Morphological changes in rat submandibular gland mucous cells during fixation with 10% formalin

The features of mucous cells in 10% formalin (FA)-fixed submandibular glands differ markedly from those fixed in glutaraldehyde (GA). We therefore studied morphological changes in mucous cells during 10% FA fixation. Mucous cells were fixed in either 10% FA, neutral sodium-phosphate-buffered (Na-PBed) 10% FA, ice-cold 10% FA or an ice-cold fixative mixture of 2.0% paraformaldehyde (PA) and 0.5% GA. Two different methods were used: immersion fixation and venous perfusion fixation. The 10% FA-fixed tissues had elliptical or flattened nuclei, a clear cytoplasm and no secretory granules. Tissues fixed with the fixative mixture displayed almost round nuclei, a broad endoplasmic reticulum and abundant secretory granules in the cytoplasm. Tissues immersion-fixed with neutral Na-PBed 10% FA or perfusion-fixed with ice-cold 10% FA had almost the same light microscopic appearance as that of the mixture-fixed tissues. To elucidate the process of morphological changes during 10% FA fixation at room temperature, samples immersed in 10% FA for varying periods of time were postfixed immediately in the fixative mixture and exposed to microwave irradiation. This method produced a variety of findings, even within the same section. There was a significant difference in the findings seen in the center of the section and at the periphery. The initial changes caused by 10% FA were rupture of the secretory granules located in the perinuclear region and destruction of the perinuclear organelles such as Golgi apparatus, mitochondria and endoplasmic reticulum. Absorption of the endoplasmic reticulum progressed so that the pennuclear region became translucent. To obtain a better structure in mucous cells from the fixed submandibular gland tissues, an appropriate fixative such as GA should be used and the fixative should infiltrate into the tissue as quickly as possible.     

Impedance plethysmography for blood flow measurements in human limbs

The cross-sectional area of a limb varies along the extremity. This is of great importance when impedance plethysmography is used for limb blood flow studies. The actual measurement site, as well as the interelectrode distance, must be carefully selected to avoid underestimation of the blood flow value. The distance between the potential electrodes should be less than 10 cm for an adult subject.     

Magnetic resonance imaging of the brain in Wilson's disease

Summary Fifteen patients with Wilson's disease were examined, using spin-echo (SE) and gradient-echo (GE) sequences with 0.5 T and 1.5 T magnetic resonance (MR) imagers. They fell into three groups: groups 1 and 2 were examined retrospectively after 3–18 years of treatment, while group 3 was examined prospectively from the start of treatment, after recommencement of treatment, or inadequate treatment. MRI was sensitive to changes in the basal ganglia at sites typical of Wilson's disease and was useful for documenting the effects of treatment. It was found necessary to estimate the relaxation times T1 and T2, to better assess improvement or transient worsening of the disease in the prospective group. Residual cavitation and gliosis could be distinguished in the retrospective group using a subtraction technique.     

Über den autoplastischen Aortenklappenersatz

Zusammenfassung Die beschriebene Methode erlaubt den teilweisen oder vollst?ndigen Ersatz verkalkter oder deformierter Aortenklappen bei der operativen Behandlung erworbener Aortenvitien. H?modynamische Untersuchungen zeigen, da? diese Klappenplastik für die Austreibung des Blutes aus der linken Kammer kein mechanisches Hindernis darstellt. Dagegen liegt in den meisten F?llen eine leichte, gelegentlich auch eine schwere Klappeninsuffizienz vor. Die Patienten mit schwerer Insuffizienz wiesen alle bicuspide Klappen auf, und wahrscheinlich ist die Insuffizienz auf mangelhafte Technik zurückzuführen. Für eine Verschlechterung der Klappenfunktion, insbesondere für eine Zunahme der Insuffizienz, liegen bis jetzt w?hrend einer Beobachtungszeit bis zu 3 Jahren keine Anhaltspunkte vor. Thromboembolische Komplikationen traten in unserem Beobach-tungsgut nicht auf. Ein Vorteil der Methode ist, da? das zum Klappenersatz erforderliche Gewebe jederzeit zur Verfügung steht und da? bei gewissen F?llen die Rekonstruktion oder der teilweise Ersatz einzelner Klappentaschen m?glich ist. Es ist allerdings noch verfrüht, über die Methode ein definitives Urteil abzugeben. Sie hat gegenüber der Einsetzung alloplastischer Prothesen den Nachteil, da? der Eingriff technisch schwieriger ist und mehr Zeit beansprucht.     

Craniofacial growth in shunt-treated hydrocephalics: a four-year roentgenocephalometric follow-up study

The craniofacial growth of 24 shunt-treated hydrocephalics aged 5–15 years was evaluated over a 4-year period, by comparing changes in linear and angular cephalometric variables with those of an age- and sexmatched control group. The main findings were increased calvarial thickness, increased cranial base flexure, superior displacement of the sella, and a tendency for the gonial angle to remain more obtuse in the shunt-treated patients. As craniofacial growth in the latter differed only slightly from that observed in the controls, the deviations in facial morphology observed in a previous cross-sectional study of shunt-treated hydrocephalics can be taken to represent a long-term effect of the shunt treatment.     

