[Molecular mechanisms and consequences of cardiac viral infections]

Molecular biological methods have confirmed the pathogenetic role of enteroviruses, primarily coxsackieviruses of group B (CVB), in the induction and maintenance of inflammatory cardiomyopathy. More recently, adenoviruses, various herpes viruses, and increasingly parvovirus B19 (B19) have been identified as potential cardiotropic agents. While cardiac myocytes are target cells for enterovirus and adenovirus infections with virus-induced cytolysis, B19-associated inflammatory cardiomyopathy is characterized by infection of intracardiac endothelial cells of small arterioles and veins, which may be associated with endothelial dysfunction, impairment of myocardial microcirculation, penetration of inflammatory cells, and secondary myocyte necrosis. Recent observations showed that B19 is involved in intracellular calcium regulation by the viral phospholipase. B19-induced caspase activation can lead to proinflammatory/proapoptotic processes through dysregulation of STAT signaling. These cellular interactions may contribute to mechanisms by which B19 establishes persistent infection in endothelial cells and play a critical role in viral pathogenesis of inflammatory cardiomyopathy.

[Detection of high-risk human papillomavirus (HPV) E6 and E7 oncogene transcripts increases the specificity of the detection of a cervical intraepithelial neoplasia (CIN)]

AIMS

The oncogenic potential of the high-risk human papillomavirus (HR-HPV) genotypes depends on the expression of the viral oncogenes E6 and E7. Thus, the detection of these transcripts could serve as a factor in the evaluation of a woman's risk of development of cervical intraepithelial neoplasia (CIN).

METHODS

A nested RT-PCR assay for the detection of E6/E7 oncogene transcripts of all known HR-HPV genotypes was established. Cervical scrapes of 779 HR-HPV-DNA-positive women exhibiting all grades of CIN were examined.

RESULTS

Spliced E6/E7 oncogene transcripts of all the HR-HPVs were detected in numerous samples. In 459 cases with agreement between the cytologic and histologic findings, the prevalence increased with lesion severity: CIN 0, 18%; CIN I, 58%; CIN II, 77%; CIN III, 84%. While sensitivity and negative predictive value of HR-HPV DNA-positivity for the detection of a CIN lesion were significantly (p < 0.0001) higher than those of E6/E7 mRNA positivity (90.3% vs. 65.5% and 93% vs. 83.1%), the opposite was true for the specificity and positive predictive value (72.8 % vs. 95.2%) and 65.1% vs. 88.5%, p < 0.0001). Preliminary follow-up data in 120 initially HPV-16 DNA-positive women revealed the development, persistence or progression of a CIN lesion in 33% (8/24) of HR-HPV DNA-positive and E6/E7 mRNA-negative women, compared to 93% (66/71, p < 0.0001) in women in whom transcriptional activity of the E6/E7 oncogenes was detectable.

CONCLUSIONS

Besides the identification of HPV DNA, the detection of HR-HPV E6/E7 oncogene transcripts may serve as a valuable tool in increasing the specificity of HPV testing.

Sudden cardiac death in myotonic dystrophy type 2

Medical records and follow-up data were reviewed in 297 genetically proven myotonic dystrophy type 2 (DM2) patients. Patients were selected by the criteria of cardiac sudden death before age 45. Sudden death occurred in four patients, three of whom were cardiological asymptomatic, and one with a history of heart failure. Cardiac histopathology showed dilated cardiomyopathy in all, and conduction system fibrosis in two patients. Pathogenetic CCUG ribonuclear inclusions were demonstrable in cardiomyocytes.

Detection and typing of human papillomavirus by e6 nested multiplex PCR

A nested multiplex PCR (NMPCR) assay that combines degenerate E6/E7 consensus primers and type-specific primers was evaluated for the detection and typing of human papillomavirus (HPV) genotypes 6/11, 16, 18, 31, 33, 35, 39, 42, 43, 44, 45, 51, 52, 56, 58, 59, 66, and 68 using HPV DNA-containing plasmids and cervical scrapes (n = 1,525). The performance of the NMPCR assay relative to that of conventional PCR with MY09-MY11 and GP5+-GP6+ primers, and nested PCR with these two primer sets (MY/GP) was evaluated in 495 cervical scrapes with corresponding histologic and cytologic findings. HPV prevalence rates determined with the NMPCR assay were 34.7% (102 of 294) in the absence of cervical intraepithelial neoplasia (CIN 0), 94.2% (113 of 120) in the presence of mild or moderate dysplasia (CIN I/II), and 97.8% (44 of 45) in the presence of severe dysplasia (CIN III). The combination of all four HPV detection methods applied in the study was taken as "gold standard": in all three morphological subgroups the NMPCR assay had significantly (P < 0.0001) higher sensitivities than the MY09-MY11 and GP5+-GP6+ assays and sensitivities comparable or equal to those of the MY/GP assay. All 18 HPV genotypes investigated were detected among the clinical samples. The ratio of high- to low-risk HPV genotypes increased from 4:1 (80 of 103) in CIN 0 to 19:1 (149 of 157) in CIN I to III. Multiple infections were detected in 47.9% (124 of 259) of the patients. In conclusion, the novel NMPCR method is a sensitive and useful tool for HPV DNA detection, especially when exact HPV genotyping and the identification of multiple HPV infections are required.

