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1.
S. Afr. j. child health ; 16(3): 146-156, 2022. figures, tables
Artículo en Inglés | AIM (África) | ID: biblio-1397943

RESUMEN

Background. Road traffic accidents (RTAs) are a leading cause of injury and death globally, particularly among children. Pedestrians are most often injured, especially in middle- and low-income countries. The epidemiology, patterns and severity of injuries in children involved in RTAs in our community are hard to obtain. Objectives. To evaluate the aetiological spectrum, injury characteristics and treatment outcomes of paediatric patients involved in RTAs,who presented to Chris Hani Baragwanath Academic Hospital (CHBAH), a tertiary hospital in Soweto, South Africa. Methods. Patients ≤10 years old, who were involved in RTAs and seen at CHBAH, were included in the study. Results. The study was conducted from 20 August 2017 to 31 March 2018, and included the data of 156 patients. Their ages ranged from 13 days to 10 years (65% were boys). Pedestrian vehicle accidents accounted for 78.8% of the injuries, with 60.8% of the children being unaccompanied by an adult. Motor vehicle accidents accounted for 19.2% of the injuries, with 92% of the children being unrestrained in the vehicle. Of the patients, 73.2% (n=112/153) underwent radiography and 44.4% required computed tomography (CT) scans, the majority being CT scans of the brain for suspected head injuries. Soft-tissue injuries accounted for 78.9% of cases, followed mainly by head (39.7%) and limb (16%) injuries. Only 12% of patients required surgical intervention, with 42% of the operations being for orthopaedic injuries. Conclusion. The abovementioned data demonstrate that there is a lack of use of child restraints for children travelling as passengers invehicles, and inadequate supervision of children on and around roads. This study supports other evidence, as it suggests that the paediatric population involved in RTAs is largely injured as pedestrians, and that males tend to be involved in more RTAs than females. The majority of injuries sustained involved the soft tissues, followed by head injuries


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Heridas y Lesiones , Accidentes de Tránsito , Tomografía Computarizada por Rayos X , Epidemiología
2.
Rheumatol Int ; 41(6): 1089-1096, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32797279

RESUMEN

Objective methods are needed to quantify digital artery disease in systemic sclerosis (SSc) for clinical trials of vascular therapies. Our primary aim was to examine feasibility of a novel tomographic three-dimensional-(3-D) ultrasound (tUS) with high-frequency ultrasound (HFUS) or ultra-high-frequency ultrasound (UHFUS) to assess the digital arteries in patients with SSc compared to healthy controls. A secondary objective was to compare the total wall volume (TWV) as a measure of intimal/medial thickness. Eighteen patients with a confirmed diagnosis of SSc were studied by tUS HFUS (17.5 MHz, n = 10) or tUS UHFUS (48 and 70 MHz, n = 8) with equal numbers of healthy controls of similar age and gender. The majority of patients had limited cutaneous SSc and were representative of a spectrum of digital vasculopathy, with over half (n = 6 HFUS and n = 5 UHFUS) having previous digital ulceration. Over half were receiving oral vasodilatory therapy. TWV was measured in both digital arteries of the middle finger bilaterally. At least, two digital arteries could be identified at 17.5 MHz in all patients and healthy controls. Whereas, at least two digital arteries could be identified in relatively fewer patients compared to healthy controls using 48 MHz (n = 6 and 10) and especially 70 MHz (n = 4 and 10) UHFUS. The median difference in TWV between patients and healthy controls was -6.49 mm3 using 17.5 MHz, 1.9 mm3 at 48 MHz, and -0.4 mm3 at 70 MHz. tUS using UHFUS is a feasible method to measure TWV of digital arteries in SSc. Transducer frequency plays an important factor in successful digital artery measurement, with 48 MHz being the optimal frequency.


