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1.
Biochemistry ; 63(13): 1599-1607, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38907702

RESUMEN

Small-scale bioreactors that are affordable and accessible would be of major benefit to the research community. In previous work, an open-source, automated bioreactor system was designed to operate up to the 30 mL scale with online optical monitoring, stirring, and temperature control, and this system, dubbed Chi.Bio, is now commercially available at a cost that is typically 1-2 orders of magnitude less than commercial bioreactors. In this work, we further expand the capabilities of the Chi.Bio system by enabling continuous pH monitoring and control through hardware and software modifications. For hardware modifications, we sourced low-cost, commercial pH circuits and made straightforward modifications to the Chi.Bio head plate to enable continuous pH monitoring. For software integration, we introduced closed-loop feedback control of the pH measured inside the Chi.Bio reactors and integrated a pH-control module into the existing Chi.Bio user interface. We demonstrated the utility of pH control through the small-scale depolymerization of the synthetic polyester, poly(ethylene terephthalate) (PET), using a benchmark cutinase enzyme, and compared this to 250 mL bioreactor hydrolysis reactions. The results in terms of PET conversion and rate, measured both by base addition and product release profiles, are statistically equivalent, with the Chi.Bio system allowing for a 20-fold reduction of purified enzyme required relative to the 250 mL bioreactor setup. Through inexpensive modifications, the ability to conduct pH control in Chi.Bio reactors widens the potential slate of biochemical reactions and biological cultivations for study in this system, and may also be adapted for use in other bioreactor platforms.


Asunto(s)
Reactores Biológicos , Tereftalatos Polietilenos , Tereftalatos Polietilenos/química , Tereftalatos Polietilenos/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/química , Burkholderiales/enzimología , Burkholderiales/metabolismo , Programas Informáticos
2.
BMC Genomics ; 25(1): 417, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678201

RESUMEN

BACKGROUND: Between 2020 and 2022, eight calves in a Nebraska herd (composite Simmental, Red Angus, Gelbvieh) displayed exercise intolerance during forced activity. In some cases, the calves collapsed and did not recover. Available sire pedigrees contained a paternal ancestor within 2-4 generations in all affected calves. Pedigrees of the calves' dams were unavailable, however, the cows were ranch-raised and retained from prior breeding seasons, where bulls used for breeding occasionally had a common ancestor. Therefore, it was hypothesized that a de novo autosomal recessive variant was causative of exercise intolerance in these calves. RESULTS: A genome-wide association analysis utilizing SNP data from 6 affected calves and 715 herd mates, followed by whole-genome sequencing of 2 affected calves led to the identification of a variant in the gene PYGM (BTA29:g.42989581G > A). The variant, confirmed to be present in the skeletal muscle transcriptome, was predicted to produce a premature stop codon (p.Arg650*). The protein product of PYGM, myophosphorylase, breaks down glycogen in skeletal muscle. Glycogen concentrations were fluorometrically assayed as glucose residues demonstrating significantly elevated glycogen concentrations in affected calves compared to cattle carrying the variant and to wild-type controls. The absence of the PYGM protein product in skeletal muscle was confirmed by immunohistochemistry and label-free quantitative proteomics analysis; muscle degeneration was confirmed in biopsy and necropsy samples. Elevated skeletal muscle glycogen persisted after harvest, resulting in a high pH and dark-cutting beef, which is negatively perceived by consumers and results in an economic loss to the industry. Carriers of the variant did not exhibit differences in meat quality or any measures of animal well-being. CONCLUSIONS: Myophosphorylase deficiency poses welfare concerns for affected animals and negatively impacts the final product. The association of the recessive genotype with dark-cutting beef further demonstrates the importance of genetics to not only animal health but to the quality of their product. Although cattle heterozygous for the variant may not immediately affect the beef industry, identifying carriers will enable selection and breeding strategies to prevent the production of affected calves.


Asunto(s)
Estudio de Asociación del Genoma Completo , Glucógeno Fosforilasa de Forma Muscular , Animales , Bovinos , Femenino , Masculino , Enfermedades de los Bovinos/genética , Genes Recesivos , Glucógeno Fosforilasa de Forma Muscular/genética , Glucógeno Fosforilasa de Forma Muscular/deficiencia , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Linaje , Polimorfismo de Nucleótido Simple , Secuenciación Completa del Genoma
3.
J Surg Res ; 282: 183-190, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36308901

