Ictal motor signs and interictal regional cerebral hypometabolism

Early motor manifestations are the main components of focal seizures involving the frontal lobe. We examined the relationship between the initial ictal motor manifestations and interictal abnormalities of cerebral glucose consumption (rCMRGlc) as assessed by PET in 48 consecutive patients with focal seizures of neocortical origin. Group data analysis revealed that patients with predominantly unilateral clonic seizures had a significant contralateral perirolandic hypometabolism and to a lesser degree a contralateral frontomesial hypometabolism. Patients with predominantly focal tonic manifestations showed a hypometabolism within the frontomesial and perirolandic regions that was unilateral in all patients with lateralized tonic seizures. Patients with versive seizures had mainly contralateral metabolic depressions without a consistent regional pattern. Patients with hypermotor seizures had metabolic depressions involving frontomesial, anterior cingulate, perirolandic, and anterior insular/frontal operculum areas. In all patient groups, bilateral and symmetric hypometabolism of the thalamus and cerebellum was observed. We propose that this pattern of distinctly abnormal metabolic brain regions demonstrates not only possible epileptogenic zones but also symptomatogenic brain regions as shown by the associations between clinical manifestations and sets of abnormal brain regions, particularly if epileptogenic zones are in a clinically silent neocortical brain region. The detection and possible differentiation of symptomatogenic and epileptogenic zones might improve the effectiveness of presurgical noninvasive studies.

Increased oxidation of LDL in patients with coronary artery disease is independent from dietary vitamins E and C

There is increasing experimental evidence that oxidation of LDL plays a major role in the pathogenesis of coronary artery disease (CAD). However, results from clinical studies on LDL oxidation and CAD are not consistent. In most studies only single plasma factors of LDL oxidation have been determined. We studied 207 patients who underwent coronary angiography. They were divided into subjects with CAD (n = 137) and those without CAD (n = 70). We determined the susceptibility of LDL to in vitro oxidation (lag phase), potential prooxidative and antioxidative plasma factors (plasma vitamin E, LDL vitamin E, ascorbate, iron, copper, ferritin, and ceruloplasmin), and markers of in vivo LDL oxidation (autoantibodies to malondialdehyde-modified LDL, oxidized LDL, and thiobarbituric acid-reactive substances), plasma lipids and lipoproteins, smoking habits, and other coronary risk factors in both groups. The lag phase was significantly shorter in patients with CAD than in patients without CAD (101 +/- 38.6 versus 119 +/- 40.6 minutes, P < .01). There was no correlation between the lag phase and the other oxidation parameters or the coronary risk factors. In multivariate regression analyses the lag phase remained significant in all tested models. Our data suggest that a short lag phase of LDL oxidation might be an independent risk factor of CAD.

Effect of intra-abdominally induced pressure on the urethral pressure profiles of healthy and incontinent bitches

OBJECTIVE

To determine whether reduced pressure transmission is of importance in the pathophysiologic mechanism of urinary incontinence in bitches.

ANIMALS

20 sexually intact, continent bitches and 21 spayed, incontinent bitches.

PROCEDURE

Urethral pressure profiles before (resting) and after (stressed) insufflation of gas in the abdominal cavity were recorded in bitches under general anesthesia. Differences (stressed minus resting) were calculated for all variables. On the basis of these values, the pressure transmission ratio was determined.

RESULTS

Resting pressure profiles of incontinent bitches indicated significantly (P < 0.05) lower maximal closure pressure (4.5 +/- 3.0 cm of H2O) than did those of continent bitches (11.2 +/- 7.2 cm of H2O). The intra-abdominal pressure increase lead to a shortening of total profile length, which was equal in both groups and caused an increase in maximal urethral pressure. The change in maximal urethral pressure was significantly (P < 0.05) greater in incontinent bitches (12.4 +/- 4.1 cm of H2O) than in continent bitches (8.8 +/- 4.5 cm of H2O). The profile areas and the pressure transmission ratios did not differ significantly (P < 0.05) between the 2 groups.

CONCLUSION

The effect of decreased pressure transmission on the urethra is not a factor in the pathophysiologic mechanism of urinary incontinence attributable to urethral incompetence in bitches.

Quantitative electron-spectroscopic diffraction (ESD) and electron-spectroscopic imaging (ESI) analyses of dentine mineralisation in rat incisors

Primary crystal formations in all hard tissues are, according to our investigations, Ca-phosphate chains composed of nanometer sized particles (dots) which develop along the matrix macromolecules. In circumpulpal dentine the centre-to-centre distances between the dots inside the chains reflect the distances between the crystal nucleating sites ("active sites") along the collagen matrix macromolecule. The centre-to-centre distances at the surface of the mineralised collagen fibrils probably reflect the distances between nucleating sites of noncollagenous proteins attached to collagen. These needle-like chains of dots coalesce in lateral directions to form ribbon-like crystallites. The morphological results are supported by correlated small area diffraction studies in the same regions of dentine. We have found that the first appearing Bragg-reflection has a lattice spacing value of 0.388 nm, which corresponds to the (111) apatite value. For the earliest crystal formations the intensity of the (002) reflection is higher than that of the (300)-reflection. A maximum of the net-signal-intensity ratio of the (002) to (300) Bragg-reflection appears at the mineralisation front. This peak repeats with decreasing height 3 to 5 times with a distance range of about 8-16 microm through the whole dentine zone, which corresponds to the distances of the incremental lines, called "von Ebner lines".

