Citations

ABSTRACTCryptococcus neoformansandCryptococcus gattiiare closely related pathogenic fungi.Cryptococcus neoformansis ecologically widespread and affects primarily immunocompromised patients, whileC. gattiiis traditionally found in tropical climates and has been reported to cause disease in immunocompetent patients.l-Canavanine glycine bromothymol blue (CGB) agar can be used to differentiateC. neoformansandC. gattii, but there are few reports of its performance in routine clinical practice. Growth ofC. gattiion CGB agar produces a blue color, indicating the assimilation of glycine, whileC. neoformansfails to cause a color change. Using reference and clinical strains, we evaluated the ability of CGB agar and D2 large ribosomal subunit DNA sequencing (D2 LSU) to differentiateC. neoformansandC. gattii.One hundred two yeast isolates were screened for urease activity, melanin production, and glycine assimilation on CGB agar as well as by D2 sequencing. Seventeen of 17 (100%)C. gattiiisolates were CGB positive, and 54 of 54C. neoformansisolates were CGB negative. Several yeast isolates other than theC. gattiiisolates were CGB agar positive, indicating that CGB agar cannot be used alone for identification ofC. gattii.D2 correctly identified and differentiated allC. gattiiandC. neoformansisolates. This study demonstrates that the use of CGB agar, in conjunction with urea hydrolysis and Niger seed agar, or D2 LSU sequencing can be reliably used in the clinical laboratory to distinguishC. gattiifromC. neoformans. We describe how CGB agar and D2 sequencing have been incorporated into the yeast identification algorithm in our laboratory.

Abstract Eosinophils (Eos) are found at increased numbers within necrotic areas of tumors. We show that necrotic material from cell lysates containing damage-associated molecular pattern molecules induce eosinophil degranulation (release of major basic protein and eosinophil peroxidase) and enhance their oxidative burst while the stimulatory capacity of cell lysates is significantly diminished following oxidation. High mobility group box 1 (HMGB1), a prototypic damage-associated molecular pattern molecule, released following necrosis but not apoptosis, induced a similar effect on Eos. Additionally, we demonstrate that HMGB1 enhances eosinophil survival and acts as a chemoattractant. Consistently, we show that Eos express an HMGB1 receptor, the receptor for advanced glycation end product, and that anti-receptor for advanced glycation end product could diminish the HMGB1-mediated effects. Of all tested biologic activities, Eos respond most sensitively to the presence of necrotic material including HMGB1 with generation of peroxide. We postulate that Eos “sense” necrotic cell death, migrating to and responding to areas of tissue injury/necrosis. Oxidation of cell lysates reduces their biologic activity when compared with native lysates. We postulate that eosinophil-associated modulation of immunity within tumor and other damaged tissues may be primarily by promoting oxidative degradation of necrotic material. Novel therapeutic strategies may be considered by advancing oxidative denaturation of released necrotic material using Eos or other aerobic strategies.

AbstractBackgroundThe burden of disease, disability, and mortality that could be averted by surgery is growing. However, few low and middle income countries (LMICs) have the infrastructure or capacity to provide surgical services to meet this growing need. Equally, few of these countries have been assessed for key infrastructural capacity including surgical and anesthesia providers, equipment, and supplies. These assessments are critical to revealing magnitude of the evolving surgical and anesthesia workforce crisis, related morbidity and mortality, and necessary steps to mitigate the impact of the crisis.MethodsA pilot Internet‐based survey was conducted to estimate per‐capita anesthesia providers in LMICs. Information was obtained from e‐mail respondents at national health care addresses, and from individuals working in‐country on anesthesia‐related projects.ResultsWorkers from 6 of 98 countries responded to direct e‐mail inquiries, and an additional five responses came from individuals who were working or had worked in‐country at the time of the survey. The data collected revealed that the per‐capita anesthesia provider ratio in the countries surveyed was often 100 times lower than in developed countries.ConclusionsThis pilot study revealed that the number of anesthesia providers available per capita of population is markedly reduced in low and lower middle income countries compared to developed countries. As anesthesia providers are an integral part of the delivery of safe and effective surgical care, it is essential that more data is collected to fully understand the deficiencies in workforce and capacity in low and middle income countries.