RESUMEN

INTRODUCTION: Traumatic brain injury (TBI) can lead to neurocognitive decline, in part due to phosphorylated tau (p-tau). Whether p-tau accumulation worsens in the setting of polytrauma remains unknown. Propranolol has shown clinical benefit in head injuries; however, the underlying mechanism is also unknown. We hypothesize that hemorrhagic shock would worsen p-tau accumulation but that propranolol would improve functional outcomes on behavioral studies. METHODS: A murine polytrauma model was developed to examine the accumulation of p-tau and whether it can be mitigated by early administration of propranolol. TBI was induced using a weight-drop model and hemorrhagic shock was achieved via controlled hemorrhage for 1 h. Mice were given intraperitoneal propranolol 4 mg/kg or saline control. The animals underwent behavioral testing at 30 d postinjury and were sacrificed for cerebral histological analysis. These studies were completed in male and female mice. RESULTS: TBI alone led to increased p-tau generation compared to sham on both immunohistochemistry and immunofluorescence (P < 0.05). The addition of hemorrhage led to greater accumulation of p-tau in the hippocampus (P < 0.007). In male mice, p-tau accumulation decreased with propranolol administration for both polytrauma and TBI alone (P < 0.0001). Male mice treated with propranolol also outperformed saline-control mice on the hippocampal-dependent behavioral assessment (P = 0.0013). These results were not replicated in female mice; the addition of hemorrhage did not increase p-tau accumulation and propranolol did not demonstrate a therapeutic effect. CONCLUSIONS: Polytrauma including TBI generates high levels of hippocampal p-tau, but propranolol may help prevent this accumulation to improve both neuropathological and functional outcomes in males.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Traumatismo Múltiple , Choque Hemorrágico , Animales , Ratones , Masculino , Femenino , Propranolol/farmacología , Propranolol/uso terapéutico , Choque Hemorrágico/complicaciones , Choque Hemorrágico/tratamiento farmacológico , Modelos Animales de Enfermedad
4.
Epilepsy Behav ; 144: 109260, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37244221

RESUMEN

PURPOSE: Certain anti-seizure medications (ASMs) adversely impact lipid values. Here, we explored the impact of ASMs on lipid values in adults with epilepsy. METHODS: A total of 228 adults with epilepsy were divided into four groups based on ASMs used: strong EIASMs, weak EIASMs, non-EIASMs, and no ASMs. Demographic information, epilepsy-specific clinical history, and lipid values were obtained through chart review. RESULTS: While there was no significant difference in lipid values between groups, there was a significant difference in the proportion of participants with dyslipidemia. Specifically, more participants exhibited elevated low-density lipoprotein (LDL) level in the strong EIASM group compared to the non-EIASM group (46.7% vs 18%, p < 0.05). In addition, more participants showed elevated LDL level in the weak EIASM group compared to the non-EIASM group (38% vs 18%, p < 0.05). Users of strong EIASMs showed greater odds of high LDL level (OR 5.734, p = 0.005) and high total cholesterol level (OR 4.913, p = 0.008) compared to users of non-EIASMs. When we analyzed the impact of individual ASMs used by more than 15% of the cohort on lipid levels, participants using valproic acid (VPA) showed lower high-density lipoprotein (p = 0.002) and higher triglyceride levels (p = 0.002) compared to participants not using VPA. CONCLUSION: Our study demonstrated a difference in the proportion of participants with dyslipidemia between ASM groups. Thus, adults with epilepsy using EIASMs should have careful monitoring of lipid values to address the risk of cardiovascular disease.


Asunto(s)
Epilepsia , Hipercolesterolemia , Humanos , Adulto , Epilepsia/tratamiento farmacológico , Ácido Valproico/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico
5.
Epilepsy Behav ; 144: 109279, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37271018

RESUMEN

BACKGROUND: The ketogenic diet (KD) is a high-fat, low-carbohydrate diet with therapeutic potential in refractory seizures, both in outpatient and inpatient settings. Successful implementation of KD involves a multifaceted, interdisciplinary approach to address anticipated challenges. We sought to characterize the utilization of KD among healthcare providers caring for adults with status epilepticus (SE). METHODS: We distributed a web-based survey through professional societies, including the American Academy of Neurology (AAN), Neurocritical Care Society (NCS), American Epilepsy Society (AES), Neuro Anesthesia and Critical Care Society (NACCS), and the Academy of Nutrition and Dietetics (AND), and via research contacts. We asked respondents about practice experience and experience using KD as a treatment for SE. Descriptive statistics and Chi-square tests were used to analyze the results. RESULTS: Of 156 respondents, 80% of physicians and 18% of non-physicians reported experience with KD for SE. Anticipated difficulty in achieving ketosis (36.3%), lack of expertise (24.2%), and lack of resources (20.9%) were identified as the most important barriers limiting the utilization of KD. The absence of dietitians (37.1%) or pharmacists (25.7%) support was the most important missing resource. Reasons for stopping KD included perceived ineffectiveness (29.1%), difficulty achieving ketosis (24.6%), and side effects (17.3%). Academic centers had more experience with the use of KD and greater EEG monitoring availability and fewer barriers to its implementation. The need for randomized clinical trials supporting efficacy (36.5%) and better practice guidelines for implementation and maintenance of KD (29.6%) were cited most frequently as factors to increase utilization of KD. CONCLUSION: This study identifies important barriers to the utilization of KD as a treatment for SE despite evidence supporting its efficacy in the appropriate clinical context, namely lack of resources and interdisciplinary support, and lack of established practice guidelines. Our results highlight the need for future research to improve understanding of the efficacy and safety of KD along with better interdisciplinary collaborations to increase its utilization.


