Landing limb posture in volleyball athletes with patellar tendinopathy: a pilot study.

The aims of this pilot study were to investigate how a novel sagittal plane kinematic measurement - the lower extremity contact angle (LECA) - relates to the landing dynamics of elite male volleyball athletes with and without patellar tendinopathy. The LECA was defined as the angle between the ground and the line connecting the center of pressure to the L5S1 marker. 18 athletes (9 with patellar tendinopathy and 9 with asymptomatic tendons) completed simulated spike jumps while instrumented for kinetic and kinematic analysis using a force platform and 3D motion analysis system. The patellar tendinopathic group demonstrated a significantly more acute LECA compared to the asymptomatic group (65.3°±2.2° vs. 69.1°±4.5°) and was the only kinematic or kinetic variable measured to discriminate between the 2 groups. The LECA further demonstrated less variability between trials than sagittal plane hip, knee, and ankle kinematics. Additionally, the LECA's - and not individual joints' - high correlation with the braking impulse ensures its predictive value for landing dynamics (r=- 0.890). The LECA has the potential to be a valuable tool to help assess jumping athletes in both injury prevention screening and as a variable that, if modified, could help alter the maladaptive behavior observed in symptomatic athletes.

Patellar tendon morphology in volleyball athletes with and without patellar tendinopathy.

Appropriate management of patellar tendinopathy requires distinguishing between inflammatory and degenerative conditions, often difficult because tendon thickening can be a normal or pathological adaptation, and micromorphology is not observable on clinical imaging. The purpose of this study was to quantitatively examine patellar tendon micro- and macromorphology in volleyball athletes and relate those findings to reported symptoms. Longitudinal ultrasound images of proximal and distal patellar tendons were acquired from 84 male elite volleyball athletes (44 symptomatic, 40 asymptomatic) and 10 asymptomatic nonathlete controls. Micromorphology was determined using two-dimensional Fast Fourier Transform analysis providing a discriminating peak spatial frequency parameter (PSF). Macromorphology (patellar tendon thickness) was measured using Image J software. All athletes regardless of symptoms had thicker proximal tendons compared to nonathletes, suggesting a normal adaptation to training loads. However, symptomatic athletes demonstrated lower PSF than asymptomatic athletes and nonathletes at the proximal tendon, suggesting greater collagen disorganization, and tendon degeneration rather than inflammation. Only symptomatic athletes had thicker distal tendons than nonathletes, but there was no difference in PSF distally. Diagnostic ultrasound enhances the understanding of the micromorphology of patellar tendons, supporting the rationale for management that remodels the degenerated tendon instead of treating inflammation.

New look at the metabolism of nonsteroidal anti-inflammatory drugs: influence on human serum albumin antioxidant activity.

Body's homeostasis is dependent on many factors, such as maintaining balance between free radicals formation and degradation. Human serum albumin (HSA) also plays an important role in homeostasis. The aim of this study was thermodynamic analysis of the interaction between ketoprofen (KET), naproxen (NPX), diclofenac (DIC) and HSA, as well as the effect of drug-albumin binding on HSA antioxidant activity using calorimetric and spectrophotometric techniques. Based on the calorimetric analysis it has been shown that accompanied by hydrophobic interaction drugs-albumin binding is an exoenergetic reaction. All analyzed drugs and HSA showed the ability to react with free radicals such as a radical cation, formed as a result of the reaction between 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and potassium persulfate (K2S2O8). Using ABTS assay a synergistic effect of ketoprofen (KET) and naproxen (NPX) on HSA antioxidant activity was observed while the effect of diclofenac (DIC) binding with albumin was probably additive. Because some medications including KET, NPX and DIC belong to over the counter (OTC) non-steroidal anti-inflammatory drugs (NSAIDs), it is necessary to understand their influence on HSA antioxidant activity.Communicated by Ramaswamy H. Sarma.

Physical and functional association of the major histocompatibility complex class I heavy chain alpha3 domain with the transporter associated with antigen processing.

