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1.
Traffic Inj Prev ; 23(6): 372-376, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35704680

RESUMO

OBJECTIVE: The anthropomorphic test device (ATD) used in NCAP frontal impact, the Thor 50th, has undergone substantial changes for safety restraint systems testing of upcoming autonomous vehicles (AVs), resulting in the Thor-AV 50 M. Likewise, a deep analysis of the ATD for lateral impacts, the WorldSID 50th, is needed to determine the requirements it has to fulfill to accurately replicate the human body response under lateral impact. This study sets out general considerations regarding the WorldSID 50th ATD design in order to assess its suitability for AV testing scenarios. METHODS: The WorldSID 50th ATD was placed in a driver seat at a conventional upright driving posture. Relevant body landmarks and angles as well as profile streams of the mockup and the ATD were recorded. The seatback was then reclined stepwise. The ATD was repositioned and the recording procedure repeated at every posture until the seatback was fully reclined. Examination of the ATD assemblies and hinge mechanisms was performed, searching for limitations that could result on inadequate positioning or performance under impact. An eventual SAEJ3016 Level 3 cross-legged posture (SAE J3016, 2021) was considered for examination as well. RESULTS: Most relevant anthropometric constraints were noticed at the abdomen and the shoulder and neck assemblies: At the abdomen, a gap between the pelvis and the lower torso appeared at seatback recline angles larger than 30°, likely promoting belt intrusion in case of a test event, and the lumbar spine rubber deformed progressively in a manner that might cause tearing damage. The number and arrangement of the shoulder clevis detents, on the other hand, did not allow the arm to be placed at intermediate positions. Finally, the current neck bracket design allowed head orientation only along the sagittal plane. The head could neither be level at seatback angles larger than 43° nor be placed resting on the head restraint for seatback angle values larger than 59°. CONCLUSIONS: The WorldSID ATD stands as an accurate 50th percentile human being surrogate in upright and low/mid reclined postures. Some limitations that might constrain its use in AV scenarios, though, appeared at mid/high reclined positions. Hence, design updating of the lumbar, neck and shoulder clevis assemblies, and the implementation of instrumented lower abdomen and lower arms assemblies should be taken into consideration.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Fenômenos Biomecânicos , Desenho de Equipamento , Humanos , Manequins , Postura/fisiologia
2.
Traffic Inj Prev ; 23(3): 135-139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35191806

RESUMO

OBJECTIVE: Autonomous driving cars must be developed to ensure that children will have the highest level of protection in case of collision. Changes to the vehicle cabin design (different seat orientations, fully reclining seats, etc.) may significantly impact child occupant safety. Understanding child occupant responses under these new conditions is necessary to decrease risk and enhance child safety. In this study, child occupant response in different seating orientations exposed to frontal impacts with a focus on the head injuries and kinematics was analyzed. METHODS: Finite elements simulations were performed using the PIPER 6-year-old human body model (HBM). All simulations were carried out in a generic full vehicle environment. The child model was positioned in an adequate generic car restraint system (CRS) in the left rear vehicle seat in 4 seating orientations: 0° (forward-facing position), 30°, 60°, and 90° (living room position). Two scenarios were evaluated for all seating orientations according to the left front seat backrest position: reclined position nominal upright and rest position (55°). All seat configurations were subjected to the mobile progressive deformable barrier frontal impact (European New Car Assessment Programme [Euro NCAP] frontal impact testing protocol). A total of 8 scenarios were simulated in LS-DYNA. RESULTS: Based on the Euro NCAP injury risk rate, 90° seating orientation (living room position) was the safest among all selected scenarios independent of the left front seat backrest position. The worst case was found in 60° seat rotation. The highest values for Head Injury Criterion (HIC) and head acceleration (Acc 3 ms) were noted for this case. Higher Brain Injury Criterion (BrIC) values were observed at higher seat rotation angles. Hence, a 90° seating orientation showed the highest BrIC value. Attending to the skull stress, greater head injuries were caused principally by contact with the vehicle interior (seat headrest). Maximum stress values were reached at 30° and 60° seating orientations with the front seat in rest position. In 90° seating orientation, high stress values were also identified. CONCLUSIONS: These results show that attending to these new seating orientations, current child safety standards are not sufficient to ensure children the highest level of protection. Other additional criteria such as BrIC or skull stress that offer a way to capture brain injuries should be used.