The cDNA sequences of cytochrome c oxidase subunit VIa from carp and rainbow trout suggest the absence of isoforms in fishes

The cDNAs of subunit VIa of cytochrome c oxidase from rainbow trout liver and carp heart are presented, revealing 82% identity of their deduced amino acid sequences. The two cDNAs are evolutionary equally distant from the livertype (VIaL) and heart-type (VIaH) of mammalian subunit VIa. The data suggest that in ectotherm fishes no isoforms of subunit VIa occur, and that the postulated tissue-specific mechanism of thermogenesis in mammals, based on interaction of ATP with subunit VIaH (Frank, V. and Kadenbach, B. (1996) FEBS Lett. 382, 121-124), is absent.

Synergistic effect and possible mechanisms of tumor necrosis factor and cisplatin cytotoxicity under moderate hyperthermia against gastric cancer cells

BACKGROUND

Peritoneal carcinomatosis is a difficult management problem, and intraperitoneal treatment approaches may provide an opportunity to intensify dose and minimize toxicity. The current experiments were conducted to characterize the cytotoxic effects of cisplatin (cDDP), tumor necrosis factor (TNF), and hyperthermia (HT) on a gastric cancer cell line in vitro under conditions achievable with intraperitoneal treatment.

METHODS

Seoul National University gastric cancer cell line (SNU-5), a poorly differentiated gastric cancer cell line, was tested for sensitivity to various doses of cDDP, TNF, or combinations of the two at normothermia (37 degrees C) or HT (42.5 degrees C). The effect of TNF on cellular rates of cDDP accumulation, efflux, and cDDP-DNA adduct formation were evaluated using atomic absorbance spectrometry with Zeemen background correction.

RESULTS

During a 2-h exposure to various doses of cDDP HT, we observed a supraadditive cytotoxicity of SNU-5 with 1 to 50 micrograms/ml of TNF (p2 = 0.0001). In the presence of the three-agent combination (HT, TNF, and cDDP) we observed statistically significant increases in total cellular accumulation of cisplatin (p2 = 0.016); a nonsignificant decrease in cellular efflux of drug (p2 = 0.098); and a 40% increase in persistent cisplatin DNA damage as measured by atomic absorption spectrophotometry (p2 = 0.06). These patterns were specifically not seen with the combinations of cDDP and HT, or cDDP and TNF.

CONCLUSIONS

These data provide the experimental basis for the use of TNF and cDDP with HT in the treatment of gastric cancer and support the investigation of these agents in vivo in the regional treatment of peritoneal carcinomatosis.

HLA markers and prediction of clinical course and outcome in rheumatoid arthritis

OBJECTIVE

To evaluate HLA markers as early prognostic factors for disease severity in rheumatoid arthritis (RA).

METHODS

HLA genotyping was carried out in a retrospective analysis of 66 RA patients and in a prospective study of 55 RA patients and 87 healthy controls using polymerase chain reaction-based methods for HLA-DRB1 specificities, DR4 alleles, and their linked DQB1 alleles, as well as HLA-B27. The clinical course of RA was assessed by clinical and radiologic scores. The impact of HLA markers was evaluated by epidemiologic means in addition to modeling using multiple logistic regression analysis.

RESULTS

Shared epitope-positive (HVR3+) DR4 alleles and the HVR3 amino acid cassette QKRAA were associated with RA in both longstanding (relative risk [RR] 3.34 and 3.19) and recent-onset (RR 2.1 and 2.37) RA. In longstanding RA, radiologic evidence of severe joint destruction (Larsen score > 1.62) was seen more often in HVR3 shared epitope-positive patients than in epitope-negative patients (odds ratio [OR] = 25.67, chi 2 = 13.59, P = 0.0003). Moreover, rank sum analysis of Larsen indices indicated significantly higher ranking for the presence of the RA-associated HVR3 cassettes (QKRAA, QRRAA) when expressed on a DR4 allele (P < 0.0001). In the prospective study, DR4-positive patients had a significantly increased risk (OR = 13.75, P = 0.00083) of developing bony erosions. In addition, HVR3 epitope-positive DR4-positive individuals had significantly higher Larsen indices than did epitope-negative patients (P = 0.0083). In particular, the presence of the HVR3 epitope on DR4 resulted in an increased a posteriori likelihood (0.91) of developing early erosive disease compared with an a priori risk of 0.62. Conversely, the likelihood decreased to a minimum of 0.35 when the HVR3 epitope was absent.

CONCLUSION

While the contribution of HLA typing to establishing the diagnosis of RA is limited, HLA-DR genotyping and DR4 subtype determination provide valuable markers for the prognosis of joint destruction in RA.

Effects of novel and conventional anti-cancer agents on human endothelial permeability: influence of tumour secreted factors

A number of anti-cancer agents have been implicated in vascular toxicity. The effects have been attributed to direct drug toxicity towards endothelium. Little attention has been focussed on the interaction between anticancer drugs, endothelial cells and tumour secreted factors. It is well known that tumours can secrete factors such as vascular permeability factor which do affect endothelial cells and could alter their response to the vascular effects of anticancer drugs. In the present study, we have examined, in vitro, the direct effects of vinblastine (VBL), 5-fluorouracil (5-FU), melphalan (L-PAM) and the novel tubulin inhibitor combretastatin A-1 (CBS) on endothelial permeability under normal and tumour simulated conditions. Monolayers of human umbilical vein endothelial cells (HUVEC) grown on membrane filters were incubated in drug in normal growth medium or medium conditioned by the human melanoma cell line, RPMI-7951 (TCM). VBL caused a rapid increase in permeability during the first 20 minutes, which was maintained for the duration of the experiment (120 minutes). The effect was not altered by TCM or restored to control levels when VBL was replaced by drug-free medium. Similarly, CBS caused a rapid increase in permeability; however, in contrast to VBL, this increase was enhanced by TCM. The changes induced by VBL and CBS were accompanied by contraction of the endothelial F-actin cytoskeleton. Neither L-PAM nor 5-FU altered the permeability of HUVEC monolayers. This study demonstrates that certain anti-cancer agents have a direct effect on endothelial cells, leading to an increase in the permeability of endothelial monolayers. Both VBL and CBS have vascular components in their mode of action which may lead to vascular collapse and tumour necrosis.

