Sj?gren syndrome: comparison of assessments with MR sialography and conventional sialography

We investigated the effects of genes controlling melanism on levels and patterns of activity, potential nonvisual components of fitness, of adult Mediterranean flour moths, Ephestia kuehniella Zeller (1879). Six genotypes of two melanic strains (Ala nigra and black) were used. We monitored continuously the walking or flight activity of 45 mated females per genotype during the third night of their lives, using automatic electrostatic techniques to carry out the measurements. Although there was high individual variation within genotypes, bb (melanic) females were more active than the two nonmelanic genotypes of the black strain (b+, ++) because they tended to show more bouts of activity. There were no differences in the average length of these bouts, or in the timing of initial and final activity. Overall, the females of the black strain were significantly more active than the females of the Ala nigra strain. The results are discussed in the context of the evolution of melanism in moths. Copyright 1998 The Association for the Study of Animal Behaviour     

Aetiological and histological classification of sialadenitis

Minisatellites are composed of tandem repetitive DNA sequences and are present at many positions in the human genome. They frequently mutate to new length alleles in the germline, by complex and incompletely understood recombination mechanisms which may operate during meiosis. In several minisatellites the mutation events are restricted to one end of the repeat array, indicating a possible association with elements that act in cis. Mutant alleles do not show exchange of flanking regions. To construct a model system suitable for further investigations of the mutation process, we have integrated the human minisatellite MS32, flanked by synthetic markers, in the vicinity of a meiotic recombination hot spot upstream of the LEU2 locus in the yeast Saccharomyces cerevisiae. Here we provide direct evidence for a meiotic origin of MS32 mutations. Mutation events were polarised towards both ends of the minisatellite and varied from simple duplications and deletions to complex intra- and interallelic events. Interallelic events were frequently accompanied by exchange of regions flanking the minisatellite. The results also support the notion that cis-acting elements are involved in the mutational process. The fact that MS32 mutant structures are similar in yeast and human shows that meiotic recombination plays a crucial role in both organisms and emphasises the usefulness of yeast strains harbouring minisatellites as a model system for the study of minisatellite mutation.     

Bone scintigraphy in the detection of chronic recurrent multifocal osteomyelitis

In this study, we describe the importance of the whole-body bone scan in diagnosing the multifocality of chronic recurrent multifocal osteomyelitis (CRMO) and in distinguishing it from unifocal acute hematogenous osteomyelitis. MATERIALS: The medical records and two-phase, whole-body bone scans of 14 patients (mean age 10.5 yr) with the diagnosis of CRMO, were retrospectively reviewed. The diagnosis of CRMO was based on bone biopsy in 9 patients and clinical course/laboratory findings in 5. Bone scans were evaluated for geographic and anatomic locations of their lesions. Correlative radiographs of areas of abnormal uptake were performed to assess the radiographic appearance of the lesions. RESULTS: The presentation of the disease was localized to one painful, tender and swollen periarticular site 86% of the time. The number of lesions detected by bone scan varied from 1-18 (mean 6). Most lesions were metaphyseal, proximal or distal tibial lesions. Purely sclerotic or mixed (sclerosis and lysis) lesions were found on radiographs. Bilateral lesions were seen in 64% of patients. Biopsies were negative for organisms in all patients and exhibited subacute or chronic histologic changes in most instances. Complications of chronic hyperemia included marked overgrowth (5), diffuse demineralization (1), angular deformity (1) and length discrepancy (1). CONCLUSION: The identification of the multifocal configuration of the disease process by two-phase (soft-tissue and delayed) whole-body bone scintigraphy results in appropriate diagnosis and therapy of CRMO. Additional sites for possible bone biopsy become apparent for exclusion of other diagnoses. Supportive (nonsteroidal, anti-inflammatory medication) instead of antimicrobial therapy can be initiated with significant cost savings.     

An experimental study of PAH clearance in chronic unilateral and completely obstructed kidney

