Real-world effectiveness of antifungal prophylaxis with posaconazole as the primary agent in patients with haematological malignancies.

BACKGROUND AND OBJECTIVES: Patients undergoing induction/reinduction chemotherapy for haematologic malignancies (HM) are at risk for invasive fungal infections (IFIs). In 2015, Duke University Hospital (DUH) implemented a new standardised fungal prophylaxis protocol for adult patients undergoing induction chemotherapy for acute lymphocytic leukaemia, acute myelocytic leukaemia and myelodysplastic syndrome. This study assessed the impact of protocol implementation on (1) use of antifungal prophylaxis, throughout the at-risk period and (2) patient outcomes such as IFI and mortality. METHODS: Retrospective, observational study of adult HM patients admitted to DUH for induction/reinduction chemotherapy pre- (7/1/2013-12/31/2014) and post- (1/1/2015-10/31/2016) implementation of standardised antifungal prophylaxis protocol (which recommended posaconazole as the first-line agent). Patients were followed for up to 100 days after initiation of induction chemotherapy to evaluate use of antifungal prophylaxis and patient outcomes. RESULTS: 218 patients with haematologic malignancies were included (90 pre, 128 post). Use of antifungal prophylaxis increased from 81.1% (pre) to 97.7% (post) (p < .0001). Overall, 71% received posaconazole as initial antifungal prophylaxis (64.4% pre, 75.7% post). Approximately one-fourth of patients (25.6%, pre vs 26.6%, post) developed an IFI (proven/probable or possible using modified EORTC definitions) (p = .868); 100-day mortality remained stable (18.9% pre vs 18.8% post, respectively, p = .979). Lack of antifungal prophylaxis and older age (≥60 years) were associated with higher risk of IFI. CONCLUSION: Implementation of a standardised protocol with posaconazole as the primary agent was associated with increased use of antifungal prophylaxis among patients undergoing induction/reinduction chemotherapy for haematologic malignancies in our hospital. Lack of antifungal prophylaxis was an independent predictor of IFIs, underscoring the importance of prophylaxis in this at-risk population.

Trichodysplasia spinulosa: Case reports and review of literature.

Trichodysplasia spinulosa (TS) is a rare skin condition caused by trichodysplasia spinulosa-associated polyomavirus (TSPyV). It affects immunosuppressed patients, and <50 cases have been reported. The majority of these cases are seen in solid organ transplant recipients. TS often poses a diagnostic and therapeutic challenge because of its rarity and resemblance with other skin conditions. Several forms of treatment are usually tried prior to establishing a definitive diagnosis. Oral valganciclovir and topical cidofovir have been found to give the best results and hence are the most commonly used agents once the diagnosis is established. Here, we present two cases with a review of literature of TS in solid organ transplant recipients, focusing on time to develop the condition post-transplant, immunosuppression regimen used, and treatment initiated both before and after a definitive diagnosis.

A TfR-Binding Cystine-Dense Peptide Promotes Blood-Brain Barrier Penetration of Bioactive Molecules.

The impenetrability of the blood-brain barrier (BBB) to most conventional drugs impedes the treatment of central nervous system (CNS) disorders. Interventions for diseases like brain cancer, neurodegeneration, or age-associated inflammatory processes require varied approaches to CNS drug delivery. Cystine-dense peptides (CDPs) have drawn recent interest as drugs or drug-delivery vehicles. Found throughout the phylogenetic tree, often in drug-like roles, their size, stability, and protein interaction capabilities make CDPs an attractive mid-size biologic scaffold to complement conventional antibody-based drugs. Here, we describe the identification, maturation, characterization, and utilization of a CDP that binds to the transferrin receptor (TfR), a native receptor and BBB transporter for the iron chaperone transferrin. We developed variants with varying binding affinities (KD as low as 216 pM), co-crystallized it with the receptor, and confirmed murine cross-reactivity. It accumulates in the mouse CNS at ~25% of blood levels (CNS blood content is only ~1%-6%) and delivers neurotensin, an otherwise non-BBB-penetrant neuropeptide, at levels capable of modulating CREB signaling in the mouse brain. Our work highlights the utility of CDPs as a diverse, easy-to-screen scaffold family worthy of inclusion in modern drug discovery strategies, demonstrated by the discovery of a candidate CNS drug delivery vehicle ready for further optimization and preclinical development.

