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1.
Front Cell Infect Microbiol ; 14: 1368622, 2024.
Article in English | MEDLINE | ID: mdl-38741889

ABSTRACT

There is scarce information concerning the role of sporadic clones in the dissemination of antimicrobial resistance genes (ARGs) within the nosocomial niche. We confirmed that the clinical Escherichia coli M19736 ST615 strain, one of the first isolates of Latin America that harbors a plasmid with an mcr-1 gene, could receive crucial ARG by transformation and conjugation using as donors critical plasmids that harbor bla CTX-M-15, bla KPC-2, bla NDM-5, bla NDM-1, or aadB genes. Escherichia coli M19736 acquired bla CTX-M-15, bla KPC-2, bla NDM-5, bla NDM-1, and aadB genes, being only blaNDM-1 maintained at 100% on the 10th day of subculture. In addition, when the evolved MDR-E. coli M19736 acquired sequentially bla CTX-M-15 and bla NDM-1 genes, the maintenance pattern of the plasmids changed. In addition, when the evolved XDR-E. coli M19736 acquired in an ulterior step the paadB plasmid, a different pattern of the plasmid's maintenance was found. Interestingly, the evolved E. coli M19736 strains disseminated simultaneously the acquired conjugative plasmids in different combinations though selection was ceftazidime in all cases. Finally, we isolated and characterized the extracellular vesicles (EVs) from the native and evolved XDR-E. coli M19736 strains. Interestingly, EVs from the evolved XDR-E. coli M19736 harbored bla CTX-M-15 though the pDCAG1-CTX-M-15 was previously lost as shown by WGS and experiments, suggesting that EV could be a relevant reservoir of ARG for susceptible bacteria. These results evidenced the genetic plasticity of a sporadic clone of E. coli such as ST615 that could play a relevant transitional link in the clinical dynamics and evolution to multidrug/extensively/pandrug-resistant phenotypes of superbugs within the nosocomial niche by acting simultaneously as a vector and reservoir of multiple ARGs which later could be disseminated.


Subject(s)
Anti-Bacterial Agents , Escherichia coli Infections , Escherichia coli , Gene Transfer, Horizontal , Plasmids , beta-Lactamases , Escherichia coli/genetics , Escherichia coli/drug effects , Plasmids/genetics , Humans , Escherichia coli Infections/microbiology , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Conjugation, Genetic , Escherichia coli Proteins/genetics , Drug Resistance, Multiple, Bacterial/genetics , Microbial Sensitivity Tests , Latin America , Drug Resistance, Bacterial/genetics
2.
Curr Microbiol ; 81(3): 76, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38267719

ABSTRACT

Two metallo-ß-lactamase-producing Klebsiella pneumoniae (HA30 and HA31) were isolated in a hospital in Argentina during 2018. K. pneumoniae HA30 was isolated from a rectal swab during the epidemiological surveillance for carbapenemase-producing strains, while K. pneumoniae HA31 was collected from the same patient 4 days after hospitalization. The aim of the present study was to identify the clonal relationships and resistome of these two NDM-producing K. pneumoniae strains isolated from a patient with a fatal outcome. Whole-genome sequencing (WGS) was performed using Illumina MiSeq-I, and subsequent analysis involved genome assembly, annotation, antibiotic resistance gene identification, multilocus sequence typing (MLST), and plasmid characterization using bioinformatics tools. Conjugation assays to E. coli J53 was conducted as previously described. K. pneumoniae HA30 exhibited extensively drug-resistant phenotype, while HA31 was multidrug-resistant as defined by Magiorakos et al., including both resistance to carbapenems, aminoglycosides and ciprofloxacin with blaNDM-5, blaCTX-M-15 and rmtB genes found in both strains. MLST analysis showed that both strains belonged to ST11, differing by only 4 cgSNPs, indicating that K. pneumoniae HA30 and HA31 were the same strain. Conjugation assays revealed that K. pneumoniae HA31 strain possessed a transferable plasmid to E. coli J53. Bioinformatics studies identified that the same strain colonizing an inpatient during hospital admission subsequently caused the infection leading to a fatal outcome, being the first report of blaNDM-5, rmtB and blaCTX-M-15 genes in a K. pneumoniae ST11 strain from Latin America. Our results also highlighted the importance of focusing on epidemiological surveillance programs.


