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1.
JACC Case Rep ; 29(3): 102196, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38361566

RESUMEN

Spontaneous coronary artery dissection occurs predominantly in women and is associated with fibromuscular dysplasia. We illustrate a rare case of sudden coronary death as a result of cardiac rupture from spontaneous coronary artery dissection in a 54-year-old man without fibromuscular dysplasia. Cardiac rupture has been previously reported in 6 cases, mostly in women.

2.
Acta Neuropathol ; 147(1): 4, 2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-38133681

RESUMEN

LATE-NC, the neuropathologic changes of limbic-predominant age-related TAR DNA-binding protein 43 kDa (TDP-43) encephalopathy are frequently associated with Alzheimer's disease (AD) and cognitive impairment in older adults. The association of TDP-43 proteinopathy with AD neuropathologic changes (ADNC) and its impact on specific cognitive domains are not fully understood and whether loss of TDP-43 function occurs early in the aging brain remains unknown. Here, using a large set of autopsies from the Baltimore Longitudinal Study of Aging (BLSA) and another younger cohort, we were able to study brains from subjects 21-109 years of age. Examination of these brains show that loss of TDP-43 splicing repression, as judged by TDP-43 nuclear clearance and expression of a cryptic exon in HDGFL2, first occurs during the 6th decade, preceding by a decade the appearance of TDP-43+ neuronal cytoplasmic inclusions (NCIs). We corroborated this observation using a monoclonal antibody to demonstrate a cryptic exon-encoded neoepitope within HDGFL2 in neurons exhibiting nuclear clearance of TDP-43. TDP-43 nuclear clearance is associated with increased burden of tau pathology. Age at death, female sex, high CERAD neuritic plaque score, and high Braak neurofibrillary stage significantly increase the odds of LATE-NC. Faster rates of cognitive decline on verbal memory (California Verbal Learning Test immediate recall), visuospatial ability (Card Rotations Test), mental status (MMSE) and semantic fluency (Category Fluency Test) were associated with LATE-NC. Notably, the effects of LATE-NC on verbal memory and visuospatial ability are independent of ADNC. However, the effects of TDP-43 nuclear clearance in absence of NCI on the longitudinal trajectories and levels of cognitive measures are not significant. These results establish that loss of TDP-43 splicing repression is an early event occurring in the aging population during the development of TDP-43 proteinopathy and is associated with increased tau pathology. Furthermore, LATE-NC correlates with high levels of ADNC but also has an impact on specific memory and visuospatial functions in aging that is independent of AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Proteinopatías TDP-43 , Humanos , Femenino , Anciano , Enfermedad de Alzheimer/patología , Estudios Longitudinales , Proteinopatías TDP-43/patología , Envejecimiento/genética , Disfunción Cognitiva/genética , Disfunción Cognitiva/complicaciones , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo
3.
JAMA Neurol ; 79(6): 544-553, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35404378

RESUMEN

Importance: Loss of smell is an early and common presentation of COVID-19 infection. Although it has been speculated that viral infection of olfactory neurons may be the culprit, it is unclear whether viral infection causes injuries in the olfactory bulb region. Objective: To characterize the olfactory pathology associated with COVID-19 infection in a postmortem study. Design, Setting, and Participants: This multicenter postmortem cohort study was conducted from April 7, 2020, to September 11, 2021. Deceased patients with COVID-19 and control individuals were included in the cohort. One infant with congenital anomalies was excluded. Olfactory bulb and tract tissue was collected from deceased patients with COVID-19 and appropriate controls. Histopathology, electron microscopy, droplet digital polymerase chain reaction, and immunofluorescence/immunohistochemistry studies were performed. Data analysis was conducted from February 7 to October 19, 2021. Main Outcomes and Measures: (1) Severity of degeneration, (2) losses of olfactory axons, and (3) severity of microvasculopathy in olfactory tissue. Results: Olfactory tissue from 23 deceased patients with COVID-19 (median [IQR] age, 62 [49-69] years; 14 men [60.9%]) and 14 control individuals (median [IQR] age, 53.5 [33.25-65] years; 7 men [50%]) was included in the analysis. The mean (SD) axon pathology score (range, 1-3) was 1.921 (0.569) in patients with COVID-19 and 1.198 (0.208) in controls (P < .001), whereas axon density was 2.973 (0.963) × 104/mm2 in patients with COVID-19 and 3.867 (0.670) × 104/mm2 in controls (P = .002). Concomitant endothelial injury of the microvasculature was also noted in olfactory tissue. The mean (SD) microvasculopathy score (range, 1-3) was 1.907 (0.490) in patients with COVID-19 and 1.405 (0.233) in control individuals (P < .001). Both the axon and microvascular pathology was worse in patients with COVID-19 with smell alterations than those with intact smell (mean [SD] axon pathology score, 2.260 [0.457] vs 1.63 [0.426]; P = .002; mean [SD] microvasculopathy score, 2.154 [0.528] vs 1.694 [0.329]; P = .02) but was not associated with clinical severity, timing of infection, or presence of virus. Conclusions and Relevance: This study found that COVID-19 infection is associated with axon injuries and microvasculopathy in olfactory tissue. The striking axonal pathology in some cases indicates that olfactory dysfunction in COVID-19 infection may be severe and permanent.


