Lichenoid dermatitis preceding Stevens-Johnson syndrome in a patient treated with nivolumab.

Nivolumab is an immune checkpoint inhibitor acting on programmed cell death protein 1 (PD-1) that has been used to treat a growing number of malignancies. Cutaneous side effects are common with nivolumab treatment, though they are typically self-limited. Here we present a case of persistent lichenoid dermatitis in a patient treated with nivolumab for renal cell cancer. The patient then developed Stevens-Johnson syndrome 9 months after initiation of nivolumab, with no other identifiable offending medication in the interim. Although an unusual presentation, a growing number of cases have reported delayed Stevens-Johnson syndrome/toxic epidermolytic necrosis-like reactions to immune checkpoint inhibitors. Awareness of this phenomenon is imperative for prompt recognition and treatment of potentially life-threatening cutaneous side effects.

Musculoskeletal sarcoidosis: A single center experience over 15 years.

BACKGROUND: Musculoskeletal (MSK) sarcoidosis presents with a variety of clinical phenotypes. Four subtypes of MSK sarcoidosis have been identified to date: Lofgren syndrome, chronic sarcoid arthritis, osseous sarcoidosis, sarcoid myopathy. Each subtype has been reported with varying incidence mainly due to lack of universal classification criteria. METHODS: We performed a retrospective chart review of patients with MSK sarcoidosis at a single academic center between January 2000 and December 2014. Descriptive statistics were used to describe the proportion of patients with sarcoidosis who had the 4 MSK syndromes of interest, demographic characteristics and therapeutic agents used. RESULTS: A cohort of 58 patients with MSK manifestations were identified among 1016 patients with sarcoidosis. Frequency of subtypes include: Lofgren syndrome 46.6%, osseous sarcoidosis 25.9%, chronic sarcoid arthritis 24.1% and sarcoid myopathy 6.9%. The cohort was predominantly female (43/58 patients, 74%) and Caucasian (48/58 patients, 82.8%). Mean age was 47.2 years. One patient had overlap of osseous sarcoidosis and chronic sarcoid arthritis, another patient initially had Lofgren syndrome and later developed chronic sarcoid arthritis. Sarcoid myopathy patients presented with myalgia more often than muscle weakness. CONCLUSION: We identified a large cohort of MSK sarcoidosis and determined the prevalence of all 4 subtypes. In patients who do develop MSK manifestations of sarcoidosis, they are commonly a part of the initial presentation of sarcoidosis. There is an unmet need to establish standardized classification criteria for the 4 MSK sarcoidosis syndromes.

The small heat shock protein HSPB1 protects mice from sepsis.

In vitro studies have implicated the small heat shock protein HSPB1 in a range of physiological functions. However, its in vivo relevance is unclear as the phenotype of unstressed HSPB1-/- mice is unremarkable. To determine the impact of HSPB1 in injury, HSPB1-/- and wild type (WT) mice were subjected to cecal ligation and puncture, a model of polymicrobial sepsis. Ten-day mortality was significantly higher in HSPB1-/- mice following the onset of sepsis (65% vs. 35%). Ex vivo mechanical testing revealed that common carotid arteries from HSPB1-/- mice were more compliant than those in WT mice over pressures of 50-120 mm Hg. Septic HSPB1-/- mice also had increased peritoneal levels of IFN-γ and decreased systemic levels of IL-6 and KC. There were no differences in frequency of either splenic CD4+ or CD8+ T cells, nor were there differences in apoptosis in either cell type. However, splenic CD4+ T cells and CD8+ T cells from HSPB1-/- mice produced significantly less TNF and IL-2 following ex vivo stimulation. Systemic and local bacterial burden was similar in HSPB1-/- and WT mice. Thus while HSPB1-/- mice are uncompromised under basal conditions, HSPB1 has a critical function in vivo in sepsis, potentially mediated through alterations in arterial compliance and the immune response.

Staphylococcus caprae bacteraemia and native bone infection complicated by therapeutic failure and elevated MIC: a case report.

Introduction.Staphylococcus caprae is a coagulase-negative staphylococcus that has been reported in several cases as a human pathogen. However, it has rarely been reported as pathogen in native bone. Furthermore, the reported MIC levels noted in the literature for vancomycin were <2 µg ml-1making vancomycin a first line choice for infected patients. Case presentation. We report a case of Staphylococcus caprae causing osteomyelitis of the lumbar spine and bacteraemia and resulting in sepsis and ultimately the demise of a patient despite appropriate prolonged antibiotic therapy. Conclusion.Staphylococcus caprae has been reported as a human pathogen since 1983 when it was discovered. We report a case involving native bone infection which is rare in the absence of mechanical hardware. Furthermore, this strain had an elevated MIC for vancomycin which has not been reported in the literature.