Subject(s)
Escherichia coli , Klebsiella pneumoniae , Humans , Klebsiella pneumoniae/genetics , Multilocus Sequence Typing , Genomics , Anti-Bacterial Agents/pharmacology , beta-Lactamases/genetics
3.
Sci Rep ; 13(1): 15032, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37699939

ABSTRACT

Anguilliform swimmers, like eels or lampreys, are highly efficient swimmers. Key to understanding their performances is the relationship between the body's kinematics and resulting swimming speed and efficiency. But, we cannot prescribe kinematics to living fish, and it is challenging to measure their power consumption. Here, we characterise the swimming speed and cost of transport of a free-swimming undulatory bio-inspired robot as we vary its kinematic parameters, including joint amplitude, body wavelength, and frequency. We identify a trade-off between speed and efficiency. Speed, in terms of stride length, increases for increasing maximum tail angle, described by the newly proposed specific tail amplitude and reaches a maximum value around the specific tail amplitude of unity. Efficiency, in terms of the cost of transport, is affected by the whole-body motion. Cost of transport decreases for increasing travelling wave-like kinematics, and lower specific tail amplitudes. Our results suggest that live eels tend to choose efficiency over speed and provide insights into the key characteristics affecting undulatory swimming performance.


Subject(s)
Robotics , Animals , Swimming , Eels , Lampreys , Motion
4.
Salud UNINORTE ; 39(1)abr. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1536828

ABSTRACT

La diabetes mellitus es una patología metabòlica que altera los niveles de glucosa en el cuerpo, siendo más prevalente la tipo 2, la cual puede llegar a modular enfermedades sistémicas que causan diferentes desórdenes metabòlicos y cambios celulares. En cuanto a las alteraciones oftalmológicas, se pueden resaltar la retinopatía diabética y el ojo seco, siendo esta última una condición inflamatoria crónica que ocaciona daños en la superficie ocular. Por lo tanto, esta revisión brindará información de los factores asociados al desarrollo de ojo seco en la diabetes, resaltando cambios en la glicemia y el rol del metabolismo de glucosa sobre estructuras oculares tales como como la glándula lagrimal, glándulas de Meibomio, y en la microvasculatura, que pueden condicionar a trastornos neuropáticos que conducen a la sintomatologia ocular. De igual modo, se describen eventos biológicos como cambios en la expresión epigenética, estrés oxidativo e inflamación que presumiblemente juegan un papel importante en las diabetes y ojo seco, por lo cual la evaluación y análisis de la lágrima en esta población se hace necesaria, teniendo en cuenta los cambios en las estructuras oculares en la diabetes y las novedosas investigaciones sobre biomarcadores de diabetes a través de la película lagrimal.


Diabetes mellitus is a metabolic pathology that alters glucose levels in the body, being type 2 more prevalent, which can lead to modular systemic diseases that cause different metabolic disorders and cellular changes. Regarding ophthalmological alterations, diabetic retinopathy and dry eye can be highlighted, the latter being a chronic inflammatory condition causing damage to the ocular surface. Therefore, this review will provide information on the factors associated with the development of the dry eye in diabetes, highlighting changes in glycemia and the role of glucose metabolism on ocular structures such as the lacrimal gland, Meibomian glands, and the microvasculature, which can condition neuropathic disorders that lead to ocular symptoms, biological events such as changes in epigenetic expression, oxidative stress, and inflammation are prescribed, which presumably play an important role in diabetes and dry eye, for which the evaluation and analysis of tears in this population is done necessary, taking into account the changes in the ocular structures in diabetes and the new research on biomarkers of diabetes through the tear film.

5.
J Glob Antimicrob Resist ; 32: 108-112, 2023 03.
Article in English | MEDLINE | ID: mdl-36708770

ABSTRACT

OBJECTIVES: The worldwide dissemination of carbapenemase-producing Escherichia coli lineages belonging to high-risk clones poses a challenging public health menace. The aim of this work was to investigate genomic features of a colonizing multidrug-resistant strain of Klebsiella pneumoniae carbapenemase (KPC)-producing E. coli from our institution. METHODS: Whole-genome sequencing was done by Illumina MiSeq-I, and de novo assembly was achieved using SPAdes. Resistome, mobilome, plasmids, virulome, and integrons were analysed using ResFinder, AMRFinder, ISFinder, PlasmidFinder, MOB-suite, VirulenceFinder, and IntegronFinder. Sequence types (STs) were identified with pubMLST and BIGSdb databases. Conjugation assays were also performed. RESULTS: Escherichia coli HA25pEc was isolated from a rectal swab sample taken within the framework of the hospital epidemiological surveillance protocol for detection of carbapenemase-producing Enterobacterales. Escherichia coli HA25pEc corresponded to the first report of ST648 co-harbouring blaKPC-2 and blaCTX-M-15 in Latin America from a colonized patient. It had 19 antibiotic resistance genes (ARGs), including blaKPC-2, located on a Tn4401a isoform. Conjugation assays revealed that blaKPC-2 was not transferred by conjugation to E. coli J53 under our experimental conditions. CONCLUSION: Escherichia coli ST648 has been detected previously in companion and farm animals as well as in hospital- and community-acquired infections worldwide. Although scarcely reported as KPC-producers, our finding in a culture surveillance with several acquired ARGs, including blaCTX-M-15, alerts the potential of this clone for worldwide unnoticed spreading of extreme drug resistance to ß-lactams. These data reinforce the importance of carrying out molecular surveillance to identify reservoirs and warn about the dissemination of new international clones in carbapenemase-bearing patients.