Fibromuscular dysplasia of the renal artery responsible for renovascular hypertension: a histological presentation based on a series of 102 patients

Background: Fibromuscular dysplasia (FMD) is a rare non-atherosclerotic and non-inflammatory disease in the arterial system. The purpose of the study was a retrospective analysis of FMD in the renal artery. Patients and methods: A total number of 102 patients (mean age: 36.9 years) who suffered from renovascular hypertension underwent a surgical therapy. The operative specimens of the renal arteries were analysed with the lightmicroscop using histological and immunohistochemical methods. Results: 101 patients (99.02%) presented a medial FMD (extensive-medial subtype in 56 patients, 54.9%, subadventitial subtype in 29 patients, 28.4% and combined subtype in 16 patients, 15.7%). In 1 patient (0.98%) an adventitial FMD was found. We observed the following complications: true and dissecting aneurysms (75 patients, 74.5%), arterio-venous fistulae (2 patients, 1.96%) and chronic thrombosis (10 patients, 9.8%). Conclusions: With the progress in angioplasty, not all patients suffering from FMD undergo a primary surgical therapy and therefore this lesion is less seen in the daily work of the histopathologist.

Urinary bladder biopsies in spinal cord injured patients

STUDY DESIGN

A series of 94 urinary bladder biopsies in spinal cord injured (SCI) patients were histopathologically and statistically analysed.

OBJECTIVES

The following hypotheses were examined: (1) The number of clinical bladder infections per year in each patient does not influence the histopathological type of inflammation of the urinary bladder; (2) The duration of the spinal cord lesion does not have a strong effect on the type of inflammation; (3) The different neurological levels (upper and lower motor neuron lesions) do not relate to a specific histopathology.

SETTINGS

All patients received their treatment at the Swiss Paraplegic Centre in Nottwil, near Lucerne (Switzerland).

METHODS

The samples were taken from the bladder fundus during endoscopic urologic operations. Histopathological standard procedures were carried out. Statistical analysis including Kruskal-Wallis and Chi-square tests were performed.

RESULTS

Histopathological analysis showed abnormal alterations of the urinary bladder mucosa in 86 SCI-patients: (91.5%). 63 cases (67.0%) showed a chronic type and 23 cases (24.5%) showed a subacute type of inflammation. A normal urinary bladder was found in eight cases (8.5%). The three hypotheses were statistically not rejected.

CONCLUSION

Results demonstrated no correlation between the number of bladder infections per year, the period since injury, the neurologic level of the spinal cord lesion and the histopathology of the urinary bladder mucosa.

Human papillomavirus type 16-associated primary squamous cell carcinoma of the rectum

Primary squamous cell carcinoma (SCC) of the colorectum is an extremely rare malignancy of unknown etiology and pathogenesis. We describe an 87-year-old man with primary SCC of the rectum. Routine histology demonstrated a squamous metaplasia-dysplasia sequence of the rectal mucosa with subsequent malignant transformation. Molecular biologic analysis using polymerase chain reaction (PCR) and in situ hybridization revealed the presence of human papillomavirus type 16 (HPV-16) DNA within metaplastic, dysplastic, and SCC lesions and in tumor-free rectal mucosa. Moreover, nested reverse-transcription PCR showed transcriptional activity of the viral E6/E7 oncogenes in tumor tissue and tumor-free rectal mucosa. By contrast, 4 typical adenocarcinomas of the rectum and their adjacent normal mucosa were found to be negative for HPV by nested PCR. In line with the well-established concept of HPV-associated anogenital carcinogenesis, our results strongly suggest an etiologic role of HPV-16 in the pathogenesis of the metaplasia-dysplasia-SCC sequence in the case described.

