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1.
Plant Cell ; 32(1): 100-122, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666295

RESUMO

Gene functional studies often rely on the expression of a gene of interest as transcriptional and translational fusions with specialized tags. Ideally, this is done in the native chromosomal contexts to avoid potential misexpression artifacts. Although recent improvements in genome editing have made it possible to directly modify the target genes in their native chromosomal locations, classical transgenesis is still the preferred experimental approach chosen in most gene tagging studies because of its time efficiency and accessibility. We have developed a recombineering-based tagging system that brings together the convenience of the classical transgenic approaches and the high degree of confidence in the results obtained by direct chromosomal tagging using genome-editing strategies. These simple, scalable, customizable recombineering toolsets and protocols allow a variety of genetic modifications to be generated. In addition, we developed a highly efficient recombinase-mediated cassette exchange system to facilitate the transfer of the desired sequences from a bacterial artificial chromosome clone to a transformation-compatible binary vector, expanding the use of the recombineering approaches beyond Arabidopsis (Arabidopsis thaliana). We demonstrated the utility of this system by generating more than 250 whole-gene translational fusions and 123 Arabidopsis transgenic lines corresponding to 62 auxin-related genes and characterizing the translational reporter expression patterns for 14 auxin biosynthesis genes.


Assuntos
Plantas Geneticamente Modificadas/genética , Recombinação Genética , Arabidopsis/genética , Cromossomos Artificiais Bacterianos , Edição de Genes/métodos , Genes Reporter , Engenharia Genética/métodos , Plantas/genética
2.
Phys Rev Lett ; 130(17): 176901, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172240

RESUMO

Magnetic 2D materials hold promise to change the miniaturization paradigm of unidirectional photonic components. However, the integration of these materials in devices hinges on the accurate determination of the optical properties down to the monolayer limit, which is still missing. By using hyperspectral wide-field imaging at room temperature, we reveal a nonmonotonic thickness dependence of the complex optical dielectric function in the archetypal magnetic 2D material CrI_{3} extending across different length scales: onsetting at the mesoscale, peaking at the nanoscale, and decreasing again down to the single layer. These results portray a modification of the electronic properties of the material and align with the layer-dependent magnetism in CrI_{3}, shedding light on the long-standing structural conundrum in this material. The unique modulation of the complex dielectric function from the monolayer up to more than 100 layers will be instrumental for understanding mesoscopic effects in layered materials and tuning light-matter interactions in magnetic 2D materials.

3.
World J Urol ; 41(8): 2209-2215, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37354260

RESUMO

PURPOSE: To evaluate the safety and efficacy of the Optilume BPH Catheter System for the treatment of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). METHODS: This open-label, single-arm study enrolled eighty subjects with LUTS secondary to BPH who were treated with the Optilume BPH Catheter System. Symptoms were recorded utilizing the International Prostate Symptom Score (IPSS) and Benign Prostatic Hyperplasia Impact Index (BPH-II). Functional improvement was measured utilizing peak urinary flow rate (Qmax) and post-void residual urine volume (PVR). Adverse events were systematically captured and reported at each follow-up visit. RESULTS: Subjects treated with the Optilume BPH Catheter System experienced a significant improvement in LUTS from baseline through 2 years of follow-up, as measured by IPSS (22.3 vs 8.2, p < 0.001) and BPH-II (6.9 vs 2.3, p < 0.001). Functional improvement was also significant, with Qmax improving from an average of 10.9 mL/s at baseline to 17.2 mL/s at the 2-year follow-up and PVR improving from 63.1 to 45.0 mL. Treatment-related adverse events were typically minor, with none occurring between 1- and 2-year post-treatment. CONCLUSIONS: The Optilume BPH Catheter System is a unique minimally invasive surgical therapy that combines mechanical and pharmaceutical aspects for the treatment of BPH. The functional and symptomatic improvements seen after treatment are significant and have been sustained through 2 years in this early feasibility study. REGISTRATION: NCT03423979, registered February 6, 2018.


