BACKGROUND: Hypercholesterolemia-induced endothelial dysfunction due to excessive production of reactive oxygen species is a major trigger of atherogenesis. The c-Jun-N-terminal kinases (JNKs) are activated by oxidative stress and play a key role in atherogenesis and inflammation. We investigated whether JNK2 deletion protects from hypercholesterolemia-induced endothelial dysfunction and oxidative stress. METHODS AND RESULTS: Male JNK2 knockout (JNK2(-/-)) and wild-type (WT) mice (8 weeks old) were fed either a high-cholesterol diet (HCD; 1.25% total cholesterol) or a normal diet for 14 weeks. Aortic lysates of WT mice fed a HCD showed an increase in JNK phosphorylation compared with WT mice fed a normal diet (P<0.05). Endothelium-dependent relaxations to acetylcholine were impaired in WT HCD mice (P<0.05 versus WT normal diet). In contrast, JNK2(-/-) HCD mice did not exhibit endothelial dysfunction (96+/-5% maximal relaxation in response to acetylcholine; P<0.05 versus WT HCD). Endothelium-independent relaxations were identical in all groups. A hypercholesterolemia-induced decrease in nitric oxide (NO) release of endothelial cells was found in WT but not in JNK2(-/-) mice. In parallel, endothelial NO synthase expression was upregulated only in JNK2(-/-) HCD animals, whereas the expression of antioxidant defense systems such as extracellular superoxide dismutase and manganese superoxide dismutase was decreased in WT but not in JNK2(-/-) HCD mice. In contrast to JNK2(-/-) mice, WT HCD displayed an increase in O(2)(-) and ONOO(-) concentrations as well as nitrotyrosine staining and peroxidation. CONCLUSIONS: JNK2 plays a critical role as a mediator of hypercholesterolemia-induced endothelial dysfunction and oxidative stress. Thus, JNK2 may provide a novel target for prevention of vascular disease and atherosclerosis. DOI: https://doi.org/10.1161/CIRCULATIONAHA.108.765032 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-11304 Accepted Version Originally published at: Osto, E; Matter, C M; Kouroedov, A; Malinski, T; Bachschmid, M; Camici, G G; Kilic, U; Stallmach, T; Boren, J; Iliceto, S; Lüscher, T F; Cosentino, F (2008). c-Jun N-terminal kinase 2 deficiency protects against hypercholesterolemia-induced endothelial dysfunction and oxidative stress. Circulation, 118(20):2073-2080. DOI: https://doi.org/10.1161/CIRCULATIONAHA.108.765032 JNK2 Deficiency Protects Against Hypercholesterolemia-Induced Endothelial Dysfunction and Oxidative Stress Elena Osto MD, Christian M. Matter MD, 1,2 Alexey Kouroedov MD, PhD, Tadeusz Malinski PhD, Markus Bachschmid PhD, 1,2 Giovanni Camici PhD, 1,2 Ulkan Kilic PhD, Thomas Stallmach MD, Jan Boren PhD, 7 Sabino Iliceto MD, Thomas F. Luscher MD, Francesco Cosentino MD, PhD Cardiology and Cardiovascular Research, Institute of Physiology and University Hospital; Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Switzerland; Department of Biochemistry, Ohio University, Athens, Ohio; Department of Medicine, Boston University School of Medicine, Boston, Massachusetts; Department of Pathology, University Hospital, Zurich, Switzerland; Wallenberg Laboratory Sahlgrenska Academy, Goteborg, Sweden, 7 Cardiology, University of Padua, Cardiology, 2 Faculty of Medicine, University “Sapienza”, Rome, Italy, Running title: Role of JNK2 in endothelial dysfunction Address for Correspondence: Francesco Cosentino, M.D., Ph.D. Cardiology & Cardiovascular Research Institute of Physiology University of Zurich-Irchel Winterthurerstrasse, 190 CH-8057 Zurich, Switzerland Tel: 41-44-635 5097 Fax: 41-44-635 6827 Email: f_cosentino@hotmail.com

