[Ultrastructure of pathologic deposits and cellular inclusions]. / Ultrastruktur pathologischer Ablagerungen und Zellinklusionen.

Intra- and extracellular depositions and inclusions occur in a wide range of diseases with exogenous (e.g. infectious, environmental and toxic) or endogenous (e.g. genetic, inflammatory, neoplastic and degenerative) aetiology. The noxious agent and the pathogenesis influence the organ of manifestation, the subcellular localisation and the ultrastructural appearance of the depositions. Whereas some of the inclusions like pathogens, foreign material (e.g. asbestos) or microvilli have an almost pathognomonic morphology, other inclusions are present in lower amounts also under normal conditions (e.g. lipid vacuoles and glycogen). Therefore, the interpretation of ultrastructural findings makes a correlation with the histological features and clinical constellation necessary. Auxiliary investigations by electron energy loss spectroscopy (EELS) or electron spectroscopic imaging (ESI) provide additional information about the chemical composition of the material and are therefore especially helpful for the identification of foreign substances. This review focuses on a selection of deposits and inclusions relevant to diagnostic pathology.

Assessment of Physiological Rat Kidney Ageing-Implications for the Evaluation of Allograft Quality Prior to Renal Transplantation.

Due to organ shortage and rising life expectancy the age of organ donors and recipients is increasing. Reliable biomarkers of organ quality that predict successful long-term transplantation outcomes are poorly defined. The aim of this study was the identification of age-related markers of kidney function that might accurately reflect donor organ quality. Histomorphometric, biochemical and molecular parameters were measured in young (3-month-old) and old (24-month-old) male Sprague Dawley rats. In addition to conventional methods, we used urine metabolomics by NMR spectroscopy and gene expression analysis by quantitative RT-PCR to identify markers of ageing relevant to allograft survival. Beside known markers of kidney ageing like albuminuria, changes in the concentration of urine metabolites such as trimethylamine-N-oxide, trigonelline, 2-oxoglutarate, citrate, hippurate, glutamine, acetoacetate, valine and 1-methyl-histidine were identified in association with ageing. In addition, expression of several genes of the toll-like receptor (TLR) pathway, known for their implication in inflammaging, were upregulated in the kidneys of old rats. This study led to the identification of age-related markers of biological allograft age potentially relevant for allograft survival in the future. Among those, urine metabolites and markers of immunity and inflammation, which are highly relevant to immunosuppression in transplant recipients, are promising and deserve further investigation in humans.

Skeletal muscle alterations in tachycardia-induced heart failure are linked to deficient natriuretic peptide signalling and are attenuated by RAS-/NEP-inhibition.

BACKGROUND: Heart failure induced cachexia is highly prevalent. Insights into disease progression are lacking. METHODS: Early state of left ventricular dysfunction (ELVD) and symptomatic systolic heart failure (HF) were both induced in rabbits by tachypacing. Tissue of limb muscle (LM) was subjected to histologic assessment. For unbiased characterisation of early and late myopathy, a proteomic approach followed by computational pathway-analyses was performed and combined with pathway-focused gene expression analyses. Specimen of thoracic diaphragm (TD) served as control for inactivity-induced skeletal muscle alterations. In a subsequent study, inhibition of the renin-angiotensin-system and neprilysin (RAS-/NEP) was compared to placebo. RESULTS: HF was accompanied by loss of protein content (8.7±0.4% vs. 7.0±0.5%, mean±SEM, control vs. HF, p<0.01) and a slow-to-fast fibre type switch, establishing hallmarks of cachexia. In ELVD, the enzymatic set-up of LM and TD shifted to a catabolic state. A disturbed malate-aspartate shuttle went well with increased enzymes of glycolysis, forming the enzymatic basis for enforced anoxic energy regeneration. The histological findings and the pathway analysis of metabolic results drew the picture of suppressed PGC-1α signalling, linked to the natriuretic peptide system. In HF, natriuretic peptide signalling was desensitised, as confirmed by an increase in the ratio of serum BNP to tissue cGMP (57.0±18.6pg/ml/nM/ml vs. 165.8±16.76pg/ml/nM/ml, p<0.05) and a reduced expression of natriuretic peptide receptor-A. In HF, combined RAS-/NEP-inhibition prevented from loss in protein content (8.7±0.3% vs. 6.0±0.6% vs. 8.3±0.9%, Baseline vs. HF-Placebo vs. HF-RAS/NEP, p<0.05 Baseline vs. HF-Placebo, p = 0.7 Baseline vs. HF-RAS/NEP). CONCLUSIONS: Tachypacing-induced heart failure entails a generalised myopathy, preceding systolic dysfunction. The characterisation of "pre-cachectic" state and its progression is feasible. Early enzymatic alterations of LM depict a catabolic state, rendering LM prone to futile substrate metabolism. A combined RAS-/NEP-inhibition ameliorates cardiac-induced myopathy independent of systolic function, which could be linked to stabilised natriuretic peptide/cGMP/PGC-1α signalling.

