Pediatric and Adult Liver Disease in Alpha-1 Antitrypsin Deficiency

Alpha-1 antitrypsin deficiency (AATD) arises due to inherited variants in SERPINA1, the AAT gene that impairs the production or secretion of this hepatocellular protein and leads to a gain-of-function liver proteotoxicity. Homozygous Pi*Z pathogenic variant (Pi*ZZ genotype) is the leading cause of severe AATD. It manifests in 2 to 10% of carriers as neonatal cholestasis and 20 to 35% of adults as significant liver fibrosis. Both children and adults may develop an end-stage liver disease requiring liver transplantation. Heterozygous Pi*Z pathogenic variant (Pi*MZ genotype) constitutes an established disease modifier. Our review summarizes the natural history and management of subjects with both pediatric and adult AATD-associated liver disease. Current findings from a phase 2 clinical trial indicate that RNA silencing may constitute a viable therapeutic approach for adult AATD. In conclusion, AATD is an increasingly appreciated pediatric and adult liver disorder that is becoming an attractive target for modern pharmacologic strategies.

Prognostic relevance of topoisomerase II α and minichromosome maintenance protein 6 expression in colorectal cancer

BACKGROUND

Despite rising incidence rates of colorectal malignancies, only a few prognostic tools have been implemented in proven clinical routine. Cell division and proliferation play a significant role in malignancies. In terms of colorectal cancer, the impact of proliferation associated proteins is controversially debated. The aim of our study was to examine the expression of topoisomerase II α and minichromosome maintenance protein 6 and to correlate these findings with the clinical data.

METHODS

Tissue samples of 619 patients in total were stained using the antibodies Ki-S4 and Ki-MCM6 targeting topoisomerase II α as well as minichromosome maintenance protein 6. The median rate of proliferation was correlated with clinical and follow up data.

RESULTS

The expression rate of minichromosome maintenance protein 6 is significantly higher than the proportion of topoisomerase II α in tumour cells (p < 0.001). A high expression of both proteins coincides with a beneficial outcome for the patient, indicating a favourable prognostic marker (p < 0.001 and p = 0.008).

CONCLUSIONS

We have demonstrated that high expression rates of proliferative markers is linked to a beneficial patient outcome. According to the general opinion, a high expression rate correlates with a poor patient outcome. In this study, we were able to refute this assertion.

Value of micro-CT as an investigative tool for osteochondritis dissecans: A preliminary study with comparison to histology

Purpose: To evaluate micro computed tomography (micro-CT) for the assessment of osteochondritis dissecans in comparison with histology.

Material and Methods: Osteochondritis dissecans lesions of 3 patients were evaluated using micro-CT (0.125 mA, 40 keV, 60 μm slice thickness, 60 μm isotropic resolution, entire sample) and light microscopy (toluidine blue, 3–5 μm slice thickness). The methods were compared regarding preparation time, detectability of tissue types and morphologic features of bone and cartilage.

Results: Non-destructive micro-CT imaging of the entire sample was faster than histologic preparation of a single slice for light microscopy. Morphologic features of bone and cartilage could be imaged in a comparable way to histology. It was not possible to image cells or different tissue types of bone and cartilage with micro-CT.

Conclusion: Micro-CT is a fast, non-destructive tool that may be a supplement or, if detailed histologic information is not necessary, an alternative to light microscopy for the investigation of osteochondritis dissecans.

[Practical Use of the Levodopa Pump]

Patients with advanced Parkinson's disease and motor complications undergoing optimized oral therapy can significantly benefit from continuous intrajejunal levodopa/carbidopa infusion applied by means of a medication pump. However, this requires a correctly positioned PEG-J tube and finely adjusted pump settings. Although this method is a routine procedure in specialist centers, no standard procedure has been defined up to now. For this reason, an expert recommendation regarding the practical application has been developed in order to standardize the procedure and facilitate patient access to this treatment option.