Pathologe 2015 · 36:98 DOI 10.1007/s00292-014-2070-4 © Springer-Verlag Berlin Heidelberg 2015 Dank an die Gutachter … Dr. Christian August, Münster Prof. Dr. Hideo Baba, Essen Prof. Dr. Agnes Bankfalvi, Essen Prof. Dr. Gustavo Baretton, Dresden Prof. Dr. Erhard Bierhoff, Bonn Prof. Dr. Hendrik Bläker, Berlin Dr. Thomas Brenn, Edinburgh Prof. Dr. Lukas Bubendorf, Basel Dr. Henning Feist, Flensburg Prof. Dr. Falko Fend, Tübingen Prof. Dr. Ludger Fink, Giessen Prof. Dr. Hans-Peter Fischer, Bonn Prof. Dr. Annette Fisseler- Eckhoff, Wiesbaden Prof. Dr. Stefan Gattenlöhner, Giessen Dr. Klaus Griewank, Essen Prof. Dr. Arndt Hartmann, Erlangen PD Dr. Kathrin Hauptmann, Berlin Prof. Dr. Ferdinand Hofstädter, Regensburg Prof. Dr. Gernot Jundt, Basel Prof. Dr. Ruth Knüchel-Clarke, Aachen PD Dr. Andreas Kreft, Mainz Prof. Dr. Cornelius Kuhnen, Münster … Dr. Florian Laenger, Hannover Dr. Cord Langner, Graz Prof. Dr …

Intestinal dendritic cells (DCs) are believed to sample and present commensal bacteria to the gut-associated immune system to maintain immune homeostasis. How antigen sampling pathways handle intestinal pathogens remains elusive. We present a murine colitogenic Salmonella infection model that is highly dependent on DCs. Conditional DC depletion experiments revealed that intestinal virulence of S. Typhimurium SL1344 Delta invG mutant lacking a functional type 3 secretion system-1 (Delta invG) critically required DCs for invasion across the epithelium. The DC-dependency was limited to the early phase of infection when bacteria colocalized with CD11c(+)CX3CR1(+) mucosal DCs. At later stages, the bacteria became associated with other (CD11c(-)CX3CR1(-)) lamina propria cells, DC depletion no longer attenuated the pathology, and a MyD88-dependent mucosal inflammation was initiated. Using bone marrow chimeric mice, we showed that the MyD88 signaling within hematopoietic cells, which are distinct from DCs, was required and sufficient for induction of the colitis. Moreover, MyD88-deficient DCs supported transepithelial uptake of the bacteria and the induction of MyD88-dependent colitis. These results establish that pathogen sampling by DCs is a discrete, and MyD88-independent, step during the initiation of a mucosal innate immune response to bacterial infection in vivo.

Many genetic diseases have been linked to the dysfunction of primary cilia, which occur nearly ubiquitously in the body and act as solitary cellular mechanosensory organelles. The list of clinical manifestations and affected tissues in cilia-related disorders (ciliopathies) such as nephronophthisis is broad and has been attributed to the wide expression pattern of ciliary proteins. However, little is known about the molecular mechanisms leading to this dramatic diversity of phenotypes. We recently reported hypomorphic NPHP3 mutations in children and young adults with isolated nephronophthisis and associated hepatic fibrosis or tapetoretinal degeneration. Here, we chose a combinatorial approach in mice and humans to define the phenotypic spectrum of NPHP3/Nphp3 mutations and the role of the nephrocystin-3 protein. We demonstrate that the pcy mutation generates a hypomorphic Nphp3 allele that is responsible for the cystic kidney disease phenotype, whereas complete loss of Nphp3 function results in situs inversus, congenital heart defects, and embryonic lethality in mice. In humans, we show that NPHP3 mutations can cause a broad clinical spectrum of early embryonic patterning defects comprising situs inversus, polydactyly, central nervous system malformations, structural heart defects, preauricular fistulas, and a wide range of congenital anomalies of the kidney and urinary tract (CAKUT). On the functional level, we show that nephrocystin-3 directly interacts with inversin and can inhibit like inversin canonical Wnt signaling, whereas nephrocystin-3 deficiency leads in Xenopus laevis to typical planar cell polarity defects, suggesting a role in the control of canonical and noncanonical (planar cell polarity) Wnt signaling.

