Wnt1 Promotes Cementum and Alveolar Bone Growth in a Time-Dependent Manner

The WNT/β-catenin signaling pathway plays a central role in the biology of the periodontium, yet the function of specific extracellular WNT ligands remains poorly understood. By using a Wnt1-inducible transgenic mouse model targeting Col1a1-expressing alveolar osteoblasts, odontoblasts, and cementoblasts, we demonstrate that the WNT ligand WNT1 is a strong promoter of cementum and alveolar bone formation in vivo. We induced Wnt1 expression for 1, 3, or 9 wk in Wnt1Tg mice and analyzed them at the age of 6 wk and 12 wk. Micro–computed tomography (CT) analyses of the mandibles revealed a 1.8-fold increased bone volume after 1 and 3 wk of Wnt1 expression and a 3-fold increased bone volume after 9 wk of Wnt1 expression compared to controls. In addition, the alveolar ridges were higher in Wnt1Tg mice as compared to controls. Nondecalcified histology demonstrated increased acellular cementum thickness and cellular cementum volume after 3 and 9 wk of Wnt1 expression. However, 9 wk of Wnt1 expression was also associated with periodontal breakdown and ectopic mineralization of the pulp. The composition of this ectopic matrix was comparable to those of cellular cementum as demonstrated by quantitative backscattered electron imaging and immunohistochemistry for noncollagenous proteins. Our analyses of 52-wk-old mice after 9 wk of Wnt1 expression revealed that Wnt1 expression affects mandibular bone and growing incisors but not molar teeth, indicating that Wnt1 influences only growing tissues. To further investigate the effect of Wnt1 on cementoblasts, we stably transfected the cementoblast cell line (OCCM-30) with a vector expressing Wnt1-HA and performed proliferation as well as differentiation experiments. These experiments demonstrated that Wnt1 promotes proliferation but not differentiation of cementoblasts. Taken together, our findings identify, for the first time, Wnt1 as a critical regulator of alveolar bone and cementum formation, as well as provide important insights for harnessing the WNT signal pathway in regenerative dentistry.

Tendon healing induced by chemically modified mRNAs

Tendon disorders are frequent both in human and veterinary medicine with high re-injury rates and unsatisfactory therapeutic treatments. Application of naked, chemically-modified mRNA (cmRNA), encoding for therapeutic proteins, is an innovative approach to address tendon healing. In the current study, we demonstrated that injection of naked cmRNA, diluted in a glucose-containing solution, into tendons resulted in high protein expression in healthy and experimentally-injured tendons. Injection of bone morphogenetic protein 7 (BMP-7)-encoding cmRNA resulted in a significantly higher expression of BMP-7 protein and reduced formation of collagen type III, compared to vehicle control. Moreover, in a large animal model, reporter protein expression was detectable not only in healthy, but also in experimentally-injured, severely inflamed tendons. Summarising, these results demonstrated the potential of cmRNAs encoding for therapeutic proteins as a new class of drugs for the treatment of tendon disorders.

Effects of vancomycin versus nafcillin in enhancing killing of methicillin-susceptible Staphylococcus aureus causing bacteremia by human cathelicidin LL-37

Recent studies have demonstrated that anti-staphylococcal beta-lactam antibiotics, like nafcillin, render methicillin-resistant Staphylococcus aureus (MRSA) more susceptible to killing by innate host defense peptides (HDPs), such as cathelicidin LL-37. We compared the effects of growth in 1/4 minimum inhibitory concentration (MIC) of nafcillin or vancomycin on the LL-37 killing of 92 methicillin-susceptible S. aureus (MSSA) isolates. For three randomly selected strains among these, we examined the effects of nafcillin, vancomycin, daptomycin, or linezolid on LL-37 killing and autolysis. Growth in the presence of subinhibitory nafcillin significantly enhanced LL-37 killing of MSSA compared to vancomycin and antibiotic-free controls. Nafcillin also reduced MSSA production of the golden staphylococcal pigment staphyloxanthin in 39 % of pigmented strains vs. 14 % for vancomycin. Among the antibiotics tested, only nafcillin resulted in significantly increased MSSA autolysis. These studies point to additional mechanisms of anti-staphylococcal activity of nafcillin beyond direct bactericidal activity, properties that vancomycin and other antibiotic classes do not exhibit. The ability of nafcillin to enhance sensitivity to innate HDPs may contribute to its superior effectiveness against MSSA, as suggested by studies comparing clinical outcomes to vancomycin treatment.

