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1.
Lasers Surg Med ; 55(5): 480-489, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37003294

RESUMO

OBJECTIVES: Postoperative bile leakage is a common complication of hepatobiliary surgery and frequently requires procedural intervention. Bile-label 760 (BL-760), a novel near-infrared dye, has emerged as a promising tool for identifying biliary structures and leakage, owing to its rapid excretion and strong bile specificity. This study aimed to assess the intraoperative detection of biliary leakage using intravenously administered BL-760 compared with intravenous (IV) and intraductal (ID) indocyanine green (ICG). MATERIALS AND METHODS: Laparotomy and segmental hepatectomy with vascular control were performed on two 25-30 kg pigs. ID ICG, IV ICG, and IV BL-760 were administered separately, followed by an examination of the liver parenchyma, cut liver edge, and extrahepatic bile ducts for areas of leakage. The duration of intra- and extrahepatic fluorescence detection was assessed, and the target-to-background (TBR) of the bile ducts to the liver parenchyma was quantitatively measured. RESULTS: In Animal 1, after intraoperative BL-760 injection, three areas of leaking bile were identified within 5 min on the cut liver edge with a TBR of 2.5-3.8 that was not apparent to the naked eye. In contrast, after IV ICG administration, the background parenchymal signal and bleeding obscured the areas of bile leakage. A second dose of BL-760 demonstrated the utility of repeated injections, confirming two of the three previously visualized areas of bile leakage and revealing one previously unseen leak. In Animal 2, neither ID ICG nor IV BL-760 injections showed obvious areas of bile leakage. However, fluorescence signals were observed within the superficial intrahepatic bile ducts after both injections. CONCLUSIONS: BL-760 enables the rapid intraoperative visualization of small biliary structures and leaks, with the benefits of fast excretion, repeatable intravenous administration, and high-fluorescence TBR in the liver parenchyma. Potential applications include the identification of bile flow in the portal plate, biliary leak or duct injury, and postoperative monitoring of drain output. A thorough assessment of the intraoperative biliary anatomy could limit the need for postoperative drain placement, a possible contributor to severe complications and postoperative bile leak.


Assuntos
Bile , Corantes Fluorescentes , Suínos , Animais , Hepatectomia/efeitos adversos , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/cirurgia , Ductos Biliares/lesões , Verde de Indocianina
2.
Lasers Surg Med ; 53(10): 1427-1434, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34036583

RESUMO

BACKGROUND AND OBJECTIVES: Meticulous dissection and identification of nerves during head and neck surgery are crucial for preventing nerve damage. At present, nerve identification relies heavily on the surgeon's knowledge of anatomy, optionally combined with intraoperative neuromonitoring. Recently, optical techniques such as Mueller polarimetric imaging (MPI) have shown potential to improve nerve identification. STUDY DESIGN/MATERIALS AND METHODS: With institutional approval, seven 25-35 kg Yorkshire pigs underwent cervical incision in the central neck. Intraoperative images were obtained using our in-house MPI system. Birefringence maps from the MPI system were processed to quantify the values between 0 and 255 from different tissue types; an active contour model was applied to further improve nerve visualization on the corresponding color images. RESULTS: Among the seven pigs, the vagus nerves and recurrent laryngeal nerves were successfully differentiated with a mean intensity of 130.954 ± 20.611, which was significantly different (P < 0.05) from those of arteries (78.512 ± 27.78) and other surrounding tissues (82.583 ± 35.547). There were no imaging-related complications during the procedure. © 2021 Wiley Periodicals LLC. CONCLUSIONS: MPI is a potentially complementary intraoperative tool for nerve identification in adjacent tissues.


Assuntos
Nervo Laríngeo Recorrente , Tireoidectomia , Animais , Estudos de Viabilidade , Pescoço/diagnóstico por imagem , Pescoço/cirurgia , Suínos
3.
Pediatr Surg Int ; 37(1): 129-135, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33242170

