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1.
J Surg Oncol ; 125(8): 1211-1217, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35195923

RESUMEN

OBJECTIVE: To investigate a possible link between breast and thyroid cancer. METHODS: A multicenter retrospective review of patients in the electronic medical records of six Accrual to Clinical Trial (ACT) institutions with both breast cancer and thyroid carcinoma. Each center queried its data using a predefined data dictionary. Information on thyroid and breast cancer included dates of diagnosis, histology, and patient demographics. RESULTS: A random-effects model was used. There were 4.24 million women's records screened, 44 605 with breast cancer and 11 846 with thyroid cancer. The relative risks observed at each institution ranged from 0.49 to 13.47. The combined risk ratio (RR) estimate was 1.77 (95% confidence interval: 0.50-5.18). CONCLUSION: There was no association between the risk of developing thyroid cancer and being a breast cancer survivor compared to no history of breast cancer, but the range of relative risks among the participating institutions was wide. Our findings warrant further study of more institutions with larger sample size. Additionally, further analysis of the significance of regional RR differences may be enlightening.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Tiroides , Neoplasias de la Mama/tratamiento farmacológico , Recolección de Datos , Femenino , Humanos , Riesgo , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/terapia
2.
Infect Immun ; 89(4)2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33468580

RESUMEN

Mutation of purR was previously shown to enhance the virulence of Staphylococcus aureus in a murine sepsis model, and this cannot be fully explained by increased expression of genes within the purine biosynthesis pathway. Rather, the increased production of specific S. aureus virulence factors, including alpha toxin and the fibronectin-binding proteins, was shown to play an important role. Mutation of purR was also shown previously to result in increased abundance of SarA. Here, we demonstrate by transposon sequencing that mutation of purR in the USA300 strain LAC increases fitness in a biofilm while mutation of sarA has the opposite effect. Therefore, we assessed the impact of sarA on reported purR-associated phenotypes by characterizing isogenic purR, sarA, and sarA/purR mutants. The results confirmed that mutation of purR results in increased abundance of alpha toxin, protein A, the fibronectin-binding proteins, and SarA, decreased production of extracellular proteases, an increased capacity to form a biofilm, and increased virulence in an osteomyelitis model. Mutation of sarA had the opposite effects on all of these phenotypes and, other than bacterial burdens in the bone, all of the phenotypes of sarA/purR mutants were comparable to those of sarA mutants. Limiting the production of extracellular proteases reversed all of the phenotypes of sarA mutants and most of those of sarA/purR mutants. We conclude that a critical component defining the virulence of a purR mutant is the enhanced production of SarA, which limits protease production to an extent that promotes the accumulation of critical S. aureus virulence factors.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Endopeptidasas/biosíntesis , Mutación , Proteínas Represoras/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología , Transactivadores/biosíntesis , Factores de Virulencia/genética , Animales , Biopelículas/crecimiento & desarrollo , Elementos Transponibles de ADN , Susceptibilidad a Enfermedades , Espacio Extracelular , Regulación Bacteriana de la Expresión Génica , Ratones , Osteomielitis/microbiología , Staphylococcus aureus/patogenicidad , Virulencia/genética
3.
Infect Immun ; 86(7)2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29661932

RESUMEN

Some members of the genus Chlamydia, including the human pathogen Chlamydia trachomatis, infect multiple tissues, including the genital and gastrointestinal (GI) tracts. However, it is unknown if bacterial targeting to these sites is mediated by multifunctional or distinct chlamydial factors. We previously showed that disruption of individual large clostridial toxin homologs encoded within the Chlamydia muridarum plasticity zone were not critical for murine genital tract infection. Here, we assessed whether cytotoxin genes contribute to C. muridarum GI tropism. Infectivity and shedding of wild-type (WT) C. muridarum and three mutants containing nonsense mutations in different cytotoxin genes, tc0437, tc0438, and tc0439, were compared in mouse genital and GI infection models. One mutant, which had a nonsense mutation in tc0439, was highly attenuated for GI infection and had a GI 50% infectious dose (ID50) that was 1,000 times greater than that of the WT. GI inoculation with this mutant failed to elicit anti-chlamydial antibodies or to protect against subsequent genital tract infection. Genome sequencing of the tc0439 mutant revealed additional chromosomal mutations, and phenotyping of additional mutants suggested that the GI attenuation might be linked to a nonsense mutation in tc0600 The molecular mechanism underlying this dramatic difference in tissue-tropic virulence is not fully understood. However, isolation of these mutants demonstrates that distinct chlamydial chromosomal factors mediate chlamydial tissue tropism and provides a basis for vaccine initiatives to isolate chlamydia strains that are attenuated for genital infection but retain the ability to colonize the GI tract and elicit protective immune responses.