Asunto(s)
COVID-19 , Trastornos del Olfato , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Olfato/etiología , SARS-CoV-2 , Olfato/fisiología
4.
Front Pharmacol ; 13: 817237, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237167

RESUMEN

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human stomach leading to the development of chronic gastritis, peptic ulcers and gastric adenocarcinoma. A combination of host, environment and bacterial virulence factors contribute to disease development. The H. pylori TNFα inducing protein (Tipɑ) is a virulence factor shown to induce multiple pro-inflammatory cytokines in addition to TNFα in vitro. The goal of the present study was to elucidate the role of Tipα in promoting inflammation in vivo and to identify the molecular pathways associated with Tipα associated virulence. Mice were infected with wild-type Sydney strain (SS1) or a tipα mutant (Δtipα) for 1 month and 4 months. We also completed a second 4 months infection including a 1:1 SS1 to Δtipα co-infected group in addition to SS1 and Δtipα infected groups. The expression of TNFα, and KC were significantly higher in the SS1 infected group compared to both uninfected control (naïve) and Δtipα groups. Mice infected with Tipα expressing SS1 induced more severe histological gastritis and developed hyperplasia compared to Δtipα infected mice. Microarray analysis of gastric epithelial cells co-cultured with recombinant Tipα (rTipα) demonstrates up-regulation of the NFκB pathway. This data suggest Tipα plays an important role in H. pylori induced inflammation.

5.
bioRxiv ; 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-35132414

RESUMEN

The neurotropism of SARS-CoV-2 and the phenotypes of infected neurons are still in debate. Long COVID manifests with "brain diseases" and the cause of these brain dysfunction is mysterious. Here, we analyze 34 age- and underlying disease-matched COVID-19 or non-COVID-19 human brains. SARS-CoV-2 RNA, nucleocapsid, and spike proteins are present in neurons of the cognitive centers of all COVID-19 patients, with its non-structural protein NSF2 detected in adult cases but not in the infant case, indicating viral replications in mature neurons. In adult COVID-19 patients without underlying neurodegeneration, SARS-CoV-2 infection triggers Aß and p-tau deposition, degenerating neurons, microglia activation, and increased cytokine, in some cases with Aß plaques and p-tau pretangles. The number of SARS-CoV-2 + cells is higher in patients with neurodegenerative diseases than in those without such conditions. SARS-CoV-2 further activates microglia and induces Aß and p-tau deposits in non-Alzheimer's neurodegenerative disease patients. SARS-CoV-2 infects mature neurons derived from inducible pluripotent stem cells from healthy and Alzheimer's disease (AD) individuals through its receptor ACE2 and facilitator neuropilin-1. SARS-CoV-2 triggers AD-like gene programs in healthy neurons and exacerbates AD neuropathology. An AD infectious etiology gene signature is identified through SARS-CoV-2 infection and silencing the top three downregulated genes in human primary neurons recapitulates the neurodegenerative phenotypes of SARS-CoV-2. Thus, our data suggest that SARS-CoV-2 invades the brain and activates an AD-like program.