Lymph node micrometastases of cutaneous melanoma: increased sensitivity of molecular diagnosis in comparison to immunohistochemistry

The presence of regional lymph node metastases is one of the most significant prognostic factors for predicting survival in patients with clinical stage I or II cutaneous melanoma. For accurate staging of the primary tumor a sensitive technique is required to detect occult nodal micrometastases. This prospective diagnostic study was designed to evaluate the incidence of nodal micrometastases using nested reverse transcription-polymerase chain reaction (RT-PCR) for tyrosinase in comparison to immunohistochemical examination. Furthermore, the incidence of melanoma micrometastases detected by RT-PCR was analysed in correlation to major prognostic factors. A total of 466 regional lymph nodes from 79 patients with primary cutaneous melanoma (tumor thickness > 0.75 mm) were investigated. In 49 lymph nodes from 31 patients immunohistochemistry demonstrated melanoma metastases. Using tyrosinase RT-PCR, nodal micrometastases were detected in 136 lymph nodes from 52 patients including all lymph nodes positive by immunohistochemical examination. Out of the 417 lymph nodes negative by immunohistochemistry, 87 nodes (21%) were identified to express tyrosinase by the RT-PCR technique. Among the 48 patients negative by immunohistochemical assessment, 21 (44%) had nodal micrometastases (n = 40) using RT-PCR. All 68 lymph nodes from 46 non-melanoma patients serving as negative controls for tyrosinase RT-PCR were negative. The detection of melanocytic nodal micrometastases by tyrosinase RT-PCR is a highly specific method with a sensitivity significantly higher than that achieved by immunohistochemistry (p < 0.0001). Patients with nodal micrometastases identified exclusively by RT-PCR had significantly higher tumor thickness as compared to patients with negative results by RT-PCR (p < 0.01).

Extensive pectoral muscle necrosis after defibrillation: nonthermal skeletal muscle damage caused by electroporation

A 37-year-old Italian male developed a myocardial infarct with subsequent ventricular fibrillation. He was defibrillated seven times with up to 360 Joules. Thirteen days later the patient died of recurrent myocardial infarct due to thrombotic occlusion of the left circumflex coronary artery. At autopsy, necrosis of the right pectoralis muscle was observed. Electroporation is the pathogenetic mechanism of skeletal muscle damage due to multiple defibrillations with high energy levels.

Immunosuppressive therapy of chronic myocarditis in children: three cases and the design of a randomized prospective trial of therapy

Three infants, each with a clinical picture of dilated cardiomyopathy, underwent endomyocardial biopsy. Immunohistologic analysis revealed chronic myocarditis. In one infant, a postviral etiology of chronic myocarditis could be assessed on the basis of molecular techniques. Therapy with azathioprine and prednisone resulted in the normalization of echocardiographic findings. Based on these observations, a randomized, multicenter treatment study of chronic myocarditis in children (TCMC) has been initiated.

Detection of human papillomavirus type 16 E6/E7 oncogene transcripts in dysplastic and nondysplastic cervical scrapes by nested RT-PCR

Infections with high-risk human papillomaviruses (e.g., HPV-16) play an important role in the development of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (IC). Continued expression of the viral E6 and E7 genes is believed to be a key factor for oncogenic transformation of infected cells. Two spliced transcripts of the E6/E7 oncogenes, termed E6*I and E6*II, can be detected by reverse transcriptase polymerase chain reaction (RT-PCR). To increase the sensitivity of detecting E6/E7 transcripts in cervical scrapes we took advantage of a nested RT-PCR (nRT-PCR) protocol. In a series of 30 HPV-16-positive patients with histologic diagnoses ranging from nondysplastic epithelium to IC, the application of nRT-PCR significantly improved the detection of E6/E7 transcripts compared to conventional RT-PCR. The prevalence of E6/E7 spliced transcripts correlated with lesion severity and the nRT-PCR protocol allowed detection of these transcripts even in nondysplastic epithelium and CIN I lesions. Therefore, in epidemiologic follow-up studies, detection of E6/E7 transcripts by nRT-PCR should prove to be a useful diagnostic tool for risk evaluations regarding the development of CIN and its progression to cervical cancer, especially in high-risk HPV-type-infected patients with CIN 0 and CIN I.

