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1.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628771

RESUMO

Multiple myeloma (MM) is a cancer of plasma cells in the bone marrow characterized by bone lesions, hypercalcemia, anemia, and renal failure. Bortezomib (BTZ), a common treatment for MM, is a proteasome inhibitor that induces apoptosis in MM cells. However, high doses of BTZ can be very toxic, signifying a need for a synergistic drug combination to improve treatment efficacy. Resveratrol (RES), a phenolic compound found in grapes, has been shown to inhibit MM cell growth. We sought to identify a synergistic combination of BTZ with a RES derivative and analyze the effects on reducing viability and inducing apoptosis in human MM cells. BTZ as well as RES and its derivatives pinostilbene (PIN) and piceatannol (PIC) decreased MM cell viability in a dose- and time-dependent manner and increased expression of cleaved proapoptotic proteins poly(ADP-ribose) polymerase 1 (PARP1) and caspase-3 in a dose-dependent manner. The combination of 5 nM BTZ and 5 µM PIN was identified to have synergistic cytotoxic effects in MM RPMI 8226 cells. MM RPMI 8226 cells treated with this combination for 24 h showed increased cleaved PARP1 and caspase-3 expression and higher percentages of apoptotic cells versus cells treated with the individual compounds alone. The treatment also showed increased apoptosis induction in MM RPMI 8226 cells co-cultured with human bone marrow stromal HS-5 cells in a Transwell model used to mimic the bone marrow microenvironment. Expression of oxidative stress defense proteins (catalase, thioredoxin, and superoxide dismutase) in RPMI 8226 cells were reduced after 24 h treatment, and cytotoxic effects of the treatment were ameliorated by antioxidant N-acetylcysteine (NAC), suggesting the treatment impacts antioxidant levels in RPMI 8226 cells. Our results suggest that this combination of BTZ and PIN decreases MM cell viability synergistically by inducing apoptosis and oxidative stress in MM cells.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , Bortezomib/farmacologia , Caspase 3 , Mieloma Múltiplo/tratamento farmacológico , Antioxidantes , Resveratrol/farmacologia , Microambiente Tumoral
2.
Clin Orthop Relat Res ; 480(9): 1684-1691, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35319514

RESUMO

BACKGROUND: Femoral neck stress fractures are a common condition affecting military service members, most noticeably during basic combat training. Previous studies have investigated the risk factors for femoral neck stress fracture development in basic trainees and outcomes associated with treatment; however, few studies have focused on operatively treated femoral neck stress fracture in the military trainee. Doing so would be important not only for the military, but also providers caring for athletes, such as distance runners, who have a heightened risk for femoral neck stress fracture development. QUESTIONS/PURPOSES: (1) What proportion of US Army trainees completing basic combat training at Fort Jackson, SC, USA, who undergo surgery for femoral neck stress fracture during basic training subsequently leave military service because of the injury? (2) What factors are related to the patient or the fracture are associated with a higher likelihood of military separation? (3) What factors on the initial MRI are associated with progression of the stress fracture extent? METHODS: A retrospective study of a longitudinally maintained database of stress injuries involving basic combat trainees from a single military post was reviewed over a 3-year period. Inclusion criteria included basic trainees undergoing surgery for a femoral neck stress fracture between January 2018 and June 2020 with a minimum of 1-year follow-up. Surgery was indicated for service members with complete and tension-sided femoral neck stress fractures and those with high risk compression-sided stress fractures, generally representing fractures involving more than 50% of the femoral neck width. Over the study period, 57 service members (51% [29 of 57] women with a mean age of 24 years) underwent surgery for a femoral neck stress fracture, and all 57 had a minimum of 1-year follow-up. Identified service members underwent independent data collection including injury and radiographic parameters based on chart and imaging review. Documented fracture line progression on repeat imaging was present in 39% of service members, with a mean fracture line progression of 55% of the femoral neck width. Service members were subdivided based upon the ability to return to military service at 1 year. Univariate analysis was performed using patient and injury variables to identify factors associated with the ability to return to military service. RESULTS: Overall, 58% (33 of 57) of service members who had a femoral neck stress fracture treated surgically underwent military separation. A higher proportion of service members who demonstrated fracture line progression leading to surgical treatment remained in the military (58% [14 of 24] versus 30% [10 of 33]; odds ratio 0.3 [95% confidence interval (CI) 0.1 to 0.9]; p = 0.03). With the numbers available, we found no other patient- or fracture-related variables associated with military separation, although we suspect we may have been underpowered on some of these comparisons, in particular gender (61% [20 of 33] of individuals separated after surgery for this injury were women compared with 38% [9 of 24] who were retained; OR 2.6 [95% CI 0.9 to 7.56]; p = 0.09). The extent of osseous edema on T1-weighted imaging in association with a hip effusion demonstrated a significant positive correlation with final fracture percentage (r = 0.62; p = 0.003). CONCLUSION: Military service members with a femoral neck stress fracture initially managed nonoperatively but with progression of the fracture line requiring surgical intervention were more likely to return to military duties and complete basic combat training, suggesting that early diagnosis of femoral neck stress fractures may be associated with better functional recovery after surgical treatment. Additionally, the extent of the osseous edema on initial MRI T1-weighted imaging sequences may help predict the final extent of femoral neck stress fractures on repeat imaging. Further investigations should incorporate patient-reported outcomes and further explore factors associated with fracture progression and the inability to return to active duty or sport. LEVEL OF EVIDENCE: Level III, therapeutic study.


