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1.
J Gastrointest Surg ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38834105

RESUMO

PURPOSE: Total pancreatectomy with islet autotransplantation (TPIAT) is an effective treatment for patients with chronic pancreatitis (CP) when other interventions are unsuccessful. CP has many etiologies including heredity. Metabolic and pain relief outcomes following TPIAT are presented among patients with a genetic CP etiology when compared to those with a nongenetic etiology in a large cohort of patients who underwent this procedure at our center. METHODS: A retrospective analysis was performed of 237 TPIAT patients from 2006 to 2023. We analyzed the differences in patients with genetic (n = 56) versus nongenetic (n = 181) CP etiologies in terms of pre-TPIAT factors including patient characteristics and disease state, results from the isolation process, and outcomes such as long-term glycemic and pain control. RESULTS: Patients with genetic CP underwent TPIAT at a significantly younger age (32.3 years vs 41.3 years nongenetic, p < 0.0001) and endured symptoms for a significantly longer period (10 vs 6 years, p < 0.01). A significantly lower mass of islets was isolated from patients with genetic CP (p < 0.01), which increased with body mass index in both groups. Despite lower yields, genetic CP patients maintained metabolic function like nongenetic CP patients, as indicated by insulin independence and C-peptide, blood glucose, and hemoglobin A1c levels after TPIAT. Posttransplant narcotic usage and pain scores significantly decreased compared to pre-TPIAT, and more genetic CP patients were pain free and narcotic free post-TPIAT. CONCLUSIONS: Our data validate TPIAT as a beneficial procedure for patients enduring CP of genetic etiology. Pain that is inevitably recurrent after minor interventions due to the nature of the disease and favorable TPIAT outcomes should be considered in the decision to perform early TPIAT in cases of genetic CP.

2.
Curr Opin Organ Transplant ; 29(3): 175-179, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38506730

RESUMO

PURPOSE OF REVIEW: Normothermic regional perfusion (NRP) is a novel procurement technique for donation after circulatory death (DCD) in the United States. It was pioneered by cardiothoracic surgery programs and is now being applied to abdominal-only organ donors by abdominal transplant programs. RECENT FINDINGS: Liver and kidney transplantation from thoracoabdominal NRP (TA-NRP) donors in the United States was found to have lower rates of delayed kidney graft function and similar graft and patient survival versus recipients of cardiac super rapid recovery (SRR) DCD donors. The excellent outcomes with NRP have prompted the expansion of NRP technology to abdominal transplant programs. SUMMARY: Excellent early outcomes with liver and kidney transplantation have prompted the growth of NC-NRP procurement for abdominal-only DCD donors across the US, and now requires standardization of technical and nontechnical aspects of this procedure.


Assuntos
Transplante de Rim , Transplante de Fígado , Perfusão , Doadores de Tecidos , Humanos , Perfusão/tendências , Perfusão/métodos , Perfusão/efeitos adversos , Estados Unidos , Transplante de Rim/tendências , Transplante de Rim/efeitos adversos , Transplante de Fígado/tendências , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Doadores de Tecidos/provisão & distribuição , Sobrevivência de Enxerto , Resultado do Tratamento , Preservação de Órgãos/tendências , Preservação de Órgãos/métodos , Obtenção de Tecidos e Órgãos/tendências
3.
Surg J (N Y) ; 8(1): e69-e79, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35252562

RESUMO

Introduction Lip augmentation with dermal filler is rising in popularity. There are generally minimal side effects that are mild and transient. However, long-term complications may occur and include lumps, bumps, nodules, or granulomas. To better understand this uncommon but challenging outcome, we aim to perform a thorough systematic review of the published literature related to nodule or granuloma formation after cosmetic soft tissue augmentation of the lips. Methods A search of published literature was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines in April 2021 and included PubMed, ScienceDirect, Embase, Google Scholar, and Cochrane databases. The Medical Subject Headings (MeSH) terms used included the following terms: "lip filler," "hyaluronic acid," "lip injection," "lip augmentation," "silicone," "poly-L-lactic acid," "calcium hydroxyapatite," "polymethylmethacrylate," "complications," "reaction," "granuloma," and "nodule." All studies were reviewed by two independent reviewers. Any discrepancies were resolved by a third reviewer. Results The initial search for filler-related nodules or granulomas yielded 2,954 articles and 28 were included in the final analysis containing 66 individual cases of lip nodules. All but one patient was female. The mean age was 50 years. Nodules presented on average 35.2 months or 2.9 years after initial treatment. Thirty-seven nodules underwent histological analysis, the majority of which identified the presence of a foreign-body granuloma. Silicone was the most reported filler used followed by hyaluronic acid. Most cases resolved following multiple treatments including oral antibiotics or steroids followed by surgical excision. Conclusion Understanding the sequelae of lip augmentation with filler products allows clinicians to provide safe and effective treatment. Nodules that present months to years following dermal treatment may represent a foreign-body granuloma. A combination of oral antibiotics, intralesional or oral steroids, and surgical excision successfully treated the majority of cases in our study.