Asunto(s)
Arterias/diagnóstico por imagen , Dedos/irrigación sanguínea , Esclerodermia Sistémica/complicaciones , Anciano , Estudios de Casos y Controles , Estudios Transversales , Femenino , Dedos/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Esclerodermia Sistémica/fisiopatología , Tomografía Computarizada por Rayos X , Ultrasonografía
3.
Neotrop Entomol ; 49(5): 685-695, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32720063

RESUMEN

The endangered butterfly Scada karschina delicata Talbot, 1932 (Nymphalidae: Danainae: Ithomiini) is endemic to northeastern Brazil, occurring in very few forest remnants of the 'Pernambuco Center of Endemism'. Larvae feed on Solanaceae and are very similar to those of other species in the subtribe Mechanitina, with lateral projections on body, one of the main synapomorphies of this subtribe. Based on molecular data, S. k. delicata clustered together with S. karschina karschina, as a monophyletic group sister to the amazon clade of S. reckia. Based on all available data, S. k. delicata is known from only five localities of mid- to high-altitude forests (from 500 to 1000 m of altitude) in northeastern Brazil. Grounded on available data, a new assessment of extinction risk is proposed, and S. k. delicata is now considered Vulnerable (VU) taxon.


Asunto(s)
Mariposas Diurnas/fisiología , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Filogenia , Distribución Animal , Animales , Brasil , Mariposas Diurnas/clasificación , Ecosistema , Bosques , Estadios del Ciclo de Vida , Solanaceae
4.
Opt Express ; 28(8): 12149-12156, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32403714

RESUMEN

Full-color smart displays, which act both as a display and as a high-speed visible light communication (VLC) transmitter, can be realized by the integration of red-green-blue micron-sized light emitting diodes (micro-LEDs) onto a common platform. In this work, we report on the integration of aluminum gallium indium phosphide red micro-LEDs onto diamond and glass substrates by micro-transfer printing and their application in VLC. The device on-diamond exhibits high current density and bandwidth operation, enabled by diamond's superior thermal properties. Employing an orthogonal frequency division multiplexing modulation scheme, error-free data rates of 2.6 Gbps and 5 Gbps are demonstrated for a single micro-LED printed on-glass and on-diamond, respectively. In a parallel configuration, a 2x1 micro-LED array achieves error-free data rates of 3 Gbps and 6.6 Gbps, on-glass and on-diamond, respectively.

5.
Opt Express ; 28(5): 6909-6917, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32225928

RESUMEN

We present integration of singulated micron-sized light emitting diodes (micro-LEDs) directly onto a silicon CMOS drive chip using a transfer printing method. An 8x8 micro-LED device array with individual control over each pixel is demonstrated with modulation bandwidths up to 50 MHz, limited by the large modulation depth of the driver chip. The 2 kHz frame rate CMOS driver also incorporates a Single Photon Avalanche Diode device thus allowing detection and transmission functionality on a single integrated chip. Visible light communications at data rates up to 1 Mbps, and time-of-flight ranging with cm-scale resolution are demonstrated using this hybrid integrated system.

6.
Opt Express ; 27(20): A1517-A1528, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31684503

RESUMEN

Integrated multi-color micron-sized light emitting diode (micro-LED) arrays have been demonstrated in recent years for display applications; however, their potential as visible light communication (VLC) transmitters is yet to be fully explored. In this work, we report on the fabrication and characterization of on-chip dual-color micro-LED arrays and their application in VLC. For this purpose, blue-green and blue-violet micro-LED arrays were fabricated by transfer printing blue-emitting micro-LEDs onto the substrate of green and violet micro-LEDs, respectively. The potential of these dual-color micro-LED arrays as VLC transmitters is demonstrated with respective error-free data rates of 1.79 and 3.35 Gbps, achieved by the blue-green and blue-violet devices in a dual wavelength multiplexing scheme.

7.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29605558

RESUMEN

OBJECTIVE: Computer-assisted surgery application in total knee arthroplasty (TKA) has shown more accurate implant alignment compared with conventional instrumentation and is associated with more homogeneous alignment results. Although longer implant survival and superior clinical outcomes should be expected from navigated TKA, currently available evidence does not support this hypothesis. The aim of this study was to compare navigated TKA with conventional TKA regarding clinical and radiological outcomes after a 3-year follow-up under the hypothesis that navigated TKA would provide better outcomes than conventional TKA. MATERIAL AND METHOD: In a prospective multicentre study, 119 patients underwent navigated TKA and 80 patients received conventional instrumentation. Patients were evaluated at the baseline and at postoperative months 3, 12, 24, and 36. Analysis included the American Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form-12 (SF12) Health Survey, and radiographic assessment. RESULTS: All clinical scores improved significantly for all patients during the follow-up but were significantly better in the navigation group. The percentage of patients showing a mechanical axis between 3° of varus and 3° of valgus was significantly higher in the ATR group (93%) than in the conventional TKA group (71%) (P<.01). CONCLUSIONS: The use of computer-assisted surgery in TKA provides more accurate mechanical alignment and superior short-term functional outcomes compared to conventional TKA.

