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1.
Mol Cancer Ther ; 22(2): 192-204, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36722142

RESUMEN

Aberrant cell-cycle progression is characteristic of melanoma, and CDK4/6 inhibitors, such as palbociclib, are currently being tested for efficacy in this disease. Despite the promising nature of CDK4/6 inhibitors, their use as single agents in melanoma has shown limited clinical benefit. Herein, we discovered that treatment of tumor cells with palbociclib induces the phosphorylation of the mRNA translation initiation factor eIF4E. When phosphorylated, eIF4E specifically engenders the translation of mRNAs that code for proteins involved in cell survival. We hypothesized that cancer cells treated with palbociclib use upregulated phosphorylated eIF4E (phospho-eIF4E) to escape the antitumor benefits of this drug. Indeed, we found that pharmacologic or genetic disruption of MNK1/2 activity, the only known kinases for eIF4E, enhanced the ability of palbociclib to decrease clonogenic outgrowth. Moreover, a quantitative proteomics analysis of melanoma cells treated with combined MNK1/2 and CDK4/6 inhibitors showed downregulation of proteins with critical roles in cell-cycle progression and mitosis, including AURKB, TPX2, and survivin. We also observed that palbociclib-resistant breast cancer cells have higher basal levels of phospho-eIF4E, and that treatment with MNK1/2 inhibitors sensitized these palbociclib-resistant cells to CDK4/6 inhibition. In vivo we demonstrate that the combination of MNK1/2 and CDK4/6 inhibition significantly increases the overall survival of mice compared with either monotherapy. Overall, our data support MNK1/2 inhibitors as promising drugs to potentiate the antineoplastic effects of palbociclib and overcome therapy-resistant disease.


Asunto(s)
Neoplasias de la Mama , Melanoma , Inhibidores de Proteínas Quinasas , Animales , Ratones , Factor 4E Eucariótico de Iniciación , Melanoma/tratamiento farmacológico , Piperazinas/farmacología , Piridinas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Antineoplásicos/farmacología
3.
Clin Ophthalmol ; 16: 2137-2144, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35800673

RESUMEN

Purpose: To evaluate efficacy of a novel risk stratification system in minimizing resident surgical complications and to evaluate whether the system could be used to safely introduce cataract surgery to earlier levels of training. Materials and Methods: This is a retrospective cross-sectional study on 530 non-consecutive cataract cases performed by residents at Columbia University. Risk scores, preoperative best corrected visual acuity (BCVA), intraoperative complications, postoperative day 1 (POD1), and month 1 (POM1) exam findings were tabulated. The relationship between risk scores and POD1 and POM1 BCVA was modeled using linear regression. The relationship between risk scores and complication rates was modeled using logistic regression. Logistic regression was used to model the rates of complications across different levels of training. Rates of complications were compared between diabetic versus non-diabetic patients using t-tests. Results: Risk scores did not have significant association with intraoperative complications. Risk scores were predictive of corneal edema (OR = 1.36, p = 0.0032) and having any POM1 complication (OR = 1.20, p = 0.034). Risk scores were predictive of POD1 (ß = 0.13, p < 0.0001) and POM1 (ß = 0.057, p = 0.00048) visual acuity. There was no significant association between level of training and rates of intraoperative (p = 0.9) or postoperative complications (p = 0.06). Rates of intraoperative complication trended higher among diabetic patients but was not statistically significant (p = 0.2). Conclusion: Higher risk scores were predictive of prolonged corneal edema but not risk of intraoperative complications. Our risk stratification system allowed us to safely introduce earlier phacoemulsification surgery.

