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1.
Vascular ; : 17085381231153245, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689328

RESUMO

BACKGROUND: Focal peripheral arterial aneurysms, though rare, have a relatively high association with coexisting synchronous or metachronous aneurysms. While most are asymptomatic at presentation, there is concern for aneurysm thrombosis, embolization, or rupture, which can lead to acute limb ischemia or even limb loss. These complications require early intervention with either open or endovascular surgery, oftentimes staged due to complexity. METHOD: We describe a case of a 65-year-old male presenting with a symptomatic common femoral artery aneurysm with a simultaneous infrarenal abdominal aortic aneurysm, requiring a hybrid endovascular and open approach for operative repair due to the size and characteristics of his aneurysms. DISCUSSION: As the consensus for the management of synchronous/metachronous aneurysms is to stage the procedures, it is important to report scenarios where a single hybrid operation was technically feasible and resulted in good patient outcomes. CONCLUSION: This report supports the role of utilizing multiple hybrid operative techniques to best repair the respective aneurysm in a single operation, with favorable patient outcomes.

2.
Oral Dis ; 22(8): 735-739, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27133450

RESUMO

Salivary gland tumours represent a diverse range of tumours with many histological subtypes which occur in major and minor salivary glands. The management of these tumours is complex owing to their heterogeneity. Surgery together with radiotherapy and/or chemotherapy remains the treatment strategy for these tumours. The aim of this review is to examine the current management of these tumours.


Assuntos
Neoplasias das Glândulas Salivares/terapia , Terapia Combinada , Humanos , Pescoço/cirurgia , Neoplasias Parotídeas/cirurgia , Neoplasias Parotídeas/terapia , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias da Glândula Sublingual/cirurgia , Neoplasias da Glândula Sublingual/terapia , Neoplasias da Glândula Submandibular/cirurgia , Neoplasias da Glândula Submandibular/terapia
3.
Minerva Stomatol ; 64(3): 129-34, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25799446

RESUMO

AIM: The aim of the present study was to compare the apical microleakage of root canals obturated with AH Plus and MTA Fillapex® sealers. METHODS: A total of 76 anterior teeth were randomly divided into 4 groups (N.=15) and in each group 2 positive and 2 negative control teeth. All the teeth were cleaned, shaped and obturated using lateral compaction technique with gutta-percha and AH Plus® sealer in groups 1 and 2 and MTA Fillapex® sealer in groups 3 and 4. In groups 1 and 3 post spaces were prepared immediately and groups 2 and 4 were stored for 1 week at 100% relative humidity and then post spaces were prepared. The teeth were connected to a bacterial microleakage evaluation system. Each 72 hours, E. faecalis bacteria were inoculated into the coronal thirds of the root canals. The study period was 90 days and the samples were evaluated on a daily basis, Meier-Kaplan technique was used for estimation of the mean time of microleakage to occur. Log-rank test was used for comparison of microleakage. RESULTS: Contamination occurred in positive control groups on the first day of bacterial inoculation; however, the negative control groups did not exhibit any contamination up to the end of 90-day study period. the difference was not statistically significant between two materials (P>0.05). CONCLUSION: There were no significant differences between AH Plus® and MTA Fillapex® sealers with the two immediate and delayed postspace preparation techniques.


Assuntos
Compostos de Alumínio , Bactérias , Compostos de Cálcio , Infiltração Dentária , Resinas Epóxi , Óxidos , Materiais Restauradores do Canal Radicular , Silicatos , Combinação de Medicamentos , Técnicas In Vitro , Teste de Materiais , Técnica para Retentor Intrarradicular , Distribuição Aleatória , Fatores de Tempo
4.
Med Oral Patol Oral Cir Bucal ; 17(2): e331-6, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22143690

