Myocarditis in newborn wild-type BALB/c mice infected with the murine gamma herpesvirus MHV-68

OBJECTIVES: Animal models of human Epstein-Barr virus (EBV) infection include EBV infection of primates and infection of mice with MHV-68, a further gamma herpesvirus (gamma-HV). We aimed at extending the MHV-68 model to study gamma-HV-related cardiac disease. METHODS: Newborn wild-type BALB/c- (n=107), wild-type C57BL/6- (n=17) and immunodeficient B6-(Rag1) mice (n=18) were infected by nasal inoculation and evaluated for histopathological changes as well as tissue viral loads. RESULTS: From day 5 on BALB/c mice showed myocardial viral replication. Whereas focal inflammation occurred simultaneously, necrosis was first observed 9 days post-infection. The maximum rates of necrosis (40%) and of focal inflammation (33%) were found after 10 to 12 and 33 to 35 days, respectively. Some animals developed persistent viral activity and inflammation throughout the observation period of three months. Inflammation was mainly related to T cell infiltrates. Although C57BL/6 mice also showed myocardial inflammation, necrosis was not found suggesting differences in the susceptibility to the virus in distinct mouse strains. In immunodeficient animals higher myocardial viral loads were observed compared to wild-type mice but no cardiac lesions, which suggests that the antiviral immune response contributed to the lesions. CONCLUSIONS: The model system presented here is the first to allow detailed studies on cardiac disease caused by gamma-HV infections and may facilitate the development of more specific treatment options for human cardiac EBV infection.     

Neuroimaging for the anesthesiologist

Neuroimaging is essential in the treatment of cerebral nervous system disorders or in patients in the ICU with deterioration of their neurologic function. Leading clinical symptoms are acute neurologic deficits with different stages of hemisymptomatology, primary or progressing loss of consciousness or vigilance deficit, focal or generalized seizures, sometimes combined with an acute respiratory or circulatory insufficiency. The resulting questions can be summarized in those of intracranial space occupying hemorrhage; acute infarction; and signs for reduced cerebral blood flow, cerebrovascular vasospasm, or intracranial mass. Recent evolutions in imaging have contributed to an increase in diagnostic sensitivity and specificity along with reduced side effects. This article illustrates typical and atypical differential diagnoses, with some emphasis on traumatic brain injury.     

Transgene expression by oncolytic adenoviruses is modulated by E1B19K deletion in a cell type-dependent manner

Major strategies to increase oncolytic adenovirus efficacy, as required for clinical applications, are enhancing oncolysis by acceleration of virus release/spread and “arming” by insertion of therapeutic genes. We investigated whether these strategies can be effectively combined as it has been speculated that the arming approach rather benefits from delayed cell lysis and extended time for protein synthesis. We report that deleting adenoviral E1B19K results in an apoptosis-dependent early viral release and thus enhanced oncolysis in several tumor cells, but inhibits virus replication in others. In the former case, apoptosis induction and early cell lysis did not interfere with late transgene expression. Thus, transgene expression was dramatically increased over time due to better virus spread. In A549 cells, transgene expression by the E1B19K⁻ virus at 5 days post-infection was higher than for the E1B19K⁺ virus at 10 days. These properties may be of critical importance in patients, where time for virus spread is limited.     

The influence of 5-aminosalicylic acid on the progression of colorectal adenomas via the β-catenin signaling pathway

Surveillance colonoscopy is an important strategy for prevention of colorectal cancer. 5-aminosalicylate (ASA) (mesalazine) is discussed as a chemopreventive agent as it reduces the cancer risk in ulcerative colitis patients. The current study analyses the effect of 5-ASA on Wnt/β-catenin signaling in vitro and in vivo in colon epithelial cells. The effect of 5-ASA was determined using a β-catenin/T-cell factor (TCF)-reporter assay and by western blotting in cultured colon cancer cells. Formalin fixed paraffin embedded material from 227 polyps removed from a subgroup of 56 patients, who participated in a randomized placebo-controlled 3-year prevention trial with 5-ASA was evaluated according to histomorphological characteristics and expression of β-catenin and target genes Cox2, cyclin D1 and E-cadherin as well as ornithine decarboxylase (ODC). Patients were grouped into a low-risk and a high-risk group according to the number of adenomas at initial colonoscopy. ?-catenin/TCF signaling activity was significantly reduced by 5-ASA treatment possibly through a reduction in ?-catenin levels. Moreover, 5-ASA significantly reduced ?-catenin levels and nuclear localization in patients' adenomas. In addition, 5-ASA also significantly changed expression of the downstream targets Cox2, cyclin D1 and E-cadherin, correlating with ?-catenin status. Moreover, 5-ASA significantly reduced levels of ODC in vivo. Expression of p53 was unaltered by the 5-ASA treatment. Our study shows a significant in vitro and long-term in vivo effect of 5-ASA on ?-catenin signaling as a key signaling pathway in the development of colorectal adenoma. Therefore, we suggest the use of 5-ASA as a promising drug for prevention of sporadic colorectal carcinoma.     

Molecular analysis of Helicobacter pylori-associated gastric inflammation in naïve versus previously immunized mice

To identify mechanisms of immunity against Helicobacter pylori, we performed microarray analysis on gastric tissue from infected mice and mice vaccinated prior to challenge. RNA from gastric tissue was used to screen over 10,000 genes. MHC antigens and GTP binding proteins were upregulated in both groups. Infected mice were characterized by expression of innate host defense markers while immune mice expressed many IFN-gamma response genes and T cell markers. Results were confirmed for several genes by RT-PCR. CD4+ spleen cells from immune mice produced significantly more IFN-gamma than from infected mice. These results support a role for T cell regulated inflammation in H. pylori immunity.     

