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1.
Plast Reconstr Surg Glob Open ; 12(5): e5797, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38741601

RESUMO

Microsurgery is a complex subspecialty requiring fine manual dexterity and a thorough understanding of microsurgical techniques, requiring years of training to reach proficiency. On a global scale, trainees may not have access to a longitudinal microsurgery curriculum and instead attend brief courses to learn microsurgical techniques, limiting their ability to practice the nuances of microsurgery. There remains a gap in global microsurgical education for trainees to have consistent educational exposure. This article presents a novel and easy to use software-based microsurgical system for virtual microsurgical teaching. In doing so, this system provides a free-of-cost and highly accessible avenue to deliver consistent microsurgical education worldwide.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38606549

RESUMO

PtRu alloys have been recognized as the state-of-the-art catalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). However, their applications in DMFCs are still less efficient in terms of both catalytic activity and durability. Rare earth (RE) metals have been recognized as attractive elements to tune the catalytic activity, while it is still a world-class challenge to synthesize well-dispersed Pt-RE alloys. Herein, we developed a novel hydrogen-assisted magnesiothermic reduction strategy to prepare a highly dispersed carbon-supported lutetium-doped PtRu catalyst with ultrafine nanoclusters and atomically dispersed Ru sites. The PtRuLu catalyst shows an outstanding high electrochemical surface area (ECSA) of 239.0 m2 gPt-1 and delivers an optimized MOR mass activity and specific activity of 632.5 mA mgPt-1 and 26 A cmPt-2 at 0.4 V vs saturated calomel electrode (SCE), which are 3.6 and 3.5 times of commercial PtRu-JM and an order higher than PtLu, respectively. These novel catalysts have been demonstrated in a high-temperature direct methanol fuel cell running in a temperature range of 180-240 °C, achieving a maximum power density of 314.3 mW cm-2. The AC-STEM imaging, in situ ATR-IR spectroscopy, and DFT calculations disclose that the high performance is resulted from the highly dispersed PtRuLu nanoclusters and the synergistic effect of the atomically dispersed Ru sites with PtRuLu nanoclusters, which significantly reduces the CO* intermediates coverage due to the promoted water activation to form the OH* to facilitate the CO* removal.

3.
Med ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38670112

RESUMO

BACKGROUND: The gut mycobiome is closely linked to health and disease; however, its role in the progression of type 2 diabetes mellitus (T2DM) remains obscure. Here, a multi-omics approach was employed to explore the role of intestinal fungi in the deterioration of glycemic control. METHODS: 350 participants without hypoglycemic therapies were invited for a standard oral glucose tolerance test to determine their status of glycemic control. The gut mycobiome was identified through internal transcribed spacer sequencing, host genetics were determined by genotyping array, and plasma metabolites were measured with untargeted liquid chromatography mass spectrometry. FINDINGS: The richness of fungi was higher, whereas its dissimilarity was markedly lower, in participants with T2DM. Moreover, the diversity and composition of fungi were closely associated with insulin sensitivity and pancreatic ß-cell functions. With the exacerbation of glycemic control, the co-occurrence network among fungus taxa became increasingly complex, and the complexity of the interaction network was inversely associated with insulin sensitivity. Mendelian randomization analysis further demonstrated that the Archaeorhizomycetes class, Fusarium genus, and Neoascochyta genus were causally linked to impaired glucose metabolism. Furthermore, integrative analysis with metabolomics showed that increased 4-hydroxy-2-oxoglutaric acid, ketoleucine, lysophosphatidylcholine (20:3/0:0), and N-lactoyl-phenylalanine, but decreased lysophosphatidylcholine (O-18:2), functioned as key molecules linking the adverse effect of Fusarium genus on insulin sensitivity. CONCLUSIONS: Our study uncovers a strong association between disturbance in gut fungi and the progression of T2DM and highlights the potential of targeting the gut mycobiome for the management of T2DM. FUNDINGS: This study was supported by MOST and NSFC of China.

