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1.
Neurosci Bull ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937384

RESUMEN

The activity of occipitotemporal regions involved in linguistic reading processes, such as the ventral occipitotemporal cortex (vOT), is believed to exhibit strong interactions during higher-order language processing, specifically in the connectivity between the occipital gyrus and the temporal gyrus. In this study, we utilized functional magnetic resonance imaging (fMRI) with psychophysiological interaction (PPI) and dynamic causal modeling (DCM) to investigate the functional and effective connectivity in the occipitotemporal network during speed reading. We conducted the experiment with native Japanese speakers who underwent and without speed-reading training and subsequently performed established reading tasks at different speeds (slow, medium, and fast) while undergoing 3-Tesla Siemens fMRI. Our activation analyses revealed significant changes in occipital and temporal regions as reading speed increased, indicating functional connectivity within the occipitotemporal network. DCM results further demonstrated more intricate effective connections and high involvement within the occipitotemporal pathway: (1) reading signals originated from the inferior occipital gyrus (iO), distributed to the vOT and the posterior superior temporal sulcus (pSTS), and then gathered in the anterior superior temporal sulcus (aSTS); (2) reading speed loads had modulation effects on the pathways from the aSTS to vOT and from the iO to vOT. These findings highlight the complex connectivity and dynamic interactions within the occipitotemporal network during speed-reading processes.

2.
Zoolog Sci ; 41(1): 124-131, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38587525

RESUMEN

For adult anuran amphibians, the kidney and urinary bladder play important osmoregulatory roles through water reabsorption. In the present study, we have examined ontogenetic expression of aquaporins, i.e., AQP2, AQPamU (AQP6ub, AQPa2U), and AQP3, in these organs using the Japanese tree frog, Dryophytes japonicus. Immunohistochemistry using the metamorphosing larvae at stages 40-43 localized AQP2 protein to the collecting ducts in the dorsal zone of the mesonephric kidney. At prometamorphic stages 40 and 41, labelling of AQP2 protein was observed in the apical/ subapical regions of the collecting duct cells. At climax stages 42 and 43, labels for AQP2 and AQP3 became observed in the apical/subapical regions and basolateral membrane of the collecting duct cells, respectively, as seen in the adults. As for the urinary bladder, immuno-positive labels for AQPamU were localized to the apical/subapical regions of granular cells in the mucosal epithelium at stages 40-43. On the other hand, AQP3 immunoreactivity was hardly observed in the urinary bladder at stage 40, and weakly appeared in many granular cells at stage 41. Thereafter, labels for AQP3 became evident along the basolateral membrane of granular cells at stages 42 and 43, together with AQPamU in the apical/subapical regions. These results suggest that the kidney and urinary bladder might be capable of water reabsorption, via AQP2, AQPamU, and AQP3, at stage 42, contributing to the acclimation of the tree frogs to terrestrial environments.


Asunto(s)
Acuaporina 2 , Vejiga Urinaria , Animales , Japón , Anuros , Riñón , Agua
3.
J Nematol ; 532021.
Artículo en Inglés | MEDLINE | ID: mdl-33860256

RESUMEN

Anisakid nematodes are parasites of cetaceans, their larval stages live in marine fishes. The third-stage larvae of some Anisakis species are also the etiological agents of human anisakiasis caused by consumption of raw or undercooked infected fish. Thus, identification of Anisakis larvae at the species level is crucial for their ecology and epidemiology. In Vietnam, although Anisakis larvae have been reported, they have not been identified to the species level. The aim of this study was, therefore, to identify third-stage larvae of Anisakis collected from marine fishes in Vietnamese water, based on morphological characteristics and molecular analysis. All Anisakis larvae found in this study were morphologically similar to each other and identical to Anisakis typica. In addition, molecular analysis based on ITS1-5.8S-ITS2 sequences confirmed them as A. typica. Vietnamese A. typica population was genetically close to those from Asian countries and Australia. The third-stage larvae of A. typica were collected from eight fish species from three localities in the South of Vietnam. Among them, seven were recorded as new intermediate hosts of A. typica. This is the first identification of A. typica larvae in Vietnamese water with records of new fish hosts.

