bluuebunny/crossref_metadata_2025 huggingface dataset:
Down‐regulation of cardiac lineage protein (CLP‐1) expression in CLP‐1 +/− mice affords cardioprotection against ischaemic stress
Authors: Mascareno Eduardo , Manukyan Irena , Das Dipak K. , Siddiqui M. A. Q.
Published: July 2008

In order to understand the transcriptional mechanism that underlies cell protection to stress, we evaluated the role of CLP‐1, a known inhibitor of the transcription elongation complex (pTEFb), in CLP‐1 +/− mice hearts. Using the isolated heart model, we observed that the CLP‐1+/− hearts, when subjected to ischaemic stress and evaluated by haemodynamic measurements, exhibit significant cardioprotection. CLP‐1 remains associated with the pTEFb complex in the heterozygous hearts, where as it is released in the wild‐type hearts suggesting the involvement of pTEFb regulation in cell protection. There was a decrease in Cdk7 and Cdk9 kinase activity and consequently in phosphorylation of serine‐5 and serine‐2 of Pol II CTD in CLP‐1 +/− hearts. However, the levels of mitochondrial proteins, PGC‐1α and HIF‐1α, which enhance mitochondrial activity and are implicated in cell survival, were increased in CLP‐1+/− hearts subjected to ischaemic stress compared to that in wild‐type CLP‐1+/+ hearts treated identically. There was also an increase in the expression of pyruvate dehydrogenase kinase (PDK‐1), which facilitates cell adaptation to hypoxic stress. Taken together, our data suggest that regulation of the CLP‐1 levels is critical to cellular adaptation of the survival program that protects cardiomyocytes against stress due collectively to a decrease in RNA Pol II phosphorylation but an increase in expression of target proteins that regulate mitochondrial function and metabolic adaptation to stress.
Evaluation of blood vessel ingrowth in fibrin gel subject to type and concentration of growth factors
Authors: Arkudas A. , Tjiawi J. , Saumweber A. , Beier J. P. , Polykandriotis E. , Bleiziffer O. , Horch R. E. , Kneser U.
Published: July 2008

Our aim was to quantitatively assess the angiogenetic effects of VEGF and bFGF immobilized in a fibrin‐based drug delivery system in a suitable subcutaneous rat model. After evaluation of a suitable implantation technique (6 rats), four teflon isolation chambers containing fibrin gel matrices were implanted subcutaneously in an upside‐down fashion on the back of 30 Lewis rats. The matrices consisted of 500 μl fibrin gel with two different fibrinogen concentrations (10 mg/ml or 40 mg/ml fibrinogen) and 2 I.U./ml thrombin and contained VEGF and bFGF in five different concentrations (0 to 250 ng/ml each). At 3, 7 and 14 days after implantation, matrices were explanted and subjected to histological and morphometrical analysis. At 1 week, the volume of the fibrin clots was significantly smaller in the 100 and 250 ng/ml VEGF and bFGF groups in comparison to lower concentrated growth factors. At 1 and 2 weeks, the use of growth factors in low concentrations (25 ng/ml VEGF and bFGF) significantly increased the amount of fibrovascular tissue, average fraction of blood vessels and number of blood vessels at the matrix–host interface in comparison to growth factor‐free controls. Higher concentrations were neither associated with further increase of tissue formation nor with increased sprouting of blood vessels in this model. This study demonstrates that fibrin gel‐immobilized angioinductive growth factors efficiently stimulate generation of fibrovascular tissue and sprouting of blood vessels in a newly developed subcutaneous upside‐down isolation chamber model with an optimum between 25 and 100 ng/ml.
Paraoxonase 1 activities and polymorphisms in autism spectrum disorders
Authors: Paşca Sergiu P. , Dronca Eleonora , Nemeş Bogdan , Kaucsár Tamás , Endreffy Emõke , Iftene Felicia , Benga Ileana , Cornean Rodica , Dronca Maria
Published: July 2008

Autism spectrum disorders (ASD) comprise a complex and heterogeneous group of conditions of unknown aetiology, characterized by significant disturbances in social, communicative and behavioural functioning. Recent studies suggested a possible implication of the high‐density lipoprotein associated esterase/lactonase paraoxonase 1 (PON1) in ASD. In the present study, we aimed at investigating the PON1 status in a group of 50 children with ASD as compared to healthy age and sex matched control participants. We evaluated PON1 bioavailability (i.e.arylesterase activity) and catalytic activity (i.e.paraoxonase activity) in plasma using spectrophotometric methods and the two common polymorphisms in thePON1coding region (Q192R, L55M) by employing Light Cycler real‐time PCR. We found that both PON1 arylesterase and PON1 paraoxonase activities were decreased in autistic patients (respectively,P< 0.001,P< 0.05), but no association with less active variants of thePON1gene was found. The PON1 phenotype, inferred from the two‐dimensional enzyme analysis, had a similar distribution in the ASD group and the control group. In conclusion, both the bioavailability and the catalytic activity of PON1 are impaired in ASD, despite no association with the Q192R and L55M polymorphisms in thePON1gene and a normal distribution of the PON1 phenotype.
A pro‐inflammatory signature mediates FGF2‐induced angiogenesis
Authors: Andrés Germán , Leali Daria , Mitola Stefania , Coltrini Daniela , Camozzi Maura , Corsini Michela , Belleri Mirella , Hirsch Emilio , Schwendener Reto A. , Christofori Gerhard , Alcamì Antonio , Presta Marco
Published: July 2008