8.
Opt Express ; 26(24): 31474-31483, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30650732

RESUMEN

Visible light communications (VLC) is an emerging technology that uses LEDs, such as found in lighting fixtures and displays, to transmit data wirelessly. Research has so far focused on LED transmitters and on photoreceivers as separate, discrete components. Combining both types of devices into a single transceiver format will enable bi-directional VLC and offer flexibility for the development of future advanced VLC systems. Here, a proof of concept for an integrated optical transceiver is demonstrated by transfer printing a microsize LED, the transmitter, directly onto a fluorescent optical concentrator edge-coupled to a photodiode, the receiver. This integrated device can simultaneously receive (downlink) and transmit (uplink) data at rates of 416 Mbps and 165 Mbps, respectively. Its capability to operate in optical relay mode at 337 Mbps is experimentally demonstrated.

9.
Ir J Med Sci ; 187(1): 155-161, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28593573

RESUMEN

OBJECTIVE: The aim of our study is to analyse hospital readmissions due to asthma, as well as the factors associated with their increase. STUDY DESIGN: We carried out a retrospective study including all admissions of patients over 18 years old due to exacerbation of asthma occurring in our hospital between the years 2000 and 2010. METHODS: The data were gathered by two members of the research team, by reviewing the clinical records. The first hospital admission of each patient was included for this study. An early readmission (ER) was defined as that which occurred in the following 15 days after hospital discharge and late readmission (LR) to that occurring from 16 days after discharge. RESULTS: This study included 2166 hospital admissions and 1316 patients, with a mean age of 62.6 years. Of the 1316 patients analysed, 36 (2.7%) had one ER and 313 (23.8%) one LR. The only factor independently associated with a higher probability of an ER was poor lung function. A higher probability of LR was associated with a greater severity of the asthma (OR: 17.8, for severe asthma versus intermittent asthma), to have had any hospital admission in the previous year (OR: 3.5) and the use of a combination of ICS-LABA as maintenance treatment. CONCLUSIONS: About 25% of the patients in our area admitted to hospital due to asthma exacerbation had repeat episodes of hospitalisation.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Hospitalización/tendencias , Readmisión del Paciente/tendencias , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
10.
Rev Esp Cir Ortop Traumatol ; 61(5): 313-318, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28684111

RESUMEN

OBJECTIVE: To establish the concordance between angulation of the femoro-tibial mechanical axis measured with x-rays and surgical navigation in both the pre and postoperative period after a total knee arthroplasty (TKA) was implanted. MATERIAL AND METHOD: Pre and postoperative measurements were analyzed in 88 TKA of the same model and all performed with the same surgical navigation system. The mechanical frontal angle (MFA) and femoro-tibial anatomic angle were measured before and after the TKA. The angulation was digitally measured with a teleradiography. In the navigation, the femoro-tibial angle at rest, forced varus and valgus were registered and the average of these three measurements was calculated. RESULTS: The mean preoperative MFA measured on the radiograph was 4.55°. The mean of the same angle measured on the postoperative radiograph was 1.72°, (p=0.05). The mean of the MFA measured with navigation before TKA was 3.12° and after the implant with navigation was 0.53 (P=.013). The concordance coefficient between the MFA in teleradiography and in navigation was 0.869 (P<.001) preoperatively and 0.709 postoperatively (P=.017). CONCLUSIONS: We found a strong concordance between radiographic and surgical navigation measurements of the MFA. This may imply that teleradiography is not necessary when using surgical navigation in TKA.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/fisiología , Cirugía Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Masculino , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Prospectivos , Radiografía , Torsión Mecánica
11.
Basic Clin Androl ; 27: 12, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28649382