4.
Parasitol Res ; 120(3): 877-885, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33409633

RESUMEN

During a survey of myxosporean parasites of marine fish in the coastal region of Vietnam, a species of the genus Henneguya (Myxosporea: Bivalvulida) was found in the gill of yellowfin seabream Acanthopagrus latus (Perciformes: Sparidae). White and oval cysts, measuring 145-220 µm in diameter, were detected in the gill lamellae of 4 of 15 fish examined (26.7%). Mature myxospores were elongate, with smooth valves, two similar polar capsules, and having the following dimensions: spore body length 9.9 ± 0.5 (8.9-12.5) µm, body width 6.7 ± 0.3 (6.1-7.6) µm, thickness 5.1 ± 0.2 (4.8-5.4) µm, caudal appendage length 10.0 ± 1 (8.3-11.6) µm, and total myxospore length 19.3 ± 1.4 (16.5-21.5) µm. The polar capsules were ovoid, measuring 3.2 ± 0.2 (2.8-3.9) µm long and 1.9 ± 0.2 (1.5-2.3) µm wide. Each polar capsule has a polar filament with 4-5 coils. Histological analysis revealed plasmodia in the connective tissues of the gill lamellae, but inflammation and deformation of the gills were not observed. In the phylogenetic tree reconstructed from the small subunit ribosomal DNA (SSU rDNA), sequences of the Henneguya specimens found in this study form a distinct branch. Morphological characteristics and molecular data identified a new species, namely Henneguya lata n. sp.


Asunto(s)
Enfermedades de los Peces/parasitología , Branquias/parasitología , Myxozoa/aislamiento & purificación , Enfermedades Parasitarias en Animales/parasitología , Dorada/parasitología , Animales , Myxozoa/clasificación , Myxozoa/genética , Myxozoa/fisiología , Filogenia , Vietnam
5.
Quant Imaging Med Surg ; 11(1): 9-20, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33392007

RESUMEN

BACKGROUND: Proton magnetic resonance spectroscopy (MRS) provides a unique opportunity for in vivo measurements of the brain's metabolic profile. Two methods of mainstream data acquisition are compared at 7 T, which provides certain advantages as well as challenges. The two representative methods have seldom been compared in terms of measured metabolite concentrations and different scan times. The current study investigated proton MRS of the posterior cingulate cortex using a semi-localized by adiabatic selective refocusing (sLASER) sequence and a short echo time (TE) stimulated echo acquisition mode (sSTEAM) sequence, and it compared their reliability and repeatability at 7 T using a 32-channel head coil. METHODS: Sixteen healthy subjects were prospectively enrolled and scanned twice with an off-bed interval between scans. The scan parameters for sLASER were a TR/TE of 6.5 s/32 ms and 32 and 48 averages (sLASER×32 and sLASER×48, respectively). The scan parameters for sSTEAM were a TR/TE of 4 s/5 ms and 32, 48, and 64 averages (sSTEAM4×32, sSTEAM4×48, and sSTEAM4×64, respectively) in addition to that with a TR/TE of 8 s/5 ms and 32 averages (sSTEAM8×32). Data were analyzed using LCModel. Metabolites quantified with Cramér-Rao lower bounds (CRLBs) >50% were classified as not detected, and metabolites quantified with mean or median CRLBs ≤20% were included for further analysis. The SNR, CRLBs, coefficient of variation (CV), and metabolite concentrations were statistically compared using the Shapiro-Wilk test, one-way ANOVA, or the Friedman test. RESULTS: The sLASER spectra for N-acetylaspartate + N-acetylaspartylglutamate (tNAA) and glutamate (Glu) had a comparable or higher SNR than sSTEAM spectra. Ten metabolites had lower CRLBs than prefixed thresholds: aspartate (Asp), γ-aminobutyric acid (GABA), glutamine (Gln), Glu, glutathione (GSH), myo-inositol (Ins), taurine (Tau), the total amount of phosphocholine + glycerophosphocholine (tCho), creatine + phosphocreatine (tCr), and tNAA. Performance of the two sequences was satisfactory except for GABA, for which sLASER yielded higher CRLBs (≥18%) than sSTEAM. Some significant differences in CRLBs were noted, but they were ≤2% except for GABA and Gln. Signal averaging significantly lowered CRLBs for some metabolites but only by a small amount. Measurement repeatability as indicated by median CVs was ≤10% for Gln, Glu, Ins, tCho, tCr, and tNAA in all scans, and that for Asp, GABA, GSH, and Tau was ≥10% under some scanning conditions. The CV for GABA according to sLASER was significantly higher than that according to sSTEAM, whereas the CV for Ins was higher according to sSTEAM. An increase in signal averaging contribute little to lower CVs except for Ins. CONCLUSIONS: Both sequences quantified brain metabolites with a high degree of precision and repeatability. They are comparable except for GABA, for which sSTEAM would be a better choice.

