Influence of continuous levels of fentanyl in rats on the mu-opioid receptor in the central nervous system

The highly potent and efficacious mu-opioid agonist fentanyl was SC infused into rats with submaximal analgesic doses (0-1.14 mumol/kg/day) continuously for 8 days, checked by the constant daily urinary recovery of intact drug (0.43 +/- 0.031% of the daily dose). Tail-flick latencies measured at 24 (day 1) and 48 h (day 2) after starting the infusion were increased in a dose-dependent fashion compared with those before the infusion (day 0). However, at day 8, the latencies were increased only weakly, not significantly, revealing tolerance to the antinociceptive activity of fentanyl. Fentanyl at all doses showed no significant effect on the capacity (Bmax) and affinity (Kd) of the mu-opioid receptor binding of DAMGO to whole brain (Bmax 126.2 +/- 3.00 fmol/mg protein, Kd 1.00 +/- 0.04 nM) and spinal cord (Bmax 48.24 +/- 2.71 fmol/mg protein, Kd 1.93 +/- 0.13 nM) membranes gained from the rats after killing them at day 8. Gpp(NH)p increased the Kd for brain and spinal cord sites by 3.09 and 2.65, respectively, independent of the fentanyl dose. The infusion with fentanyl did not after the basal and forskolin-stimulated adenylate cyclase activity in the whole brain membranes, nor did it change the inhibition of the forskolin-stimulated activity by DAMGO. It is concluded that, in rats, constant long-term body levels of highly potent mu-agonists result in a tolerant state that, however, does not produce overall changes in the parameters of their specific receptor sites in the CNS, i.e., receptor capacity and affinity, and in the events closely related to them, i.e., their regulation by GTP and of adenylate cyclase. This does not exclude such possible changes to be restricted to specific regions in the CNS.

Primary shunt perfusion detected by colour flow Doppler imaging and its impact on liver allograft survival

Primary dysfunction (PDF) and eventual primary nonfunction (PNF) of liver allografts have been characterized by various clinical and laboratory parameters reflecting graft function, cellular integrity and extrahepatic influence following orthotopic liver transplantation (OLT). During the past 6 yr we have been able to demonstrate that this potentially devastating condition is routinely accompanied by a pathological initial perfusion pattern detected by colour flow doppler imaging (CFDI) within hours following OLT. In the majority of PDF cases (n = 30) CFDI revealed increased vascular resistance in regard to arterial blood flow to the malfunctioning graft, with a resulting 1-yr graft survival rate of 80% following the institution of early prostaglandin therapy in this group of patients. A completely different perfusion pattern was noticed by CFDI in a total of 13 cases with grossly decreased arterial resistance, resulting in an apparently supranormal arterial blood supply together with a reduced portal inflow in comparison to primarily functioning grafts. The presence of this pathologic graft perfusion was explained by the formation of arterio-portal shunts within the graft during conservation and reperfusion, leading to a 1-yr graft survival of merely 46.1%.

[surgical relevance of diagnostic imaging in abdominal tumors--decision making in retroperitoneal tumors]

The indication for surgical treatment of tumors of the retroperitoneum should not depend on findings of radiological examinations, because all radiographic procedures lack tissue specificity. Instead, it can only be determined histologically after an open biopsy or resection of the tumor, which should always be attempted. With the help of appropriate radiological examinations, a retroperitoneal mass will not only be detected, but the relationship to the adjacent anatomical structures will also be delineated. Therefore, valid information for planning the operation and estimating the morbidity and mortality can be provided for the surgeon.

[Interventional radiologic procedures in postoperative complications after liver transplantation]

PURPOSE

Postoperative complications contribute significantly to the morbidity and mortality of liver transplant patients. The management of these complications requires a multidisciplinary approach in which interventional radiology plays an integral role. Indications, techniques, and results of radiological interventions in the management of the liver transplant patient are presented.

MATERIAL AND METHODS

During a 10-year period, 52 out of 420 liver transplant recipients underwent radiological interventions, including angioplasty (n = 20), embolization (n = 2), percutaneous drainage (n = 11), and biliary interventions (n = 19).