Comparison and optimization of detection methods for noroviruses in frozen strawberries containing different amounts of RT-PCR inhibitors

Frozen berries have been repeatedly identified as vehicles for norovirus (NoV) transmission causing large gastroenteritis outbreaks. However, virus detection in berries is often hampered by the presence of RT-PCR-inhibiting substances. Here, several virus extraction methods for subsequent real-time RT-PCR-based NoV-RNA detection in strawberries were compared and optimized. NoV recovery rates (RRs) between 0.21 ± 0.13% and 10.29 ± 6.03% were found when five different artificially contaminated strawberry batches were analyzed by the ISO/TS15216-2 method indicating the presence of different amounts of RT-PCR inhibitors. A comparison of five different virus extraction methods using artificially contaminated strawberries containing high amounts of RT-PCR inhibitors revealed the best NoV RRs for the ISO/TS15216 method. Further improvement of NoV RRs from 2.83 ± 2.92% to 15.28 ± 9.73% was achieved by the additional use of Sephacryl(®)-based columns for RNA purification. Testing of 22 frozen strawberry samples from a batch involved in a gastroenteritis outbreak resulted in 5 vs. 13 NoV GI-positive and in 9 vs. 20 NoV GII-positive samples using the original ISO/TS15216 method vs. the extended protocol, respectively. It can be concluded that the inclusion of an additional RNA purification step can increase NoV detection by the ISO/TS15216-2 method in frozen berries containing high amounts of RT-PCR inhibitors.

Hepatitis E virus antibody prevalence in hunters from a district in Central Germany, 2013: a cross-sectional study providing evidence for the benefit of protective gloves during disembowelling of wild boars

Background

In Germany, 17 % of the general human population have antibodies to hepatitis E virus (HEV) (recomLine HEV-IgG/IgM immunoassay [Mikrogen GmbH]). Wild boars represent an animal reservoir for HEV genotype 3, which is the common genotype in Germany. We estimated the seroprevalence among hunters with contact to wild boars to identify factors that may be associated with past or present HEV infection.

Methods

In 2013, the local veterinarian authority in a district in Central Germany attended meetings of hunters who provided blood specimens and completed a questionnaire collecting information on age, sex, hunting-related activities and consumption of wild boar meat. Specimens of wild boars were taken during drive hunts in this district during the season 2012/2013. All specimens were tested for HEV RNA and anti-HEV IgM and IgG antibodies. Log-binomial regression was used to estimate prevalence ratios (PR) for the hunters.

Results

Of 126 hunters (median age 55; 94 % male) 21 % tested positive for anti-HEV IgG antibodies (95 % confidence interval [CI] 13–28 %) (recomWell HEV IgG assay [Mikrogen GmbH]). Anti-HEV prevalence was highest in the age group of the 70–79-year-olds (67 %; 95 % CI 39–95 %). Wild boars showed an average anti-HEV prevalence of 41 %. HEV RNA was detected in 4/22 (18 %) liver specimens and in 1/22 (4.5 %) muscle specimens. Most wild boars were tested positive for HEV RNA (3/10; 30 %) and HEV-specific antibodies (7/15; 47 %) in the southwestern part of the district. Hunters preferring this hunting ground had a lower anti-HEV prevalence when gloves were frequently used during disembowelling of wild boars compared to hunters using gloves never or infrequently (age-adjusted PR 0.12; 95 % CI 0.02–0.86).

Conclusions

Hunters may benefit from wearing gloves when in contact with blood or body fluids of HEV animal reservoirs. Anti-HEV prevalence among the hunters of this study did not significantly differ from that of the general population suggesting that other factors play a major role in the epidemiology of HEV in Germany.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1199-y) contains supplementary material, which is available to authorized users.

The NF-κB pathway is rarely spontaneously activated in mantle cell lymphoma (MCL) cell lines and patient's samples

In this study, we investigated the role of NF-κB (canonical and alternative pathways) in the survival or proliferation of mantle cell lymphoma (MCL) cell lines. P50/p65 complexes were detectable by EMSA assays in 4/5 cell lines. Stable expression of a dominant-negative form of IkBa had no effect on proliferation nor on apoptosis in EBV-negative cell lines. Three out of 4 of the cell lines tested exhibited Phospho-p65 (Ser(536)). The alternative NF-κB pathway was not activated in 4/5 cell lines tested. Patient samples were also studied by Western blot, EMSA and Immunohistochemistry (IHC). No p50/p65 complexes were detected in cells freshly collected from 7 patients, but 1/7 cells exhibited Phospho-p65 (Ser(536)). We investigated immunohistochemically, the expression of NF-κB in 86 patients enrolled in two multicentre prospective trials. Patients with MCL exhibiting negative or positive cytoplasmic expression of NF-κB had a median overall survival of 35.7months compared to 22.4months for patients with nuclear NF-κB expression (p=0.0193). All these data suggest that NF-κB does not play a key role in proliferation and apoptotic processes in MCL cell lines. In patient samples, the presence of p65 in the nucleus reflecting NF-κB activation is rare but associated with a poor outcome.