4.
Facial Plast Surg ; 38(3): 285-292, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34983070

RESUMO

Facial cosmetic surgery trends are evolving in the current climate of the coronavirus disease 2019 (COVID-19) pandemic. The aim of this study was to evaluate public interest in elective facial plastic surgery during the COVID-19 pandemic including the period of the COVID-19 vaccine distribution using Google Trends. A Google Trends analysis was completed using popular terms related to facial cosmetic surgery and procedures from March 2017 to August 2021. Three stages were identified (baseline, pre-COVID-19 vaccine distribution, and post-COVID-19 vaccine distribution). Descriptive statistics were calculated and two-tailed t-tests were performed between the pre-vaccine and the post-vaccine phases. Linear regression analysis was also performed to determine percent deflection of search terms. There was significantly greater interest in facial aesthetic procedure search terms, except for tear trough filler, during the post-COVID-19 vaccine phase compared with the pre-COVID-19 vaccine phase. There was greater interest in lower facial procedure interest during this phase compared with upper facial procedures (p-value = 0.0011). The search terms with the greatest deflection percentage during the post-vaccine phase were lip filler, brow lift, and lip flip. There continues to be high demands of facial plastic surgery and procedures despite COVID-19 pandemic.


Assuntos
COVID-19 , Cirurgia Plástica , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Pandemias/prevenção & controle , Ferramenta de Busca
5.
Facial Plast Surg ; 38(3): 228-239, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34192769

RESUMO

There is significant variation in treatment parameters when treating the infraorbital region. Thorough knowledge of these pertinent factors, choice of the optimal filling material, and proper understanding of the anatomy of this unforgiving region will contribute to a safe, effective, and natural result. We aim to conduct a systematic review of published literature related to soft tissue fillers of the tear trough and infraorbital region. A search of published literature was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and included PubMed, Embase, and Science Direct databases. The Medical Subject Headings (MeSH) terms used were "tear trough" OR "infraorbital" AND "dermal filler" OR "hyaluronic acid" OR "poly-L-lactic acid" OR "calcium hydroxyapatite" OR "Restylane" OR "Radiesse" OR "Perlane" OR "Juvéderm" OR "Belotero." Different combinations of these key terms were used. The initial search identified 526 articles. Six additional articles were identified through references. Two-hundred twenty-five duplicates were removed. A total of 307 studies were screened by title and abstract and 258 studies were eliminated based on inclusion and exclusion criteria. Forty-nine articles underwent full-text review. The final analysis included 23 articles. Patient satisfaction was high, and duration of effect ranged from 8 to 12 months. Restylane was most commonly used. Injection technique varied, but generally involved placing filler pre-periosteally, deep to orbicularis oculi muscle, anterior to the inferior orbital rim via serial puncture or retrograde linear threading with a 30-gauge needle. Topical anesthetic was most commonly used. Side effects were generally mild and included bruising, edema, blue-gray dyschromia, and contour irregularities. Nonsurgical correction of the tear trough deformity with soft tissue filler is a minimally invasive procedure with excellent patient satisfaction with long-lasting effects. It is essential to have a fundamental understanding of the relevant anatomy and ideal injection technique to provide excellent patient outcomes and prevent serious complications.