6.
Transl Res ; 228: 94-108, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32835907

RESUMEN

Peripheral artery disease (PAD), a severe atherosclerotic condition primarily of the elderly, afflicts 200 million individuals, worldwide, and is associated with lower extremity myopathy. Circulating markers of inflammation have been linked to risk and severity of PAD but the contribution of local inflammation to myopathy remains unknown. We evaluated, by ELISA, calf muscle of PAD patients (N = 23) and control subjects (N = 18) for local expression of inflammatory cytokines including Granulocyte/Monocyte Colony-Stimulating Factor (GM-CSF), Interleukin 17A (IL-17A), Interferon ϒ (IFN-ϒ), tumor necrosis factor α (TNF-α), and Interleukin 6 (IL-6). One or more of these cytokines were expressed in nineteen patients and 2 controls and coordinated expression of GM-CSF, IL-17A, IFN-ϒ, and TNF-α, a signature of activated, MHC Class II dependent autoreactive Th-cells, was unique to 11 patients. GM-CSF is the central driver of tissue-damaging myeloid macrophages. Patients with this cytokine signature had a shorter (P= 0.017) Claudication Onset Distance (17 m) compared with patients lacking the signature (102 m). Transforming Growth Factor ß1 (TGFß1) and Chemokine Ligand 5 (CCL5) were expressed coordinately in all PAD and control muscles, independently of GM-CSF, IL-17A, IFN-ϒ, TNF-α, or IL-6. TGFß1 and CCL5 and their gene transcripts were increased in PAD muscle, consistent with increased age-associated inflammation in these patients. Serum cytokines were not informative of muscle cytokine expression. We have identified a cytokine profile of autoimmune inflammation in calf muscles of a significant proportion of claudicating PAD patients, in association with decreased limb function, and a second independent profile consistent with increased "inflammaging" in all PAD patients.


Asunto(s)
Citocinas/metabolismo , Inflamación/metabolismo , Claudicación Intermitente/metabolismo , Músculo Esquelético/metabolismo , Enfermedad Arterial Periférica/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Parasitol Res ; 119(12): 4073-4088, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33068148

RESUMEN

As a result of the experimental infection of rats with metacercariae of Paragonimus heterotremus Chen et Hsia, 1964 from crabs (Potamiscus tannanti) caught in Yen Bai province, Vietnam, it was found that worms migrated into the lungs, to the liver and less frequently to the tissue that lines body cavities of the hosts, where they reached the adult stage, but in the muscles, worms stayed at the larval stage. Studies have shown that for P. heterotremus, rats can simultaneously play the role of the final and paratenic host; herewith, an infection with the trematode of this species can lead to the development of three forms of paragonimiasis: pulmonary, hepatic and muscular. Eggs from the adult worms localised in the liver, unlike eggs from the adult worms localised in the lungs, were not excreted into the external environment, but accumulated inside the organ. Histology and description of changes, which take place on the external surface of organs affected with P. heterotremus, are given in this study. Based on the behavioural characteristics of worms during rat infection and molecular genetic data, we established that worms from Vietnam and India should be assigned to different species of Paragonimus. P. heterotremus distribution is limited to the territory of the Southeast China, Northern Vietnam, Laos and Thailand.