PCR inhibitors - occurrence, properties and removal

The polymerase chain reaction (PCR) is increasingly used as the standard method for detection and characterization of microorganisms and genetic markers in a variety of sample types. However, the method is prone to inhibiting substances, which may be present in the analysed sample and which may affect the sensitivity of the assay or even lead to false-negative results. The PCR inhibitors represent a diverse group of substances with different properties and mechanisms of action. Some of them are predominantly found in specific types of samples thus necessitating matrix-specific protocols for preparation of nucleic acids before PCR. A variety of protocols have been developed to remove the PCR inhibitors. This review focuses on the general properties of PCR inhibitors and their occurrence in specific matrices. Strategies for their removal from the sample and for quality control by assessing their influence on the individual PCR test are presented and discussed.

Determinants of paraoxonase 1 status: genes, drugs and nutrition

Paraoxonase 1 (PON1) is an enzyme which is mainly synthesized in the liver. PON1 circulates in the blood bound to HDL and delays or prevents the oxidation of LDL. Single nucleotide polymorphisms significantly determine PON1 status in humans. A high PON1 status may be associated with a reduced cardiovascular disease risk. By using in silico databases we suggest various transcription factors and micro RNA as putative regulators of PON1. Furthermore we predict functional partners of PON1 by using a text mining tool. Beside genetic and life style factors PON1 status may be determined by drugs (e.g., statins, fibrates) and dietary factors. Dietary modulators of PON1 status include fat and fatty acids, antioxidant vitamins (e.g. ascorbic acid, tocopherol), polyphenols and polyphenol-rich foods.

GPi-DBS may induce a hypokinetic gait disorder with freezing of gait in patients with dystonia

OBJECTIVES

Stimulation-induced hypokinetic gait disorders with freezing of gait (FOG) have been reported only recently as adverse effects of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with dystonia. The aim of this work was to determine the frequency and the nature of this GPi-DBS-induced phenomenon.

METHODS

We retrospectively screened our database of patients with dystonia who underwent DBS. Patients with focal, segmental, or generalized dystonia of primary or tardive origin and no gait disorder due to lower limb dystonia before DBS, bilateral pallidal stimulation, and a follow-up for more than 6 months were included. Reports of adverse events were analyzed, and gait abnormalities were scored by comparing preoperative and postoperative video recordings using Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) items 3.10 (gait) and 3.11 (FOG). To assess the role of GPi-DBS in gait abnormalities, DBS was paused for 24 hours. Gait and FOG were assessed 30 minutes, 2 hours, and 24 hours after restarting DBS. Finally, a standardized adjustment algorithm was performed trying to eliminate the gait disorder.

RESULTS

Of a collective of 71 patients with dystonia, 6 presented with a new gait disorder (8.5%; 2 men, 4 women, mean age 61.3 years [48-69 years], 2 craniocervical, 1 DYT-1 segmental, 1 truncal, 2 tardive dystonia). GPi-DBS improved Burke-Fahn-Marsden Dystonia Rating Scale motor score by 54% and disability score by 52%. MDS-UPDRS item 3.10 worsened from 0.5 (±0.8) to 2.0 (±0.9) and item 3.11 from 0 to 2.5 (±0.5). The gait disorder displayed shuffling steps and difficulties with gait initiation and turning. Increasing voltages improved dystonia but triggered FOG, sometimes worsening over a period of a few hours. It vanished within minutes after ceasing DBS. Electrode misplacement was ruled out. In all but one patient, no optimal configuration was found despite extensive testing of settings (monopolar, bipolar, pulse width 60-210 μs, frequency 60-180 Hz). Nevertheless, a compromise between optimal stimulation for dystonia and eliciting FOG was achieved in each case.

CONCLUSIONS

A hypokinetic gait disorder with FOG can be a complication of GPi-DBS.

