Ruptured aneurysm with intracerebral hemorrhage in an 8 year old boy

Report on a case of aneurysm in a child and its treatment with discussion of its rarity and origin.     

Decreased virulence of a pneumolysin-deficient strain of Streptococcus pneumoniae in murine meningitis

Pneumolysin, neuraminidases A and B, and hyaluronidase are virulence factors of Streptococcus pneumoniae that appear to be involved in the pathogenesis of meningitis. In a murine model of meningitis after intracerebral infection using mutants of S. pneumoniae D39, only mice infected with a pneumolysin-deficient strain were healthier at 32 and 36 h, had lower bacterial titers in blood at 36 h, and survived longer than the D39 parent strain. Cerebellar and spleen bacterial titers, meningeal inflammation, and neuronal damage scores remained uninfluenced by the lack of any of the virulence factors.     

Heterogeneity in the Dorsal Subiculum of the Rat. Distinct Neuronal Zones Project to Different Cortical and Subcortical Targets

The aim of the present study was to relate the distribution of efferents of the dorsal subiculum to their origin along the proximodistal axis of the subiculum. The distribution of subicular projections was studied in detail by means of the sensitive anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHA-L), and the precise origin of these projections analysed with retrogradely transported fluorescent tracers, using double- and triple-labelling protocols. Injections of PHA-L in the proximal part of the dorsal subiculum, i.e. that part which borders field CA1, result in labelling of the infralimbic, entorhinal and perirhinal cortices, the nucleus accumbens and the lateral septal region, the interanteromedial nucleus of the thalamus, the core of the nucleus gelatinosus, and the mammillary nuclei, in particular in the rostral parts of the medial nucleus. In contrast, injections in the distal part of the dorsal subiculum, i.e. that part which borders the presubiculum, give rise to labelling in the retrosplenial and postrhinal cortices, the presubiculum, the anterior thalamic complex, the shell of the nucleus gelatinosus, and the mammillary nuclei, preferentially in the caudal part of the medial nucleus. The results of injections of different retrograde tracers, simultaneously placed in two or three targets of the subicular efferents, confirm the results of the anterograde tracing experiments. Moreover, they clearly demonstrate that the population of subicular neurons which, for example, projects to the nucleus accumbens and the interanteromedial nucleus of the thalamus is almost completely segregated from the population that projects to the retrosplenial cortex and the anterior complex of the thalamus. Thus within the dorsal subiculum, populations of neurons can be differentiated so that each population projects to a unique set of target structures. These cell populations are differentially positioned along the proximo-distal axis. In view of additional evidence indicating that some of the major afferents to the subiculum are organized along the same axis, we suggest that the heterogeneity of the dorsal subiculum along the proximo-distal axis reflects a general organizational characteristic of this hippocampal field.     

Signal transduction pathway of the muscarinic receptors mediating gallbladder contraction

In gallbladder smooth muscle, carbachol interacts with M₃ receptors to mediate contraction. To examine components of the intracellular second messenger system that is coupled to these receptors we have tested whether carbachol stimulates the formation of inositol phosphates (IP) to cause contraction. Guinea pig gallbladder muscle strips were prelabeled with [³H]inositol and were incubated with 0.1 mmol/l carbachol, a concentration causing maximal contraction. [³H]inositol monophosphates, [³H]inositol bisphosphates and [³H]inositol trisphosphates and contraction were measured at various times (0–90 s). To examine whether a pertussis toxin-sensitive guanine nucleotide binding protein is coupled to the muscarinic receptors, guinea pigs were pretreated with pertussis toxin (180 g/kg i.v./24 h). The effectiveness of pertussis toxin treatment was determined by measuring [³²P]ADP-ribosylation of a –40/41 kDa protein from gallbladder homogenates. Carbachol caused a significant time-dependent increase in the formation of [³H]inositol monophosphates, [³H]inositol bisphosphates and [³H]inositol trisphosphates. The time course of [³H]inositol trisphosphate turnover caused by carbachol was biphasic, and was detectable at 15 s and maximal at 60 s; at 75 s and 90 s formation of [³H]inositol trisphosphates decreased, whereas the time course of carbachol-induced contraction of the gallbladder smooth muscle strips reached a plateau after 90 s. The effects of carbachol on [³H]inositol trisphosphates and on contraction were abolished by atropine. Pretreatment with pertussis toxin resulted in ADP-ribosylation of a 40/41 kDa protein from gallbladder cell membranes but did not affect the concentration-response or time course of carbachol-induced contraction. These results indicate that carbachol-induced contraction of gallbladder smooth muscle cells is accompanied by the activation of inositol phosphate turnover and does not involve a pertussis toxin-sensitive G-protein.This article is based in part on the doctoral thesis of Burkhard Mackensen at the Faculty of Medicine, University of Hamburg, Germany. Some of the results were presented at the meeting of the American Gastroenterological Association (AGA) in San Francisco 1992 (von Schrenck et al. 1992) Correspondence to: T. von Schrenck at the above address     

Detection of migrated allogeneic oligodendrocytes throughout the central nervous system of the galactocerebrosidase-deficient twitcher mouse