4.
Conserv Physiol ; 10(1): coac002, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35492414

RESUMEN

Rising ocean temperatures are pushing reef-building corals beyond their temperature optima (Topt ), resulting in reduced physiological performances and increased risk of bleaching. Identifying refugia with thermally resistant corals and understanding their thermal adaptation strategy is therefore urgent to guide conservation actions. The Gulf of Aqaba (GoA, northern Red Sea) is considered a climate refuge, hosting corals that may originate from populations selected for thermal resistance in the warmer waters of the Gulf of Tadjoura (GoT, entrance to the Red Sea and 2000 km south of the GoA). To better understand the thermal adaptation strategy of GoA corals, we compared the temperature optima (Topt ) of six common reef-building coral species from the GoA and the GoT by measuring oxygen production and consumption rates as well as photophysiological performance (i.e. chlorophyll fluorescence) in response to a short heat stress. Most species displayed similar Topt between the two locations, highlighting an exceptional continuity in their respective physiological performances across such a large latitudinal range, supporting the GoA refuge theory. Stylophora pistillata showed a significantly lower Topt in the GoA, which may suggest an ongoing population-level selection (i.e. adaptation) to the cooler waters of the GoA and subsequent loss of thermal resistance. Interestingly, all Topt were significantly above the local maximum monthly mean seawater temperatures in the GoA (27.1°C) and close or below in the GoT (30.9°C), indicating that GoA corals, unlike those in the GoT, may survive ocean warming in the next few decades. Finally, Acropora muricata and Porites lobata displayed higher photophysiological performance than most species, which may translate to dominance in local reef communities under future thermal scenarios. Overall, this study is the first to compare the Topt of common reef-building coral species over such a latitudinal range and provides insights into their thermal adaptation in the Red Sea.

5.
Sci Rep ; 12(1): 2585, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35173191

RESUMEN

Within the next 1.5 decades, 1 in 7 U.S. adults is anticipated to suffer from age-related macular degeneration (AMD), a degenerative retinal disease which leads to blindness if untreated. Optical coherence tomography angiography (OCTA) has become a prime technique for AMD diagnosis, specifically for late-stage neovascular (NV) AMD. Such technologies generate massive amounts of data, challenging to parse by experts alone, transforming artificial intelligence into a valuable partner. We describe a deep learning (DL) approach which achieves multi-class detection of non-AMD vs. non-neovascular (NNV) AMD vs. NV AMD from a combination of OCTA, OCT structure, 2D b-scan flow images, and high definition (HD) 5-line b-scan cubes; DL also detects ocular biomarkers indicative of AMD risk. Multimodal data were used as input to 2D-3D Convolutional Neural Networks (CNNs). Both for CNNs and experts, choroidal neovascularization and geographic atrophy were found to be important biomarkers for AMD. CNNs predict biomarkers with accuracy up to 90.2% (positive-predictive-value up to 75.8%). Just as experts rely on multimodal data to diagnose AMD, CNNs also performed best when trained on multiple inputs combined. Detection of AMD and its biomarkers from OCTA data via CNNs has tremendous potential to expedite screening of early and late-stage AMD patients.


Asunto(s)
Testimonio de Experto , Degeneración Macular/diagnóstico por imagen , Redes Neurales de la Computación , Tomografía de Coherencia Óptica/métodos , Biomarcadores , Neovascularización Coroidal/diagnóstico por imagen , Aprendizaje Profundo , Diagnóstico Diferencial , Humanos , Valor Predictivo de las Pruebas , Curva ROC , Riesgo , Índice de Severidad de la Enfermedad
6.
J Acad Ophthalmol (2017) ; 14(2): e153-e165, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37388175

RESUMEN

Purpose Prior studies have revealed grading discrepancies in evaluation of personal statements and letters of recommendation based on candidate's race and gender. Fatigue and the end-of-day phenomenon can negatively impact task performance but have not been studied in the residency selection process. Our primary objective is to determine whether factors related to interview time and day as well as candidate's and interviewer's gender have a significant effect on residency interview scores. Methods Seven years of ophthalmology residency candidate evaluation scores from 2013 to 2019 were collected at a single academic institution, standardized by interviewer into relative percentiles (0-100 point grading scale), and grouped into the following categories for comparisons: different interview days (Day 1 vs. Day 2), morning versus afternoon (AM vs. PM), interview session (Day 1 AM/PM vs. Day 2 AM/PM), before and after breaks (morning break, lunch break, and afternoon break), residency candidate's gender, and interviewer's gender. Results Candidates in the morning sessions were found to have higher scores than afternoon sessions (52.75 vs. 49.28, p < 0.001). Interview scores in the early morning, late morning, and early afternoon were higher than late afternoon scores (54.47, 53.01, 52.15 vs. 46.74, p < 0.001). Across all interview years, there were no differences in scores received before and after morning breaks (51.71 vs. 52.83, p = 0.49), lunch breaks (53.01 vs. 52.15, p = 0.58), and afternoon breaks (50.35 vs. 48.30, p = 0.21). No differences were found in scores received by female versus male candidates (51.55 vs. 50.49, p = 0.21) or scores given by female versus male interviewers (51.31 vs. 50.84, p = 0.58). Conclusion Afternoon residency candidate interview scores, especially late afternoon, were significantly lower than morning scores, suggesting the need to further study the effects of interviewer's fatigue in the residency interview process. The interview day, presence of break times, candidate's gender, and interviewer's gender had no significant effects on interview score.