Asunto(s)
Hígado/parasitología , Pulmón/parasitología , Músculos/parasitología , Paragonimiasis/patología , Paragonimus/clasificación , Animales , Braquiuros/parasitología , China , India , Laos , Metacercarias/patogenicidad , Paragonimus/genética , Paragonimus/patogenicidad , Ratas , Tailandia , Vietnam
9.
Brain ; 143(6): 1843-1856, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32372102

RESUMEN

Recently, age-related timing dissociation between the superficial and deep venous systems has been observed; this was particularly pronounced in patients with normal pressure hydrocephalus, suggesting a common mechanism of ventriculomegaly. Establishing the relationship between venous drainage and ventricular enlargement would be clinically relevant and could provide insight into the mechanisms underlying brain ageing. To investigate a possible link between venous drainage and ventriculomegaly in both normal ageing and pathological conditions, we compared 225 healthy subjects (137 males and 88 females) and 71 traumatic brain injury patients of varying ages (53 males and 18 females) using MRI-based volumetry and a novel perfusion-timing analysis. Volumetry, focusing on the CSF space, revealed that the sulcal space and ventricular size presented different lifespan profiles with age; the latter presented a quadratic, rather than linear, pattern of increase. The venous timing shift slightly preceded this change, supporting a role for venous drainage in ventriculomegaly. In traumatic brain injury, a small but significant disease effect, similar to idiopathic normal pressure hydrocephalus, was found in venous timing, but it tended to decrease with age at injury, suggesting an overlapping mechanism with normal ageing. Structural bias due to, or a direct causative role of ventriculomegaly was unlikely to play a dominant role, because of the low correlation between venous timing and ventricular size after adjustment for age in both patients and controls. Since post-traumatic hydrocephalus can be asymptomatic and occasionally overlooked, the observation suggested a link between venous drainage and CSF accumulation. Thus, hydrocephalus, involving venous insufficiency, may be a part of normal ageing, can be detected non-invasively, and is potentially treatable. Further investigation into the clinical application of this new marker of venous function is therefore warranted.


Asunto(s)
Envejecimiento/patología , Lesiones Traumáticas del Encéfalo/metabolismo , Hidrocefalia/metabolismo , Adulto , Anciano , Envejecimiento/fisiología , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/fisiopatología , Ventrículos Cerebrales/patología , Femenino , Vena Femoral , Humanos , Hidrocefalia/etiología , Hidrocefalia/fisiopatología , Hidrocéfalo Normotenso/diagnóstico por imagen , Hidrocéfalo Normotenso/patología , Vena Ilíaca , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Malformaciones del Sistema Nervioso/patología , Vena Poplítea , Tomografía Computarizada por Rayos X/métodos
10.
Respir Med Case Rep ; 30: 101089, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32461883

RESUMEN

Chronic obstructive pulmonary disease (COPD) exacerbation and allergic bronchopulmonary aspergillosis (ABPA), in spite of sharing common features such as airway inflammation, airflow obstruction, and mucus hypersecretion, differ significantly from each other. We report a case of ABPA that was unsuccessfully treated as a COPD exacerbation. The history of non-exertional progressive dyspnea, absence of a symptom-free interval, and hemoptysis combined with a minimal, distant smoking history and prior employment at a fertilizer plant favor a diagnosis other than COPD exacerbation. The patient's disease progression and delay in diagnosis testify to the sway of cognitive biases. This case serves as a reminder that generating a thorough differential diagnosis early in a patient's care prevents misdiagnoses and hastens the initiation of definitive therapy.

11.
Sensors (Basel) ; 20(3)2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32046172

RESUMEN

Security performance and the impact of imperfect channel state information (CSI) in underlay cooperative cognitive networks (UCCN) is investigated in this paper. In the proposed scheme, relay R uses non-orthogonal multiple access (NOMA) technology to transfer messages e 1 , e 2 from the source node S to User 1 (U 1 ) and User 2 (U 2 ), respectively. An eavesdropper (E) is also proposed to wiretap the messages of U 1 and U 2 . The transmission's security performance in the proposed system was analyzed and performed over Rayleigh fading channels. Through numerical analysis, the results showed that the proposed system's secrecy performance became more efficient when the eavesdropper node E was farther away from the source node S and the intermediate cooperative relay R. The secrecy performance of U 1 was also compared to the secrecy performance of U 2 . Finally, the simulation results matched the Monte Carlo simulations well.