6.
BMJ Open Respir Res ; 8(1)2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34521649

RESUMEN

BACKGROUND: NHS England recommends non-invasive continuous positive airway pressure (CPAP) as a possible treatment for type 1 respiratory failure associated with COVID-19 pneumonitis, either to avoid intubation or as a ceiling of care. However, data assessing this strategy are sparse, especially for the use of CPAP as a ceiling of care, and particularly when delivered outside of a traditional critical care environment. We describe a cohort of patients from Liverpool, UK, who received CPAP on a dedicated respiratory surge unit at the start of the second wave of the COVID-19 pandemic in UK. METHODS: Retrospective cohort analysis of consecutive patients receiving CPAP for the treatment of respiratory failure secondary to COVID-19 on the respiratory surge unit at the Royal Liverpool Hospital, Liverpool, UK from 21 September until 30 November 2020. RESULTS: 88 patients were included in the analysis. 56/88 (64%) were deemed suitable for escalation to invasive mechanical ventilation (IMV) and received CPAP as a trial; 32/88 (36%) received CPAP as a ceiling of care. Median age was 63 years (IQR: 56-74) and 58/88 (66%) were men. Median SpO2/FiO2 immediately prior to CPAP initiation was 95 (92-152). Among patients for escalation to IMV, the median time on CPAP was 6 days (IQR 4-7) and survival at day 30 was 84% (47/56) with 14/56 (25%) escalated to IMV. Of those patients for whom CPAP was ceiling of care, the median duration of CPAP was 9 days (IQR 7-11) and 18/32 (56%) survived to day 30. Pulmonary barotrauma occurred in 9% of the cohort. There were no associations found on multivariant analysis that were associated with all-cause 30-day mortality. CONCLUSIONS: With adequate planning and resource redistribution, CPAP may be delivered effectively outside of a traditional critical care setting for the treatment of respiratory failure due to COVID-19. Clinicians delivering CPAP to patients with COVID-19 pneumonitis should be alert to the dangers of pulmonary barotrauma. Among patients who are for escalation of care, the use of CPAP may avoid the need for IMV in some patients. Our data support the NHS England recommendation to consider CPAP as a ceiling of care.


Asunto(s)
COVID-19 , Presión de las Vías Aéreas Positiva Contínua , Anciano , COVID-19/terapia , Cuidados Críticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Estudios Retrospectivos , Reino Unido/epidemiología
7.
Clin Med Insights Oncol ; 15: 11795549211012672, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34158803

RESUMEN

BACKGROUND: The death rate (the number of deaths per 100 000 people per year) of colorectal cancer (CRC) has been dropping since 1980 due to increased screening, lifestyle-related risk factors, and improved treatment options; however, CRC is the third leading cause of cancer-related deaths in men and women in the United States. Therefore, successful therapy for CRC is an unmet clinical need. This study aimed to investigate the impacts of andrographolide (AGP) and melatonin (MLT) on CRC and the underlying mechanism. METHODS: To investigate AGP and MLT anticancer effects, a series of metastatic colon cancer cell lines (T84, Colo 205, HT-29, and DLD-1) were selected. In addition, a metastatic patient-derived organoid model (PDOD) was used to monitor the anticancer effects of AGP and MLT. A series of bioassays including 3D organoid cell culture, MTT, colony formation, western blotting, immunofluorescence, and quantitative polymerase chain reaction (qPCR) were performed. RESULTS: The dual therapy significantly promotes CRC cell death, as compared with the normal cells. It also limits CRC colony formation and disrupts the PDOD membrane integrity along with decreased Ki-67 expression. A significantly higher cleaved caspase-3 and the endoplasmic reticulum (ER) stress proteins, IRE-1 and ATF-6 expression, by 48 hours were found. This combinatorial treatment increased reactive oxygen species (ROS) levels. Apoptosis signaling molecules BAX, XBP-1, and CHOP were significantly increased as determined by qPCR. CONCLUSIONS: These findings indicated that AGP and MLT associated ER stress-mediated apoptotic metastatic colorectal cancer (mCRC) cell death through the IRE-1/XBP-1/CHOP signaling pathway. This novel combination could be a potential therapeutic strategy for mCRC cells.