7.
J Glob Health ; 11: 05022, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34671463

RESUMEN

BACKGROUND: This study sought to determine the presence of SARS-CoV-2 virus on surfaces that trainees and faculty of an academic eye clinic came into contact with during daily life at the time of the COVID-19 pandemic in New York City. METHODS: This cross-sectional analysis involved collection of at least two samples by teams on four different days (November 9, 2020 - December 18, 2020) using sterile swabs (Puritan HydraFlock, Garden Grove, CA). Collection sites were grouped into four zones depending on proximity and amount of time personnel spent there. Samples were transported to the laboratory in transport medium and RNA was extracted using the QIAamp DSP Viral RNA Mini Kit (Qiagen, Germantown, MD). Presence of viral RNA was investigated using the Luna Universal Probe One-step RT-qPCR kit (New England Biolabs, Ipwsich, MA). RESULTS: 834 samples were submitted. Two were positive for SARS-CoV-2 RNA. The first was a sample from a patient bathroom sink handle in the main emergency department. The second was a nasal swab sample from a staff member who had been assigned to collect samples. Prior to this positive result, this asymptomatic staff member had tested positive for COVID-19, had quarantined for two weeks, and had received a negative test. CONCLUSION: Though COVID-19 is currently widespread in the United States, this study shows that health care personnel working in New York City at the Columbia University Irving Medical Center have a low chance of encountering viral RNA on surfaces they are in close contact with during daily life.


Asunto(s)
COVID-19 , ARN Viral , Estudios Transversales , Humanos , Ciudad de Nueva York/epidemiología , Pandemias , SARS-CoV-2
8.
Ther Adv Ophthalmol ; 13: 25158414211022882, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34263135

RESUMEN

Hemoglobinopathies are genetic disorders that lead to abnormal structure of the hemoglobin molecule. Sickle cell disease, the most common inherited blood disorder, is characterized by defective oxygen transport. Almost every part of the eye can be affected by sickle cell disease; however, proliferative sickle cell retinopathy is the primary cause of vision loss, either from vitreous hemorrhage or retinal detachment. Here we review the various manifestations of hemoglobinopathies on the eyes of children and adolescents, with a specific focus on sickle cell disease and its different phenotypes. Newer, more sensitive ophthalmological imaging modalities, including ultra-widefield fluorescein angiography, spectral-domain optical coherence tomography, and optical coherence tomography angiography, are available. These sensitive modalities allow for a more thorough examination of the retinal periphery where sickle cell retinopathy is often present. Utilization of such modalities will help with the early detection of the disease in children, which provide a better understanding of the pathogenesis of the disease and guide future screening and treatment regimens.

9.
Am J Ophthalmol Case Rep ; 23: 101128, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34169179

RESUMEN

PURPOSE: Central retinal vein occlusions (CRVO) are relatively common; however, they are rare in young, otherwise healthy individuals. We report a case of CRVO associated with creatine supplementation and dehydration in a 25-year-old man. OBSERVATIONS: A 25-year-old man developed a non-ischemic CRVO in the right eye. Comprehensive thrombophilia screening was unrevealing. Further questioning revealed that the patient was an avid weightlifter and had been taking creatine as a nutrition supplement daily for the past 5 years at a higher than recommended dose. At the time of CRVO onset, he was also restricting water intake in order to lose weight. CONCLUSIONS AND IMPORTANCE: We conclude that the CRVO occurred in the context of creatine use and water restriction, leading to increased risk for thrombosis. Given the increased popularity for nutritional supplements to enhance fitness, it is important for individuals to recognize the association between CRVO, creatine supplementation, and hydration status.

10.
Am J Ophthalmol Case Rep ; 22: 101082, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33948521

RESUMEN

PURPOSE: To describe findings of multimodal imaging in non-proliferative and proliferative stages of MacTel 2 in a pediatric patient, and results of aflibercept use for treating neovascularization secondary to MacTel 2. METHODS: Retrospective case report. RESULTS: An 11-year-old girl with no history of systemic disease. BCVA was 20/200 and 20/40 in the right and left eyes, respectively. FFA, SS-OCT and SS-OCTA revealed proliferative and non-proliferative stages of MacTel 2 in the right and left eyes, respectively. Intravitreal aflibercept (2mg/0.05mL) was started (PRN) in the right eye. The patient received 5 injections that led to involution of macular neovascularization and improvement of BCVA by 5 lines. BCVA in the left eye remained stable. CONCLUSION: MacTel 2 can develop in an earlier age than previously reported. SS-OCTA is an effective alternative to conventional imaging in diagnosis and follow-up especially in pediatric patients. Intravitreal aflibercept is effective in treating proliferative MacTel 2.