Detection of human papillomavirus 16 transcriptional activity in cervical intraepithelial neoplasia grade III lesions and cervical carcinomas by nested reverse transcription-polymerase chain reaction and in situ hybridization

Continued expression of the oncogenes E6 and E7 of human papilloma virus "high risk" type 16 (HPV16) initiates neoplastic transformation and maintenance of the malignant phenotype in cervical carcinoma cells. The transcriptional activity of the HPV16 E6/E7 oncogenes was investigated in HPV16-containing cervical cell lines, cervical carcinomas, and cervical intraepithelial neoplasia grade III lesions using the techniques of reverse transcription-polymerase chain reaction (RT-PCR), Southern blotting, and in situ hybridization. To facilitate detection of the full-length HPV16 E6/E7 oncogene transcript and its characteristic splice products E6*I and E6*II in cervical tissues, a nested RT-PCR (nRT-PCR) assay was designed. Specific detection of HPV E6/E7 oncogene transcripts in clinical specimens was found to be improved by nRT-PCR, being as sensitive as the combination of conventional RT-PCR and subsequent Southern blot hybridization. Regarding the progression of premalignant lesions to cervical cancer, detection of the HPV transcriptional activity by nRT-PCR may provide additional information for risk evaluations. Moreover, improvements in the amplification of HPV oncogene transcripts may also be advantageous for monitoring the activity of HPV before and after transcript-targeted gene therapy of cervical cancer.

[Clostridium sordellii sepsis with intravascular haemolysis]

HISTORY AND CLINICAL FINDINGS

A 37-year-old chronic alcoholic had increasingly frequent haematemesis and recently had developed upper abdominal pain. His general condition had clearly deteriorated and he was finally admitted as an emergency. There were no previous illnesses other than alcoholism. He had a fever of 39.0 degrees C on admission, his sclerae were icteric and his abdomen was hard and resistant to palpation. He was slightly drowsy.

INVESTIGATIONS

Laboratory tests indicated haemolysis with a haemoglobin of 10 g/dl, lactate dehydrogenase concentration of 330 U/l, urobilinogenuria and a raised white blood cell count of 11,500/microliter. Sonography revealed liver cirrhosis and ascites.

TREATMENT AND COURSE

Because of the haematemesis a gastroscopy was performed, during which the patient went into acute shock from which he died. At autopsy the cause of the bleeding was found to be an ulcer at the oesophagocardiac junction. The gastrointestinal tract was filled with blood. He also had alcoholic liver cirrhosis with portal hypertension, as well as splenomegaly as sign of a septicaemia. Histologically masses of rod-shaped bacteria were found, especially in the heart, but also in liver, kidneys and peritoneum, which bacteriologically were identified as Clostridium sordellii.

CONCLUSION

In patients with impaired immunological resistance Clostridium sordellii may cause an acute and quickly fatal septicaemia with intravascular haemolysis.

[High malignant B-cell non-Hodgkin lymphoma of the heart: intravital diagnosis by transesophageal echocardiography controlled biopsy]

We report about a 66-year old patient with Non-Q-wave infarction in coronary artery two-vessel disease. During an echo- and transesophageal multiplane echocardiography preoperatively before a coronary artery bypass surgery a right atrium septal tumor of unknown form was discovered. The computerized axial tomography (CAT) and nuclear magnetic resonance (NMR) scans did not demonstrate extracardiac pathologic findings. A transesophageal echocardiography-guided biopsy of the right atrial septum over the vena femoralis and the right atrium enabled intra vitam a very early diagnosis of high malignant B-cell Non-Hodgkin-lymphoma without the need for thoracotomy. The diagnosis was confirmed histopathologically and immunohistochemically and early treatment with cytostatic therapy could begin. To our knowledge the transesophageal echocardiography-guided biopsy has never been described in the worldwide literature.

[Association of bone marrow mastocytosis with extremely immature extramedullary mast cell sarcoma]

The case of a 63-year-old man with a widespread retroperitoneal tumor and two tumor nodules in the left testis is described. Histopathological and cytopathological examination of tissue from the retroperitoneal tumor led to a diagnosis of lymphoreticular neoplasia. The patient died in acute cardiac failure, five weeks after initial presentation. Autopsy revealed another tumor nodule in the right atrium. Macroscopically, the bone marrow appeared normal. The tumor cells were reactive for CD45, vimentin and chloroacetate esterase, but were uncreative with a broad spectrum of antibodies against myelomonocytic and lymphocytic antigens and antibodies against tryptase and c-kit (CD117), characteristic markers for mast cells. However, the bone marrow exhibited the typical picture of mastocytosis. A diagnosis of bone marrow mastocytosis with an associated secondary extramedullary mast cell sarcoma was established. The cause of death was heart failure due to arrhythmia caused by an exophytic atrioseptal tumor nodule.