Assuntos
Fraturas do Colo Femoral , Fraturas de Estresse , Militares , Adulto , Edema , Feminino , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/cirurgia , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/etiologia , Fraturas de Estresse/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
3.
J Surg Orthop Adv ; 30(2): 67-72, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34181519

RESUMO

The purpose was to compare plate and screw fixation (open reduction internal fixation [ORIF]) and functional bracing (FB) of isolated humeral shaft fractures with treatment and patient-based outcomes. We performed a prospective trial of ORIF v. FB at 12 centers. Surgeons counseled patients on treatment options and a patient centered decision was made. We enrolled 179 patients, of which 6-month data was analyzed for 102 (39 female; 63 male). Forty-five were treated with ORIF and 57 with FB. We found no difference in the disability of the arm, shoulder and hand (DASH) score, visual analogue score (VAS) or elbow range of motion (ROM) at 6 months. However, 11% of the FB group developed nonunion. Complications in the ORIF group included a 2% infection and nonunion rate and 13% iatrogenic radial nerve dysfunction (RND). ORIF can be expected to result in higher union rates with the inherent risks of infection and RND. Finally, at 6 months, both groups demonstrated higher DASH scores than population norms, indicating a lack of full recovery. (Journal of Surgical Orthopaedic Advances 30(2):067-072, 2021).


Assuntos
Fixação Interna de Fraturas , Fraturas do Úmero , Placas Ósseas , Feminino , Humanos , Fraturas do Úmero/cirurgia , Úmero , Masculino , Redução Aberta , Estudos Prospectivos , Resultado do Tratamento
4.
J Surg Orthop Adv ; 30(2): 73-77, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34181520

RESUMO

Our purpose was to evaluate radiographic alignment of nonoperatively treated humerus fractures and determine if there is a critical angle associated with worse outcomes. All patients with humeral shaft fractures that were prospectively followed as part of a larger multicenter trial were reviewed. These patients were selected for nonoperative management based on shared decision making. There were 80 patients that healed with adequate data. The receiver operating characteristic (ROC) had best fit with a sagittal radiographic angle of 10° (AUC: 0.731) and coronal angle of 15° (AUC: 0.580) at 1-year follow-up. We found increased or worse disabilities of the arm, shoulder and hand (DASH) scores with > 10° sagittal alignment or > 15° of coronal alignment. Poor DASH scores were observed at angles lower than previously accepted for nonoperative treatment. These findings are useful in decision making and patient guidance. (Journal of Surgical Orthopaedic Advances 30(2):073-077, 2021).