Background— Hypercholesterolemia-induced endothelial dysfunction due to excessive production of reactive oxygen species is a major trigger of atherogenesis. The c-Jun-N-terminal kinases (JNKs) are activated by oxidative stress and play a key role in atherogenesis and inflammation. We investigated whether JNK2 deletion protects from hypercholesterolemia-induced endothelial dysfunction and oxidative stress. Methods and Results— Male JNK2 knockout ( JNK2 −/− ) and wild-type (WT) mice (8 weeks old) were fed either a high-cholesterol diet (HCD; 1.25% total cholesterol) or a normal diet for 14 weeks. Aortic lysates of WT mice fed a HCD showed an increase in JNK phosphorylation compared with WT mice fed a normal diet ( P <0.05). Endothelium-dependent relaxations to acetylcholine were impaired in WT HCD mice ( P <0.05 versus WT normal diet). In contrast, JNK2 −/− HCD mice did not exhibit endothelial dysfunction (96±5% maximal relaxation in response to acetylcholine; P <0.05 versus WT HCD). Endothelium-independent relaxations were identical in all groups. A hypercholesterolemia-induced decrease in nitric oxide (NO) release of endothelial cells was found in WT but not in JNK2 −/− mice. In parallel, endothelial NO synthase expression was upregulated only in JNK2 −/− HCD animals, whereas the expression of antioxidant defense systems such as extracellular superoxide dismutase and manganese superoxide dismutase was decreased in WT but not in JNK2 −/− HCD mice. In contrast to JNK2 −/− mice, WT HCD displayed an increase in O 2 − and ONOO − concentrations as well as nitrotyrosine staining and peroxidation. Conclusions— JNK2 plays a critical role as a mediator of hypercholesterolemia-induced endothelial dysfunction and oxidative stress. Thus, JNK2 may provide a novel target for prevention of vascular disease and atherosclerosis.

Renal tubular dysgenesis (RTD) is a clinical disorder either acquired during fetal development or inherited as an autosomal recessive condition. Inherited RTD is caused by mutations in the genes encoding the components of the renin-angiotensin system angiotensinogen, renin, angiotensin-converting enzyme and angiotensin II receptor type 1. Inherited RTD is characterized by early onset oligohydramnios, skull ossification defects, preterm birth and neonatal pulmonary and renal failure. The histological hallmark is the absence or poor development of proximal tubules. So far, all patients died either in utero or shortly after birth. We report the first patients with inherited RTD surviving the neonatal period and still being alive. Genetic and functional analysis of the renin-angiotensin system contributes to the diagnosis of RTD. In conclusion, the clinical diagnosis of inherited RTD is easily missed after birth without renal biopsy or information on affected family members. Genetic and functional analysis of the renin-angiotensin system contributes to correct diagnosis.

Aims: Amniotic infection (AI) and preeclampsia (PE), which are commonly the reason for prematurity, inflict stress of different duration on immature fetuses. Whether chronic stress, as reflected by intrauterine growth retardation, influences the level of 17-OH progesterone (17-OHP), was not previously examined.Methods: We analyzed 17-OHP and TSH levels during neonatal screenings in the first hours of life of 90 premature infants born between 25 and 33 weeks of gestation in infants with AI (n =37) or with PE (n =53). Control of acute stress parameters was derived from umbilical arterial cord blood pH and base excess (BE).Results: Mean 17-OHP levels of infants born to mothers with PE were 85.7 nmol/L compared to 54.6 nmol/L (P<0.001) in AI infants. 17-OHP was even higher when intrauterine growth restriction was present (99.8 nmol/L). Antenatal steroids and mode of delivery did not significantly affect 17-OHP levels.Conclusions: Stress of relatively long duration, as in cases of PE, leads to a significant increase of 17-OHP level in preterm infants. The postnatal 17-OHP level may be considered as a measure for severity of intrauterine stress and might be used as an individualized indicator for earlier intensive care.