CD8+ T lymphocytes recognize antigens as short, MHC class I-associated peptides derived by processing of cytoplasmic proteins. The transporter associated with antigen processing translocates peptides from the cytosol into the ER lumen, where they bind to the nascent class I molecules. To date, the precise location of the class I-TAP interaction site remains unclear. We provide evidence that this site is contained within the heavy chain alpha3 domain. Substitution of a 15 amino acid portion of the H-2Db alpha3 domain (aa 219-233) with the analogous MHC class II (H-2IAd) beta2 domain region (aa 133-147) results in loss of surface expression which can be partially restored upon incubation at 26 degrees C in the presence of excess peptide and beta2-microglobulin. Mutant H-2Db (Db219-233) associates poorly with the TAP complex, and cannot present endogenously-derived antigenic peptides requiring TAP-dependent translocation to the ER. However, this presentation defect can be overcome through use of an ER targeting sequence which bypasses TAP-dependent peptide translocation. Thus, the alpha3 domain serves as an important site of interaction (directly or indirectly) with the TAP complex and is necessary for TAP-dependent peptide loading and class I surface expression.

Reversal of prolonged isoniazid-induced coma by pyridoxine.

Isoniazid overdose is known to result in the rapid onset of seizures, metabolic acidosis, and prolonged obtundation. Pyridoxine has been reported to be effective in treating isoniazid-induced seizures. We report three cases of obtundation secondary to isoniazid overdose that was immediately reversed by intravenous pyridoxine. In two of these cases, status seizures were stopped by intravenous pyridoxine administration, but the patients remained comatose for prolonged periods. The comas were immediately reversed by the administration of additional pyridoxine. In the third case, the patient's lethargy was treated by intravenous pyridoxine on presentation and was followed by immediate awakening. Pyridoxine is effective in treating not only isoniazid-induced seizures, but also the mental status changes associated with this overdose. The dose required to induce awakening may be higher than that required to control seizures.

Predictors of coronary artery disease in patients with cocaine-associated myocardial infarction. Cocaine-Associated Myocardial Infarction (CAMI) Study Group.

PURPOSE: To identify clinical criteria predictive of underlying coronary artery disease in patients with cocaine-associated myocardial infarction. PATIENTS AND METHODS: Using a retrospective cross-sectional study design at 29 acute care hospitals, we identified 70 patients with cocaine-associated myocardial infarction who had a determination of the presence or absence of coronary artery disease. Clinical characteristics of patients with coronary artery disease (> 50% stenosis on cardiac catheterization or reversible ischemia on stress test) were compared with patients without coronary artery disease (< 50% stenosis on cardiac catheterization). RESULTS: Compared with patients without coronary artery disease (n = 21), patients with coronary artery disease (n = 49) were older (42 versus 31 years; P < 0.001), had more traditional cardiac risk factors (2.3 versus 1.5; P < 0.001), more frequent history of hypertension (odds ratio [OR], 5.3; 95% confidence interval [CI], 1.4 to 20.4); more frequent family history of myocardial infarction (OR, 4.4; 95% CI, 1.3 to 15.1), more bradydysrhythmias (OR, 8.0; 95% CI, 1.0 to 65.5), and more likely to have an inferior infarct location (P = 0.04). CONCLUSION: Age, number of cardiac risk factors, location of myocardial infarction, and bradydysrhythmias predict underlying coronary artery disease in patients with cocaine-associated myocardial infarction. If validated, this knowledge may be used to develop a medically appropriate, cost-effective evaluation strategy for patients following cocaine-associated myocardial infarction.

Cyanide poisoning from laetrile ingestion: role of nitrite therapy.

A 4-year-old child ingested laetrile and almost died of cyanide poisoning. Treatment with the Lilly cyanide antidote kit resulted in rapid, complete recovery. Extremely high whole blood cyanide levels were documented. The necessity for use of the antidote kit in serious cyanide poisoning has recently been questioned. This case demonstrates benefit from antidotal treatment.

Fluoride ingestion in children: a review of 87 cases.

All cases of fluoride ingestion in children younger than 12 years old reported to the Rocky Mountain Poison Center between January 1 and December 31, 1986, were retrospectively reviewed. Eighty-seven cases were identified. Eighty-four cases involved accidental ingestion of dental fluoride products in the home (tablets, drops, rinses) in children 8 months to 6 years old. Two older children (8 and 9 years old) became symptomatic after fluoride treatment by a dentist. A 13-month-old child died after ingesting an unknown amount of sodium fluoride insecticide, the only insecticide exposure in our series. Postmortem total serum calcium value was 4.8 mg/dL (normal 8.8 to 10.3). No other patients had serious symptoms or sequelae. Twenty-six (30%) of 87 became symptomatic, with gastrointestinal symptoms (nausea, vomiting, diarrhea, abdominal pain) in 25 patients and drowsiness in 1. Only 3 patients became symptomatic later than 1 hour after ingestion. Analysis of data from 70 cases with sufficient information revealed that as the amount of fluoride ingested increased, the percentage of patients with symptoms increased. Not including the fatal case, 6 patients had serum calcium levels measured, and all were normal. Children who ingested up to 8.4 mg/kg of elemental fluoride in dental products had mild and self-limited symptoms, mostly gastrointestinal.