Assuntos
Fraturas do Úmero , Fixação Interna de Fraturas , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/terapia , Úmero , Resultado do Tratamento
5.
Hum Reprod ; 35(11): 2548-2555, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33057600

RESUMO

STUDY QUESTION: Do donor oocyte recipients benefit from preimplantation genetic testing for aneuploidy (PGT-A)? SUMMARY ANSWER: PGT-A did not improve the likelihood of live birth for recipients of vitrified donor oocytes, but it did avoid embryo transfer in cycles with no euploid embryos. WHAT IS KNOWN ALREADY: Relative to slow freeze, oocyte vitrification has led to increased live birth from cryopreserved oocytes and has led to widespread use of this technology in donor egg IVF programs. However, oocyte cryopreservation has the potential to disrupt the meiotic spindle leading to abnormal segregation of chromosome during meiosis II and ultimately increased aneuploidy in resultant embryos. Therefore, PGT-A might have benefits in vitrified donor egg cycles. In contrast, embryos derived from young donor oocytes are expected to be predominantly euploid, and trophectoderm biopsy may have a negative effect relative to transfer without biopsy. STUDY DESIGN, SIZE, DURATION: This is a paired cohort study analyzing donor oocyte-recipient cycles with or without PGT-A performed from 2012 to 2018 at 47 US IVF centers. PARTICIPANTS/MATERIALS, SETTING, METHODS: Vitrified donor oocyte cycles were analyzed for live birth as the main outcome measure. Outcomes from donors whose oocytes were used by at least two separate recipient couples, one couple using PGT-A (study group) and one using embryos without PGT-A (control group), were compared. Generalized estimating equation models controlled for confounders and nested for individual donors contributing to both PGT-A and non-PGT-A cohorts, enabling a single donor to serve as her own control. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 1291 initiated recipient cycles from 223 donors were analyzed, including 262 cycles with and 1029 without PGT-A. The median aneuploidy rate per recipient was 25%. Forty-three percent of PGT-A cycles had only euploid embryos, whereas only 12.7% of cycles had no euploid embryos. On average 1.09 embryos were transferred in the PGT-A group compared to 1.38 in the group without PGT-A (P < 0.01). Live birth occurred in 53.8% of cycles with PGT-A versus 55.8% without PGT-A (P = 0.44). Similar findings persisted in cumulative live birth from per recipient cycle. LIMITATIONS, REASONS FOR CAUTION: Pooled clinical data from 47 IVF clinics introduced PGT-A heterogeneity as genetic testing were performed using different embryology laboratories, PGT-A companies and testing platforms. WIDER IMPLICATIONS OF THE FINDINGS: PGT-A testing in donor oocyte-recipient cycles does not improve the chance for live birth nor decrease the risk for miscarriage in the first transfer cycle but does increase cost and time for the patient. Further studies are required to test if our findings can be applied to the young infertility patient population using autologous oocytes. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aneuploidia , Resultado da Gravidez , Estudos de Coortes , Feminino , Testes Genéticos , Humanos , Oócitos , Gravidez , Estudos Retrospectivos
6.
Anticancer Drugs ; 31(8): 806-818, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32304407