We postulate that repeated pregnancy loss, intrauterine growth restriction, and preeclampsia are caused by impaired elevation of uterine blood flow due to disturbed arteriogenesis of the uterine arcade. This hypothesis is based on the observation that pregnant human erythropoietin-overexpressing (plasma levels elevated 12-fold) mice (termed tg6 mice) suffering from excessive erythrocytosis generally abort at midgestation unless their hematocrit of 0.85 is drastically lowered. Transgenic mice show placental malformations that parallel those observed in pregnant women suffering from impaired uterine perfusion. Shear stress, a key factor inducing arteriogenesis, was 5-fold lower in tg6 mice compared with wildtype (WT) littermates. Consequently, uterine artery growth was reduced, and dramatically fewer viable pups (1.63 +/- 2.20 vs. 8.10 +/- 0.74 in WT) of lower weight (1.29 +/- 0.07 g vs. 1.62 +/- 0.12 g in WT) were delivered in first pregnancies. Only in subsequent pregnancies did tg6 deliver approximately the expected number of pups. Birth weights of tg6 offspring, however, remained reduced. As the spleen is a major site of extramedullary erythropoiesis in tg6 animals, splenectomy reduced the hematocrit to 0.6-0.7. In turn, shear stress increased to normal values, and splenectomized primiparous tg6 showed normal uterine artery growth and delivery of pups similar in number and weight compared with WT. We conclude that poor arteriogenesis is a previously unappreciated cause for clinically important pregnancy complications.

Fragestellung: Der plötzliche intrauterine Fruchttod (SIUD) in Terminnähe tritt in 0.1–0.2% aller als risikoarm eingestuften Schwangerschaften auf und ist somit ein Hauptfaktor der perinatalen Mortalität. Ein plazentarer Endzottenmagel ist möglicherweise eine der Ursachen des SIUD.

We present a neonate with heterotopic nasopharyngeal brain tissue causing airway obstruction. Preoperative imaging showed extension of the mass along major neurovascular pathways into the cranial vault. Preoperative identification of intracranial extension is essential for planning surgery to prevent postoperative cerebrospinal fluid leaks or possible meningitis.

In this paper, a boy is reported with the association of congenital analbuminemia (CAA) and steroid-sensitive idiopathic nephrotic syndrome (INS), two conditions resulting independently in reduced colloid oncotic pressure. The unique occurrence helps confirm earlier reports that albumin is not the exclusive factor responsible for maintaining colloid oncotic pressure.

Clinical informationA 35-year-old woman, gravida 3, para 3, at 33 1/7 weeks ofgestation was referred to the obstetric clinic for prenatalassessment of an echogenic mass of the umbilical corddetected during a routine ultrasound examination. Chori-onic villus biopsy for advanced maternal age at 13-weekgestation revealed a normal 46 XX karyotype. Sonographicassessment of the fetus demonstrated growth parametersappropriate for the gestational age. The abdominal wall wasclosed, with an inhomogeneous mass measuring 43×32×28 mm near the insertion of the umbilical cord (Fig. 1). Thecardiotocogram showed no fetal distress. Doppler flowstudies of the umbilical cord showed three vessels,displaced by a multilobulated echogenic tumor. Maternalserum screening showed an elevated level of alpha-fetoprotein (326 μg/l), but no signs of congenital infection.At 38 5/7 weeks of gestation, a girl was deliveredvaginally, weighing 2,840 g (10th–25th centile), with alength of 47 cm (10th–25th centile) and head circumfer-ence of 33 cm (10th–25th centile). She adapted with Apgarscores of 8/9/9, and the arterial cord pH was 7.31. Theumbilical cord showed a nodular bulge proximal to itsinsertion into the abdominal wall. It measured 4 cm indiameter, had a smooth, translucent, pearly colored surface,without superficial vessels or pulsations, and was of firm,elastic consistency. A blue core was discernible within(Fig. 2). The findings were associated with markedthickening and edema of the Wharton’s jelly, and one veinand two arteries were present within the cord. A 1-cmsegment of normal umbilical cord separated the tumor fromthe intact abdominal wall. Abdominal ultrasound examina-tion showed no visceral abnormalities. The umbilical cordwas clamped distal to the lesion, and the infant recovered ina puerperal care unit. The macro- and microscopic placentaexamination (387 g, 19×15×3 cm) revealed no abnormal-ities. At 2 days of age, the infant was transferred to apediatric surgery unit for surgical revision.