Fibroblast growth factor‐2 (FGF2) is a potent angiogenic growth factor. Here, gene expression profiling of FGF2‐stimulated microvascular endothelial cells revealed, together with a prominent pro‐angiogenic profile, a pro‐inflammatory signature characterized by the up‐regulation of pro‐inflammatory cytokine/chemokines and their receptors, endothelial cell adhesion molecules and members of the eicosanoid pathway. Real‐time quantitative PCR demonstrated early induction of most of the FGF2‐induced, inflammation‐related genes. Accordingly, chick embryo chorioallantoic membrane (CAM) and murine Matrigel plug angiogenesis assays demonstrated a significant monocyte/macrophage infiltrate in the areas of FGF2‐driven neovascularization. Similar results were obtained when the conditioned medium (CM) of FGF2‐stimulated endothelial cells was delivered onto the CAM, suggesting that FGF2‐upregulated chemoattractants mediate the inflammatory response. Importantly, FGF2‐triggered new blood vessel formation was significantly reduced in phosphatidylinositol 3‐kinase‐γ null mice exhibiting defective leucocyte migration or in clodronate liposome‐treated, macrophage‐depleted mice. Furthermore, the viral pan‐chemokine antagonist M3 inhibited the angiogenic and inflammatory responses induced by the CM of FGF2‐stimulated endothelial cells and impaired FGF2‐driven neovascularization in the CAM assay. These findings point to inflammatory chemokines as early mediators of FGF2‐driven angiogenesis and indicate a non‐redundant role for inflammatory cells in the neovascularization process elicited by the growth factor.
In vivo engineering of a human vasculature for bone tissue engineering applications
Authors: Steffens Lilian , Wenger Andreas , Stark G. Björn , Finkenzeller Günter
Published: July 2008

The neovascularization of three‐dimensional voluminous tissues, such as bone, represents an important challenge in tissue engineering applications. The formation of a preformed vascular plexus could maintain cell viability and promote vascularization after transplantation. We have developed a three‐dimensional spheroidal coculture system consisting of human primary endothelial cells and human primary osteoblasts (hOBs) to improve angiogenesis in bone tissue engineering applications. In this study, we investigated the survival and vascularization of the engineered implants in vivo. Endothelial cell spheroids were cocultured with hOBs in fibrin and seeded into scaffolds consisting of processed bovine cancellous bone (PBCB). The cell‐seeded scaffolds were evaluated for their angiogenic potential in two different in vivo assays: the chick embryo chorioallantoic membrane (CAM) model and the severe combined immunodeficiency disorder (SCID) mouse model. In both assays, the development of a complex three‐dimensional network of perfused human neovessels could be detected. After subcutaneous implantation into immunodeficient mice, the newly formed human vasculature was stabilized by the recruitment of murine smooth muscle α‐actin‐positive mural cells and anastomoses with the mouse vasculature. We conclude that this endothelial cell spheroid system can be used to create a network of functional perfused blood vessels in vivo. The finding that this process takes place with high efficacy in the presence of co‐implanted primary osteoblasts and in an osteoconductive environment provided by the PBCB scaffold, suggests that this system may be suitable for improving vascularization in bone tissue engineering.
The cleavage of thyroid‐stimulating hormone receptor is dependent on cell–cell contacts and regulates the hormonal stimulation of phospholipase c
Authors: Hai Mai‐Thu Vu , Radu Aurelian , Ghinea Nicolae
Published: July 2008

Thyroid‐stimulating hormone receptor (TSHR) consists of a hormone‐binding extracellular subunit and a seven‐transmembrane spanning subunit that interacts with the G proteins Gαs and Gαq. The two subunits, generated by proteolytic cleavage of a single polypeptide chain, are held together by disulphide bridges. The receptor is completely cleaved in thyroid tissue, while in cultured cells (thyrocytes and non‐thyroid cells) the cleaved and uncleaved forms coexist. The reasons for these divergent data are not understood. Here we provide an explanation by showing that cleavage depends on cell–cell contacts. An almost complete cleavage was observed in confluent cells, while in sparse cells most of the receptor was in the uncleaved form. We also show that coupling of TSHR to Gαq (as measured by inositolphosphate generation) is markedly reduced when the receptor is not cleaved. In contrast, coupling to Gαs [as measured by cyclic adenosine 3′,5′‐monophosphate (cAMP) synthesis] is unaffected by cleavage of the receptor. These results suggest that the cell–cell contacts are necessary for cleavage of the receptor, which acts as a regulatory step in inositolphosphate production via phospholipase C activation. The latter observation was confirmed using cells that express the uncleavable mutant TSHR‐Δ50‐NET, for which the TSH‐stimulated inositolphosphate production was completely abolished.
Orthodontic extraction of mandibular third molar to avoid nerve injury and promote periodontal healing
Authors: Alessandri Bonetti Giulio , Incerti Parenti Serena , Checchi Luigi
Published: July 2008

Aim: Impacted mandibular third molar extraction is a common procedure in oral surgery, not without risk of nerve injury and periodontal defects on the distal aspect of the adjacent second molar. The “orthodontic extraction” is proposed as a method to avoid mandibular nerve injury during the extraction of a deeply embedded third molar and to prevent or limit such periodontal problems.

Material and Methods: A 28‐year‐old man presented a deeply impacted left mandibular third molar that required extraction. Radiographs revealed a very slight quantity of bone at the distal surface of the adjacent second molar. The third molar was extruded according to the “orthodontic extraction” technique. A 3‐month retention phase elapsed to ensure adequate bone maturation and the tooth was finally extracted.

Results: No neurological complications occurred. A minimal residual bone defect at the distal surface of the adjacent second molar was detected radiographically both post‐operatively and at the 3‐year follow‐up.