Asunto(s)
Dieta Cetogénica , Epilepsia , Cetosis , Estado Epiléptico , Humanos , Adulto , Dieta Cetogénica/métodos , Estado Epiléptico/tratamiento farmacológico , Dieta Baja en Carbohidratos/métodos , Resultado del Tratamiento
6.
Molecules ; 28(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36677952

RESUMEN

Tetraazamacrocycles, cyclic molecules with four nitrogen atoms, have long been known to produce highly stable transition metal complexes. Cross-bridging such molecules with two-carbon chains has been shown to enhance the stability of these complexes even further. This provides enough stability to use the resulting compounds in applications as diverse and demanding as aqueous, green oxidation catalysis all the way to drug molecules injected into humans. Although the stability of these compounds is believed to result from the increased rigidity and topological complexity imparted by the cross-bridge, there is insufficient experimental data to exclude other causes. In this study, standard organic and inorganic synthetic methods were used to produce unbridged dibenzyl tetraazamacrocycle complexes of Co, Ni, Cu, and Zn that are analogues of known cross-bridged tetraazamacrocycles and their transition metal complexes to allow direct comparison of molecules that are identical except for the cross-bridge. The syntheses of the known tetraazamacrocycles and the new transition metal complexes were successful with high yields and purity. Initial chemical characterization of the complexes was conducted by UV-Visible spectroscopy, while cyclic voltammetry showed more marked differences in electronic properties from bridged versions. Direct comparison studies of the unbridged and bridged compounds' kinetic stabilities, as demonstrated by decomposition using high acid concentration and elevated temperature, showed that the cyclen-based complex stability did not benefit from cross-bridging. This is likely due to poor complementarity with the Cu2+ ion while cyclam-based complexes benefited greatly. We conclude that ligand-metal complementarity must be maintained in order for the topological and rigidity constraints imparted by the cross-bridge to contribute significantly to complex robustness.


Asunto(s)
Complejos de Coordinación , Ciclamas , Elementos de Transición , Humanos , Complejos de Coordinación/química , Estructura Molecular , Rayos X , Elementos de Transición/química , Etilenos/química , Cristalografía por Rayos X
7.
Syst Parasitol ; 100(6): 745-750, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37874423

RESUMEN

Ixodes (Afrixodes) ambohitantelensis n. sp. (Acari: Ixodidae) is described based on females ex endemic shrew tenrecs (Afrosoricida: Tenrecidae) and an introduced rodent (Rodentia: Muridae) from Madagascar. Females of this new species are similar to those of other species of the subgenus Afrixodes Morel, 1966, known from Madagascar, from which they can be distinguished by the size of scutum, size of scutal setae, shape of alloscutal setae, development of genital apron, size of auriculae, size of anterior angle of basis capituli, size of palpi, dental formula on hypostome, development of syncoxae, and size and development of spurs on coxae I and IV.


Asunto(s)
Ixodes , Ixodidae , Parásitos , Femenino , Animales , Tenrecidae , Roedores/parasitología , Musarañas , Muridae , Afrotheria , Madagascar , Especificidad de la Especie
8.
Nutr Neurosci ; 25(7): 1548-1557, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33487129

RESUMEN

BACKGROUND/AIMS: Ketogenic diet therapies (KDTs) offer a needed therapeutic option for patients with drug-resistant epilepsy. The current study investigated biochemical and anthropometric indices of cardiovascular disease (CVD) risk in adults with epilepsy treated with KDT over 6 months. METHOD: 65 adults with epilepsy naïve to diet therapy were enrolled in a prospective longitudinal study and instructed on modified Atkins diet (MAD) use. Seizure frequency, anthropometric measures, blood levels of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoproteins A1 and B, and lipoprotein sub-fractions were assessed at baseline, 3 months, and 6 months. RESULTS: Subsequent to study enrollment, 34 participants were lost to follow-up, elected not to start, or stopped MAD prior to study completion, leaving a total of 31 participants in the study at 6 months. Compared to baseline, participants on MAD showed significant reductions in median seizure frequency/week, weight, body mass index, waist and hip circumference, and percent body fat at 3 and 6 months. Compared to baseline, participants on MAD for 3 months showed significantly increased levels of total, small and medium LDL particles, ApoB and ApoB/A1 ratio. At 6 months, only small LDL particles and ApoB levels remained elevated and levels of ApoA1 had risen, suggesting possible compensatory adaptation over time. CONCLUSIONS: This study provides evidence demonstrating the efficacy and cardiovascular safety of 6 months of MAD use by adults with epilepsy. It also highlights an index of CVD risk - small LDL particles - that should be closely monitored.Trial registration: ClinicalTrials.gov identifier: NCT02694094..