RESUMO

AIM: The aim of the present study was to electrochemically evaluate corrosion resistance of RaCe and Mtwo files after repeated sterilization and preparation procedures. STUDY DESIGN: A total of 450 rotary files were used. In the working groups, 72 files from each file type were distributed into 4 groups. RaCe and Mtwo files were used to prepare one root canal of the mesial root of extracted human mandibular first molars. The procedure was repeated to prepare 2 to 8 canals. The following irrigation solutions were used: group 1, RaCe files with 2.5% NaOCl; group 2, RaCe files with normal saline; group 3, Mtwo files with 2.5% NaOCl; and group 4, Mtwo files with normal saline in the manner described. In autoclave groups, 72 files from each file type were evenly distributed into 2 groups. Files were used for a cycle of sterilization without the use of files for root canal preparation. Nine new unused files from each file type were used as controls. Then the instruments were sent for corrosion assessment. Mann-Whitney U and Wilcoxon tests were used for independent and dependent groups, respectively. RESULTS: Statistical analysis indicated that there were significant differences in corrosion resistance of files associated with working and autoclave groups between RaCe and Mtwo file types (p<0.001). CONCLUSIONS: Corrosion resistance of #25, #30, and #35 Mtwo files is significantly higher than that in RaCe files with similar sizes.


Assuntos
Instrumentos Odontológicos , Níquel , Titânio , Corrosão , Técnicas Eletroquímicas , Desenho de Equipamento , Humanos , Teste de Materiais , Esterilização
5.
Sci Rep ; 12(1): 663, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027573

RESUMO

We investigate temperature, pressure, and localization dependence of thermoelectric properties, phonon and de Haas-van Alphen (dHvA) frequencies of the anti-ferromagnetic (AFM) CeIn[Formula: see text] using density functional theory (DFT) and local, hybrid, and band correlated functionals. It is found that the maximum values of thermopower, power factor, and electronic figure of merit of this compound occur at low (high) temperatures provided that the 4f-Ce electrons are (not) localized enough. The maximum values of the thermopower, power factor, electronic figure of merit (conductivity parameters), and their related doping levels (do not) considerably depend on the localization degree and pressure. The effects of pressure on these parameters substantially depend on the degree of localization. The phonon frequencies are calculated to be real which shows that the crystal is dynamically stable. From the phonon band structure, the thermal conductivity is predicted to be homogeneous. This prediction is found consistent with the thermal conductivity components calculated along three Cartesian directions. In analogous to the thermoelectric properties, it is found that the dHvA frequencies also depend on both pressure and localization degree. To ensure that the phase transition at Néel temperature cannot remarkably affect the results, we verify the density of states (DOS) of the compound at the paramagnetic phase constructing a non-collinear magnetic structure where the angles of the spins are determined so that the resultant magnetic moment vanishes. The non-collinear results reveal that the DOS and whence the thermoelectric properties of the compound are not changed considerably by the phase transition. To validate the accuracy of the results, the total and partial DOSs are recalculated using DFT plus dynamical mean-field theory (DFT+DMFT). The DFT+DMFT DOSs, in agreement with the hybrid DOSs, predict the Kondo effect in this compound.

6.
Opt Lett ; 36(20): 4047-9, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22002381

RESUMO

Design and fabrication of a 2×2 two-mode interference (TMI) coupler based on-chip polarization splitter is presented. By changing the angle between the access waveguides, one can tune the effective TMI length for the mode with less optical confinement (transverse magnetic, TM) to coincide with the target TMI length for a desired transmission of the mode with higher optical confinement (transverse electric, TE). The fabricated 0.94 µm long 2×2 TMI splits the input power into TM (bar) and TE (cross) outputs with splitting ratio over 15 dB over 50 nm bandwidth. Fabrication tolerance analysis shows that the device is tolerant to fabrication errors as large as 60 nm.