Conclusions: Orthodontic extraction makes third molar removal easier and has no neurological risk. This procedure, followed by a 3‐month retention phase, appears to be effective in preventing or limiting the development of periodontal problems on the distal aspect of the adjacent second molar.
Granuloma annulare – a manifestation of infection with Borrelia?
Authors: Ziemer Mirjana , Grabner Tanja , Eisendle Klaus , Baltaci Mehmet , Zelger Bernhard
Published: July 2008

Background:  Among the theories of origin of granuloma annulare (GA) are those of infection. Reports gave raise to the assumption that there is evidence for Borrelia as the causing agent.

Methods:  To assess the evidence for infection with Borrelia in GA, tissue sections were stained with a polyclonal Borrelia antibody. With focus‐floating microscopy (FFM), slides were scanned at a 200‐ to 400‐fold magnification. Part of the material was also investigated with a Borrelia‐specific polymerase chain reaction (PCR).

Results:  A total of 157 biopsies of GA have been investigated. Using FFM, Borrelia were detected in 127 cases of GA (80.9%). Borrelia were more prominent in localized (85.2%) than in diffuse GA (62.1%). In 27 cases of GA analysed by PCR, Borrelia‐specific DNA could be detected in only one case (3.7%), but was positive in 21 cases by FFM (77.8%). About 93.3% of 15 control cases of borreliosis were positive with FFM and 46.7% with PCR, while all controls other than borreliosis remained negative for spirochetes.

Conclusion:  FFM is a reliable method to show Borrelia in tissue sections of GA, which is more sensitive than PCR. This underlines the possibility that Borrelia are involved specifically in the aetiology and pathogenesis of GA.
Evaluation of skin biopsies for fungal infections: role of routine fungal staining
Authors: Mohan Harsh , Bal Amanjit , Aulakh Rakhi
Published: July 2008

Background:  The diagnosis of cutaneous fungal infection is usually made on clinical examination of the lesion and direct microscopic examination of skin scrapings with potassium hydroxide. Histopathological examination is rarely required to confirm dermatophytic infections. There is often a discord between the clinical and histopathological findings and many times clinical appearance can have a poor histopathological correlation.

Methods:  This retrospective study was carried out on all skin biopsies received in a period of 1 year. The clinical details of all cases were retrieved and slides were reviewed. Routine fungal staining periodic acid‐Schiff (PAS) stain was performed in all cases.

Results:  Of 403 skin biopsies received in 1 year, material for further staining was available in 338. On re‐examining the slides stained with PAS stain, fungi were identified in 34 cases (10%), of which fungal infection had been suspected clinically in five cases.

Conclusions:  Use of routine stains like PAS can help to reach a correct diagnosis and initiate appropriate treatment. Fungal staining should be done in skin biopsies with non‐specific clinical details and microscopic findings for best patient management.
Androgen receptor overexpression in Becker nevus: histopathologic and immunohistochemical analysis
Authors: Kim Young Jin , Han Jae Ho , Kang Hee Young , Lee Eun‐So , Kim You Chan
Published: July 2008

Background:  Becker nevus (BN) is a unilateral, hairy, pigmented cutaneous hamartoma that frequently appears in adolescence. Several features of BN suggest that increased androgen sensitivity plays a role in its pathogenesis. There have been only a few studies of histopathologic and immunohistochemical characteristics of BN, and the etiopathogenesis has not been fully established.

Methods:  Two‐millimeter punch biopsies were taken from lesional and perilesional normal skin of 30 patients diagnosed as having BN. Fifteen skin samples each of lentigo and café au lait spots were used as controls. The sections were stained with hematoxylin‐eosin, Fontana‐Masson, antibodies to NKI/beteb, MART‐1 (Melanoma Antigen Recognized by T cells), S‐100 protein and androgen receptor (AR).

Results:  Histopathologic features of BN showed frequent acanthosis, papillomatosis, keratotic plugging, irregular rete ridge elongation and flattening in the epidermis. Especially, the shape of the rete ridges in BN had a relatively characteristic appearance, which was the fusion of more than two adjacent rete ridges. Melanocyte counts were significantly increased in BN skin. The extent of AR expression was significantly higher in the epidermis of BN.

Conclusions:  Our study indicates that there may be an association between AR and BN, but additional studies will be required to evaluate this further.
Comparison of CD23 staining patterns in Merkel cell carcinoma and non‐cutaneous small cell carcinoma
Authors: Carvalho Jason , Fullen Douglas , Lowe Lori , Su Lyndon , Ma Linglei
Published: July 2008

Background:  During our daily practice, we observed that cluster designation 23 (CD23) (clone BU38) labels Merkel cells in normal skin. In this study, we examined the expression of CD23 in Merkel cell carcinoma (MCC) and assessed its usefulness in distinguishing MCC from non‐cutaneous small cell carcinoma (SMCC).

Methods:  Immunohistochemical staining of CD23 was performed on a total of 33 MCCs, 22 SMCCs and 5 carcinoid tumors.

Results:  CD23 reactivity was present in 32 of 33 (97%) MCCs, 18 of 22 (82%) SMCCs and 5 of 5 (100%) carcinoid tumors. In MCC, 19 cases (59%) showed a predominance of perinuclear dot‐like staining similar to cytokeratin 20, 3 (9%) showed mostly cytoplasmic staining and 10 (31%) displayed a combination of perinuclear dot‐like and cytoplasmic staining. In contrast, all CD23‐positive SMCCs and carcinoid tumors showed a diffuse cytoplasmic staining. There was a significant difference in the CD23 staining patterns between MCC and SMCC (p < 0.0001).