RESULTS

Nine out of ten arterial stenoses located at the anastomoses (n = 8), within the liver (n = 1) and in the coeliac trunk (n = 1) were successfully treated by balloon dilatation. Angioplasty of supra- or infrahepatic anastomotic stenoses of the i.c.v. (n = 5) provided long-term success only in combination with stent implantation. Portal vein stenoses and chronic thrombosis were treated by balloon dilatation and stent insertion via transhepatic catheterization of the portal vein. Late strictures of bile-duct anastomoses can be managed by ante- or retrograde interventions. If biliary complications are related to inflammatory or septic problems, the prognosis of graft survival is poor.

CONCLUSION

Interventional radiological procedures are very useful in the management of vascular and biliary complications after liver transplantation. These techniques provide a cure in many situations, and thus, surgical interventions may be avoided in selected cases.

[Radiologic interventions in anastomosis complications after lung transplantation]

PURPOSE

Bronchial and arterial anastomotic stenoses are major complications after lung transplantation. Interventional techniques provide a definitive cure in certain cases.

MATERIAL AND METHODS

Three out of four patients had ischemia-related stenoses of the bronchial anastomoses postoperatively; one patient developed malacia of the bronchus main stem 1 year after transplantation. Four patients has stenoses of the arterial anastomoses, which resulted in hemodynamic instability and reduced perfusion of the graft.

RESULTS

Stent implantation in the bronchial anastomoses (n = 3) and in the main stem (n = 1) improved ventilation and oxygen saturation in all patients. The stents were incorporated by mucosal overgrowth, as demonstrated by endoscopy, as early as 6 weeks after implantation. Balloon dilatation (n = 3) and stent implantation (n = 1) were successfully performed in 4 patients with stenoses of the arterial anastomoses. The mean transstenotic pressure gradient of 9.5 mm Hg was reduced to 2.2 mm Hg after angioplasty. Lung perfusion shifted towards the grafts, as shown by 99mTc perfusion scans.

CONCLUSION

The minimally invasive techniques of interventional radiology are very effective in the treatment of anastomotic complications after lung transplantation and may avoid surgery in certain cases.

[Geriatric rehabilitation needs in Cologne: the concept of "integrated geriatric rehabilitation"]

Given a growing number of elderly people and the related consequences for the health care system, such as increasing numbers of persons with chronic diseases or in need of long-term nursing care, the present rehabilitation system must be extended and new services be introduced. Hospitals in Cologne report that an average 48% of their geriatric patients are in need of rehabilitation measures. Taking into account the patients' willingness and capacity to undergo rehabilitation treatment, the figure reduces to 30%. Based on the number of geriatric patients treated in hospital each year, rehabilitation facilities for 15416 geriatric patients a year have to be provided. About two thirds of the patients require continued hospital treatment after the acute phase. Obviously, these treatments are not only performed in the geriatric departments of the hospitals, as only 161 geriatric beds are available in Cologne. One third of the patients could be taken care of on a partial hospitalization or outpatient basis after the acute phase. Thus, limiting a patient's length of stay in hospital could have a cost-containment effect. As partial hospitalization and outpatient rehabilitation facilities are lacking, the Cologne "Geriatrics" study group has developed a concept of "integrated geriatric rehabilitation", suggesting the establishment of mobile rehabilitation teams. The concept aims at developing a cooperative network linking outpatient with partial hospitalization and inpatient services, and including the physicians at community level.

[Dementia and the Dutch Reading Tests for Adults]

The Dutch Adult Reading Test (DART) is a method to assess premorbid intelligence in brain damaged patients. This article describes a study in which subjects without dementia (n = 25), with mild dementia (n = 11) and moderate to severe dementia (n = 11) were tested with the DART. DART-scores of the no dementia and mild dementia groups did not differ, but were significantly lower in moderate to severe dementia. So, the DART appears to be sensitive to more severe cerebral pathology as occurs in more advanced dementia, but is very useful with patients with mild cognitive deterioration. For the first time the test-retest-reliability of the DART was determined: r = 0.87 to 0.98. Except in the severe dementia group the DART strongly correlates with educational level.