RESUMEN

BACKGROUND: In humans, it is now well documented that rising paternal age is correlated with decreased sperm DNA integrity and embryonic developmental failures. On the other side of the coin, it is also reported that very young fathers such as teenagers carry an increased risk of adverse birth outcomes. These observations suggest that, at least in humans, there is an age window for optimal sperm DNA integrity. In bovine, little is known about sperm DNA quality in young bulls and how it evolves with age. This study aimed to fill in this gap as it may be of importance for the bovine industry to know when exactly a bull is an optimal performer for reproductive programs. METHODS: Forty Nellore bulls were divided into three age groups: 1.8 to 2 years - young bulls; 3.5 to 7 years - adult bulls; and 8 to 14.3 years - aged bulls. Three ejaculates were collected from each bull, cryopreserved and evaluated for various parameters including: computer-assisted sperm analysis (CASA), plasma membrane and acrosome integrity, mitochondrial potential, sperm nuclear protamination, DNA oxidative damage, and Sperm Chromatin Structure Assay (SCSA). RESULTS: We report here that young bulls presented superior values for motility, plasma and acrosomal membrane integrity, and high mitochondrial potential. However, they also presented higher values for sperm morphological abnormalities compared to adult and aged animal groups (p < 0.05). In addition, young bulls exhibited more defective protamination than older animals did. The oldest bulls showed more nuclear oxidative damage than the younger groups of bulls while both the young and aged groups were found more susceptible to DNA denaturation as revealed with the SCSA test (p < 0.05). CONCLUSION: These results indicate that young bulls spermatozoa best survived the freezing procedure, followed by adult and aged bulls. However, young and aged bulls were found to be more susceptible to DNA damage, respectively caused by protamine deficiency and oxidation. Therefore, although young bulls have correct semen parameters according to classical evaluation, our results indicate that they may show some structural nuclear immaturity.


CONTEXTE: Chez l'homme, de nombreuses données indiquent maintenant que l'avancée de l'âge du père est associée à une réduction de l'intégrité de l'ADN des spermatozoïdes et aux échecs de développement embryonnaire. D'un autre côté, il est aussi rapporté que les jeunes pères, tels les adolescents, sont porteurs d'un risque accru d'issue défavorable de la grossesse. Ces observations suggèrent que, au moins chez l'humain, il existe une tranche d'âge dans laquelle l'intégrité de l'ADN des spermatozoïdes est optimale. Chez les bovins, on dispose de peu de connaissances sur la qualité de l'ADN des spermatozoïdes des jeunes taureaux et sur son mode d'évolution avec l'âge. La présente étude a pour but de combler ce manque car il peut être important, pour l'industrie bovine, de savoir à quelle période précise un taureau est un reproducteur optimal pour les programmes de reproduction. MATÉRIEL ET MÉTHODES: Quarante taureaux Nellore ont été répartis en trois groupes d'âge: 1, 8 à 2 ans ­ jeunes taureaux; 3,5 à 7 ans ­ taureaux adultes; et 8 à 14,3 ans ­ taureaux âgés. Trois éjaculats ont été collectés par taureau, cryopréservés et évalués pour différents paramètres incluant l'analyse assistée du sperme par ordinateur (CASA), l'intégrité des membranes plasmique et acrosomique, le potentiel mitochondrial, la protamination du noyau, l'altération oxydative de l'ADN et l'évaluation de la structure de la chromatine du noyau du spermatozoïde (SCSA). RÉSULTATS: Nous rapportons ici que les jeunes taureaux présentent des valeurs supérieures de la mobilité des spermatozoïdes et de l'intégrité des membranes plasmique et acrosomique, ainsi qu'un potentiel mitochondrial élevé. Cependant, les jeunes taureaux présentent aussi des valeurs plus élevées d'anomalies morphologiques des spermatozoïdes que celles des groupes adulte et âgé (p < 0.05). De plus, les jeunes taureaux ont une protamination plus défectueuse que celle des taureaux plus âgés. Les taureaux les plus âgés présentent plus d'altérations oxydatives du noyau que les jeunes taureaux alors que les deux groupes -jeunes et âgés- sont plus susceptibles d'avoir une dénaturation de l'ADN nucléaire comme indiqué par le SCSA (p < 0.05). CONCLUSIONS: Ces résultats indiquent que les spermatozoïdes des jeunes taureaux survivent le mieux au processus de congélation, suivis par les adultes puis les âgés. Toutefois, les jeunes taureaux et les âgés sont plus susceptibles d'avoir une altération de l'ADN, causée respectivement par une protamination déficiente et une oxydation. Par conséquent, bien que les jeunes taureaux aient des paramètres spermatiques corrects à l'évaluation classique, nos résultats indiquent que leurs spermatozoïdes peuvent présenter un certain degré d'immaturité structurale nucléaire.