Assuntos
Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/cirurgia , Resultado do Tratamento , Sintomas do Trato Urinário Inferior/cirurgia
4.
Ultraschall Med ; 43(5): e81-e89, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33316836

RESUMO

PURPOSE: To evaluate the relationship between gastrointestinal (GI) symptoms and transvaginal ultrasound (TVUS) findings suggestive of endometriosis. MATERIALS AND METHODS: A prospective design. Women referred for a diagnostic ultrasound due to suspicion of endometriosis completed a Rome III and Pelvic Floor Distress Inventory (PFDI-20) questionnaire for clinical, GI symptoms, before undergoing TVUS. Endometriosis was diagnosed in the presence of endometriomas and/or deeply infiltrative endometriotic (DIE) lesions. Association between lesion sites and GI symptoms was evaluated by univariate and multivariate analysis. RESULTS: The study included 241 women who presented with: dysmenorrhea (89.6 %), dyspareunia (76.3 %), chronic pelvic pain (77.2 %), dyschezia (66 %), hematochezia (15.4 %), subfertility (24.5 %). GI symptoms were present in 25.3-76.8 % and 5.4-55.6 % of Rome III and PFDI-20 questionnaire responses, respectively. TVUS findings were endometriomas (23.2 %), peritoneal adhesions (46.5 %), uterosacral ligament (26.7 %), retrocervical (11.2 %), rectosigmoid (11.2 %), intestinal (4.6 %), and bladder (0.8 %) involvement, and pouch of Douglas (POD) obliteration (15.4 %). There was a high prevalence of peritoneal adhesions, uterosacral ligament involvement, and rectosigmoid and intestinal nodules on TVUS in women with GI symptoms, up to Chi2 = 9.639 (p = 0.013) on univariate and Chi2 = 8.102 (p = 0.005) on multivariate analysis. CONCLUSION: We observed an almost 10-fold increase in DIE lesions in women with GI symptoms. We suggest that the presence of GI symptoms should prompt a referral for endometriosis evaluation and performance of a dedicated TVUS before invasive gastrointestinal procedures.


Assuntos
Endometriose , Doenças Peritoneais , Endometriose/diagnóstico por imagem , Endometriose/patologia , Feminino , Humanos , Doenças Peritoneais/diagnóstico por imagem , Projetos Piloto , Encaminhamento e Consulta , Sensibilidade e Especificidade , Ultrassonografia/métodos
5.
J Minim Invasive Gynecol ; 27(5): 1209-1213, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32259651

RESUMO

A pseudoaneurysm of the uterine artery or its branches is usually a result of vascular trauma during invasive procedures such as a cesarean section, vaginal delivery, myomectomy, hysterotomy, or dilatation and curettage. A uterine artery pseudoaneurysm rupture is a rare, yet life-threatening event. Deep infiltrating endometriosis usually involves a decrease in symptoms and imaging findings throughout pregnancy, with the notable exception of the phenomenon of decidualization. We present the case of a pregnant woman with a recent diagnosis of endometriosis, who conceived spontaneously and presented with disabling pain at 13 weeks' gestation. She was diagnosed with a left, huge (and rapidly growing) retrocervical endometriosis nodule encompassing a uterine artery pseudoaneurysm. Selective transarterial embolization was performed at 22 weeks' gestation owing to enlargement of the pseudoaneurysm sac, and the pseudoaneurysm was obliterated successfully. The patient was followed intensively throughout the pregnancy and the baby was delivered at term by cesarean section. After delivery, the nodule returned to the pregestational size.


Assuntos
Falso Aneurisma/diagnóstico , Falso Aneurisma/etiologia , Endometriose/complicações , Doenças Retais/complicações , Artéria Uterina/patologia , Doenças do Colo do Útero/complicações , Adulto , Falso Aneurisma/terapia , Colo do Útero/patologia , Endometriose/diagnóstico , Endometriose/terapia , Feminino , Humanos , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/etiologia , Complicações Cardiovasculares na Gravidez/terapia , Primeiro Trimestre da Gravidez , Doenças Retais/diagnóstico , Doenças Retais/terapia , Artéria Uterina/diagnóstico por imagem , Artéria Uterina/cirurgia , Embolização da Artéria Uterina , Doenças do Colo do Útero/diagnóstico , Doenças do Colo do Útero/terapia
6.
Nano Lett ; 18(3): 2033-2039, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29481087

