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1.
Rev Neurol (Paris) ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38599976

RESUMO

Anti-CD20 monoclonal antibodies are highly-effective B-cell-depleting therapies in multiple sclerosis (MS). These treatments have expanded the arsenal of highly effective disease-modifying therapies, and have changed the landscape in understanding the pathophysiology of MS and the natural course of the disease. Nevertheless, these treatments come at the cost of immunosuppression and risk of serious infections, diminished vaccination response and treatment-related secondary hypogammaglobulinemia. However, the COVID pandemic has given way to a possibility of readapting these therapies, with most notably extended dosing intervals. While these new strategies show efficacy in maintaining inflammatory MS disease control, and although it is tempting to speculate that tailoring CD20 therapies will reduce the negative outcomes of long-term immunosuppression, it is unknown whether they provide meaningful benefit in reducing the risk of treatment-related secondary hypogammaglobulinemia and serious infections. This review highlights the available anti-CD20 therapies that are available for treating MS patients, and sheds light on encouraging data, which propose that tailoring anti-CD20 monoclonal antibodies is the next step in rethinking the current treatment strategy.

2.
Phys Rev Lett ; 130(20): 202501, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37267578

RESUMO

We demonstrate a new technique for obtaining fission data for nuclei away from ß stability. These types of data are pertinent to the astrophysical r process, crucial to a complete understanding of the origin of the heavy elements, and for developing a predictive model of fission. These data are also important considerations for terrestrial applications related to power generation and safeguarding. Experimentally, such data are scarce due to the difficulties in producing the actinide targets of interest. The solenoidal-spectrometer technique, commonly used to study nucleon-transfer reactions in inverse kinematics, has been applied to the case of transfer-induced fission as a means to deduce the fission-barrier height, among other variables. The fission-barrier height of ^{239}U has been determined via the ^{238}U(d,pf) reaction in inverse kinematics, the results of which are consistent with existing neutron-induced fission data indicating the validity of the technique.

3.
J Am Acad Dermatol ; 88(5): 1060-1065, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36720365

RESUMO

BACKGROUND: Mohs micrographic surgery (MMS) for melanoma practices vary among dermatologic surgeons. The implementation of immunohistochemical staining in MMS for melanoma mitigates challenges associated with slide interpretation; however, the reliability of melanoma antigen recognized by T cells 1 (MART-1), the preferred immunostain for melanoma, has yet to be compared with permanent section pathology. OBJECTIVE: To assess concordance rates of MART-1 frozen sections and permanent section pathologic interpretation of melanoma treated with MMS. METHODS: A dual-center retrospective analysis was conducted to collect concordance and demographic data. Chi-square tests were performed for group comparisons of categorical variables. RESULTS: Of the 379 permanent sections sent, 367 were concordant with frozen section pathology for an overall concordance rate of 96.8%. Cases were stratified into indeterminately concordant and indisputably concordant. Twenty-two (6%) of cases were indeterminately concordant, whereas 345 (94.0%) of cases were indisputably concordant. LIMITATIONS: The concordance rate is derived from a comparison of adjacent tissue margins, an inevitable consequence of utilizing 2 techniques. CONCLUSION: To the author's knowledge, this study represents the largest investigation examining concordance rates of MART-1 frozen sections in Mohs for melanoma. High concordance disputes the ongoing need for additional permanent margins when using MART-1 in routine cases.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Cirurgia de Mohs/métodos , Estudos Retrospectivos , Imuno-Histoquímica , Reprodutibilidade dos Testes , Melanoma/patologia , Neoplasias Cutâneas/patologia , Secções Congeladas , Melanoma Maligno Cutâneo
4.
Dermatol Surg ; 49(12): 1139-1142, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37712760

RESUMO

BACKGROUND: Tranexamic acid (TXA) is increasingly being used to prevent hemorrhagic complications after dermatologic surgery. Interpolated flap repairs following Mohs micrographic surgery are at risk for increased bleeding events and unplanned health care utilization, particularly among patients on antithrombotic medication. OBJECTIVE: To assess bleeding events after interpolated flap repair in patients receiving TXA compared with those who did not. MATERIALS AND METHODS: A retrospective review identified interpolated flap repairs in a 5-year period. Hemorrhagic complications were analyzed, defined as major bleeding events, which included all unplanned medical visits, and minor bleeding events, which included any unplanned patient phone calls or messages through electronic medical record. RESULTS: One hundred fifteen patients had interpolated flap repair during the 5-year period, of which 21 (18.3%) received TXA postprocedure. Twenty-seven bleeding events were identified in the non-TXA group compared with 1 event in the TXA-treated group. Patients who received TXA were less likely to have had a bleeding event (28.7% vs 4.8%, p < .01). CONCLUSION: Patients undergoing interpolation flap repair were less likely to experience a bleeding event after subcutaneous injection of TXA.


