Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 143
Filter
1.
JID Innov ; 4(4): 100286, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38994234

ABSTRACT

Basal cell carcinoma (BCC) is classified histologically into subtypes that determine treatment decisions. MicroRNAs (miRs) are short noncoding RNAs that may serve as diagnostic biomarkers. We investigated if particular miRs could distinguish BCC subtypes. We sequenced miRs from 55 archival BCC and 9 control skin specimens and then validated these miRs by qRT-PCR assay on a second BCC cohort (18 superficial, 16 nodular, 15 infiltrative) and control skin (n = 12). Expression values for individual miRs were normalized to miR-16-5p, which was the least variant among the control skin and BCC samples. We found that (i) miR-383-5p and miR-145-5p are downregulated in all BCC subtypes compared with control skin, (ii) miR-181c-5p is downregulated in superficial compared with invasive (nodular/infiltrative) BCC, and (iii) miR-22-5p and miR-708-5p are upregulated in infiltrative compared with superficial/nodular BCC and miR-30c-5p is downregulated in infiltrative compared with nodular BCC. Receiver operating characteristic analysis demonstrated excellent capacity of these miRs to discriminate between BCC and control skin (area under the curve, 0.94-0.98), whereas the capacity to discriminate between superficial and invasive subtypes was less robust (area under the curve, 0.7-0.8). Future prospective studies may determine the utility of these miRs as diagnostic biomarkers to guide biopsy and treatment of BCC.

2.
bioRxiv ; 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38948879

ABSTRACT

Acral melanoma (AM) is an aggressive melanoma variant that arises from palmar, plantar, and nail unit melanocytes. Compared to non-acral cutaneous melanoma (CM), AM is biologically distinct, has an equal incidence across genetic ancestries, typically presents in advanced stage disease, is less responsive to therapy, and has an overall worse prognosis. Independent analysis of published genomic and transcriptomic sequencing identified that receptor tyrosine kinase (RTK) ligands and adapter proteins are frequently amplified, translocated, and/or overexpressed in AM. To target these unique genetic changes, a zebrafish acral melanoma model was exposed to a panel of narrow and broad spectrum multi-RTK inhibitors, revealing that dual FGFR/VEGFR inhibitors decrease acral-analogous melanocyte proliferation and migration. The potent pan-FGFR/VEGFR inhibitor, Lenvatinib, uniformly induces tumor regression in AM patient-derived xenograft (PDX) tumors but only slows tumor growth in CM models. Unlike other multi-RTK inhibitors, Lenvatinib is not directly cytotoxic to dissociated AM PDX tumor cells and instead disrupts tumor architecture and vascular networks. Considering the great difficulty in establishing AM cell culture lines, these findings suggest that AM may be more sensitive to microenvironment perturbations than CM. In conclusion, dual FGFR/VEGFR inhibition may be a viable therapeutic strategy that targets the unique biology of AM.

5.
JAMA Dermatol ; 159(3): 335-336, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36753235

ABSTRACT

A woman in her 30s presents with a bruise on her hand with a blue-green plaque that appeared after a twisting injury to the affected hand. What is your diagnosis?


Subject(s)
Skin Abnormalities , Skin Diseases , Female , Humans
7.
Case Rep Dermatol Med ; 2022: 2598965, 2022.
Article in English | MEDLINE | ID: mdl-36386569

ABSTRACT

This study describes a case of amelanotic lentigo maligna melanoma in a 69-year-old female that had been growing for approximately 5 years. The asymptomatic lesion had been previously diagnosed and treated as a fungal skin infection, an inflammatory rash, and an actinic keratosis that did not respond to standard treatments. Biopsy revealed confluent and nested atypical melanocytes at the dermal-epidermal junction, consistent with melanoma in situ. Excisional biopsy revealed invasive lentigo maligna melanoma, Breslow depth 0.3 mm, with positive melanoma in situ at margins. She is now 3 years post-Mohs surgery without recurrence. When working up a patient with a hypopigmented or inflammatory lesion not responding to standard therapies, physicians should always consider biopsy to rule out unusual neoplastic etiologies, such as amelanotic melanomas.

