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1.
Health Phys ; 119(2): 236-246, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32576739

RESUMO

This COMAR Technical Information Statement (TIS) addresses health and safety issues concerning exposure of the general public to radiofrequency (RF) fields from 5G wireless communications networks, the expansion of which started on a large scale in 2018 to 2019. 5G technology can transmit much greater amounts of data at much higher speeds for a vastly expanded array of applications compared with preceding 2-4G systems; this is due, in part, to using the greater bandwidth available at much higher frequencies than those used by most existing networks. Although the 5G engineering standard may be deployed for operating networks currently using frequencies extending from 100s to 1,000s of MHz, it can also operate in the 10s of GHz where the wavelengths are 10 mm or less, the so-called millimeter wave (MMW) band. Until now, such fields were found in a limited number of applications (e.g., airport scanners, automotive collision avoidance systems, perimeter surveillance radar), but the rapid expansion of 5G will produce a more ubiquitous presence of MMW in the environment. While some 5G signals will originate from small antennas placed on existing base stations, most will be deployed with some key differences relative to typical transmissions from 2-4G base stations. Because MMW do not penetrate foliage and building materials as well as signals at lower frequencies, the networks will require "densification," the installation of many lower power transmitters (often called "small cells" located mainly on buildings and utility poles) to provide for effective indoor coverage. Also, "beamforming" antennas on some 5G systems will transmit one or more signals directed to individual users as they move about, thus limiting exposures to non-users. In this paper, COMAR notes the following perspectives to address concerns expressed about possible health effects of RF field exposure from 5G technology. First, unlike lower frequency fields, MMW do not penetrate beyond the outer skin layers and thus do not expose inner tissues to MMW. Second, current research indicates that overall levels of exposure to RF are unlikely to be significantly altered by 5G, and exposure will continue to originate mostly from the "uplink" signals from one's own device (as they do now). Third, exposure levels in publicly accessible spaces will remain well below exposure limits established by international guideline and standard setting organizations, including ICNIRP and IEEE. Finally, so long as exposures remain below established guidelines, the research results to date do not support a determination that adverse health effects are associated with RF exposures, including those from 5G systems. While it is acknowledged that the scientific literature on MMW biological effect research is more limited than that for lower frequencies, we also note that it is of mixed quality and stress that future research should use appropriate precautions to enhance validity. The authorship of this paper includes a physician/biologist, epidemiologist, engineers, and physical scientists working voluntarily and collaboratively on a consensus basis.


Assuntos
Radiação Eletromagnética , Exposição Ambiental , Comunicação , Campos Eletromagnéticos , Humanos , Micro-Ondas/efeitos adversos , Saúde Pública , Exposição à Radiação , Ondas de Rádio , Pele , Sociedades Científicas , Tecnologia , Tecnologia sem Fio
2.
Aesthetic Plast Surg ; 41(4): 845-855, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28451799

RESUMO

BACKGROUND: Frontal fullness in Asians is often considered to indicate one's public popularity and leadership skills. Numerous materials and techniques have been applied clinically to recontour or volumize the frontal area, with variable results. The micro-autologous fat transplantation (MAFT) technique proposed by Lin et al. (2nd academic congress of Taiwan Cosmetic Association Taipei, Taiwan) in 2007 has demonstrated its feasibility in facial rejuvenation. In the present study, we used an innovative instrument to apply the MAFT technique to frontal augmentation with fat grafting and reported the results. METHODS: MAFT was performed on 178 patients (167 female, 11 male) during a 5-year period starting in January 2010. Fat was harvested by liposuction, processed and refined by centrifugation at 1200×g for 3 min. The purified fat was micro-transplanted for frontal contouring with the assistance of an instrument, the MAFT-GUN. The patients were followed up regularly, and photographs were taken for comparison. RESULTS: On average, the MAFT procedure took 52 min to complete. The average amount of delivered fat was 10.2 mL. The follow-up period was 34 months on average. No complications, including neurovascular injury, skin necrosis, abscess, nodulation, calcification or irregularity, were noted. A patient-rated satisfaction 5-point Likert scale demonstrated that 83.1% of all patients had favorable results (48.3% were satisfied, and 34.8% were very satisfied). CONCLUSION: The concept and technique of MAFT has changed fat grafting from an operation with unpredictable clinical results to an easy, reliable and consistent procedure. Furthermore, the use of a precisely controlled instrument enabled surgeons to perform highly accurate micro-fat grafting. In comparison with other strategies for volume restoration, the MAFT procedure demonstrated high patient satisfaction with the long-term results. Therefore, the use of MAFT as an alternative approach to forehead contouring and volumizing was addressed. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Tecido Adiposo/transplante , Rejuvenescimento , Envelhecimento da Pele/fisiologia , Cirurgia Plástica/métodos , Adulto , Idoso , Envelhecimento , Estética , Feminino , Seguimentos , Testa/cirurgia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ritidoplastia , Medição de Risco , Estudos de Amostragem , Taiwan , Transplante Autólogo
3.
Electromagn Biol Med ; 34(3): 175-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26444189