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Envelhecimento da Pele , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/uso terapêutico , Pálpebras/cirurgia , Humanos , Rejuvenescimento
6.
Facial Plast Surg Aesthet Med ; 24(1): 27-33, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33847531

RESUMO

Importance: Although nasal bones are the most common type of facial fracture given their natural projection and vulnerability to trauma, there is a paucity of data on its trends. Objective: To report on the trends and costs associated with open and closed nasal bone fractures across the United States. Methods: A retrospective analysis from 2006 to 2014 was conducted of the Nationwide Emergency Department Sample by using the International Classification of Disease, Ninth Revision codes for closed and open nasal bone fractures (802.0 and 802.1) presenting to emergency departments (ED). Trend analysis of total number and rate of visits, discharges, admissions, and associated costs were conducted. Results: Data from 1,253,399.741 records were collected. The total number of ED visits decreased by 2.05% for both open and closed nasal fractures from 2006 to 2014 whereas their associated costs increased (p < 0.001 and p < 0.05 for closed and open nasal fractures). Notably, open fractures were consistently costlier whereas closed fractures had a greater percent-increase in costs (76.65%). Conclusions and Relevance: This study identified a significant rise in nasal fracture costs, which can be reduced via use of cheaper diagnostic modalities and cost-effective endoscopic procedures.


Assuntos
Osso Nasal/lesões , Fraturas Cranianas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Custos de Cuidados de Saúde/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas Cranianas/diagnóstico , Fraturas Cranianas/economia , Fraturas Cranianas/terapia , Estados Unidos/epidemiologia
7.
Facial Plast Surg ; 38(3): 250-259, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34666405

RESUMO

Tear trough deformity is a popular target for the treatment with filler injections. The side effects are generally mild and transient. However, delayed complications may occur. We aim to perform a thorough systematic review of the published literature related to delayed complications after tear trough filler injections. A search of published literature was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in June 2021 and included PubMed, ScienceDirect, and Embase databases. The Medical Subject Headings (MeSH) terms used included the following terms: delayed complications, nodules, granulomas, swelling, discoloration, dermal filler, hyaluronic acid (HA), polyacrylamide, calcium hydroxyapatite (CaHA), poly-L-lactic acid (PLLA), eyelid, periorbital, periocular, and tear trough. Twenty-eight articles consisting of 52 individual cases were included in the final analysis. 98% (51/52) of patients were female and had an average age of 48.3 years. HA was the most reported product (71.2%, 37/52), followed by PLLA (4/52, 7.7%), and CaHA (4/52, 7.7%). The most common delayed complication with any dermal filler was swelling (42.3%, 22/52) followed by lumps or nodules (25.0%, 13/52). Xanthelasma-like reaction (17.3%, 9/52), migration (7.7%, 4/52), discoloration (3%, 3/52) also occurred. The average time of onset of any complication was 16.8 months with xanthelasma-like reaction appearing soonest (mean: 10 months) and discoloration appearing latest (mean: 52 months). Most swelling cases were caused by HA. Semi-permanent fillers such as PMMA and synthetic fillers such as PLLA were more likely to be associated with lumps and nodules than other complications. It is important that clinicians who perform tear trough augmentation with dermal fillers have a thorough understanding of the risks of the procedure to diagnose and manage them promptly as well as provide patients with accurate information regarding the potential adverse effects.


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/uso terapêutico , Durapatita/efeitos adversos , Edema/etiologia , Pálpebras , Feminino , Humanos , Ácido Hialurônico/uso terapêutico , Injeções , Masculino , Pessoa de Meia-Idade
8.
Facial Plast Surg ; 38(1): 32-39, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34500488

RESUMO

Effective management of the upper nasal vault is based on a thorough preoperative analysis and detailed understanding of the requisite principles and techniques utilized to modify the anatomic structures in this region. The surgeon must equally consider form and function when performing manipulation of the upper nasal vault. Special considerations apply when managing this anatomic region via an endonasal or closed approach. A review of this topic is presented with a focus on techniques as they apply to the endonasal rhinoplasty patient.


Assuntos
Rinoplastia , Humanos , Nariz/cirurgia
10.
JAMA Surg ; 156(11): 1051-1057, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34495291