Conclusion:  CD23 is expressed in the majority of MCC, SMCC and carcinoid tumor irrespective of clinical outcome. The distinct punctate CD23 staining for MCC may be helpful in differentiating it from SMCC. To our knowledge, this is the first study to show the expression of CD23 in neuroendocrine tumors.
Disease burden of chronic lymphocytic leukaemia within the European Union
Authors: Watson Louise , Wyld Peter , Catovsky Daniel
Published: July 2008

Objective:  Whilst Chronic lymphocytic leukaemia (CLL) is considered a rare disease, to our knowledge, the current prevalence of CLL within the European Union (EU) member states is not published. Understanding the number of individuals with CLL is vital to assess disease burden within the wider population.

Methods:  Using 2002 data from the International Agency for Research on Cancer, we estimated the number of individuals with CLL (ICD‐10 C91.1) from those reported for all leukaemias (C91–95) and extrapolated the figures by the population increase within the EU between 2002 and 2006, the last year with fully updated community population estimates. One‐ and 5‐yr partial prevalence estimates are reported (i.e. the number of individuals still living 1–5 yr post‐diagnosis). We then applied proportional estimates from the literature to assess those requiring immediate treatment, those under observation and their likely progression rates.

Results:  We found that within the 27 EU states plus Iceland, Norway and Lichtenstein, 1‐ and 5‐yr CLL partial prevalence estimates totalled approximately 13 952 and 46 633 individuals respectively in 2006. By applying Binet staging to the 1‐yr estimate, 40% of patients will be stage B/C and require immediate treatment. Thus, 5581 individuals may be treated within the first year of diagnosis. Of the 60% (8371) under observation, by 5 yr up to 33% (2763) may have more advanced disease with increased risk of mortality.

Conclusion:  Whilst CLL is a rare disease, the number of individuals burdened by the disease within the EU is considerable and thousands of patients require treatment and physician care, which has cost implications for member states.
Hematopoietic progenitor cell colony growth differentiates chronic myelomonocytic leukemia from reactive monocytosis
Authors: Birrer Angelika , Jusufi Florije , Bernimoulin Michael , Tichelli André , Gratwohl Alois , Nissen‐Druey Catherine , Dirnhofer Stephan , Meyer‐Monard Sandrine , Stern Martin
Published: July 2008

In the absence of a cytogenetic abnormality or overt dysplasia, chronic myelomonocytic leukemia (CMML) may be difficult to be distinguished from reactive monocytosis. We have previously described a typical growth pattern in CMML patients, i.e., ‘pseudonormal’ colonies resembling granulocytic colonies but consisting entirely of monocytic cells when stained. To study the utility of the colony forming unit cell assay (CFU‐C) as a diagnostic tool in patients with monocytosis, we analyzed a cohort of 48 consecutive patients referred to our institution with peripheral blood monocytosis. Thirty‐six patients fulfilled the WHO criteria for CMML; 12 were diagnosed with reactive monocytosis. Of the patients with CMML, 28 showed pseudonormal growth with or without leukemic cluster growth, another four showed exclusively leukemic growth. None of the patients with reactive monocytosis showed either leukemic or pseudonormal growth. With a specificity of 100% and a sensitivity of 89%, the CFU‐C assay has a unique potential to distinguish CMML from reactive monocytosis.
Photocarcinogenesis of topical tazarotene and isotretinoin alone and in combination with valproic acid in hairless mice
Authors: Lerche Catharina M. , Philipsen Peter A. , Sehested Maxwell , Wulf Hans Christian
Published: July 2008

Abstract:  Retinoids  and the histone deacetylase inhibitor valproic acid have shown anticancer properties, but the photocarcinogenic or photoprotective effect is unclear. Therefore, we investigated whether a topical formulation of valproic acid is photocarcinogenic or photoprotective in hairless female C3.Cg/TifBomTac immunocompetent mice exposed to simulated solar radiation (SSR) and whether valproic acid changes the effect of the retinoids: tazarotene and isotretinoin. The products were applied on the dorsal skin of 400 mice (five times weekly) followed by SSR (three times weekly) 3–4 h after the application. This was performed during 12 months or until death. Tumors appeared sooner in groups treated with tazarotene and isotretinoin compared with that of the group treated with valproic acid and the control group. The present study shows that valproic acid alone is not photocarcinogenic or photoprotective in hairless mice. When valproic acid is combined with tazarotene or isotretinoin, it does not change their photocarcinogenicity significantly.
Evaluation of relative distance as new descriptor of yellow European eel spatial distribution
Authors: Imbert H. , De Lavergne S. , Gayou F. , Rigaud C. , Lambert P.
Published: July 2008

Abstract –  The spatial distribution of yellow European eel (Anguilla anguilla) smaller than 300 mm was analysed during the upstream colonisation process. A 9‐year electric‐fishing programme in the Gironde catchment (France) provided eel occurrence data in 256 sites and eel abundance data in 23 sites. Generalized linear models showed that small eel spatial distribution decreased with river slope, dam number and with downstream‐upstream distance, estimated using either the distance from the tidal limit, called ‘tidal distance’, or the ‘relative distance’, calculated as the fish’s position relative to the total distance between tidal limit and river source. This new descriptor should be considered in future eel distribution studies as it reveals fractal dimension in eel spatial distribution and may provide a standardised method to compare directly freshwater eel assessment between streams and catchments of different lengths. If the relevancy of this descriptor is subsequently confirmed, it may have important implications for the management of eel population conservation.
CD4+ T‐regulatory cells: toward therapy for human diseases
Authors: Allan Sarah E. , Broady Raewyn , Gregori Silvia , Himmel Megan E. , Locke Natasha , Roncarolo Maria Grazia , Bacchetta Rosa , Levings Megan K.
Published: July 2008