RESUMO

PURPOSE: Adnexal torsion is a gynecologic emergency, requiring intervention for tissue preservation. At our institution, torsion is managed by pediatric surgeons or gynecologists. We evaluated differences between specialties to streamline evaluation for children with gynecological emergencies, develop a clinical pathway, and prevent care delays. METHODS: A retrospective review of adolescents undergoing intervention for adnexal torsion from 2004-2018 was performed. Differences in time to intervention, operation duration, the procedure performed, and length of stay (LOS) between the specialties were analyzed. RESULTS: Eighty-six patients underwent 94 operations for presumed adnexal torsion with 87 positive cases. Pediatric surgeons performed 60 operations and 34 cases were performed by gynecologists. Preservation of fertility was the goal in both cohorts and the rate of oophoropexy, cystectomy, and oophorectomy were similar between the cohorts (p = 0.14, p = 1.0, p = 0.39, respectively). There was no difference in intra-operative time (p = 0.69). LOS was shorter in the gynecology cohort (median 1 day [1-2] vs. 2 days [2-3], p > 0.001). CONCLUSIONS: Adnexal torsion is a time-sensitive diagnosis requiring prompt intervention for ovarian or fallopian tube preservation. A multidisciplinary institutional care pathway should be developed and implemented.


Assuntos
Ginecologia/estatística & dados numéricos , Torção Ovariana/cirurgia , Pediatras/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Adolescente , Criança , Estudos de Coortes , Emergências , Feminino , Humanos , Ovariectomia/estatística & dados numéricos , Estudos Retrospectivos
4.
Pediatr Surg Int ; 36(3): 407-414, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31773248

RESUMO

INTRODUCTION: The pediatric quality indicator (PDI) measures released by the Agency for Healthcare Research and Quality (AHRQ) provide an impetus for benchmarking quality of care in children. The PDI-17, aimed at studying perforation in appendicitis, is one such measure that this study aims to utilize to assess surgical care delivery and outcomes in children managed at majority-minority hospitals. METHODS: The Kid Inpatient Database (2000-2012) was queried for pediatric patients (< 18 years) with a diagnosis of appendicitis, with and without perforation. Facilities were categorized into tertiles based on rates of perforation (PDI-17). Similarly, tertiles were generated based on volume of minority patients (Black and Hispanic) treated at each facility. Multivariable regression analysis adjusted for demographic parameters, hospital-level characteristics, propensity score quintiles, clinically relevant outcomes, and tertiles of minority patients treated. RESULTS: Of the 322,805 patients with appendicitis 28.7% had perforated appendicitis. Patients presenting to facilities caring for a higher volume of perforated appendicitis were younger with public insurance or no insurance and, however, these patients were less likely to belong to a minority group (p < 0.05). Additionally, these patients were less likely to belong to the highest income quartile (OR [95% CI] 0.45 [0.39-0.52]). Hospitals treating the highest volume of minority patients [majority-minority hospitals (MMHs)] had an 87% (OR [95% CI] 1.87 [1.77-1.98]) increased likelihood of also treating the highest rates of perforated appendicitis. CONCLUSION: Hospitals treating a high volume of complicated appendicitis are less likely to care for minority groups. Additionally, MMHs lacking experience and volume in caring for complicated appendicitis have an increased likelihood of patients with perforations which is indicative of poor healthcare access.


Assuntos
Apendicectomia/métodos , Apendicite/cirurgia , Atenção à Saúde/métodos , Acessibilidade aos Serviços de Saúde/organização & administração , Hospitais com Alto Volume de Atendimentos/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Estados Unidos
5.
Pediatr Surg Int ; 35(6): 649-655, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30868210

RESUMO

PURPOSE: To review the effectiveness of the longitudinal intestinal lengthening and tailoring (LILT) and serial transverse enteroplasty (STEP) operations in a cohort of patients with short bowel syndrome (SBS). METHODS: We conducted a retrospective analysis of children with SBS treated at our institution from 2004 until 2014. Children aged 0 days to 18 years with SBS who underwent autologous intestinal reconstruction were included in the study. RESULTS: Twenty-two SBS patients underwent 31 different lengthening procedures (LP). Seventeen patients underwent their primary lengthening procedures at our institution: 9 (53%) patients underwent a LILT, 7 (41%) underwent a STEP and 1 (6%) had a simultaneous LILT and STEP procedure. 12/22 patients had a second STEP, two had a third STEP and one patient had an intestinal transplantation after the LP. Median intestinal length at the time of surgery was 25 cm (range 12-90 cm). There was no difference in gain of intestinal length after LILT vs. STEP (p = 0.74). Length of stay and initiation of feeds were similar. Serum albumin increased after autologous bowel lengthening (p < 0.001). 50% were weaned off parenteral nutrition (PN) (5/9 of the LILT, 1/7 of the STEP, 1/1 of the combined LILT/STEP). There were no surgical complications or deaths. CONCLUSION: In patients with SBS, LILT and STEP procedures are effective for autologous intestinal reconstruction and enable intestinal rehabilitation.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Intestinos/cirurgia , Síndrome do Intestino Curto/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Tempo de Internação , Masculino , Nutrição Parenteral , Estudos Retrospectivos , Albumina Sérica/análise
6.
PLoS Med ; 15(1): e1002497, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29377881