12.
Parasitol Res ; 118(2): 469-481, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30623234

RESUMEN

Data on the life cycles and morphology of the developmental stages of Notocotylus magniovatus, Catatropis vietnamensis n. sp., and Pseudocatatropis dvoryadkini n. sp. were obtained. The Pseudocatatropis genus was restored based on our results. For the studied trematodes, the snails Parajuga spp., Helicorbis sujfunensis (Russia), and Melanoides tuberculata (Vietnam) serve as first intermediate hosts. It has been established that C. vietnamensis n. sp. differs from Catatropis harwoodi and Catatropis pakistanensis in the length of the ridge and metraterm and the location of the anterior papillae. In the life cycle of P. dvoryadkini n. sp., as in Pseudocatatropis joyeuxi, cercariae do not leave the first intermediate host. Both species are very similar in morphometric features, despite the fact that they share no common first intermediate hosts in their life cycles, and the areas of the European and Asian populations of flukes do not overlap. In phylogenetic trees and genetic distances based on the nucleotide sequences of the 28S gene and the ITS2 region of ribosomal DNA, Notocotylus attenuatus, Notocotylus intestinalis, and Notocotylus magniovatus are combined into one systematic group, while C. vietnamensis n. sp. and Catatropis indicus form another group. A third group includes members of different genera: P. dvoryadkini n. sp., and Notocotylus malhamensis, as well as three unclassified Notocotylus spp. The presence in the last group of flukes with three rows of papillae and a median ridge and lateral papillae indicates that these systematic criteria are not determinant in establishing membership of the parasitic worms to one or another genus of Notocotylidae.


Asunto(s)
Estadios del Ciclo de Vida , Filogenia , Caracoles/parasitología , Trematodos/clasificación , Trematodos/crecimiento & desarrollo , Animales , ADN Espaciador Ribosómico/genética , ARN Ribosómico 28S/genética , Federación de Rusia , Trematodos/anatomía & histología , Trematodos/genética , Vietnam
13.
Ann Vasc Surg ; 55: 112-121, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30114505

RESUMEN

BACKGROUND: Claudication is the most common manifestation of peripheral artery disease (PAD), producing significant ambulatory compromise. Limited information exists on the routine physical activity of claudicating patients. Our objective was to record the intensity/time profiles of physical activity and the timing and duration of sedentary behavior of a sample of community-dwelling claudicating patients. METHODS: Forty-four claudicating patients referred to our vascular clinic were recruited. Physical activity was recorded using the ActiGraph GT1M activity monitor. The Actigraph monitor is a lightweight instrument designed to measure human movement through changes in acceleration, measured as counts over 1-minute time periods. Data from 7 consecutive days were used for the calculations. We processed the data using the ActiLife software program. RESULTS: The average daily activity of the claudicating patients shows a steady increase beginning approximately 05:30 AM until a peak plateau from approximately 10:00 AM to 01:30 PM followed by a steady decrease until approximately 09:30 PM, when a sustained period of inactivity begins. The average claudicating patient takes 3586 steps per day at an average intensity of 1.77 metabolic equivalents of task (METs, a physiological measure expressing the energy cost of physical activities). Average physical activity intensity and peak intensity fluctuate very little during the day, and they rarely exceed the level of light activity (light = <3 METs maximum effort, such as casual walking or light housework). During awake time, approximately 7 hours are spent in sedentary behaviors (<1.5 METs), and sedentary time is spread throughout the day mostly in short intervals between periods of low-energy activity. CONCLUSIONS: Our study objectively demonstrates the reduced physical activity of claudicating patients and documents physical activity/duration profiles throughout the day. The intensity of the physical activity of the average claudicating patient fluctuates very little during the day and rarely exceeds a light intensity level. Claudicating patients spend approximately half of their awake time in sedentary behavior and when they walk they do it in short bursts followed by several minutes of rest. We anticipate that changes in routine physical activity/duration profiles of patients with PAD will provide relevant, sensitive, and direct measures of the effectiveness of therapeutic interventions.