RESUMO

Multiple myeloma is a blood cell cancer and can cause symptoms such as bone loss and fatigue. Recent studies have shown that the bone marrow microenvironment may mediate tumor proliferation, drug resistance, and migration of the multiple myeloma cells. Synthetic triterpenoids have been used for the treatment of cancer due to their antiproliferative and anti-inflammatory effects. The objective of this study is to examine the effect of 2-cyano-3, 12 dioxoolean-1,9-dien-28-oic acid (CDDO) derivatives on human multiple myeloma cells. Three CDDO derivatives, such as CDDO-methyl ester, CDDO-trifluroethyl amide, and CDDO-imidazolide (Im), were tested on the growth of human multiple myeloma cells. Our results show that all CDDO derivatives decrease the viability of multiple myeloma cells in a dose- and time-dependent manner, with CDDO-Im being the most potent. CDDO-Im was selected to investigate whether its inhibitory effect on multiple myeloma cell growth is due to cell cycle arrest and induction of apoptosis. The results suggest that CDDO-Im may inhibit cell cycle progression in the G0/G1 phase and induce the intrinsic apoptotic pathway. The effect of CDDO-Im on multiple myeloma cells was evaluated in a Transwell model using myeloma cells co-culturing with human HS-5 stromal cells to simulate the bone marrow microenvironment in vitro. The results showed that CDDO-Im induced multiple myeloma cell apoptosis in the presence of HS-5 cells, albeit to a lower extent than in multiple myeloma cells cultured alone. In conclusion, our data suggest that CDDO-Im inhibits the growth of multiple myeloma cells, either cultured alone or co-cultured with bone marrow stromal cells, through the induction of apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Células Estromais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Antineoplásicos/química , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Humanos , Imidazóis/química , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Células Estromais/metabolismo , Células Estromais/patologia , Células Tumorais Cultivadas
7.
Bioorg Med Chem ; 28(23): 115815, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33091850

RESUMO

In this article, we report our efforts towards improving in vitro human clearance in a series of 5-azaquinazolines through a series of C4 truncations and C2 expansions. Extensive DMPK studies enabled us to tackle high Aldehyde Oxidase (AO) metabolism and unexpected discrepancies in human hepatocyte and liver microsomal intrinsic clearance. Our efforts culminated with the discovery of 5-azaquinazoline 35, which also displayed exquisite selectivity for IRAK4, and showed synergistic in vitro activity against MyD88/CD79 double mutant ABC-DLBCL in combination with the covalent BTK inhibitor acalabrutinib.


Assuntos
Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Inibidores de Proteínas Quinases/metabolismo , Quinazolinas/química , Aldeído Oxidase/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Cães , Estabilidade de Medicamentos , Meia-Vida , Hepatócitos/metabolismo , Humanos , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Ratos , Relação Estrutura-Atividade
8.
J Surg Orthop Adv ; 29(3): 135-140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33044152

RESUMO

The purpose is to evaluate hip fractures due to gunshot wounds (GSW) to the hip, which are treated surgically, and the complications. Patients who sustained a low velocity GSW with fracture to the femoral head/neck and intertrochanteric/peritrochantric region at three Level 1 Trauma Centers were eligible. There were 69 patients (63 males-91%), with an average age of 29 (18-60). Nine patients had orthopaedic surgical site infections. There were 6 nonunions, 4 patients with hardware failure, 2 cases of avascular necrosis (AVN), 3 patients with post traumatic arthritis (PTA) and 20 patients with heterotopic ossification (HO). There was no significant difference found regarding fracture site or type of fixation with regards to complications. This represents the largest study of surgically treated GSW to the hip. Of patients studied, 61% sustained additional GSW. These injuries are not benign; the main complications being infection and heterotopic ossification. (Journal of Surgical Orthopaedic Advances 29(3):135-140, 2020).


Assuntos
Fraturas do Quadril , Ferimentos por Arma de Fogo , Adulto , Cabeça do Fêmur , Fixação Interna de Fraturas , Fraturas do Quadril/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Ferimentos por Arma de Fogo/complicações , Ferimentos por Arma de Fogo/cirurgia
9.
Reprod Biomed Online ; 38(5): 711-723, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30922557

