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1.
Adv Exp Med Biol ; 1194: 475-488, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468564

RESUMO

BACKGROUND: The European Health Risk Assessment Network on Electromagnetic Fields Exposure (EFHRAN) reported in 2012: "Children and adolescents represent the first generation of Europeans to be exposed to diffuse EMF since their conception and birth, thus, they are expected to be more sensitive to these fields." On the other hand, the body's physiologic processes are regulated by the autonomic nervous system (ANS) in a way that warrants further elucidation. OBJECTIVE: Age and duration of exposure are investigated for modifying the variance of the reported effects of mobile/cellular phone call (CPC) on ANS indexed, herein, by the heart rate variability (HRV). METHOD: Five studies targeted to 124 healthy subjects (aged 15.3-28.4 years (24.3 ± 5.2), who have been recorded in supine position before and/or sham versus real exposure (to a CPC lasting 5-32 minutes), are included in this meta-analysis. Age and duration of a CPC are evaluated as predictors in two separate meta-regressions. RESULTS: The meta-analysis identified a heterogeneity I2 = 63.2% for all outcomes and I2 = 65.2% for sympathovagal balance. Thus, we performed meta-regressions: for the sympathovagal balance rather than the combined parameters effect, the goodness of fit model presents significance only for age - the residual sum of squares compared to chi-square distribution (QR) is 4.24 for age (p = 0.12) - while, for minutes of exposure, QR = 8.2805 (p = 0.016). CONCLUSIONS: The sympathovagal balance - indispensible for health/homeostasis maintenance - is strongly predicted by age. Minutes of exposure did not affect overall HRV or sympathovagal balance. The results endorse/validate the EFHRAN 2012 suggestion for future research targeting to youngsters.


Assuntos
Sistema Nervoso Autônomo , Telefone Celular , Campos Eletromagnéticos , Adolescente , Adulto , Fatores Etários , Sistema Nervoso Autônomo/fisiologia , Sistema Nervoso Autônomo/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Adulto Jovem
2.
J Gastroenterol ; 54(11): 994-1006, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31392489

RESUMO

BACKGROUND: Cystic fibrosis transmembrane conductance regulator (CFTR) was recently found in the enteric nervous system, where its role is unclear. We aimed to identify which enteric neuronal structures express CFTR, whether CFTR modulates enteric neurotransmission and if altered CFTR expression is associated with slow transit constipation (STC). METHODS: Immunofluorescence double labeling was performed to localize CFTR with various neuronal and glial cell markers in the human colon. The immunoreactivity (IR) of CFTR and choline acetyltransferase (ChAT) on myenteric plexus of control and STC colon was quantitatively analyzed. In control colonic muscle strips, electrical field stimulation (EFS) evoked contractile responses and the release of acetylcholine (ACh) was measured in the presence of the CFTR channel inhibitor, CFTR(inh)-172. RESULTS: CFTR-IR was densely localized to myenteric ganglia, where it was co-localized with neuronal markers HuC/D and ß-tubulin, and glial marker S-100 but little with glial fibrillary acidic protein. Vesicular ACh transport was almost exclusively co-localized with CFTR, but neurons expressing nitric oxide synthase were CFTR negative. Significant reductions of CFTR-IR (P < 0.01) and ChAT-IR (P < 0.05) were observed on myenteric ganglia of STC compared to control. Pre-treatment of colonic muscle strips with CFTR(inh)-172 (10 µM) significantly inhibited EFS-evoked contractile responses (P < 0.01) and ACh release (P < 0.05). CONCLUSIONS: Co-localization of CFTR-IR with cholinergic markers, inhibition of EFS-induced colonic muscle contractility and ACh release by CFTR(inh)-172 suggest that CFTR modulates enteric cholinergic neurotransmission. The downregulation of CFTR and ChAT in myenteric ganglia of STC correlated with the impaired contractile responses to EFS.