Rsk2, the Kinase Mutated in Coffin-Lowry Syndrome, Controls Cementum Formation

The ribosomal S6 kinase RSK2 is essential for osteoblast function, and inactivating mutations of RSK2 cause osteopenia in humans with Coffin-Lowry syndrome (CLS). Alveolar bone loss and premature tooth exfoliation are also consistently reported symptoms in CLS patients; however, the pathophysiologic mechanisms are unclear. Therefore, aiming to identify the functional relevance of Rsk2 for tooth development, we analyzed Rsk2-deficient mice. Here, we show that Rsk2 is a critical regulator of cementoblast function. Immunohistochemistry, histology, micro-computed tomography imaging, quantitative backscattered electron imaging, and in vitro assays revealed that Rsk2 is activated in cementoblasts and is necessary for proper acellular cementum formation. Cementum hypoplasia that is observed in Rsk2-deficient mice causes detachment and disorganization of the periodontal ligament and was associated with significant alveolar bone loss with age. Moreover, Rsk2-deficient mice display hypomineralization of cellular cementum with accumulation of nonmineralized cementoid. In agreement, treatment of the cementoblast cell line OCCM-30 with a Rsk inhibitor reduces formation of mineralization nodules and decreases the expression of cementum markers. Western blot analyses based on antibodies against Rsk1, Rsk2, and an activated form of the 2 kinases confirmed that Rsk2 is expressed and activated in differentiating OCCM-30 cells. To discriminate between periodontal bone loss and systemic bone loss, we additionally crossed Rsk2-deficient mice with transgenic mice overexpressing the osteoanabolic transcription factor Fra1. Fra1 overexpression clearly increases systemic bone volume in Rsk2-deficient mice but does not protect from alveolar bone loss. Our results indicate that cell autonomous cementum defects are causing early tooth loss in CLS patients. Moreover, we identify Rsk2 as a nonredundant regulator of cementum homeostasis, alveolar bone maintenance, and periodontal health, with all these features being independent of Rsk2 function in systemic bone formation.

Zur Kenntnis einer neuen ternären Phase Cu0,5Nbl1,5O3,7 / About a New Phase Cu0,5Nbl1,5O3,7

Single crystals of Cu0,5Nb1,5O3,7 were prepared and investigated by X-ray methods (a = 376.7, b = 507.3, c = 374,9 pm; β = 101.5°; space group: P21-C2 2). The statistically occupied metal positions (Nb/Cu) have a trigonal prismatic O2- surrounding.

Zur Verbindungsbildung von MeO : M2O3, Teil III Zur Kenntnis von BeGa2O4 / Compound Formation MeO : M2O3, Part III BeGa2O4

A new compound, BeGa2O4, was prepared by high temperature reaction between BeO and Ga2O3. X-ray single crystal investigations show a hitherto unknown structure type of M2+M2 3+O4 compounds. BeGa2O4 crystallizes with hexagonal symmetry a = 775.0 and c = 298.0 pm, space group C2 6h-P63/m. Be2+ and Ga3+ are statistically distributed and are surrounded by O2--tetrahedra

Lysosomal dysfunction causes neurodegeneration in mucolipidosis II 'knock-in' mice

Mucolipidosis II is a neurometabolic lysosomal trafficking disorder of infancy caused by loss of mannose 6-phosphate targeting signals on lysosomal proteins, leading to lysosomal dysfunction and accumulation of non-degraded material. However, the identity of storage material and mechanisms of neurodegeneration in mucolipidosis II are unknown. We have generated 'knock-in' mice with a common mucolipidosis II patient mutation that show growth retardation, progressive brain atrophy, skeletal abnormalities, elevated lysosomal enzyme activities in serum, lysosomal storage in fibroblasts and brain and premature death, closely mimicking the mucolipidosis II disease in humans. The examination of affected mouse brains at different ages by immunohistochemistry, ultrastructural analysis, immunoblotting and mass spectrometric analyses of glycans and anionic lipids revealed that the expression and proteolytic processing of distinct lysosomal proteins such as α-l-fucosidase, β-hexosaminidase, α-mannosidase or Niemann-Pick C2 protein are more significantly impacted by the loss of mannose 6-phosphate residues than enzymes reaching lysosomes independently of this targeting mechanism. As a consequence, fucosylated N-glycans, GM2 and GM3 gangliosides, cholesterol and bis(monoacylglycero)phosphate accumulate progressively in the brain of mucolipidosis II mice. Prominent astrogliosis and the accumulation of organelles and storage material in focally swollen axons were observed in the cerebellum and were accompanied by a loss of Purkinje cells. Moreover, an increased neuronal level of the microtubule-associated protein 1 light chain 3 and the formation of p62-positive neuronal aggregates indicate an impairment of constitutive autophagy in the mucolipidosis II brain. Our findings demonstrate the essential role of mannose 6-phosphate for selected lysosomal proteins to maintain the capability for degradation of sequestered components in lysosomes and autophagolysosomes and prevent neurodegeneration. These lysosomal proteins might be a potential target for a valid therapeutic approach for mucolipidosis II disease.

