Clinical experience with spirapril in human hypertension

The efficacy and tolerability of spirapril were evaluated in a prospective, multicentre, post-marketing surveillance study on the treatment of arterial hypertension in 5000 patients, most of whom had received a single daily dose of 6 mg spirapril. The study was carried out by internists and general practitioners. In accordance with placebo-controlled clinical trials, spirapril was proven to be a very effective antihypertensive drug, in respect of both the mean reduction in systolic and diastolic blood pressure achieved as well as the responder rate of 89.4% and 85.4% for systolic and diastolic blood pressure, respectively. Efficacy was equally good in single drug treatment and combination treatment. Differentiated evaluation of blood pressure values in respect of the severity of hypertension on the basis of the World Health Organization classification showed a clear relationship between the baseline blood pressure and the reduction in blood pressure. The higher the baseline blood pressure, the more pronounced was the antihypertensive efficacy; a particular reduction in diastolic blood pressure being observed. Tolerability was also good, with an incidence of side effects of only 2.9%. Coughing was observed in only 0.88% of patients. Thus spirapril is seen to be an effective and well-tolerated antihypertensive drug whose efficacy is clearly related to baseline blood pressure and thus is also very effective in the treatment of severe forms of hypertension.

Unraveling the electronic structure of individual photosynthetic pigment-protein complexes

Low-temperature single-molecule spectroscopic techniques were applied to a light-harvesting pigment-protein complex (LH2) from purple photosynthetic bacteria. The properties of the electronically excited states of the two circular assemblies (B800 and B850) of bacteriochlorophyll a (BChl a) pigment molecules in the individual complexes were revealed, without ensemble averaging. The results show that the excited states of the B800 ring of pigments are mainly localized on individual BChl a molecules. In contrast, the absorption of a photon by the B850 ring can be consistently described in terms of an excitation that is completely delocalized over the ring. This property may contribute to the high efficiency of energy transfer in these photosynthetic complexes.

Angiotensin induces inflammatory activation of human vascular smooth muscle cells

Multiple data suggest that the renin-angiotensin system contributes to the pathogenesis of atherosclerosis. The atherogenic effect of the renin-angiotensin system can only in part be explained by the influence of its effector angiotensin II on blood pressure, smooth muscle cell (SMC) growth, or antifibrinolytic activity. Because chronic inflammation of the vessel wall is a hallmark of atherosclerosis, we hypothesized that angiotensin II may elicit inflammatory signals in vascular SMCs. Human vascular SMCs were stimulated with angiotensin. Inflammatory activation was assessed by determination of interleukin-6 (IL-6) release into the culture medium, detection of IL-6 mRNA by RT-PCR, and demonstration of activation of nuclear factor-kappaB in electrophoretic mobility shift assays. Angiotensin II concentration-dependently (1 nmol/L to 1 micromol/L) stimulated IL-6 production by SMCs via activation of the angiotensin II type 1 receptor (demonstrated by the inhibitory action of the receptor antagonist losartan). Angiotensin I increased IL-6 production by SMCs, too. This effect was inhibited by captopril and ramiprilat, suggesting conversion of angiotensin I to angiotensin II by angiotensin-converting enzyme in SMCs. Steady-state mRNA for IL-6 was augmented after stimulation with angiotensin II, suggesting regulation of angiotensin-induced IL-6 release at the pretranslational level. Moreover, the proinflammatory transcription factor nuclear factor-kappaB, which is necessary for transcription of most cytokine genes, was also activated by angiotensin II. Pyrrolidine dithiocarbamate suppressed angiotensin II-induced IL-6 release, a finding compatible with involvement of reactive oxygen species as second messengers in cytokine production mediated by angiotensin. The data demonstrate the ability of angiotensin to elicit an inflammatory response in human vascular SMCs by stimulation of cytokine production and activation of nuclear factor-kappaB. Inflammatory activation of the vessel wall by a dysregulated renin-angiotensin system may contribute to the pathogenesis of atherosclerosis.