Subject(s)
Drug Resistance, Multiple, Bacterial , Escherichia coli , Escherichia coli/genetics , Drug Resistance, Multiple, Bacterial/genetics , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Klebsiella pneumoniae , Genomics , Hospitals
6.
Mol Neurobiol ; 59(8): 5236-5251, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35689166

ABSTRACT

Spinocerebellar ataxia type 7 (SCA7) and other polyglutamine (polyQ) diseases are caused by expansions of polyQ repeats in disease-specific proteins. Aggregation of the polyQ proteins resulting in various forms of cellular stress, that could induce the stress granule (SG) response, is believed to be a common pathological mechanism in these disorders. SGs can contribute to cell survival but have also been suggested to exacerbate disease pathology by seeding protein aggregation. In this study, we show that two SG-related proteins, TDP-43 and TIA1, are sequestered into the aggregates formed by polyQ-expanded ATXN7 in SCA7 cells. Interestingly, mutant ATXN7 also localises to induced SGs, and this association altered the shape of the SGs. In spite of this, neither the ability to induce nor to disassemble SGs, in response to arsenite stress induction or relief, was affected in SCA7 cells. Moreover, we could not observe any change in the number of ATXN7 aggregates per cell following SG induction, although a small, non-significant, increase in total aggregated ATXN7 material could be detected using filter trap. However, mutant ATXN7 expression in itself increased the speckling of the SG-nucleating protein G3BP1 and the SG response. Taken together, our results indicate that the SG response is induced, and although some key modulators of SGs show altered behaviour, the dynamics of SGs appear normal in the presence of mutant ATXN7.


Subject(s)
DNA Helicases , Spinocerebellar Ataxias , Ataxin-7/metabolism , Cytoplasmic Granules/metabolism , DNA Helicases/metabolism , DNA-Binding Proteins/metabolism , Humans , Peptides , Poly-ADP-Ribose Binding Proteins/metabolism , RNA Helicases/metabolism , RNA Recognition Motif Proteins/metabolism , Spinocerebellar Ataxias/genetics , Stress Granules , T-Cell Intracellular Antigen-1/metabolism
7.
Microb Pathog ; 163: 105378, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34982979

ABSTRACT

Escherichia coli is an important cause of septicemia (SEPEC) and neonatal meningitis (NMEC) in dairy calves. However, the diversity of virulence profiles, phylogroups, antimicrobial resistance patterns, carriage of integron structures, and fluoroquinolone (FQ) resistance mechanisms have not been fully investigated. Also, there is a paucity of knowledge about the virulence profiles and frequency of potential SEPEC in feces from calves with or without diarrhea. This study aimed to characterize the virulence potential, phylogroups, antimicrobial susceptibility, integron content, and FQ-resistance mechanisms in Escherichia coli isolated from calves with meningitis and septicemia. Additionally, the virulence genes (VGs) and profiles of E. coli isolated from diarrheic and non-diarrheic calves were compared between them and together with NMEC and SEPEC in order to identify shared profiles. Tissue and fluid samples from eight dairy calves with septicemia, four of which had concurrent meningitis, were processed for bacteriology and histopathology. Typing of VGs was assessed in 166 isolates from diverse samples of each calf. Selected isolates were evaluated for antimicrobial susceptibility by the disk diffusion test. Phylogroups, integron gene cassettes cartography, and FQ-resistance determinants were analyzed by PCR, sequencing, and bioinformatic tools. Furthermore, 109 fecal samples and 700 fecal isolates from dairy calves with or without diarrhea were evaluated to detect 19 VGs by uniplex PCR. Highly diverse VG profiles were characterized among NMEC and SEPEC isolates, but iucD was the predominant virulence marker. Histologic lesions in all calves supported their pathogenicity. Selected isolates mainly belonged to phylogroups A and C and showed multidrug resistance. Classic (dfrA17 and arr3-dfrA27) and complex (dfrA17-aadA5::ISCR1::blaCTX-M-2) class 1 integrons were identified. Target-site mutations in GyrA (S83L and D87N) and ParC (S80I) encoding genes were associated with FQ resistance. The VGs detected more frequently in fecal samples included f17G (50%), papC (30%), iucD (20%), clpG (19%), eae (16%), and afaE-8 (13%). Fecal isolates displaying the profiles of f17 or potential SEPEC were found in 25% of calves with and without diarrhea. The frequency of E. coli VGs and profiles did not differ between both groups (p > 0.05) and were identical or similar to those found in NMEC and SEPEC. Overall, multidrug-resistant E. coli isolates with diverse VG profiles and belonging to phylogroups A and C can be implicated in natural cases of meningitis and septicemia. Their resistance phenotypes can be partially explained by class 1 integron gene cassettes and target-site mutations in gyrA and parC. These results highlight the value of antimicrobial resistance surveillance in pathogenic bacteria isolated from food-producing animals. Besides, calves frequently shed potential SEPEC in their feces as commensals ("Trojan horse"). Thus, these bacteria may be disseminated in the farm environment, causing septicemia and meningitis under predisposing factors.