8.
Int J Food Microbiol ; 370: 109638, 2022 Jun 02.
Article in English | MEDLINE | ID: mdl-35378381

ABSTRACT

Thermal inactivation of pathogenic and spoilage organisms in low and intermediate moisture foods is of critical importance for guaranteeing microbiological safety and stability of these products. Producers tendentially reduce salt in low and intermediate moisture foods because of nutritional health considerations, but it is unclear how this affects microbial inactivation rates during pasteurization. In this study we predict the time to achieve a pre-defined 6-log reduction for Salmonella enterica subsp. enterica serovar Napoli (hereafter: S. Napoli) and Eurotium herbariorum mould spores (hereafter: E. herbariorum spores) and the relationship with product characteristics. We tested 31 design products for heat inactivation of S. Napoli and 29 design products for heat inactivation of E. herbariorum spores. We used a global Bayesian regression combining primary Weibull models with a secondary regression model to relate pasteurization temperature and product characteristics (water activity (aw), pH, and fractions of sodium chloride, sucrose and oil on product) to microbial counts. With this model, we predict the time to 6-log reduction. Thermal inactivation rates were much higher for vegetative S. Napoli than for E. herbariorum spores. Also, inactivation curves were non-linear for many experiments. There were significant associations between the Weibull model parameters and temperature, and pH and aw for S. Napoli and E. herbariorum spores, respectively. We parameterized an inactivation model for S. Napoli and E. herbariorum spores using design products with a broad range of characteristics and showed how the simplified approach of using D-values does not accurately describe the non-linearity of thermal inactivation for both types of organism. Results of our model can be used to produce accurate heat inactivation predictions as input for the pasteurization process in factories where intermediate moisture foods are manufactured.


Subject(s)
Food Microbiology , Hot Temperature , Aspergillus , Bayes Theorem , Colony Count, Microbial , Salmonella/physiology , Spores, Fungal
9.
Front Med (Lausanne) ; 8: 642380, 2021.
Article in English | MEDLINE | ID: mdl-33937286

ABSTRACT

Despite significant progress in the development of treatment options, melanoma remains a leading cause of death due to skin cancer. Advances in our understanding of the genetic, transcriptomic, and morphologic spectrum of benign and malignant melanocytic neoplasia have enabled the field to propose biomarkers with potential diagnostic, prognostic, and predictive value. While these proposed biomarkers have the potential to improve clinical decision making at multiple critical intervention points, most remain unvalidated. Clinical validation of even the most commonly assessed biomarkers will require substantial resources, including limited clinical specimens. It is therefore important to consider the properties that constitute a relevant and clinically-useful biomarker-based test prior to engaging in large validation studies. In this review article we adapt an established framework for determining minimally-useful biomarker test characteristics, and apply this framework to a discussion of currently used and proposed biomarkers designed to aid melanoma detection, staging, prognosis, and choice of treatment.

10.
J Pediatr Surg ; 56(2): 239-244, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32829881

ABSTRACT

PURPOSE: Assessing quality of life (QoL) after esophageal replacement (ER) for long gap esophageal atresia (LGEA). METHODS: All patients after ER for LGEA with gastric pull-up (GPU n = 9) or jejunum interposition (JI n = 14) at the University Medical Center Groningen and Utrecht (1985-2007) were included. QoL was assessed with 1) gastrointestinal-related QoL using the Gastrointestinal Quality of Life Index (GIQLI)), 2) general QoL (Child Health questionnaire CHF87-BREF (children)/World Health Organization questionnaire WHOQOL-BREF (adults)), and 3) health-related QoL (HRQoL) (TNO AZL TACQoL/TAAQoL). Association of morbidity (heartburn, dysphagia, dyspnea on exertion, recurrent cough) and (HR)QoL was evaluated. RESULTS: Six patients after GPU (75%) and eight patients after JI (57%) responded to the questionnaires (mean age 15.7, SD 5.9, 12 male, two female). Mean gastrointestinal, general and health-related QoL total scores of the patients were comparable to healthy controls. However, young adults reported a worse physical functioning (p = 0.02) but better social functioning compared to peers (p = 0.01). Morbidity was not associated with significant differences in (HR)QoL. CONCLUSIONS: With the current validated QoL most patients after ER with GPU and JI for LGEA have normal generic and disease specific QoL scores. Postoperative morbidity does not seem to influence (HR)QoL. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: III.


