Publications by authors named "Joseph Merriman"

The skin microbiome plays a pivotal role in the production of attractive cues detected by mosquitoes. Here, we leveraged recent advances in genetic engineering to significantly reduce the production of L-(+)-lactic acid as a strategy to reduce mosquito attraction to the highly prominent skin commensals and Engraftment of these engineered bacteria onto the skin of mice reduced mosquito attraction and feeding for up to 11 uninterrupted days, which is considerably longer than the several hours of protection conferred by the leading chemical repellent N,N-diethyl-meta-toluamide. Taken together, our findings demonstrate engineering the skin microbiome to reduce attractive volatiles represents an innovative untapped strategy to reduce vector attraction, preventing bites, and pathogen transmission.

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The resident human skin microbiome is responsible for the production of most of the human scents that are attractive to mosquitoes. Hence, engineering the human skin microbiome to synthesize less of mosquito attractants or produce repellents could potentially reduce bites and prevent the transmission of deadly mosquito-borne pathogens. In order to further characterize the human skin volatilome, we quantified the major volatiles of 39 strains of skin commensals (Staphylococci and Corynebacterium).

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Unlabelled: The skin microbiome plays a pivotal role in the production of attractive cues detected by mosquitoes. Here we leveraged recent advances in genetic engineering to significantly reduce the production of L-(+)-lactic acid as a strategy to reduce mosquito attraction to the highly prominent skin commensals and . Engraftment of these engineered bacteria onto the skin of mice reduced mosquito attraction and feeding for up to 11 uninterrupted days, which is considerably longer than the several hours of protection conferred by the leading chemical repellent DEET.

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Sore throat is one of the most common complaints encountered in the ambulatory clinical setting. Rapid, culture-independent diagnostic techniques that do not rely on pharyngeal swabs would be highly valuable as a point-of-care strategy to guide outpatient antibiotic treatment. Despite the promise of this approach, efforts to detect volatiles during oropharyngeal infection have yet been limited.

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The resident human skin microbiome is responsible for the production of most of the human scents that are attractive to mosquitoes. Hence, engineering the human skin microbiome to synthesize less of mosquito attractants or produce repellents could potentially reduce bites and prevent the transmission of deadly mosquito-borne pathogens. In order to further characterize the human skin volatilome, we quantified the major volatiles of 39 strains of skin commensals ( and ).

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Microbial pathogens balance growth against tissue damage to achieve maximum fitness. Central carbon metabolism is connected to growth, but how it influences growth/damage balance is largely unknown. Here we examined how carbon flux through the exclusively fermentative metabolism of the pathogenic lactic acid bacterium Streptococcus pyogenes impacts patterns of growth and tissue damage.

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Antibiotic-resistant bacteria in the genus Enterococcus are a major cause of nosocomial infections and are an emergent public health concern. Similar to a number of bacterial species, resistance to the antibiotic rifampicin (Rif) in enterococci is associated with mutations in the gene encoding the β subunit of RNA polymerase (rpoB). In Mycobacterium tuberculosis, RifrpoB mutations alter mycobacterial surface lipid expression and are associated with an altered IL-1 cytokine response in macrophages upon infection.

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Article Synopsis
  • Breast cancer is the most prevalent cancer among women and second in cancer mortality; however, many eligible women in the U.S. are not receiving personalized screening or chemoprevention, as primary care providers lack awareness of assessment models.
  • An online survey targeting Veterans Health Administration providers in various medical fields sought to evaluate their comfort, knowledge, and practice regarding breast cancer risk assessment and chemoprevention methods.
  • Results revealed that only a small percentage of providers frequently used risk models or prescribed chemoprevention, with identified barriers including a lack of education and limited provider time; efforts are needed to enhance education and identification of high-risk women.
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  • The treatment for metastatic renal cell carcinoma (mRCC) is evolving and currently includes a mix of therapies, leading to the need for genomic markers to predict patient responses to these treatments.* -
  • This study analyzed tumor tissue from 79 mRCC patients, using targeted sequencing to identify genetic alterations and correlate them with progression-free survival (PFS) on VEGF targeted therapy.* -
  • Results indicated that the absence of VHL mutations, along with specific alterations in TP53 and FLT1, is linked to poorer PFS, suggesting a composite model of these genomic markers could help better predict treatment outcomes.*
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The small intestine contains CD4CD8αα double-positive intraepithelial lymphocytes (DP IELs), which originate from intestinal CD4 T cells through down-regulation of the transcription factor Thpok and have regulatory functions. DP IELs are absent in germ-free mice, which suggests that their differentiation depends on microbial factors. We found that DP IEL numbers in mice varied in different vivaria, correlating with the presence of This species induced DP IELs in germ-free mice and conventionally-raised mice lacking these cells.