8.
Eur J Pharmacol ; 897: 173919, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33577837

RESUMEN

Colorectal cancer (CRC) mortality has diminished for decades due to new and improved treatment profiles. However, CRC still ranks as the third most diagnosed cancer in the US. Therefore, a new therapeutic approach is needed to overcome colospheroids inhibition and drug resistance. It is well documented that andrographolide (AGP) and melatonin (MLT) have anti-carcinogenic properties. Our goal was to evaluate their synergistic effects on metastatic colon cancer cells (mCRC) and colospheroids. HT-29 and HCT-15 mCRC cells were simultaneously treated with serial dilutions of AGP and MLT for 24, 48 and 72 h. Cell viability was monitored using the MTT assay. The Chou-Talalay method for drug combination is based on the median effect equation, providing a theoretical basis for the combination index and the isobologram equation. This allows quantitative determination of drug interactions using the CompuSyn software, where CI < 1, = 1, and >1 indicates synergistic, additive, and antagonistic effects respectively. Our results demonstrate that AGP and MLT in combination show synergism with CI values of 0.35293 and 0.34152 for HT-29 and HCT-15 respectively and a fractional inhibition of Fa = 0.50-0.90, as shown by the Fa-CI plot and isobologram. The synergism value was validated in colospheroids (HT-29-s and HCT-15-s) based on morphology, viability, and colony formation and in 5-FU drug resistant cell (HT-29R and HCT-116R) viability. The mechanism(s) of decreased cell viability are due to the induction of ER stress proteins and angiogenic inhibition. Our results provide rationale for using AGP in combination with MLT on mCRC.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias del Colon/tratamiento farmacológico , Diterpenos/farmacología , Melatonina/farmacología , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Células HCT116 , Células HT29 , Humanos , Metástasis de la Neoplasia , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Esferoides Celulares
9.
Life Sci ; 255: 117842, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32454157

RESUMEN

The outbreak of COVID-19 caused by 2019-nCov/SARS-CoV-2 has become a pandemic with an urgent need for understanding the mechanisms and identifying a treatment. Viral infections including SARS-CoV are associated with increased levels of reactive oxygen species, disturbances of Ca++ caused by unfolded protein response (UPR) mediated by endoplasmic reticulum (ER) stress and is due to the exploitation of virus's own protein i.e., viroporins into the host cells. Several clinical trials are on-going including testing Remdesivir (anti-viral), Chloroquine and Hydroxychloroquine derivatives (anti-malarial drugs) etc. Unfortunately, each drug has specific limitations. Herein, we review the viral protein involvement to activate ER stress transducers (IRE-1, PERK, ATF-6) and their downstream signals; and evaluate combination therapies for COVID-19 mediated ER stress alterations. Melatonin is an immunoregulator, anti-pyretic, antioxidant, anti-inflammatory and ER stress modulator during viral infections. It enhances protective mechanisms for respiratory tract disorders. Andrographolide, isolated from Andrographis paniculata, has versatile biological activities including immunomodulation and determining SARS-CoV-2 binding site. Considering the properties of both compounds in terms of anti-inflammatory, antioxidant, anti-pyrogenic, anti-viral and ER stress modulation and computational approaches revealing andrographolide docks with the SARS-CoV2 binding site, we predict that this combination therapy may have potential utility against COVID-19.


Asunto(s)
Betacoronavirus/metabolismo , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/virología , Diterpenos/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Melatonina/farmacología , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/virología , Factor de Transcripción Activador 6/metabolismo , Antivirales/farmacología , COVID-19 , Sinergismo Farmacológico , Estrés del Retículo Endoplásmico/fisiología , Endorribonucleasas/metabolismo , Humanos , Terapia Molecular Dirigida , Pandemias , Proteínas Serina-Treonina Quinasas/metabolismo , SARS-CoV-2 , Respuesta de Proteína Desplegada/efectos de los fármacos , eIF-2 Quinasa/metabolismo
10.
Mitochondrial DNA B Resour ; 5(3): 2881-2885, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-33457987

RESUMEN

Hirundo is the most species-rich genus of the passerine swallow family (Hirundinidae) and has a cosmopolitan distribution. Here we report the complete, annotated mitochondrial genomes for 25 individuals from 10 of the 14 extant Hirundo species; these include representatives from four subspecies of the barn swallow, H. rustica. Mitogenomes were conserved in size, ranging from 18,500 to 18,700 base pairs. They all contained 13 protein-coding regions, 22 tRNAs, a control region, and large and small ribosomal subunits. Phylogenetic analysis resolved most of the relationships between the studied species and subspecies which were largely consistent with previously published trees. Several new relationships were observed within the phylogeny that could have only been discovered with the increased amount of genetic material. This study represents the largest Hirundo mitochondrial phylogeny to date, and could serve as a vital tool for other studies focusing on the evolution of the Hirundo genus.