Asunto(s)
Ciclos de Actividad , Ejercicio Físico , Conductas Relacionadas con la Salud , Claudicación Intermitente/fisiopatología , Claudicación Intermitente/psicología , Enfermedad Arterial Periférica/fisiopatología , Enfermedad Arterial Periférica/psicología , Conducta Sedentaria , Actigrafía/instrumentación , Anciano , Femenino , Monitores de Ejercicio , Humanos , Claudicación Intermitente/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico , Factores de Tiempo
14.
Sensors (Basel) ; 18(11)2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30423919

RESUMEN

In this research, we investigate a hybrid time-switching relay (TSR)⁻power-splitting relay (PSR) alternate energy harvesting (EH) relaying network over the Rician fading channels. For this purpose, the amplify-and-forward (AF) mode is considered for the alternative hybrid time TSR⁻PSR. The system model consists of one source, one destination and two alternative relays for signal transmission from the source to the destination. In the first step, the exact and asymptotic expressions of the outage probability and the symbol errors ratio (SER) are derived. Then, the influence of all system parameters on the system performance is investigated, and the Monte Carlo simulation verifies all results. Finally, the system performances of TSR⁻PSR, TSR, and PSR cases are compared in connection with all system parameters.

15.
Parasite ; 25: 35, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30040609

RESUMEN

Males of Cathayacanthus spinitruncatus Amin, Heckmann & Ha, 2014 (Rhadinorhynchinae Lühe, 1912) are described for the first time from Leiognathus equulus in Hai Phong and Nha Trang and from pony fish Nuchequula flavaxilla in Quang Ninh in the Pacific waters of Vietnam. The male allotype status is designated. Males of C. spinitruncatus are smaller and have fewer and smaller proboscis hooks and trunk spines than females. The male reproductive structures are in the posterior fifth of the trunk and with 6 club-shaped cement glands gradually merging into 6 independent cement gland ducts. The proboscis receptacle is more than half as long as the trunk and with a cephalic ganglion at its anterior end. In females, the receptacle is only about one fifth the length of the trunk. Specimens described as Cathayacanthus bagarii Moravec & Sey, 1989 were shown to have been wrongly assigned to Cathayacanthus. Pararhadinorhynchus magnus n. sp. (Diplosentidae) is described from Scatophagus argus off Hai Phong in the Gulf of Tonkin. It is the third species of the genus and is readily distinguished from the Australian species by having a considerably larger trunk and male reproductive structures, and more proboscis hooks. X-ray microanalysis (EDAX) of intact and gallium-cut hooks of P. magnus showed high calcium and phosphate mainly in the central core. Specimens of Heterosentis holospinus Amin, Heckmann & Ha, 2011 (Arhythmacanthidae) are also reported from L. equulus off Quang Binh, new host and locality records.


Asunto(s)
Acantocéfalos/aislamiento & purificación , Enfermedades de los Peces/epidemiología , Peces/parasitología , Helmintiasis Animal/epidemiología , Acantocéfalos/anatomía & histología , Acantocéfalos/ultraestructura , Animales , Organismos Acuáticos , Australia/epidemiología , Microanálisis por Sonda Electrónica , Femenino , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , Masculino , Microscopía Electrónica de Rastreo , Reproducción , Vietnam/epidemiología
16.
J Transl Med ; 14: 39, 2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26847457

RESUMEN

BACKGROUND: Lower leg ischemia, myopathy, and limb dysfunction are distinguishing features of peripheral artery disease (PAD). The myopathy of PAD is characterized by myofiber degeneration in association with extracellular matrix expansion, and increased expression of transforming growth factor-beta 1 (TGF-ß1; a pro-fibrotic cytokine). In this study, we evaluated cellular expression of TGF-ß1 in gastrocnemius of control (CTRL) and PAD patients and its relationship to deposited collagen, fibroblast accumulation and limb hemodynamics. METHODS: Gastrocnemius biopsies were collected from PAD patients with claudication (PAD-II; N = 25) and tissue loss (PAD-IV; N = 20) and from CTRL patients (N = 20). TGF-ß1 in slide-mounted specimens was labeled with fluorescent antibodies and analyzed by quantitative wide-field, fluorescence microscopy. We evaluated co-localization of TGF-ß1 with vascular smooth muscle cells (SMC) (high molecular weight caldesmon), fibroblasts (TE-7 antigen), macrophages (CD163), T cells (CD3) and endothelial cells (CD31). Collagen was stained with Masson Trichrome and collagen density was determined by quantitative bright-field microscopy with multi-spectral imaging. RESULTS: Collagen density increased from CTRL to PAD-II to PAD-IV specimens (all differences p < 0.05) and was prominent around microvessels. TGF-ß1 expression increased with advancing disease (all differences p < 0.05), correlated with collagen density across all specimens (r = 0.864; p < 0.001), associated with fibroblast accumulation, and was observed exclusively in SMC. TGF-ß1 expression inversely correlated with ankle-brachial index across PAD patients (r = -0.698; p < 0.001). CONCLUSIONS: Our findings support a progressive fibrosis in the gastrocnemius of PAD patients that is caused by elevated TGF-ß1 production in the SMC of microvessels in response to tissue hypoxia.