Assuntos
Antifibrinolíticos , Ácido Tranexâmico , Humanos , Estudos Retrospectivos , Estudos de Coortes , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle
5.
Phys Rev Lett ; 129(15): 152501, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269970

RESUMO

Absolute cross sections for the addition of s- and d-wave neutrons to ^{14}C and ^{14}N have been determined simultaneously via the (d,p) reaction at 10 MeV/u. The difference between the neutron and proton separation energies, ΔS, is around -20 MeV for the ^{14}C+n system and +8 MeV for ^{14}N+n. The population of the 1s_{1/2} and 0d_{5/2} orbitals for both systems is reduced by a factor of approximately 0.5 compared with the independent single-particle model, or about 0.6 when compared with the shell model. This finding strongly contrasts with results deduced from intermediate-energy knockout reactions between similar nuclei on targets of ^{9}Be and ^{12}C. The simultaneous technique used removes many systematic uncertainties.

6.
Atmos Environ (1994) ; 244: 117834, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32895604

RESUMO

Global aviation operations contribute to anthropogenic climate change via a complex set of processes that lead to a net surface warming. Of importance are aviation emissions of carbon dioxide (CO2), nitrogen oxides (NOx), water vapor, soot and sulfate aerosols, and increased cloudiness due to contrail formation. Aviation grew strongly over the past decades (1960-2018) in terms of activity, with revenue passenger kilometers increasing from 109 to 8269 billion km yr-1, and in terms of climate change impacts, with CO2 emissions increasing by a factor of 6.8 to 1034 Tg CO2 yr-1. Over the period 2013-2018, the growth rates in both terms show a marked increase. Here, we present a new comprehensive and quantitative approach for evaluating aviation climate forcing terms. Both radiative forcing (RF) and effective radiative forcing (ERF) terms and their sums are calculated for the years 2000-2018. Contrail cirrus, consisting of linear contrails and the cirrus cloudiness arising from them, yields the largest positive net (warming) ERF term followed by CO2 and NOx emissions. The formation and emission of sulfate aerosol yields a negative (cooling) term. The mean contrail cirrus ERF/RF ratio of 0.42 indicates that contrail cirrus is less effective in surface warming than other terms. For 2018 the net aviation ERF is +100.9 milliwatts (mW) m-2 (5-95% likelihood range of (55, 145)) with major contributions from contrail cirrus (57.4 mW m-2), CO2 (34.3 mW m-2), and NOx (17.5 mW m-2). Non-CO2 terms sum to yield a net positive (warming) ERF that accounts for more than half (66%) of the aviation net ERF in 2018. Using normalization to aviation fuel use, the contribution of global aviation in 2011 was calculated to be 3.5 (4.0, 3.4) % of the net anthropogenic ERF of 2290 (1130, 3330) mW m-2. Uncertainty distributions (5%, 95%) show that non-CO2 forcing terms contribute about 8 times more than CO2 to the uncertainty in the aviation net ERF in 2018. The best estimates of the ERFs from aviation aerosol-cloud interactions for soot and sulfate remain undetermined. CO2-warming-equivalent emissions based on global warming potentials (GWP* method) indicate that aviation emissions are currently warming the climate at approximately three times the rate of that associated with aviation CO2 emissions alone. CO2 and NOx aviation emissions and cloud effects remain a continued focus of anthropogenic climate change research and policy discussions.

7.
Pediatr Dermatol ; 38(2): 477-480, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33534174

RESUMO

Whitening of the nail, or leukonychia, can have a wide range of etiologies including genetic disorders, trauma, poisoning, autoimmune disorders, and infections. Here we detail a case of idiopathic acquired leukonychia totalis in a 17-year-old boy. This condition has been reported 13 times in the literature previously, with only young boys being affected. Proper diagnosis may help minimize unnecessary investigations and prevent additional psychological stress over whether an underlying disease is present.