Asunto(s)
Enfermedades Cardiovasculares , Dieta Rica en Proteínas y Pobre en Hidratos de Carbono , Dieta Cetogénica , Epilepsia , Adulto , Apolipoproteínas B , Enfermedades Cardiovasculares/prevención & control , Colesterol , Dieta Baja en Carbohidratos , Dieta Rica en Proteínas y Pobre en Hidratos de Carbono/efectos adversos , Dieta Cetogénica/efectos adversos , Humanos , Estudios Longitudinales , Estudios Prospectivos , Convulsiones , Resultado del Tratamiento
9.
Biochem Biophys Res Commun ; 562: 154-161, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34058562

RESUMEN

Overexpression of Axl, a TAM-family receptor tyrosine kinase, plays key roles in the formation, growth, and spread of tumors as well as resistance to targeted therapies and chemotherapies. We identified novel llama VHHs against human Axl using multiple complementary phage display selection strategies and characterized a subset of high-affinity VHHs. The VHHs targeted multiple sites in Ig-like domains 1 and 2 of the Axl extracellular domain, including an immunodominant epitope overlapping the site of Gas6 interaction and two additional non-Gas6 competitive epitopes recognized by murine monoclonal antibodies. Only a subset of VHHs cross-reacted with cynomolgus monkey Axl and none recognized mouse Axl. As fusions to human IgG1 Fc, VHH-Fcs bound Axl+ tumor cell lines and mertansine-loaded VHH-Fcs were cytotoxic in vitro against Axl+ cells in proportion to their binding affinities. Engineered biparatopic VHH-VHH heterodimers bound Axl avidly, and a subset of molecules showed dramatically enhanced association rates indicative of intramolecular binding. These VHHs may have applications as modular elements of biologic drugs such as antibody-drug conjugates.


Asunto(s)
Afinidad de Anticuerpos/inmunología , Proteínas Tirosina Quinasas Receptoras/inmunología , Anticuerpos de Dominio Único/inmunología , Animales , Células CHO , Camélidos del Nuevo Mundo , Muerte Celular , Línea Celular Tumoral , Cricetulus , Células HEK293 , Humanos , Cadenas Pesadas de Inmunoglobulina/inmunología , Cinética , Unión Proteica , Dominios Proteicos , Multimerización de Proteína , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Recombinantes de Fusión/metabolismo
10.
Breast Cancer Res Treat ; 189(1): 155-166, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34143359

RESUMEN

PURPOSE: Previous studies have suggested axillary lymph node dissection (ALND) can be omitted in early breast cancer patients undergoing mastectomy with positive lymph nodes (LNs). We assessed the national utilization of ALND and overall survival (OS) for larger, locally advanced tumors in patients undergoing mastectomy with positive LNs. METHODS: The National Cancer Database from 2006 to 2016 was queried for mastectomy patients with clinical T3/T4, N0 tumors, and 1-2 positive LNs. Trends and outcomes for ALND were compared to sentinel lymph node biopsy (SLNB) alone. RESULTS: Thousand nine hundred and seventeen women were included. The proportion of ALND decreased from 70% pre-Z0011 to 52% post-Z0011. On Kaplan-Meier analysis, ALND had better OS compared to SLNB alone (p < 0.01). On multivariate analysis, age (p < 0.01), chemotherapy (p < 0.01), and hormonal therapy (p < 0.01) were associated with better OS. In patients who received adjuvant radiation therapy (ART) ALND improved OS on multivariate analysis (p < 0.01). CONCLUSION: This is the first large database study to demonstrate a national trend to forego ALND in mastectomy patients with large or locally advanced tumors (T3/T4abc) and 1-2 positive lymph nodes. This study suggests a survival benefit for ALND, particularly in patients receiving ART. Careful consideration and further investigations should be performed prior to omitting ALND this patient population.


Asunto(s)
Neoplasias de la Mama , Ganglio Linfático Centinela , Axila , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Mastectomía , Biopsia del Ganglio Linfático Centinela
11.
FASEB J ; 34(6): 8155-8171, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32342547

RESUMEN

Prolonged serum half-life is required for the efficacy of most protein therapeutics. One strategy for half-life extension is to exploit the long circulating half-life of serum albumin by incorporating a binding moiety that recognizes albumin. Here, we describe camelid single-domain antibodies (VH Hs) that bind the serum albumins of multiple species with moderate to high affinity at both neutral and endosomal pH and significantly extend the serum half-lives of multiple proteins in rats from minutes to days. We serendipitously identified an additional VH H (M75) that is naturally pH-sensitive: at endosomal pH, binding affinity for human serum albumin (HSA) was dramatically weakened and binding to rat serum albumin (RSA) was undetectable. Domain mapping revealed that M75 bound to HSA domain 1 and 2. Moreover, alanine scanning of HSA His residues suggested a critical role for His247, located in HSA domain 2, in M75 binding and its pH dependence. Isothermal titration calorimetry experiments were suggestive of proton-linked binding of M75 to HSA, with differing binding enthalpies observed for full-length HSA and an HSA domain 1-domain 2 fusion protein in which surface-exposed His residues were substituted with Ala. M75 conferred moderate half-life extension in rats, from minutes to hours, likely due to rapid dissociation from RSA during FcRn-mediated endosomal recycling in tandem with albumin conformational changes induced by M75 binding that prevented interaction with FcRn. Humanized VH Hs maintained in vivo half-life extension capabilities. These VH Hs represent a new set of tools for extending protein therapeutic half-life and one (M75) demonstrates a unique pH-sensitive binding interaction that can be exploited to achieve modest in vivo half-life.