Combined Inhibition of the Renin-Angiotensin System and Neprilysin Positively Influences Complex Mitochondrial Adaptations in Progressive Experimental Heart Failure.

BACKGROUND: Inhibitors of the renin angiotensin system and neprilysin (RAS-/NEP-inhibitors) proved to be extraordinarily beneficial in systolic heart failure. Furthermore, compelling evidence exists that impaired mitochondrial pathways are causatively involved in progressive left ventricular (LV) dysfunction. Consequently, we aimed to assess whether RAS-/NEP-inhibition can attenuate mitochondrial adaptations in experimental heart failure (HF). METHODS AND RESULTS: By progressive right ventricular pacing, distinct HF stages were induced in 15 rabbits, and 6 animals served as controls (CTRL). Six animals with manifest HF (CHF) were treated with the RAS-/NEP-inhibitor omapatrilat. Echocardiographic studies and invasive blood pressure measurements were undertaken during HF progression. Mitochondria were isolated from LV tissue, respectively, and further worked up for proteomic analysis using the SWATH technique. Enzymatic activities of citrate synthase and the electron transfer chain (ETC) complexes I, II, and IV were assessed. Ultrastructural analyses were performed by transmission electron microscopy. During progression to overt HF, intricate expression changes were mainly detected for proteins belonging to the tricarboxylic acid cycle, glucose and fat metabolism, and the ETC complexes, even though ETC complex I, II, or IV enzymatic activities were not significantly influenced. Treatment with a RAS-/NEP-inhibitor then reversed some maladaptive metabolic adaptations, positively influenced the decline of citrate synthase activity, and altered the composition of each respiratory chain complex, even though this was again not accompanied by altered ETC complex enzymatic activities. Finally, ultrastructural evidence pointed to a reduction of autophagolytic and degenerative processes with omapatrilat-treatment. CONCLUSIONS: This study describes complex adaptations of the mitochondrial proteome in experimental tachycardia-induced heart failure and shows that a combined RAS-/NEP-inhibition can beneficially influence mitochondrial key pathways.

Nodular Cutaneous Amyloidosis at the Temple.

A 52-year-old woman presented with a large partially yellow and erythematous tumor on her right temple. She reported that it had grown over the last 4 years. Regional lymph nodes were impalpable. A punch biopsy showed eosinophilic material in the dermis and subcutis. Immunohistochemistry showed positive staining for kappa and lambda light chains. Electron microscopy showed the typical amyloid fibrils (7-10 nm in diameter). There was no evidence of systemic amyloidosis, paraproteinemia or underlying plasmacytoma. The tumor was completely removed via curettage. At follow-up, the patient presented in good health with no signs of relapse.

Nodular Cutaneous Amyloidosis Resembling a Giant Tumor.

A 79-year-old man presented with a large tumor on the left side of his head, which had grown over 5 years. Regional lymph nodes were impalpable and computed tomography revealed no signs of bone infiltration. Histology showed that the entire dermis was filled with amorphous eosinophilic material. Immunohistochemistry was negative for cytokeratin, but showed that the dermis and parts of the subcutis were filled with amyloid consisting of immunoglobulin light chains. There were no signs of paraproteinemia or underlying plasmocytoma. In electron microscopy, the typical amyloid fibrils were found. The tumor was completely removed via curettage. At 1-year follow-up, the patient was doing fine with no signs of relapse or systemic disease.

