HYALURONIDASES OF BACTERIAL AND ANIMAL ORIGIN

Hyaluronidase has been investigated in various strains of pneumococci and hemolytic streptococci, and in some material of animal origin. The enzyme activity was measured by a viscosimetric method using as a substrate a fluid containing hyaluronic acid as the viscous component, and by the hydrolysis of pure hyaluronic acid into its reducing components. In pneumococci the enzyme was demonstrated in all types and in all strains tested, including smooth and rough forms of Types I, II, III, and VI. In hemolytic streptococci the enzyme from strain H44, group A, reported previously, was further investigated. In this strain, as well as in other hemolytic streptococci containing the enzyme, great variability of the enzyme concentration was found. Furthermore, the enzyme proved to be very labile, giving in the viscosimetric measurements a typical stoppage of the activity initially present. In 13 out of 14 other strains of group A organisms investigated, no enzyme was demonstrable, but the variation in activity in the enzyme-active strains renders the negative findings inconclusive. A very active enzyme, though of great variability, was found in one group C strain. The enzyme was prepared from the leech in confirmation of the work of Claude. The enzyme from testis showed a maximum at pH 4.4 in contrast to the optimum of 5.8 in pneumococcal, streptococcal, and Cl. welchii preparations. The pH curve of the testis enzyme indicated, however, a second optimum coinciding with that of the bacterial enzymes. The hydrolysis further indicated a break at about 50 per cent hydrolysis, indicating primarily the hydrolysis down to aldobionic acid units. The depolymerizing action of testis enzyme is more marked than that of pneumococcal enzyme. The results have been interpreted as due to the presence of two enzymes, one attacking the long chain molecule, the other hydrolyzing the aldobionic acid formed. The enzyme was further prepared from beef spleen. Here the hydrolysis of beta-glucuronides was compared to that of hyaluronic acid. The two actions apparently are catalyzed by two distinct enzymes. Enzyme preparations were further obtained from rabbit skin. Since hyaluronic acid has also been found in the skin, this organ may play a considerable rôle in the metabolism of hyaluronic acid. In addition to hyaluronic acid, it has been shown that hyaluronidases also hydrolyze the sulfuric acid containing polysaccharide of the cornea. This polysaccharide has previously been characterized as a natural sulfuric acid ester of hyaluronic acid. The pneumococcal enzyme preparations also attacked a polysaccharide acid prepared from submaxillary gland, which is not hyaluronic acid. However, it is believed that this hydrolysis is due to a second enzyme contained in the preparations. The testis enzyme, on the other hand, attacked chondroitinsulfuric acid and also contained a sulfatase. The depolymerizing action of hyaluronidase has been discussed. It is concluded that depolymerization and hydrolysis are probably due to the same enzyme attacking hyaluronic acid. It is suggested that the first attack of the enzyme does not cause an opening of glucosidic linkages. The available evidence indicates that the viscosity of the natural fluids is not due to macromolecules but to micellae formation, and that these micellae are depolymerized by the enzymatic reaction. It is assumed that the depolymerization is due to a primary enzyme-substrate reaction, which in itself is insufficient to open the glucosidic linkages. The latter reaction involves further steps. The relationship between hyaluronidase and "spreading factor" has been discussed anew. Though more data have been reported pointing to the identity of hyaluronidase and "spreading factor," our inability to demonstrate hyaluronidase in streptococcal material of high "spreading" potency, is still a serious obstacle to the unitarian theory. However, it seems possible that the streptococcal material may contain reversibly inactive enzyme which may be reactivated in vivo.

THE HYDROLYSIS OF HYALURONIC ACID BY BACTERIAL ENZYMES

An improved method is described for preparing the enzyme which hydrolyzes the polysaccharide acid contained in vitreous humor, umbilical cord, synovial fluid, and the mucoid phase of group A hemolytic streptococci. Preparations have been obtained from pneumococci, group A hemolytic streptococci, Clostridium welchii, and from splenic tissue, which display the same specific activity. Evidence is presented to show that the hydrolytic enzyme is not the same as that responsible for the lysis of pneumococci. In pneumococci and hemolytic streptococci the major portion of the enzyme is bound to the cell structure. The enzyme from Clostridium welchii is associated with other carbohydrate-splitting enzymes in the culture medium and not with the bacterial cells. It is suggested that the disappearance of the mucoid capsule of group A hemolytic streptococci is due to enzymatic hydrolysis of the acid polysaccharide. The relation between enzyme activity and the virulence and invasiveness of group A hemolytic streptococci is briefly considered.