Asunto(s)
Músculo Esquelético/patología , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Enfermedad Arterial Periférica/patología , Factor de Crecimiento Transformador beta1/metabolismo , Estudios de Casos y Controles , Colágeno/metabolismo , Demografía , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Fibrosis , Humanos , Masculino , Microvasos/metabolismo , Microvasos/patología , Persona de Mediana Edad
17.
J Surg Res ; 196(1): 172-9, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25791828

RESUMEN

BACKGROUND: Peripheral artery disease (PAD), which affects an estimated 27 million people in Europe and North America, is caused by atherosclerotic plaques that limit blood flow to the legs. Chronic, repeated ischemia in the lower leg muscles of PAD patients is associated with loss of normal myofiber morphology and myofiber degradation. In this study, we tested the hypothesis that myofiber morphometrics of PAD calf muscle are significantly different from normal calf muscle and correlate with reduced calf muscle strength and walking performance. METHODS: Gastrocnemius biopsies were collected from 154 PAD patients (Fontaine stage II) and 85 control subjects. Morphometric parameters of gastrocnemius fibers were determined and evaluated for associations with walking distances and calf muscle strength. RESULTS: Compared with control myofibers, PAD myofiber cross-sectional area, major and minor axes, equivalent diameter, perimeter, solidity, and density were significantly decreased (P < 0.005), whereas roundness was significantly increased (P < 0.005). Myofiber morphometric parameters correlated with walking distances and calf muscle strength. Multiple regression analyses demonstrated myofiber cross-sectional area, roundness, and solidity as the best predictors of calf muscle strength and 6-min walking distance, whereas cross-sectional area was the main predictor of maximum walking distance. CONCLUSIONS: Myofiber morphometrics of PAD gastrocnemius differ significantly from those of control muscle and predict calf muscle strength and walking distances of the PAD patients. Morphometric parameters of gastrocnemius myofibers may serve as objective criteria for diagnosis, staging, and treatment of PAD.


Asunto(s)
Extremidades/fisiopatología , Claudicación Intermitente/patología , Fibras Musculares Esqueléticas/patología , Anciano , Femenino , Humanos , Claudicación Intermitente/fisiopatología , Masculino , Persona de Mediana Edad , Fuerza Muscular
18.
J Histochem Cytochem ; 63(4): 256-69, 2015 04.
Artículo en Inglés | MEDLINE | ID: mdl-25575565

RESUMEN

Patients with peripheral artery disease (PAD) develop a myopathy in their ischemic lower extremities, which is characterized by myofiber degeneration, mitochondrial dysfunction and impaired limb function. Desmin, a protein of the cytoskeleton, is central to maintenance of the structure, shape and function of the myofiber and its organelles, especially the mitochondria, and to translation of sarcomere contraction into muscle contraction. In this study, we investigated the hypothesis that disruption of the desmin network occurs in gastrocnemius myofibers of PAD patients and correlates with altered myofiber morphology, mitochondrial dysfunction, and impaired limb function. Using fluorescence microscopy, we evaluated desmin organization and quantified myofiber content in the gastrocnemius of PAD and control patients. Desmin was highly disorganized in PAD but not control muscles and myofiber content was increased significantly in PAD compared to control muscles. By qPCR, we found that desmin gene transcripts were increased in the gastrocnemius of PAD patients as compared with control patients. Increased desmin and desmin gene transcripts in PAD muscles correlated with altered myofiber morphology, decreased mitochondrial respiration, reduced calf muscle strength and decreased walking performance. In conclusion, our studies identified disruption of the desmin system in gastrocnemius myofibers as an index of the myopathy and limitation of muscle function in patients with PAD.