7.
Poult Sci ; 90(11): 2656-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22010255

RESUMO

Clostridium perfringens is recognized as an enteric pathogen in humans, domestic animals, and livestock. This organism is associated with necrotic enteritis, gangrenous dermatitis, clostridial dermatitis (turkeys), and gizzard erosions in poultry. This study was conducted to evaluate the effectiveness of a direct-fed microbial (DFM), Primalac (Star Labs, Clarksdale, MO), in preventing intestinal colonization of turkey poults with C. perfringens. One-day-old turkey poults (n = 128) were randomly divided into 4 treatments with 4 replicates (8 birds/pen). Treatments were as follows: 1) basal diet without DFM (C); 2) basal diet supplemented with Primalac (1.5 kg/ton; PM); 3) basal diet with poults gavaged with C. perfringens (CCP); and 4) basal diet supplemented with Primalac and poults gavaged with C. perfringens (PMCP). Feed and water were provided ad libitum throughout the trials, and birds were inoculated with C. perfringens (10(8)cfu/mL) on d 3 and 7. On d 21, 2 birds/pen were killed, spleen and bursa of Fabricius were collected and weighed, and cecal contents were used for C. perfringens enumeration. Feed consumption, BW, and feed conversion were calculated throughout the trial (weekly and cumulatively). Data were analyzed using GLM of SAS (SAS Institute, Cary, NC; P < 0.05). Among the inoculated groups, birds fed the DFM-supplemented diet had significantly lower cecal C. perfringens counts than the birds fed the diet without the DFM. The C. perfringens (log(10) cfu/g) in ceca were as follows: C, 5.88; CCP, 7.26; PM, 5.35; PMCP, 6.19 ± 0.36. No differences were observed for BW (814 ± 11 g), feed conversion (1.33 ± 0.03), organ weights, or relative organ weights. Further studies are needed to fully ascertain the potential of using DFM to reduce the numbers of C. perfringens in the gastrointestinal tract of turkey poults.


Assuntos
Infecções por Clostridium/veterinária , Clostridium perfringens , Probióticos/farmacologia , Perus , Aumento de Peso , Animais , Portador Sadio , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle , Enteropatias/microbiologia , Enteropatias/veterinária , Intestinos/microbiologia
8.
J Microsc ; 233(3): 423-31, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19250463

RESUMO

Grain boundary engineering has been proposed to increase the lifetime performance of sensitized austenitic stainless steel in aggressive environments. Increased microstructure resistance is typically associated with higher fractions of twin (Sigma3) grain boundaries, but there is uncertainty about the properties and role of other boundaries. To develop predictive models for stress corrosion crack nucleation, more information is required about how grain boundary crystallography and the orientations of the grain boundary plane and its surrounding grains affect crack development. Digital image correlation combined with electron backscatter diffraction has been used to characterize the microstructure and to observe, in situ, the nucleation and propagation of short stress corrosion cracks in thermo-mechanically processed type 304 stainless steel. The crack path and its growth rate have been determined and are found to be influenced by the microstructure.

9.
Poult Sci ; 88(3): 491-503, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19211517

RESUMO

The effects of dietary supplementation of the direct-fed microbial (DFM) Primalac in mash or crumbled feed on histological and ultrastructural changes of intestinal mucosa was determined in 2 populations of poults; 1 with and 1 without a Salmonella spp. challenge. Three hundred thirty-six 1-d-old female Large White turkey poults were randomly distributed into 8 treatment groups with 6 replicates of 7 poults in each pen. The poults were placed on 1 of 4 dietary treatments in a 2 x 2 x 2 factorial arrangement (mash or crumble feed, with or without DFM, not-challenged or challenged at 3 d of age). The DFM groups were fed a Primalac-supplemented diet from d 1 until the last day of the experiment (d 21). At 3 d of age, 50% of the poults were challenged with 1 mL of 10(10) cfu/ mL of Salmonella spp. (Salmonella enterica serovar Typhimurium, Salmonella Heidelberg, and Salmonella Kentucky) by oral gavage. The inoculated poults were housed in a separate room from nonchallenged controls. Feed and water were provided ad libitum for all birds. At d 21, 1 poult per pen (total of 6 poults per treatment) was randomly selected and killed humanely by cervical dislocation. After necropsy, the small intestine was removed, and tissue samples from duodenum, jejunum, and ileum were taken for light and electron microscopic evaluation. The DFM birds showed increased goblet cell (GC) numbers, total GC area, GC mean size, mucosal thickness, and a greater number of segmented filamentous bacteria compared with controls. Changes in intestinal morphology as observed in this study support the concept that poultry gut health and function, and ultimately bird performance, can be improved by dietary supplementation with DFM products such as Primalac as used in this study.