Time-dependent changes of insufficiency fractures of the sacrum: intraosseous vacuum phenomenon as an early sign

Sacral insufficiency fractures develop over a period of time and show time-dependent changes. We report on 15 CT examinations of 5 patients with early-stage insufficiency fractures of the sacrum. In 4 patients only irregular sclerosis without distinct fracture lines was present in 7 of 8 fractures. Of these 4 patients; 3 exhibited intraosseous gas inclusions in a ventral part of a lateral mass; 5 of 8 fractures disclosed a ventral cortical break. When distinct fracture lines had developed in 1 patient, intraosseous vacuum phenomenon had disappeared. Fracture lines evolve over weeks to months and show central bone absorption. The fractures can heal as demonstrated in 4 of 6 fractures in 3 patients, can persist over 1 year without significant changes or can progress to pseudoarthrosis with bone destruction similar to neuropathic joint disease. Intraosseous vacuum phenomena can persist to this stage. Intraosseous vacuum phenomenon is recognized as a potential finding in the early stage of sacral insufficiency fracture, which also is true for irregular sclerosis and ventral cortical disruption.

Disposition of 3H-labelled buserelin continuously infused into rats

The disposition of the gonadotropin-releasing hormone (GnRH) agonist buserelin was studied in male rats under conditions of long-term administration. Rats were continuously infused with about 30 pmole [3H]-buserelin/24 h subcutaneously by osmotic minipumps for 4-7 days. After killing the rats, the 3H-activity of the tissues was measured and was found to be highly concentrated (about 10-fold to plasma) only in the pituitary. The daily amounts of 3H-activity excreted in urine and faces were constant over the whole infusion period, suggesting steady state conditions. On a molar basis, of the infused dose of buserelin, 14.8% was found to be excreted into urine as intact peptide, and 16.5, 10.8 and 20.6% as the partial buserelin sequences 1-2, 1-3 and 5-9. It is concluded that the major elimination route of buserelin, constant with time, is glomerular filtration, followed by enzymatic degradation of part of the filtered peptide by kidney tubuli enzymes to the partial sequences 1-2, 1-3 and 5-9, which reflects the proteolytic breakdown of buserelin by kidney membrane peptidases in vitro. Based on the similarities in the pharmacokinetics, in vivo metabolities, and in vitro enzymatic degradabilities among the GnRH agonists that have the native GnRH sequence modified at position 6 with or without additional modification at the C-terminal, the elimination process as shown here for buserelin should also be valid for other GnRH agonists.

Corticotropin-releasing hormone (CRH) receptors in the mesenteric small arteries of rats resemble the (2)-subtype

The potencies of the corticotropin-releasing hormone (CRH) agonistic peptides oCRH, h/rCRH, frog sauvagine, and carp urotensin I and of the antagonistic peptide alpha-helical CRH9-41 were compared in 3 different in vitro assays: (a) receptor binding to rat brain membranes; (b) release of ACTH/beta-endorphin from rat pituitary cells; and (c) relaxation of rat mesenteric small arteries. From their potency profiles, especially from the high potency of sauvagine relative to CRH in the relaxation assay, it is concluded that the receptors mediating the hypotensive action of systemic CRH in vascular smooth muscle are different from those in the pituitary and brain, and may be identical or very similar to the recently cloned new CRH receptor type 2.

Endemic Tyrolean infantile cirrhosis: an ecogenetic disorder

BACKGROUND

138 infants and young children died from an endemic infantile liver cirrhosis in a circumscribed rural area of western Austria between 1900 and 1974. Frequency of the disease peaked between 1930 and 1960. It has disappeared from this area since 1974.

METHODS

Clinical and genetic data on the patients was gathered; pedigrees analysed and ethnographic studies and interviews were undertaken.

FINDINGS

The disease, which was clinically and pathologically indistinguishable from Indian childhood cirrhosis and hepatic copper toxicosis, was transmitted by autosomal recessive inheritance. Cow's milk, contaminated with copper from untinned copper or brass vessels, may have contributed to the development of copper toxicosis. Replacement of untinned copper cooking utensils by modern industrial vessels has eradicated the disease.