RESUMO

RESEARCH QUESTION: How does oocyte cohort size affect IVF treatment outcomes? DESIGN: Retrospective cohort analysis of 10,193 fresh autologous oocyte retrievals among good-prognosis patients <35 years from 2009 to 2015. The primary outcome was live birth from a fresh transfer; secondary outcomes included cumulative live birth potential from the retrieved cohort and frequency of severe ovarian hyperstimulation syndrome (OHSS). RESULTS: Live birth per fresh transfer increased as the oocyte cohort increased up to 11-15 oocytes, then plateaued. Beyond 15 oocytes, live birth rates from fresh transfer did not decrease, even at the highest oocyte yields. When accounting for the availability of cryopreserved high-quality supernumerary blastocysts, the cumulative number of potential live births per retrieval continued to increase as oocyte yield increased. Rates of severe OHSS increased rapidly with increasing cohort size above 7-10 oocytes when final oocyte maturation was triggered with human chorionic gonadotrophin (HCG), up to nearly 7% of HCG-triggered retrievals of >25 oocytes, but when triggered with gonadotrophin-releasing hormone (GnRH) agonist the severe OHSS rate remained relatively low and stable at approximately 1% even among retrievals of the largest oocyte cohorts. CONCLUSIONS: Live birth rates per fresh embryo transfer are highest among cycles with retrieval of 11 or more oocytes. Larger cohorts are not associated with any decline in fresh transfer birth rates. Total potential births per retrieval continue to increase as the number of retrieved oocytes increases. Rates of OHSS remain relatively low after retrieval of large oocyte cohorts if final maturation is triggered with GnRH agonist rather than HCG.


Assuntos
Fertilização in vitro/estatística & dados numéricos , Recuperação de Oócitos/estatística & dados numéricos , Taxa de Gravidez , Adulto , Blastocisto , Criopreservação , Feminino , Humanos , Síndrome de Hiperestimulação Ovariana/etiologia , Indução da Ovulação/efeitos adversos , Gravidez , Estudos Retrospectivos
11.
J Surg Orthop Adv ; 26(1): 33-39, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28459422

RESUMO

There are no data-supported recommendations on how proximal is too proximal for retrograde nailing (RGN). At six level 1 trauma centers, patients with femur fractures within the proximal one-third of the femur treated with RGN were included. This article describes a proximal segment capture ratio (PSCR) and nail segment capture ratio to evaluate RGN of proximal fractures. The study included 107 patients. The average follow-up was 44 weeks. There were two nonunions and three malunions. There was no significant difference between PSCR of 0.3 or less and need for secondary procedures or time to full weight bearing (p>.05). In this study, a smaller (< 0.3) PSCR was not associated with an increased number of complications. A higher Orthopaedic Trauma Association classification was predictive of malunion and increased time to union. These data demonstrate that retrograde nailing is safe and effective for the treatment of supraisthmal femur fractures.


Assuntos
Pinos Ortopédicos , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas/métodos , Fraturas Mal-Unidas/epidemiologia , Fraturas não Consolidadas/epidemiologia , Acidentes por Quedas , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Pedestres , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Suporte de Carga , Adulto Jovem
12.
Angew Chem Int Ed Engl ; 56(47): 14883-14887, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28926175

RESUMO

Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt- or osmium-based) allowed for the formation of THF rings with either trans or cis stereoselectivity. Fragment union using a modified Julia reaction then enabled the synthesis of an advanced synthetic intermediate containing the EF and G rings of the target.

13.
Anal Chem ; 87(1): 754-9, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25457985

RESUMO

A novel approach is described for the quantitative bioanalysis of drugs in blood samples by ionization of the analytes collected on solid-phase microextraction (SPME) fibers by mass spectrometry (MS). The technique combines the attractive features of SPME microsampling using minimal sample volumes with the speed, selectivity, and sensitivity capabilities of MS detection. The method reported in this study involved generating gas-phase ions directly from SPME fibers without the need for any additional sample preparation or chromatographic separation; the entire process was completed within 5 min. Traditionally, analytes extracted by SPME fibers are desorbed by washing with suitable solvents followed by a transfer into a sample vial and subsequent liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis to quantify the amount of analyte extracted and thereby determining the analyte concentration in the matrix. These sample preparation steps are completely eliminated by inserting the SPME fiber directly into the MS. Physiologically relevant concentrations of metoprolol and propranolol in blood samples were measured over several orders of magnitude down to concentration levels of 10 ng/mL. This preliminary assessment of direct SPME-MS showed high sensitivity (ng/mL), acceptable reproducibility (<30%), and lack of carryover. This novel approach simplifies current bioanalytical procedures providing time and cost savings. It demonstrates considerable potential for qualitative and quantitative pharmaceutical bioanalysis as well as other areas of challenging environmental and food analysis.