Assuntos
Intestino Delgado/efeitos dos fármacos , Probióticos/farmacologia , Perus , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Intestino Delgado/ultraestrutura , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle
10.
J Biomed Phys Eng ; 9(1): 37-50, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30881933

RESUMO

BACKGROUND: Estimating dosimetric parameters for small fields under non-reference conditions leads to significant errors if done based on conventional protocols used for large fields in reference conditions. Hence, further correction factors have been introduced to take into account the influence of spectral quality changes when various detectors are used in non-reference conditions at different depths and field sizes. OBJECTIVE: Determining correction factors (KNR and KNCSF) recommended recently for small field dosimetry formalism by American Association of Physicists in Medicine (AAPM) for different detectors at 6 and 18 MV photon beams. METHODS: EGSnrc Monte Carlo code was used to calculate the doses measured with different detectors located in a slab phantom and the recommended KNR and KNCSF correction factors for various circular small field sizes ranging from 5-30 mm diameters. KNR and KNCSF correction factors were determined for different active detectors (a pinpoint chamber, EDP-20 and EDP-10 diodes) in a homogeneous phantom irradiated to 6 and 18 MV photon beams of a Varian linac (2100C/D). RESULTS: KNR correction factor estimated for the highest small circular field size of 30 mm diameter for the pinpoint chamber, EDP-20 and EDP-10 diodes were 0.993, 1.020 and 1.054; and 0.992, 1.054 and 1.005 for the 6 and 18 MV beams, respectively. The KNCSF correction factor estimated for the lowest circular field size of 5 mm for the pinpoint chamber, EDP-20 and EDP-10 diodes were 0.994, 1.023, and 1.040; and 1.000, 1.014, and 1.022 for the 6 and 18 MV photon beams, respectively. CONCLUSION: Comparing the results obtained for the detectors used in this study reveals that the unshielded diodes (EDP-20 and EDP-10) can confidently be recommended for small field dosimetry as their correction factors (KNR and KNCSF) was close to 1.0 for all small field sizes investigated and are mainly independent from the electron beam spot size.

11.
Poult Sci ; 87(7): 1464-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18577631

RESUMO

A study was conducted to determine 1) the effect of a dietary direct-fed microbial (DFM) on turkey poult performance, 2) the effect of a DFM on a Salmonella challenge, and 3) the effect of feed processing on the efficacy of the dietary DFM. Day-of-hatch Large White female poults were placed in 2 rooms in 2 Petersime batteries per room. Twelve pens of 7 birds each were used in each battery (24 pens per room, 336 birds total). One of 4 dietary feed treatments was assigned to each pen (6 pens per room for each diet). One room housed non-Salmonella-challenged poults, and the other room housed poults challenged with a 1-mL oral gavage of Salmonella (10(10) cfu/mL). A single batch of starter ration was split into 4 parts and used to provide 4 dietary treatments: 1) mash feed with no DFM (M), 2) mash feed with DFM (Primalac; 0.9 kg/tonne of feed, MD), 3) pelleted (20-s steam conditioning at 80 degrees C) and crumbled feed with no DFM (C), and 4) pelleted and crumbled feed with DFM (CD). Feed and deionized, distilled water were provided ad libitum. Data were collected and analyzed separately for each room. Mortality was recorded for each pen on a daily basis and totaled by week and for the 3-wk period. Individual BW and feed consumption, by pen, were measured weekly. Weekly and cumulative BW gains and feed to gain ratios (F:G) were calculated. Liver, spleen, total and lower intestinal tract weights, intestinal length, and most-probable-number Salmonella populations were determined for one randomly selected bird per pen. Feeding processed feed resulted in improved BW and F:G. Feeding the DFM improved 3-wk cumulative F:G in birds not gavaged and reduced relative intestinal weight in birds gavaged. Salmonella populations were reduced 1 log by feeding DFM. Dietary DFM improved bird performance, reduced Salmonella populations, and was not affected by feed processing.