A potent peptide-steroid conjugate accumulates in cartilage and reverses arthritis without evidence of systemic corticosteroid exposure.

On-target, off-tissue toxicity limits the systemic use of drugs that would otherwise reduce symptoms or reverse the damage of arthritic diseases, leaving millions of patients in pain and with limited physical mobility. We identified cystine-dense peptides (CDPs) that rapidly accumulate in cartilage of the knees, ankles, hips, shoulders, and intervertebral discs after systemic administration. These CDPs could be used to concentrate arthritis drugs in joints. A cartilage-accumulating peptide, CDP-11R, reached peak concentration in cartilage within 30 min after administration and remained detectable for more than 4 days. Structural analysis of the peptides by crystallography revealed that the distribution of positive charge may be a distinguishing feature of joint-accumulating CDPs. In addition, quantitative whole-body autoradiography showed that the disulfide-bonded tertiary structure is critical for cartilage accumulation and retention. CDP-11R distributed to joints while carrying a fluorophore imaging agent or one of two different steroid payloads, dexamethasone (dex) and triamcinolone acetonide (TAA). Of the two payloads, the dex conjugate did not advance because the free drug released into circulation was sufficient to cause on-target toxicity. In contrast, the CDP-11R-TAA conjugate alleviated joint inflammation in the rat collagen-induced model of rheumatoid arthritis while avoiding toxicities that occurred with nontargeted steroid treatment at the same molar dose. This conjugate shows promise for clinical development and establishes proof of concept for multijoint targeting of disease-modifying therapeutic payloads.

Use of Letermovir as Salvage Therapy for Drug-Resistant Cytomegalovirus Retinitis.

Treatment options for drug-resistant cytomegalovirus (CMV) are limited. Letermovir is a novel antiviral recently approved for CMV prophylaxis following hematopoietic cell transplantation, but its efficacy in other settings is unknown. We recently used letermovir for salvage treatment in four solid organ transplant recipients with ganciclovir-resistant CMV retinitis. All patients improved clinically without known adverse drug events. However, three patients failed to maintain virologic suppression, including two patients who developed genotypically confirmed resistance to letermovir while on therapy.

A biobank of patient-derived pediatric brain tumor models.

Brain tumors are the leading cause of cancer-related death in children. Genomic studies have provided insights into molecular subgroups and oncogenic drivers of pediatric brain tumors that may lead to novel therapeutic strategies. To evaluate new treatments, better preclinical models adequately reflecting the biological heterogeneity are needed. Through the Children's Oncology Group ACNS02B3 study, we have generated and comprehensively characterized 30 patient-derived orthotopic xenograft models and seven cell lines representing 14 molecular subgroups of pediatric brain tumors. Patient-derived orthotopic xenograft models were found to be representative of the human tumors they were derived from in terms of histology, immunohistochemistry, gene expression, DNA methylation, copy number, and mutational profiles. In vivo drug sensitivity of targeted therapeutics was associated with distinct molecular tumor subgroups and specific genetic alterations. These models and their molecular characterization provide an unprecedented resource for the cancer community to study key oncogenic drivers and to evaluate novel treatment strategies.

Canthal cutdown for emergent treatment of orbital compartment syndrome.