RESUMO

BACKGROUND: Adaptive immune resistance induces an immunosuppressive tumor environment that enables immune evasion. This phenomenon results in tumor escape with progression and metastasis. Programmed cell death-ligand 1 (PD-L1) expressed on tumors is thought to inhibit tumor-infiltrating lymphocytes (TILs) through programmed cell death 1 (PD1), enabling adaptive immune resistance. This study investigates the role of PD-L1 in both mouse and human neuroblastoma immunity. The consequence of PD-L1 inhibition is characterized in the context of an established whole tumor cell vaccine. METHODS AND FINDINGS: A mouse model of neuroblastoma was investigated using an Id2 knockdown whole cell vaccine in combination with checkpoint inhibition. We show that immunogenic mouse neuroblastoma acquires adaptive immune resistance by up-regulating PD-L1 expression, whereas PD-L1 is of lesser consequence in nonimmunogenic neuroblastoma tumors. Combining PD-L1 checkpoint inhibition with whole tumor cell/anti-CTLA-4 vaccination enhanced tumor cell killing, cured mice with established tumors, and induced long-term immune memory (6 months). From an evaluation of patient neuroblastoma tumors, we found that the inflammatory environment of the mouse neuroblastoma mimicked human disease in which PD-L1 expression was associated directly with TILs and lower-risk tumors. High-risk patient tumors were lacking both TILs and PD-L1 expression. Although a correlation in immunity seems to exist between the mouse model and human findings, the mouse tumor model is induced and not spontaneously occurring, and furthermore, the number of both mouse and human correlates is limited. CONCLUSIONS: This study demonstrates the role PD-L1 plays in neuroblastoma's resistance to immunity and defines the nonredundant effect of combination checkpoint inhibition with vaccine therapy in a mouse model. High-risk, nonimmunogenic human tumors display both diminished PD-L1 expression and adaptive immune resistance. Paradoxically, high-risk tumors may be more responsive to effective vaccine therapy because of their apparent lack of adaptive immune resistance.


Assuntos
Imunidade Adaptativa , Antígeno B7-H1/genética , Antígeno CTLA-4/imunologia , Vacinas Anticâncer/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neuroblastoma/imunologia , Animais , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Vacinação
7.
Am J Perinatol ; 35(11): 1079-1086, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29609189

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a complication of prematurity with a high mortality rate. Currently, there are no reliable biomarkers capable of identifying infants at risk for developing NEC. We sought to determine the autonomic nervous system antecedents of NEC in premature infants, using heart rate variability (HRV). MATERIALS AND METHODS: HRV was quantified by retrieving archived electrocardiogram (EKG) data from 30 premature infants from 4 days prior, through 4 days after, the clinical NEC diagnosis. HRV metrics were compared with those on the diagnosis day using the receiver operating characteristic (ROC) analysis. RESULTS: HRV metrics showed a depression of autonomic tone that preceded the clinical NEC diagnosis by 2 days, and which recovered to baseline by 2 days after diagnosis (area under the curve [AUC] < 0.7). The pattern of HRV change was significantly associated with the clinical severity of NEC (stage II vs. stage III). CONCLUSION: Our studies suggest that readily accessible metrics of autonomic depression might expedite the diagnosis of NEC and its severity in a clinically meaningful manner. Clearly, these studies need to be extended prospectively to determine the diagnostic utility of this approach.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Enterocolite Necrosante/diagnóstico , Doenças do Prematuro/diagnóstico , Biomarcadores , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Masculino , Curva ROC
8.
Nanomedicine ; 13(2): 771-781, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27826115

RESUMO

We describe "photothermal immunotherapy," which combines Prussian blue nanoparticle (PBNP)-based photothermal therapy (PTT) with anti-CTLA-4 checkpoint inhibition for treating neuroblastoma, a common, hard-to-treat pediatric cancer. PBNPs exhibit pH-dependent stability, which makes them suitable for intratumorally-administered PTT. PBNP-based PTT is able to lower tumor burden and prime an immune response, specifically an increased infiltration of lymphocytes and T cells to the tumor area, which is complemented by the antitumor effects of anti-CTLA-4 immunotherapy, providing a more durable treatment against neuroblastoma in an animal model. We observe 55.5% survival in photothermal immunotherapy-treated mice at 100days compared to 12.5%, 0%, 0%, and 0% survival in mice receiving: anti-CTLA-4 alone, PBNPs alone, PTT alone, and no treatment, respectively. Additionally, long-term surviving, photothermal immunotherapy-treated mice exhibit protection against neuroblastoma rechallenge, suggesting the development of immunity against these tumors. Our findings suggest the potential of photothermal immunotherapy in improving treatments for neuroblastoma.


