Extracellular Citrate in Health and Disease.

Citrate is one of the major substrates for intracellular metabolism. The extracellular level of citrate is stable in blood but varies locally, with slightly increased levels in brain and high levels in prostate. Recent metabolomics research suggests that citrate level is a potential harbinger of different pathophysiological states; its decrease has been correlated with male infertility, brain diseases and metastatic cancer. In this review we discuss the role of citrate as an energy substrate for sperm. We also review the function of citrate released by astrocytes in the normal operation of neurons, and consequently we suggest a potential role of neuronal plasma membrane citrate transporters in mental disorders. Finally, we review recent relevant publications studying blood, urine and tissue citrate levels in cancer patients and hypothesize that extracellular citrate supports cancer cell metabolism critical for metastasis. Despite the importance of extracellular citrate in physiological and pathophysiological processes, surprisingly little is known about citrate synthesis in specialized cells, or about citrate transporters controlling citrate movement across various membranes. Determination of the molecular origin of citrate transporters in astrocytes, sperm and cancer cells could offer novel therapeutic targets and the possibility to pharmacologically regulate citrate release and uptake for preventing male infertility, treating mental diseases and targeting cancer.

[Conjunctival amyloidosis]. / Konjunktivale Amyloidose.

BACKGROUND: This article reports a case of primary localized conjunctival λ light-chain (AL) amyloidosis. METHODS: Case report. RESULTS: A 73-year-old woman presented with a 1-year history of a painless growth in the conjunctiva of the left eye. A yellow-salmon pink diffuse mass of tissue was identified in the inferomedial bulbar conjunctiva and inferior fornix. An incisional biopsy was performed. The histopathological and immunohistochemical examinations revealed interstitial and vascular amyloid deposits of λ light chains. The diagnosis was amyloidosis of the conjunctiva. The systemic evaluation revealed normal findings and systemic amyloidosis was excluded. Nevertheless, due to an unexplained cardiac insufficiency and after consultation with the treating hematologist a treatment with three cycles of systemic chemotherapy with melphalan and prednisolone was initiated but 6 months later the conjunctival mass in the inferior fornix showed persistence and complete excision was performed. At 16, 24 and 44 months of follow-up no evidence of recurrence was seen on clinical examination. The magnetic resonance imaging (MRI) at 16 and 24 months of follow-up showed no associated cranial or orbital infiltration. CONCLUSION: Conjunctival AL amyloidosis is a rare clinical entity. Because of the heterogeneity of amyloidosis in clinical presentation, pattern of amyloid-related organ toxicity, association with lymphoproliferative diseases and rate of disease progression, identification of amyloid deposits is essential and systemic involvement has to be excluded.

Multi-colour FISH in oesophageal adenocarcinoma-predictors of prognosis independent of stage and grade.

BACKGROUND: Oesophageal adenocarcinoma or Barrett's adenocarcinoma (EAC) is increasing in incidence and stratification of prognosis might improve disease management. Multi-colour fluorescence in situ hybridisation (FISH) investigating ERBB2, MYC, CDKN2A and ZNF217 has recently shown promising results for the diagnosis of dysplasia and cancer using cytological samples. METHODS: To identify markers of prognosis we targeted four selected gene loci using multi-colour FISH applied to a tissue microarray containing 130 EAC samples. Prognostic predictors (P1, P2, P3) based on genomic copy numbers of the four loci were statistically assessed to stratify patients according to overall survival in combination with clinical data. RESULTS: The best stratification into favourable and unfavourable prognoses was shown by P1, percentage of cells with less than two ZNF217 signals; P2, percentage of cells with fewer ERBB2- than ZNF217 signals; and P3, overall ratio of ERBB2-/ZNF217 signals. Median survival times for P1 were 32 vs 73 months, 28 vs 73 months for P2; and 27 vs 65 months for P3. Regarding each tumour grade P2 subdivided patients into distinct prognostic groups independently within each grade, with different median survival times of at least 35 months. CONCLUSIONS: Cell signal number of the ERBB2 and ZNF217 loci showed independence from tumour stage and differentiation grade. The prognostic value of multi-colour FISH-assays is applicable to EAC and is superior to single markers.

FOXP3+ regulatory T-cells in renal allografts: correlation with long-term graft function and acute rejection.