Effect of quercetin on paraoxonase 1 activity--studies in cultured cells, mice and humans

There is increasing evidence that the HDL-associated enzyme paraoxonase 1 (PON1) may have a protective function in the atherosclerotic process. An enhancement of PON1 activity by dietary factors including flavonoids is therefore of interest. Quercetin, a flavonol frequently present in fruits and vegetables has been shown to induce PON1 in cultured liver cells, but the in vivo efficacy of a dietary quercetin supplementation has yet not been evaluated. To this end, we fed laboratory mice quercetin-enriched diets with quercetin concentrations ranging from 0.05 to 2 mg/g diet for 6 weeks and determined the expression of the hepatic PON1 gene and its protein levels. Since we could establish a moderate but significant induction of PON1 mRNA levels by dietary quercetin in mice, we aimed to proof whether healthy human volunteers, given graded supplementary quercetin (50, 100 or 150 mg/day) for two weeks, would respond with likewise enhanced plasma paraoxonase activities. However, PON1 activity towards phenylacetate and paraoxon was not changed following quercetin supplementation in humans. Differences between mice and humans regarding the PON1 inducing activity of quercetin may be related to differences in quercetin metabolism. In mice, unlike in humans, a large proportion of quercetin is methylated to isorhamnetin which exhibits, according to our reporter gene data in cultured liver cells, a potent PON1 inducing activity.

Neuraminidase inhibitor susceptibility of porcine H3N2 influenza A viruses isolated in Germany between 1982 and 1999

As an intermediate host of avian and human influenza A viruses (FLUAV) pigs may play a potential role in interspecies virus transmission and reassortment of viral genes including those conferring antiviral drug resistance. Porcine FLUAV isolated in Germany between 1989 and 2001 contains mutations in the M2 gene inducing amantadine resistance. No data exist on neuraminidase inhibitor (NAI) susceptibility of these porcine FLUAV. We studied the antiviral activity of NAI against seven selected H3N2 FLUAV isolated from pigs in Germany between 1982 and 1999. All isolates were susceptible towards oseltamivir and zanamivir in neuraminidase enzyme-inhibition assays. Both compounds inhibited virus spreading and reduced the virus yields and plaque size at low concentrations. Higher concentrations were necessary to reduce the plaque number. Two isolates that differed in glycosylation pattern of viral hemagglutinin (HA) showed markedly reduced drug susceptibility in cell culture-based assays.

Expert opinion based modelling of the risk of human infection with H5N1 through the consumption of poultry meat in Germany

According to current scientific opinion the risk of human infection with H5N1 via preparation and consumption of poultry meat is negligible.This opinion has not yet been challenged by a formal risk assessment, due to the lack of empirical data. We have developed a scenario pathway model as a conceptual framework for a formal assessment of the H5N1 risk to humans through consumption of poultry meat and parameterise the model using information derived from expert opinions. The aim of this study was to investigate whether the notion of an overall negligible risk via the oral infection route is consistent with ad hoc data and expert opinions on the relevant parameters of the model. The model is mainly based on expert opinion. A stochastic Monte-Carlo simulation was conducted which took into consideration (amongst others) the exposure and infection of chicken (broiler and layer), turkeys, ducks and geese, the probabilities of detection prior to slaughter, virus survival and contamination during slaughter, as well as during the cutting and preparation of meat in commercial plants and in private households, respectively. The empirical consumption pattern for poultry meat in Germany was taken into account in the simulation. The results show that the risk for the individual consumer is practically zero whereas up to 23 cases per year in Germany might occur if the upper (more pessimistic) ranges of the expert opinions apply. The finding of a low but non-negligible risk to the population is discussed in relation to the epidemiological information available from recent outbreaks in South East Asia.