RESUMO

Although there is scientific consensus that radiofrequency (RF) exposure at high intensity can cause thermal effects, including well-established adverse health effects, there is still considerable controversy on whether low-intensity RF exposure can cause biological effects, especially adverse health effects. The objective of this paper is to describe several reported "non-thermal" effects that were later shown to be due to a weak thermal effect or an experimental artifact by properly conducted and thorough follow-on scientific research. First, the multiple factors that can cause different RF energy absorption in biological tissues are reviewed and second, several examples of experimental artifacts in published papers are described to demonstrate the importance of paying attention to dosimetry and temperature control. For example, isolated nerve response studies show that when temperature of the RF-exposed tissues is controlled, effects disappeared. During RF exposure, conductive electrodes routinely used in physiological studies have been shown to cause field intensification at the tips or contacts of the electrodes with biological tissue; thus, the RF exposure at the site of measurement could be much higher than the incident field. In some in vitro studies, a lack of temperature uniformity in RF-exposed cell cultures and rate of heating explain changes originally reported to be due to low-level RF exposure. In other studies, detailed dosimetry studies have identified artifacts that explain the reasons why so-called "non-thermal" effects were mistakenly reported. Researchers should look for explanations for their own findings, and not expect others to figure out what was the reason for their observed effects.


Assuntos
Exposição à Radiação/efeitos adversos , Ondas de Rádio/efeitos adversos , Radiobiologia/métodos , Animais , Comportamento Animal/efeitos da radiação , Condutividade Elétrica , Eletrodos , Humanos , Sistema Nervoso/efeitos da radiação , Ratos , Temperatura
5.
Oncogene ; 29(41): 5619-29, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20676141

RESUMO

Histone deacetylase inhibitors (HDACi) are potent anti-cancer agents for variety of cancer types. Suberoylanilide hydroxamic acid (SAHA) has been approved as a drug to treat cutaneous T cell lymphoma, and the combination of HDACi and other agents have been actively tested in many clinical trials. Adenovirus 5 early region 1A (E1A) has been shown to exhibit high tumor suppressor activity, and gene therapy using E1A has been tested in clinical trials. Here, we showed that proapoptotic activity of HDACi was robustly enhanced by E1A in multiple cancer cells, but not in normal cells. Moreover, we showed that combination of E1A gene therapy and SAHA showed high therapeutic efficacy with low toxicity in vivo ovarian and breast xenograft models. SAHA downregulated Bcl-XL and upregulated proapoptotic BH3-only protein Bim, whose expression was further enhanced by E1A in cancer cells. These alterations of Bcl-2 family proteins were critical for apoptosis induced by the combination in cancer cells. SAHA enhanced acetylation of histone H3 in Bim promoter region, while E1A upregulated Egr-1, which was directly involved in Bim transactivation. Together, our results provide not only a novel insight into the mechanisms underlying anti-tumor activity of E1A, but also a rationale for the combined HDACi and E1A gene therapy in future clinical trials.