Abstract Recent genome-wide association studies have linked the chromosome 15q24-25.1 locus to nicotine addiction and lung cancer susceptibility. To refine the 15q24-25.1 locus, we performed a haplotype-based association analysis of 194 familial lung cases and 219 cancer-free controls from the Genetic Epidemiology of Lung Cancer Consortium (GELCC) collection, and used proliferation and apoptosis analyses to determine which gene(s) in the 15q24-25.1 locus mediates effects on lung cancer cell growth in vitro. We identified two distinct subregions, hapL (P = 3.20 × 10−6) and hapN (P = 1.51 × 10−6), which were significantly associated with familial lung cancer. hapL encompasses IREB2, LOC123688, and PSMA4, and hapN encompasses the three nicotinic acetylcholine receptor subunit genes CHRNA5, CHRNA3, and CHRNB4. Examination of the genes around hapL revealed that PSMA4 plays a role in promoting cancer cell proliferation. PSMA4 mRNA levels were increased in lung tumors compared with normal lung tissues. Down-regulation of PSMA4 expression decreased proteasome activity and induced apoptosis. Proteasome dysfunction leads to many diseases including cancer, and drugs that inhibit proteasome activity show promise as a form of cancer treatment. Genes around hapN were also investigated, but did not show any direct effect on lung cancer cell proliferation. We concluded that PSMA4 is a strong candidate mediator of lung cancer cell growth, and may directly affect lung cancer susceptibility through its modulation of cell proliferation and apoptosis. [Cancer Res 2009;69(19):7844–50]

Abstract ETS variant 1 (ETV1), also known as ETS-related protein 81, is overexpressed in prostate tumors, but whether and how this transcription factor affects tumorigenesis has remained elusive. Here, we show that ETV1 is primarily overexpressed in the most aggressive human prostate tumors. Transgenic ETV1 mice developed prostatic intraepithelial neoplasia as well as hyperplasia/neoplasia in seminal vesicles. Moreover, ETV1 cooperated with the androgen receptor (AR) to bind to the prostate-specific antigen enhancer and stimulate gene transcription. Consistent with its ability to physically interact with AR, ETV1 rendered an ETV1 binding site–driven reporter androgen inducible, and, on the other hand, ETV1 superinduced transcription from an AR binding site on androgen stimulation. In conclusion, our study substantiates that ETV1 overexpression is an underlying cause in the development of prostate and possibly also seminal vesicle cancer. Its interaction with and activation of AR provides a molecular mechanism on how ETV1 exerts its deleterious function. Thus, inhibiting ETV1 or blocking its interaction with AR may represent novel strategies in prostate cancer therapy. [Cancer Res 2009;69(20):8102–10]

Abstract The insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) are receptor tyrosine kinases that participate in mitogenic and antiapoptotic signaling in normal and neoplastic epithelia. In the present study, immunoblotting and reverse transcription-PCR demonstrated expression of IGF1R and IR isoform A in acute myelogenous leukemia (AML) cell lines as well as in >80% of clinical AML isolates. Treatment with insulin enhanced signaling through the Akt and MEK1/2 pathways as well as survival of serum-starved AML cell lines. Conversely, treatment with BMS-536924, a dual IGF1R/IR kinase inhibitor that is undergoing preclinical testing, inhibited constitutive receptor phosphorylation as well as downstream signaling through MEK1/2 and Akt. These changes inhibited proliferation and, in some AML cell lines, induced apoptosis at submicromolar concentrations. Likewise, BMS-536924 inhibited leukemic colony formation in CD34+ clinical AML samples in vitro. Collectively, these results not only indicate that expression of IGF1R and IR isoform A is common in AML but also show that interruption of signaling from these receptors inhibits proliferation in clinical AML isolates. Accordingly, further investigation of IGF1R/IR axis as a potential therapeutic target in AML appears warranted. [Cancer Res 2009;69(19):7635–43]

Oncolytic virotherapy makes use of the natural ability of viruses to infect and kill cancer cells. Adenovirus serotype 5 (Ad5) has been approved for use in humans as a therapy for solid cancers. In this study, we have tested whether Ad5 and low-seroprevalence adenoviruses can be used as oncolytics for multiple myeloma (MM). We show that Ad5 productively infects most myeloma cell lines, replicates to various degrees, and mediates oncolytic cell killing in vitro and in vivo. Comparison of Ad5 with low-seroprevalence Ads on primary marrow samples from MM patients revealed striking differences in the abilities of different adenoviral serotypes to kill normal CD138 – cells and CD138 + MM cells. Ad5 and Ad6 from species C and Ad26 and Ad48 from species D all mediated killing of CD138 + cells with low-level killing of CD138 – cells. In contrast, Ad11, Ad35, Ad40, and Ad41 mediated weak oncolytic effects in all of the cells. Comparison of cell binding, cell entry, and replication revealed that Ad11 and Ad35 bound MM cells 10 to 100 times better than other serotypes. However, after this efficient interaction, Ad11 and Ad35 viral DNA was not replicated and cell killing did not occur. In contrast, Ad5, Ad6, Ad26, and Ad48 all replicated 10- to 100-fold in MM cells and this correlated with cell killing. These data suggest that Ad5 and other low-seroprevalence adenoviruses may have utility as oncolytic agents against MM and other hematologic malignancies.