BACKGROUND: The interpretation of a cellular infiltrate as cytotoxic or tolerogen represents an unsolved challenge in current transplantation. The so-called regulatory CD4+ CD25+ T-cells which express the FOXP3 gene have received increasing interest with respect to this question. The existing studies concerning the role of FOXP3+ Tregs for transplant tolerance yielded contradictory results. METHODS: We examined the numbers of the FOXP3+ Tregs in two groups of renal allograft biopsies both showing cellular infiltration, but either without (n=29) or with signs of acute cellular rejection (n=26), by means of immunofluorescence and correlated the amount of FOXP3+ Tregs to renal function at the time of biopsy and after 1 and 2 years of follow up. RESULTS: The number of FOXP3+ Tregs within infiltrates in non-rejecting biopsies did not correlate with renal function after 1 and 2 years. There were no significant differences in the numbers of FOXP3+ Tregs between biopsies with or without borderline infiltrates. Increased numbers of FOXP3+ Tregs were not associated with an ameliorated severity of graft rejection and did not correlate with outcome after the rejection episode and renal function after 1 and 2 years. CONCLUSIONS: The identification of the FOXP3+ regulatory cells within the allograft cannot be considered as an appropriate marker for the interpretation of infiltrates as cytotoxic or tolerogenic or as a prognostic marker for later transplant function.

[Familial non-polyposis colorectal carcinoma (Lynch syndrome) in Germany - analysis of information, advisory service and family screening]. / "Familiärer Darmkrebs" in Deutschland. Eine Analyse von Information, Beratung und Vorsorge in Familien mit Lynch-Syndrom.

BACKGROUND: Lynch syndrome is associated with an increased incidence of colorectal carcinomas and extracolonic neoplasms. Patients fulfilling the "Revised Bethesda criteria" or the Amsterdam Citeria I or II should be screened for DNA mismatch repair deficiency. Mutation carriers and high risk individuals should undergo intensified annual screening, as recommended by the S3 guideline for colorectal carcinoma. PATIENTS AND METHODS: All families of the Regensburger study group with a verified mutation were included in this study. Data acquisition was conducted by telephone interviews. We determined the number of family members who had been informed about the diagnosis and how many of them participated in the recommended screening program. Additionally, an information letter was sent to family members providing information about the opportunity of a predictive mutation analysis. RESULTS: 90 family members of 12 families with a total of 42 carcinomas and a mean age of tumor diagnosis of 41.3 years were included. At the beginning of the study 97.4 % of the family members were informed about the diagnosis. In the course of the study the number of family members participating in the mutation analysis increased from 29.5 % to 42.3 %. The number of index patients complying with the recommended screening program was over 90 %, in contrast to the number of family members which varied between 30 - 60 %. CONCLUSIONS: Relatives of index patients are not sufficiently informed about the importance of predictive testing and the re-commended surveillance guidelines. An insufficient implementation of Lynch syndrome specific aspects of the S3-guideline can be assumed. For an improved implementation barriers of physicians' adherence must be systemically analyzed. It is essential for these high-risk families to establish and enforce awareness in order to create intensified surveillance.

[Ochronosis--a rare cause of secondary gonarthrosis]. / Ochronose--eine seltene Ursache der sekundären Gonarthrose.

Ochronosis is a manifestation of the rare disease alkaptonuria. The most common presentations include pain in the lumbar spine region starting during the 3rd decade, spreading over the large joints. There exists no curative therapy for the disease at the moment. In the long-term the patients will be dependent on total joint arthroplasty.

Upregulation of TNF receptor type 2 in human and experimental renal allograft rejection.

An important role of TNF interacting with TNFR2 has been shown in different models of ischemic, nephrotoxic and immune-mediated renal injury. To systematically evaluate the expression of TNFR2 in renal allograft rejection, we investigated human renal allograft biopsies and, in addition, established an experimental transplantation model in rats to verify the human data under standardized conditions. The expression of TNFR2 was analyzed in 96 human renal allograft biopsies with different disease entities. In a 6-day and a 28-day experimental protocol, TNFR2 was examined in kidney specimens and in the urine of control, uni-nephrectomized and transplanted rats +/- cyclosporine treatment (n = 114). In human biopsies and in rat allografts on day 6 with acute allograft rejection, significantly elevated expression of TNFR2 was observed in tubular epithelial cells, podocytes, B cells and monocytes/macrophages. The expression level was associated with renal function. The TNFR2 expression level at day 28 was significantly lower compared to day 6. TNFR2 is markedly upregulated both in human and experimental acute renal allograft rejection. Our data are robust and consistent between different species, suggesting a role for TNFR2 in the early course of rejection.

