The hippocampus in experimental chronic epilepsy: a morphometric analysis

The effect of intermittent seizures on the pyramidal neurons of the hippocampus is largely unknown. To determine whether recurrent seizures centered in the hippocampus can produce neuronal loss in this region, a morphometric analysis was performed from standardized sections of hippocampus using 5 groups of animals: (1) surgical control subjects, (2) rats kindled by the rapidly recurring hippocampal seizure (RRHS) paradigm, (3) kindled rats with a few additional limbic seizures (528 +/- 66 seizures), (4) kindled rats with many limbic seizures (1,523 +/- 130 seizures), and (5) rats experiencing limbic status epilepticus (SE) induced by "continuous" hippocampal stimulation. The RRHS and SE protocols induced significant neuronal loss in the CA1 region, but no evidence was found for additional cell loss with increasing numbers of intermittent seizures. These intermittent seizures were, however, associated with a significant thickening of the basal and apical dendritic fields of the CA1 region. These findings indicate that intermittent seizures produce no significant hippocampal neuronal loss and may result in a hypertrophy of CA1 dendritic fields.     

Proceedings of the Symposium ‘Angiotensin AT1 Receptors: From Molecular Physiology to Therapeutics’: STRUCTURAL CHANGES IN THE RENAL VASCULATURE IN THE SPONTANEOUSLY HYPERTENSIVE RAT: NO EFFECT OF ANGIOTENSIN II BLOCKADE

• 1 There is strong evidence for a renal basis to the development of hypertension in the spontaneously hypertensive rat (SHR). Alterations of the SHR renal vasculature, including the glomerulus, may be involved in the initiation and maintenance of hypertension in this animal model.
• 2 The arterial walls of pre-glomerular vessels of the SHR are hypertrophied compared with WKY vessels. Unlike other vascular beds in the SHR, this hypertrophy is independent of angiotensin II (AngII).
• 3 Glomerular number and volume are similar between SHR and the normotensive Wistar-Kyoto (WKY) rats. These results provide no support for the theory that a reduced filtration surface area within the kidneys of the SHR contributes to the elevated blood pressure in these animals.
• 4 Intrarenal hypertrophy may have similar haemodynamic consequences to clipping of the main renal artery, as in Goldblatt hypertension. Further analysis of the role of pre-glomerular arterial hypertrophy is warranted to determine its involvement in the initiation and maintenance of hypertension in the SHR.

     

53 a. Notwendigkeit und Anwendungsgebiet retrospektiver Analysen in einer Zeit der prospektiven kontrollierten Studien

Zusammenfassung Prospektiv-kontrollierte Studien sind die verläßlichsten Hilfsmittel, mit denen klinische Fragestellungen entschieden werden können. Für ihre korrekte Handhabung gibt es eine Fülle strenger Voraussetzungen, die sich in der Praxis meist nicht verwirklichen lassen. In diesen Fällen auf Forschung ganz zu verzichten, hieße sich in fataler Weise von einer Methode abhängig machen. Das Anwendungsgebiet retrospektiver Analysen umfaßt daher vor allem diesen Bereich im Sinne einer zweitbesten Lösung. Darüber hinaus ist der retrospektiven Betrachtungsweise eine innere Notwendigkeit für die medizinische Forschung eigen, wenn man auf kritische Reflexion des eigenen Tuns und auf das Angehen neuer Probleme Wert legt.     

Experimental parasitization of eggs of Triatoma maculata (Erichson) by the oriental microhymenopteran,Gryon triatomae Masner and comment on the susceptibility of other neotropical triatomines

The oriental microhymenopteran wasp, Gryon triatomaeMasner, 1975 was reared in eggs of triatomine bugs, including vectors of Chagas' disease. In particular, G. triatomae was maintained for 31 generations in eggs of Triatoma maculata (Erichson). Only one parasite develops in each bug egg and 30 to 40 days are required for completion of development at 24 ± 1 °C. Mean parasitization rate of 7484 eggs of T. maculata, in 54 rearings, was 34·7% with a range from zero to the highest rate of 86·7%. Mated females produce predominantly female progeny (mean sex ratio, 1 male : 6·7 females). Unmated females produce parthenogenetic males. The wasp reproduces in fertile eggs, from those recently laid to those with well-advanced bug embryos. Infertile eggs are not usually parasitized. Both sexes survive for one to two weeks unfed, but for several weeks (up to 16 for females) if fed (on honey). Frequent ovipositions may reduce survival. Successful parasitization by females persisted for about three weeks but declined subsequently.Abortions of developing Gryon were usually 10% or less. Brief comparison with other neotropical triatomine species indicates that eggs of Triatoma spp. are susceptible to G. triatomae; Panstrongylus spp. seem relatively poor hosts, and there is little or no parasitization of Rhodnius spp.     