Subject(s)
Esophageal Atresia , Esophagoplasty , Adolescent , Anastomosis, Surgical , Child , Esophageal Atresia/surgery , Female , Humans , Male , Quality of Life , Surveys and Questionnaires , Young Adult
12.
JAMA Dermatol ; 156(9): 1004-1011, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32725204

ABSTRACT

Importance: Use of prognostic gene expression profile (GEP) testing in cutaneous melanoma (CM) is rising despite a lack of endorsement as standard of care. Objective: To develop guidelines within the national Melanoma Prevention Working Group (MPWG) on integration of GEP testing into the management of patients with CM, including (1) review of published data using GEP tests, (2) definition of acceptable performance criteria, (3) current recommendations for use of GEP testing in clinical practice, and (4) considerations for future studies. Evidence Review: The MPWG members and other international melanoma specialists participated in 2 online surveys and then convened a summit meeting. Published data and meeting abstracts from 2015 to 2019 were reviewed. Findings: The MPWG members are optimistic about the future use of prognostic GEP testing to improve risk stratification and enhance clinical decision-making but acknowledge that current utility is limited by test performance in patients with stage I disease. Published studies of GEP testing have not evaluated results in the context of all relevant clinicopathologic factors or as predictors of regional nodal metastasis to replace sentinel lymph node biopsy (SLNB). The performance of GEP tests has generally been reported for small groups of patients representing particular tumor stages or in aggregate form, such that stage-specific performance cannot be ascertained, and without survival outcomes compared with data from the American Joint Committee on Cancer 8th edition melanoma staging system international database. There are significant challenges to performing clinical trials incorporating GEP testing with SLNB and adjuvant therapy. The MPWG members favor conducting retrospective studies that evaluate multiple GEP testing platforms on fully annotated archived samples before embarking on costly prospective studies and recommend avoiding routine use of GEP testing to direct patient management until prospective studies support their clinical utility. Conclusions and Relevance: More evidence is needed to support using GEP testing to inform recommendations regarding SLNB, intensity of follow-up or imaging surveillance, and postoperative adjuvant therapy. The MPWG recommends further research to assess the validity and clinical applicability of existing and emerging GEP tests. Decisions on performing GEP testing and patient management based on these results should only be made in the context of discussion of testing limitations with the patient or within a multidisciplinary group.


Subject(s)
Clinical Decision-Making/methods , Gene Expression Profiling/standards , Melanoma/diagnosis , Practice Guidelines as Topic , Skin Neoplasms/diagnosis , Consensus , Consensus Development Conferences as Topic , Humans , Melanoma/genetics , Melanoma/pathology , Melanoma/therapy , Neoplasm Staging , Prognosis , Sentinel Lymph Node Biopsy/standards , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Skin Neoplasms/therapy
13.
BMC Health Serv Res ; 20(1): 213, 2020 Mar 14.
Article in English | MEDLINE | ID: mdl-32171308

ABSTRACT

BACKGROUND: For studying the effectiveness of treatment, it is important to check whether a new treatment is performed as originally described in the study-protocol. OBJECTIVES: To evaluate whether an interdisciplinary graded exposure program, for adolescents with chronic musculoskeletal pain reporting pain-related fear, was performed according to protocol, and whether it is feasible to implement the program in rehabilitation care. METHODS: A process evaluation where quantitative and qualitative data on participant characteristics (adolescents, parents and therapists), attendance and participants' opinion on the program were collected, by means of registration forms, questionnaires and group interviews. To evaluate treatment fidelity, audio and video recordings of program sessions were analyzed. RESULTS: Thirty adolescents were offered the program, of which 23 started the program. Adolescents attended on average 90% of the sessions. At least one parent per adolescent participated in the program. Analysis of 20 randomly selected recordings of treatment sessions revealed that treatment fidelity was high, since 81% of essential treatment elements were offered to the adolescents. The program was considered client-centered by adolescents and family-centered by parents. Treatment teams wished to continue offering the program in their center. CONCLUSION: The interdisciplinary graded exposure program was performed largely according to protocol, and therapists, adolescents and their parents had a favorable opinion on the program. Implementation of the program in rehabilitation care is considered feasible. TRIAL REGISTRATION: Clinicaltrials.gov ID: NCT02181725 (7 February 2014).