Assuntos
Condução de Veículo , Corpo Humano , Acidentes de Trânsito , Automóveis , Fenômenos Biomecânicos , Criança , Humanos
3.
Cell Stress Chaperones ; 23(4): 609-615, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29288355

RESUMO

A dedicated UNC45, Cro1, She4 (UCS) domain-containing protein assists in the Hsp90-mediated folding of the myosin head. Only weak sequence conservation exists between the single UCS protein of simple eukaryotes (She4 in budding yeast) and the two UCS proteins of higher organisms (the general cell and striated muscle UNC45s; UNC45-GC and UNC45-SM, respectively). In vertebrates, UNC45-GC facilitates cytoskeletal functions, whereas the 55% identical UNC45-SM assists assembly of the contractile apparatus of cardiac and skeletal muscles. A Saccharomyces cerevisiae she4Δ mutant, totally lacking any UCS protein, was engineered to express as its sole Hsp90 either the Hsp90α or the Hsp90ß isoforms of human cytosolic Hsp90. A transient induction of the human UNC45-GC, but not UNC45-SM, could rescue the defective endocytosis in these she4Δ cells at 39 °C, irrespective of whether they possessed Hsp90α or Hsp90ß. UNC45-GC-mediated rescue of the localisation of a Myo5-green fluorescent protein (GFP) fusion to cortical patches at 39 °C was more efficient in the yeast containing Hsp90α, though this may relate to more efficient functioning of Hsp90α as compared to Hsp90ß in these strains. Furthermore, inducible expression of UNC45-GC, but not UNC45-SM, could partially rescue survival at a more extreme temperature (45 °C) that normally causes she4Δ mutant yeast cells to lyse. The results indicate that UCS protein function has been most conserved-yeast to man-in the UNC45-GC, not UNC45-SM. This may reflect UNC45-GC being the vertebrate UCS protein that assists formation of the actomyosin complexes needed for cytokinesis, cell morphological change, and organelle trafficking-events also facilitated by the myosins in yeast.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Chaperonas Moleculares/metabolismo , Mutação/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas do Citoesqueleto/genética , Citosol/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Temperatura Alta , Humanos , Viabilidade Microbiana , Chaperonas Moleculares/genética , Miosinas/metabolismo , Fenótipo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética
4.
Cell Stress Chaperones ; 22(1): 135-141, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27888470

RESUMO

Folding of the myosin head often requires the joint actions of Hsp90 and a dedicated UNC45, Cro1, She4 (UCS) domain-containing cochaperone protein. Relatively weak sequence conservation exists between the single UCS protein of simple eukaryotes (She4 in budding yeast) and the two UCS proteins of higher organisms (the general cell and smooth muscle UNC45s; UNC45-GC and UNC45-SM respectively). In vertebrates, UNC45-GC facilitates cytoskeletal function whereas the 55% identical UNC45-SM assists in the assembly of the contractile apparatus of cardiac and skeletal muscles. UNC45-SM, unlike UNC45-GC, shares with yeast She4 an IDSL sequence motif known to be a site of in vivo serine phosphorylation in yeast. Investigating this further, we found that both a non-phosphorylatable (S18A) and a phosphomimetic (S18E) mutant form of She4 could rescue the type 1 myosin localisation and endocytosis defects of the yeast she4Δ mutant at 39 °C. Nevertheless, at higher temperature (45 °C), only She4 (S18A), not She4(S18E), could substantially rescue the cell lysis defect of she4Δ mutant cells. In the yeast two-hybrid system, the non-phosphorylatable S18A and S251A mutant forms of She4 and UNC45-SM still displayed the stress-enhanced in vivo interaction with Hsp90 seen with the wild-type She4 and UNC45-SM. Such high-temperature enforcement to interaction was though lost with the phosphomimetic mutant forms (She4(S18E) and UNC45-SM (S251E)), an indication that phosphorylation might suppress these increases in She4/Hsp90 and UNC45-SM/Hsp90 interaction with stress.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Motivos de Aminoácidos , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Endocitose , Proteínas de Choque Térmico HSP90/metabolismo , Microscopia de Fluorescência , Mutagênese Sítio-Dirigida , Miosina Tipo I/metabolismo , Fenótipo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Temperatura , Técnicas do Sistema de Duplo-Híbrido
5.
Rev. calid. asist ; 22(2): 94-97, mar. 2007. ilus
Artigo em Es | IBECS | ID: ibc-053036