11.
Am J Forensic Med Pathol ; 40(4): 312-317, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31688052

RESUMEN

BACKGROUND: Schizophrenia is a detrimental psychiatric disorder, with an increased mortality from natural and nonnatural causes. METHODS: This study was a retrospective review of autopsy cases of all the individuals with history of schizophrenia investigated by the Office of the Chief Medical Examiner, State of Maryland, for a 5-year period from 2008 to 2012. RESULT: A total of 391 schizophrenia patients were autopsied at the Office of the Chief Medical Examiner because they died suddenly and unexpectedly. Their age ranged from 15 to 100 years with the mean age of 49.5 years. Of the 391 deaths, 191 (48.8%) were white, 185 (47.3%) were African American, and 15 (3.9%) were either Hispanic or Asian. The male and female ratio was 1.5:1. The majority of deaths (64.2%) were caused by natural diseases, 12.0% deaths were accidents, 11.5% deaths were suicides, and 9.7% deaths were homicides. The manner of death remained undetermined in 38 cases (9.7%). Of the 251 natural deaths, 198 cases (78.9%) were owing to cardiovascular diseases. Cause of death was listed as cardiac arrhythmia in 11 cases. This diagnosis of cardiac arrhythmia was made by exclusion based on death scene investigation, review of medical history, complete autopsy, and toxicological tests. Drug intoxication was the second most common cause of death. CONCLUSIONS: The study shows high fatality caused by cardiovascular diseases and drug intoxication among schizophrenia patients, which calls attention of the medical community to closely monitor the high risk factors of sudden death among schizophrenia patients.


Asunto(s)
Muerte Súbita/epidemiología , Esquizofrenia/epidemiología , Accidentes/mortalidad , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/mortalidad , Médicos Forenses , Femenino , Homicidio/estadística & datos numéricos , Humanos , Masculino , Maryland/epidemiología , Persona de Mediana Edad , Intoxicación/mortalidad , Grupos Raciales/estadística & datos numéricos , Estudios Retrospectivos , Distribución por Sexo , Suicidio/estadística & datos numéricos , Adulto Joven
12.
Curr Top Microbiol Immunol ; 421: 1-19, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31123883

RESUMEN

It has been over 30 years since a link was established between H. pylori infection of the gastric mucosa and the development of chronic gastric diseases. Research in rodent models supported by data from human tissue demonstrated that the host immune response to H. pylori is limited by host regulatory T cells. Immunization has been shown to induce a potent Th1- and Th17-mediated immune response capable of eradicating or at least significantly reducing the bacterial load of H. pylori in the stomach in small animal models. These results have not translated well to humans. Clinical trials employing many of the strategies used in rodents for oral immunization including the use of a mucosal adjuvant such as Escherichia coli LT or delivery by attenuated enteric bacteria have failed to limit H. pylori infection and have highlighted the potential toxicity of exotoxin-based mucosal adjuvants. A recent study, however, utilizing a recombinant fusion protein of H. pylori urease and the subunit B of E. coli LT, was performed on over 4000 children. Efficacy of over 70% was demonstrated against naturally acquired infection compared to control volunteers one year post-immunization. Efficacy was reduced, but still above 50% at three years. This study provided new insight into the strategies for developing an improved vaccine for widespread use in countries with high infection rates and where gastric cancer (GC) remains one of the most common causes of death due to cancer.


Asunto(s)
Vacunas Bacterianas/inmunología , Mucosa Gástrica/microbiología , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/patología , Helicobacter pylori/inmunología , Helicobacter pylori/patogenicidad , Animales , Anticuerpos Antibacterianos/inmunología , Vacunas Bacterianas/química , Escherichia coli/inmunología , Mucosa Gástrica/inmunología , Mucosa Gástrica/patología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/prevención & control , Humanos , Inflamación/inmunología , Inflamación/microbiología , Inflamación/patología
13.
Cancers (Basel) ; 11(2)2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30744076

RESUMEN

Metastatic colorectal cancer (mCRC) is characterized by the expression of cellular oncogenes, the loss of tumor suppressor gene function. Therefore, identifying integrated signaling between onco-suppressor genes may facilitate the development of effective therapy for mCRC. To investigate these pathways we utilized cell lines and patient derived organoid models for analysis of gene/protein expression, gene silencing, overexpression, and immunohistochemical analyses. An inverse relationship in expression of oncogenic FoxM1 and tumor suppressor RASSF1A was observed in various stages of CRC. This inverse correlation was also observed in mCRC cells lines (T84, Colo 205) treated with Akt inhibitor. Inhibition of FoxM1 expression in mCRC cells as well as in our ex vivo model resulted in increased RASSF1A expression. Reduced levels of RASSF1A expression were found in normal cells (RWPE-1, HBEpc, MCF10A, EC) stimulated with exogenous VEGF165. Downregulation of FoxM1 also coincided with increased YAP phosphorylation, indicative of tumor suppression. Conversely, downregulation of RASSF1A coincided with FoxM1 overexpression. These studies have identified for the first time an integrated signaling pathway between FoxM1 and RASSF1A in mCRC progression, which may facilitate the development of novel therapeutic options for advanced colon cancer therapy.