INTERPRETATION

Our findings strongly suggest that the endemic Tyrolean childhood cirrhosis-and by analogy non-Wilsonian hepatic copper toxicosis occurring elsewhere-is an ecogenetic disorder requiring the involvement of both genetic and environmental factors for the disease to become manifest.

Sonographic estimation of umbilical coiling index and correlation with Doppler flow characteristics

OBJECTIVE

To quantitate umbilical vascular coiling antenatally, and to correlate the coiling index with Doppler flow characteristics in umbilical vessels.

METHODS

We studied 45 normal term fetuses within 24 hours before delivery. The umbilical coiling index was calculated using sonographic longitudinal views of cord vessels from several segments antenatally, and by dividing the total number of helices by the cord length (in centimeters) postnatally. Doppler flow velocities were obtained from umbilical arteries and vein in each cord. Flow characteristics were correlated with the umbilical coiling index.

RESULTS

The mean (+/- standard deviation) umbilical coiling index was 0.44 +/- 0.11 in the antepartum period and 0.28 +/- 0.08 after birth. Regression analysis showed a significant linear trend (r = 0.71, P < .001). The correlations between sonographic coiling index and umbilical arterial Doppler flow characteristics (mean velocity, pulsatility index, resistance index, and systolic-diastolic ratio) were not significant. The sonographic coiling index was related to time-averaged velocity and flow in the umbilical vein. A good correlation was found between umbilical vein flow and the coiling index, with a significant linear trend (r = 0.59, P < .001).

CONCLUSION

An intrauterine umbilical coiling index can be determined by ultrasound and correlates well with the actual index at birth. The sonographic umbilical coiling index is related to Doppler flow characteristics in the umbilical vein.

Differential expression of calcyclin and its accessible ligands in various types of cutaneous tumors

Calcyclin is the product of a gene that is regulated in dependence of the cell cycle in fibroblasts in vitro. It has recently been proven to be a sialic acid-binding protein in vitro and in the case of mammalian tissues to bind specifically to annexin II, annexin VI, annexin XI, and glyceraldehyde-3-phosphate dehydrogenase in a Ca(2+)-dependent manner. Since calcyclin can be labelled without impairment of its binding activity, it can be employed as a histochemical tool to localize its accessible ligands. Concomitantly, immunohistochemical localization of calcyclin with a specific antibody is warranted. By using histochemical and immunohistochemical techniques, the expression of calcyclin and its accessible binding sites are demonstrated in serial sections of normal skin and benign, pre-cancerous and malignant tumors of the skin, namely in verruca vulgaris, papillary hidradenoma, syringoma, keratoacanthoma, Bowen's disease, squamous cell carcinoma, melanocytic naevi, primary and metastatic malignant melanoma and non-Hodgkin lymphoma (NHL) of the skin. Cytoplasmic and nuclear expression of calcyclin and its ligands is unexceptionally found in normal skin, epithelial tumors and benign melanocytic tumors. Presence of calcyclin and calcyclin-binding sites is detected in more than 80% of tumor cells in the epithelial lesions. In the group of melanomas and lymphomas heterogeneity is obvious. The application of annexin-specific antibodies raises evidence that members of this protein family co-localize with calcyclin in situ to some extent. These findings suggest that calcyclin and accessible calcyclin-binding molecules, like certain annexins, may be differentially regulated in melanomas and lymphomas in contrast to epithelial lesions with presently undefined biological implications.

Detection of human papillomavirus DNA in nongenital seborrhoeic keratoses

The histological similarities of seborrhoeic keratoses and common warts led to the investigation of the possible occurrence of human papillomavirus DNA (HPV-DNA) in a large number of nongenital seborrhoeic keratoses using the in situ hybridization technique. All specimens derived from normal skin (n = 173) were negative for the applied HPV-DNA probe, whereas the HPV genome was detected in 34 of 173 seborrhoeic keratosis specimens (19.65%). Of 34 HPV-positive specimens, 15 contained types 6/11 and 14 types 31/33/35, and 5 showed no positive reaction to the applied types. These results suggest that a considerable percentage of nongenital seborrhoeic keratoses may be related to an HPV infection.