In view of the emerging role of recombinant human erythropoietin (rhEPO) as a novel therapeutical approach in myocardial ischemia, we performed the first two-way parallel comparison to test the effects of rhEPO pretreatment (1000 U/kg, 12h before surgery) versus EPO transgenic overexpression in a mouse model of myocardial infarction. Unlike EPO transgenic mice who doubled their hematocrit, rhEPO pretreated mice maintained an unaltered hematocrit, thereby offering the possibility to discern erythropoietic-dependent from erythropoietic-independent protective effects of EPO. Animals pretreated with rhEPO as well as EPO transgenic mice underwent permanent left anterior descending (LAD) coronary artery ligation. Resulting infarct size was determined 24h after LAD ligation by hematoxylin/eosin staining, and morphometrical analysis was performed by computerized planimetry. A large reduction in infarction size was observed in rhEPO-treated mice (-74% +/- 14.51; P = 0.0002) and an even more pronounced reduction in the EPO transgenic group (-87% +/- 6.31; P < 0.0001) when compared to wild-type controls. Moreover, while searching for novel early ischemic markers, we analyzed expression of hypoxia-sensitive Wilms' tumor suppressor gene (WT1) in infarcted hearts. We found that its expression correlated with the infarct area, thereby providing the first demonstration that WT1 is a useful early marker of myocardial infarction. This study demonstrates for the first time that, despite high hematocrit levels, endogenously overexpressed EPO provides protection against myocardial infarction in a murine model of permanent LAD ligation.

Joubert syndrome (JS) is an autosomal recessive disorder, consisting of mental retardation, cerebellar vermis aplasia, an irregular breathing pattern, and retinal degeneration. Nephronophthisis (NPHP) is found in 17-27% of these patients, which was designated JS type B. Mutations in four separate genes (AHI1, NPHP1, CEP290/NPHP6, and MKS3) are linked to JS. However, missense mutations in a new ciliary gene (RPGRIP1L) were found in type B patients. We analyzed a cohort of 56 patients with JS type B who were negative for mutations in three (AHI1, NPHP1, and CEP290/NPHP6) of the four genes previously linked to the syndrome. The 26 exons encoding RPGRIP1L were analyzed by means of PCR amplification, CEL I endonuclease digestion, and subsequent sequencing. Using this approach, four different mutations in the RPGRIP1L gene in five different families were identified and three were found to be novel mutations. Additionally, we verified that missense mutations are responsible for JS type B and cluster in exon 15 of the RPGRIP1L gene. Our studies confirm that a T615P mutation represents the most common mutation in the RPGRIP1L gene causing disease in about 8-10% of JS type B patients negative for NPHP1, NPHP6, or AHI1 mutations.