Erythrodermia Congenitalis Ichthyosiformis Bullosa of Brocq.

A 50-year-old man presented with congenital scaling and hyperkeratosis on his palms, the soles of his feet and the extensor areas of his joints. The flexural areas were unaffected. His maternal grandmother, questionably his maternal uncle, his mother, all three brothers, one of his two sisters as well as two nephews and three nieces have or had similar skin changes. A punch biopsy was taken from the left palm. Clinical and histological signs led to the diagnosis of erythrodermia congenitalis ichthyosiformis bullosa of Brocq. We confirmed this genetically and found a heterozygous duplication (c.1752dupT) in the keratin 1 gene (KRT-1). To our knowledge, this is the first case of this skin condition reported in the literature with a heterozygous duplication (c.1752dupT) in KRT-1.

Singlet oxygen generation in porphyrin-doped polymeric surface coating enables antimicrobial effects on Staphylococcus aureus.

Surfaces can be coated with photosensitizer molecules, which generate singlet oxygen ((1)O2) when the surface is exposed to light. (1)O2 may diffuse from the coating and has the potential to kill microorganisms present on the surface. In the present study a derivative of the meso-tetraphenylporphyrin (TPP) was immobilized onto polyurethane (PU) after being sprayed and polymerized as a thin layer onto poly-methylmethacrylate (PMMA). PU is gas permeable and thus a sufficient amount of oxygen reaches the photosensitizer in this coating. The surface generation of (1)O2 and its diffusion were investigated by detecting its luminescence at 1270 nm and a tri-iodide assay. Antimicrobial photodynamic surface effects were tested on Staphylococcus aureus. The spectrally resolved detection of (1)O2 luminescence yielded a clear peak at 1275 nm. The time-resolved luminescence showed multi-exponential decay, revealing rise and decay times in the range of 5-2 × 10(2)µs. The photodynamic inactivation of S. aureus was monitored at different photosensitizer concentrations and radiant exposures of light. A photodynamic killing of >99.9% (>3log10-steps) was achieved within an irradiation time of 30 min. The photodynamic killing on the bioactive surface confirmed the antimicrobial effect of (1)O2 that was generated in the PU-coating and reached the bacteria by diffusion.

Interatrial differences of basal molecular set-up and changes in tachycardia-induced heart failure-a proteomic profiling study.

AIMS: Left and right atria show compelling differences regarding organogenesis and specific clinical diseases. In congestive heart failure (CHF), remodelling of the atria occurs leading to increased arrhythmogenic susceptibility and deterioration of clinical symptoms. We aimed to assess the basal left and right atrial molecular set-up and different chamber-specific atrial changes in heart failure. METHODS AND RESULTS: We combined an animal model of rapid ventricular pacing induced heart failure in the rabbit and a gel-based proteomic screening of left and right atrial specimen. A gene ontology over-representation analysis was performed for biological function. Ultrastructural adaptations were evaluated using transmission electron microscopy. Comparing left and right atria of healthy control animals (CTRL), 39 proteins displayed significant expression differences involving various biological functions. Upon further statistical analyses, four pathways of energy metabolism were confirmed to be significantly over-represented beneath the other biological processes. Rapid ventricular pacing induced severe left ventricular systolic dysfunction, symptomatic heart failure and a macroscopic atrial remodelling. In CHF versus CTRL, metabolic and antioxidative enzymes were differentially expressed and showed chamber-specific bidirectional alterations. Transmission electron microscopy visualized a remarkable and again chamber-specific ultrastructural disturbance of mitochondrial morphology. CONCLUSIONS: Our data indicate a diverging basal left and right atrial molecular set-up in the adult healthy heart. In addition, metabolic and antioxidative enzymes are profoundly and chamber-specifically altered during atrial remodelling in progressive heart failure.

Luminescent dual sensors reveal extracellular pH-gradients and hypoxia on chronic wounds that disrupt epidermal repair.

