Impact of clinical history on fracture detection with radiography

The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.     

An experimental model for the combined medical and surgical treatment of gallstones

Summary New approaches to the treatment of gallstone disease have been introduced in recent years. In addition to bile acid dissolution, a chemical solvent (methyl tertiary-butyl ether) has been instilled directly into the gallbladder by percutaneous transhepatic techniques. Shock wave fragmentation of stones, induced by extracorporeal techniques or contact catheter probe placement, have also been successfully employed. Recurrence of gallstones, however, can be anticipated in most of these patients with an intact gallbladder and continued hepatic production of lithogenic bile. In order to explore these new procedures and to attempt to find a solution to the problem of stone recurrence, an animal model has been developed. The essential components of this model consist of an endoscopic (laparoscopic) cholecystopexy and, at a later date, percutaneous re-entry into the gallbladder by dilation of the cholecysto-cutaneous tract and the use of electrohydraulic and ultrasonic lithotripsy and methyl tertiary-butyl ether to achieve stone dissolution.     

Dose-response relationship between objective measures of histamine-induced weals and dose of terfenadine.

Terfenadine is a safe non-sedative H1-receptor antagonist. This study aimed to quantify the relative reduction in weal and flare area, thickness and erythema at 4, 8, 12 and 24 h following a single but variable oral dose of terfenadine compared with pre-treatment measurements, in order to compare the dose-effect relationship and time course of the different dosages. In a double-blind randomized cross-over study, 12 healthy volunteers were given 60, 120 or 240 mg of terfenadine or placebo. Twenty micrograms of histamine acid phosphate was then injected intradermally at 4, 8, 12 and 24 h. The weal and flare areas were measured by planimetry, the thickness of the weal by an A-scan pulsed ultrasound device and the redness of both the weal and flare by an erythema-meter. A definite dose-response relationship was demonstrated between the weal and flare areas and the three active treatments. For the weal area, there was a significant difference between 60 mg and 240 mg of terfenadine at 4 h (p less than 0.01), at 8 and 12 h (p less than 0.05). For the flare area there was a similar significant difference at 4 h (p less than 0.01) and at 8 h (p less than 0.05). A dose-response relationship was demonstrated between weal erythema and 120 mg or 240 mg and 60 mg of terfenadine (p less than 0.05). There was a correlation between the plasma levels of the major metabolite and the initial dose of terfenadine, demonstrating their expected proportionality. This metabolite was also demonstrated in tissue fluid.     

In vitro activity of clindamycin and other antimicrobials against gram-positive bacteria and Hemophilus influenzae.

Summary: Seven antimicrobials--clindamycin, penicillin, ampicillin, cloxacillin, erythromycin, lincomycin and cephalexin--were found to have a high degree of activity in vitro against 256 isolates of gram-positive bacteria and Hemophilus influenzae. Clindamycin was clearly superior against staphylococci and 3.12 mug/ml or less of clindamycin inhibited all 35 isolates of H. influenzae. Synergism was not demonstrated when clindamycin was tested in combination with sulfisoxazole or sulfamethoxazole by either the agar dilution or 24-hour growth curve method. This was true for penicillin as well, and the effect was independent of sulfonamide sensitivity. The erythromycin-sulfonamide combination was synergistic against 6 of 10 strains studied by the growth curve method; this effect was not demonstrable by the agar dilution method.     

A review of the epidemiology of tinea unguium in the community

Tinea unguium is a common, chronic fungal infection of the nails. Many epidemiological studies have looked at the frequency with which this condition is seen in hospital outpatients clinics or mycological laboratories along with other dermatomycoses. Only recently have studies begun to emerge looking at the prevalence of this condition in populations. Hospital and mycological laboratory-based studies give valuable information about tinea unguium prevalence in a particular clinic, but cannot be compared with other studies due to confounding factors inherent in the different people attending individual clinics. From population-based studies the prevalence of tinea unguium lies between 2 and 8%. Tinea unguium increases steadily with age. It is infrequent but definitely found in children. With the increasing life expectancy in the Western world the prevalence of tinea unguium is likely to increase further without adequate prevention and treatment.     

A preliminary report of the occupation of patients evaluated in patch test clinics.