Assuntos
Imunoterapia/métodos , Nanopartículas , Neuroblastoma/terapia , Fototerapia , Animais , Antígeno CTLA-4/imunologia , Corantes/química , Camundongos , Nanomedicina , Linfócitos T
9.
Inflamm Res ; 65(9): 737-43, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27261270

RESUMO

OBJECTIVE AND DESIGN: The goal of this study was to assess the capacity of VBP15, a dissociative steroidal compound, to reduce pro-inflammatory cytokine expression in vitro, to reduce symptoms of colitis in the trinitrobenzene sulfonic acid-induced murine model, and to assess the effect of VBP15 on growth stunting in juvenile mice. MATERIALS: In vitro studies were performed in primary human intestinal epithelial cells. Colitis was induced in mice by administering trinitrobenzene sulfonic acid. Growth stunting studies were performed in wild type outbred mice. TREATMENT: Cells were treated with VBP15 or prednisolone (10 µM) for 24 h. Mice were subjected to 3 days of VBP15 (30 mg/kg) or prednisolone (30 mg/kg) in the colitis study. In the growth stunting study, mice were subjected to VBP15 (10, 30, 45 mg/kg) or prednisolone (10 mg/kg) for 5 weeks. METHODS: Cytokines were measured by PCR and via Luminex. Colitis symptoms were evaluated by assessing weight loss, intestinal blood, and stool consistency. Growth stunting was assessed using an electronic caliper. RESULTS: VBP15 significantly reduced the in vitro production of CCL5 (p < 0.001) IL-6 (p < 0.001), IL-8 (p < 0.05) and reduced colitis symptoms (p < 0.05). VBP15 caused less growth stunting than prednisolone (p < 0.001) in juvenile mice. CONCLUSION: VBP15 may reduce symptoms of IBD, while decreasing or avoiding detrimental side effects.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Pregnadienodiois/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Tamanho Corporal/efeitos dos fármacos , Células Cultivadas , Colite/induzido quimicamente , Colite/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Pregnadienodiois/farmacologia , Ácido Trinitrobenzenossulfônico
11.
PLoS Genet ; 7(10): e1002325, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22022284

RESUMO

We report an early onset spastic ataxia-neuropathy syndrome in two brothers of a consanguineous family characterized clinically by lower extremity spasticity, peripheral neuropathy, ptosis, oculomotor apraxia, dystonia, cerebellar atrophy, and progressive myoclonic epilepsy. Whole-exome sequencing identified a homozygous missense mutation (c.1847G>A; p.Y616C) in AFG3L2, encoding a subunit of an m-AAA protease. m-AAA proteases reside in the mitochondrial inner membrane and are responsible for removal of damaged or misfolded proteins and proteolytic activation of essential mitochondrial proteins. AFG3L2 forms either a homo-oligomeric isoenzyme or a hetero-oligomeric complex with paraplegin, a homologous protein mutated in hereditary spastic paraplegia type 7 (SPG7). Heterozygous loss-of-function mutations in AFG3L2 cause autosomal-dominant spinocerebellar ataxia type 28 (SCA28), a disorder whose phenotype is strikingly different from that of our patients. As defined in yeast complementation assays, the AFG3L2(Y616C) gene product is a hypomorphic variant that exhibited oligomerization defects in yeast as well as in patient fibroblasts. Specifically, the formation of AFG3L2(Y616C) complexes was impaired, both with itself and to a greater extent with paraplegin. This produced an early-onset clinical syndrome that combines the severe phenotypes of SPG7 and SCA28, in additional to other "mitochondrial" features such as oculomotor apraxia, extrapyramidal dysfunction, and myoclonic epilepsy. These findings expand the phenotype associated with AFG3L2 mutations and suggest that AFG3L2-related disease should be considered in the differential diagnosis of spastic ataxias.