Asunto(s)
Infecciones por Chlamydia/etiología , Chlamydia muridarum/patogenicidad , Cromosomas/fisiología , Enfermedades Gastrointestinales/etiología , Infecciones del Sistema Genital/etiología , Tropismo , Animales , Infecciones por Chlamydia/inmunología , Codón sin Sentido , Citotoxinas/genética , Femenino , Enfermedades Gastrointestinales/inmunología , Tracto Gastrointestinal/microbiología , Genitales/microbiología , Células HeLa , Humanos , Ratones , Ratones Endogámicos C57BL , Especificidad de Órganos , Polimorfismo de Nucleótido Simple , Infecciones del Sistema Genital/inmunología
4.
Ann Vasc Surg ; 46: 112-117, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28546043

RESUMEN

BACKGROUND: Vascular closure devices have been used to achieve hemostasis of percutaneous access sites following endovascular procedures, with reported decreased time for arterial control as well as decreased time to ambulation. We sought to determine rates and risk factors of postoperative bleeding complications and failures using these devices from a single institution experienced in the use of vascular closure devices. METHODS: All patients undergoing arterial endovascular procedures with percutaneous access between March 2010 and October 2015 at a single institution were identified and analyzed (n = 894). Patients undergoing endovascular aneurysm repair, open access, venous procedures, or upper extremity access were excluded. Comparison groups were formed between those using the Mynxgrip® (Mynx), Angio-Seal™, Perclose® vascular closure devices and manual pressure (MP). Patient demographics, intraoperative data, and postoperative complications were compared. RESULTS: A total of 615 (69%) patients received Mynx, 165 other vascular closure devices (VCD) ([14%] Perclose, 44 [4%] Angio-Seal), and 114 (13%) MP. MP patients were more likely to be diagnostic angiogram with smaller sheaths, while VCD patients were more likely to be interventions with larger sheaths. Univariate analysis identified age, atrial fibrillation, intervention (as opposed to diagnostic), and sheath size >5F associated with postoperative bleeding (P < 0.05), and in backward, logistic regression analysis, sheath size, age, and renal failure were independent predictors of the same. CONCLUSIONS: Use of vascular closure devices has a low rate of bleeding complication, device failure, and need for operative repair. Bleeding is associated with increased age, interventional procedure, and end-stage renal disease. Mynx, Perclose, and Angio-Seal have similar rates of complications. Use of these devices are a safe option for groin vessel closure.


Asunto(s)
Arterias/cirugía , Pérdida de Sangre Quirúrgica/prevención & control , Cateterismo Periférico , Procedimientos Endovasculares , Técnicas Hemostáticas/instrumentación , Hemorragia Posoperatoria/prevención & control , Dispositivos de Cierre Vascular , Adulto , Factores de Edad , Anciano , Angiografía , Arkansas , Arterias/diagnóstico por imagen , Cateterismo Periférico/efectos adversos , Comorbilidad , Procedimientos Endovasculares/efectos adversos , Diseño de Equipo , Falla de Equipo , Femenino , Técnicas Hemostáticas/efectos adversos , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Hemorragia Posoperatoria/etiología , Punciones , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
5.
J Vasc Surg ; 65(4): 1121-1129, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28190718

RESUMEN

OBJECTIVE: Aortic graft infection remains a formidable challenge for the vascular surgeon. Traditionally, reconstruction with a neoaortoiliac system (NAIS) involves removal of the entire synthetic graft with in situ reconstruction using femoral vein. Whereas the NAIS procedure is durable with excellent graft patency and a low reinfection rate, it can take up to 10 hours and result in a high perioperative complication rate with significant mortality. Not infrequently, the infection is limited to a single limb. In addition, the patient may be too frail to tolerate aortic clamping for a complete graft excision. Under such circumstances, complete excision of the aortofemoral bypass graft (AFBG) may not be indicated. It is hypothesized that local control of infection and limited reconstruction using femoral vein may be acceptable. The objective of this study was to examine the outcomes of all patients who underwent partial AFBG resection and in situ reconstruction with femoral vein. METHODS: A retrospective review of all AFBG infections from 2003 to 2015 treated at a tertiary care facility was undertaken. Patients who underwent unilateral partial graft excision with inline reconstruction using femoral vein at the distal (femoral) anastomosis were included. Complete excisions with bilateral revascularizations using any conduit or any extra-anatomic reconstructions were excluded. The primary end point was successful treatment of infection. Secondary end points were procedure-related mortality, graft patency, and perioperative complications. RESULTS: During a 12-year period, partial graft excision with bypass using the femoral vein was performed in 21 patients (24 limbs). Mean age was 61 ± 12 years. There were 13 men and 8 women. Mean follow-up was 53 ± 27 months. Successful treatment was achieved in 19 of 21 patients. The two treatment failures were due to persistent infection. One of these patients declined complete graft excision and is receiving lifelong suppressive antibiotic therapy. The other patient underwent complete graft excision and an NAIS reconstruction. There were no perioperative or procedure-related deaths. There were no major amputations, and primary graft patency was 92% at 72 months. The most common AFBG culture isolate was Staphylococcus species. Approximately one-third of cultures did not yield any growth. Patients underwent anywhere from 1 to 12 weeks of combined intravenous and oral antibiotic therapy. CONCLUSIONS: This limited series demonstrates excellent graft patency with a low persistent infection rate. Thus, in patients with localized graft infection, partial excision with preservation of the proximal synthetic graft is an acceptable alternative when patient factors preclude complete graft excision.