Asunto(s)
Productos Biológicos/metabolismo , Albúmina Sérica/metabolismo , Animales , Línea Celular , Endosomas/metabolismo , Células HEK293 , Semivida , Humanos , Concentración de Iones de Hidrógeno , Masculino , Unión Proteica/fisiología , Ratas , Ratas Wistar
12.
Mol Pharm ; 18(6): 2375-2384, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-33999642

RESUMEN

Multispecific antibodies that bridge immune effector and tumor cells have shown promising preclinical and clinical efficacies. Here, we isolated and characterized novel llama single-domain antibodies (sdAbs) against CD16. One sdAb, NRC-sdAb048, bound recombinant human and cynomolgus monkey CD16 ectodomains with equivalent affinity (KD: 1 nM) but did not recognize murine CD16. Binding was similar for human CD16a expressed on NK cells and CD16b (NA2) expressed on neutrophils but dramatically weaker (KD: ∼6 µM) for the CD16b (NA1) allotype. The sdAb stained primary human peripheral blood NK cells. Irrespective of fusion orientation and linker length, bispecific sdAb-sdAb and sdAb-scFv dimers (anti-CD16/EGFR, anti-CD16/HER2, and anti-CD16/CD19) retained full binding affinity for each target, coengaged both antigens simultaneously, elicited ADCC against target antigen-expressing tumor cells in a reporter bioassay, and triggered target-specific activation and degranulation of primary NK cells as measured via interferon-γ and CD107a expression. These molecules may have applications in cancer immunotherapy.


Asunto(s)
Anticuerpos Biespecíficos/metabolismo , Células Asesinas Naturales/trasplante , Neoplasias/terapia , Proteínas Recombinantes de Fusión/metabolismo , Anticuerpos de Dominio Único/metabolismo , Animales , Anticuerpos Biespecíficos/genética , Citotoxicidad Celular Dependiente de Anticuerpos , Antígenos de Neoplasias/metabolismo , Bioensayo , Camélidos del Nuevo Mundo , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/genética , Humanos , Inmunoterapia/métodos , Células Jurkat , Células Asesinas Naturales/metabolismo , Macaca fascicularis , Ratones , Neoplasias/inmunología , Cultivo Primario de Células , Dominios Proteicos/genética , Receptores de IgG/antagonistas & inhibidores , Receptores de IgG/genética , Proteínas Recombinantes de Fusión/genética , Anticuerpos de Dominio Único/genética
13.
J Surg Res ; 267: 424-431, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34229130

RESUMEN

BACKGROUND: The primary goal of this study was to demonstrate that endotracheal tubes coated with antimicrobial lipids plus mucolytic or antimicrobial lipids with antibiotics plus mucolytic would significantly reduce pneumonia in the lungs of pigs after 72 hours of continuous mechanical ventilation compared to uncoated controls. MATERIALS AND METHODS: Eighteen female pigs were mechanically ventilated for up to 72 hours through uncoated endotracheal tubes, endotracheal tubes coated with the antimicrobial lipid, octadecylamine, and the mucolytic, N-acetylcysteine, or tubes coated with octadecylamine, N-acetylcysteine, doxycycline, and levofloxacin (6 pigs per group). No exogenous bacteria were inoculated into the pigs, pneumonia resulted from the pigs' endogenous oral flora. Vital signs were recorded every 15 minutes and arterial blood gas measurements were obtained for the duration of the experiment. Pigs were sacrificed either after completion of 72 hours of mechanical ventilation or just prior to hypoxic arrest. Lungs, trachea, and endotracheal tubes were harvested for analysis to include bacterial counts of lung, trachea, and endotracheal tubes, lung wet and dry weights, and lung tissue for histology. RESULTS: Pigs ventilated with coated endotracheal tubes were less hypoxic, had less bacterial colonization of the lungs, and survived significantly longer than pigs ventilated with uncoated tubes. Octadecylamine-N-acetylcysteine-doxycycline-levofloxacin coated endotracheal tubes had less bacterial colonization than uncoated or octadecylamine-N-acetylcysteine coated tubes. CONCLUSION: Endotracheal tubes coated with antimicrobial lipids plus mucolytic and antimicrobial lipids with antibiotics plus mucolytic reduced bacterial colonization of pig lungs after prolonged mechanical ventilation and may be an effective strategy to reduce ventilator-associated pneumonia.