THE RELATIONSHIP BETWEEN SPREADING FACTOR AND HYALURONIDASE

A comparative study of spreading factor and hyaluronidase in preparations from various sources revealed the following points of similarity and dissimilarity in the two reactions. 1. Similarities: (a) All preparations containing hyaluronidase also produced spreading. (b) Heating at 65° and 100°C. for 30 minutes produced a comparable effect on both reactions. (c) The demonstration of the presence of hyaluronic acid in skin offers a plausible explanation for the mechanism of spreading on the basis of hyaluronidase activity. 2. Dissimilarities: (a) No parallelism was observed in the degree of activity of spreading factor and hyaluronidase in the same preparations. (b) All preparations which produced spreading did not contain hyaluronidase. (c) Antisera to hyaluronidase preparations specifically and completely inhibited the activity of the homologous enzyme but did not inhibit the spreading factor in the same preparations. The significance of the similarities and dissimilarities between the two reactions is discussed. It is concluded that while hyaluronidase may play a rôle in the spreading reaction the phenomenon is a complex one and cannot be explained on the basis of a simple chemical reaction.

Perceived parental rearing in subjects with obsessive-compulsive disorder and their siblings

OBJECTIVE

Perceived parenting in patients suffering from obsessive-compulsive disorder (OCD) is examined. We attempted to overcome some methodological limitations of prior studies by taking age of onset, parental OCD and comorbid depression into consideration. In addition, we included data from unaffected siblings to corroborate information on parental rearing.

METHOD

One hundred and twenty-two cases with OCD and 41 of their siblings as well as 59 healthy controls and 45 of their siblings completed the German short-version of the EMBU (FEE).

RESULTS

Obsessive-compulsive disorder cases reported less parental warmth and more parental rejection and control. Further analyses indicated that parenting is also associated with OCD in cases with late onset and cases without parents affected by OCD. OCD cases with comorbid depression described their parents particularly negatively. Data from siblings indicated good validity of perceived parenting in OCD.

CONCLUSION

This study provides further evidence for dysfunctional child rearing being relevant to the development of OCD and depression.

Stroke events, and case fatalities in Switzerland based on hospital statistics and cause of death statistics

OBJECTIVE

In Switzerland there is a shortage of population-based information on stroke incidence and case fatalities (CF). The aim of this study was to estimate stroke event rates and both in- and out-of-hospital CF rates.

METHODS

Data on stroke diagnoses, coded according to I60-I64 (ICD 10), were taken from the Federal Hospital Discharge Statistics database (HOST) and the Cause of Death database (CoD) for the year 2004. The number of total stroke events and of age- and gender-specific and agestandardised event rates were estimated; overall CF, in-hospital and out-of-hospital, were determined.

RESULTS

Among the overall number of 13 996 hospital discharges from stroke (HOST) the number was lower in women (n = 6736) than in men (n = 7260). A total of 3568 deaths (2137 women and 1431 men) due to stroke were recorded in the CoD database. The number of estimated stroke events was 15 733, and higher in women (n = 7933) than in men (n = 7800). Men presented significantly higher age-specific stroke event rates and a higher age-standardised event rate (178.7/100 000 versus 119.7/100 000). Overall CF rates were significantly higher for women (26.9%) than for men (18.4%). The same was true of out-of-hospital CF but not of in-hospital CF rates.

CONCLUSION

The data on estimated stroke events obtained indicate that stroke discharge rate underestimates the stroke event rate. Out-of-hospital deaths from stroke accounted for the largest proportion of total stroke deaths. Sex differences in both number of total stroke events and deaths could be explained by the higher proportion of women than men aged 55+ in the Swiss population.

Blood pressure and heart rate immediately after termination of short-term ventricular fibrillation

BACKGROUND

Implantable cardioverter/defibrillators (ICDs) can detect ventricular fibrillation (VF) and terminate it. For determining the optimal defibrillation threshold, ventricular fibrillation is repetitively induced and terminated with DC shocks. Depending on the protocol, several fibrillation/defibrillation sequences are mandatory before the final implantation of an ICD. This procedure provides an elegant human model of circulatory arrest and resuscitation.

PATIENTS AND METHODS

In anesthetized 73 patients (15 females) of on the average 60+/-11 years, the end-expiratory pressure was set to zero. Left ventricular pressure (LVP) was monitored with a microtip-catheter, central venous pressure (CVP) through a cannula which was advanced into the superior V. cava. ECG was recorded. After testing, a monoexponential function was found to best fit the time courses of LVP, CVP and heart rate. Data are mean+/-S.D.

RESULTS

After termination of circulatory arrest, peak LVP increased with a time constant tau of 9.2+/-4.2 beats, CVP decreased with tau=2.8+/-1.5 beats, and RR-intervals decreased with tau=4.3+/-3.5 beats. Correlations between prefibrillatory values and steady-state values after termination of fibrillation were high: peak LVP: r=0.78; CVP: r=0.95; RRI: r=0.82.