Assuntos
Proteases Dependentes de ATP/genética , Encéfalo/anormalidades , Metaloendopeptidases/genética , Mitocôndrias/enzimologia , Paraplegia Espástica Hereditária/genética , Degenerações Espinocerebelares/genética , ATPases Associadas a Diversas Atividades Celulares , Adolescente , Sequência de Aminoácidos , Animais , Encéfalo/patologia , Criança , Diagnóstico Diferencial , Exoma/genética , Genótipo , Células HeLa , Homozigoto , Humanos , Masculino , Metaloendopeptidases/metabolismo , Camundongos , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Paraplegia , Dobramento de Proteína , Irmãos , Paraplegia Espástica Hereditária/patologia , Ataxias Espinocerebelares/congênito , Degenerações Espinocerebelares/patologia , Leveduras/genética
12.
N Engl J Med ; 363(14): 1313-23, 2010 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-20879880

RESUMO

BACKGROUND: The survival rate among patients with intermediate-risk neuroblastoma who receive dose-intensive chemotherapy is excellent, but the survival rate among patients who receive reduced doses of chemotherapy for shorter periods of time is not known. METHODS: We conducted a prospective, phase 3, nonrandomized trial to determine whether a 3-year estimated overall survival of more than 90% could be maintained with reductions in the duration of therapy and drug doses, using a tumor biology-based therapy assignment. Eligible patients had newly diagnosed, intermediate-risk neuroblastoma without MYCN amplification; these patients included infants (<365 days of age) who had stage 3 or 4 disease, children (≥365 days of age) who had stage 3 tumors with favorable histopathological features, and infants who had stage 4S disease with a diploid DNA index or unfavorable histopathological features. Patients who had disease with favorable histopathological features and hyperdiploidy were assigned to four cycles of chemotherapy, and those with an incomplete response or either unfavorable feature were assigned to eight cycles. RESULTS: Between 1997 and 2005, a total of 479 eligible patients were enrolled in this trial (270 patients with stage 3 disease, 178 with stage 4 disease, and 31 with stage 4S disease). A total of 323 patients had tumors with favorable biologic features, and 141 had tumors with unfavorable biologic features. Ploidy, but not histopathological features, was significantly predictive of the outcome. Severe adverse events without disease progression occurred in 10 patients (2.1%), including secondary leukemia (in 3 patients), death from infection (in 3 patients), and death at surgery (in 4 patients). The 3-year estimate (±SE) of overall survival for the entire group was 96±1%, with an overall survival rate of 98±1% among patients who had tumors with favorable biologic features and 93±2% among patients who had tumors with unfavorable biologic features. CONCLUSIONS: A very high rate of survival among patients with intermediate-risk neuroblastoma was achieved with a biologically based treatment assignment involving a substantially reduced duration of chemotherapy and reduced doses of chemotherapeutic agents as compared with the regimens used in earlier trials. These data provide support for further reduction in chemotherapy with more refined risk stratification. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00003093.)


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neuroblastoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Humanos , Lactente , Análise de Intenção de Tratamento , Estadiamento de Neoplasias , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-37044114

RESUMO

Materials employed in the treatment of conditions encountered in surgical and clinical practice frequently face barriers in translation to application. Shortcomings can be generalized through their reduced mechanical stability, difficulty in handling, and inability to conform or adhere to complex tissue surfaces. To overcome an amalgam of challenges, research has sought the utilization of polymer-derived nanomaterials deposited in various fashions and formulations to improve the application and outcomes of surgical and clinical interventions. Clinically prevalent applications include topical wound dressings, tissue adhesives, surgical sealants, hemostats, and adhesion barriers, all of which have displayed the potential to act as superior alternatives to current materials used in surgical procedures. In this review, emphasis will be placed not only on applications, but also on various design strategies employed in fabrication. This review is designed to provide a broad and thought-provoking understanding of nanomaterials as adjuvant tools for the assisted treatment of pathologies prevalent in surgery. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery.