14.
Artículo en Inglés | MEDLINE | ID: mdl-30601090

RESUMEN

Ample historical evidence has demonstrated the neurotoxicity of organic Hg. However, several studies have suggested that Se effectively sequesters MeHg. The affinity of Hg is up to ≈106 times higher for Se molecules than for comparable sulfur molecules, most of which are components of brain enzymes. The neurotoxicity of MeHg is associated with its binding to Se and the resultant interference with selenoenzymes (Ralston & Raymond, Global Advances in Selenium Research from Theory to Application, 2016). Therefore, having ample Se reserves is an effective way to mitigate MeHg's toxicity. When the molar ratios of Se to Hg in fish exceed 1.0, ingestion of the fish is unlikely to deplete Se reserves. The goal of this study was to determine the Hg and Se levels, and the Se:Hg molar ratios in freshwater fish from south Louisiana and the implications of those ratios with respect to fish consumption and Hg advisories. Five waterbodies were surveyed (University lake, Calcasieu lake, Toledo Bend, the Atchafalaya River and Henderson Lake). The sampled species included black drum (Pogonias cromis), catfish sp., largemouth bass (Micropterus salmoides) and bluegill (Eupomotis macrochirus). All fish were assayed for total Hg and Se. The average Hg concentration was 0.001 µmol g-1 (0.21 ppm), and all concentrations were below the 1 ppm US FDA action level (from 3.1 × 10-5 to 0.003 µmol g-1). Se concentrations exceeded Hg concentrations in most cases. The average Se concentration was 0.003 µmol g-1 (0.27 ppm), all concentrations were around or less than 1.0 ppm (from 3.7 × 10-4 to 0.017 µmol g-1). Hence, the Se:Hg molar ratios were >1 in all fish except largemouth bass from Henderson Lake. In general, Se was detected in sufficient amounts to sequester Hg, but consumption of largemouth bass from Henderson Lake would pose no risk only if anglers followed the posted Hg advisory. For advisory purposes, perhaps, both Hg and Se levels and Se:Hg molar ratios should be considered. In general, the results indicated that risk assessment will require consideration of both the fish species and body of water, because both can influence Se and Hg concentrations and Se:Hg molar ratios.


Asunto(s)
Monitoreo del Ambiente/métodos , Peces/metabolismo , Mercurio/análisis , Alimentos Marinos/análisis , Selenio/análisis , Contaminantes Químicos del Agua/análisis , Animales , Lagos/química , Louisiana , Músculos/química , Medición de Riesgo , Ríos/química
15.
Perit Dial Int ; 39(1): 42-50, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30257998

RESUMEN

BACKGROUND: Peritoneal dialysis (PD) starters generally have a better outcome compared with hemodialysis (HD) starters, perhaps related to treatment characteristics or case mix. We previously showed that pre- and post-dialysis start clinical parameter trajectories are related to outcomes. The aim of this study was to investigate these trajectories in PD and HD starters. METHODS: This retrospective observational study analyzing data from the Fresenius Medical Care-chronic kidney disease (CKD) Registry from January 2009 to March 2018 examines trends in key clinical parameters through the transition period covering 12 months before to 12 months after dialysis start in 8,088 HD and 1,015 PD starters. RESULTS: Hemodialysis starters differed from PD starters by a significantly greater decline in estimated glomerular filtration rate (eGFR) slope (-0.64 vs -0.45 mL/min/1.73 m2/month) before and higher eGFR (9.85 vs 7.84 mL/min/1.73 m2) at dialysis start. Relatedly, differences in phosphorus (0.07 vs 0.05 mg/dL/month) and hemoglobin (-0.08 vs -0.01 g/dL/month) slopes before the transition to dialysis therapy were observed. After dialysis start, HD starters experienced a greater increase in albumin (0.01 vs 0 g/dL/month) whereas PD starters experienced a decline in serum sodium and higher white blood cell counts compared with HD starters. CONCLUSION: For nephrology practice CKD patients, HD and PD starters appear clinically comparable in the year before dialysis start although HD starters exhibit a more rapid pre-dialytic eGFR decline. Ideally, studies comparing incident HD and PD outcomes should also consider CKD eGFR trajectories. In the first dialysis year, divergence occurs in albumin, white blood cell count, sodium and hemoglobin trends, which may be partly treatment-related.