4.
J Vis Exp ; (205)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38526116

RESUMO

Small animal transplant models are indispensable for organ tolerance studies investigating feasible therapeutic interventions in preclinical studies. Rat liver transplantation (LTx) protocols typically use an orthotopic model where the recipients' native liver is removed and replaced with a donor liver. This technically demanding surgical procedure requires advanced micro-surgical skills and is further complicated by lengthy anhepatic and lower body ischemia times. This prompted the development of a less complicated heterotopic method that can be performed faster with no anhepatic or lower body ischemia time, reducing post-surgery stress for the recipient animal. This heterotopic LTx protocol includes two main steps: excising the liver from the donor rat and transplanting the whole liver into the recipient rat. During the excision of the donor liver, the surgeon ligates the supra-hepatic vena cava (SHVC) and hepatic artery (HA). On the recipient side, the surgeon removes the left kidney and positions the donor liver with the portal vein (PV), infra-hepatic vena cava (IHVC), and bile duct facing the renal vessels. Further, the surgeon anastomoses the recipient's renal vein end to end with the IHVC of the liver and arterializes the PV with the renal artery using a stent. A hepaticoureterostomy is utilized for biliary drainage by anastomosing the bile duct to the recipient's ureter, permitting the discharge of bile via the bladder. The average duration of the transplantation was 130 min, cold ischemia duration was around 35 min, and warm ischemia duration was less than 25 min. Hematoxylin and eosin histology of the auxiliary liver from syngeneic transplants showed normal hepatocyte structure with no significant parenchymal alterations 30 days post-transplant. In contrast, 8-day post-transplant allogeneic graft specimens demonstrated extensive lymphocytic infiltration with a Banff Schema rejection activity index score of 9. Therefore, this LTx method facilitates a low morbidity rejection model alternative to orthotopic LTx.


Assuntos
Transplante de Fígado , Ratos , Animais , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Fígado/patologia , Anastomose Cirúrgica/métodos , Isquemia/patologia , Aloenxertos
5.
J Reconstr Microsurg ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395058

RESUMO

BACKGROUND: Perforator dissection and flap elevation are routinely performed for microsurgical reconstruction; however, there is a steep learning curve to mastering these technical skills. Though live porcine models have been utilized as microsurgical training models, significant drawbacks limit their use. We recently developed a latex-perfused, nonliving, porcine abdomen perforator dissection simulation and described its anatomic similarity to the human deep inferior epigastric artery flap. The purpose was to assess the change in resident confidence in performing key operative steps of flap elevation and perforator dissection and obtain feedback on model realism and utility. METHODS: Seventeen plastic and reconstructive surgery resident physicians (postgraduate years 1-6) at a single institution participated in a perforator dissection session utilizing the simulation model. Each resident completed pre- and postactivity surveys to assess interval change in confidence in operating. The postactivity survey also asked residents to answer questions regarding their perception of the model's anatomic and surgical realism and utility in microsurgical training. RESULTS: Following a practice session using the latex-perfused, nonliving porcine abdomen, resident confidence was significantly increased in performing all key operative steps and the procedure overall (p = 0.001). All residents (n = 17, 100%) believed the model would improve "trainees' ability to perform perforator dissection in the operating room." Perforator, fascial, and pedicle anatomy were reported to be "Very" similar to human anatomy, with a median Likert score (MLS) of 4. Additionally, six out of the eight surgical steps were noted to be "Very" realistic, with only "Flap Design" and "Fascial Closure" found to be "Moderately" realistic with an MLS of 3. CONCLUSION: The latex-infused porcine abdominal model is a novel, realistic simulation for microsurgical trainee perforator dissection practice. This model offers a suitable substitute for perforator dissection practice, as its implementation within a microsurgery training course improves resident comfort and confidence.

