491 research outputs found
Intermittent Preventive Treatment during Pregnancy and\ud Antenatal Care in Practice:A study from the Kilombero Valley, Tanzania
Each year an estimated 125 million pregnant women are at risk of getting infected with malaria in areas with P. falciparum and P. vivax transmission. In Tanzania, approximately 1.7 million pregnant women contract malaria each year leading to a high prevalence of maternal morbidity, maternal mortality and adverse birth outcomes. The World Health Organization (WHO) recommends for sub-Saharan Africa a package of prompt and effective case-management combined with the delivery of insecticide-treated nets (ITN) and intermittent preventive treatment during pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) through the national antenatal care (ANC) programs. Implemented in Tanzania around 2001, uptake of IPTp has been poor up to date with less then 30% of pregnant women receiving a full course of two SP doses. The aim of this thesis was to contribute to a better understanding of womenâs access to and use of IPTp and other ANC services in the Kilombero Valley, Tanzania. In order to explain low IPTp coverage levels, factors influencing ANC utilization on the demand side and the quality of ANC on the supply side were investigated. Drawing on conceptualizations of scholars from the âNew Institutionalismâ this thesis sought to provide a more in-depth understanding of 1) how rules, regulations and guidelines at the health system level influence health providersâ implementation of health policies and guidelines concerning IPTp and ANC and 2) how old and new norms and values at the household level and beyond influence womenâs access to and use of ANC and IPTp services. The study was conducted in close collaboration with the ACCESS Programme and was carried out in the Demographic and Surveillance System (DSS) area of the Kilombero and Ulanga district in south-eastern Tanzania. Research was conducted in three phases between April 2007 and June 2009 and combined a set of qualitative and quantitative methods for data collection. Our findings revealed a high coverage level of the first IPTp dose (79%) but confirmed a low uptake of the second one with only 27% of pregnant women having received two SP doses. Although 71% of all women started ANC after the four gestational months recommended by guidelines, their late attendance was not found to be the main constraint for IPTp delivery since 81% of the women had attended the ANC clinic at the time of the first IPTp delivery and 60% had attended both during the first and the second IPTp delivery period. The observation that among these women only 73% actually received one dose and only 29% received two doses of IPTp, pointed to the high number of missed opportunities. Low coverage levels for the second IPTp dose could be explained by health workers delivering IPTp to significantly less women during the second IPTp delivery period than the first one (55% vs. 73%) despite their high knowledge about the IPTp policy. Apart from womenâs late ANC initiation, it appeared that the majority of pregnant women respected the ANC schedule. However, it seemed that womenâs attendance was rather based on norms than on their awareness of the benefits of ANC services for their own and their childâs health. Late ANC initiation was associated with belonging to the Sukuma ethnic group, multiparity, and late recognition of pregnancy. Early ANC attendance, on the other hand, was triggered by primiparity, experience of a previous reproductive loss and feeling supported by the partner or husband. Maleâs support during pregnancy appeared to be facilitated and constrained by a broad range of institutions working along the lines of gender, family and kinship. On the other hand new norms and values imposed by the legal system or the âmodernâ health system were identified as being influential on menâs support during the prenatal period. Case studies in four health facilities revealed that the quality of ANC care was generally poor. Among a sample of 36 observed ANC consultations, 12 of the services recommended by the FANC guidelines were not given to any women, a further 18 services were given to 3%-58% and eight services were given to over 80% of women. Instead of FANC guidelines, health workers rather complied to ANC cards; analysis showed that health services for which information was required on the ANC card were delivered far better than services not listed on the ANC card but recommended by the FANC guidelines. Moreover, dichotomous IPTp schedules in the guidelines for ANC and malaria resulted in health workersâ continued delivery of IPTp according to restrictive IPTp schedules despite the existence of a more simplified IPTp schedule recommended by WHO. Calculations showed that the effective implementation of the latter guidelines could potentially increase IPTp coverage by up to 20 percentage points, which urgently calls for a revision of the national IPTp guidelines. Besides health policy factors, health care practices were found to be clearly shaped by health providersâ difficult working conditions. In order to cope with constraints caused by lack of trained staff, resource shortages and a high demand for their services, health workers appeared to adopt informal rules and routines such as attendance and diagnostics schedules and routines that allowed for mass treatment such as health education and counselling in groups. In order to better understand how the availability of material and human resources and health workersâ access to them influence health service delivery and its quality, this thesis proposed and applied the concept of âworkhoodâ as a new analytical device. By introducing an actors-perspective to the health system, the concept allowed light to be shed on the limitations and potentials of health workersâ capabilities.