Assuntos
Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Salmonelose Animal/prevenção & controle , Perus/crescimento & desenvolvimento , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Doenças das Aves Domésticas/tratamento farmacológico
12.
Poult Sci ; 97(7): 2582-2590, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29584912

RESUMO

Avian semen cryopreservation is not as successful as that seen in mammals. This failure is mostly attributed to unique physiological characteristics of poultry semen that make it susceptible to cryo-damages. Utilization of sublethal oxidative stress for preconditioning of sperm, as an innovative approach, improves the cryo-survival of sperm in certain mammalian species. The purpose of this study was to investigate the effects of preconditioning of rooster semen with sublethal oxidative stress [very low concentrations of nitric oxide (NO)] before cryopreservation on the quality and fertility potential of thawed sperm. Semen samples were collected from 20 roosters, twice a wk, and different concentrations of NO [0 (NO-0), 0.01 (NO-0.01), 0.1 (NO-0.1), 1 (NO-1), 10 (NO-10), and 100 µM (NO-100)] were used to investigate the effects of controlled induction of sublethal stress before semen cryopreservation on the thawed sperm performance. A significantly higher (P < 0.05) percentage of total motility was observed in semen treated with NO-1 compared to NO-0, NO-0.01, NO-0.1, NO-10, and NO-100. NO-1 and NO-100 produced the highest and lowest percentages of progressive motility, which were significantly different from that of the other groups (P < 0.05). A significantly higher (P < 0.05) percentage of sperm mitochondria activity was observed in semen exposed to NO-0, NO-0.01, NO-0.1, and NO-1. Moreover, the lowest (P < 0.05) concentration of malondialdehyde (MDA) was measured in samples treated with NO-1 in comparison to the other groups. Abnormal morphology, acrosome integrity, and velocity parameters [velocity average path (VAP) and linearity (LIN)] of sperm were not significantly (P > 0.05) affected by different concentrations of NO. Sperm exposed to NO-1 produced the highest percentage of viable spermatozoa (Annexin-/PI-), which was significantly different from the other samples. Finally, rate of fertility after artificial insemination was significantly higher (P < 0.05) following treatment with NO-1 compared to NO-0 and NO-0.1. Application of 1 µM NO as a sublethal oxidative stress before cryopreservation of sperm efficiently increased numerous quality indices of thawed sperm as well as its fertility potential.


Assuntos
Galinhas/fisiologia , Criopreservação/veterinária , Fertilidade , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Animais , Criopreservação/métodos , Masculino , Óxido Nítrico/análise , Estresse Oxidativo , Preservação do Sêmen/métodos , Espermatozoides/fisiologia
13.
J Matern Fetal Neonatal Med ; 20(10): 709-14, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17763270

RESUMO

The bladder-flap hematoma (BFH) is an unusual complication of the cesarean section (CS) performed by Misgaw Ladach method or Stark CS (performed without peritoneal closure) and it is an usual event after the visceral peritoneal closure performed during the traditional method. A BFH is generally thought of as a blood collection located in a space placed between the bladder and lower uterine segment (LUS), called vescico-uterine space. If, during a Stark CS, pathological fluid collections arise in this space by uterine suture bleeding, these decant into the large peritoneal cavity causing a hemoperitoneum. This last complication can be easily and accurately detectable by ultrasonography, which can be utilised by non-invasive monitoring as a guide for the clinical follow-up. In the authors' experience, the CS by Stark method is associated with a lower febrile and infective morbidity and it is possible also to perform a successful conservative laparoscopy for the BFH management. Laparoscopical treatment of BFH offers to patients the potential clinical benefits of the minimally invasive endoscopical treatments, but it should be reserved for surgeons trained in extensive laparoscopic procedures.