Subject(s)
Escherichia coli Infections , Meningitis , Sepsis , Animals , Anti-Bacterial Agents/pharmacology , Cattle , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/genetics , Escherichia coli Infections/veterinary , Integrons , Sepsis/veterinary
8.
Sci Robot ; 6(57)2021 08 11.
Article in English | MEDLINE | ID: mdl-34380756

ABSTRACT

Undulatory swimming represents an ideal behavior to investigate locomotion control and the role of the underlying central and peripheral components in the spinal cord. Many vertebrate swimmers have central pattern generators and local pressure-sensitive receptors that provide information about the surrounding fluid. However, it remains difficult to study experimentally how these sensors influence motor commands in these animals. Here, using a specifically designed robot that captures the essential components of the animal neuromechanical system and using simulations, we tested the hypothesis that sensed hydrodynamic pressure forces can entrain body actuation through local feedback loops. We found evidence that this peripheral mechanism leads to self-organized undulatory swimming by providing intersegmental coordination and body oscillations. Swimming can be redundantly induced by central mechanisms, and we show that, therefore, a combination of both central and peripheral mechanisms offers a higher robustness against neural disruptions than any of them alone, which potentially explains how some vertebrates retain locomotor capabilities after spinal cord lesions. These results broaden our understanding of animal locomotion and expand our knowledge for the design of robust and modular robots that physically interact with the environment.

9.
Arch Plast Surg ; 48(1): 107-113, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33503753

ABSTRACT

BACKGROUND: Applicants to integrated plastic and reconstructive surgery (PRS) residency in the United States spend exorbitant amounts of time and money throughout the interview process. Outside of first-hand experience through a visiting rotation, applicants utilize various resources in learning about a program. Today's applicants are "Millennials," the demographic cohort raised during the information age and proficient with digital technology. The authors evaluated whether programs have a presence on social media, and whether applicants are following these accounts. METHODS: An online survey was sent to applicants to a single integrated plastic surgery program evaluating basic demographics, social media utilization, and sources of information accessed throughout the residency application process. A manual search of popular social media platforms (Instagram, Facebook, and Twitter) was performed in October 2019. Accounts affiliated with integrated PRS programs were identified and analyzed. RESULTS: Eighty-four of 222 applicants (37.8%) completed the survey. Ninety-six percent of applicants were within the Millennial demographic. Ninety-six percent of applicants had some form of social media presence, with Facebook (90%) and Instagram (87%) being the most popular platforms. Seventy-three percent of applicants reported following a PRS residency social media account. As of October 2019, 59 integrated residency programs (73%) have active Instagram accounts. CONCLUSIONS: Applicants still rely on the program website when researching potential residencies, but social media is being rapidly adopted by programs. Program social media accounts should be used as a dynamic form of communication to better inform applicants of program strengths and weaknesses.

10.
Nanotheranostics ; 4(3): 107-118, 2020.
Article in English | MEDLINE | ID: mdl-32328438

ABSTRACT

Nanoparticles offer many promising advantages for improving current surgical regimens through their ability to detect and treat disseminated colorectal cancer (CRC). Hybrid Donor-Acceptor Polymer Particles (HDAPPs) have recently been shown to fluorescently detect and thermally ablate tumors in a murine model. Here, HDAPPS were functionalized with hyaluronic acid (HA) to improve their binding specificity to CT26 mouse CRC cells using HA to target the cancer stem cell marker CD44. In this work, we compared the binding of HA functionalized HDAPPs (HA-HDAPPs) in in vitro, ex vivo, and in vivo environments. The HA-HDAPPs bound to CT26 cells 2-fold more in vitro and 2.3-fold higher than un-functionalized HDAPPs ex vivo. Compared to intraoperative abdominal perfusion, intraperitoneal injection prior to laser stimulation for nanoparticle heat generation provides a superior modality of HA-HDAPPs delivery for CRC tumor selectivity. Photothermal treatment of disseminated CRC showed that only HA-HDAPPs delivered via intraperitoneal injection had a reduction in the tumor burden, and these nanoparticles also remained in the abdomen following resolution of the tumor. The results of this work confirm that HA-HDAPPs selectively bind to disseminated CRC, with ex vivo tumors having bound HA-HDAPPs capable of photothermal ablation. HA-HDAPPs demonstrated superior binding to tumor regions compared to HDAPPs. Overall, this study displays the theranostic potential of HDAPPs, emphasizing their capacity to detect and photothermally treat disseminated CRC tumors.