Asunto(s)
Aorta/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular/efectos adversos , Remoción de Dispositivos/métodos , Arteria Femoral/cirugía , Vena Femoral/trasplante , Infecciones Relacionadas con Prótesis/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Aorta/diagnóstico por imagen , Aorta/microbiología , Arkansas , Implantación de Prótesis Vascular/mortalidad , Remoción de Dispositivos/efectos adversos , Remoción de Dispositivos/mortalidad , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/microbiología , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/mortalidad , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Centros de Atención Terciaria , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
6.
Acta Obstet Gynecol Scand ; 96(4): 395-409, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28130929

RESUMEN

The aim of this study was to determine, in pregnancies complicated by preterm premature rupture of membranes (PPROM), hypertension, intrauterine growth restriction, multi-fetal gestations and pregnancies 23-26 weeks and ≥34 weeks' gestation, whether antenatal corticosteroids benefit the fetus. Literature review using PubMed, Web of Science, Clinical trials.gov, Cochrane Database of Systematic Reviews (1990-2015). Search terms linked special circumstances with corticosteroids. Randomized clinical trials, retrospective and prospective cohort studies, and case control studies were reviewed. In all, 468 abstracts were identified and 84 added from selected article bibliographies; of these, 503 abstracts were excluded, leaving 49 articles as the basis of review. The literature supports corticosteroids for PPROM up to 32-34 weeks without chorioamnionitis. Antenatal corticosteroids are beneficial for preterm infants of women with HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome/severe preeclampsia. Postpartum corticosteroid treatment of HELLP patients results in more rapid correction of liver enzymes, platelet counts, and urinary output, which can reduce maternal morbidity. Corticosteroids in twin pregnancies decrease respiratory distress syndrome but the effect is less than in singleton pregnancies. Corticosteroid effects on intrauterine growth restriction pregnancies are conflicting and steroid use should be individualized. Corticosteroid use for 23-26 weeks reduces neonatal mortality but not morbidity. In pregnancies of 34 weeks to 366/7  weeks, corticosteroids reduce respiratory distress syndrome, but follow-up studies are unavailable. No long-term adverse child developmental effects have been observed with one or two courses of corticosteroids, but three or more steroid courses lowers birthweight and organ weight, and there may be an increase in neurodevelopmental abnormalities. Longer follow up of corticosteroid-treated fetuses is required.


Asunto(s)
Corticoesteroides/uso terapéutico , Complicaciones del Embarazo , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control , Corticoesteroides/administración & dosificación , Femenino , Rotura Prematura de Membranas Fetales , Humanos , Recién Nacido , Embarazo
7.
J Obstet Gynaecol Res ; 43(7): 1122-1131, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28503779

RESUMEN

AIM: Ultrasound estimation and evaluation of amniotic fluid volume (AFV) is an important component of pregnancy surveillance and fetal well-being. The purpose of this study was to compare and contrast four statistical methods used to construct gestational age-specific reference intervals for the assessment of AFV. METHODS: A total of 1095 normal AFV derived from four studies that measured AFV using dye-dilution or direct measurement at the time of hysterotomy were used to construct reference intervals using polynomial regression, quantile regression, Royston and Wright mean and SD, and Cole's lambda mu sigma (LMS) methods. The 2.5th, 5th, 50th, 95th, and 97.5th centiles were derived for each statistical method. RESULTS: AFV increased curvilinearly from 15 gestational weeks and onward. Based on the 50th centile, the maximum value occurred at 30 weeks' gestation for the polynomial regression and mean and SD methods while the maximum was achieved at week 31 for the quantile regression and LMS methods. When data were sparse, the quantile regression method produced dramatically different estimates at the higher centile. CONCLUSION: The four statistical methods produced similar results at gestational ages in which AFV was high. The quantile regression approach, however, produces results that are more reflective of the data when the data are sparse. Given the flexibility and robustness of the quantile regression method, we recommend its use in constructing reference intervals when the interest lies in the tails of the reference distribution.