RESUMO

Importance: Acuity circles (AC) liver allocation policy was implemented to eliminate donor service area geographic boundaries from liver allocation and to decrease variability in median Model of End-stage Liver Disease (MELD) score at transplant and wait list mortality. However, the broader sharing of organs was also associated with more flights for organ procurements and higher costs associated with the increase in flights. Objective: To determine whether the costs associated with liver acquisition changed after the implementation of AC allocation. Design, Setting, and Participants: This single-center cost comparison study analyzed fees associated with organ acquisition before and after AC allocation implementation. The cost data were collected from a single transplant institute with 2 liver transplant centers, located 30 miles apart, in different donation service areas. Cost, recipient, and transportation data for all cases that included fees associated with liver acquisition from July 1, 2019, to October 31, 2020, were collected. Exposures: Primary liver offer acceptance with associated organ procurement organization or charter flight fees. Main Outcomes and Measures: Specific fees (organ acquisition, surgeon, import, and charter flight fees) and total fees per donor were collected for all accepted liver donors with at least 1 associated fee during the study period. Results: Of 213 included donors, 171 were used for transplant; 90 of 171 (52.6%) were male, and the median (interquartile range) age of donors was 41.0 (30.0-52.8) years in the pre-AC period and 36.9 (24.0-48.8) years in the post-AC period. There was no significant difference in the post-AC compared with pre-AC period in median (range) MELD score (24 [8-40] vs 25 [6-40]; P = .27) or median (range) match run sequence (15 [1-3951] vs 10 [1-1138]; P = .31), nor in mean (SD) distance traveled (155.83 [157.00] vs 140.54 [144.33] nautical miles; P = .32) or percentage of donors requiring flights (58.5% [69 of 118] vs 56.8% [54 of 95]; P = .82). However, costs increased significantly in the post-AC period: total cost increased 16% per accepted donor (mean [SD] of $52 966 [13 278] vs $45 725 [9300]; P < .001) and 55% per declined donor (mean [SD] of $15 865 [3942] vs $10 217 [4853]; P < .001). Contributing factors included more than 2-fold increases in the proportions of donors incurring import fees (31.4% [37 of 118] vs 12.6% [12 of 95]; P = .002) and surgeon fees (19.5% [23 of 118] vs 9.5% [9 of 95]; P = .05), increased acquisition fees (10% increase; mean [SD] of $43 860 [3266] vs $39 980 [2236]; P < .001), and increased flight expenses (43% increase; mean [SD] of $12 904 [6066] vs $9049 [5140]; P = .002). Conclusions and Relevance: The unintended consequences of implementing broader sharing without addressing organ acquisition fees to account for increased importation between organ procurement organizations must be remedied to contain costs and ensure viability of transplant programs.


Assuntos
Doença Hepática Terminal/cirurgia , Honorários e Preços , Política de Saúde/economia , Obtenção de Tecidos e Órgãos/economia , Adulto , Custos e Análise de Custo , Doença Hepática Terminal/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Seleção de Pacientes , Listas de Espera , Adulto Jovem
11.
Clin Transplant ; 35(7): e14331, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33914373

RESUMO

Non-contrast pelvic computed tomography (CT) can detect severe iliac artery calcifications that present technical contraindications to kidney transplantation (TCT). We screened 454 asymptomatic patients with a history of any of the following: hemodialysis >10 years, diabetes mellitus >20 years, coronary artery disease (CAD) with percutaneous or surgical interventions, carotid disease, diabetes with below-/above-knee amputations, and heart-kidney transplantation candidacy. Patients with normal dorsalis pedis and/or tibialis posterior pulses were not screened. A total of 8.4% had severe calcifications with TCT; CT determined laterality for implantation in 13.9%. No patients with the following characteristics were classified as TCT: age <40 years, hemodialysis >10 years, carotid arterial disease, prior lower extremity amputation, or heart-kidney transplantation candidacy. CAD was associated with TCT in univariate though not multivariate analysis. Limiting screening to patients >40 years, with DM >20 years, or with CAD, 9.8% had a TCT and CT determined transplant laterality in 14.2%. Screening for severe iliac artery calcifications is useful for selected kidney transplantation candidates over age 40. It can assist with laterality choice or surgeon determination of TCT. Cost and radiation exposure risks should be weighed against the morbidity risks from unnecessary surgery.


Assuntos
Doença da Artéria Coronariana , Transplante de Rim , Adulto , Humanos , Programas de Rastreamento , Diálise Renal , Tomografia Computadorizada por Raios X
12.
Facial Plast Surg ; 37(4): 536-542, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33648015