Subject(s)
Antineoplastic Agents , Colorectal Neoplasms , Drug Delivery Systems/methods , Peritoneal Cavity/diagnostic imaging , Quantum Dots , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Cell Line, Tumor , Colorectal Neoplasms/diagnostic imaging , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Fluorescent Dyes/chemistry , Fluorescent Dyes/metabolism , Hyaluronic Acid/chemistry , Hyaluronic Acid/metabolism , Mice , Optical Imaging , Quantum Dots/chemistry , Quantum Dots/metabolism , Theranostic Nanomedicine
11.
Clin Immunol ; 212: 108346, 2020 03.
Article in English | MEDLINE | ID: mdl-31954803

ABSTRACT

Previous studies showed that circulating autoantibodies against M2 muscarinic receptors (anti-M2R Ab) are associated with decreased cardiac parasympathetic modulation in patients with chronic Chagas disease (CD). Here we investigated whether the exposure of M2R to such antibodies could impair agonist-induced receptor activation, leading to the inhibition of associated signaling pathways. Preincubation of M2R-expressing HEK 293T cells with serum IgG fractions from chagasic patients with cardiovascular dysautonomia, followed by the addition of carbachol, resulted in the attenuation of agonist-induced Gi protein activation and arrestin-2 recruitment. These effects were not mimicked by the corresponding Fab fractions, suggesting that they occur through receptor crosslinking. IgG autoantibodies did not enhance M2R/arrestin interaction or promote M2R internalization, suggesting that their inhibitory effects are not likely a result of short-term receptor regulation. Rather, these immunoglobulins could function as negative allosteric modulators of acetylcholine-mediated responses, thereby contributing to the development of parasympathetic dysfunction in patients with CD.


Subject(s)
Autoantibodies/immunology , Autonomic Nervous System Diseases/immunology , Chagas Disease/immunology , Receptor, Muscarinic M2/immunology , Adult , Aged , Allosteric Regulation , Autoantibodies/metabolism , Autoantibodies/pharmacology , Autonomic Nervous System Diseases/etiology , Autonomic Nervous System Diseases/metabolism , Autonomic Nervous System Diseases/physiopathology , Carbachol/pharmacology , Chagas Disease/complications , Chagas Disease/metabolism , Chagas Disease/physiopathology , Cholinergic Agonists/pharmacology , Female , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , GTP-Binding Protein alpha Subunits, Gq-G11/metabolism , HEK293 Cells , Heart Rate , Humans , Male , Middle Aged , Receptor, Muscarinic M2/drug effects , Receptor, Muscarinic M2/metabolism , beta-Arrestin 1/metabolism
12.
J Surg Res ; 233: 310-322, 2019 01.
Article in English | MEDLINE | ID: mdl-30502264

ABSTRACT

BACKGROUND: Reproduction of the perfusion used in therapy (hyperthermic intraperitoneal chemotherapy) procedures preclinically represents a valuable asset for investigating new therapeutic agents that may improve patient outcomes. This article provides technical descriptions of our execution of closed and open "coliseum" abdominal perfusion techniques in a mouse model of peritoneal carcinomatosis of colorectal cancer. MATERIALS AND METHODS: BALB/c mice presenting with disseminated colorectal cancer (CT26-luciferin cells) underwent 30-min perfusions mimicking either the closed perfusion or the coliseum perfusion technique. Disease burden was monitored by bioluminescence signaling using an in vivo imaging system. Perfusion circuits consisted of single inflow lines with either a single or dual outflow line. RESULTS: Twelve mice presenting with disseminated disease underwent the closed perfusion technique. Surgical complications included perfusate leakage and organ constriction/suction into the outflow line(s). Nine mice underwent the coliseum perfusion technique with surgical debulking, using bipolar cauterization to remove tumors attached to the peritoneum. All mice survived the coliseum perfusion with limited intraoperative complications. CONCLUSIONS: Fewer intraoperative complications were experienced with our coliseum perfusion technique than the closed perfusion. The methods described here can be used as a guideline for developing future perfusion murine models for investigating perfusion models useful for delivery of chemotherapy or other tumor-sensitization agents, including selective targeted agents, nanoparticles, and heat.