Popliteal entrapment syndrome and age

On the occasion of diagnosing a popliteal entrapment syndrome in a 59-year old man with no cardiovascular risk factors, who developed acute ischemic leg pain during long distance running, we give an overview on this entity with emphasis on patients' age. The different types of the popliteal artery compression syndrome are summarized. The diagnostic and therapeutic approaches are discussed. The most important clinical sign of a popliteal entrapment syndrome is the lack of atherosclerotic risk factors in patients with limited walking distance. Not only in young athletes but also in patients more than 50 years old the popliteal entrapment syndrome has to be taken into account.

Apoptosis in Bovine viral diarrhea virus (BVDV)-induced mucosal disease lesions: a histological, immunohistological, and virological investigation

Cattle persistently infected with a noncytopathic Bovine viral diarrhea virus (BVDV) are at risk of developing fatal "mucosal disease" (MD). The authors investigated the role of various apoptosis pathways in the pathogenesis of lesions in animals suffering from MD. Therefore, they compared the expression of caspase-3, caspase-8, caspase-9, and Bcl-2L1 (Bcl-x) in tissues of 6 BVDV-free control animals, 7 persistently infected (PI) animals that showed no signs of MD (non-MD PI animals), and 11 animals with MD and correlated the staining with the localization of mucosal lesions. Caspase-3 and -9 staining were markedly stronger in MD cases and were associated with mucosal lesions, even though non-MD PI animals and negative controls also expressed caspase-9. Conversely, caspase-8 was not elevated in any of the animals analyzed. Interestingly, Bcl-x also colocalized with mucosal lesions in the MD cases. However, Bcl-x was similarly expressed in tissues from all 3 groups, and thus, its role in apoptosis needs to be clarified. This study clearly illustrates ex vivo that the activation of the intrinsic, but not the extrinsic, apoptosis pathway is a key element in the pathogenesis of MD lesions observed in cattle persistently infected with BVDV. However, whether direct induction of apoptosis in infected cells or indirect effects induced by the virus are responsible for the lesions observed remains to be established.

Promoting effect of rapeseed proteins and peptides on Sf9 insect cell growth

The Baculovirus Expression Vector System has become widely used for the production of recombinant proteins for research and diagnostics. Serum-free culture media able to support high cell densities have been developed for the large scale culture of insect cells. While serum elimination aims at avoiding the risks associated with the introduction of an ill defined component of bovine origin, additives such as protein hydrolysates from animal sources are still used. An alternative could be the supplementation of culture media with protein hydrolysates derived from plants. In this study, we describe the replacement of lactalbumin hydrolysate with a laboratory produced hydrolysate of rapeseed proteins. Its effect on Sf9 cell growth kinetics, substrate consumption and by-product formation in low-serum or serum-free medium was evaluated. Cells were unable to grow in the presence of a rapeseed protein hydrolysate generated by PTN 3.0 Special((R)) enzyme and containing only 24% of peptides under 1 kDa in size. On the other hand, serum-free medium supplementation with a rapeseed protein hydrolysate obtained with Orientase 90N((R)) enzyme had a strong growth promoting effect, leading to a 60% increase in maximal cell density without affecting cell metabolism. This significant positive effect could be explained by the higher degree of hydrolysis of this digest, with 74% of peptides under 1 kDa in size.

