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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The effect of maternal nicotine exposure on the alveolar wall composition during the phases of lung development

Adonis, Jihaan January 2015 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Cigarette smoking is one of the foremost causes of chronic obstructive pulmonary diseases such as emphysema and chronic bronchitis, and although it is the most preventable causes of death, it accounts for approximately 6 million deaths worldwide each year. Cigarette smoking during pregnancy and lactation remains one of the primary modifiable risk factors for undesirable fetal, obstetrical, and developmental outcomes. Consequently, the offspring of the smoking mother is exposed to nicotine via the blood and the milk of the mother. As a result, nicotine interacts with the developing offspring and therefore interferes with normal fetal lung development. Maternal smoking during gestation and lactation has been associated with both short and long term health risks ranging from intrauterine growth restriction to physiological abnormalities. Maternal smoking has also been strongly linked to an increased risk for pulmonary diseases and respiratory morbidity in the offspring of the smoking mother. The main objectives of this study were to determine the effects of maternal nicotine exposure during gestation and lactation on the alveolar wall composition during lung development in the offspring; if maternal nicotine exposure during gestation and lactation induces premature cellular senescence in the lungs of the offspring; to clarify the role of pulmonary fibroblasts in premature senescence; and to establish whether tomato juice supplementation will prevent premature aging in the lungs of rats that were exposed to nicotine via the placenta and mother’s milk. From the data generated in this study it was evident that maternal nicotine exposure during gestation and lactation compromises the gas exchange function of the lungs of the F1 offspring. This was prevented by supplementing the mother’s diet with tomato juice which is then received by the offspring via the placenta and mother’s milk. This is conceivably achieved by maintaining the oxidant-anti-oxidant ratio of the mother and of the developing fetus and neonate, thereby averting premature senescence caused by nicotine exposure. Moreover, the present study also demonstrates that a decrease in fibroblast density is associated with emphysematous-like lesions in the lungs of the nicotine exposed F1 progeny. Since pulmonary fibroblasts are chief contributors to the extracellular matrix of the lungs, involved in alveolar multiplication and regeneration; premature aging or cessation of the metabolically active fibroblasts largely contributes to diminished lung structure and function.
12

Maternal occupational exposure to extremely low frequency magnetic fields and risk of brain tumors in offspring

Li, Pei Zhi. January 2008 (has links)
Background: The causes of childhood brain tumors (CBT) are essentially unknown. Exposure to extremely low frequency magnetic fields (ELF-MF) (3-3000Hz) is an ubiquitous part of modern life. However, very few studies have investigated the possible effect of maternal occupational ELF-MF exposure on CBT and the available findings are inconsistent across studies. / Methods: We examined the role of maternal occupational exposure to ELF-MF shortly before and during pregnancy on the incidence of childhood brain tumors. A total of 548 incident cases and 760 healthy controls recruited between 1980 and 2002 from two Canadian provinces (Quebec and Ontario) were included and their mothers were interviewed. Tumors were classified as astroglial tumors, primitive neuroectodermal tumors (PNET), and other gliomas. Quantitative occupational ELF-MF exposure in microtesla units was estimated using individual exposure estimations or a job exposure matrix. We used three metrics to analyze exposure: cumulative, average, and maximum level attained. / Results: Using the average exposure metric measured before conception, an increased risk was observed for astroglial tumors (OR=1.5, and 95% CI=1.0-2.4). During the entire pregnancy period, a significantly increased risk was observed for astroglial tumors as well as for all childhood brain tumors with the average metric (OR=1.6, 95% CI=1.1-2.5 and OR=1.5; 95% CI=1.1-2.2, respectively). Based on job titles, a two-fold risk increase was observed for astroglial tumors (OR=2.3, 95% CI=0.8-6.3) and for all childhood brain tumors (OR=2.3, 95% CI=1.0-5.4) among sewing machine operators. / Conclusion: Results are suggestive of a possible association between maternal occupational ELF-MF exposure and certain brain tumors in their offspring. / Keywords: brain tumors, occupational exposures, maternal exposures, magnetic fields, childhood cancer, job exposure matrix
13