RESUMO

Objetivo: Comparar el control glucémico de pacientes diabéticos que pertenecen a un grupo de apoyo y de quienes no forman parte de él. Material y método: Estudio de casos y controles, con un total de 73 pacientes con diabetes mellitus tipo 2, pertenecientes al grupo de apoyo (n = 30) y al grupo control (n = 43). Se obtuvieron del expediente clínico los datos de glucemias, colesterol, triglicéridos, somatometría y número de veces en que se realizó la prueba durante el período de estudio. Se estratificaron los valores de acuerdo con los parámetros de normalidad y se estimaron las odds ratio [OR]. Resultados: Las glucemias en el grupo de apoyo fueron menores que en el grupo control (p 0,05). Al estimar el riesgo de presentar un valor de glucemia > 120 mg/dl, se encontró que los pacientes que pertenecen al grupo control tienen OR = 2,1 (0,7-6,2) respecto a los pacientes que pertenecen al grupo de apoyo. De igual manera, se obtuvo OR = 4,3 (1,4-12,8) de presentar un valor por arriba de lo normal de triglicéridos séricos para el grupo control con relación al grupo de apoyo. Conclusiones: Pertenecer a un grupo de apoyo no refleja un control y aunque las glucemias fueron menores en los controles, éstas no se ubicaban por debajo del límite recomendado. Asimismo, es importante destacar que en estas unidades médicas no se cuenta con hemoglobina glucosilada y, por lo tanto, la medida utilizada para evaluación y control en el paciente diabético son las glucemias


Objective: To compare glycemic control in diabetic patients belonging to support groups with that in diabetic patients not belonging to support groups. Material and method: A case-control study with 73 patients with diabetes mellitus type 2 belonging to a support group (n = 30) or a control group (n = 43) was performed. Data on height, weight, and levels of glycemia, cholesterol, and triglycerides, as well as the number of times laboratory tests were carried out during the study period, were obtained from the medical records. The values were stratified according to the parameters of normality and odds ratios between the support group and the control group were estimated. Results: Glucose levels were lower in patients attending support groups than in controls (p 0.05). Controls had an OR of 2.1 (0.7-6.2) for glucose levels of up to 120 mg/dl in relation to patients attending support groups. Similarly, controls had an OR of 4.3 (1.4-12.8) of presenting serum triglyceride levels above the normal range in relation to patients in the support groups. Conclusions: Belonging to a support group is not an indication of metabolic control. Although glucose levels were lower in patients belonging to support groups than in controls, these levels were not below the recommended range. Importantly, the family medicine units did not include glycosylated hemoglobin values and therefore the measure used for evaluation and control in diabetic patients was fasting glucose levels


Assuntos
Humanos , Grupos de Autoajuda , Diabetes Mellitus Tipo 2/sangue , Estudos de Casos e Controles , Triglicerídeos/sangue , Colesterol/sangue , Razão de Chances , Índice Glicêmico
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