Assuntos
Proteínas E1 de Adenovirus/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Acetilação/efeitos dos fármacos , Proteínas E1 de Adenovirus/genética , Animais , Proteínas Reguladoras de Apoptose/genética , Proteína 11 Semelhante a Bcl-2 , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Imunoprecipitação da Cromatina , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Terapia Genética , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Proteínas de Membrana/genética , Camundongos , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Proteínas Proto-Oncogênicas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/efeitos dos fármacos , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Oncogene ; 26(29): 4272-83, 2007 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-17237822

RESUMO

A significant challenge in the post-genomic era is how to prioritize differentially expressed and uncharacterized novel genes found in hepatocellular carcinoma (HCC) microarray profiling. One such category is cell cycle regulated genes that have only evolved in higher organisms but not in lower eukaryotic cells. Characterization of these genes may reveal some novel human cancer-specific abnormalities. A novel transcript, FLJ10540 was identified. FLJ10540 is overexpressed in HCC as examined by quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. The patients with higher FLJ10540 expression had a poor survival than those with lower FLJ10540 expression. Functional characterization indicates that FLJ10540 displays a number of characteristics associated with an oncogene, including anchorage-independent growth, enhanced cell growth at low serum levels and induction of tumorigenesis in nude mice. FLJ10540-elicited cell transformation is mediated by activation of the phosphatidylinositol 3'-kinase (PI3K)/AKT pathway. Moreover, FLJ10540 forms a complex with PI3K and can activate PI3K activity, which provides a mechanistic basis for FLJ10540-mediated oncogenesis. Together, using a combination of bioinformatics searches and empirical data, we have identified a novel oncogene, FLJ10540, which is conserved only in higher organisms. The finding raises the possibility that FLJ10540 is a potential new therapeutic target for HCC treatment. These findings may contribute to the development of new therapeutic strategies that are able to block the PI3K/AKT pathway in cancer cells.


Assuntos
Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/fisiologia , Transformação Celular Neoplásica/patologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Proteínas Nucleares/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Humanos , Neoplasias Hepáticas/genética , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Células Tumorais Cultivadas
8.
Bioelectromagnetics ; 28(1): 3-15, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17016850

RESUMO

For 35 years, I have been involved in various bioelectromagnetics research projects including acute and long-term radiofrequency (RF) bioeffects studies, dosimetry, exposure systems, MRI safety, cancer studies involving hyperthermia and electrochemical treatment, development of RF exposure and measurement standards, and product compliance. My first study demonstrated that effects on isolated nerve and muscle preparations were due to thermal effects of RF exposure. The recording of cochlear microphonics in animals shows the mechanical nature of the microwave auditory effect. In 1992, we published the results of a large-scale lifetime study in which 100 rats were sham-exposed and 100 rats were exposed for 21 h/day for 25 months to a pulsed RF signal. In dosimetry studies, human models were employed as well as many animal species including mice, rats, rabbits, monkeys, and birds of many sizes. Cancer hyperthermia studies demonstrated that knowledge of temperature distribution was crucial for successful treatment. Research on electrochemical treatment of tumors with direct current involved cellular, animal, and clinical studies. Over the past few decades, there has been rather extensive investigation of the public health impact of RF exposure. In my opinion, future research in bioelectromagnetics should place greater emphasis on medical applications.


Assuntos
Pesquisa Biomédica/história , Magnetismo/história , Proteção Radiológica/história , Radiobiologia/história , História do Século XX , História do Século XXI , Estados Unidos
9.
Acta Radiol ; 47(7): 752-4, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16950717

RESUMO

Clinically symptomatic renal capsular leiomyomas are rare. Previous research has shown that these tumors are usually well-defined cystic lesions, solid lesions, or a mixture of the two. We report an unusual case of renal capsular leiomyoma which was well defined by ultrasonography, but lacked a well-defined edge in CT. The reason for the absence of a well-defined tumor edge is probably due to degeneration in certain parts of the tumor resulting in a different degree of enhancement. Thus, the possibility of renal capsular leiomyoma should be included in the differential diagnosis whenever a renal mass is found, especially when either CT or ultrasonography shows that the tumor has a smooth, well-defined contour.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Adulto , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Renais/cirurgia , Leiomioma/cirurgia , Nefrectomia , Tomografia Computadorizada por Raios X , Ultrassonografia
10.
Cancer Gene Ther ; 13(8): 746-52, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16410824