Assuntos
Cesárea/efeitos adversos , Hematoma/cirurgia , Hemoperitônio/cirurgia , Laparoscopia/métodos , Adulto , Cesárea/métodos , Feminino , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Hemoperitônio/diagnóstico por imagem , Hemoperitônio/etiologia , Humanos , Hemorragia Pós-Operatória/complicações , Hemorragia Pós-Operatória/diagnóstico por imagem , Gravidez , Técnicas de Sutura , Ultrassonografia , Doenças da Bexiga Urinária/diagnóstico por imagem , Doenças da Bexiga Urinária/etiologia , Doenças da Bexiga Urinária/cirurgia
14.
Food Chem ; 196: 1040-7, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26593587

RESUMO

Pre-harvest foliar spraying of grapevines with putrescine (Put) and spermidine (Spd) (0, 1, 2mM) was evaluated for determining the fruit quality at harvest and improving postharvest characteristics of table grapes during cold storage. Fruit parameters in terms of firmness, fungal infection, weight loss, total phenol concentration, antioxidant activity, skin color, total anthocyanin concentration, total soluble solids (TSS) and titratable acidity (TA) were evaluated after 0, 25 and 55 days of storage at 1.5 ± 1 °C and 90 ± 5% R.H. Softening, fungal infection and weight loss increased during cold storage but the rate of changes significantly was delayed in Put- and Spd-treated fruits. Besides these, the application of Put and Spd maintained higher values of phenolics content, antioxidant activity and anthocyanins at the end of storage in compare to control. Furthermore, after 55 days of storage all treated fruits with Put and Spd showed lower changes in L(∗), TSS and TA and also higher value of chroma in berries.


Assuntos
Frutas/química , Poliaminas/química , Vitis/química , Antocianinas/análise , Antioxidantes , Fenóis/análise , Putrescina
15.
J Anim Sci ; 94(4): 1493-500, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27136008

RESUMO

Pulmonary hypertension syndrome (PHS), or ascites, is characterized by elevated pulmonary arterial pressure and pulmonary vascular resistance accompanied by right ventricular hypertrophy (RVH) and fluid accumulation in the abdominal cavity. Experimental models are required for triggering PHS to study the pathogenesis of this syndrome and to select resistant genetic lines. Caffeine increases vascular resistance and promotes systemic hypertension in mammals, but a similar effect of caffeine on the pulmonary circulation had not previously been demonstrated. Two experiments were conducted to evaluate the impact of caffeine alone (Exp. 1) or in combination with cold temperature (Exp. 2) on parameters associated with PHS in young broiler chicks. In Exp. 1, 288 chicks were distributed among 24 pens and brooded at standard environmental temperatures, and on d 3 through 42 caffeine was added to the water at doses of 0 (control), 6.25, 12.5, 25, 50, and 100 mg/(kg BW·d). In Exp. 2, 192 chicks were distributed among 16 pens and brooded at cool environmental temperatures, and on d 3 through 42 caffeine was added to the water at doses of 0 (control), 15, 30, and 45 mg/(kg BW·d). In Exp. 1 caffeine administered at or above 12.5 mg/(kg BW·d) induced severe PHS and resulted in acute mortality and RVH ( < 0.05). Hematocrit also slightly increased by caffeine supplementation ( = 0.07). In Exp. 2 caffeine-treated broilers exposed to cold temperatures remarkably exhibited PHS incidences and developed RVH with right ventricular to total ventricular weight ratios of 30% or greater. Moreover, hematocrit significantly increased because of caffeine supplementation in cool ambient temperature ( = 0.002). Our data demonstrate that caffeine induces high incidences of PHS in broilers, which is exacerbated by exposure to low temperatures.


Assuntos
Ascite/veterinária , Cafeína/toxicidade , Galinhas , Hipertensão Pulmonar/veterinária , Doenças das Aves Domésticas/induzido quimicamente , Animais , Ascite/induzido quimicamente , Temperatura Baixa , Suplementos Nutricionais , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/patologia , Pulmão/irrigação sanguínea , Masculino , Artéria Pulmonar , Temperatura , Resistência Vascular
16.
Nanoscale ; 8(14): 7523-33, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26902897

