Oral anticoagulation reduces activated protein C less than protein C and other vitamin K-dependent clotting factors

Oral anticoagulant therapy, which is used for prophylaxis and management of thrombotic disorders, causes similar reductions in plasma levels of vitamin K-dependent procoagulant and anticoagulant clotting factor zymogens. When we measured levels of circulating activated protein C, a physiologically important anticoagulant and anti-inflammatory agent, in patients on oral anticoagulant therapy, the results unexpectedly showed that such therapy decreases levels of activated protein C substantially less than levels of protein C, prothrombin, and factor X, especially at lower levels of prothrombin and factor X. Thus, we suggest that oral anticoagulant therapy results in a relatively increased expression of the protein C pathway compared with procoagulant pathways not only because there is less prothrombin to inhibit activated protein C anticoagulant activity, but also because there is a disproportionately higher level of circulating activated protein C.     

Effects of pseudoephedrine on maximal cycling power and submaximal cycling efficiency

PURPOSE: To study the effects of a therapeutic dose of pseudoephedrine on anaerobic cycling power and aerobic cycling efficiency. METHODS: Eleven healthy moderately trained males (VO (2peak) 4.4 +/- 0.8 L x min(-1) participated in a double-blinded crossover design. Subjects underwent baseline (B) tests for anaerobic (Wingate test) and aerobic (VO (2peak) test) cycling power. Subjects ingested either 60 mg of pseudoephedrine hydrochloride (D) or a placebo (P) and, after 90 min of rest, a Wingate and a cycling efficiency test were performed. During the cycling efficiency test, heart rate (HR) and VO(2) were averaged for the last 5 min of a 10-min cycle at 40% and 60% of the peak power achieved during the VO (2peak) test. RESULTS: There were no significant differences in peak power (B = 860 +/- 154, D = 926 +/- 124, P = 908 +/- 118 W), total work (B = 20 +/- 3, D = 21 +/- 3, P = 21 +/- 3 kJ), or fatigue index (B = 39 +/- 8, D = 45 +/- 5, P = 43 +/- 5%). There were no significant differences in HR at 40% power (D = 138 +/- 10, P = 137 +/- 10 beats.min-1) or 60% power (D = 161 +/- 11, P = 160 +/- 11 beats x min(-1). There were no significant differences in cycling efficiency at 40% power (D = 18.8 +/- 1.8, P = 18.5 +/- 1.8%) or 60% power (D = 20.3 +/- 2.0, P = 20.1 +/- 2.1%). CONCLUSION: A therapeutic dose of pseudoephedrine hydrochloride does not affect anaerobic cycling performance or aerobic cycling efficiency.     

Diagnostic alertness to patients having a personality disorder with changing symptoms

The diagnosis of mood disorders in patients with a personality disorder is complex because there may be a significant overlap of symptomatology between both disorders. A 33-year-old man with a borderline personality disorder, for which he had been treated for several years with marginal success, developed a depression that was not recognised and treated until late. Besides the similarity between the two disorders, emotional and personal factors on the part of the physician played an important role in the failure to diagnose the depression. In such complex situations, the use of practice guidelines may be helpful because these prescribe professional attitudes that, in this case, would probably have prevented the non-recognition of the depression.     

Knowledge, attitudes, and practices related to the Pap smear among women with cervical cancer

Despite screening programs, Brazil has a high cervical cancer mortality rate. The objective of this cross-sectional study was to analyze knowledge, attitudes, and practices related to the Pap smear and to understand why women fail to submit to this screening test. A structured questionnaire was used to interview 138 women: 90 with high grade intraepithelial neoplasia and 48 with invasive cervical cancer. Inadequate practices were more frequent among women with invasive cancer. In terms of difficulties in obtaining medical care, more than 80% of women reported lack of motivation, 60% reported that physicians failed to conduct a complete physical examination, and some 50% reported that physicians' schedules were busy. Having a Pap smear usually depended on a physician's request and the woman being symptomatic. Women over than 56 years old showed more frequent inadequate knowledge, attitudes and practices. However, those with more schooling were more knowledgeable of the Pap smear procedure. Age and less schooling could be barriers against women participating in screening programs, but socioeconomic problems must also be considered for improving practices related to the Pap smear.     

Do we know which patients with the antiphospholipid syndrome should receive long-term high dose anti-coagulation?