11.
Clin Ophthalmol ; 15: 825-834, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33658758

RESUMEN

PURPOSE: To assess the efficacy of customized slab segmentation in eliminating projection artifacts in swept-source optical coherence tomography angiography (SS-OCTA) images of Best vitelliform macular dystrophy (BVMD). METHODS: Prospective case series including different stages of BVMD. We analyzed SS-OCTA images for flow signals in the outer retina and coregistered B-scan images for distortion of the segmentation slabs defining the outer retina. We applied a customized method for slab realignment whenever BVMD lesions produced distortion of the slabs. Afterward, we checked the images to determine whether the previously noted flow signal had persisted or disappeared, described as "true flow" or "pseudoflow", respectively. Categorical variables were analyzed with X2 or Fisher's exact tests, while quantitative variables were analyzed with independent t-test at p<0.05. RESULTS: The study included 39 eyes of 22 patients. We detected BVMD patterns I (dome-shaped hyperreflective lesion without neurosensory retinal detachment), II (knob-like hyperreflective lesion with localized neurosensory retinal detachment), and III (heterogeneous scattered hyperreflective material) in 49%, 23%, and 28% of eyes, respectively. Pseudoflow was evident mostly in eyes with pattern II lesions, presence of flow signal within BVMD lesions, and lesions whose height represented >80% of the retinal thickness (p<0.001). CONCLUSION: Customized slab segmentation is effective in eliminating projection artifact in SS-OCTA images of BVMD. SUMMARY: Projection artifact is a significant confounding factor in emerging SS-OCTA technology through production of pseudoflow signals that can lead to misinterpretation of images of BVMD lesions. The present study proposes a customized method for correction of segmentation errors to eliminate projection artifacts in SS-OCTA images of BVMD patients.

12.
Int Ophthalmol ; 41(4): 1437-1443, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33475906

RESUMEN

BACKGROUND: The aims of this study were to provide real-life data about the effect of COVID-19 pandemic on the practice of anti-VEGF injections and to evaluate the safety of the modifications in the injection protocol imposed during the ongoing pandemic on the anatomical and functional outcome of patients. METHODS: All patients attending Tanta University hospital for receiving intravitreal anti-VEGF injections were screened. Patients who were previously deferred according to a modified protocol implemented in the hospital in response to the pandemic or who demonstrated deviation from it were included for further analysis. RESULTS: During the audit period, 83 patients attending for anti-VEGF injections were screened, of whom 40 met the abovementioned criteria and were included for analysis. In the deferred subgroup (11 eyes), predeferral mean values of logMAR best corrected visual acuity (BCVA) and central retinal subfield thickness (CST) were 1 ± 0.23 and 444.57 ± 200.1 µm, respectively. There was no significant change when the patients returned for their deferred injections, with the mean BCVA and CST values being 0.8 ± 0.22 and 413.71 ± 237.7 µm, respectively (p = 0.27 and p = 0.12). Moreover, 29 patients encountered a disturbed injection schedule, particularly skipping their injection appointments due to infection fear as found in 18 patients. CONCLUSION: The COVID-19 pandemic has imposed pressing challenges in maintaining essential health care while ensuring the prevention of spread of infection. Although the modified injection protocol confirmed to be safe for patients, the pandemic caused deflection from the optimum practice in the form of successive skipping of appointments and delays in the processing of patient injection schedules.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Bevacizumab/administración & dosificación , COVID-19 , Retinopatía Diabética , Inyecciones Intravítreas , Edema Macular , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Auditoría Clínica , Retinopatía Diabética/tratamiento farmacológico , Hospitales , Humanos , Edema Macular/tratamiento farmacológico , Pandemias , Resultado del Tratamiento , Agudeza Visual
13.
Int J Mol Sci ; 21(11)2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32517051