Assuntos
Cromatografia Líquida/métodos , Metoprolol/sangue , Propranolol/sangue , Microextração em Fase Sólida/instrumentação , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Ratos
14.
Prog Med Chem ; 54: 1-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25727702

RESUMO

In the past 20 years, cancer therapeutics has undergone a paradigm shift away from the traditional cytotoxic drugs towards the targeting of proteins intimately involved in driving the cancer phenotype. The poster child for this alternative approach to the treatment of cancer is imatinib, a small-molecule kinase inhibitor designed to target chronic myeloid leukaemia driven by the BCR-ABL translocation in a defined patient population. The improvement in survival achieved by treatment of this patient cohort with imatinib is impressive. Thus, the aim is to provide efficacy but with low toxicity. The role of the medicinal chemist in oncology drug discovery is now closely aligned with the role in most other therapeutic areas with high-throughput and/or fragment-based screening, structure-based design, selectivity, pharmacokinetic optimisation and pharmacodynamic biomarker modulation, all playing a familiar part in the process. In this chapter, we selected four areas in which compounds are either approved drugs or in clinical trials. These are chaperone inhibitors, kinase inhibitors, histone deacetylase inhibitors and inhibitors of protein-protein interactions. Even within these areas, we have been selective, particularly for kinase inhibitors, and our aim has been to exemplify newer approaches and novel aspects of medicinal chemistry.


Assuntos
Neoplasias/tratamento farmacológico , Animais , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Chaperonas Moleculares/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico
15.
J Neuroeng Rehabil ; 12: 1, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25557982

RESUMO

: Technological advancements have led to the development of numerous wearable robotic devices for the physical assistance and restoration of human locomotion. While many challenges remain with respect to the mechanical design of such devices, it is at least equally challenging and important to develop strategies to control them in concert with the intentions of the user.This work reviews the state-of-the-art techniques for controlling portable active lower limb prosthetic and orthotic (P/O) devices in the context of locomotive activities of daily living (ADL), and considers how these can be interfaced with the user's sensory-motor control system. This review underscores the practical challenges and opportunities associated with P/O control, which can be used to accelerate future developments in this field. Furthermore, this work provides a classification scheme for the comparison of the various control strategies.As a novel contribution, a general framework for the control of portable gait-assistance devices is proposed. This framework accounts for the physical and informatic interactions between the controller, the user, the environment, and the mechanical device itself. Such a treatment of P/Os--not as independent devices, but as actors within an ecosystem--is suggested to be necessary to structure the next generation of intelligent and multifunctional controllers.Each element of the proposed framework is discussed with respect to the role that it plays in the assistance of locomotion, along with how its states can be sensed as inputs to the controller. The reviewed controllers are shown to fit within different levels of a hierarchical scheme, which loosely resembles the structure and functionality of the nominal human central nervous system (CNS). Active and passive safety mechanisms are considered to be central aspects underlying all of P/O design and control, and are shown to be critical for regulatory approval of such devices for real-world use.The works discussed herein provide evidence that, while we are getting ever closer, significant challenges still exist for the development of controllers for portable powered P/O devices that can seamlessly integrate with the user's neuromusculoskeletal system and are practical for use in locomotive ADL.


