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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065181

RESUMO

This work presents the design and validation of a vibrating coil magnetometer for the characterization of the field dependence of the critical current density of centimeter-sized bulk superconductors as an alternative to the destructive methods typically used. The magnetometer is also shown to be capable of measuring the magnetic moment in an applied field of up to 5 T for diverse magnetic materials, such as soft and hard ferromagnets and high-temperature superconducting pellets. The vibrating coil magnetometer was first optimized using finite element simulations and calibrated using a commercial vibrating sample magnetometer. The vibrating coil magnetometer was benchmarked with hysteresis measurements of a Nd2Fe14B disk made with a commercial hysteresisgraph, showing good agreement between the different setups. The magnetic hysteresis of a YBa2Cu3O7-x superconducting pellet was measured at 77 K, showing a penetration field of 1 T and an irreversibility field of 4 T. The field dependent critical current density of the superconductor was then inferred from the magnetic hysteresis measurements and extrapolated at low fields. Finally, the resulting critical current density was used to successfully reproduce the measured magnetization curve of the pellet at 2 T with finite element simulations.

2.
Int J Impot Res ; 33(8): 793-800, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32488213

RESUMO

The aim of the present systematic review is to evaluate the impact of gender reassignment surgery on the development of urethral complication. A systematic search in accordance the Preferred Reporting Items for Systematic Review and Meta-Analyses statement for original articles published up until June 2019 was performed using the Pubmed, Scopus, Embase, and Web of Science databases. Pooled analyses were done when appropriate. The bibliographic search with the included terms (("Transsexualism"[Mesh])) AND ("Sex Reassignment Surgery"[Mesh]) produced a literature of 879 articles altogether. After removing papers of not interest or articles in which the outcomes could not be deduced, 32 studies were examined for a total of 3463 patients screened. Thirty-two studies met our inclusion criteria and were evaluated, and references were manually reviewed in order to include additional relevant studies in this review. Female-to-male (FtM) surgery and male-to-female (MtF) surgery was discussed in 23 and 10 studies, respectively. One study discussed both. Varying patterns of complications were observed in FtM and MtF surgeries, with increased complications in the former because of the larger size of the neourethra. Meatal stenosis is a particular concern in MtF surgery, with complication rates ranging from 4 to 40%, and usually require meatotomy for repair. Stricture and fistulization are frequently reported complications following FtM surgery. In studies reporting on fistulae involving the urethra, 19-54% of fistulae resolved spontaneously without further surgical intervention. High rates of complications are reported in the current literature, which should be understood by patients and practitioners alike. Shared decision making with patients regarding incidence and management of urethral complications including stricture disease and fistulae, particularly after FtM surgery, is critical for setting expectations and managing postoperative outcomes.


Assuntos
Cirurgia de Readequação Sexual , Transexualidade , Feminino , Humanos , Masculino , Cirurgia de Readequação Sexual/efeitos adversos , Transexualidade/cirurgia , Uretra/cirurgia
3.
Am J Transplant ; 17(9): 2451-2457, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28489287

RESUMO

Concerns regarding the potential for broken chains and "reneges" within kidney paired donation (KPD) and its effect on chain length have been raised previously. Although these concerns have been tested in simulation studies, real-world data have yet to be evaluated. The purpose of this study was to evaluate the actual rate and causes of broken chains within a large KPD program. All patients undergoing renal transplantation through the National Kidney Registry from 2008 through May 2016 were included for analysis. Broken chains and loops were identified. A total of 344 chains and 78 loops were completed during the study period, yielding a total of 1748 transplants. Twenty broken chains and one broken loop were identified. The mean chain length (number of transplants) within broken chains was 4.8 compared with 4.6 of completed chains (p = 0.78). The most common causes of a broken chain were donor medical issues incurred while acting as a bridge donor (n = 8), donors electing not to proceed (n = 6), and kidneys being declined by the recipient surgeon (n = 4). All recipients involved in a broken chain subsequently received a transplant. Based on the results, broken chains are infrequent, are rarely due to lack of donor motivation, and have no significant impact on chain length.


Assuntos
Seleção do Doador , Falência Renal Crônica/cirurgia , Transplante de Rim , Doadores Vivos/provisão & distribuição , Obtenção de Tecidos e Órgãos , Humanos , Prognóstico , Sistema de Registros , Listas de Espera
4.
J Minim Invasive Gynecol ; 22(6S): S152, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27678858
5.
Gene Ther ; 22(2): 138-45, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25427613

RESUMO

We evaluated the effect of AAV2- and 17-AAG (17-N-allylamino-17-demethoxygeldanamycin)-mediated upregulation of Hsp70 expression on the survival of retinal ganglion cells (RGCs) injured by optic nerve crush (ONC). AAV2-Hsp70 expression in the retina was primarily observed in the ganglion cell layer. Approximately 75% of all transfected cells were RGCs. RGC survival in AAV2-Hsp70-injected animals was increased by an average of 110% 2 weeks after the axonal injury compared with the control. The increase in cell numbers was not even across the retinas with a maximum effect of approximately 306% observed in the inferior quadrant. 17-AAG-mediated induction of Hsp70 expression has been associated with cell protection in various models of neurodegenerative diseases. We show here that a single intravitreal injection of 17-AAG (0.2 ug ul(-1)) results in an increased survival of ONC-injured RGCs by approximately 49% compared with the vehicle-treated animals. Expression of Hsp70 in retinas of 17-AAG-treated animals was upregulated approximately by twofold compared with control animals. Our data support the idea that the upregulation of Hsp70 has a beneficial effect on the survival of injured RGCs, and the induction of this protein could be viewed as a potential neuroprotective strategy for optic neuropathies.