Assuntos
Colo/metabolismo , Constipação Intestinal/fisiopatologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Sistema Nervoso Entérico/metabolismo , Acetilcolina/metabolismo , Colina O-Acetiltransferase/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulação para Baixo , Feminino , Gânglios/metabolismo , Humanos , Contração Muscular/fisiologia , Plexo Mientérico/metabolismo
3.
Radiat Prot Dosimetry ; 178(3): 288-291, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981801
4.
Anat Rec (Hoboken) ; 300(3): 600-613, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27981794

RESUMO

In the present study, a detailed histological description of the female reproductive tract of South American fur seal (Arctophoca australis) pups has been conducted. The uterine tube was covered by cuboidal to columnar epithelium; nerve fibers were present in the mesosalpinx and beneath the muscular layer. The uterus was bipartitus; the endometrial surface of the horns was lined by a simple cuboidal or columnar epithelium with deep tubular glands; caudally ("the transition area"), the epithelium changed to pseudostratified columnar, few tubular glands were present and the myometrium increased in width. A bistratified epithelium internally coated the uterine body, whereas it changed to cylindrical stratified epithelium with a highly vascularized lamina propria and a strong muscular layer in the cervix; no endometrial glands were observed in this region. From the transition area of the uterus to the vagina there were several nerve fibers and ganglia belonging to the uterovaginalis plexus. In the vestibule, hymenal folds were poorly developed; adnexa structures included the major vestibular glands and a neurovascular structure similar to the vestibular bulb. Minor vestibular glands were associated with the clitoris. The skin of the perineum was lined by a keratinized stratified epithelium, pigmented, with sebaceous glands, sweat glands and hair follicles. This is the first detailed histological description of the reproductive tract of South American fur seal pups, including the glandular adnexa and nerve structures. These results contribute to the reproductive biology in Pinniped species, and give a better understanding of the utero-placental perfusion mechanism during diving. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:600-613, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Otárias/anatomia & histologia , Útero/anatomia & histologia , Vagina/anatomia & histologia , Animais , Feminino
5.
Parasitol Res ; 116(1): 1-9, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27785601

RESUMO

It has been hypothesised that mosquitoes [Diptera: Culicidae] may play more of a role in certain cancers than is currently appreciated. Research links 33 infectious agents to cancer, 27 of which have a presence in mosquitoes, and that, in addition, mosquito saliva downregulates the immune system. The objective of this paper is to review the literature on the immune system and cancer-causing infectious agents, particularly those present in mosquitoes, with a view to establishing whether such infectious agents can, in the long run, defeat the immune system or be defeated by it. Many of the viruses, bacteria and parasites recognised by the International Agency for Research on Cancer (IARC) as carcinogenic and suspected by others as being involved in cancer have evolved numerous complex ways of avoiding, suppressing or altering the immune system's responses. These features, coupled with the multiplicity and variety of serious infectious agents carried by some species of mosquitoes and the adverse effects on the immune system of mosquito saliva, suggest that post-mosquito bite the immune system is likely to be overwhelmed. In such a situation, immunisation strategies offer little chance of cancer prevention, unless a single or limited number of critical infectious agents can be isolated from the 'mosquito' cocktail. If that proves to be impossible cancer prevention will, therefore, if the hypothesis proves to be correct, rest on the twin strategies of environmentally controlling the mosquito population and humans avoiding being bitten. The latter strategy will involve determining the factors that demark those being bitten from those that are not.


Assuntos
Culicidae , Interações Hospedeiro-Patógeno/imunologia , Sistema Imunitário , Mosquitos Vetores , Neoplasias , Animais , Culicidae/imunologia , Culicidae/microbiologia , Culicidae/parasitologia , Culicidae/virologia , Humanos , Mosquitos Vetores/imunologia , Mosquitos Vetores/microbiologia , Mosquitos Vetores/parasitologia , Mosquitos Vetores/virologia , Neoplasias/imunologia , Neoplasias/microbiologia , Neoplasias/parasitologia , Neoplasias/virologia
6.
Electromagn Biol Med ; 35(4): 393-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27355805