Assuntos
Extremidade Inferior , Aparelhos Ortopédicos , Próteses e Implantes , Desenho de Prótese/métodos , Atividades Cotidianas , Eletromiografia , Marcha , Humanos , Locomoção
16.
Trauma Case Rep ; 50: 100979, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38357291

RESUMO

Background: Although bone morphogenetic proteins (BMPs) are used as an adjunct to promote healing, they may have unintended effects such as heterotopic ossification (HO). The literature is limited regarding the effect of using off-label BMPs for femur fractures. Case presentation: We report two outcomes after off-label use of BMPs for the treatment of femur fractures and propose a possible explanation for the difference. Conclusions: BMPs are critical osteoinductive factors in injured bone and muscle that facilitate bony healing. However, it may be important to recognize the potentially negative effects of adding BMP to bone graft material in certain cases to stimulate bone repair. We hope this case series helps surgeons consider the risks and benefits of using BMP for femur fractures, and therefore to decide with caution when BMP is indicated.

17.
Polymers (Basel) ; 16(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38399893

RESUMO

As the use of Natural Fiber Reinforced Polymers (NFRPs) become increasingly popular in the built environment, steps in established workflows, including molding and transportation, continue to impose constraints on what is possible in the material's fabrication process. This research builds on previous studies of moldless fiber composites using tailored fiber placement (TFP) as a fabrication method. By integrating compliant folding mechanisms into the flat preform to give shape to the final desired geometry this research replaces all dependencies on molds and formworks during the resin curing process with programmed formal deformations. The desired geometry is digitally simulated from its two-dimensional state into its resultant three-dimensional state and then subsequently structurally analyzed. The flat pack components are material efficient and can be transported flat to the site for their final assembly into their programmed geometry. This form is locked into its bent active state through the use of a simple drawstring that can later be removed to revert the form back into its flat state. This method is demonstrated through the digital fabrication of a stool where flat-packed elements can be deployed into elegant solutions that embody structure, material, and form simultaneously.

18.
JSES Int ; 8(2): 278-281, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38464442

RESUMO

Background: Biceps tenodesis is a common treatment for pathologies involving the long head of the biceps brachii. Given variations in surgical approach, focus has been placed on the location of the tenodesis to maintain appropriate length-tension relationship. The purpose of this study is to assess for variations in the tunnel placement in subpectoral biceps tenodesis procedures and correlation of tunnel position with patient-reported outcomes. Methods: This is a retrospective case series of outcomes as a function of tunnel location with open subpectoralis biceps tenodesis. The location of the biceps tenodesis tunnel was measured on postoperative Grashey radiographs. Correlation between the tenodesis tunnel and postoperative American Shoulder and Elbow Surgeons (ASES) score and Visual Analog Scale (VAS) was assessed. Results: 31 patients were included in the study with an average follow-up of 17 months. The overall tunnel position from the superior edge of the greater tuberosity ranged from 4.20 cm to 12.61 cm, with an average of 7.46 cm. Final ASES score and VAS were 84.5 and 1.2, respectively. There was only weak correlation between both ASES score and tunnel position (r = -0.12) and VAS and tunnel position (r = -0.23). Discussion: Subpectoralis biceps tenodesis continues to be a viable treatment option for biceps and superior labral pathology. There remains no consensus on tenodesis location, and this study found no significant difference between tunnel location and patient-reported outcomes. Therefore, it is likely that a range of tenodesis locations exists in which favorable clinical results are achieved, explaining the numerous recommendations on tunnel placement.