Pathogenesis of murine enterovirus myocarditis: virus dissemination and immune cell targets

In order to identify organ and cellular targets of persistent enterovirus infection in vivo, immunocompetent mice (SWR/J, H-2q) were inoculated intraperitoneally with coxsackievirus B3 (CVB3). By use of in situ hybridization for the detection of enteroviral RNA, we show that CVB3 is capable of inducing a multiorgan disease. During acute infection, viral RNA was visualized at high levels in the heart muscle, pancreas, spleen, and lymph nodes and at comparably low levels in the central nervous system, thymus, lung, and liver. At later stages of the disease, the presence of enteroviral RNA was found to be restricted to the myocardium, spleen, and lymph nodes. To characterize infected lymphoid cells during the course of the disease, enteroviral RNA and cell-specific surface antigens were visualized simultaneously in situ in spleen tissue sections. In acute infection, the majority of infected spleen cells, which are located primarily at the periphery of lymph follicles, were found to express the CD45R/B220+ phenotype of pre-B and B cells. Whereas viral RNA was also detected in certain CD4+ helper T cells and Mac-1+ macrophages, no enteroviral genomes were identified in CD8+ cytotoxic/suppressor T cells. Later in disease, the localization of enteroviral RNA revealed a persistent type of infection of B cells within the germinal centers of secondary follicles. In addition, detection of the replicative viral minus-strand RNA intermediate provided evidence for virus replication in lymphoid cells of the spleen during the course of the disease. These data indicate that immune cells are important targets of CVB3 infection, providing a noncardiac reservoir for viral RNA during acute and persistent myocardial enterovirus infection.

Ectopic prostatic tissue in the spleen

Ectopic prostatic tissue was found in the spleen in a 49-year-old white man who died of wide-spread malignant mesothelioma. The prostatic origin of the tissue was affirmed by positive immunohistochemical staining for prostatic specific antigen and prostatic acid phosphatase.

[Fatal outcome of a congenital aneurysm of the right sinus valsalvae ruptured into the right atrium]

In a 24-year-old female patient with sudden collapse an acute tricuspid insufficiency was presumed by echocardiography after the exclusion of pulmonary embolism. Aortography, however, revealed an aneurysm of the right sinus of Valsalva which had ruptured into the right atrium. Despite emergency surgery the patient died in protracted cardiac shock. Biopsy and autopsy showed pathognomonic findings of a congenital aneurysm (medial degeneration, reduction of elastic lamellae). Aneurysms of the sinuses of Valsalva are mainly caused by a rare connatal defect of the aortic wall; the right aortic sinus is involved most frequently, the sudden rupture uncovers the lesion. The characteristics of the reported case are compared with the literature under special consideration of etiology and pathologic anatomy of this unusual entity.

In vitro assessment of luminal dimensions of coronary arteries by intravascular ultrasound with and without application of echogenic contrast dye

To evaluate the impact and limitations of intracoronary ultrasound in the assessment of lumen, we examined 80 segments of 20 isolated coronary arteries with a mechanical ultrasound device (CVIS) comparing the results of ultrasound with the corresponding histological specimens. Ultrasound was performed with and without echogenic contrast dye (Laevovist, Schering AG, FRG). After application of contrast dye, correlation of luminal area between histology and ultrasound was improved from r = 0.85 to r = 0.89 (p = ns). Accuracy of lumen measurements was low in segments < 2.5 mm; only after application of contrast dye a relationship between ultrasound and histological measurements was found. In all cases in which a deviation of more than 20% between ultrasound and histology was observed, this deviation could be reduced by the application of contrast dye. There are considerable limitations in the accuracy of ultrasound measurements in the near field. Thus, further improvement of intracoronary ultrasound devices is mandatory. However, with the use of the currently available systems, additional application of echogenic contrast dye can improve accuracy of luminal measurements, especially in smaller size vessels.

Investigation of bone marrow lymphocyte subsets in normal, reactive, and neoplastic states using paraffin-embedded biopsy specimens

Bone marrow lymphocyte subsets in normal and reactive states and in neoplastic diseases involving the marrow were investigated with a select panel of monoclonal antibodies reactive on routinely processed, paraffin-embedded trephine biopsy material. In all cases, the antibodies beta F1 and UCHL1 (CD45RO) stained virtually equal numbers of T cells (reactive and neoplastic), whereas antibody OPD4 stained only about one half of this number of T cells. Antibody L26 (CD20) stained B cells (reactive and neoplastic) in all specimens. The T-cell to B-cell ratio in the normal marrow was between 4:1 and 5:1, and a significant increase in T-cell numbers was observed in reactive and myelodysplastic states. A significant increase in B-cell numbers, however, was seen only in marrow infiltrated by B-cell lymphoma. Bone marrow exhibiting infiltrates of B-cell lymphoma, acute leukemia, or myeloproliferative disorders showed normal or decreased numbers of T cells. These findings show that antibodies UCHL1, beta F1, and L26 can be used to determine the numbers of B and T lymphocytes in paraffin-embedded, formalin-fixed bone marrow specimens and thus may help to distinguish reactive T lymphocytosis from B-cell lymphoma.