Subject(s)
Chronic Pain/psychology , Chronic Pain/rehabilitation , Fear , Musculoskeletal Pain/psychology , Musculoskeletal Pain/rehabilitation , Adolescent , Child , Feasibility Studies , Female , Humans , Male , Parents/psychology , Process Assessment, Health Care , Program Evaluation , Qualitative Research , Surveys and Questionnaires
15.
Nat Biomed Eng ; 3(2): 147-157, 2019 02.
Article in English | MEDLINE | ID: mdl-30923642

ABSTRACT

Dilated cardiomyopathy (DCM) is a leading cause of morbidity and mortality worldwide; yet how genetic variation and environmental factors impact DCM heritability remains unclear. Here, we report that compound genetic interactions between DNA sequence variants contribute to the complex heritability of DCM. By using genetic data from a large family with a history of DCM, we discovered that heterozygous sequence variants in the TROPOMYOSIN 1 (TPM1) and VINCULIN (VCL) genes cose-gregate in individuals affected by DCM. In vitro studies of patient-derived and isogenic human-pluripotent-stem-cell-derived cardio-myocytes that were genome-edited via CRISPR to create an allelic series of TPM1 and VCL variants revealed that cardiomyocytes with both TPM1 and VCL variants display reduced contractility and sarcomeres that are less organized. Analyses of mice genetically engineered to harbour these human TPM1 and VCL variants show that stress on the heart may also influence the variable penetrance and expressivity of DCM-associated genetic variants in vivo. We conclude that compound genetic variants can interact combinatorially to induce DCM, particularly when influenced by other disease-provoking stressors.


Subject(s)
Cardiomyopathy, Dilated/genetics , Genetic Predisposition to Disease , Genetic Variation , Animals , Cardiomyopathy, Dilated/physiopathology , Extracellular Matrix/metabolism , Female , Gene Expression Regulation , Humans , Inheritance Patterns/genetics , Male , Mice , Models, Biological , Muscle Contraction/genetics , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Pedigree , Pluripotent Stem Cells/metabolism , Up-Regulation/genetics
16.
Lab Chip ; 19(5): 837-844, 2019 02 26.
Article in English | MEDLINE | ID: mdl-30698187

ABSTRACT

The spread of bacterial resistance against conventional antibiotics generates a great need for the discovery of novel antimicrobials. Polypeptide antibiotics constitute a promising class of antimicrobial agents that favour attack on bacterial membranes. However, efficient measurement platforms for evaluating their mechanisms of action in a systematic manner are lacking. Here we report an integrated lab-on-a-chip multilayer microfluidic platform to quantify the membranolytic efficacy of such antibiotics. The platform is a biomimetic vesicle-based screening assay, which generates giant unilamellar vesicles (GUVs) in physiologically relevant buffers on demand. Hundreds of these GUVs are individually immobilised downstream in physical traps connected to separate perfusion inlets that facilitate controlled antibiotic delivery. Antibiotic efficacy is expressed as a function of the time needed for an encapsulated dye to leak out of the GUVs as a result of antibiotic treatment. This proof-of-principle study probes the dose response of an archetypal polypeptide antibiotic cecropin B on GUVs mimicking bacterial membranes. The results of the study provide a foundation for engineering quantitative, high-throughput microfluidics devices for screening antibiotics.


Subject(s)
Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/pharmacology , Cell Membrane/drug effects , Drug Evaluation, Preclinical/instrumentation , Insect Proteins/analysis , Insect Proteins/pharmacology , Microfluidic Analytical Techniques/instrumentation , Unilamellar Liposomes/chemistry
17.
Stem Cell Reports ; 11(3): 828-841, 2018 09 11.
Article in English | MEDLINE | ID: mdl-30122443

ABSTRACT

To facilitate understanding of human cardiomyocyte (CM) subtype specification, and the study of ventricular CM biology in particular, we developed a broadly applicable strategy for enrichment of ventricular cardiomyocytes (VCMs) derived from human embryonic stem cells (hESCs). A bacterial artificial chromosome transgenic H9 hESC line in which GFP expression was driven by the human ventricular-specific myosin light chain 2 (MYL2) promoter was generated, and screened to identify cell-surface markers specific for MYL2-GFP-expressing VCMs. A CD77+/CD200- cell-surface signature facilitated isolation of >97% cardiac troponin I-positive cells from H9 hESC differentiation cultures, with 65% expressing MYL2-GFP. This study provides a tool for VCM enrichment when using some, but not all, human pluripotent stem cell lines. Tools generated in this study can be utilized toward understanding CM subtype specification, and enriching for VCMs for therapeutic applications.