RESUMO

Enhancing the spin-orbit interaction in graphene, via proximity effects with topological insulators, could create a novel 2D system that combines nontrivial spin textures with high electron mobility. To engineer practical spintronics applications with such graphene/topological insulator (Gr/TI) heterostructures, an understanding of the hybrid spin-dependent properties is essential. However, to date, despite the large number of experimental studies on Gr/TI heterostructures reporting a great variety of remarkable (spin) transport phenomena, little is known about the true nature of the spin texture of the interface states as well as their role on the measured properties. Here, we use ab initio simulations and tight-binding models to determine the precise spin texture of electronic states in graphene interfaced with a Bi2Se3 topological insulator. Our calculations predict the emergence of a giant spin lifetime anisotropy in the graphene layer, which should be a measurable hallmark of spin transport in Gr/TI heterostructures and suggest novel types of spin devices.

7.
J Minim Invasive Gynecol ; 23(5): 781-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27016123

RESUMO

STUDY OBJECTIVE: To assess the reproductive outcome (spontaneous and assisted conception rates) in women who underwent laparoscopic resection of bladder endometriosis. DESIGN: This was a retrospective, observational study analyzing prospectively recorded data (Canadian Task Force classification II-2). SETTING: A tertiary referral center. PATIENTS: Over a 9-year period, we identified 69 consecutive women with symptomatic pelvic endometriosis who underwent laparoscopic resection of bladder endometriosis at our center. INTERVENTIONS: Group A patients (n = 21) had full-thickness endometriotic invasion of the bladder and underwent laparoscopic partial cystectomy. Group B (n = 48) patients had partial endometriotic bladder penetration and underwent partial-thickness excision of the detrusor muscle. Most patients (over 70%) had additional, nonbladder endometriotic lesions, which were also removed during surgery. MEASUREMENTS AND MAIN RESULTS: Fertility outcomes were analyzed in patients who wished to conceive (n = 42), and improvements in symptoms were assessed for all patients. The minimum follow-up after surgery was 36 months. Of the 42 patients who wished to conceive, 35 patients (83.3%) conceived: 16 patients spontaneously and 18 patients after IVF treatment. No difference was observed in fertility outcome between group A (partial cystectomy) and group B (partial-thickness excision of the detrusor muscle). For all patients, long-term follow-up revealed that 80% of the patients (55 patients) had no urinary/endometrial symptoms after surgery. CONCLUSION: Pregnancy rates after laparoscopic surgery for bladder endometriosis by either partial cystectomy or deep excision of the detrusor muscle are favorable, both for spontaneous pregnancy and conception after IVF treatment. Additionally, urinary symptoms were improved for the majority of patients. Based on our findings, it seems warranted to offer laparoscopic surgical management to symptomatic infertile patients diagnosed with bladder endometriosis, even after IVF failure.


Assuntos
Endometriose/cirurgia , Laparoscopia , Taxa de Gravidez , Doenças da Bexiga Urinária/cirurgia , Adulto , Cistectomia , Feminino , Fertilidade , Humanos , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Bexiga Urinária/cirurgia
8.
Phys Rev Lett ; 113(24): 246603, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25541791

RESUMO

We report an intriguing transition from the quantum spin Hall phase to the spin Hall effect upon segregation of thallium adatoms adsorbed onto a graphene surface. Landauer-Büttiker and Kubo-Greenwood simulations are used to access both edge and bulk transport physics in disordered thallium-functionalized graphene systems of realistic sizes. Our findings not only quantify the detrimental effects of adatom clustering in the formation of the topological state, but also provide evidence for the emergence of spin accumulation at opposite sample edges driven by spin-dependent scattering induced by thallium islands, which eventually results in a minimum bulk conductivity ∼4e²/h, insensitive to localization effects.