The standard treatment of thrombosis related to antiphospholipid antibodies is lifelong high-intensity oral anticoagulation. This standard is primarily based on retrospective evaluations of such patients. In this paper we give a summary of current treatment of deep leg vein thrombosis, pulmonary embolism, ischaemic stroke and transient ischaemic events in the general population and relate this to studies performed in patients with the anti-phospholipid syndrome (APS). It is concluded that many patients with APS can be treated with conventional doses of oral anticoagulants, and that anti-platelet drugs may have a role in the prevention of cerebral ischaemic events. Data from large scale prospective studies, which are underway, will ultimately identify the optimal treatment in individual patients.     

Innovation, Peer Teaching, and Multidisciplinary Collaboration: Outreach from a School-Based Clinic

The gum-chewing 10th grade student with teased hair eyed the quiet line of seventh grade girls seated nervously across the table from her in the mid-school library. The 10th grade student was their “teacher” for the next 30 minutes, leading a discussion about AIDS. “So,” she asked, chewing between phrases, “You girls know about latex condoms?” She then rattled off a series of questions and teaching points about AIDS — “African green monkeys,” “unprotected sex,” “shared needles.” The 10th grade student was contributing to her inner city high school class project, run in conjunction with the school-based clinic. She was sharing her special knowledge about AIDS, taught by the clinic staff, with younger children as a service to her community. What this novice teacher was lacking in professional delivery she made up for in enthusiasm for both her subject and for her important, new leadership role.     

Comparison between theophylline and an adenosine non-blocking xanthine in acute asthma

Enprofylline, a drug without adenosine antagonism and theophylline, a potent adenosine antagonist, were compared, double-blind, randomized, in acute asthma (n = 33). The drugs were given intravenously as loading over 10 min followed by maintenance infusion for 24 h. Mean final plasma levels were very high with enprofylline (14 mg.l), and larger than calculated with theophylline (16 mg.l). Seven patients had maximum levels of enprofylline ranging between 16 and 42 mg.l. Extreme plasma levels of enprofylline were not associated with any theophylline-like central nervous system excitatory effects related to seizure-inducing ability. Some irregularities in the heart rhythm did not raise clinical problems and no significant difference between enprofylline and theophylline was recorded. At 1 h patients on enprofylline (mean plasma level: 5.7 mg.l) and theophylline (12.2 mg.l) had improved their peak expiratory flow rates by 31% and 15% (p less than 0.05), respectively. The improvement in lung function after 24 hours did not differ between treatments suggesting that the high levels of enprofylline were supramaximal for its anti-asthma effects in this situation. In conclusion, with enprofylline it is demonstrated that an adenosine non-blocking xanthine derivative may lack CNS-excitatory effects, but be more potent than theophylline in the treatment of acute asthma.     

Varicella zoster meningitis in a pregnant woman with acquired immunodeficiency syndrome

Between 6000 and 7000 women in the United States infected with human immunodeficiency virus (HIV) give birth annually. It is well known that HIV-related immunosuppression significantly increases the risk for acquiring opportunistic infections (OIs). However, there is limited information regarding the relationship of pregnancy in the setting of HIV/AIDS infection, subsequent development of OIs, and maternal and fetal outcomes. A pregnant 36-year-old woman with AIDS was diagnosed with varicella zoster meningitis. Weight-based therapy with acyclovir was initiated with clinical improvement in symptoms. Care of a pregnant HIV-infected patient with an OI poses a unique diagnostic and therapeutic challenge for clinicians. Early diagnosis and initiation of appropriate treatment may provide an opportunity to improve both maternal and fetal outcomes.     

The antiphospholipid antibody dilemma

Clinical Rheumatology - In evaluating the literature, we have to be aware of some important drawbacks of most studies: 1) the relation between aPLab and thrombosis has not yet been proven in...     

Detection and localization of silicon and associated elements in vertebrate bone tissue by imaging ion microscopy

Summary The growing long bones from normal embryonic chicks and young rats have been examinedin situ by imaging ion microscopy, a highly sensitive technique for elemental detection and localization. In tibial diaphyses from chick and rat, treated with anhydrous ethylene glycol, embedded in Spurr medium, and dry sectioned 1–2 μm thick, analyses revealed the presence of silicon, calcium, magnesium, carbon, and oxygen. Silicon localization was principally extracellular in the tissues. Comparison of single element maps of silicon and calcium indicated that silicon specifically appeared in putative uncalcified osteoid regions of tibiae. Detection and imaging of silicon by ion microscopy support results of earlier work by Carlisle [3], who demonstrated the element in osteoid of rat and mouse bone by electron probe microanalysis. The current data offer the possibility for characterizing more completely silicon interaction in vertebrate calcified tissues.