Abnormal immunoglobulin G subclass production in response to keyhole limpet haemocyanin in atopic patients.

A proportion of patients with atopic dermatitis have elevated serum levels of IgG4. In order to investigate further this abnormality of IgG subclass production, atopic patients were immunized with the protein antigen keyhole limpet haemocyanin (KLH), and IgG subclass responses following primary and secondary immunization were analysed. In the primary response, titres of IgG1, 2 and 3 antibodies were lower in the atopic patients than in the controls. In contrast, titres of IgG4 were much higher for the patient group. In both patients and controls, the kinetics of IgG4 antibody production following the initial immunization with KLH showed a slow rise reaching a peak at 30 weeks. This time course indicated that the high IgG4 response was unlikely to be due to previous exposure of the patients to a cross-reacting antigen. A higher proportion of IgG4 was also seen in the atopic patients following secondary immunization; indeed, IgG4 was the major subclass in the secondary response in the patient group. In the controls, but not in the patients, titres of IgG4 anti-KLH correlated with total serum levels of IgG4, and some of the highest IgG4 antibody responses were detected in atopic patients whose serum IgG4 concentration was in the normal range. The results suggest that raised serum levels of IgG4 in atopy may reflect abnormal isotype regulation in response to protein antigens.


Production of reactive nitrogen intermediates by bone marrow-derived macrophages on treatment with cisplatin in vitro.

L929 culture medium (a source of macrophage colony stimulating factor (M-CSF) or recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF)-derived bone marrow macrophages treated with cisplatin or lipopolysaccharide (LPS) (10 micrograms/ml) were effective in the production of L-arginine-dependent reactive nitrogen intermediates (RNI) and generation of tumouricidal activity. The abilities of RNI secretion and related tumouricidal activity against P815 mastocytoma cells were compared. These parameters were found to be closely correlated in various experiments. RNI secretion and generation of bone marrow macrophage-mediated tumouricidal activity were significantly inhibited by L-N-monomethyl arginine (L-NMMA), a specific inhibitor of the L-arginine pathway, but L-NMMA did not inhibit macrophage-mediated killing of tumour necrosis factor (TNF)-sensitive Wehi cells, suggesting that activated macrophages exhibit at least two cytolytic mechanisms, one by L-arginine-dependent nitric oxide pathway and another by TNF-mediated killing. The present findings suggest that the mechanism of tumour cell killing by activated macrophages may differ, depending on the tumour cell type, and reactive nitrogen intermediates play a major role in cisplatin-mediated activation of bone marrow-derived macrophages.


Regulation of proximal tubule function by angiotensin.

1. Independent of its effects on renal haemodynamics and glomerular filtration, angiotensin II (AII) has direct actions on the proximal tubule involving transepithelial Na+, H+, HCO3-, and water reabsorption, ammoniagenesis, gluconeogenesis and renal growth. 2. The effects of AII on water and electrolyte transport are biphasic and dose-dependent, such that low concentrations (10(-12)-10(-9) mol/L) stimulate reabsorption whereas high concentrations (10(-7)-10(-6) mol/L) inhibit reabsorption. Similar dose-response relations have been obtained for luminal and peritubular addition of AII. 3. The cellular responses to AII are mediated via an AT-1 receptor coupled via G-regulatory proteins to several parallel signal transduction pathways. Low doses inhibit the basolateral adenylate cyclase, lower intracellular cAMP and withdraw the inhibitory effect of protein kinase A on the luminal Na/H exchanger. Stimulation of this exchanger may also occur due to AII-receptor activation of phospholipase C to release diacyl glycerol, or by local transduction in the brush-border membrane involving phospholipase A2. 4. Inhibition of proximal fluid reabsorption is associated with increased intracellular Ca2+ released from intracellular stores, or entering via voltage-sensitive channels in response to the release of inositol-1,4,5-trisphosphate, or following Ca2+ channel opening induced by the arachidonic acid metabolite 5,6-epoxy-eicosatrienoic acid. 5. The stimulatory actions of peritubular AII on proximal transport are inhibited by physiological concentrations of atrial natriuretic factor (ANF) and by parathyroid hormone (PTH). 6. It is concluded that intrarenal AII acts to maintain optimal matching of fluid reabsorption and filtered load in response to changes in sodium balance, as well as to promote acidification of the urine during acidosis and perhaps to potentiate tubular growth following renal injury.


Failure of the nitrous oxide tissue equilibration method for the determination of brain and myocardial blood flow under controlled conditions.

1. Two adult merino ewes were prepared with intravascular cannule for sampling aortic root blood, sagittal sinus blood and coronary sinus blood. 2. One week after preparation the animals were anaesthetized then ventilated with a gas mixture containing 10% nitrous oxide (N2O) for 60 min. Serial measurements of brain and myocardial blood flow were made using the N2O tissue equilibration method of Kety and Schmidt. 3. N2O failed to achieve matching arteriovenous blood concentration equality and saturation of the relevant tissues. Valid use of the Kety-Schmidt method, therefore, could not be confirmed. 4. Because of the failure of the arteriovenous equilibration, serially determined brain and myocardial blood flows were found to decrease with time. 5. The use of this method in circumstances where tissue saturation with the indicator gas cannot be ascertained is arbitrary.


Sodium and noradrenaline in cerebrospinal fluid and blood in salt-sensitive and non-salt-sensitive essential hypertension.

1. The effects of dietary sodium on blood pressure and levels of sodium, other electrolytes and noradrenaline (NA) in the cerebrospinal fluid (CSF) and blood of 15 patients with essential hypertension were studied. The CSF and blood sampling was carried out after 7 days of a high salt intake (16-18 g/day) and after 7 days of a low salt intake (1-3 g/day). 2. Blood pressure and sodium concentrations in CSF and serum were significantly higher in the high salt period than the low salt period (CSF Na+ concentration: 147.7 +/- 0.4 mmol/L vs 145.3 +/- 0.5 mmol/L; P less than 0.001). Levels of CSF pressure and potassium or calcium concentrations were not different between the two periods. Plasma NA and plasma renin activity (PRA) were lower and CSF NA levels tended to be lower in the high salt period. 3. The levels and the changes in sodium and NA in CSF were not significantly different between the salt-sensitive (n = 8) and the non-salt-sensitive (n = 7) subjects, but the changes in plasma NA and PRA were smaller in the salt-sensitive subjects. 4. These results indicate that the sympathetic nervous system is less suppressed in salt-sensitive subjects during high salt intake. This may be due to altered neural responsiveness to sodium loading rather than being greater increases in sodium concentration in the central nervous system.


Potassium channel activation improves blood flow pattern of conscious rats in cutaneous microcirculation.

1. A dose-dependent mean arterial blood pressure reduction (tailcuff method) to an intravenously administered potassium channel activator (22 or 24 micrograms/kg bw) was found in conscious rats. 2. Intravital microscopic analysis of skin microcirculation in conscious rats was performed with respect to erythrocyte flow velocity and diameters of capillaries. There was a dose-dependent increase of erythrocyte flow velocity; diameters of capillaries were dilated following a dosage of 6 and 12 micrograms/kg bw, but constricted following a dosage of 24 micrograms/kg bw. 3. Frequency distributions of velocity ranges in capillaries under observation (real time video recordings) proved that the increase of microvascular perfusion is manifested by a shift of maximal values to increasing velocity ranges. 4. It is concluded that potassium channel activation plays an important role in the local regulation of perfusion on the peripheral circulation.


Time course of regional flow distribution following reperfusion of the isolated ischaemic rat heart.

1. The regional distribution of flow was studied at different times after the onset of reperfusion in isolated rat heart preparations. The hearts were submitted to 30 min of global ischaemia followed by 60 min of reperfusion. Microspheres labelled with various nuclides were added to the perfusate before ischaemia and 1, 5, 20, and 60 min after the onset of reperfusion. 2. One minute after the start of reperfusion, the flow to the left ventricular inner layer was restricted to 0.5 +/- 0.2 mL/min per g (2-3% of the pre-ischaemic flow). In this segment, the perfusion remained at the same low level during the entire reperfusion period studied. At the onset of reperfusion the flow to the outer layer of the left ventricle was 4.8 +/- 1.7 mL/min per g (37% of the pre-ischaemic flow), and 3.0 +/- 1.3 mL/min per g (27% of the pre-ischaemic value) to the free wall of the right ventricle. The flow was progressively reduced in the outer layer of the left ventricle in the course of reperfusion. After 60 min of reperfusion the flow to the left ventricular outer layer was 2.5 +/- 0.9 mL/min per g (19% of pre-ischaemic flow when compared with the onset of reperfusion [P less than 0.05]). 3. It is concluded that a 'no-reflow' condition develops very early during reperfusion and becomes more marked during this period.


Isolation and characterization of the rat liver AVP receptor using [125I][d(CH2)5'sarcosine7]AVP.

1. A vasopressin (AVP) binding protein was purified from rat liver membranes by an improved method using [125I][d(CH2)5'Sarcosine7]AVP, a selective V1 AVP radioligand and a combination of CHAPS solubilization, gel filtration, lectin affinity and FPLC ion exchange chromatography. 2. The purified protein exhibited a maximum binding activity of 2480 pmol/mg protein with a KD of 4.5 nmol/L, which corresponds to a purification of approximately 26,700-fold. The molecular weight of this protein was 70,000 Da. 3. The binding of [125I][d(CH2)5'Sarcosine7]AVP to the solubilized membranes was dependent on the protein concentration, and was inhibited by the unlabelled peptides [d(CH2)5'Sarcosine7]AVP, AVP, and to a lesser degree by peptides with high V2 receptor affinity, such as 1-desamino-D-AVP and [d(CH2)5'D-Ileu2-Ileu4]AVP. 4. In addition, an AVP anti-idiotypic monoclonal antibody bound to both the partially purified and purified lectin affinity AVP binding protein in a concentration-dependent manner. These results indicate that the purified protein displays similar characteristics to the liver membrane-bound AVP V1 receptor.


Increased sensitivity to endothelin-1 in isolated Krebs'-perfused kidneys of streptozotocin-diabetic rats.

