calibrated automated thrombography method in 22 healthy volunteers, 22 volunteers after a 100 mg day(-1) aspirin intake (200 mg first day) for 5-7 days, and 22 healthy volunteers after aspirin 100 mg day(-1) (200 mg first day) plus clopidogrel 75 mg day(-1) (300 mg first day) for 4-7 days. The TG parameters were measured under basal conditions and after platelet stimulation by sodium arachidonate (AA), adenosine 5'-diphosphate (ADP), collagen and rFVIIa in normal non-aspirinated as well as in vivo aspirinated platelet-rich plasma (PRP) or aspirin plus clopidogrel PRP. Lag time was shorter (P < 0.05), and peak of TG and AUC(0 --> 35 min) were significantly greater (P < 0.01 for both), in PRP activated with ADP, collagen, AA or FVIIa than in non-activated PRP from normal subjects. Both non-activated PRP and activated PRP prepared from platelets obtained from volunteers after aspirin intake showed significant prolongation of the time parameters but there was less effect on peak of TG and AUC(0 --> 35 min). For most parameters, aspirin plus clopidogrel administration showed to be more effective compared with the effect obtained by aspirin alone. When rFVIIa was added to ASA-PRP or ASA + Clop PRP, lag time (P < 0.001 for all) and time to peak (P < 0.001-0.017) were significantly shortened, indicating that rFVIIa reverses the inhibitory effect of these anti-aggregating agents. CONCLUSION: Platelets activated by AA, ADP, collagen or FVIIa triggered TG. This effect was inhibited by aspirin plus clopidogrel, suggesting an additional benefit of this drug combination for preventing thrombosis. rFVIIa reverses the inhibitory effect of aspirin or aspirin plus clopidogrel, and could be useful for bleeding complications or when acute surgery is needed during treatment with these antiplatelet drugs.

Adult↗
PubMed2000

Abciximab treatment in vitro after aspirin treatment in vivo has additive effects on platelet aggregation, ATP release, and P-selectin expression.

To prevent arterial thrombosis, abciximab is administered together with aspirin. However, whether or not there are benefits to combine abciximab with aspirin is not yet well defined. Healthy volunteers were studied for the effect of aspirin + abciximab using sodium arachidonate and adenosine diphosphate (ADP) alone or in combination to induce platelet activation/aggregation. Abciximab produced complete inhibition of platelet aggregation induced with ADP but only 40% inhibition of aggregation induced by 0.75-mmol/l sodium arachidonate. Abciximab added in vitro to platelet-rich plasma (PRP) from platelets from aspirin-treated donors produced an almost complete inhibition of platelet aggregation. Aspirin, and abciximab alone, did not inhibit adenosine triphosphate (ATP) release as thoroughly as aspirin + abciximab did. Abciximab (3-5 microg/ml) produced inhibition of P-selectin expression induced with 5 (from 46.2 +/- 6.0% to 27.4 +/- 7.0%, P=0.002) and 20-micromol/l ADP (from 53.1 +/- 8.1% to 35.1 +/- 11.0%, P=0.019), but no effect was observed when 0.75-mmol/l sodium arachidonate was used (P=0.721). Aspirin diminished P-selectin expression in sodium arachidonate-stimulated platelets (from 77.7 +/- 11.8% to 40.2 +/- 3.6%, P<0.0001) in non-aspirinated and platelets from aspirin-treated donors, respectively. Abciximab (3, 4, and 5 microg/ml) added to platelets from aspirin-treated donors decreased P-selectin expression in platelets stimulated with sodium arachidonate from 40.2 +/- 8.6% to 25.6 +/- 11.5% (P=0.027), to 20.5 +/- 3.5% (P<0.0001), and to 22.5 +/- 1.8% (P<0.0001). We concluded that the antiplatelet effect of abciximab is greatly increased by aspirin.

Abciximab↗
PubMed2000

Effect of atorvastatin on hemorheologic-hemostatic parameters and serum fibrinogen levels in hyperlipidemic patients.