Superwarfarin poisoning in children: a prospective study.

This prospective study was undertaken to determine the incidence, severity, time of onset, and duration of coagulopathy in children following accidental ingestion of long-acting anticoagulant rodenticides, often called "superwarfarins." Of 110 children, who ingested superwarfarins and in whom one or more prothrombin time values were obtained, 8 had a prothrombin time ratio (patient to control) of greater than or equal to 1.2, indicative of anticoagulation. Prothrombin time values obtained 48 hours after ingestion were more likely to be prolonged (6/34, 17.6%) than values obtained 24 hours after ingestion (2/104, 1.9%) (P less than .005). The occurrence of an abnormal prothrombin time could not be predicted based on the history of amount ingested or on the presence of the characteristic green-blue product dye in or around the child's mouth. Acute toxicity was evidenced by transient abdominal pain, vomiting, and heme positive stools in 2 patients. The duration of prothrombin time prolongation could not be determined because of the few values obtained after 48 hours. To detect all possible abnormal prothrombin time values, 24- and 48-hour determinations are recommended after a child has ingested a superwarfarin.

Bromocriptine-associated headache: possible life-threatening sympathomimetic interaction.

We present two cases of severe headache associated with the use of bromocriptine for lactation suppression in otherwise healthy women. In each case, the additional use of a therapeutic sympathomimetic agent resulted in extreme worsening of symptoms with development of hypertension and life-threatening complications (ventricular tachycardia and cardiac dysfunction in one case, seizures and cerebral vasospasm in the other). Sympathomimetics in combination with bromocriptine in patients with a bromocriptine-associated headache during the puerperium may be dangerous.

Acute acetaminophen overdose during pregnancy.

During a nationwide acetaminophen overdose study conducted at the Rocky Mountain Poison and Drug Center from 1976-1985, 113 patients entered into the study were reported to be pregnant at the time of the overdose. Follow-up, including appropriate laboratory and pregnancy outcome data, was available in 60 cases. Of these, 19 women overdosed during the first trimester, 22 during the second trimester, and 19 during the third trimester of pregnancy. Of the 24 patients with acetaminophen levels above the acetaminophen overdose nomogram line, ten were treated with N-acetylcysteine within 10 hours post-ingestion; eight delivered normal infants and two had elective abortions. Of ten patients treated with N-acetylcysteine 10-16 hours post-ingestion, five delivered viable infants, two had elective abortions, and three had spontaneous abortions. Of four women treated with N-acetylcysteine 16-24 hours post-ingestion, one mother died, and there was one spontaneous abortion, one stillbirth, one elective abortion, and one delivery. Multiple logistic regression demonstrated a statistically significant correlation between the time to loading dose of N-acetylcysteine and pregnancy outcome, with an increase in the incidence of spontaneous abortion or fetal death when treatment was begun late. We recommend that pregnant women who take an acetaminophen overdose and have a potentially toxic serum level be treated with N-acetylcysteine as early as possible.

Peptide loading of nascent MHC class I molecules.

A critical molecular interaction during assembly of the major histocompatibility complex (MHC) class I molecules takes place between the heavy chain and the transporter-associated with antigen-processing (TAP) complex. The recent mapping of regions of the heavy chain involved in the binding to TAP suggests a complex molecular interaction essential for the cell surface expression of the MHC class I. The advances made in understanding the TAP-MHC class I interaction are reviewed and discussed here.

Acute medical costs of fluoxetine versus tricyclic antidepressants. A prospective multicentre study of antidepressant drug overdoses.