Large-scale production means for the manufacturing of lentiviral vectors

Lentiviral vectors become more and more famous for the use as gene vector for gene therapy purposes for the treatment of acquired or inherited diseases. In this review, the present state of the art of the production of lentiviral vectors is presented with particular emphasis on the large scale production of these vectors for preclinical and clinical purposes. In contrast to oncoretroviral vectors which are produced using stable producer cell lines, clinical grade lentiviral vectors are essentially produced by transient transfection of 293 or 293T cells grown in Cell Factories. The main reason is that these production processes have been developed when good and safe LV producer cell lines were not available. With respect to the purification of lentiviral and in agreement with actual developments in the biotech industry, rather sophisticated downstream processing protocols have been established in order to remove any potentially dangerous process derived contaminant, such as plasmid or host cell DNA or host cell proteins. This review presents large scale production means for LV vectors, the different downstream processing steps as used for the purification of LV vectors as well as LV specific safety issues. Published large scale production and purification processes of lentiviral vectors and their process performances are compared.

Analgesie in der Kolonchirurgie

BACKGROUND

The goal of our study was to evaluate the morphine-sparing effect of nonsteroidal anti-inflammatory drugs (NSAIDs) following both conventional and laparoscopic colon surgery.

MATERIALS AND METHODS

In this prospective, randomized clinical trial, 180 patients were assigned to three groups. Two groups received either paracetamol or parecoxib/valdecoxib in addition to piritramid via patient-controlled or nurse-controlled analgesia pump. Patients in the control group received piritramid only. The total piritramid consumption during hospital stay was recorded.

RESULTS

Total opioid consumption was significantly lower in the two groups who received NSAIDs. Comparing conventional and laparoscopic surgery, the latter group had much lower opioid consumption.

CONCLUSION

The use of NSAIDs following colon surgery significantly reduces postoperative opioid consumption.

In Saccharomyces cerevisiae, impaired PRPP synthesis is accompanied by valproate and Li+ sensitivity

The biosynthetic intermediate PRPP (phosphoribosylpyrophosphate) has a central role in cellular biochemistry since it links carbon and nitrogen metabolism. Its importance may be reflected in the fact that, in the Saccharomyces cerevisiae (yeast) genome, there are five unlinked genes, PRS1-PRS5, each of which is theoretically capable of encoding the enzyme synthesizing PRPP. Interference with the complement of PRS genes in S. cerevisiae has far-reaching consequences for yeast physiology and has uncovered unexpected metabolic links including cell wall integrity and phospholipid metabolism.

[How the bovine viral diarrhea virus outwits the immune system]

The interaction of bovine viral diarrhea virus (BVD virus) with its host has several unique features, most notably the capacity to infect its host either transiently or persistently. The transient infection stimulates an antiviral immune reaction similar to that seen in other transient viral infections. In contrast, being associated with immunotolerance specific for the infecting BVD viral strain, the persistent infection differs fundamentally from other persistent infections like those caused by lentiviruses. Whereas the latter are characterized by complex viral evasion of the host's adaptive immune response by mechanisms such as antigenic drift and interference with presentation of T cell epitopes, BVD virus avoids the immune response altogether by inducing both humoral and cellular immune tolerance. This is made possible by invasion of the fetus at an early stage of development. In addition to adaptive immunity, BVD virus also manipulates key elements of the host's innate immune response. The non-cytopathic biotype of BVD virus, which is capable of persistently infecting its host, fails to induce type I interferon. In addition, persistently infected cells are resistant to the induction of apoptosis by double-stranded RNA and do not produce interferon when treated with this pathogen-associated molecular pattern (PAMP) that signals viral infection. Moreover, when treated with interferon, cells persistently infected with non-cytopathic BVD virus do not clear the virus. Surprisingly, however, despite this lack of effect on persistent infection, interferon readily induces an antiviral state in these cells, as shown by the protection against infection by unrelated viruses. Overall, BVD virus manipulates the host's interferon defense in a manner that optimises its chances of maintaining the persistent infection as well as decreasing the risks that heterologous viral infections may carry for the host. Thus, since not all potential host cells are infected in animals persistently infected with BVD virus, heterologous viruses replicating in cells uninfected with BVD virus will still trigger production of interferon. Interferon produced by such cells will curtail the replication of heterologous viruses only, be that in cells already infected with BVD virus, or in cells in which the heterologous virus may replicate alone. From an evolutionary viewpoint, this strategy clearly enhances the chances of transmission of BVD virus to new hosts, as it attenuates the negative effects that a global immunosuppression would have on the survival of persistently infected animals.