[Von Willebrand factor concentrations in blood plasma of Bernese mountain dogs]

Many Bernese Mountain dogs have been found to exhibit an increased hemorrhagic tendency of unknown etiology. Since other bleeding disorders have been excluded by routine tests and Bernese Mountain dogs have been listed to have von Willebrand's disease (vWD), we analyzed the plasma concentration of the von Willebrand Factor (vWF) in 160 Bernese Mountain dogs that were used for breeding in Switzerland in 1992. We also evaluated the suitability of the commercial Asserachrom vWF test kit to quantitate vWF in canine plasma by comparing the plasma vWF determination with validated vWF ELISA test. The vWF plasma concentration in Bernese Mountain dogs ranged from 13% to 162%, with the Asserachrom test kit (normal range 67% to 124%). Similar values were obtained with the research vWF ELISA kit (10% to 166%), and there was a close correlation between the two test methods. In 8 of the 9 Bernese Mountain dogs with initially low vWF concentration (< 60%), the determination was repeated on another sample. Since the values were well within the normal range, a problem with the collection of blood for the first determination is suspected. We conclude that vWD does not appear to be a clinical issue in Bernese Mountain dogs in Switzerland and is, therefore, not likely to be the cause of the observed bleeding tendency. The commercially available Asserachrom vWF test kit seems suitable for the determination of canine vWF plasma concentrations. It is recommended that low vWF values will be confirmed by the determination in second samples.

[Urinary incontinence in castrated bitches. 2. Diagnosis and treatment]

Urinary incontinence due to spaying is caused by a sphincter incompetence of the urethra. In practice the diagnosis is established by ruling out other causes of incontinence such as neurological disease, bacterial cystitis, urinary tract malformation, iatrogenic ureterovaginal fistula and neoplasia of the urinary tract. An accurate diagnosis of urethral sphincter incompetence is made by urethral pressure profilometry. A urethral closure pressure of 7.4 cm H2O allowed the differentiation of bitches with urinary incontinence, due to spaying, from healthy control dogs with a diagnostic accuracy of 91%. For therapy alpha-adrenergic drugs (Ephedrine or Phenylpropanolamine) are recommended, which result in continence in 74% and improvement in 24% of incontinent patients. In the absence of response estrogens may be used. If the medical therapy fails to achieve urinary continence, the endoscopic injection of collagen into the submucosa of the proximal urethra can be performed. This is a simple and minimally invasive procedure. It rarely leads to complications and may be repeated when necessary. The method is successful in 75% of cases.

Surgical treatment of male dogs with urinary incontinence due to urethral sphincter mechanism incompetence

A modified technique for fixation of the deferent ducts to the abdominal wall as a therapy for urinary incontinence caused by urethral sphincter mechanism incompetence (USMI) in male dogs is described, and the results in seven dogs are reported. The goal of this treatment was to achieve an effect similar to colposuspension in female dogs with USMI. An increase in urethral length of an average of 28 mm was obtained (range, 5 to 50 mm, measured radiographically). Preoperatively, the neck of the bladder was located intrapelvically in five of seven dogs. Postoperatively, the neck of the bladder was located intra-abdominally, near the caudo-ventral abdominal wall, in all dogs. After a follow-up period of 12 to 49 months, the response to surgery, based on lack of or decrease of incontinence, was excellent in three dogs, good in another three, and poor in one dog.

A molecular switch in cytochrome C oxidase turns on thermogenesis in heart at low work load

We describe a new mechanism of respiratory control by ATP on cytochrome c oxidase, which contrasts with the well known respiratory control of the electron transfer chain in mitochondria by ADP/ATP ratios. It is well established that high ADP/ATP ratios stimulate respiration and thus the synthesis of ATP in mitochondria, according to the energy requirements of the cell. Herein we describe the direct stimulation by high ATP/ADP-ratios of bovine heart (but not liver) cytochrome c oxidase activity in reconstituted vesicles. Under these same conditions it has already been shown that ATP decreases the H+/e- stoichiometry of cytochrome oxidase. Thus the observed effect of high ATP on cytochrome c oxidase would be expected to lead to partial uncoupling of energy transduction in mitochondria and to stimulation of thermogenesis.

Cerebellar hypometabolism in focal epilepsy is related to age of onset and drug intoxication

PURPOSE

We wished to investigate the cerebellar depression of regional cerebral glucose metabolism (rCMRGlu) in patients with focal epilepsy.

METHOD

In 170 consecutive patients with medically refractory, focal epilepsy the rCMRGlu was measured in cerebellum and brain.

RESULTS

rCMRGlu was markedly decreased in both cerebellar hemispheres and slightly in brain. The cerebellum to brain rCMRGlu ratio was significantly decreased in patients with seizure manifestation in infancy, but was normal due to a progressive decrease in brain rCMRGlu in later age. A subgroup of patients with focal epilepsy involving the frontal lobe had a reduced cerebellum/brain rCMRGlu ratio, whereas in patients with mesiotemporal lobe epilepsy (MTLE), the rCMRGlu was decreased to the same degree in cerebellum and brain. The difference in the cerebellum/brain rCMRGlu ratio between the two groups was accounted for by the younger age of the patients with focal epilepsy involving the frontal lobe, however. In another subgroup of patients with a documented history of critical drug intoxications, the cerebellar rCMRGlu was severely decreased, resulting in a significantly reduced cerebellum/brain rCMRGlu ratio.

CONCLUSION

Our retrospective study suggests that the cerebellum is particularly vulnerable in infancy to ongoing epileptic activity and high dosage of antiepileptic drugs (AEDs).