Assuntos
Adesivo Tecidual de Fibrina , Adesivos Teciduais , Adesivo Tecidual de Fibrina/uso terapêutico , Polímeros , Adesivos Teciduais/uso terapêutico , Adjuvantes Imunológicos
14.
Bioeng Transl Med ; 8(1): e10335, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684071

RESUMO

Adhesions are dense, fibrous bridges that adjoin tissue surfaces due to uncontrolled inflammation following postoperative mesothelial injury. A widely used adhesion barrier material in Seprafilm often fails to prevent transverse scar tissue deposition because of its poor mechanical properties, rapid degradation profile, and difficulty in precise application. Solution blow spinning (SBS), a polymer fiber deposition technique, allows for the placement of in situ tissue-conforming and tissue-adherent scaffolds with exceptional mechanical properties. While biodegradable polymers such as poly(lactic-co-glycolic acid) (PLGA) have desirable strength, they exhibit bulk biodegradation rates and inflammatory profiles that limit their use as adhesion barriers and result in poor tissue adhesion. Here, viscoelastic poly(lactide-co-caprolactone) (PLCL) is used for its pertinent biodegradation mechanism. Because it degrades via surface erosion, spray deposited PLCL fibers can dissolve new connections formed by inflamed tissue, allowing them to function as an effective, durable, and easy-to-apply adhesion barrier. Degradation kinetics are tuned to match adhesion formation through the design of PLCL blends comprised of highly adhesive "low"-molecular weight (LMW) constituents in a mechanically robust "high"-molecular weight (HMW) matrix. In vitro studies demonstrate that blending LMW PLCL (30% w/v) with HMW PLCL (70% w/v) yields an anti-fibrotic yet tissue-adhesive polymer sealant with a 14-day erosion rate countering adhesion formation. PLCL blends additionally exhibit improved wet tissue adhesion strength (~10 kPa) over a 14-day period versus previously explored biodegradable polymer compositions, such as PLGA. In a mouse cecal ligation model, select PLCL blends significantly reduce abdominal adhesions severity versus no treatment and Seprafilm-treated controls.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36884271

RESUMO

Formation of asymmetric, rigid scar tissue known as surgical adhesions is caused by traumatic disruption of mesothelial-lined surfaces in surgery. A widely adopted prophylactic barrier material (Seprafilm) for the treatment of intra-abdominal adhesions is applied operatively as a pre-dried hydrogel sheet but has reduced translational efficacy due its brittle mechanical properties. Topically administered peritoneal dialysate (Icodextrin) and anti-inflammatory drugs have failed to prevent adhesions due to an uncontrolled release profile. Hence, inclusion of a targeted therapeutic into a solid barrier host matrix with improved mechanical properties could provide dual utility in adhesion prevention and as a surgical sealant. Spray deposition of poly(lactide-co-caprolactone) (PLCL) polymer fibers through solution blow spinning has yielded a tissue-adherent barrier material with previously reported adhesion prevention efficacy due to a surface erosion mechanism that inhibits deposition of inflamed tissue. However, such an approach uniquely presents an avenue for controlled therapeutic release through mechanisms of diffusion and degradation. Such a rate is kinetically tuned via facile blending of "high" molecular weight (HMW) and "low" molecular weight (LMW) PLCL with slow and fast biodegradation rates, respectively. Here, we explore viscoelastic blends of HMW PLCL (70% w/v) and LMW PLCL (30% w/v) as a host matrix for anti-inflammatory drug delivery. In this work, COG133, an apolipoprotein E (ApoE) mimetic peptide with potent anti-inflammatory properties was selected and tested. In vitro studies with PLCL blends presented low (∼30%) and high (∼80%) percent release profiles over a 14-day period based on the nominal molecular weight of the HMW PLCL component. Two independent mouse models of cecal ligation and cecal anastomosis significantly reduced adhesion severity versus Seprafilm, COG133 liquid suspension, and no treatment control. The synergy of physical and chemical methods in a barrier material with proven preclinical studies highlights the value of COG133-loaded PLCL fiber mats in effectively dampening the formation of severe abdominal adhesions.

16.
Eur J Pediatr Surg ; 33(6): 463-468, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36356590

RESUMO

BACKGROUND: The posterior sagittal anorectoplasty (PSARP) used to repair an anorectal malformation (ARM) with a rectovestibular fistula involves incising the perineal body skin and the sphincter muscles and a posterior sagittal incision to the coccyx. Perineal body dehiscence is the most common and morbid complication post-PSARP which can have a negative impact on future bowel control. With consideration of all the other approaches described to repair this anomaly, we developed a perineal body sparing modification of the standard PSARP technique. METHODS: Four patients with ARM with a rectovestibular fistula were repaired with a perineal body sparing modified PSARP at a single institution between 2020 and 2021. The incision used was limited, involving only the length of the anal sphincter, with no incision anterior or posterior to the planned anoplasty. Dissection of the distal rectum and fistula was performed without cutting the perineal body. Once the distal rectum was mobilized off the posterior vaginal wall and out of the vestibule, the perineal body muscles, where the fistula had been, were reinforced and an anoplasty was then performed. RESULTS: Operative time was the same as for a standard PSARP. There were no intraoperative or postoperative complications. No postoperative dilations were performed. All patients healed well with an excellent cosmetic result. All are too young to assess for bowel control. CONCLUSION: We present a new technique, a modification of the traditional PSARP for rectovestibular fistula, which spares the perineal body. This approach could eliminate the potential complication of perineal body dehiscence.