T‐regulatory cells (Tregs) have a fundamental role in the establishment and maintenance of peripheral tolerance. There is now compelling evidence that deficits in the numbers and/or function of different types of Tregs can lead to autoimmunity, allergy, and graft rejection, whereas an over‐abundance of Tregs can inhibit anti‐tumor and anti‐pathogen immunity. Experimental models in mice have demonstrated that manipulating the numbers and/or function of Tregs can decrease pathology in a wide range of contexts, including transplantation, autoimmunity, and cancer, and it is widely assumed that similar approaches will be possible in humans. Research into how Tregs can be manipulated therapeutically in humans is most advanced for two main types of CD4+ Tregs: forkhead box protein 3 (FOXP3)+ Tregs and interleukin‐10‐producing type 1 Tregs (Tr1 cells). The aim of this review is to highlight current information on the characteristics of human FOXP3+ Tregs and Tr1 cells that make them an attractive therapeutic target. We discuss the progress and limitations that must be overcome to develop methods to enhance Tregs in vivo, expand or induce them in vitro for adoptive transfer, and/or inhibit their function in vivo. Although many technical and theoretical challenges remain, the next decade will see the first clinical trials testing whether Treg‐based therapies are effective in humans.
Manipulating both the inhibitory and stimulatory immune system towards the success of therapeutic vaccination against chronic viral infections
Authors: Ha Sang‐Jun , West Erin E. , Araki Koichi , Smith Kendall A. , Ahmed Rafi
Published: July 2008

Summary: One potentially promising strategy to control chronic infections such as human immunodeficiency virus, hepatitis B virus, and hepatitis C virus is therapeutic vaccination, which aims to reduce persisting virus by stimulating a patient's own antiviral immune responses. However, this approach has fallen short of expectations, because antiviral T cells generated during chronic infections often become functionally exhausted and thus do not respond properly to therapeutic vaccination. Therefore, it is necessary to develop a therapeutic vaccine strategy to more effectively boost endogenous T‐cell responses to control persistent viral infections. Studies to elucidate the cause of impaired T‐cell function have pointed to sustained inhibitory receptor signaling through T‐cell expression of programmed death 1 (PD‐1). Recently, another inhibitory molecule, cytotoxic T lymphocyte antigen 4 (CTLA‐4), and also an immunosuppressive cytokine, interleukin 10 (IL‐10), have been reported to be potential factors of establishing immune suppression and viral persistence. Blocking these negative signaling pathways could restore the host immune system, enabling it to respond to further stimulation. Indeed, combining therapeutic vaccination along with the blockade of inhibitory signals could synergistically enhance functional CD8+ T‐cell responses and improve viral control in chronically infected mice, providing a promising strategy for the treatment of chronic viral infections. Furthermore, not only the ablation of negative signals but also the addition of stimulatory signals, such as interleukin 2 (IL‐2), might prove to be a potentially promising strategy to augment the efficacy of therapeutic vaccination against chronic viral infections.
CTLA‐4: a key regulatory point in the control of autoimmune disease
Authors: Scalapino Kenneth J. , Daikh David I.
Published: July 2008

Summary: Chronic autoimmune disease in humans is the result of a failure to control autoreactive immune cells in the periphery. This control is largely achieved by inhibition of newly activated and memory cells. A number of negative immune regulatory pathways have been characterized. The cell surface coreceptor cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4) has emerged as a critical attenuator of T‐cell activation and an essential component of the regulatory systems that serve to maintain peripheral tolerance. CTLA‐4 expression is induced on the surface of T cells after they have received a costimulatory signal from antigen‐presenting cells (APCs) via engagement of CD28 on the T‐cell surface. CTLA‐4 attenuates this costimulation by competing for CD28 ligands and through direct effects on APCs via the same ligands utilized by CD28. A large number of genetic association studies suggest that the CTLA‐4 gene is a locus of susceptibility to autoimmune disease. However, specific functional defects in the CTLA‐4 gene in patients have not been identified to date. Elucidating the role of CTLA‐4 in immune tolerance has also led to a number of therapeutic applications, particularly in the treatment of malignancy and autoimmune disease.
Integrin‐associated proteins as potential therapeutic targets
Authors: Cantor Joseph M. , Ginsberg Mark H. , Rose David M.
Published: July 2008

Summary: Integrins are adhesion receptors important for hematopoiesis, leukocyte trafficking, and formation of immunological synapses; hence, they may provide targets for therapeutic intervention in leukocyte‐driven pathologies. Blocking integrin–ligand binding is one strategy for inhibiting integrins; however, a complete loss of integrin function can lead to mechanism‐based toxicities. Because integrin α and β subunits interact with a variety of other proteins to receive and transmit cellular signals, targeting these integrin‐associated proteins may utilize alternative sites for intervention that lead to therapies with fewer side effects. This review summarizes integrin‐associated proteins in leukocytes and focuses on four of these proteins with perceived therapeutic potential. Specific mutations in the α4 integrin cytoplasmic tail block or enforce binding to paxillin and thus modulate integrin signaling required for efficient cell migration. Similarly, the association of RAPL(NORE1B) with β2 integrins may participate in adhesive and migratory events in leukocytes. The β integrin cytoplasmic tail‐binding protein talin is critical for increasing the affinity of integrins (activation), and blockade of talin binding can prevent leukocyte arrest on the endothelium. Finally, the membrane protein CD98 mediates β1 and β3 integrin signaling and may be involved in leukocyte functions. Identification of biologically important interactions of integrins and signaling proteins can thus pave the way to new strategies for manipulating leukocyte functions.
The spectrum of complement alternative pathway‐mediated diseases
Authors: Holers V. Michael
Published: July 2008