Asunto(s)
Líquido Amniótico/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , Femenino , Humanos , Embarazo , Ultrasonografía Prenatal/estadística & datos numéricos
8.
Infect Immun ; 84(4): 1214-1225, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26857575

RESUMEN

We demonstrate that mutation of xerC, which reportedly encodes a homologue of an Escherichia coli recombinase, limits biofilm formation in the methicillin-resistant Staphylococcus aureus strain LAC and the methicillin-sensitive strain UAMS-1. This was not due to the decreased production of the polysaccharide intracellular adhesin (PIA) in either strain because the amount of PIA was increased in a UAMS-1xerC mutant and undetectable in both LAC and its isogenic xerC mutant. Mutation of xerC also resulted in the increased production of extracellular proteases and nucleases in both LAC and UAMS-1, and limiting the production of either class of enzymes increased biofilm formation in the isogenic xerC mutants. More importantly, the limited capacity to form a biofilm was correlated with increased antibiotic susceptibility in both strains in the context of an established biofilm in vivo. Mutation of xerC also attenuated virulence in a murine bacteremia model, as assessed on the basis of the bacterial loads in internal organs and overall lethality. It also resulted in the decreased accumulation of alpha toxin and the increased accumulation of protein A. These findings suggest that xerC may impact the functional status of agr. This was confirmed by demonstrating the reduced accumulation of RNAIII and AgrA in LAC and UAMS-1xerC mutants. However, this cannot account for the biofilm-deficient phenotype of xerC mutants because mutation of agr did not limit biofilm formation in either strain. These results demonstrate that xerC contributes to biofilm-associated infections and acute bacteremia and that this is likely due to agr-independent and -dependent pathways, respectively.


Asunto(s)
Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Péptidos Cíclicos/metabolismo , Recombinasas/metabolismo , Staphylococcus aureus/enzimología , Proteínas Bacterianas/genética , Staphylococcus aureus Resistente a Meticilina/enzimología , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/metabolismo , Mutación , Operón , Péptidos Cíclicos/genética , Recombinasas/genética , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
9.
Am J Physiol Endocrinol Metab ; 310(1): E73-80, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26530155

RESUMEN

We have determined whole body protein kinetics, i.e., protein synthesis (PS), breakdown (PB), and net balance (NB) in human subjects in the fasted state and following ingestion of ~40 g [moderate protein (MP)], which has been reported to maximize the protein synthetic response or ~70 g [higher protein (HP)] protein, more representative of the amount of protein in the dinner of an average American diet. Twenty-three healthy young adults who had performed prior resistance exercise (X-MP or X-HP) or time-matched resting (R-MP or R-HP) were studied during a primed continuous infusion of l-[(2)H5]phenylalanine and l-[(2)H2]tyrosine. Subjects were randomly assigned into an exercise (X, n = 12) or resting (R, n = 11) group, and each group was studied at the two levels of dietary protein intake in random order. PS, PB, and NB were expressed as increases above the basal, fasting values (mg·kg lean body mass(-1)·min(-1)). Exercise did not significantly affect protein kinetics and blood chemistry. Feeding resulted in positive NB at both levels of protein intake: NB was greater in response to the meal containing HP vs. MP (P < 0.00001). The greater NB with HP was achieved primarily through a greater reduction in PB and to a lesser extent stimulation of protein synthesis (for all, P < 0.0001). HP resulted in greater plasma essential amino acid responses (P < 0.01) vs. MP, with no differences in insulin and glucose responses. In conclusion, whole body net protein balance improves with greater protein intake above that previously suggested to maximally stimulating muscle protein synthesis because of a simultaneous reduction in protein breakdown.


Asunto(s)
Proteínas en la Dieta/metabolismo , Proteínas en la Dieta/farmacología , Comidas , Biosíntesis de Proteínas/efectos de los fármacos , Adolescente , Adulto , Composición Corporal/efectos de los fármacos , Ejercicio Físico/fisiología , Femenino , Voluntarios Sanos , Humanos , Masculino , Metabolismo/efectos de los fármacos , Proteínas Musculares/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Distribución Aleatoria , Entrenamiento de Fuerza , Adulto Joven
10.
Antimicrob Agents Chemother ; 60(10): 5688-94, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27401574

RESUMEN

We used in vitro and in vivo models of catheter-associated biofilm formation to compare the relative activity of antibiotics effective against methicillin-resistant Staphylococcus aureus (MRSA) in the specific context of an established biofilm. The results demonstrated that, under in vitro conditions, daptomycin and ceftaroline exhibited comparable activity relative to each other and greater activity than vancomycin, telavancin, oritavancin, dalbavancin, or tigecycline. This was true when assessed using established biofilms formed by the USA300 methicillin-resistant strain LAC and the USA200 methicillin-sensitive strain UAMS-1. Oxacillin exhibited greater activity against UAMS-1 than LAC, as would be expected, since LAC is an MRSA strain. However, the activity of oxacillin was less than that of daptomycin and ceftaroline even against UAMS-1. Among the lipoglycopeptides, telavancin exhibited the greatest overall activity. Specifically, telavancin exhibited greater activity than oritavancin or dalbavancin when tested against biofilms formed by LAC and was the only lipoglycopeptide capable of reducing the number of viable bacteria below the limit of detection. With biofilms formed by UAMS-1, telavancin and dalbavancin exhibited comparable activity relative to each other and greater activity than oritavancin. Importantly, ceftaroline was the only antibiotic that exhibited greater activity than vancomycin when tested in vivo in a murine model of catheter-associated biofilm formation. These results emphasize the need to consider antibiotics other than vancomycin, most notably, ceftaroline, for the treatment of biofilm-associated S. aureus infections, including by the matrix-based antibiotic delivery methods often employed for local antibiotic delivery in the treatment of these infections.