Asunto(s)
Antiinfecciosos , Neumonía Asociada al Ventilador , Animales , Antibacterianos/uso terapéutico , Modelos Animales de Enfermedad , Femenino , Intubación Intratraqueal , Neumonía Asociada al Ventilador/microbiología , Neumonía Asociada al Ventilador/prevención & control , Respiración Artificial/efectos adversos , Porcinos
14.
J Surg Res ; 267: 197-202, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34153562

RESUMEN

INTRODUCTION: Thrombocytosis and leukocytosis are common after splenectomy. The potential effect of emergency surgery on these postoperative findings is unknown. We hypothesized that emergency splenectomy leads to a more profound and persistent hematologic change as compared to elective splenectomy. METHODS: A retrospective review was conducted of patients who underwent elective or trauma splenectomy. Records were queried for platelet (PLT) and white blood cell (WBC) count prior to splenectomy, on postoperative days 1-5, and at day 14, 1 month, 3 months, 6 months, and 1 year. Complications, including thromboembolic events, infection, need for repeat operation, and readmission within 30 days of discharge, were recorded. RESULTS: 463 patients were identified as being eligible for the study, with 173 patients in the elective cohort and 145 patients in each of the isolated trauma splenectomy and polytrauma cohorts. Both cohorts had peak thrombocytosis at week 2 postoperatively. However, polytrauma patients had a significantly higher peak platelet count (P < 0.01). The PLT:WBC ratio was lower in both trauma cohorts pre-operatively and postoperative day 1. Trauma splenectomy had a higher PLT:WBC ratio on days 2 and 3 whereas polytrauma had a lower ratio on days 4 and 5. Emergency cases had greater reoperation and infection rates, whereas elective cases were more likely to require readmission. Postoperative thromboembolic events were only higher in the polytrauma cohort. CONCLUSIONS: While trauma splenectomy resulted in more profound postoperative leukocytosis and thrombocytosis, there was no correlation with timing of infection or risk of thromboembolic events. These findings suggest that thrombocytosis and leukocytosis may be associated with thrombotic and infectious events but their presence alone does not indicate direct risks of concomitant infection or thrombosis.


Asunto(s)
Esplenectomía , Trombocitosis , Humanos , Recuento de Leucocitos , Recuento de Plaquetas , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Esplenectomía/efectos adversos , Trombocitosis/complicaciones , Trombocitosis/etiología
15.
Epilepsy Behav ; 117: 107807, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33610104

RESUMEN

OBJECTIVES: Patients with epilepsy are known to exhibit high rates of comorbid psychiatric disorders such as depression, anxiety, and other mood disorders. Little is known about the psychiatric effects of a ketogenic diet therapy (KDT) on adults with epilepsy. The objective of this study was to better understand the relationship between KDT and psychological state based on depressive and anxiety symptoms in adults with chronic epilepsy. METHODS: Adults at the Johns Hopkins Adult Epilepsy Diet Center on a modified Atkins diet (MAD) for at least one month were surveyed retrospectively. Adults who were diet naïve were given a baseline survey and an additional survey after 3 months or more on MAD. Surveys included validated measures of depressive and anxiety symptoms as well as their severity. Participant demographics, seizure frequency, and use of concomitant antiseizure drugs (ASDs), chronic anxiolytics (excluding as-needed benzodiazepines for seizure rescue only), and/or antidepressant drugs were extracted from electronic medical records. RESULTS: One-hundred participants aged 19-75 enrolled in the study. Sixty participants filled out a single retrospective survey. Of 40 diet naïve participants who filled out a baseline prospective survey, 19 completed a follow-up survey while on MAD and 21 participants were lost to follow-up. Longer diet duration was significantly associated with fewer anxiety and depressive symptoms, based on psychiatric measure scores, in retrospective study participants. Lower seizure frequency was also significantly associated with less anxiety symptoms in the retrospective cohort. Prospective study participants did not experience significant change in anxiety or depressive symptoms on the diet. There was a significant correlation between higher ketone level and responder rate (≥50% seizure reduction) in the prospective cohort, although no correlation between ketone level and change in psychiatric symptoms was seen. SIGNIFICANCE: Psychiatric comorbidity among patients with epilepsy is quite common and can be influenced by multiple factors such as seizure frequency, the use of various ASDs, social factors, and underlying etiology. Although ketogenic diet therapies have been in clinical use for one century, the psychiatric impacts have been insufficiently explored. This study provides preliminary evidence that KDT may have a positive impact on psychological state independent of seizure reduction or ketone body production and may be influenced by longer duration of diet therapy. These results support further investigation into specific effects and potential therapeutic benefits on various psychiatric disorders.