RESUMO

Antitumor vaccination therapies using attenuated Salmonella typhimurium carrying plasmid DNA encoding tumor-associated antigens are currently under preclinical development. In the present study, we first established a useful method to facilitate in vivo monitoring of attenuated S. typhimurium uptake using a bioluminescent lux gene operon plasmid. Following transformation with the lux gene operon construct, mice were fed with various amounts of attenuated S. typhimurium-lux to monitor in vivo clearance over a period of 24 h. We found that the ingested attenuated S. typhimurium-lux cells were almost cleared out 9 h postfeeding, as judged by a significant decrease in bioluminescence. We further examined the therapeutic efficacy of vaccination using attenuated S. typhimurium carrying the mouse alpha-fetoprotein (AFP) gene against a cancer line CT26-murine alpha-feto protein (mAFP) that stably expresses AFP and mouse hepatocellular carcinoma (HCC) Hepa1-6. Attenuated S. typhimurium oral DNA vaccine was found to promote protective immunity against both CT26-mAFP and Hepa1-6 tumor cells growth. The oral DNA vaccine significantly increased the life span of tumor-challenged mice in both tumor models. Together, these results suggest that vaccination with the attenuated S. typhimurium oral DNA vaccine that carries the AFP gene could be a promising strategy to prevent HCC development.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Salmonella typhimurium/imunologia , Vacinas de DNA/imunologia , alfa-Fetoproteínas/genética , Administração Oral , Animais , Antígenos de Neoplasias/imunologia , Carcinoma Hepatocelular/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Neoplasias do Colo/prevenção & controle , Citotoxicidade Imunológica , Genes Bacterianos , Humanos , Tolerância Imunológica , Neoplasias Hepáticas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Óperon , Plasmídeos , Salmonella typhimurium/genética , Linfócitos T/imunologia , Vacinas Atenuadas , Vacinas de DNA/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto , alfa-Fetoproteínas/imunologia
11.
Eye (Lond) ; 19(7): 784-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15359238

RESUMO

PURPOSE: The purpose of the present study was to investigate the incidence and severity of iridial pigmentation under latanoprost topical use on brown eyes in Taiwan. METHODS: Retrospective review study was conducted from April 1999 to October 2001 in the Department of Ophthalmology, Taipei Veterans General Hospital, Taiwan, for glaucoma clinic monthly follow-up patients; 140 open-angle glaucoma patients on 0.005% latanoprost were enrolled. Analyses of iridial pigmentation incidence, grading, patient age distribution, side effect, and time course were performed. Boys-Smith pigment gradation lens was used as standard for semiquantitative iris pigmentation grading. RESULT: Before 0.005% latanoprost use, 90% of the patients enrolled were noted with iridial pigmentation grade I, and 10% were with grade I-II, but not reaching grade II scale standard. A total of 60 patients on 0.005% latanoprost developed increased pigmentation of the iris during the follow-up period. An increase of iris pigmentation was noted after an average of 7.27 months use of latanoprost (range 1-19 months, SD 2.65 months). For iridial pigmentation grading, 57.1, 30.7, 10.0, and 2.1% of our patients were noted to have grade I, II, III, and IV respectively. Most patients with latanoprost-induced iris hyperpigmentation were with grade II iridial pigmentation. There were 15 patients (10.7%) (10 female and five male) with hypertrichosis in the study group who were not compatible with the iridial pigmentation status. Among these patients, female patients had higher incidence of hypertrichosis than males, but this did not bother them. Only four patients (2.8%) were with conjunctiva chemosis and three patients (2.1%) with lid margin hyperpigmentation. CONCLUSION: Contrary to the belief that latanoprost rarely caused iris hyperpigmentation in yellow-brown eyes, our study showed that 42.8% iris hyperpigmentation did occur, especially after continual use for around 7 months. Higher hyperpigmentation incidence were noted in male than in female patients. This might be due to stronger adrenergic incidence in male than in female patients. Although hypertrichosis and increasing eyelid pigmentation together with iridial pigmentation represented a potentially permanent cosmetic side effect, they are very rare and occurred in no more than 3% in our patients. It is a good way to take Boys-Smith pigment gradation lens for iridial pigmentation grading and for long-term continual evaluation. The doctors should exert great care in differentiating drug-induced iris pigmentation and iris nevi from early stage uveal melanoma.