RESUMEN

: Melanoma is a type of skin cancer that originates in the pigment-producing cells of the body known as melanocytes. Most genetic aberrations in melanoma result in hyperactivation of the mitogen activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways. We and others have shown that a specific protein synthesis pathway known as the MNK1/2-eIF4E axis is often dysregulated in cancer. The MNK1/2-eIF4E axis is a point of convergence for these signaling pathways that are commonly constitutively activated in melanoma. In this review we consider the functional implications of aberrant mRNA translation in melanoma and other malignancies. Moreover, we discuss the consequences of inhibiting the MNK1/2-eIF4E axis on the tumor and tumor-associated cells, and we provide important avenues for the utilization of this treatment modality in combination with other targeted and immune-based therapies. The past decade has seen the increased development of selective inhibitors to block the action of the MNK1/2-eIF4E pathway, which are predicted to be an effective therapy regardless of the melanoma subtype (e.g., cutaneous, acral, and mucosal).


Asunto(s)
Factor 4E Eucariótico de Iniciación/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Melanoma/etiología , Melanoma/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Animales , Biomarcadores de Tumor , Terapia Combinada , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Humanos , Inmunoterapia , Melanoma/tratamiento farmacológico , Melanoma/patología , Técnicas de Diagnóstico Molecular , Terapia Molecular Dirigida , Transducción de Señal/efectos de los fármacos , Investigación Biomédica Traslacional , Resultado del Tratamiento
14.
J Am Coll Surg ; 230(4): 373-379, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32035182

RESUMEN

BACKGROUND: Flow cytometric crossmatching is currently the method of choice for most transplantation programs before kidney transplantation. In July of 2017, our program implemented the virtual crossmatch, without a prospective physical crossmatch, for the majority of patients in the setting of a new kidney allocation system implemented by the United Network for Organ Sharing. STUDY DESIGN: A retrospective review was conducted to determine whether virtual crossmatching could reduce cold ischemia time (CIT). Secondary outcomes included the incidence of delayed graft function and 1-year patient and allograft failure. RESULTS: A total of 825 patients received a kidney transplant between December 1, 2014 and July 1, 2018; 505 were in the pre-implementation group and 227 were in the post-implementation group. The CIT decreased between the pre-implementation era to post implementation era from 16.67 ± 8.7 hours to 14.5 ± 8.2 hours (p = 0.002). On univariate analysis, delayed graft function (DGF) rates were similar between the 2 eras (19% vs 17%; p = 0.415), despite having more donations after cardiac death and higher Kidney Donor Profile Index donors in the post-implementation era. There was no difference in biopsy-proven acute rejection (n = 28 [5.6%] vs n = 8 [3.5%]; p = 0.226), 1-year graft loss (4% vs 3%; p = 0.304), or patient death (2% vs 1%; p = 0.567) rate between groups. On multivariable modeling for mean CIT and incidence of DGF, patients receiving transplants in the post-implementation era had an adjusted reduction in CIT of an estimated 2.35 hours (95% CI, 1.15 to 3.55; p < 0.001). Patients in the post-implementation era also had 26% lower odds of DGF developing (odds ratio 0.74; 95% CI, 0.48 to 1.14; p = 0.170), after adjusting for covariates. CONCLUSIONS: Kidney transplantation can be safely performed with virtual crossmatching, without a prospective physical crossmatch with improved CIT and potentially reduced DGF rate without increased risk of rejection.


Asunto(s)
Selección de Donante/métodos , Prueba de Histocompatibilidad/métodos , Trasplante de Riñón , Selección de Paciente , Obtención de Tejidos y Órganos/métodos , Adulto , Anciano , Algoritmos , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Interfaz Usuario-Computador
15.
J Clin Apher ; 33(6): 673-677, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30321467

RESUMEN

BACKGROUND: Angiotensin II type-1 receptor antibody (AT1RAb) has been reported to cause antibody mediated rejection (AMR) in kidney transplant recipients possibly by contraction of renal arteries. We here report 2 kidney transplant recipients with elevated AT1RAbs and negative HLA donor specific antibodies (DSA) and anti-major histocompatibility complex class I chain-related gene A (MICA) Abs who received therapeutic plasma exchange (TPE) treatment followed by IVIG. CASE 1: Thirty-eight-year-old patient received second kidney transplant for end stage renal disease (ESRD) with chronic rejection. Three years post-transplant, she developed AMR with AT1RAb level >40 U/mL. She received 5 TPE and AT1RAb decreased by 20%, and biopsy showed improvement of AMR. She received another 3 TPE and AT1RAb decreased by 60%. Her creatinine (Cr) was stabilized at around 1.4 mg/dL. CASE 2: Twenty-four-year-old patient received kidney transplant for ESRD with unclear etiology. Two weeks post-transplant, her Cr rose with AT1RAb level at 18 U/mL and biopsy showed possible AMR. She received 6 TPE treatments and AT1RAb decreased by 55% and biopsy showed improvement of AMR. She received weekly TPE for subsequently rising AT1RAb but TPE was discontinued because of unsuccessful decrease of AT1RAb. Her Cr was stabilized at around 1.7 mL/dL. CONCLUSION: We reported 2 patients who received TPE treatments to decrease AT1RAbs. A course of TPE treatment successfully decreased AT1RAb. Histological improvement was observed quickly and Cr was also stabilized following the TPE treatment. Further study is necessary to determine the optimal use of TPE in renal transplant recipients with AT1RAbs.