12.
ACS Appl Mater Interfaces ; 9(4): 4084-4099, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28111948

RESUMEN

In this work, the exceptionally improved sensing capability of highly porous three-dimensional (3-D) hybrid ceramic networks toward reducing gases is demonstrated for the first time. The 3-D hybrid ceramic networks are based on doped metal oxides (MexOy and ZnxMe1-xOy, Me = Fe, Cu, Al) and alloyed zinc oxide tetrapods (ZnO-T) forming numerous junctions and heterojunctions. A change in morphology of the samples and formation of different complex microstructures is achieved by mixing the metallic (Fe, Cu, Al) microparticles with ZnO-T grown by the flame transport synthesis (FTS) in different weight ratios (ZnO-T:Me, e.g., 20:1) followed by subsequent thermal annealing in air. The gas sensing studies reveal the possibility to control and change/tune the selectivity of the materials, depending on the elemental content ratio and the type of added metal oxide in the 3-D ZnO-T hybrid networks. While pristine ZnO-T networks showed a good response to H2 gas, a change/tune in selectivity to ethanol vapor with a decrease in optimal operating temperature was observed in the networks hybridized with Fe-oxide and Cu-oxide. In the case of hybridization with ZnAl2O4, an improvement of H2 gas response (to ∼7.5) was reached at lower doping concentrations (20:1), whereas the increase in concentration of ZnAl2O4 (ZnO-T:Al, 10:1), the selectivity changes to methane CH4 gas (response is about 28). Selectivity tuning to different gases is attributed to the catalytic properties of the metal oxides after hybridization, while the gas sensitivity improvement is mainly associated with additional modulation of the electrical resistance by the built-in potential barriers between n-n and n-p heterojunctions, during adsorption and desorption of gaseous species. Density functional theory based calculations provided the mechanistic insights into the interactions between different hybrid networks and gas molecules to support the experimentally observed results. The studied networked materials and sensor structures performances would provide particular advantages in the field of fundamental research, applied physics studies, and industrial and ecological applications.

13.
Semergen ; 43(1): 4-12, 2017.
Artículo en Español | MEDLINE | ID: mdl-27165297

RESUMEN

INTRODUCTION: Non-compliance with antibiotics treatment has severe consequences. Although antibiotics are commonly prescribed drugs, there are few studies that evaluate therapeutic compliance in acute diseases. The main objective of this study is to determine the percentage of non-compliance with the systemic antibiotics treatment prescribed in emergency departments. MATERIAL AND METHODS: A prospective observational study was performed in the Emergency Department of 2 health centres of the Cantabria Health Service between the months of June and September 2014. The study included patients of any age, and those could be monitored, who were prescribed a systemic antibiotic for any infectious disease. Sociodemographic variables, diseases, and compliance were the variables studied. The Morinsky-Green test was used, plus 3 questions added by the authors. RESULTS: Of the 303 patients included, non-compliance, evaluated using the Morinsky-Green test, was 32.7% (95% CI 27.6-38.1), with this rising to the 44.9% (95% CI 39.4-50.5) when the 3 mentioned questions were added to the test. A downward trend is observed in non-compliance as the age increases. The risk of non-compliance is twice in men than in women: OR=2.02 (95% CI 1.27-3.24). CONCLUSIONS: Almost half (45%) of the patients who are prescribed antibiotics do not comply with the indications. Most of them attribute this fact to forgetfulness in compliance with the prescribed treatment. The elderly and women follow the treatment better, which should be taken into account when designing strategies to improve therapeutic compliance.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Bacterianas/tratamiento farmacológico , Servicio de Urgencia en Hospital , Cumplimiento de la Medicación/estadística & datos numéricos , Enfermedad Aguda , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atención Primaria de Salud , Estudios Prospectivos , Factores Sexuales , Adulto Joven
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 172: 163-167, 2017 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-27133357

RESUMEN

Rare earth orthosilicates are among the most widely used scintillator materials in the last decades. Particularly, lutetium-yttrium oxyorthosilicate (LYSO) is known to exhibit great potentialities in the field of radiation detectors for medical imaging. Consequently, an in-depth knowledge of the material properties is of utmost interest for the mentioned applications. In this work the spectroscopic properties of commercial cerium doped lutetium-yttrium oxyorthosilicate crystals (LYSO:Ce) were investigated by Raman spectroscopy, steady state photoluminescence, photoluminescence excitation and time resolved photoluminescence. Site selective excitation was used under steady state (325nm) and pulsed (266nm) conditions to separately investigate the temperature dependence of the 5d→4f Ce1 and Ce2 luminescence, allowing to establish the thermal quenching dependence of the Ce2 optical center. In the case of the Ce1 optical center, a luminescence quantum efficiency of 78% was obtained from 14K to room temperature with 266nm photon excitation.