9.
Aust N Z J Obstet Gynaecol ; 54(2): 162-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24576163

RESUMO

AIMS: To determine the incidence and severity of acute pelvic inflammatory disease (PID) or tubo-ovarian abscess (TOA) in hospitalised women with and without a history of endometriosis. METHODS: Retrospective analysis of hospital records retrieved for all women hospitalised with PID or TOA between January 2008 and December 2011 in a tertiary referral centre. Women were compared with regard to a history of endometriosis for demographic, clinical and fertility data. RESULTS: 26 (15%) of the 174 women hospitalised due to PID or TOA were excluded because of age older than 45 years, leaving 148 for analysis. The mean age was 35.7 ± 9.3 years and mean duration of hospitalisation was 5.9 ± 3.7 days. The women were divided into two groups: Group 1 with endometriosis (n = 21) and Group 2 without endometriosis (n = 127). Women in Group 1 as compared with Group 2 were significantly more likely to have undergone a fertility procedure prior to being admitted to the hospital with PID (9/27 (45%) vs 22/121 (17%), P < 0.001); particularly in vitro fertilisation (IVF) (7/ 27 (33%) vs 12/121 (9%), P < 0.006); Women in Group 1 more frequently experienced a severe and complicated course involving longer duration of hospitalisation (8.8 ± 4.7 vs 4.4 ± 2.3 days, P < 0.0001) and antibiotic treatment failure (10/27 (48%) vs 8/121 (6%), P < 0.0001). CONCLUSIONS: Pelvic inflammatory disease in women with endometriosis is more severe and refractory to antibiotic treatment, often requiring surgical intervention. It is likely that endometriosis is a risk factor for the development of severe PID, particularly after IVF treatment.


Assuntos
Antibacterianos/uso terapêutico , Endometriose/complicações , Doença Inflamatória Pélvica/etiologia , Adulto , Resistência Microbiana a Medicamentos , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Pessoa de Meia-Idade , Paridade , Doença Inflamatória Pélvica/classificação , Doença Inflamatória Pélvica/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
10.
PLoS One ; 19(5): e0303689, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38768169

RESUMO

An observational methodology system has been designed which allows the observation and analysis of the technical-tactical behaviour and interaction of judokas during competition. The observation instrument (JUTACTIC) is composed of 8 fixed criteria that provide information related to the competition and the competitors and 13 variable criteria that, throughout the intrasessional monitoring of each combat, allow the behaviour displayed by both judokas and their interaction to be recorded. From an observational sample consisting of matches from the Rio 2016 Olympic champions and the corresponding samples made using the LINCE PLUS software, evidence of validity, reliability, generalizability and applicability of the observation system is provided. The content validity of the observation instrument has been endorsed by a panel of experts (n = 11). Intra and inter-observer reliability has been guaranteed from the results obtained in the Fleiss Kappa and the Krippendorff Alpha. The generalizability analysis with the design structure [Category] [Participants] / [Matches] has confirmed that around seven matches are needed to accurately analyse the behaviour of the competitor under study. The practical application possibilities of the observation instrument has been shown with an example of the results obtained and the regular behaviour structures detected (T-patterns) using the THEME software.


Assuntos
Artes Marciais , Humanos , Brasil , Desempenho Atlético/fisiologia , Reprodutibilidade dos Testes , Atletas , Comportamento Competitivo , Software , Masculino , Feminino
11.
J Colloid Interface Sci ; 670: 73-85, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38759270

RESUMO

HYPOTHESIS: Multicore flower-like iron oxide nanoparticles (IONPs) are among the best candidates for magnetic hyperthermia applications against cancers. However, they are rarely investigated in physiological environments and their efficacy against cancer cells has been even less studied. The combination of magnetic hyperthermia, using multicore IONPs, with selected bioactive molecules should lead to an enhanced activity against cancer cells. EXPERIMENTS: Multicore IONPs were synthesized by a seeded-growth thermal decomposition approach. Then, the cytotoxicity, cell uptake, and efficacy of the magnetic hyperthermia approach were studied with six cancer cell lines: PANC1 (pancreatic carcinoma), Mel202 (uveal melanoma), MCF7 (breast adenocarcinoma), MB231 (triple-negative breast cancer line), A549 (lung cancer), and HCT116 (colon cancer). Finally, IONPs were modified with a chemotherapeutic drug (SN38) and tumor suppressor microRNAs (miR-34a, miR-182, let-7b, and miR-137), to study their activity against cancer cells with and without combination with magnetic hyperthermia. FINDINGS: Two types of multicore IONPs with very good heating abilities under magnetic stimulation have been prepared. Their concentration-dependent cytotoxicity and internalization have been established, showing a strong dependence on the cell line and the nanoparticle type. Magnetic hyperthermia causes significant cell death that is dramatically enhanced in combination with the bioactive molecules.