Assuntos
Hipopigmentação , Doenças da Unha , Adolescente , Humanos , Masculino , Doenças da Unha/congênito , Doenças da Unha/diagnóstico , Doenças da Unha/etiologia , Unhas
8.
Ann Oncol ; 31(5): 590-598, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32245699

RESUMO

BACKGROUND: Little is known about mechanisms of resistance to poly(adenosine diphosphate-ribose) polymerase inhibitors (PARPi) and platinum chemotherapy in patients with metastatic breast cancer and BRCA1/2 mutations. Further investigation of resistance in clinical cohorts may point to strategies to prevent or overcome treatment failure. PATIENTS AND METHODS: We obtained tumor biopsies from metastatic breast cancer patients with BRCA1/2 deficiency before and after acquired resistance to PARPi or platinum chemotherapy. Whole exome sequencing was carried out on each tumor, germline DNA, and circulating tumor DNA. Tumors underwent RNA sequencing, and immunohistochemical staining for RAD51 foci on tumor sections was carried out for functional assessment of intact homologous recombination (HR). RESULTS: Pre- and post-resistance tumor samples were sequenced from eight patients (four with BRCA1 and four with BRCA2 mutation; four treated with PARPi and four with platinum). Following disease progression on DNA-damaging therapy, four patients (50%) acquired at least one somatic reversion alteration likely to result in functional BRCA1/2 protein detected by tumor or circulating tumor DNA sequencing. Two patients with germline BRCA1 deficiency acquired genomic alterations anticipated to restore HR through increased DNA end resection: loss of TP53BP1 in one patient and amplification of MRE11A in another. RAD51 foci were acquired post-resistance in all patients with genomic reversion, consistent with reconstitution of HR. All patients whose tumors demonstrated RAD51 foci post-resistance were intrinsically resistant to subsequent lines of DNA-damaging therapy. CONCLUSIONS: Genomic reversion in BRCA1/2 was the most commonly observed mechanism of resistance, occurring in four of eight patients. Novel sequence alterations leading to increased DNA end resection were seen in two patients, and may be targetable for therapeutic benefit. The presence of RAD51 foci by immunohistochemistry was consistent with BRCA1/2 protein functional status from genomic data and predicted response to later DNA-damaging therapy, supporting RAD51 focus formation as a clinically useful biomarker.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Platina/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
9.
Phys Rev Lett ; 124(6): 062502, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109128

RESUMO

The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical r process in producing nuclei heavier than A∼190. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in ^{207}Hg have been probed using the neutron-adding (d,p) reaction in inverse kinematics. The radioactive beam of ^{206}Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of ^{207}Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the r process.

12.
Clin Radiol ; 74(11): 894.e19-894.e25, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31296337

RESUMO

AIM: To assess prostate magnetic resonance imaging (MRI) image quality and compliance with technical standards between centres in the South West region of the UK. MATERIALS AND METHODS: Fifteen imaging sites in the region submitted seven consecutive anonymised MRI studies. These were assessed by two experienced radiologists in consensus. Overall, subjective image quality for T2-weighted imaging (T2W), diffusion weighted imaging (DWI), and dynamic contrast enhancement (DCE) was scored on a five-point Likert scale. Five additional quality parameters were also assessed visually, including image noise, motion, artefact, and distortion. The degree of compliance by each site with 21 published technical standards was also assessed. RESULTS: Ninety-four MRI examinations were reviewed from across all sites (mean 6.3 scans per site, range 5-7). Mean compliance with technical standards was 63% (range 38-86%). Forty-seven percent of sites did not perform DCE. One site used a 3 T scanner. The percentage of patients with overall quality scores of ≥3 (diagnostically acceptable) were 68% for T2W, 81% for DWI, and 60% for both T2W and DWI. Ninety-three percent of the 45 patients who underwent DCE had diagnostically acceptable studies. By scanner age, the percentage of patients with diagnostically acceptable T2W scores was 53% for scanners ≥7 years and 80% when <7 years (p=0.006). Comparing individual sites, the mean overall quality scores were 2.9 (range 2.2-4.2) for T2W, 3.2 (1.8-4.7) for DWI, and 3.4 (2.5-4.7) for DCE. CONCLUSION: There is wide variation in compliance with recognised technical standards and image quality across sites. If MRI is to replace biopsy in selected low-risk patients, improvements in image quality may be required.


