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1.
Development ; 150(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37882771

RESUMO

During meiosis, germ cell and stage-specific components impose additional layers of regulation on the core cell cycle machinery to set up an extended G2 period termed meiotic prophase. In Drosophila males, meiotic prophase lasts 3.5 days, during which spermatocytes upregulate over 1800 genes and grow 25-fold. Previous work has shown that the cell cycle regulator Cyclin B (CycB) is subject to translational repression in immature spermatocytes, mediated by the RNA-binding protein Rbp4 and its partner Fest. Here, we show that the spermatocyte-specific protein Lut is required for translational repression of cycB in an 8-h window just before spermatocytes are fully mature. In males mutant for rbp4 or lut, spermatocytes enter and exit meiotic division 6-8 h earlier than in wild type. In addition, spermatocyte-specific isoforms of Syncrip (Syp) are required for expression of CycB protein in mature spermatocytes and normal entry into the meiotic divisions. Lut and Syp interact with Fest independent of RNA. Thus, a set of spermatocyte-specific regulators choreograph the timing of expression of CycB protein during male meiotic prophase.


Assuntos
Proteínas de Drosophila , Meiose , Animais , Masculino , Meiose/genética , Espermatogênese/fisiologia , Prófase , Mitose , Espermatócitos/metabolismo , Drosophila/genética , Ciclina B/genética , Ciclina B/metabolismo , Proteínas de Drosophila/metabolismo
2.
Med Humanit ; 50(1): 41-51, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38164581

RESUMO

Scoliosis is an abnormal lateral curvature of the spine with the large majority of cases classed as idiopathic, meaning there is no known cause. Typically, most cases occur in children and young people affecting approximately three per cent of the adult populace with five out of six cases being female. The BackBone: Interdisciplinary Creative Practices and Body Positive Resilience pilot research study used arts and humanities methods to measure the impact of adolescent idiopathic scoliosis (AIS) on well-being and body perception. The research aimed to contribute to a better understanding of alternative treatments towards improving quality of life in young women diagnosed with AIS. In particular, concentrating on two highlighted priorities from the Scoliosis Priority Setting Partnership: (1) How is quality of life affected by scoliosis and its treatment? How can we measure this in ways that are meaningful to patients? (2) How are the psychological impacts (including on body image) of diagnosis and treatment best managed.Using established medical techniques, art-based workshops, and focus groups with postoperative participants with AIS and their families we gathered both quantitative and qualitative data. The workshops explored the aesthetics of imperfection through material investigations that focus on the body as both an object and how it is experienced using the metaphor of tree images. Drawing parallels between the growth patterns of trees that, for complex and often unknown reasons, have grown unexpectedly we explored questions around ideological notions of perfect growth through art-making in a non-clinical setting. Uniquely, the pilot project sought to draw on insights from four key disciplines (art, medicine, psychology and human geography), thinking across boundaries to evoke different ways of knowing and understanding the complexities of body perception through image-making.


Assuntos
Escoliose , Adulto , Criança , Humanos , Adolescente , Feminino , Masculino , Escoliose/psicologia , Escoliose/cirurgia , Qualidade de Vida , Projetos Piloto , Imagem Corporal , Grupos Focais
3.
J Cutan Pathol ; 50(3): 238-242, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36349388

RESUMO

Primary, acute Epstein-Barr virus (EBV) infection is associated with a variety of cutaneous eruptions, including the viral exanthem of infectious mononucleosis and erythema multiforme. Latent, chronic EBV infection can rarely result in development of lymphoproliferative disorders with cutaneous manifestations; however, these disorders do not arise from primary infection. In this report, we present a case of primary, acute EBV infection presenting with histopathologic features closely mimicking aggressive cytotoxic cutaneous T-cell lymphoma.


Assuntos
Infecções por Vírus Epstein-Barr , Exantema , Linfoma Cutâneo de Células T , Transtornos Linfoproliferativos , Neoplasias Cutâneas , Humanos , Infecções por Vírus Epstein-Barr/patologia , Herpesvirus Humano 4 , Transtornos Linfoproliferativos/patologia , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/complicações , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/complicações
4.
J Cutan Pathol ; 50(2): 169-177, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36325821