Plasma fibrinogen and hemorheologic-hemostatic factors contribute to dyslipidemia-induced morbidity. Some of these parameters can be favorably affected when abnormal serum lipoprotein levels are corrected. Thus, we investigated whether treatment with atorvastatin would result in changes in plasma viscosity and other hemorheologic and hemostatic parameters. Twenty-two hyperlipidemic men at a university lipid clinic were treated single-blinded with atorvastatin 80 mg/day for 12 weeks to determine hemostatic-hemorheologic parameters including blood viscosity, fibrinogen levels, whole blood platelet aggregation, tissue plasminogen activator antigen, hematocrit, plasminogen activator inhibitor activity, factor VII activity, red blood cell (RBC) deformity and lipid ratio, sedimentation rate, and fasting serum lipoprotein levels. Atorvastatin treatment provided significant lowering of serum lipoprotein levels: low-density lipoprotein -53% (p = 0.0001), very low density lipoprotein -43% (p = 0.0001), and triglycerides -35% (p < 0.0001). These effects were accompanied by changes in plasma viscosity -10% (p = 0.0007), arachidonic acid-induced whole blood platelet aggregation -11% (p = 0.006), factor VII -8% (p = 0.001), RBC lipid composition +5% (p = 0.0003), and RBC sedimentation -33% (p = 0.0002). Plasma fibrinogen levels were not affected. Thus, atorvastatin 80 mg/day produced marked reductions in serum low-density lipoprotein cholesterol (-53%), very low density lipoprotein cholesterol (-43%), and triglycerides levels (-35%), and significant changes in plasma viscosity as well as other hemorheologic-hemostatic parameters, but no changes in plasma fibrinogen levels.

Adult↗
PubMed2000

Fast platelet suppression by lysine acetylsalicylate in chronic stable coronary patients. Potential clinical impact over regular aspirin for coronary syndromes.

BACKGROUND: The rapid utilization of fibrinolytics following Q-wave myocardial infarction has clearly modified the evolution of this disease. However, it is still not known whether the immediate inhibition of platelet aggregation (PA) during the coronary event improves outcomes. HYPOTHESIS: The present study was designed to test, in patients with known coronary artery disease (chronic stable angina), whether the particular kinetic pattern of lysine acetylsalicylate (LA) compared with aspirin may affect the time to onset of inhibition of platelet aggregation. METHODS: Ten patients suffering from chronic stable angina participated in this study to compare the efficacy and speed of the inhibition of PA with 320 mg of LA versus 320 mg of aspirin. All patients discontinued the use of aspirin and any other anti-inflammatory agents for 15 days prior to the beginning of the study. They were randomly assigned to LA or aspirin. Blood specimens were obtained to measure the PA at admission, and 5, 10, 20, 30, and 60 min after ingestion. Patients continued to take the assigned drug once a day for the following 4 days. On Day 5, a new blood sample was taken. After this, patients underwent a 15-day wash-out period, and then crossed over to the opposite drug. The samples were analyzed immediately using platelet-rich plasma stimulated with adenosine diphosphate (ADP) 2 mumol/l, collagen 1 microgram/ml, epinephrine 20 mumol/l, and sodium arachidonate acid 0.75 mm/l. RESULTS: The same level of PA inhibition after 30 and 60 min of aspirin administration can be obtained with LA 5 min following ingestion (sodium arachidonate acid: LA: 16.3 +/- 25.9 vs. aspirin 57.6 +/- 8.2; p = 0.00014; collagen: LA 18.9 +/- 20.1 vs. aspirin 47.2 +/- 10.5; p = 0.00092; ADP: LA 27.3 +/- 18.4 vs. aspirin 39.7 +/- 21.8, p = 0.18; epinephrine: LA 22.0 +/- 9.9 vs. aspirin 55.4 +/- 10.9, p = 0.00002. CONCLUSIONS: Platelet aggregation inhibition immediately following LA may have significant clinical implications for the treatment of coronary syndromes.

Analysis of Variance↗
PubMed2000

Effect of sodium arachidonate on thrombin generation through platelet activation--inhibitory effect of aspirin.