6.
Int J Mol Sci ; 25(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38338887

RESUMO

Vascularized composite allotransplantation (VCA) represents a promising reconstructive solution primarily conducted to improve quality of life. However, tissue damage caused by cold-ischemia (CI) storage prior to transplant represents a major factor limiting widespread application. This study investigates the addition of the novel free radical scavenger PrC-210 to UW Organ Preservation Solution (UW Solution) to suppress CI-induced skeletal muscle injury in a rat hind limb amputation model. Lewis rats received systemic perfusion of UW solution +/- PrC-210 (0 mM control, 10 mM, 20 mM, 30 mM, or 40 mM), followed by bilateral transfemoral amputation. Limbs were stored in 40 mL of the same perfusate at 4 °C for 48 h. Muscle punch biopsies were taken at set times over the 48 h cold-storage period and analyzed for caspase-3,7 activity, cytochrome C levels, and qualitative histology. A single 15 s perfusion of PrC-210-containing UW Solution conferred a dose-dependent reduction in CI-induced muscle cell death over 48 h. In the presence of PrC-210, muscle cell mitochondrial cytochrome C release was equivalent to 0 h controls, with profound reductions in the caspase-3,7 apoptotic marker that correlated with limb histology. PrC-210 conferred complete prevention of ROS-induced mitochondrial lysis in vitro, as measured by cytochrome C release. We conclude that the addition of 30 mM PrC210 to UW Solution conferred the most consistent reduction in CI limb damage, and it warrants further investigation for clinical application in the VCA setting.


Assuntos
Aloenxertos Compostos , Diaminas , Soluções para Preservação de Órgãos , Traumatismo por Reperfusão , Compostos de Sulfidrila , Ratos , Animais , Sequestradores de Radicais Livres , Caspase 3 , Aloenxertos Compostos/patologia , Citocromos c , Qualidade de Vida , Ratos Endogâmicos Lew , Glutationa/farmacologia , Alopurinol/farmacologia , Insulina/farmacologia , Isquemia , Preservação de Órgãos , Temperatura Baixa , Traumatismo por Reperfusão/patologia , Rafinose , Adenosina
8.
J Reconstr Microsurg ; 40(1): 23-29, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37023768

RESUMO

BACKGROUND: Perforator dissection and flap elevation are routinely performed for microsurgical reconstruction; however, there is a steep learning curve to mastering these technical skills. Though live porcine models have been utilized as a microsurgical training model, there are significant drawbacks that limit their use, including cost, limited ability for repetition, and obstacles associated with animal care. Here we describe the creation of a novel perforator dissection model using latex augmented non-living porcine abdominal walls. We provide anatomic measurements that demonstrate valuable similarities and differences to human anatomy to maximize microsurgical trainee practice. METHODS: Six latex-infused porcine abdomens were dissected based on the deep cranial epigastric artery (DCEA). Dissection was centered over the abdominal wall mid-segment between the second and fourth nipple line. Dissection steps included exposure of lateral and medial row perforators, incision of anterior rectus sheath with perforator dissection, and dissection of DCEA pedicle. DCEA pedicle and perforator measurements were compared with deep inferior epigastric artery (DIEA) data in the literature. RESULTS: An average of seven perforators were consistently identified within each flap. Assembly of the model was performed quickly and allowed for two training sessions per specimen. Porcine abdominal walls demonstrate similar DCEA pedicle (2.6 ± 0.21 mm) and perforator (1.0 ± 0.18 mm) size compared with a human's DIEA (2.7 ± 0.27 mm, 1.1 ± 0.85 mm). CONCLUSION: The latex-infused porcine abdominal model is a novel, realistic simulation for perforator dissection practice for microsurgical trainees. Impact on resident comfort and confidence within a microsurgical training course is forthcoming.


Assuntos
Parede Abdominal , Microcirurgia , Retalho Perfurante , Animais , Humanos , Parede Abdominal/cirurgia , Parede Abdominal/irrigação sanguínea , Artérias Epigástricas/cirurgia , Artérias Epigástricas/anatomia & histologia , Látex , Microcirurgia/educação , Retalho Perfurante/irrigação sanguínea , Suínos
9.
J Plast Reconstr Aesthet Surg ; 88: 57-65, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37952438