The following experiment was performed to estimate PAH clearance of chronic unilateral and completely obstructed kidney and to explore its change during obstruction period. Thirty adult male mongrel dogs were used. Unilateral complete ureteral obstruction was made by ligation of the left ureter proximal to the bladder. After 3, 5, 10, 20 and 40 days of obstruction, an experiment was performed. Under laparotomy, the left kidney was exposed and polyethylene catheter was inserted into the renal pelvis. Intrapelvic pressure was monitored by pressure transducer. In a condition that PAH (p-aminohippurate) was constantly infused intravenously, intrapelvic urine of the obstructed kidney was exchanged for physiological saline. After the exchange, intrapelvic PAH concentration was measured at hourly intervals for 4 hours. At each midpoint of the measurements, plasma PAH concentration was measured. At the end of the experiment, the obstructed kidney was resected and pelvic capacity was measured. PAH of the obstructed pelvis increased at hourly intervals after the exchange. The result showed that the clearance ability was maintained in the completely obstructed kidney. PAH clearance values were 16.3, 13.6, 1.0, 0.9, 0.9 ml/hr/kg b.w. at 3, 5, 10, 20 and 40 days obstruction respectively. PAH clearance decreased sharply during early stage of obstruction and tended to reach a fixed low value at over 10 days of obstruction. Our experimental method seemed to be available to estimate the clearance ability of chronically, unilaterally and completely obstructed kidney.     

Absence of unilateral pulmonary circulation, detected by perfusion scintigraphy of the lung, and its clinical significance

Single acute shortage of pulmonary circulation may cause a life threatening condition, its definitive lack--in consequence of developmental trouble--decreased loading and inclination to infections. It's recognition is most easy by non invasive isotope perfusion pulmonary scintigraphy. Frequency, diagnostic difficulties are a little bit known in Hungary, therefore retrospective investigations were performed by the authors. Examining 961 perfusion pulmonary scintigraphic material of a four year (1990-1994) period-among them that of 52 children-in 8 cases total perfusion-lack of one lung-side was found. Surveyng history of 5 children and 3 adults, besides conventional physical and X-ray suspicion-sings, attention is drawn to signs of non-invasive perfusion and aerosol inhalation pulmonary scintigraphy which are more suitable to demonstrate deviations. In the background of severe circulatory trouble there have been found in one infant grave bronchial stenosis, in 4 children--with different age--arteria pulmonalis agenesia at right, and in 1 young adult (with Fallot-tetralogy), ateria pulmonalis agenesia at left. One of the other adults had bronchial carcinoma, and the other massive pulmonary embolisation. In their diagnostic schedule besides isotope investigations, importance of cardiologic echo-examinations, and the bronchoscopy has been stressed respectively. Catheterisation of the heart is important only in selected cases.     

Sonography, CT, CT sialography, MRI and MRI sialography in investigation of the facial nerve and the differentiation between deep and superficial parotid lesions

Three types of veneer restorations (VRs) were evaluated for recognition by two groups of observers to study the aesthetic result. The different types of VRs were: porcelain, direct resin composite and indirect resin composite. One month after insertion of the VRs, colour transparencies were made of smiling patients randomly selected from a group of 112 patients participating in a clinical trial. The slides were evaluated by five dentists who were not familiar with the patients and by 25 beautician students (BS). Dentists were asked to locate the VRs which were present in the patients and to specify the type of VR. BS were only asked to locate the VRs. To trace a possible relationship between the aesthetic result of the treatment and a number of variables, ANOVA was applied to evaluate the variables: 'discolouration of the teeth' before treatment, 'type of VR' and 'number of VRs'. Agreements in judgement were expressed in Cohen-Kappa coefficients. The results showed that the dentists could locate the VRs quite well (Kappa coefficient 0.64 +/- 0.28) but for BS this was lower (Kappa coefficient 0.43 +/- 0.27). The more VRs were made in one patient, the more difficult it was to locate them correctly. The other variables had no significant effect on the recognition of the VRs. It was not possible for the dentist observers to differentiate between the types of VRs.     

Fluorine-18-FDG PET and technetium-99m antigranulocyte antibody scintigraphy in chronic osteomyelitis