Assuntos
Hipertermia Induzida , Nanopartículas Magnéticas de Óxido de Ferro , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , MicroRNAs/metabolismo , MicroRNAs/genética , Linhagem Celular Tumoral , Tamanho da Partícula , Ensaios de Seleção de Medicamentos Antitumorais , Terapia Combinada , Propriedades de Superfície , Proliferação de Células/efeitos dos fármacos
12.
Gynecol Endocrinol ; 29(2): 169-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23134575

RESUMO

The aim of this study was to determine whether women with recurrent pregnancy loss (RPL) and concurrent premenstrual syndrome (PMS) who underwent desensitization with sex hormones had an improved obstetric outcome. This manuscript summarizes a 10 year open label prospective follow up study of 26 women with RPL, aged 25-42 with 3-8 previous miscarriages and PMS, who had hormone hypersensitivity on skin testing. Skin testing was positive to estradiol in 23 women, progesterone in 20 women and to both estrogen and progesterone in 17 women. Amelioration of the symptoms of PMS (according to the VAS) was seen in 21 of 26 patients after desensitization with small doses of sex hormones intradermally. There was long term and stable reduction of severe PMS in 21 of 26 patients after desensitization. Five women conceived after skin testing, prior to desensitization. Sixteen of 26 women (61%) had subsequent live births. Five women had two subsequent live births in the subsequent pregnancy. There were no obstetric complications. Five women had two subsequent pregnancies with live births. It seems that correction of sex hormone hypersensitivity was accompanied by relief of persistent PMS, may have a positive effect on the chances of a successful pregnancy.


Assuntos
Aborto Habitual/prevenção & controle , Dessensibilização Imunológica , Perda do Embrião/prevenção & controle , Estradiol/análogos & derivados , Síndrome Pré-Menstrual/terapia , Progesterona/administração & dosagem , Aborto Habitual/etiologia , Adulto , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Doenças Autoimunes/terapia , Estudos de Coortes , Perda do Embrião/etiologia , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Feminino , Humanos , Injeções Intradérmicas , Nascido Vivo , Estudos Longitudinais , Gravidez , Síndrome Pré-Menstrual/imunologia , Síndrome Pré-Menstrual/fisiopatologia , Progesterona/efeitos adversos , Estudos Prospectivos , Prevenção Secundária , Índice de Gravidade de Doença
13.
Arch Gynecol Obstet ; 288(6): 1323-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23778640

RESUMO

OBJECTIVE: To assess the efficacy and safety of laparoscopic treatment of bladder endometriosis, especially in cases of full thickness endometriotic nodules. DESIGN: Retrospective review of medical records. SETTING: Tertiary medical center and a referral center for endometriosis. POPULATION: Sixty-nine patients with bladder endometriosis that underwent surgery between January 2005 and December 2011. METHODS: The records of all patients with bladder endometriosis were reviewed and the pre-, intra- and postoperative information of patients who underwent surgery was collected. MAIN OUTCOME MEASURES: Efficacy, safety and long-term outcome of laparoscopic treatment of bladder endometriosis. RESULTS: The mean age of 69 patients with bladder endometriosis was 31.3 ± 4.6 years. Preoperative urinary symptoms (such as frequency, urgency, dysuria and others) were present in 28 (40.0%) patients. Laparoscopy was performed in all patients. Deep detrusor involvement was found in 45 (65.2%) patients. Of these, 21 patients underwent partial cystectomy due to a full thickness lesion. Deep nodule resection without bladder invasion was performed in 24 (34.8%) patients and bladder nodule coagulation and ablation in the remaining 24 (34.8%) patients with superficial involvement. No intraoperative complications were noted. Postoperative follow-up results were available for all patients. After a median (range) follow-up period of 60 (4-92) months, 92.7% of the patients were asymptomatic or reported improvement in symptoms. CONCLUSIONS: After a long-term follow-up surgical management of bladder endometriosis is strongly recommended. During surgery, careful inspection and full excision of bladder lesions should be performed. Laparoscopic excision is a safe and efficacies approach.