Comparison of two mechanical ultrasound devices with and without echogenic contrast dye

To evaluate the impact and limitations of intracoronary ultrasound, 64 segments of 13 isolated coronary arteries were examined and 2 mechanical devices (device A, 30 MHz 5Fr [CVIS] and device B, 20 MHz 4.8Fr [Diasonics/Boston Scientific] were compared with the corresponding histologic specimens. Luminal dimensions were assessed with and without echogenic contrast dye (Laevovist, Schering AG, Germany). After application of contrast dye, correlation of luminal area between histology and ultrasound was improved from r = 0.62 to r = 0.77 (device B; p < 0.05) and from r = 0.82 to r = 0.88 (device A; p = NS). Low accuracy of lumen measurements in segments < 2.5 mm could be improved by application of contrast dye. The number of quadrants in which wall thickness measurements were impossible was significantly higher for device B (n = 56; 22%) than for device A (n = 28; 11%); p < 0.01. This may be due to the different ringdown diameters of both systems (B, 2.6 mm; A, 2.0 mm; p < 0.0001). In assessing wall thickness only in segments of > 2.5 mm, a reliable correlation between ultrasound and histology was found (A, r = 0.80; B, r = 0.60). Sensitivity of plaque (n = 51) detection was lower for device B (63%) than for device A (82%, p < 0.05), and measurements correlated with histology only for device A. There are considerable differences in the accuracy of ultrasound measurements between mechanical systems. Nevertheless, additional application of contrast dye can improve accuracy of luminal measurements, especially in smaller vessels.

Molecular pathogenesis of enterovirus-induced myocarditis: virus persistence and chronic inflammation

In situ hybridization studies have proved that myocardial enterovirus infections are detectable in all stages of acute and chronic enterovirus-induced myocarditis as well as in some patients with end-stage dilated cardiomyopathy, suggesting the possibility of myocardial enterovirus persistence. Possible enterovirus persistence in the human heart is supported by the discovery of enterovirus persistence in different murine models of chronic myocarditis, demonstrating that coxsackievirus B3, typically a cytolytic enterovirus, is capable of evading immunological surveillance in a host-dependent fashion. Progress is currently being made in unraveling the molecular mechanisms of enterovirus persistence, the diversity of host and virus genetics and their impact on the nature and severity of the disease. Apart from providing an etiologic diagnosis, there are therapeutic implications from the in situ demonstration of myocardial enterovirus infection. Evaluation of specific antiviral agents, for example interferons, may lead to the development of new therapeutic strategies capable of providing protection against myocardial enterovirus infection.

Demonstration of Epstein-Barr viral DNA in paraffin-embedded specimens of lymphoproliferative syndrome. Evidence for a productive infection comparable to lymphoblastoid cell lines

B-cell lymphoproliferative syndromes (LPS) occurring in immunodeficient subjects are frequently associated with EBV infections. Histology as well as EBV-related serology are not diagnostic, but demonstration of EBV DNA in LPS suspected lesions might be useful for diagnosis. We studied four autopsied cases of LPS that developed in the setting of bone marrow transplantation, with proliferations ranging from poly- to monoclonal. Our protocol of DNA extraction allowed detection of EBV DNA in formalin-fixed, paraffin-embedded tissue specimens of all four cases. In dot blot hybridization the sensitivity in these specimens was 10% as compared to fresh frozen material, but still sufficient for a biotinylated probe. Southern blotting with the former DNA was not successful due to extensive degradation. In situ hybridization resulted in positive signals in all cases, using either 35S or 3H labeled probes. The labeling pattern suggested virus replication in B cells of LPS. By this, LPS resembles productively infected lymphoblastoid cell lines rather than latently EBV-infected Burkitt's lymphoma (BL). These findings strengthen the concept of LPS as a distinct clinicopathologic entity, differing from monoclonal, latently EBV-infected BL, as well as from polyclonal infectious mononucleosis, and the more common EBV-negative Non-Hodgkin lymphomas of the immunocompetent host.

