138 research outputs found
The effect of gluon condensate on holographic heavy quark potential
The gluon condensate is very sensitive to the QCD deconfinement transition
since its value changes drastically with the deconfinement transition. We
calculate the gluon condensate dependence of the heavy quark potential in
AdS/CFT to study how the property of the heavy quarkonium is affected by a
relic of the deconfinement transition. We observe that the heavy quark
potential becomes deeper as the value of the gluon condensate decreases. We
interpret this as a dropping of the heavy quarkonium mass just above the
deconfinement transition, which is similar to the results obtained from QCD sum
rule and from a bottom-up AdS/QCD model.Comment: 16 pages, 6 figures, typos corrected, references adde
Determinants of mTOR inhibitor therapy in AIDS-associated malignancies
Rapamycin/Sirolimusâą leads to the regression of transplant-
associated Kaposi sarcoma (KS). It also leads to
disease stabilization in HIV-associated KS. Case reports
and a wealth of preclinical studies support rapamycinâs
efficacy also in AIDS associated lymphoma, such as primary
effusion lymphoma (PEL). Rapamycin inhibits the
mammalian target of rapamycin (mTOR) and papamycin
derivatives are approved for the treatment of mantle
cell lymphoma and other cancers. It is not universally
effective against all solid tumors. Even within this group
of clinically responsive cancers, there are exceptions of
cases or cell models in which this drug or its derivatives
(rapalogs) fail
Cytokine Homologs of Human Gammaherpesviruses
Gammaherpesviruses such as Epstein-Barr virus (EBV, human herpesvirus 4) and Kaposi sarcoma-associated herpesvirus (KSHV, human herpesvirus 8) establish lifelong infection in the host. To further this lifestyle, they encode homologs of cellular cytokines and cytokine receptors with the overarching goal to escape from or to blunt host antiviral defenses. EBV encodes mimics of human interleukin (hIL)-10 and a G protein-coupled receptor protein with sequence similarity to CXCR, whereas KSHV encodes homologs of hIL-6, 3 CC chemokine ligands, and a G protein-coupled receptor with sequence similarity to IL8 receptor alpha. This review focuses on the EBV IL-10 homolog and the KSHV IL-6 homolog with respect to virus biology and pathogenesis of the virus-associated diseases
Animal models of tumorigenic herpesvirusesâan update
Any one model system, be it culture or animal, only recapitulates one aspect of the viral life cycle in the human host. By providing recent examples of animal models for Epstein Barr Virus and Kaposi Sarcoma-associated Herpesvirus, we would argue that multiple animal models are needed to gain a comprehensive understanding of the pathogenesis associated with human oncogenic herpesviruses. Transgenic mice, homologous animal herpesviruses, and tumorgraft and humanized mouse models all complement each other in the study of viral pathogenesis. The use of animal model systems facilitates the exploration of novel antiviral and anti-cancer treatment modalities for diseases associated with oncogenic herpesviruses
A Dual Geometry of the Hadron in Dense Matter
We identify the dual geometry of the hadron phase of dense nuclear matter and
investigate the confinement/deconfinement phase transition. We suggest that the
low temperature phase of the RN black hole with the full backreaction of the
bulk gauge field is described by the zero mass limit of the RN black hole with
hard wall. We calculated the density dependence of critical temperature and
found that the phase diagram closes. We also study the density dependence of
the rho meson mass.Comment: 16 pages, 4 figures, typos corrected, references adde
Kaposi's Sarcoma-Associated Herpesvirus Latency Locus Compensates for Interleukin-6 in Initial B Cell Activation
Interleukin 6 (IL-6) is considered a proliferation and survival factor for B cells. To assess the role of IL-6 in Kaposi sarcoma-associated herpesvirus (KSHV) latency, KSHV latency locus-transgenic mice (referred to as latency mice) lacking IL-6 were evaluated. IL-6 â/â latency mice had the same phenotypes as the latency mice, i.e., increased frequency of marginal zone B cells, hyperplasia, and hyperglobulinemia, indicating that the KSHV latency locus, which includes all viral microRNAs (miRNAs), can compensate for lack of IL-6 in premalignant B cell activation
Hsp90 Inhibitors Are Efficacious against Kaposi Sarcoma by Enhancing the Degradation of the Essential Viral Gene LANA, of the Viral Co-Receptor EphA2 as well as Other Client Proteins
Heat-shock protein 90 (Hsp90) inhibitors exhibit activity against human cancers. We evaluated a series of new, oral bioavailable, chemically diverse Hsp90 inhibitors (PU-H71, AUY922, BIIB021, NVP-BEP800) against Kaposi sarcoma (KS). All Hsp90 inhibitors exhibited nanomolar EC50 in culture and AUY922 reduced tumor burden in a xenograft model of KS. KS is associated with KS-associated herpesvirus (KSHV). We identified the viral latency associated nuclear antigen (LANA) as a novel client protein of Hsp90 and demonstrate that the Hsp90 inhibitors diminish the level of LANA through proteasomal degradation. These Hsp90 inhibitors also downregulated EphA2 and ephrin-B2 protein levels. LANA is essential for viral maintenance and EphA2 has recently been shown to facilitate KSHV infection; which in turn feeds latent persistence. Further, both molecules are required for KS tumor formation and both were downregulated in response to Hsp90 inhibitors. This provides a rationale for clinical testing of Hsp90 inhibitors in KSHV-associated cancers and in the eradication of latent KSHV reservoirs
Acral-type Malignant Acanthosis Nigricans Associated with Gastric Adenocarcinoma
Acanthosis nigricans is a symmetric eruption characterized by the presence of a hyperpigmented, velvety cutaneous thickening, that can develop on any part of the body, but characteristically affects the flexural areas of the body. The velvety hyperkeratotic lesions can be located on the dorsum of the hands and feet in dark-skinned people in the form of a variant of acanthosis nigricans called as acral acanthotic anomaly or acral type acanthosis nigricans. Although acanthosis nigricans is associated with malignant tumors, particularly gastric carcinoma, acral type acanthosis nigricans has never been reported to be associated with gastric adenocarcinoma. In our present study, we describe a case of 58-year-old man with acral type acanthosis nigricans and its association with carcinoma of the stomach; a marked improvement was seen in the skin condition of the patient with chemotherapy
Pseudocyst of the Scalp
Pseudocyst of the scalp is described in the Japanese literature as a skin-colored cystic tumor localized on the forehead, whereas alopecic and aseptic nodules of the scalp are described in the French literature as asymptomatic nodules on the scalp that lack a pseudocyst-like architecture. The etiology of these diseases is unknown, but the lesions are likely due to follicular occlusion. Here, we report a case of pseudocyst of the scalp in a 72-year-old woman. The patient had a dome-shaped painless tumor on her scalp. Histologic examination showed a pseudocyst-like architecture with no true cystic wall. Here, we report a case of pseudocyst of the scalp and summarize the characteristic features of both pseudocyst of the scalp and alopecic and aseptic nodules of the scalp
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