RESUMO

In August 2003, 48-year-old JS of Colorado, USA, a fitness therapist and sports nutritionist, contracted neuroinvasive West Nile virus which left her with disabilities due to spinal axonal damage.In August 2014, she suddenly developed symptoms very much like her acute West Nile infection 11 years ago, including focal seizures, ataxia, vertigo and headaches. Her blood count looked normal so there was no obvious infection. What struck her as odd was that when she left her apartment for any length of time, the symptoms stopped. She found out that a new type of wireless modem, enabled for both personal use and functioning as a public hotspot designed to reach up to 100 m, had been installed in the flat under hers.Her neighbor replaced the modem with a router without the hotspot feature. After that, the seizures stopped immediately, and the other symptoms faded gradually, after which she was fine and again could sleep well. Later, when another activated hotspot was installed in an adjacent flat, JS once again noticed symptoms.A possible association between electrohypersensitivity, myelin integrity and exposure to low-intensity radiofrequency electromagnetic fields (RF-EMF) typical in the modern world has recently been proposed. Since the West Nile virus attacks both the nerve cells and the glial ones, one explanation to the above observed case effects is that the initial virus attack and the wireless modem's RF-EMF affect the nervous system through the very same, or similar, avenues, and maybe both via the oligodendrocytes.


Assuntos
Doenças Desmielinizantes/etiologia , Exposição à Radiação/efeitos adversos , Tecnologia sem Fio , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade
7.
Electromagn Biol Med ; 35(2): 103-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25535695

RESUMO

In 2002, a paper was published that highlighted the strong correlation noticed between melanoma incidence and the number of surrounding frequency modulation (FM) transmitters in the Nordic countries since 1955. In the report the development of future numbers of melanoma cases in Estonia were estimated since they got the FM broadcasting system rolled out not until 1992. Here, we report what happened since then in Estonia regarding melanoma cases per year. We also comment on the recent development in the Nordic countries, which is not very reassuring from a public health point of view. The last 10 years of melanoma incidence trends, increasing at an exponential rate, suggest that responsible authorities now need to consider possible influences also from other radiation sources in addition to UV radiation from the sun.


Assuntos
Previsões , Melanoma/epidemiologia , Humanos , Melanoma/etiologia , Raios Ultravioleta/efeitos adversos
8.
Rev Environ Health ; 30(4): 311-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26613327

RESUMO

In Sweden, electrohypersensitivity is recognized as a functional impairment which implies only the environment as the culprit. The Swedish view provides persons with this impairment a maximal legal protection, it gives them the right to get accessibility measures for free, as well as governmental subsidies and municipality economic support, and to provide them with special Ombudsmen (at the municipality, the EU, and the UN level, respectively), the right and economic means to form disability organizations and allow these to be part of national and international counterparts, all with the simple and single aim to allow persons with the functional impairment electrohypersensitivity to live an equal life in a society based on equality. They are not seen as patients, the do not have an overriding medical diagnosis, but the 'patient' is only the inferior and potentially toxic environment. This does not mean that a subjective symptom of a functionally impaired can not be treated by a physician, as well as get sick-leave from their workplace as well as economic compensation, and already in the year 2000 such symptoms were identified in the Internal Code of Diagnoses, version 10 (ICD-10; R68.8/now W90), and have been since. But the underlying cause still remains only the environment.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Meio Ambiente , Hipersensibilidade/fisiopatologia , Hipersensibilidade/etiologia , Suécia
9.
Rev Environ Health ; 30(4): 323-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26613328

RESUMO

Our environment is now permeated by anthropogenic radiofrequency electromagnetic radiation, and individuals of all ages are exposed for most of each 24 h period from transmitting devices. Despite claims that children are more likely to be vulnerable than healthy adults to unwanted effects of this exposure, there has been no recent examination of this, nor of comparative risk to the elderly or ill. We sought to clarify whether research supports the claim of increased risk in specific age-groups. First, we identified the literature which has explored age-specific pathophysiological impacts of RF-EMR. Natural life-span changes relevant to these different impacts provides context for our review of the selected literature, followed by discussion of health and well-being implications. We conclude that age-dependent RF-EMR study results, when considered in the context of developmental stage, indicate increased specific vulnerabilities in the young (fetus to adolescent), the elderly, and those with cancer. There appears to be at least one mechanism other than the known thermal mechanism causing different responses to RF-EMR depending upon the exposure parameters, the cell/physiological process involved, and according to age and health status. As well as personal health and quality-of-life impacts, an ageing population means there are economic implications for public health and policy.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Ondas de Rádio/efeitos adversos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Rev Environ Health ; 30(4): 337-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26613329