BACKGROUND: Sodium arachidonate was used in this study to determine its capacity to generate thrombin through platelet activation. Whether aspirin prevent this effect was also investigated. METHODS AND RESULTS: Seventeen healthy volunteers without and after 160 mg/day aspirin intake for 3-5 days were studied. Lag-time and TG at basal condition and after platelet stimulation by sodium arachidonate (AA) were measured in normal non-aspirinated as well as "in vivo" aspirinated platelet rich plasma. (PRP). The lag-time was statistically significant shorter in non-aspirinated PRP activated with AA compared with non-activated PRP. This effect was inhibited by aspirin. In non-aspirinated PRP, there was an increase of TG at 4 and 6 min. incubation when platelets were activated with AA but the difference disappeared after 8 min. incubation, (84 +/- 71; 148 +/- 58 and 142 +/- 92 nmol/L respectively) compared with non-aspirinated. non-activated platelets (16 +/- 23; 55 +/- 56 and 111 +/- 76 nmol/L at 4,6 and 8 min, p < 0.0001, p < 0.0001 and p = 0.292, respectively). The AUCo-->22 min were 520.6 +/- 545.5 in non-aspirinated, non-stimulated PRP and 808.9 +/- 617, in non-aspirinated PRP activated with sodium arachidonate (p = 0.014). Aspirin administered in vivo produced a decrease of TG in PRP activated with AA. CONCLUSION: Platelet activated by AA trigged TG. This effect was inhibited by aspirin and could be an additional beneficial effect of aspirin in the prevention of thrombosis.

Adult↗
PubMed1999

Lack of association between prior infection with Chlamydia pneumoniae and acute or chronic coronary artery disease.

BACKGROUND: Higher than normal serologic titers and the detection of bacteria within atheroma have suggested an association between Chlamydia pneumoniae (C. pneumoniae) infection and coronary heart disease (CHD), but the relationship has not been well established. HYPOTHESIS: The study was designed to establish a lack of relationship between chronic C. pneumoniae infection and CHD. METHODS: Chlamydia-specific IgG-antibody was assayed using an indirect immunofluorescence test in the serum of 159 patients with severe arterial disease and 203 patients with a heart valve prostheses and no demonstrable CHD. Fatal and nonfatal vascular events and systemic thromboembolism were recorded over a 2-year period. RESULTS: In the arterial group 107 patients (67.3%) and in the valvular group 120/203 (59.1%) were positive for C. pneumoniae antibody. The number of patients with fatal or nonfatal vascular events (double end point) in the arterial and valvular groups was 23 and 2, respectively (p < .0001). Triple end points (fatal plus nonfatal vascular events plus thromboembolism) were also more frequent in the arterial group (p < 0.002). The prevalence of chlamydia antibody positivity was the same in the arterial and valvular groups, and the occurrence of clinical events was also the same for chlamydia-positive (227 patients) as for chlamydia-negative (135 patients). After adjustment for confounding variables, only arterial disease was a predictive factor for double (OR 17.0; 95% CI 3.94-73.3) or triple (OR 3.12; 95% CI 1.56-6.25) end points. CONCLUSION: We find C. pneumoniae chronic infection not to be an independent risk factor for acute or chronic arterial disease.

Acute Disease↗
PubMed1999

Effects of ticlopidine or ticlopidine plus aspirin on platelet aggregation and ATP release in normal volunteers: why aspirin improves ticlopidine antiplatelet activity.

Aspirin and ticlopidine are used to prevent arterial thrombosis. In some clinical settings ticlopidine is administered with aspirin for improving antithrombotic effect. We administered aspirin (100 mg/day), ticlopidine (500 mg/day), or ticlopidine and aspirin for 7 days to healthy volunteers. Platelet aggregation and ATP release induced by sodium arachidonate, ADP, or a combination of both were measured. Sodium arachidonate (0.25 mmol/L), which produces no platelet aggregation, combined with adenosine diphosphate (1 mumol/L), which produced a reversible platelet aggregation of 20% after ticlopidine, resulted in a synergistic platelet aggregation response in normal (74.6 +/- 9.2%) and in ticlopidine platelet-rich plasma (59.1% +/- 14.9%, p < 0.0001). Synergism after sodium arachidonate (0.75 mmol/L) plus adenosine diphosphate (4 mumol/L) fell from 75.8% +/- 11.0% and 59.1% +/- 15.6% after ticlopidine or aspirin, respectively, to 14.8% +/- 18.0% (p < 0.0001) after ticlopidine plus aspirin. Aspirin and ticlopidine alone did not inhibit adenosine triphosphate release as thoroughly as did aspirin plus ticlopidine. Aspirin or ticlopidine does not adequately prevent platelet activity as ticlopidine plus aspirin do. Addition of aspirin to treatment with ticlopidine improves their antiplatelet activity and better results could be obtained in arterial thrombotic prevention strategies.

