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During the recent pandemic with the severe acute respiratory syndrome-corona virus‑2 the first messenger ribonucleic acid (mRNA) vaccines were approved. To facilitate mass vaccination, confidence of the general population in these new vaccines is mandatory, which is in turn strongly dependent on the availability of reliable data on complications.Summary of the current knowledge on mRNA vaccination-associated myocarditis as a potentially fatal side effect.Systematic literature review.Diagnostic algorithm for the postmortem diagnosis of mRNA vaccination-associated myocarditis.Autopsy series of fatalities following mRNA SARS-CoV‑2 vaccination up to 6 weeks with subsequent sophisticated and interdisciplinary work-up are necessary to complement clinical data on vaccination-associated myocarditis, especially regarding the incidence of fatal courses.The online version of this article (10.1007/s00194-022-00587-9) includes a PDF file with supplemental clinical features.Mit der aktuellen Pandemie mit dem severe acute respiratory syndrome-corona virus‑2 (SARS-CoV‑2) wurden die ersten messenger Ribonukleinsäure (mRNA)-Impfstoffe zugelassen. Der Erfolg der Impfkampagne hängt vom Vertrauen der Bevölkerung in die neuen Impfstoffe, und dieses wiederum von der Verfügbarkeit reliabler Daten zu Komplikationen ab.Zusammenfassung des aktuellen Kenntnisstandes zu impfassoziierten Myokarditiden, als potenziell letalen Nebenwirkungen der mRNA-Impfstoffe.Systematischer Literatur-Review.Diagnostischer Algorithmus zur systematischen postmortalen Aufarbeitung von Todesfällen im zeitlichen Zusammenhang mit einer mRNA-Impfung hinsichtlich einer impfassoziierten Myokarditis.Die impfassoziierte Myokarditis ist eine Ausschlussdiagnose, die lediglich durch eine differenzierte und interdisziplinäre Aufarbeitung gestellt werden kann. Autopsieserien von Todesfällen bis zu 6 Wochen nach der Impfung sind erforderlich, um die klinischen Daten hinsichtlich letaler Komplikationen zu ergänzen.

Purpose This article presents a novel concept of the evolution and, thus, the pathogenesis of uterine adenomyosis as well as peritoneal and peripheral endometriosis. Presently, no unifying denomination of this nosological entity exists. Methods An extensive search of the literature on primate evolution was performed. This included comparative functional morphology with special focus on the evolution of the birthing process that fundamentally differs between the haplorrhine primates and most of the other eutherian mammals. The data were correlated with the results of own research on the pathophysiology of human archimetrosis and with the extant presentation of the disease. Results The term Archimetrosis is suggested as a denomination of the nosological entity. Archimetrosis occurs in human females and also in subhuman primates. There are common features in the reproductive process of haplorrhine primates such as spontaneous ovulation and corpus luteum formation, spontaneous decidualization and menstruation. These have fused Müllerian ducts resulting in a uterus simplex. Following a usually singleton pregnancy, the fetus is delivered in the skull position. Some of these features are shared by other mammals, but not in that simultaneous fashion. In haplorrhine primates, with the stratum vasculare, a new myometrial layer has evolved during the time of the Cretaceous–Terrestrial Revolution (KTR) that subserves expulsion of the conceptus and externalization of menstrual debris in non-conceptive cycles. Hypercontractility of this layer has evolved as an advantage with respect to the survival of the mother and the birth of a living child during delivery and may be experienced as primary dysmenorrhea during menstruation. It may result in tissue injury by the sheer power of the contractions and possibly by the associated uterine ischemia. Moreover, the lesions at extra-uterine sites appear to be maintained by biomechanical stress. Conclusions Since the pathogenesis of archimetrosis is connected with the evolution of the stratum vasculare, tissue injury and repair (TIAR) turns out to be the most parsimonious explanation for the development of the disease based on clinical, experimental and evolutionary evidence. Furthermore, a careful analysis of the published clinical data suggests that, in the risk population with uterine hypercontractility, the disease develops with a yet to be defined latency phase after the onset of the biomechanical injury. This opens a new avenue of prevention of the disease in potentially affected women that we consider to be primarily highly fertile.

Background The objective of this study was to identify parameters of prognostic relevance in patients presenting with chronic left ventricular dysfunction who underwent endomyocardial biopsy. Materials and methods A total of 351 consecutive patients (age 47·7 ± 12·6 years, 281 male) with a chronic left ventricular dysfunction were enrolled. Endomyocardial biopsies were analysed by histopathology according to Dallas criteria and immunohistological WHO criteria. Virus genome was detected by polymerase chain reaction. The combined end point was time to death or heart transplantation. Results About 19% of patients (n = 67) showed positive Dallas criteria and 39% (n = 118) immunohistochemical signs of inflammation. Viral genome was present in 58% (n = 155). During follow-up, 25% (n = 89; 76 death, 13 HTx) reached the end point. Dallas-positive histopathology (hazard ratio: 0·42; 95% CI: 0·29–0·84, P = 0·031), ejection fraction (hazard ratio: 0·97; 95% CI: 0·94–0·99, P = 0·019) and β-blocker therapy (hazard ratio: 0·41; 95% CI: 0·23–0·69, P = 0·003) were independent outcome predictors. For patients under β-blocker therapy, Dallas-positive histopathology (hazard ratio: 0·37; 95% CI: 0·25–0·76, P = 0·009) and NYHA class III and class IV (hazard ratio: 2·11; 95% CI: 1·04–3·12, P = 0·006) were independent predictors. Conclusions For patients with a chronic left ventricular dysfunction, Dallas-positive histopathology, β-blocker therapy and left ventricular ejection fraction are the most striking parameters for outcome prediction.

Aims Dendritic cells (DCs) are sentinels of the immune system—their role in myocardial disease is unknown as yet. We investigated their myocardial presence in human dilated cardiomyopathy (DCM). Methods and results Endomyocardial biopsies from 72 patients with DCM (EF ∼30%), as well as myocardial specimens from 18 suicide or accident victims were immunohistochemically analysed for myeloid and plasmacytoid DCs, antigen-presenting cells (APCs), and other leucocytes; also tissue fibrosis and apoptosis were histologically quantified. The myocardial viral genome was identified through polymerase chain reaction, and patients underwent clinical follow-up in 3–6 months. We found myocardial DCs of all examined subtypes and maturation stages (fascin, CD11c, CD209, CD83, and CD304), as well as markers for APCs (HLA-DR and CD40) and T-cell activation (CD69) to be significantly decreased in DCM compared with controls. In contrast, regulatory T cells (the GITR epitope), apoptosis (by TUNEL reaction and immunostaining with BCL-2), and a DC chemokine receptor (CCR7) were overexpressed, while no significant differences were observed for macrophages (CD68). Immature myeloid and plasmacytoid DCs strongly correlated with endothelial progenitor cells (CD34), which were similarly reduced in DCM, and inversely correlated with fibrosis. Myeloid DCs were especially reduced in virus-positive biopsies, and their numbers correlated with positive change in EF (ΔEF) at follow-up. Conclusion Myocardial DCs are reduced in heart biopsies of symptomatic DCM patients. Such a reduction correlates with an unfavourable short-term outcome in terms of EF, and could result from myocardial tissue damage, cellular death, and insufficient vascularization in chronic heart failure.

The structure activity relationship of N'-benzylidene-benzohydrazide (NBB) binding to tau and paired helical filament (PHF) proteins as well as amyloid-β₁₋₄₂ fibrils indicate differential selectivity for these protein aggregates. The ability of the compounds to stain neurofibrillary tangles and senile plaques isolated from human AD brain was investigated histochemically. These studies resulted in several tau-PHF and amyloid-β₁₋₄₂ fibril selective ligands respectively. Supported by these results, we rationalized a model for the design of selective ligands for tau, PHF, and amyloid-β₁₋₄₂ fibrils.