The aim of this study was to assess the usefulness of PET with 2-18F-fluoro-2-deoxy-D-glucose (FDG), as compared to immunoscintigraphy (IS) with 99mTc-labeled monoclonal antigranulocyte antibodies (AGAbs), in the detection of chronic osteomyelitis. METHODS: Fifty-one patients suspected of having chronic osteomyelitis in the peripheral (n = 36) or central (n = 15) skeleton were evaluated prospectively with static FDG PET imaging and combined 99mTc-AGAb/99mTc-methylene diphosphonate (MDP) bone scanning within 5 days. FDG PET and IS were evaluated in a blinded and independent manner by visual interpretation, which was graded on a five-point scale of two observers' confident diagnosis of osteomyelitis. Receiver operating characteristic (ROC) curve analysis was performed for both imaging modalities. The final diagnosis was established by means of bacteriologic culture of surgical specimens and histopathologic analysis (n = 31) or by biopsy and clinical follow-up over 2 yr (n = 20). RESULTS: Of 51 patients, 28 had osteomyelitis and 23 did not. According to the unanimous evaluation of both readers, FDG PET correctly identified 27 of the 28 positives and 22 of the 23 negatives (IS identified 15 of 28 positives and 17 of 23 negatives, respectively). The area under the ROC curve was 0.97/0.97 (reader 1/reader 2) for FDG PET and 0.87/0.90 for IS, with a high degree of interobserver concordance (K-values were 0.96 for FDG PET and 0.91 for IS). In the central skeleton, the ROC curve area was 0.98/1.00 for FDG PET and 0.71/0.77 for IS (p<0.05). On the basis of ROC analysis, the overall accuracies of FDG PET and IS in the detection of chronic osteomyelitis were 96%/96% and 82%/ 88%, respectively. With regard to the optimal threshold values, sensitivity and specificity were 100%/97% and 95%/95% with FDG PET, compared to 86%/92% and 77%/82% with IS, respectively. CONCLUSION: In the peripheral skeleton, both FDG PET and combined 99mTc-AGAb/99mTc-MDP scanning are appropriate imaging modalities to diagnose chronic osteomyelitis. FDG PET additionally allows reliable differentiation between osteomyelitis and infection of the surrounding soft tissue. In the central skeleton within active bone marrow, FDG PET is highly accurate and superior to AGAb imaging in the diagnosis of chronic osteomyelitis, which frequently presents as a nonspecific photopenic lesion at scintigraphy with labeled white blood cells.     

Monaural sound localization: acute versus chronic unilateral impairment

We report that choline acetyltransferase (ChAT) activity and neuronal survival were enhanced in rat septal neurons cocultured with hippocampal neurons. The enhancement of ChAT activity also occurred as a result of the addition of hippocampal conditioned medium (HpCM). When septal neurons from embryonic day 17 (E17) rats were cocultured with hippocampal neurons, ChAT activity was increased 2-fold compared with homogeneous culture of septal neurons. By contrast, no increase in ChAT activity was observed in coculture of septal and neocortical neurons. Treatment with HpCM obtained from cultured E19 rat hippocampal neurons enhanced the ChAT activity of E17 rat septal neurons. The enhancement of ChAT activity caused by coculture with hippocampal neurons and that caused by the addition of HpCM were not blocked by the addition of anti-nerve growth factor (NGF) antibody, suggesting that NGF, which is known to increase the ChAT activity of septal neurons both in vivo and in vitro, did not participate in the increase of ChAT activity. These findings indicate that possible target-derived neurotrophic factor(s), other than NGF, from hippocampal neurons enhance(s) the ChAT activity of septal neurons.     

Treatment of chronic unilateral frontal sinusitis by removal of the interfrontal septum

External surgical treatment of unilateral chronic frontal sinusitis by removal of the interfrontal septum is described. Eleven patients were treated by this method with excellent cosmetic results and only one transient recurrence.     

Role of Bed Discordance at Asymmetrical River Confluences

This paper studies laboratory open-channel confluences using a 3D, elliptic solution of the Reynolds-averaged Navier-Stokes equations, including a method for approximating the effects of water surface elevation patterns and a renormalization group modified form of the k-ε turbulence model. The model was tested by comparison with laboratory measurements of an asymmetric tributary junction. This suggests that although the model is unable to reproduce the quantitative detail (notably upwelling velocity magnitudes) of the flow structures as measured in laboratory experiments, statistically significant aspects of the experimental observations are reproduced. The model is used to (1) describe and explain the characteristic flow structures that form in a confluence with one of the tributaries angled at 45°, both with and without an elevation difference (bed discordance) in the angled tributary; and (2) investigate the relative importance of junction angles (30°, 45°, and 60°), bed discordance, and ratio of mean velocities in the tributary channels upon flow structures. This shows that bed discordance significantly enhances secondary circulation because of the effects of flow separation in the lee of the bed step, which significantly increases lateral pressure gradients at the bed and reduces water surface superelevation in the center of the tributary and water surface depression at the downstream junction corner. Extension to consideration of a number of junction angles, levels of bed discordance, and velocity ratios suggests that a small (10%) reduction in tributary depth can significantly increase the intensity of secondary circulation, albeit in a relatively localized manner. Simulations involving a numerical tracer illustrate the importance of bed discordance for mixing between the two flows and question the use of simple 2D parameterizations of mixing processes that do not consider bed discordance when the latter is present.     