BACKGROUND: The interplay between the occupational environment and worker's skin can result in contact dermatitis of both irritant and allergic types. Other forms of dermatitis can also be influenced by occupational exposures. OBJECTIVE: The aim of this study is to compare the occupations and allergens of occupational contact dermatitis cases with nonoccupational contact dermatitis cases. METHODS: Diagnostic patch testing with allergens of the North American Contact Dermatitis Group and occupational coding by the National Institute for Occupational Safety and Health methods. RESULTS: Of 2,889 patients referred for evaluation of contact dermatitis, 839 patients (29%) were found to have occupational contact dermatitis. Of the 839 cases deemed occupational, 455 cases (54%) were primarily allergic in nature and 270 cases (32%) were primarily irritant in nature. The remaining 14% were diagnoses other than contact dermatitis, aggravated by work. The occupation most commonly found to have allergic contact dermatitis was nursing. Allergens strongly associated with occupational exposure were thiuram, carbamates, epoxy, and ethylenediamine. CONCLUSION: Some contact allergens are more commonly associated with occupational contact dermatitis. Nursing and nursing support are occupations most likely to be overrepresented in contact dermatitis clinics.     

Cat hindlimb motoneurons during locomotion. III. Functional segregation in sartorius

Cat sartorius has two distinct anatomical portions, anterior (SA-a) and medial (SA-m). SA-a acts to extend the knee and also to flex the hip. SA-m acts to flex both the knee and the hip. The objective of this study was to investigate how a "single motoneuron pool" is used to control at least three separate functions mediated by the two anatomical portions of one muscle. Discharge patterns of single motoneurons projecting to the sartorius muscle were recorded using floating microelectrodes implanted in the L5 ventral root of cats. The electromyographic activity generated by the anterior and medial portions of sartorius was recorded with chronically implanted electrodes. The muscle portion innervated by each motoneuron was determined by spike-triggered averaging of the EMGs during walking on a motorized treadmill. During normal locomotion, SA-a exhibited two bursts of EMG activity per step cycle, one during the stance phase and one during the late swing phase. In contrast, every recorded motoneuron projecting to SA-a discharged a single burst of action potentials per step cycle. Some SA-a motoneurons discharged only during the stance phase, whereas other motoneurons discharged only during the late swing phase. In all cases, the instantaneous frequencygram of the motoneuron was well fit by the rectified smoothed EMG envelope generated by SA-a during the appropriate phase of the step cycle. During normal locomotion, SA-m exhibited a single burst of EMG activity per step cycle, during the swing phase. The temporal characteristics of the EMG bursts recorded from SA-m differed from the swing-phase EMG bursts generated by SA-a.(ABSTRACT TRUNCATED AT 250 WORDS)     

Nocturia: a risk factor for falls in the elderly.

OBJECTIVE: To determine if nocturia is a risk factor for reported falls and bone fractures in older persons. DESIGN: Cross-sectional study comparing falls in men and women with and without nocturia. SETTING: Longitudinal health screening program of ambulatory elderly participants. PARTICIPANTS: Participants included 988 (65.5%) women and 520 (34.5%) men who had completed their tenth annual visit to the program. MAIN OUTCOME MEASURES: Reported falls in the past year and reported bone fractures in the past 5 years. RESULTS: Participants who reported nocturia at least twice during the night were at significantly greater risk to report falls (Odds Ratio = 1.84; 95% CI = 1.05-3.22), and the risk increased in subjects reporting more than three nocturia events (Odds Ratio = 2.15; 95% CI = 1.04-4.44). The significant increase in falls reported by nocturia participants did not result in an increase in reported bone fractures in the past 5 years (P < 0.4360). CONCLUSIONS: Nocturia is an important risk factor for falls in ambulatory elderly persons. Preventive measures should be taken to decrease nocturia events and to decrease the risk of falling during these nocturia events.     

Effect of glucagon antibodies on plasma glucose,insulin and somatostatin in the fasting and fed rat

Summary A potent high-titre glucagon antibody pool was used to induce a state of acute glucagon deficiency in order to investigate the importance of glucagon in maintaining euglycaemia in the fed and fasted anaesthetised rat. Binding characteristics of the antiserum and evidence of its neutralisation of the biological effects of exogenous glucagon are described. The amount of antibody administered was capable of neutralising up to 12 times the total content of glucagon (approximately 1nmol) in the rat pancreas. The hyperglycaemic response to 1.43 nmol exogenous glucagon was significantly inhibited in the rat by glucagon antibodies given intravenously or intraperitoneally (p < 0.001). However, no changes in plasma glucose occurred in rats fasted 16 h (4.35±0.1 mmol/l or 24 h (4.0±0.05 mmol/l) after antibody administration. The same dose of glucagon antibodies produced no change in plasma glucose (6.1±0.2 mmol/l), immunoreactive insulin (1.85±0.05 g/l) or immunoreactive somatostatin (110±30 ng/l) in rats after antibody administration. Antibody excess, equivalent to a binding capacity for glucagon of 40 nmol/l in the plasma of recipient animals, was demonstrable at all times after passive immunisation. The absence of any affect on glucose concentrations following immunoneutralisation of glucagon suggests that glucagon secretion may not be a major factor in the maintenance of euglycaemia in the rat.