Cardiac disease is a major contributor to disease-related death in Churg-Strauss syndrome (CSS). We conducted the current study to determine the prevalence and clinical impact of cardiac involvement in CSS patients. We performed a multicenter, cross-sectional analysis of patients diagnosed with CSS. Cardiac workup included electrocardiography, echocardiography, cardiac magnetic resonance imaging (MRI), and endomyocardial biopsy.We analyzed 49 patients with CSS: 22 patients had clinical evidence of cardiac involvement. A negative antineutrophil cytoplasmic antibodies (ANCA) test and much higher eosinophil counts (9947 vs. 3657/microL, respectively, p < 0.001) distinguished patients with cardiac involvement from those without. Impaired left ventricular function (50%), mild to severe valvular insufficiencies (73%), and pericardial effusions (41%) were common findings in these patients. Endomyocarditis was found in 13 patients (59%) as detected by cardiac MRI, cardiac thrombus formation, and endomyocardial biopsy, and was associated with impaired cardiac function. After a mean follow-up of 47 months, most patients had regained or maintained good cardiac function. However, patients with endomyocarditis had a more severe outcome. Two patients died (61 and 99 mo after diagnosis, respectively), both due to severe cardiomyopathy and heart failure.Cardiac involvement is common in patients with CSS and is associated with the absence of ANCA and high eosinophil counts. Endomyocarditis may represent the most severe manifestation eventually causing fatal outcome. A structured clinical assessment incorporating cardiac imaging with echocardiography and MRI can identify impaired cardiac function and endomyocardial abnormalities.

Because serum Procalcitonin is reported to be a valid postmortem marker of sepsis, this prospective study was carried out to determine whether the semi-quantitative PCT-Q((R))-Test (B.R.A.H.M.S., Germany) is a reliable indicator of postmortem Procalcitonin (PCT) serum levels, thus enabling a quick "tableside" diagnosis of sepsis. Postmortem PCT-levels of 70 forensic and 78 clinical-pathological autopsy cases (n=148) were examined using the B.R.A.H.M.S-PCT-Q-Test during autopsy. 27 cases were categorized as the cases of sepsis according to the ACCP/SCCM Consensus Conference criteria. 121 cases were assigned to the non-sepsis group. Among the 148 cases, 18 samples could not be analyzed by the reason of strong hemolysis. Using a cut-off point of 2 ng/ml, 20 cases of sepsis were identified (true positive) whereas 3 cases of sepsis were not detected (false negative). In the non-sepsis group (107 cases) 6 cases showed a positive testing (false positive). When applied within 48 h postmortem, the PCT-Q-Test showed a sensitivity of 86.96% and a specificity of 94.39% (at cut-off 2 ng/ml). Likelihood ratios and positive predictive values proved to be lower in the forensic autopsy group (PPV: 59.3% in forensic case vs. 85.1% in clinicopathological cases; NPV: 98.73% in forensic cases vs. 95.2% in clinicopathological cases). The PPVs using a cut-off point of 10 ng/ml were 100% in both groups independent of sepsis prevalences. The results show, that a high NPV for prevalences ranging from 3% to 30% can be reached using a 2 ng/ml cut-off point, whereas a cut-off of 10 ng/ml ensures a high PPV for the respective prevalences in the absence of exclusion criteria. The study provides strong evidence that the introduction of rapid diagnostic test (RDTs) of postmortem PCT serum levels may be useful in achieving rapid distinction between sepsis and non-sepsis-related causes of death, especially in conjunction with the medical case history and further autopsy results. In addition, the use of RDTs enables clinicians to conduct an evidence-based validation of clinical diagnosis, thus facilitating future clinical decision-making.

In 37 patients with typical exercise-dependent angina pectoris but with normal coronary arteriograms and normal left ventricular function at rest (X syndrome), the dipyridamole-induced dilatory reserve of the coronary vascular system was reduced significantly to about 50% of control values (P less than 0.001). There were no changes in the small vessels causing the reduced dilatory reserve, but ultrastructural changes in the mitochondria were demonstrable. In the patients with X syndrome there was a significant reduction of lactate extraction (P less than 0.05) after electrical atrial stimulation (150/min) and in most cases lactate production was demonstrable. In the control group the myocardial lactate uptake was unchanged. Left ventricular function in patients with X syndrome was normal at rest whereas during exercise it was significantly reduced (P less than 0.001). These results show that X syndrome consists of a particular form of ischaemic heart disease with still normal left ventricular function at rest, but disordered pump activity during physical stress.

Basic fibroblast growth factor (FGF2) plays a major role in angiogenesis and capillary growth. In contrast to vascular endothelial growth factor, which is required for proliferation and survival of endothelial cells, FGF2 does not seem to be essential since the Fgf2 knockout is not lethal. Therefore, the precise genetic and physiological roles of FGF2 for capillary development and adaptation remain to be determined. Here we show that myocardial capillary supply is normal at birth, but significantly reduced by approximately 25% in adult Fgf2+/- and Fgf2-/- mice as compared with wild-type littermates. In contrast, after induction of myocardial hypertrophy by continuous infusion of angiotensin II (ANG II) for 6 days marked capillary growth was seen in both Fgf2+/- and Fgf2-/- mice, but not in wild-type littermates. These data demonstrate that two intact Fgf2 genes are necessary for normal capillary development after birth, whereas FGF2 seems to be dispensable for adaptive myocardial capillary growth in the adult mouse.

Zusammenfassung Das Krankheitsbild des genitalen Lichen sclerosus der Frau ist sowohl klinisch als auch histologisch eindeutig definiert. Dabei bleibt festzustellen, das neben dem haufigeren klassischen Lichen sclerosus, der zu einer straffen Atrophie fuhrt, auch eine Form mit persistierenden Plaques existiert, welche histologisch durch eine Stachelzellhyperplasie gekennzeichnet ist. Die Atiologie ist bis heute nicht geklart, wobei eine Autoimmunkrankheit am wahrscheinlichsten ist, wahrend infektiose und hormonelle Faktoren wohl keine Rolle spielen. Die Beschreibung eines Stachelzellkarzinoms im Bereich eines genitalen Lichen sclerosus wirft erneut die Frage auf, inwieweit der Lichen sclerosus als Prakanzerose zu werten ist. Aufgrund dieser doch selten in der dermatologischen Literatur beschriebenen Assoziation, mus ein Zusammenhang eher verneint werden. Im gynakologischen Krankengut werden allerdings wesentlich hohere Zahlen angegeben, weil die Autoren von Patientinnen mit Vulvakarzinomen ausgehen und nach histologischen Kriterien des Lichen sclerosus gefahndet haben. Ohne entsprechendes klinisches Korrelat des Lichen sclerosus ist eine derartige Assoziation aber nicht zulassig, so das der klassische genitale Lichen sclerosus nicht als Prakanzerose bezeichnet werden kann. Auf dem Boden der hypertrophen Form des Lichen sclerosus ist die Entstehung von Stachelzellkarzinomen mit einer Haufigkeit von 3 – 5 % allerdings moglich. Summary Genital lichen sclerosus in women is a clinically and histologically well defined disease. In addition to the classical atrophic form, there is a hypertrophic variant, which is characterised histologically by squamous cell hyperplasia. The aetiology is unknown but an autoimmune pathogenesis seems most likely. Infectious or hormonal influences do not play a major role. We describe a squamous cell carcinoma of the vulva with a co-existing lichen sclerosus. This case raises again the question of a precancerous potential of lichen sclerosus. In the dermatological literature, only a few cases with association of lichen sclerosus and squamous cell carcinoma are known. This is in contrast to gynaecological literature, where a high number of squamous cell carcinomas has been described. Gynaecologists search for the histological findings of lichen sclerosus adjacent to squamous cell carcinoma. Such an attempt is not valid without the clinical signs of lichen sclerosus, so that indeed classical lichen sclerosus does not seen to be a precancerous lesion. On the other hand, the hypertrophic form of lichen sclerosus seems to be associated with squamous cell carcinoma in about 3 – 5 % of case.