Aseptic sialadenitis in preterm infants associated with long-term oro-gastric tube feeding

Sialadenitis is a rare disease in the newborn and the pathogenesis in this age group is not fully understood. We report five cases of neonatal sialadenitis in stable preterm, gavage-fed infants at 2 to 6 weeks postnatal age. The occurrence of sialadenitis was observed in temporal relation to changes in enteral feeding routines in the unit which were initiated with the objective of promoting full breast feeding at discharge. Clinical presentation consisted of a tender palpable mass over one of the salivary glands, low-grade (37.5-38.3 degrees C) fever in conjunction with clinical malaise. C-reactive protein and white blood cell count were only moderately elevated. No suppuration from salivary ducts was present. Bacterial cultures were invariably negative. Viral investigations were not carried out. Aseptic sialadenitis was suggested as the cause of the symptoms. The clinical course was benign and the local tender mass over the salivary gland vanished shortly after intravenous fluids and antibiotics were started. CONCLUSION: Long-term exclusive oro-gastric feeding may result in reduced reflex salivary gland stimulation, saliva production and hence ductal clearance of mucoid saliva, leading to functional ductal obstruction and local inflammation.     

Diagnostic value of myocardial thallium stress scintigraphy in the detection of coronary artery disease in patients undergoing chronic hemodialysis

Atherosclerotic heart disease is the leading cause of death in patients with end stage renal disease, but its non invasive detection remains difficult because of a low efficacy of exercise testing. The aim of the study was to evaluate diagnostic accuracy of thallium myocardial imaging after dipyridamole combined with exercise. Forty two chronic dialysis patients (34 men, 8 women) aged 55 +/- 11 years (range: 36 to 75) without symptom of angina nor myocardial infarction were studied. In each patient, an echocardiography, a myocardial scintigraphy with dipyridamole combined with symptom-limited exercise, and coronarography were performed. A coronary heart disease was diagnosed by coronarography in 10 patients (4.5 and 1 respectively with 1, 2 and 3 vessels diseased). Echocardiography detected a left ventricular hypertrophy (LVH) in 26 patients and a regional asynergia in 14 patients. A positive scintigraphy was present in 11 patients. Three false-positive and 2 false-negative on scintigraphy were noted. Sensibility, specificity, positive predictive value and negative predictive value were respectively evaluated at 80, 73, 73 and 93%. All the five patients with either false-positive or false-negative scintigraphy exhibited a LVH. CONCLUSION. In chronic dialysis patients, coronary heart disease may be detected by thallium myocardial imaging after dipyridamole combined with exercise.     

111In-pentetreotide scintigraphy is superior to 123I-MIBG scintigraphy in the diagnosis and location of chemodectoma

Chemodectomas, or glomus tumours, are unusual head and neck paragangliomas. A non-invasive imaging technique, 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy, has long been used for the diagnosis of all types of paraganglioma. The aim of this study was to evaluate and compare classic 123I-MIBG scintigraphy with the more recent 111In-pentetreotide scintigraphy in the diagnosis and location of chemodectomas. We performed 123I-MIBG and 111In-pentetreotide scintigraphy in eight patients (7 females, 1 male) with histologically or radiologically confirmed chemodectomas (five carotid body and three jugulotympanic chemodectomas). 123I-MIBG uptake was visualized in four patients on planar views and SPET images (sensitivity 50%); uptake was low in three patients. Using 111In-pentetreotide scintigraphy, all chemodectomas in eight patients were visualized (sensitivity 100%) and 111In-pentetreotide uptake was high in all cases. In conclusion, our results indicate that 111In-pentetreotide scintigraphy is superior to 123I-MIBG scintigraphy in the diagnosis and location of chemodectomas. In-pentetreotide or 123I-MIBG uptake suggests a neuroendocrine origin, providing important functional information in the diagnosis of chemodectomas. Moreover, 111In-pentetreotide scintigraphy permits a good classification of patients with or without somatostatin receptors in the chemodectoma in the application of pharmacological therapy with somatostatin analogues to inoperable tumours. The main therapeutic action of cold somatostatin analogues is to inhibit hormonal hypersecretion in different neuroendocrine tumours. In chemodectomas, however, the most important effect of somatostatin analogues is to reduce tumour volume or inhibit growth progression.     

Discordance of technetium-99m-HMPAO and technetium-99m-ECD SPECT in herpes simplex encephalitis

Technetium-99m-hexamethyl propyleneamine oxime (HMPAO) and 99mTc-ethyl cysteinate dimer (ECD) accumulate in brain tissue in proportion to regional cerebral blood flow in healthy subjects and in patients with a variety of neurological diseases. We report on four patients with herpes simplex encephalitis and the discordance between these two approved cerebral perfusion imaging radiopharmaceuticals. CONCLUSION: SPECT images showed unilateral regional increase of 99mTc-HMPAO uptake and decrease of 99mTc-ECD uptake in the affected temporal lobe.