Ramifications of impaired PRPP synthesis in Saccharomyces cerevisiae

The model eukaryote Saccharomyces cerevisiae is well suited to investigate the causes of metabolic disturbance. PRPP [5-phospho-D-ribosyl-1(alpha)-pyrophosphate] may be regarded as a junction of carbon and nitrogen metabolism. As a result of this central position, perturbations in its synthesis can give rise to many unexpected cellular events, such as impaired cell integrity. We have taken advantage of S. cerevisiae's genetic tractability to investigate the metabolic links responsible for connecting the biochemical intermediate PRPP to apparently unrelated cellular functions. This approach provides insight into the co-ordination of different biological processes.

Association between early postoperative coagulation activation and peri-operative myocardial ischaemia in patients undergoing vascular surgery

We investigated the association of peri-operative myocardial ischaemia with activation of coagulation and endogenous fibrinolysis in patients undergoing vascular surgery. In 50 patients, continuous Holter monitoring was performed to assess peri-operative myocardial ischaemia and 12-lead electrocardiography was recorded preoperatively and 72 h postoperatively to assess myocardial infarction. Serial blood samples were drawn peri-operatively to determine the concentrations of fibrin monomers (for activation of coagulation), D-dimer (for endogenous fibrinolysis) and cardiac troponin T and I. Patients with myocardial ischaemia showed higher concentrations of fibrin monomers at 48 h, and higher concentrations of d-dimer preoperatively and at 24 and 48 h postoperatively. In patients with peri-operative myocardial ischaemia, strong positive correlations were observed between fibrin monomer and D-dimer concentrations at 15 min and 4 h postoperatively, and cardiac troponins at 15 min and at 4, 24, 48 and 72 h postoperatively. Early postoperative activation of coagulation and fibrinolysis is associated with peri-operative myocardial cell damage among patients who are at risk for, or have a history of, coronary artery disease plus peri-operative myocardial ischaemia.

Pathogenesis of extrahepatic bile duct atresia (EHBA): comprehension from a surgical point of view

INTRODUCTION

The aim of the study is to establish a complete comprehension of the pathogenesis of Biliary Atresia, and to explain both the variable and redundant pathomorphological, as well as, histological findings.

MATERIALS AND METHODS

The pathomorphological and histological findings in 223 patients with histologically evident EHBA were recorded retrospectively (72 patients) or prospectively (151 patients), according to a projected ascending study. These findings were compared with histological findings in human and rat embryos.

RESULTS

1) The pathomorphological findings recorded in patients with EHBA were also found in stages of normal embryogenesis of the bile duct system in human and rat embryos. 2) Each histological finding in Biliary Atresia corresponds to a finding in an interrupted stage of the normal development in human and rat embryos. 3) The findings in patients and embryos can be explained completely by a disturbed intrinsic epithelium/mesoderm interaction. 4) Some findings in Biliary Atresia cannot be explained easily by the assumption of an extrinsic factor.

CONCLUSION

There is no finding in Biliary Atresia which cannot be completely explained as the result of an intrinsic developmental error, probably due to disturbances or interruption of epithelium/mesoderm interaction during embryogenesis.

Tracheal surgery in children

BACKGROUND

The aim of this study is to show that five distinct types of tracheal anomalies should be differentiated with respect to therapy and prognosis.

METHODS

The records of 12 infants and children seen over a period of 20 years for different tracheal anomalies such as laryngotracheal stenosis (n = 3), long or short-segment stenosis of the upper (n = 2), middle (n = 6), and lower (n = 1) trachea were reviewed. In addition to these 12 patients with congenital stenosis, 3 other patients needed tracheal resections because of oncologic or traumatic disease: in 2, the trachea was infiltrated by a papillary carcinoma of the thyroid gland and in one, the upper part of the trachea was injured by an oral explosion accident. 25 patients presenting during the same period for other tracheal pathologies including esophagotracheal cleft syndrome (n = 7), tracheomalacia (n = 4), total tracheal agenesis (n = 3), or for placement of a tracheostomy (n = 11) due to other diseases were excluded from this study.

RESULTS

There was 1 early death after repair of a laryngotracheal stenosis by cricoid-split and cricoid-splint due to both cerebral hemorrhage and cardiac insufficiency secondary to Fallot's tetralogy. Another child died four weeks after slide tracheoplasty as a result of hypoxic cerebral lesions induced by severe central catheter-related septicemia. One child with therapy-resistant obstructing granulation tissue which developed after a slide tracheoplasty required a tracheostomy. The patient with the tracheal injury died after another accident one year after discharge. All other patients (n = 11) are doing well.