RESUMO

Chronic diseases and illnesses associated with unspecific symptoms are on the rise. In addition to chronic stress in social and work environments, physical and chemical exposures at home, at work, and during leisure activities are causal or contributing environmental stressors that deserve attention by the general practitioner as well as by all other members of the health care community. It seems certainly necessary now to take "new exposures" like electromagnetic field (EMF) into account. Physicians are increasingly confronted with health problems from unidentified causes. Studies, empirical observations, and patient reports clearly indicate interactions between EMF exposure and health problems. Individual susceptibility and environmental factors are frequently neglected. New wireless technologies and applications have been introduced without any certainty about their health effects, raising new challenges for medicine and society. For instance, the issue of so-called non-thermal effects and potential long-term effects of low-dose exposure were scarcely investigated prior to the introduction of these technologies. Common EMF sources include Wi-Fi access points, routers and clients, cordless and mobile phones including their base stations, Bluetooth devices, ELF magnetic fields from net currents, ELF electric fields from electric lamps and wiring close to the bed and office desk. On the one hand, there is strong evidence that long-term-exposure to certain EMF exposures is a risk factor for diseases such as certain cancers, Alzheimer's disease and male infertility. On the other hand, the emerging electromagnetic hypersensitivity (EHS) is more and more recognized by health authorities, disability administrators and case workers, politicians, as well as courts of law. We recommend treating EHS clinically as part of the group of chronic multisystem illnesses (CMI) leading to a functional impairment (EHS), but still recognizing that the underlying cause remains the environment. In the beginning, EHS symptoms often occur only occasionally, but over time they may increase in frequency and severity. Common EHS symptoms include headaches, concentration difficulties, sleeping problems, depression, lack of energy, fatigue and flu-like symptoms. A comprehensive medical history, which should include all symptoms and their occurrences in spatial and temporal terms and in the context of EMF exposures, is the key to the diagnosis. The EMF exposure can be assessed by asking for typical sources like Wi-Fi access points, routers and clients, cordless and mobile phones and measurements at home and at work. It is very important to take the individual susceptibility into account. The primary method of treatment should mainly focus on the prevention or reduction of EMF exposure, that is, reducing or eliminating all sources of EMF at home and in the workplace. The reduction of EMF exposure should also be extended to public spaces such as schools, hospitals, public transport, and libraries to enable persons with EHS an unhindered use (accessibility measure). If a detrimental EMF exposure is reduced sufficiently, the body has a chance to recover and EHS symptoms will be reduced or even disappear. Many examples have shown that such measures can prove effective. Also the survival rate of children with leukemia depends on ELF magnetic field exposure at home. To increase the effectiveness of the treatment, the broad range of other environmental factors that contribute to the total body burden should also be addressed. Anything that supports a balanced homeostasis will increase a person's resilience against disease and thus against the adverse effects of EMF exposure. There is increasing evidence that EMF exposure has a major impact on the oxidative and nitrosative regulation capacity in affected individuals. This concept also may explain why the level of susceptibility to EMF can change and why the number of symptoms reported in the context of EMF exposures is so large. Based on our current understanding, a treatment approach that minimizes the adverse effects of peroxynitrite - as has been increasingly used in the treatment of multisystem disorders - works best. This EMF Guideline gives an overview of the current knowledge regarding EMF-related health risks and provides concepts for the diagnosis and treatment and accessibility measures of EHS to improve and restore individual health outcomes as well as for the development of strategies for prevention.