RESUMO

Here we present a very fast, selective mechanical approach for transferring graphene with low levels of copper contamination from seed wafers on which it was grown to target wafers for very large scale integration (VLSI) electronics. We found that graphene/copper or copper/silicon oxide delamination paths could be selected by slow and faster separation rates, respectively. Thus graphene can be transferred to a target wafer, either exposed or protected by the seed copper layer, which can later be removed by etching. Delamination paths were identified by SEM and Raman spectroscopy. The sheet resistance of the graphene produced by the two approaches was slightly higher than graphene transferred by a PMMA wet-transfer process, indicating reduced impurity doping, and the variation in the sheet resistance values was much lower. Copper contamination levels, quantitatively established by TOF-SIMS, were several orders of magnitude lower than the values for PMMA assisted transfer. In addition, we demonstrated that top-gated transistor devices from our mechanical, delamination transferred graphene exhibited superior transistor behavior to PMMA-assisted wet transfer graphene. The adhesion energy, strength and range of the interactions were quantitatively determined by nonlinear fracture analyses, and suggest that the roughness of the interface between graphene and copper plays an important role with implications for improvements in manufacturing processes.

17.
J Biomed Phys Eng ; 5(3): 121-32, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26396968

RESUMO

BACKGROUND: The rapid development of wireless telecommunication technologies over the past decades, has led to significant changes in the exposure of the general public to electromagnetic fields. Nowadays, people are continuously exposed to different sources of electromagnetic fields such as mobile phones, mobile base stations, cordless phones, Wi-Fi routers, and power lines. Therefore, the last decade witnessed a rapidly growing concern about the possible health effects of exposure to electromagnetic fields emitted by these sources. MATERIALS AND METHODS: In this study that was aimed at investigating the effects of exposure to radiofrequency (RF) radiation emitted by a GSM mobile phone on the pattern of contraction in frog's isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz), pulse height of contractions, the time interval between two subsequent contractions and the latency period were measured. RESULTS: Our findings showed that the pulse height of contractions muscle could be affected by the exposure to electromagnetic fields. Especially, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. CONCLUSION: These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions.

18.
J Biomed Phys Eng ; 5(3): 133-42, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26396969

RESUMO

INTRODUCTION: The rapid growth of wireless communication technologies has caused public concerns regarding the biological effects of electromagnetic radiations on human health. Some early reports indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians such as the alterations of the pattern of muscle extractions. This study is aimed at investigating the effects of exposure to radiofrequency (RF) radiation emitted from mobile phone jammers on the pulse height of contractions, the time interval between two subsequent contractions and the latency period of frog's isolated gastrocnemius muscle after stimulation with single square pulses of 1V (1 Hz). MATERIALS AND METHODS: Frogs were kept in plastic containers in a room. Animals in the jammer group were exposed to radiofrequency (RF) radiation emitted from a common Jammer at a distance of 1m from the jammer's antenna for 2 hours while the control frogs were only sham exposed. Then animals were sacrificed and isolated gastrocnemius muscles were exposed to on/off jammer radiation for 3 subsequent 10 minute intervals. Isolated gastrocnemius muscles were attached to the force transducer with a string. Using a PowerLab device (26-T), the pattern of muscular contractions was monitored after applying single square pulses of 1V (1 Hz) as stimuli. RESULTS: The findings of this study showed that the pulse height of muscle contractions could not be affected by the exposure to electromagnetic fields. However, the latency period was effectively altered in RF-exposed samples. However, none of the experiments could show an alteration in the time interval between two subsequent contractions after exposure to electromagnetic fields. CONCLUSION: These findings support early reports which indicated a wide variety of non-thermal effects of electromagnetic radiation on amphibians including the effects on the pattern of muscle extractions.