Asunto(s)
Tasa de Filtración Glomerular/efectos de la radiación , Diálisis Peritoneal/estadística & datos numéricos , Sistema de Registros , Diálisis Renal/estadística & datos numéricos , Insuficiencia Renal Crónica/terapia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Estados Unidos/epidemiología
16.
mSystems ; 3(6)2018.
Artículo en Inglés | MEDLINE | ID: mdl-30505943

RESUMEN

Clinical interventions in the stomach have been linked to fecal microbiota alterations, suggesting a function of the stomach in gastrointestinal (GI) homeostasis. We sought to determine the taxonomic bacterial biogeography of the upper GI tract, including different sites within the human stomach (cardia, corpus, and antrum), adjacent upstream (esophagus) and downstream (duodenum) locations, and luminal contents (aspirate), as well as whole-stomach samples from mice and gerbils. Qualitative and quantitative DNA- and RNA-based taxonomic microbiota analyses were combined to study the relationship of relative and absolute bacterial abundances and transcriptionally active bacterial microbiota components in the stomach of humans and mice. Stomach microbiota compositions resembled those of esophagus and duodenum. However, along the descending GI tract, the relative abundances of specific oropharyngeal commensals decreased (Streptococcus) or increased (Rothia mucilaginosa, Porphyromonas, and Lachnospiraceae). Furthermore, the compositional similarity (weighted UniFrac) between stomach aspirates and esophageal biopsy samples increased with gastric Streptococcus relative abundance. In both human aspirate and mouse stomach samples, Firmicutes were more abundant among transcriptionally active bacteria than Bacteroidetes. The relative abundance of Firmicutes in the stomach was negatively correlated and that of Bacteroidetes was positively correlated with absolute bacterial abundance, suggesting a disproportionate increase of Bacteroidetes over Firmicutes at higher bacterial densities. Human, mouse, and gerbil stomach samples showed similarities at higher taxonomic levels but differences at lower taxonomic levels. Our findings suggest selective enrichment and depletion of specific bacterial taxa in the stomach and Firmicutes being transcriptionally more active than Bacteroidetes that increase in relative abundance with total bacterial load. IMPORTANCE Clinical stomach interventions, such as acid inhibition or bypass surgery, have been linked to fecal microbiota alterations. We demonstrate that the stomach microbiota largely overlaps those of adjacent gastrointestinal locations and identify gradual decreases and increases in the relative abundances of specific bacteria within the stomach, suggesting selective enrichment and depletion. Moreover, similarities between stomach and esophagus samples are proportional to the concentrations of Streptococcus (Firmicutes) in the stomach. The relative abundance of Firmicutes in the stomach, compared to that of Bacteroidetes, is increased in RNA relative to DNA, indicating higher transcriptional activity. Moreover, increased absolute bacterial loads are associated with decreased relative abundance of Firmicutes and higher relative abundance of Bacteroidetes. Our findings characterize the stomach microbiota as influenced by Bacteroidetes influx against a background of transcriptionally more active Firmicutes. Human, mouse, and gerbil stomach microbiotas differ at lower taxonomic levels, which might affect the utility of these model organisms.

17.
Cell Physiol Biochem ; 48(3): 1259-1273, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30045022

RESUMEN

BACKGROUND/AIMS: Silencing of tumor suppressor genes (TSGs) and promotion of angiogenesis are associated with tumor development and metastasis. However, little is known if angiogenic molecules directly control TSGs and vice versa. METHODS: A regulatory link between angiogenesis and down regulation of TSGs was evaluated using an anti-cancer agent, andrographolide (AGP) in cancer cells, mouse xenograft tissues and patient derived organoids through gene/protein expression, gene silencing, and immunohistochemical analyses. RESULTS: AGP treatment demonstrated significant expression of RASSF1A and PTEN TSGs in colon cancer and other cancer cells, mouse tissues and organoids. Depletion of RASSF1A with siRNA limited cyclin D1 and BAX expression. SiRNA depletion of PTEN, upstream regulator of RASSF1A resulted in a 50% reduction in RASSF1A expression. Histopathological analysis of the AGP treated tumor sections showed significant reduction in vessel size, microvascular density and tumor mitotic index suggesting suppression of angiogenesis. This was corroborated by protein analysis demonstrating significant reductions in angiogenesis signaling pathway molecules VEGF165, FOXM1, and pAkt, but significant elevation of the endogenous angiogenesis inhibitor Tsp-2. Treatment of cells with exogenous VEGF prevented the suppression of angiogenesis signaling by AGP, resulting in sustained expression of pAkt, an upstream down-regulator of RASSF1A. RASSF1A expression remained low in VEGF treated cells despite the addition of AGP. CONCLUSION: Our results demonstrate for the first time that AGP induces RASSF1A expression in colon cancer cells and is dependent on angiogenesis signaling events. Therefore, our research may facilitate novel therapeutic options for advanced colon cancer therapy.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Diterpenos/farmacología , Neovascularización Patológica/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Supresoras de Tumor/genética , Regulación hacia Arriba/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Diterpenos/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología
18.
Cogn Sci ; 42(4): 1265-1296, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29687462