Effect of HSP25 loss on muscle contractile function and running wheel activity in young and old mice.

Aging is associated with an adverse decline in muscle function, often manifesting as decreased strength and increased muscle fatigability that negatively affects the overall health of the elderly. Heat shock proteins (HSPs), a family of stress inducible proteins known to protect cells from damage, are highly induced in muscle cells following exercise, but both basal and inducible levels decline with age. Utilizing young and old mice lacking HSP25 (Hsp25(-/-)) we tested the hypothesis that HSP25 is required to maintain normal muscle function and that age related decreases in HSP25 directly contribute to declining muscle function. Running wheel distances over 14 days for young Hsp25(-/-) mice were significantly lower than for the corresponding Hsp25(+/+) genotype (81238 vs. 33956 AUC, respectively). While older groups both ran significantly less than young groups, in aged mice HSP25 loss did not lead to any additional decrease. Significantly lower myofibrillar (contractile) protein levels in young Hsp25(-/-) vs. Hsp25(+/+) (15.7 ± 0.2 vs. 13.4 ± 0.3 mg/mg muscle) mice suggests HSP25 loss was associated with greater muscle breakdown during voluntary wheel running. In vivo, plantarflexor maximal isometric force was significantly decreased in aged vs. young mice, but the loss of HSP25 had no effect on either group. However, plantarflexor fatigability over 10 contractions was significantly higher in young Hsp25(-/-) vs. Hsp25(+/+) mice (59 ± 3 vs. 49 ± 4% of initial force, respectively) but no similar effect of genotype was detected in the older groups. There was no difference in muscle caspase-3 activity between Hsp25(-/-) and Hsp25(+/+ mice), whether young or old, but there was a significant genotype independent increase in activity with age. Overall, the results suggest that the absence of HSP25 primarily contributes to muscle fatigue resistance, rather than maximal force production, and that this effect is most evident in young compared to older mice.

Inhibition of heat shock induction of heat shock protein 70 and enhancement of heat shock protein 27 phosphorylation by quercetin derivatives.

Inhibitors of heat-induced heat shock protein 70 (HSP70) expression have the potential to enhance the therapeutic effectiveness of heat-induced radiosensitization of tumors. Among known small molecule inhibitors, quercetin has the advantage of being easily modified for structure-activity studies. Herein, we report the ability of five monomethyl and five carbomethoxymethyl derivatives of quercetin to inhibit heat-induced HSP70 expression and enhance HSP27 phosphorylation in human cells. While quercetin and several derivatives inhibit HSP70 induction and enhance HSP27 phosphorylation at Ser78, other analogues selectively inhibit HSP70 induction without enhancing HSP27 phosphorylation that would otherwise aid in cell survival. We also show that good inhibitors of HSP70 induction are also good inhibitors of both CK2 and CamKII, kinases that are known to activate HSP70 expression by phosphorylation of heat shock transcription factor 1. Derivatives that show poor inhibition of either or both kinases are not good inhibitors of HSP70 induction, suggesting that quercetin's effectiveness is due to its ability to inhibit both kinases.

Anti-apoptotic peptides protect against radiation-induced cell death.

The risk of terrorist attacks utilizing either nuclear or radiological weapons has raised concerns about the current lack of effective radioprotectants. Here it is demonstrated that the BH4 peptide domain of the anti-apoptotic protein Bcl-xL can be delivered to cells by covalent attachment to the TAT peptide transduction domain (TAT-BH4) and provide protection in vitro and in vivo from radiation-induced apoptotic cell death. Isolated human lymphocytes treated with TAT-BH4 were protected against apoptosis following exposure to 15Gy radiation. In mice exposed to 5Gy radiation, TAT-BH4 treatment protected splenocytes and thymocytes from radiation-induced apoptotic cell death. Most importantly, in vivo radiation protection was observed in mice whether TAT-BH4 treatment was given prior to or after irradiation. Thus, by targeting steps within the apoptosis signaling pathway it is possible to develop post-exposure treatments to protect radio-sensitive tissues.