Summary: The complement system has once again come into prominence in the therapeutic development arena. The recent approval of an inhibitory monoclonal antibody, eculizumab, which is directed against complement component C5 for the disease paroxysmal nocturnal hemoglobinuria has provided the initial validation of this system as a therapeutic target. Preclinical studies using animal models and human‐derived samples demonstrate that inhibition of complement ameliorates many inflammatory and autoimmune disease manifestations. Major efforts continue to define the most optimal means to block complement activation in a cost‐effective manner. Because the system is initiated through three pathways and generates at least six immunoregulatory and pro‐inflammatory mediators, there is substantial complexity to this problem. One pathway, designated the alternative pathway, has recently been shown to play a particularly important role in preclinical disease models. Further evidence of the importance of the alternative pathway has been provided by studies of human diseases, where mutations or dysfunctional polymorphisms that promote activation of this pathway are highly associated with the diseases atypical hemolytic uremic syndrome, dense deposit disease, and age‐related macular degeneration. This article reviews evidence in support of the essential role of the alternative pathway in the generation of tissue injury and the rationale for development of therapies that modulate its activity.
How the study of children with rheumatic diseases identified interferon‐α and interleukin‐1 as novel therapeutic targets
Authors: Pascual Virginia , Allantaz Florence , Patel Pinakeen , Palucka A. Karolina , Chaussabel Damien , Banchereau Jacques
Published: July 2008

Summary: Our studies in children with rheumatic diseases have led to the identification of two of the oldest cytokines, type I interferon (IFN) and interleukin 1 (IL‐1), as important pathogenic players in systemic lupus erythematosus (SLE) and systemic onset juvenile arthritis (SoJIA), respectively. These findings were obtained by studying the transcriptional profiles of patient blood cells and by assessing the biological and transcriptional effect(s) of active patient sera on healthy blood cells. We also identified a signature that can be used to promptly diagnose SoJIA from other febrile conditions. Finally, our pilot clinical trials using IL‐1 blockers have shown remarkable clinical benefits in SoJIA patients refractory to other medications.
Modulating tone: the overture of S1P receptor immunotherapeutics
Authors: Rosen Hugh , Gonzalez‐Cabrera Pedro , Marsolais David , Cahalan Stuart , Don Anthony S. , Sanna M. Germana
Published: July 2008

Summary: Modulation of complex functions within the immune system has proven to be surprisingly sensitive to alterations in the lysophospholipid sphingosine 1‐phosphate (S1P) receptor‐ligand rheostat. This has become increasingly evident from both chemical and genetic manipulation of the S1P system, with pharmacological effects upon lymphoid cells, dendritic cell function, as well as vascular interfaces. The integrated immune system, perhaps as a result of its relatively recent evolutionary ontogeny, has selected for a number of critical control points regulated by five distinct high affinity G‐protein‐coupled receptor subtypes with a shared ligand, with receptors distributed on lymphocytes, dendritic cells, and endothelium. All of these cellular components of the axis are capable of modulating immune responses in vivo, with the impact on the immune response being very different from classical immunosuppressants, by virtue of selective spatial and temporal sparing of humoral and myeloid elements of host defense. Pharmacological subversion of the S1P rheostat is proving to be clinically efficacious in multiple sclerosis, and both the scope and limitations of therapeutic modulation of the S1P axis in immunotherapy are becoming clearer as understanding of the integrated chemical physiology of the S1P system emerges.
Melatonin decreases matrix metalloproteinase‐9 activation and expression and attenuates reperfusion‐induced hemorrhage following transient focal cerebral ischemia in rats
Authors: Hung Yu‐Chang , Chen Tsung‐Ying , Lee E‐Jian , Chen Wan‐Ling , Huang Sheng‐Yang , Lee Wei‐Ting , Lee Ming‐Yang , Chen Hung‐Yi , Wu Tian‐Shung
Published: July 2008

Abstract:  We have previously shown that melatonin reduces postischemic rises in the blood–brain barrier (BBB) permeability and improves neurovascular dysfunction and hemorrhagic transformation following ischemic stroke. It is known that activation of the matrix metalloproteinases (MMPs) plays a crucial role in the pathogenesis of brain edema and hemorrhagic transformation after ischemic stroke. We, herein, investigated whether melatonin would ameliorate MMP‐2 and MMP‐9 activation and expression in a rat model of transient focal cerebral ischemia. Adult male Sprague–Dawley rats were subjected to a 90‐min middle cerebral artery (MCA) occlusion using an intraluminal filament. Melatonin (5 mg/kg) or vehicle was intravenously injected upon reperfusion. Brain infarction and hemorrhage within infarcts were measured, and neurological deficits were scored. The activity and expression of MMP‐2 and MMP‐9 were determined by zymography, in situ zymography and Western immunoblot analysis. Cerebral ischemia–reperfusion induced increased pro‐MMP‐9 and MMP‐9 activity and expression 24 hr after reperfusion onset. Relative to controls, melatonin‐treated animals, however, had significantly reduced levels in the MMP‐9 activity and expression (P < 0.01), in addition to reduced brain infarct volume and hemorrhagic transformation as well as improved sensorimotor neurobehavioral outcomes. No significant change in MMP‐2 activity was observed throughout the course experiments. Our results indicate that the melatonin‐mediated reductions in ischemic brain damage and reperfusion‐induced hemorrhage are partly attributed to its ability to reduce postischemic MMP‐9 activation and increased expression, and further support the fact that melatonin is a suitable as an add‐on to thrombolytic therapy for ischemic stroke patients.
Endosomal Functions in Plants
Authors: Otegui Marisa S. , Spitzer Christoph
Published: July 2008