Asunto(s)
Anticuerpos/sangre , Trasplante de Riñón/efectos adversos , Intercambio Plasmático/métodos , Receptor de Angiotensina Tipo 1/inmunología , Adulto , Creatinina/sangre , Femenino , Rechazo de Injerto/prevención & control , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Adulto Joven
16.
Sci Total Environ ; 627: 812-821, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29426206

RESUMEN

The Gulf of Tadjoura is located in the Horn of Africa and is widely recognized as an important site where the zooplanktivorous whale sharks seasonally aggregate from October to February. The surface zooplankton community (0-3m) was weekly sampled from November 2016 to February 2017 in two sites during the whale shark aggregation period. A total of 12 phyla were identified. Copepoda represented the most abundant and diverse group with 29 different genera, and contributed with an average of 82% of the mean zooplankton density of approximately 6600indm-3. During the sampling period, copepods were dominated numerically by Calanoida (3600indm-3), followed by Poicilostomatatoida (1300indm-3). Within the copepods, Paracalanidae, Calanidae, Oncaeidae and Miraciidae were the most common families. The temporal trend in zooplankton biomass at both stations revealed the highest peak in December (41.3±36.4mgm-3), and the lowest in February (6.6±3.3mgm-3). As no information is available on the occurrence of legacy contaminants use and release in this area, analysis revealed the consistent presence of both DDT and PCB residues in zooplankton samples in the Gulf of Tadjoura. Total PCB ranged from approximately 110 to 637ngg-1 d.w., while total DDT from 21 to 80ngg-1 d.w. The proportion of primary DDT in the total residue was higher than DDE and DDD, which strongly suggests that the area might actually be subjected to DDT inputs of the parent compound.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad , Zooplancton/clasificación , África , Animales , Biodiversidad , Copépodos , Djibouti , Agua de Mar/química , Tiburones , Contaminantes Químicos del Agua/análisis , Zooplancton/crecimiento & desarrollo
17.
Exp Clin Transplant ; 15(1): 47-55, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27267614

RESUMEN

OBJECIVES: Elevated panel reactive antibody levels have been traditionally associated with increased acute rejection rate and decreased long-term graft survival after kidney transplant. In this study, our objective was to determine patient and allograft outcomes in sensitized kidney transplant recipients with advanced HLA antibody detection and stringent protein sequence epitope analyses. MATERIALS AND METHODS: This was a subanalysis of a prospective, risk-stratified randomized controlled trial that compared interleukin 2 receptor antagonist to rabbit antithymocyte globulin induction in 200 kidney transplant recipients, examining outcomes based on panel reactive antibody levels of < 20% (low) versus ≥ 20% (high, sensitized). The study was conducted between February 2009 and July 2011. All patients underwent solid-phase single antigen bead assays to detect HLA antibodies and stringent HLA epitope analyses with protein sequence alignment for virtual crossmatching. Delayed graft function, acute rejection rates, and graft loss were the main outcomes measured. RESULTS: Both the low (134 patients) and high (66 patients) panel reactive antibody level cohorts had equivalent induction and maintenance immunosuppression. Patients in the high-level group were more likely to be female (P < .001), African American (P < .001), and received a kidney from a deceased donor (P = .004). Acute rejection rates were similar between the low (rate of 8%) and high (rate of 9%) panel reactive antibody groups (P = .783). Delayed graft function, borderline rejection, graft loss, and death were not different between groups. Multivariate analyses demonstrated delayed graft function to be the strongest predictor of acute rejection (odds ratio, 5.7; P = .005); panel reactive antibody level, as a continuous variable, had no significant correlation with acute rejection (C statistic, 0.48; P = .771). CONCLUSIONS: Appropriate biologic matching with single antigen bead assays and stringent epitope analyses provided excellent outcomes in sensitized patients regardless of the induction therapy choice.