Asunto(s)
Antibacterianos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Aminoglicósidos/farmacología , Animales , Biopelículas/efectos de los fármacos , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/microbiología , Evaluación Preclínica de Medicamentos/métodos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Glicopéptidos/farmacología , Lipoglucopéptidos , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Ratones , Pruebas de Sensibilidad Microbiana , Teicoplanina/análogos & derivados , Teicoplanina/farmacología
11.
Antimicrob Agents Chemother ; 60(3): 1826-9, 2016 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-26824954

RESUMEN

We previously determined the extent to which mutations of different Staphylococcus aureus regulatory loci impact biofilm formation as assessed under in vitro conditions. Here we extend these studies to determine the extent to which those regulatory loci that had the greatest effect on biofilm formation also impact antibiotic susceptibility. The experiments were done under in vitro and in vivo conditions using two clinical isolates of S. aureus (LAC and UAMS-1) and two functionally diverse antibiotics (daptomycin and ceftaroline). Mutation of the staphylococcal accessory regulator (sarA) or sigB was found to significantly increase susceptibilities to both antibiotics and in both strains in a manner that could not be explained by changes in the MICs. The impact of a mutation in sarA was comparable to that of a mutation in sigB and greater than the impact observed with any other mutant. These results suggest that therapeutic strategies targeting sarA and/or sigB have the greatest potential to facilitate the ability to overcome the intrinsic antibiotic resistance that defines S. aureus biofilm-associated infections.


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/genética , Biopelículas/efectos de los fármacos , Cefalosporinas/farmacología , Daptomicina/farmacología , Factor sigma/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , Animales , Biopelículas/crecimiento & desarrollo , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/microbiología , Catéteres/microbiología , Farmacorresistencia Bacteriana/genética , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/patogenicidad , Ceftarolina
12.
Cancer Immunol Immunother ; 65(5): 563-73, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26980480

RESUMEN

In the dose-escalation phase of a Phase I clinical trial in which six subjects each were vaccinated with PepCan at the 50, 100, 250, and 500 µg per peptide dose, the 50 µg dose showed the best histological regression rate. Ten additional subjects were vaccinated at this dose in the final dose phase. As with the dose-escalation phase, no dose-limiting toxicities were observed. Overall, the histological regression rates were 50% at the 50 µg dose (7 of 14) and 100 µg dose (3 of 6), and 45 % overall (14 of 31). Of subjects in whom HPV type 16 (HPV 16) was detected at entry, it became undetectable in three subjects after vaccination, and the viral loads significantly decreased in nine subjects in whom HPV 16 infection was detected at entry and exit (p = 0.008). Immune profiling revealed increased T-helper type 1 cells after vaccinations (p = 0.02 and 0.0004 after 2 and 4 vaccinations, respectively). T-helper type 2 cells initially increased after two vaccinations (p = 0.01), but decreased below the baseline level after four vaccinations although not significantly. Pre-vaccination regulatory T cell levels were significantly lower in histological responders compared to non-responders (p = 0.03). Feasibility of testing plasma for multiplex cytokine/chemokine analysis and of performing proteomic analysis of PBMCs was examined for potentially identifying biomarkers in the future. While these analyses are feasible to perform, attention needs to be given to how soon the blood samples would be processed after phlebotomy. As sufficient safety of PepCan has been demonstrated, enrollment for the Phase II clinical trial has been opened.


Asunto(s)
Papillomavirus Humano 16/inmunología , Infecciones por Papillomavirus/inmunología , Neoplasias del Cuello Uterino/inmunología , Carga Viral/inmunología , Adulto , Cromatografía Liquida , Citocinas/sangre , Citocinas/inmunología , Relación Dosis-Respuesta a Droga , Femenino , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/inmunología , Papillomavirus Humano 16/efectos de los fármacos , Papillomavirus Humano 16/fisiología , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Persona de Mediana Edad , Infecciones por Papillomavirus/tratamiento farmacológico , Infecciones por Papillomavirus/virología , Proteoma/inmunología , Proteoma/metabolismo , Proteómica/métodos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Espectrometría de Masas en Tándem , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/virología , Vacunación/métodos , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/uso terapéutico , Carga Viral/efectos de los fármacos , Adulto Joven
13.
BMC Dev Biol ; 15: 15, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25888190