1. Vascular responses to endothelin-1 (ET-1) and noradrenaline (NA) were measured in isolated Krebs'-perfused kidneys of 2 week old streptozotocin-diabetic and non-diabetic rats. 2. Bolus injections of either ET-1 or NA caused dose-dependent increases in perfusion pressure. Responses to ET-1 (10-60 ng/g kidney), but not to NA (0.001-10 micrograms/g kidney), were significantly potentiated in kidneys of diabetic rats compared with non-diabetics. 3. Indomethacin significantly attenuated responses to NA (0.3-10 micrograms/g kidney) in kidneys of both diabetic and non-diabetic rats. 4. Neither indomethacin (1 mumol/L) nor the cyclo-oxygenase/lipoxygenase inhibitor BW755C (1 mumol/L) had any significant effect on the log dose-response curve to ET-1 in either group of kidneys. 5. Perfusion with N-nitro-L-arginine (NOLA; 10 mumol/L) had no effect on basal perfusion pressures, but potentiated responses to ET-1 in both groups of kidneys. However, the difference in responses to ET-1 between kidneys from diabetic and non-diabetic rats remained significant in the presence of NOLA. 6. ET-1 responses were inhibited in Ca(2+)-free Krebs' solution (plus 1 mmol/L EGTA). 7. The results of the present study indicate an increased sensitivity to ET-1 in isolated Krebs'-perfused kidneys of diabetic rats. Responses to ET-1 were unaffected by cyclo-oxygenase and/or lipoxygenase inhibitors, but were potentiated by an endothelium-derived relaxing factor (EDRF) synthesis inhibitor.


Measurement and identification of prorenin and renin in ovarian follicular fluid from cattle and pig.

1. In previous studies we have demonstrated and solved several methodological problems in relation to the measurement of prorenin by trypsin activation in rat, bovine, hog and horse plasma. 2. The aim of the present study was to develop a method for the measurement of prorenin in bovine and porcine ovarian follicular fluid. 3. Trypsin activation of follicular fluid generated angiotensin I immunoreactive material (AI IM) in both species. 4. The AI IM interfered with the renin assay, but could be completely removed by a cation exchange resin in a batch-wise technique. 5. The enzymatic activity of trypsin-activated prorenin and pre-existing active renin was completely inhibited by a specific inhibitor of renin. 6. The reactions were optimized and an accurate measurement of prorenin in ovarian follicular fluid was developed. 7. The existence of prorenin and renin in bovine ovarian follicular fluid was established. Prorenin and renin in porcine ovarian follicular fluid was demonstrated for the first time. 8. The ratio between ovarian follicular fluid and plasma was 43 for prorenin and 19 for active renin in cattle. The same ratios in pigs were 1.3 and 0.4, respectively. These findings indicate a species difference with respect to the amount of prorenin or active renin present in ovarian follicular fluid.


Hematologic parameters and iron stores in patients on hemodialysis for chronic renal failure.

Thirty-two patients on hemodialysis for chronic renal failure were investigated. A correlation was sought between bone marrow iron stores assessed on Prussian-blue stained smears, and some common hematological parameters such as red blood corpuscle indexes obtained by coulter counter, serum iron, iron-binding capacity and serum ferritin levels (measured by RIA). MCH and MCV were both found significantly depressed in patients with depleted iron stores, a situation not reflected by any of the other tested parameters. These results reveal a practical and simple guideline for the treating practitioner who wants to initiate iron supplementation or withdrawal in these patients especially in areas where more elaborate tests may not be at hand.


Primary hypothyroidism and multiple endocrine failure in association with hemochromatosis in a long-term hemodialysis patient.

A 56-year-old male patient on chronic hemodialysis developed liver cirrhosis. He received a total of 20 liters of blood transfusion. Bronze pigmentation of the skin and iron deposition to the liver, spleen, pancreas and thyroid gland, which was demonstrated by computed tomography and magnetic resonance imaging studies, and histological demonstration of iron deposition to the thyroid gland, bone marrow and gastric mucosa established a diagnosis of secondary hemochromatosis. Endocrine work-up revealed the presence of diabetes mellitus with minimum insulin secretory response, primary (or thyroprivic) hypothyroidism, hypoparathyroidism and hypogonadotropic hypogonadism. A wide-spread endocrine involvement as seen in this patient is a rare clinical feature of hemochromatosis secondary to massive blood transfusion in hemodialysis patients. Particularly, primary hypothyroidism due to iron deposition to the thyroid gland was quite a rare feature of hemochromatosis.


Clearance of 131I by hemodialysis.

There are no available data documenting the dialysis clearance of iodide in humans. This work quantitates the hemodialysis clearance of iodide (as 131I) over time and examines certain factors which influence that clearance. In a single-patient study, three dialysis periods were studied over the 24 to 96 hours following administration of 129 mCi 131I given as Na131I. Hemodialysis clearance of 131I was calculated both from the arterio-venous difference of 131I across the artificial kidney and the appearance of 131I in the expended dialysate. Calculations were based on 131I activity in whole blood, whole plasma, and the supernate of plasma treated with 10% trichloroacetic acid (TCA). The hemodialysis clearance of 131I was highest when calculated from the activity of the plasma supernate, 171.3 +/- 6.0 ml/min for the period 24-29 h. post dosing, and fell in a linear fashion with time. The clearance calculated from whole blood activity was always intermediate to that from whole plasma (lowest) or the plasma supernate (highest). The percentage of plasma 131I activity precipitated by TCA rose over the study period and displayed a strong negative correlation to the hemodialysis clearance of 131I. The hemodialysis clearance of iodide, as 131I, is on the order expected for a free ion and is 4-5 times higher than the endogenous renal clearance of the ion. However, the calculated clearance varies with respect to total time of dialysis and the fraction of blood in which the 131I activity is measured.(ABSTRACT TRUNCATED AT 250 WORDS)


IgA nephritis in HIV-positive patients: a new HIV-associated nephropathy?

Four HIV-positive patients were shown to have IgA-associated nephritis on biopsy, including one with anaphylactoid purpura. Three were homosexuals, while the fourth acquired the infection from his mother. All had hematuria, a variable degree of proteinuria and renal disease with a benign course. Serologic studies showed elevated levels of IgA as well as IgA immune complexes and rheumatoid factor. IgA antibodies to multiple HIV antigens were detected by Western blot. Pathologic studies showed tubuloreticular inclusions in endothelial cells and nuclear bodies in interstitial cells in all cases. HIV antigens were not detected in kidney biopsies by monoclonal antibodies nor was HIV viral genome demonstrated by in situ hybridization. The possibility that this represents a unique type of IgA-associated HIV nephropathy is discussed.


Incidence of microalbuminuria in ambulatory patients with acquired immunodeficiency syndrome.

Nephropathies associated with human immunodeficiency syndrome (HIVAN) are characterized by gross proteinuria, lack of change in blood pressure, and various histologic lesions. The present study prospectively measured microalbuminuria in 72 HIV-seropositive patients (3 asymptomatic, 32 AIDS-related complex, 37 AIDS) screened for Phase I clinical pharmacology studies. There were 14 patients (19.4%) that had abnormal urinary levels of microalbumin; 7 of these patients (50%) had proteinuria similar to those values found in diabetic nephrotic syndrome. Microalbumin levels were not correlated with race, sex, risk factors of AIDS, disease history, or concurrent drug therapy. In contrast, urinary microalbumin levels were correlated with CD 4 T-cell and WBC counts, tumor necrosis factor alpha and beta 2-microglobulin levels, suggesting an association between AIDS progression and microalbuminuria. By monitoring urinary microalbumin levels, those patients susceptible to the development of nephrotic syndrome could be identified and prophylactic measures initiated.


Two-color analysis of lymphocyte subpopulations in patients with nephrotic syndrome due to membranous nephropathy.

Two-color flow cytometry was carried out to determine the correlation between cell-mediated immunity and the levels of proteinuria in 30 patients with membranous nephropathy. Lymphocyte subpopulations were measured by two-color flow cytometry using various monoclonal antibodies of the Leu series. Clinically, the patients were divided into four stages as follows: 1. untreated nephrotic stage, 2. prednisolone (PSL) treated nephrotic stage, 3. persistent proteinuric stage (incomplete remission, ICR) and 4. complete remission (CR). Two-color flow cytometry showed a significant decrease in Leu 2a+15+ (suppressor T) cells and relative increase in Leu 3a+8+ (suppressor inducer T) cells in the untreated nephrotic stage. The mean Leu 3a+8-/Leu 2a+15+ (helper/suppressor) cell ratio was normalized in the persistent proteinuric stage or complete remission after treatment with PSL. Patients with membranous nephropathy showed a significant elevation of Leu 2a+DR+ cells after treatment with PSL. The abnormalities of suppressor T cells and suppressor inducer T cells in the peripheral blood appear to reflect the levels of proteinuria in patients with membranous nephropathy. It was concluded that PSL might stimulate Leu 2a positive cells and then increase the number of Leu 2a+15+ cells in the peripheral blood of patients with membranous nephropathy.


Chronic dialysis in patients with systemic amyloidosis: the experience in northern Italy.

The clinical outcome of 61 patients with renal amyloidosis treated with chronic dialysis was reviewed. Eighteen patients, 4 with primary or AL amyloidosis and 14 with reactive or AA amyloidosis, died within one month from starting treatment. The other 43 patients were treated with dialysis for 3 to 199 months and are the object of this study. Sixteen patients had AL amyloidosis and 27 had AA amyloidosis. Thirty-five patients were treated with hemodialysis (HD) for a mean period of 40 +/- 47 months and 8 were treated with continuous ambulatory peritoneal dialysis (CAPD) for 20 +/- 15 months. Patient survival rate at 1 and 5 years was 68% and 30% respectively. There was no difference in survival rate between patients treated with HD and those treated with CAPD, while patients younger than 45 had a better 5-year survival rate. Twenty four (60%) patients achieved a satisfactory rehabilitation with dialysis. At the last follow-up, 15 patients (14 on HD, 1 on CAPD) were alive 61 +/- 58 months after starting dialysis. Twenty-eight patients died after 30 +/- 20 months. The main causes of death were: cardiovascular accident (11), stroke (3), sepsis (5) and cachexia (5). The most important extra-renal complications of amyloidosis were related to cardiovascular involvement (heart failures, arrhythmias, hypotension) and gastrointestinal involvement (malabsorption). Intra-dialytic hypotension in patients on HD and peritonitis in patients on CAPD were the main problems related to dialytic procedure. his study confirms that life expectancy and the quality of life of dialysis patients with systemic amyloidosis are poorer than those of general dialysis population.(ABSTRACT TRUNCATED AT 250 WORDS)


Heparin-induced thrombocytopenia in renal failure.