This article evaluates the use of a "canthal cutdown" technique in orbital compartment syndrome in a cadaveric model. Twelve cadaver orbits were used to simulate orbital compartment syndrome using a blood analog solution. Two pressure probes, in different orbital locations, were used to monitor orbital pressure. Pressure was monitored during successive procedures: canthotomy, cantholysis, and canthal cutdown. Orbits were then re-injected with solution, simulating an active orbital hemorrhage, and pressure measurements were recorded over a 10-minute duration. No statistically significant difference was found between the two orbital pressure monitoring devices at each measurement point (p = 0.99). Significant pressure reductions, for both probes, were observed after canthal cutdown compared to initial measurement after injection of 20 mL blood analog (p < 0.001 and p = 0.005). When comparing the orbital pressure following canthotomy and inferior cantholysis versus canthal cutdown, the cutdown procedure provided an additional 74% in orbital pressure reduction (p =0.01). After re-injection of 10 mL of solution and 10 minutes of egress, pressure returned to baseline (probe 1: baseline 7 mm Hg vs. post-cutdown at 10 minutes 7 mm Hg; p = 0.83; and probe 2: 5 mm Hg vs. 5 mm Hg; p = 0.83). The canthal cutdown technique provides further reduction in orbital pressure versus canthotomy and cantholysis alone. The technique may be effective for treatment of static orbital compartment syndrome and temporizing treatment of compartment syndrome from active orbital hemorrhages.

African Tick Bite Fever Treated Successfully With Rifampin in a Patient With Doxycycline Intolerance.

African tick bite fever is the most commonly encountered travel-associated rickettsiosis, occurring in as many as 5% of travelers returning from rural subequatorial Africa. This case report illustrates that rifampin represents an effective alternative to doxycycline for treatment of African tick bite fever in some selective situations.

Diagnosis of Capnocytophaga canimorsus Sepsis by Whole-Genome Next-Generation Sequencing.

We report the case of a 60-year-old man with septic shock due to Capnocytophaga canimorsus that was diagnosed in 24 hours by a novel whole-genome next-generation sequencing assay. This technology shows great promise in identifying fastidious pathogens, and, if validated, it has profound implications for infectious disease diagnosis.

A technology platform to assess multiple cancer agents simultaneously within a patient's tumor.

A fundamental problem in cancer drug development is that antitumor efficacy in preclinical cancer models does not translate faithfully to patient outcomes. Much of early cancer drug discovery is performed under in vitro conditions in cell-based models that poorly represent actual malignancies. To address this inconsistency, we have developed a technology platform called CIVO, which enables simultaneous assessment of up to eight drugs or drug combinations within a single solid tumor in vivo. The platform is currently designed for use in animal models of cancer and patients with superficial tumors but can be modified for investigation of deeper-seated malignancies. In xenograft lymphoma models, CIVO microinjection of well-characterized anticancer agents (vincristine, doxorubicin, mafosfamide, and prednisolone) induced spatially defined cellular changes around sites of drug exposure, specific to the known mechanisms of action of each drug. The observed localized responses predicted responses to systemically delivered drugs in animals. In pair-matched lymphoma models, CIVO correctly demonstrated tumor resistance to doxorubicin and vincristine and an unexpected enhanced sensitivity to mafosfamide in multidrug-resistant lymphomas compared with chemotherapy-naïve lymphomas. A CIVO-enabled in vivo screen of 97 approved oncology agents revealed a novel mTOR (mammalian target of rapamycin) pathway inhibitor that exhibits significantly increased tumor-killing activity in the drug-resistant setting compared with chemotherapy-naïve tumors. Finally, feasibility studies to assess the use of CIVO in human and canine patients demonstrated that microinjection of drugs is toxicity-sparing while inducing robust, easily tracked, drug-specific responses in autochthonous tumors, setting the stage for further application of this technology in clinical trials.

Distinct neuroinflammatory profile in post-mortem human Huntington's disease.