RESUMEN

We report three experiments investigating whether people's judgments about causal relationships are sensitive to the robustness or stability of such relationships across a range of background circumstances. In Experiment 1, we demonstrate that people are more willing to endorse causal and explanatory claims based on stable (as opposed to unstable) relationships, even when the overall causal strength of the relationship is held constant. In Experiment 2, we show that this effect is not driven by a causal generalization's actual scope of application. In Experiment 3, we offer evidence that stable causal relationships may be seen as better guides to action. Collectively, these experiments document a previously underappreciated factor that shapes people's causal reasoning: the stability of the causal relationship.


Asunto(s)
Formación de Concepto , Juicio , Modelos Psicológicos , Solución de Problemas , Humanos
19.
Pediatr Int ; 60(5): 446-454, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29415337

RESUMEN

BACKGROUND: Chronic Helicobacter pylori infection in children induces lymphoid hyperplasia called nodular gastritis (NG) at the antral gastric mucosa. The aim of this study was to evaluate genes in gastric biopsy on microarray analysis, to identify molecules associated with NG on comparison with NG-negative pediatric corpus tissue and with H. pylori-infected adult tissue with atrophic gastritis (AG). METHODS: Eight pediatric and six adult H. pylori-infected patients, as well as six pediatric and six adult uninfected patients were evaluated. All infected adults had AG. NG was observed in the antrum of all eight pediatric patients and in the corpus of three patients. Adult and uninfected patients were free of NG; that is, only pediatric H. pylori-infected patients had NG. Total RNA was purified from gastric biopsy, and microarray analysis was performed to compare gene expression between groups. The three infected children with NG in both the antrum and corpus were excluded from analysis of corpus samples. RESULTS: The number of genes significantly up- or downregulated (fold change >3, P < 0.01) compared with uninfected controls varied widely: 72 in pediatric antrum, 45 in pediatric corpus, 103 in adult antrum and 71 in adult corpus. Nineteen genes had significantly altered expression in the antrum of NG tissue compared with NG-negative pediatric corpus tissue and adult AG tissue. The CD20 B-cell specific differentiation antigen had the most pronounced increase. Previously described regulators of NG development were not predominantly upregulated in the NG mucosa. CONCLUSIONS: CD20 overexpression may play an important role in lymphoid follicle enlargement and NG.


Asunto(s)
Gastritis/genética , Infecciones por Helicobacter/complicaciones , Estómago/patología , Adolescente , Adulto , Niño , Preescolar , Femenino , Gastritis/complicaciones , Predisposición Genética a la Enfermedad , Helicobacter pylori , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos
20.
Cogn Sci ; 42(4): 1345-1359, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29160570

RESUMEN

Occam's razor-the idea that all else being equal, we should pick the simpler hypothesis-plays a prominent role in ordinary and scientific inference. But why are simpler hypotheses better? One attractive hypothesis known as Bayesian Occam's razor (BOR) is that more complex hypotheses tend to be more flexible-they can accommodate a wider range of possible data-and that flexibility is automatically penalized by Bayesian inference. In two experiments, we provide evidence that people's intuitive probabilistic and explanatory judgments follow the prescriptions of BOR. In particular, people's judgments are consistent with the two most distinctive characteristics of BOR: They penalize hypotheses as a function not only of their numbers of free parameters but also as a function of the size of the parameter space, and they penalize those hypotheses even when their parameters can be "tuned" to fit the data better than comparatively simpler hypotheses.


Asunto(s)
Teorema de Bayes , Probabilidad , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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