11.
Sci Rep ; 5: 14914, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26456585

RESUMO

In the present study we analyze the role of polarization in the biological activity of Electromagnetic Fields (EMFs)/Electromagnetic Radiation (EMR). All types of man-made EMFs/EMR - in contrast to natural EMFs/EMR - are polarized. Polarized EMFs/EMR can have increased biological activity, due to: 1) Ability to produce constructive interference effects and amplify their intensities at many locations. 2) Ability to force all charged/polar molecules and especially free ions within and around all living cells to oscillate on parallel planes and in phase with the applied polarized field. Such ionic forced-oscillations exert additive electrostatic forces on the sensors of cell membrane electro-sensitive ion channels, resulting in their irregular gating and consequent disruption of the cell's electrochemical balance. These features render man-made EMFs/EMR more bioactive than natural non-ionizing EMFs/EMR. This explains the increasing number of biological effects discovered during the past few decades to be induced by man-made EMFs, in contrast to natural EMFs in the terrestrial environment which have always been present throughout evolution, although human exposure to the latter ones is normally of significantly higher intensities/energy and longer durations. Thus, polarization seems to be a trigger that significantly increases the probability for the initiation of biological/health effects.


Assuntos
Membrana Celular/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Canais Iônicos/efeitos da radiação , Radiação Eletromagnética , Desenho de Equipamento , Humanos , Ativação do Canal Iônico/efeitos da radiação , Fatores de Tempo
12.
Biomed Res Int ; 2015: 607053, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26346766

RESUMO

We examined whether exposures to mobile phone radiation in biological/clinical experiments should be performed with real-life Electromagnetic Fields (EMFs) emitted by commercially available mobile phone handsets, instead of simulated EMFs emitted by generators or test phones. Real mobile phone emissions are constantly and unpredictably varying and thus are very different from simulated emissions which employ fixed parameters and no variability. This variability is an important parameter that makes real emissions more bioactive. Living organisms seem to have decreased defense against environmental stressors of high variability. While experimental studies employing simulated EMF-emissions present a strong inconsistency among their results with less than 50% of them reporting effects, studies employing real mobile phone exposures demonstrate an almost 100% consistency in showing adverse effects. This consistency is in agreement with studies showing association with brain tumors, symptoms of unwellness, and declines in animal populations. Average dosimetry in studies with real emissions can be reliable with increased number of field measurements, and variation in experimental outcomes due to exposure variability becomes less significant with increased number of experimental replications. We conclude that, in order for experimental findings to reflect reality, it is crucially important that exposures be performed by commercially available mobile phone handsets.


Assuntos
Telefone Celular , Ondas de Rádio/efeitos adversos , Estresse Fisiológico , Animais , Humanos
13.
Artigo em Inglês | MEDLINE | ID: mdl-25205214

RESUMO

Myelin provides the electrical insulation for the central and peripheral nervous system and develops rapidly in the first years of life, but continues into mid-life or later. Myelin integrity is vital to healthy nervous system development and functioning. This review outlines the development of myelin through life, and then considers the evidence for an association between myelin integrity and exposure to low-intensity radiofrequency electromagnetic fields (RF-EMFs) typical in the modern world. In RF-EMF peer-reviewed literature examining relevant impacts such as myelin sheath, multiple sclerosis, and other myelin-related diseases, cellular examination was included. There are surprisingly little data available in each area, but considered together a picture begins to emerge in RF-EMF-exposed cases: (1) significant morphological lesions in the myelin sheath of rats; (2) a greater risk of multiple sclerosis in a study subgroup; (3) effects in proteins related to myelin production; and (4) physical symptoms in individuals with functional impairment electrohypersensitivity, many of which are the same as if myelin were affected by RF-EMF exposure, giving rise to symptoms of demyelination. In the latter, there are exceptions; headache is common only in electrohypersensitivity, while ataxia is typical of demyelination but infrequently found in the former group. Overall, evidence from in vivo and in vitro and epidemiological studies suggests an association between RF-EMF exposure and either myelin deterioration or a direct impact on neuronal conduction, which may account for many electrohypersensitivity symptoms. The most vulnerable are likely to be those in utero through to at least mid-teen years, as well as ill and elderly individuals.