Cardiomyocyte loss in experimental renal failure: Prevention by ramipril.BackgroundThe development of left ventricular hypertrophy (LVH) and of structural abnormalities of the heart is a key abnormality in renal failure that potentially contributes to the high rate of cardiac death. In renal failure, the behavior of cardiomyocyte volume and number in the development of LVH has so far not been investigated. A potential role of the (local) renin-angiotensin system (RAS) in the genesis of LVH has been suspected. It was the aim of the present study in short-term experimental renal failure (1) to characterize cardiomyocyte volume and number and (2) to study whether they are affected by the angiotensin-converting enzyme (ACE) inhibitor ramipril.MethodsSprague-Dawley rats (N = 8 to 10 per group) had a subtotal nephrectomy (SNX) or sham operation and followed for 8 weeks. One SNX group received the ACE inhibitor ramipril (0.5 mg/kg body weight) in the drinking fluid. After perfusion fixation, the morphology of the heart was investigated using stereologic techniques.ResultsSystolic blood pressure was slightly, but not significantly, higher in untreated SNX, but the left ventricular (LV) weight and LV weight/body weight ratio (2.32 ± 0.20 mg/g) were significantly higher in SNX than in sham-operated animals (1.90 ± 0.16 mg/g). Sarcomeric length was not significantly different between SNX and sham-operated animals. There was an increase in the number of terminal deoxynucleotidyl transferase-mediated uridine triphosphate nick end labeling (TUNEL)-positive myocytes in SNX compared to sham-operated animals and a significant increase in cardiomyocyte volume (15,713 ± 4557 μm3 vs. 10,067 ± 2242 μm3, P < 0.01) as well as a decrease of cardiomyocyte numbers per unit myocardial volume (61.2 ± 16.2 vs. 92.2 ± 20.9 × 103/mm3) and per left ventricle (70.9 ± 16.5 × 106 vs. 94.8 ± 18.1 × 106, P < 0.05). Both abnormalities were abrogated by treatment with ramipril (6347 ± 972.4 μm3 and 106 ± 18.9 103/mm3 or 118 ± 39.5 × 106, respectively), which also completely prevented the increase in LV weight/body weight ratio (1.83 ± 0.14 mg/g).ConclusionLVH in renal failure is characterized by cardiomyocyte hypertrophy, but also cardiomyocyte drop out. A role of the RAS is suggested by the beneficial effect of ramipril treatment that is not accounted for by differences in blood pressure.

Left ventricular hypertrophy (LVH) develops very early in experimental renovascular hypertension after clipping of one renal artery and is accompanied by a remodeling of cardiac structure which has not yet been investigated in detail. It was the aim of the present study to analyze changes in cardiomyocyte number and volume in LVH after 2 weeks of renovascular hypertension. Sprague-Dawley rats were subjected to clipping of the left renal artery (2K1C) or sham operation (sham). One group of 2K1C rats received antihypertensive treatment with dihydralazine. The experiment was terminated after 2 weeks. Hearts were investigated using stereological methods, electron microscopy, immunohistology for the proliferation marker proliferating cell nuclear antigen, the pro- and anti-apoptotic proteins Bax and Bcl-2 as well as the TUNEL technique. After 2 weeks, systolic blood pressure and relative left ventricular weight were significantly higher in untreated 2K1C animals than in sham and dihydralazine-treated 2K1C rats. Volume fraction of interstitial tissue and capillary length density were not different, whereas wall thickness of intramyocardial arteries was significantly higher in untreated 2K1C (5.12+/-0.7 micro m) than in sham (3.92+/-0.6 micro m) and in dihydralazine-treated 2K1C (3.91+/-0.7 micro m) rats. Cardiomyocyte diameter and volume were significantly higher in untreated 2K1C than in sham animals. The number of cardiomyocytes per left ventricle was significantly lower in untreated 2K1C rats (5.5+/-1.6 vs 3.9+/-6.9 x10(7)). Using immunohistochemistry, no direct evidence of apoptosis was found, but a relative higher expression of the anti-apoptotic protein bcl-2 expression was seen in untreated 2K1C than in sham animals. This may reflect a protective mechanism as a consequence of earlier occurring apoptosis. These observations document that experimental renovascular hypertension induces a rapidly developing LVH characterized by marked cardiac remodeling and substantial loss of cadiomyocytes.

Cardiac remodelling with interstitial fibrosis in renal failure, which so far is only poorly understood on the molecular level, was investigated in the rat model by a global gene expression profiling analysis. Sprague–Dawley rats were subjected to subtotal nephrectomy (SNX) or sham operation (sham) and followed for 2 and 12 weeks, respectively. Heart-specific gene expression profiling, with RZPD Rat Unigene-1 cDNA arrays containing about 27 000 gene and EST sequences revealed substantial changes in gene expression in SNX compared to sham animals. Motor protein genes, growth and differentiation markers, and extracellular matrix genes were upregulated in SNX rats. Obviously, not only genes involved in cardiomyocyte hypertrophy, but also genes involved in the expansion of non-vascular interstitial tissue are activated very early in animals with renal failure. Together with earlier findings in the SNX model, the present data suggest the hypothesis that the local renin–angiotensin system (RAS) may be activated by at least two pathways: (a) via second messengers and Gproteins (short-term signalling); and (b) via motor proteins, actins and integrins (longterm signalling). The study documents that complex hybridization analysis yields reproducible and promising results of patterns of gene activation pointing to signalling pathways involved in cardiac remodelling in renal failure. The complete array data are available via http://www.rzpd.de/cgi-bin/services/exp/viewExpressionData.pl.cgi

Objective: Prostaglandin E1 (PGE-1) is a potent vasodilative agent which has been used to bridge patients with chronic heart failure listed for heart transplantation (HTX). In various experimental settings PGE-1 appears to stimulate angiogenesis by inducing vascular endothelial growth factor expression. This observational clinical study sought to investigate the angiogenic effects of PGE-1 in the failing human heart. Methods: Neovascularization was investigated in 14 explanted hearts from patients with ischemic cardiomyopathy (ICMP) who had been bridged to HTX with PGE-1 (8±1 mg/kg/min, 97±75.6 days) and compared with 14 hearts who did not receive PGE-1 prior to HTX. In three sectional areas obtained from the left ventricular wall CD34, von Willebrand factor (vWf), nuclear Ki67 (MIB-1), and VEGF were quantified by immunohistochemistry to estimate capillary density and endothelial cell proliferation. Additionally, to investigate a possible angiogenic effect of PGE-1 in vitro, cultured human coronary artery smooth muscle cells (HCASMCs) were treated with PGE-1. Results: PGE-1-treated patients had significantly more CD34- and vWf-positive cells in the subepicardium (both P

In the heart of uremic animals and patients, the number of capillaries per volume of myocardium is reduced. Immunohistochemical studies demonstrated increased cardiac endothelin-1 (ET-1) expression in the left ventricle of uremic animals. Therefore, whether treatment with a selective ET A -receptor antagonist prevented such capillary-myocyte mismatch was investigated. Twenty-four h after subtotal nephrectomy, rats were left untreated or started on treatment with the ET A -receptor antagonist LU 135252 (20 mg/kg per d) and with the angiotensin-converting enzyme (ACE) inhibitor trandolapril (0.3 mg/kg per d), respectively. BP was monitored by telemetry. Myocardial capillary length density was analyzed by stereologic techniques that avoid anisotropy artifacts. In addition, cardiac ET-1 protein and mRNA were measured using immunohistochemistry, in situ hybridization, and quantitative reverse transcription—PCR. Changes in cardiac ET A -and ET B -PCR. receptor mRNA were measured using reverse transcription—PCR. Fifteen wk after subtotal nephrectomy, significantly reduced left ventricular capillary length density (3307 ± 535 mm/mm 3 ) was found compared with sham-operated controls (3995 ± 471 mm/mm 3 ); this was also seen in animals that were treated with trandolapril (3503 ± 533 mm/mm 3 ) but not in animals that were treated with LU 135252 (3800 ± 303 mm/mm 3 ). The results support a role of ET-1 in the genesis of left ventricular capillary/myocyte mismatch in uremia.