Measures of maternal tobacco smoke exposure and foetal growth

Almeida, Nisha. January 2007 (has links)
Objective. Most biomarker studies of maternal smoking have been based on a single blood or urinary cotinine value, which is inadequate in capturing maternal tobacco exposure over the entire pregnancy. This thesis used maternal hair biomarkers to investigate the association between maternal active and passive smoking, and birthweight for gestational age (BW for GA). / Methods. Subjects were 444 term controls drawn from 5,337 participants of a multi-centre nested case-control study of preterm birth in Montreal. Maternal hair, collected after delivery, was measured for average nicotine and cotinine concentration across the pregnancy, assuming hair growth of 1 cm/month. The BW for GA z-score used Canadian population-based standards. Multiple linear regression was used to assess effects on the z-score, after controlling for potential confounders. / Results. In regression models for maternal active smoking analysis, the addition of hair nicotine to models containing either self-report or hair cotinine or both self-report and cotinine explained significantly more variance in the BW for GA z-score (p=0.009, p=0.017, and p=0.033, respectively). In maternal passive smoking analysis, no significant effect of ETS on BW for GA was found using hair biomarkers. / Conclusion. These results indicate that hair biomarkers are sensitive tools capable of predicting reductions in birthweight for maternal active smoking. The stronger results obtained for nicotine are reflective of the fact that hair nicotine is a better measure of maternal smoking, but it could also suggest that nicotine plays an aetiologic role in affecting foetal growth.
14

Investigação da ação disruptora da deltametrina sobre a tireoide e função hipofisária de ratos (Gerações F1 E F2) / Investigation of disruptive action of deltamethrin on thyroid and pituitary function in rats (F1 and F2 generation)