Plant endosomes are highly dynamic organelles that are involved in the constitutive recycling of plasma membrane cargo and the trafficking of polarized plasma membrane proteins such as auxin carriers. In addition, recent studies have shown that surface receptors such as the plant defense‐related FLS2 receptor and the brassinosteroid receptor BRI1 appear to signal from endosomes upon ligand binding and internalization. In yeast and mammals, endosomes are also known to recycle vacuolar cargo receptors back to thetransGolgi network and sort membrane proteins for degradation in the vacuole/lysosome. Some of these sorting mechanisms are mediated by the retromer and endosomal sorting complex required for transport (ESCRT) complexes. Plants contain orthologs of all major retromer and ESCRT complex subunits, but they have also evolved variations in endosomal functions connected to plant‐specific features such as the diversity of vacuolar transport pathways. This review focuses on recent studies in plants dealing with the regulation of endosomal recycling functions, architecture and formation of multivesicular bodies, ligand‐mediated endocytosis and receptor signaling from endosomes as well as novel endosomal markers and the function of endosomes in the transport and processing of soluble vacuolar proteins.
A randomized clinical trial of chlorhexidine in the maintenance of oral candidiasis‐free period in HIV infection
Authors: Nittayananta W , DeRouen TA , Arirachakaran P , Laothumthut T , Pangsomboon K , Petsantad S , Vuddhakul V , Sriplung H , Jaruratanasirikul S , Martin MD
Published: July 2008

Objective:  To determine if chlorhexidine can be used as an intervention to prolong the time to relapse of oral candidiasis.

Subjects and methods:  A double‐blinded randomized clinical trial was performed in 75 HIV/AIDS subjects with oral candidiasis. Clotrimazole troche was prescribed, and the subjects were re‐examined every 2 weeks until the lesions were completely eradicated. The subjects were then randomly divided into two groups; 0.12% chlorhexidine (n = 37, aged 22–52 years, mean 34 years) and 0.9% normal saline (n = 38, aged 22–55 years, mean 38 years). They were re‐examined every 2 weeks until the next episode was observed.

Results:  The time to recurrence of oral candidiasis between the chlorhexidine and the saline group was not statistically significant (P > 0.05). The following variables were significantly associated with the time of recurrence; frequency of antifungal therapy (P = 0.011), total lymphocyte (P = 0.017), alcohol consumption (P = 0.043), and candidiasis on gingiva (P = 0.048). The subjects with lower lymphocyte showed shorter oral candidiasis‐free periods (P = 0.034).

Conclusions:  Chlorhexidine showed a small but not statistically significant effect in maintenance of oral candidiasis‐free period. This lack of significance may be due to the small sample size. Further study should be performed to better assess the size of the effect, or to confirm our findings.
Expression of human β‐defensin ‐1, ‐2, and ‐3 in non‐inflamed pseudocyst, mucoceles
Authors: Frederic MK , Yamaai T , Mizukawa N , Kaneda Y , Katase N , Gunduz M , Nagatsuka H , Sugahara T
Published: July 2008

Objectives and design:  The expressions of human beta defensin‐1 (HBD‐1), ‐2 (HBD‐2) and ‐3 (HBD‐3) in non‐inflamed pseudocysts such as mucoceles were investigated immunohistochemically in this study.

Materials and methods:  Mucocele specimens were obtained from 21 patients. The expression of HBDs was studied immunohistochemically by using antibodies directed against HBD‐1, ‐2, and ‐3. Statistical analyses were carried out on serial sections stained with antibodies.

Results:  Cells expressing HBDs were found in mucoceles. The expression of HBD‐2 was observed in floating cells in all the specimens, whereas HBD‐1 and HBD‐3‐expressing cells were detected in 93% and 73% of the mucoceles, respectively. The HBD‐2 signal was the most intense and the HBD‐3 signal intensity was weaker than that of HBD‐1. HBDs were expressed in neutrophils and in other floating cells. Interestingly, the signal intensity and the population of positive cells located close to the centers of cysts were higher than those located in the peripheral areas of cysts.

Conclusion:  The expression of HBDs was found even in non‐inflamed pseudocysts such as mucoceles. These results suggest that an unknown mechanism not involved in biophylaxis for the expression of HBDs may exist.
SK3 K+ channel‐deficient mice have enhanced dopamine and serotonin release and altered emotional behaviors
Authors: Jacobsen J. P. R. , Weikop P. , Hansen H. H. , Mikkelsen J. D. , Redrobe J. P. , Holst D. , Bond C. T. , Adelman J. P. , Christophersen P. , Mirza N. R.
Published: July 2008