A 35-year-old patient with symptomatic chronic renal failure secondary to hereditary nephritis underwent heparinization during urgent hemodialysis. Subclavian catheter insertion was complicated by staphylococcal septicemia which precluded Gore-tex graft placement. Arteriovenous fistula failed immediately postoperatively and thrombectomy was required. Heparin-induced thrombocytopenia was suspected and the test was strongly positive. Acetyl salicylic acid (ASA) 40 mg, was used with heparin for dialysis, and there were no episodes of gastrointestinal hemorrhage or access site thrombosis. The use of very low-dose ASA in this setting is reported.


Serum and urinary ceruloplasmin in experimental nephrotic syndrome.

The levels of ceruloplasmin (Cp) and total protein were measured in serum and urine from rats with experimental nephrotic syndrome (NS) for 20 days after a single injection of puromycin aminonucleoside (PAN). Control values for Cp in serum and urine were: 0.23 +/- 0.01 mg/ml and 0.063 mg/day, and those for total protein were: 7.1 +/- 0.14 g/dl and 2.1 +/- 0.6 mg/day, respectively. It was found that: a) serum Cp decreased on day 6, remained low until day 10 (0.07 +/- 0.01 to 0.08 +/- 0.01 mg/ml), and returned to control levels on day 12; b) total serum protein decreased on day 4, reached the lowest value on day 6 (3.3 +/- 0.3 g/dl) and returned to control levels on day 16; c) Cp in urine increased on day 6, reached a peak value on day 8 (0.62 +/- 0.07 mg/day), then decreased but remained high on day 20; and d) total protein in urine increased on day 5, reached a peak value on day 10 (692 +/- 59 mg/day) and returned to control values on day 20. There was a close association between the levels of Cp and total protein in serum and urine. The decrease of circulating Cp indicates that a typical acute phase response does not occur in the PAN-nephrotic rats. The loss of Cp in the urine of the nephrotic rats may contribute to the decrease in the serum levels of this protein.


The effect of cigarette smoking on lymphocyte subsets and progression to AIDS in a cohort of homosexual men.

We investigated the effect of cigarette smoking on the percentage of CD4 and CD8 cells (CD4%, CD8%) within a prospective study of homosexual men in Vancouver, Canada and compared progression rates to AIDS among seroincident smokers and non-smokers. Serial measurements of CD4% and CD8% obtained from four annual visits were available for 299 men and were compared with respect to smoking status and serologic group. CD4% was significantly elevated (p less than 0.025) and CD8% was significantly lower (p less than 0.002) in seronegative smokers compared to non-smokers. However, no effect of smoking was observed in the seropositive group for either of these variables. In a prospective analysis of 122 seroincident subjects, we failed to find a significant association between smoking and progression to AIDS (p = 0.829) or Pneumocystis carinii pneumonia (p = 0.894). At 72 months, cumulative AIDS progression was 29.1% in seroincident smokers compared to 25.2% in seroincident non-smokers. These data suggest that in the absence of HIV, smoking is associated with higher CD4% and lower CD8% but these effects are not present in seropositive subjects with longer durations of infection. Cigarette smoking does not appear to be associated with an altered rate of progression to AIDS.


The clinical utility of serum lactate dehydrogenase in diagnosing pneumocystis carinii pneumonia among hospitalized AIDS patients.

It has been previously demonstrated that serum lactate dehydrogenase is elevated among HIV patients with pneumocystis carinii pneumonia (PCP). To evaluate the clinical utility of this test we analyzed the admission LDH levels of patients hospitalized for the first time due to the secondary complications of AIDS. Among 76 patients without a prior history of PCP, 41 (54%) had PCP diagnosed during their hospitalization while 35 (46%) did not have PCP. Serum LDH was significantly higher among PCP patients than in patients without PCP (mean = 423 IU/L vs 234 IU/L). Receiver operating characteristic curve analysis demonstrated that at an optimal cutoff point of LDH greater than or equal to 240 IU/L, the test sensitivity and specificity were 0.78 and 0.74 respectively among all hospitalized patients. However, when only patients with dyspnea were considered, the optimal test sensitivity and specificity improved to 0.94 and 0.78 at a cutoff point of LDH greater than or equal to 220 IU/L. Comparing the areas under fitted ROC curves, serum LDH was a significantly better discriminator among patients with dyspnea than among those who were not short of breath. We conclude that while serum LDH is strongly associated with the presence of PCP among AIDS patients, it is a poor screening test for PCP when applied to all hospitalized AIDS patients with and without respiratory complaints. Serum LDH is no substitute for appropriate microbiological studies. However, with further evaluation, it may prove to be a useful test in guiding the clinical management of dyspneic patients in whom sputum or bronchial examinations are negative or not immediately available.


A new bioactive molecule for improving vascular graft patency: exploratory trials in dogs.

Myxalin is a new bioactive molecule that we have isolated from the culture medium of Myxococcus xanthus, a non-pathogenic Gram negative bacterium. This glycopeptide possesses an antithrombotic effect in vivo and has been shown to promote human endothelial cell growth in vitro. With the object of exploring its ability to improve vascular graft healing and patency, myxalin was immobilized on 6 mm diameter knitted polyester prostheses using gelatin as a carrier, and the prosthesis was then implanted as an infrarenal abdominal arterial substitute in dogs for a period of 2 weeks. Two additional series of implantations were conducted for control purposes: one with gelatin-coated prostheses without myxalin, the other following normal preclotting of the polyester grafts. In order to select adequate sterilization conditions which can preserve the biological activity of myxalin, the prostheses were sterilized according to 3 different sterilization processes (gamma radiation and ethylene oxide either at 63 degrees C or 37 degrees C). At the sacrifice, all grafts were patent. The myxalin treated prostheses exhibited improved blood compatibility in terms of fewer thrombotic deposits and significant inhibition of platelet and fibrinogen uptake on their luminal surfaces. In addition, the development of a thin collagenous internal capsule with endothelial cells secreting high levels of prostacyclin was observed at both anastomoses of the myxalin-treated grafts sterilized by gamma radiation.


How many persons in Canada have been infected with human immunodeficiency virus? An exploration using backcalculation methods.

We have used the technique of backcalculation to estimate the number of persons in Canada who have been infected with human immunodeficiency virus type 1 (HIV) as of July 1989. We first corrected national AIDS surveillance data in Canada for reporting delay and for underreporting. We then used standard Weibull natural history models as well as an alternative progression model in which the hazard of AIDS was dampened in keeping with observed data from large cohorts. Maximum likelihood techniques were then used to derive the infection curve most consistent with these data. Our best estimate based on this alternative progression model, an underreporting rate of 20%, and a logistic infection curve, was that approximately 29,000 persons in Canada had ever had HIV infection as of July 1989. In a sensitivity analysis utilizing less likely assumptions, the estimates ranged from 17,243 to 48,277. Restricting the same backcalculation process to females under the same assumptions, we estimated that approximately 2,900 females in Canada had ever had HIV infection as of July 1989. The best fitting step function infection curve in females appears to be continuing to rise. Given these estimates, it follows that approximately one in ten infected persons in Canada is female. However, females have only accounted for about one in seventeen AIDS cases. These data are in accord with the widespread impression that transmission of HIV to women has occurred more recently and is on the rise across Canada. The current estimate is lower than previous estimates which placed the number of infected Canadians in the 50,000 to 100,000 range. This lowering should not be taken to mean the situation is improving; rather, the early estimates were simply too high having been based on inadequate data and a rudimentary understanding of the natural history of HIV. Backcalculation is an excellent technique for modelling the incidence of HIV infection several years in the past, but it is not reliable for the most recent few years. A significant increase in HIV infection rates may have occurred in the past few years and it would be beyond the capacity of backcalculation to detect. Backcalculation and unlinked cross-sectional specimen surveys together have the potential to provide an effective means of monitoring the HIV epidemic.


Seminal plasma gamma-aminobutyric acid (GABA) levels in normospermic men.

Serum and seminal gamma aminobutyric (GABA) concentrations were documented in 10 healthy volunteers. Mean (+/- S.E.M.) GABA concentrations were 0.39 +/- 0.03 microM in serum and 103.3 +/- 28.2 microM in seminal fluid. These differences are in keeping with data reported for the rat and rabbit. A regulatory role for GABA in the reproductive tract is postulated.


High protein diet complements resin therapy of familial hypercholesterolemia.

The intermediate-term effects on plasma lipoprotein lipids of substituting meat and dairy protein for carbohydrate in the diets of five subjects (three women, two men) with familial hypercholesterolemia receiving cholestyramine (mean dose, 18 g/d) were studied. Subjects were randomly allocated to either the high or low protein diets (mean 27 versus 10% of energy as protein, 25% as fat, and 48 versus 65% as carbohydrate) for 4 to 5 weeks and then switched to the other diet for another 4 to 5 weeks. Mean fasting plasma HDL cholesterol rose significantly by 17 +/- 3% (1.11 +/- 0.12 vs 0.95 +/- 0.11 mmol/L, p less than 0.005, n = 5), whereas total triglycerides fell by 23 +/- 2% (1.7 +/- 0.3 vs 2.2 +/- 0.3 mmol/L, p less than 0.005, n = 5), VLDL triglycerides fell by 28 +/- 5% (0.88 +/- 0.15 vs 1.18 +/- 0.19 mmol/L, p less than 0.02, n = 5), VLDL cholesterol fell by 32 +/- 7% (0.39 +/- 0.08 vs 0.56 +/- 0.09 mmol/L, p less than 0.01, n = 5), the ratio of LDL cholesterol: HDL cholesterol by 19 +/- 5% (4.7 +/- 0.7 vs 5.7 +/- 0.7, p less than 0.05) and that of total cholesterol: HDL cholesterol by 16 +/- 5% (6.6 +/- 0.5 vs 8.0 +/- 0.7, p less than 0.05) on the high versus low protein diet. Increasing dietary protein intake at the expense of carbohydrate may be useful in treating hypoalphalipoproteinemia and/or hypertriglyceridemia in patients with familial hypercholesterolemia.


Hyperresponsiveness of sympathoadrenal system in conscious DOCA-NaCl and SHR rats in response to acute hemorrhagic hypotension.