[A 42-year-old farmer with nonspecific leucocytosis and elevated transaminases. Acute septic reaction in Coxiella burnetii infection]. / 42-jähriger Landwirt mit unklarer Leukozytose und erhöhten Transaminasen. Akute septische Reaction bei Coxiella-burnetii Infektion.

We report about a 42-year-old farmer with leucocytosis, elevation of transaminases and liver cirrhosis as an underlying condition. The diagnosis of Q fever hepatitis was made through liver biopsy and serology. Under therapy with doxycycline, transaminases initially increased again; after switching to ciprofloxacin, the patient could be discharged 3 weeks after admission. Q fever is caused by Coxiella burnetii. The most frequent acute manifestation is a self-limiting flu-like illness. Chronic Q fever mostly presents as endocarditis. The diagnosis is made through histology ("doughnut" granulomas), PCR, serology (acute: anti-phase II antibodies, chronic: anti-phase I antibodies) and culture. Standard therapy is doxycycline.

SDF-1 expression is elevated in chronic human renal allograft rejection.

The exact mechanism of acute and chronic allograft rejection still remains unclear. The chemokine SDF-1 as mediator of allograft rejection has been under intensive investigation in liver, cardiac and bone marrow transplantation, whereas in renal transplantation, there are no reports about SDF-1 to date. This study was performed to evaluate if SDF-1 might also play an important role in human renal graft biopsies. One hundred and ninety formalin-fixed, paraffin-embedded renal allograft biopsies were included in the analysis from patients with normal renal graft morphology (according to Banff 97 classification grade 1, n = 84), with acute interstitial rejection (Banff grade 4 type I, n = 10), with acute vascular rejection (Banff grade 4 type II, n = 21), with chronic allograft nephropathy (CAN, Banff grade 5, n = 23), and without rejection but with various other lesions (Banff grade 6, n = 42). SDF-1 was localized by immunohistochemistry. In biopsies with CAN, SDF-1 expression was significantly elevated in interstitial infiltrates and infiltrating neointimal cells of arteries compared with biopsies with normal renal graft morphology. This is the first study describing a role of SDF-1 in human renal allograft rejection. We were able to demonstrate in a large number of biopsies an upregulation of SDF-1 in patients with CAN. Whether SDF-1 has pro-inflammatory or protective properties in this setting has to be evaluated in further trials.

Reverse diastolic intrarenal flow due to calcineurin inhibitor (CNI) toxicity.

Renal calcineurin inhibitor (CNI) toxicity is a frequent side effect of immunosuppression with CNIs in solid organ transplantation, leading to acute and chronic renal failure. Acute CNI toxicity is due to vasoconstriction of the vasa afferens and efferens and vacuolization of smooth muscle cells with medial hyalinosis, leading to vessel lumen narrowing. Our case had an acute renal failure 8 months after deceased donor kidney transplantation under treatment with tacrolimus, sirolimus and prednisolone. In Doppler sonography, we observed reverse diastolic intrarenal blood flow, reflecting intense vessel narrowing. There were histological signs of acute CNI toxicity. Within days of reducing the tacrolimus trough level, renal function improved markedly and Doppler sonography showed orthograde intrarenal blood flow. This is the first case of functional, Doppler sonographic evidence for CNI-induced, rapidly reversible narrowing of intrarenal vessels. This case illustrates the potential role of tacrolimus and sirolimus dosing in combination therapy to produce severe intrarenal vasoconstriction.

[A new quantitative DNA-methylation analysis of MSI colorectal cancers helps to separate sporadic colorectal cancers from HNPCC-candidates]. / Eine neue, robuste und präzise real-time PCR Methode zur quantitativen Bestimmung von Promotor DNA-Methylierung als ein hilfreiches Mittel zur Unterscheidung vom sporadischen kolorektalen Karzinom und HNPCC.