A potential role of the sympathetic nervous system in progression of renal failure has received little attention. This study examined whether nonhypotensive doses of moxonidine, an agent that reduces sympathetic activity, affects glomerulosclerosis, urine albumin excretion, and indices of renal handling of norepinephrine (NE) in subtotally nephrectomized (SNX) rats. Sprague Dawley rats were SNX or sham-operated (control). SNX rats were either left untreated or treated with moxonidine in a dose (1.5 mg/kg body wt per d) that did not modify telemetrically monitored 24-h BP. Glomerular and renal morphology were evaluated by quantitative histology, immunohistochemistry, and in situ hybridization. Urine albumin excretion rate was analyzed by enzyme-linked immunosorbent assay, and kidney angiotensin II and NE content were measured using HPLC, (3)H-NE uptake, and release. Body and kidney weight and BP were not significantly different between SNX with or without moxonidine. The glomerulosclerosis index was significantly lower in moxonidine-treated (0.88 +/- 0.09) compared with untreated (1.55 +/- 0.28) SNX rats, as was the index of vascular damage (0.32 +/- 0.14 versus 0.67 +/- 0.16). The number of proliferating cell nuclear antigen-positive glomerular and tubular cells per area was significantly higher in untreated SNX rats than in controls and moxonidine-treated SNX rats. The same was true for urine albumin excretion rate. Renal angiotensin II tissue concentration was not affected by moxonidine. In untreated SNX rats, renal nerve stimulation and exogenous NE induced an increase in isolated kidney perfusion pressure (102 +/- 21 versus 63 +/- 8 mmHg). Renal endogenous NE content was significantly lower in SNX rats than in controls (86 +/- 14 versus 140 +/- 17 pg/mg wet weight). Cortical uptake of [(3)H]-NE was not different, but cortical NE release was significantly higher in SNX rats than in controls. Reduced function of presynaptic inhibitory alpha-adreno-receptors is unlikely because an alpha(2)-adrenoceptor antagonist increased NE release. At subantihypertensive doses, moxonidine ameliorates renal structural and functional damage in SNX animals, possibly through central inhibition of efferent sympathetic nerve traffic. In kidneys of SNX rats, indirect evidence was found for increased activity of a reduced number of nerve fibers.

Ziel der Arbeit ist die Darstellung vaskulitisch bedingter Veranderungen der Arteria carotis interna infolge einer Riesenzellarteriitis (Arteriitis temporalis). Bei zwei von neun zwischen 1996 und 1998 konsekutiv, behandelten Patienten mit histologisch gesicherter Arteriitis temporalis fanden sich angiographisch fur eine Vaskůlitis typische Veranderungen („vascular narrowings”) in proximalen und distalen Abschnitten der Arteria carotis interna mit Einbezug der Abgange der Arteria ophthalmica. Zusatzlich lagen Gefasabbruche und Kaliberschwankungen in terminalen Segmenten der Arteria gyri angularis und Arteria temporooccipitalis vor. Eine Patientin erlitt einen Mediaterritorialinfarkt, parietookzipital. Die angiographischen Befunde legen nahe, das neuroophthalmologische Komplikationen und Hirninfarkte auch durch den Befall mittlerer und terminaler Gefasabschnitte bedingt sein konnen.

We report the case of a 32-year-old man, admitted to cardiac care unit with congestive heart failure, caused by a reduced global cardiac function four months after oral hydrofluoric acid ingestion while attempting suicide. Biopsy results of left ventricular myocardium confirmed toxic myocarditis due to ingestion of hydrofluoric acid. This case represents an uncommon example of toxic myocarditis as a long-term complication of oral hydrofluoric acid ingestion. We recommend cardiological follow-up consultations in patients with hydrofluoric acid intoxication for early detection of cardiac deterioration.

In view of the high rate of cardiac death in renal failure, the factors involved in the genesis of structural changes in the heart are of obvious interest. The present study addresses the issue whether growth factors known to be involved in cardiac remodelling are abnormally expressed in rats with renal failure.Sprague Dawley rats were subjected to binephrectomy (2 days) or subtotal nephrectomy (8 weeks). Controls were sham-operated rats and rats with Goldblatt hypertension. Cardiac expression of proliferating cellular nuclear antigen (PCNA), of growth factors and of their receptors (PDGF, TGF-beta, VEGF) was investigated immunohistochemically. In addition, cardiac PDGF-and TGF-beta mRNA were assessed using quantitative RT-PCR.Eight weeks after subtotal nephrectomy (SNX) significantly increased expression of PCNA and PDGF was found in the cardiac interstitium and of PCNA and VEGF in the walls of intramyocardial arteries. In addition, PCNA-positive cardiomyocytes were noted in SNX. Similar changes were not seen in the hearts of hypertensive controls, i.e. rats with renovascular hypertension, despite slightly higher blood pressure and more pronounced left ventricular hypertrophy (LVH). While significant changes of cardiac PDGF- and TGF-beta mRNA expression could not be documented in the whole-heart homogenates 8 weeks after subtotal nephrectomy, 2 days after bilateral nephrectomy PDGF mRNA was significantly increased and TGF-beta mRNA decreased.The observations demonstrate (i) specific activation of cardiac interstitial cells after SNX, (ii) activation of postmitotic cardiomyocytes, possibly predisposing to apoptosis, (iii) increased expression of PDGF in the cardiac interstitium and in the wall of intramyocardial arteries, (iv) increased expression of VEGF associated with hypertrophy of arterial smooth muscle cells. These results were not explained by elevated blood pressure or LVH, respectively.

Experiments indicate that capillary density is reduced in the hypertrophied left ventricle of rats with subtotal nephrectomy compared to control rats with similar BP and left ventricular hypertrophy, suggesting that in uremia, hypertrophying cardiomyocytes outgrow their capillary supply. No information on myocardial capillary supply in humans is currently available. The hearts of nine dialyzed patients, nine patients with essential hypertension, and 10 normotensive control subjects at postmortem were obtained. Subjects with stenosing coronary lesions and left ventricular pump failure were excluded. Special sampling procedures were used to exclude stereologic artefacts. Capillaries were specifically stained with ulex lectin and analyzed by stereologic techniques. Length density of myocardial capillaries (Lv; mm/mm3) was significantly (P < 0.001) lower in dialyzed patients (1483 +/- 238) than in patients with essential hypertension (1872 +/- 243) or in normotensive control patients (2898 +/- 456). In parallel, myocyte diameter and volume density of myocardial interstitial tissue were significantly (P < 0.001) increased in uremic patients compared to patients with essential hypertension and control patients, respectively. Diminished left ventricular capillary supply in renal failure must increase critical oxygen diffusion distance in the myocardium, thus exposing cardiomyocytes to the risk of hypoxia. It is unknown whether such reduced ischemia tolerance can be reversed by increasing oxygen supply (e.g., by reversing anemia).

Detection of enterovirus RNA in endomyocardial biopsies (EMB) by reverse transcription/polymerase chain reaction (RT-PCR) is currently the preferred diagnostic procedure in suspected enterovirus heart disease (EHD), which can present clinically as myocarditis, dilated cardiomyopathy (DCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC). EMB and peripheral blood mononuclear cells (PBMC) of 44 patients with suspected EHD were examined by nested RT-PCR to investigate whether the myocardial enterovirus infection is limited to the heart or is generalized. Enterovirus RNA was detected in EMB, but not in PBMC, of 8 patients (3 of these suffered from ARVC), whereas EMB of 16 controls and PBMC of 45 controls were negative. In addition, enterovirus RNA was demonstrated in PBMC, but not in EMB, of a single patient with suspected EHD. A high sequence homology of the amplicons to coxsackievirus B3 was demonstrated in 7 patients, and to coxsackievirus B2 in two patients. In order to evaluate whether the myocardial enterovirus infection was acute or persistent, neutralization and complement fixation tests were performed for antibodies against the serotypes indicated by the nucleic acid sequences. Neutralizing antibodies were detected in the sera of all 9 patients, but complement fixing antibodies were demonstrated only in one EHD patient and in the patient positive for enterovirus RNA in PBMC. In conclusion, the molecular and serological data demonstrate that CVB3 predominates as cardiotropic enterovirus, and that the enterovirus replication is limited to the heart in EHD. Serological results support the hypothesis of myocardial enterovirus RNA persistence in spite of neutralizing antibodies.