RESUMO

BACKGROUND: The hypothesis of this study was that trigeminal nerve stimulation (TNS) or peripheral nerve stimulation (PNS) could improve functional outcomes of peripheral nerve injury in a rat forelimb model when compared to control rats not receiving electrical stimulation (ES). While PNS is known to improve outcomes after nerve surgery, the role of TNS has not been explored. METHODS: Lewis rats were trained to perform a reach and grasp task before receiving a 2 mm gap repair of the ulnar and median nerves and randomized into four treatment groups: (1) sham injury, (2) nerve injury with sham ES, (3) nerve injury with PNS, and (4) nerve injury with TNS. Functional motor (median pull force and percent success in motor task) and sensory metrics (forelimb paw withdrawal thresholds) were collected both pre-injury and throughout rehabilitation. Nerves stained using Gomori's trichrome were assessed quantitatively and qualitatively. RESULTS: The sham ES group did not recover their pre-injury baseline functional outcomes. In contrast, the TNS and PNS groups fully recovered following injury, with no difference in functional outcomes between the pre-injury baseline and the final week of rehabilitation (P > 0.05, all). Histomorphology results demonstrated no quantitative difference, but qualitative differences in architecture were evident. CONCLUSIONS: Electrical stimulation of the trigeminal nerve or the injured nerve improved the functional outcomes of nerve regeneration in rodents. Histomorphology results of nerves from the TNS group support the proposed central mechanisms. This is an important step in translating this therapy as an adjunct, non-invasive treatment for high, mixed nerve injuries in humans.


Assuntos
Traumatismos dos Nervos Periféricos , Roedores , Animais , Ratos , Estimulação Elétrica/métodos , Membro Anterior , Nervo Mediano , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/cirurgia , Ratos Endogâmicos Lew , Recuperação de Função Fisiológica/fisiologia , Nervo Trigêmeo
11.
J Reconstr Microsurg ; 39(8): 648-654, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37040796

RESUMO

BACKGROUND: The value of a fully trained microsurgeon dedicated to a laboratory setting at an academic institution is largely unknown. Microsurgery training lacks a national standard despite its highly complicated nature. Our study aims to evaluate the impact of a single laboratory-dedicated microsurgeon on the microsurgical training of integrated plastic surgery residents and collaborative efforts in research. METHOD: We devised a three-faceted microsurgical training curriculum, including a collaborative multi-institutional microsurgery course, novel high-fidelity simulator models, and a dedicated microsurgeon. We cataloged grant funding achieved through support to other divisions' protocols. Time, in hours, spent on training and the number of anastomoses completed with the microsurgical educator in a laboratory setting over a 4-year period (2017-2021) were evaluated. Resident independence scores were collected from attending microsurgeons to quantify the translation of microsurgical training. RESULTS: Purchasing and maintenance costs of rats in our rodent facility decreased by $16,533.60 as 198 rats were replaced by our models. The residents who participated in our novel microsurgical training program were able to independently perform anastomoses in the OR by their postgraduate year 6. Additionally, the surgical support offered by our laboratory-dedicated microsurgeon led to a total of $24,171,921 in grant funding between 2017 and 2020. CONCLUSION: Hiring an expert microsurgical educator to train residents in a laboratory has proved promising in accelerating microsurgical mastery. Novel training modules, alternatives to animal models, save resources in housing and animal costs. The addition of a research-oriented-microsurgeon has improved collaborative efforts to advance a range of surgical fields.


Assuntos
Internato e Residência , Ratos , Animais , Competência Clínica , Currículo , Microcirurgia/métodos , Custos e Análise de Custo
12.
Bioelectron Med ; 9(1): 9, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118841