The involvement of oxygen radicals in acute pancreatitis

The purpose of this study was to assess the involvement of oxygen radicals in acute edematous and hemorrhagic pancreatitis. Acute pancreatitis was induced in rats by the CCK-analogue cerulein (5 micrograms/kg/h) and by retrograde injection of 5% sodium taurocholate for 30 min, 3.5 h, and 12 h. At the end of the infusion and observation time, serum enzymes, conjugated dienes, and malondialdehyde in the tissue were measured. Moreover, the tissue samples underwent light microscopical examination. In cerulein pancreatitis, an interstitial edema and intravascular margination of granulocytes in the pancreatic gland were observed after 3.5 h. After 12 h, the histological evaluation revealed a pronounced zymogen degranulation, extensive tissue necrosis and migration of granulocytes into the tissue. Parallelly, amylase and lipase increased by 15 and 35 times, respectively. In contrast, conjugated dienes and malondialdehyde increased in cerulein pancreatitis and reached their highest level after 3.5 h and decreased to normal levels after 12 h. The development of the histological damages and serum enzyme levels with sodium taurocholate pancreatitis was similar as compared to the cerulein pancreatitis, however, the development was faster and more traumatic. Already after 3.5 h an extensive zymogen degranulation and cell necrosis was observed. Concomitantly, the amylase and lipase levels increased by 90 and 30 times, respectively. Treatment with superoxide dismutase (100,000 U/kg/h) and catalase (400,000 U/kg/h) prevented lipid peroxidation and reduced zymogen degranulation and tissue necrosis. Tissue edema and inflammatory response were not affected in both models of acute pancreatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Oxygen free radicals in acute pancreatitis of the rat

This study aimed to assess the role of oxygen free radicals in acute pancreatitis. Acute pancreatitis was induced in rats by infusion of the CCK-analogue cerulein (5 micrograms/kg per hour) for 30 minutes, 3.5 hours, and 12 hours. After the infusion, serum enzymes and conjugated tissue dienes and malondialdehyde were measured and tissue samples were subjected to electron and light microscopy. Electron microscopy after 30 minutes showed moderate intracellular alterations. After 3.5 hours of cerulein infusion interstitial oedema and intravascular margination of granulocytes in the pancreatic gland were seen. After 12 hours histological evaluation showed pronounced zymogen degranulation, extensive tissue necrosis, and migration of granulocytes into the tissue. Amylase and lipase activities increased 15 and 35-fold respectively during this time. After 30 minutes of cerulein infusion conjugated dienes and malondialdehyde increased, they reached their peak after 3.5 hours and decreased to normal values after 12 hours. Treatment with superoxide dismutase (100,000 U/kg/hour) and catalase (400,000 U/kg/hour) either before or after the start of the cerulein infusion prevented lipid peroxidation and reduced zymogen degranulation and tissue necrosis. Tissue oedema and inflammatory response, however, were not affected in any of the treated rats. Oxygen free radicals are instrumental in the development of acute pancreatitis. Even after its onset, scavenger treatment reduced the tissue damage normally observed.

Glycolipid storage material in Fabry's disease: a study by electron microscopy, freeze-fracture, and digital image analysis

The glycolipid storage material in Fabry's disease was studied by electron microscopy of thin-sectioned (TS) and freeze-fractured (FF) specimens. In the kidney all deposits were found to be located in lysosomes, arranged as lamellar stacks. Deposits in the heart consisted of intracytoplasmic concentric whirls or folded lamellar structures. High resolution TS micrographs disclosed various defects in the lamellar structure. For stabilization, such defects require additional amphiphilic, surface-active molecules. These molecules could interact with other cellular constituents. The lamellar periodicity of the deposits in FF specimens was determined by reconstruction of the three-dimensional fracture face by digital image analysis. Homogeneous multilamellar deposits exhibited a periodicity of 14-15 nm, contrasting with the conventional estimates of 4-5 nm on TS micrographs. This difference is explained by better preservation of the physiologic hydrated state in FF specimens, with 1 vol of lipids binding 2 vol of water. Inhomogeneous structures with an even higher state of hydration included water lenses between the sheets. The strong hydration obviously contributes to the enlargement of the intracellular glycolipid deposits.