Evidence of lymphangiogenesis in Warthin's tumor of the parotid gland

The details of the pathogenesis of cystadenolymphoma (Warthin's tumor) of the parotid gland are still unclear. Neovascularization is considered to be a pivotal factor for solid tumor progression and biological behavior of the tumor. Using double-labeling immunohistochemistry for LYVE-1 and CD34 (specific markers for lymphatic and vascular endothelial cells, respectively) this study analyzes lymphatic vessel density (LVD) and blood vessel density (BVD) in 10 Warthin's tumors and 10 pleomorphic adenomas of the parotid gland as well as in 5 normal parotid glands and 5 normal parotid lymph nodes. There was no significant difference in the intratumoral LVD and BVD among pleomorphic adenoma and normal parotid gland tissue. In contrast, the intratumoral LVD and BVD were significantly higher in Warthin's tumor than pleomorphic adenoma, normal parotid gland and parotid lymph node (P<0.0001 versus P<0.004). The increase in lymphatic vessels in Warthin's tumor suggests that epithelial tumor cells might promote lymphangiogenesis in this kind of lesions.

Redistribution of connexin43 in regional acute ischemic myocardium: influence of ischemic preconditioning

Connexins are known to play an essential role in the ischemic preconditioning (IP) of the heart; their functional role in this process, however, has not been clearly defined. For this reason, anesthetized rats were subjected to regional myocardial ischemia, with or without IP or reperfusion. In frozen sections of hearts, fluorescence immunohistochemical staining for connexin43 (Cx43) was performed. In contrast to undisturbed zones, tissue that had been subjected to ischemia revealed Cx43 immunostaining not only in the gap junctions but also in a conspicuous pattern in the free cellular membranes of the myocytes. In myocardium that was exposed to IP only, the ratio of immunofluorescence intensity in the free cellular membrane to that in the interior of the cell was 1.22 ± 0.04 (ratio in non-ischemia-exposed area = 1.04 ± 0.01). When 15 or 45 min of permanent ischemia followed IP, the effect became more evident (ratio = 1.31 ± 0.03 and 1.46 ± 0.03, respectively) and proved to be significantly greater than in the corresponding non-IP groups (ratio = 1.16 ± 0.03 and 1.30 ± 0.03, respectively, P < 0.01). Reperfusion led to an overall weakening of fluorescence intensities and a disappearance of the observed IP-specific differences. We conclude that IP initiates a redistribution of Cx43 from its natural position in the gap junctions toward the free plasma membrane, thereby improving the cell's chance of survival during the subsequent phase of prolonged ischemia by an unknown, supposedly gap junction-independent, mechanism.

Amantadine resistance among porcine H1N1, H1N2, and H3N2 influenza A viruses isolated in Germany between 1981 and 2001

This study was designed to gain insight into amantadine susceptibility of porcine influenza A viruses isolated in Germany between 1981 and 2001. The 12 studied H1N1, H1N2, and H3N2 porcine influenza virus strains were isolated in chicken eggs and passaged once in MDCK cells. Plaque reduction assays were applied to examine virus susceptibility to amantadine. Genotyping was used to confirm drug resistance. In the results of these antiviral studies, only 3 of the 12 isolates were shown to be amantadine-susceptible. All resistant strains contained the AA substitutions G16E, S31N, and R77Q in the membrane protein 2 (M2). Additionally, L27A was detected in two H1N1 strains. S31N and/or L27A are well-known amino acid substitutions in M2 that confer amantadine resistance. The role of the pig as an intermediate host of avian and human influenza A viruses, the possible involvement of genetic reassortment, and the high incidence of naturally amantadine-resistant porcine influenza A viruses suggest a real risk of emergence of amantadine resistant human viruses. Therefore, drug susceptibility monitoring appears to be warranted for effective application of those drugs.

[Childhood kidney tumors -- the relevance of imaging]

Kidney tumors represent 6.2% of malignant tumors in children. History, clinical course and radiological findings are necessary elements in the differential diagnosis of the different renal tumors. In the case of nephroblastoma, chemotherapy is based solely on the radiological diagnosis without prior histology. In therapy-optimizing studies of the Society of Pediatric Oncology and Hematology, preoperative chemotherapy is performed. Therapy monitoring is performed in the course of and after preoperative chemotherapy to verify tumor response. Radiological staging plays a significant role in deciding on further treatment and in operative planning. Three-dimensional visualization of the abdominal situs can assist preoperative planning. In summary, diagnostic imaging in renal tumors in children plays a role in differential diagnosis, staging, monitoring of therapy, and surgical planning.