Assuntos
Anti-Hipertensivos/efeitos adversos , Hiperpigmentação/induzido quimicamente , Doenças da Íris/induzido quimicamente , Prostaglandinas F Sintéticas/efeitos adversos , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Glaucoma de Ângulo Aberto/tratamento farmacológico , Humanos , Hipertricose/induzido quimicamente , Latanoprosta , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
12.
Br J Radiol ; 77(921): 780-1, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15447967

RESUMO

Malignant mesothelioma of the tunica vaginalis is rare, and is usually not diagnosed until surgery is undertaken. Reports on the ultrasound features of this tumour are limited. We present an unusual case with ultrasound features mimicking an adenomatoid tumour.


Assuntos
Tumor Adenomatoide/diagnóstico por imagem , Mesotelioma/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Ultrassonografia Doppler em Cores
13.
Br J Radiol ; 77(915): 250-2, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15020370

RESUMO

Rhabdomyosarcoma is the most common tumour of the lower genitourinary tract in children in the first two decades. Paratesticular rhabdomyosarcoma is associated with a significantly better outcome than lesions elsewhere in the genitourinary tract. Although ultrasound is considered the imaging modality of choice for evaluating intrascrotal pathology, the ultrasound appearance of paratesticular rhabdomyosarcoma has rarely been reported and may be confused with other disease entities such as epididymitis, adenomatoid tumour and leiomyoma. We present the ultrasound features of a paratesticular rhabdomyosarcoma, discussing the clinical features and differential diagnosis.


Assuntos
Neoplasias dos Genitais Masculinos/diagnóstico por imagem , Rabdomiossarcoma/diagnóstico por imagem , Escroto/diagnóstico por imagem , Adolescente , Diagnóstico Diferencial , Humanos , Masculino , Ultrassonografia Doppler em Cores
14.
Radiats Biol Radioecol ; 43(5): 512-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14658280

RESUMO

The large differences in RF safety standards are due to different philosophical approaches to public health standards development, different scientific approaches and interpretations of the scientific data, and different jurisdictions in various countries. In this paper, the origin of these differences is explored. The emphases are on the basic problems of why reported biological effects of RF fields are controversial, and how the general public can be misinformed. While there are differences in approaches and methods, science should converge and not diverge in finding the threshold level for exposure to EMF that is not adverse to human health. As the progress in technology continues and human beings are enjoying an increased quality of life, it is essential for scientists to ensure that safety is not compromised. More importantly, it is the responsibility and moral obligation of scientists and the media to bring "verified" information to the public. Scientists must conduct well-designed studies and to report the results in a clear and detailed manner, so other independent investigators can repeat the study or explore further. Mistakes must be minimized and stopped at the first level of scientific research.


Assuntos
Campos Eletromagnéticos , Saúde Pública , Ondas de Rádio , Animais , Encéfalo/efeitos da radiação , Gatos , Telefone Celular/normas , Células Cultivadas/efeitos da radiação , Eletroencefalografia , Campos Eletromagnéticos/efeitos adversos , Feminino , Humanos , Masculino , Ondas de Rádio/efeitos adversos , Ratos , Valores de Referência , Pesquisa , Segurança/normas , Fatores Socioeconômicos , Temperatura , Organização Mundial da Saúde
15.
Reprod Domest Anim ; 38(6): 470-4, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14629670

RESUMO

BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa.


Assuntos
Fertilização in vitro , Glucose/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Feminino , Glucose/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Gravidez , Taxa de Gravidez
17.
Br J Radiol ; 76(903): 192-4, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12684235

RESUMO

Diabetic mastopathy is a source of confusion with breast carcinoma. The association between mastopathy and Type I diabetes of long duration has been reported, but this clinical condition is poorly recognized since breast examination is not routinely performed in young diabetic patients. Radiologists' awareness of the constellation of findings in diabetic mastopathy may spare patients from undergoing unwarranted surgical biopsies.