Santos, Julio Cezar dos 09 March 2018 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-05-24T19:14:51Z No. of bitstreams: 2 Julio Cezar dos Santos.pdf: 1442616 bytes, checksum: dc9859e73b5e29a7f64edb68bb2c545e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-24T19:14:51Z (GMT). No. of bitstreams: 2 Julio Cezar dos Santos.pdf: 1442616 bytes, checksum: dc9859e73b5e29a7f64edb68bb2c545e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-09 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Estado do Paraná (FA) / Little is known about chronic exposure to pyrethroids; however, contact with this type of substance is common and has often been found in breast milk and urine, in addition to environmental detections that have sometimes been related to diverse biological changes. The present study aims to evaluate the possible disruptive actions of deltamethrin in low doses on the thyroid, a hyposal function in the development in transgenerations of rats. For this, 6 non-consanguine adult, Wistar albino rats were used, provided by the Central Vivarium of the State University of the West of Paraná (UNIOESTE). All the experimental procedures were followed the protocol evaluated and approved by the Committee of Ethics in the Use of Animals of the State University of the West of Paraná (CEUA / UNIOESTE). The treatment group received a daily intraperitoneal injection of deltamethrin at the concentration of 0.01 mg.kg-1 of body weight between the 8th and 14th day of pregnancy, the control group received canola oil. Next generations (F1 and F2) did not receive treatment and were evaluated for growth and development, by birth weight, Lee index and weight at euthanasia. After euthanasia, the pituitary gland was isolated and weighted. A positive correlation was observed between weight variation throughout pregnancy and the number of pups born. There was no difference between the treatment and control groups in the birth weight of first generation rats (F1). The birth weight of the 2nd generation (F2) rats from the treated rats was lower in comparison with the weight of those from the control rats. When assessing weight, Lee's index and pituitary weight at euthanasia, there were no statistical differences between control and treatment. Females had larger pituitary glands when compared to males. We concluded that deltamethrin interferes with the birth weight of rats and this interference follows a transgenerational pattern of clinical implication. / Pouco se sabe sobre a exposição crônica a piretroides, apesar disso, o contato com esse tipo de substância é comum e frequentemente têm-se verificado sua presença no leite materno e urina, além das detecções ambientais que por algumas vezes foram relacionadas com alterações biológicas diversificadas. O presente estudo visa avaliar as possíveis ações disruptoras da deltametrina em baixas doses sobre a tireoide, função hiposária no desenvolvimento em transgerações de ratos. Para isso, foram utilizados seis ratos adultos não consanguíneos, albinos, da linhagem Wistar, fornecidos pelo Biotério Central da Universidade Estadual do Oeste do Paraná (UNIOESTE). Todos os procedimentos experimentais seguiram em concordância com protocolo avaliado e aprovado pelo Comitê de Ética no Uso de Animais da Universidade Estadual do Oeste do Paraná (CEUA/UNIOESTE). O grupo Tratamento recebeu uma injeção intraperitoneal diária de deltametrina na concentração de 0,01 mg.kg-1 de peso corpóreo, entre o 8º e 14º dia de prenhez; o grupo Controle recebeu óleo de canola. As gerações seguintes (F1 e F2) não receberam tratamento e foram avaliadas quanto ao crescimento e desenvolvimento, através do peso ao nascer, índice de Lee e peso na eutanásia. Após a eutanásia, a glândula hipófise foi isolada e pesada. Foi observada uma correlação positiva entre variação de peso - ao longo da prenhez - e o número de filhotes nascidos. Não houve diferença entre os grupos Tratamento e Controle, no peso do nascimento dos ratos da primeira geração (F1). O peso de nascimento dos ratos da 2ª geração (F2), oriundos das ratas tratadas, foi menor, comparado ao peso daqueles oriundos de ratas controle. Ao avaliar o peso, o índice de Lee e o peso da hipófise na eutanásia, não houve diferenças estatísticas entre controle e tratamento. As fêmeas apresentaram hipófises maiores, se comparadas aos machos. Concluímos que a deltametrina interfere no peso de nascimento dos ratos e esta interferência obedece a um padrão transgeracional de implicação clínica.
15

Maternal occupational exposure to extremely low frequency magnetic fields and risk of brain tumors in offspring

Li, Pei Zhi. January 2008 (has links)
No description available.
16

Measures of maternal tobacco smoke exposure and foetal growth

Almeida, Nisha Dativa January 2007 (has links)
No description available.
17

Parental demographic risk factors and occupational exposure to ionizing radiation for achondroplasia, thanatophoric and autosomal deletions in Texas, 1996-2002 /

Vo, Tuan M. Waller, Kim. January 2006 (has links)
Thesis (Ph. D.)--University of Texas Health Science Center at Houston, School of Public Health, 2006. / Includes bibliographical references (leaves 100-107).
18

Occupational exposure to pesticides and risk of leukemia among offspring in Costa Rica /

Monge, Patricia, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
19

Uticaj organofosfornih pesticida na pojavu nespuštenog testisa / The impact of organophosphorus pesticides on the occurrence of the undescended testis