TBE incidence versus virus prevalence and increased prevalence of the TBE virus in Ixodes ricinus removed from humans

Traditionally, the classification of risk areas of tick-borne encephalitis (TBE) is based on the recording of autochthonous cases of the disease. In Germany, an extension of these areas over the years and an increasing virus prevalence in ticks have been observed in recent years. Registration of foci with autochthonous TBE cases, recording of disease incidence and virus prevalence in ticks are all proven epidemiological methods to characterize TBE risk areas. These data are necessary for a scientifically proven recommendation of TBE vaccines, and they need to be updated regularly. These epidemiological methods have advantages and disadvantages with respect to the risk assessment of TBE areas. Despite the fact that these methods are suitable for risk assessment in practice, disease incidence (new cases per year/100,000 inhabitants) and virus prevalence in questing ticks did not correlate. Using nested RT-PCR we were able to demonstrate that the prevalence of TBE virus (TBEV) in ticks removed from humans was significantly higher than in unfed, free-living Ixodes ricinus of the same area. The 561 ticks collected from humans in doctors' surgeries in Bavaria in 2002 were examined by nRT-PCR. The estimated overall virus prevalence in tested ticks was 8.8% (95% CI: 6.45-11.57%). The removed ticks examined were classified according to the sites of exposure of the patients in the individual districts. Peak values were measured in the district of Regen with 20.6% and in the district of Freyung-Grafenau with 18.3%. In recent studies on unfed I. ricinus (nymphs, adults), the average TBEV prevalence in ticks in Bavarian risk areas was between 0.5% and 2%.

[Reference radiology in nephroblastoma: accuracy and relevance for preoperative chemotherapy]

PURPOSE

A reference radiologic diagnosis was carried out for the purpose of quality control and in order to achieve high diagnostic accuracy in the ongoing trial and study SIOP 2001/GPOH for renal tumors during childhood. The aim of the present study is to evaluate the value of diagnostic imaging and the benefit of reference evaluation at a pediatric radiology center.

MATERIALS AND METHODS

In 2004 the imaging studies of 97 patients suspected of having a renal tumor were presented at the beginning of therapy. Diagnostic imaging was compared to the primary imaging results and the histological findings and was analyzed in regard to the therapeutic consequence (primary chemotherapy without prior histology). 77 MRI, 35 CT and 67 ultrasound examinations of 47 girls and 50 boys (mean age 4 years; one day to 15.87 years old) were analyzed. In addition to the histological findings, the reference pathological results were submitted in 86 cases. Results from the primary imaging corresponding to the histology and results from the reference radiology corresponding to the histology were statistically compared in a binomial test.

RESULTS

In 76 of the reference-diagnosed Wilms' tumors, 67 were confirmed histologically. In 72 cases preoperative chemotherapy was initiated. In 5 cases neither a Wilms' tumor nor a nephroblastomatosis was found. 16 of 21 cases (76 %) with reference-diagnosed non-Wilms' tumors were selected correctly. The results of the primary imaging corresponded to the histology in 71 cases, and those of the reference radiology in 82 cases. The statistical evaluation showed that the results of the reference radiology were significantly better (p = 0.03971).

CONCLUSION

Reference radiological evaluation improved the diagnostic accuracy with therapeutic relevance. The differentiation of different renal tumors is not completely possible using imaging methods. The rate of patients with false preoperative chemotherapy for all renal neoplasms is currently 5.2 % and 1 % for benign renal tumors.

Lymphocyte subsets in irradiation-induced sialadenitis of the submandibular gland

AIMS

Irradiation-induced sialadenitis is a significant cause of morbidity in head and neck cancer patients receiving radiotherapy. Neither the exact aetiopathology of chronic irradiation-induced sialadenitis nor the mechanisms leading to atrophy of the glandular cells associated with an increase in extracellular matrix are understood. The aim of our study was to determine the phenotype of the inflammatory infiltrate and to study its distribution in the affected submandibular glands.

METHODS AND RESULTS

Paraffin-embedded submandibular glands from a homogeneous group of 19 patients with advanced oropharyngeal cancer who received conventional radiotherapy to the primary site and upper neck were analysed. In all patients the radiation dose and field were approximately equal. The submandibular glands were obtained during neck dissection. To characterize the lymphoid infiltrate, all tissue sections were immunostained for T cells (CD3, CD4, CD8), cytotoxic T cells (granzyme B), B cells (CD20), and macrophages (Ki-M1p). A histopathological classification into four grades was established based on the degree of glandular atrophy, fibrosis and lymphocytic infiltration. Phenotypic analysis of submandibular gland sections revealed that the great majority of lymphocytic infiltrates were cytotoxic T cells associated with acinar cell destruction.