Replication and pathogenicity of primer binding site mutants of SL3-3 murine leukemia viruses

Retroviral reverse transcription is primed by a cellular tRNA molecule annealed to an 18-bp primer binding site sequence. The sequence of the primer binding site coincides with that of a negatively acting cis element that mediates transcriptional silencing of murine leukemia virus (MLV) in undifferentiated embryonic cells. In this study we test whether SL3-3 MLV can replicate stably using tRNA primers other than the cognate tRNAPro and analyze the effect of altering the primer binding site sequence to match the 3' end of tRNA1Gln, tRNA3Lys, or tRNA1,2Arg in a mouse pathogenicity model. Contrary to findings from cell culture studies of primer binding site-modified human immunodeficiency virus type 1 and avian retroviruses, our findings were that SL3-3 MLV may stably and efficiently replicate with tRNA primers other than tRNAPro. Although lymphoma induction of the SL3-3 Lys3 mutant was significantly delayed relative to that of the wild-type virus, molecular tumor analysis indicated that all the primer binding site-modified viruses induce T-cell lymphomas similar to those induced by the wild-type virus in terms of frequencies of genomic rearrangements within the T-cell receptor beta-chain, the immunoglobulin kappa light chain, and the c-myc locus. Whereas none of the mutants were found to revert to tRNAPro primer utilization, in two tumors resulting from the injection of the SL3-3 Lys3 mutant the primer binding site was altered to match that of a new primer species, tRNA1,2Lys. In addition, recombination with endogenous viruses resulting in the generation of recombinant viruses carrying a glutamine primer binding site was detected in the majority of the tumors induced by the SL3-3 Lys3 mutant as well as in two tumors induced by wild-type SL3-3 and the SL3-3 Arg1,2 mutant.

Laparoscopic partial pericystectomy of Echinococcus granulosus cysts in the liver

Laparoscopic partial pericystectomy is a promising new therapeutical approach in surgery of hydatid liver disease. In combination with a review of the published results of laparoscopic therapy for hydatid disease the actual relevance of this technique should be defined. Together with our own experience with this technique we evaluated all patients with hydatid liver disease from Echinococcus granulosus published in literature operated either by pericystectomy or by partial pericystectomy. The review was projected as a search over DIMDI data access. This technique is practicable without increasing the risk of intraabdominal spillage of scolices if well-known security criteria are respected. Additional training is not necessary. Laparoscopic treatment of Echinococcus multilocularis is not possible yet, as complicated liver resections may be required for these patients. Hydatid hepatic cysts of E. granulosus however may be operated upon laparoscopically and do not necessarily require open surgery. While working under visual control minimal invasiveness is achievable and post-operative hospital stay can be reduced. This new technique is a feasible method, especially regarding obese patients, but on the other hand it is limited by a laparoscopically inaccessible intrahepatic localization (Segments IVa, VII, VIII and small centrally located cysts).

Glial hyperpolarization upon nerve root stimulation in the leech Hirudo medicinalis

Hyperpolarizing responses in neuropil glial cells evoked by nerve root stimulation were studied in the central nervous system of the leech Hirudo medicinalis using intracellular recording and extracellular stimulation techniques. From a mean resting potential of -60.5 +/- 1.0, the glial membrane was hyperpolarized by -8.6 +/- 0.8 mV, via stimulation of the dorsal posterior nerve root in an isolated ganglion. Nerve root stimulation evoked biphasic or depolarizing responses in glial cells with resting potentials around -70 mV (Rose CR, Deitmer JW. J. Neurophysiol. 73:125-131, 1995). The hyperpolarizing response was reduced by the ionotropic glutamate receptor antagonist CNQX (50 microM) to 58% of its initial amplitude. In 15 mM Ca2+/15 mM Mg(2+)-saline the hyperpolarization was reduced by 44%. The hyperpolarization that persisted in high-divalent cation saline was not affected by CNQX. Bath-applied glutamate (500 microM) and kainate (2 microM) elicited glial hyperpolarizations that were sensitive to CNQX and 10 mM Mg2+/1 mM Ca(2+)-saline. The 5-HT-antagonist methysergide did not affect the hyperpolarizations evoked by nerve root stimulation. The results show that in the leech glial membrane responses to neuronal activity include not only depolarizations, as shown previously, but also hyperpolarizations, which are mediated by direct and indirect neuron-glial communication pathways. In the indirect pathway, glutamate is a transmitter between neurons.