Mucolipidosis type II in a domestic shorthair cat

A seven-month-old, female domestic shorthair cat was presented to the Veterinary Teaching Hospital, University of Zurich, with abnormal facial features, retarded growth and progressive hindlimb paresis. On physical examination the cat had a flat, broad face with hypertelorism, frontal bossing, small ears and thickened upper and lower eyelids. The corneas of both eyes were clear and the pupils were dilated. The skin was generally thickened, most prominently on the dorsal aspect of the neck. Radiography of the entire skeleton revealed a severely deformed spinal column, bilateral hip luxation with hip dysplasia, an abnormally shaped skull and generalised decreased bone opacity. The clinical features and radiographic changes were suggestive of mucopolysaccharidosis. The toluidine blue spot test on a urine sample, however, was negative for glycosaminoglycans. Further biochemical investigations revealed a deficiency of the enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase, EC 2.7.8.17) in peripheral leukocytes and an elevation of many lysosomal enzymes in the serum of the cat which is diagnostic for mucolipidosis type II. Histology and electron microscopy of different tissues are briefly summarised. The findings of this cat, the first reported case of mucolipidosis type II are compared with other similar storage diseases described in the cat.

Effect of nitro-L-arginine on blood flow, oxygenation and the activity of hypoxic cell cytotoxins in murine tumours

This study was an investigation into the ability of nitro-L-arginine to change blood flow, oxygenation status and the activity of hypoxic cell cytotoxic agents in two different transplanted murine tumours. The tumour models were the C3H mammary carcinoma grown in the feet of female CDF1 mice and the SaF grown on the backs of CBA mice. Treatments were carried out in restrained non-anaesthetised animals when tumours were about 100 to 200 mm3 in size. Blood flow was monitored using laser Doppler flowmetry; oxygen partial pressure (pO2) distributions were obtained with an Eppendorf oxygen electrode; and response to treatment with hyperthermia (43.5 degrees C; 30 min) and RB6145 (250 mg kg-1;i.p.) assessed using a tumour growth delay assay. Nitro-L-arginine (10 mg kg-1; i.v.) significantly reduced blood flow by around 40-60% within 15 min after injection in C3H tumour and by 30 min in the SaF. However, nitro-L-arginine had absolutely no effect on tumour pO2 measured at the time of maximal blood flow reduction in both tumour types. It also failed to enhance the response of the C3H tumour to heat, but did produce a small yet significant increase in the response of the SaF tumour to RB6145.

Microregional blood flow in murine and human tumours assessed using laser Doppler microprobes

A multichannel laser Doppler system has been used to measure microregional fluctuations in perfusion in the HT29 human tumour xenograft and in patients with advanced malignant disease. A comparison is made with previously obtained data for the SaF, a transplantable murine tumour. The 300 microns diameter probes recorded fluctuations in erythrocyte flux in tumour microregions with an estimated volume of 10(-2) mm3. Of the 66 human tumour microregions sampled, 26% showed a change in erythrocyte flux by a factor of 2 or more over the 60 min measurement period, compared with 37% of HT29 and 48% of SaF microregions. In each of the studies more than 50% of changes were completed within 20 min, although slower changes were more common in the human tumours than in the experimental systems. Within the 1 h monitoring period at least 30% of the changes were reversed (human tumours 30%, HT29 45%, SaF 31%). These findings demonstrate that microregional changes in erythrocyte flux, consistent with transient, perfusion-driven changes in oxygenation, are a feature of human malignancies as well as experimental transplanted tumours.

Changes in coagulation and permeability properties of human endothelial cells in vitro induced by TNF-alpha or 5,6 MeXAA

5,6 dimethyl xanthenone acetic acid (5,6 MeXAA), an analogue of flavone acetic acid (FAA), has been shown to be more active against murine tumours than FAA. As both drugs have a vascular component in their mechanism of action similar to that observed for TNF-alpha, we have studied the effects of 5,6 MeXAA alone and in combination with TNF-alpha on endothelial function in vitro. The changes induced by the drugs on procoagulant activity and permeability were determined under tumour-simulated conditions of low oxygen tension and the presence of tumour-secreted factors. Procoagulant activity was assayed by measuring the time taken for human umbilical vein endothelial cells (HUVECs) to clot normal human plasma, increased activity resulting in reduced clotting times. HUVECs incubated under aerobic conditions were more sensitive to TNF-alpha than cells incubated at < or = 0.2% oxygen. Culture medium conditioned by the human breast adenocarcinoma cell line MDA-MB-231 strongly upregulated procoagulant activity under both aerobic and hypoxic conditions; clotting times were further reduced by TNF-alpha. Both 5,6 MeXAA and FAA potentiated the effect of TNF-alpha on normal hypoxic endothelial cells; however, under all other conditions, neither drug in combination with TNF-alpha upregulated clotting activity. The presence of tumour-secreted factors had a far greater effect on upregulating procoagulant activity than did oxygen tension. In contrast to procoagulant activity, permeability was insensitive to TNF-alpha and low concentrations of 5,6 MeXAA also caused no change in permeability.

Morphology-dependent resonances of a microsphere-optical fiber system

Morphology-dependent resonances of microspheres sitting upon an index-matched single-mode fiber half-coupler are excited by a tunable 753-nm distributed-feedback laser. Resonance peaks in the scattering spectra and associated dips in the transmission spectra for the TE and TM modes are observed. We present a new model that describes this interaction in terms of the fiber-sphere coupling coefficient and the microsphere's intrinsic quality factor Q(0). This model enables us to obtain expressions for the finesse and the Q factor of the composite particle-fiber system, the resonance width, and the depth of the dips measured in the transmission spectra. Our model shows that index matching improves the coupling efficiency by more than a factor of 2 compared with that of a non-index-matched system.