CONCLUSIONS

The significantly elevated frequencies of cytotoxic cells in the submandibular glands of patients with irradiation-induced sialadenitis suggest that cell-mediated immune mechanisms may play a part in the pathogenesis of this disease.

Minichromosome maintenance protein 6, a proliferation marker superior to Ki-67 and independent predictor of survival in patients with mantle cell lymphoma

Minichromosome maintenance protein 6 (MCM6) is one of six proteins of the MCM family which are involved in the initiation of DNA replication and thus represent a marker of proliferating cells. Since the level of cell proliferation is the most valuable predictor of survival in mantle cell lymphoma (MCL), we investigated lymph node biopsy specimens from 70 patients immunohistochemically with a monoclonal antibody against MCM6. The percentage of MCM6 expressing lymphoma cells ranged from 12.0 to 95.6%, with a mean of 61.0%, and was significantly higher than the percentage of Ki-67-positive cells (P<0.0001). Surprisingly, the ratio of MCM6-positive cells to Ki-67-positive cells was higher than in normal stimulated peripheral blood mononuclear cells, indicating a cell early G1-phase arrest in MCL. A high MCM6 expression level of more than 75% positive cells was associated with a significantly shorter overall survival time (16 months) compared to MCL with a low MCM6 expression level of less than 25% (no median reached, P<0.0001). Multivariate analysis revealed MCM6 to be an independent predictor of survival that is superior to the international prognostic factor and the Ki-67 index. Therefore, aside from gene expression profiling, immunohistochemical detection of MCM6 seems to be the most promising marker for predicting the outcome in MCL.

[MRI-morphology and staging of congenital mesoblastic nephroma: evaluation of a collection with 20 patients]

PURPOSE

To differentiate classic and cellular type of congenital mesoblastic nephroma (CMN) in MRI and to evaluate MRI for staging according to the Societe Internationale de Oncologie Pediatrique (SIOP).

MATERIAL AND METHODS

MRI examinations of 20 children with CMN (age 1st to 16th months, classic type n = 11, cellular type n = 7, mixed type n = 2) were analyzed retrospectively. Cysts, necrosis, hemmorhage in the tumor, signal intensity, tumor structure, thrombosis and dilatation of renal vein, crossing of the body midline, peripheral contrast-enhancement, tumor volume and existence of a tumor pseudocapsule in contrast to the residual kidney were described. The radiologic stage was compared with the histopathologic stage (infiltration of perirenal fat and infiltration of the renal sinus).

RESULTS

Tumors of the classic type (mean volume 67.9 ml) had necrosis in 1 case, crossed the midline in 1 case, had no cysts or bleeding, and had a peripheral contrast-enhancement in 1 case, and were heterogeneous in 9 cases. The cellular type (mean volume 302.8 ml) had tumor necrosis in 6 cases, bleeding in 3 cases, cysts in 3 cases, crossed the midline in 4 cases, and peripheral contrast enhancement in 2 cases, and was predominantly heterogeneous. Mixed tumor types (7 ml and 202 ml) had tumor necrosis in 1 case and crossed the midline in 1 case, a peripheral contrast enhancement in 2 cases and a homogenous structure in 1 case. The signal intensity in T1 w and T2 w images was not specific. The renal vein was inconspicuous in all children. The evaluation of the infiltration in perirenal fatty tissue was true positive in 1 case, true negative in 10 cases, false negative in 4 cases and false positive in 5 cases. The infiltration of the renal hilus was true positive in 10 children, false positive in 8 cases and true negative in 2 cases.

CONCLUSION

A typical finding of CMN in MRI is a heterogeneous tumor without demarcation from the rest of the kidney parenchyma by a pseudocapsule. The cellular type of CMN tends to have a higher tumor volume and shows more necrosis, bleeding and cysts than the classic type in MRI. A peripheral contrast-enhancement in MRI is not characteristic for any type of CMN. Local tumor staging is not possible with MRI.