AIMS: Promoter hypermethylation is a common mechanism for epigenetic control of gene expression and occurs frequently in tumors silencing tumor suppressor genes. Our aim was to establish a quantitative and precise method to analyze promoter methylation of tumor samples in order to identify HNPCC candidates. METHODS: We established a new methylation specific relative quantitative real-time PCR technique for analysis of the methylation status of the hMLHI promoter in colorectal cancers (CRC). We determined methylation status of both the distal and proximal hMLH1-promoter region. The methylation quantification (MQ) was performed with cell line DNA and archival paraffinized tissue sections. RESULTS: The accuracy of our analysis was validated with spiking experiments of methylated and unmethylated DNA. We assessed the hMLH1 methylation status 56 CRC patients with known microsatellite status and hMLH1 IHC. The methylation analysis divided the MSI-H CRC into two groups: Methylation positive sporadic CRC patients with a median age of 78.5 years and frequent BRAF mutations (82 %, p < 0.0001) and the unmethylated cancers from HNPCC candidates with a median age of 48 years. All hMLH1 positive sporadic MSS CRC were methylation negative. In all samples, the degree of methylation was mirrored by the shift of the melting points to higher temperatures. CONCLUSIONS: In summary we introduced a quantitative and qualitative technique to analyze DNA methylation that can be performed with any dense CpG island. Our methylation analysis provides a potent diagnostic tool to differentiate between sporadic MSI-H cancers showing MLH1 methylation and MLH1 unmethylated HNPCC candidates.

Barrett's esophagus: a discrepancy between macroscopic and histological diagnosis.

BACKGROUND AND STUDY AIMS: The diagnosis of Barrett's esophagus at present requires endoscopic and histological confirmation of specialized intestinal metaplasia. This study prospectively analyzed the endoscopic and histological prevalence of Barrett's esophagus and the risk factors for the presence of Barrett's esophagus among patients being treated in an endoscopy unit. PATIENTS AND METHODS: A total of 474 unselected patients (58% men; mean age 52 y) were included in the study. Two biopsy specimens each were taken from below and above the squamocolumnar junction and from the antrum and gastric body. Four-quadrant biopsies were taken every 1-2 cm to confirm a macroscopic suspicion of Barrett's esophagus. RESULTS: Barrett's esophagus was suspected at endoscopy in 109 patients (23%). Of the 109 patients with endoscopically suspected Barrett's esophagus, only 46 (42%) had the finding confirmed histologically. The sensitivity and specificity for the endoscopic diagnosis of Barrett's esophagus were 62% and 84%, respectively. A multivariate logistic regression analysis identified age (P = 0.0001; odds ratio per life-year 1.087; 95% CI, 1.046-1.139), male sex (P = 0.0020; OR 6.346; 95% CI, 2.094-22.314), and the number of biopsies (P = 0.0025; OR 1.661; 95% CI, 1.247-2.392) as factors associated with evidence of intestinal metaplasia on biopsy. CONCLUSION: The striking discrepancy between the endoscopic findings and the histological diagnosis may be due to the focal distribution of intestinal metaplasia. This emphasizes the importance of an adequate biopsy protocol. In addition, better methods of detecting focal islands of intestinal metaplasia that are not visible at conventional endoscopy are needed.

Mitral prolapse caused by lymphangioma.

A 62-year-old female patient with known mitral-valve prolapse for the previous five years presented with progressive dyspnea and intermittent palpitations. This clinical presentation was investigated by two-dimensional echocardiography which revealed moderate mitral regurgitation due to a pedunculated mass oscillating between the left atrium and the left ventricle. Successful operative treatment consisted of en-bloc resection of the tumor from the anterior mitral valve leaflet and its primary cords and subsequent reconstruction of the mitral valve. Pathohistological examination revealed a cystic lymphangioma originating from mitral-valve tissue. To our knowledge this is the first reported case in the literature.

Analysis of intestinal haem-oxygenase-1 (HO-1) in clinical and experimental colitis.