SK3 K+ channels influence neuronal excitability and are present in 5‐hydroxytryptamine (5‐HT) and dopamine (DA) nuclei in the brain stem. We therefore hypothesized that SK3 channels affect 5‐HT and DA neurotransmission and associated behaviors. To explore this, we used doxycycline‐induced conditional SK3‐deficient (T/T) mice. In microdialysis, T/T mice had elevated baseline levels of striatal extracellular DA and the metabolites dihydroxyphenylacetic acid and homovanillic acid. While baseline hippocampal extracellular 5‐HT was unchanged in T/T mice, the 5‐HT response to the 5‐HT transporter inhibitor citalopram was enhanced. Furthermore, baseline levels of the 5‐HT metabolite 5‐hydroxyindoleacetic acid were elevated in T/T mice. T/T mice performed equally to wild type (WT) in most sensory and motor tests, indicating that SK3 deficiency does not lead to gross impairments. In the forced swim and tail suspension tests, the T/T mice displayed reduced immobility compared with WT, indicative of an antidepressant‐like phenotype. Female T/T mice were more anxious in the zero maze. In contrast, anxiety‐like behaviors in the open‐field and four‐plate tests were unchanged in T/T mice of both sexes. Home cage diurnal activity was also unchanged in T/T mice. However, SK3 deficiency had a complex effect on activity responses to novelty: T/T mice showed decreased, increased or unchanged activity responses to novelty, depending on sex and context. In summary, we report that SK3 deficiency leads to enhanced DA and 5‐HT neurotransmission accompanied by distinct alterations in emotional behaviors.
MAGNETIC RESONANCE IMAGING OF FELINE HIPPOCAMPAL NECROSIS
Authors: SCHMIED OLIVER , SCHARF GERNOT , HILBE MONIKA , MICHAL ULRIKE , TOMSA KAMIL , STEFFEN FRANK
Published: July 2008

The clinical, neuropathologic, and magnetic resonance (MR) imaging features in four cats with necrosis of the hippocampus and piriform lobe are described. All cats had acute generalized seizures and behavioral changes including aggression, salivation, polyphagia, and disorientation. Routine hematologic, serum chemistry, and cerebrospinal fluid analyses were normal. MR imaging abnormalities were restricted to the area of the hippocampus and piriform lobe. The lesions were T2‐hyperintense, T1‐hypointense, and were characterized by various degrees of contrast enhancement. Lesions were consistent with necrotizing encephalitis. Two cats were euthanized and underwent postmortem examination within a week after MR imaging due to the lack of response to antiepileptic drug therapy and progressive neuropathy. The remaining two cats lived for about four months and were then euthanized because of persistent behavioral and neurologic signs; only one of these cats underwent postmortem examination with histopathologic examination. Histopathological findings were typical of severe, diffuse, bilateral symmetric necrosis, and degeneration of neurons in the hippocampus and piriform lobe, but an etiologic agent was not apparent. This apparently unique feline syndrome, now reported in Switzerland and Italy, has no known cause at this time.
SCINTIGRAPHIC AND RADIOGRAPHIC EVALUATION OF APPENDICULAR SKELETAL LESIONS IN COLD‐STUNNED KEMP'S RIDLEY SEA TURTLES
Authors: SOLANO MAURICIO , INNIS CHARLES , SMITH CYNTHIA , MERIGO CONSTANCE , WEBER III ERNEST SCOTT
Published: July 2008

Osteolytic appendicular skeletal lesions in eight‐stranded, cold‐stunned Kemp's ridley sea turtles (Lepidochelys kempii) were evaluated using radiography and skeletal scintigraphy. Radiographic studies were performed monthly in most animals. Follow‐up scintigraphy was performed 45–120 days after the initial exams in six turtles. Radiographically, lesions slowly progressed from an early osteolytic process contained to either the proximal or distal end of long bones, to a later stage characterized by thickening of the affected bone, sclerosis, and remodeling of the lesion borders. In seven turtles, the initial scintigrams were characterized by at least one focus of abnormal radiopharmaceutical uptake that correlated with a lytic site noted in radiographs. In five turtles, scintigraphic lesions were characterized by asymmetric radiopharmaceutical uptake rather than by increased intensity of uptake. Scintigraphic studies obtained more than 4 months after the appearance of clinical and radiographic signs had minimal, if any, abnormal radiopharmaceutical uptake, despite the persistence of abnormal radiographic findings. Skeletal scintigraphy is an effective method for more precisely determining if and when these animals can be returned to the wild. Animals were released if normal radiopharmaceutical uptake was seen during initial examination, or if decreased uptake was noted between serial examinations. In four of the turtles, resolution of abnormal scintigraphic findings permitted an objective decision to discontinue antibiotic and antifungal therapy. Seven of the eight turtles were released after correlation of the clinical signs with the imaging findings. Radiographs, however, are still needed to facilitate the correct identification of lesions with scintigraphy.
USE OF SURGICAL HEMOCLIPS IN RADIATION TREATMENT PLANNING
Authors: McENTEE MARGARET C. , STEFFEY MICHELE , DYKES NATHAN L.
Published: July 2008

The goal of this prospective study was to determine the effect of hemoclip use on the size of radiation treatment fields based on a 3‐cm margin around a surgical incision alone (field setup 1) vs. a 3‐cm margin around the surgical incision plus hemoclips (field setup 2). Forty‐seven dogs that underwent surgical resection of a total of 55 soft tissue masses had surgical hemoclips placed at the time of surgery and orthogonal radiographs made immediately postoperatively. Radiation treatment field simulation was done and field areas measured. Additional determinations included number of hemoclips outside of the radiation treatment field based on a margin around the incision alone, hemoclip distance from the incision, and association between incision length and greatest distance of hemoclips from the incision. There was a significant difference in radiation treatment field size using information regarding the location of hemoclips in conjunction with the surgical scar compared with the surgical scar alone for truncal (P=0.0003) vs. extremity tumors (P=0.087). In simulating radiation treatment fields hemoclips were located outside of field setup 1 for the majority of tumors (79%) resected from the trunk but only in a minority of tumors (10.7%) resected from extremity sites. The findings from this study suggest that surgical hemoclips have potential utility in simulation of radiation treatment fields in the postoperative setting.