Subject(s)
Antineoplastic Agents/administration & dosage , Chemotherapy, Cancer, Regional Perfusion/methods , Colorectal Neoplasms/therapy , Hyperthermia, Induced/methods , Peritoneal Neoplasms/therapy , Animals , Cell Line, Tumor/transplantation , Chemotherapy, Cancer, Regional Perfusion/adverse effects , Chemotherapy, Cancer, Regional Perfusion/instrumentation , Colorectal Neoplasms/pathology , Combined Modality Therapy/adverse effects , Combined Modality Therapy/instrumentation , Combined Modality Therapy/methods , Disease Models, Animal , Female , Humans , Hyperthermia, Induced/adverse effects , Hyperthermia, Induced/instrumentation , Intraoperative Complications/epidemiology , Intraoperative Complications/etiology , Mice , Mice, Inbred BALB C , Peritoneal Neoplasms/secondary , Treatment Outcome
13.
J Biol Chem ; 293(5): 1666-1675, 2018 02 02.
Article in English | MEDLINE | ID: mdl-29180450

ABSTRACT

It has been suggested that voltage-dependent anion channels (VDACs) control the release of superoxide from mitochondria. We have previously shown that reactive oxygen species (ROS) such as superoxide (O2̇̄) and hydrogen peroxide (H2O2) stimulate epithelial sodium channels (ENaCs) in sodium-transporting epithelial tissue, including cortical collecting duct (CCD) principal cells. Therefore, we hypothesized that VDACs could regulate ENaC by modulating cytosolic ROS levels. Herein, we find that VDAC3-knockout(KO) mice can maintain normal salt and water balance on low-salt and high-salt diets. However, on a high-salt diet for 2 weeks, VDAC3-KO mice had significantly higher systolic blood pressure than wildtype mice. Consistent with this observation, after a high-salt diet for 2 weeks, ENaC activity in VDAC3-KO mice was significantly higher than wildtype mice. EM analysis disclosed a significant morphological change of mitochondria in the CCD cells of VDAC3-KO mice compared with wildtype mice, which may have been caused by mitochondrial superoxide overload. Of note, compared with wildtype animals, ROS levels in VDAC3-KO animals fed a normal or high-salt diet were consistently and significantly increased in renal tubules. Both the ROS scavenger 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine (TEMPOL) and the mitochondrial ROS scavenger (2-(2,2,6,6-tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride (mito-TEMPO) could reverse the effect of high-salt on ENaC activity and systolic blood pressure in the VDAC3-KO mice. Mito-TEMPO partially correct the morphological changes in VDAC3-KO mice. Our results suggest that knocking out mitochondrial VDAC3 increases ROS, alters renal sodium transport, and leads to hypertension.


Subject(s)
Epithelial Sodium Channels/metabolism , Hydrogen Peroxide/metabolism , Kidney/metabolism , Mitochondria/metabolism , Mitochondrial Membrane Transport Proteins/deficiency , Sodium/metabolism , Superoxides/metabolism , Voltage-Dependent Anion Channels/deficiency , Animals , Blood Pressure/drug effects , Blood Pressure/genetics , Cyclic N-Oxides/pharmacology , Epithelial Sodium Channels/genetics , Hypertension/genetics , Hypertension/metabolism , Hypertension/pathology , Ion Transport/drug effects , Ion Transport/genetics , Kidney/pathology , Mice , Mice, Knockout , Mitochondria/genetics , Mitochondria/pathology , Mitochondrial Membrane Transport Proteins/metabolism , Organophosphorus Compounds/pharmacology , Piperidines/pharmacology , Spin Labels , Voltage-Dependent Anion Channels/metabolism
14.
Cir. parag ; 41(1): 33-35, abr. 2017. ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-972600

ABSTRACT

La arteritis actínica es la lesión producida a las arterias por la exposición a radiaciones ionizantes utilizadas previamente para el tratamiento radioterápico por diagnóstico de una neoplasia maligna y se presenta tras años de la exposición. Presentamos el caso de una paciente con antecedentes de Cáncer del canal anal con exposición a radioterapia en zona pélvica 21 años atrás que presento síntomas 8 años antes con signos de isquemia progresiva recibiendo tratamiento médico hasta llegar a isquemia critica en el miembro inferior izquierdo 7 meses antes con dolor en reposo y presentar lesión en hallux izquierdo 15 días antes de su internación, por lo que tras el fallo del tratamiento médico se optó por la revascularización con la realización de un By Pass extra anatómico.


Actinic arteritis is the lesion produced in the arteries by exposure to ionizing radiation previously used for radiotherapy treatment by diagnosis of a malignant neoplasm and occurs after years of exposure. We present the case of a patient with a history of anal canal cancer with exposure to pelvic radiotherapy 21 years ago who presented symptoms 8 years earlier with signs of progressive ischemia receiving medical treatment until critical ischemia in the left lower limb 7 months before With pain at rest and present lesion in the left hallux 15 days before their hospitalization, so that after the failure of the medical treatment was revascularization with the realization of an extra anatomical By Pass.