RESUMO

There has been an increasing role in the use of injectable fillers for rejuvenation of the aging face. In this systematic review, we aim to evaluate the existing literature related to soft tissue fillers of the midface. Specifically, we focus on the non-hyaluronic acid fillers including polymethylmethacrylate (PMMA), poly-L-lactic acid (PLLA), calcium hydroxyapatite (CaHA), and autologous fat. A systematic review was conducted in November 2020 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with PubMed and Embase databases. Medical Subject Headings terms used were "cheek" OR "midface" OR "malar" and "filler" OR "poly-L-lactic acid" OR "calcium hydroxyapatite," "autologous fat" OR "polymethylmethacrylate" OR "Artefill" OR "Bellafill" OR "Radiesse" OR "Sculptra." The initial search identified 271 articles. After 145 duplicates were removed, 126 studies were screened for relevance by title and abstract. A total of 114 studies were eliminated based on inclusion and exclusion criteria. Twelve articles underwent full-text review. Seven articles were included in the final analysis consisting of four non-hyaluronic filler products: PMMA, PLLA, CaHA, autologous fat. Most patients were highly satisfied with their results. Due to the gradual volumizing effects of PMMA, PLLA, and CaHA, patient satisfaction generally improved over time. Minor adverse reactions related to treatment included bruising, swelling, and pain. Nodule formation was reported in PLLA and CaHA studies. For autologous fat, 32% of the original injection volume remained at 16 months post-treatment, which still provided clinically improved malar enhancement. Dermal fillers are an attractive treatment option for the aging face due to their high patient satisfaction, long-lasting effects, and low side-effect profile. Patients should be appropriately counseled on the delayed effects of non-HA fillers. Autologous fat is a good option in many patients with the major drawback of unpredictable longevity, which may require a secondary procedure. Future studies should examine the longevity and long-term side effects of these fillers.


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Envelhecimento da Pele , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/efeitos adversos , Durapatita , Face , Humanos , Ácido Hialurônico/efeitos adversos , Rejuvenescimento
13.
Facial Plast Surg ; 37(5): 576-584, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33634456

RESUMO

Injectable fillers represent one of the most requested minimally invasive treatments to rejuvenate the aging face, and its popularity is steadily rising. A vast majority of filler treatments are with hyaluronic acid (HA). The aim of this systematic review is to evaluate patient outcomes, safety profile, and administration techniques of various HA fillers for malar augmentation. A systematic review of the published literature was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and included PubMed, Embase, and Science Direct databases. Medical Subject Headings (MeSH) terms used were "cheek" OR "midface" OR "malar" and "filler" OR "hyaluronic acid" OR "Juvederm" OR "Restylane" OR "Perlane" OR "Belotero." The initial search identified 699 articles; 256 duplicates were removed. Additional 12 studies were identified from reference lists. A total of 455 were screened by title and abstract and 387 studies were eliminated based on criteria. Also, 68 articles underwent full-text review, and 18 articles were included in the final review and involved seven different HA formulations. Men and women from many age groups were highly satisfied with their results following HA treatment for midface augmentation up to 24 months. The most common adverse events included bruising, swelling, and tenderness, and typically lasted no more than 2 weeks. Upper cheek filler injections near the zygoma should be placed in the submuscular plane while lower cheek injections should be placed in the subcutaneous tissue. HA is an attractive choice for midface augmentation due to its high patient satisfaction, long-lasting effects, and low side-effect profile. Due to the variability in technique, level of expertise, and subjective measurements across studies, one optimal regimen could not be concluded. However, midface augmentation treatment should be personalized to each patient. Additional clinical trials are required to more conclusively determine the most appropriate approach for this procedure.


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Envelhecimento da Pele , Bochecha , Pré-Escolar , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/efeitos adversos , Face , Feminino , Humanos , Ácido Hialurônico/efeitos adversos , Masculino
14.
Transplantation ; 105(1): 225-230, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32150040

RESUMO

BACKGROUND: Uterus transplantation is a treatment for absolute uterine infertility and can be performed with living and deceased donors. Given the safety and increased utilization of robotic assistance with other gynecologic and transplant donor operations, we adopted a robot-assisted approach to donor hysterectomy. This study compared early outcomes and morbidity of the robot-assisted approach to donor hysterectomy with the traditionally performed open approach and addressed whether the robot-assisted approach is safe and offers advantages for the donor. METHODS: Our institution has performed 18 living donor hysterectomies for uterus transplantation. This retrospective review compared the last 5 cases utilizing a robot-assisted technique and vaginal extraction of the uterus graft with the first 13 cases performed with an open laparotomy technique. Demographic, intraoperative, and postoperative data were examined. RESULTS: There were no differences between the robot-assisted and the open living donor group with respect to age, body mass index, or gynecological history. Although the median operative time was shorter for the open approach (6.27 versus 10.46 h), the donors' median estimated blood loss, length of hospital stay, and length of sick leave were less with the robot-assisted approach. There was no conversion to open hysterectomy in the robot-assisted cases, and the incidence of complications was similar between the 2 groups. There was no difference in early graft function. CONCLUSIONS: These preliminary results show that robot-assisted living donor hysterectomy is feasible and safe for the donors; it allows a faster postoperative recovery and the same early graft function.