Adenosine Triphosphate↗
PubMed1998

The septins are required for the mitosis-specific activation of the Gin4 kinase.

In budding yeast, a protein kinase called Gin4 is specifically activated during mitosis and functions in a pathway initiated by the Clb2 cyclin to control bud growth. We have used genetics and biochemistry to identify additional proteins that function with Gin4 in this pathway, and both of these approaches have identified members of the septin family. Loss of septin function produces a phenotype that is very similar to the phenotype caused by loss of Gin4 function, and the septins are required early in mitosis to activate Gin4 kinase activity. Furthermore, septin mutants display a prolonged mitotic delay at the short spindle stage, consistent with a role for the septins in the control of mitotic events. Members of the septin family bind directly to Gin4, demonstrating that the functions of Gin4 and the septins must be closely linked within the cell. These results demonstrate that the septins in budding yeast play an integral role in the mitosis-specific regulation of the Gin4 kinase and that they carry out functions early in mitosis.

Amino Acid Sequence↗
PubMed1998

Inter-observer reliability of the arthroscopic quantification of chondropathy of the knee.

BACKGROUND: Several scoring systems have been proposed in order to quantify the degree of cartilage damage observed by arthroscopy of the knee in patients with osteoarthritis. OBJECTIVE: To evaluate the inter-observer reliability of five different scoring systems of arthroscopic evaluation for chondropathy in osteoarthritis of the knee and to evaluate the utility of a training session between different observations on these scoring systems. METHODS: Videotapes of knee arthroscopies on five patients with osteoarthritis demonstrating different levels of severity of cartilage damage of the medial tibiofemoral compartment were analyzed by nine observers prior to (pre-training evaluation) and 2 months after a 6 h training session (post-training evaluation) by the following scoring systems: (1) cartilage deterioration by a 100 mm visual analogue scale (VAS), (2) overall assessment of degeneration in the entire medial compartment (cartilage, meniscus, osteophyte) using a 100 mm VAS, (3) French Society of Arthroscopy (SFA) Scoring System, (4) SFA Grading System, (5) American College of Rheumatology (ACR) Scoring System. RESULTS: At the pre-training evaluation, the SFA grading system produced the highest coefficient of reliability (r = 0.94), the other systems recording levels of < or = 0.80. At the post-training evaluation, the coefficient of reliability was r > 0.80 for four of the five scoring systems, with lack of improvement in the ACR Scoring System. CONCLUSION: There was an improved and acceptable inter-observer reliability for at least 2 months follow-up in four of five evaluated scoring systems of arthroscopically graded osteoarthritis of the knee following a training session. A scoring system using a 100 mm VAS may produce the best inter-observer reliability. These results show that scoring chondropathy is possible and demonstrate the importance of training in the analysis of articular cartilage breakdown.

Arthroscopy↗
PubMed1998

Anterior cervical osteophytes as a cause of pharyngeal stage dysphagia.

OBJECTIVE: To describe the association of anterior cervical osteophytes impairing epiglottic movement as an etiology of pharyngeal stage dysphagia. DESIGN: A retrospective chart review. SETTING: An academic affiliated Veterans Affairs Medical Center. PATIENTS: Veterans 60 years of age or older referred to speech pathology for dysphagia evaluation. RESULTS: Of 376 veterans evaluated consecutively since 1990, 40 patients had dysphagia determined to be secondary to cervical bony protuberances. The evaluation and management of three cases with functional consequences at level C3-5 with no dysphagia etiology present are described. CONCLUSION: Cervical osteophytes need to be considered in the differential diagnosis of dysphagia in older people.

Aged↗
PubMed1998

The relationship between psychotherapist and prescribing psychiatrist. Some considerations.

We have reviewed the vagaries and vicissitudes of an increasingly common arrangement in contemporary mental health treatment, namely, the collaboration between psychotherapist and prescribing psychiatrist in the treatment of the patient who requires both psychotherapy and pharmacotherapy. Such a collaboration raises practical, legal, transference, counter-transference, economic, and training issues. It is our hope that this review of these issues will lead to further discussion as, in our experience, they have until now received scant attention in the mental health literature, in the day-to-day work of practitioners, and in supervision and training. We believe that successful collaboration can be achieved when sufficient awareness and planning are present at the outset.

Humans↗