Assuntos
Imageamento por Ressonância Magnética/normas , Neoplasias da Próstata/patologia , Desenho de Equipamento , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Prática Profissional/normas , Prática Profissional/estatística & dados numéricos , Qualidade da Assistência à Saúde , Padrões de Referência , Reino Unido
13.
J Neurooncol ; 136(3): 605-611, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29188529

RESUMO

The management of spinal cord ependymomas in Neurofibromatosis Type 2 (NF2) has traditionally been conservative, in contrast to the management of sporadic cases; the assumption being that, in the context of NF2, they did not cause morbidity. With modern management and improved outcome of other NF2 tumours, this assumption, and therefore the lack of role for surgery, has been questioned. To compare the outcome of conservative treatment of spinal ependymomas in NF2 with surgical intervention in selected patients. Retrospective review at two NF2 centers, Manchester, UK and Paris/Lille, France. In Manchester patients were managed conservatively. In France surgery was a treatment option. Inclusion in the study was based on tumor length of greater than 1.5 cm. The primary parameter assessed was acquired neurological deficit measured by the Modified McCormick Outcome Score. 24 patients from Manchester and 46 patients from France were analyzed. From Manchester, 27% of these patients deteriorated during the course of follow-up. This effectively represents the natural history of ependymomas in NF2. Of the surgical cases, 23% deteriorated postoperatively, but only 2/18 (11%) of those operated on in the NF2 specialist centers. Comparison of the two specialist centers Manchester/France showed a significantly improved outcome (P = 0.012, χ2 test) in the actively surgical center. Spinal ependymomas produce morbidity. Surgery can prevent or improve this in selected cases but can itself can produce morbidity. Surgery should be considered in growing/symptomatic ependymomas, particularly in the absence of overwhelming tumor load where bevacizumab is the preferred option.


Assuntos
Tratamento Conservador , Ependimoma/terapia , Neurofibromatose 2/terapia , Procedimentos Neurocirúrgicos , Neoplasias da Medula Espinal/terapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Progressão da Doença , Ependimoma/complicações , Ependimoma/patologia , Seguimentos , Humanos , Pessoa de Meia-Idade , Neurofibromatose 2/complicações , Neurofibromatose 2/patologia , Complicações Pós-Operatórias , Estudos Retrospectivos , Neoplasias da Medula Espinal/complicações , Neoplasias da Medula Espinal/patologia , Resultado do Tratamento , Carga Tumoral , Adulto Jovem
14.
Br J Cancer ; 116(10): 1294-1301, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28359078

RESUMO

BACKGROUND: Investigating tumour evolution and acquired chemotherapy resistance requires analysis of sequential tumour material. We describe the feasibility of obtaining research biopsies in women with relapsed ovarian high-grade serous carcinoma (HGSC). METHODS: Women with relapsed ovarian HGSC underwent either image-guided biopsy or intra-operative biopsy during secondary debulking, and samples were fixed in methanol-based fixative. Tagged-amplicon sequencing was performed on biopsy DNA. RESULTS: We screened 519 patients in order to enrol 220. Two hundred and two patients underwent successful biopsy, 118 of which were image-guided. There were 22 study-related adverse events (AE) in the image-guided biopsies, all grades 1 and 2; pain was the commonest AE. There were pre-specified significant AE in 3/118 biopsies (2.5%). 87% biopsies were fit-for-purpose for genomic analyses. Median DNA yield was 2.87 µg, and was higher in biopsies utilising 14 G or 16 G needles compared to 18 G. TP53 mutations were identified in 94.4% patients. CONCLUSIONS: Obtaining tumour biopsies for research in relapsed HGSC is safe and feasible. Adverse events are rare. The large majority of biopsies yield sufficient DNA for genomic analyses-we recommend use of larger gauge needles and methanol fixation for such biopsies, as DNA yields are higher but with no increase in AEs.