Assuntos
Benzoquinonas/farmacologia , Dependovirus/genética , Proteínas de Choque Térmico HSP70/genética , Lactamas Macrocíclicas/farmacologia , Traumatismos do Nervo Óptico/terapia , Células Ganglionares da Retina/fisiologia , Animais , Axônios/patologia , Sobrevivência Celular , Terapia Combinada , Terapia Genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Compressão Nervosa , Regeneração Nervosa , Retina/metabolismo , Retina/patologia , Ativação Transcricional , Transdução Genética
6.
Eye (Lond) ; 28(3): 337-43, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24406416

RESUMO

PURPOSE: The purpose of this study is to quantify anterior chamber (AC) parameters and to determine the proportion of eyes with exaggerated lens vault (LV) in different subtypes of angle closure disease using anterior segment optical coherence tomography (AS-OCT). PATIENTS AND METHODS: In this prospective study, 115 eyes of 115 Iranian patients with angle closure disease were included and categorized into three groups: (1) fellow eyes of acute angle closure (AAC; 40 eyes); (2) primary angle closure glaucoma (PACG; 39 eyes); and (3) primary angle closure suspect (PACS; 36 eyes). Complete ophthalmic examination including gonioscopy, A-scan biometry, and AS-OCT were performed. Angle parameters, LV, and iris thickness (IT) were measured using AS-OCT. An exaggerated LV was defined as LV more than one-third the distance between the corneal endothelium and a line drawn to connect the nasal and temporal scleral spurs. RESULTS: Fellow eyes of AAC had the shallower AC (P=0.01), greater iris curvature (I-curve; P=0.01), and higher LV (P=0.02) as compared with PACS and PACG eyes. There was no statistically significant difference in the mean IT at 750 µm from scleral spur among the three groups (P=0.45). Exaggerated LV was found in 67.5, 35.9, and 40% of fellow eyes of AAC, PACG, and PACS, respectively, (P=0.008) with an odds ratio of 1.92 (P=0.005) for fellow vs PACG and 1.68 (P=0.01) for fellow vs PACS. CONCLUSIONS: Exaggerated LV is highly prevalent in fellow eyes of AAC. These eyes have shallower AC depth, greater I-curve, and higher LV when compared with PACG and PACS.


Assuntos
Câmara Anterior/fisiopatologia , Glaucoma de Ângulo Fechado/fisiopatologia , Doenças da Íris/fisiopatologia , Doenças do Cristalino/fisiopatologia , Biometria , Estudos Transversais , Feminino , Glaucoma de Ângulo Fechado/classificação , Gonioscopia , Humanos , Pressão Intraocular/fisiologia , Irã (Geográfico) , Doenças da Íris/diagnóstico , Doenças do Cristalino/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia de Coerência Óptica , Tonometria Ocular
7.
J Ophthalmol ; 2012: 576712, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22523651

RESUMO

Purpose. Keratolimbal allograft (KLAL) is a treatment for limbal stem cell deficiency. One disadvantage is systemic immunosuppression to avoid rejection. Our purpose was to examine the adverse effects of systemic immunosuppression in KLAL. Methods. A retrospective case review of 16 patients with KLAL who received systemic immunosuppression consisting of a corticosteroid, an antimetabolite, and/or a calcineurin inhibitor was performed. Patients were monitored for signs, symptoms, or laboratory evidence of toxicity. Results. Eleven of 16 patients (68%) experienced an adverse effect. The average age of those with adverse effects was 43.5 years and without was 31.4 years. Ten of 11 patients (91%) had resolution during mean followup of 16.4 months. No serious adverse effects occurred. The most common included anemia, hyperglycemia, elevated creatinine, and elevated liver function tests. Prednisone and tacrolimus were responsible for the most adverse effects. Patients with comorbidities were more likely to experience an adverse effect (82% versus 20%, P = 0.036). Conclusions. KLAL requires prolonged systemic immunosuppression. Our data demonstrated that systemic immunosuppression did not result in serious adverse effects in our population and is relatively safe with monitoring for toxicity. In addition, we demonstrated that adverse effects are more likely in older patients with comorbidities.