CONCLUSIONS

With respect to therapy of congenital and post-intubation tracheal stenosis, four types should be distinguished. Each of these types requires an adequate surgical procedure. The most important postoperative problem in tracheal surgery is the development of granulation tissue. However, the pathogenesis of granulation is still unknown.

Postoperative 12-lead ECG predicts peri-operative myocardial ischaemia associated with myocardial cell damage

Peri-operative myocardial ischaemia is the single most important risk factor for an adverse cardiac outcome after non-cardiac surgery. The present study examines whether intermittent 12-lead ECG recordings can be used as an early warning tool to identify patients suffering from peri-operative myocardial ischaemia and subsequent myocardial cell damage. Fifty-five vascular surgery patients at risk for or with a history of coronary artery disease were monitored for peri-operative myocardial ischaemia using intermittent 12-lead ECG recordings taken pre-operatively and at 15 min, 20 h, 48 h, 72 h and 84 h postoperatively. The effectiveness of the 12-lead ECG was gauged by examining concordance with continuous 3-channel Holter monitoring and capturing peri-operative myocardial ischaemia by serial analyses of creatine kinase myocardial band isoenzyme and cardiac troponin T and I. The incidence of peri-operative myocardial ischaemia detected by 12-lead ECG was 44% and was identifiable in most patients (88%) 15 min after surgery. The incidence of peri-operative myocardial ischaemia detected by continuous monitoring was 53%, with the most severe episodes occurring intra-operatively and during emergence from anaesthesia. The concordance of the 12-lead method with continuous monitoring was 72%. The concordance of creatine kinase myocardial band isoenzyme activity with the 12-lead method was 71% and with Holter monitoring 57%. The concordance of mass concentration of creatine kinase myocardial band with 12-lead ECG recordings was 75%, and the corresponding value for Holter monitoring was 68%. The concordance of cardiac troponin T and I levels with the 12-lead method was 85% and 87%, respectively, and concordance with Holter monitoring was 72% and 66%, respectively. The postoperative 12-lead ECG identified peri-operative myocardial ischaemia associated with subsequent myocardial cell damage in most patients undergoing vascular surgery.

Replication of primate foamy viruses in natural and experimental hosts

Foamy viruses (FVs) are common apathogenic retroviruses readily spread by horizontal transmission in nonhuman primate and some other mammalian host populations. Primate FV infections have been known for half a century, i.e., 15 years before the definition of retroviruses and another 15 years before the detection of primate immune deficiency viruses. The emerging interest in human retroviruses included primate FV, and although the role of human hosts for FV was greatly overestimated temporarily, enthusiastic researchers compiled invaluable data on molecular biology and classic as well as molecular epidemiology of these viruses. It has been shown that lytic FV infection in a wide range of cell cultures is in great contrast to the silent state of the infection in animals. Once transmitted by saliva via biting, FVs reside in all tissues as DNA copies, but their replication is untraceable except in oral submucosal cells, which are thought to supply the virus for transmission. FVs have not definitely been associated with any disease, regardless of viral phylogenetic differences. Various primate and nonprimate species have been used for studies on the natural carrier state and primary infection. Experimental infections have mostly proven to be inefficient in primates as well as lower laboratory animals. However, investigation of the immune response in FV-infected animals has only partly explained the control of FV replication in the animal host. Thus, the biological role of FV remains an enigma to be resolved in the future.

Human infection with foamy viruses

Virtually all nonhuman primate species investigated thus far including prosimians, New World and Old World monkeys and apes all harbor distinct and species-specific clades of simian foamy virus (SFV). However, evidence supporting the existence of a human-specific foamy virus (FV) is not yet available. Early reports describing widespread infection of healthy and sick humans with FV could not be confirmed. In contrast, all FV infections documented in humans are of zoonotic origin and are identified in persons occupationally exposed to nonhuman primates. The introduction of SFV into humans raises several public health questions regarding disease outcomes and potential for human-to-human transmissibility. The available data from a very limited number of SFV-infected humans suggest that these infections are nonpathogenic and are not easily transmissible. Additional studies are needed to better define the prevalence and natural history of SFV in humans.