Cardiovascular complications are a well-known feature of chronic renal failure. Increased wall thickness of intramyocardial arterioles and elastic (aorta) and peripheral (mesenteric) arteries is seen even after normalization of blood pressure. It is currently unknown whether such increases result from hyperplasia of vascular smooth muscle cells, hypertrophy, or a combination of both or from an increase in aortic extracellular matrix. Using a recently developed unbiased stereological technique (the dissector), we investigated the aortas of subtotally nephrectomized rats and sham-operated controls after perfusion fixation. We determined aortic wall thickness, cross-sectional area of aortic media, total number of vascular smooth muscle cells per unit aortic length (1 mm), mean cell and nuclear volumes, volume density of elastic fibers, extracellular matrix, vascular smooth muscle cells, and total volumes of these structures per unit of aortic length (1 mm). Blood pressure was not significantly increased in subtotally nephrectomized rats. In contrast, wall thickness, cross-sectional media, total number of aortic vascular smooth muscle cells, and volume of extracellular matrix including collagen were significantly increased after subtotal nephrectomy, whereas cellular hypertrophy was only modest and an increase in elastic fibers did not occur. In conclusion, increased aortic wall thickness in experimental renal failure results primarily from an increase in aortic extracellular matrix. In addition, however, proliferation of aortic vascular smooth muscle cells resulting in cell hyperplasia also contributed to aortic wall thickening to a minor degree. It appears that aortic wall thickening is caused by secretory stimulation of the proliferating vascular smooth muscle cells, resulting in increased matrix production. The nature of the underlying stimulus requires further investigation.

There is a high demand for the development of an imaging agent for neurofibrillary tangles (NFTs) detection in Alzheimer's diagnosis. In the present study, a series of rhodanine-3-acetic acids was synthesized and evaluated for fluorescence imaging of NFTs in brain tissues of AD patients. Five out of seven probes have shown excellent binding affinity to NFTs over amyloid plaques in the Thiazine red R displacement assay. However, the selectivity in this in vitro assay is not confirmed by the histopathological evaluation, which indicates significant differences in the binding sites in the assays. Probe 6 showed binding affinity (IC50=19nM) to tau aggregates which is the highest among this series. Probes 2, 3, 4 and 5 display IC50 values of lower than 100nM to tau aggregates to displace Thiazine red R. Evaluation of the cytotoxicity of these five probes with human liver carcinoma cells revealed that these compounds excert negligible cytotoxicity. The in vivo studies with zebrafish embryos confirmed negligible cytotoxicity at 24 and 72h post fertilization.

Shedding light on grey matter: Fluorescent trimethine cyanines were evaluated as imaging probes for neurofibrillary tangles in post-mortem brain sections of Alzheimer's disease patients. These probes bind to neurofibrillary tangles with high contrast and selectivity over amyloid β plaques.

Dilated cardiomyopathy (DCM) is associated with heart failure and increased mortality and there is no reliable biomarker to estimate patients' prognosis. During cardiac remodeling, an extensive reorganization of the extracellular matrix occurs. The study was aimed to investigate matrix metalloproteinase 9 (MMP-9), tissue inhibitor of metalloproteinase 1 (TIMP-1) and fetal tenascin-C (B(+) Tn-C) and fibronectin (ED-A(+) Fn) variants known to be involved in that process.In 187 patients with DCM, levels of MMP-9, TIMP-1 and B(+) Tn-C in serum as well as B(+) Tn-C and ED-A(+) Fn in tissue were quantified and subjected to univariate analysis. For all serum markers, concentrations above a calculated threshold were associated with decreased survival (MMP-9: p = 0.008, TIMP-1: p = 0.001, B(+) Tn-C: p0.001) and a significantly higher risk to die or undergo transplantation. In tissue, a reexpression of B(+) Tn-C and ED-A(+) Fn could be shown. Protein deposition levels of ≥4.5% for B(+) Tn-C and ≥2.1% for ED-A(+) Fn were associated with a significantly decreased survival (p = 0.001 for B(+) Tn-C, p = 0.031 for ED-A(+) Fn) and an increased risk to die or undergo transplantation. In a multivariate analysis, TIMP-1 is the superior parameter to predict transplantation free survival (p = 0.027).Serum levels of MMP-9, TIMP-1 and B(+) Tn-C and tissue levels of B(+) Tn-C and ED-A(+) Fn are promising markers for risk assessment. The reoccurrence of ED-A(+) Fn and the availability of a human antibody usable as a vehicle for targeted drug delivery might be the basis for novel therapeutic strategies.

In experimental renal failure, increased intramyocardial arteriolar wall thickness, reduced myocardial capillary density, and increased cardiac interstitium are found. The extent to which such alterations can be modified by therapeutic interventions has not been investigated to date. The purpose of this study was to examine the effects of Ramipril, Nifedipine and Moxonidine on these structural changes. Sham-operated and subtotally nephrectomized (SNX) 300-g male Sprague-Dawley rats (N = 7 to 11) were left untreated (N = 9) or treated with Ramipril (0.5 mg/kg body wt per day; N = 7), Nifedipine (30 mg/kg body wt per day; N = 9), or Moxonidine (10 mg/kg body wt per day; N = 8) for 8 wk. After perfusion fixation, heart and aorta were examined by stereological techniques. Aortic wall thickness was significantly higher in SNX than in sham-operated control rats and was similarly lowered by all three interventions. In contrast, the wall thickness of intramyocardial arterioles was significantly higher in SNX; this was prevented by Ramipril and Nifedipine, but not by Moxonidine. Intramyocardial capillary length density (Lv) was significantly lower and interstitial volume density (Vv) significantly higher in untreated SNX. Reduction of capillary length density was completely prevented by Moxonidine and in part by Ramipril. The increase in cardiac interstitial volume density was completely prevented by Ramipril and was partially prevented by Moxonidine or Nifedipine treatment. The following conclusions can be drawn from the results: (1) all agents normalize aortic wall thickness, but only calcium channel blockers and angiotensin-converting enzyme (ACE) inhibitors prevent intramyocardial arteriolar wall thickening: (2) intramyocardial arteriolar wall thickening, capillary rarefaction, and expansion of the cardiac interstitium are seen in SNX even after lowering the blood pressure to subnormal levels; i.e., changes in systemic blood pressure cannot completely explain the altered vascular structure in renal failure; (3) the effects of Ramipril, Nifedipine, and Moxonidine on cardiovascular structures in experimental renal failure are not completely accounted for by their hemodynamic actions.