Topography of interictal glucose hypometabolism in unilateral mesiotemporal epilepsy

We mapped the regional cerebral glucose metabolism (rCMRGlu) in 20 patients suffering from medically refractory focal epilepsy of either left or right mesiotemporal origin (mTLE) during resting wakefulness. After temporal lobectomy, histology demonstrated hippocampal sclerosis in 18 patients. Pixel-by-pixel comparisons with healthy control subjects showed significant (p < 0.001) depressions of the mean rCMRGlu ipsilateral to the epileptic focus in the mesiotemporal region, including the hippocampus and the parahippocampal gyrus and middle temporal gyrus. Additional remote rCMRGlu depressions occurred bilaterally in the fronto-orbital cortex and ipsilaterally in the posterior insula and the thalamus. Patients with left-sided mTLE had additional rCMRGlu depressions in the left inferior frontal gyrus (Broca's region) and superior temporal gyrus at the parietotemporal junction, whereas corresponding rCMRGlu depressions were not present in patients with right mTLE. Neuropsychological testing showed impaired verbal fluency, verbal intelligence, and verbal memory in the left mTLE patients. Correlations of the specific mean rCMRGlu depressions and the neuropsychological deficits suggest that impaired language functions in patients with left mTLE could result from functional changes beyond the temporal lobe.

Uterine serosal inclusion cysts in a bitch

A six-year-old, pluriparous German shepherd dog bitch was presented with an abnormal vaginal discharge of several weeks' duration. Clinical signs and radiographic and ultrasonographic findings supported an initial diagnosis of segmental cystic endometrial hyperplasia, and ovariohysterectomy was performed. Macroscopically, the uterus appeared normal except for one large and several smaller cysts attached to its antimesometrial side. These cysts were restricted to a small area of the left uterine horn. The histological diagnosis was serosal inclusion cysts. The clinical findings, gross pathology and histopathology are described and discussed.

Thalamic metbolism and corticospinal tract integrity determine motor recovery in stroke

We studied the role of remote metabolic depressions and pyramidal tract involvement regarding motor recovery following a first hemiparetic ischemic stroke. In 23 patients the regional cerebral glucose metabolism (rCMRGlu) was measured with positron emission tomography and the location and spatial extent of the stroke lesions were assessed by magnetic resonance imaging. Motor impairment during the acute and chronic stages (4 weeks after stroke) was determined by a motor score and recordings of magnetic evoked motor potentials. Twelve patients recovered significantly, whereas 11 patients retained a disabling hemiparesis. In contrast to patients with good motor recovery, rCMRGlu was severely depressed in the thalamus on the lesion side in patients with poor motor recovery. This patient group also showed more severe damage to the pyramidal tract on magnetic resonance images and a more pronounced reduction of the magnetic evoked motor potential amplitude. Neither the size of the stroke lesions nor the spatial extent of the lesional and remote rCMRGlu depressions outside the thalamus correlated with the thalamic hypometabolism and the improvement of the motor score. We conclude that preservation both of parts of the pyramidal tract and of the thalamic circuitry is a major determinant for the quality of hand motor recovery following acute brain ischemia in the adult.

Treatment of urinary incontinence in bitches by endoscopic injection of glutaraldehyde cross-linked collagen

Thirty-two spayed bitches with urinary incontinence due to urethral sphincter incompetence, non-responsive to phenylpropanolamine administration, were treated by urethral submucosal injection of glutaraldehyde cross-linked collagen. Urinary incontinence resolved after a single injection in 19 of the bitches. Additional medication with phenylpropanolamine was necessary in five of these dogs, however. Of the 13 bitches that remained incontinent, the injections were repeated in nine. This resulted in a return to continence in five dogs, although two of these required additional medication for complete continence. The cure rate due to collagen injections alone is 53 per cent (17 of the 32 cases). A total of 41 injections were performed and no post-operative complications were observed.

Neurological impairment and recovery in Wilson's disease: evidence from PET and MRI

We studied the relationship of regional cerebral glucose consumption (rCMRGlc) and striatal dopamine D2 receptor binding as assessed with positron emission tomography (PET) with the structural abnormalities of the brain in magnetic resonance images (MR), and the degree of neurological impairment in 18 patients with Wilson's disease (WD). The rCMRGlc was determined in the basal ganglia, the thalamus, the cerebral cortex, and the cerebellar hemispheres. The severity of neurological signs, defined by semiquantitative motor impairment scores, correlated highly (r = -0.80) with the reduction of striatal rCMRGlc. Clinical scores, striatal rCMRGlc, and the degree of MRI abnormalities showed no correlation with different indices of dopamine D2 receptor binding. Sequential PET measurements in three patients during treatment with chelating agents revealed a moderate increase of striatal rCMRGlc (in two patients) and a moderate to marked increase of striatal D2 receptor binding (in three patients) in association with clinical improvement. Our data suggest that the rCMRGlc represents a sensitive and objective measure for assessing and monitoring striatal and extrastriatal involvement in WD. The lack of correlation between the dopamine D2 receptor binding and striatal rCMRGlc and structural abnormalities may be explained by the wide spectrum of clinical manifestations and different responses to treatment in WD patients.

Orthotopic implantation of inflamed synovial tissue from RA patients induces a characteristic arthritis in immunodeficient (SCID) mice

The objective of this work was to study in more detail the human/murine SCID arthritis model with special emphasis on characteristic features initiated by rheumatoid arthritis (RA) synovial membrane (SM) as compared to appropriate control tissues. Small tissue samples from RA-SM, healthy lymph node, healthy SM, and granulomatous tissue of human origin were implanted into the left knee joint of mice with severe combined immunodeficiency (SCID), and the joints were analysed histologically after 7 days. In addition, a time course study, including non-invasive monitoring by serological parameters (human IgM, IgG, and IL-6) and Tc-99m-scintigraphy, was performed for up to 4 weeks on RA-SM recipients. All tissue implants induced transient exudative joint inflammation while RA-SM initiated a characteristic arthritis with pannus tissue of high cellular density, erosion, multinuclear giant cells, lining cell hyperplasia, fibroblast-like cell layers, chondroideal metaplasia, and fibrin deposits. Significantly elevated levels of human immunoglobulin and characteristic signs of chronic inflammation persisted for more than 4 weeks. We conclude that the hu/mu SCID arthritis with RA-SM implants comprises features of non-specific inflammation which is also transiently seen with control tissues but develops characteristic features of chronic RA-like synovitis thereafter.