Fratrić Ivana 31 October 2019 (has links)
<p>Nespu&scaron;teni testis predstavlja odsustvo testisa u skrotumu sa jedne ili obe strane. Faktori rizika za pojavu nespu&scaron;tenog testisa obuhvataju genetsku predispoziciju, prevremeno rođenje, nisku porođajnu masu i prenatalnu izloženost endokrinim disruptorima ili duvanskom dimu. Endokrini disruptori se defini&scaron;u kao egzogene supstance koje imaju uticaj na homeostazu organizma i proizvodnju reproduktivnih hormona. U ovoj grupi nalaze se organofosforni pesticidi koji se &scaron;iroko upotrebljavaju u poljoprivredi. Većina organofosfornih pesticida ima antiandrogeni uticaj i uz činjenicu da živimo u pretežno agrarnoj sredini predmet su na&scaron;eg interesovanja. Cilj istraživanja je da se utvrdi razlika u izloženosti organofosfornim pesticidima kori&scaron;ćenjem upitnika kreiranog po modelu standardizovanog Evropskog upitnika QLK 4-1999-01422 kod osoba koje su rodile zdravu mu&scaron;ku decu i osoba koje su rodile decu sa nespu&scaron;tenim testisom. Pored toga, cilj istraživanja je i da se odredi i uporedi vrednost metabolita organofosfornih pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat i dietilditiofosfat) u urinu majki koje su rodile mu&scaron;ku decu sa nespu&scaron;tenim testisima i majki koje su rodile zdravu mu&scaron;ku decu. Metodologija: Rad je radomizovano, prospektivno, kliničko istraživanje sprovedeno na Klinici za ginekologiju i aku&scaron;erstvo Kliničkog centra Vojvodine i Katedri za farmakologiju i toksikologiju Medicinskog fakulteta, Univerziteta u Novom Sadu. U kliničko istraživanje uključeno je 50 porodilja koje su rodile mu&scaron;ku decu sa nespu&scaron;tenim testisima (eksperimentalna grupa) i 53 porodilje koje su rodile zdravu mu&scaron;ku decu (kontrolna grupa) u periodu od oktobra 2012. godine do aprila 2018. godine. Tokom boravka u porodili&scaron;tu ispitanice su popunjavale upitnik o navikama nakon čega im je uzet uzorak urina radi analiziranja nivoa metabolita OF pesticida. Uzorci urina su pripremljeni metodom koju su opisali Wu i saradnici 2010. godine, a potom analizirani na gasnom hromatografu masenom spektrofotometaru marke Agilent 7890A. Rezultati: Ispitivane grupe se ne razlikuju po starosti ispitanica (prosečna starost kontrolne grupe 29,41 &plusmn; 5,58 godina, a eksperimentalne 30,54 &plusmn; 4,87 godina). U obe grupe prosečno je ispitanicama ovo bila druga trudnoća. Ispitanice se nisu razlikovale ni po načinu porođaja. Prosečna gestacijska nedelja trudnoće na porođaju iznosila je 39,45 &plusmn; 1,38 nedelja za kontrolnu grupu i 39,20 &plusmn; 1,38 nedelja za eksperimentalnu grupu, a porođajna masa novorođenčeta 3527,30 &plusmn; 470,16 g u kontrolnoj grupi i 3404,37 &plusmn; 508,20 g u eksperimentalnoj grupi. Statistički značajna razlika postoji u odnosu na mesto stanovanja (50,9 % ispitanica kontrolne grupe i 77,6 % ispitanica eksperimentalne grupe žive u gradu), jedinicu stanovanja (67,9 % kontrolne i 45,7 % ispitanica eksperimentalne grupe žive u kući) i načinu začeća (6 % ispitanica eksperimentalne i 1,9 % ispitanica kontrolne grupe prijavilo je IVF kao način začeća). Skoro polovina ispitanica obe grupe su pu&scaron;ači, a njih 32,7 % kontrolne grupe i 38,8 % eksperimentalne pu&scaron;ile su i tokom trudnoće. Izloženost pesticidima prijavilo je 50,9 % ispitanica kontrolne i 44 % ispitanica eksperimentalne grupe, a profesionalnu izloženost prijavilo je 3 ispitanice kontrolne i 2 ispitanice eksperimentalne grupe. Ispitanice se ne razlikuju ni po poreklu voća i povrća koje konzumiraju, kao ni po vrsti voća koje su konzumirale tokom trudnoće. Prosečne izmerene vrednosti DMF u kontrolnoj grupi iznose 5,604 &plusmn; 6,103 ug/L, a u eksperimentalnoj 4,815 &plusmn; 6,729 ug/L. Izmerene vrednosti DEF u kontrolnoj grupi su 0,408 &plusmn; 0,447 ug/L, a u eksperimentalnoj 0,461 &plusmn; 0,593 ug/L. Nivo DMDTF u kontrolnoj grupi bio je 0,431 &plusmn; 0,508 ug/L, a u eksperimentalnoj 0,547 &plusmn; 0570 ug/L, a DETF 0,403 &plusmn; 0,606 ug/L u kontrolnoj i 0,529 &plusmn; 0,725 ug/L u