Transcription factors acting on the promoter of the rat fatty acid synthase gene

Fatty acid synthase (FAS), one of the main lipogenic enzymes, converts dietary calories into a storage form of energy. The transcription factors, stimulatory proteins 1 and 3 (Sp1 and Sp3), nuclear factor Y (NF-Y), upstream stimulatory factor (USF) and sterol regulatory element binding protein-1 (SREBP-1) have cognate binding sites on the promoter of the FAS gene. It was shown that Sp1 and NF-Y interact co-operatively at the diet-induced DNase I-hypersensitive site at position -500. Adjacent binding sites for NF-Y and Sp1 have also been found between -71 and -52, and -91 and -83. cAMP regulation is mediated via the inverted CAAT element (ICE) at -99 to -92, which binds NF-Y. The FAS insulin-responsive element 3 (FIRE3)-binding site at -71 to -52 is capable of binding NF-Y, USF and SREBP-1, and is required for the sterol response in conjunction with the co-activator NF-Y around -100. Surprisingly, both FIRE3 and ICE are also necessary for the response to retinoic acid that plays a role in development and is an essential component of the diet.

Peroxovanadate inhibits Ca2+ release from mitochondria

Mitochondria contain a specific Ca2+ release pathway which operates when oxidized mitochondrial pyridine nucleotides are hydrolyzed. NAD+ hydrolysis and therefore Ca2+ release is possible when some vicinal thiols are cross-linked. Here we report that the thiol oxidant peroxovanadate inhibits the specific Ca2+ release pathway. In mitochondria, peroxovanadate causes a complete loss of reduced glutathione, which is not accompanied by formation of glutathione disulfide, and a partial loss of protein thiols. In model reactions, peroxovanadate oxidizes reduced glutathione predominantly to the sulfonate derivative, but does not react with glutathione disulfide. When the vicinal thiols relevant for Ca2+ release are cross-linked, Ca2+ release is no longer inhibited by peroxovanadate. Conversely, pretreatment of mitochondria with peroxovanadate makes them insensitive to compounds promoting the disulfide state. These results suggest that peroxovanadate inhibits the prooxidant-induced Ca2+ release from mitochondria by (i) depleting mitochondria of reduced glutathione and (ii) oxidizing the vicinal thiols relevant for Ca2+ release to a state higher than disulfide, presumably the sulfonate state. The findings provide further insight into the regulation of Ca2+ release from intact mitochondria, and may be relevant for a better understanding of the action of peroxovanadate in cells, where the compound can be insulin mimetic.

A novel lentivirus vector derived from apathogenic simian immunodeficiency virus

The improvement of gene transfer efficiency in growth-arrested cells using human immunodeficiency virus type 1 (HIV-1)-derived vectors led to the development of vectors derived from other members of the lentivirus family. Here we report the generation of a lentiviral vector derived from the apathogenic molecular virus clone SIVagm3mc of the simian immunodeficiency virus from African green monkeys (Cercocebus pygerythrus). Upon pseudotyping with the G-protein of vesicular stomatitis virus (VSV-G), the SIVagm-derived vector was shown to transduce proliferating and growth-arrested mammalian cell lines, including human cells. After in vivo inoculation into the striatum of the adult rat brain, the vector was shown to transduce terminally differentiated neurons and oligodendrocytes as well as quiescent and reactive astrocytes. Moreover, SIVagm transfer vector mRNA was efficiently packaged by HIV-1 vector particles. Homologous [SIV(SIV)] vectors generated by using the SIVagm-derived envelope glycoproteins allowed selective gene transfer into human CD4(+)/CCR5(+) cells. Thus, the SIVagm3mc-derived vector is a useful alternative to HIV-1-derived lentiviral vectors in somatic gene therapy.

Toward an understanding of the furoxan-dinitrosoethylene equilibrium

The tautomerism of furoxan (1,2,5-oxadiazole-2-oxide) has been investigated by different computational methods comprising modern density functionals as well as single-reference and multi-reference ab initio methods. The ring-opening process to 1,2-dinitrosoethylene is the most critical step of the reaction and cannot be treated reliably by low-level computations. The existence of cis-cis-trans-1,2-dinitrosoethylene as a stable intermediate is advocated by perturbational methods, but high-level coupled-cluster calculations identify this as an artifact. In contrast to the analogous reaction in benzofuroxans, cis-cis-cis-1,2-dinitrosoethylene was found to be a transition state rather than a local minimum. Model potentials were used to explain the occurrence and the disappearing of transition states and local minima relative to the reaction of benzofuroxan. Low-lying triplet states that can be accessed due to spin-orbit coupling were investigated as taking part in alternative routes to a proposed singlet pathway. Barriers for rotations of the nitroso groups on the S(0) and T(1) surfaces are reported.