[Insurance expert assessment of traumatic Achilles tendon rupture. A case report]

Achilles tendon ruptures are among of the most frequent tendon ruptures. Usually middle aged men with infrequent sports activity are involved. In most cases histopathology reveals degenerative changes within the tendon. Unusual rupture location and physical signs of trauma should lead one to consider a traumatic origin of the rupture. Traumatic origin can be confirmed by the accident history and physical signs as well as with the histopathology of the rupture site and possibly a tissue section far away the rupture site. This information can be helpful in insurance inquiries.

Treatment of venous outflow stenoses in thigh grafts with Wallstents

OBJECTIVE

We studied the effectiveness of Wallstent deployment to treat elastic femoral and iliac vein stenoses in patients with lower extremity hemodialysis grafts.

MATERIALS AND METHODS

Between August 31, 1992, and October 13, 1997, 44 metallic stents were deployed in 20 patients to treat stenoses exhibiting immediate, significant elastic recoil after angioplasty. Twenty-four stents were placed in the femoral and saphenous veins, and the remaining 20 stents were placed in the iliac veins. Follow-up was provided by the nephrology and surgical service at our institution and by electronic review of patients' charts. The follow-up period was from August 31, 1992, until October 1, 1998.

RESULTS

Stents were successfully inserted and stenotic lesions dilated in 100% of procedures. Each patient successfully completed at least one session of dialysis after the procedure. The primary patency rate of stents was 87% 60 days after the procedure, 51% 180 days after, 39% 1 year after, and 20% 2 years after. The secondary patency rate was 95% 60 days after the procedure, 92% 180 days after, 81% 1 year after, and 62% 2 years after. Complications were limited to two graft infections that developed 5 and 7 days after stent placement.

CONCLUSION

Treatment of elastic venous stenoses is effective in patients with lower extremity dialysis grafts using metallic stents. The patency rates of these devices placed in the iliac and femoral veins are comparable with those of metallic stents placed in upper extremity and central veins.

[Classical swine fever in wild boars in Switzerland]

In May 1998, wild boars with classical swine fever (CSF) symptoms were detected in the southern part (Canton Ticino) of Switzerland. CSF virus was isolated from the submitted samples and RT-PCR followed by direct nucleotide sequencing of the 5' non-translated region showed that this virus was identical to the isolate previously recognized in wild boars from the area of Varese (Italy). In most animals, antibodies to CSF virus were detected as well. An immediate measurement was taken by limiting the movement of pigs and identifying both risk and surveillance zones. In order not to disturb potentially infected wild boars within their habitat a complete hunting prohibition for 2 months was enforced. The different possibilities of the control of CSF outbreaks in wild boars are discussed.

[Possibilities of avoiding an intra-femoral increase in pressure during hip revision surgery]

An earlier experimental study carried out by us revealed an increase in intrafemoral pressure during removal of cement in hip revision arthroplasty. This increase is greater while removing cement from the distal femoral shaft. Maximum pressure increases occurred while removing the medullary plug (cement stopper), and the measured pressure of more than 150 mmHg is associated with an increased risk of fat embolism. The present study shows that this phenomenon can be avoided through the use of cannulated instruments.

Workflow management systems--a powerful means to integrate radiologic processes and application systems

This presentation describes a research project investigating the suitability of model-based Workflow Management Systems (WfMS) to support radiological process. The following aspects are covered: process modeling, process enactment, and architecture of workflow-enabled application systems.