Neuroinflammation is a prominent feature of many neurodegenerative diseases, however, little is known about neuroinflammation in Huntington's disease. We used quantitative real time-PCR to compare the expression level of neuroinflammation-associated mediators in the striatum, cortex, and cerebellum from post-mortem Huntington's disease patient samples with controls. We found increased expression of several key inflammatory mediators, including CCL2 and IL-10, specifically in the striatum of Huntington's disease patients, the main area affected by this pathology. Remarkably, we also found upregulation of IL-6, IL-8, and MMP9, in the cortex and notably the cerebellum, a brain area commonly thought to be spared by Huntington's disease. Our data suggest that neuroinflammation is a prominent feature associated with Huntington's disease and may constitute a novel target for therapeutic intervention.

A large number of protein expression changes occur early in life and precede phenotype onset in a mouse model for huntington disease.

Huntington disease (HD) is fatal in humans within 15-20 years of symptomatic disease. Although late stage HD has been studied extensively, protein expression changes that occur at the early stages of disease and during disease progression have not been reported. In this study, we used a large two-dimensional gel/mass spectrometry-based proteomics approach to investigate HD-induced protein expression alterations and their kinetics at very early stages and during the course of disease. The murine HD model R6/2 was investigated at 2, 4, 6, 8, and 12 weeks of age, corresponding to absence of disease and early, intermediate, and late stage HD. Unexpectedly the most HD stage-specific protein changes (71-100%) as well as a drastic alteration (almost 6% of the proteome) in protein expression occurred already as early as 2 weeks of age. Early changes included mainly the up-regulation of proteins involved in glycolysis/gluconeogenesis and the down-regulation of the actin cytoskeleton. This suggests a period of highly variable protein expression that precedes the onset of HD phenotypes. Although an up-regulation of glycolysis/gluconeogenesis-related protein alterations remained dominant during HD progression, late stage alterations at 12 weeks showed an up-regulation of proteins involved in proteasomal function. The early changes in HD coincide with a peak in protein alteration during normal mouse development at 2 weeks of age that may be responsible for these massive changes. Protein and mRNA data sets showed a large overlap on the level of affected pathways but not single proteins/mRNAs. Our observations suggest that HD is characterized by a highly dynamic disease pathology not represented by linear protein concentration alterations over the course of disease.

Brain-specific proteins decline in the cerebrospinal fluid of humans with Huntington disease.

We integrated five sets of proteomics data profiling the constituents of cerebrospinal fluid (CSF) derived from Huntington disease (HD)-affected and -unaffected individuals with genomics data profiling various human and mouse tissues, including the human HD brain. Based on an integrated analysis, we found that brain-specific proteins are 1.8 times more likely to be observed in CSF than in plasma, that brain-specific proteins tend to decrease in HD CSF compared with unaffected CSF, and that 81% of brain-specific proteins have quantitative changes concordant with transcriptional changes identified in different regions of HD brain. The proteins found to increase in HD CSF tend to be liver-associated. These protein changes are consistent with neurodegeneration, microgliosis, and astrocytosis known to occur in HD. We also discuss concordance between laboratories and find that ratios of individual proteins can vary greatly, but the overall trends with respect to brain or liver specificity were consistent. Concordance is highest between the two laboratories observing the largest numbers of proteins.

Flame etching enhances the sensitivity of carbon-fiber microelectrodes.

Small sensors are useful for in vivo measurements and probing small spaces. In this paper, we compare two methods of fabrication of small, cylindrical carbon-fiber microelectrodes: flame-etching and electrochemical etching. With both methods, microelectrodes can be fabricated with tip diameters of 1 to 3 microm. Electrodes were tested with fast-scan cyclic voltammetry. Flame etching resulted in electrodes that have larger S/N ratios and higher currents per unit area for 1 microM dopamine than normal carbon-fiber microelectrodes or electrochemically etched electrodes. Therefore, the increased sensitivity is not just a property of size. The flame-etched surfaces had nanometer-scale surface features that were not observed on the other electrodes and exhibited increased sensitivity for other electroactive compounds found in the brain, including ascorbic acid, DOPAC, and serotonin. Faster kinetics and a faster response to a step change in dopamine were also observed, when the applied waveform was -0.4 to 1.0 V and back at 400 V/s. The sensitivity of the flame-etched electrodes was enhanced by overoxidizing the surface. The flame-etched electrodes were used to detect dopamine release in anesthetized rats after a single stimulation pulse. The small flame-etched electrodes will facilitate measurements of low concentrations in discrete brain regions or small organisms.