Wound repair is a quiescent mechanism to restore barriers in multicellular organisms upon injury. In chronic wounds, however, this program prematurely stalls. It is known that patterns of extracellular signals within the wound fluid are crucial to healing. Extracellular pH (pHe) is precisely regulated and potentially important in signaling within wounds due to its diverse cellular effects. Additionally, sufficient oxygenation is a prerequisite for cell proliferation and protein synthesis during tissue repair. It was, however, impossible to study these parameters in vivo due to the lack of imaging tools. Here, we present luminescent biocompatible sensor foils for dual imaging of pHe and oxygenation in vivo. To visualize pHe and oxygen, we used time-domain dual lifetime referencing (tdDLR) and luminescence lifetime imaging (LLI), respectively. With these dual sensors, we discovered centripetally increasing pHe-gradients on human chronic wound surfaces. In a therapeutic approach, we identify pHe-gradients as pivotal governors of cell proliferation and migration, and show that these pHe-gradients disrupt epidermal barrier repair, thus wound closure. Parallel oxygen imaging also revealed marked hypoxia, albeit with no correlating oxygen partial pressure (pO2)-gradient. This highlights the distinct role of pHe-gradients in perturbed healing. We also found that pHe-gradients on chronic wounds of humans are predominantly generated via centrifugally increasing pHe-regulatory Na+/H+-exchanger-1 (NHE1)-expression. We show that the modification of pHe on chronic wound surfaces poses a promising strategy to improve healing. The study has broad implications for cell science where spatial pHe-variations play key roles, e.g. in tumor growth. Furthermore, the novel dual sensors presented herein can be used to visualize pHe and oxygenation in various biomedical fields.

Entrapment syndrome of multiple nerves in graft-versus-host disease.

INTRODUCTION: Peripheral nerve entrapment syndromes are associated with hereditary neuropathy with liability to pressure palsies and a variety of rheumatic and endocrinological diseases. METHODS: We report a patient with entrapment syndromes of multiple nerves associated with chronic graft-versus-host-disease (GVHD) after allogeneic hematopoietic stem cell transplantation. Nerve ultrasound, histology, and ultrastructural changes were assessed. RESULTS: The 51-year-old man had developed severe deep dermal sclerosis due to chronic GVHD with a progressive polyneuropathy and entrapment syndromes of multiple nerves. Pre-stenotic enlargement was shown by nerve ultrasound. Histology demonstrated fibrosis of the epineurium with scarce infiltration of macrophages. Electron microscopy demonstrated alterations of the myelin sheaths and marked depletion of normal-sized myelinated nerve fibers. CONCLUSIONS: In addition to polyneuropathy, chronic GVHD can be associated with peripheral nerve entrapment syndromes and should be added to the differential diagnosis of compressive neuropathies.

Proteomic profiling implies mitochondrial dysfunction in tachycardia-induced heart failure.

BACKGROUND/OBJECTIVES: Molecular mechanisms of congestive heart failure as reflected by alterations of protein expression patterns are still incompletely analyzed. We therefore investigated intraventricular (ie, left ventricular congestive heart failure [LV-CHF] vs. LV-control [CTRL], and right ventricular [RV]-CHF vs. RV-CTRL) and interventricular (ie, LV-CHF vs. RV-CHF, and LV-CTRL vs. RV-CTRL) protein expression differences in an animal model. METHODS: The model of rapid ventricular pacing in rabbits was combined with a proteomic approach using 2-dimensional gel electrophoresis. Identification of proteins was done by matrix-assisted laser desorption/ionization-tandem mass spectrometry (MALDI-MS/MS). RESULTS: Rapid ventricular pacing-induced heart failure was characterized by LV dilatation, dysfunction, and hypotension as well as by increased BNP gene expression. By comparing LV-CHF vs. LV-CTRL, proteins were found to be underexpressed at 3 crucial points of cellular energy metabolism. In RV-CHF vs. RV-CTRL, proteins belonging to respiratory chain complexes were underexpressed, but additionally a disturbance in the nitric oxide-generating enzymatic apparatus was seen. Regarding the interventricular analyses, a stronger expression of energetic pathways was accompanied by an underexpression of contractile and stress response proteins in failing left vs. right ventricles. Finally, significant protein expression differences were found in LV-CTRL vs. RV-CTRL reflecting a higher expression of contractile, stress response, and respiratory chain proteins in LV tissue. CONCLUSIONS: In tachycardia-induced heart failure, significant inter- and intraventricular protein expression patterns were found with a predominance of proteins, which are involved in cellular energy metabolism.