Asunto(s)
Epítopos , Antígenos HLA/inmunología , Prueba de Histocompatibilidad/métodos , Histocompatibilidad , Isoanticuerpos/sangre , Trasplante de Riñón , Adulto , Anciano , Aloinjertos , Suero Antilinfocítico/uso terapéutico , Área Bajo la Curva , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Funcionamiento Retardado del Injerto/etiología , Quimioterapia Combinada , Femenino , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Inmunosupresores/uso terapéutico , Estimación de Kaplan-Meier , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/mortalidad , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Receptores de Interleucina-2/antagonistas & inhibidores , Receptores de Interleucina-2/inmunología , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
18.
PLoS One ; 9(9): e107530, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25202904

RESUMEN

The transcription factor FOXO3 is a well-established tumor suppressor whose activity, stability, and localization are regulated by phosphorylation and acetylation. Previous data by our laboratory demonstrated amplified thromboxane-A2 signaling was associated with poor prognoses in bladder cancer patients and overexpression of the thromboxane-A2 isoform-ß receptor (TPß), but not TPα, induced malignant transformation of immortalized bladder cells in vivo. Here, we describe a mechanism of TP mediated modulation of FOXO3 activity and localization by phosphorylation and deacetylation in a bladder cancer cell model. In vitro gain and loss of function studies performed in non-transformed cell lines, UROsta and SV-HUC, revealed knockdown of FOXO3 expression by shRNA increased cell migration and invasion, while exogenously overexpressing TPß raised basal phosphorylated (p)FOXO3-S294 levels. Conversely, overexpression of ERK-resistant, mutant FOXO3 reduced increases in UMUC3 cell migration and invasion, including that mediated by TP agonist (U46619). Additionally, stimulation of UMUC3 cells with U46619 increased pFOXO3-S294 expression, which could be attenuated by treatment with a TP antagonist (PTXA2) or ERK inhibitor (U0126). Initially U46619 caused nuclear accumulation of pFOXO3-S294; however, prolonged stimulation increased FOXO3 cytoplasmic localization. U46619 stimulation decreased overall FOXO3 transcriptional activity, but was associated with increased expression of its pro-survival target, manganese superoxide dismutase. The data also shows that TP stimulation increased the expression of the histone deacetylase, SIRT1, and corresponded with decreased acetylated-FOXO3. Collectively, the data suggest a role for TP signaling in the regulation of FOXO3 activity, mediated in part through phosphorylation and deacetylation.


Asunto(s)
Factores de Transcripción Forkhead/genética , Receptores de Tromboxano A2 y Prostaglandina H2/genética , Proteínas Supresoras de Tumor/genética , Neoplasias Urológicas/genética , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Butadienos/farmacología , Línea Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Citoplasma/efectos de los fármacos , Citoplasma/genética , Proteína Forkhead Box O3 , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Nitrilos/farmacología , Fosforilación/efectos de los fármacos , Fosforilación/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Sirtuina 1/genética , Superóxido Dismutasa/genética , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética
19.
J Heart Lung Transplant ; 33(12): 1282-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25128416