Aluminum, zinc and copper concentrations in plasma in chronic renal insufficiency.

Plasma aluminium, zinc and copper were determined in 68 patients with chronic renal insufficiency and in 20 healthy individuals. In the renal insufficiency group 16 patients had received aluminium containing substances particularly phosphate binding drugs (aluminium hydroxide) for a long time. We observed that only the patients taking aluminium hydroxide showed elevated aluminium levels in plasma (controls: 0.86 +/- 0.27 mumoles/l; renal insufficiency: 3.05 +/- 1.63 mumoles/l). In two of these patients with symptoms of "dialysis dementia", plasma aluminium concentrations were markedly increased. The zinc concentrations in plasma of patients with renal insufficiency were slightly decreased (controls: 14.48 +/- 2.65 mumoles/l; renal insufficiency: 11.77 +/- 2.35 mumoles/l); the plasma copper concentrations were slightly increased (controls: 17.3 +/- 2.83 mumoles/l; renal insufficiency: 22.98 +/- 4.7 mumoles/l). There was a distinct decrease of plasma zinc concentrations in patients with raised aluminium levels. The clinical aspects of these changes are discussed.     

The evaluation of continuing medical education: a literature review.

The literature of continuing medical education (CME) program evaluation was reviewed and analyzed. The "State-of-the-art" of CME evaluation is depicted in a series of tables which indicate evaluation methods and results. Evaluation designs providing strong assurances of valid results were not often found. The weakness of most published evaluations limit possible conclusions about the effectiveness of CME.     

The use of BRIAC for evaluating therapeutic effectiveness

Forty-six children in eight different psychotherapeutic settings were evaluated at the beginning and at the end of a 12-month period by means of the Behavior Rating Instrument for Autistic Children (BRIAC). The younger children (3 to 6 years of age) were initially more severely disturbed and improved significantly more than the older children (7 to 9 years of age). The large, bleak, custodial residential center produced significantly less improvement in the children than did the other settings. However, among good programs—i.e., those which were sensitive to the behaviors and needs of the children and which were skillfully implemented by a dedicated and attentive staff—there was little evidence of differences in therapeutic effectiveness regardless of whether the therapy was behavior modification, education, psychoanalytically oriented relationship therapy, or activity therapy.     

The influence of bile salts and mixed micelles on the pharmacokinetics of quinine in rabbits.

The bioavailability of orally administered drugs can be influenced by interactions with food components and by physico-chemical conditions in the upper gastrointestinal tract. Normally, bile salts enhance the transport of lipophilic drugs across mucosal membranes. Bile salts are able to form stable mixed micelles consisting of fatty acids and phospholipids. Conventional micellar systems are known to solubilize lipophilic drugs having a low bioavailability. The influence of bile salts and mixed micelles on the pharmacokinetics of the lipophilic drug quinine was investigated in rabbits. Female rabbits were given intraduadenally quinine (5 mg/kg body weight) without and with incorporation into the micellar or mixed micellar systems. Blood was collected every 30 min for 6 h. In plasma, concentration of quinine was measured using HPLC. The plasma concentration-time profiles of quinine were significantly lower within the first 2 h after administration in presence of both the sodium salt of glycodeoxycholic acid (above the critical micellar concentration) as well as of mixed micellar systems consisting of glycodeoxycholic acid and palmitic acid and/or lecithin. The pharmacokinetic parameters AUC (relative bioavailability) and c(max) of quinine were significantly decreased by micellar systems in rabbits. These mixed micellar systems lower and not as expected, increase the absorption of quinine in vivo. Therefore, quinine should be orally administered at least 1h before food intake, particularly before fat intake.     

Empfehlungen und Standards für die Analgosedierung kinderkardiologischer Patienten

Monatsschrift Kinderheilkunde - Bei kinderkardiologischen Patienten bzw. Kindern mit angeborenen Herzfehlern werden häufig diagnostische oder therapeutische Prozeduren durchgeführt, die...