Histopathological patterns of nephrocalcinosis: a phosphate type can be distinguished from a calcium type.

BACKGROUND: The etiology of nephrocalcinosis is variable. In this study, we wanted to elucidate whether the histopathological appearance of calcium phosphate deposits provides information about possible etiology. METHODS: Autopsy cases from the years 1988 to 2007 and native kidney biopsies from a 50-year period (1959-2008) with nephrocalcinosis were identified. The biopsy cases were re-evaluated by light microscopy. The autopsy cases were analysed according to the underlying disease. The biopsy cases were grouped with respect to the likely etiology of nephrocalcinosis. Total number, density, localization, size and pattern of all calcification foci were documented and correlated with clinical and laboratory data. RESULTS: About 223 of 12,960 autopsy cases (1.7%) had nephrocalcinosis, 111 of which (49.8%) suffered from advanced malignant tumours. Nephrocalcinosis was the main diagnosis in 48 of 12,480 native kidney biopsies (0.4%). Clinicopathological correlation revealed a specific pattern of calcification associated with hyperphosphataemia and/or hyperphosphaturia: these cases showed predominant globular or shell-like calcifications (phosphate type). In contrast, the biopsies of the hypercalcaemic/hypercalciuric group had a different predominant pattern with clumpy or finely granular calcifications (calcium type). CONCLUSIONS: Our results indicate that hyperphosphaturia-associated cases of nephrocalcinosis can be distinguished from hypercalciuria-associated cases histopathologically.

Apoptosis as a mechanism for the elimination of cardiomyocytes after acute myocardial infarction.

Apoptosis is recognized as a mechanism of cell loss in the setting of acute myocardial infarction (AMI). Whether it contributes to myocyte elimination late after AMI has not yet been confirmed. We attempted to identify the features of apoptosis in myocytes that survived AMI. A search for ongoing apoptosis was performed in samples obtained from 38 human hearts: group I (n = 10), noncardiac death (control); and group II (n = 28), left ventricular aneurysm (in 20 patients, the samples were collected during aneurysmectomy and from 8 at autopsy). The morphometric evaluation included the degree of cellular hypertrophy, density of the capillary network, extent of myocytolysis, and features of apoptosis. Immunohistochemistry for caspase-3 and Bcl-2 was used as a prerequisite for transmission electron microscopy. Slides showing the strongest reaction for caspase-3 and negative for Bcl-2 were selected for transmission electron microscopy. CD-34 immunohistochemistry was used to quantify the capillary density. A significant reduction in capillary density was observed compared to the control group (1,085.6 + or - 205.0/mm(2) vs 2,968.7 + or - 457.3/mm(2); p <0.001). Myocytes that survived the acute phase of AMI were significantly hypertrophied (24.5 + or - 4.7 microm vs 14.5 + or - 1.6 microm; p <0.001) and showed a moderate to severe degree of myocytolysis. The average intensity score of the immunohistochemistry reactions for caspase-3 was 8.2 + or - 3.8. Using transmission electron microscopy, apoptotic bodies were found in caspase-3-positive samples. In conclusion, the expression of caspase-3 and the presence of apoptotic bodies confirmed apoptosis as a common pathway of cardiomyocyte death in the setting of a limited blood supply after AMI.

Dental resin materials in vivo - TEM results after one year: a pilot study.

Dental resins deteriorate clinically due to chewing forces, temperature changes, chemical agents or biological attack. Findings concerning these influences on the different components of a resin are limited. The aim of this study was to evaluate an alternative method for assessing the influence of the oral cavity on dental materials and their individual components as well as analyzing degradation effects over time. Seven dental composite and resin materials were inserted into the upper complete dentures of two subjects and evaluated after one year with a transmission electron microscope. The various resin components showed different degrees or deterioration. Composites with an urethandimethacrylate matrix were less vulnerable. A layer of salivary proteins (pellicle) was found on all materials but the polymethylmethacrylate reference. An accumulation of pellicle on filler particles and the crevice between filler and matrix was noted. We conclude that the tested method is effective for evaluating the interaction between the material's components and the biological environment. Further studies are needed to confirm these observations.