15.
Theriogenology ; 87: 154-160, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27712828

RESUMEN

The aim of this study was to evaluate the chromatin packing and sperm head morphometry of cryopreserved semen of Nelore bulls (Bos taurus indicus) of different ages. Furthermore, the influence of the degree of chromatin compaction on in vitro embryo production (IVP) was investigated. Forty bulls were divided into three groups: young (1.8-2 years), adult (3.5-7 years), and senile (8-14.3 years). The ejaculates were frozen according to standards established by the Artificial Insemination Center located in the Southeast of Brazil. Toluidine blue staining was used for simultaneous evaluation of the sperm chromatin and sperm head morphometry. Chromomycin A3 (CMA3) was applied to analyze sperm protamination and IVP for embryonic development. Spermatozoa of young bulls presented higher values for area (A, pixels), perimeter (P, pixels), and width (W, pixels) compared to adults and senile (young: A = 1848.5 ± 119.79, P = 10.23 ± 0.29, and W = 1.95 ± 0.1; adults: A = 1672.9 ± 104.46, P = 9.86 ± 0.33, and W = 1.81 ± 0.06; senile: A = 1723.1 ± 124.41, P = 9.97 ± 0.33, and W = 1.83 ± 0.09; P < 0.0001) and showed higher protamination deficiency when analyzed by CMA3 (young: 1.57 ± 0.76; adults: 1.09 ± 0.63, and senile: 0.90 ± 0.59; P < 0.05). Likewise, variables of sperm head size (A, P, and W) and protamination assessed by CMA3 showed negative correlation with age and positive correlation with ellipticity, evaluated by toluidine blue method (P < 0.05). Sperm head area was larger in spermatozoa presenting chromatin instabilities than spermatozoa without chromatin alteration (P < 0.0001). There was no difference in IVP when using semen with larger or smaller portions of spermatozoa with chromatin instabilities, indicating that the proportion of sperm with abnormal chromatin compaction (4%-16.15%) did not interfere with early embryonic development. From our results, it can be concluded that sperm of young Nelore bulls have larger heads compared to adults and senile due to reduced protamine content when evaluated by CMA3 and higher proportion of major sperm defects assessed by differential interference contrast microscopy.


Asunto(s)
Envejecimiento/fisiología , Bovinos/fisiología , Cromatina/fisiología , Fertilización In Vitro/veterinaria , Espermatozoides/citología , Animales , Masculino , Espermatozoides/fisiología
16.
Basic Clin Androl ; 26: 17, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28031843

RESUMEN

Sperm cells are remarkably complex and highly specialized compared to somatic cells. Their function is to deliver to the oocyte the paternal genomic blueprint along with a pool of proteins and RNAs so a new generation can begin. Reproductive success, including optimal embryonic development and healthy offspring, greatly depends on the integrity of the sperm chromatin structure. It is now well documented that DNA damage in sperm is linked to reproductive failures both in natural and assisted conception (Assisted Reproductive Technologies [ART]). This manuscript reviews recent important findings concerning - the unusual organization of mammalian sperm chromatin and its impact on reproductive success when modified. This review is focused on sperm chromatin damage and their impact on embryonic development and transgenerational inheritance.


Les spermatozoïdes sont des cellules particulièrement complexes et très spécialisées comparées aux cellules somatiques. Leur rôle est de délivrer dans l'ovule le patrimoine génétique paternel ainsi qu'un lot de protéines et d'ARNs de façon à initier un nouvel individu. Le succès reproductif qui recouvre les aspects de développement embryonnaire harmonieux et de santé de la descendance repose en partie sur l'intégrité de la chromatine spermatique. Les dommages à l'ADN spermatique sont clairement associés aux échecs reproductifs que ce soit en reproduction naturelle et en procréation médicalement assistée (PMA). Cette revue présente les derniers développements concernant l'organisation très particulière de la chromatine spermatique et ses impacts sur le succès reproductif quand cette organisation est perturbée, en particulier sur le développement embryonnaire et les risques trangénérationnels.