The role of lipoproteins in EBV early antigen induction in Raji cells

Synthesis of the Epstein-Barr virus (EBV) associated early antigen (EA) can be induced by a variety of agents in Raji cells, a latently EBV-infected Burkitt lymphoma line. We investigated the role of lipoproteins in this EA induction system. Cell growth was not affected by lipoprotein-deficiency, but EA induction by most combinations of the inducers TPA (tetradecanoyl-phorbol-acetate), IdU (iododeoxyuridine), n-BA (n-butyric acid), anti-IgM and EA inducing factor (EIF), was greatly reduced. Only the inducer combination TPA/n-BA was completely independent of the presence of lipoproteins, indicating a different induction pathway. Removing the lipid moieties of the culturing serum did not result in reduced EA induction. Thus, the lowered EA inducibility in lipoprotein-deficiency is due to the absence of the protein moiety (apolipoprotein). Addition of HDL or VLDL partially reconstituted the original EA inducibility, whereas LDL had no effect. Lipoproteins were particularly important during the first 4 hours of induction, the phase where inducers may act on cell membrane structures (e.g., receptors). But lipoproteins were also required throughout the incubation period, even in a late and inducer independent phase.

Involvement of oxygen radicals and phospholipase A2 in acute pancreatitis of the rat

The purpose of this study was to assess the involvement of oxygen radicals and phospholipase A2 in acute pancreatitis. Acute pancreatitis was induced in rats by the CCK-analogue cerulein (5 micrograms/kg.h) for 30 min, 3.5 h, and 12 h. At the end of the infusion, serum enzymes and the lipid peroxidation products conjugated dienes and malondialdehyde in the tissue were measured. Moreover, tissue samples underwent lightmicroscopical examination. After 3.5 h cerulein, an interstitial edema and a beginning accumulation of granulocytes in the pancreatic gland is observed. These changes are aggravating within 12 h, leading to tissue necrosis and migration of the granulocytes into the tissue. Concomitantly amylase and lipase increased by 15 and 35 times, respectively. Conjugated dienes and malondialdehyde increase already after 30 min cerulein and reach their highest levels after 3.5 h cerulein. At the same time the tissue activity of phospholipase A2 is elevated three fold. Rats were treated with superoxide dismutase and catalase before cerulein infusion. Treatment significantly prevents tissue necrosis, granulocyte accumulation, and edema formation. The enhanced activity of phospholipase A2, however, is unaffected by the treatment. Oxygen radicals seem to be instrumental in the development of the disease.

[Fine needle aspiration of the skin: diagnosis of malignant lymphoma and of cutaneous manifestations of myeloid hemoblastosis]

Fine-needle aspiration cytology of the cutis was carried out in 103 patients suffering from malignant lymphomas and myelogenous leukemias. All biopsies were performed using a novel aspiration device. Only in 7.8% of cases was it not possible to establish a cytological diagnosis because the biopsy specimens obtained were inadequate. The sensitivity of the method was 96.8%. There was a close correlation between the cytological and the final diagnosis (contingency coefficient C = 0.96). The method was equally efficient for primary evaluation as it was for the follow-up of patients with hematological neoplasms.

Morphological changes and membrane potential of human granulocytes under influence of chemotactic peptide and/or echo-virus, type 9

The membrane potential, Em, of human granulocytes (PMNs), was recorded using glass microelectrodes. The membrane potential Em exhibited potential fluctuations accompanied by characteristic changes of cell shape. The periodic potential fluctuations (7-s, 70-s, and 260-s periodicities) ascertained by the autocorrelation technique, suggested the existence of an internal clock. The chemoattractant f-Met-Leu-Phe (FMLP) had no influence on the periodicities, whereas the amplitudes of the fluctuations were increased by it. Treatment of PMNs with Echo 9 virus also resulted in hyperpolarization. The 70-s periodicity disappeared under virus treatment indicating a virus-induced change of the internal program and loss of chemotactic activity.

Experimental reovirus myocarditis in newborn mice. Electron microscopic observations

Reovirus is a double-stranded RNA-virus which induces myocarditis in newborn mice. Due to the large diameter of the viral particles (70-75 nm) it can be detected by electron microscopy. Subcutaneous inoculation of 0.05 ml reovirus type 3 (TCID50-titer: 10(8.5)/ml) into newborn NMRI-mice (12-18 h after birth) caused a grey-yellow mottling on the ventricular surface first seen on the 5th day after birth. At the same time muscle fiber necrosis was observed which increased with time. Electron microscopic investigations of the diseased heart muscle disclosed a marked interstitial oedema, swelling of the tubular system and sarcoplasmic reticulum, and degenerative changes in the mitochondria of individual myocardiocytes as early as the 2nd post-inoculation day. Simultaneously, an enlarged Golgi-apparatus and an increasing number of lysosomes, partially exhibiting acid phosphatase activity, was detected in the perinuclear region of ventricular myocardiocytes. On the 5th day after infection, viruses were detected either within single membrane vesicles, dispersed in cytoplasm or as aggregated clusters in the perinuclear region. These in vivo electron microscopic findings correspond with observations of virus propagation in cell-culture systems.