Are tetraploids more successful? Floral signals, reproductive success and floral isolation in mixed-ploidy populations of a terrestrial orchid
Background and Aims Polyploidization, the doubling of chromosome sets, is common in angiosperms and has a range of evolutionary consequences. Newly formed polyploid lineages are reproductively isolated from their diploid progenitors due to triploid sterility, but also prone to extinction because compatible mating partners are rare. Models have suggested that assortative mating and increased reproductive fitness play a key role in the successful establishment and persistence of polyploids. However, little is known about these factors in natural mixed-ploidy populations. This study investigated floral traits that can affect pollinator attraction and efficiency, as well as reproductive success in diploid and tetraploid Gymnadenia conopsea (Orchidaceae) plants in two natural, mixed-ploidy populations. Methods Ploidy levels were determined using flow cytometry, and flowering phenology and herbivory were also assessed. Reproductive success was determined by counting fruits and viable seeds of marked plants. Pollinator-mediated floral isolation was measured using experimental arrays, with pollen flow tracked by means of staining pollinia with histological dye. Key Results Tetraploids had larger floral displays and different floral scent bouquets than diploids, but cytotypes differed only slightly in floral colour. Significant floral isolation was found between the two cytotypes. Flowering phenology of the two cytotypes greatly overlapped, and herbivory did not differ between cytotypes or was lower in tetraploids. In addition, tetraploids had higher reproductive success compared with diploids. Conclusions The results suggest that floral isolation and increased reproductive success of polyploids may help to explain their successful persistence in mixed-ploidy populations. These factors might even initiate transformation of populations from pure diploid to pure tetraploi
Floral adaptation to local pollinator guilds in a terrestrial orchid
Background and Aims Studies of local floral adaptation in response to geographically divergent pollinators are essential for understanding floral evolution. This study investigated local pollinator adaptation and variation in floral traits in the rewarding orchid Gymnadenia odoratissima, which spans a large altitudinal gradient and thus may depend on different pollinator guilds along this gradient. Methods Pollinator communities were assessed and reciprocal transfer experiments were performed between lowland and mountain populations. Differences in floral traits were characterized by measuring floral morphology traits, scent composition, colour and nectar sugar content in lowland and mountain populations. Key Results The composition of pollinator communities differed considerably between lowland and mountain populations; flies were only found as pollinators in mountain populations. The reciprocal transfer experiments showed that when lowland plants were transferred to mountain habitats, their reproductive success did not change significantly. However, when mountain plants were moved to the lowlands, their reproductive success decreased significantly. Transfers between populations of the same altitude did not lead to significant changes in reproductive success, disproving the potential for population-specific adaptations. Flower size of lowland plants was greater than for mountain flowers. Lowland plants also had significantly higher relative amounts of aromatic floral volatiles, while the mountain plants had higher relative amounts of other floral volatiles. The floral colour of mountain flowers was significantly lighter compared with the lowland flowers. Conclusions Local pollinator adaptation through pollinator attraction was shown in the mountain populations, possibly due to adaptation to pollinating flies. The mountain plants were also observed to receive pollination from a greater diversity of pollinators than the lowland plants. The different floral phenotypes of the altitudinal regions are likely to be the consequence of adaptations to local pollinator guild
Identification and regulation of expression of a gene encoding a filamentous hemagglutinin-related protein in Bordetella holmesii
Sclerosis multiplexâi tänapäevane ravi
Sclerosis multiplex (SM) on kþige sagedasem noortel täiskasvanutel puuet pþhjustav neuroloogiline haigus. Haiguskulu järgi eristatakse ägenemiste ja remissioonidega, ägenemistega sekundaarse progresseerumisega, ägenemisteta sekundaarse progresseerumisega ja primaarse progresseerumisega SMi vormi. SMi puhul on kasutusel
ägenemiste, haiguse kulgu mĂľjutav ja sĂźmptomaatiline ravi. Ăgenemiste raviks kasutatakse metßßlprednisolooni. Haiguse kulgu mĂľjutavad ravimid on profĂźlaktilised, vähendavad ägenemiste arvu ning on efektiivsed ainult ägenemistega haiguskulu korral. Ravimitest on esmavalikuna kasutusel sĂźstitavad beetainterferoonid ja glatirameeratsetaat. Esmavaliku preparaatide ebapiisava efektiivsuse vĂľi väga agressiivse kuluga haiguse puhul on näidustatud ka tsĂźtostaatiline ravi
mitoksantrooni vþi tsßklofosfamiidiga. Varajane ravi on tþhusam kui hiline. Käigusolevad ravimiuuringud annavad lootust, et tulevikus vþetakse kasutusele ka suu kaudu manustatavad preparaadid.