Suppression of T1-receptor expression by antisense RNA abrogates differentiation of osteogenic osteosarcoma cells

Soluble and membrane-associated variants of the orphan T1-receptor, a homolog of interleukin-1 receptor type I, are expressed in proliferating preosteoblasts in differentiating bone. Recent evidence reveals that T1-receptor synthesis is retained in osteogenic osteosarcoma cells. Here we report that the suppression of T1-receptor expression by mouse osteosarcoma cells using a T1 -antisense expression vector results in the abrogation of the osteogenic potential of the tumor cells. T1-antisense-expressing tumor cells formed anaplastic tumors in vivo and failed to express the osteoblast-specific genes collagen type 1, alkaline phosphatase, and osteocalcin when cultured in a 3-dimensional collagen type I matrix in vitro. Suppression of T1-receptor synthesis did not affect the expression of the essential bone cell-specific transcription factor AML3/CBFA1 in the osteosarcoma cells. These data provide the first evidence that T1-receptor plays a key role in osteogenic differentiation.

Posttraumatic hypertension secondary to adrenal hemorrhage mimicking pheochromocytoma: case report

We report the case of a 68-year-old man who presented with a mass 3 x 4 cm in size located in the right adrenal gland together with extreme hypertension, tripled urine levels for normetanephrine, and normal plasmatic levels of metanephrines. The patient had suffered a fall from a height of 2.5 meters before hospitalization. [123I]MIBG-scan was repeatedly positive in the area of the right adrenal gland. At laparotomy under alpha-adrenergic blocking agents, the suspected pheochromocytoma was histologically confirmed as hematoma. After resection of the adrenal gland, blood pressure returned to normal without drug therapy as did metanephrine levels in urine. Although adrenal insufficiency after distension of the gland caused by hemorrhage has been reported, there are no data available regarding the mimicking of a hormonally active pheochromocytoma. We conclude that intra-adrenal pressure rise caused by hematoma may cause partial ischemic necrosis to the gland but may also induce reactive hyperplasia with periodic excessive secretion of catecholamines. This interpretation is consistent with the finding that plasma levels of catecholamines were normal in contrast to the urinary normetanephrines in the presented case. It might be worthwhile to investigate patients with intra-adrenal hemorrhage immediately after sustaining multiple injuries and in the posttraumatic course of several months up to 1 or more years together with verification of abnormal urinary excretion of metanephrines as a sign of impaired adrenal function.

Angiotensin II activates the proinflammatory transcription factor nuclear factor-kappaB in human monocytes

The renin-angiotensin system may contribute to the pathogenesis of atherosclerosis. A common feature of all stages of atherosclerosis is inflammation of the vessel wall. The transcription factor nuclear factor-kappaB (NF-kappaB) participates in most signaling pathways involved in inflammation. This study therefore examined the effect of angiotensin (ANG) II on NF-kappaB activation in monocytic cells, a major cellular component of human atheroma, by electrophoretic mobility shift assay. ANG II, like TNFalpha, caused rapid activation of NF-kappaB in human mononuclear cells isolated from peripheral blood by Ficoll density gradient. This ANG II effect was blocked by the angiotensin AT1 receptor antagonist losartan. Specificity of ANG II-induced NF-kappaB activation was ascertained by supershift and competition experiments. Moreover, ANG II stimulated NF-kappaB activation in human monocytes, but not in lymphocytes from the same preparation. Together, the data demonstrate the ability of the vasoactive peptide ANG II to activate inflammatory pathways in human monocytes.

Trypsinogen activation peptides (TAP) in peritoneal fluid as predictors of late histopathologic injury in necrotizing pancreatitis of the rat