SUMMARY

After DC termination of VF, the heart 'finds' relatively quickly a steady-state rhythm at the prefibrillatory level (22 beats), thereby normalizing CVP almost in parallel (14 beats). Peak LVP plateaus only after about 40 beats, although reasonable arterial pressures are reached within the first beats. Our data are limited to periods of ventricular fibrillation of no longer than 60s, which limits the generalisability to the setting of clinical cardiac arrest.

Likelihood calculations to evaluate experimental designs to estimate genetic variances

Mixed model analyses via restricted maximum likelihood, fitting the so-called animal model, have become standard methodology for the estimation of genetic variances. Models involving multiple genetic variance components, due to different modes of gene action, are readily fitted. It is shown that likelihood-based calculations may provide insight into the quality of the resulting parameter estimates, and are directly applicable to the validation of experimental designs. This is illustrated for the example of a design suggested recently to estimate X-linked genetic variances. In particular, large sample variances and sampling correlations are demonstrated to provide an indication of 'problem' scenarios. Using simulation, it is shown that the profile likelihood function provides more appropriate estimates of confidence intervals than large sample variances. Examination of the likelihood function and its derivatives are recommended as part of the design stage of quantitative genetic experiments.

Large arachnoid granulations involving the dorsal superior sagittal sinus: findings on MR imaging and MR venography

BACKGROUND AND PURPOSE

Large arachnoid granulations (AG) within the dorsal superior sagittal sinus (SSS) have been incompletely characterized and can be confused with pathology. This report reviews the characteristics of these anatomic structures to establish common imaging features that allow differentiation from pathology.

MATERIALS AND METHODS

Twelve cases of large AG in the dorsal SSS are presented, identified by MR imaging. Signal intensity characteristics, size, location, venographic appearance, and association with adjacent venous and osseous structures were documented.

RESULTS

A defect in the dura of the SSS was seen in all of the cases communicating with the subjacent subarachnoid space. The average size of the AG was 8.1 x 9.4 x 10.0 mm (range, 4-19 mm). Ten produced calvarial remodeling, and 11 were in the direct vicinity of the lambda. On T2-weighted images, all were hyperintense to the brain. On T1-weighted images, 8 were hypointense and 4 were hypointense with mixed areas of isointense signal intensity. All of the AGs were associated with cortical venous structures entering the sinus. On MR venography, AGs appeared as focal protrusions into the sinus, displacing, distorting, and narrowing the sinus lumen. Seven patients had headache without other visible cause on MR imaging, and 4 were initially interpreted as thrombosis or tumor.

CONCLUSION

Large AGs can occur in the dorsal SSS. They are well-defined projections of the subarachnoid space into the sinus, can cause luminal narrowing and calvarial remodeling, and have typical signal intensity characteristics, position, and morphology differentiating them from other pathology. Association with patient symptoms is uncertain.

Multivariate analyses of carcass traits for Angus cattle fitting reduced rank and factor analytic models

Multivariate analyses of carcass traits for Angus cattle, consisting of six traits recorded on the carcass and eight auxiliary traits measured by ultrasound scanning of live animals, are reported. Analyses were carried out by restricted maximum likelihood, fitting a number of reduced rank and factor analytic models for the genetic covariance matrix. Estimates of eigenvalues and eigenvectors for different orders of fit are contrasted and implications for the estimates of genetic variances and correlations are examined. Results indicate that at most eight principal components (PCs) are required to model the genetic covariance structure among the 14 traits. Selection index calculations suggest that the first seven of these PCs are sufficient to obtain estimates of breeding values for the carcass traits without loss in the expected accuracy of evaluation. This implied that the number of effects fitted in genetic evaluation for carcass traits can be halved by estimating breeding values for the leading PCs directly.

A phase II clinical study of dendritoma vaccination combined with low dose interleukin-2 in advanced melanoma patients