RESUMO

BACKGROUND: Melanocytic neoplasms can be challenging to diagnose. One well-established diagnostic aid is the detection of copy number variation (CNV) in a few key genetic loci using conventional methods such as fluorescence in situ hybridization (FISH) and chromosomal microarray (CMA). Droplet digital polymerase chain reaction (ddPCR) is a novel, cost-effective, rapid, and automated method to detect CNV. METHODS: We perform the first investigation of ddPCR to assay Ras-responsive element-binding protein-1 (RREB1), the most common CNV in melanoma using formalin-fixed, paraffin-embedded (FFPE) melanocytic lesion samples; CMA data are used as the gold standard. Archival samples from 2013 to 2021 were analyzed, including 153 data points from 39 FFPE samples representing 34 patients. Benign, borderline, malignant, and metastatic melanocytic neoplasms were examined. RESULTS: ddPCR showed a sensitivity and specificity of 93.8% and 95.7% using one reference gene, and 87.5% and 100% using a different reference gene for RREB1 gain detection. CONCLUSIONS: Here we show that ddPCR can provide inexpensive, rapid, and robust data on the commonest copy number alteration in melanoma. Future development and validation could provide a useful ancillary tool in the diagnosis of challenging melanocytic lesions.


Assuntos
Variações do Número de Cópias de DNA , Melanoma , Humanos , Inclusão em Parafina , Hibridização in Situ Fluorescente/métodos , Melanoma/diagnóstico , Melanoma/genética , Reação em Cadeia da Polimerase/métodos , Formaldeído , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética
5.
Am J Dermatopathol ; 45(7): 454-462, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37130203

RESUMO

ABSTRACT: A definitive diagnosis of nevus or melanoma is not always possible for histologically ambiguous melanocytic neoplasms. In such cases, ancillary molecular testing can support a diagnosis of melanoma if certain chromosomal aberrations are detected. Current technologies for copy number variation (CNV) detection include chromosomal microarray analysis (CMA) and fluorescence in situ hybridization. Although CMA and fluorescence in situ hybridization are effective, their utilization can be limited by cost, turnaround time, and inaccessibility outside of large reference laboratories. Droplet digital polymerase chain reaction (ddPCR) is a rapid, automated, and relatively inexpensive technology for CNV detection. We investigated the ability of ddPCR to quantify CNV in cyclin-dependent kinase inhibitor 2A ( CDKN2A ), the most commonly deleted tumor suppressor gene in melanoma. CMA data were used as the gold standard. We analyzed 57 skin samples from 52 patients diagnosed with benign nevi, borderline lesions, primary melanomas, and metastatic melanomas. In a training cohort comprising 29 randomly selected samples, receiver operator characteristic curve analysis revealed an optimal ddPCR cutoff value of 1.73 for calling CDKN2A loss. In a validation cohort comprising the remaining 28 samples, ddPCR detected CDKN2A loss with a sensitivity and specificity of 94% and 90%, respectively. Significantly, ddPCR could also identify whether CDKN2A losses were monoallelic or biallelic. These pilot data suggest that ddPCR can detect CDKN2A deletions in melanocytic tumors with accuracy comparable with CMA. With further validation, ddPCR could provide an additional CNV assay to aid in the diagnosis of challenging melanocytic neoplasms.


Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Humanos , Variações do Número de Cópias de DNA , Genes p16 , Hibridização in Situ Fluorescente/métodos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/patologia , Nevo de Células Epitelioides e Fusiformes/genética , Reação em Cadeia da Polimerase , Inibidor p16 de Quinase Dependente de Ciclina/genética
6.
J Drugs Dermatol ; 20(3): 346-348, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33683087

RESUMO

Topical imiquimod 5% cream has been investigated as off-label primary or adjuvant treatment for melanoma in situ, lentigo maligna type (LM). Herein, we present the largest known case series of lentigo maligna treated with topical imiquimod, with up to 17 years of follow-up, and include a recurrence-free survival analysis. In this case series, 103 lesions were retrospectively evaluated for treatment response and recurrence following a course of topical imiquimod with or without tazarotene gel 0.1% pretreatment between January 1, 2002 and March 31, 2019, and prospectively followed through November 15, 2019. Over median follow-up of 5.1 years (mean = 6.2 years, S = 5.2 years, range, 0.08–17.1 years), including 29.1% LM with >10 years follow-up, we observed a response rate of 97.1% (100/103), with 8 local recurrences (8/100, 8.0%) developing at mean 2.9 years (SD: 2.7 years). Local recurrence was significantly associated with a history of failed excision (P= 0.001), <60 applications of imiquimod (P= 0.04) and partial clinical clearance (P= 0.0003). Recurrence-free survival analysis demonstrated significant risk-stratification for low and high-risk groups (P= 0.0001). Long term risk for recurrence showed significant differences among low- and high-risk cases, with low-risk cases demonstrating favorable long-term outcomes, comparable to conventional and staged surgery. Our observed low recurrence in a large case series with long-term follow-up suggests the efficacy of topical 5% imiquimod for LM and emphasizes the need for randomized control trials comparing imiquimod with, or as an adjunct to, surgical treatment. J Drugs Dermatol. 2021;20(3):346-348. doi:10.36849/JDD.5660.