Assuntos
Carcinoma/genética , Carcinoma/secundário , DNA de Neoplasias/análise , Biópsia Guiada por Imagem , Neoplasias Hepáticas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Classe I de Fosfatidilinositol 3-Quinases , Análise Mutacional de DNA , DNA de Neoplasias/isolamento & purificação , Receptores ErbB/genética , Estudos de Viabilidade , Feminino , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Biópsia Guiada por Imagem/instrumentação , Fígado/patologia , Neoplasias Hepáticas/secundário , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Omento/patologia , PTEN Fosfo-Hidrolase/genética , Dor/etiologia , Neoplasias Peritoneais/secundário , Peritônio/patologia , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética
16.
Clin Radiol ; 72(11): 981-990, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28842113

RESUMO

Diffusion weighted imaging (DWI) has become an essential part of the gynaecological magnetic resonance imaging (MRI) protocol. DWI is used as an adjunct to conventional MRI sequences and has been shown to improve reporting accuracy in the imaging of gynaecological malignancy. In this review, we discuss the role of DWI in the diagnosis, staging, and assessment of treatment response of endometrial, cervical, and ovarian cancer. We also review the role of DWI in the assessment of the sonographically indeterminate ovarian lesion. Further, we highlight potential pitfalls that can beset the accurate interpretation of DWI in patients with gynaecological malignancy.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Feminino , Genitália Feminina/diagnóstico por imagem , Humanos
17.
Clin Otolaryngol ; 42(6): 1329-1337, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28371358

RESUMO

BACKGROUND: It is common for patients with neurofibromatosis type 2 to develop bilateral profound hearing loss hearing loss, and this is one of the main determinants of quality of life in this patient group. OBJECTIVES: The aim of this systematic review was to review the current literature regarding hearing outcomes of treatments for vestibular schwannomas in neurofibromatosis type 2 including conservative and medical management, radiotherapy, hearing preservation surgery and auditory implantation in order to determine the most effective way of preserving or rehabilitating hearing. SEARCH STRATEGY: A MESH search in PubMed using search terms (('Neurofibromatosis 2' [Mesh]) AND 'Neuroma, Acoustic'[Mesh]) AND 'Hearing Loss' [Mesh] was performed. A search using keywords was also performed. Studies with adequate hearing outcome data were included. With the exception of the cochlear implant studies (cohort size was very small), case studies were excluded. EVALUATION METHOD: The GRADE system was used to assess quality of publication. Formal statistical analysis of data was not performed because of very heterogenous data reporting. RESULTS: Conservative management offers the best chance of hearing preservation in stable tumours. The use of bevacizumab probably improves the likelihood of hearing preservation in growing tumours in the short term and is probably more effective than hearing preservation surgery and radiotherapy in preserving hearing. Of the hearing preservation interventions, hearing preservation surgery probably offers better hearing preservation rates than radiotherapy for small tumours but recurrence rates for hearing preservation surgery were high. For patients with profound hearing loss, cochlear implantation provides significantly better auditory outcomes than auditory brainstem implantation. Patients with untreated stable tumours are likely to achieve the best outcomes from cochlear implantation. Those who have had their tumours treated with surgery or radiotherapy do not gain as much benefit from cochlear implantation than those with untreated tumours. CONCLUSIONS: This review summarises the current literature related to hearing preservation/rehabilitation in patients with NF2. Whilst it provides indicative data, the quality of the data was low and should be interpreted with care. It is also important to consider that the management of vestibular schwannomas in NF2 is complex and decision-making is determined by many factors, not just the need to preserve hearing.


Assuntos
Perda Auditiva/etiologia , Perda Auditiva/terapia , Neurofibromatose 2/complicações , Perda Auditiva/diagnóstico , Humanos , Neurofibromatose 2/diagnóstico , Neurofibromatose 2/terapia
18.
Nature ; 467(7313): 285-90, 2010 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-20644535

RESUMO

Somatic cell nuclear transfer and transcription-factor-based reprogramming revert adult cells to an embryonic state, and yield pluripotent stem cells that can generate all tissues. Through different mechanisms and kinetics, these two reprogramming methods reset genomic methylation, an epigenetic modification of DNA that influences gene expression, leading us to hypothesize that the resulting pluripotent stem cells might have different properties. Here we observe that low-passage induced pluripotent stem cells (iPSCs) derived by factor-based reprogramming of adult murine tissues harbour residual DNA methylation signatures characteristic of their somatic tissue of origin, which favours their differentiation along lineages related to the donor cell, while restricting alternative cell fates. Such an 'epigenetic memory' of the donor tissue could be reset by differentiation and serial reprogramming, or by treatment of iPSCs with chromatin-modifying drugs. In contrast, the differentiation and methylation of nuclear-transfer-derived pluripotent stem cells were more similar to classical embryonic stem cells than were iPSCs. Our data indicate that nuclear transfer is more effective at establishing the ground state of pluripotency than factor-based reprogramming, which can leave an epigenetic memory of the tissue of origin that may influence efforts at directed differentiation for applications in disease modelling or treatment.