The levels of trypsinogen activation peptides (TAP) were quantified by ELISA immunoassay in acute pancreatitis of the rat and compared to the degree of late histopathological sequelae and exocrine functional impairment 4 and 12 weeks after the acute phase of the disease. For this purpose acute pancreatitis of different severity was induced using a suitable rat model recently described. Forty five surviving animals were studied. The level of TAP in peritoneal exudate measured 3 and 6 hr after pancreatitis induction correlated well with the amount of the late histopathological injury at the end of the corresponding observation period (at 4 weeks after 3 hr: r = 0.75, P = 0.003, after 6 hr: r = 0.72, P = 0.005, Pearson; and at 12 weeks after 3 hr: r = 0.86, P = 0.0001, after 6 hr: r = 0.84, P = 0.0001, Pearson). A negative correlation of TAP with the impairment of exocrine function was found only at 4 weeks for the secretion of total protein (r = -0.76 after 3 hr; r = -0.62 after 6 hr) and for exocrine function (r = -0.67 after 3 hr, r = -0.57 after 6 hr), but not at 12 weeks after acute pancreatitis. No correlation with plasma amylase and lipase was found. We conclude that quantitation of TAP in ascites provides an accurate prediction of late histopathologic sequelae. Pancreatic exocrine function could be predicted by TAP assay only in the early stage after pancreatitis induction (eg, four weeks). In later stages of the disease (eg, 12 weeks) remaining pancreatic tissue seems to compensate for any exocrine deficits that have occurred.

Management of acute submacular hemorrhage using recombinant tissue plasminogen activator and gas

PURPOSE

To assess the effects of intravitreal injection of recombinant tissue plasminogen activator (rTPA) and gas on submacular hemorrhage in age-related macular degeneration (ARMD).

METHODS

Eleven consecutive patients (11 eyes) with subretinal hemorrhage due to ARMD involving the fovea with elevation of the neurosensory retina were included in this study. Subretinal hemorrhage occured 12 h to 14 days before onset of therapy. Injection of rTPA through the pars plana in a dose of 50 or 100 microg was performed. Gas instillation (0.2-0.4 ml) followed rTPA injection, either immediately after injection (7 patients) or during the following day (4 patients).

RESULTS

After intravitreal injection of rTPA, subretinal clots were totally or partially liquefied when treatment started up to 3 days after onset of bleeding. In all patients treated with 100 microg rTPA a large exudative retinal detachment of the inferior retina resulted, which reabsorbed spontaneously within 2 weeks. After reattachment of the exudative retinal detachment hyperpigmentation of the retinal pigment epithelium was noted. Temporary opacification of the vitreous was observed between the 2nd and 7th postoperative day in 5 eyes (45.5%). Postoperative visual acuity increased in 5 patients (45.5%).

CONCLUSION

Intravitreal application of rTPA followed by gas injection is a sufficient and convenient technique for effective removal of freshly formed submacular hemorrhage. Removal is mediated through combined enzymatic (rTPA) and mechanical (gas) effects. This technique offers a quick recovery of vision in eyes with less severe ARMD.

Improved glucose tolerance in rats treated with the dipeptidyl peptidase IV (CD26) inhibitor Ile-thiazolidide

The incretins glucose-dependent insulinotropic polypeptide (GIP1-42) and truncated forms of glucagon-like peptide-1 (GLP-1) are hormones released from the gut in response to ingested nutrients, which act on the pancreas to potentiate glucose-induced insulin secretion. These hormones are rapidly inactivated by the circulating enzyme dipeptidyl peptidase IV ([DPIV] CD26). This study describes the effect on glucose tolerance and insulin secretion of inhibiting endogenous DPIV in the rat using Ile-thiazolidide, a specific DPIV inhibitor. High-performance liquid chromatography (HPLC) analysis of plasma following in vivo administration of 125I-labeled peptides showed that inhibition of DPIV by about 70% prevented the degradation of 90.0% of injected 125I-GLP-17-36 after 5 minutes, while only 13.4% remained unhydrolyzed in rats not treated with the DPIV-inhibiting agent after only 2 minutes. Ile-thiazolidide treatment also increased the circulating half-life of intact GLP-17-36 released in response to intraduodenal (ID) glucose (as measured by N-terminal specific radioimmunoassay [RIA]). In addition, inhibition of DPIV in vivo resulted in an earlier increase and peak of plasma insulin and a more rapid clearance of blood glucose in response to ID glucose challenge. When considered with the HPLC data, these results suggest that the altered insulin profile is an incretin-mediated response. DPIV inhibition resulting in improved glucose tolerance may have therapeutic potential for the management of type 2 diabetes mellitus.