Assuntos
Mama/patologia , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Mastite/diagnóstico por imagem , Adulto , Diabetes Mellitus Tipo 1/patologia , Feminino , Fibrose , Humanos , Mamografia , Mastite/patologia , Ultrassonografia
18.
Radiat Res ; 159(4): 550-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12643800

RESUMO

It was reported by others that hands-free accessories increase the absorption of RF energy in a human head compared to a handset alone. The results of this study show that the opposite is observed when proper dosimetric methods are employed. It is pointed out that for correct estimation of the exposure level it is necessary to use appropriate physical and experimental models and measurement instrumentation, following internationally recommended standards. The human phantoms used for measurements involving the hands-free accessories should include the torso; i.e., measurements should not be performed on the head phantom alone. This has a significant impact on the results because the RF energy coupled into the leads of hands-free accessories is strongly attenuated by the body. Numerical simulations using the Finite-Difference Time-Domain (FDTD) method and experimental measurements with a miniature electric-field probe are in good agreement and show a decrease, not an increase, in RF energy exposure in the human head from hands-free accessories.


Assuntos
Telefone Celular , Simulação por Computador , Cabeça/efeitos da radiação , Modelos Anatômicos , Ondas de Rádio , Campos Eletromagnéticos , Desenho de Equipamento , Humanos , Ondas de Rádio/efeitos adversos , Radiometria , Relação Estrutura-Atividade
19.
Bioelectromagnetics ; 24(1): 66-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12483667

RESUMO

Nine small radiation shields made to adhere to the case of mobile phones were tested at 914 and 1880 MHz. Five popular products were tested because advertisements typically claim they are up to 99% effective in blocking radio frequency (RF) radiation emitted from mobile phones. Also, four other conceptually unusual products were tested because advertisements typically claim they emit oscillations that counteract the RF radiation from mobile phones. Each shield was tested on the same mobile phone, and measurements were made to compare the absorption of RF energy in the head with and without each shield attached to the phone. The phone was positioned against a head model, and an automated measurement process was used to determine specific absorption rate (SAR) in the same way it is used at Motorola to test the compliance of mobile phones with respect to human exposure limits. The location of the peak SAR was not observed to change with any of the shields attached to the phone, and the 1 g, peak spatial average SAR did not change by any statistically significant amount. These results indicate the small shields are ineffective in reducing the exposure of the head to RF energy emitted by a mobile phone.


Assuntos
Campos Eletromagnéticos , Proteção Radiológica/instrumentação , Ondas de Rádio , Telefone/instrumentação , Desenho de Equipamento
20.
J Biomed Sci ; 8(3): 270-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11385299

RESUMO

Here we report a quick functional analysis of two mammalian serine/threonine kinases, a serum inducible kinase (Snk) and Homo sapiens hepatoma protein kinase (HsHPK), using Drosophila eye as a model system. We generated transgenic fly lines carrying constructs of both kinases under control of the GAL upstream activating sequence (UAS). Each UAS line was then crossed to a line in which GAL4 expression was driven by one of the following promoters, eyeless (ey), glass or decapentaplegic. Thus, different kinase mutants can be ectopically expressed in a promoter-dependent manner. We observed that the ectopic expression of either the wild-type or active form of Snk driven by the glass promoter resulted in a rough-eye phenotype. Nevertheless, the ectopic expression of HsHPK under the control of the ey promoter resulted in a small-eye phenotype. The results of this study demonstrated that ectopic expression of these two mammalian genes could be achieved by the regulation of Drosophila promoters. In addition, the effects of these ectopically expressed genes on eye development could be an implication of their functions with respect to cell proliferation and differentiation. Thus, Drosophila eye, with the powerful genetic tools and vast information on eye development available, can be a useful system to probe the functions of mammalian genes in the postgenome era.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Olho/embriologia , Olho/metabolismo , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Ligação a DNA/genética , Olho/citologia , Olho/ultraestrutura , Genes de Insetos/genética , Humanos , Proteínas de Insetos/genética , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Mutação/genética , Fenótipo , Regiões Promotoras Genéticas/genética , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Transgenes/genética
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