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Purpose Hand-foot syndrome is a common dose limiting toxicity of vascular endothelial growth factor receptor tyrosine kinase inhibitors used for treatment of patients with metastatic renal cell carcinoma. The effect of treatment dose reductions, in the context of hand-foot syndrome, on survival outcomes is reported. Methods This was a retrospective case series of patients receiving vascular endothelial growth factor receptor tyrosine kinase inhibitors from 1 January 2004 to 31 October 2013.

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Background: Immunotherapy with high-dose interleukin-2 (HD-IL2) results in long-term survival in some metastatic renal cell carcinoma (mRCC) patients but has significant acute toxicities. Biomarkers predicting response to therapy are needed to better select patients most likely to benefit. NLR (absolute neutrophil count (ANC)/absolute lymphocyte count (ALC)) is a prognostic and predicative biomarker in various malignancies.

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Atopic dermatitis (AD) is an inflammatory skin condition strongly associated with colonization and infection. strains shift in populations in ~10-year intervals depending on virulence factors. Shifts in virulence factors may in part explain the racial differences observed in the levels of prevalence and severity of AD.

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Conditional survival (CS) is a clinically useful prediction measure which adjusts a patient's prognosis based on their duration of survival since initiation of therapy. CS has been described in numerous malignancies, and recently described in patients with metastatic renal cell carcinoma (mRCC) who received vascular endothelial growth factor tyrosine kinase inhibitor (VEGFTKI) therapy. However, CS has been not reported in the context of mRCC treated with high-dose interleukin-2 therapy (HDIL-2).

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Purpose: In metastatic renal cell carcinoma (mRCC), survival benefit associated with objective response rates of 16-20 % with high-dose interleukin-2 (HDIL-2) is well established and discussed. Based on recently emerged data on efficacy of cancer immunotherapy, we hypothesized that the survival benefit with HDIL-2 extends beyond those achieving objective responses, i.e.

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Staphylococcus aureus is a human commensal and opportunistic pathogen that causes devastating infections in a wide range of locations within the body. One of the defining characteristics of S. aureus is its ability to form clumps in the presence of soluble fibrinogen, which likely has a protective benefit and facilitates adhesion to host tissue.

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Background: Superantigens are indispensable virulence factors for Staphylococcus aureus in disease causation. Superantigens stimulate massive immune cell activation, leading to toxic shock syndrome (TSS) and contributing to other illnesses. However, superantigens differ in their capacities to induce body-wide effects.

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β-Toxin is an important virulence factor of Staphylococcus aureus, contributing to colonization and development of disease [Salgado-Pabon, W., et al. (2014) J.

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This is a report of chromophobe renal cell carcinoma (ChRCC), a rare entity that accounts for 6% to 11% of cases of renal cell carcinoma (RCC). ChRCC is considered to yield a good prognosis as it typically presents as an early stage tumor with longer overall survival when compared with clear cell RCC; however, metastatic disease negates this survival difference and is characterized by poor prognosis. The available clinical investigations supporting the guidelines for treatment of metastatic RCC are predominantly based on clear cell RCC studies.

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Purifying natively produced staphylococcal superantigens is an important process in the study of these proteins, as many common methods of protein purification are affected by staphylococcal protein A contamination. Here, we describe a proven approach for identifying superantigens in vitro as well as for purifying novel superantigens both in His-tagged and native forms using modern genetic tools coupled with thin-layer isoelectric focusing.

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The 1928 Bundaberg disaster is one of the greatest vaccine tragedies in history. Of 21 children immunized with a diphtheria toxin-antitoxin preparation contaminated with Staphylococcus aureus, 18 developed life-threatening disease and 12 died within 48  h. Historically, the deaths have been attributed to α-toxin, a secreted cytotoxin produced by most S.

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Staphylococcus aureus is a leading cause of surgical site infections that results in increased hospital stays due to the development of chronic wounds. Little is known about factors involved in S. aureus' ability to prevent wounds from healing.

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