Assuntos
Doenças Desmielinizantes/etiologia , Campos Eletromagnéticos/efeitos adversos , Bainha de Mielina/efeitos da radiação , Ondas de Rádio/efeitos adversos , Animais , Humanos , Bainha de Mielina/fisiologia
14.
Electromagn Biol Med ; 33(4): 282-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23977878

RESUMO

Society is confronted with an increasing number of applications making use of wireless communication. We also notice an increasing awareness about potentially harmful effects of the related electromagnetic fields on living organisms. At present, it is not realistic to expect that wireless communication will decrease or disappear within the near future. That is why we currently are investigating the mechanisms behind these effects and the effectiveness of possible solutions. In order to be efficient and effective, we designed and validated a fast and easy test on ants - these insects being used as a biological model - for revealing the effect of wireless equipments like mobile phones, smartphones, digital enhanced cordless telephone (DECT) phones, WiFi routers and so on. This test includes quantification of ants' locomotion under natural conditions, then in the vicinity of such wireless equipments. Observations, numerical results and statistical results allow detecting any effect of a radiating source on these living organisms.


Assuntos
Formigas/efeitos da radiação , Radiação Eletromagnética , Tecnologia sem Fio/instrumentação , Animais , Telefone Celular , Computadores , Locomoção
15.
Cancers (Basel) ; 5(1): 184-204, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24310359

RESUMO

Skin melanoma rates have been increasing for a long time in many Western countries. The object of this study was to apply modern problem-solving theory normally used to clear industrial problems to search for roots and causes of this medical question. Increasing cancer rates can be due to too many cell damage incidents or to too few repairs. So far, it has been assumed that the melanoma epidemic mainly is caused by increasing sun tanning habits. In order to explore this problem in more detail, we used cancer statistics from several countries over time and space. Detailed analysis of data obtained and a model study to evaluate the effects from increased damages or decreased repairs clearly indicate that the main reason behind the melanoma problem is a disturbed immune system. The possibility to introduce efficient corrective actions is apparent.

16.
Anat Rec (Hoboken) ; 296(10): 1658-63, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23959768

RESUMO

The aim of this study was to analyze the morphometric characteristics of ovarian follicles and their distribution in the ovarian cortex in South American fur seal pups (Arctophoca australis). Samples were obtained from animals stranded in the Uruguayan Atlantic coast. Ovaries were dissected, fixed, weighed, and processed by standard histological techniques. Ovarian weight increased with pup age and body length. There was an increase in the diameter of the oocytes (22.24 ± 0.6 to 68.2 ± 5.3 µm), the nuclei (10.04 ± 0.2 to 20.7 ± 1.6 µm), and follicles (30.4 ± 1.2 to 252.6 ± 53.6 µm) of type 1 to type 5 follicles; there was a wide range of variation in the diameter of follicle type 4 and 5. Granulosa layer thickness increased between follicles type 3 and 4, whereas between type 4 and 5 there was a reduction. Thecal layer from follicles type 3 and 4 consisted of 1-2 layers of cells, whereas type 5 showed an increase in thickness (3.13 ± 0.3 to 13.8 ± 5.2 µm). Follicles type 1 and 2 occupied superficial regions within the ovarian cortex while the remaining follicles had a deeper location. These results provide a basis for comparison with females of other age categories as well as follicular dynamics studies in South American fur seals.