Assuntos
Sarda Melanótica de Hutchinson/tratamento farmacológico , Imiquimode/administração & dosagem , Ceratolíticos/administração & dosagem , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Cutâneas/tratamento farmacológico , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Sarda Melanótica de Hutchinson/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Ácidos Nicotínicos/administração & dosagem , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo
7.
Am J Dermatopathol ; 42(5): 368-371, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31584448

RESUMO

Cutaneous tuberculosis (CTB) is a challenging diagnosis that often requires tissue biopsy and the use of immunohistochemical (IHC) staining, among other special stains. The mycobacterium tuberculosis IHC stain is believed to be specific for mycobacteria and closely related organisms, without documented reactivity to normal human tissue. In this study, we document 4 cases of previously unreported cross-reactivity between the mycobacterium tuberculosis IHC polyclonal antibody and normal eosinophil granules in patients without other evidence of CTB infection. Such cross-reactivity represents a potential pitfall for the use of IHC in the diagnosis of CTB.


Assuntos
Anticorpos Antibacterianos/imunologia , Artefatos , Eosinófilos/imunologia , Imuno-Histoquímica , Tuberculose Cutânea/diagnóstico , Idoso , Reações Cruzadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Coloração e Rotulagem/métodos , Tuberculose Cutânea/imunologia
8.
Pediatr Dermatol ; 37(5): 844-848, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32643789

RESUMO

BACKGROUND/OBJECTIVES: The representation of women among practicing dermatologists has increased over the last several decades. Here, we analyze the evolving representation of women in the Society for Pediatric Dermatology (SPD) and the Pediatric Dermatology Research Alliance (PeDRA), with particular focus on the role of women as society leaders, researchers, and annual meeting speakers. METHODS: A retrospective review of SPD and PeDRA professional society leaders (SPD presidents, PeDRA co-chairs, PeDRA executive committee members), grant recipients (pilot grant recipients, team/collaborative grant recipients, William Weston Research Grant recipients), and annual meeting speakers (named lecturers at the SPD Annual Meeting, plenary lecturers at the PeDRA Annual Conference) was performed. Authors of research articles in Pediatric Dermatology were reviewed at three-year intervals from 1983 through 2019. The percentage of women among all leadership, grant, authorship, and lectureship categories was analyzed over time. RESULTS: Women have represented 70% of SPD presidents since 2011 and 75% of PeDRA co-chairs since 2013. The percentage of women among first and senior authors of research articles in Pediatric Dermatology increased significantly from 1983 to 2019 (Cochran Armitage test for trend, P < .01), and women earned the majority of SPD/PeDRA pilot project grants (2008-2018), collaborative team grants (2016-2018), and William Weston Research Grants (1995-2015). At SPD Annual meetings from 2010 to 2019, women comprised 44% of named lecturers but accounted for approximately 78% of the pediatric dermatology workforce (P < .01). CONCLUSION: Despite the widespread influence of women in pediatric dermatology leadership and research, gender discrepancies remain among named lecturer positions at national pediatric dermatology meetings.


Assuntos
Dermatologia , Criança , Feminino , Humanos , Liderança , Projetos Piloto , Estudos Retrospectivos , Sociedades Médicas
9.
Thorax ; 73(3): 213-221, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28780504

RESUMO

BACKGROUND: Early physical rehabilitation in the intensive care unit (ICU) has been shown to improve short-term clinical outcomes but long-term benefit has not been proven and the optimum intensity of rehabilitation is not known. METHODS: We conducted a randomised, parallel-group, allocation-concealed, assessor-blinded, controlled trial in patients who had received at least 48 hours of invasive or non-invasive ventilation. Participants were randomised in a 1:1 ratio, stratified by admitting ICU, admission type and level of independence. The intervention group had a target of 90 min physical rehabilitation per day, the control group a target of 30 min per day (both Monday to Friday). The primary outcome was the Physical Component Summary (PCS) measure of SF-36 at 6 months. RESULTS: We recruited 308 participants over 34 months: 150 assigned to the intervention and 158 to the control group. The intervention group received a median (IQR) of 161 (67-273) min of physical rehabilitation on ICU compared with 86 (31-139) min in the control group. At 6 months, 62 participants in the intervention group and 54 participants in the control group contributed primary outcome data. In the intervention group, 43 had died, 11 had withdrawn and 34 were lost to follow-up, while in the control group, 56 had died, 5 had withdrawn and 43 were lost to follow-up. There was no difference in the primary outcome at 6 months, mean (SD) PCS 37 (12.2) in the intervention group and 37 (11.3) in the control group. CONCLUSIONS: In this study, ICU-based physical rehabilitation did not appear to improve physical outcomes at 6 months compared with standard physical rehabilitation. TRIAL REGISTRATION NUMBER: ISRCTN 20436833.