RESUMO

BACKGROUND: Vagus nerve stimulation (VNS) is a FDA approved therapy regularly used to treat a variety of neurological disorders that impact the central nervous system (CNS) including epilepsy and stroke. Putatively, the therapeutic efficacy of VNS results from its action on neuromodulatory centers via projections of the vagus nerve to the solitary tract nucleus. Currently, there is not an established large animal model that facilitates detailed mechanistic studies exploring how VNS impacts the function of the CNS, especially during complex behaviors requiring motor action and decision making. METHODS: We describe the anatomical organization, surgical methodology to implant VNS electrodes on the left gagus nerve and characterization of target engagement/neural interface properties in a non-human primate (NHP) model of VNS that permits chronic stimulation over long periods of time. Furthermore, we describe the results of pilot experiments in a small number of NHPs to demonstrate how this preparation might be used in an animal model capable of performing complex motor and decision making tasks. RESULTS: VNS electrode impedance remained constant over months suggesting a stable interface. VNS elicited robust activation of the vagus nerve which resulted in decreases of respiration rate and/or partial pressure of carbon dioxide in expired air, but not changes in heart rate in both awake and anesthetized NHPs. CONCLUSIONS: We anticipate that this preparation will be very useful to study the mechanisms underlying the effects of VNS for the treatment of conditions such as epilepsy and depression, for which VNS is extensively used, as well as for the study of the neurobiological basis underlying higher order functions such as learning and memory.

13.
J Reconstr Microsurg ; 39(9): 734-742, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36931312

RESUMO

BACKGROUND: Preparation of the recipient vessels is a crucial step in autologous breast reconstruction, with limited opportunity for resident training intraoperatively. The Blue-Blood-infused porcine chest wall-a cadaveric pig thorax embedded in a mannequin shell, connected to a saline perfusion system-is a novel, cost-effective ($55) simulator of internal mammary artery (IMA) dissection and anastomosis intended to improve resident's comfort, safety, and expertise with all steps of this procedure. The purpose of this study was to assess the effect of the use of this chest wall model on resident's confidence in performing dissection and anastomosis of the IMA, as well as obtain resident's and faculty's perspectives on model realism and utility. METHODS: Plastic surgery residents and microsurgery faculty at the University of Wisconsin were invited to participate. One expert microsurgeon led individual training sessions and performed as the microsurgical assistant. Participants anonymously completed surveys prior to and immediately following their training session to assess their change in confidence performing the procedure, as well as their perception of model realism and utility as a formal microsurgical training tool on a five-point scale. RESULTS: Every participant saw improvement in confidence after their training session in a minimum of one of seven key procedural steps identified. Of participants who had experience with this procedure in humans, the majority rated model anatomy and performance of key procedural steps as "very" or "extremely" realistic as compared with humans. 100% of participants believed practice with this model would improve residents' ability to perform this operation in the operating room and 100% of participants would recommend this model be incorporated into the microsurgical training curriculum. CONCLUSION: The Blue-Blood porcine chest wall simulator increases trainee confidence in performing key steps of IMA dissection and anastomosis and is perceived as valuable to residents and faculty alike.


Assuntos
Internato e Residência , Treinamento por Simulação , Humanos , Suínos , Animais , Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Tórax
14.
Hepatology ; 78(5): 1384-1401, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631007

RESUMO

BACKGROUND AND AIMS: HCC is a highly heterogeneous disease that is caused largely by genomic copy number variations. Herein, the mechanistic and therapeutically targeted role of vacuolar protein sorting 72 homologue (VPS72), a novel copy number variation cis-driven gained gene identified by genome-wide copy number variation and transcriptome analyses in HCC, is not well understood. APPROACH AND RESULTS: First, overexpression of VPS72 enhanced the initiation and progression of HCC in vitro and in vivo . Mechanistically, VPS72 interacted with the oncoproteins MYC and actin-like 6A (ACTL6A) and promoted the formation of the ACTL6A/MYC complex. Furthermore, ACTL6A regulated VPS72 protein stability by weakening the interaction between tripartite motif containing 21 (TRIM21) and VPS72. Thus, the interaction between VPS72 and ACTL6A enhanced the affinity of MYC for its target gene promoters and promoted their transcription, thereby contributing to HCC progression, which was inhibited by adeno-associated virus serotype 8 (AAV8)-mediated short hairpin RNA (shRNA) against VPS72. CONCLUSIONS: This study reveals the molecular mechanism of ACTL6A/VPS72/MYC in HCC, providing a theoretical basis and therapeutic target for this malignancy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Actinas/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Cromossômicas não Histona/genética , Progressão da Doença , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Repressoras/metabolismo
15.
J Clin Transl Hepatol ; 11(2): 490-501, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-36643047