Subject(s)
Heart Ventricles/cytology , Human Embryonic Stem Cells/cytology , Myocytes, Cardiac/cytology , Antigens, CD/analysis , Cardiac Myosins/analysis , Cell Differentiation , Cell Line , Cells, Cultured , Humans , Myosin Light Chains/analysis , Trihexosylceramides/analysis
18.
Nanoscale ; 9(5): 1862-1870, 2017 Feb 02.
Article in English | MEDLINE | ID: mdl-28094382

ABSTRACT

Nucleosomes form the unit structure of the genome in eukaryotes, thereby constituting a fundamental tenet of chromatin biology. In canonical nucleosomes, DNA wraps around the histone octamer in a left-handed toroidal ramp. Here, in single-molecule magnetic tweezers studies of chaperone-assisted nucleosome assembly, we show that the handedness of the DNA wrapping around the nucleosome core is intrinsically ambidextrous, and depends on the pre-assembly supercoiling state of the DNA, i.e., it is not uniquely determined by the octameric histone core. Nucleosomes assembled onto negatively supercoiled DNA are found to exhibit a left-handed conformation, whereas assembly onto positively supercoiled DNA results in right-handed nucleosomes. This intrinsic flexibility to adopt both chiralities is observed both for canonical H3 nucleosomes, and for centromere-specific variant CENP-A nucleosomes. These data support recent advances suggesting an intrinsic adaptability of the nucleosome, and provide insights into how nucleosomes might rapidly re-assemble after cellular processes that generate positive supercoiling in vivo.


Subject(s)
Centromere Protein A/chemistry , DNA, Superhelical/chemistry , Histones/chemistry , Nucleosomes/chemistry , Centromere
19.
Nanoscale ; 7(32): 13605-9, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26206066

ABSTRACT

Nanopore experiments have traditionally been carried out with chloride-based solutions. Here we introduce silver/silver-glutamate-based electrochemistry as an alternative, and study the viscosity, conductivity, and nanopore translocation characteristics of potassium-, sodium-, and lithium-glutamate solutions. We show that it has a linear response at typical voltages and can be used to detect DNA translocations through a nanopore. The glutamate anion also acts as a redox-capable thickening agent, with high-viscosity solutions capable of slowing down the DNA translocation process by up to 11 times, with a corresponding 7 time reduction in signal. These results demonstrate that glutamate can replace chloride as the primary anion in nanopore resistive pulse sensing.


Subject(s)
DNA/chemistry , DNA/metabolism , Glutamic Acid/chemistry , Glutamic Acid/metabolism , Nanopores , Electric Conductivity , Electrochemical Techniques , Electrodes , Equipment Design , Nanotechnology , Potassium Chloride/chemistry , Viscosity
20.
Stem Cells ; 33(7): 2343-50, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25826782

ABSTRACT

Danon disease is a familial cardiomyopathy associated with impaired autophagy due to mutations in the gene encoding lysosomal-associated membrane protein type 2 (LAMP-2). Emerging evidence has highlighted the importance of autophagy in regulating cardiomyocyte bioenergetics, function, and survival. However, the mechanisms responsible for cellular dysfunction and death in cardiomyocytes with impaired autophagic flux remain unclear. To investigate the molecular mechanisms responsible for Danon disease, we created induced pluripotent stem cells (iPSCs) from two patients with different LAMP-2 mutations. Danon iPSC-derived cardiomyocytes (iPSC-CMs) exhibited impaired autophagic flux and key features of heart failure such as increased cell size, increased expression of natriuretic peptides, and abnormal calcium handling compared to control iPSC-CMs. Additionally, Danon iPSC-CMs demonstrated excessive amounts of mitochondrial oxidative stress and apoptosis. Using the sulfhydryl antioxidant N-acetylcysteine to scavenge free radicals resulted in a significant reduction in apoptotic cell death in Danon iPSC-CMs. In summary, we have modeled Danon disease using human iPSC-CMs from patients with mutations in LAMP-2, allowing us to gain mechanistic insight into the pathogenesis of this disease. We demonstrate that LAMP-2 deficiency leads to an impairment in autophagic flux, which results in excessive oxidative stress, and subsequent cardiomyocyte apoptosis. Scavenging excessive free radicals with antioxidants may be beneficial for patients with Danon disease. In vivo studies will be necessary to validate this new treatment strategy.


Subject(s)
Glycogen Storage Disease Type IIb/genetics , Heart Failure/genetics , Myocytes, Cardiac/metabolism , Oxidative Stress/genetics , Apoptosis , Autophagy , Glycogen Storage Disease Type IIb/pathology , Heart Failure/pathology , Humans , Induced Pluripotent Stem Cells
SELECTION OF CITATIONS
SEARCH DETAIL
...