8.
Eye (Lond) ; 23(1): 89-95, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17917685

RESUMO

PURPOSE: Immediate sequential cataract surgery (ISCS) is still a controversial procedure. We compared the clinical and patient-reported outcomes of ISCS vs the usual delayed sequential cataract surgery (DSCS). METHODS: Selected patients with bilateral cataracts were assigned nonrandomly and according to their preferences to either ISCS in one session (intervention group) or DSCS over two sessions with a 2-month interval between sessions (control group). Binocular visual acuity, binocular contrast sensitivity, stereopsis, and self-reported visual function (VF-14) were measured preoperatively and postoperatively for up to 4 months after the second-eye surgery. Mann-Whitney U-test was used to compare quantitative variables, while the chi(2) and Fisher's exact tests were used for qualitative variables. RESULTS: Of the 220 eligible patients, 74 (33.6%) chose ISCS, and 137 (62.3%) selected DSCS. The remaining patients (4.1%) were allocated randomly to either group. For 2 months, the outcome measures were significantly worse in the DSCS group than in the ISCS group. However, after 4 months (2 and 4 months after second-eye surgery in the DSCS and ISCS groups, respectively) the differences became insignificant except for VF-14 (P<0.05). The mean post-operative objective measures and their differences from baseline were not significantly different between the groups. Nevertheless, postoperatively, VF-14 improved more (P<0.05) and attained a higher value (P<0.05) in the ISCS group. CONCLUSIONS: In experienced hands, with stringent patient selection criteria and with a strict aseptic protocol, ISCS can safely provide a more rapid rehabilitation of VF than DSCS.


Assuntos
Extração de Catarata/métodos , Catarata/complicações , Transtornos da Visão/cirurgia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Catarata/fisiopatologia , Catarata/psicologia , Comportamento de Escolha , Sensibilidades de Contraste/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Cuidados Pós-Operatórios , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Transtornos da Visão/etiologia , Acuidade Visual/fisiologia
9.
Eur J Ophthalmol ; 18(2): 191-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18320510

RESUMO

PURPOSE: To report on the efficacy and safety of combined phacoemulsification and an Ahmed valve glaucoma drainage implant with respect to visual acuity improvement, intraocular pressure (IOP) control, and requirement for antiglaucoma medication. METHODS: A retrospective chart review was conducted of 41 eyes (31 patients) with coexisting visually significant cataracts and uncontrolled glaucoma who had combined phacoemulsification and Ahmed valve implantation. The outcome measures were: visual acuity, IOP, antiglaucoma medication requirements, and intra- and post-operative complications. Success was categorized as absolute (IOP<21 mmHg without the need for antiglaucoma medication) and relative (IOP<21 mmHg with one or more antiglaucoma medications). Failure was considered to be an IOP<6 mmHg or IOP>21 mmHg on maximally tolerated medications or any devastating complication. RESULTS: The mean patient age was 67.3+/-5.9 years old. The mean visual acuity improved from 0.73+/-0.5 to 0.16+/-0.16 (p=0.000). The mean IOP decreased from 28.2+/-3.1 to 16.8+/-2.1 (p=0.000, 40.4%), while the number of antiglaucoma medication decreased from 2.6+/-0.66 to 1.2+/-1.4 (p=0.000). The absolute and relative success rates were 56.1% and 31.7%, respectively; 5 eyes (12.2%) were considered failures. There were no intraoperative complications; postoperative complications occurred in 8 eyes (19.5%). A hypertensive phase was detected in 12 (29.3%) eyes. CONCLUSIONS: Combined phacoemulsification and Ahmed valve glaucoma drainage implantation is a safe and effective alternative to phacotrabeculectomy in patients with coexisting cataract and refractory glaucoma.


Assuntos
Catarata/complicações , Implantes para Drenagem de Glaucoma , Glaucoma/complicações , Facoemulsificação/métodos , Idoso , Catarata/fisiopatologia , Catarata/terapia , Feminino , Glaucoma/fisiopatologia , Glaucoma/cirurgia , Humanos , Pressão Intraocular/fisiologia , Complicações Intraoperatórias , Masculino , Complicações Pós-Operatórias , Implantação de Prótese , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual/fisiologia
10.
Cornea ; 14(1): 18-25, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7712731

RESUMO

Congenital hereditary endothelial dystrophy is characterized by a diffuse bilateral corneal opacity (edema). Its inheritance has been reported to be both autosomal recessive and dominant. All our cases seemed to be autosomal recessive. There seems to be a prevalence of the recessive gene in the Iranian population. The dystrophy might be misdiagnosed as congenital glaucoma, as in several of our cases. We have operated on 37 eyes of 21 patients during the past 10 years. Our visual and anatomical success rate has been very good, with 92% clear grafts and only an 8% rejection rate, in contrast to poor prognosis that has been previously reported. In children, suture removal should be started 3 months postoperatively. Partial amblyopia was preexistent in all cases, but deep amblyopia was not common.


Assuntos
Córnea/cirurgia , Distrofias Hereditárias da Córnea/cirurgia , Endotélio Corneano/anormalidades , Endotélio Corneano/cirurgia , Ceratoplastia Penetrante , Adolescente , Adulto , Criança , Pré-Escolar , Consanguinidade , Opacidade da Córnea/congênito , Opacidade da Córnea/genética , Opacidade da Córnea/cirurgia , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Linhagem , Complicações Pós-Operatórias , Prognóstico , Técnicas de Sutura , Acuidade Visual
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