Objectives.Endomyocardial biopsy samples from patients with idiopathic dilated cardiomyopathy were screened for the presence of enterovirus genome. Patients with enterovirus-positive samples were further studied with regard to disease course, histologic variables and response to interferon-alpha treatment.Background.Studies of patients with idiopathic dilated cardiomyopathy have reported widely divergent clinical outcomes, suggesting that there is no unique underlying pathogenetic mechanism.Methods.Five left ventricular endomyocardial biopsy samples were screened for the presence of the enterovirus genome by an established in situ hybridization technique in combination with a histologic, histomorphometric and immunohistologic workup. The course of the disease was then prospectively followed for up to 50 months. Virus-positive patients whose condition deteriorated were treated with interferon-alpha.Results.Of 77 patients, 20 (26%) had enterovirus-positive and 57 (74%) enterovirus-negative biopsy samples. During a mean follow-up period of 25.8 ± 13.7 months, 1 patient in the enteroviruspositive group and 11 in the enterovirus-negative group died. Four patients in the enterovirus-negative group underwent heart transplantation (p < 0.05). The surviving 19 enterovirus-positive patients had a decrease in mean left ventricular end-diastolic diameter from 66 to 61 mm (p < 0.05) and a mean increase in left ventricular ejection fraction from 0.35 to 0.43 (p < 0.05). In contrast, enterovirus-negative patients had no significant change in end-diastolic diameter or left ventricular ejection fraction. Four patients in the enterovirus-positive group whose condition deteriorated were treated with a 6-month course of subcutaneous interferon-alpha (3 × 106U every second day). This treatment induced hemodynamic improvement in all four patients and eliminated the persistent enteroviral infection in two.Conclusions.Enterovirus-positive patients have a better heart transplantation-free survival rate and hemodynamic course, with fewer histologic changes, than do enterovirus-negative patients. In addition, enterovirus-positive patients respond favorably to interferon-alpha treatment. These observations indicate that myocardial enteroviral infection with associated left ventricular dysfunction is a distinct disease entity with a benign course.

Background: Alzheimer's disease is characterized by two notorious protein aggregates in the brain: extracellular senile plaques mainly consisting of amyloid-β peptides and tau-protein-derived intracellular paired helical filaments. The diagnosis of Alzheimer's disease is impaired by insufficient sensitivity and specificity of diagnostic methods to visualize these pathological hallmarks over all disease stages. Objective: The established fluorescence marker methoxy-X04 stains plaques, tau tangles and amyloid-derived angiopathies with good specificity, yet it is limited by slow elimination in vivo. Since the need for new markers is high, we prepared methoxy-X04 derivatives and evaluated their potential as imaging agents in Alzheimer's disease pathology. Methods and Results: In this study, we describe an improved synthesis for methoxy-X04 and its derivatives and their affinity determination for the respective protein targets by immunohistology and a displacement assay. Conclusion: This resulted in the identification of new derivatives of methoxy-X04 with improved binding affinity.

Coronary artery anomalies are found in approximately 1.3 % of symptomatic adult patients undergoing coronary arteriography and encompass a wide variety of anatomic patterns. Single coronary arteries are found in 0.024–0.066 % of this group. The particular type of a single coronary artery with an anatomically correct course of either artery (so-called L/R-I type according to the Lipton and Yamanaka/Hobbs classification) is an especially rare phenomenon and has been described for the left coronary artery and for the right coronary artery in adults. In these anomalies an isolated coronary artery ensuring the blood supply of the entire heart displayed a compensatory widening of the lumen. The case of a 6-year-old boy who collapsed during exercise and died subsequently of acute cardiac death is presented. At autopsy a single right coronary artery with an anatomically correct course (R-I type) arising from the right sinus of Valsalva was found. On microscopic examination myocardial calcifications and scars were found in the papillary muscles of the mitral valve. Common ion channel disorders were excluded by DNA analysis. Sudden cardiac death on the basis of chronic ischemic heart disease was ascertained as the cause of death. Autopsy and microscopic findings, as well as aspects of the underlying pathophysiology, are presented and discussed.

The in vivo diagnosis of Alzheimer's disease (AD) is of high socioeconomic interest and remains a demanding field of research. The biopathological hallmarks of the disease are extracellular plaques consisting of aggregated β-amyloid peptides (Aβ) and tau protein derived intracellular tangles. Here we report the synthesis and evaluation of fluorescent pyrazine, pyrimidine,and pyridazine derivatives in vitro and in vivo aiming at a tau-based diagnosis of AD. The probes were pre-evaluated on human brain tissue by fluorescence microscopy and were found to label all known disease-related alterations at high contrast and specificity. To quantify the binding affinity, a new thiazine red displacement assay was developed and selected candidates were toxicologically profiled. The application in transgenic mouse models demonstrated bioavailability and brain permeability for one compound. In the course of histological testing, we discovered an AD-related deposition of tau aggregates in the Bowman's glands of the olfactory epithelium, which holds potential for an endoscopic diagnosis of AD in the olfactory system.

We evaluated 2-styrylindolium derivatives (6-11) as novel and selective probes for neurofibrillary tangles (NFTs) on brain sections of AD patients. The staining experiments indicated that these compounds may bind selectively to NFTs in the presence of s-amyloid (As) plaques. Cell free binding assays confirmed that 2-[2-[4-(1-pyrrolidinyl)phenyl]ethenyl]-1,3,3-trimethyl-3H-indolium iodide (9) and 2-[2-[4-(diethylamino)phenyl]ethenyl]-1-butyl-3,3-dimethyl-3H-indolium iodide (11) display excellent affinities to Tau-aggregates (IC(50) values of 5.1 and 1.4 nM, respectively) in the displacement of Thiazin Red R. These probes have good solubility in distilled water and low or no cytotoxicity in zebrafish embryo and liver hepatocellular carcinoma cell assays.

An association between low nephron number and subsequent development of hypertension in later life has been demonstrated. The underlying pathomechanisms are unknown, but glomerular and postglomerular changes have been discussed. We investigated whether such changes are already present in prehypertensive “glial cell line-derived neurotrophic growth factor” heterozygous mice (GDNF+/−) with lower nephron number. Twenty-six-week-old mice [22 GDNF+/−, 29 C57B6 wild-type control (wt)] were used for in vivo experiments with intra-arterial and tail cuff blood pressure measurements. After perfusion fixation, kidneys were investigated with morphological, morphometric, stereological, and immunohistochemical techniques and TaqMan PCR analysis. As expected at this age, blood pressure was comparable between GDNF+/− and wt. Nephron number per kidney was significantly lower in GDNF+/− than in wt (−32.8%, P < 0.005), and mean glomerular volume was significantly higher (+49.5%, P < 0.001). Renal damage scores, glomerular and tubular proliferation, analysis of intrarenal arteries and peritubular capillaries, expression of relevant tubular transporter proteins, as well as gene expression of profibrotic, proinflammatory, or prohypertensive markers were not significantly different between GDNF+/− and wt. Compensatory glomerular hypertrophy in GDNF+/− was accompanied by higher numbers of endothelial and mesangial cells as well as PCNA-positive glomerular cells, whereas podocyte density was significantly reduced. Further electron microscopic analysis showed marked thickening of glomerular basement membrane. In conclusion, lower nephron number is associated with marked early glomerular structural changes, in particular lower capillary supply, reduced podocyte density, and thickened glomerular basement membrane, that may predispose to glomerular sclerosis.

Reduced capillary density in the myocardium of uremic rats—A stereological study. Using stereological techniques capillaries, interstitium and myocardial fibers were analyzed in perfusion-fixed hearts of subtotally nephrectomized male Sprague-Dawley rats with uremia of 14 months duration (or their sham-operated controls). Uremic rats had higher systolic blood pressure (140 ± 20.3mm Hg vs. 119 ± 6.61mm Hg) and left ventricular weight/body weight ratio (3.37 ± 0.09 mg/kg vs. 2.01 ± 0.12 mg/kg) than controls, and had slight anemia (Hct 35.0 ± 3.16% vs. 40.4 ± 3.3%). Length density (Lv) of capillaries, that is, capillary length per unit myocardial volume, was significantly (P < 0.001) decreased in uremia (2485 ± 264mm/mm3 vs. 3329 ± 194mm/mm3) versus controls. In parallel, surface density and volume density of the capillary lumina were also reduced (7.95 ± 1.69cm3/cm3 vs. 11.4 ± 1.8cm3/cm3) in the uremic rats. We conclude that in experimental uremia, cardiac hypertrophy is not accompanied by a commensurate increase in capillaries.