Assuntos
Histerectomia , Doadores Vivos , Procedimentos Cirúrgicos Robóticos , Útero/transplante , Adulto , Perda Sanguínea Cirúrgica , Feminino , Humanos , Histerectomia/efeitos adversos , Tempo de Internação , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Licença Médica , Texas , Fatores de Tempo , Resultado do Tratamento
15.
Chemphyschem ; 21(23): 2585-2598, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006228

RESUMO

Understanding of the structural changes during their aggregation and interaction is a prerequisite for establishing the precise clinical relevance of human islet amyloid polypeptide (hIAPP) (involved in Type-II Diabetes Mellitus) in the treatment of Alzheimer's disease stemmed from beta-amyloid (Aß). Herein, we show that the steady-state emission spectra obtained from photoluminescence (PL) simultaneously capture both the tyrosine derivative (tyrosinate) and the structure-specific intrinsic fluorescence during the aggregation of Aß and hIAPP. We observe multiple peaks in the emission spectra which exist for structure-specific intrinsic fluorescence, and use the second derivative UV-Vis spectra and the shift in the tyrosine peak as a quantitative measure of the dissimilitude in the electronic states and the fibril growth. We further applied these techniques to detect the static electric field (0, 40, 120, 200 V/cm) induced promotion and inhibition of fibrillation in Aß, hIAPP and their electric field dependent role in the fibrillation of Aß : hIAPP(1 : 1). The results were corroborated by field-emission scanning electron microscopy (FESEM), and the determinations of secondary structures by Fourier transform infrared spectroscopy (FTIR). The results indicate that the emission spectrum can be used as a sensor to detect the presence of fibrils; hence for screening potential inhibitors of amyloid fibrillation.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Fluorescência , Polipeptídeo Amiloide das Ilhotas Pancreáticas/análise , Agregação Patológica de Proteínas/diagnóstico , Tirosina/análise , Humanos , Microscopia Eletrônica de Varredura , Agregados Proteicos , Estrutura Secundária de Proteína , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
16.
Soft Matter ; 16(33): 7778-7788, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32744550

RESUMO

In a recent report, the fractal self-assembly of gold nanoparticles (AuNPs) having a directional feature was observed in the presence of visible light. Therein, the visible light, an external parameter, was suspected to be responsible for the directional feature. Herein, we investigate the intrinsic factors, the aspect size ratio p and the size a of AuNPs, in modulating the fractal characteristics of their self-assemblies. Through light scattering experiments and microscopic imaging, we demonstrate the transition of morphologies from fractal-like to cross-shaped in gold colloidal aggregates with particles having nearly spherical and ellipsoidal shapes, respectively. The transition indicates the competitive role of anisotropy and fluctuations in deciding the morphological characteristics of the aggregates. By taking noise-reduced diffusion-limited aggregation (NRDLA) as a model system, we address the shape and size induced noise of the particles in the colloidal systems which are prone to form fractal aggregates. We qualitatively relate the noise due to the particles having a distinct aspect size ratio p and size a with the noise reduction parameter m of NRDLA. The realistic nature of the experimental systems, where the particles of different p and a are present during the growth process, is incorporated by introducing the Gaussian noise reduction in diffusion-limited aggregation (DLA). The morphological phase transition in Gaussian noise reduced DLA is characterized, and its relevance for accounting the shape and size originated noise fluctuations during the fractal growth process is discussed. The results of the present study may be used for tailored applications of AuNPs in drug delivery, biomedicine, biosensing, and cancer nanotechnology.