Expression profiling of Huntington's disease models suggests that brain-derived neurotrophic factor depletion plays a major role in striatal degeneration.

Many pathways have been proposed as contributing to Huntington's disease (HD) pathogenesis, but generally the in vivo effects of their perturbation have not been compared with reference data from human patients. Here we examine how accurately mechanistically motivated and genetic HD models recapitulate the striatal gene expression phenotype of human HD. The representative genetic model was the R6/2 transgenic mouse, which expresses a fragment of the huntingtin protein containing a long CAG repeat. Pathogenic mechanisms examined include mitochondrial dysfunction; profiled in 3-nitropropionic acid-treated rats, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice, and PGC-1alpha knock-out mice; and depletion of brain-derived neurotrophic factor (BDNF) using heterozygous and forebrain-specific BDNF-knock-out mice (BDNF(HET), Emx-BDNF(KO)). Based on striatal gene expression, we find the BDNF models, both heterozygous and homozygous knock-outs, to be more like human HD than the other HD models. This implicates reduced trophic support as a major pathway contributing to striatal degeneration in HD. Because the majority of striatal BDNF is synthesized by cortical neurons, the data also imply that cortical dysfunction contributes to HD's hallmark effects on the basal ganglia. Finally, the results suggest that striatal lesions caused by mitochondrial toxins may arise via pathways different from those that drive neurodegeneration in HD. Based on these findings, we present a testable model of HD pathogenesis that, unlike most models, begins to account for regional specificity in human HD and the absence of such specificity in genetic mouse models of HD.

Huntingtin interacting proteins are genetic modifiers of neurodegeneration.

Huntington's disease (HD) is a fatal neurodegenerative condition caused by expansion of the polyglutamine tract in the huntingtin (Htt) protein. Neuronal toxicity in HD is thought to be, at least in part, a consequence of protein interactions involving mutant Htt. We therefore hypothesized that genetic modifiers of HD neurodegeneration should be enriched among Htt protein interactors. To test this idea, we identified a comprehensive set of Htt interactors using two complementary approaches: high-throughput yeast two-hybrid screening and affinity pull down followed by mass spectrometry. This effort led to the identification of 234 high-confidence Htt-associated proteins, 104 of which were found with the yeast method and 130 with the pull downs. We then tested an arbitrary set of 60 genes encoding interacting proteins for their ability to behave as genetic modifiers of neurodegeneration in a Drosophila model of HD. This high-content validation assay showed that 27 of 60 orthologs tested were high-confidence genetic modifiers, as modification was observed with more than one allele. The 45% hit rate for genetic modifiers seen among the interactors is an order of magnitude higher than the 1%-4% typically observed in unbiased genetic screens. Genetic modifiers were similarly represented among proteins discovered using yeast two-hybrid and pull-down/mass spectrometry methods, supporting the notion that these complementary technologies are equally useful in identifying biologically relevant proteins. Interacting proteins confirmed as modifiers of the neurodegeneration phenotype represent a diverse array of biological functions, including synaptic transmission, cytoskeletal organization, signal transduction, and transcription. Among the modifiers were 17 loss-of-function suppressors of neurodegeneration, which can be considered potential targets for therapeutic intervention. Finally, we show that seven interacting proteins from among 11 tested were able to co-immunoprecipitate with full-length Htt from mouse brain. These studies demonstrate that high-throughput screening for protein interactions combined with genetic validation in a model organism is a powerful approach for identifying novel candidate modifiers of polyglutamine toxicity.