Noncontact optical measurement of lens capsule thickness in human, monkey, and rabbit postmortem eyes

PURPOSE: To measure interspecies thickness differences in the central anterior and posterior capsules of postmortem crystalline lenses, by a technique that maintains the anatomic integrity of the lens. METHODS: Central capsule thickness was measured with a custom-built, noncontact optical system, using a focus detection technique. Anterior and posterior lens capsule thickness measurements were performed on 22 human, 29 monkey, and 34 New Zealand White rabbit intact postmortem lenses in situ. Eyes were prepared for optical measurements by bonding a PMMA ring to the sclera in the region of the ciliary body after the conjunctiva, adipose, and muscle tissues were removed. The posterior pole was removed by making a circumferential incision through the sclera approximately 7 mm posterior to the limbus. Excess vitreous was removed to expose the posterior capsule surface, and the eye assembly was placed on a Teflon slide. The cornea and iris were sectioned to expose the anterior capsule surface. After the experiments, the lenses were excised, placed in 10% buffered formalin, and prepared for histology. Lens capsule thickness was measured from the histologic slides and compared to the optical RESULTS: results. Central anterior lens capsule thickness was 8.2 +/- 5.5 (human), 7.5 +/- 4.4 (monkey), and 10.7 +/- 4.2 (rabbit) microm optically and 12.4 +/- 2.5 (human), 10.7 +/- 3.7 (monkey), and 10.4 +/- 2.0 (rabbit) microm histologically. Central posterior capsule thickness was 6.3 +/- 2.2 (human), 5.9 +/- 1.7 (monkey), and 7.8 +/- 2.3 (rabbit) microm optically and 4.1 +/- 1.5 (human), 3.5 +/- 1.6 (monkey), and 4.7 +/- 2.5 (rabbit) microm histologically. CONCLUSIONS: The central anterior and posterior lens capsule thicknesses do not appear to vary considerably among human, rabbit, and monkey eyes. There were significant differences between optical in situ measurements and histology, which indicates that histologic preparation may affect lens capsule thickness.     

Detection of the human organic anion transporters SLC21A6 (OATP2) and SLC21A8 (OATP8) in liver and hepatocellular carcinoma

Transport proteins mediating the selective uptake of organic anions into human hepatocytes include the organic anion transporters SLC21A6 (also termed OATP2, OATP-C, or LST-1) and SLC21A8 (OATP8). Both transporters are localized to the basolateral membrane of human hepatocytes. Because of the importance of these transporters for hepatobiliary elimination, including the removal of bilirubin and its conjugates from the blood circulation, we have generated monoclonal antibodies for studies on the expression and localization of these transport proteins. We describe two antibodies, designated monoclonal antibody MDQ (mMDQ) and monoclonal antibody ESL (mESL), directed against the amino terminus and the carboxyl terminus of human SLC21A6, respectively. Both antibodies have been characterized by immunoblot analysis, immunoprecipitation, and immunofluorescence microscopy. While mESL reacted specifically with SLC21A6, mMDQ detects both SLC21A6 and SLC21A8. Neither of the two antibodies reacted with other human, or with dog, rat, or mouse liver SLC21A family members. Antibody mMDQ may be used for the simultaneous detection of SLC21A6 and SLC21A8 in immunoblotting because of its immunoreactivity with both molecules and because of the different molecular masses of both glycosylated proteins in human hepatocytes. This is exemplified in hepatocellular carcinomas where SLC21A6 and SLC21A8 were differentially synthesized and showed an irregular staining pattern. Both transport proteins have not been detected in human hepatoma HepG2 cells. In routine paraffin sections, 10 of 12 hepatocellular carcinomas were focally positive with antibody mMDQ. In contrast, cholangiocarcinomas and liver metastases of colorectal and pancreatic adenocarcinoma were negative without exception. This suggests the usefulness of SLC21A6/SLC21A8 within a panel of tumor markers for hepatocellular carcinomas. Moreover, both antibodies should be useful in studies on the expression and localization of two important uptake transporters of human hepatocytes under physiologic and pathophysiologic conditions.     

Evaluation of treatment options for postoperative and spontaneous chylothorax in adults

Open in a separate window OBJECTIVESBoth postoperative and spontaneous chylothorax remain therapeutic challenges without recommendations for a standardized treatment approach. Regardless of its aetiology, patients with chylothorax experience prolonged hospitalization and suffer from the associated complications or the invasive therapy administered.METHODSWe conducted a retrospective, observational review of adult patients with chylothorax treated between January 2010 and September 2019. The primary end point was successful management with sustained cessation and/or controlled chylous output. Therapy duration, inpatient stay and the incidence of complications were evaluated as secondary end points.RESULTSOf the 36 patients included (22 men; median age 63 years), 24 patients (67%) suffered from a postoperative accumulation of chylous fluid in the pleural space; in the remaining 12 (33%) patients, chylothoraces occurred spontaneously. Initial conservative treatment was successful in 42% (n = 15); in the other 20 cases (56%) additional invasive therapeutic strategies were followed. A complicated course requiring more than 1 treatment was seen in 54% (n = 13) of the postoperative and in 58% (n = 7) of the spontaneous cases. The median length of hospitalization was significantly longer in the postoperative group (37.5 vs 15.5 days; P = 0.016). Serious complications were observed only in the postoperative group (P = 0.28). There were no in-hospital deaths.CONCLUSIONSBasic treatment of both postoperative and spontaneous chylothorax should include dietary measures in all patients. Additional sclerosing radiotherapy and interventional or surgical therapy are often necessary. The choice of therapeutic approach should be indicated, depending on the aetiology and development of the chylothorax. Early, multimodal treatment is recommended.