17.
Phys Rev E ; 101(6-1): 062413, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32688470

RESUMO

The aggregation of amyloid-ß (Aß) and human islet amyloid polypeptide (hIAPP) proteins have attracted considerable attention because of their involvement in protein misfolding diseases. These proteins have mostly been investigated using atomic force microscopy, transmission electron microscopy, and fluorescence microscopy to study the directional growth of fibrils both perpendicular to and along the fibril axis. Here, we demonstrate the real-time monitoring of the directional growth of fibrils in terms of activation energy of proton transfer using an impedance spectroscopy technique. The activation energy is used to quantify the sensitivity of proton conduction to the different stages of protein aggregation. The decrement (increment) in activation energy is related to the fibril growth along (perpendicular to) the fibril axis in intrinsic protein aggregation. The entire aggregation process shows different phases of the directional growth for Aß and hIAPP, indicating different pathways for their aggregation. The activation energy for hIAPP is found to be smaller than the activation energy of Aß during the aggregation process. The oscillatory behavior of the activation energy of hIAPP reflects a rapid change in the directional growth of the protofilaments of hIAPP. The results indicate higher aggregation propensity of Aß than hIAPP. In the presence of resveratrol, hIAPP exhibits slower aggregation compared to Aß. Methods of this study may in general be used to reveal the modulated aggregation pathway of proteins in the presence of different ligands.


Assuntos
Peptídeos beta-Amiloides/química , Elétrons , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Agregados Proteicos , Humanos , Cinética
18.
Ann Surg ; 272(3): 411-417, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32657928

RESUMO

OBJECTIVE: We report the results of the first 20 uterus transplants performed in our institution. SUMMARY BACKGROUND DATA: Uterus transplantation (UTx) aims at giving women affected by absolute uterine-factor infertility the possibility of carrying their own pregnancy. UTx has evolved from experimental to an established surgical procedure. METHODS: The Dallas Uterus Transplant Study (DUETS) program started in 2016. The uterus was transplanted in orthotopic position with vascular anastomoses to the external iliac vessels and removed when 1 or 2 live births were achieved. Immunosuppression lasted only for the duration of the uterus graft. RESULTS: Twenty women, median age 29.7 years, enrolled in the study, with 10 in phase 1 and 10 in phase 2. All but 2 recipients had a congenital absence of the uterus. Eighteen recipients received uteri from living donors and 2 from deceased donors. In phase 1, 50% of recipients had a technically successful uterus transplant, compared to 90% in phase 2. Four recipients with a technical success in phase 1 have delivered 1 or 2 babies, and the fifth recipient with a technical success is >30 weeks pregnant. In phase 2, 2 recipients have delivered healthy babies and 5 are pregnant. CONCLUSIONS: UTx is a unique type of transplant; whose only true success is a healthy child birth. Based on results presented here, involving refinement of the surgical technique and donor selection process, UTx is now an established solution for absolute uterine-factor infertility.


Assuntos
Seleção do Doador/métodos , Fertilidade/fisiologia , Infertilidade Feminina/cirurgia , Doadores Vivos , Transplante de Órgãos/métodos , Útero/transplante , Adulto , Feminino , Seguimentos , Humanos , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
20.
Soft Matter ; 16(12): 3143-3153, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32159545

RESUMO

Human amylin is an intrinsically disordered protein believed to have a central role in Type-II diabetes mellitus (T2DM). The formation of intermediate oligomers is a seminal event in the eventual self-assembled fibril structures of amylin. However, the recent experimental investigations have shown the presence of different self-assembled (oligomers, protofilaments, and fibrils) and aggregated structures (amorphous aggregates) of amylin formed during its aggregation. Here, we show that amylin under diffusion-limited conditions leads to fractal self-assembly. The pH and solvent sensitive fractal self-assemblies of amylin were observed using an optical microscope. Confocal microscopy and scanning electron microscopy (SEM) with energy dispersion X-ray analysis (EDAX) were used to confirm the fractal self-assembly of amylin in water and PBS buffer, respectively. The fractal characteristics of the self-assemblies and the aggregates formed during the aggregation of amylin under different pH conditions were investigated using laser light scattering. The hydropathy and the docking study indicated the interactions between the anisotropically distributed hydrophobic residues and polar/ionic residues on the solvent-accessible surface of the protein as the crucial interaction hot-spots for driving the self-assembly and aggregation of human amylin. The simultaneous presence of various self-assemblies of human amylin was observed through different microscopy techniques. The present study may help in designing different fractal-like nanomaterials with potential applications in drug delivery, sensing, and tissue engineering.


Assuntos
Amiloide/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Agregados Proteicos , Amiloide/ultraestrutura , Fractais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polipeptídeo Amiloide das Ilhotas Pancreáticas/ultraestrutura , Modelos Moleculares , Conformação Proteica
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