Spontaneous mucolipidosis in a cat: an animal model of human I-cell disease

A 7-month-old female cat was seen for abnormal facial features and abnormality of gait. Facial dysmorphism, large paws in relation to body size, dysostosis multiplex, and poor growth were noted, and mucopolysaccharidosis was suspected. A negative urine test for sulfated glycosaminoglycans and extreme stiffness of skin indicated a mucolipidosis hitherto unknown in animals. Deficiency of UDP-N-acetylglucosamine: lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase, EC 2.7.8.17) activity was demonstrated in leukocytes and cultured fibroblasts, which had the appearance of inclusion cells (I-cells). Activities of a set of lysosomal hydrolases were abnormally low in fibroblasts and excessive in blood plasma. Postmortem morphology revealed lysosomal inclusions predominantly in fibroblasts but also in endothelial cells and chondrocytes, i.e., in cells of mesenchymal origin. Storage lysosomes contained oligosaccharides, mucopolysaccharides, and lipids. Tissues most affected were bones, cartilage, skin, and other connective tissues such as those in heart valves, aortic wall, and vocal cords. Parenchymal cells of liver and kidney were unaffected, as was skeletal muscle. Only a few of the cerebral cortical neurons had lipid inclusions; in sciatic nerve some axons were affected, but other peripheral nerves were normal. There were striking clinical, biochemical, and morphologic similarities between the disorder in this cat and the human I-cell disease.

Excitation of resonances of microspheres on an optical fiber

Morphology-dependent resonances (MDR's) of solid microspheres are excited by using an optical fiber coupler. The narrowest measured MDR linewidths are limited by the excitation laser linewidth (<0.025 nm). Only MDR's, with an on-resonance to off-resonance intensity ratio of 10(4), contribute to scattering. The intensity of various resonance orders is understood by the localization principle and the recently developed generalized Lorentz-Mie theory. The microsphere fiber system has potential for becoming a building block in dispersive microphotonics. The basic physics underlying our approach may be considered a harbinger for the coupling of active photonic microstructures such as microdisk lasers.

Aerosol particle microphotography and glare-spot absorption spectroscopy

The relative intensities of glare spots in the image of an electrodynamically trapped aerosol droplet are measured experimentally with an aerosol particle microscope and calculated theoretically. The theoretical calculations are in good agreement with these experiments and indicate that the intensities of these spots are extremely sensitive to the imaginary part of the refractive index. Experimentally, we obtain the molecular absorption spectrum of an impurity within a droplet by recording the spectrum of an individual glare spot produced by broadband illumination.

Sexual health education interventions for young people: a methodological review

OBJECTIVES

To locate reports of sexual health education interventions for young people, assess the methodological quality of evaluations, identify the subgroup with a methodologically sound design, and assess the evidence with respect to the effectiveness of different approaches to promoting young people's sexual health.

DESIGN

Survey of reports in English by means of electronic databases and hand searches for relevant studies conducted in the developed world since 1982. Papers were reviewed for eight methodological qualities. The evidence on effectiveness generated by studies meeting four core criteria was assessed. Judgments on effectiveness by reviewers and authors were compared. PAPERS: 270 papers reporting sexual health interventions.

MAIN OUTCOME MEASURE

The methodological quality of evaluations.

RESULTS

73 reports of evaluations of sexual health interventions examining the effectiveness of these interventions in changing knowledge, attitudes, or behavioural outcomes were identified, of which 65 were separate outcome evaluations. Of these studies, 45 (69%) lacked random control groups, 44 (68%) failed to present preintervention and 38 (59%) postintervention data, and 26 (40%) omitted to discuss the relevance of loss of data caused by drop outs. Only 12 (18%) of the 65 outcome evaluations were judged to be methodologically sound. Academic reviewers were more likely than authors to judge studies as unclear because of design faults. Only two of the sound evaluations recorded interventions which were effective in showing an impact on young people's sexual behaviour.

CONCLUSIONS

The design of evaluations in sexual health intervention needs to be improved so that reliable evidence of the effectiveness of different approaches to promoting young people's sexual health may be generated.

Changes in cognitive performance in children with spastic diplegic cerebral palsy following selective dorsal rhizotomy

Children with cerebral palsy who receive selective dorsal rhizotomy (SDR) for treatment of spasticity may show suprasegmental changes in upper limb function and control of speech musculature. Anecdotal reports suggest that supra-segmental effects may extend to cognitive functions such as attention and language. This study examined the performance of 16 children with spastic diplegic cerebral palsy on tests of visual attention and other cognitive functions 1 day prior to and 6 months following SDR. Children undergoing SDR were compared with 9 children with spastic diplegia, matched for severity of cerebral palsy and amount of therapy, who did not receive SDR, and 24 age- and sex-matched normal children tested at initial and 6-month follow-up sessions. Children with cerebral palsy treated with SDR showed disproportionately greater improvement in specific attentional and cognitive operations than either of the other groups. These results document cognitive changes following SDR which heretofore were reportedly anecdotally. This improvement may be due to improved mood, reduced physical discomfort, increased therapeutic intervention, or possible cortical effects of SDR.