Assuntos
Endometriose/cirurgia , Laparoscopia/métodos , Doenças da Bexiga Urinária/cirurgia , Adulto , Idoso , Cistectomia/métodos , Dispareunia/etiologia , Disuria/etiologia , Endometriose/complicações , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
14.
Sci Adv ; 9(7): eade5706, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791201

RESUMO

Van der Waals coupling with different stacking configurations is emerging as a powerful method to tune the optical and electronic properties of atomically thin two-dimensional materials. Here, we investigate 3R-stacked transition-metal dichalcogenides as a possible option for high-performance atomically thin field-effect transistors (FETs). We report that the effective mobility of 3R bilayer WS2 (WSe2) is 65% (50%) higher than that of 2H WS2 (WSe2). The 3R bilayer WS2 n-type FET exhibits a high on-state current of 480 µA/µm at Vds = 1 V and an ultralow on-state resistance of 1 kilohm·µm. Our observations, together with multiscale simulations, reveal that these improvements originate from the strong interlayer coupling in the 3R stacking, which is reflected in a higher conductance compared to the 2H stacking. Our method provides a general and scalable route toward advanced channel materials in future electronic devices for ultimate scaling, especially for complementary metal oxide semiconductor applications.

15.
Mater Today Bio ; 23: 100817, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37822453

RESUMO

Immunotherapy has emerged as a promising strategy to eradicate cancer cells. Particularly, the development of cancer vaccines to induce a potent and sustained antigen-specific T cell response has become a center of attention. Herein, we describe a novel immunotherapy based on magnetic nanoparticles (MNP) covalently modified with the OVA254-267 antigen and a CpG oligonucleotide via disulfide bonds. The MNP-CpG-COVA significantly enhances dendritic cell activation and CD8+ T cell antitumoral response against B16-OVA melanoma cells in vitro. Notably, the immune response induced by the covalently modified MNP is more potent and sustained over time than that triggered by the free components, highlighting the advantage of nanoformulations in immunotherapies. What is more, the nanoparticles are stable in the blood after in vivo administration and induce potent levels of systemic tumor-specific effector CD8 + T cells. Overall, our findings highlight the potential of covalently functionalized MNP to induce robust immune responses against mouse melanoma.

17.
Phys Rev Lett ; 109(26): 266805, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368601

RESUMO

We design three-dimensional models of topological insulator thin films, showing a tunability of the odd number of Dirac cones driven by the atomic-scale geometry at the boundaries. A single Dirac cone at the Γ-point can be obtained as well as full suppression of quantum tunneling between Dirac states at geometrically differentiated surfaces. The spin texture of surface states changes from a spin-momentum-locking symmetry to a surface spin randomization upon the introduction of bulk disorder. These findings illustrate the richness of the Dirac physics emerging in thin films of topological insulators and may prove utile for engineering Dirac cones and for quantifying bulk disorder in materials with ultraclean surfaces.