Assuntos
Malformações Anorretais , Fístula Retal , Feminino , Humanos , Lactente , Reto/cirurgia , Malformações Anorretais/cirurgia , Estudos Retrospectivos , Fístula Retal/cirurgia , Canal Anal/cirurgia , Resultado do Tratamento
17.
Front Immunol ; 14: 1176370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346042

RESUMO

Introduction: The combination of Myc-suppressed whole tumor cells with checkpoint inhibitors targeting CTLA-4 and PD-L1 generates a potent therapeutic cancer vaccine in a mouse neuroblastoma model. As immunotherapies translate from pre-clinical to clinical trials, the potential immune-related adverse events (irAEs) associated with induction of potent immunity must be addressed. The CD24-Siglec 10/G interaction is an innate checkpoint that abrogates inflammatory responses to molecules released by damaged cells, but its role in cancer immunology is not well defined. We investigate irAEs of an effective whole cell neuroblastoma vaccine and subsequently the effect of CD24-Fc, a CD24 and Fc fusion protein, on both the vaccine efficacy and induced irAEs in a mouse neuroblastoma model. Methods: To test whether the whole tumor cell vaccination leads to autoimmune responses in other organ systems we harvested lung, heart, kidney and colon from naïve mice (n=3), unvaccinated tumor only mice (n=3), and vaccinated mice with CD24 Fc (n=12) or human IgG-Fc control (n=12) after tumor inoculation and vaccination therapy at day 30. The Immune cell infiltrates and immunogenic pathway signatures in different organ systems were investigated using NanoString Autoimmune Profiling arrays. Nanostring RNA transcript results were validated with immunohistochemistry staining. Results: The whole tumor cell vaccine combined with immune checkpoint therapy triggers occult organ specific immune cell infiltrates, primarily in cardiac tissue and to a lesser extent in the renal and lung tissue, but not in the colon. CD24-Fc administration with vaccination partially impedes anti-tumor immunity but delaying CD24-Fc administration after initial vaccination reverses this effect. CD24-Fc treatment also ameliorates the autoimmune response induced by effective tumor vaccination in the heart. Discussion: This study illustrates that the combination of Myc suppressed whole tumor cell vaccination with checkpoint inhibitors is an effective therapy, but occult immune infiltrates are induced in several organ systems in a mouse neuroblastoma model. The systemic administration of CD24-Fc suppresses autoimmune tissue responses, but appropriate timing of administration is critical for maintaining efficacy of the therapeutic vaccine.


Assuntos
Vacinas Anticâncer , Neuroblastoma , Camundongos , Humanos , Animais , Neuroblastoma/metabolismo , Vacinação , Imunoterapia/métodos , Imunoterapia Ativa , Antígeno CD24
18.
Am J Surg ; 223(4): 774-779, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34325911

RESUMO

INTRODUCTION: Non-accidental trauma (NAT) is one of the common causes of injury in children in the United States (US). Abuse and maltreatment affect 2 per 100,000 children annually and may go unrecognized. The aim of this study to quantify the recidivistic nature of NAT in the US pediatric population. METHODS: The National Readmissions Database (2007-2015) was queried for pediatric (≤18y) trauma patients. Children presenting for non-accidental trauma were further identified. Data was obtained on demographic, clinical, and hospital-level characteristics. Body regions with an Abbreviated Injury Scale (AIS) greater than three were further identified. Multivariable logistic regression analysis (adjusting for age, gender, insurance status, year, Injury Severity Score [ISS], hospital region, and mechanism of injury) was utilized to determine factors influencing unintentional and intentional (assault) non-accidental traumatic injuries. RESULTS: NAT represents 1.6% (n = 4,634/286,508) of all pediatric trauma. The median age of presentation was <1y [IQR:0-3] with a male predominance (56.2%). Median ISS was 9 [IQR:2-16]. 87.5% of incidents represented assault (intentional). The most commonly affected body region was the head and neck (32.8%), followed by the extremities (11.4%) and soft tissue trauma or burns (6.3%). Penetrating trauma accounted for 18% of these injuries. 3.2% were readmitted to the hospital for a recurrent episode. 85.5% presented to the hospital for their initial evaluation. Mortality rates were 3.8% for those re-admitted to the hospital. The most common perpetrators were other specified persons known to the family, followed by fathers and mothers. CONCLUSION: Although uncommon, recidivism, after an initial episode of NAT, can have devastating consequences. The majority of the perpetrators of abuse are individuals known to the patient or family. Health policy aimed towards developing preventative strategies is needed to facilitate early recognition and tackle abuse in children. LEVEL OF EVIDENCE: III. TYPE OF EVIDENCE: Case Control Study.