Structural relationship between the primary crystal formations and the matrix macromolecules in different hard tissues. Discussion of a general principle

For many years we have investigated the earliest crystal formations of different developing hard tissues (matrix vesicle, bone, dentine, enamel, etc.) by different electron microscopic measurements. It was observed that primarily Ca-phosphate (apatite) "chains," composed of nanometer sized particles (dots, islands), exist, which coalesce rapidly to needles. For the mineralization of collagen (e.g., bone, dentine) the center to center distances between the dots in the mineral chains represent the distances between nucleating sites, so-called "active sites" of collagen which bind primarily Ca for a subsequent nucleation. For the mineralization of noncollagen macromolecules (e.g., enamel) the same principle of mineral nucleation at such "active sites" exists being represented indirectly by corresponding center to center distances between the dots in the mineral chains.

Investigation of the early mineralisation on collagen in dentine of rat incisors by quantitative electron spectroscopic diffraction (ESD)

The earliest crystallites in dentine appear as chains of "dots" in ultra-thin sections viewed by transmission electron microscopy. These dots rapidly coalesce along the longitudinal directions of the collagen microfibrils to form needle-like structures that coalesce preferentially in lateral directions to form ribbon-like or plate-like crystallites. This morphological interpretation is supported by line-scans of the corresponding zero-loss filtered electron spectroscopic diffraction patterns, which demonstrate the crystalline structure of the dentine mineral (apatite). The intensity ratio of the Debye-Scherrer rings of the characteristic Bragg-reflections (002 to 300, together with 1 or 2 unresolved reflections) shows a maximum in the region of early chain-like and needle-like crystallites, decreasing with maturation of the dentine mineral to the ribbon-plate-like crystallites. Detailed investigations using line-scans of the zero-loss filtered electron spectroscopic diffraction patterns through the dentine zone show that the intensity ratio found near the mineralisation front is repeated 3-5 times at distances of about 10-20 microns. This may represent a circadian pattern of mineralisation corresponding to light microscopically visible incremental lines in dentine.

Neutralizing monoclonal antibodies define two different functional sites in human interleukin-4

Human interleukin-4 (IL-4) is a small four-helix-bundle protein which is essential for organizing defense reactions against macroparasites, in particular helminths. Human IL-4 also appears to exert a pathophysiological role during various IgE-mediated allergic diseases. Seven different monoclonal antibodies neutralizing the activity of human IL-4 were studied in order to identify functionally important epitopes. A collection of 41 purified IL-4 variants was used to analyse how defined amino acid replacements affect binding affinity for each individual mAb. Specific amino acid positions could be assigned to four different epitopes. mAbs recognizing epitopes on helix A and/or C interfered with IL-4 receptor binding and thus inhibited IL-4 function. However, other mAbs also inhibiting IL-4 function recognized an epitope on helix D of IL-4 and did not inhibit IL-4 binding to the receptor protein. One mAb, recognizing N-terminal and C-terminal residues, partially competed for binding to the receptor. The results of these mAb epitope analyses confirm and extend previous data on the functional consequences of the amino acid replacements which showed that amino acid residues in helices A and C of IL-4 provide a binding site for the cloned IL-4 receptor and that a signalling site in helix D interacts with a further receptor protein.

Preparing children for a surgical experience

1. Little research has been conducted on the specific fears of children undergoing surgery. One study reported that the events most remembered about the surgical experience were riding to the operating room, receiving injections, waking up in pain, and not being allowed to eat or drink. The most feared events were injections and the anesthesia mask. 2. Many hospitals have developed formal and informal orientation programs for preparing children for surgery. Special orientation days with themes may be offered. Films/videos, slide presentations, coloring books, photograph albums, puppet shows, and tours often are used to introduce the child to the surgical environment. A visit to the operating room may be a part of the program. In some cases, play therapy in a mock operating room is used. 3. A warm, open, honest environment is crucially important. There should be a willingness to discuss the child's ideas, fears, and misconceptions concerning their perioperative experience. In addition, children should be given the opportunity to learn about their body, the health care profession, and the surgical setting.

Substance use among the mentally ill: prevalence, reasons for use, and effects on illness

Substance use among a random sample of mentally ill, community-based patients was examined. Current use was found to have declined substantially from a high lifetime prevalence, and a family history of substance abuse was associated with moderate to heavy use. No association was found between heavy substance use and elevated psychopathology, hospitalization, or medication noncompliance. Hospital admissions and some symptoms were less prevalent among users preferring marijuana.

Two distinct functional sites of human interleukin 4 are identified by variants impaired in either receptor binding or receptor activation

Interleukin 4 (IL-4) exerts a decisive role in the coordination of protective immune responses against parasites, particularly helminths. A disregulation of IL-4 function is possibly involved in the genesis of allergic disease states. The search for important amino acid residues in human IL-4 by mutational analysis of charged invariant amino acid positions identified two distinct functional sites in the 4-helix-bundle protein. Site 1 was marked by amino acid substitutions of the glutamic acid at position 9 in helix A and arginine at position 88 in helix C. Exchanges at both positions led to IL-4 variants deficient in binding to the extracellular domain of the IL-4 receptor (IL-4R(ex)). In parallel, up to 1000-fold increased concentrations of this type of variant were required to induce T-cell proliferation and B-cell CD23 expression. Site 2 was marked by amino acid exchanges in helix D at positions 121, 124 and 125 (arginine, tyrosine and serine respectively in the wild-type). IL-4 variants affected at site 2 exhibited partial agonist activity during T-cell proliferation; however, they still bound with high affinity to IL-4R(ex). [The generation of an IL-4 antagonist by replacing tyrosine 124 with aspartic acid has been described before by Kruse et al. (1992) (EMBO J., 11, 3237-3244)]. These findings indicate that IL-4 functions by binding IL-4R(ex) via site 1 which is constituted by residues on helices A and C.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanisms of ventricular arrhythmia during amitriptyline toxicity