The effects of combined renovascular hypertension and diabetes mellitus on the rat heart were investigated in order to detect possible synergistic effects of the two conditions. Hypertensive diabetic and hypertensive non-diabetic animals were compared to diabetic and non-diabetic controls. Hypertension was established for 12 weeks by a surgical stenosis of the left renal artery; diabetes mellitus was maintained for 8 weeks by a single intraperitoneal injection of 60 mg/kg streptozotocin. Light microscopic stereology did not reveal significant divergences between diabetic hypertensives and non-diabetic hypertensives. Hypertension induced a focal perivascular and interstitial fibrosis with increased volume densities of non-vascular interstitium and fibrosis (P less than 0.001). Capillary density (QA) was decreased in transverse sections (P less than 0.01) and increased in longitudinal sections (P less than 0.01). This indicates a three-dimensional remodelling of the capillary bed with an increased number of obliquely running capillaries. At least the length density (LV) of capillaries (mm/mm3) tends to be normalized in long-term renovascular hypertension. At the ultrastructural level, a synergism of hypertension and diabetes mellitus was observed: the volume ratio of mitochondria to myofibrils was significantly decreased in hypertensive diabetics, but not in non-diabetic hypertensives or in diabetics. This may enhance the risk of cardiac deterioration. We conclude that the primary target of the synergistic damage in hypertensive diabetic heart muscle disease is the myocardial cell and not the cardiac interstitium.

Objectives. The aim of this study was to perform a multiple logistic regression analysis to identify independent structural determinants of impaired left ventricular function, Background. The association between contractile failure and structural alterations of the myocardium has been demonstrated in several studies, and multiple interactions between myocardial structure and cardiac performance are likely. Methods. Morphometric data assessed from 130 left ventricular biopsy specimens were analyzed. The endomyocardial specimens were obtained from 57 patients with normal coronary arteries (17 with normal left ventricular ejection fraction and 40 with impaired left ventricular function (dilated cardiomyopathy], 15 patients with hypertrophie cardromyopathy and 32 patients with aortic valve disease. Transmural biopsy specimens were assessed in 6 donor hearts before heart transplantation and in 20 patients with left anterior descending coronary artery disease whose specimens were obtained from the left ventricular anterior wall during aortocoronary bypass surgery. Global or regional left ventricular function was evaluated from left cineventriculograms. The volume fraction of cardiac fibrous tissue, intracellular volume fraction of myoftbrils, volume fraction of myofibrils related to myocardial tissue (including fibrosis) and myofiber diameters were determined from semithin sections of the biopsy specimens with the use of light microscopic morphometry. Results. Multiple logistic regression analysis revealed decreased volume fraction of myofibrils (p < 0.065) and iscreased fiber diameter (p < 0.002) as independent determinants of impaired left ventricular function. Conclusions. These data indicate that, independent of the underlying heart disease, both decreased concentration of contractile proteins and myocyte hypertrophy are independently associated with impaired left ventricular function.

We investigated the preventive effects of long-term treatment with the angiotensin converting enzyme inhibitor ramipril on myocardial left ventricular hypertrophy and capillary length density in spontaneously hypertensive rats. Rats were treated in utero and subsequently up to 20 weeks of age with a high dose (1 mg/kg per day) or with a low dose (0.01 mg/kg per day) of ramipril. Animals given a high dose of ramipril remained normotensive, whereas those given a low dose developed hypertension in parallel to vehicle-treated controls. At the end of the treatment period, converting enzyme activity in heart tissue was inhibited dose-dependently in the treated groups. Both groups revealed an increase in myocardial capillary length density together with increased myocardial glycogen and reduced citric acid concentrations. Left ventricular mass was reduced only in high dose- but not in low dose-treated animals. Our results demonstrate that early onset treatment with a converting enzyme inhibitor can induce myocardial capillary proliferation, even at doses too low to antagonize the development of hypertension or left ventricular hypertrophy. We hypothesize that potentiation of kinins is responsible for this effect, probably by augmenting myocardial blood flow, which is a well-known trigger mechanism of angiogenesis in the heart.

The effect of calcium channel blockers on the development of glomerulosclerosis and progression of renal failure in different models of renal injury is still controversial. We compared the effects of blood pressure lowering with high doses of nifedipine (27 mg/kg body weight/day) and with the sympatholytic agent moxonidine (8 mg/kg body weight/day) in 6-month-old male spontaneously hypertensive rats (SHRsp). As controls we studied untreated hypertensive SHRsp and normotensive Wisfar-Kyoto rats (WKY). After 3 months of treatment, left ventricular (LV) weight and systolic blood pressure (tail plethysmography) were lower in both treated groups (144 +/- 21.4 mm Hg and 144 +/- 13.5 mm Hg v 193 +/- 38.6 mm Hg in untreated SHRsp), but remained higher than in WKY (116 +/- 16.0 mm Hg). Stereological analysis of perfusion fixed kidneys showed an unchanged total volume of cortex and medulla, but a higher mean glomerular volume in nifedipine treated SHRsp. The glomerulosclerosis index was similarly reduced by both antihypertensive agents (92.8 +/- 68.1 in untreated SHRsp v 27.2 +/- 12.9 and 18.2 +/- 9.8 in the two treatment groups, respectively). This was accompanied by a similar reduction of total cortical arterial wall volume (from 36.3 +/- 16.5 mm3 to 18.9 +/- 2.53 and 15.3 +/- 2.53 mm3, respectively) and by reduction of tubular atrophy or interstitial fibrosis, respectively. In this model nifedipine lowered blood pressure and inhibited development of glomerulosclerosis to the same extent as a sympatholytic agent. This was accompanied by increased glomerular volume and filtration area in nifedipine treated animals.

Coxsackievirus B3-induced myocarditis in different immunocompetent mouse strains was used as a model to investigate interrelationships between virus replication and development of chronic enteroviral heart disease. Using in situ hybridization to detect enteroviral RNA, we show that heart muscle infection is not only detected in acute myocarditis but is also detected during the chronic phase of the disease. Coxsackievirus B3 could evade immunological surveillance in a host-dependent fashion, thus inducing a persistent infection of the myocardium in association with ongoing inflammation. Patterns of acute and persistent myocardial infection were quantitatively assessed in one representative mouse strain (A.CA/SnJ, H-2f) by applying computer-assisted digital image processing; these patterns were then related to the extent of myocardial tissue damage as well as to inflammation. We observed a strong correlation, both spatial and temporal, between viral replication and development of myocardial lesions, indicating that acute and chronic myocardial injuries are a consequence of multifocal organ infection. Analysis of strand-specific in situ hybridization revealed that viral replication in persistent infection is restricted at the level of RNA synthesis. The described procedure for quantitating organ infection provides a powerful tool for evaluating virus-host interactions and will be of particular interest to those studying human enterovirus-induced cardiomyopathies.

Effects of 1,25(OH)2D3 on compensatory renal growth in the growing rat. Renal compensatory growth after uninephrectomy (UNX) was examined in vitamin D replete male 100g Sprague-Dawley rats. Five days after UNX, the contralateral kidney wet weight increased by 25% with the kidney weight/body weight ratio reaching a plateau by day 7 after UNX. The early weight increase was primarily due to an increased cell number, as evaluated by a stereological technique in perfusion-fixed kidneys. Twenty pmol 1,25(OH)2D3 by daily s.c. injection increased time-averaged 1,25(OH)2D3 concentrations 3.3-fold and reduced the increment in the kidney weight of UNX pairfed rats compared to solvent UNX controls. The number of mitoses (whole kidney and different nephron segments) were significantly reduced by giving 1,25(OH)2D3 to UNX animals at different levels of food intake. The effect was also demonstrable in PTX animals on a constant infusion of exogenous PTH (100 ng/kg/hr 1,34 bPTH by osmotic minipump). The data suggest that changes of 1,25(OH)2D3 concentration within a physiologically relevant range modulate compensatory (and possibly basal) growth of the kidney.