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Background: The use of the fusion product of dendritic cells (DC) and tumor cells as a tumor vaccine represents one of the most promising approaches for cancer immunotherapy. We have developed a novel technology that instantly isolates the hybrids (Dendritomas) from the fusion mixture of DCs and tumor cells and thereby maintains tumor cellular diversity. Animal studies demonstrated that Dendritomas are superior activators of tumor cell specific antitumor immunity compared to fusion mixtures; and phase I clinical studies in advanced melanoma and renal cell carcinoma patients demonstrated that Dendritomas can be safely administered to cancer patients and are able to stimulate immunological and clinical responses in some of the patients. Methods: In order to determine the efficacy of Dendritoma vaccines, we designed a small phase II clinical trial in which individualized Dendritomas are manufactured from and injected into 15 stage IV melanoma patients. In order to boost the antitumor immune responses, a low dose interleukin-2 regime was followed only after the first Dendritoma vaccine. The patients received various numbers of vaccines (1 to 6) at six-week intervals. Clinical responses defined as complete response (CR), partial response (PR), stable disease (SD), mixed response (MR), progressive disease (PD), and no evidence of disease (NED) are monitored. The survival of the patients are monitored as well. Results: Twelve weeks after the first vaccine, three patients were NED; four patients were SD; two patients were PD/MR; and six patients were PD. At the time of the submission of this abstract, two patients were still NED and the median survival was 684 days with twelve of the fifteen patients (80%) surviving more than 431 days and eleven of fifteen patients (73%) surviving more than 519 days. Seven out of fifteen patients (47%) are still alive. Conclusions: The data from this small phase II study demonstrated that Dendritoma therapy combined with low dose IL-2 or other adjuvants may represent an effective therapy for melanoma patients and/or other cancer patients.

No significant financial relationships to disclose.

Genetic principal components for live ultrasound scan traits of Angus cattle

Multivariate restricted maximum likelihood analyses were carried out for a large data set comprising records for eye-muscle area, fat depth at the 12/13th rib and the rump P8 site, and percentage intramuscular fat, recorded via live ultrasound scanning of Australian Angus cattle. Records on heifers or steers were treated as separate traits from those on bulls. Reduced rank estimates of the genetic covariance matrix were obtained by restricted maximum likelihood, estimating the leading three, four, five, six, seven and all eight principal components and these were contrasted with estimates from pooled bivariate analyses.

Results from analyses fitting five or six genetic principal components agreed closely with estimates from bivariate and eight-variate analyses and literature results. Heritabilities and variances for ‘fatness’ traits measured on heifers or steers were higher than those recorded for bulls, and genetic correlations were less than unity for the same trait measured in different sexes. Eye-muscle area showed little association with the other traits.

Reduced rank estimation decreased computational requirements of multivariate analyses dramatically, in essence corresponding to those of an m-variate analysis for m principal components considered. Five or six principal components appeared to be necessary to model genetic covariances adequately. The first three of these components then explained about 97% of the genetic variation among the eight traits.

A simulation study showed that errors in reduced rank estimates of the genetic covariance matrix were small, once three or more principal components from analyses fitting five or more components were used in constructing the estimates. Similarly, accuracy of genetic evaluation for the eight traits using the first four components was only slightly less than that using all principal components.

Results suggest that reduced rank estimation and prediction is applicable for the eight scan traits considered. The leading three to four principal components sufficed to describe the bulk of genetic variation between animals. However, five or more principal components needed to be considered in estimating covariance matrices and the ‘loadings’ of the original traits to the principal components.

Nutritional depletion and its relationship to respiratory impairment in patients with chronic respiratory failure due to COPD or restrictive thoracic diseases

OBJECTIVE

While malnutrition, especially fat-free mass index (FFMI), is a predictor for mortality in chronic obstructive pulmonary disease (COPD), less information on prevalence and mechanisms is available in patients with chronic respiratory failure (CRF) due to restrictive thoracic diseases (RTD).

DESIGN AND SETTING

Cross-sectional study of patients consecutively admitted to an in-patient primary pulmonary centre.

SUBJECTS

One hundred and thirty-two patients (30% RTD; 70% COPD) with CRF and intermittent non-invasive positive pressure ventilation.

INTERVENTIONS

Malnutrition was quantified by bioelectrical impedance analysis or body mass index (BMI), and its relationship to laboratory, lung function, inspiratory muscle and blood gas parameters and 6-min walking distance (6-MWD) was assessed.

RESULTS

Malnutrition in terms of BMI<20 kg/m(2) occurred in 16.1% of patients with COPD but none of those with RTD. FFMI<17.4 (<15.0 in female patients) kg/m(2) was found in 35.4 and 30.7%, respectively. FFMI was correlated with airway obstruction (sR(aw), r = -0.50; FEV(1)/VC, r = -0.28; P< or = 0.01 each) and lung hyperinflation (intrathoracic gas volume, r = -0.41; total lung capacity (TLC), r = -0.50; P< or = 0.001 each) in COPD, and with lung restriction in RTD (TLC, r=0.40; P=0.011). Furthermore, malnourished patients showed a higher inspiratory load (P (0.1)) and reduced 6-MWD in both groups. In COPD, only hyperinflation and P (0.1) were independently related to FFMI.

CONCLUSIONS

Malnutrition as indicated by low FFMI was similarly prevalent in patients with CRF and COPD or RTD, but inadequately represented by BMI. The correlations between lung function impairments specific for the disease and FFMI emphasized the link between malnutrition and respiratory mechanical load irrespective of its aetiology.