Background Hypercholesterolemia-induced endothelial dysfunction (ED) is a major trigger for atherosclerosis. The c-Jun-N-terminal kinases (JNKs) belong to the mitogen-activated protein kinase family. Genetic deletion of JNK2 has been shown to decrease atheroma formation. The present study was designed to investigate whether hypercholesterolemic JNK2 knockout ( JNK2 −/− ) mice are protected from oxidative stress-induced ED. Methods and Results Male JNK2 −/− and corresponding wild-type (WT) mice (8 weeks old) were fed either a high cholesterol diet (HCD, 1.25% total cholesterol) or normal chow (controls) for 14 weeks. WT mice fed a HCD showed a 2-fold increase in JNK phosphorylation as assessed by Western blotting (n=4 – 6, p<0.05 vs. controls). In parallel, endothelium-dependent relaxations to acetylcholine (Ach, 10 −9 -10 −6 mol/L) were impaired in WT mice exposed to a HCD as compared to WT controls (n=4 – 6 in each groups, p<0.05). In contrast, JNK2 −/− mice did not exhibit hypercholesterolemia-induced ED (96±5% max relaxation to Ach, n=4 – 6, p<0.05 vs. WT HCD). Endothelium-independent relaxations to sodium nitroprusside (10 −10 -10 −5 mol/L) were identical in all groups. Nitric oxide release, measured by nanosensors in single aortic endothelial cells, was decreased in WT but not in JNK2 −/− HCD mice (121 vs. 253 nmol/L in WT and JNK2 −/− HCD mice, respectively, n=4 – 6, p<0.05). Indeed, WT HCD mice displayed a marked increase in peroxynitrite (ONOO − ) generation, nitrotyrosine expression,and lipid peroxidation (n=4 – 6 in each groups, p<0.05 vs. WT and JNK2 −/− control as well as JNK2 −/− HCD mice). Deletion of the JNK2 gene prevented this hypercholesterolemia-induced increase in oxidative stress. Furthermore, expression of antioxidant defense systems such as manganese and extracellular superoxide dismutase as well as heme-oxygenase activity was significantly decreased in WT, but not in JNK2 −/− HCD mice (n=4 – 6, p<0.05). Conclusions These data suggest that genetic deletion of JNK2 protects against hypercholesterolemia-induced oxidative stress and endothelial dysfunction. Thus, inhibition of JNK2 may represent a novel therapeutic target to prevent initiation of atherogenesis.

The viability of the human fetus increases significantly beyond 25 weeks’ gestation as the lung development progresses towards the ‘saccular’ stage. We report on a fetus of 22 weeks’ gestation whose lung maturation was accelerated by 4 weeks, most likely due to the unintentional exposure to the retinoid isotretinoin (13-cis-retinoic acid) during pregnancy. Although retinoids are known to be stored within the lungs and to play a key role in lung differentiation and growth, their storage within the lung is limited during this critical developmental period. Even though glucocorticosteroids are used clinically to enhance lung maturation in the face of impending preterm birth, there are no data yet which demonstrate that glucocorticosteroids, when given alone, are effective in promoting lung maturation prior to 24 weeks’ gestation. Strong evidence however, indicates that glucocorticosteroids promote the utilization of lung retinoids immediately before birth. Our observation of increased lung maturation, in conjunction with the above information suggests that retinoids alone or in combination with glucocorticosteroids might promote lung maturation more effectively than glucocorticosteroids alone when birth seems inevitable at a very early gestational age.