Asunto(s)
Dieta Cetogénica , Epilepsia Refractaria , Epilepsia , Adulto , Anciano , Epilepsia/complicaciones , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
16.
Am J Transplant ; 20(4): 1181-1187, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31605561

RESUMEN

Simultaneous liver-kidney transplantation (SLKT) is indicated for patients with end-stage liver disease (ESLD) and concurrent renal insufficiency. En bloc SLKT is an alternative to traditional separate implantations, but studies comparing the two techniques are limited. The en bloc technique maintains renal outflow via donor infrahepatic vena cava and inflow via anastomosis of donor renal artery to donor splenic artery. Comparison of recipients of en bloc (n = 17) vs traditional (n = 17) SLKT between 2013 and 2017 was performed. Recipient demographics and comorbidities were similar. More recipients of traditional SLKT were dialysis dependent (82.4% vs 41.2%, P = .01) with lower baseline pretransplant eGFR (14 vs 18, P = .01). En bloc SLKT was associated with shorter kidney cold ischemia time (341 vs 533 minutes, P < .01) and operative time (374 vs 511 minutes, P < .01). Two en bloc patients underwent reoperation for kidney allograft inflow issues due to kinking and renal steal. Early kidney allograft dysfunction (23.5% in both groups), 1-year kidney graft survival (88.2% vs 82.4%, P = 1.0), and posttransplantation eGFR were similar between groups. In our experience, the en bloc SLKT technique is safe and feasible, with comparable outcomes to the traditional method.


Asunto(s)
Trasplante de Riñón , Trasplante de Hígado , Supervivencia de Injerto , Humanos , Riñón , Hígado
17.
Artículo en Inglés | MEDLINE | ID: mdl-32015038

RESUMEN

Pseudomonas aeruginosa is an opportunistic pathogen that is inherently resistant to many antibiotics and represents an increasing threat due to the emergence of drug-resistant strains. There is a pressing need to develop innovative antimicrobials against this pathogen. In this study, we identified the O-specific antigen (OSA) of P. aeruginosa serotype O6 as a novel target for therapeutic intervention. Binding of monoclonal antibodies and antigen-binding fragments therefrom to O6 OSA leads to rapid outer membrane destabilization and inhibition of cell growth. The antimicrobial effect correlated directly with antibody affinity. Antibody binding to the O antigen of a second lipopolysaccharide (LPS) type present in P. aeruginosa or to the LPS core did not affect cell viability. Atomic force microscopy showed that antibody binding to OSA resulted in early flagellum loss, formation of membrane blebs, and eventually complete outer membrane loss. We hypothesize that antibody binding to OSA disrupts a key interaction in the P. aeruginosa outer membrane.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales/inmunología , Membrana Externa Bacteriana/patología , Antígenos O/inmunología , Pseudomonas aeruginosa/inmunología , Afinidad de Anticuerpos/inmunología , Flagelos/fisiología , Lipopolisacáridos/inmunología , Microscopía de Fuerza Atómica , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/crecimiento & desarrollo
18.
J Surg Res ; 255: 361-370, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32599456

RESUMEN

BACKGROUND: The ACOSOG Z0011 trial has essentially eliminated axillary lymph node dissection (ALND) in breast conserving therapy (BCT) patients with clinical T1/T2 and 1-2 positive sentinel lymph nodes (SLNs). Currently, ALND is recommended for positive SLNs unless ACOSOG Z0011 criteria are applicable. We aimed to assess the national trends and axillary management before and after the publication of ACOSOG Z0011 for larger tumors. METHODS: An IRB-approved study evaluated the National Cancer Database from 2006 to 2016. Women with clinical T3/T4, N0 who otherwise fit ACOSOG Z0011 criteria were included. Neoadjuvant systemic therapy or known nodal disease was excluded. Clinicopathologic data were compared between two timeframes based on ACOSOZ Z0011 publication and by axillary management. Patients were categorized into SLNB alone (1-5 lymph nodes examined) and ALND (≥10 lymph nodes examined) groups. RESULTS: A total of 230 women fit inclusion criteria, of whom 36% underwent ALND. ALND use decreased from 54% in 2006 to 14% in 2016 (P < 0.01). Comparing ALND to SLNB alone within the pre-Z0011 era, comprehensive community cancer programs had higher proportions of ALND, whereas academic centers had higher rates of SLND alone (P = 0.03). Comparing similar axillary management between eras, SLNB-alone patients in the post-Z0011 era had higher pT and pN stages, were less likely to be Her2 positive, and were more likely to receive systemic treatment. CONCLUSIONS: There is a national trend to forgo ALND in women who have tumors larger than those included in the Z0011 criteria without any clear clinicopathologic indications.