The sympathoadrenal basal tone and reactivity were evaluated by the measure of plasma norepinephrine (NE) and epinephrine (EPI) levels in chronically cannulated awake and unrestrained animals under basal conditions and following an acute withdrawal of blood volume necessary to decrease the mean arterial pressure (MAP) by 50 mmHg in normotensive, in deoxycorticosterone acetate (DOCA) and salt (NaCl) hypertensive and in spontaneously hypertensive (SHR) (10-11 weeks) rats. In DOCA-NaCl and SHR rats the basal sympathoadrenal tone was found to be increased as was reflected by the higher plasma levels of both catecholamines. Moreover, an enhanced reactivity of the sympathoadrenal system was also observed in DOCA-NaCl hypertensive rats as well as a slight sympathetic hyperreactivity in SHR in response to the hemorrhagic hypotension suggesting the possibility of alterations in the baroreflex functions or in the local modulatory mechanisms. In addition, the acute hemorrhagic hypotension triggered compensatory mechanisms which permitted a rapid return of the MAP to the baseline values in normotensive rats and in the SHR. However, in DOCA-NaCl hypertensive rats, the return of the MAP was delayed and remained below initial levels even 60 min after the hemorrhagic hypotension, suggesting a less efficient compensatory mechanism in these animals despite a markedly potentiated sympathoadrenal response. To explain such a discrepancy, it may be hypothesized that the potentiated sympathoadrenal reactivity could induce a decrease in vascular reactivity by an acute desensitization of the vascular alpha-adrenoceptors in DOCA-NaCl hypertensive rats.


Psoriatic spondyloarthropathy in men and women: a clinical, radiographic, and HLA study.

Psoriatic spondyloarthropathy as defined by the presence of inflammatory back pain and stiffness, sacroiliitis on physical examination, radiographic evidence of grade greater than or equal to 2 sacroiliitis, and classical or paramarginal syndesmophytes on spinal radiographs was identified in 82 women and 112 men followed at the Psoriatic Arthritis Clinic according to a standard protocol. A logistic regression analysis was performed to look for variables which discriminate between men and women with this condition. No differences in type of peripheral arthritis, degree of damage, or medication were noted between the two groups. However, there was some evidence for more advanced spondyloarthropathy in men. There were no differences in the frequency of HLA B27 or any of the psoriatic arthritis-related HLA antigens. Thus, there may be gender-related differences in the expression of psoriatic spondyloarthropathy, which are unrelated to HLA antigens.


Newborn screening for sickle cell and other hemoglobinopathies: a Canadian pilot study.

We estimated incidence of HbS disease in Quebec. It is approximately 9 cases per 100,000 births (equivalent to the incidence of the hyperphenylalanemias). Accordingly, we performed a voluntary pilot study in 9 self-identified ethnic groups; 3528 families were counselled about the relevance of newborn screening for hemoglobinopathies; and 2779 cord blood samples were collected (participation rate, 78.7%) and analyzed for Hemoglobin S and other hemoglobin variants by cellulose acetate electrophoresis. There were 95 (3.42%) positive tests on the initial (cord blood) samples, of which only 40 could be confirmed because of low participation in follow-up. We identified 8 false-positive tests; 7 had been classified initially as alpha-thalassemia trait and one as HbC heterozygosity on the first test. The relative frequency of hemoglobinopathy genes (confirmed) was: 52.5% HbS; 22.5% alpha-thalassemia; 22.5% other mutation; all but one patient with sickle cell disease were heterozygotes; the majority (71%) of HbS genes were accounted for by the 7% of screened newborns who were Black; a further 24% of the HbS genes were accounted for by 7% with Central American ancestry. Record linkage of the findings in heterozygotes for use later in life is an unsolved problem. Seventy five first-degree relatives of the 48 probands were screened in follow-up studies (64% of parents participated); 5 couples at risk for having a future child with a hemoglobinopathy were identified. Attitudes toward follow-up varied among the ethnic groups. The single family with an affected newborn (sickle cell anemia) was counselled effectively; the infant received penicillin prophylaxis.(ABSTRACT TRUNCATED AT 250 WORDS)


Pregnancy outcome and infant development following gestational cocaine use by social cocaine users in Toronto, Canada.

To determine the effect of first trimester cocaine use on pregnancy outcome we conducted a prospective cohort study of 30 women admitting to social cocaine use (SCU) during early pregnancy, 20 users of cannabis during the first trimester and 30 matched recreational drug-free control subjects. The groups were of similar age, marital status, and obstetric history and were predominantly white. They were of similar socioeconomic status (SES), however the spouses of the cocaine users were of significantly lower SES than those of both control groups (p less than 0.005). The number of years of education of the cocaine users and the fathers of the SCU-exposed fetuses was significantly lower than that of the recreational drug-free control subjects (p = 0.004), however, female IQ was similar among the three groups (109.1 +/- 12.4 cocaine; 109.1 +/- 25.2 cannabis; 114.1 +/- 11.7 drug-free). Alcohol and cigarette use was greater among the cocaine users than among subjects of the recreational drug-free control group (p less than 0.025). Cocaine and the associated lifestyle were not associated with any adverse obstetric or neonatal endpoint (pregnancy weight gain, incidence of delivery complications, gestational age, birth weight, Apgar scores, and rates of major and minor malformations). There were no differences between groups in attaining developmental milestones. Mental and motor scores on the Bayley Scales of Infant Development and Vineland Adaptive Behavior Scales were identical among the three groups, studied at a mean of 19.7 months of age. We conclude that outcome of pregnancy of social cocaine users and subsequent infant physical and cognitive development are within normal limits at 1.6 years of age.


Methionine auxotrophy in inborn errors of cobalamin metabolism.

Several of the inborn errors of vitamin B12 (cobalamin, Cbl) metabolism (cblC, cblD, cblE, cblF, cblG) are associated with homocystinuria and hypomethioninemia due to a functional deficiency of the cytoplasmic enzyme methionine synthase which requires methylcobalamin (MeCbl) as a cofactor. We compared the growth of cultured fibroblasts from controls, from patients with a selective deficiency of MeCbl (cblE and cblG), with those with a defect in both MeCbl and adenosylcobalamin (AdoCbl) (cblC, cblD and cblF), in methionine and folic acid-free media to their growth in fully supplemented medium. Control cells were able to grow in deficient medium supplied with homocysteine, cobalamin and folate, while mutant cells were not, due to their inability to synthesize methionine from its immediate metabolic precursor, homocysteine. This differential growth is useful in screening for genetic defects of methionine biosynthesis.


Biocompatibility of surgical-grade dense polycrystalline alumina.

This article reviews the knowledge about biocompatibility of alumina since its introduction as a material for use in joint replacements. Alumina is a hydrophilic material with high wettability allowing very low friction with negligible wear. Macrophages loaded with alumina particles show no morphologic alteration and do not lose their chemotactic ability. The host response has been studied for bulk and particulate alumina in soft tissues, as well as in human and animal bone under loaded and nonloaded conditions. The soft-tissue response to bulk alumina exhibits minimal fibrosis, and direct bone contact is achieved at compression-loaded interfaces. Examination of human biopsies from failed total hip prostheses reveals a foreign-body reaction containing predominantly macrophages loaded with alumina particles. No lymphocyte or plasma-cell infiltration is observed because of the absence of soluble component release. The amount of necrosis and fibrosis was lower than that associated with metal or polyethylene debris. In summary, alumina exhibits greater bioinertness than all other implant materials currently available for joint replacement.


Combination treatment for adhesive capsulitis of the shoulder.

Twenty-two patients (23 shoulders) with arthrographically verified adhesive capsulitis of the glenohumeral joint were treated by a combination of distention-arthrography, local anesthetics and steroids intraarticularly, and manipulation. The mean duration of the disease at the time of treatment was 14 months, and all patients suffered from disabling pain and stiffness. A rapid improvement was seen after treatment and at four to six weeks: 91% (21/23) of the patients had no or slight pain and 83% (19/23) of the patients had normal, or almost normal, range of motion. The treatment was well tolerated and no complications were recorded. The combination treatment for adhesive capsulitis of the shoulder is safe, yields immediate results, and is cost effective.


Ultrasonography of rotator cuff tears.

This is a prospective study of ultrasonography of the rotator cuff mechanism as an alternative to arthrography for screening rotator cuff tears. Seventy-two patients (40 men and 32 women) with possible rotator cuff tears were referred for shoulder arthrography. Before arthrography, bilateral shoulder sonography was performed by a technician under the direction of a radiologist. Arthrograms and sonograms were read separately, and a decision as to the absence or presence of a rotator cuff tear was made without knowledge of the results of the other examination. The results showed 90% sensitivity and 91% specificity, with a positive accuracy of 87%, and a negative accuracy of 93%. Ultrasonography of the rotator cuff is a noninvasive, painless, and cost-effective screening method for patients with a suspected rotator cuff tear.


Acetabular reconstruction with a threaded prosthesis for failed total hip arthroplasty.

The MEC-Ring threaded acetabular component was used in 35 patients for revision of failed cemented hip arthroplasties, and 32 have been observed for two to four years (mean, 2.5 years). With only a short-term follow-up period, 44% of patients have already required revision for failure of the MEC-Ring acetabular component. Patients with especially poor acetabular bone stock that had had structural bone graft had a significantly higher rate of failure. The authors developed a technique of supine oblique roentgenograms that allowed better visualization of the component-bone interface. Eighty-six percent of patients had radiolucencies, and 67% of these were progressive. The presence of progressive radiolucencies, component migration, or both was associated with a higher failure rate. Progressive radiolucencies were also associated with a worse pain score in patients whose arthroplasties have not failed. The MEC-Ring threaded component is not recommended for revision hip arthroplasty, especially in cases with poor acetabular bone stock.


A comparison of total hip arthroplasty and hemiarthroplasty for treatment of acute fracture of the femoral neck.

One hundred sixty-six acute, nonpathologic displaced femoral neck fractures in elderly patients were treated with either unipolar hemiarthroplasty (122 operations; 77 cemented, 45 uncemented) or total hip arthroplasty (THA) (44 operations; all cemented). The average age, (75.2 years of age in the THA group 76.2 years of age in the hemiarthroplasty group), anesthesia risk classification, in-hospital mortality, early complications, and dislocation rates were comparable in each treatment group. In an average long-term follow-up period of 56 months, pain, walking, and function scores were higher with THA than with cemented or uncemented hemiarthroplasty. Revision rates were 2.2% after THA, versus 7.9% for cemented hemiarthroplasty and 13% for uncemented hemiarthroplasty. Hemiarthroplasty is recommended for the older patient, who may be occasionally active outside of the household. The healthy, active patient, however, may benefit from THA rather than hemiarthroplasty.


Evaluation of the learning curve associated with uncemented primary porous-coated anatomic total hip arthroplasty.