RESUMEN

BACKGROUND: There is increasing evidence of a pivotal role for regulated mRNA translation in control of developmental cell fate transitions. Physiological and pathological stem and progenitor cell self-renewal is maintained by the mRNA-binding protein, Musashi1 through repression of translation of key mRNAs encoding cell cycle inhibitory proteins. The mechanism by which Musashi1 function is modified to allow translation of these target mRNAs under conditions that require inhibition of cell cycle progression, is unknown. RESULTS: In this study, we demonstrate that differentiation of primary embryonic rat neural stem/progenitor cells (NSPCs) or human neuroblastoma SH-SY5Y cells results in the rapid phosphorylation of Musashi1 on the evolutionarily conserved site serine 337 (S337). Phosphorylation of this site has been shown to be required for cell cycle control during the maturation of Xenopus oocytes. S337 phosphorylation in mammalian NSPCs and human SH-SY5Y cells correlates with the de-repression and translation of a Musashi reporter mRNA and with accumulation of protein from the endogenous Musashi target mRNA, p21(WAF1/CIP1). Inhibition of Musashi regulatory phosphorylation, through expression of a phospho-inhibitory mutant Musashi1 S337A or over-expression of the wild-type Musashi, blocked differentiation of both NSPCs and SH-SY5Y cells. Musashi1 was similarly phosphorylated in NSPCs and SH-SY5Y cells under conditions of nutrient deprivation-induced cell cycle arrest. Expression of the Musashi1 S337A mutant protein attenuated nutrient deprivation-induced NSPC and SH-SY5Y cell death. CONCLUSIONS: Our data suggest that in response to environmental cues that oppose cell cycle progression, regulation of Musashi function is required to promote target mRNA translation and cell fate transition. Forced modulation of Musashi1 function may present a novel therapeutic strategy to oppose pathological stem cell self-renewal.


Asunto(s)
Diferenciación Celular/fisiología , Linaje de la Célula , Proteínas del Tejido Nervioso/fisiología , Células-Madre Neurales/citología , Proteínas de Unión al ARN/fisiología , Animales , Línea Celular Tumoral , Células Cultivadas , Humanos , Fosforilación , Ratas
14.
Am J Physiol Endocrinol Metab ; 309(11): E915-24, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26442881

RESUMEN

To determine if age-associated vascular dysfunction in older adults with heart failure (HF) is due to insufficient synthesis of nitric oxide (NO), we performed two separate studies: 1) a kinetic study with a stable isotope tracer method to determine in vivo kinetics of NO metabolism, and 2) a vascular function study using a plethysmography method to determine reactive hyperemic forearm blood flow (RH-FBF) in older and young adults in the fasted state and in response to citrulline ingestion. In the fasted state, NO synthesis (per kg body wt) was ∼ 50% lower in older vs. young adults and was related to a decreased rate of appearance of the NO precursor arginine. Citrulline ingestion (3 g) stimulated de novo arginine synthesis in both older [6.88 ± 0.83 to 35.40 ± 4.90 µmol · kg body wt(-1) · h(-1)] and to a greater extent in young adults (12.02 ± 1.01 to 66.26 ± 4.79 µmol · kg body wt(-1) · h(-1)). NO synthesis rate increased correspondingly in older (0.17 ± 0.01 to 2.12 ± 0.36 µmol · kg body wt(-1) · h(-1)) and to a greater extent in young adults (0.36 ± 0.04 to 3.57 ± 0.47 µmol · kg body wt(-1) · h(-1)). Consistent with the kinetic data, RH-FBF in the fasted state was ∼ 40% reduced in older vs. young adults. However, citrulline ingestion (10 g) failed to increase RH-FBF in either older or young adults. In conclusion, citrulline ingestion improved impaired NO synthesis in older HF adults but not RH-FBF, suggesting that factors other than NO synthesis play a role in the impaired RH-FBF in older HF adults, and/or it may require a longer duration of supplementation to be effective in improving RH-FBF.


Asunto(s)
Fármacos Cardiovasculares/uso terapéutico , Citrulina/uso terapéutico , Suplementos Dietéticos , Fenómenos Fisiológicos Nutricionales del Anciano , Insuficiencia Cardíaca/dietoterapia , Óxido Nítrico/agonistas , Regulación hacia Arriba , Adulto , Anciano , Arginina/sangre , Arginina/metabolismo , Fármacos Cardiovasculares/efectos adversos , Citrulina/efectos adversos , Suplementos Dietéticos/efectos adversos , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Femenino , Antebrazo , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Humanos , Hiperemia/etiología , Cinética , Masculino , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico/metabolismo , Flujo Sanguíneo Regional , Índice de Severidad de la Enfermedad , Adulto Joven
15.
Mol Microbiol ; 92(6): 1299-312, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24779437

RESUMEN

We investigated the in vivo relevance of the impact of sarA and saeRS on protease production using derivatives of the USA300 strain LAC. The results confirmed that mutation of saeRS or sarA reduces virulence in a bacteremia model to a comparable degree. However, while eliminating protease production restored virulence in the sarA mutant, it had little impact in the saeRS mutant. Additionally, constitutive activation of saeRS (saeRS(C)) enhanced the virulence of LAC and largely restored virulence in the isogenic sarA mutant. Based on these results, together with our analysis of the representative virulence factors alpha toxin, protein A (Spa), and extracellular nucleases, we propose a model in which the attenuation of saeRS mutants is defined primarily by decreased production of such factors, while constitutive activation of saeRS increases virulence, and reverses the attenuation of sarA mutants, because it results in both increased production and decreased protease-mediated degradation of these same factors. This regulatory balance was also apparent in a murine model of catheter-associated infection, with the results suggesting that the impact of saeRS on nuclease production plays an important role during the early stages of these infections that is partially offset by increased protease production in sarA mutants.