Summary Galactocerebrosidase-deficient oligodendrocytes of twitcher (twi/twi) mice degenerate prematurely. Transplantation of normal bone marrow cells has been shown to alleviate symptoms and to prolong survival time. However, characteristic ataxia (twitching) is not cured. In an attempt to improve further the condition of twitcher mice, allogeneic foetal liver cells were transplanted as a source of normal haemopoietic stem cells and supplemented with intracerebral transplantation of foetal brain cells. A reliable method was developed to detect donor-type cells in brain tissue. Bacteriophage . transgenic foetal mice were used as donors of both foetal liver and brain cells. Integrated copies of . DNA in donor cells were detected byin situ hybridization with biotinylated probes, which were then stained using streptavidin alkaline phosphatase. This technique was combined with immunohistochemistry to distinguish donor-type oligodendrocytes from macrophages. Immunoperoxidase staining with an antiserum to carbonic anhydrase-II produced dark perikarya of oligodendrocytes. The results demonstrated that local foetal brain cell grafts resulted in a wide dissemination of donor-type oligodendrocytes throughout the twitcher brain. The addition of a foetal brain cell graft to haemopoietic cell transplantation resulted in significantly prolonged survival of twitcher mice.     

Early events leading to renal injury in obese Zucker (fatty) rats with type II diabetes

Early events leading to renal injury in obese Zucker (fatty) rats with type II diabetes. BACKGROUND: More than half of the new patients admitted to dialysis therapy in some centers are diagnosed with type IIb diabetes, that is, diabetes associated with obesity. This study searched for a common final pathway of renal damage in this progressive renal disease. METHODS: The evolution of biochemical and morphological renal changes was examined in 6- to 60-week-old Zucker rats (fa/fa-rats), a model of obesity associated with type II diabetes. RESULTS: fa/fa-rats exhibited pronounced hyperinsulinemia and hyperlipidemia at 6 weeks and became diabetic after 14 weeks of age. Significant focal segmental glomerulosclerosis was first noted in 18-week-old fa/fa-rats and tubulointerstitial damage and proteinuria in 40-week-old fa/fa-rats. A comparison of kidneys of six-week-old fa/fa-and lean control (Fa/?) rats by immunohistology revealed a 1.8-fold increase in glomerular monocyte/macrophage counts in fa/fa-rats and a significant increase in de novo desmin expression in podocytes. Electron microscopy demonstrated an increase in the number of podocyte mitochondria and intracytoplasmic protein and fat droplets. Podocyte desmin scores markedly increased until week 18 in fa/fa-rats, whereas glomerular monocyte/macrophage counts peaked at 3.2-fold at week 14. Podocyte desmin expression, but not glomerular macrophage infiltration, correlated with damage in adjacent tubular cells, as evidenced by their de novo expression of vimentin. Progressive glomerular hypertrophy was detected in fa/fa-rats after 10 weeks. GBM width was significantly increased in 14-week-old fa/fa-rats as compared with lean controls. Mesangial cell activation (de novo expression of alpha-smooth muscle actin) and proliferation was low to absent throughout the observation period in fa/fa-rats. Renal cell death counts (TUNEL) remained unchanged in 6- to 40-week-old fa/fa-rats. Tubulointerstitial myofibroblast formation and matrix accumulation occurred late during the study duration in fa/fa-rats. CONCLUSION: These data suggest that early progressive podocyte damage and macrophage infiltration is associated with hyperlipidemia and type IIb diabetes mellitus, and antedates both the development of glomerulosclerosis and tubulointerstitial damage.     

Non-invasive bladder volume measurement for the prevention of postoperative urinary retention: validation of two ultrasound devices in a clinical setting

Ultrasound scanning of bladder volume is used for prevention of postoperative urinary retention (POUR). Accurate assessment of bladder volume is needed to allow clinical decision-making regarding the need for postoperative catheterization. Two commonly used ultrasound devices, the BladderScan® BVI 9400 and the newly released Prime® (Verathon Medical®, Bothell, WA, USA), with or without the ‘pre-scan’ option, have not been validated in clinical practice. The aim of this study was to assess the performance of these devices in daily clinical practice. Between June and September 2016 a prospective observational study was conducted in 318 surgical patients (18 years or older) who needed a urinary catheter perioperatively for clinical reasons. For acceptable performance, we required that the volume as estimated by the BladderScan® differs by no more than 5% from the actual urine volume after catheterization. The Schuirmann’s two one-sided test was performed to assess equivalence between the BladderScan® estimate and catheterization. The BVI 9400® overestimated the actual bladder volume by +?17.5% (95% CI +?8.8 to +?26.3%). The Prime® without pre-scan underestimated by ? 4.1% (95% CI ? 8.8 to +?0.5%) and the Prime® with pre-scan underestimated by ? 6.3% (95% CI ? 11.6 to ? 1.1%). This study shows that while both ultrasound devices were able to approximate current bladder volume, both BVI 9400® and Prime®—with and without pre-scan—were not able to measure the actual bladder volume within our predefined limit of ±?5%. Using the pre-scan feature of the Prime® did not further improve accuracy.