The results of the first and second groups of 50 consecutive primary, uncemented porous-coated anatomic arthroplasties were analyzed to evaluate the learning curve associated with the procedure. Femoral fit, acetabular cup angle, femoral fracture rate, minimum two-year clinical hip ratings, and clinical symptoms were compared between the two groups. Significant improvement in achieving better femoral canal filling with the prosthesis and lower acetabular cup angle placements was documented in the second 50 cases. Although a definite learning curve in mastering the technique of uncemented total hip arthroplasty was observed, thigh pain rate and clinical ratings were not improved after two years.


Heterotopic bone in hip arthroplasties. Cemented versus noncemented.

Sixty-six hip arthroplasties in 55 patients were reviewed to specifically study cemented versus noncemented procedures, as related to heterotopic bone formation (HBF). Other factors considered included the type of arthroplasty, surgical approaches, preoperative and postoperative medicines, preoperative predisposing diagnoses, range of motion, and pain. The overall percentage of heterotopic ossification was 64%. There was no significant difference between cemented (67%) and noncemented (55%) procedures. Except for an increased percentage (80%) of ossification after a trochanteric osteotomy, there were no significant differences between the three reviewed surgical approaches. Male osteoarthritics had the highest overall HBF. Eighty percent of patients who previously had developed HBF also did so with a contralateral hip surgery. Surprisingly, all patients with gout (100%) developed HBF. Acetylsalicylic acid used prophylactically for anticoagulation had no significant effect. Resurfacing arthroplasty procedures accounted for half of the severe grades of HBF. A decreased range of motion occurred with more severe grades of HBF.


Intrapelvic extraction of a total hip prosthesis. A case report.

A 69-year-old man with a total hip prosthesis, recurrent infection, and intrapelvic incarceration of the acetabular components required extraction of a long-stem total hip prosthesis through three incisions. Retroperitoneal intrapelvic extraction of the incarcerated prosthesis was necessary. This approach allowed removal of intrapelvically migrated components and the eradication of the infection. The patient had no signs of infection five years postoperatively.


Pulmonary embolism in total hip and knee arthroplasty. Risk factors in patients on warfarin prophylaxis and analysis of the prothrombin time as an indicator of warfarin's prophylactic effect.

This study was designed to identify those total arthroplasty patients at high risk for embolism even while on a proven warfarin prophylactic regimen and to identify the measure of anticoagulation that would be most efficacious in the prevention of pulmonary embolism (PE). A series of 2348 total arthroplasty patients had a preoperative perfusion scan and a postoperative ventilation/perfusion scan. All patients were placed on a low-dose warfarin protocol. Eighty-one patients were identified as having a PE by pulmonary arteriography (incidence of 3.4%). Of these, 89% were asymptomatic and no case was fatal. A control group of 159 patients without PE was used for comparison. Patients older than 65 years of age with a history of genitourinary infection were identified as being at higher risk of PE while on a proven warfarin prophylactic program. These patients may need additional prophylactic measures to reduce the risk of PE. In contrast, patients with a history of phlebitis, PE, obesity, or varicosities were not at excess risk for PE while on warfarin prophylaxis; therefore, no additional prophylactic measures are required. All prothrombin time profiles were within the prophylactic range. Therefore, the actual prothrombin time may not be the critical determinant of the level of anticoagulation or prophylaxis achieved.


Separation of the polyethylene liner from acetabular cup metal backing. A report of three cases.

In three young patients with cementless Porous Coated Anatomic (PCA) total hip prostheses implanted two to four years previously, the polyethylene liner separated from metal backing. These cups were of the original PCA design, manufactured and packaged as single assembled components, rather than the more recent two-piece components packaged with interchangeable liners separate from the metal backing. Each case of separation was associated with the failure of the thin outer polyethylene rim and central polyethylene peg on the back of the liner that secures it to the metal backing. Cup liners should be securely attached to the metal backing. The possibility of polyethylene failure is considerable when cementless metal-backed acetabular cups are used in active young patients.


The modified Insall-Salvati ratio for assessment of patellar height.

The Insall-Salvati ratio for the assessment of patellar height was the first widely used index to be relatively independent of knee flexion. Despite the subsequent publication of other indices, it remains the most widely used index. The Insall-Salvati ratio nevertheless has drawbacks, one of which has received little attention: the ratio lacks sensitivity to patellar morphology. Unusual patellar shapes can lead to misleading values of the Install-Salvati ratio. In particular, the authors have found a significant number of inaccurate readings for patellar height in patients whose patella exhibits a long distal (nonarticulating) facet. A modified Insall-Salvati ratio is described which, when applied in conjunction with the traditional ratio, significantly reduces these errors. The cutoff point between normal and alta for this modified Insall-Salvati ratio is 2. One half of the cases of patella alta in this study were missed by the traditional ratio, yet identified by the modified index.


A prospective and blinded investigation of magnetic resonance imaging of the knee. Abnormal findings in asymptomatic subjects.

To evaluate magnetic resonance imaging (MRI) of meniscal, ligamentous, and bony abnormalities in patients without clinical symptoms, scans were performed on 74 asymptomatic volunteers without histories or symptoms of knee injury. Before review by three radiologists in an independent and blinded fashion, the scans were mixed with 26 MRI scans from symptomatic patients. Sixteen percent of the asymptomatic volunteers had meniscal abnormalities consistent with a tear. The prevalence of MRI findings of a meniscal tear increased from 13% in individuals younger than 45 years of age to 36% in those older than 45. An additional 30% of the volunteers showed meniscal abnormalities consisting of a linear area of increased MR signal not communicating with a meniscal edge, which was not interpreted to represent a tear. The high incidence of abnormal MRI findings in asymptomatic subjects underscores the danger of relying on a diagnostic test without careful correlation with clinical signs and symptoms. These findings also emphasize the importance of access to relevant clinical data when interpreting MRI scans of the knee.


A ten- to 15-year follow-up observation of high tibial osteotomy in medial compartment osteoarthrosis.

High tibial osteotomy (HTO) was performed on 86 medially osteoarthritic knees in 78 patients. Twelve patients died during the follow-up period. Fifty-six knees of 51 patients were evaluated twice postoperatively: once at six years after surgery and again after ten to 15 years. Results were satisfactory in 88% of the knees at the six-year follow-up evaluation and in 63% at the post-ten-year follow-up evaluation. Ten-year follow-up results significantly deteriorated. The femorotibial angle (FTA) at the time of bone union after HTO was a significant factor that contributed to the ten-year results. In patients maintaining excellent improvement of knee function at the post-ten-year follow-up evaluation, the mean FTA at one year after surgery was 165 degrees; this value was constant through ten years after HTO. An FTA of 164 degrees-168 degrees should be attained to ensure favorable long-term results in HTO.


Role of ceramic implants. Design and clinical success with total hip prosthetic ceramic-to-ceramic bearings.

Ceramic implants have become of great interest because of the increased awareness that wear debris from metal-polyethylene components of total hip prostheses can cause osteolysis around implants. Polyethylene wear rates with the Charnley total hip prosthesis were found to be from 0.1 to 0.2 mm/year in the elderly, which corresponded to 30 to 80 mm3 of polyethylene debris being released to the joint tissues. This in turn can be related to 40 million to 40 billion particles being released into the joint every year. This polyethylene particulate is heavily implicated in the osteolytic destruction of periarticular tissues. The ceramic ball, ceramic cup combination of total hip prostheses may have promise of wear rates that could be thousands of times smaller than polyethylene alone. Such alumina ceramic prosthetic concepts were introduced in Europe from 1970 to 1973. Under Food and Drug Administration regulations at that time, the only U.S. introductions allowed circa 1980 were the Autophor and Xenophor types of ceramic prostheses. However, this particular prosthetic design was not successful in the United States because of pain, neck-socket impingement, ceramic fracture, and component loosening. This did not therefore appear to be a successful compromise in the hands of U.S. surgeons. Ceramic innovations from Europe now include cemented ceramic cups of "matching" tolerances with the femoral ball, and press-fit Ti-alloy acetabular shells with modular ceramic inserts. In addition, alumina and zirconia ceramic balls are now in routine clinical use in Europe. The objectives of this Symposium are to highlight these ceramic ball, ceramic cup innovations with their long-term clinical results from Europe. Then one can evaluate which of these innovations in material and design selections offers the best possible alternatives in the 1990s.


Clinical versus instrumented knee testing on autopsy specimens.

The accuracy, reliability, and reproducibility of the Genucom Knee Analysis System and Knee Signature System (KSS) for anteroposterior knee laxity evaluations were compared. The devices detected the same relative change in laxity between normal and anterior cruciate ligament-deficient specimens during Lachman and drawer testing; however, the absolute values differed. In a clinical study, two examiners performed three independent Lachman and drawer tests using the Genucom, KSS, and a subjective clinical examination on ten patients. The Genucom demonstrated interexaminer differences during the Lachman test. The clinical examination proved to be more reliable than either instrumented device for both Lachman and drawer testing. The intraexaminer variability of the Genucom and KSS was large, with the average 95% confidence limits about the mean for the Genucom and KSS equal to +/- 4.2 and +/- 2.8 mm, respectively. These findings question the accuracy, reliability, and reproducibility of the instrumented methods.


Long-term results of surgical management of Achilles tendinitis in runners.

Achilles tendinitis is a common occurrence in long-distance runners. Although most respond well to conservative therapy, there are some who require operative intervention. The short-term results of surgical treatment are good, with a success rate more than 85%. The authors present nine successful long-term results in runners. However, in two of the runners who continued to compete and train at long distances, symptoms recurred. Reoperations were performed to permit successful running careers for five and nine years. Runners resumed their careers after the second operation by supervised training and long-distance, competitive activities.


Surgical correction of foot deformities after stroke.

Of 104 patients with corrective surgery for foot deformities subsequent to a cerebrovascular accident from 1980 until 1983, 53 patients returned for clinical examination and 22 patients were evaluated by questionnaire and telephone interview. The average follow-up period was 6.4 years. The operative techniques were tenotomy of the toe flexors for hammer-toe deformity, lengthening of the aponeurosis of the gastrocnemius for equinus deformity, and transfer of the anterior tibial tendon or the posterior tibial tendon or the long toe flexors for varus deformity. In 74% of patients, correction was maintained; 79% did not use an orthosis; 51% could bathe unassisted; and 76% were satisfied with the results. The ability to walk was related to the degree of paralysis, the age of the patient at surgery, and the walking speed at discharge.


Ipsilateral fractures of the distal radius and scaphoid treated by Herbert screw and external skeletal fixation. A report of two cases.