Eesti Arst 2009; 88(2):117â12
Measuring, comparing and interpreting phenotypic selection on floral scent
Natural selection on floral scent composition is a key element of the hypothesis that pollinators and other floral visitors drive scent evolution. The measure of such selection is complicated by the high-dimensional nature of floral scent data and uncertainty about the cognitive processes involved in scent-mediated communication. We use dimension reduction through reduced-rank regression to jointly estimate a scent composite trait under selection and the strength of selection acting on this trait. To assess and compare variation in selection on scent across species, time and space, we reanalyse 22 datasets on six species from four previous studies. The results agreed qualitatively with previous analyses in terms of identifying populations and scent compounds subject to stronger selection but also allowed us to evaluate and compare the strength of selection on scent across studies. Doing so revealed that selection on floral scent was highly variable, and overall about as common and as strong as selection on other phenotypic traits involved in pollinator attraction or pollen transfer. These results are consistent with an important role of floral scent in pollinator attraction. Our approach should be useful for further studies of plant-animal communication and for studies of selection on other high-dimensional phenotypes. In particular, our approach will be useful for studies of pollinator-mediated selection on complex scent blends comprising many volatiles, and when no prior information on the physiological responses of pollinators to scent compounds is available
Standardisierungen und Diversifizierungen in (inter)nationalen erziehungswissenschaftlichen Publikationskulturen
Die Autor*innen betrachten die wissenschaftspolitischen Vermessungen und kategorialen Zuordnungen erziehungswissenschaftlicher Zeitschriften in Italien. Diese Zeitschriftenlisten favorisieren insbesondere Internationalität im Sinne englischsprachigen Publizierens. Anhand einer Zeitschriftenanalyse deutsch- und englischsprachiger Beiträge zeigen sie jedoch die schwache wechselseitige Bezugnahme in der erziehungswissenschaftlichen Kommunikation zwischen Italien und Deutschland. (DIPF/Orig.
Measuring, comparing and interpreting phenotypic selection on floral scent
Natural selection on floral scent composition is a key element of the hypothesis that pollinators and other floral visitors drive scent evolution. The measure of such selection is complicated by the high-dimensional nature of floral scent data and uncertainty about the cognitive processes involved in scent-mediated communication. We use dimension reduction through reduced-rank regression to jointly estimate a scent composite trait under selection and the strength of selection acting on this trait. To assess and compare variation in selection on scent across species, time and space, we reanalyse 22 datasets on six species from four previous studies. The results agreed qualitatively with previous analyses in terms of identifying populations and scent compounds subject to stronger selection but also allowed us to evaluate and compare the strength of selection on scent across studies. Doing so revealed that selection on floral scent was highly variable, and overall about as common and as strong as selection on other phenotypic traits involved in pollinator attraction or pollen transfer. These results are consistent with an important role of floral scent in pollinator attraction. Our approach should be useful for further studies of plant-animal communication and for studies of selection on other high-dimensional phenotypes. In particular, our approach will be useful for studies of pollinator-mediated selection on complex scent blends comprising many volatiles, and when no prior information on the physiological responses of pollinators to scent compounds is available.Peer reviewe
High-Dose Enalapril Treatment Reverses Myocardial Fibrosis in Experimental Uremic Cardiomyopathy
AIMS: Patients with renal failure develop cardiovascular alterations which contribute to the higher rate of cardiac death. Blockade of the renin angiotensin system ameliorates the development of such changes. It is unclear, however, to what extent ACE-inhibitors can also reverse existing cardiovascular alterations. Therefore, we investigated the effect of high dose enalapril treatment on these alterations. METHODS: Male Sprague Dawley rats underwent subtotal nephrectomy (SNX, nâ=â34) or sham operation (sham, nâ=â39). Eight weeks after surgery, rats were sacrificed or allocated to treatment with either high-dose enalapril, combination of furosemide/dihydralazine or solvent for 4 weeks. Heart and aorta were evaluated using morphometry, stereological techniques and TaqMan PCR. RESULTS: After 8 and 12 weeks systolic blood pressure, albumin excretion, and left ventricular weight were significantly higher in untreated SNX compared to sham. Twelve weeks after SNX a significantly higher volume density of cardiac interstitial tissue (2.57Âą0.43% in SNX vs 1.50Âą0.43% in sham, p<0.05) and a significantly lower capillary length density (4532Âą355 mm/mm(3) in SNX vs 5023Âą624 mm/mm(3) in sham, p<0.05) were found. Treatment of SNX with enalapril from week 8-12 significantly improved myocardial fibrosis (1.63Âą0.25%, p<0.05), but not capillary reduction (3908Âą486 mm/mm(3)) or increased intercapillary distance. In contrast, alternative antihypertensive treatment showed no such effect. Significantly increased media thickness together with decreased vascular smooth muscles cell number and a disarray of elastic fibres were found in the aorta of SNX animals compared to sham. Both antihypertensive treatments failed to cause complete regression of these alterations. CONCLUSIONS: The study indicates that high dose ACE-I treatment causes partial, but not complete, reversal of cardiovascular changes in SNX
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