Asunto(s)
Proteínas Bacterianas/metabolismo , Staphylococcus aureus Resistente a Meticilina/enzimología , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Péptido Hidrolasas/metabolismo , Proteínas Quinasas/metabolismo , Animales , Bacteriemia/microbiología , Bacteriemia/patología , Proteínas Bacterianas/genética , Infecciones Relacionadas con Catéteres/microbiología , Infecciones Relacionadas con Catéteres/patología , Modelos Animales de Enfermedad , Ratones , Factores de Transcripción , Virulencia
16.
Clin Trials ; 12(3): 199-204, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25576067

RESUMEN

BACKGROUND: Historically, recruitment and retention of young women in intervention-based clinical trials have been challenging. In August 2012, enrollment for a clinical trial testing of an investigational human papillomavirus therapeutic vaccine called PepCan was opened at our institution. This study was an open-label, single-arm, single-institution, dose-escalation Phase I clinical trial. Women with recent Papanicolaou smear results showing high-grade squamous intraepithelial lesions or results that could not rule out high-grade squamous intraepithelial lesion were eligible to enroll. Patients with biopsy-confirmed high-grade squamous intraepithelial lesion were also eligible. Colposcopy was performed at the screening visit, and participants became eligible for vaccination when the diagnosis of high-grade squamous intraepithelial lesion was confirmed with biopsy and other inclusion criteria were met. The aim of this study was to identify strategies and factors effective in recruitment and retention of study participants. METHODS: Potential vaccine candidates were recruited through direct advertisement as well as referrals, including referrals through the Arkansas telecolposcopy network. The network is a federally funded program, administered by physicians and advanced practice nurses. The network telemedically links rural health sites and allows physician-guided colposcopy and biopsies to be conducted by advanced practice nurses. A variety of strategies were employed to assure good retention, including face-to-face contact with the study coordinator at the time of consent and most of study visits; frequent contact using text messaging, phone calls, and e-mails; and creation of a private Facebook page to improve communication among research staff and study participants. A questionnaire, inquiring about motivation for joining the study, occupation, education, household income, number of children, and number of sexual partners, was administered at the screening visit with the intent of identifying factor(s) associated with recruitment and retention. RESULTS: A total of 37 participants were enrolled between September 2012 and March 2014. The largest proportion of participants (46%) was enrolled from the telecolposcopy network. Others were enrolled through outside institutions (43%), in-house referrals (8%), or direct advertisement (3%). Most participants were motivated to join the study to take care of their health issues. Only two participants joined the Facebook private page. Of the 24 participants who qualified for vaccination, only 1 terminated early due to an unanticipated move. CONCLUSION: The availability of a large number of potential participants from the telecolposcopy network increased recruitment to this clinical trial by 85% over other traditional means of recruitment. The telecolposcopy network is not only a means of providing a gynecological service to women who otherwise would forego care but also a novel and valuable resource in recruiting participants for a clinical trial.


Asunto(s)
Colposcopía/métodos , Vacunas contra Papillomavirus/administración & dosificación , Selección de Paciente , Lesiones Intraepiteliales Escamosas de Cuello Uterino/diagnóstico , Telemedicina/organización & administración , Adulto , Comunicación , Femenino , Humanos , Persona de Mediana Edad , Prueba de Papanicolaou , Proyectos de Investigación , Servicios de Salud Rural/organización & administración , Factores Socioeconómicos
17.
Infect Immun ; 82(10): 4292-306, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25069985

RESUMEN

The Lyme disease spirochete, Borrelia burgdorferi, occupies both a tick vector and mammalian host in nature. Considering the unique enzootic life cycle of B. burgdorferi, it is not surprising that a large proportion of its genome is composed of hypothetical proteins not found in other bacterial pathogens. bb0238 encodes a conserved hypothetical protein of unknown function that is predicted to contain a tetratricopeptide repeat (TPR) domain, a structural motif responsible for mediating protein-protein interactions. To evaluate the role of bb0238 during mammalian infection, a bb0238-deficient mutant was constructed. The bb0238 mutant was attenuated in mice infected via needle inoculation, and complementation of bb0238 expression restored infectivity to wild-type levels. bb0238 expression does not change in response to varying culture conditions, and thus, it appears to be constitutively expressed under in vitro conditions. bb0238 is expressed in murine tissues during infection, though there was no significant change in expression levels among different tissue types. Localization studies indicate that BB0238 is associated with the inner membrane of the spirochete and is therefore unlikely to promote interaction with host ligands during infection. B. burgdorferi clones containing point mutations in conserved residues of the putative TPR motif of BB0238 demonstrated attenuation in mice that was comparable to that in the bb0238 deletion mutant, suggesting that BB0238 may contain a functional TPR domain.