Two patients with comminuted, displaced fractures of the distal radius associated with ipsilateral, undisplaced scaphoid fractures were treated by internal fixation of the scaphoid fracture with a Herbert screw in association with external fixation of the distal radial fracture. One of the patients had a limited open reduction of the distal radius combined with bone grafting. Both patients had satisfactory results. Internal fixation of the scaphoid is indicated if distraction is applied to the carpus to treat an associated fracture of the distal radius, even if the scaphoid fracture is undisplaced.


Neurologic deficits in major pelvic injuries.

Nerve injury is a common complication of major pelvic injuries. Of 73 patients examined who suffered major pelvic injuries, 24 (33%) had resultant neurologic deficits. The extent of nerve injury is proportionate to the severity of the posterior pelvic bone injury. Sacroiliac dislocation and sacral fractures may be equally complicated by nerve injury. This study suggests that nerve recovery starts three months after injury and stops after two years. Complete recovery was not recorded in severe nerve injuries. Eighty percent of patients recovered from impotence. Nerve injury was found to affect the functional outcome of patients with pelvic injuries. For these reasons, injury should be considered and looked for in every case of pelvic injury.


Open reduction of acetabular fracture in pregnancy. A case report.

A 24-year-old woman in her 20th week of pregnancy sustained a severely displaced acetabular fracture. Skeletal traction failed to achieve reduction. Open reduction and internal fixation were performed through an extended iliofemoral approach without affecting the pregnancy. At full term, she had a normal delivery. Four years after the injury, the patient had a pain-free hip with full range of motion and a healthy child. The potential benefit or danger of surgery to the patient and her pregnancy was thoroughly considered.


Segmental transport after unreamed intramedullary nailing. Preliminary report of a "Monorail" system.

The Ilizarov method of segmental bone transport has been shown to be an alternative to more conventional treatments of posttraumatic bony defects. After extensive clinical experience with the unreamed tibial nail in open fractures up to Grade IIIb, a new monorail fixation system for callus distraction and segmental bone transport was devised. This Monorail system is composed of an unreamed intramedullary (IM) nail and a unilateral AO distraction device. The new fixation method and the preliminary clinical experience are reported here. Four patients who previously sustained Grades II-IIIb open tibial fractures had an average bony defect of 9 cm. Two patients had previous bony infections. All patients had had serial debridements and myocutaneous flaps were required in three patients. An unreamed IM nail was inserted, and the transport device was applied. After an osteotomy, segmental transport was carried out until docking was achieved. The external fixator was removed after interlocking of the transported segment. The mean duration of external fixation was 17.9 days/cm and the mean period until roentgenographic consolidation of the distraction and nonunion site was 41.2 days/cm. There were two pin-tract infections but no IM infections. One nail broke after osseous consolidation of the regenerate at the distal interlocking site and required exchange. The goal of transport was achieved in all cases without angular or rotational deformity or length discrepancy. There were no neurovascular injuries.


Collagen types. Molecular structure and tissue distribution.

The collagens are products of a superfamily of closely related genes. Currently, there are 13 described collagens encompassing at least 25 separate genes. The collagen molecules can be categorized into four classes. Class I consists of molecules that form the banded collagen fibers that are readily seen by routine electron microscopy. The banded fibers are heterogenous with respect to collagen type, containing at least two and often three collagen types in each fibril. This multiplicity is believed to effect the rate of fibril growth and the final fibril diameter. Class II contains collagens that adhere to the surface of the banded fibrils. The function of these molecules is not yet known. The third Class consists of molecules that form independent fiber systems. These include the basement membrane, beaded filaments, anchoring fibrils, and the network surrounding hypertrophic chondrocytes. The last class contains several collagens with unknown fiber forms, and whose functions are unclear. Tissues contain multiple fiber forms and therefore many individual collagen types. Bone is no different, and there are presently four known collagens in the bone cortex. This article summarizes knowledge of the structures and functions of the collagen superfamily.


Morphometric and physical investigations of segmental cortical bone autografts and allografts in canine ulnar defects.

Cortical bone grafts were implanted for six months in mature dogs using an osteoperiosteal 3-cm defect in the ulna to evaluate their respective morphometric and physical values compared with autografts. The bone-grafting material included fresh auto- and allografts, frozen and thimerosal preserved allografts, and partially demineralized bone allografts. The grafts were evaluated by roentgenograms, microradiograms, photon absorptiometry, porosity, fluorescence labeling measurements, and torsional loading at failure. Autografts achieved a better union score than the allografts, but intracortical bone porosity, percentage of cumulative new bone, and mineral apposition rate were not variables with statistical significance. Lamellar bone was found earlier and in greater quantity in autografts. Within the graft, new bone was deposited at a slower rate than in the recipient bone. Autografts showed less peripheral resorption and a greater torsional resistance than allografts. Photon absorptiometry demonstrated that nondemineralized allografts underwent a substantial loss of peripheral bone. This marked reduction in the outer diameter of the graft had more influence on torsional resistance than did the intracortical porosity of the graft. Demineralized allografts were osteoinductive in only 28% of the cases and appeared to respond in an all-or-nothing pattern. Frozen and thimerosal preserved allografts were the most acceptable substitutes to autografts.


Calvarial regeneration in primates with autolyzed antigen-extracted allogeneic bone.

The limited regenerative capacity of calvarial membranous bone provides an ideal system for investigation in the comparative physiology of bone regeneration. Cranial defects, 25 mm in diameter, were created in 24 adult male baboons (Papio ursinus). In each animal, defects were implanted with chemosterilized antigen-extracted, autolyzed allogeneic (AAA) bone, grafted with iliac corticocancellous grafts, or left ungrafted to monitor the spontaneous regeneration potential of the adult baboon calvaria. Antigen-extracted, autolyzed allogeneic bone implants were prepared from donor sub-adult baboon calvariae and processed so as to retain bone morphogenetic protein (BMP) in the bone matrix. Histomorphometric analysis of undecalcified sections (7-microns thick) prepared from specimens harvested at three, six, and nine months after surgery showed superior osteogenesis in AAA bone matrix implants, compared with autografts and untreated defects. The morphogenetic response was characterized by vascular invasion and mesenchymal cell aggregation after partial resorption and dissolution of the implanted matrix, followed by bone deposition at the calvarial interfaces, the pericranial and endocranial surfaces of the implants, and within the open diploic spaces of the implanted original AAA bone matrix. The superior osteogenesis in AAA bone implants appeared consistent with extensive osteoconductive invasion from the open diploic and endosteal spaces of the recipient calvariae. In addition, the finding of a delicate, trabecularlike bone, appositional to the central areas of the implanted matrix, suggests that AAA bone implants might also have acted as inductive substratum for bone differentiation.


The effects of fat interposition for central-physeal defects. A histologic study in rabbits.

The effects of autogeneic fat interposition in a central cylindrical physeal defect were observed in rabbits. A 3.6-mm longitudinal drill hole was made across the physis of the distal femur, bilaterally, in four- to six-week-old New Zealand rabbits. One side was filled with an autogeneic fat graft and the contralateral defect was left as a control. The rabbits were killed at intervals during the remaining growth period, and the defects were examined histologically. Although fat grafts reduced the rate of osseous bridging across the physis and allowed more longitudinal growth than controls, transverse regeneration of the physis did not occur in the eight-week period preceding closure. The lack of physeal regeneration across the gap may reflect an important difference between central and peripheral defects.


On the material and the tribology of alumina-alumina couplings for hip joint prostheses.

The yearly sphericity deviation ranged from 0.03 mu to 3.7 mm in 48 retrieved implants with alumina--alumina bearing balls and cups. Excessive amounts of wear are predominantly design dependent or caused by malalignment. But the abrasion phenomena occurring in the cup centers and in the corresponding ball areas are related to unfavorable function zones. The influence of the lubricating gap geometry as studied in laboratory tests shows the form of sphericity deviations to be of decisive importance for wear and friction, if extended over small angles. Then, the contact stresses attributable to the actual effective curvatures of the bearing exceed the resistance to abrasion of the material under boundary lubrication conditions. There are remarkable differences between the early and actual material quality. Based on the state of knowledge of material aspects of wear criteria for the optimization of material and design, promising tolerable wear rates may be achieved.


Long-term effects of alumina components in total hip prostheses.

Six pairs of alumina components of Ceraver-Ostéal total hip prostheses, which were implanted from nine to 12 years, were studied. In the load-bearing areas, the wear takes the form of relief polishing. The depth of wear, after a running-in period, is less than 0.3 microns and then reaches an equilibrium. In four cases, there was no displacement of the sockets and wear tracks were formed on the femoral heads, the sockets being worn on their periphery, never on the apex. In the case of two persons weighing more than 90 kg, two wear tracks were observed on the heads, corresponding to walking and raising from a seated position. In the worst case, the depth of the wear track was 44 microns and the weight of alumina debris was estimated to be 18 mg.


Ten-year survivorship of cemented ceramic-ceramic total hip prosthesis.

In the first 187 consecutive alumina-alumina combination hip arthroplasties performed from 1977 to 1979, both components were cemented with conventional techniques. At ten-year follow-up evaluation, 87 patients were reviewed or interviewed by telephone, 37 were dead, 39 were lost to follow-up evaluation, and 24 failures were reoperated on before the end of ten years. The major cause of failure was aseptic loosening of the acetabular component (15 failures). Fracture of the socket and of the femoral head occurred in five patients in this series. However, these complications were not seen with components manufactured after 1979. At the end of ten years, survivorship analysis depicted a 82.59% survival rate when reoperation was considered as failure and a 88.57% rate when reoperation for aseptic loosening was considered as failure. The femoral component had a 99.16% survival rate and the acetabular component had an 88.57% survival rate when reoperation for aseptic loosening was considered as failure. Age, appearance of a two- or three-zone demarcation at the intermediate follow-up evaluation, and outer diameter of the acetabular component were the major parameters influencing the results. Better results observed in the population younger than 50 years of age may be related to the small amount of wear debris produced by the alumina-alumina combination. This combination in hip prosthesis is secure, but should be implanted in young and active patients; the outer diameter of the acetabular component must be at least 50 mm. The major problem that remains is the socket's fixation. It could be improved by a design modification, by choosing another mode of fixation, or both.


Sixteen-years' experience with ceramic hip prostheses.

The introduction of alumina ceramic combined with the self-locking principle by surface increase has many followers. There is no manufacturing company in the world that does not produce self-locking hip prostheses with ceramic components. Despite increased interim results with conventional prostheses by improved cement technique, the self-locking principle with wear resistant ceramic components is better, at least in young, active patients.