17.
Arq. bras. med. vet. zootec ; 67(2): 417-423, Mar-Apr/2015. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: lil-747038

RESUMEN

The routine semen evaluation assessing sperm concentration, motility and morphology, does not identify subtle defects in sperm chromatin architecture. Bulls appear to have stable chromatin, with low levels of DNA fragmentation. However, the nature of fragmentation and its impact on fertility remain unclear and there are no detailed reports characterizing the DNA organization and damage in this species. The intensive genetic selection, the use of artificial insemination and in vitro embryo production associated to the cryopreservation process can contribute to the chromatin damage and highlights the importance of sperm DNA integrity for the success of these technologies. Frozen-thawed semen samples from three ejaculates from a Nellore bull showed high levels of morphological sperm abnormalities (55.8±5.1%), and were selected for complementary tests. Damage of acrosomal (76.9±8.9%) and plasma membranes (75.7±9.3%) as well as sperm DNA strand breaks (13.8±9.5%) and protamination deficiency (3.7±0.6%) were significantly higher compared to the values measured in the semen of five Nellore bulls with normospermia (24.3±3.3%; 24.5±6.1%; 0.6±0.5%; 0.4±0.6% for acrosome, plasma membrane, DNA breaks and protamine deficiency, respectively) (P<0.05). Motility and percentage of spermatozoa with low mitochondrial potential showed no differences between groups. This study shows how routine semen analyses (in this case morphology) may point to the length and complexity of sperm cell damage emphasizing the importance of sperm function testing.(AU)


O exame de rotina de sêmen, o qual avalia a concentração de espermatozoides, a motilidade e a morfologia, pode não identificar defeitos sutis na arquitetura da cromatina de espermatozoides. Os touros parecem ter cromatina estável com baixos níveis de fragmentação do DNA. No entanto, a natureza da fragmentação e o seu impacto sobre a fertilidade ainda não estão claros e não há relatos que caracterizam a organização do DNA e os danos nessa espécie com mais detalhes. A seleção genética intensiva e o uso da inseminação artificial e da produção in vitro de embriões, além do processo de criopreservação, podem contribuir para o dano da cromatina, e sabe-se a importância da integridade do DNA espermático para o sucesso dessas tecnologias. Amostras de sêmen de três ejaculados de um touro Nelore com altos níveis de alterações morfológicas (55,8±5,1%) foram selecionadas para realização de exames complementares. Os danos de acrossoma (76,9±8,9%) e das membranas plasmáticas (75,7±9,3%), bem como quebras de fita de DNA de espermatozoides (13,8±9,5) e deficiência de protamina (3,7±0,6) foram significativamente maiores em comparação aos valores avaliados no sêmen de cinco touros Nelore com normospermia (24,3±3,3%; 24,5±6,1%; 0,6±0,5%; 0,4±0,6% para acrossoma, membrana plasmática, quebras de DNA e deficiência de protamina, respectivamente) (p<0,05). Motilidade e porcentagem de espermatozoides com baixo potencial mitocondrial não diferiram estatisticamente. Essas avaliações mostram que análises de sêmen de rotina (neste caso, morfologia) podem apontar para a extensão e a complexidade dos danos na célula espermática, o que indica que a deficiência de protamina e os danos no DNA podem ocorrer simultaneamente a defeitos morfológicos. Tal ocorrência enfatiza a importância das análises de sêmen clássicas e dos testes complementares.(AU)


Asunto(s)
Animales , Masculino , Bovinos , Semen , Espermatozoides/ultraestructura , Cromatina , Protaminas
19.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 58(5): 267-273, sept.-oct. 2014.
Artículo en Español | IBECS | ID: ibc-127029