Despite demonstrated differences in toxicity profiles between tricyclic antidepressants (TCAs) and selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs), no studies have examined hospital costs associated with acute antidepressant overdoses. Given the high incidence of such overdoses, it is important to examine treatment patterns and associated costs. This prospective, multicentre cohort study compared the hospital and physician costs associated with TCA and fluoxetine drug overdoses. Over a 30-month period, 622 consecutive patients with a fluoxetine or TCA overdose presented to the emergency departments, or were admitted to intensive care or medical units, of 9 participating medical centres across the US. Inclusion criteria were: ingestion of a single antidepressant (fluoxetine or a TCA), without clinically significant co-ingestants; laboratory confirmation of the overdose; and retrievable hospital bills. Patients were followed until discharge from the emergency department or hospital. Hospital and physician charges were collected from billing data. Hospital charges were adjusted using Health Care Financing Administration cost: charge ratios to estimate costs; physician charges were adjusted to estimate costs. Patient demographic and clinical data were prospectively gathered during the course of medical treatment. Clinical data recorded included level of consciousness, cardiopulmonary complications, vital sign or ECG abnormalities, agitation, seizures, CNS depression and death. 136 patients (121 with TCA overdose and 15 with fluoxetine overdose), representing 21.8% of the 622 patients entered, met the inclusion criteria. Mean length of stay varied from 0.73 [+/-standard error of the mean (SEM) 0.33] days for fluoxetine overdose patients to 3.59 (+/-SEM 0.48) days for TCA overdose patients (p = 0.038). Mean hospital costs were $US668 for patients with a fluoxetine overdose compared with $US4691 for those with a TCA overdose (p < 0.0001). No significant differences were observed between the TCA and fluoxetine overdose groups with regard to physician costs. Median hospital and physician costs increased from $US3029 to $US4396 from the first 15-month period of the study to the second 15-month period of the study for the TCA overdose group, but decreased from $US881 to $US396 for the fluoxetine overdose group. Patients with fluoxetine overdoses had lower hospital and total medical costs compared with patients with TCA overdoses. There was some evidence supporting a reduction in the medical costs of treating fluoxetine overdoses over the 30-month study period.

The effects of eccentric velocity on activation of elbow flexors: evaluation by magnetic resonance imaging.

PURPOSE: To compare magnetic resonance imaging (MRI) signal intensity changes in the primary elbow flexors during two isotonic exercise protocols varying in eccentric velocity and the ratio of eccentric to concentric activity. METHODS: Twelve men performed two exercise protocols. The right and left arms were randomly assigned to one of two protocols that had the same workload (60% 1RM) and same total time of exercise (144 s) but differed in the velocity and ratio of eccentric to concentric activity (1:1 and 5:1 for the fast and slow protocols, respectively). MRI signal intensity changes were quantified pre- and post-exercises using an inversion recovery sequence with a 1.5T MRI system (TR = 2500 ms, TE = 90 ms, TI = 140 ms). Percent change in MRI signal intensity, rate of perceived exertion (RPE), and delayed onset muscle soreness (DOMS) were recorded and analyzed. RESULTS: The biceps brachii was found to be preferentially recruited during the fast protocol compared with the brachialis, whereas the brachialis was found to be preferentially recruited during the slow protocol (P < 0.05). The fast exercise protocol was perceived as being more strenuous (RPE = 8.3 +/- 2.1) than the slow (RPE = 5.4 +/- 1.5, P < 0.05) and produced DOMS in 58% of the tested subjects. CONCLUSIONS: These results suggest that agonists respond to various loading conditions nonhomogeneously. These findings may have implications with respect to exercise prescriptions for specific muscles.

Clinical teaching in physical therapy: student and teacher perceptions.

Many practicing physical therapists participate in the most crucial phase of a student's education by serving as Clinical Instructors. The purposes of this study were to identify the clinical teaching behaviors perceived as most effective and most hindering by students and CIs and to compare the response rates of students in bachelor's and master's degree programs. A published 58-item questionnaire was completed by 172 participants from eight physical therapy education programs. The results were analyzed by multivariate analysis of variance. The perceived most helpful teaching behaviors pertained to providing information through feedback. The perceived most hindering behaviors were intimidating questioning and correcting student errors in the presence of patients. The different student and CI ratings for the item "leaves student alone until asked to supervise" has important ethical and educational implications. Master's and bachelor's degree students' ratings differed significantly on four teaching behaviors. Different instructional methods might be necessary for educating these students.

LSD.

LSD is still readily available in the United States as a street drug of abuse. Emergency physicians may be called on to diagnose acute LSD intoxication in cases in which the history is unavailable. The typical LSD intoxication syndrome causes marked illusions of color and sound, along with a feeling of "cosmic awareness." True hallucinations only occasionally occur; the pupils invariably are massively dilated. The diagnosis may be very difficult to establish when other drugs, particularly those causing coma, are present. The toxicology laboratory can now easily detect LSD by radioimmunoassay.