Ten- to 14-year results of a ceramic hip prosthesis.

One hundred total hip arthroplasties with a cementless aluminum oxide socket and ball with different types of cemented metal femoral stems were performed from 1974 to 1979. All were primary implantations. These cases were recently reviewed in a ten- to 14-year follow-up evaluation. Despite extensive laboratory testing of the ceramic material, a significant number of cases resulted in a very unfavorable result such as extensive wear, ball fracture, or migration of the socket. Whereas the patients had died or could no longer be traced in the case of 23 prostheses, there were 25 prostheses that had already been exchanged at the time of review for mechanical reasons (two stem fractures, eight ceramic ball fractures) and for component loosening attributable to wear of the alumina components. The remaining 52 prostheses still in place had good clinical results in 80%. However, roentgenographic evaluation of these prostheses revealed signs of loosening in six femoral components and in three sockets. Migration of more than 5 mm was evident in 24 sockets (46% of surviving prostheses). Although this had caused loosening in only three sockets at the time of review, further migration up to the limits of the acetabular region would be a major reason for future failures.


Comparison of cemented ceramic and metal-polyethylene coupling hip prostheses in ankylosing spondylitis.

Two groups of patients suffering from ankylosing spondylitis were treated by total hip arthroplasty. Twenty-one patients (37 hips) were treated with cemented metal-polyethylene prosthesis, whereas 18 patients (36 hips) had cemented ceramic coupling implants. The two groups had similar preoperative clinical data. The average follow-up period was seven to eight years for both. Each patient was graded clinically (pain, function, range of motion, deformities) and roentgenographically (radiolucent lines, etc.). Patients with metal-polyethylene implants showed important modifications of the bone around the implant. Clinical and roentgenographic results were relatively good in patients with ceramic implants. The results underline the importance of the friction coupling of the implant.


Comparison of alumina-polyethylene and metal-polyethylene in clinical trials.

The dimensional changes of hip sockets of Müller-type total endoprostheses is the subject of this article. Regular anteroposterior roentgenographs of the pelvis were taken to determine the orientation of the center of the prosthetic head in relation to the wire marker of the polyethylene cup. Three different materials used for the femoral balls and matched with polyethylene as socket material were investigated, and the results of the displacement of the ball into the socket were compared. Both creep and wear contribute to the dimensional changes of the hip sockets; the proportional amount of each mechanism is not known. Data from laboratory examinations suggest a relatively high rate of creep in the first six months after implantation. With longer periods, the dimensional changes are predominately caused by wear. In the beginning of joint function, measurements show a high rate of the yearly dimensional changes. The head shifts up to 0.5 mm per year and diminishes after five years to rates of 0.1-0.2 mm, respectively. All dimensional changes that exceed a shift of the head of 0.2 mm per year are considered to be unfavorable and to contribute to loosening of the implants. Using metallic balls (Protasul-2), 64% had a wear rate of less than 0.2 mm; of those using Prostasul-10, 77% had lower rates than 0.2 mm. In patients where ceramic balls were implanted, the displacement rate was below 0.2 mm per year in 95%. Therefore, ceramic seems to be the most favorable material.


Alumina versus polyethylene in total knee arthroplasty.

The cementless alumina total knee prosthesis, which uses alumina in the portions coming in contact with the bone and a combination of alumina and ultra-high molecular-weight polyethylene (UHMWPE) in the sliding portions, is referred to as a total condylar. Alumina total knee arthroplasty was performed on 137 patients, including 103 rheumatoid arthritis (RA) and 34 osteoarthrosis (OA) patients, from January 1982 to February 1985. The follow-up period was seven years 11 months and four years ten months, respectively. At follow-up evaluation, 108 patients were available for clinical and roentgenographic examinations, amounting to a 79% follow-up rate. At follow-up examination, 67 joints (62%) were completely pain free and 28 joints (26%) caused slight pain on bearing weight. Walking ability was recovered moderately in RA and markedly in OA. In RA, 14 of 84 knees were cemented and one knee was treated with loosening. Of 72 cementless implantations, 55 sustained displacing distally and one sustained loosening in the tibia, whereas 31 sustained displacing proximally and six sustained loosening in the femur. In OA, 21 cementless knees had 17 displacings in the tibia, and ten displacings and two loosenings in the femur. Scanning electron microscopy (SEM) observation of the UHMWPE surface in tibial plates revealed smoothing and burnishing. Alumina is far superior to metal for the sliding part, although it is not always best for the portion in contact with the bone. To resolve these problems, for cementless fixation, anchoring portions of Ti alloy and alumina implants were covered with beads and coated with hydroxyapatite. For cement fixation, "the interface bioactive bone cement technique" interposing hydroxyapatite granules between bone and cement was performed.


Thrombolysis in high risk patients.

The advent of intra-arterially administered thrombolytic agents of minimal antigenicity, together with small gauge good torque control catheters, enables thrombolysis to be used in patients that may previously have been deemed unsuitable for thrombolytic therapy. Thrombolysis may be used even in the presence of factors formerly and empirically considered to be contra-indications. The continued use of thrombolytic agent may also be warranted despite iatrogenic complications such as vessel wall perforation, particularly if the alternative is major amputation. We report on a series of eight patients in whom intra-arterial tissue plasminogen activator was used despite either recent vascular surgery, or iatrogenic vessel perforation. Suggestions for the use of thrombolysis in high risk patients and following iatrogenic complications are discussed.


Proton NMR relaxation times in the normal human liver at 0.08 T.

The spin-lattice (T1) and spin-spin (T2) relaxation times of liver in 42 normal volunteers (21 male and 21 female) were measured using a calibrated 0.08 T resistive imager capable of accurate and reproducible relaxometry. T1 was determined using an interleaved gradient echo saturation recovery and inversion recovery technique and T2 using a four-echo Carr-Purcell-Meiboom-Gill sequence. The ranges obtained were T1 = 213 +/- 14 ms and T2 = 66 +/- 5 ms. More specific ranges were obtained for each sex and for younger and older subjects. A small variation in T1 was found between older (greater than 40 years) and younger (less than 40 years) subjects, but no such effect was observed in the case of T2. No significant variations were found when female volunteers were imaged at weekly intervals through the menstrual cycle, when a male volunteer was imaged repeatedly over the course of several months or when male volunteers consumed small quantities of alcohol.


Undifferentiated carcinoma of the thyroid gland: sonographic findings.

We report high resolution sonographic (7.5 MHz) findings in four cases of undifferentiated carcinoma of the thyroid gland. Sonographic findings in these four cases included poorly marginated, hypoechoic masses associated with calcifications, and invasion of adjacent cervical structures. A knowledge of the sonographic features of undifferentiated carcinoma of the thyroid gland is of clinical importance, since the tumour has a grave prognosis, quite different from the relatively favourable prognosis of well differentiated thyroid carcinoma.


The sonographic appearances in postpartum thyroiditis.

During the postpartum period about 50% of women with circulating thyroid autoantibodies develop a transient autoimmune thyroiditis. To determine the sonographic appearances in postpartum thyroiditis (PPT), serial ultrasound (US) scans of the thyroid were performed in 135 postpartum women who were divided into three clinical groups: Group 1, 37 antibody positive subjects who developed PPT; Group 2, 28 antibody positive subjects in whom thyroid function remained normal; Group 3, 70 antibody negative controls. Thyroid hypoechogenicity was observed in 14/31 patients (45%) who were scanned between 4 and 8 weeks postpartum and who subsequently developed PPT (Group 1) compared with 4/24 patients (17%) in Group 2 (P less than 0.05) and 1/65 patients (1.5%) in Group 3 (P less than 0.001). In antibody positive patients, the positive predictive value of an abnormal scan during this period was 78%. Between 15 and 25 weeks postpartum thyroid hypoechogenicity was present in 32/37 patients (86%) in Group 1 compared with 11/28 patients (39%) in Group 2 (P less than 0.001) and 2/70 patients (3%) in Group 3 (P less than 0.001). Sonographic abnormality persisted beyond 32 weeks postpartum in 36/41 antibody positive patients (87%) who had exhibited thyroid hypoechogenicity earlier during the study and who had late scans. The characteristic US appearance in PPT is thyroid hypoechogenicity. The role of sonography in the prediction, diagnosis and follow up of patients with PPT is discussed.


Gigantiform cementoma occurring in two populations, London and Hong Kong.

The gigantiform cementoma presents as multiple opacities in the tooth-bearing areas of the jaws. Sixteen cases are presented, six of British Negresses and 10 of Hong Kong Chinese females. The differential diagnosis and management are briefly reviewed.


CT findings in paranasal aspergillosis.

Computed tomographic (CT) scan of eight cases of paranasal sinus aspergillosis were reviewed. Different CT patterns were observed such as areas of high densities, linear interlacing network of high density, radiolucent thin rim periphery to the masses, calcification, expansion of involved sinuses and bone erosion. Two cases of invasive type showed extension beyond the sinuses into the orbit and intracranially simulating a malignant tumour. The findings are similar to those described by previous authors. The differential diagnosis is also discussed.


Abdominal radiography in suspected 'body packers'.

Drug smuggling by intra-abdominal concealment is now a world-wide problem. This paper describes the establishment of a plain radiography service to assist customs officers of Manchester International Airport (MIA) in their work. Over a 2 1/2 year period, 158 suspected 'body packers' were radiographed, resulting in nine positive detections. The existence of the service has resulted in the apparent abandonment of MIA as a port of entry by an organized group of cocaine smugglers. Practical and ethical problems are described. This service is felt to be essential by the customs officers and a valuable service to society by the radiologists and hospital authorities concerned.


Soft-tissue localization of 99mTc-hydroxymethylene diphosphonate due to interaction with calcium.

Soft tissue localization of 99mTc-labelled bone imaging agents is often associated with high calcium levels either locally or systemically. This could be due to the formation of a large molecular complex after administration of the radiopharmaceutical. We have investigated the formation of such a complex between 99mTc-hydroxymethylene diphosphonate (HMDP) and calcium by a number of techniques. The results indicate that 99mTc-HMDP is a colloidal preparation which may contain particles up to 280 nm in size, and that the labelled colloid may aggregate in the presence of calcium salts forming particles up to 3 microns. Such particles are too large to permit free diffusion across vascular epithelium but large enough to localize in the liver or lungs. It is suggested that this interaction may be responsible for soft tissue localization of the technetium-labelled bone imaging agents. In vivo the radiolabelled complex in a mixture of 99mTc-HMDP and calcium chloride localizes to a significantly larger extent in liver, spleen and muscle and less in bone compared with 99mTc-HMDP diluted with saline. The increased liver and spleen uptake can be prevented by prior administration of non-radioactive colloid but this does not significantly improve the bone uptake of the 99mTc-HMDP/calcium chloride mixture. The clinical relevance of these findings lies in their possible explanation for soft-tissue uptake and poor bone accumulation of the technetium-labelled diphosphonates in some patients. This may be particularly important in evaluating quantitative bone scans, especially if serial scanning is done to monitor disease progress or therapy since local or systemic calcium levels may change between scans.