18.
J Minim Invasive Gynecol ; 19(6): 742-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23084679

RESUMO

STUDY OBJECTIVE: To evaluate the clinical and surgical features of thoracic endometriosis syndrome (TES) represented by catamenial pneumothorax and pelvic endometriosis and to describe their association with infertility. DESIGN: Retrospective clinical study (Canadian Task Force classification: II-2). SETTING: Academic tertiary referral endometriosis center. PATIENTS: Seven patients who had undergone surgery because of thoracic and pelvic endometriosis between 2004 and 2010. INTERVENTIONS: Thoracic and pelvic exploration and treatment and fertility treatment. MEASUREMENTS AND MAIN RESULTS: Concurrently, thoracic and pelvic endometriosis, and subsequent fertility were determined during long-term follow-up after combined surgical and pharmacologic interventions. The most frequent thoracic finding was diaphragmatic implants. Except for 1 patient with recurrent pleurodesis at 1 month after video-assisted thoracoscopy, no patients experienced recurrence of thoracic symptoms during a median (range) follow-up of 31.4 (1-61) months. Severe pelvic endometriosis was diagnosed in 6 patients with notable urologic and gastrointestinal tract involvement. Only 1 patient with catamenial pneumothorax had no macroscopic pelvic lesions. There was a considerable delay between the onset of pelvic symptoms and diagnosis. Median postoperative follow-up was 31.5 (7-84) months. Most patients who tried to conceive had primary infertility. CONCLUSION: Thoracic endometriosis syndrome, represented by catamenial pneumothorax, was strongly associated with severe pelvic endometriosis and a high rate of infertility. Inasmuch as many patients with thoracic endometriosis syndrome are treated by thoracic surgeons using video-assisted thoracoscopy, it is desirable to involve an experienced gynecologist who can diagnose and treat concurrent pelvic endometriosis.


Assuntos
Endometriose/complicações , Doenças Urogenitais Femininas/complicações , Pneumopatias/complicações , Doenças Pleurais/complicações , Adolescente , Adulto , Diafragma , Dismenorreia/tratamento farmacológico , Dismenorreia/etiologia , Endometriose/terapia , Feminino , Doenças Urogenitais Femininas/diagnóstico , Doenças Urogenitais Femininas/terapia , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Infertilidade Feminina/complicações , Pneumopatias/terapia , Doenças Pleurais/terapia , Pleurodese , Pneumonectomia , Pneumotórax/etiologia , Pneumotórax/cirurgia , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida , Adulto Jovem
19.
J Colloid Interface Sci ; 613: 447-460, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35051720

RESUMO

Stimuli-responsive nanomaterials are very attractive for biomedical applications. They can be activated through external stimuli or by the physico-chemical conditions present in cells or tissues. Here, we describe the preparation of hybrid iron oxide-manganese oxide core-satellite shell nanostructures that change their contrast mode in magnetic resonance imaging (MRI) from T2 to T1, after being internalized by cells. This occurs by the dissolution of the MnO2 of the shell, preserving intact the iron oxide at the core. First, we study the seeded-growth synthesis of iron oxide-manganese oxide nanoparticles studying the effect of varying the core size of the magnetic seeds and the concentration of the surfactant. This allows tuning the size and shape of the final hybrid nanostructure. Then, we show that the shell can be removed by a redox reaction with glutathione, which is naturally present inside the cells at much higher concentrations than outside the cells. Finally, the dissolution of the MnO2 shell and the change in the contrast mode is confirmed in cell cultures. After this process, the iron oxide nanoparticles at the core remain intact and are still active as heating mediators when an alternating magnetic field is applied.


Assuntos
Compostos de Manganês , Nanopartículas , Compostos Férricos , Imageamento por Ressonância Magnética , Óxidos
20.
Pharmaceutics ; 14(8)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893782

RESUMO

The clinical implementation of magnetic hyperthermia has experienced little progress since the first clinical trial was completed in 2005. Some of the hurdles to overcome are the reliable production of magnetic nanoparticles with controlled properties and the control of the temperature at the target tissue in vivo. Here, forty samples of iron oxide superparamagnetic nanoparticles were prepared by similar methods and thoroughly characterized in terms of size, aggregation degree, and heating response. Selected samples were intratumorally administered in animals with subcutaneous xenografts of human pancreatic cancer. In vivo experiments showed that it is possible to control the rise in temperature by modulating the field intensity during in vivo magnetic hyperthermia protocols. The procedure does not require sophisticated materials and it can be easily implemented by researchers or practitioners working in magnetic hyperthermia therapies.

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