19.
J Biomed Phys Eng ; 5(2): 59-66, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26157731

RESUMO

INTRODUCTION: Oral intake of vitamins which present antioxidant characteristics can protect living organisms against oxidative damage caused by exposure to ionizing radiation. It was previously reported that administration of high levels of vitamin C can lead to increased DNA damage through production of hydroxyl radicals from hydrogen peroxide by the Fenton reaction. However, our early experiments did not confirm this hypothesis. The main goal of this study was to determine if high doses of Vit C can show life-saving radioprotective effects. MATERIALS AND METHODS: Phase I: Seventy two male Balb/c mice weighing 20-25g were randomly divided into six groups of 12 animals each. Group I; Vit E for five days, Groups II and III; Vit C and Vit A. Group 4; all three vitamins. Group V; an over-the-counter multivitamin. Group VI; none of the above. Phase II: 120 male BALB/c mice weighing 20-25g were randomly divided into 12 groups of 10 each. Group I; Vit A for five days. Groups II-IV; Vit C 200 mg/kg, 400 mg/kg, 800 mg/kg, respectively. Group V-VII; Vit E at daily doses of 200 iu/kg, 400 iu/kg, 800 iu/kg, respectively. Group VIII and IX; all three vitamins at low and high doses, respectively. Group X; an over-the-counter multivitamin. Group XI; controls group and Group XII; received pure olive oil. All animals (Phases I and II) were exposed to a lethal dose of gamma rays and the survival rates of the animals were monitored and recorded continuously for 16 days after exposure. RESULTS: Phase I: 14 days after irradiation the survival rate for control group was 33.33%, while the survival rates for the 1st to 5th groups were 45.45%, 81.81%, 50%, 57.14%, and 9.09% , respectively. Phase II: The survival rates in the control group and the group that only received pure olive oil, were 50% and 60%, respectively. Survival rate in the animals received Vit C at daily doses of 200 mg/kg, 400 mg/kg, 800 mg/kg, were 90%, 90% and 90%, respectively. Log rank (Mantel-Cox) test showed statistically significant differences between the survival rates in control irradiated mice (no vitamins) and mice received Vit C at daily doses of 200 mg/kg (P=0.042), 400 mg/kg (P=0.042) and 800 mg/kg (P=0.042). CONCLUSION: Altogether, findings of this study showed that even high doses of Vit C can show life-saving radioprotective effects. The significant radioprotective effect of Vit C at doses used in this study, opens new horizons in developing non-toxic, cost effective, easily available radioprotectors in life-threatening situations such as exposure to lethal doses of ionizing radiation.  The radioprotective effect of Vit A and Vit E seem to be less efficient compared to that of Vit C.

20.
Am J Kidney Dis ; 34(1): 85-91, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10401020

RESUMO

Subepithelial deposits are a common feature of idiopathic membranous glomerulonephritis (MGN) and lupus membranous glomerulopathy (LMGN). We investigated the spatial arrangement of immunoglobulin G (IgG) and C3c fraction of complement (C3c) in the immune deposits of MGN and LMGN with confocal laser scanning microscopy to correlate specific patterns of IgG-C3 interactions with different diseases. Ten patients with MGN and 8 patients with LMGN (World Health Organization class VB) were selected. A determination of the spatial arrangement of the two fluorochromes and the glomerular area occupied by each fluorochrome was performed for each case. Our results showed MGN specimens have an orderly distribution of IgG and C3c, with each deposit showing an outer ring of sole IgG. IgG was always more abundant than C3c (1,619 +/- 271 v 790 +/- 105 micrometer(2), P = 0.002). In LMGN, IgG and C3c were haphazardly arranged, with deposits made of C3c only and an outer ring of IgG only rarely present. Also, the relative amounts of the two antigens were variable, and two groups could be identified (group 1: IgG, 5,515 +/- 1,179 micrometer(2) v C3c, 4,810 +/- 1,174 micrometer(2); P = 0.02; group 2: IgG, 3,358 +/- 658 micrometer(2) v C3c, 4,047 +/- 740 micrometer(2); P = 0.03). Our data show that diffuse IgG capping of the subepithelial immune deposits is diagnostic of MGN. The absence of an orderly three-dimensional arrangement in LMGN deposits (ie, outer ring of IgG) is likely to render active complement components more readily available to inflammatory activities.


Assuntos
Complexo Antígeno-Anticorpo/análise , Glomerulonefrite Membranosa/patologia , Glomérulos Renais/imunologia , Nefrite Lúpica/patologia , Adulto , Idoso , Complemento C3c/análise , Feminino , Humanos , Imunoglobulina G/análise , Glomérulos Renais/patologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade
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