The ventricular tachycardia (VT) caused by high-dose tricyclic antidepressants has been hypothesized to be due to a quinidinelike effect with generation of repolarization abnormalities and afterdepolarizations. To test this hypothesis further, we infused amitriptyline in a graded fashion (0.5-1 mg/kg/min) in 23 chloralose-anesthetized dogs during endocardial monophasic action potential (AP) recording and continuous hemodynamic monitoring. Three groups of dogs were studied: group A (n = 5), crushed sinus node and fixed atrial pacing at 100 beats/min; group B (n = 12), crushed sinus node and fixed atrial pace plus intermittent accelerated pacing to mimic group C; and group C (n = 6) intact sinus node and unimpeded sinus tachycardia. Amitriptyline infusion induced VT in no (0 of 5) group A dogs, all (12 of 12) group B dogs during accelerated pacing, and 83% (5 of 6) of group C dogs. Dogs with VT had significantly higher heart rates (HR 184.8 +/- 39.3 beats/min) as compared with dogs without VT (115.2 +/- 12.5 beats/min, p = 0.0015). There was a strong positive correlation between the last RR coupling interval to the first VT interval (r = 0.85; p = 0.0033). Amitriptyline infusion caused rate-dependent QRS prolongation in each group, especially group C (p < 0.001). Action potential duration at 50% and 90% of repolarization (APD50, APD90) showed a biphasic response with progressive shortening followed by prolongation as amitriptyline serum concentrations increased. Afterdepolarizations were not detected from any monophasic AP recording, even in dogs with VT.(ABSTRACT TRUNCATED AT 250 WORDS)

Reproducibility of urethral pressure profiles in clinically normal sexually intact female dogs by use of microtransducer catheters

Urethral pressures profiles (UPP) obtained by use of microtransducer catheters were determined in 8 anestrous sexually intact female Beagles during general anesthesia. A UPP study consisted of 3 consecutive recordings, and 4 UPP studies were repeated at an interval of 5 days in each dog. Maximal urethral pressure (cm of H2O), bladder pressure (cm of H2O), and anatomic urethral length (cm) were recorded. Maximal urethral closure pressure (cm of H2O) was calculated. Mean +/- SD (for all measurements) maximal urethral closure pressure was 12.8 +/- 5.6 cm of H2O (range, 2.4 to 25.2 cm of H2O). Maximal urethral closure pressure was significantly (P < 0.05) decreased during the first recording period (11.4 +/- 5.8 cm of H2O), compared with the second (13.0 +/- 5.2 cm of H2O) or third (14.1 +/- 5.7 cm of H2O) recording periods within a UPP study (3 consecutive recordings). Mean maximal difference in urethral closure pressure during a single UPP study was 4.8 +/- 2.4 cm of H2O. Significant difference in maximal urethral closure pressure was not observed between studies. Mean (for all measurements) anatomic urethral length was 6.2 +/- 0.9 cm (4.1 to 7.8 cm). Anatomic urethral length was significantly (P < 0.05) less during the first recording period (6.1 +/- 0.9 cm), compared with values for the second and third periods (6.3 +/- 0.9 cm, 6.4 +/- 0.9 cm respectively). Anatomic urethral length for time 3 was significantly (P < 0.05) less than the value for time 1 (5.8 +/- 0.7 cm vs 6.6 +/- 0.8 cm).(ABSTRACT TRUNCATED AT 250 WORDS)

Photon-correlation spectroscopy for small spherical inclusions in a micrometer-sized electrodynamically levitated droplet

Micrometer-sized droplets of saturated sodium chloride solution were captured in an electrodynamic levitator and maintained at constant diameter for several days at a time. Both pure droplets and droplets containing 0.5-microm subparticles (guests) were studied by means of 90-deg scattering of polarized laser light. Analysis of the correlation function for the intensity of the scattered light gave characteristic decay times of &~9 ms, which has a good correspondence with the physical parameters of the solution and the size of the subparticles. Longer characteristic times are measures of morphological features of the electromagnetic field intensity in the host particles. A new phenomenon was observed when the exit polarizer was crossed to the input polarization. Scattered light corresponding to light from the guest particles could only be visualized from a shell near the exterior of the sphere and not from the interior of the host droplet.

Morphology and stereology of the female canine urethra correlated with the urethral pressure profile

Perfusion-fixed urethrae of five sexually intact nulliparous female beagles in anestrus, between 2 and 3 years of age, were morphologically and morphometrically investigated. Absolute and relative volumes of different tissue components were stereologically estimated per urethral quarter. A discrete smooth muscle sphincter could neither be identified in the bladder neck nor in the urethra. However, the circularly arranged smooth muscle fibers in the proximal half of the urethra were regarded as being capable of sphincteric function. The connective tissue, composed of collagenous and longitudinally orientated numerous elastic fibers, accounted for the most predominant constituent. It comprised 77.3 to 78.2% of the total volume in the proximal three urethral quarters. The vascular plexus was most prominently developed in the proximal two urethral quarters, and its relative and absolute volumes significantly exceeded those of the third quarter. The discovered direct connections between small arteries and the sinusoids of the vascular plexus emphasize its importance as a major contributory component to urinary continence. The striated musculus urethralis was essentially confined to the distal half of the urethra and most strongly developed in the fourth quarter, where it surrounded the urethra transversely at its ventral and lateral aspects. The caudal muscle fibers continued dorsally to the vagina. A transitional epithelium bounded the urethral lumen. Its superficial cell layer progressively flattened towards the external urethral orifice, changing into a stratified squamous lining as also seen in the vestibulum. Recorded pressures, or pressure changes, could neither be correlated with volumes nor with morphology of particular tissue elements in the different urethral quarters.