Assuntos
Cuidados Críticos/métodos , Estado Terminal/reabilitação , Terapia por Exercício/métodos , Atividades Cotidianas , Adulto , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Qualidade de Vida , Respiração Artificial/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento , Reino Unido
10.
Development ; 142(19): 3394-402, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26443637

RESUMO

The unique cell cycle dynamics of meiosis are controlled by layers of regulation imposed on core mitotic cell cycle machinery components by the program of germ cell development. Although the mechanisms that regulate Cdk1/Cyclin B activity in meiosis in oocytes have been well studied, little is known about the trans-acting factors responsible for developmental control of these factors in male gametogenesis. During meiotic prophase in Drosophila males, transcript for the core cell cycle protein Cyclin B1 (CycB) is expressed in spermatocytes, but the protein does not accumulate in spermatocytes until just before the meiotic divisions. Here, we show that two interacting proteins, Rbp4 and Fest, expressed at the onset of spermatocyte differentiation under control of the developmental program of male gametogenesis, function to direct cell type- and stage-specific repression of translation of the core G2/M cell cycle component cycB during the specialized cell cycle of male meiosis. Binding of Fest to Rbp4 requires a 31-amino acid region within Rbp4. Rbp4 and Fest are required for translational repression of cycB in immature spermatocytes, with Rbp4 binding sequences in a cell type-specific shortened form of the cycB 3' UTR. Finally, we show that Fest is required for proper execution of meiosis I.


Assuntos
Ciclina B/metabolismo , Drosophila/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Meiose/fisiologia , Espermatogênese/fisiologia , Animais , Animais Geneticamente Modificados , Western Blotting , Sistemas CRISPR-Cas , Clonagem Molecular , Primers do DNA/genética , Drosophila/genética , Proteínas de Drosophila/metabolismo , Imunoprecipitação , Masculino , Microscopia de Fluorescência , RNA Polimerase II/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Bioconjug Chem ; 26(5): 899-905, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25830565

RESUMO

Nanodiscs are monodisperse, self-assembled discoidal particles that consist of a lipid bilayer encircled by membrane scaffold proteins (MSP). Nanodiscs have been used to solubilize membrane proteins for structural and functional studies and deliver therapeutic phospholipids. Herein, we report on tetramethylrhodamine (TMR) tagged nanodiscs that solubilize lipophilic MR contrast agents for generation of multimodal nanoparticles for cellular imaging. We incorporate both multimeric and monomeric Gd(III)-based contrast agents into nanodiscs and show that particles containing the monomeric agent (ND2) label cells with high efficiency and generate significant image contrast at 7 T compared to nanodiscs containing the multimeric agent (ND1) and Prohance, a clinically approved contrast agent.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Nanoestruturas/química , Imagem Óptica/métodos , Meios de Contraste/química , Gadolínio/química , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Modelos Moleculares , Conformação Molecular , Rodaminas/química , Solubilidade
19.
Biomacromolecules ; 15(8): 3190-6, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25000340

RESUMO

Inorganic polyphosphates, linear polymers of orthophosphate, occur naturally throughout biology and have many industrial applications. Their biodegradable nature makes them attractive for a multitude of uses, and it would be important to understand how polyphosphates are turned over enzymatically. Studies of inorganic polyphosphatases are, however, hampered by the lack of high-throughput methods for detecting and quantifying rates of polyphosphate degradation. We now report chromogenic and fluorogenic polyphosphate substrates that permit spectrophotometric monitoring of polyphosphate hydrolysis and allow for high-throughput analyses of both endopolyphosphatase and exopolyphosphatase activities, depending on assay configuration. These substrates contain 4-nitrophenol or 4-methylumbelliferone moieties that are covalently attached to the terminal phosphates of polyphosphate via phosphoester linkages formed during reactions mediated by EDAC (1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide). This report identifies Nudt2 as an inorganic polyphosphatase and also adds to the known coupling chemistry for polyphosphates, permitting facile covalent linkage of alcohols with the terminal phosphates of inorganic polyphosphate.


Assuntos
Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Polifosfatos/química , Hidrolases Anidrido Ácido/metabolismo , Fosfatase Alcalina/metabolismo , Digestão , Hidrólise , Nitrofenóis/química
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