ABSTRACTSalmonella entericasubspecies I serovars are common bacterial pathogens causing diseases ranging from enterocolitis to systemic infections. Some serovars are adapted to specific hosts, whereas others have a broad host range. The molecular mechanisms defining the virulence characteristics and the host range of a givenS. entericaserovar are unknown. Streptomycin pretreated mice provide a surrogate host model for studying molecular aspects of the intestinal inflammation (colitis) caused by serovar Typhimurium (S. Hapfelmeier and W. D. Hardt, Trends Microbiol. 13:497-503, 2005). Here, we studied whether this animal model is also useful for studying otherS. entericasubspecies I serovars. All three tested strains of the broad-host-range serovar Enteritidis (125109, 5496/98, and 832/99) caused pronounced colitis and systemic infection in streptomycin pretreated mice. Different levels of virulence were observed among three tested strains of the host-adapted serovar Dublin (SARB13, SD2229, and SD3246). Several strains of host restricted serovars were also studied. Two serovar Pullorum strains (X3543 and 449/87) caused intermediate levels of colitis. No intestinal inflammation was observed upon infection with three different serovar Paratyphi A strains (SARB42, 2804/96, and 5314/98) and one serovar Gallinarum strain (X3796). A second serovar Gallinarum strain (287/91) was highly virulent and caused severe colitis. This strain awaits future analysis. In conclusion, the streptomycin pretreated mouse model can provide an additional tool to study virulence factors (i.e., those involved in enteropathogenesis) of variousS. entericasubspecies I serovars. Five of these strains (125109, 2229, 287/91, 449/87, and SARB42) are subject ofSalmonellagenome sequencing projects. The streptomycin pretreated mouse model may be useful for testing hypotheses derived from this genomic data.

ABSTRACT Salmonella enterica subspecies 1 serovar Typhimurium is an enteric bacterial pathogen infecting a broad range of hosts. In susceptible Nramp1 − / − ( Slc11α1 − / − ) mice, serovar Typhimurium cannot efficiently colonize the intestine but causes a systemic typhoid-like infection. However, after pretreatment with streptomycin, these susceptible (C57BL/6 and BALB/c) mice develop acute serovar Typhimurium-induced colitis (M. Barthel et al., Infect. Immun. 71: 2839-2858, 2003). It was not clear whether resistant Nramp1 +/+ ( Slc11α1 +/+ ) mouse strains would similarly develop colitis. Here we compared serovar Typhimurium infection in streptomycin-pretreated susceptible (C57BL/6) and resistant (DBA/2 and 129Sv/Ev) mouse strains: We found that acute colitis (days 1 and 3 postinfection) is strikingly similar in susceptible and resistant mice. In 129Sv/Ev mice we followed the serovar Typhimurium infection for as long as 6 weeks. After the initial phase of acute colitis, these animals developed chronic crypt-destructive colitis, including ulceration, crypt abscesses, pronounced mucosal and submucosal infiltrates, overshooting regeneration of the epithelium, and crypt branching. Moreover, we observed inflammation of the gall duct epithelium (cholangitis) in the 129Sv/Ev mice between days 14 and 43 of infection. Cholangitis was not attributable to side effects of the streptomycin treatment. Furthermore, chronic infection of 129Sv/Ev mice in a typhoid fever model did not lead to cholangitis. We propose that streptomycin-pretreated 129Sv/Ev mice provide a robust murine model for chronic enteric salmonellosis including complications such as cholangitis.

Inactivation of the HRPT2 gene encoding parafibromin was recently linked to the familial hyperparathyroidism-jaw tumor syndrome. Patients with this syndrome carry an increased risk of parathyroid and renal tumors. To determine the relevance of HRPT2 for sporadic renal tumors, clear cell, papillary and chromophobe renal cell carcinomas as well as oncocytomas and Wilms tumors were analysed for HRPT2 gene alterations. Loss of heterozygosity (LOH) of HRPT2 was found in seven of 56 (12.5%) clear cell, three of 14 (21%) papillary, six of 10 (60%) chromophobe renal cell carcinomas, three of eight (38%) oncocytomas and four of 10 (40%) Wilms tumors. In addition, two novel HRPT2 point mutations, causing K34Q and R292K changes in parafibromin, were detected in one clear cell carcinoma and one Wilms tumor, respectively. These tumors displayed LOH of the remaining wild-type allele, but interestingly no von Hippel–Lindau (VHL) mutation. Functional analysis revealed that the K34Q mutant species of parafibromin is, unlike wild-type protein, defective in suppressing cyclin D1 expression in vivo. Taken together, these results suggest that renal cancer-associated mutations in parafibromin occur in the absence of VHL mutation, which in turn may contribute to constitutively elevated cyclin D1 expression and abnormal cell proliferation.