RESUMO

Biliary tract cancers (BTCs) are a group of malignant neoplasms that have recently increased in incidence and have a poor prognosis. Surgery is the only curative therapy. However, most patients are only indicated for palliative therapy because of advanced-stage disease at diagnosis and rapid progression. The current first-line treatment for advanced BTC is gemcitabine and cisplatin chemotherapy. Nonetheless, many patients develop resistance to this regimen. Over the years, few chemotherapy regimens have managed to improve the overall survival of patients. Accordingly, novel therapies such as targeted therapy have been introduced to treat this patient population. Extensive research on tumorigenesis and the genetic profiling of BTC have revealed the heterogenicity and potential target pathways, such as EGFR, VEGF, MEK/ERK, PI3K and mTOR. Moreover, mutational analysis has documented the presence of IDH1, FGFR2, HER2, PRKACA, PRKACB, BRAF, and KRAS gene aberrations. The emergence of immunotherapy in recent years has expanded the treatment landscape for this group of malignancies. Cancer vaccines, adoptive cell transfer, and immune checkpoint inhibitors have been extensively investigated in trials of BTC. Therefore, patient stratification and a combination of various therapies have become a reasonable and important clinical strategy to improve patient outcomes. This review elaborates the literature on combined treatment strategies for advanced BTC from the past few years and ongoing clinical trials to provide new inspiration for the treatment of advanced BTC.

16.
PLoS One ; 17(10): e0275564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36227902

RESUMO

APRIL (A proliferation inducing ligand) and BLyS (B Lymphocyte Stimulator) are two critical survival factors for B lymphocytes and plasma cells, the main source of alloantibody. We sought to characterize the specific effects of these cytokines in a kidney transplant model of antibody mediated rejection (AMR). We engineered APRIL-/- and BLyS-/- Lewis rats using CRISPR/Cas9. APRIL-/- and BLyS-/- rats were sensitized with Brown Norway (BN) blood (complete MHC mismatch). Twenty-one days following sensitization, animals were harvested and collected tissues were analyzed using flow cytometry, ELISPOT, and immunohistochemistry. Flow cross match and a 3 day mixed lymphocyte reaction (MLR) was performed to assess donor specific antibody (DSA) production and T-cell proliferation, respectively. Sensitized dual knock out Lewis rats (APRIL-/-/BLyS-/-) underwent kidney transplantation and were sacrificed on day 7 post-transplant. Sensitized BLyS-/- had significant decreases in DSA and cell proliferation compared to WT and APRIL-/- (p<0.02). Additionally, BLyS-/- rats had a significant reduction in IgG secreting cells in splenic marginal zone B lymphocytes, and in cell proliferation when challenged with alloantigen compared to WT and APRIL-/-. Transplanted APRIL-/-/BLyS-/- rodents had significantly less DSA and antibody secreting cells compared to WT (p<0.05); however, this did not translate into a significant difference in AMR seen between groups. In summary, our studies suggest that APRIL and BLyS play a greater role in DSA generation rather than AMR, highlighting the role of cellular pathways that regulate AMR.


Assuntos
Transplante de Rim , Animais , Fator Ativador de Células B , Proliferação de Células , Rejeição de Enxerto , Imunoglobulina G , Isoanticorpos , Isoantígenos , Ratos , Ratos Endogâmicos Lew , Roedores , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral
17.
Front Immunol ; 13: 833243, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812402