RESUMEN

Objetivo. Tras el implante de algunos modelos de prótesis de cadera metal-metal se produce una elevación de los niveles de metales en suero y orina. Recientemente se ha demostrado que hay concordancia entre estas cifras y los niveles encontrados en el cabello. Nuestro objetivo ha sido estudiar la presencia de metales en cabello y conocer si ello se modifica con el paso del tiempo o con la extracción del implante. Material y método. En 45 pacientes con una artroplastia de superficie se ha realizado una determinación de los niveles de cromo, cobalto y molibdeno en cabello a los 3, 4, 5 y 6 años desde el implante. La edad media fue de 57,5 años, 2 eran mujeres. En 11 pacientes, en 5 de ellos por metalosis y quiste periarticular, fue necesaria una reintervención para extracción de la artroplastia e implante de un nuevo modelo con fricción metal-polietileno. Resultados. Las cifras medias de metales en cabello fueron cromo 163,27 ppm, cobalto 61,98 ppm y molibdeno 31,36 ppm, muy por encima de los niveles referidos en la población general. En los pacientes reintervenidos para extracción de la artroplastia se observó al año de la intervención una disminución del 43,8% en los niveles de cromo, del 51,1% en molibdeno y del 90,3% en cobalto. Conclusiones. En las artroplastias de cadera con fricción metal-metal se aprecia una alta concentración de metales en el cabello, que disminuye cuando dicho implante es extraído. La determinación de iones en cabello puede ser un buen marcador de la intoxicación por metales que sucede en estos modelos artroplásticos (AU)


Objective. There is an increase in the levels of metals in the serum and urine after the implantation of some models of metal-metal hip prosthesis. It has recently been demonstrated that there is an association between these levels and the levels found in hair. The aim of this study is to determine the presence of metals in hair, and to find out whether these change over time or with the removal of the implant. Material and method. The levels of chromium, cobalt and molybdenum were determined in the hair of 45 patients at 3, 4, 5, and 6 years after a hip surface replacement. The mean age was 57.5 years, and two were female. Further surgery was required to remove the replacement and implant a new model with metal-polyethylene friction in 11 patients, 5 of them due to metallosis and a periarticular cyst. Results. The mean levels of metals in hair were chromium 163.27 ppm, cobalt 61.98 ppm, and molybdenum 31.36 ppm, much higher than the levels found in the general population. A decrease in the levels of chromium (43.8%), molybdenum (51.1%), and cobalt (91.1%) was observed at one year in the patients who had further surgery to remove the prosthesis. Conclusions. High concentrations of metals in the hair are observed in hip replacements with metal-metal friction, which decrease when that implant is removed. The determination of metal ions in hair could be a good marker of the metal poisoning that occurs in these arthroplasty models (AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Iones Pesados/efectos adversos , Iones/efectos adversos , Cabello/patología , Enfermedades del Cabello/inducido químicamente , Enfermedades del Cabello/complicaciones , Artroplastia de Reemplazo de Cadera , Metales/efectos adversos , Prótesis e Implantes/efectos adversos , Prótesis e Implantes
20.
Rev Esp Cir Ortop Traumatol ; 58(5): 267-73, 2014.
Artículo en Español | MEDLINE | ID: mdl-24636447

RESUMEN

OBJECTIVE: There is an increase in the levels of metals in the serum and urine after the implantation of some models of metal-metal hip prosthesis. It has recently been demonstrated that there is an association between these levels and the levels found in hair. The aim of this study is to determine the presence of metals in hair, and to find out whether these change over time or with the removal of the implant. MATERIAL AND METHOD: The levels of chromium, cobalt and molybdenum were determined in the hair of 45 patients at 3, 4, 5, and 6 years after a hip surface replacement. The mean age was 57.5 years, and two were female. Further surgery was required to remove the replacement and implant a new model with metal-polyethylene friction in 11 patients, 5 of them due to metallosis and a periarticular cyst. RESULTS: The mean levels of metals in hair were chromium 163.27 ppm, cobalt 61.98 ppm, and molybdenum 31.36 ppm, much higher than the levels found in the general population. A decrease in the levels of chromium (43.8%), molybdenum (51.1%), and cobalt (91.1%) was observed at one year in the patients who had further surgery to remove the prosthesis. CONCLUSIONS: High concentrations of metals in the hair are observed in hip replacements with metal-metal friction, which decrease when that implant is removed. The determination of metal ions in hair could be a good marker of the metal poisoning that occurs in these arthroplasty models.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Cromo/análisis , Cobalto/análisis , Cabello/química , Prótesis Articulares de Metal sobre Metal , Molibdeno/análisis , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
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