Tc HMPAO-labelled white cell scintigraphy in Cröhn's disease of the small bowel.

99mTechnetium-hexamethyl propylene amine oxime (99mTc HMPAO) white cell scintigraphy is increasingly used in the investigation of inflammatory bowel disease. It is now an accepted technique in the assessment of patients with colitis, although its role in small bowel is less clear. A retrospective study was performed on patients with jejunal and ileal Cröhn's disease to assess the sensitivity, reliability and usefulness of this technique in small bowel disease. Tc HMPAO scintigraphy was compared with barium studies, clinical outcome and, where available, subsequent histology. Good correlation between this technique and barium studies was found in 14 out of 18 patients and additional information was provided in two patients. A single false positive scan highlights the importance of early scanning in avoiding errors of interpretation due to the normal hepatobiliary excretion of activity that occurs with this pharmaceutical.


Double blind comparison of Iomeprol 350 and Iopamidol 340 in intravenous digital subtraction angiography for peripheral vascular disease.

A randomized double blind study was undertaken to compare the diagnostic efficacy and side effects of a new non-ionic contrast medium Iomeprol with a commonly used one--Iopamidol. Visual and densitometric comparison was made of intravenous digital subtraction angiograms performed for peripheral vascular disease. The results show the two media to be similar both in imaging quality and in the incidence of associated side effects. Ninety-eight per cent of the intravenous digital subtraction angiograms were assessed as adequate for clinical management by the vascular surgeon.


The prevalence of enlarged mediastinal lymph nodes in asbestos-exposed individuals: a CT study.

Patients with cryptogenic fibrosing alveolitis have a higher prevalence of enlarged mediastinal lymph nodes compared with the normal population. To determine whether or not this observation applies to individuals with asbestos-induced pulmonary fibrosis the high resolution computed tomography (CT) scans of 14 patients with definite asbestosis and 11 age-matched cases with benign asbestos-induced pleural disease, but no lung disease, were re-imaged on soft tissue settings. The site, size and number of mediastinal lymph nodes equal to, or greater than, 1.2 cm were recorded. In the asbestosis group 14 out of 14 patients had at least one enlarged lymph node with an average number per individual of four (range 1-10). In the control group two out of 11 patients each had one minimally enlarged lymph node. We conclude that mediastinal lymph node enlargement occurs frequently in asbestosis: awareness of this is important in the investigation of malignant disease in patients with asbestosis.


Patterns of breast calcification in patients on renal dialysis.

Patients on renal dialysis are prone to form areas of metastatic calcification in soft tissues. In this study we have analysed the mammograms of 16 women on renal dialysis and compared them with a control group of 32 women attending for routine mammographic screening. We found a significant increase in vascular and parenchymal calcifications in the women on renal dialysis. Ductal calcifications were no more prevalent in the patients on dialysis, and in no case did the calcification simulate malignancy.


Case report: limey urine.

A case is described of multiple tiny bladder stones giving rise to unusual ultrasound and plain radiograph appearances of a calcified sediment within the bladder.


Case report: granular cell tumour of the breast.

We describe a granular cell tumour in the breast of a 62-year-old woman. This tumour is unusual in the breast, and though usually benign, may be misinterpreted as cancer.


Case report: the ultrasound diagnosis of enterocutaneous fistula.

The sonographic diagnosis of post-operative enterocutaneous fistula is presented. This has not previously been reported in the English literature.


Case report: acute subdural haematoma--an unusual presentation of a meningioma.

Acute subdural haemorrhage is usually the result of a head injury, but when it occurs without a history of trauma, an underlying cause must be suspected. An unusual case is described of an acute subdural haematoma in association with a parasagittal meningioma. This is a rare but serious complication of a meningioma and outcome depends upon prompt removal of the tumour.


Case report: lipoma of the liver--ultrasound, CT and MR imaging.

A case of lipoma of the liver is presented; ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) findings are reviewed and compared with previous reports. The ultrasound pattern and appearance of the tumour in CT as well as MRI are discussed.


Case report: fatal non-menstrual toxic shock in a Chinese woman.

A fatal case of non-menstrual toxic shock syndrome (TSS) is reported in a Chinese woman, which was associated with a vaginal Staphylococcus aureus infection. Cerebral haemorrhage and vasogenic white matter oedema was shown in cranial computed tomography (CT) before the terminal event.


Multielement visual tracking: attention and perceptual organization.

Two types of theories have been advanced to account for how attention is allocated in performing goal-directed visual tasks. According to location-based theories, visual attention is allocated to spatial locations in the image; according to object-based theories, attention is allocated to perceptual objects. Evidence for the latter view comes from experiments demonstrating the importance of perceptual grouping in selective-attention tasks. This article provides further evidence concerning the importance of perceptual organization in attending to objects. In seven experiments, observers tracked multiple randomly moving visual elements under a variety of conditions. Ten elements moved continuously about the display for several seconds; one to five of them were designated as targets before movement initiation. At the end of movement, one element was highlighted, and subjects indicated whether or not it was a target. The ease with which the elements in the target set could be perceptually grouped was systematically manipulated. In Experiments 1-3, factors that influenced the initial formation of a perceptual group were manipulated; this affected performance, but only early in practice. In Experiments 4-7, factors that influenced the maintenance of a perceptual group during motion were manipulated; this affected performance throughout practice. The results suggest that observers spontaneously grouped the target elements and directed attention toward this coherent but nonrigid virtual object. This supports object-based theories of attention and demonstrates that perceptual grouping, which is usually conceived of as a purely stimulus-driven process, can also be governed by goal-directed mechanisms.


The monolingual nature of speech segmentation by bilinguals.

Monolingual French speakers employ a syllable-based procedure in speech segmentation; monolingual English speakers use a stress-based segmentation procedure and do not use the syllable-based procedure. In the present study French-English bilinguals participated in segmentation experiments with English and French materials. Their results as a group did not simply mimic the performance of English monolinguals with English language materials and of French monolinguals with French language materials. Instead, the bilinguals formed two groups, defined by forced choice of a dominant language. Only the French-dominant groups showed syllabic segmentation and only with French language materials. The English-dominant group showed no syllabic segmentation in either language. However, the English-dominant group showed stress-based segmentation with English language materials; the French-dominant group did not. We argue that rhythmically based segmentation procedures are mutually exclusive, as a consequence of which speech segmentation by bilinguals is, in one respect at least, functionally monolingual.


Common region: a new principle of perceptual grouping.

A new principle of grouping is proposed that is based on elements being located within a common region of space. Demonstrations analogous to Wertheimer's original displays show that this factor strongly influences perceived grouping and is capable of overcoming the effects of other powerful grouping factors such as proximity and similarity. Grouping by common region is further shown to depend on perceived depth relations, indicating that it is influenced by processes that occur after at least some depth perception has been achieved. Further demonstrations suggest that it is dominated by the smallest background area and that it can follow a hierarchical embedding scheme. It is argued that common region cannot be reduced to the effects of proximity, closure, or any other previously known factor and therefore constitutes a genuinely new principle of grouping.


A review on classical swine fever infections in pigs: epizootiology, clinical disease and pathology.

A review is given on classical swine fever (CSF) including epizootiology, clinical disease and pathology. Under the item of epizootiology the history of CSF is briefly summarized. Ways of transmission are described with special reference to CSF in wild boars. The chapter about clinical disease includes the description of different courses of CSF such as peracute, acute, subacute form and chronic disease with reference to the course of transplacental infection and fate of the progeny associated with the "carrier sow syndrome". The most typical lesions in CSF are summarized in the chapter of pathology.


A tissue culture vaccine with lapinized chinese (LC) strain of hog cholera virus (HCV).

The lapinized chinese (LC) strain of hog cholera virus (HCV), was adapted to grow in a cell line from minipig kidney (MPK) where it reached a titer, as determined by immunofluorescence, significantly higher than in rabbits. Inasmuch as the immune serum to HCV neutralized the culture-adapted virus, it was concluded that its antigenicity did not undergo any change after adaptation to MPK cells. The MPK-LC adapted virus (MPK-LC-HCV) showed also a higher immunogenic activity in rabbits, in comparison with the original LC virus. The MPK-LC-HCV protected pigs against challenge infection with virulent HCV. Thus, the vaccinated pigs did not show any clinical signs of disease, nor have they been responsible of virus shedding after they were exposed to the challenge infection 1 month or 6 and 11 months later. All vaccinated pigs seroconverted after vaccination and the antibody titers were on the same range of those reported in pigs vaccinated with the traditional vaccine prepared in rabbits. In the same pigs the antibody concentration underwent a booster effect following challenge infection. It was suggested the MPK-LC-HCV vaccine as an alternative product that might be used to prevent HCV infection. prevent HCV infection.


Hulka Clip application as a potential cause of chronic pelvic pain.

A case report of an isolated hydrosalpinx resulting from the placement of two Hulka Clips on the same fallopian tube is presented. This is a previously unreported complication of mechanical sterilization and is suggested as a possible cause of chronic pelvic pain.


Progesterone-releasing vaginal rings for use in postpartum contraception. I. In vitro release rates of progesterone from core-loaded rings.

Vaginal rings of Dow Corning 382 Silastic polymer, having identical outside dimensions, were fabricated to contain cores of different diameters loaded with 25% w/w progesterone. Elution of rings was carried out in continuously flowing baths of isotonic saline at 37 degrees C and quantities of progesterone released in 24 h periods measured for up to 128 days. Release of the steroid was shown to be a membrane diffusion-controlled process, modified by the development of a gradually increasing zone of depletion at the core surface. Rings of a suitable core diameter were selected to give initial release of 5 mg/24 h progesterone and sterile batches of these rings, prepared for WHO-sponsored clinical studies in post-partum, lactating women, were shown to give highly consistent and reproducible rates of in vitro drug delivery. A comparison was made with the in vitro release rates of rings containing a homogeneous dispersion of progesterone.