Asunto(s)
Desmina/metabolismo , Mitocondrias/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Enfermedad Arterial Periférica/metabolismo , Anciano , Estudios de Casos y Controles , Recuento de Células , Humanos , Extremidad Inferior , Persona de Mediana Edad , Fibras Musculares Esqueléticas/patología , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Enfermedad Arterial Periférica/patología , Enfermedad Arterial Periférica/fisiopatología , Caminata
19.
Redox Biol ; 2: 921-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25180168

RESUMEN

BACKGROUND: Peripheral artery disease (PAD), a manifestation of systemic atherosclerosis that produces blockages in the arteries supplying the legs, affects approximately 5% of Americans. We have previously, demonstrated that a myopathy characterized by myofiber oxidative damage and degeneration is central to PAD pathophysiology. OBJECTIVES: In this study, we hypothesized that increased oxidative damage in the myofibers of the gastrocnemius of PAD patients is myofiber-type selective and correlates with reduced myofiber size. METHODS: Needle biopsies were taken from the gastrocnemius of 53 PAD patients (28 with early PAD and 25 with advanced PAD) and 25 controls. Carbonyl groups (marker of oxidative damage), were quantified in myofibers of slide-mounted tissue, by quantitative fluorescence microscopy. Myofiber cross-sectional area was determined from sarcolemma labeled with wheat germ agglutinin. The tissues were also labeled for myosin I and II, permitting quantification of oxidative damage to and relative frequency of the different myofiber Types (Type I, Type II and mixed Type I/II myofibers). We compared PAD patients in early (N=28) vs. advanced (N=25) disease stage for selective, myofiber oxidative damage and altered morphometrics. RESULTS: The carbonyl content of gastrocnemius myofibers was higher in PAD patients compared to control subjects, for all three myofiber types (p<0.05). In PAD patients carbonyl content was higher (p<0.05) in Type II and I/II fibers compared to Type I fibers. Furthermore, the relative frequency and cross-sectional area of Type II fibers were lower, while the relative frequencies and cross-sectional area of Type I and Type I/II fibers were higher, in PAD compared to control gastrocnemius (p<0.05). Lastly, the type II-selective oxidative damage increased and myofiber size decreased as the disease progressed from the early to advanced stage. CONCLUSIONS: Our data confirm increased myofiber oxidative damage and reduced myofiber size in PAD gastrocnemius and demonstrate that the damage is selective for type II myofibers and is worse in the most advanced stage of PAD.


Asunto(s)
Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Estrés Oxidativo , Enfermedad Arterial Periférica/metabolismo , Enfermedad Arterial Periférica/patología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Int J Parasitol ; 44(11): 795-810, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25123068

RESUMEN

Clonorchiasis is a parasitic disease of high public health importance in many countries in southeastern Asia and is caused by the Chinese liver fluke Clonorchis sinensis. However, the genetic structure and demographic history of its populations has not been sufficiently studied throughout the geographic range of the species and available data are based mainly on partial gene sequencing. In this study, we explored the genetic diversity of the complete 1560 bp cytochrome c oxidase subunit 1 (cox1) gene sequence for geographically isolated C. sinensis populations in Russia and Vietnam, to our knowledge for the first time. The results demonstrated low nucleotide and high haplotype differentiation within and between the two compared regions and a clear geographical vector for the distribution of genetic diversity patterns among the studied populations. These results suggest a deep local adaptation of the parasite to its environment including intermediate hosts and the existence of gene flow across the species' range. Additionally, we have predicted an amino acid substitution in the functional site of the COX1 protein among the Vietnamese populations, which were reported to be difficult to treat with praziquantel. The haplotype networks consisted of several region-specific phylogenetic lineages, the formation of which could have occurred during the most extensive penultimate glaciations in the Pleistocene Epoch. The patterns of genetic diversity and demographics are consistent with population growth of the liver fluke in the late Pleistocene following the Last Glacial Maximum, indicating the lack of a population bottleneck during the recent past in the species' history. The data obtained have important implications for understanding the phylogeography of C. sinensis, its host-parasite interactions, the ability of this parasite to evolve drug resistance, and the epidemiology of clonorchiasis under global climate change.


Asunto(s)
Clonorquiasis/parasitología , Clonorchis sinensis/genética , Variación Genética , Animales , Secuencia de Bases , Clonorquiasis/epidemiología , ADN de Helmintos/genética , Masculino , Filogenia , Ratas , Ratas Sprague-Dawley , Federación de Rusia/epidemiología , Vietnam/epidemiología
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