Haem-oxygenase-1 (HO-1) has been shown to exert anti-inflammatory, anti-apoptotic and anti-proliferative effects. We investigated HO-1 expression in patients with inflammatory bowel disease (IBD) and could demonstrate a scattered expression of HO-1 in the intestinal epithelium of severely inflamed colonic mucosa of patients with IBD compared to control specimens such as diverticulitis, suggesting dysregulated expression in IBD. To further analyse potential mechanisms of HO-1 induction in the intestine we employed an in vitro epithelial cell apoptosis model and an experimental colitis model. In vitro induction of HO-1 by the HO-1 inducer cobalt protoporphyrin (CoPP) resulted in a dose-dependent down-regulation of caspase-3 activation in HT-29 cells, indicating an anti-apoptotic function of HO-1 in the intestine. In vivo, preventive HO-1 induction by CoPP in acute dextran sodium sulphate (DSS)-induced colitis led to a significant down-regulation of colonic inflammation (P < 0.01) with a concomitant reduction in interferon (IFN)-gamma - but unaffected interleukin (IL)-10-secretion by isolated mesenteric lymph nodes (P < 0.01). Additionally, TUNEL staining of colonic sections demonstrated fewer apoptotic epithelial cells in the colon of CoPP treated animals. No beneficial effects were observed if HO-1 was induced by CoPP after the onset of acute colitis or in chronic DSS-induced colitis. In conclusion, the data suggest a protective role of HO-1 if it is induced before the onset of inflammation. However, as shown by the lack of effects in established acute or in chronic colitis, the induction of HO-1 may not be a promising approach for the treatment of IBD.

Quantitative gene expression analysis of fractalkine using laser microdissection in biopsies from kidney allografts with acute rejection.

Percutaneous biopsy of the kidney remains the gold standard to establish a diagnosis in renal diseases. Only semiquantitative assessments of gene expression on biopsies have been possible so far. We studied gene expression of the chemokine fractalkine (FKN) in 12 biopsies from laser microdissected kidney allografts that showed histologic signs of acute rejection and 10 controls. As quantified by real-time PCR, the relative tubular FKN expression increased from 1.0 [0.81 to 2.95] (median [range]) in controls to 12.44 [0.90 to 191.0] in acute rejection (P < .01); glomerular FKN expression from 1.3 [0.07 to 27.44] to 12.22 [1.32 to 50.23] (P < .05); and vascular expression, from 0.72 [0.37 to 5.11] to 7.07 [1.19 to 73.49] (P < .01). Furthermore, there was a trend toward higher glomerular FKN expression among patients with more severe rejection. Our results suggest a role of FKN in acute renal allograft rejection.

Morphological characterisation of Crohn's disease fistulae.

BACKGROUND: Fistulae are a common complication in up to 35% of all patients with Crohn's disease. Their therapy is difficult and frequently unsatisfactory. To date, no histological comparison of Crohn's disease fistulae with non-inflammatory bowel disease fistulae has been performed. In addition, Crohn's disease fistulae have not been well characterised morphologically. METHODS: Eighty four fistulae from Crohn's disease patients were compared with 13 fistulae from controls. Haematoxylin-eosin staining, electron microscopy, and immunohistochemistry for panCytokeratin (epithelial cells), CD20 (B cells), CD45R0 (T cells), and CD68 (macrophages) were performed according to standard techniques. In addition, histopathological findings were compared with clinical and laboratory data. RESULTS: In 31.0% of controls and 27.4% of Crohn's disease specimens, fistulae had a lining of flattened intestinal epithelium without goblet cells or, in the case of cutaneous/perianal disease, narrow squamous epithelium. Non-epithelialised fistulae were covered by a thin layer of (myo)fibroblasts, focally forming a new basement membrane, as demonstrated by electron microscopy. All fistulae were surrounded by granulation tissue. Crohn's disease fistulae presented with central infiltration by CD45R0+ T cells, followed by a small band of CD68+ macrophages and dense accumulation of CD20+ B cells. In contrast, in controls, there was dense infiltration by CD68+ macrophages with only few CD20+ B cells and CD45R0+ T lymphocytes. CONCLUSIONS: Fistulae in Crohn's disease differ markedly from non-Crohn's disease fistulae with regard to their cellular composition. The presence of an epithelial lining in a subgroup of fistulae may be important for the therapeutic approach and healing process.

[Endoscopic mucosal resection for early esophageal cancer with esophageal varices]. / Endoskopische Mukosaresektion eines Osophagusfrühkarzinoms bei Leberzirrhose und Osophagusvarizen.