RESUMO

Introduction: Normothermic ex vivo liver perfusion (NEVLP) is an organ preservation method that allows liver graft functional assessment prior to transplantation. One key component of normothermic perfusion solution is an oxygen carrier to provide oxygen to the liver to sustain metabolic activities. Oxygen carriers such as red blood cells (RBCs) or hemoglobin-based oxygen carriers have an unknown effect on the liver-resident immune cells during NEVLP. In this study, we assessed the effects of different oxygen carriers on the phenotype and function of liver-resident immune cells. Methods: Adult Lewis rat livers underwent NEVLP using three different oxygen carriers: human packed RBCs (pRBCs), rat pRBCs, or Oxyglobin (a synthetic hemoglobin-based oxygen carrier). Hourly perfusate samples were collected for downstream analysis, and livers were digested to isolate immune cells. The concentration of common cytokines was measured in the perfusate, and the immune cells underwent phenotypic characterization with flow cytometry and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The stimulatory function of the liver-resident immune cells was assessed using mixed lymphocyte reactions. Results: There were no differences in liver function, liver damage, or histology between the three oxygen carriers. qRT-PCR revealed that the gene expression of nuclear factor κ light chain enhancer of activated B cells (NF-kB), Interleukin (IL-1ß), C-C motif chemokine ligand 2 (CCL2), C-C motif chemokine ligand 7 (CCL7), and CD14 was significantly upregulated in the human pRBC group compared with that in the naive, whereas the rat pRBC and Oxyglobin groups were not different from that of naive. Flow cytometry demonstrated that the cell surface expression of the immune co-stimulatory protein, CD86, was significantly higher on liver-resident macrophages and plasmacytoid dendritic cells perfused with human pRBC compared to Oxyglobin. Mixed lymphocyte reactions revealed increased allogeneic T-cell proliferation in the human and rat pRBC groups compared to that in the Oxyglobin group. Conclusions: Liver-resident immune cells are important mediators of rejection after transplantation. In this study, we show that the oxygen carrier used in NEVLP solutions can affect the phenotype of these liver-resident immune cells. The synthetic hemoglobin-based oxygen carrier, Oxyglobin, showed the least amount of liver-resident immune cell activation and the least amount of allogeneic proliferation when compared to human or rat pRBCs. To mitigate liver-resident immune cell activation during NEVLP (and subsequent transplantation), Oxyglobin may be an optimal oxygen carrier.


Assuntos
Transplante de Fígado , Oxigênio , Animais , Quimiocinas/metabolismo , Hemoglobinas/metabolismo , Ligantes , Fígado/patologia , Transplante de Fígado/métodos , Oxigênio/metabolismo , Perfusão/métodos , Ratos , Ratos Endogâmicos Lew
18.
Front Neurosci ; 16: 828593, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495044

RESUMO

As technology continues to improve within the neuroprosthetic landscape, there has been a paradigm shift in the approach to amputation and surgical implementation of haptic neural prosthesis for limb restoration. The Osseointegrated Neural Interface (ONI) is a proposed solution involving the transposition of terminal nerves into the medullary canal of long bones. This design combines concepts of neuroma formation and prevention with osseointegration to provide a stable environment for conduction of neural signals for sophisticated prosthetic control. While this concept has previously been explored in animal models, it has yet to be explored in humans. This anatomic study used three upper limb and three lower limb cadavers to assess the clinical feasibility of creating an ONI in humans. Anatomical measurement of the major peripheral nerves- circumference, length, and depth- were performed as they are critical for electrode design and rerouting of the nerves into the long bones. CT imaging was used for morphologic bone evaluation and virtual implantation of two osseointegrated implants were performed to assess the amount of residual medullary space available for housing the neural interfacing hardware. Use of a small stem osseointegrated implant was found to reduce bone removal and provide more intramedullary space than a traditional implant; however, the higher the amputation site, the less medullary space was available regardless of implant type. Thus the stability of the endoprosthesis must be maximized while still maintaining enough residual space for the interface components. The results from this study provide an anatomic basis required for establishing a clinically applicable ONI in humans. They may serve as a guide for surgical implementation of an osseointegrated endoprosthesis with intramedullary electrodes for prosthetic control.