Asunto(s)
Proteínas Bacterianas/metabolismo , Borrelia burgdorferi/patogenicidad , Enfermedad de Lyme/microbiología , Factores de Virulencia/metabolismo , Animales , Proteínas Bacterianas/genética , Borrelia burgdorferi/genética , Análisis Mutacional de ADN , Modelos Animales de Enfermedad , Femenino , Eliminación de Gen , Prueba de Complementación Genética , Ratones , Ratones Endogámicos C3H , Mutación Puntual , Ratas Sprague-Dawley , Factores de Virulencia/genética
18.
Arch Gynecol Obstet ; 289(5): 967-72, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24241077

RESUMEN

PURPOSE: To develop uniform and reliable reference ranges for amniotic fluid volume (AFV) across gestation in normal singleton pregnancies using quantile regression (QR). METHODS: An analysis of true AFVs determined by dye-dilution techniques or by direct measurement at cesarean delivery in normal singleton pregnancies. AFV centiles were established by QR, a flexible semi-parametric approach of estimating rates of change across the entire distribution of AFV rather than just in the mean as is observed with standard linear regression. RESULTS: The study evaluated 379 women with normal singleton pregnancies between 16 and 41 weeks gestation. QR was used to determine the association between AFV and gestational age (GA). A second-order quantile regression model indicated a nonlinear relationship between AFV and gestational age at the upper centile range (≥80th percentile). CONCLUSION: This study defines normative centile charts for true AFVs between 16 and 41 weeks gestation in normal singleton pregnancies using QR. This statistical approach more appropriately reflects true AFV across gestation at each centile of interest (e.g. 5th, 50th, 95th, etc.) as compared to standard linear regression.


Asunto(s)
Líquido Amniótico/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , Cesárea , Técnica de Dilución de Colorante , Femenino , Edad Gestacional , Humanos , Mississippi , Oligohidramnios/diagnóstico por imagen , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Valores de Referencia , Análisis de Regresión
19.
Anticancer Res ; 44(1): 151-155, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38160002

RESUMEN

BACKGROUND/AIM: Opioids are a common treatment for cancer-related pain and information is limited on the rates of opioid use for cervical cancer patients. This study aimed to analyze outpatient opioid use and various predictors among patients with cervical cancer at a tertiary academic medical center. PATIENTS AND METHODS: Data from patients with cervical cancer receiving treatment at a single institution, from August 2019 to July 2022, were retrospectively collected. Women with unrelated chronic opioid use or opioid use associated with acute inpatient stays were excluded. Charts were reviewed for patient demographics, disease characteristics, treatment characteristics, disease outcomes, and opioid prescriptions. The primary endpoint was duration of opioid use ≥6 months. Pearson's chi-squared testing, Welch's two-sample t-testing and Fisher's exact testing were used to determine predictors of opioid use ≥6 months. RESULTS: In total, 108 patients with cervical cancer (76.1%) of the 142 that received treatment were prescribed opioids. In women who were prescribed outpatient opioids, the median duration of opioid use was 69 days (interquartile range=5-359 days). In total, 40 (37.0%) had prescriptions for ≥180 days and 27 (25.0%) had prescriptions ≥365 days. On bivariate analysis, lower stage and receipt of surgery were associated with opioid use duration <6 months. Age, race, histology, substance/tobacco/alcohol use, depression/anxiety, and the receipt of brachytherapy/radiation were not associated with length of opioid prescriptions. CONCLUSION: This study demonstrated that 37% of patients with cervical cancer were using opioids for cancer-related pain longer than 6 months. Higher stage was associated with opioid use duration ≥6 months.


Asunto(s)
Dolor en Cáncer , Trastornos Relacionados con Sustancias , Neoplasias del Cuello Uterino , Humanos , Femenino , Analgésicos Opioides/efectos adversos , Estudios Retrospectivos , Dolor en Cáncer/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Centros Médicos Académicos , Pautas de la Práctica en Medicina , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología
20.
Microbiol Spectr ; 12(1): e0314723, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38059629

RESUMEN

IMPORTANCE: Because biofilm formation is such a problematic feature of Staphylococcus aureus infections, much effort has been put into identifying biofilm inhibitors. However, the results observed with these compounds are often reported in isolation, and the methods used to assess biofilm formation vary between labs, making it impossible to assess relative efficacy and prioritize among these putative inhibitors for further study. The studies we report address this issue by directly comparing putative biofilm inhibitors using a consistent in vitro assay. This assay was previously shown to maximize biofilm formation, and the results observed with this assay have been proven to be relevant in vivo. Of the 19 compounds compared using this method, many had no impact on biofilm formation under these conditions. Indeed, only one proved effective at limiting biofilm formation without also inhibiting growth.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Biopelículas , Proyectos de Investigación , Pruebas de Sensibilidad Microbiana
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