5-Fluorouracil-related enhancement of adenoviral infection is Coxsackievirus-adenovirus receptor independent and associated with morphological changes in lipid membranes.

AIM: To evaluate the mechanism underlying the effects of 5-Fluorouracil (5-FU) on adenoviral infection. METHODS: Low and high Coxsackievirus-Adenovirus Receptor (CAR) expressing human colon carcinoma cell lines were treated with 5-FU and two E1-deleted adenoviral constructs, one transferring GFP (Ad/CMV-GFP) the other bax (Ad/CEA-bax). The number of infected cells were monitored by GFP expression. To evaluate the effects of 5-FU in a receptor free system, Ad/GFP were encapsulated in liposomes and treated with 5-FU. Ad/GFP release was estimated with PCR and infection of 293 cells with the supernatant. Electron microscopy of the Ad5-GFP-liposome complex was made to investigate morphological changes of the liposomes after 5-FU. RESULTS: Infection rates of all cell lines increased from 50% to 98% with emerging 5-FU concentrations. The enhanced viral uptake was independent of the CAR expression. Additionally, 5-FU treated liposomes released 2-2.5 times more adenoviruses. Furthermore, 5-FU-treated liposomes appeared irregular and porous-like. CONCLUSION: Adenoviral uptake is enhanced in the presence of 5-FU irrespective of CAR and is associated with morphological changes in membranes making the combination of both a promising option in gene therapy.

Arthroscopic and histologic findings in Morquio's syndrome.

Mucopolysaccharidosis type IV A/B (Morquio's syndrome) is one of a heterogeneous group of lysosomal storage diseases characterized by accumulation of keratan sulfate in cells of connective tissue. From early childhood, the major orthopaedic manifestations are shortening of the trunk, spondylepiphyseal dysplasia, odontoid hypoplasia, upper cervical instability, lower-limb alignment problems, and degenerative joint disease. Most of the rare published case reports describe those characteristic clinical deformities of the skeleton. Our literature search showed that these striking arthroscopic findings have not been made public to date. We report a typical case of mucopolysaccharidosis type IV. We show and, in particular, correlate the arthroscopic with the histologic findings. In particular, the comparison between arthroscopy and light microscopy showed a remarkable extensive delamination of the chondral layer from subchondral bone of both knee joints. These findings should encourage further research, especially of the osteochondral borderline.

Role of apoptosis in myocardial stunning after open heart surgery.

BACKGROUND: Myocardial preservation during open heart surgery is a subject of intense investigation. A prerequisite for further improvement is a better understanding of the underlying pathophysiologic mechanisms responsible for postoperative myocardial stunning. In this report, we analyzed the role of apoptosis in myocardial stunning. METHODS: Myocardial samples were obtained from 11 patients undergoing elective coronary artery bypass grafting before (control) and after cardioplegic arrest and reperfusion. Specimens were examined for apoptosis by electron microscopy, in situ end-labeling of DNA fragments, and biochemically for mitochondrial cytochrome c release. RESULTS: Electron microscopy revealed condensation and margination of nuclear chromatin after surgery, as well as swelling and membrane rupture in mitochondria of single myocytes surrounded by healthy cells. TUNEL-positive cells were also found. Cytochrome c release, an initial step in apoptosis, revealed a 3.4 +/- 0.4-fold increase during surgery (p < 0.0001). Furthermore, cytochrome c release from otherwise intact mitochondria showed a negative correlation with left ventricular function and a positive correlation with the duration of cardioplegic arrest and reperfusion (p < 0.05). CONCLUSIONS: Our data demonstrate that programmed cell death is evident early after open heart surgery and correlates with declining cardiac contractility. We conclude that apoptosis may be an important mechanism in postoperative myocardial stunning.