Assuntos
Epigênese Genética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Reprogramação Celular/genética , Metilação de DNA/genética , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Genoma/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Técnicas de Transferência Nuclear , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
J Med Genet ; 52(6): 422-4, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25725045

RESUMO

BACKGROUND: Neurofibromatosis type 2 (NF2) is an autosomal dominant condition with high spontaneous mutation rate which predisposes to the development of multiple nerve sheath tumours (schwannomas), meningiomas and ependymoma. The cardinal feature and main diagnostic criterion for the diagnosis of NF2 remains the development of bilateral vestibular schwannoma (BVS). With increasing use of MRI screening the possibility of a 'chance' diagnosis of BVS has been mooted with a potential frequency of one in two million people in their lifetime. Until now, however, no evidence for such an event has been published. We aimed to demonstrate that chance occurrence can occur and to estimate its frequency among those with just BVS late in life. METHODS: Two vestibular schwannomas from the same patient were DNA sequenced and underwent loss of heterozygosity analysis. RESULTS: We show that a man who developed BVS, at ages 52 and 67 years developed these tumours sporadically by demonstrating that there were no molecular events in common between the two tumours. Furthermore from a database of over 1200 patients with NF2, we have estimated that ~25% of cases of BVS over 50 years and 50% over 70 years of age where no other features of NF2 are present represent a chance occurrence rather than due to an underlying mosaic or constitutional NF2 mutation. CONCLUSIONS: Patients presenting with BVS later in life should be appraised of the potential likelihood they may not have NF2 and the resultant further reduction in risks of transmission to offspring.


Assuntos
Neuroma Acústico/diagnóstico , Neuroma Acústico/genética , Idade de Início , Idoso , Diagnóstico Diferencial , Genes da Neurofibromatose 2 , Humanos , Perda de Heterozigosidade , Pessoa de Meia-Idade , Mutação , Neurofibromatose 2/diagnóstico , Neurofibromatose 2/genética
20.
J Zool (1987) ; 299(2): 106-115, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27453637

RESUMO

Social monogamy is a mating strategy rarely employed by mammalian species. Laboratory studies in socially monogamous prairie voles (Microtus ochrogaster) demonstrate that oxytocin and vasopressin act within the mesolimbic dopamine pathway to facilitate pair-bond formation. Species differences in oxytocin receptor (OTR) and vasopressin 1a receptor (V1aR) distribution in this pathway are associated with species differences in mating strategy. Here we characterize the neuroanatomical distribution of OTR and V1aR binding sites in naturally occurring populations of Taiwan voles (M. kikuchii), which purportedly display social monogamy. Live trapping was conducted at two sites in 2009-2010 and receptor autoradiography for OTR and V1aR was performed on brains from 24 animals. OTR binding in two brain regions where OTR signaling regulates pair-bonding were directly compared with that of prairie voles. Our results show that like prairie voles, Taiwan voles exhibit OTR in the prefrontal cortex, insular cortex, claustrum, nucleus accumbens, caudate-putamen, dorsal lateral septal nucleus, central amygdala, and ventromedial hypothalamus. Unlike prairie voles, Taiwan voles exhibit OTR binding in the CA3 pathway of the hippocampus, as well as the indusium griseum, which has only previously been documented in tuco-tucos (Ctenomys haigi, C. sociabilis), Syrian hamsters (Mesocricetus auratus) and naked mole-rats (Heterocephalus glaber). V1aR binding was present in the ventral pallidum, lateral septum, nucleus basalis, bed nucleus of the stria terminalis, hippocampus, medial amygdala, and anterior, ventromedial and dorsomedial hypothalamus. Marked individual differences in V1aR binding were noted in the cingulate cortex and several thalamic nuclei, remarkably similar to prairie voles. While pharmacological studies are needed to determine whether oxytocin and vasopressin are involved in pair-bond formation in this species, our results lay a foundation for future investigations into the role of these neuropeptides in Taiwan vole social behavior.

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