19.
Front Pharmacol ; 15: 1325196, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510655

RESUMO

Multiple myeloma (MM) is characterized by the accumulation of malignant plasma cells preferentially in the bone marrow. Currently, emerging chemotherapy drugs with improved biosafety profiles, such as immunomodulatory agents and protease inhibitors, have been used in clinics to treat MM in both initial therapy or maintenance therapy post autologous hematopoietic stem cell transplantation (ASCT). We previously discovered that caffeic acid phenethyl ester (CAPE), a water-insoluble natural compound, inhibited the growth of MM cells by inducing oxidative stress. As part of our continuous effort to pursue a less toxic yet more effective therapeutic approach for MM, the objective of this study is to investigate the potential of CAPE for in vivo applications by using magnetic resonance imaging (MRI)-capable superparamagnetic iron oxide nanoparticles (IONP) as carriers. Cyclo (Arg-Gly-Asp-D-Phe-Cys) (RGD) is conjugated to IONP (RGD-IONP/CAPE) to target the overexpressed αvß3 integrin on MM cells for receptor-mediated internalization and intracellular delivery of CAPE. A stable loading of CAPE on IONP can be achieved with a loading efficiency of 48.7% ± 3.3% (wt%). The drug-release studies indicate RGD-IONP/CAPE is stable at physiological (pH 7.4) and basic pH (pH 9.5) and subject to release of CAPE at acidic pH (pH 5.5) mimicking the tumor and lysosomal condition. RGD-IONP/CAPE causes cytotoxicity specific to human MM RPMI8226, U266, and NCI-H929 cells, but not to normal peripheral blood mononuclear cells (PBMCs), with IC50s of 7.97 ± 1.39, 16.75 ± 1.62, and 24.38 ± 1.71 µM after 72-h treatment, respectively. Apoptosis assays indicate RGD-IONP/CAPE induces apoptosis of RPMI8226 cells through a caspase-9 mediated intrinsic pathway, the same as applying CAPE alone. The apoptogenic effect of RGD-IONP/CAPE was also confirmed on the RPMI8226 cells co-cultured with human bone marrow stromal cells HS-5 in a Transwell model to mimic the MM microenvironment in the bone marrow. In conclusion, we demonstrate that water-insoluble CAPE can be loaded to RGD-IONP to greatly improve the biocompatibility and significantly inhibit the growth of MM cells in vitro through the induction of apoptosis. This study paves the way for investigating the MRI-trackable delivery of CAPE for MM treatment in animal models in the future.

20.
Fertil Steril ; 119(1): 29-35, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36460523

RESUMO

OBJECTIVE: To evaluate potential variation in the euploid blastocyst rate and live birth rate (LBR) per single frozen euploid blastocyst transfer, among 4 unique United States reproductive genetics laboratories. Analyses were limited to blastocysts derived from vitrified donor oocytes, to minimize variation in oocyte quality. DESIGN: Retrospective cohort study from 2016 to 2020. SETTING: Donor Egg Bank Database. PATIENT(S): Patients undergoing in vitro fertilization with donor oocytes. We excluded patients with uterine factor, male factor, or surgically extracted sperm. Only healthy women <34 years old were accepted as oocyte donors. INTERVENTION(S): Next generation sequencing platforms for chromosomal analysis MAIN OUTCOME MEASURE(S): Euploid blastocyst rate and LBR per euploid transfer. Secondary outcomes included the rate of aneuploidy, mosaic calls, biochemical pregnancy loss, and miscarriage rate. RESULT(S): A total of 2,633 embryos were included. Four laboratories had >200 embryos tested. Euploid blastocyst rate was significantly higher in laboratory A (73.6%) vs. B (63.3%), C (60.9%), and D (52.3%). Mosaic rate was significantly lower for Laboratories B (2.8%) and C (5.5%) vs. Laboratories A (9.9%) and D (11.5). The LBR was significantly higher in laboratory A (58.73%) vs. laboratory D (47.3%). There were no significant differences in the implantation or miscarriage rate among laboratories. CONCLUSION(S): In this large study, controlling for oocyte quality, some preimplantation genetic testing for aneuploidy (PGT-A) laboratories report a significantly higher euploid blastocyst rate with concurrent higher LBR. This type of comparison is important as it provides insight into the role of the PGT-A process in outcomes. Further research is needed to evaluate the differences in laboratory techniques and bioinformatic algorithms accounting for variable outcomes across PGT-A laboratories.


Assuntos
Aborto Espontâneo , Diagnóstico Pré-Implantação , Gravidez , Humanos , Masculino , Feminino , Coeficiente de Natalidade , Aborto Espontâneo/diagnóstico , Aborto Espontâneo/genética , Estudos Retrospectivos , Diagnóstico Pré-Implantação/métodos , Laboratórios , Nascido Vivo , Sêmen , Testes Genéticos/métodos , Aneuploidia , Blastocisto , Oócitos
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