19.
Biomolecules ; 11(7)2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34356678

RESUMO

Allograft kidney transplantation, which triggers host cellular- and antibody-mediated rejection of the kidney, is a major contributor to kidney damage during transplant. Here, we asked whether PrC-210 would suppress damage seen in allograft kidney transplant. Brown Norway (BN) rat kidneys were perfused in situ (UW Solution) with or without added 30 mM PrC-210, and then immediately transplanted into Lewis (LEW) rats. 20 h later, the transplanted BN kidneys and LEW rat plasma were analyzed. Kidney histology, and kidney/serum levels of several inflammation-associated cytokines, were measured to assess mismatch-related kidney pathology, and PrC-210 protective efficacy. Twenty hours after the allograft transplants: (i) significant histologic kidney tubule damage and mononuclear inflammatory cell infiltration were seen in allograft kidneys; (ii) kidney function metrics (creatinine and BUN) were significantly elevated; (iii) significant changes in key cytokines, i.e., TIMP-1, TNF-alpha and MIP-3A/CCL20, and kidney activated caspase levels were seen. In PrC-210-treated kidneys and recipient rats, (i) kidney histologic damage (Banff Scores) and mononuclear infiltration were reduced to untreated background levels; (ii) creatinine and BUN were significantly reduced; and (iii) activated caspase and cytokine changes were significantly reduced, some to background. In conclusion, the results suggest that PrC-210 could provide broadly applicable organ protection for many allograft transplantation conditions; it could protect transplanted kidneys during and after all stages of the transplantation process-from organ donation, through transportation, re-implantation and the post-operative inflammation-to minimize acute and chronic rejection.


Assuntos
Diaminas/farmacologia , Inflamação/tratamento farmacológico , Transplante de Rim/efeitos adversos , Rim/efeitos dos fármacos , Compostos de Sulfidrila/farmacologia , Adenosina , Aloenxertos , Alopurinol , Animais , Caspases/metabolismo , Creatinina/sangue , Citocinas/metabolismo , Diaminas/administração & dosagem , Sequestradores de Radicais Livres/farmacologia , Glutationa , Inflamação/patologia , Insulina , Rim/patologia , Transplante de Rim/métodos , Masculino , Mitocôndrias/efeitos dos fármacos , Soluções para Preservação de Órgãos , Rafinose , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Compostos de Sulfidrila/administração & dosagem
20.
Pathol Oncol Res ; 27: 640936, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257606

RESUMO

Tuftelin 1 (TUFT1), a protein functioning distinctively in different tissues, is reported to be elevated in several types of cancers and the elevation of TUFT1 is correlated with unfavorable clinicopathologic characteristics and poor survival. However, the involvement of TUFT1 in renal cell carcinoma (RCC) remains unknown. In the current study, we investigated the role of TUFT1 in RCC and potential underlying mechanisms. RT-PCR and Western blot analysis showed that both the mRNA and protein levels of TUFT1 were increased in primary RCC tissue and RCC cell lines. TUFT1 overexpression in RCC cells resulted in enhanced cell proliferation and migration while knockdown of TUFT1 by contrast decreased the growth and migration of the RCC cells, indicating TUFT1 expression is involved in RCC cell growth and migration. The involvement of TUFT1 in the epithelial-mesenchymal transition (EMT) of RCC cells was also determined by measuring the expression of EMT-related markers. Our data showed that TUFT1 overexpression promoted RCC cell EMT progression while knockdown of TUFT1 suppressed such process. Further signaling pathway inhibition assay revealed that TUFT1-induced RCC cell growth, migration and EMT was significantly suppressed by PI3K inhibitor, but not JNK or MEK inhibitors. In addition, TUFT1 overexpression enhanced the AKT phosphorylation, a key member of the PI3K signaling pathway, while PI3K inhibitor suppressed such process. Taken together, our study showed that TUFT1 expression was elevated in RCC and such elevation promoted the proliferation, migration and EMT of RCC cells in vitro, through PI3K/AKT signaling pathway. The findings of our current study imply that TUFT1 is involved in RCC tumorigenesis, and it may serve as a biomarker for RCC diagnosis and a potential target for RCC treatment.


Assuntos
Carcinoma de Células Renais/patologia , Movimento Celular , Proliferação de Células , Proteínas do Esmalte Dentário/metabolismo , Regulação Neoplásica da Expressão Gênica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Proteínas do Esmalte Dentário/genética , Transição Epitelial-Mesenquimal , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Fosfatidilinositol 3-Quinases/genética , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Células Tumorais Cultivadas
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