Squamous cell carcinomas account for more than 80 % of esophageal malignancies in Germany. Alcohol and tobacco smoke are two of the most important risk factors. In superficial esophageal squamous cell carcinoma, endoscopic mucosal resection (EMR) is a very useful and effective treatment modality. However, in patients with submucosal esophageal cancer, radical esophageal resection is regarded as the gold standard for treatment at present. We report the case of a 71-year-old female patient with alcohol-induced liver cirrhosis with esophageal varices and a - therefore inoperable - early esophageal squamous cell carcinoma. Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) seemed not to be an effective treatment modality due to its limited penetration depth (< 2 mm) and the liver toxicity of 5-ALA. PDT using Photofrin(R) with a higher penetration depth seemed to be associated with a high risk of bleeding due to the esophageal varices. Furthermore, this sensitizer is associated with a high rate of strictures and a long-lasting skin sensitivity. In contrast, arguments against an endoscopic mucosal resection (EMR) were endosonographically suspected submucosal tumor growth and a high risk of bleeding. Nevertheless, with respect to the lack alternatives we decided to perform an EMR after ligation of esophageal varices. The tumor could be resected in sano without major bleeding complication. Histology demonstrated a carcinoma in situ without submucosal invasion. After 3 months a second EMR was necessary due to recurrence. Meanwhile after a follow-up period of 18 months only low grade intraepithelial neoplasia without macroscopically suspicious lesions was observed.

["Adult form" of congenital liver fibrosis]. / "Adulte Form" der kongenitalen Leberfibrose.

HISTORY AND ADMISSION FINDINGS: During a routine check-up, a 37-year-old woman was found to have elevated levels of serum gamma-glutamyl transferase (gamma GTP) and IgA- and IgM-antibodies. One of the patient's brothers had died at the age of six from acute liver failure. We found a palpably enlarged liver with normal consistency and no particular helpful laboratory results. INVESTIGATIONS: The abdominal ultrasound and computed tomography (CT) showed segmental and saccular dilatations of the biliary tract, hepatofugal flow in the portal vein, multiple collateral vessels as well as a mild splenomegaly. Histopathology revealed fibrotic liver parenchyma, a dilatated and branched biliary tract lined by cubical epithelium. COURSE: Gastroscopy showed lowgrade esophageal varices. Seventeen months after the initial presentation there were no significant changes of the laboratory tests or the ultrasound. CONCLUSIONS: The defective remodelling of the ductal plate ("ductal plate malformation") is associated with dysplasia of the biliary tract. Depending on the localisation of the lesions within the biliary tract and whether it is a more cystic or more fibrotic component, there are different malformations caused by ductal plate malformation. We diagnosed congenital hepatic fibrosis, because of the atypical age of presentation, it could be the "adult form" of congenital liver fibrosis.

[Molecular pathology in hereditary colorectal cancer. Recommendations of the Collaborative German Study Group on hereditary colorectal cancer funded by the German Cancer Aid (Deutsche Krebshilfe)]. / Molekularpathologische Diagnostik beim erblichen Dickdarmkarzinom. Empfehlungen und Resultate aus dem Verbundprojekt der Deutschen Krebshilfe "Krebsvorsorge und Krebsfrüherkennung bei Familiärem Darmkrebs".

Although twin studies indicate that inherited genetic factors contribute to about 35% of colorectal cancers (CRC), the exact genetic background has currently been elucidated in only 5-10% of cases. These comprise several hereditary cancer predisposition syndromes that present with a high number of syn- or metachronous neoplasms within an affected person and/or family. Many of these tumors exhibit typical histopathological changes. In general, one should discriminate between cancer syndromes associated with adenomatous and non-adenomatous (i.e., hamartomatous) polyps, the latter being quite rare. The patient's age often serves as a substantial hint to hereditary cancer. The next step of diagnostic work-up includes analysis of microsatellite instability (MSI) together with immunohistochemical detection of a loss of expression in one of the most frequently affected mismatch repair genes (MSH2, MSH6; MLH1, PMS2). Finally, the molecular demonstration of a gene mutation in the blood or germline is the most expensive and tedious procedure. This requires a signed informed consent from the patient after appropriate genetic counseling.