RESUMEN

BACKGROUND: A higher degree of human leukocyte antigen (HLA) matching at the A, B, and DR loci has been associated with improved long-term survival after pediatric heart transplantation in multiple International Society for Heart and Lung Transplantation registry reports. The aim of this study was to investigate the association of HLA matching at the C and DQ loci with pediatric graft survival. METHODS: The United Network of Organ Sharing database was queried for isolated heart transplants that occurred from 1988 to 2012 with a recipient age of 17 or younger and at least 1 postoperative follow-up encounter. When HLA matching at the C or DQ loci were analyzed, only transplants with complete typing of donor and recipient at the respective loci were included. Transplants were divided into patients with at least 1 match at the C locus (C-match) vs no match (C-no), and at least 1 match at the DQ (DQ-match) locus vs no match (DQ-no). Primary outcome was graft loss. Univariate analysis was performed with the log-rank test. Cox regression analysis was performed with the following patient factors included in the model: recipient age, ischemic time; recipient on ventilator, extracorporeal membrane oxygenation, ventricular assist device, or inotropes at transplant; recipient serum bilirubin and creatinine closest to transplant, ratio of donor weight to recipient weight, underlying cardiac diagnosis, crossmatch results, transplant year, and HLA matching at the A, B, and DR loci. RESULTS: Complete typing at the C locus occurred in 2,429 of 4,731 transplants (51%), and complete typing at the DQ locus occurred in 3,498 of 4,731 transplants (74%). Patient factors were similar in C-match and C-no, except for year of transplant (median year, 2007 [interquartile range, 1997-2010] vs year 2005 [interquartile range, 1996-2009], respectively; p = 0.03) and the degree of HLA matching at the A, B, and DR loci (high level of HLA matching in 11.9% vs 3%, respectively; p < 0.01). Matching at the C locus was not associated with a decreased risk of graft loss (median graft survival: 13.1 years [95% confidence interval {CI}, 11.5-14.8] in C-no vs 15.1 years [95% CI, 13.5-16.6) in C-match, p = 0.44 log-rank; hazard ratio, 0.93; 95% CI, 0.76-1.15; p = 0.52). DQ-match did not differ from DQ-no in any of the analyzed patient factors, except DQ-match was more likely to have high degree of matching at the A, B, and DR loci vs DQ-no (9.8% vs 3.2%, p < 0.01). Matching at the DQ locus was not associated with decreased risk of graft loss (median graft survival: DQ-no, 13.1 years [95% CI, 11.7-14.6) vs DQ-match, 13.0 years [95% CI, 11.4-14.6], p = 0.80, log-rank; hazard ratio, 0.95; 95% CI, 0.81-1.1; p = 0.51. CONCLUSIONS: Complete typing at the C locus of both donor and recipient occurs less often then typing at the DQ locus. A higher degree of donor-recipient HLA matching at the C locus or the DQ locus appears not to confer any graft survival advantage.


Asunto(s)
Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Antígenos HLA-C/inmunología , Antígenos HLA-DQ/inmunología , Trasplante de Corazón , Prueba de Histocompatibilidad/métodos , Adolescente , Niño , Preescolar , Rechazo de Injerto/epidemiología , Humanos , Incidencia , Lactante , Estimación de Kaplan-Meier , Análisis de Regresión , Estudios Retrospectivos , Donantes de Tejidos , Obtención de Tejidos y Órganos/métodos , Receptores de Trasplantes
20.
Circ Heart Fail ; 7(4): 605-11, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24833649

RESUMEN

BACKGROUND: The effect of donor-recipient human leukocyte antigen (HLA) matching on outcomes remains relatively unexplored in pediatric patients. The objective of this study was to investigate the effects of donor-recipient HLA matching on graft survival in pediatric heart transplantation. METHODS AND RESULTS: The UNOS (United Network for Organ Sharing) database was queried for heart transplants occurring between October 31, 1987, and December 31, 2012, in a recipient aged ≤17 years with ≥1 postoperative follow-up visit. Retransplants were excluded. Transplants were divided into 3 donor-recipient matching groups: no HLA matches (HLA-no), 1 or 2 HLA matches (HLA-low), and 3 to 6 HLA matches (HLA-high). Primary outcome was graft loss. Four thousand four hundred seventy-one heart transplants met the study inclusion criteria. High degree of donor-recipient HLA matching occurred infrequently: HLA-high (n=269; 6%) versus HLA-low (n=2683; 60%) versus HLA-no (n=1495; 34%). There were no differences between HLA matching groups in the frequency of coronary vasculopathy (P=0.19) or rejection in the first post-transplant year (P=0.76). Improved graft survival was associated with a greater degree of HLA donor-recipient matching: HLA-high median survival, 17.1 (95% confidence interval, 14.0-20.2) years; HLA-low median survival, 14.2 (13.1-15.4) years; and HLA-no median survival, 12.1 (10.9-13.3 years) years; P<0.01, log-rank test. In Cox-regression analysis, HLA matching was independently associated with decreased graft loss: HLA-low versus HLA-no hazard ratio, 0.86 (95% confidence interval, 0.74-0.99), P=0.04; HLA-high versus HLA-no, 0.62 (95% confidence interval, 0.43-0.90), P<0.01. CONCLUSIONS: Decreased graft loss in pediatric heart transplantation was associated with a higher degree of donor-recipient HLA matching, although a difference in the frequency of early rejection or development of coronary artery vasculopathy was not seen.


Asunto(s)
Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Corazón , Donantes de Tejidos , Obtención de Tejidos y Órganos , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Sistema de Registros , Estudios Retrospectivos , South Carolina/epidemiología , Tasa de Supervivencia/tendencias
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