eksperimentalnoj grupi. Ni jedan metabolit ne pokazuje statistički značajnu razliku u ispitivanim grupama. Slične vrednosti dobijene su i za vrednosti korigovane za nivo kreatinina. Univarijantna regresiona analiza pokazala je da ispitanice koje žive u gradu imaju 3,3 puta veće &scaron;anse da rode dete sa nespu&scaron;tenim testisom, a one koje žive u stanu imaju 2,5 puta veće &scaron;anse za isti ishod. Statistički značajna razlika primećena je u nivou DEDTF u zavisnosti od starosti ispitanica i jedinici stanovanja. Vi&scaron;e vrednosti DETF dobijene su kod ispitanica koje su bile na hormonskoj terapiji tokom trudnoće. Ispitanice koje su prijavile da su bile izložene pesticidima tokom trudnoće u urinu su imale statistički značajno vi&scaron;e vrednosti DMDTF u odnosu na ispitanice koje su se izjasnile da nisu bile izložene pesticidima. Slični rezultati za vrednost DEDTF dobijeni su kod ispitanica koje su se izjasnile da poseduju kućne ljubimce. Statistički vi&scaron;e vrednosti DEF i DETF korigovano za nivo kreatinina dobijene su kod ispitanica koje nisu konzumirale jabuke, a vi&scaron;e vrednosti DEF i DEDTF dobijene su kod ispitanica koje su konzumirale maline i kupine tokom trudnoće. Ostale grupe nisu pokazale statistički značajnu razliku među ispitivanim grupama. Zaključci: Izloženosti trudnica OF pesticidima nije značajno veća u grupi majki koje su rodile decu sa nespu&scaron;tenim testisom u odnosu na izloženost OF pesticidima kod majki zdrave mu&scaron;ke dece. Vrednosti metabolita OF pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat, dietilditiofosfat) u urinu majki koje su rodile mu&scaron;ku decu sa nespu&scaron;tenim testisima nije vi&scaron;a u odnosu na vrednosti metabolita OF pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat, dietilditiofosfat) izmerene u jutarnjem urinu majki koje su rodile zdravu mu&scaron;ku decu.</p> / <p>Undescended testis is the absence of testis in the scrotum on one or both sides. Risk factors for the occurrence of undescended testis include genetic predisposition, premature birth, low birth weight and prenatal exposure to endocrine disruptors or tobacco smoke. Endocrine disruptors are defined as exogenous substances that can affect homeostasis of the organism and the production of reproductive hormones. In this group are organophosphorus pesticides that are widely used in agriculture. Most of organophosphorus pesticides have anti-androgenic effect and with the fact that we live in a predominantly agricultural area, they are the focus of our interest. The aim of the research: The aim of this study is to determine the difference in exposure to organophosphorous pesticides using questionnaires created by standardized European model questionnaire QLK 4-1999-01422 in individuals who gave birth to a healthy male children and women who gave birth to children with undescended testis. In addition, the aim of this study is to determine and compare the value of metabolites of organophosphorus pesticides (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) in the urine of mothers who gave birth to male children with undescended testis and mothers who gave birth to healthy male children. Methodology: This work is randomized, prospective, clinical research conducted at the Clinic for gynaecology and obstetrics of the Clinical center of Vojvodina and the Department of Pharmacology and toxicology of the Faculty of Medicine, University of Novi Sad. This clinical research includes 50 new mothers that gave birth to male children with undescended testes (experimental group) and 53 new mothers that gave birth to healthy male children (control group) in the period from October 2012 to April 2018. During their stay at the maternity hospital the subjects were asked to fill out a questionnaire about habits and to give a urine sample for analyzing the level of metabolites of organophosphus pesticides. Urine samples were then prepared using the method described by Wu and associates 2010, and analyzed on gas chromatograph with a mass spectrophotometer