Asunto(s)
Neoplasias de la Mama/terapia , Escisión del Ganglio Linfático/tendencias , Tratamientos Conservadores del Órgano/tendencias , Adulto , Anciano , Axila/cirugía , Mama/patología , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
19.
J Surg Res ; 252: 116-124, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32278965

RESUMEN

BACKGROUND: Proximal (duodenal) small bowel adenocarcinomas have a worse prognosis than distal (jejuno-ileal) tumors, but differences in patient, tumor, and treatment factors between locations remain unclear. METHODS: Patients in the National Cancer Database with surgically resected pathologic stage I-IV small bowel adenocarcinomas between 2004 and 2015 were analyzed. Clinical stage IV patients were excluded. RESULTS: Proximal tumors (n = 3767) were more likely to be higher grade (OR 1.52, CI 1.22-1.85 for moderately; OR 1.83, CI 1.49-2.33 for poorly differentiated, P < 0.01 for both) and have positive lymph nodes (OR 2.04, CI 1.30-3.23, P < 0.01), while distal tumors (n = 3252) were likely to be larger (OR 1.31, CI 1.07-1.60 for size > 5 cm, P < 0.01). Proximal tumors were associated with worse overall survival (OS) and stage-specific survival compared with distal tumors (all P < 0.01). Cox regression analysis of the entire cohort showed worse survival with community versus academic cancer programs, higher comorbidity scores, pathologic stage IV, poorly differentiated histology, positive nodal or margin status, and proximal location, while female gender, larger tumor size, and chemotherapy predicted better survival. On separate Cox regression analyses of each location, neoadjuvant chemotherapy was associated with better OS in the proximal cohort (HR 0.70, CI 0.55-0.88, P < 0.01), while adjuvant chemotherapy was associated with better OS for both proximal (HR 0.49, CI 0.42-0.57, P < 0.01) and distal tumors (HR 0.68, CI 0.57-0.81, P < 0.01). CONCLUSIONS: Proximal small bowel adenocarcinomas are associated with worse overall and stage-specific survival. This may be due to tumor biologic differences as proximal tumors were more likely to have higher grade. Future studies should further investigate differences between proximal and distal tumors to guide targeted treatment algorithms.


Asunto(s)
Adenocarcinoma/mortalidad , Neoplasias Duodenales/mortalidad , Neoplasias del Íleon/mortalidad , Neoplasias del Yeyuno/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/terapia , Anciano , Quimioradioterapia Adyuvante , Neoplasias Duodenales/patología , Neoplasias Duodenales/terapia , Duodeno/patología , Duodeno/cirugía , Femenino , Humanos , Neoplasias del Íleon/patología , Neoplasias del Íleon/terapia , Íleon/patología , Íleon/cirugía , Neoplasias del Yeyuno/patología , Neoplasias del Yeyuno/terapia , Yeyuno/patología , Yeyuno/cirugía , Estimación de Kaplan-Meier , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Tasa de Supervivencia , Resultado del Tratamiento
20.
J Surg Res ; 252: 139-146, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32278968

RESUMEN

BACKGROUND: Age and massive transfusion are predictors of mortality after trauma. We hypothesized that increasing age and high-volume transfusion would result in progressively elevated mortality rates and that a transfusion "ceiling" would define futility. METHODS: The Trauma Quality Improvement Program (TQIP) database was queried for 2013-2016 records and our level I trauma registry was reviewed from 2013 to 2018. Demographic, mortality, and blood transfusion data were collected. Patients were grouped by decade of life and by packed red blood cell (pRBC) transfusion requirement (zero units, 1-3 units, or ≥4 units) within 4 h of admission. RESULTS: TQIP analysis demonstrated an in-hospital mortality risk that increased linearly with age, to an odds ratio of 10.1 in ≥80 y old (P < 0.01). Mortality rates were significantly higher in older adults (P < 0.01) and those with more pRBCs transfused. In massively transfused patients, the transfusion "ceiling" was dependent on age. Owing to the lack granularity in the TQIP database, 230 patients from our institution who received ≥4 units of pRBCs within 4 h of admission were reviewed. On arrival, younger patients had significantly higher heart rates and more severe derangements in lactate levels, base deficits, and pH compared with older patients. There were no differences among age groups in injury severity score, systolic blood pressure, or mortality. CONCLUSIONS: In massively transfused patients, mortality increased with age. However, a significant proportion of older adults were successfully resuscitated. Therefore, age alone should not be considered a contraindication to high-volume transfusion. Traditional physiologic and laboratory criteria indicative of hemorrhagic shock may have reduced reliability with increasing age, and thus providers must have a heightened suspicion for hemorrhage in the elderly. Early transfusion requirements can be combined with age to establish prognosis to define futility to help counsel families regarding mortality after traumatic injury.


Asunto(s)
Transfusión de Eritrocitos/normas , Inutilidad Médica , Resucitación/normas , Choque Hemorrágico/terapia , Heridas y Lesiones/terapia , Adulto , Factores de Edad , Anciano , Toma de Decisiones Clínicas/métodos , Transfusión de Eritrocitos/estadística & datos numéricos , Femenino , Mortalidad Hospitalaria , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Sistema de Registros/estadística & datos numéricos , Resucitación/métodos , Resucitación/estadística & datos numéricos , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Choque Hemorrágico/etiología , Choque Hemorrágico/mortalidad , Centros Traumatológicos/normas , Centros Traumatológicos/estadística & datos numéricos , Resultado del Tratamiento , Estados Unidos/epidemiología , Heridas y Lesiones/complicaciones , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/mortalidad
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