The FIRE3-mediated sterol response of the FAS promoter requires NF-Y/CBF as a coactivator

The transcription of the fatty acid synthase (FAS) gene is regulated by the sterol status of the cell via cleavage of the sterol regulatory element-binding protein (SREBP). When human HepG2 hepatoma cells were cotransfected with an expression plasmid for mature SREBP-1a together with FAS promoter/reporter constructs significant increases in reporter activity were observed. Deletion analysis of the FAS promoter between -151 and -52 relative to the transcription start site pinpoint two cis-elements important in sterol regulation of the FAS gene. One element, FIRE3, between -71 and -52 can bind in vitro translated and transcribed SREBP-1a whereas the other element, the inverted CCAAT element ICE(-97/-92), binds the trimeric transcription factor NF-Y/CBF as shown with rat liver extract and reconstituted, recombinant NF-Y. The results clearly show that the coactivator for SREBP-1a in this cell line is NF-Y. This finding was confirmed by using a dominant negative form of NF-YA, NF-YAm29, which interferes with the effect of ectopically expressed SREBP-1a on FAS reporter activity.

Semicircular papillotomy: a new surgical technique for removal of bile stones lodged in the ampulla of Vater

Bile stones lodged in the ampulla of Vater present a rare but often difficult problem. Considering the disadvantages of conventional papillotomy and papillectomy, we developed a technique in which both the anatomic structures and their function are preserved. Histologic studies of the ampulla provided the basis for the technique, in which the muscular layers of the ampulla are not cut through as in conventional papillotomy but are bluntly separated, preserving this important anatomic component of the ampulla saved. The postoperative and long-term outcome of seven patients with bile stones lodged in the ampulla are reported. We found semicircular lateral papillotomy a safe procedure that preserves the muscular structures and function of the ampulla.

Running-buffer composition influences DNA-protein and protein-protein complexes detected by electrophoretic mobility-shift assay (EMSA)

The gel-shift assay is a rapid, extremely sensitive, technically simple and widely used method for investigating nucleic acid-protein interaction based on the observation that binding of protein to DNA or RNA fragments usually leads to a reduction in the electrophoretic mobility of the fragment in non-denaturing gels. Here we report on the critical role of the running buffer and show that its importance ranks equally with other factors affecting complex formation and stability such as binding buffer, temperature, non-specific competitor or gel concentration and/or composition. We demonstrate differences in the binding patterns obtained with oligonucleotides containing binding sites for the ubiquitously expressed transcription factors Sp1 (stimulatory protein 1), NF-Y (nuclear factor Y) and USF (upstream stimulatory protein), which are dependent on the ionic strength of the running buffer used. Furthermore, we show the influence of glycine concentration on Sp1 binding using recombinant glutathione S-transferase-Sp1 fusion protein expressed in Escherichia coli.

Noncytopathic bovine viral diarrhea virus inhibits double-stranded RNA-induced apoptosis and interferon synthesis

Bovine viral diarrhea virus (BVDV), a pestivirus of the Flaviviridae family, is an economically important cattle pathogen with a worldwide distribution. Both noncytopathic (ncp) and cytopathic (cp) biotypes of BVDV can be isolated from persistently infected cattle suffering from the lethal mucosal disease. The cp biotype correlates with the production of the NS3 nonstructural protein, which in the corresponding ncp biotype is present in its uncleaved form, NS23. Previously, we have shown that cp but not ncp BVDV induces the formation of alpha/beta interferons in bovine macrophages. In this study, we demonstrate that ncp BVDV inhibits the induction of apoptosis and the expression of interferon alpha/beta by poly(IC), a synthetic double-stranded RNA (dsRNA). Inhibition was observed only in cells which had been infected with ncp BVDV at least 12 h prior to the addition of dsRNA, which indicates that expression of viral proteins is necessary for the ncp virus to inhibit the effects of poly(IC). Additional experiments using transfected poly(IC) showed that ncp BVDV interfered with the intracellular action of dsRNA rather than with its uptake into the cells. Infected cells were not resistant to induction of apoptosis by actinomycin D or staurosporine, which suggests that ncp BVDV may specifically interfere with signaling through dsRNA. Interference with the innate antiviral host responses may explain the successful establishment of persistent infection by ncp BVDV in fetuses early in their development.