Pharmacokinetics of oral noscapine

The relative bioavailability in 20 healthy volunteers of 100 mg, 200 mg and 300 mg tablets of noscapine and 200 mg as a solution has been assessed in a four-way cross-over study, with repeated administration of the 200 mg dose to assess intraindividual variability. There was a disproportionate increase in the AUC of noscapine tablets, as a 3-fold increase in dose produced a 9-fold rise in AUC. This dose-dependency could mainly be attributed to saturable first-pass metabolism of the drug. Administration of noscapine as a solution resulted in a significantly higher maximal concentration at an earlier time-point and a higher AUC than the corresponding dose as tablets. Repeated administration of noscapine tablets and solution yielded higher AUC on the second dosing occasion. No cause for this carry-over effect was found, and the contribution of remaining noscapine was negligible. The terminal half-life of noscapine, which was independent of formulation or dose size was 4.5 h. Both inter- and intraindividual variability in noscapine kinetics were very high, e.g. 73% and 51% CV of the AUC for the 200 mg tablet.     

Salt aggregation test for measuring cell surface hydrophobicity of urinaryEscherichia coli

The recently developed salt aggregation test for measuring relative surface hydrophobicity of bacteria was used to studyEscherichia coli strains isolated from urinary tract infections. Of the 232 strains tested 166 (71.5 %) aggregated in salt solutions of varying molarity (0.1–1.6 M final concentration). Mannose-resistant haemagglutination of various erythrocyte species and/or mannose-sensitive haemagglutination of guinea-pig erythrocytes was seen in 144 of the 166 salt aggregating strains. Two salt aggregation-negative (hydrophilic) strains exhibited mannose-sensitive haemagglutination. Fimbriae of varying morphology were seen in salt aggregating strains. Strains with type 1 fimbriae only generally showed lower surface hydrophobicity than strains exhibiting mannose-resistant haemagglutination. Growing strains at 18 °C suppressed fimbriation with a concomitant decrease in surface hydrophobicity and haemagglutination. The salt aggregation test proved to be a rapid and reproducible screening test for detecting bacteria with high surface hydrophobicity due to surface protein of fimbrial (haemagglutinating or non-haemagglunating) and non-fimbrial nature.     

Duodenal ulcer in army trainees during basic military training.

As part of a larger study of mental and psychosomatic reactions of decompensations or inadequacy during basic training, 2 the number and characteristics of persons afflicted with duodenal ulcer or other performance-impairing gastro-intestinal disorders during basic military training were studied.3Data were collected by extensive studies of all non-commissioned officers and private basic trainees in five Swedish training regiments, mainly through questionnares and by individual studies of certain selected groups emplying interviews and personality tests. The trainees' own reports were complemented with information from the regimental physician, medical records, military registers, fellow trainees and platoon commanders. Since the information on individual participants was collected on different occasions, before and during basic training, the investigation is both prospective and retrospective.A cardianal problem in researching duodenal ulcer is that the experimental groups are almost always comprised of patient materials. Since the characteristics of htose individuals with duodenal ulcer that have not consulted a physician for their symptoms are not known, it is difficult to make generalizations about individuals with a duodenal ulcer on the basis of patient materials as the point of reference.We have found that there are differences between persons with gastro-intestinal disorders that have consulted a physician and those that have not, that local factors may influence the sick-role and illness behaviour, and that selection based on a predisposition to undrgo reactions of decompensation may be important for the connection between the illnes one wants to study and reports on social and interpersonal problems and psychological symptoms.In sum, a practically unselected group of trainees with a symptomatic duodenal ulcer during basic military training was studied. As regards personality and triggering problems, thisgroup appeared to be very heterogeneous. Probably the most remarkable findings were the similariries between the ulcer group and the non-X-rayed group, or all trainees with respect to reported problems before and during basic training, score on a neurois scale, and results in a test designed to measure defence mechanisms according to psychoanalytic theory.     

Effects of different rates of absorption of two benzodiazepins on subjective and objective parameters

Summary Two benzodiazepins with different rates of absorption have been compared in a double-blind cross over study in six healthy subjects using single doses of diazepam (Valium) 2, 5 and 10 mg and oxazepam (Sobril) 15, 25 and 50 mg. Further, oxazepam formulations with different rates of absorption have been compared in 8 healthy subjects. Lastly, the diurnal variation in serum levels during long-term therapy with the benzodiazepins has been followed up in a pilot study in hospital. Drug influence was assessed at intervals and showed that the quantitative and qualitative subjective effects as well as the alteration of reaction time and hand steadiness were more pronounced during the rising phase than in the constant plateau or falling phase of serum drug concentrations. Rapidity of increase in concentration appeared more important than the absolute level. Diazepam has the faster rate of absorption and had a significantly (p<0.05–0.001) greater influence at 30 min, and usually at 90 min, too, than oxazepam or the placebo. Oxazepam, even when administered as a formulation with near-maximal absorption rate, still had not high enough a rate of absorption to produce the distinctly identifiable onset of reactions characteristic of diazepam and did not give noticeable prolongation of reaction time or increased hand unsteadiness even at its maximal serum concentrations. The separate pilot study showed that relatively large diurnal variations in serum concentrations might occur during continuous treatment for more than four weeks and that a preparation with a high rate of absorption (diazepam) could still produce a subjectively apparent experience after each individual dose. It seems reasonable to assume that the risk of abuse, and equally also one of the factors increasing the risk of habituation to psycho-pharmaceutical drugs, is related to subjectively experienced effects, which, as shown above, depend to a large extent on the rate of absorption. For maintenance treatment a steady serum level adapted to the individual is probably to be preferred, while in acute treatment, for example, of attacks of anxiety, a compound with rapid absorption is required, and the therapeutic advantages must then be weighed against the greater risk of abuse.