Subject(s)
Female , Humans , Aged , Arterial Occlusive Diseases/diagnosis , Arterial Occlusive Diseases/surgery , Neoplasms , Radiotherapy
15.
J Biol Chem ; 290(48): 28805-11, 2015 Nov 27.
Article in English | MEDLINE | ID: mdl-26451045

ABSTRACT

The renal epithelial sodium channel (ENaC) provides regulated sodium transport in the distal nephron. The effects of intracellular calcium ([Ca(2+)]i) on this channel are only beginning to be elucidated. It appears from previous studies that the [Ca(2+)]i increases downstream of ATP administration may have a polarized effect on ENaC, where apical application of ATP and the subsequent [Ca(2+)]i increase have an inhibitory effect on the channel, whereas basolateral ATP and [Ca(2+)]i have a stimulatory effect. We asked whether this polarized effect of ATP is, in fact, reflective of a polarized effect of increased [Ca(2+)]i on ENaC and what underlying mechanism is responsible. We began by performing patch clamp experiments in which ENaC activity was measured during apical or basolateral application of ionomycin to increase [Ca(2+)]i near the apical or basolateral membrane, respectively. We found that ENaC does indeed respond to increased [Ca(2+)]i in a polarized fashion, with apical increases being inhibitory and basolateral increases stimulating channel activity. In other epithelial cell types, mitochondria sequester [Ca(2+)]i, creating [Ca(2+)]i signaling microdomains within the cell that are dependent on mitochondrial localization. We found that mitochondria localize in bands just beneath the apical and basolateral membranes in two different cortical collecting duct principal cell lines and in cortical collecting duct principal cells in mouse kidney tissue. We found that inhibiting mitochondrial [Ca(2+)]i uptake destroyed the polarized response of ENaC to [Ca(2+)]i. Overall, our data suggest that ENaC is regulated by [Ca(2+)]i in a polarized fashion and that this polarization is maintained by mitochondrial [Ca(2+)]i sequestration.


Subject(s)
Calcium Signaling/physiology , Calcium/metabolism , Epithelial Sodium Channels/metabolism , Kidney Tubules, Collecting/metabolism , Mitochondria/metabolism , Adenosine Triphosphate/metabolism , Animals , Cell Line , Mice , Xenopus laevis
16.
Cir. parag ; 39(1): 28-32, jun. 2015. ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-972568

ABSTRACT

La fístula aortobronquial (FAB) es una comunicación patológica entre la aorta torácica y el árbol bronquial, habitualmente del hemitórax izquierdo. Se trata de un cuadro muy poco frecuente en la actualidad, aunque letal si no se realiza un diagnóstico certero de forma temprana. El principal síntoma es la hemoptisis intermitente que a su vez puede ser leve, moderada y en ocasiones masiva. Debe sospecharse en pacientes con antecedente de cirugía cardíaca o de la aorta torácica, traumatismo de tórax o aneurisma aterosclerótico o infecciosos de la aorta torácica, rara vez una úlcera penetrante. El objetivo es reportar 2 casos de FAB en un Servicio de Cirugía Vascular, uno de ellos posterior a cirugía de corrección de coartación de aorta torácica descendente luego de 12 años, otro a causa de una úlcera aórtica penetrante en aorta torácica descendente, en ambos casos la hemoptisis fue el síntoma principal, y el tratamiento se realizó de forma exitosa por vía endovascular.


Subject(s)
Female , Humans , Adult , Aged , Aorta, Thoracic , Bronchial Fistula , Hemoptysis
17.
NOVA publ. cient ; 13(23): 19-31, ene.-jun. 2015. ilus, tab
Article in Spanish | LILACS, COLNAL | ID: lil-759072

ABSTRACT

Objetivo. Estandarizar el cultivo de células HeLa en diferentes condiciones, con el fin de utilizarlo en protocolos de infección con Chlamydia trachomatis serovar L2. Materiales y métodos. Este estudio se llevó a cabo en cuatro fases principales que son: 1.Viabilidad celular por la técnica de azul de tripán y su posterior observación, 2. Estandarización del cultivo de células HeLa, 3. Coloración de Giemsa, 4. Cultivo de células HEp-2.Resultados. Se determinó que la línea celular HeLa debe ser cultivada en medio DMEM, 0,1% de L- glutamina, 10% de SFB. Así mismo, que la coloración de Giemsa es mejor realizarla en un tiempo de 40 minutos por que se evidencia una clara definición de núcleo y citoplasma. Frente a la comparación de las dos líneas celulares se obtuvo que la línea HeLa desde el primer día muestra un crecimiento adecuado y alcanza rápidamente la confluencia esperada, en contraposición la línea HEp-2 presenta un crecimiento más lento pero alcanzando la confluencia deseada al último día.


Objective. The goal of this study was to standardize the cultivation of HeLa cells under different conditions, to be used in Chlamydia trachomatis serovar L2 infection's protocols. Materials and Methods. This study was conducted in four phases that are: 1.Cell Viabilidad by trypan blue technique and his subsequent remark, 2. Standardization HeLa cell culture, 3. Giemsa, 4. Cultivation of Hep-2 cells. Results. As a result of standardization it is determined that the HeLa cell line should be cultured in DMEM, 0.1% L-glutamine, 10% FBS.It was determined that the Giemsa perform better over time of 40 minutes that a clear definition of nucleus and cytoplasm is evident. Comparing against both cell lines HeLa was obtained that the line from day growing well and quickly reaches the expected confluence, the opposed line HEp-2 has a slower growth but achieving the desired confluence the last day.