Increasing evidence suggests an immunoregulatory function of the potent steroid hormone 1,25-dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ) which has been successfully applied for treatment of psoriasis. The skin is both a site of production and a target of 1,25(OH) 2 D 3 . In vitro, 1,25(OH) 2 D 3 inhibits proliferation and stimulates differentiation of keratinocytes. We investigated the in situ expression of vitamin D-receptors (VDR) in normal and psoriatic skin by immunochemical methods. The VDR were visualized using the monoclonal antibody (MoAb) 9A7g to the VDR and the labeled avidinbiotin technique. Immunoreactivity was consistently confined to nuclei in all skin biopsies. In normal skin specimens (n = 10) VDR antigens were expressed in keratinocytes of all epidermal layers (except those of the stratum corneum) and in cells of the epidermal appendages. Double labeling experiments with MoAb to cluster-defined antigens indicated that melanocytes and approximately 75% of Langerhans cells exhibit 1,25(OH) 2 D 3 receptors in normal skin biopsies (n = 5). Depending on their localization in skin compartments 42–62% of CD11b + positive macrophages and 45–75% of CD3 + T lymphocytes expressed VDR. Non-lesional psoriatic skin specimens (n = 8) revealed nearly identical staining patterns. Lesional psoriatic skin specimens (n = 8) exhibited a significant increase of VDR expression both in basal and suprabasal epidermal layers as measured by computer-assisted morphometry and showed a remarkable change of the immune cell pattern: the densitity and proportion of VDR positive T lymphocytes and macrophages were higher in the epidermal and the perivascular papillary loop compartment. These in vivo findings strongly support the hypothesis that 1,25(OH) 2 D 3 modulates immune response and cell proliferation/differentiation in human skin.

The prevention of the pulmonary toxicity of bleomycin (BLM) has been investigated in experimental models where pulmonary damage was induced with one intra-tracheal dose of BLM. The present investigation was carried out as a pre-clinical study in which BLM was administered systemically. The non-steroid anti-inflammatory drug indomethacin (INDO) was chosen as a possible candidate for pulmonary protection. Twenty female Wistar rats were treated daily with 4 mg/kg (7.3 units) BLM intra-peritoneally for 50 days and 20 rats with BLM and with 1 mg/kg INDO subcutaneously for 62 days. There were 20 animals as controls. Histological examination revealed fibrosing alveolitis in the BLM-treated group which was markedly suppressed in the combination group. Quantitative morphological (stereological) parameters demonstrate that BLM induced alveolar wall thickening (+45%), pulmonary fibrosis (+110%), and an increase of alveolar wall nuclei and of intra-alveolar macrophages (volume densities +43% and +133%, P less than 0.001). In contrast, after combination with INDO significant differences to the control group could not be detected except for a slight increase of intra-alveolar macrophages (+62%). Thus, INDO is a highly efficient agent in the prevention of BLM-induced pulmonary damage.

Combination of the two drugs bleomycin (BLM) and peplomycin (PEP) may enhance their antineoplastic effects; however, it is not known as to whether this enhancement is accompanied by a concomitant increase in toxicity, especially toxic lung damage. A histologic and stereologic investigation was carried out to compare the pulmonary toxicity of BLM, PEP, and a combination of the two drugs in animals. A total of 180 female Wistar rats were randomly assigned to 4 groups: 45 animals were treated with daily i.p. injections of 4 mg/kg BLM, 45 rats received 2.5 mg/kg i.p. PEP daily, 45 animals were given i.p. injections of a combination of 2.5 mg/kg BLM and 1 mg/kg PEP, and 45 rats received 1 ml 0.9% NaCl solution. Histological examination of the lungs demonstrated varying degrees of exudative and fibrosing alveolitis in animals treated with BLM, PEP, and BLM-PEP. Stereological analysis revealed a significant thickening of the alveolar wall after 20-60 days and a significant decrease in the surface density of alveolar walls after 40-60 days in all treated groups. Both histological examination and stereological parameters indicated more pronounced inflammatory changes in the alveolar walls and a prior loss of alveolar surface after 20 and 30 days in animals receiving PEP and PEP-BLM as compared with those undergoing BLM treatment. After 40-60 days, during which time irreversible fibrotic changes prevailed, significant stereological differences between the three treated groups could not be detected. Thus, our experimental observations did not show any potentiation of the toxic pulmonary effect of BLM and PEP following their combined administration.

Stereological investigations on myocardial capillaries provided evidence that the common estimator of capillarity, the capillary density (i.e., number of capillary profiles per unit transverse sectional area), underestimates the true capillary supply since the capillary axes are not oriented perfectly in parallel to the myofiber axes. Recently, we studied the "true" capillarity, i.e., the length density of capillaries (LV = capillary length per capillary volume), in some experimental models of cardiac hypertrophy which have been published elsewhere. It has been shown that LV decreases in renovascular hypertension, but is maintained in physical exercise and after chronic thyroxin application. However, the growth pattern of capillaries in hypertrophic hearts has not yet been analyzed. In the present paper it is demonstrated that important information on the capillary network can be derived from the two-dimensional capillary-to-fiber ratios (2D CFR: capillary profiles per myofiber profiles in transverse sections) and from the three-dimensional capillary-to-fiber ratios (3D CFR: capillary length per unit myofiber length). Increase in both suggests neoformation of additional capillary branches in parallel connection. Retrospective analysis of the quantitative data indicates that in hypertrophy induced by physical exercise or by chronic thyroxin application capillary neoformation in parallel connection counterbalances increase of oxygen diffusion distance due to myofiber enlargement. In renovascular hypertension, capillary neoformation in parallel connection does not occur. Studies on normal growth indicated both a slight decrease of LV of capillaries, as well as a continuous neoformation of additional capillary branches.

Myocardial infarctions were induced in rats by ligation of the left anterior descending (LAD) coronary artery. After 4 weeks, parameters of left (LV) and right ventricular (RV) function and of peripheral circulation were measured in the intact, anesthetized animals. The morphology of the heart chambers was examined at the macroscopic and cell size level. In animals with slight reduction in LV function, LVEDP was elevated from 3.4 ± 0.8 to 8.8 ± 1.5 mmHg, LV stroke work was reduced by 14%, and d P d t max of both ventricles was depressed by 10% compared with sham-operated controls. Myocytes isolated from the LV and RV were elongated to some extent and had a greater cell volume, but there was no change in heart weight. These rats had infarctions that were small or medium in size. In rats with severe depression in left heart function, cardiac output, LVSP, LV stroke work, mean arterial pressure, and the LV weight/body weight ratio were markedly lower than in sham-operated controls. LVEDP was elevated up to 32 ± 2 mmHg. These rats had large infarctions. RVSP, RV weight/body weight ratio, and the volume of myocytes isolated from the RV were doubled. RV stroke work was increased by 58%. Myocytes from the LV, RV and from the septum were elongated to about the same extent. The septum had developed a 23% hypertrophy. Histological examination of the lungs revealed marked thickening of the tunica medica of small pulmonary arteries with narrowing of the lumen. These changes are considered to represent the morphological basis for the increased pulmonary vascular resistance that was associated with RV pressure overload and hypertrophy.

In the past, cardiac changes in renal failure have commonly been ascribed to hypertension and poorly specified toxic effects ('uraemic cardiomyopathy'). Our recent experimental and clinical studies suggest (a) that cardiac hypertrophy can be dissociated from hypertension and that blood pressures may have only a permissive role, (b) that experimental uraemia is associated with specific activation of pericytes and intermyocardiocytic fibrosis. Cardiac hypertrophy not correlated with elevated blood pressure, and intermyocardiocytic fibrosis not observed in similarly hypertensive non-uraemic patients, have recently been documented in dialysis patients. The implications of these findings may be (a) electrical instability and predisposition to a sudden cardiac death and (b) diastolic cardiac malfunction with impaired LV filling and predisposition to dialysis hypotension. Some evidence for the latter possibility is provided.