Assuntos
Otárias/anatomia & histologia , Folículo Ovariano/anatomia & histologia , Animais , Animais Recém-Nascidos , Feminino , Microscopia de Polarização , América do Sul
17.
PLoS One ; 8(6): e62663, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23750202

RESUMO

PURPOSE: To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF dosimetry and bioactivity assessment. METHODS: We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposure and biological effect. RESULTS: WE FIND THAT: a) The energy absorbed by living matter during exposure to environmentally accounted EMFs is normally well below the thermal level. b) All existing methods for SAR estimation, especially those based upon tissue conductivity and internal electric field, have serious deficiencies. c) The only method to estimate SAR without large error is by measuring temperature increases within biological tissue, which normally are negligible for environmental EMF intensities, and thus cannot be measured. CONCLUSIONS: SAR actually refers to thermal effects, while the vast majority of the recorded biological effects from man-made non-ionizing environmental radiation are non-thermal. Even if SAR could be accurately estimated for a whole tissue, organ, or body, the biological/health effect is determined by tiny amounts of energy/power absorbed by specific biomolecules, which cannot be calculated. Moreover, it depends upon field parameters not taken into account in SAR calculation. Thus, SAR should not be used as the primary dosimetric quantity, but used only as a complementary measure, always reporting the estimating method and the corresponding error. Radiation/field intensity along with additional physical parameters (such as frequency, modulation etc) which can be directly and in any case more accurately measured on the surface of biological tissues, should constitute the primary measure for EMF exposures, in spite of similar uncertainty to predict the biological effect due to non-linearity.


Assuntos
Campos Eletromagnéticos , Radiobiologia/métodos , Radiometria/métodos , Absorção , Dinâmica não Linear , Temperatura , Fatores de Tempo
18.
Pathophysiology ; 19(3): 185-91, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22841384

RESUMO

The development and implementation of electricity in the modern society have facilitated the survival of mankind in the present, modern ages. However, the health consequences of introducing electricity into the society are poorly studied. Studies of artificial light and non-ionizing radiation are generally low priorities on the agenda of public health organizations, and the reported existing data indicate that there are several unanswered questions to whether humans are negatively affected in electrified environments. This article discusses the potential aspects of the impact of electricity on human health and brain function and introduces a hypothesis. The article furthermore discusses the disturbance of sleep patterns caused by electrified environments, and the increasing absence of natural stimuli to the human brain causing chronic 'digital stress' facilitating pathophysiological development. A significant need to study adverse health effects from non-ionizing radiation and synthetic luminous environments from an environmental toxicological perspective is definitely urged.

19.
Arch Dermatol Res ; 304(10): 781-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22660851

RESUMO

Peripheral nerve fibres are often increased in lesional skin of atopic dermatitis (AD) patients. We attempted to study nerve fibre profiles, using PGP 9.5 as neuronal marker, in early AD lesions in 10 patients, as compared to non-lesional skin in the same patients and skin from healthy controls. The number of PGP 9.5-positive nerve fibre profiles was not different in the biopsies taken from normal-looking AD skin and healthy controls. The total number of PGP 9.5-positive nerve fibre profiles in the whole skin sections was higher in both the epidermis and the dermis in the group of skin biopsies taken from early lesions of AD patients. Further, the number of epidermal PGP 9.5-positive dendritic cells was increased in AD skin. It seems reasonable that PGP 9.5-positive nerve fibres and PGP 9.5-positive dendritic cells have pathological roles in AD. The findings might serve as a basis for further studies in evaluating novel diagnostic and therapeutic approaches.


Assuntos
Dermatite Atópica/enzimologia , Fibras Nervosas/enzimologia , Pele/inervação , Ubiquitina Tiolesterase/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Dermatite Atópica/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologia , Adulto Jovem
20.
ISRN Oncol ; 2012: 687298, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22530149

RESUMO

Objective. To develop a conceptual model for lung cancer rates to describe and quantify observed differences between Sweden and USA contra Japan. Method. A two-parameter lognormal distribution was used to describe the lung cancer rates over time after a 1-year period of smoking. Based on that risk function in combination with smoking prevalence, the calculated age-standardized rates were adjusted to fit reported data from Japan, Sweden, and the USA by parameter variation. Results. The risk of lung cancer is less in Japan than in Sweden and in the USA at the same smoking prevalence and intensity. Calculated age-specific rates did also fit well to reported rates without further parameter adjustments. Conclusions. This new type of cancer model appears to have high degree of predictive value. It is recommended that data from more countries are studied to identify important life-style factors related to lung cancer.

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