The other alcohols. Methanol, ethylene glycol, and isopropanol.

The alcoholic patient, in an attempt to maintain an altered mental status, may ingest ethanol substitutes containing methanol, ethylene glycol, or isopropanol. The subsequent clinical presentation in the Emergency Department is highly variable and depends on the ethanol substitute ingested, the time since ingestion, and concomitant ethanol abuse. This article describes the clinical features of intoxication by the ethanol substitutes. Early diagnosis and therapeutic intervention may prevent irreversible sequelae. The rationale for treatment interventions is discussed.

The effect of level of spinal cord injury on shoulder joint kinetics during manual wheelchair propulsion.

OBJECTIVE: The effects of spinal cord injury level on shoulder kinetics during manual wheelchair propulsion were studied. DESIGN: Single session data collection in a laboratory environment. METHODS: Male subjects were divided into four groups: low level paraplegia (n=17), high level paraplegia (n=19), C7 tetraplegia (C7, n=16) and C6 tetraplegia (C6, n=17). Measurements were recorded using a six-camera VICON motion analysis system, a strain gauge instrumented wheel, and wheelchair ergometer. Shoulder joint forces and moments were calculated using the inverse dynamics approach. RESULTS: Mean self-selected propulsion velocity was higher in the paraplegic (low paraplegia=90.7 m/min; high paraplegia=83.4 m/min) than tetraplegic (C7=66.5 m/min; C6=47.0 m/min) groups. After covarying for velocity, no significant differences in shoulder joint moments were identified. However, superior push force in subjects with tetraplegia (C7=21.4 N; C6=9.3 N) was significantly higher than in those with high paraplegia (7.3 N), after covarying velocity. CONCLUSIONS: The superior push force in the tetraplegic groups coupled with weakness of thoraco-humeral depressors increases susceptibility of the subacromial structures to compression. RELEVANCE: Increased vertical force at the shoulder joint, coupled with reduced shoulder depressor strength, may contribute to shoulder problems in subjects with tetraplegia. Wheelchair design modifications, combined with strength and endurance retention, should be considered to prevent shoulder pain development.

Cimetidine as adjunctive treatment for acetaminophen overdose.

The aim of this study was to determine if cimetidine in addition to N-acetylcysteine and standard supportive care provide additional hepatoprotection following acute acetaminophen poisoning. It was designed as a prospective study with alternate month treatment protocol, and the work was carried out at a regional certified poison information centre. For a 2-year period, consultations received by the Rocky Mountain Poison Center involving acute acetaminophen overdose patients with a serum level above the nomogram line, but who would not receive N-acetylcystine therapy until at least 8 h postingestion, were prospectively evaluated for adjunctive treatment with cimetidine. All patients received standard supportive therapy and N-acetylcysteine treatment. During odd numbered months, cimetidine 300 mg was administered intravenously every 6 h for the duration of N-acetylcysteine therapy. Forty-one cimetidine treated patients were compared to 66 patients in the control group. The peak measured AST levels (+/- s.e.) were 1259+/-330 and 1301+/-451 for the control and cimetidine treatment groups, respectively (P = 0.94). Fourteen of 64 patients (21%) in the control group and 8/41 patients (20%) in the cimetidine group developed an AST > 1000 IUL-1. There were no statistical differences between the cimetidine-treated and control groups when classified by AST < 100 IUL-1, 100-1000 IUL-1, or > 1000 IUL-1. The addition of cimetidine therapy to standard N-acetylcysteine treatment did not provide additional hepatoprotection in acutely acetaminophen poisoned patients when treatment was started later than 8 h post overdose.(ABSTRACT TRUNCATED AT 250 WORDS)

Cocaine adsorption to activated charcoal in vitro.

Although activated charcoal (AC) is commonly used after ingestions of cocaine, the ability of AC to bind with this drug is unknown. We studied binding of cocaine to AC in vitro. Cocaine adsorption to charcoal for AC:drug ratios of 1:1, 2.5:1, and 5:1 at pH 1.2 was 40%, 92%, and 99%, respectively; at pH 8.0, it was 78%, 98%, and 99%, respectively. All means were significantly different (P less than 0.05) versus the control (no AC) at each pH. At the AC:drug ratio of 1:1, there was also significantly greater adsorption of cocaine at pH 8.0 than at pH 1.2. This study shows that AC strongly adsorbs cocaine under both acidic and alkaline conditions.