Agilent 7890A brand. Results: Study groups do not differ according to the age of women (average age of control group is 29.41 &plusmn; 5.58 years, and experimental 30.54 &plusmn; 4.87 years). In both groups this was second pregnancy on average. The subjects did not distinguish either by the way of delivery. The average gestational weeks of pregnancy to childbirth was 39.45 &plusmn; 1.38 weeks for the control group and 39.20 &plusmn; 1.38 weeks for the experimental group, and birth weight of newborn was 3527.30 &plusmn; 470.16 g in control group and 3404.37 &plusmn; 508.20 g in the experimental group. There is no statistically significant difference in relation to the place of residence (50.9 % of the control group and 77.6 % of experimental live in the city), the living unit (67.9 % and 45.7 % of the control and experimental groups are living in the house) and the way of conception (6 % of experimental and 1.9 % of the control group reported IVF as a way of conception). Nearly half of both groups are smokers, and 32.7 % of women in the control group and 38.8 % in experimental smoked during pregnancy. Exposure to pesticides reported 50.9 % of mothers in control and 44 % of mothers in the experimental group. Professional exposure was reported by 3 control subjects and 2 subjects in experimental group. The subjects did not differ according to the origin of fruits and vegetables they were consuming, neither regarding the type of fruits they consumed during pregnancy. Average level of dimethylphosphate in control group was 5.604 &plusmn; 6.103 ug/L, and in experimental 4.815 &plusmn; 6.729 ug/l. Levels of diethylphosphate in control group were 0.408 &plusmn; 0.447 ug/L, and in experimental 0.461 &plusmn; 0.593 ug/l. DMDTP level in the control group was 0.431 &plusmn; 0.508 ug/L, and in experimental 0.547 &plusmn; 0570 ug/L, and the DETP was measured 0.403 &plusmn; 0.606 ug/L in control, and 0.725 &plusmn; 0.529 ug/L in the experimental group. These metabolites showed no statistically significant difference in the examined groups. Similar values are obtained for the adjusted values for creatinine level. Univariate regression analysis showed that the subjects who live in town are 3.3 times more likely to have child with undescended testis, and those who live in the apartment are 2.5 times more likely for the same outcome. Statistically significant difference was noticed in DEDTP level depending on the age of the subject and the living unit. Higher levels of DETP metabolites were detected in subjects that have been on hormonal therapy during pregnancy. The subjects who reported being exposed to pesticides during pregnancy had statistically significantly higher DMDTP values in relation to the subjects that were not exposed to pesticides. Similar results are obtained for the DEDTP level with higher levels in subjects owning pets. Statistically higher levels of DEP and DETP adjusted for creatinine were obtained in subjects that were not reporting eating apples, and higher levels of DEP and DEDTP were obtained in subjects that consumed raspberries and blackberries during pregnancy. Other groups showed no statistically significant difference between the study groups. Conclusion: Exposure of pregnant women to OP pesticides is not significantly greater in the group of mothers who gave birth to children with undescended testis in relation to exposure to OP pesticides in mothers of healthy male children. The level of OP metabolites (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) in the urine of mothers who gave birth to children with undescended testis is not higher in relation to the levels of OP metabolites (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) recorded in urine of mothers who gave birth to healthy male children.</p>
20

Parental exposures and occurrence of adverse pregnancy outcomes and childhood atopic diseases /

Magnusson, Linda L., January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 5 uppsatser.

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