Subject(s)
Humans , Chlamydia trachomatis , HeLa Cells , Cell Culture Techniques , Infections
18.
Glob Health Action ; 6: 23061, 2013 Dec 27.
Article in English | MEDLINE | ID: mdl-24378195

ABSTRACT

BACKGROUND: The integration of mental and neurologic services in healthcare is a global priority. The universal Social Security of Costa Rica aspires to develop national screening of neurodegenerative disorders among the elderly, as part of the non-communicable disease agenda. OBJECTIVE: This study assessed the feasibility of routine screening for Parkinson's disease (PD) and Alzheimer's disease (AD) within the public healthcare system of Costa Rica. DESIGN: The population (aged ≥65) in the catchment areas of two primary healthcare clinics was targeted for motor and cognitive screening during routine annual health check-ups. The screening followed a tiered three-step approach, with increasing specificity. Step 1 involved a two-symptom questionnaire (tremor-at-rest; balance) and a spiral drawing test for motor assessment, as well as a three-word recall and animal category fluency test for cognitive assessment. Step 2 (for those failing Step 1) was a 10-item version of the Unified Parkinson Disease Rating Scale and the Mini-Mental State Examination. Step 3 (for those failing Step 2) was a comprehensive neurologic exam with definitive diagnosis of PD, AD, mild cognitive impairment (MCI), other disorders, or subjects who were healthy. Screening parameters and disease prevalence were calculated. RESULTS: Of the 401 screened subjects (80% of target population), 370 (92%), 163 (45%), and 81 (56%) failed in Step 1, Step 2, and Step 3, respectively. Thirty-three, 20, and 35 patients were diagnosed with PD, AD, and MCI, respectively (7 were PD with MCI/AD); 90% were new cases. Step 1 sensitivities of motor and cognitive assessments regarding Step 2 were both 93%, and Step 2 sensitivities regarding definitive diagnosis 100 and 96%, respectively. Specificities for Step 1 motor and cognitive tests were low (23% and 29%, respectively) and for Step 2 tests acceptable (76%, 94%). Based on international data, PD prevalence was 3.7 times higher than expected; AD prevalence was as expected. CONCLUSION: Proposed protocol adjustments will increase test specificity and reduce administration time. A routine screening program is feasible within the public healthcare system of Costa Rica.


Subject(s)
Alzheimer Disease/diagnosis , Alzheimer Disease/prevention & control , Delivery of Health Care, Integrated/organization & administration , Mass Screening/organization & administration , Parkinson Disease/diagnosis , Parkinson Disease/prevention & control , Public Health/methods , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Costa Rica/epidemiology , Feasibility Studies , Female , Humans , Male , Middle Aged , Parkinson Disease/epidemiology , Surveys and Questionnaires
19.
Pediatrics ; 113(5): e440-7, 2004 May.
Article in English | MEDLINE | ID: mdl-15121987

ABSTRACT

OBJECTIVE: The goal of this study was to examine the relative contributions of growth deficiency and psychosocial factors to cognitive development in toddlers with infantile anorexia. METHODS: Eighty-eight toddlers, ranging in age from 12 to 33 months, were enrolled in this study. Toddlers were evaluated by 2 child psychiatrists and placed into 1 of 3 groups: infantile anorexia, picky eater, and healthy eater. All 3 groups were matched for age, race, gender, and socioeconomic status (SES). Toddlers underwent nutritional evaluations and cognitive assessments with the Bayley Scales of Infant Development. Toddlers and their mothers were also videotaped during feeding and play interactions, which later were rated independently by 2 observers. RESULTS: On average, toddlers with infantile anorexia performed within the normal range of cognitive development. However, the Mental Developmental Index (MDI) scores of the healthy eater group (MDI = 110) were significantly higher than those of the infantile anorexia (MDI = 99) and picky eater (MDI = 96) groups. Within the infantile anorexia group, correlations between MDI scores and the toddlers' percentage of ideal body weight approached statistical significance (r =.32). Across all groups, the toddlers' MDI scores were associated with the quality of mother-child interactions, SES level, and maternal education level. Collectively, these variables explained 22% of the variance in MDI scores. CONCLUSIONS: This study demonstrated that psychosocial factors, such as mother-toddler interactions, maternal education level, and SES level, are related to the cognitive development of toddlers with feeding problems and explain more unique variance in MDI scores than nutritional status.


Subject(s)
Anorexia/physiopathology , Child Development , Cognition Disorders/etiology , Failure to Thrive/etiology , Maternal Behavior , Anorexia/complications , Child, Preschool , Educational Status , Humans , Infant , Socioeconomic Factors
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