Assuntos
Maus-Tratos Infantis , Reincidência , Ferimentos e Lesões , Estudos de Casos e Controles , Criança , Feminino , Humanos , Escala de Gravidade do Ferimento , Pacientes Internados , Masculino , Estudos Retrospectivos , Centros de Traumatologia , Estados Unidos/epidemiologia , Ferimentos e Lesões/epidemiologia
19.
Front Immunol ; 13: 991790, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341364

RESUMO

Immunotherapy is a key modality in the treatment of cancer, but many tumors remain immune resistant. The classic mouse model of B16-F10 melanoma is immune resistant even in the face of checkpoint inhibition. Apolipoprotein E (apoE), a known immune suppressant is strikingly elevated in many human tumors, but its role in cancer immunology is not defined. We investigated the role of apoE in the immune micro-environment using a mouse melanoma model. We demonstrate that ApoE is -highly expressed in wild-type B16-F10 melanoma and serum levels progressively increase as tumors grow. The conditioned media from wild type ApoE secreting melanoma cells suppress T-cell activation in vitro while this suppressive effect is absent in conditioned media from ApoE knock out tumor cells. Mechanistically, apoE induces IL-10 secreting dendritic cells and stimulates T-cell apoptosis and arrest partially via the lrp8 receptor. Ablating ApoE in mice inoculated with tumor cells enabled tumor cell rejection and was associated with induction of immune pathway activation and immune cell infiltration. Tumor secreted apoE appears to be a potent immune cell checkpoint and targeting apoE is associated with enhanced tumor immunity in the mouse melanoma model.


Assuntos
Melanoma Experimental , Animais , Camundongos , Humanos , Meios de Cultivo Condicionados , Camundongos Endogâmicos C57BL , Apolipoproteínas E , Apolipoproteínas , Microambiente Tumoral
20.
J Med Imaging (Bellingham) ; 9(6): 064502, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36466077

RESUMO

Purpose: Intraoperative evaluation of bowel perfusion is currently dependent upon subjective assessment. Thus, quantitative and objective methods of bowel viability in intestinal anastomosis are scarce. To address this clinical need, a conditional adversarial network is used to analyze the data from laser speckle contrast imaging (LSCI) paired with a visible-light camera to identify abnormal tissue perfusion regions. Approach: Our vision platform was based on a dual-modality bench-top imaging system with red-green-blue (RGB) and dye-free LSCI channels. Swine model studies were conducted to collect data on bowel mesenteric vascular structures with normal/abnormal microvascular perfusion to construct the control or experimental group. Subsequently, a deep-learning model based on a conditional generative adversarial network (cGAN) was utilized to perform dual-modality image alignment and learn the distribution of normal datasets for training. Thereafter, abnormal datasets were fed into the predictive model for testing. Ischemic bowel regions could be detected by monitoring the erroneous reconstruction from the latent space. The main advantage is that it is unsupervised and does not require subjective manual annotations. Compared with the conventional qualitative LSCI technique, it provides well-defined segmentation results for different levels of ischemia. Results: We demonstrated that our model could accurately segment the ischemic intestine images, with a Dice coefficient and accuracy of 90.77% and 93.06%, respectively, in 2560 RGB/LSCI image pairs. The ground truth was labeled by multiple and independent estimations, combining the surgeons' annotations with fastest gradient descent in suspicious areas of vascular images. The total processing time was 0.05 s for an image size of 256 × 256 . Conclusions: The proposed cGAN can provide pixel-wise and dye-free quantitative analysis of intestinal perfusion, which is an ideal supplement to the traditional LSCI technique. It has potential to help surgeons increase the accuracy of intraoperative diagnosis and improve clinical outcomes of mesenteric ischemia and other gastrointestinal surgeries.

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